Biomechanics is a wide interdisciplinary field, which includes all mechanical aspects from living organisms. As traditional erythrocytes viscoelastic analysis is mostly qualitative, the development of new quantitative...Biomechanics is a wide interdisciplinary field, which includes all mechanical aspects from living organisms. As traditional erythrocytes viscoelastic analysis is mostly qualitative, the development of new quantitative methods capable of analyzing at the same time biological and mechanical aspects of the cells in flow, when changing from healthy controls to glucose incubated at different concentrations, is crucial for restricting the subjectivity in the study of the cell behaviour. On the other hand, it is important to appreciate the role of mathematics in the analysis of tissues and cells. Recent developed non linear mathematical methods are particularly fruitful when they are strongly correlated with cells sensitivity to initial conditions. An optic system called Erythrodeformeter has been developed and constructed in our laboratory, in order to evaluate the erythrocytes viscoelastic properties. To analyze the erythrocytes viscoelastic dynamics we used the technique of Time Delay Coordinates suggested by Takens, False Nearest Neighbours proposed by Abarbanel and co-workers, and the forecasting procedure proposed by Sugihara and May, the so called Correlation Coefficient. The results suggest that through this random walk analysis, apparent noise associated with deterministic chaos can be used not only to distinguish but also to characterize at the same time biological and mechanical aspects of the cells in flow, when changing from healthy controls to glucose incubated at different concentrations.展开更多
The article concentrates on the role of fluctuating parameters for removable population from the incubated class in a susceptible-incubated-infected model. The discrete analogous of this model is also investigated. Co...The article concentrates on the role of fluctuating parameters for removable population from the incubated class in a susceptible-incubated-infected model. The discrete analogous of this model is also investigated. Conditions for local asymptotic stability are derived for both the disease free and endemic cases. Numerical simulations are performed to validate the theoretical results.展开更多
An incubation study was conducted in laboratory to determine the effect of lime (L) as CaCO3 and phosphorus (P) as TSP on soil pH and available soil P in an acid soil. Four rates of L equivalent to 0, 1, 2 and 3 ton C...An incubation study was conducted in laboratory to determine the effect of lime (L) as CaCO3 and phosphorus (P) as TSP on soil pH and available soil P in an acid soil. Four rates of L equivalent to 0, 1, 2 and 3 ton CaCO3 ha-1 and four rates of P equivalent to 0, 25, 50 and 75 mg P kg-1 were applied in combinations as treatments. The soil was incubated at field capacity for 8 weeks (wk) after which they were extracted using NaHCO3 (Olsen), Mehlich-3, Kelowna and Bray & Kurtz-1 extractants and soil pH was determined. Lime significantly (P < 0.001) increased soil pH. Phosphorus decreased it, though not significantly. Both L and P had significant effects (P < 0.001) on P availability irrespective of extractants used. Two ton CaCO3 plus 75 mg P kg-1 gave the highest available phosphorus. Mehlich-3 method extracted the largest amount of P (14.54 - 67.35 mg·kg-1) while Olsen extracted the smallest amount (3.25 - 32.77 mg·kg-1). The mean extractable P in soils was found to be in the order of Olsen 2 = 0.87 to 0.95).展开更多
In order to study the influence of difference in C<sub>2</sub>H<sub>2</sub> concentration on the production of CO<sub>2</sub>, N<sub>2</sub>O,NH<sub>4</sub>-...In order to study the influence of difference in C<sub>2</sub>H<sub>2</sub> concentration on the production of CO<sub>2</sub>, N<sub>2</sub>O,NH<sub>4</sub>-N and volatile fatty acids （VFA）, soil slurries with a gradient in C<sub>2</sub>H<sub>2</sub> concentration were anaerobicallyincubated at 25°C for 2 weeks. Acetate, butyrate and CO<sub>2</sub> production and NH<sub>4</sub>-N accumulation wereinhibited in the slurries in the presence of C<sub>2</sub>H<sub>2</sub>; and the inhibition effect increased with increasing C<sub>2</sub>H<sub>2</sub>from 0 to 20 kpa in the headspace gas of the incubation bottle. However, N<sub>2</sub>O, isobutyrate and propionateproduction was not obviously different among the slurries amended with C<sub>2</sub>H<sub>2</sub> from 2.5 to 20 kpa. Therefore,the results implied that the C<sub>2</sub>H<sub>2</sub> did not promote the inhibition but only increased the side effect onother microbial processes. The C<sub>2</sub>H<sub>2</sub> of 2.5 kpa was suggested to be the optimum choice for the presentdenitrification study.展开更多
Dissolved organic matter(DOM)is ubiquitous in the environment and plays an important role in global ecosystems.However,our understanding of the evolution and molecular diversity of DOM from different biomass materials...Dissolved organic matter(DOM)is ubiquitous in the environment and plays an important role in global ecosystems.However,our understanding of the evolution and molecular diversity of DOM from different biomass materials and biochar is not enough.Herein,we investigated the changes in DOM from seven biomass and biochar samples over a bio-incubation of 28 days,and explored their contents,and optical,chemical,and molecular characteristics.The results indicated that dissolved organic carbon(DOC)from different sources all exhibited a gradually decreasing trends during the incubation,while the absorbance and aromaticity gradually increased.Biomass DOM was characterized by higher DOC concentrations and a higher degradation rate,whereas biochar DOM had high aromaticity and little variability.Parallel factor analysis results showed that the protein-like fluorescent groups were as only detected in biomass DOM,while the dominant humic-like components were identified in biochar DOM.Additionally,the molecular composition of DOM from different sources was different,and biomass DOM contained more carbohydrate-like and saturated compounds.More sulfur-containing compounds were detected in Ceratophyllum demersum(CD)DOM,which may indicate that the leaching of CD litter was an important source of sulfur-containing species in aquatic environments.Furthermore,biochar DOM had greater aromaticity and a higher degree of oxidation than the corresponding biomass DOM.This study provided a detailed understanding of the molecular diversity of DOM by considering its various sources,and the results are helpful for further understanding their chemical properties and structures.展开更多
Milk-derived extracellular vesicles(EVs)are promising for oral drug delivery,yet different loading methods exhibit distinct impacts on drug encapsulation and membrane integrity.This study demonstrated that sonication ...Milk-derived extracellular vesicles(EVs)are promising for oral drug delivery,yet different loading methods exhibit distinct impacts on drug encapsulation and membrane integrity.This study demonstrated that sonication method achieved high drug encapsulation in commercial milk-derived EVs(S-CM EVs),but impaired EV structure,compromising transcytosis.Incubation method(I-CM EVs)preserved EVs delivery ability,but had low drug loading.Further proteomic and transmembrane studies showed that sonication greatly damaged membrane proteins involved in trans-epithelial transportation,especially endoplasmic reticulum-Golgi pathway.To overcome this dilemma,we generated a hybrid CM EVs(H-CM EVs)by fusing I-CM EVs and S-CM EVs.H-CM EVs demonstrated comparable drug encapsulation to S-CM EVs(56.14%),significantly higher than I-CM EVs(11.92%).Importantly,H-CM EVs could maintain efficient drug delivery capability by restoring membrane fluidity,repairing damaged proteins,and enhancing enzyme resistance of SCM EVs.H-CM EVs exhibited excellent absorption characteristics with 1.85-fold higher of area under the curve and 2.50-fold higher of max plasma concentration than those of SCM EVs.On typeⅠdiabetic mice,orally delivery of insulin loaded H-CM EVs and I-CM EVs showed improved hypoglycemic effects with pharmacological availabilities of 5.15%and 5.31%,which was 1.7-fold higher than that of S-CM EVs(3.00%).This H-CM EVs platform not only achieved high drug loading and maintained functionality for effective oral delivery but also highlighted the significant translational potential for improved clinical outcomes.展开更多
Avian incubation is characterised by the contact between the eggs and the bird's skin to transfer heat to increase egg temperature above ambient conditions. Birds can be attentive to the clutch all of the time or,...Avian incubation is characterised by the contact between the eggs and the bird's skin to transfer heat to increase egg temperature above ambient conditions. Birds can be attentive to the clutch all of the time or, particularly if only one parent incubates, attentiveness may be quite low. Attentiveness is related to egg size with large eggs having high attentiveness, whereas small eggs (<10 g) can have attentiveness ranging from 50% to 100%. Previous studies have suggested that incubation duration is a function of attentiveness albeit for small birds. This study tested the hypothesis that, after controlling for egg size and phylogeny, incubation duration would be a function of attentiveness. Data for 444 bird species representing 24 orders were analysed. Whilst egg mass had a significant relationship with incubation duration, there was no relationship with attentiveness for all of the species or a subset of the passerines. Despite egg temperature drops during an incubation recess, average day-time and night-time temperatures are similar in a range of species. Re-examination of previously reported temperature profiles recorded by dummy eggs over a 24-h period shows that after an incubation recess there seems to be an additional heat flux that raises egg temperature above that seen during night-time periods of constant incubation. The reasons why eggs under intermittent incubation are not considerably cooler than eggs during constant incubation are discussed.展开更多
The brood-parasitic brown-headed cowbird(Molothrus ater)has one of the shortest incubation periods of any bird.Brown-headed cowbird eggs,and those of other avian brood parasites,tend to be more spherical due to their ...The brood-parasitic brown-headed cowbird(Molothrus ater)has one of the shortest incubation periods of any bird.Brown-headed cowbird eggs,and those of other avian brood parasites,tend to be more spherical due to their greater relative width.The traditional explanation for this egg shape is that it,combined with the thicker eggshells,resists host puncture-ejection.However,very few North American hosts of the brownheaded cowbird actually engage in puncture-ejection and therefore wider eggs may instead provide greater contact with a host’s brood patch during incubation,especially in large host nests.We tested whether greater egg width increased mean temperature and reduced temperature variation in brown-headed cowbirds by inserting temperature probes into brown-headed cowbird and house sparrow(Passer domesticus)eggs and placing them into red-winged blackbird(Agelaius phoeniceus)nests.House sparrow eggs are similar in appearance and in length to cowbird eggs,but are not as wide.We found no signifcant relationship between brown-headed cowbird egg width and mean incubation temperature.However,brown-headed cowbird eggs experienced less temperature variation than house sparrow eggs,and within brown-headed cowbird eggs,more spherical eggs experienced less temperature variation when accounting for differences in width.These results suggest that brownheaded cowbirds may have short incubation periods in part because their eggs exhibit less temperature variation over the course of incubation.The brown-headed cowbird’s egg shape may contribute to its accelerated embryonic development rate relative to host eggs of similar size,which explains its ability to hatch in a variety of host nests.展开更多
Objective:To assess the biological characteristics of human spermatozoa at room temperature(RT,25℃)and 37℃at different time intervals(0,0.5,2,and 24 h)post liquefaction.Methods:Twenty oligoasthenoteratozoospermic sa...Objective:To assess the biological characteristics of human spermatozoa at room temperature(RT,25℃)and 37℃at different time intervals(0,0.5,2,and 24 h)post liquefaction.Methods:Twenty oligoasthenoteratozoospermic samples after liquefaction were incubated at 37℃or RT.Incubation was performed at 4 interval times of 0(after liquefaction),0.5,2,and 24 h.The samples were evaluated for sperm parameters,DNA fragmentation,acrosome reaction,mitochondrial integrity,and lipid peroxidation,at each time interval.Results:After 0.5 h of incubation at RT and 37℃,there were slight variations in sperm viability,normal morphology and DNA fragmentation.Similarly,mitochondrial integrity,acrosome reaction and lipid peroxidation exhibited slight differences following incubation at 0.5 h at both RT and 37℃.In addition,the assessed parameters were mostly damaged at 24 h of incubation.The results confirmed that incubation at 37℃was better than RT in terms of parameters and sperm functional tests,but the difference was not significant.Conclusions:Incubation of oligoasthenoteratozoospermic samples should be done within 0.5 h to minimize the destructive effects of prolonged incubation time(e.g.24 h)on general and specific sperm parameters.The findings declared that incubation temperature of 37℃is safer than RT on the biological characteristics of oligoasthenoteratozoospermic processed spermatozoa.展开更多
The geogenic enrichment of arsenic(As)extensively occurred in the riverine systems from the Qinghai-Tibetan Plateau under active geothermal discharge and chemical weathering conditions,while little is known about how ...The geogenic enrichment of arsenic(As)extensively occurred in the riverine systems from the Qinghai-Tibetan Plateau under active geothermal discharge and chemical weathering conditions,while little is known about how dissolved organic matter(DOM)transformation regulates the aquatic As concentrations.The present study revealed that the DOM components from the Singe Tsangpo River(STR)basin primarily consisted of protein-like components(81.30%±6.48%),with the microbially-endogenous production being a predominant source under the control of temperature and glacier-runoff recharge along the river flow path.Notably,the chemical weathering processes have significantly facilitated the enhancement of humic-like components in the river water.Besides,the groundwater DOM characteristics were predominantly influenced by the mobilization of sedimentary organic matter and the introduction of allochthonous DOM resulting from surface-water recharge.Interestingly,humic-like components facilitated As enrichment through complexation and competitive adsorption effects in both surface water and groundwater under oxidizing conditions,whichwas supported by the significant positive correlations between As and humiclike component(R^(2)=0.31/0.65,P<0.05/0.01)and the concurrent mobilization of As and humic-like components from sediment incubation experiments.Moreover,the Structural Equation Modeling analysis revealed a stronger contribution of humic-like components to the As enrichment in the groundwater compared with surface water,possibly due to the relatively strongermicrobial activity and enhanced mobilization of humic-like components in alluvial aquifers.The present study thus provided new insights into the transformation of DOM and its important role in facilitating As enrichment in the aquatic environment from alpine river basins.展开更多
Soil mineralized nitrogen(N)is a vital component of soil N supply capacity and an important N source for rice growth.Unveiling N mineralization(Nm)process characteristics and developing a simple and effective approach...Soil mineralized nitrogen(N)is a vital component of soil N supply capacity and an important N source for rice growth.Unveiling N mineralization(Nm)process characteristics and developing a simple and effective approach to evaluate soil Nm are imperative to guide N fertilizer application and enhance its efficiency in various paddy soils with different physicochemical properties.Soil properties are important driving factors contributing to soil Nm differences and must be considered to achieve effective N management.Nevertheless,discrepancies in Nm capacity and other key influencing factors remain uncertain.To address this knowledge gap,this study collected 52 paddy soil samples from Taihu Lake Basin,China,which possess vastly different physicochemical properties.The samples were subjected to a 112-d submerged anaerobic incubation experiment at a constant temperature to obtain the soil Nm characteristics.Reaction kinetics models,including one-pool exponential model,two-pool exponential model,and effective cumulative temperature model,were employed to compare characteristic differences between Nm potential(Nmp)and short-term accumulated mineralized N(Amn)processes in relation to soil physicochemical properties.Based on these relationships,simplified Nmp prediction methods for paddy soils were established.The results revealed that the Nmp values were 145.18,88.64,and 21.03 mg kg-1 in paddy soils with pH<6.50,6.50≤pH≤7.50,and pH>7.50,respectively.Significantly,short-term Amn at day 14 showed a good correlation(P<0.01)with Nmp(R2=0.94),indicating that the prevailing short-term incubation experiment is an acceptable marker for Nmp.Moreover,Nmp correlated well with the ultraviolet absorbance value at 260 nm based on NaHCO3 extraction(Na260),further streamlining the Nmp estimation method.The incorporation of easily obtainable soil properties,including pH,total N(TN),and the ratio of total organic carbon to TN(C/N),alongside Na260 for Nmp evaluation allowed the multiple regression model,Nmp=58.62×TN-23.18×pH+13.08×C/N+86.96×Na260,to achieve a high prediction accuracy(R2=0.95).The reliability of this prediction was further validated with published data of paddy soils in the same region and other rice regions,demonstrating the regional applicability and prospects of this model.This study underscored the roles of soil properties in Nm characteristics and mechanisms and established a site-specific prediction model based on rapid extractions and edaphic properties of paddy soils,paving the way for developing rapid and precise Nm prediction models.展开更多
The Agrobacterium-mediated transient expression system with conventional binary vectors is well established in tobacco leaves,while the same system applied to tomato leaflets has relatively low expression efficiency.H...The Agrobacterium-mediated transient expression system with conventional binary vectors is well established in tobacco leaves,while the same system applied to tomato leaflets has relatively low expression efficiency.However,impacts of the leaf age,inoculation method and incubation condition after Agrobacterium infiltration on transient protein expression efficiency are seldom investigated.In this study,we optimize Agrobacterium-mediated transient expression system using conventional binary vectors to achieve the high efficiency of target gene expression in tomato leaflets.We transiently express GFP and a nucleus-localized gene SlUVI4 fused with GFP in detached 10-,20-,and 30-day-old leaflets.The cutting points of leaflets are embedded in MS medium after the Agrobacterium-mediated vacuum infiltration,and all leaflets are kept in the dark before use.The 10-and 30-day-old leaflets have more damage than 20-day-old leaflets after the infiltration.展开更多
Growth indicators including weight, body length, wings length, tail length, tarsus, gape, the third toe and head width of 21 nestlings of Great Bustard (Otis tarda) were measured and investigated in Harbin Zoo, Harbin...Growth indicators including weight, body length, wings length, tail length, tarsus, gape, the third toe and head width of 21 nestlings of Great Bustard (Otis tarda) were measured and investigated in Harbin Zoo, Harbin, China during 1999-2002, and methods on successfully fostering nestlings of the bird were also summarized in this article. The results showed: the Great Bustard is a kind of premature bird and its birth weight was 86.31?.56g (N=21); environmental temperature for the neonatal nestlings should be controlled at 36C; the feeding principle having many meals but little food at each for the nestlings should be followed; since six weeks after birth, nestlings of both gender began to show significant difference in body weight, the weight of male was 1.8 times of that of the female after fourteenth week, and by weight and body figure sexual identity could be easily discerned when 3 or 4 months old; There is no significant difference in growth and development of all organs between male and female nestlings and organ growth curves were fit into Logistic equation.展开更多
[Objective] This study aimed to investigate the effects of temperature on determination of protein concentration with Coomassie Brilliant Blue method,thus proving advice and guidance for accurate determination of prot...[Objective] This study aimed to investigate the effects of temperature on determination of protein concentration with Coomassie Brilliant Blue method,thus proving advice and guidance for accurate determination of protein concentration.[Method] With Coomassie Brilliant Blue method,the concentrations of different bovine serum albumin samples were determined under different temperatures and incubation time.[Result] According to the standard curve,when the determination range of protein concentration was 0-100 mg/ml,the determined protein concentration was relatively stable after incubation at 20 ℃ for 20-30 min.Furthermore,the determination result of higher protein concentration with Coomassie Brilliant Blue method was less affected by various factors.[Conclusion] In determination of protein concentration with Coomassie Brilliant Blue method,temperature,sample concentration and incubation time were important factors affecting the accuracy of experimental results.展开更多
The incubation layer with amorphous structure between the substrate and crystalline layer may obviously affect the performance for a microcrystalline Si thin film transistor (μc-Si TFT),especially for the bottom gate...The incubation layer with amorphous structure between the substrate and crystalline layer may obviously affect the performance for a microcrystalline Si thin film transistor (μc-Si TFT),especially for the bottom gate TFT(BG-TFT).It is found that decreasing the ratio of SiH 4/(H 2+SiH 4) is an effective way to decrease the incubation layer thickness of μc-Si directly deposited by VHF PECVD without any further thermal or laser treatment.Based on the μc-Si with a thin incubation layer,the BG-TFT with Al/SiN x/μc-Si/n+-μc-Si/Al structure is fabricated.The ratio of on-state current to off-state current is up to 106,the mobility is around 0.7cm2/(V·s),and the threshold voltage is about 5V.展开更多
The early precipitation process of Ni（75）Al（14）Mo（11） alloy was simulated by microscopic phase-field model at different temperatures.The microstructure of the alloy,the precipitation time of Llo structure and oc...The early precipitation process of Ni（75）Al（14）Mo（11） alloy was simulated by microscopic phase-field model at different temperatures.The microstructure of the alloy,the precipitation time of Llo structure and occupation probability of the three kinds of atoms were investigated.It is indicated that the non-stoichiometric Ll0（Ⅰ/Ⅱ） phases are found in the precipitation process.With the temperature increasing,the appearance time of Ll0 is brought forward.The Ll0（Ⅱ） structure always precipitates earlier than the Ll0（Ⅰ） structure.Compared with lower temperature,higher temperature brings the formation time of Ll0 phase forward and makes Ll0 phase have a higher order degree.But lower temperature shortens the process time of the Ll0 phase to the Ll2 phase.Al and Mo atoms tend to occupy γ site,Ni atom tends to occupy a and β sites.At the same temperature,Al atom has stronger occupation ability than Mo atom in the same site.Ni,Al and Mo collectively form the composited Ll2 structure.展开更多
In order to investigate the effect of temperature on hatching result of fertilized peacock eggs, they were hatched under conditions of varying temperature and constant temperature respectively. The result shows that t...In order to investigate the effect of temperature on hatching result of fertilized peacock eggs, they were hatched under conditions of varying temperature and constant temperature respectively. The result shows that the hatching rate in the varying temperature treatment group （Group Ⅰ） is higher than that in the constant temperature treatment group （Group Ⅱ）. It suggests that the varying temperature treatment （high temperature in the early period, medium temperature in the middle period, slightly lower temperature in the late period, and slightly higher temperature in the hulling period） is in line with the optimum temperature variation in the hatching of fertilized peacock eggs, contributing the hatching of fertilized peacock eggs.展开更多
An efficient method has been developed for the synthesis of a series of（20R）-panaxadiol derivatives（4a–w） using a continuous-flow microreactor.The antitumor activities of the newly synthesized compounds were eval...An efficient method has been developed for the synthesis of a series of（20R）-panaxadiol derivatives（4a–w） using a continuous-flow microreactor.The antitumor activities of the newly synthesized compounds were evaluated in vitro in two human prostate adenocarcinoma tumor cell lines（i.e.,PC-3and LNCa P cells）,and their cytotoxicities were evaluated using a standard MTT assay.Compounds 4c,4h,4p,4q and 4s exhibited higher antitumor activities toward PC-3 cell line than panaxadiol,which was used as a reference standard.展开更多
[Objective] This study was to investigate the influence of phosphorus （P） fertilizer application on available P and easy-loss P content in red soil under aerobic incubating condition, with the aim to provide theoret...[Objective] This study was to investigate the influence of phosphorus （P） fertilizer application on available P and easy-loss P content in red soil under aerobic incubating condition, with the aim to provide theoretical basis for the management of elemental P and evaluation of elemental P loss potential. [Method] Totally six treat- ments were set to the soil samples. The Olsen-P, Bray-1 P and CaCl2-P contents of each soil sample were measured after indoor aerobic incubation. [Result] In the red soil of different P fertilizer application rates, the Olsen-P content decreased with the increasing of incubation time, while the content of Bray-1 P increased and CaCI2-P content was first increased then decreased. CaCl2-P content was linear correlated with Olsen-P content and Bray-1 P content. About 62% P fertilizers were transformed into Bray-1 P pool, and 14% into Olsen-P pool, but only 0.12% transformed into CaCl2-P pool. [Conclusion] There is little risk of P loss caused by P fertilizer application under aerobic condition, but it would increase with the increasing application dose, and the most serious time is the primeval period after P fertilizer application.展开更多
Objective To observe the effect of C-reactive protein (CRP) on platelet endothelial nitric oxide synthase (eNOS) activity. Methods Peripheral venous blood was collected, platelets were isolated with gel-filtration chr...Objective To observe the effect of C-reactive protein (CRP) on platelet endothelial nitric oxide synthase (eNOS) activity. Methods Peripheral venous blood was collected, platelets were isolated with gel-filtration chromatography and incubated with histamine, L-NAME and different concentrations of CRP(5, 10, 25, 50, 100μg) for 30 min, then eNOS activity was measured as formation of 3H-L-citrulline from 3H-L-arginine. Results展开更多
文摘Biomechanics is a wide interdisciplinary field, which includes all mechanical aspects from living organisms. As traditional erythrocytes viscoelastic analysis is mostly qualitative, the development of new quantitative methods capable of analyzing at the same time biological and mechanical aspects of the cells in flow, when changing from healthy controls to glucose incubated at different concentrations, is crucial for restricting the subjectivity in the study of the cell behaviour. On the other hand, it is important to appreciate the role of mathematics in the analysis of tissues and cells. Recent developed non linear mathematical methods are particularly fruitful when they are strongly correlated with cells sensitivity to initial conditions. An optic system called Erythrodeformeter has been developed and constructed in our laboratory, in order to evaluate the erythrocytes viscoelastic properties. To analyze the erythrocytes viscoelastic dynamics we used the technique of Time Delay Coordinates suggested by Takens, False Nearest Neighbours proposed by Abarbanel and co-workers, and the forecasting procedure proposed by Sugihara and May, the so called Correlation Coefficient. The results suggest that through this random walk analysis, apparent noise associated with deterministic chaos can be used not only to distinguish but also to characterize at the same time biological and mechanical aspects of the cells in flow, when changing from healthy controls to glucose incubated at different concentrations.
文摘The article concentrates on the role of fluctuating parameters for removable population from the incubated class in a susceptible-incubated-infected model. The discrete analogous of this model is also investigated. Conditions for local asymptotic stability are derived for both the disease free and endemic cases. Numerical simulations are performed to validate the theoretical results.
文摘An incubation study was conducted in laboratory to determine the effect of lime (L) as CaCO3 and phosphorus (P) as TSP on soil pH and available soil P in an acid soil. Four rates of L equivalent to 0, 1, 2 and 3 ton CaCO3 ha-1 and four rates of P equivalent to 0, 25, 50 and 75 mg P kg-1 were applied in combinations as treatments. The soil was incubated at field capacity for 8 weeks (wk) after which they were extracted using NaHCO3 (Olsen), Mehlich-3, Kelowna and Bray & Kurtz-1 extractants and soil pH was determined. Lime significantly (P < 0.001) increased soil pH. Phosphorus decreased it, though not significantly. Both L and P had significant effects (P < 0.001) on P availability irrespective of extractants used. Two ton CaCO3 plus 75 mg P kg-1 gave the highest available phosphorus. Mehlich-3 method extracted the largest amount of P (14.54 - 67.35 mg·kg-1) while Olsen extracted the smallest amount (3.25 - 32.77 mg·kg-1). The mean extractable P in soils was found to be in the order of Olsen 2 = 0.87 to 0.95).
文摘In order to study the influence of difference in C<sub>2</sub>H<sub>2</sub> concentration on the production of CO<sub>2</sub>, N<sub>2</sub>O,NH<sub>4</sub>-N and volatile fatty acids （VFA）, soil slurries with a gradient in C<sub>2</sub>H<sub>2</sub> concentration were anaerobicallyincubated at 25°C for 2 weeks. Acetate, butyrate and CO<sub>2</sub> production and NH<sub>4</sub>-N accumulation wereinhibited in the slurries in the presence of C<sub>2</sub>H<sub>2</sub>; and the inhibition effect increased with increasing C<sub>2</sub>H<sub>2</sub>from 0 to 20 kpa in the headspace gas of the incubation bottle. However, N<sub>2</sub>O, isobutyrate and propionateproduction was not obviously different among the slurries amended with C<sub>2</sub>H<sub>2</sub> from 2.5 to 20 kpa. Therefore,the results implied that the C<sub>2</sub>H<sub>2</sub> did not promote the inhibition but only increased the side effect onother microbial processes. The C<sub>2</sub>H<sub>2</sub> of 2.5 kpa was suggested to be the optimum choice for the presentdenitrification study.
基金supported by the National Natural Science Foundation of China(No.42192514)Guangdong Major Project of Basic and Applied Basic Research(No.2023B0303000007)and Guangdong Foundation for Program of Science and Technology Research(No.2023B1212060049)。
文摘Dissolved organic matter(DOM)is ubiquitous in the environment and plays an important role in global ecosystems.However,our understanding of the evolution and molecular diversity of DOM from different biomass materials and biochar is not enough.Herein,we investigated the changes in DOM from seven biomass and biochar samples over a bio-incubation of 28 days,and explored their contents,and optical,chemical,and molecular characteristics.The results indicated that dissolved organic carbon(DOC)from different sources all exhibited a gradually decreasing trends during the incubation,while the absorbance and aromaticity gradually increased.Biomass DOM was characterized by higher DOC concentrations and a higher degradation rate,whereas biochar DOM had high aromaticity and little variability.Parallel factor analysis results showed that the protein-like fluorescent groups were as only detected in biomass DOM,while the dominant humic-like components were identified in biochar DOM.Additionally,the molecular composition of DOM from different sources was different,and biomass DOM contained more carbohydrate-like and saturated compounds.More sulfur-containing compounds were detected in Ceratophyllum demersum(CD)DOM,which may indicate that the leaching of CD litter was an important source of sulfur-containing species in aquatic environments.Furthermore,biochar DOM had greater aromaticity and a higher degree of oxidation than the corresponding biomass DOM.This study provided a detailed understanding of the molecular diversity of DOM by considering its various sources,and the results are helpful for further understanding their chemical properties and structures.
基金financial support from the the Regional Innovation and Development Joint Fund of National Natural Science Foundation of China(grant numbers:U22A20356)the National Key R&D Program of China(No.2021YFE0115200)the National Natural Science Foundation of China(No.81872818).
文摘Milk-derived extracellular vesicles(EVs)are promising for oral drug delivery,yet different loading methods exhibit distinct impacts on drug encapsulation and membrane integrity.This study demonstrated that sonication method achieved high drug encapsulation in commercial milk-derived EVs(S-CM EVs),but impaired EV structure,compromising transcytosis.Incubation method(I-CM EVs)preserved EVs delivery ability,but had low drug loading.Further proteomic and transmembrane studies showed that sonication greatly damaged membrane proteins involved in trans-epithelial transportation,especially endoplasmic reticulum-Golgi pathway.To overcome this dilemma,we generated a hybrid CM EVs(H-CM EVs)by fusing I-CM EVs and S-CM EVs.H-CM EVs demonstrated comparable drug encapsulation to S-CM EVs(56.14%),significantly higher than I-CM EVs(11.92%).Importantly,H-CM EVs could maintain efficient drug delivery capability by restoring membrane fluidity,repairing damaged proteins,and enhancing enzyme resistance of SCM EVs.H-CM EVs exhibited excellent absorption characteristics with 1.85-fold higher of area under the curve and 2.50-fold higher of max plasma concentration than those of SCM EVs.On typeⅠdiabetic mice,orally delivery of insulin loaded H-CM EVs and I-CM EVs showed improved hypoglycemic effects with pharmacological availabilities of 5.15%and 5.31%,which was 1.7-fold higher than that of S-CM EVs(3.00%).This H-CM EVs platform not only achieved high drug loading and maintained functionality for effective oral delivery but also highlighted the significant translational potential for improved clinical outcomes.
文摘Avian incubation is characterised by the contact between the eggs and the bird's skin to transfer heat to increase egg temperature above ambient conditions. Birds can be attentive to the clutch all of the time or, particularly if only one parent incubates, attentiveness may be quite low. Attentiveness is related to egg size with large eggs having high attentiveness, whereas small eggs (<10 g) can have attentiveness ranging from 50% to 100%. Previous studies have suggested that incubation duration is a function of attentiveness albeit for small birds. This study tested the hypothesis that, after controlling for egg size and phylogeny, incubation duration would be a function of attentiveness. Data for 444 bird species representing 24 orders were analysed. Whilst egg mass had a significant relationship with incubation duration, there was no relationship with attentiveness for all of the species or a subset of the passerines. Despite egg temperature drops during an incubation recess, average day-time and night-time temperatures are similar in a range of species. Re-examination of previously reported temperature profiles recorded by dummy eggs over a 24-h period shows that after an incubation recess there seems to be an additional heat flux that raises egg temperature above that seen during night-time periods of constant incubation. The reasons why eggs under intermittent incubation are not considerably cooler than eggs during constant incubation are discussed.
文摘The brood-parasitic brown-headed cowbird(Molothrus ater)has one of the shortest incubation periods of any bird.Brown-headed cowbird eggs,and those of other avian brood parasites,tend to be more spherical due to their greater relative width.The traditional explanation for this egg shape is that it,combined with the thicker eggshells,resists host puncture-ejection.However,very few North American hosts of the brownheaded cowbird actually engage in puncture-ejection and therefore wider eggs may instead provide greater contact with a host’s brood patch during incubation,especially in large host nests.We tested whether greater egg width increased mean temperature and reduced temperature variation in brown-headed cowbirds by inserting temperature probes into brown-headed cowbird and house sparrow(Passer domesticus)eggs and placing them into red-winged blackbird(Agelaius phoeniceus)nests.House sparrow eggs are similar in appearance and in length to cowbird eggs,but are not as wide.We found no signifcant relationship between brown-headed cowbird egg width and mean incubation temperature.However,brown-headed cowbird eggs experienced less temperature variation than house sparrow eggs,and within brown-headed cowbird eggs,more spherical eggs experienced less temperature variation when accounting for differences in width.These results suggest that brownheaded cowbirds may have short incubation periods in part because their eggs exhibit less temperature variation over the course of incubation.The brown-headed cowbird’s egg shape may contribute to its accelerated embryonic development rate relative to host eggs of similar size,which explains its ability to hatch in a variety of host nests.
文摘Objective:To assess the biological characteristics of human spermatozoa at room temperature(RT,25℃)and 37℃at different time intervals(0,0.5,2,and 24 h)post liquefaction.Methods:Twenty oligoasthenoteratozoospermic samples after liquefaction were incubated at 37℃or RT.Incubation was performed at 4 interval times of 0(after liquefaction),0.5,2,and 24 h.The samples were evaluated for sperm parameters,DNA fragmentation,acrosome reaction,mitochondrial integrity,and lipid peroxidation,at each time interval.Results:After 0.5 h of incubation at RT and 37℃,there were slight variations in sperm viability,normal morphology and DNA fragmentation.Similarly,mitochondrial integrity,acrosome reaction and lipid peroxidation exhibited slight differences following incubation at 0.5 h at both RT and 37℃.In addition,the assessed parameters were mostly damaged at 24 h of incubation.The results confirmed that incubation at 37℃was better than RT in terms of parameters and sperm functional tests,but the difference was not significant.Conclusions:Incubation of oligoasthenoteratozoospermic samples should be done within 0.5 h to minimize the destructive effects of prolonged incubation time(e.g.24 h)on general and specific sperm parameters.The findings declared that incubation temperature of 37℃is safer than RT on the biological characteristics of oligoasthenoteratozoospermic processed spermatozoa.
基金supported by the National Natural Science Foundation of China(No.42107094)Sichuan Science and Technology Program(No.2023NSFSC0806)the Geology Bureau project of Xinjiang Uygur Autonomous Region(Nos.XGMB202356 and XGMB202358).
文摘The geogenic enrichment of arsenic(As)extensively occurred in the riverine systems from the Qinghai-Tibetan Plateau under active geothermal discharge and chemical weathering conditions,while little is known about how dissolved organic matter(DOM)transformation regulates the aquatic As concentrations.The present study revealed that the DOM components from the Singe Tsangpo River(STR)basin primarily consisted of protein-like components(81.30%±6.48%),with the microbially-endogenous production being a predominant source under the control of temperature and glacier-runoff recharge along the river flow path.Notably,the chemical weathering processes have significantly facilitated the enhancement of humic-like components in the river water.Besides,the groundwater DOM characteristics were predominantly influenced by the mobilization of sedimentary organic matter and the introduction of allochthonous DOM resulting from surface-water recharge.Interestingly,humic-like components facilitated As enrichment through complexation and competitive adsorption effects in both surface water and groundwater under oxidizing conditions,whichwas supported by the significant positive correlations between As and humiclike component(R^(2)=0.31/0.65,P<0.05/0.01)and the concurrent mobilization of As and humic-like components from sediment incubation experiments.Moreover,the Structural Equation Modeling analysis revealed a stronger contribution of humic-like components to the As enrichment in the groundwater compared with surface water,possibly due to the relatively strongermicrobial activity and enhanced mobilization of humic-like components in alluvial aquifers.The present study thus provided new insights into the transformation of DOM and its important role in facilitating As enrichment in the aquatic environment from alpine river basins.
基金supported by the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.Y201956)the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(No.2023QNRC001)the National Key Research and Development Program of China(No.2017YFD200104).
文摘Soil mineralized nitrogen(N)is a vital component of soil N supply capacity and an important N source for rice growth.Unveiling N mineralization(Nm)process characteristics and developing a simple and effective approach to evaluate soil Nm are imperative to guide N fertilizer application and enhance its efficiency in various paddy soils with different physicochemical properties.Soil properties are important driving factors contributing to soil Nm differences and must be considered to achieve effective N management.Nevertheless,discrepancies in Nm capacity and other key influencing factors remain uncertain.To address this knowledge gap,this study collected 52 paddy soil samples from Taihu Lake Basin,China,which possess vastly different physicochemical properties.The samples were subjected to a 112-d submerged anaerobic incubation experiment at a constant temperature to obtain the soil Nm characteristics.Reaction kinetics models,including one-pool exponential model,two-pool exponential model,and effective cumulative temperature model,were employed to compare characteristic differences between Nm potential(Nmp)and short-term accumulated mineralized N(Amn)processes in relation to soil physicochemical properties.Based on these relationships,simplified Nmp prediction methods for paddy soils were established.The results revealed that the Nmp values were 145.18,88.64,and 21.03 mg kg-1 in paddy soils with pH<6.50,6.50≤pH≤7.50,and pH>7.50,respectively.Significantly,short-term Amn at day 14 showed a good correlation(P<0.01)with Nmp(R2=0.94),indicating that the prevailing short-term incubation experiment is an acceptable marker for Nmp.Moreover,Nmp correlated well with the ultraviolet absorbance value at 260 nm based on NaHCO3 extraction(Na260),further streamlining the Nmp estimation method.The incorporation of easily obtainable soil properties,including pH,total N(TN),and the ratio of total organic carbon to TN(C/N),alongside Na260 for Nmp evaluation allowed the multiple regression model,Nmp=58.62×TN-23.18×pH+13.08×C/N+86.96×Na260,to achieve a high prediction accuracy(R2=0.95).The reliability of this prediction was further validated with published data of paddy soils in the same region and other rice regions,demonstrating the regional applicability and prospects of this model.This study underscored the roles of soil properties in Nm characteristics and mechanisms and established a site-specific prediction model based on rapid extractions and edaphic properties of paddy soils,paving the way for developing rapid and precise Nm prediction models.
基金support of Taishan Scholar Foundation of Shandong Province(tsqn201909073,tsqn201812034)National Natural Science Foundation of China(31872951)。
文摘The Agrobacterium-mediated transient expression system with conventional binary vectors is well established in tobacco leaves,while the same system applied to tomato leaflets has relatively low expression efficiency.However,impacts of the leaf age,inoculation method and incubation condition after Agrobacterium infiltration on transient protein expression efficiency are seldom investigated.In this study,we optimize Agrobacterium-mediated transient expression system using conventional binary vectors to achieve the high efficiency of target gene expression in tomato leaflets.We transiently express GFP and a nucleus-localized gene SlUVI4 fused with GFP in detached 10-,20-,and 30-day-old leaflets.The cutting points of leaflets are embedded in MS medium after the Agrobacterium-mediated vacuum infiltration,and all leaflets are kept in the dark before use.The 10-and 30-day-old leaflets have more damage than 20-day-old leaflets after the infiltration.
文摘Growth indicators including weight, body length, wings length, tail length, tarsus, gape, the third toe and head width of 21 nestlings of Great Bustard (Otis tarda) were measured and investigated in Harbin Zoo, Harbin, China during 1999-2002, and methods on successfully fostering nestlings of the bird were also summarized in this article. The results showed: the Great Bustard is a kind of premature bird and its birth weight was 86.31?.56g (N=21); environmental temperature for the neonatal nestlings should be controlled at 36C; the feeding principle having many meals but little food at each for the nestlings should be followed; since six weeks after birth, nestlings of both gender began to show significant difference in body weight, the weight of male was 1.8 times of that of the female after fourteenth week, and by weight and body figure sexual identity could be easily discerned when 3 or 4 months old; There is no significant difference in growth and development of all organs between male and female nestlings and organ growth curves were fit into Logistic equation.
基金Supported by Natural Science Foundation of Jilin Province(201115221)~~
文摘[Objective] This study aimed to investigate the effects of temperature on determination of protein concentration with Coomassie Brilliant Blue method,thus proving advice and guidance for accurate determination of protein concentration.[Method] With Coomassie Brilliant Blue method,the concentrations of different bovine serum albumin samples were determined under different temperatures and incubation time.[Result] According to the standard curve,when the determination range of protein concentration was 0-100 mg/ml,the determined protein concentration was relatively stable after incubation at 20 ℃ for 20-30 min.Furthermore,the determination result of higher protein concentration with Coomassie Brilliant Blue method was less affected by various factors.[Conclusion] In determination of protein concentration with Coomassie Brilliant Blue method,temperature,sample concentration and incubation time were important factors affecting the accuracy of experimental results.
文摘The incubation layer with amorphous structure between the substrate and crystalline layer may obviously affect the performance for a microcrystalline Si thin film transistor (μc-Si TFT),especially for the bottom gate TFT(BG-TFT).It is found that decreasing the ratio of SiH 4/(H 2+SiH 4) is an effective way to decrease the incubation layer thickness of μc-Si directly deposited by VHF PECVD without any further thermal or laser treatment.Based on the μc-Si with a thin incubation layer,the BG-TFT with Al/SiN x/μc-Si/n+-μc-Si/Al structure is fabricated.The ratio of on-state current to off-state current is up to 106,the mobility is around 0.7cm2/(V·s),and the threshold voltage is about 5V.
基金Project(51275486)supported by the National Natural Science Foundation of China
文摘The early precipitation process of Ni（75）Al（14）Mo（11） alloy was simulated by microscopic phase-field model at different temperatures.The microstructure of the alloy,the precipitation time of Llo structure and occupation probability of the three kinds of atoms were investigated.It is indicated that the non-stoichiometric Ll0（Ⅰ/Ⅱ） phases are found in the precipitation process.With the temperature increasing,the appearance time of Ll0 is brought forward.The Ll0（Ⅱ） structure always precipitates earlier than the Ll0（Ⅰ） structure.Compared with lower temperature,higher temperature brings the formation time of Ll0 phase forward and makes Ll0 phase have a higher order degree.But lower temperature shortens the process time of the Ll0 phase to the Ll2 phase.Al and Mo atoms tend to occupy γ site,Ni atom tends to occupy a and β sites.At the same temperature,Al atom has stronger occupation ability than Mo atom in the same site.Ni,Al and Mo collectively form the composited Ll2 structure.
基金Supported by Scientific and Technological Development General Program of Beijing Municipal Education Commission(KM201412448004)~~
文摘In order to investigate the effect of temperature on hatching result of fertilized peacock eggs, they were hatched under conditions of varying temperature and constant temperature respectively. The result shows that the hatching rate in the varying temperature treatment group （Group Ⅰ） is higher than that in the constant temperature treatment group （Group Ⅱ）. It suggests that the varying temperature treatment （high temperature in the early period, medium temperature in the middle period, slightly lower temperature in the late period, and slightly higher temperature in the hulling period） is in line with the optimum temperature variation in the hatching of fertilized peacock eggs, contributing the hatching of fertilized peacock eggs.
基金supported by the National Natural Science Foundation of China (Nos.81160381 and 81260468)the Natural Science Foundation of Jilin Province (No.201115235)
文摘An efficient method has been developed for the synthesis of a series of（20R）-panaxadiol derivatives（4a–w） using a continuous-flow microreactor.The antitumor activities of the newly synthesized compounds were evaluated in vitro in two human prostate adenocarcinoma tumor cell lines（i.e.,PC-3and LNCa P cells）,and their cytotoxicities were evaluated using a standard MTT assay.Compounds 4c,4h,4p,4q and 4s exhibited higher antitumor activities toward PC-3 cell line than panaxadiol,which was used as a reference standard.
基金Supported by the National Natural Science Foundation of China (41101285)the Research Fund for Young Teachers of Qiongzhou University,China (QYQN201124)~~
文摘[Objective] This study was to investigate the influence of phosphorus （P） fertilizer application on available P and easy-loss P content in red soil under aerobic incubating condition, with the aim to provide theoretical basis for the management of elemental P and evaluation of elemental P loss potential. [Method] Totally six treat- ments were set to the soil samples. The Olsen-P, Bray-1 P and CaCl2-P contents of each soil sample were measured after indoor aerobic incubation. [Result] In the red soil of different P fertilizer application rates, the Olsen-P content decreased with the increasing of incubation time, while the content of Bray-1 P increased and CaCI2-P content was first increased then decreased. CaCl2-P content was linear correlated with Olsen-P content and Bray-1 P content. About 62% P fertilizers were transformed into Bray-1 P pool, and 14% into Olsen-P pool, but only 0.12% transformed into CaCl2-P pool. [Conclusion] There is little risk of P loss caused by P fertilizer application under aerobic condition, but it would increase with the increasing application dose, and the most serious time is the primeval period after P fertilizer application.
文摘Objective To observe the effect of C-reactive protein (CRP) on platelet endothelial nitric oxide synthase (eNOS) activity. Methods Peripheral venous blood was collected, platelets were isolated with gel-filtration chromatography and incubated with histamine, L-NAME and different concentrations of CRP(5, 10, 25, 50, 100μg) for 30 min, then eNOS activity was measured as formation of 3H-L-citrulline from 3H-L-arginine. Results
