Leveraging the high resolution,sensitivity,and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array(ALMA),the QUARKS survey,standing for“Querying Underlying mechanisms of massive star formation...Leveraging the high resolution,sensitivity,and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array(ALMA),the QUARKS survey,standing for“Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures”,is observing 139 massive starforming clumps at ALMA Band 6(λ~1.3 mm).This paper introduces the Atacama Compact Array(ACA)7 m data of the QUARKS survey,describing the ACA observations and data reduction.Combining multiwavelength data,we provide the first edition of QUARKS atlas,offering insights into the multiscale and multiphase interstellar medium in high-mass star formation.The ACA 1.3 mm catalog includes 207 continuum sources that are called ACA sources.Their gas kinetic temperatures are estimated using three formaldehyde transitions with a non-LTE radiation transfer model,and the mass and density are derived from a dust emission model.The ACA sources are massive(16–84 percentile values of 6–160 M_(⊙)),gravity-dominated(M∝R^(1.1))fragments within massive clumps,with supersonic turbulence(M>1)and embedded star-forming protoclusters.We find a linear correlation between the masses of the fragments and the massive clumps,with a ratio of 6%between the two.When considering fragments as representative of dense gas,the ratio indicates a dense gas fraction(DGF)of 6%,although with a wide scatter ranging from 1%to 10%.If we consider the QUARKS massive clumps to be what is observed at various scales,then the size-independent DGF indicates a self-similar fragmentation or collapsing mode in protocluster formation.With the ACA data over four orders of magnitude of luminosity-to-mass ratio(L/M),we find that the DGF increases significantly with L/M,which indicates clump evolutionary stage.We observed a limited fragmentation at the subclump scale,which can be explained by a dynamic global collapse process.展开更多
Pollination niches,which encompass the factors influencing pollen exchange among angiosperms,are fundamental to understanding reproductive success and the intricate eco-evolutionary dynamics of plants.In this study,we...Pollination niches,which encompass the factors influencing pollen exchange among angiosperms,are fundamental to understanding reproductive success and the intricate eco-evolutionary dynamics of plants.In this study,we investigated pollination niche shift among four sympatric Eriosyce cacti with restricted distributions in the South American Mediterranean region.Utilizing a comprehensive approachdincluding pollination niche analysis,pollinator color perception studies,reproductive output assessments,molecular phylogenetics,gene flow analyses,and species distribution modelingdwe revealed a significant pollination niche displacement in E.chilensis and its variety,E.chilensis var.albidiflora.These taxa transitioned from a hummingbird-pollinated system prevalent in the Eriosyce sect.Neoporteria,characteristic of their sister species E.litoralis,to a bee-pollination strategy akin to that of the co-occurring species E.mutabilis.This shift highlights a simultaneous convergence of E.chilensis toward E.mutabilis and divergence from E.litoralis in pollination strategies,providing adaptive advantages by reducing pollen limitation and enhancing seed production.The morphological and flowering phenological similarities between E.chilensis and E.mutabilis suggest the evolution of a shared advertising display,potentially indicative of floral mimicry,wherein both species benefit from attracting shared bee pollinators.Genomic analyses reveal distinct pollinator-driven selection pressures,with E.chilensis/E.albidiflora exhibiting traits that promote reproductive isolation from E.litoralis,supporting a scenario of rapid speciation occurring within the past half of million years in the absence of geographic barriers.These findings underscore the pivotal role of pollinator interactions in shaping angiosperm speciation and biodiversity,highlighting their dynamic influence on ecological and evolutionary processes.展开更多
Oral squamous cell carcinoma(OSCC)is the most common manifestation of oral cancer.It has been proposed that periodontal pathogens contribute to OSCC progression,mainly by their virulence factors.However,the main perio...Oral squamous cell carcinoma(OSCC)is the most common manifestation of oral cancer.It has been proposed that periodontal pathogens contribute to OSCC progression,mainly by their virulence factors.However,the main periodontal pathogen and its mechanism to modulate OSCC cells remains not fully understood.In this study we investigate the main host-pathogen pathways in OSCC by computational proteomics and the mechanism behind cancer progression by the oral microbiome.The main hostpathogen pathways were analyzed in the secretome of biopsies from patients with OSCC and healthy controls by mass spectrometry.Then,functional assays were performed to evaluate the host-pathogen pathways highlighted in oral cancer.Host proteins associated with LPS response,cell migration/adhesion,and metabolism of amino acids were significantly upregulated in the human cancer proteome,whereas the complement cascade was downregulated in malignant samples.Then,the microbiome analysis revealed large number and variety of peptides from Fusobacterium nucleatum(F.nucleatum)in OSCC samples,from which several enzymes from the L-glutamate degradation pathway were found,indicating that L-glutamate from cancer cells is used as an energy source,and catabolized into butyrate by the bacteria.In fact,we observed that F.nucleatum modulates the cystine/glutamate antiporter in an OSCC cell line by increasing SLC7A11 expression,promoting L-glutamate efflux and favoring bacterial infection.Finally,our results showed that F.nucleatum and its metabolic derivates promote tumor spheroids growth,spheroidsderived cell detachment,epithelial-mesenchymal transition and Galectin-9 upregulation.Altogether,F.nucleatum promotes protumoral mechanism in oral cancer.展开更多
The onset and mechanisms underlying neurodegenerative diseases remain uncertain. The main features of neurodegenerative diseases have been related with cellular and molecular events like neuronal loss, mitochondrial d...The onset and mechanisms underlying neurodegenerative diseases remain uncertain. The main features of neurodegenerative diseases have been related with cellular and molecular events like neuronal loss, mitochondrial dysfunction and aberrant accumulation of misfolded proteins or peptides in specific areas of the brain. The most prevalent neurodegenerative diseases belonging to age-related pathologies are Alzheimer's disease, Huntington's disease, Parkinson's disease and amyotrophic lateral sclerosis. Interestingly, mitochondrial dysfunction has been observed to occur during the early onset of several neuropathological events associated to neurodegenerative diseases. The master regulator of mitochondrial quality control and energetic metabolism is the transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator 1-alpha(PGC-1α). Additionally, it has been observed that PGC-1α appears to be a key factor in maintaining neuronal survival and synaptic transmission. In fact, PGC-1α downregulation in different brain areas(hippocampus, substantia nigra, cortex, striatum and spinal cord) that occurs in function of neurological damage including oxidative stress, neuronal loss, and motor disorders has been seen in several animal and cellular models of neurodegenerative diseases. Current evidence indicates that PGC-1α upregulation may serve as a potent therapeutic approach against development and progression of neuronal damage. Remarkably, increasing evidence shows that PGC-1α deficient mice have neurodegenerative diseases-like features, as well as neurological abnormalities. Finally, we discuss recent studies showing novel specific PGC-1α isoforms in the central nervous system that appear to exert a key role in the age of onset of neurodegenerative diseases and have a neuroprotective function in the central nervous system, thus opening a new molecular strategy for treatment of neurodegenerative diseases. The purpose of this review is to provide an up-to-date overview of the PGC-1α role in the physiopathology of neurodegenerative diseases, as well as establish the importance of PGC-1α function in synaptic transmission and neuronal survival.展开更多
Variable-top stem biomass models at the tree level for second growth forests of roble (Nothofagus obliqua), rauli(Nothofagus alpina), and coigüe (Nothofagus dombeyi) were fitted by a simultaneous density-integral...Variable-top stem biomass models at the tree level for second growth forests of roble (Nothofagus obliqua), rauli(Nothofagus alpina), and coigüe (Nothofagus dombeyi) were fitted by a simultaneous density-integral system, which combines a stem taper model and a wood basic density model. For each model, an autoregressive structure of order 2 and a power equation of residual variance were incorporated to reduce residual autocorrelation and heteroscedasticity, respectively. By using dummy variables in the regression analysis, zonal effects on the parameters in the variable-top stem biomass equations were detected in roble. Consequently, equations for clusters of zones were obtained. These equations presented significant parameters and a high precision in both fitting and validation processes (i.e., CV<11.5% and CVp<11.9%, respectively), demonstrating that they are unbiased. The advantage of these types of functions is that they provide estimates of volume and biomass of sections of the stem, defined between any two points of the stem in the three species. Thus, depending on the final use of the wood and the dimensions of the tree, a stem fraction can be quantified in units of volume and the remaining fraction in units of weight.展开更多
This study evaluated the expression of defense compounds from the secondary metabolism of Eucalyptus globulus plants, subjected to direct and indirect stimuli by the insect Ctenarytaina eucalypti (blue gum Psyllid). R...This study evaluated the expression of defense compounds from the secondary metabolism of Eucalyptus globulus plants, subjected to direct and indirect stimuli by the insect Ctenarytaina eucalypti (blue gum Psyllid). Results showed that defense responses were activated in plants in all tested cases. Were detected and identified thirty-two compounds in the leaves of treated plants, of which five compounds differed with the control, and all are part of the chemical defenses from the plants, three of them were oxygenated monoterpenes (borneol, exo-2-hydroxy cineole and thymol), a aromatic carboxylic acid (benzoic acid) and a quinone (6-acethyl-flaviolin). The plants induced by volatile compounds and by indirect entomological manner, showed its capability to synthesize defensive compounds without a wound that promotes these responses. Were also found some constitutive secondary metabolites over expressed in the different inductions compared with the control.展开更多
In this study,three semipredictive activity coefficient models:Wilson,non-random-two liquid model(NRTL),and universal quasi-chemical model(UNIQUAC),have been used for modeling vapor-liquid equilibrium properties of te...In this study,three semipredictive activity coefficient models:Wilson,non-random-two liquid model(NRTL),and universal quasi-chemical model(UNIQUAC),have been used for modeling vapor-liquid equilibrium properties of ternary mixtures that include substances found in alcoholic distillation processes of wine and musts.In particular,vapor-liquid equilibrium in ternary mixtures containing water + ethanol + congener has been modeled using parameters obtained from binary and ternary mixture data.The congeners are substances that although present in very low concentrations,of the order of part per million,are important enological parameters.The results given by these different models have been compared with literature data and conclusions about the accuracy of the models studied are drawn,recommending the best models for correlating and predicting phase equilibrium properties of this type of mixtures.展开更多
Estimating and identifying friction are important aspects of simulating a mechanical drive system. Accurate friction modeling helps to improve a telescope's performance. However, the friction conditions inside are...Estimating and identifying friction are important aspects of simulating a mechanical drive system. Accurate friction modeling helps to improve a telescope's performance. However, the friction conditions inside are complex and hard to measure. We did simulations with mathematical transfer functions for the Leighton 10 m Telescope and employed a polyline model to identify sources of friction. We made a two-stage model for the Leighton 10 m Telescope. Based on measurements of the motor's currents and speeds, we constructed a curve containing the friction information of the transmission elements. We simulated the system using a step function input under many combinations of friction parameters. By comparing simulation results with the measured ones, we determined the various friction components. This model accurately reproduced the telescope performance including the nonlinearities.展开更多
Different La2O3 contents（0, 1, 2, 3, and 5 wt%） were used to prepared La2O3-ZrO2 mixed oxides calcined at 600 ℃ by the sol-gel method. The catalytic activity was measured as biodiesel production from canola oil thr...Different La2O3 contents（0, 1, 2, 3, and 5 wt%） were used to prepared La2O3-ZrO2 mixed oxides calcined at 600 ℃ by the sol-gel method. The catalytic activity was measured as biodiesel production from canola oil through a transesterification reaction. The characterization results indicate that the La2O3 monolayer formation and extent of basicity of m-ZrO2 have a large influence on biodiesel production.Greater biodiesel conversion（56% at 4 h） was obtained with the 3% La2O3-ZrO2 catalyst in the presence of basic sites and the formation of a monolayer of La2O3. The decrease in the catalytic activity for 5% La2O3-ZrO2 resulted from the loss of active sites on the catalyst because of agglomeration, which was suggested by XPS and the isoelectric point. The kinetic data fit to a pseudo-first order constant, and the largest kinetic constant corresponds to 3% La2O3-ZrO2, currently the largest heterogeneous non-alkaline metal catalyst reported for a transesterification reaction.展开更多
Coastal zones are very dynamic and fragile environments, constituting a landscape ever more heterogeneous, fragmented and with increasing levels of complexity due to the changing relationship between man and nature. I...Coastal zones are very dynamic and fragile environments, constituting a landscape ever more heterogeneous, fragmented and with increasing levels of complexity due to the changing relationship between man and nature. Integrated coastal zone management therefore requires detailed knowledge of the system and its components, based—to a large extent—on technical and scientific information. However, the information generated must be in line with the political requirements necessary for decision-making and planning. Thus the use of indicators to give a simplified view of the many components of the territory, and at the same time to provide important information about patterns or trends, becomes a tool of the utmost importance. These indicators can be understood as measurable characteristics of the environment, which facilitate comprehension of the processes occurring at different scales and serve as a reference to inform the population and support decision-making. The aim of the present note is to demonstrate briefly the need to develop geographical-environmental and natural risk indicators to facilitate comprehension of the dynamic of spatial and temporal landscape patterns, particularly in coastal environments. This approach offers an historical summary of the natural, socio-economic and political processes which currently make up the territory, and which without doubt will continue to influence it in the future. At the same time, it is proposed that information should be integrated on the basis of this framework with a view to generating spatial decision support systems in a context of planning and integrated management of the coastal zones of Chile.展开更多
The volatilization kinetics of senarmontite(Sb_(2)O_(3))was analyzed in a neutral atmosphere in two temperature ranges:550-615°C(roasting temperature)and 660-1100°C(melting temperature)by using a thermogravi...The volatilization kinetics of senarmontite(Sb_(2)O_(3))was analyzed in a neutral atmosphere in two temperature ranges:550-615°C(roasting temperature)and 660-1100°C(melting temperature)by using a thermogravimetric analysis method under various gas flow rates and using a 1.3 m L ceramic crucible(11 mm in internal diameter and 14 mm in height).The effect of particle size was also analyzed.The experimental results of mass loss data,X-ray diffraction(XRD)analysis of partially reacted samples and thermodynamic studies indicate that the senarmontite becomes volatile in the form of Sb_(4)O_(6)(g)without the formation of any intermediary compound in the entire temperature range.At roasting temperatures,the volatilization kinetics of Sb_(2)O_(3) was analyzed using the model X=kappt.The volatilization reaction was controlled by the surface chemical reaction and an activation energy value of 193.0 k J/mol was obtained in this temperature range.Based on the volatilization kinetics at the melting temperatures,for linear behaviour in nitrogen gas,kinetic constants were determined,and an activation energy of 73.9 k J/mol was calculated for the volatilization reaction with a surface area of 8.171×10^(-5)m^(2).展开更多
Background: Coupling biomass models with nutrient concentrations can provide sound estimations of carbon and nutrient contents, enabling the improvement of carbon and nutrient balance in forest ecosystems. Although nu...Background: Coupling biomass models with nutrient concentrations can provide sound estimations of carbon and nutrient contents, enabling the improvement of carbon and nutrient balance in forest ecosystems. Although nutrient concentrations are often assumed to be constant for some species and specific tree components, at least in mature stands,the concentrations usually vary with age, site index and even with tree density. The main objective of this study was to evaluate the sources of variation in nutrient concentrations in biomass compartments usually removed during harvesting operations, covering a range of species and management conditions: semi-natural forest, conventional forest plantations and short rotation forestry(SRF). Five species(Betula pubescens, Quercus robur, Eucalyptus globulus, Eucalyptus nitens and Populus spp.) and 14 genotypes were considered. A total of 430 trees were sampled in 61 plots to obtain 6 biomass components:leaves, twigs, thin branches, thick branches, bark and wood. Aboveground leafless biomass was pooled together forpoplar.The concentrations of C, N, K, P, Ca, Mg, S, Fe, Mn, Cu, Zn and B were measured and the total biomass of each sampled tree and plot were determined. The data were analysed using boosted regression trees and conventional techniques.Results: The main sources of variation in nutrient concentrations were biomass component > > genotype(species) ≈ age >tree diameter. The concentrations of Ca, Mg and K were most strongly affected by genotype and age. The concentrations of P, K, Ca, Mg, S and Cu in the wood component decreased with age, whereas C concentrations increased, with a trend to reach 50% in the older trees. In the SRF, interamerican poplar and P. trichocarpa genotypes were comparatively more efficient in terms of Ca and K nutrient assimilation index(NAI)(+65-85%) than eucalypts, mainly because leafless biomass can be removed. In the conventional eucalypt plantations(rotation 15 years), debarking the wood at logging(savings of225% of Ca and 254% of Mg for E. globulus) or the use of selected genotypes(savings of 45% of P and 35% of Ca) will provide wood at a relatively lower nutrient cost. Considering all the E. globulus genotypes together, the management for pulp with removal of debarked wood shows NAI values well above(x 1.7-x 3.9) the ones found for poplar or eucalypt SRF and also higher(x 1.6-x4.0) than the ones found for oak and birch managed in medium or long rotations.The annual rates of nutrient removal were low in the native broadleaved species but the rates of available soil nutrients removed were high as compared to poplar or eucalypts. Management of native broadleaved species should consider nutrient stability through selection of the biomass compartments removed.(Continued on next page)(Continued from previous page)Conclusions: The nutrient assimilation index is higher in poplar grown under short rotation forestry management than in the other systems considered. Nutrient management of fast growing eucalyptus plantations could be improved by selecting efficient genotypes and limiting removal of wood. The values of the nutrient assimilation index are lower in the natural stands of native broadleaved species than in the other systems considered.展开更多
Postharvest waste and loss of horticultural crops exacerbates the agricultural problems facing humankind and will continue to do so in the next decade.Fruits and vegetables provide us with a vast spectrum of healthful...Postharvest waste and loss of horticultural crops exacerbates the agricultural problems facing humankind and will continue to do so in the next decade.Fruits and vegetables provide us with a vast spectrum of healthful nutrients,and along with ornamentals,enrich our lives with a wide array of pleasant sensory experiences.These commodities are,however,highly perishable.Approximately 33%of the produce that is harvested is never consumed since these products naturally have a short shelf-life,which leads to postharvest loss and waste.This loss,however,could be reduced by breeding new crops that retain desirable traits and accrue less damage over the course of long supply chains.New gene-editing tools promise the rapid and inexpensive production of new varieties of crops with enhanced traits more easily than was previously possible.Our aim in this review is to critically evaluate gene editing as a tool to modify the biological pathways that determine fruit,vegetable,and ornamental quality,especially after storage.We provide brief and accessible overviews of both the CRISPR-Cas9 method and the produce supply chain.Next,we survey the literature of the last 30 years,to catalog genes that control or regulate quality or senescence traits that are"ripe"for gene editing.Finally,we discuss barriers to implementing gene editing for postharvest,from the limitations of experimental methods to international policy.We conclude that in spite of the hurdles that remain,gene editing of produce and ornamentals will likely have a measurable impact on reducing postharvest loss and waste in the next 5-10 years.展开更多
Let K be a complete algebraically closed p-adic field of characteristic zero. We apply results in algebraic geometry and a new Nevanlinna theorem for p-adic meromorphic functions in order to prove results of uniquenes...Let K be a complete algebraically closed p-adic field of characteristic zero. We apply results in algebraic geometry and a new Nevanlinna theorem for p-adic meromorphic functions in order to prove results of uniqueness in value sharing prob-lems, both on K and on C. Let P be a polynomial of uniqueness for meromorphic functions in K or C or in an open disk. Let f , g be two transcendental meromorphic functions in the whole field K or in C or meromorphic functions in an open disk of K that are not quotients of bounded analytic functions. We show that if f′P′（ f ） and g′P′（g） share a small function α counting multiplicity, then f=g, provided that the multiplicity order of zeros of P′satisfy certain inequalities. A breakthrough in this pa-per consists of replacing inequalities n≥k＋2 or n≥k＋3 used in previous papers by Hypothesis （G）. In the p-adic context, another consists of giving a lower bound for a sum of q counting functions of zeros with （q-1） times the characteristic function of the considered meromorphic function.展开更多
Although the degree of mate competition, given extreme differences in sex ratio, explains much of the pattern of male-biased size dimorphism among diverse taxa, it fails for some species which have potential for inten...Although the degree of mate competition, given extreme differences in sex ratio, explains much of the pattern of male-biased size dimorphism among diverse taxa, it fails for some species which have potential for intense male competition for mates and yet exhibit little or no sexual size dimorphism （SSD）. This fact suggest that species with low SSD should be express the effect of evolutionary pressure in non-obvious geometrical shape promoted by sex ratio in an evolutionary time scale. To evaluate this hypothesis we used phylogenetic comparative method in a Bayesian framework to investigate the evolution of SSD and the role of sex ratio at inter-specific level in the species of Ceroglossus （Coleoptera： Carabidae）. In our results the proportion farthest from 1：1 is associated with more disparate body shape, even though the entire group has minimum variation in sex ratio, which is an intrinsic life history character of this group considering its phylogenetic conservatism or phylogenetic signal. We suggest that the sex ratio has determined the dimorphism degree during evolution of this group, since both traits have increased or decreased together during the species divergence （i.e. positive phylogenetic correlation： r2=0.85）. We suggest that morphological studies of SSD will benefit from using comparative method with Bayesian approaches to assess the effect of phylogenetic history and its uncertainty. Finally, this will be allow to researchers to quantify the uncertainty of specific evolutionary hypotheses accounting for observed sexual dimorphism patterns.展开更多
The reinforcing impact of Lignocellulosic micro and nanofibrillated cellulose(L-MNFCs)obtained from Eucalyp-tus Globulus bark in Urea-Formaldehyde UF adhesive was tested.L-MNFCs were prepared by an environmentally fri...The reinforcing impact of Lignocellulosic micro and nanofibrillated cellulose(L-MNFCs)obtained from Eucalyp-tus Globulus bark in Urea-Formaldehyde UF adhesive was tested.L-MNFCs were prepared by an environmentally friendly,low-cost process using a combination process involving steam explosion followed by refining and ultra-fine grinding.Obtained L-MNFCs showed a web-like morphology with some aggregates and lignin nanodroplets.They present a mixture of residual fibers and fine elements with a width varying between 5 nm to 20μm,respec-tively.The effects of the addition of low amounts of L-MNFCs(1%wt.)on the properties of three different adhe-sives(Urea-Formaldehyde UF,Phenol-Formaldehyde PF,and Tannin-Hexamine TH)were studied by the evolution of the pH,the viscosity,and the mechanical properties.Results showed that the viscosity of PF and UF adhesives increased with the addition of L-MNFCs,unlike TH.Meanwhile,the addition led to better mechan-ical behavior for the three adhesives.Particleboards were then prepared using modified UF with L-MNFCs and tested.Results showed that an amount of 1%wt.of L-MNFCs was sufficient to increase the internal bonding by≈67%,the modulus of elasticity by≈43%,and the modulus of rupture by≈29%.展开更多
The 3D reconstruction and quantitative characterization of drainage channels and coarse tailings particles in a bed were conducted in this study.The influence of variations in the azimuthal angle(θ)and polar angle(φ...The 3D reconstruction and quantitative characterization of drainage channels and coarse tailings particles in a bed were conducted in this study.The influence of variations in the azimuthal angle(θ)and polar angle(φ)of coarse particles on drainage channel structure was analyzed,and the drainage mechanism of the bed was studied.Results showed that water discharge in the bed reduced the size of pores and throat channels,increasing slurry concentration.The throat channel structure was a key component of the drainage process.Theφandθof particles changed predominantly along the length direction.The changes inφhad a cumulative plugging effect on the drainage channel and increased the difficulty of water discharge.The rake and rod formed a shear ring in the tailings bed with shear,and theθdistribution of particles changed from disorderly to orderly during the rotation process.The drainage channel was squeezed during the shearing process with the change inθ,which broke the channel structure,encouraged water discharge in the bed,and facilitated a further increase in slurry concentration.The findings of this work are expected to offer theoretical guidance for preparing high-concentration underflow in the tailings thickening process.展开更多
We searched for long period variation in V-band, It-band and RXTE X-ray light curves of the High Mass X-ray Binaries （HMXBs） LS 1698 / RX J1037.5-5647, HD 110432 / 1H 1249-637 and HD 161103 / RX J1744.7-2713 in an a...We searched for long period variation in V-band, It-band and RXTE X-ray light curves of the High Mass X-ray Binaries （HMXBs） LS 1698 / RX J1037.5-5647, HD 110432 / 1H 1249-637 and HD 161103 / RX J1744.7-2713 in an attempt to discover orbitally induced variation. Data were obtained primarily from the ASAS database and were supplemented by shorter term observations made with the 24- and 40-inch ANU telescopes and one of the robotic PROMPT telescopes. Fourier periodograms suggested the existence of long period variation in the V-band light curves of all three HMXBs, however folding the data at those periods did not reveal convincing periodic variation. At this point we cannot rule out the existence of long term V-band variation for these three sources and hints of longer term variation may be seen in the higher precision PROMPT data. Long term V-band observations, on the order of several years, taken at a frequency of at least once per week and with a precision of 0.01 mag, therefore still have a chance of revealing long term variation in these three HMXBs.展开更多
The collision of a divergent ocean ridge may evolve into two end cases： in the continuity of ocean-floor subduction, or in the detachment of the subducted plate. The northern Patagonia active plate margin has the uni...The collision of a divergent ocean ridge may evolve into two end cases： in the continuity of ocean-floor subduction, or in the detachment of the subducted plate. The northern Patagonia active plate margin has the unique situation that in Cenozoic time it has been subjected to two divergent ridge collisions, each one representing one of the end members. The Neogene Antarctica-Nazca divergent ridge collision evolved as a continuous ocean-floor subduction system, promoting a magmatic hiatus at the arc axis, the obduction of part of the ridge ocean-floor in the fore-arc, and basaltic volcanism in the back-arc. In contrast, the Paleogene Farallon-Aluk divergent ridge collision evolved into a transform margin, with the detachment and sinking of the Aluk plate and the development of a large slab window. As in the previous case, this collision promoted a magmatic hiatus at the arc axis, but the tectono-magmatic scenario changed to postorogenic synextensional volcanism that spread to the former fore-arc （basalt, andesite, rhyolite） and former back-arc （bimodal ignimbrite flare-up, basalt）. Geochemistry of this slab window synextensional volcanism shows more MORB-like basalts towards the former fore-arc, and MORB-OIB-Iike basalts towards the former back-arc. Instead, an isolated undeformable crustal block in the former back-arc, with an ＂epeirogenic＂ response to the slab window and extensional regime, was covered by OIB-type basalts after uplift. Major elements show that slab window basalts reach TiO2 values up to 3 wt%, as compared with the top value of 1.5 wt% of arc magmas. Besides, the MgO with respect to （FeOt ＋ A1203） ratio helps to distinguish slab window magma changes from the former fore-arc to the former back-arc and also with respect to the ＂epeirogenic＂ block. Higher contents of HFS elements such as Nb and Ta also help to distinguish this slab window from arc magmas and also, to distinguish slab window magma changes from the former fore-arc to the former back-arc and ＂epeirogenic＂ block settings. The isotope compositions of slab window magmatism show a disparate coeval array from MORB to crustal sources, interpreted as a consecluence of the lack of protracted storage and homogenization due to the extensional setting.展开更多
The monitoring of trees is crucial for the management of large areas of forest cultivations,but this process may be costly.However,remotely sensed data offers a solution to automate this process.In this work,we used t...The monitoring of trees is crucial for the management of large areas of forest cultivations,but this process may be costly.However,remotely sensed data offers a solution to automate this process.In this work,we used two neural network methods named You Only Look Once(YOLO)and Mask R-CNN to overcome the challenging tasks of counting,detecting,and segmenting high dimensional Red–Green–Blue(RGB)images taken from unmanned aerial vehicles(UAVs).We present a processing framework,which is suitable to generate accurate predictions for the aforementioned tasks using a reasonable amount of labeled data.We compared our method using forest stands of different ages and densities.For counting,YOLO overestimates 8.5%of the detected trees on average,whereas Mask R-CNN overestimates a 4.7%of the trees.For the detection task,YOLO obtains a precision of 0.72 and a recall of 0.68 on average,while Mask R-CNN obtains a precision of 0.82 and a recall of 0.80.In segmentation,YOLO overestimates a 13.5%of the predicted area on average,whereas Mask R-CNN overestimates a 9.2%.The proposed methods present a cost-effective solution for forest monitoring using RGB images and have been successfully used to monitor∼146,500 acres of pine cultivations.展开更多
基金upported by the National Natural Science Foundation of China(NSFC,Grant No.12033005)the National Key R&D Program of China(No.2022YFA1603102)+2 种基金the China Manned Space Project(CMS-CSST-2021-A09,CMS-CSST-2021-B06)the China-Chile Joint Research Fund(CCJRF No.2211)support from the Tianchi Talent Program of Xinjiang Uygur Autonomous Region。
文摘Leveraging the high resolution,sensitivity,and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array(ALMA),the QUARKS survey,standing for“Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures”,is observing 139 massive starforming clumps at ALMA Band 6(λ~1.3 mm).This paper introduces the Atacama Compact Array(ACA)7 m data of the QUARKS survey,describing the ACA observations and data reduction.Combining multiwavelength data,we provide the first edition of QUARKS atlas,offering insights into the multiscale and multiphase interstellar medium in high-mass star formation.The ACA 1.3 mm catalog includes 207 continuum sources that are called ACA sources.Their gas kinetic temperatures are estimated using three formaldehyde transitions with a non-LTE radiation transfer model,and the mass and density are derived from a dust emission model.The ACA sources are massive(16–84 percentile values of 6–160 M_(⊙)),gravity-dominated(M∝R^(1.1))fragments within massive clumps,with supersonic turbulence(M>1)and embedded star-forming protoclusters.We find a linear correlation between the masses of the fragments and the massive clumps,with a ratio of 6%between the two.When considering fragments as representative of dense gas,the ratio indicates a dense gas fraction(DGF)of 6%,although with a wide scatter ranging from 1%to 10%.If we consider the QUARKS massive clumps to be what is observed at various scales,then the size-independent DGF indicates a self-similar fragmentation or collapsing mode in protocluster formation.With the ACA data over four orders of magnitude of luminosity-to-mass ratio(L/M),we find that the DGF increases significantly with L/M,which indicates clump evolutionary stage.We observed a limited fragmentation at the subclump scale,which can be explained by a dynamic global collapse process.
基金supported by the Fondo Nacional de Desarrollo Científico y Tecnologico[1160583 and 1211441 to P.C.G.,1240877 to G.O.C.]the Comision Nacional de Investigacion Científica y Tecnologica PIA[REDII 170031 to P.C.G., G.O.C.]+3 种基金ANID PIA/BASAL[FB210006]to the Instituto de Ecología y Biodiversidad(IEB)ANID PIA/BASAL[PFB210018]to the Cape Horn International Center(CHIC)A.V.M.acknowledges the support of ANID/BASAL FB210006 by the Institute of EcologyBiodiversity(IEB)with counterpart contributions from the Anglo-American Foundation.B.M.M.is grateful to the ANID Scholarship 20210673.
文摘Pollination niches,which encompass the factors influencing pollen exchange among angiosperms,are fundamental to understanding reproductive success and the intricate eco-evolutionary dynamics of plants.In this study,we investigated pollination niche shift among four sympatric Eriosyce cacti with restricted distributions in the South American Mediterranean region.Utilizing a comprehensive approachdincluding pollination niche analysis,pollinator color perception studies,reproductive output assessments,molecular phylogenetics,gene flow analyses,and species distribution modelingdwe revealed a significant pollination niche displacement in E.chilensis and its variety,E.chilensis var.albidiflora.These taxa transitioned from a hummingbird-pollinated system prevalent in the Eriosyce sect.Neoporteria,characteristic of their sister species E.litoralis,to a bee-pollination strategy akin to that of the co-occurring species E.mutabilis.This shift highlights a simultaneous convergence of E.chilensis toward E.mutabilis and divergence from E.litoralis in pollination strategies,providing adaptive advantages by reducing pollen limitation and enhancing seed production.The morphological and flowering phenological similarities between E.chilensis and E.mutabilis suggest the evolution of a shared advertising display,potentially indicative of floral mimicry,wherein both species benefit from attracting shared bee pollinators.Genomic analyses reveal distinct pollinator-driven selection pressures,with E.chilensis/E.albidiflora exhibiting traits that promote reproductive isolation from E.litoralis,supporting a scenario of rapid speciation occurring within the past half of million years in the absence of geographic barriers.These findings underscore the pivotal role of pollinator interactions in shaping angiosperm speciation and biodiversity,highlighting their dynamic influence on ecological and evolutionary processes.
基金supported by Agencia Nacional de Investigación y Desarrollo(ANID),Chilean Government Fondecyt Regular 1211480supported by a Master ANID Scholarship+1 种基金funded by ANID/Fondecyt Regular 1211480funded by EQM150061(FONDEQUIP-ANID)。
文摘Oral squamous cell carcinoma(OSCC)is the most common manifestation of oral cancer.It has been proposed that periodontal pathogens contribute to OSCC progression,mainly by their virulence factors.However,the main periodontal pathogen and its mechanism to modulate OSCC cells remains not fully understood.In this study we investigate the main host-pathogen pathways in OSCC by computational proteomics and the mechanism behind cancer progression by the oral microbiome.The main hostpathogen pathways were analyzed in the secretome of biopsies from patients with OSCC and healthy controls by mass spectrometry.Then,functional assays were performed to evaluate the host-pathogen pathways highlighted in oral cancer.Host proteins associated with LPS response,cell migration/adhesion,and metabolism of amino acids were significantly upregulated in the human cancer proteome,whereas the complement cascade was downregulated in malignant samples.Then,the microbiome analysis revealed large number and variety of peptides from Fusobacterium nucleatum(F.nucleatum)in OSCC samples,from which several enzymes from the L-glutamate degradation pathway were found,indicating that L-glutamate from cancer cells is used as an energy source,and catabolized into butyrate by the bacteria.In fact,we observed that F.nucleatum modulates the cystine/glutamate antiporter in an OSCC cell line by increasing SLC7A11 expression,promoting L-glutamate efflux and favoring bacterial infection.Finally,our results showed that F.nucleatum and its metabolic derivates promote tumor spheroids growth,spheroidsderived cell detachment,epithelial-mesenchymal transition and Galectin-9 upregulation.Altogether,F.nucleatum promotes protumoral mechanism in oral cancer.
基金supported by Fondecyt 1200908(to JF)the Conicyt 21141247(to JDP)。
文摘The onset and mechanisms underlying neurodegenerative diseases remain uncertain. The main features of neurodegenerative diseases have been related with cellular and molecular events like neuronal loss, mitochondrial dysfunction and aberrant accumulation of misfolded proteins or peptides in specific areas of the brain. The most prevalent neurodegenerative diseases belonging to age-related pathologies are Alzheimer's disease, Huntington's disease, Parkinson's disease and amyotrophic lateral sclerosis. Interestingly, mitochondrial dysfunction has been observed to occur during the early onset of several neuropathological events associated to neurodegenerative diseases. The master regulator of mitochondrial quality control and energetic metabolism is the transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator 1-alpha(PGC-1α). Additionally, it has been observed that PGC-1α appears to be a key factor in maintaining neuronal survival and synaptic transmission. In fact, PGC-1α downregulation in different brain areas(hippocampus, substantia nigra, cortex, striatum and spinal cord) that occurs in function of neurological damage including oxidative stress, neuronal loss, and motor disorders has been seen in several animal and cellular models of neurodegenerative diseases. Current evidence indicates that PGC-1α upregulation may serve as a potent therapeutic approach against development and progression of neuronal damage. Remarkably, increasing evidence shows that PGC-1α deficient mice have neurodegenerative diseases-like features, as well as neurological abnormalities. Finally, we discuss recent studies showing novel specific PGC-1α isoforms in the central nervous system that appear to exert a key role in the age of onset of neurodegenerative diseases and have a neuroprotective function in the central nervous system, thus opening a new molecular strategy for treatment of neurodegenerative diseases. The purpose of this review is to provide an up-to-date overview of the PGC-1α role in the physiopathology of neurodegenerative diseases, as well as establish the importance of PGC-1α function in synaptic transmission and neuronal survival.
基金financial supported by the the Corporación Nacional Forestal(CONAF)(Project 025/2012‘‘Desarrollo de herramientas de cuantificación biométrica generalizadas para el manejo y uso integral sustentable de renovales de Nothofagus spp.’’)Ⅲ Concurso del Fondo de Investigación del Bosque Nativo
文摘Variable-top stem biomass models at the tree level for second growth forests of roble (Nothofagus obliqua), rauli(Nothofagus alpina), and coigüe (Nothofagus dombeyi) were fitted by a simultaneous density-integral system, which combines a stem taper model and a wood basic density model. For each model, an autoregressive structure of order 2 and a power equation of residual variance were incorporated to reduce residual autocorrelation and heteroscedasticity, respectively. By using dummy variables in the regression analysis, zonal effects on the parameters in the variable-top stem biomass equations were detected in roble. Consequently, equations for clusters of zones were obtained. These equations presented significant parameters and a high precision in both fitting and validation processes (i.e., CV<11.5% and CVp<11.9%, respectively), demonstrating that they are unbiased. The advantage of these types of functions is that they provide estimates of volume and biomass of sections of the stem, defined between any two points of the stem in the three species. Thus, depending on the final use of the wood and the dimensions of the tree, a stem fraction can be quantified in units of volume and the remaining fraction in units of weight.
文摘This study evaluated the expression of defense compounds from the secondary metabolism of Eucalyptus globulus plants, subjected to direct and indirect stimuli by the insect Ctenarytaina eucalypti (blue gum Psyllid). Results showed that defense responses were activated in plants in all tested cases. Were detected and identified thirty-two compounds in the leaves of treated plants, of which five compounds differed with the control, and all are part of the chemical defenses from the plants, three of them were oxygenated monoterpenes (borneol, exo-2-hydroxy cineole and thymol), a aromatic carboxylic acid (benzoic acid) and a quinone (6-acethyl-flaviolin). The plants induced by volatile compounds and by indirect entomological manner, showed its capability to synthesize defensive compounds without a wound that promotes these responses. Were also found some constitutive secondary metabolites over expressed in the different inductions compared with the control.
基金Supported by the Direction of Research of the University of La Serena-Chile (220-2-05 and 220-2-21)the National Council for Scientific and Technological Research,CONICYT (FONDECYT 3020020)
文摘In this study,three semipredictive activity coefficient models:Wilson,non-random-two liquid model(NRTL),and universal quasi-chemical model(UNIQUAC),have been used for modeling vapor-liquid equilibrium properties of ternary mixtures that include substances found in alcoholic distillation processes of wine and musts.In particular,vapor-liquid equilibrium in ternary mixtures containing water + ethanol + congener has been modeled using parameters obtained from binary and ternary mixture data.The congeners are substances that although present in very low concentrations,of the order of part per million,are important enological parameters.The results given by these different models have been compared with literature data and conclusions about the accuracy of the models studied are drawn,recommending the best models for correlating and predicting phase equilibrium properties of this type of mixtures.
基金sponsored (in part) by the Chinese Academy of Sciences (CAS) through a grant to the CAS South America Center for Astronomy (CASSACA) in Santiago, Chile。
文摘Estimating and identifying friction are important aspects of simulating a mechanical drive system. Accurate friction modeling helps to improve a telescope's performance. However, the friction conditions inside are complex and hard to measure. We did simulations with mathematical transfer functions for the Leighton 10 m Telescope and employed a polyline model to identify sources of friction. We made a two-stage model for the Leighton 10 m Telescope. Based on measurements of the motor's currents and speeds, we constructed a curve containing the friction information of the transmission elements. We simulated the system using a step function input under many combinations of friction parameters. By comparing simulation results with the measured ones, we determined the various friction components. This model accurately reproduced the telescope performance including the nonlinearities.
基金financial support CONICYT, Fondecyt Grants 3150010 and 1170083
文摘Different La2O3 contents（0, 1, 2, 3, and 5 wt%） were used to prepared La2O3-ZrO2 mixed oxides calcined at 600 ℃ by the sol-gel method. The catalytic activity was measured as biodiesel production from canola oil through a transesterification reaction. The characterization results indicate that the La2O3 monolayer formation and extent of basicity of m-ZrO2 have a large influence on biodiesel production.Greater biodiesel conversion（56% at 4 h） was obtained with the 3% La2O3-ZrO2 catalyst in the presence of basic sites and the formation of a monolayer of La2O3. The decrease in the catalytic activity for 5% La2O3-ZrO2 resulted from the loss of active sites on the catalyst because of agglomeration, which was suggested by XPS and the isoelectric point. The kinetic data fit to a pseudo-first order constant, and the largest kinetic constant corresponds to 3% La2O3-ZrO2, currently the largest heterogeneous non-alkaline metal catalyst reported for a transesterification reaction.
基金support provided by Co-mision Nacional de Investigacion Cientifica y Tecnologica(CONICYT),through FONDECYT project 1110 798:“Determinacion de indicadores geograficoambien-tales y de riesgo natural en el paisaje de La Araucania y Los Rios:Herramientas de soporte decisional para la planificacion y gestion territorial en sistemas costeros”.
文摘Coastal zones are very dynamic and fragile environments, constituting a landscape ever more heterogeneous, fragmented and with increasing levels of complexity due to the changing relationship between man and nature. Integrated coastal zone management therefore requires detailed knowledge of the system and its components, based—to a large extent—on technical and scientific information. However, the information generated must be in line with the political requirements necessary for decision-making and planning. Thus the use of indicators to give a simplified view of the many components of the territory, and at the same time to provide important information about patterns or trends, becomes a tool of the utmost importance. These indicators can be understood as measurable characteristics of the environment, which facilitate comprehension of the processes occurring at different scales and serve as a reference to inform the population and support decision-making. The aim of the present note is to demonstrate briefly the need to develop geographical-environmental and natural risk indicators to facilitate comprehension of the dynamic of spatial and temporal landscape patterns, particularly in coastal environments. This approach offers an historical summary of the natural, socio-economic and political processes which currently make up the territory, and which without doubt will continue to influence it in the future. At the same time, it is proposed that information should be integrated on the basis of this framework with a view to generating spatial decision support systems in a context of planning and integrated management of the coastal zones of Chile.
文摘The volatilization kinetics of senarmontite(Sb_(2)O_(3))was analyzed in a neutral atmosphere in two temperature ranges:550-615°C(roasting temperature)and 660-1100°C(melting temperature)by using a thermogravimetric analysis method under various gas flow rates and using a 1.3 m L ceramic crucible(11 mm in internal diameter and 14 mm in height).The effect of particle size was also analyzed.The experimental results of mass loss data,X-ray diffraction(XRD)analysis of partially reacted samples and thermodynamic studies indicate that the senarmontite becomes volatile in the form of Sb_(4)O_(6)(g)without the formation of any intermediary compound in the entire temperature range.At roasting temperatures,the volatilization kinetics of Sb_(2)O_(3) was analyzed using the model X=kappt.The volatilization reaction was controlled by the surface chemical reaction and an activation energy value of 193.0 k J/mol was obtained in this temperature range.Based on the volatilization kinetics at the melting temperatures,for linear behaviour in nitrogen gas,kinetic constants were determined,and an activation energy of 73.9 k J/mol was calculated for the volatilization reaction with a surface area of 8.171×10^(-5)m^(2).
基金Funding for this research was obtained from MINECO(Spain)through the project RTA2014-00007-C03-02Additional funding was derived from the projects AGL2010-22308-C02-01 and AGL2007-66739-C02-01/FOR
文摘Background: Coupling biomass models with nutrient concentrations can provide sound estimations of carbon and nutrient contents, enabling the improvement of carbon and nutrient balance in forest ecosystems. Although nutrient concentrations are often assumed to be constant for some species and specific tree components, at least in mature stands,the concentrations usually vary with age, site index and even with tree density. The main objective of this study was to evaluate the sources of variation in nutrient concentrations in biomass compartments usually removed during harvesting operations, covering a range of species and management conditions: semi-natural forest, conventional forest plantations and short rotation forestry(SRF). Five species(Betula pubescens, Quercus robur, Eucalyptus globulus, Eucalyptus nitens and Populus spp.) and 14 genotypes were considered. A total of 430 trees were sampled in 61 plots to obtain 6 biomass components:leaves, twigs, thin branches, thick branches, bark and wood. Aboveground leafless biomass was pooled together forpoplar.The concentrations of C, N, K, P, Ca, Mg, S, Fe, Mn, Cu, Zn and B were measured and the total biomass of each sampled tree and plot were determined. The data were analysed using boosted regression trees and conventional techniques.Results: The main sources of variation in nutrient concentrations were biomass component > > genotype(species) ≈ age >tree diameter. The concentrations of Ca, Mg and K were most strongly affected by genotype and age. The concentrations of P, K, Ca, Mg, S and Cu in the wood component decreased with age, whereas C concentrations increased, with a trend to reach 50% in the older trees. In the SRF, interamerican poplar and P. trichocarpa genotypes were comparatively more efficient in terms of Ca and K nutrient assimilation index(NAI)(+65-85%) than eucalypts, mainly because leafless biomass can be removed. In the conventional eucalypt plantations(rotation 15 years), debarking the wood at logging(savings of225% of Ca and 254% of Mg for E. globulus) or the use of selected genotypes(savings of 45% of P and 35% of Ca) will provide wood at a relatively lower nutrient cost. Considering all the E. globulus genotypes together, the management for pulp with removal of debarked wood shows NAI values well above(x 1.7-x 3.9) the ones found for poplar or eucalypt SRF and also higher(x 1.6-x4.0) than the ones found for oak and birch managed in medium or long rotations.The annual rates of nutrient removal were low in the native broadleaved species but the rates of available soil nutrients removed were high as compared to poplar or eucalypts. Management of native broadleaved species should consider nutrient stability through selection of the biomass compartments removed.(Continued on next page)(Continued from previous page)Conclusions: The nutrient assimilation index is higher in poplar grown under short rotation forestry management than in the other systems considered. Nutrient management of fast growing eucalyptus plantations could be improved by selecting efficient genotypes and limiting removal of wood. The values of the nutrient assimilation index are lower in the natural stands of native broadleaved species than in the other systems considered.
文摘Postharvest waste and loss of horticultural crops exacerbates the agricultural problems facing humankind and will continue to do so in the next decade.Fruits and vegetables provide us with a vast spectrum of healthful nutrients,and along with ornamentals,enrich our lives with a wide array of pleasant sensory experiences.These commodities are,however,highly perishable.Approximately 33%of the produce that is harvested is never consumed since these products naturally have a short shelf-life,which leads to postharvest loss and waste.This loss,however,could be reduced by breeding new crops that retain desirable traits and accrue less damage over the course of long supply chains.New gene-editing tools promise the rapid and inexpensive production of new varieties of crops with enhanced traits more easily than was previously possible.Our aim in this review is to critically evaluate gene editing as a tool to modify the biological pathways that determine fruit,vegetable,and ornamental quality,especially after storage.We provide brief and accessible overviews of both the CRISPR-Cas9 method and the produce supply chain.Next,we survey the literature of the last 30 years,to catalog genes that control or regulate quality or senescence traits that are"ripe"for gene editing.Finally,we discuss barriers to implementing gene editing for postharvest,from the limitations of experimental methods to international policy.We conclude that in spite of the hurdles that remain,gene editing of produce and ornamentals will likely have a measurable impact on reducing postharvest loss and waste in the next 5-10 years.
基金Partially funded by the research project CONICYT (Inserción de nuevos investigadores en la academia, NO. 79090014) from the Chilean Government
文摘Let K be a complete algebraically closed p-adic field of characteristic zero. We apply results in algebraic geometry and a new Nevanlinna theorem for p-adic meromorphic functions in order to prove results of uniqueness in value sharing prob-lems, both on K and on C. Let P be a polynomial of uniqueness for meromorphic functions in K or C or in an open disk. Let f , g be two transcendental meromorphic functions in the whole field K or in C or meromorphic functions in an open disk of K that are not quotients of bounded analytic functions. We show that if f′P′（ f ） and g′P′（g） share a small function α counting multiplicity, then f=g, provided that the multiplicity order of zeros of P′satisfy certain inequalities. A breakthrough in this pa-per consists of replacing inequalities n≥k＋2 or n≥k＋3 used in previous papers by Hypothesis （G）. In the p-adic context, another consists of giving a lower bound for a sum of q counting functions of zeros with （q-1） times the characteristic function of the considered meromorphic function.
文摘Although the degree of mate competition, given extreme differences in sex ratio, explains much of the pattern of male-biased size dimorphism among diverse taxa, it fails for some species which have potential for intense male competition for mates and yet exhibit little or no sexual size dimorphism （SSD）. This fact suggest that species with low SSD should be express the effect of evolutionary pressure in non-obvious geometrical shape promoted by sex ratio in an evolutionary time scale. To evaluate this hypothesis we used phylogenetic comparative method in a Bayesian framework to investigate the evolution of SSD and the role of sex ratio at inter-specific level in the species of Ceroglossus （Coleoptera： Carabidae）. In our results the proportion farthest from 1：1 is associated with more disparate body shape, even though the entire group has minimum variation in sex ratio, which is an intrinsic life history character of this group considering its phylogenetic conservatism or phylogenetic signal. We suggest that the sex ratio has determined the dimorphism degree during evolution of this group, since both traits have increased or decreased together during the species divergence （i.e. positive phylogenetic correlation： r2=0.85）. We suggest that morphological studies of SSD will benefit from using comparative method with Bayesian approaches to assess the effect of phylogenetic history and its uncertainty. Finally, this will be allow to researchers to quantify the uncertainty of specific evolutionary hypotheses accounting for observed sexual dimorphism patterns.
基金The authors gratefully acknowledge the financial support of Labex Tec21 and Labex Arbre for the thesis funding.This work was also supported by the Franco-Chilean EcosSud Collaborative Program C18E05,ANID PIA/Apoyo CCTE AFB170007 of Universidad de Concepcion.
文摘The reinforcing impact of Lignocellulosic micro and nanofibrillated cellulose(L-MNFCs)obtained from Eucalyp-tus Globulus bark in Urea-Formaldehyde UF adhesive was tested.L-MNFCs were prepared by an environmentally friendly,low-cost process using a combination process involving steam explosion followed by refining and ultra-fine grinding.Obtained L-MNFCs showed a web-like morphology with some aggregates and lignin nanodroplets.They present a mixture of residual fibers and fine elements with a width varying between 5 nm to 20μm,respec-tively.The effects of the addition of low amounts of L-MNFCs(1%wt.)on the properties of three different adhe-sives(Urea-Formaldehyde UF,Phenol-Formaldehyde PF,and Tannin-Hexamine TH)were studied by the evolution of the pH,the viscosity,and the mechanical properties.Results showed that the viscosity of PF and UF adhesives increased with the addition of L-MNFCs,unlike TH.Meanwhile,the addition led to better mechan-ical behavior for the three adhesives.Particleboards were then prepared using modified UF with L-MNFCs and tested.Results showed that an amount of 1%wt.of L-MNFCs was sufficient to increase the internal bonding by≈67%,the modulus of elasticity by≈43%,and the modulus of rupture by≈29%.
基金financially supported by the National Key R&D Program of China(No.2022YFC2903803)National Natural Science Foundation of China(No.52130404)+4 种基金Guangdong Basic and Applied Basic Research Foundation(No.2021A1515110161)ANID(Chile)through Fondecyt project 1210610Centro de Modelamiento Matemático(BASAL funds for Centers of Excellence FB210005)CRHIAM project ANID/FONDAP/15130015Anillo project ANID/ACT210030。
文摘The 3D reconstruction and quantitative characterization of drainage channels and coarse tailings particles in a bed were conducted in this study.The influence of variations in the azimuthal angle(θ)and polar angle(φ)of coarse particles on drainage channel structure was analyzed,and the drainage mechanism of the bed was studied.Results showed that water discharge in the bed reduced the size of pores and throat channels,increasing slurry concentration.The throat channel structure was a key component of the drainage process.Theφandθof particles changed predominantly along the length direction.The changes inφhad a cumulative plugging effect on the drainage channel and increased the difficulty of water discharge.The rake and rod formed a shear ring in the tailings bed with shear,and theθdistribution of particles changed from disorderly to orderly during the rotation process.The drainage channel was squeezed during the shearing process with the change inθ,which broke the channel structure,encouraged water discharge in the bed,and facilitated a further increase in slurry concentration.The findings of this work are expected to offer theoretical guidance for preparing high-concentration underflow in the tailings thickening process.
文摘We searched for long period variation in V-band, It-band and RXTE X-ray light curves of the High Mass X-ray Binaries （HMXBs） LS 1698 / RX J1037.5-5647, HD 110432 / 1H 1249-637 and HD 161103 / RX J1744.7-2713 in an attempt to discover orbitally induced variation. Data were obtained primarily from the ASAS database and were supplemented by shorter term observations made with the 24- and 40-inch ANU telescopes and one of the robotic PROMPT telescopes. Fourier periodograms suggested the existence of long period variation in the V-band light curves of all three HMXBs, however folding the data at those periods did not reveal convincing periodic variation. At this point we cannot rule out the existence of long term V-band variation for these three sources and hints of longer term variation may be seen in the higher precision PROMPT data. Long term V-band observations, on the order of several years, taken at a frequency of at least once per week and with a precision of 0.01 mag, therefore still have a chance of revealing long term variation in these three HMXBs.
基金funded with research grants from projects of UNLP 11N/534,CONICET PID 00916 and PRIN-COFIN 2007grants form the Spanish Ministry of Science and Innovation(Projects CGL2007-63237/BTE)
文摘The collision of a divergent ocean ridge may evolve into two end cases： in the continuity of ocean-floor subduction, or in the detachment of the subducted plate. The northern Patagonia active plate margin has the unique situation that in Cenozoic time it has been subjected to two divergent ridge collisions, each one representing one of the end members. The Neogene Antarctica-Nazca divergent ridge collision evolved as a continuous ocean-floor subduction system, promoting a magmatic hiatus at the arc axis, the obduction of part of the ridge ocean-floor in the fore-arc, and basaltic volcanism in the back-arc. In contrast, the Paleogene Farallon-Aluk divergent ridge collision evolved into a transform margin, with the detachment and sinking of the Aluk plate and the development of a large slab window. As in the previous case, this collision promoted a magmatic hiatus at the arc axis, but the tectono-magmatic scenario changed to postorogenic synextensional volcanism that spread to the former fore-arc （basalt, andesite, rhyolite） and former back-arc （bimodal ignimbrite flare-up, basalt）. Geochemistry of this slab window synextensional volcanism shows more MORB-like basalts towards the former fore-arc, and MORB-OIB-Iike basalts towards the former back-arc. Instead, an isolated undeformable crustal block in the former back-arc, with an ＂epeirogenic＂ response to the slab window and extensional regime, was covered by OIB-type basalts after uplift. Major elements show that slab window basalts reach TiO2 values up to 3 wt%, as compared with the top value of 1.5 wt% of arc magmas. Besides, the MgO with respect to （FeOt ＋ A1203） ratio helps to distinguish slab window magma changes from the former fore-arc to the former back-arc and also with respect to the ＂epeirogenic＂ block. Higher contents of HFS elements such as Nb and Ta also help to distinguish this slab window from arc magmas and also, to distinguish slab window magma changes from the former fore-arc to the former back-arc and ＂epeirogenic＂ block settings. The isotope compositions of slab window magmatism show a disparate coeval array from MORB to crustal sources, interpreted as a consecluence of the lack of protracted storage and homogenization due to the extensional setting.
文摘The monitoring of trees is crucial for the management of large areas of forest cultivations,but this process may be costly.However,remotely sensed data offers a solution to automate this process.In this work,we used two neural network methods named You Only Look Once(YOLO)and Mask R-CNN to overcome the challenging tasks of counting,detecting,and segmenting high dimensional Red–Green–Blue(RGB)images taken from unmanned aerial vehicles(UAVs).We present a processing framework,which is suitable to generate accurate predictions for the aforementioned tasks using a reasonable amount of labeled data.We compared our method using forest stands of different ages and densities.For counting,YOLO overestimates 8.5%of the detected trees on average,whereas Mask R-CNN overestimates a 4.7%of the trees.For the detection task,YOLO obtains a precision of 0.72 and a recall of 0.68 on average,while Mask R-CNN obtains a precision of 0.82 and a recall of 0.80.In segmentation,YOLO overestimates a 13.5%of the predicted area on average,whereas Mask R-CNN overestimates a 9.2%.The proposed methods present a cost-effective solution for forest monitoring using RGB images and have been successfully used to monitor∼146,500 acres of pine cultivations.
