The global reheating observed in these last years is followed with a change of rainfalls bunches at the global and regional area.The floods frequency increasing,dangerously impacts the socio-economic activities of sev...The global reheating observed in these last years is followed with a change of rainfalls bunches at the global and regional area.The floods frequency increasing,dangerously impacts the socio-economic activities of several countries throughout the world.Indeed,for Niger as a country located in West Africa where the majority of the population existence depends on the agricultural and pastoral activities,this change of rainfalls bunches may have unwanted consequences.The aim of this work is to analyze the evolution and trend of rainfall in Niger during the period 2008-2024 compared to the period 1971-2000 characterized by episodes of drought.To achieve the objective of this work,annual data of rainfalls and the number of rainy days from four meteorological stations representative of the four major climatic zones of Niger are used.These are the station of Agadez(in Sahelian zone),the station of Tahoua(in mid Sahelian and Saharan zone),the station of Niamey(in Sahelian zone)and the station of Gaya(in mid Sahelian and Sudden zone).Thus,the standardized index of Lamb(1982)and the least squares method are respectively used to analyze the variability of the interannual rainfalls and their tendency.The results obtained show a significant improvement in rainfall in the four climatic zones compared to the period from 1971 to 2000,and especially in the Nigerien Sahara where 88.2%of the years were wet.The latitudinal gradient South-North of the rainfalls has known an upgrading going from 1 mm/km during the period of 1971-2000 to 1.26 mm/km during the period of 2008-2024.Our results also show that this improvement in rainfall is linked to heavy rainfall events which are the cause of floods observed mainly during wet years(2010,2012,2013,2017,2019 and 2024).Finally,the results show that,excepting the Sahel-Niger,the other climatic zones are experiencing an increasing trend in rainfall.Therefore,in the face of current climate change,West African countries must mobilize to put in place a strategy to mitigate the consequences of heavy rainfall.展开更多
The existing research on rescue robots has focused mainly on reconnaissance,detection,and firefighting,and a small number of robots that can achieve human rescue have problems such as poor safety and stability and ins...The existing research on rescue robots has focused mainly on reconnaissance,detection,and firefighting,and a small number of robots that can achieve human rescue have problems such as poor safety and stability and insufficient carrying capacity.This article addresses the above issues and cleverly combines the advantages of soft robotic arms,underactuated robotic arms,and suction cups based on the principles of bionics.A new design for a robotic arm was proposed,and its working principle was explained.Then,the human rescue process was divided into two stages,and the grasping force of the robotic arm in each stage was analyzed separately.Finally,a prototype of the principle was developed,and the feasibility of the design principle of the robotic arm was verified through grasping experiments on a cross-sectional contour model of the human chest.At the same time,grasping experiments were conducted on different objects to demonstrate the potential application of the robotic arm in grasping ground objects.This research proposes a stress envelope adsorption rescue robot arm inspired by the adhesion ability of the Drosera plant and the stress envelope effect,which can apply force to the entire surface of the human body,reduce local force on the human body,ensure load-bearing capacity and adaptability,and improve the safety and stability of rescue grasping.展开更多
The hydrogen-bonded organic frameworks(HOFs)as a new type of porous framework materials have been widely studied in various areas.However,the lack of appropriate active sites,low intrinsic conductivity,and poor stabil...The hydrogen-bonded organic frameworks(HOFs)as a new type of porous framework materials have been widely studied in various areas.However,the lack of appropriate active sites,low intrinsic conductivity,and poor stability limited their performance in the field of electrocatalysis.Herein,we designed two 2D metal hydrogen-bonded organic frameworks(2D–M–HOF,M=Cu^(2+)or Ni^(2+))with coordination compounds based on 2,3,6,7,14,15-hexahydroxyl cyclotricatechylene and transition metal ions(Cu^(2+)and Ni^(2+)),respectively.The crystal structure of 2D–Cu–HOF is determined by continuous rotation electron diffraction,indicating an undulated 2D hydrogen-bond network with interlayeredπ-πstacking.The flexible structure of 2D–M–HOF leads to the formation of self-adaption interlayered sites,resulting in superior activity and selectivity in the electrocatalytic conversion of CO_(2) to C_(2) products,achieving a total Faradaic efficiency exceeding 80%due to the high-efficiency C–C coupling.The experimental results and density functional calculations verify that the undulated 2D–M–HOF enables the energetically favorable formation of*OCCHO intermediate.This work provides a promising strategy for designing HOF catalysts in electrocatalysis and related processes.展开更多
A hydrotalcite with Mg/AI molar ratio 2 was prepared by co-precipitation method and was characterized by XRD, TG/DTA, Zeta potential and BET surface area. The hydrotalcite was calcined at 500℃, with the dehydration f...A hydrotalcite with Mg/AI molar ratio 2 was prepared by co-precipitation method and was characterized by XRD, TG/DTA, Zeta potential and BET surface area. The hydrotalcite was calcined at 500℃, with the dehydration from interlayer, the dehydroxilation from the brucite-like layer and the decomposition of carbonate successively, transformed into the mixed oxide type. The removal of thiocyanate from aqueous solution by using the original hydrotalcite and calcined hydrotalcite （HTC-500） was investigated. The results showed that the thiocyanate adsorption capacity of calcined hydrotalcite was much higher than that of the original form. Calcined hydrotalcite was particularly effective at removing thiocyanate, and that the effective range of pH for the thiocyanate removal are between 5.5-10.0. The experimental data of thiocyanate removal fit nicely with Langmuir isotherm, and the saturated adsorption uptake was 96.2 mg SCN-/g HTC-500. The adsorption of thiocyanate by calcined hydrotalcite follows first-order kinetics. And the intercalation to the structure recovery for calcined hydrotalcite. But the presence of additional anions could affect the adsorption behavior of thiocyanate.展开更多
Efficient synthesis of transition metal hydroxides on conductive substrate is essential for enhancing their merits in industrialization of energy storage field.However,most of the synthetic routes at present mainly re...Efficient synthesis of transition metal hydroxides on conductive substrate is essential for enhancing their merits in industrialization of energy storage field.However,most of the synthetic routes at present mainly rely on traditional bottom-up method,which involves tedious steps,time-consuming treatments,or additional alkaline media,and is unfavorable for high-efficiency production.Herein,we present a facile,ultrafast and general avenue to synthesize transition metal hydroxides on carbon substrate within 13 s by Joule-heating method.With high reaction kinetics caused by the instantaneous high temperature,seven kinds of transition metal-layered hydroxides(TM-LDHs)are formed on carbon cloth.Therein,the fastest synthesis rate reaches~0.46 cm^(2)s^(-1).Density functional theory calculations further demonstrate the nucleation energy barriers and potential mechanism for the formation of metal-based hydroxides on carbon substrates.This efficient approach avoids the use of extra agents,multiple steps,and long production time and endows the LDHs@carbon cloth with outstanding flexibility and machinability,showing practical advantages in both common and micro-zinc ion-based energy storage devices.To prove its utility,as a cathode in rechargeable aqueous alkaline Zn(micro-)battery,the NiCo LDH@carbon cloth exhibits a high energy density,superior to most transition metal LDH materials reported so far.展开更多
miRNA can regulate development and milk yield of the mammary gland through epigenetic mechanism, miRNA can directly and indirectly modulate the activity of the epigenetic machinery, target genes through post-inhibitio...miRNA can regulate development and milk yield of the mammary gland through epigenetic mechanism, miRNA can directly and indirectly modulate the activity of the epigenetic machinery, target genes through post-inhibition of translation initiation, mediate miRNA decay, target genes and inhibit the positive regulation, regulate tone modification, and regulate DNA methylation of target genes. Here we reviewed the role of miRNAs in mammary gland development and lactation. Researching miRNA in mammary gland development and lactation process, and understanding the response of the epigenetic mechanisms to external stimuli will be an important necessity to devise new technologies for maximizing their activity and milk production in the dairy cow.展开更多
A new method to obtain supercontinuum(SC) source for multiplex coherent anti-stokes Raman scattering (CARS) microscopy is proposed. The nonlinear propagation in photonic-crystal fibers (PCF) of femtosecond pulse laser...A new method to obtain supercontinuum(SC) source for multiplex coherent anti-stokes Raman scattering (CARS) microscopy is proposed. The nonlinear propagation in photonic-crystal fibers (PCF) of femtosecond pulse laser with central wavelength at 800.9 nm is studied with scalar wave theory. Based on the incident laser power and dispersion of PCF, super broadband source for multiplex CARS microscopy is designed.展开更多
BACKGROUND Diabetes distress is an important factor in treatment outcomes and results in poor behavioral and biological consequences.Technology has been used in management programs of diabetes to improve communication...BACKGROUND Diabetes distress is an important factor in treatment outcomes and results in poor behavioral and biological consequences.Technology has been used in management programs of diabetes to improve communication between patients and health care providers and to promote education about the disease and its psychological aspects,which can impact the self-efficacy of the programs.However,the true impact of technological approaches on the management of type 2 diabetes distress remains controversial.AIM To investigate the effectiveness of technology interventions on the management of type 2 diabetes distress.METHODS Studies published from 2014 to 2019 were searched in five databases:MEDLINE,PubMed,Library and Information Science Source,Academic Search Ultimate and PsycINFO.The Boolean logic search terms were:(1)T2Diabetes;(2)diabetes distress;and(3)technology OR mobile OR phone OR application OR web.We also systematically searched the reference lists of the included studies and relevant reviews.Randomized controlled trials with technology interventions,type 2 diabetes patients and diabetes distress as the outcome were selected.The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was followed.RESULTS Of the 88 studies selected,nine full articles met the inclusion criteria and were subjected to final careful review.On the JADAD scale,one article was classified as having poor quality and eight as having good quality.Six out of nine articles showed that technology interventions had a positive impact on diabetes distress scale scores when compared with the initial data.Among the six articles,five showed a greater reduction in the diabetes distress scores from control interventions.Web-based interventions had good results when users received personalized feedback and routine caregiver support and attention.CONCLUSION Technology interventions can contribute positively to the management of type 2 diabetes distress,especially with a tailored approach in conjunction with caregiver interaction with patients.展开更多
In recent years, the advances in terahertz applications have stimulated interest in the biological effects associated with this frequency range. We study the gene expression profile in three types of cells exposed to ...In recent years, the advances in terahertz applications have stimulated interest in the biological effects associated with this frequency range. We study the gene expression profile in three types of cells exposed to terahertz radiation,i.e., human ARPE-19 retinal pigment epithelial cells, simian virus 40-transformed human corneal epithelial cells, and human MIO-M1 Müller cells. We find that the gene expression in response to heat shock is unaffected, indicating that the minimum temperature increases under controlled environment. The transcriptome sequencing survey demonstrates that 6-hour irradiation with a broadband terahertz source results in specific change in gene expression and also the biological functions that are closely related to these genes. Our results imply that the effect of terahertz radiation on gene expression can last over 15 hours and depends on the type of cell.展开更多
A galactopoietic compound, identified as dibutyl phthalate（DBP）, was isolated from Vaccaria segetalis. The activity of DBP on lactation ability of dairy cow mammary gland epithelial cells（DCMECs） cultured in vitro...A galactopoietic compound, identified as dibutyl phthalate（DBP）, was isolated from Vaccaria segetalis. The activity of DBP on lactation ability of dairy cow mammary gland epithelial cells（DCMECs） cultured in vitro and dairy cow was evaluated. Results showed that DBP could promote cell viability, proliferation ability, lactose and β-casein secretion of DCMECs, which could also raise the milk yields of dairy cows significantly.展开更多
In order to invade and adapt to deep-sea environments, shallow-water organisms have to acquire tolerance to high hydrostatic pressure, low water temperature, toxic methane and hydrogen sulfide, and feeding strategies ...In order to invade and adapt to deep-sea environments, shallow-water organisms have to acquire tolerance to high hydrostatic pressure, low water temperature, toxic methane and hydrogen sulfide, and feeding strategies not relying on photosynthetic products. Our previous study showed that the “evolutionary stepping stone hypothe-sis”, which assumes that organic falls can act as stepping-stones to connect shallow sea with deep sea, was supported in Mytilidae. However, it is not known whether other bivalves constituting chemosynthetic communities experienced the same evolutionary process or different processes from mytilid mussels. Therefore, here, we performed phylogenetic analyses by sequencing the nuclear 18S rRNA and mitochondrial COI genes of solemyid and thyasirid bivalves. In Solemyidae, the two genera Solemya and Acharax formed each clade, the latter of which was divided into three subgroups. The Solemya clade and one of the Acharax subgroups diverged in the order of shallow-sea residents, whale-bone residents, and deep-sea vent/seep residents, which supported the “evolutionary stepping stone hypothesis”. Furthermore, in Thyasiridae, the two genera Thyasira and Maorithyas formed a paraphyletic group and the other genera, Adontorhina, Axinopsis, Axinulus, Leptaxinus, and Mendicula, formed a clade. The “evolu-tionary stepping stone hypothesis” was not seemingly supported in the other lineages of Solemyidae and Thyasiridae.展开更多
Drying technology of angiotensin converting enzyme （ACE） inhibitory peptides derived from bovine casein was investigated. No significance was observed on ACE inhibitory activity of products prepared by spay drying a...Drying technology of angiotensin converting enzyme （ACE） inhibitory peptides derived from bovine casein was investigated. No significance was observed on ACE inhibitory activity of products prepared by spay drying and freeze drying （P〉0.05）. Spay drying was the best drying process for practical industry production. The inlet temperature ranged from 140℃ to 160℃ and the exit temperature ranged from 70 ℃ to 90 ℃ during the spay drying process. Under the optimal conditions, scale-up of angiotensin converted enzyme inhibitory peptide from 1 L to 10 L and the experiment was successively conducted. Peptide yield was 29% and half inhibitory concentration （IC50） was 0.53 g. L^-1.展开更多
Transitional metal selenides have high conductivity,even metal quality,which makes them great for using as electrode materials for fabricating supercapacitors.Here,hierarchical Ni_(3)Se_(2)nanosheet-on-nanorods on Ni ...Transitional metal selenides have high conductivity,even metal quality,which makes them great for using as electrode materials for fabricating supercapacitors.Here,hierarchical Ni_(3)Se_(2)nanosheet-on-nanorods on Ni foam(NSR-Ni_(3)Se_(2)/Ni)was fabricated by a facile three-dimensional(3D)substrate-assisted confinement assembly method,and used as a freestanding electrode material for hybrid supercapacitors(HSCs).In this design,metallic Ni_(3)Se_(2)with hybrid 1D/2D architecture could effectively enhance the active specific surface area of electrode and improve space utilization,as well as significantly facilitate electrons transport,while Ni foam served as the Ni source of Ni_(3)Se_(2)and provided 3D multi-electron transport channels,thus boosting the specific capacity.The constructed hierarchical NSR-Ni_(3)Se_(2)electrode delivered a superior areal specific capacity of 1.068 mAh/cm^(2)(7.69 F/cm^(2))at 2 mA/cm^(2)and retained 68.2%of the initial capacity when the current density increases by 15 times.Furthermore,the as-assembled NSR-Ni_(3)Se_(2)device exhibited an ultrahigh energy density of 56.4 Wh/kg and high power density of 4640.3 W/kg,and a capacity retention of 92.6%even after 6000 cycles.展开更多
Nonlinear stability criteria for quasi-geostrophic zonally symmetric flow are improved by establishing an optimal Poincard inequality. The inequality is derived by a variational calculation considering the additional ...Nonlinear stability criteria for quasi-geostrophic zonally symmetric flow are improved by establishing an optimal Poincard inequality. The inequality is derived by a variational calculation considering the additional invariant of zonal momentum. When applied to the Eady model in a periodic channel with finite zonal length, the improved nonlinear stability criterion is identical to the linear normal-mode stability criterion provided the channel meridional width is no greater than 0.8605... times its channel length （which is the geophysically relevant case）.展开更多
To investigate the potential effects of Vaccaria segetalis, we employed the proteomic approach on the dairy cow mammary gland epithelial cells （DCMECs）. A total of 35 differentially expressed nuclear proteins were v...To investigate the potential effects of Vaccaria segetalis, we employed the proteomic approach on the dairy cow mammary gland epithelial cells （DCMECs）. A total of 35 differentially expressed nuclear proteins were visualized by 2-DE and silver nitrate staining. Of these, five proteins also displayed significant expression changes upon treatment of the water decoction from Vaccaria segetalis, and such alterations were further confirmed by RT-PCR. Together, at both the mRNA and protein levels, the water decoction from Vaccaria segetalis increased the expression of proteins ethylmalonic encephalopathy 1 （ETHE1）, vesicle amine transport protein 1 homolog （VAT1）, parkinson disease protein 7 homolog （Protein DJ-1）, proteasome subunit alpha type-2 （PSMA2） and SUMO-activating enzyme subunit 1 （SAE1）. This study would enable a better understanding of the molecular mechanisms underlying this water decoction effects at the protein level.展开更多
Feedstuff intake plays key role in impacting the yield and quality of milk. In this study, we discussed the contents of trace metal elements in cow milk impacted by different feedstuffs. We detected the contents of Pb...Feedstuff intake plays key role in impacting the yield and quality of milk. In this study, we discussed the contents of trace metal elements in cow milk impacted by different feedstuffs. We detected the contents of Pb, Cd, As, Cu, Mg, Ca, Fe and Zn in different feedstuffs and milk by atomic absorption spectrophotometry. The determinations of Pb, Cd and As contents were by graphite furnace A_AS and Cu, Mg, Ca, Fe and Zn was by flame atomic absorption spectrometry. The results showed that Pb, Cd, As and Cu presented in feedstuffs, but Pb, Cd and As were lowly detected in milk samples, and Cu was not detected in milk samples. The content of Mg in concentrates was lower than that in forages. However, the content of Mg in milk from concentrate feed was higher than that in forage feed. This suggested that the utilization of Mg in concentrate feed was higher than that in forage feed. The contents of Ca and Zn were opposite to Mg, and the utilization of Ca and Zn in forage feed was higher than that in concentrate feed. There was no obviously change law of Fe in different feedstuffs and milk samples. The relationship between the contents of trace metal elements in milk to feedstuffs would provide a theoretical basis for dairy farming. It would be useful for improving the milk yield and milk quality of dairy production.展开更多
The shakedown behavior of structures subjected to a combined loading of constant and cyclic loads has been well researched.For some specified problems,shakedown limit loads have been obtained.However,the general effec...The shakedown behavior of structures subjected to a combined loading of constant and cyclic loads has been well researched.For some specified problems,shakedown limit loads have been obtained.However,the general effect of combined loading on the structural shakedown has not yet been presented.The general analytic solution of the elastic shakedown limit load is thus derived for a structure subjected to combined loading.Polizzotto's extended static shakedown theorem for combined loading is applied.The stress field in equilibrium with the external constant load required in Polizzotto's extended theorem is constructed by subtracting the reference elastic stress field of the peak cyclic load from the elastic-plastic stress field of the combined constant load and peak cyclic load.The shakedown condition of the stress field is then derived according to the extended theorem.Through the analytical analysis of the shakedown condition,the structural shakedown behavior under combined loading is investigated.A general solution of the shakedown limit load is then derived,and the effects of the combined loading on the shakedown behavior are proposed.The obtained general analytical result is applied to a hollow tension specimen under constant tension and alternating torsion and a plate with a central hole under constant and cyclic tension.The results are consistent with the solutions reported in the literature.展开更多
The major objective of this study was to determine the effect of corn straw or mixed diet on the small molecule metabolites of liver and milk production of healthy Chinese Holstein cows during lactation.In this study,...The major objective of this study was to determine the effect of corn straw or mixed diet on the small molecule metabolites of liver and milk production of healthy Chinese Holstein cows during lactation.In this study,metabolomic methods based on ultra performance liquid chromatography-mass spectrometry(LC-MS)were used to study the liver metabolites of dairy cows fed on corn straw diet or mixed diet.Ten healthy Chinese Holstein cows were randomly assigned to two groups,under the same management condition,fed different diets respectively,corn straw group(CS)or a mixture of alfalfa hay and Chinese wild rye hay mixed forage group(MF).All the cows were fed for 8 weeks and recorded body weight,dry matter intake,body condition score,fat,protein,lactose,milk yield and the total solids.Livers were sampled from each cow through a liver puncture needle for analysis of a significant difference in small molecule metabolites in cow liver samples from the two different diets.The results suggested that different diet types had significant effects on liver metabolism and milk components in dairy cows.The contents of milk fat,the total solids,milk protein,lactose,dry matter intake(DMI),milk yield,milk protein(%),lactose(%)and milk fat(%)of the corn straw group were significantly lower than those of the mixed forage group(p<0.05);the contents of phosphatidylcholine(PC),histidine,hypoxanthine and mridine in liver tissues of the corn straw group were significantly lower than those in the mixed forage group(p<0.05);acetylcarnitine,uric acid,triacylglycerol(TG),acetal phosphatidylcholine(plasmenyl-PC),acetalphosphatidylethanolamine(plasmenyl-PE)and sphingomyelin(SM)of the corn straw group were significantly higher than those in the mixed forage group(p<0.05).In summary,cows fed on mixed forage diet significantly improved milk yield and lactation performance clearly.展开更多
The main purpose of this study was to determine the effect of a corn straw or mixed diet on milk production, milk composition and the expression of genes associated with lactation in mid-lactation Chinese Holstein cow...The main purpose of this study was to determine the effect of a corn straw or mixed diet on milk production, milk composition and the expression of genes associated with lactation in mid-lactation Chinese Holstein cows. In this study, 10 healthy Chinese Holstein cows were randomly assigned to two groups and fed with different diets respectively, corn straw （CS） or mixed forage （MF） diet. CS group was fed roughage consisting of 53.8% corn straw only and the forge to concentrate （F ： C） ratio [dry matter （DM）] was about 40： 60. MF group was fed roughage consisting of 3.7% Chinese wildrye and 23.4% alfalfa hay, the forge to concentrate （F ： C） ratio （DM） was 70： 30. All the cows were fed 8 weeks and body weight, dry matter intake, body condition score, fat, protein, lactose, milk yield, total solid and somatic cell count （SCC） were recorded. Quantitative real-time PCR （qRT-PCR） was used to analyze cow mammary gland samples representing two different diets. The results suggested that different diet types had significant effects on milk yield, lactose, milk fat, milk protein, dry matter intake and somatic cell count in dairy cows, and cows fed MF diet improved milk production and lactation performance clearly （P〈0.05）. In addition, mRNA expression of genes ACC, roTOR, STATS, CSN2, PPAR）,, FABP3 and PTEN in MF group was extremely significantly higher than that in CS group （P〈0.05）. mRNA expression ofAKT1, FAS, SCD and SREBPlc in MF group was significantly higher than that in CS group （P〈0.01）. In summary, the milk yield and composition in mixed forage group were significantly improved than those in corn straw group.展开更多
Prolactin （PRL） is a versatile signaling molecule and regulates a variety of physiological processes, including mammary gland growth and differentiation and the synthesis of milk proteins. While PRL is known to be n...Prolactin （PRL） is a versatile signaling molecule and regulates a variety of physiological processes, including mammary gland growth and differentiation and the synthesis of milk proteins. While PRL is known to be necessary for high levels of milk protein expression, the mechanism by which the synthesis of milk proteins is stimulated at the transcript level is less known. A major modification in the transcript level is protein phosphorylation. To gain additional insights into the molecular mechanisms at the transcript level underlying PRL action on the dairy cow mammary epithelial cells （DCMECs）, nuclear phosphoproteins whose expression distinguishes proliferating regulated by PRL in DCMECs were identified. A phosphoprotein-enriched fraction from nuclear proteins was obtained by affinity chromatography, and a two-dimensional gel electrophoresis （2-DE） and matrix assisted laser desorption/ionization time of matrix-assisted laser desorption/ionization/time of flight mass spectrometry （MALDI-TOF MS） were used to identify the changes of nuclear phosphoproteins in DCMECs treated with prolactin. Seven proteins displaying~〉2-fold difference in abundance upon PRL treatment in DCMECs were identified by MALDI-TOF MS. The protein-GARS （GlyRS）, which belonged to the class-II aminoacyl-tRNA synthetase family, played a global role in the milk protein synthesis. SERPINH1 （Heat shock protein 47）, which was the first heat shock protein found to be a member of the serpin superfamily, regulated physiologic functions, such as complement activation, programmed cell death, and inflammatory processes. PRDX3, which belonged to a family of antioxidant enzymes, played an important role in scavenging intracellular reactive oxygen species （ROS）. ACTR1A, belonged to the actin family, which was associated with transport of p53 to the nucleus. Annexin A2, a Ca2＋-dependent phospholipid-binding protein, maintained the viability and cell cycle regulation of DCMECs. PSMB2 and PSMD10, which belonged to ubiquitin-proteasome system, were involved in several cellular processes, including cell cycle control, cellular stress response, intracellular signaling. This screening revealed that prolactin influenced the level of nuclear phosphoproteins in DCMECs. This result opens new avenues for the study of the molecular mechanism linked to the synthesis of milk proteins.展开更多
文摘The global reheating observed in these last years is followed with a change of rainfalls bunches at the global and regional area.The floods frequency increasing,dangerously impacts the socio-economic activities of several countries throughout the world.Indeed,for Niger as a country located in West Africa where the majority of the population existence depends on the agricultural and pastoral activities,this change of rainfalls bunches may have unwanted consequences.The aim of this work is to analyze the evolution and trend of rainfall in Niger during the period 2008-2024 compared to the period 1971-2000 characterized by episodes of drought.To achieve the objective of this work,annual data of rainfalls and the number of rainy days from four meteorological stations representative of the four major climatic zones of Niger are used.These are the station of Agadez(in Sahelian zone),the station of Tahoua(in mid Sahelian and Saharan zone),the station of Niamey(in Sahelian zone)and the station of Gaya(in mid Sahelian and Sudden zone).Thus,the standardized index of Lamb(1982)and the least squares method are respectively used to analyze the variability of the interannual rainfalls and their tendency.The results obtained show a significant improvement in rainfall in the four climatic zones compared to the period from 1971 to 2000,and especially in the Nigerien Sahara where 88.2%of the years were wet.The latitudinal gradient South-North of the rainfalls has known an upgrading going from 1 mm/km during the period of 1971-2000 to 1.26 mm/km during the period of 2008-2024.Our results also show that this improvement in rainfall is linked to heavy rainfall events which are the cause of floods observed mainly during wet years(2010,2012,2013,2017,2019 and 2024).Finally,the results show that,excepting the Sahel-Niger,the other climatic zones are experiencing an increasing trend in rainfall.Therefore,in the face of current climate change,West African countries must mobilize to put in place a strategy to mitigate the consequences of heavy rainfall.
基金Supported by National Natural Science Foundation of China(Grant No.52475032)Central Government Guides Local Science and Technology Development Fund Projects(Grant No.246Z2001G)Hebei Provincial Natural Science Foundation Key Projects(Grant No.E2021203125).
文摘The existing research on rescue robots has focused mainly on reconnaissance,detection,and firefighting,and a small number of robots that can achieve human rescue have problems such as poor safety and stability and insufficient carrying capacity.This article addresses the above issues and cleverly combines the advantages of soft robotic arms,underactuated robotic arms,and suction cups based on the principles of bionics.A new design for a robotic arm was proposed,and its working principle was explained.Then,the human rescue process was divided into two stages,and the grasping force of the robotic arm in each stage was analyzed separately.Finally,a prototype of the principle was developed,and the feasibility of the design principle of the robotic arm was verified through grasping experiments on a cross-sectional contour model of the human chest.At the same time,grasping experiments were conducted on different objects to demonstrate the potential application of the robotic arm in grasping ground objects.This research proposes a stress envelope adsorption rescue robot arm inspired by the adhesion ability of the Drosera plant and the stress envelope effect,which can apply force to the entire surface of the human body,reduce local force on the human body,ensure load-bearing capacity and adaptability,and improve the safety and stability of rescue grasping.
基金financially supported by the National Natural Science Foundation of China(nos.21971012,61933002,21601015,21625102,21674012,and 81601549)the National Key Research and Development Program of China(2020YFB1506300)Beijing Institute of Technology Research Fund Program for Young Scholars。
文摘The hydrogen-bonded organic frameworks(HOFs)as a new type of porous framework materials have been widely studied in various areas.However,the lack of appropriate active sites,low intrinsic conductivity,and poor stability limited their performance in the field of electrocatalysis.Herein,we designed two 2D metal hydrogen-bonded organic frameworks(2D–M–HOF,M=Cu^(2+)or Ni^(2+))with coordination compounds based on 2,3,6,7,14,15-hexahydroxyl cyclotricatechylene and transition metal ions(Cu^(2+)and Ni^(2+)),respectively.The crystal structure of 2D–Cu–HOF is determined by continuous rotation electron diffraction,indicating an undulated 2D hydrogen-bond network with interlayeredπ-πstacking.The flexible structure of 2D–M–HOF leads to the formation of self-adaption interlayered sites,resulting in superior activity and selectivity in the electrocatalytic conversion of CO_(2) to C_(2) products,achieving a total Faradaic efficiency exceeding 80%due to the high-efficiency C–C coupling.The experimental results and density functional calculations verify that the undulated 2D–M–HOF enables the energetically favorable formation of*OCCHO intermediate.This work provides a promising strategy for designing HOF catalysts in electrocatalysis and related processes.
文摘A hydrotalcite with Mg/AI molar ratio 2 was prepared by co-precipitation method and was characterized by XRD, TG/DTA, Zeta potential and BET surface area. The hydrotalcite was calcined at 500℃, with the dehydration from interlayer, the dehydroxilation from the brucite-like layer and the decomposition of carbonate successively, transformed into the mixed oxide type. The removal of thiocyanate from aqueous solution by using the original hydrotalcite and calcined hydrotalcite （HTC-500） was investigated. The results showed that the thiocyanate adsorption capacity of calcined hydrotalcite was much higher than that of the original form. Calcined hydrotalcite was particularly effective at removing thiocyanate, and that the effective range of pH for the thiocyanate removal are between 5.5-10.0. The experimental data of thiocyanate removal fit nicely with Langmuir isotherm, and the saturated adsorption uptake was 96.2 mg SCN-/g HTC-500. The adsorption of thiocyanate by calcined hydrotalcite follows first-order kinetics. And the intercalation to the structure recovery for calcined hydrotalcite. But the presence of additional anions could affect the adsorption behavior of thiocyanate.
基金the NSFC(22075019)National Key R&D Program of China(2017YFB1104300)。
文摘Efficient synthesis of transition metal hydroxides on conductive substrate is essential for enhancing their merits in industrialization of energy storage field.However,most of the synthetic routes at present mainly rely on traditional bottom-up method,which involves tedious steps,time-consuming treatments,or additional alkaline media,and is unfavorable for high-efficiency production.Herein,we present a facile,ultrafast and general avenue to synthesize transition metal hydroxides on carbon substrate within 13 s by Joule-heating method.With high reaction kinetics caused by the instantaneous high temperature,seven kinds of transition metal-layered hydroxides(TM-LDHs)are formed on carbon cloth.Therein,the fastest synthesis rate reaches~0.46 cm^(2)s^(-1).Density functional theory calculations further demonstrate the nucleation energy barriers and potential mechanism for the formation of metal-based hydroxides on carbon substrates.This efficient approach avoids the use of extra agents,multiple steps,and long production time and endows the LDHs@carbon cloth with outstanding flexibility and machinability,showing practical advantages in both common and micro-zinc ion-based energy storage devices.To prove its utility,as a cathode in rechargeable aqueous alkaline Zn(micro-)battery,the NiCo LDH@carbon cloth exhibits a high energy density,superior to most transition metal LDH materials reported so far.
基金Support by the Natural Science Foundation of China(31072103)
文摘miRNA can regulate development and milk yield of the mammary gland through epigenetic mechanism, miRNA can directly and indirectly modulate the activity of the epigenetic machinery, target genes through post-inhibition of translation initiation, mediate miRNA decay, target genes and inhibit the positive regulation, regulate tone modification, and regulate DNA methylation of target genes. Here we reviewed the role of miRNAs in mammary gland development and lactation. Researching miRNA in mammary gland development and lactation process, and understanding the response of the epigenetic mechanisms to external stimuli will be an important necessity to devise new technologies for maximizing their activity and milk production in the dairy cow.
基金National Basic Research Program of China(Grant No.2007CB310403)the Nation Natural Science Foundation of China (Grant No. 60772105)+1 种基金Key Program of the Applied Basic Research of Tianjin (Grant No. 07JCZDJC05500)the Doctorate Foundation of the Ministry of Education of China ( Grant No.20030055022)
文摘A new method to obtain supercontinuum(SC) source for multiplex coherent anti-stokes Raman scattering (CARS) microscopy is proposed. The nonlinear propagation in photonic-crystal fibers (PCF) of femtosecond pulse laser with central wavelength at 800.9 nm is studied with scalar wave theory. Based on the incident laser power and dispersion of PCF, super broadband source for multiplex CARS microscopy is designed.
文摘BACKGROUND Diabetes distress is an important factor in treatment outcomes and results in poor behavioral and biological consequences.Technology has been used in management programs of diabetes to improve communication between patients and health care providers and to promote education about the disease and its psychological aspects,which can impact the self-efficacy of the programs.However,the true impact of technological approaches on the management of type 2 diabetes distress remains controversial.AIM To investigate the effectiveness of technology interventions on the management of type 2 diabetes distress.METHODS Studies published from 2014 to 2019 were searched in five databases:MEDLINE,PubMed,Library and Information Science Source,Academic Search Ultimate and PsycINFO.The Boolean logic search terms were:(1)T2Diabetes;(2)diabetes distress;and(3)technology OR mobile OR phone OR application OR web.We also systematically searched the reference lists of the included studies and relevant reviews.Randomized controlled trials with technology interventions,type 2 diabetes patients and diabetes distress as the outcome were selected.The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was followed.RESULTS Of the 88 studies selected,nine full articles met the inclusion criteria and were subjected to final careful review.On the JADAD scale,one article was classified as having poor quality and eight as having good quality.Six out of nine articles showed that technology interventions had a positive impact on diabetes distress scale scores when compared with the initial data.Among the six articles,five showed a greater reduction in the diabetes distress scores from control interventions.Web-based interventions had good results when users received personalized feedback and routine caregiver support and attention.CONCLUSION Technology interventions can contribute positively to the management of type 2 diabetes distress,especially with a tailored approach in conjunction with caregiver interaction with patients.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61675151 and 81570872)the Tianjin Municipal Science and Technology Commission Grants,China(Grant No.15JCYBJC24900)the Clinical Research Foundation of Tianjin Medical University Eye Institute,China(Grant No.16YKJS002)
文摘In recent years, the advances in terahertz applications have stimulated interest in the biological effects associated with this frequency range. We study the gene expression profile in three types of cells exposed to terahertz radiation,i.e., human ARPE-19 retinal pigment epithelial cells, simian virus 40-transformed human corneal epithelial cells, and human MIO-M1 Müller cells. We find that the gene expression in response to heat shock is unaffected, indicating that the minimum temperature increases under controlled environment. The transcriptome sequencing survey demonstrates that 6-hour irradiation with a broadband terahertz source results in specific change in gene expression and also the biological functions that are closely related to these genes. Our results imply that the effect of terahertz radiation on gene expression can last over 15 hours and depends on the type of cell.
基金Supported by "863" Project of Ministry of Science and Technology of China(2013AA102504-03)Talents Foundation of Northeast Agricultural University(2010RCB47,2010RCB55)
文摘A galactopoietic compound, identified as dibutyl phthalate（DBP）, was isolated from Vaccaria segetalis. The activity of DBP on lactation ability of dairy cow mammary gland epithelial cells（DCMECs） cultured in vitro and dairy cow was evaluated. Results showed that DBP could promote cell viability, proliferation ability, lactose and β-casein secretion of DCMECs, which could also raise the milk yields of dairy cows significantly.
文摘In order to invade and adapt to deep-sea environments, shallow-water organisms have to acquire tolerance to high hydrostatic pressure, low water temperature, toxic methane and hydrogen sulfide, and feeding strategies not relying on photosynthetic products. Our previous study showed that the “evolutionary stepping stone hypothe-sis”, which assumes that organic falls can act as stepping-stones to connect shallow sea with deep sea, was supported in Mytilidae. However, it is not known whether other bivalves constituting chemosynthetic communities experienced the same evolutionary process or different processes from mytilid mussels. Therefore, here, we performed phylogenetic analyses by sequencing the nuclear 18S rRNA and mitochondrial COI genes of solemyid and thyasirid bivalves. In Solemyidae, the two genera Solemya and Acharax formed each clade, the latter of which was divided into three subgroups. The Solemya clade and one of the Acharax subgroups diverged in the order of shallow-sea residents, whale-bone residents, and deep-sea vent/seep residents, which supported the “evolutionary stepping stone hypothesis”. Furthermore, in Thyasiridae, the two genera Thyasira and Maorithyas formed a paraphyletic group and the other genera, Adontorhina, Axinopsis, Axinulus, Leptaxinus, and Mendicula, formed a clade. The “evolu-tionary stepping stone hypothesis” was not seemingly supported in the other lineages of Solemyidae and Thyasiridae.
基金Supported by Scientific Research Foundation for Young Scholars of Heilongjiang Province of China (QC07C25)The National High Technology Research and Development Program of China (2008AA10Z315)
文摘Drying technology of angiotensin converting enzyme （ACE） inhibitory peptides derived from bovine casein was investigated. No significance was observed on ACE inhibitory activity of products prepared by spay drying and freeze drying （P〉0.05）. Spay drying was the best drying process for practical industry production. The inlet temperature ranged from 140℃ to 160℃ and the exit temperature ranged from 70 ℃ to 90 ℃ during the spay drying process. Under the optimal conditions, scale-up of angiotensin converted enzyme inhibitory peptide from 1 L to 10 L and the experiment was successively conducted. Peptide yield was 29% and half inhibitory concentration （IC50） was 0.53 g. L^-1.
基金the financial support from the National Key R&D Program of China(Nos.2017YFB1104300 and 2016YFA0200200)National Natural Science Foundation of China(Nos.21575014,21905025,91963113)。
文摘Transitional metal selenides have high conductivity,even metal quality,which makes them great for using as electrode materials for fabricating supercapacitors.Here,hierarchical Ni_(3)Se_(2)nanosheet-on-nanorods on Ni foam(NSR-Ni_(3)Se_(2)/Ni)was fabricated by a facile three-dimensional(3D)substrate-assisted confinement assembly method,and used as a freestanding electrode material for hybrid supercapacitors(HSCs).In this design,metallic Ni_(3)Se_(2)with hybrid 1D/2D architecture could effectively enhance the active specific surface area of electrode and improve space utilization,as well as significantly facilitate electrons transport,while Ni foam served as the Ni source of Ni_(3)Se_(2)and provided 3D multi-electron transport channels,thus boosting the specific capacity.The constructed hierarchical NSR-Ni_(3)Se_(2)electrode delivered a superior areal specific capacity of 1.068 mAh/cm^(2)(7.69 F/cm^(2))at 2 mA/cm^(2)and retained 68.2%of the initial capacity when the current density increases by 15 times.Furthermore,the as-assembled NSR-Ni_(3)Se_(2)device exhibited an ultrahigh energy density of 56.4 Wh/kg and high power density of 4640.3 W/kg,and a capacity retention of 92.6%even after 6000 cycles.
文摘Nonlinear stability criteria for quasi-geostrophic zonally symmetric flow are improved by establishing an optimal Poincard inequality. The inequality is derived by a variational calculation considering the additional invariant of zonal momentum. When applied to the Eady model in a periodic channel with finite zonal length, the improved nonlinear stability criterion is identical to the linear normal-mode stability criterion provided the channel meridional width is no greater than 0.8605... times its channel length （which is the geophysically relevant case）.
基金Supported by Major State Basic Research Development Program of China (973 Program, 2011CB100804)
文摘To investigate the potential effects of Vaccaria segetalis, we employed the proteomic approach on the dairy cow mammary gland epithelial cells （DCMECs）. A total of 35 differentially expressed nuclear proteins were visualized by 2-DE and silver nitrate staining. Of these, five proteins also displayed significant expression changes upon treatment of the water decoction from Vaccaria segetalis, and such alterations were further confirmed by RT-PCR. Together, at both the mRNA and protein levels, the water decoction from Vaccaria segetalis increased the expression of proteins ethylmalonic encephalopathy 1 （ETHE1）, vesicle amine transport protein 1 homolog （VAT1）, parkinson disease protein 7 homolog （Protein DJ-1）, proteasome subunit alpha type-2 （PSMA2） and SUMO-activating enzyme subunit 1 （SAE1）. This study would enable a better understanding of the molecular mechanisms underlying this water decoction effects at the protein level.
文摘Feedstuff intake plays key role in impacting the yield and quality of milk. In this study, we discussed the contents of trace metal elements in cow milk impacted by different feedstuffs. We detected the contents of Pb, Cd, As, Cu, Mg, Ca, Fe and Zn in different feedstuffs and milk by atomic absorption spectrophotometry. The determinations of Pb, Cd and As contents were by graphite furnace A_AS and Cu, Mg, Ca, Fe and Zn was by flame atomic absorption spectrometry. The results showed that Pb, Cd, As and Cu presented in feedstuffs, but Pb, Cd and As were lowly detected in milk samples, and Cu was not detected in milk samples. The content of Mg in concentrates was lower than that in forages. However, the content of Mg in milk from concentrate feed was higher than that in forage feed. This suggested that the utilization of Mg in concentrate feed was higher than that in forage feed. The contents of Ca and Zn were opposite to Mg, and the utilization of Ca and Zn in forage feed was higher than that in concentrate feed. There was no obviously change law of Fe in different feedstuffs and milk samples. The relationship between the contents of trace metal elements in milk to feedstuffs would provide a theoretical basis for dairy farming. It would be useful for improving the milk yield and milk quality of dairy production.
基金Sponsored by the National Natural Science Foundation of China(Grant No.51575474)the College Innovation Team Leader Training Program of Province(Grant No.LJRC012)the Natural Science Foundation of Hebei Province,China(Grant No.E2015203220)
文摘The shakedown behavior of structures subjected to a combined loading of constant and cyclic loads has been well researched.For some specified problems,shakedown limit loads have been obtained.However,the general effect of combined loading on the structural shakedown has not yet been presented.The general analytic solution of the elastic shakedown limit load is thus derived for a structure subjected to combined loading.Polizzotto's extended static shakedown theorem for combined loading is applied.The stress field in equilibrium with the external constant load required in Polizzotto's extended theorem is constructed by subtracting the reference elastic stress field of the peak cyclic load from the elastic-plastic stress field of the combined constant load and peak cyclic load.The shakedown condition of the stress field is then derived according to the extended theorem.Through the analytical analysis of the shakedown condition,the structural shakedown behavior under combined loading is investigated.A general solution of the shakedown limit load is then derived,and the effects of the combined loading on the shakedown behavior are proposed.The obtained general analytical result is applied to a hollow tension specimen under constant tension and alternating torsion and a plate with a central hole under constant and cyclic tension.The results are consistent with the solutions reported in the literature.
基金Supported by the National Natural Science Foundation of China(31101784)Funds for Young Researchers from Northeast Agricultural University(14QC43)。
文摘The major objective of this study was to determine the effect of corn straw or mixed diet on the small molecule metabolites of liver and milk production of healthy Chinese Holstein cows during lactation.In this study,metabolomic methods based on ultra performance liquid chromatography-mass spectrometry(LC-MS)were used to study the liver metabolites of dairy cows fed on corn straw diet or mixed diet.Ten healthy Chinese Holstein cows were randomly assigned to two groups,under the same management condition,fed different diets respectively,corn straw group(CS)or a mixture of alfalfa hay and Chinese wild rye hay mixed forage group(MF).All the cows were fed for 8 weeks and recorded body weight,dry matter intake,body condition score,fat,protein,lactose,milk yield and the total solids.Livers were sampled from each cow through a liver puncture needle for analysis of a significant difference in small molecule metabolites in cow liver samples from the two different diets.The results suggested that different diet types had significant effects on liver metabolism and milk components in dairy cows.The contents of milk fat,the total solids,milk protein,lactose,dry matter intake(DMI),milk yield,milk protein(%),lactose(%)and milk fat(%)of the corn straw group were significantly lower than those of the mixed forage group(p<0.05);the contents of phosphatidylcholine(PC),histidine,hypoxanthine and mridine in liver tissues of the corn straw group were significantly lower than those in the mixed forage group(p<0.05);acetylcarnitine,uric acid,triacylglycerol(TG),acetal phosphatidylcholine(plasmenyl-PC),acetalphosphatidylethanolamine(plasmenyl-PE)and sphingomyelin(SM)of the corn straw group were significantly higher than those in the mixed forage group(p<0.05).In summary,cows fed on mixed forage diet significantly improved milk yield and lactation performance clearly.
基金Supported by Fund of the National Basic Research Program of China(973)(2011CB100804)
文摘The main purpose of this study was to determine the effect of a corn straw or mixed diet on milk production, milk composition and the expression of genes associated with lactation in mid-lactation Chinese Holstein cows. In this study, 10 healthy Chinese Holstein cows were randomly assigned to two groups and fed with different diets respectively, corn straw （CS） or mixed forage （MF） diet. CS group was fed roughage consisting of 53.8% corn straw only and the forge to concentrate （F ： C） ratio [dry matter （DM）] was about 40： 60. MF group was fed roughage consisting of 3.7% Chinese wildrye and 23.4% alfalfa hay, the forge to concentrate （F ： C） ratio （DM） was 70： 30. All the cows were fed 8 weeks and body weight, dry matter intake, body condition score, fat, protein, lactose, milk yield, total solid and somatic cell count （SCC） were recorded. Quantitative real-time PCR （qRT-PCR） was used to analyze cow mammary gland samples representing two different diets. The results suggested that different diet types had significant effects on milk yield, lactose, milk fat, milk protein, dry matter intake and somatic cell count in dairy cows, and cows fed MF diet improved milk production and lactation performance clearly （P〈0.05）. In addition, mRNA expression of genes ACC, roTOR, STATS, CSN2, PPAR）,, FABP3 and PTEN in MF group was extremely significantly higher than that in CS group （P〈0.05）. mRNA expression ofAKT1, FAS, SCD and SREBPlc in MF group was significantly higher than that in CS group （P〈0.01）. In summary, the milk yield and composition in mixed forage group were significantly improved than those in corn straw group.
基金Supported by Major State Basic Research Development Program of China(973 Program,2011CB100804)
文摘Prolactin （PRL） is a versatile signaling molecule and regulates a variety of physiological processes, including mammary gland growth and differentiation and the synthesis of milk proteins. While PRL is known to be necessary for high levels of milk protein expression, the mechanism by which the synthesis of milk proteins is stimulated at the transcript level is less known. A major modification in the transcript level is protein phosphorylation. To gain additional insights into the molecular mechanisms at the transcript level underlying PRL action on the dairy cow mammary epithelial cells （DCMECs）, nuclear phosphoproteins whose expression distinguishes proliferating regulated by PRL in DCMECs were identified. A phosphoprotein-enriched fraction from nuclear proteins was obtained by affinity chromatography, and a two-dimensional gel electrophoresis （2-DE） and matrix assisted laser desorption/ionization time of matrix-assisted laser desorption/ionization/time of flight mass spectrometry （MALDI-TOF MS） were used to identify the changes of nuclear phosphoproteins in DCMECs treated with prolactin. Seven proteins displaying~〉2-fold difference in abundance upon PRL treatment in DCMECs were identified by MALDI-TOF MS. The protein-GARS （GlyRS）, which belonged to the class-II aminoacyl-tRNA synthetase family, played a global role in the milk protein synthesis. SERPINH1 （Heat shock protein 47）, which was the first heat shock protein found to be a member of the serpin superfamily, regulated physiologic functions, such as complement activation, programmed cell death, and inflammatory processes. PRDX3, which belonged to a family of antioxidant enzymes, played an important role in scavenging intracellular reactive oxygen species （ROS）. ACTR1A, belonged to the actin family, which was associated with transport of p53 to the nucleus. Annexin A2, a Ca2＋-dependent phospholipid-binding protein, maintained the viability and cell cycle regulation of DCMECs. PSMB2 and PSMD10, which belonged to ubiquitin-proteasome system, were involved in several cellular processes, including cell cycle control, cellular stress response, intracellular signaling. This screening revealed that prolactin influenced the level of nuclear phosphoproteins in DCMECs. This result opens new avenues for the study of the molecular mechanism linked to the synthesis of milk proteins.
