Thin walls of an AZ91 magnesium alloy with fine equiaxed grains were fabricated via cold arc-based wire arc additive manufacturing(CA-WAAM),and the droplet transfer behaviours,microstructures,and mechanical properties...Thin walls of an AZ91 magnesium alloy with fine equiaxed grains were fabricated via cold arc-based wire arc additive manufacturing(CA-WAAM),and the droplet transfer behaviours,microstructures,and mechanical properties were investigated.The results showed that the cold arc process reduced splashing at the moment of liquid bridge breakage and effectively shortened the droplet transfer period.The microstructures of the deposited samples exhibited layered characteristics with alternating distributions of coarse and fine grains.During layer-by-layer deposition,the β-phase precipitated and grew preferentially along grain boundaries,while the fineη-Al_(8)Mn_(5)phase was dispersed in the α-Mg matrix.The mechanical properties of the CA-WAAM deposited sample showed isotropic characteristics.The ultimate tensile strength and elongation in the building direction(BD)were 282.7 MPa and 14.2%,respectively.The microhardness values of the deposited parts were relatively uniform,with an average value of HV 69.6.展开更多
Kolbroek pigs have numerous advantages as an indigenous breed including its contributions to food security. However, there are numerous concerns over the current feed regime that compromises its growth performance and...Kolbroek pigs have numerous advantages as an indigenous breed including its contributions to food security. However, there are numerous concerns over the current feed regime that compromises its growth performance and carcass quality. Therefore, this study was conducted to evaluate the growth performance traits, attainment of puberty, backfat thickness (BFT), and carcass traits when boar fed diets supplemented with 10% (standard diet), 13% and 16% crude protein. Fifteen pigs per protein diets were individually housed and fed <em>ad-libitum</em> for eight weeks in a complete randomised design. Average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) were measured on a weekly basis. At the end of the trial, all boars were slaughtered and carcass quality parameters measured. Pearson’s correlation coefficients were calculated between growth performance parameters. Our data revealed that there was an increase in final body weight, ADG, ADFI accompanied by decreases in BFT and the age of attainment of puberty. There was also a positive correlation between ADFI and ADG (r = 0.78) accompanied by a low positive correlation between ADG and BFT (r = 0.12) with a high negative correlation between FCR and ADG (r = -0.94). The water holding capacity (WHC), dressing percentage and marbling mass appeared to decrease while the eye muscle area increased with protein supplementation of the diet. There were also increases in the lungs, liver, small plus large intestines and stomach with no changes in the pancreas and heart tissues. Accompanying these was observations that the meat colour lightness improved accompanied by a decline in meat redness and yellowness. In conclusion, supplementation of boar diet with increasing crude protein improved the carcass quality and growth performance of Kolbroek boars.展开更多
Limited knowledge of the genetic causes of male infertility has resulted in few treatment and targeted therapeutic options. Although the ideal approach to identify infertility causing mutations is to conduct studies i...Limited knowledge of the genetic causes of male infertility has resulted in few treatment and targeted therapeutic options. Although the ideal approach to identify infertility causing mutations is to conduct studies in the human population, this approach has progressed slowly due to the limitations described herein. Given the complexity of male fertility, the entire process cannot be modeled in vitro. As such, animal models, in particular mouse models, provide a valuable alternative for gene identification and experimentation. Since the introduction of molecular biology and recent advances in animal model production, there has been a substantial acceleration in the identification and characterization of genes associated with many diseases, including infertility. Three major types of mouse models are commonly used in biomedical research, including knockoutJknockin/gene-trapped, transgenic and chemical-induced point mutant mice. Using these mouse models, over 400 genes essential for male fertility have been revealed. It has, however, been estimated that thousands of genes are involved in the regulation of the complex process of male fertility, as many such genes remain to be characterized. The current review is by no means a comprehensive list of these mouse models, rather it contains examples of how mouse models have advanced our knowledge of post-natal germ cell development and male fertility regulation.展开更多
Soybean(Glycine max(L.) Merr.) is a non-native and non-staple crop in sub-Saharan Africa(SSA) with potential to be a commercial crop owing to its wide range of uses as food, feed,and industrial raw material. Soybean w...Soybean(Glycine max(L.) Merr.) is a non-native and non-staple crop in sub-Saharan Africa(SSA) with potential to be a commercial crop owing to its wide range of uses as food, feed,and industrial raw material. Soybean was first introduced to SSA by Chinese traders in the19 th century and was cultivated as an economic crop as early as 1903 in South Africa. In the past four decades, soybean cultivation area and production in SSA has increased exponentially, from about 20,000 ha and 13,000 t in the early 1970 s to 1,500,000 ha and2,300,000 t in 2016. Soybean yield has been stagnant in SSA for decades at about 1.1 t ha^(-1),much lower than the world average, representing one of the most challenging issues in the soybean industry in SSA. The low soybean yield in SSA can be attributed to the use of poorperforming varieties and to the limited application of fertilizers and rhizobial inoculants in soils with no history of soybean production. South Africa, Nigeria, Zambia, and Uganda are the leading soybean producers in SSA. Soybean research in SSA is conducted by international and national research institutions, including IITA, national soybean improvement programs, universities, and the private sector. Between 1970 and 2011, 195 soybean varieties were released by IITA, private breeders, and national soybean improvement programs in SSA. This paper reviews the history and current state of soybean production and of the utilization and adoption of tropical varieties in SSA, addresses the major soybean yield-limiting factors across the region, and discusses the potential of the soybean industry in SSA. It also highlights soybean improvement efforts and lessons learned from previous soybean improvement efforts and the current progress of some national soybean improvement programs in SSA. Opportunities for scaling up tropical soybean as a major crop across SSA countries are promising.展开更多
The additive manufacturing(AM)process plays an important role in enabling cross-disciplinary research in engineering and personalised medicine.Commercially available clinical tools currently utilised in radiotherapy a...The additive manufacturing(AM)process plays an important role in enabling cross-disciplinary research in engineering and personalised medicine.Commercially available clinical tools currently utilised in radiotherapy are typically based on traditional manufacturing processes,often leading to non-conformal geometries,time-consuming manufacturing process and high costs.An emerging application explores the design and development of patient-specific clinical tools using AM to optimise treatment outcomes among cancer patients receiving radiation therapy.In this review,we:•highlight the key advantages of AM in radiotherapy where rapid prototyping allows for patient-specific manufacture•explore common clinical workflows involving radiotherapy tools such as bolus,compensators,anthropomorphic phantoms,immobilisers,and brachytherapy moulds;and•investigate how current AM processes are exploited by researchers to achieve patient tissuelike imaging and dose attenuations.Finally,significant AM research opportunities in this space are highlighted for their future advancements in radiotherapy for diagnostic and clinical research applications.展开更多
Electrochemical CO_(2) reduction reaction(CO_(2)RR)is a promising process for reducing CO_(2) emissions and producing high-value chemicals.However,this process remains hindered by diffusion-limited mass transfer,low a...Electrochemical CO_(2) reduction reaction(CO_(2)RR)is a promising process for reducing CO_(2) emissions and producing high-value chemicals.However,this process remains hindered by diffusion-limited mass transfer,low activity,and high overpotentials.Here,we controllably prepared hierarchically porous nitrogen-doped carbon,carbon nanosheets,and carbon nanotubes confined single-atom Fe catalysts for electrochemical CO_(2) reduction.The hierarchically porous Fe-N-C(Fe-HP)exhibited prominent performance with a Faradaic efficiency of CO(FECO)up to 80% and a CO partial current density(jCO)of -5.2 mA·cm^(-2) at -0.5 V vs.reversible hydrogen electrode(RHE),far outperforming the single-atom Fe on N-C nanosheets(Fe-NS)and N-C nanotubes(Fe-NT).The detailed characterizations and kinetic analysis revealed that the hierarchically porous structure accelerated the mass transfer and electron transfer processes toward single-atom Fe sites,promoting the desorption of CO and thereby enhancing CO_(2) reduction efficiency.This study provides a promising approach to designing efficient single-atom catalysts with porous structures for energy conversion applications.展开更多
Broad-spectrum photodetectors(PDs)are essential for various health monitoring,night vision,and telecommunications applications,but their detectivity in a wide absorbance region is limited by undesirable electronic res...Broad-spectrum photodetectors(PDs)are essential for various health monitoring,night vision,and telecommunications applications,but their detectivity in a wide absorbance region is limited by undesirable electronic response properties.Colloidal quantum dots(CQDs)are a promising system for broad-spectrum detection,whereas their practical potential is hindered by suboptimal dark current characteristics.To overcome these challenges,we propose a layered architecture comprising CQDs and a bulk heterojunction(BHJ)organic film as a hole transport layer.The integration of PbS CQDs offers multiple benefits,including bandgap tuning for minimizing thermal carriers,surface passivation to reduce recombination rates,and the formation of high-quality interfaces with organic layers,which collectively contribute to suppressing dark current leakage and thermal excitations by suppressing stray electrons.By integrating ITIC into the BHJ film,the device detectability is significantly enhanced,reaching 1013 Jones in the 400–1000 nm spectral range.This improvement is attributed to the higher lowest unoccupied molecular orbital(LUMO)of ITIC molecules,which effectively hinders electron injection.Additionally,J-aggregation-induced molecular stacking and optimized phase separation of BHJ films contribute to the enhanced performance.The integration of diverse materials offers greater flexibility in device design and functionality,enabling the development of more advanced and sophisticated optoelectronic devices.Furthermore,this approach could significantly enhance the theoretical and practical understanding of optoelectronic device engineering,leading to the development of more advanced optoelectronic devices.展开更多
The CTB Water Wall project is a maximal product life cycle utilization concept study by members of the space architecture design community.Its function is to demonstrate a human space activity Cargo Transport Bag(CTB)...The CTB Water Wall project is a maximal product life cycle utilization concept study by members of the space architecture design community.Its function is to demonstrate a human space activity Cargo Transport Bag(CTB)that becomes a primary water recycling membrane element after delivery of cargo,and then a permanent architectural building block for sustainable space habitation after its use in water treatment is complete.As such,it is intended as an experiment in radical life cycle product optimization in an extremely mass-constrained application environment(human space operations).It also introduces some fundamentally interesting concepts in architectural use of waste materials in extreme environments.Finally,it is in some ways a simple,tactile and visual demonstration of how far sustainable product design can be taken,if the motivation and technical justification are present.展开更多
为改善高氮钢(high-nitrogen steel,HNS)电弧增材过程中出现的力学性能降低、氮逸出等问题,在超音频脉冲熔化极气体保护(ultrasonic frequency pulsed gas metal arc,UFP-GMA)及脉冲熔化极气体保护(pulse gas metal arc,P-GMA)工艺下进...为改善高氮钢(high-nitrogen steel,HNS)电弧增材过程中出现的力学性能降低、氮逸出等问题,在超音频脉冲熔化极气体保护(ultrasonic frequency pulsed gas metal arc,UFP-GMA)及脉冲熔化极气体保护(pulse gas metal arc,P-GMA)工艺下进行高氮钢增材试验,分析超音频脉冲电流对高氮钢增材显微组织及力学性能的影响.研究结果表明,两种工艺方法下高氮钢增材件组织均为树枝晶铁素体及奥氏体基体组成,由于散热方向及温度梯度变化使铁素体组织由长树枝晶变为短树枝晶,生长方向也呈现多向性,叠加超音频脉冲电流后能产生高频振动效应,破碎枝晶,细化晶粒,使界面处树枝晶变为等轴晶;相比于常规脉冲GMA增材工艺,叠加超音频脉冲电流之后力学性能均有所提高,搭接方向抗拉强度为987.1 MPa,提高了7.1%,增材方向抗拉强度为970.6 MPa,提高了6.2%,显微硬度为350.3 HV,两种工艺下断裂模式都呈典型的韧性断裂特征,在韧窝中有第二相析出,为Cr-Mn-Fe氧化物,使Mn元素析出,力学性能下降.展开更多
The onset,cessation,and length of the rainy season are crucial for global water resources,agricultural practices,and food security.However,the response of precipitation seasonality to global warming remains uncertain....The onset,cessation,and length of the rainy season are crucial for global water resources,agricultural practices,and food security.However,the response of precipitation seasonality to global warming remains uncertain.In this study,we analyze how global warming levels(GWLs)of 1.5℃ and 2℃ could affect the timing of rainfall onset(RODs),rainfall cessation(RCDs),and the overall duration of the rainy season(LRS)over global land monsoon(GLM)regions using simulations from CMIP6 under the SSP2-4.5 and SSP5-8.5 scenarios.With high model consensus,our results reveal that RODs are projected to occur later over Southern Africa,North Africa,and South America,but earlier over South Asia and Australia,in a warmer climate.The projected early RODs in Australia are more pronounced at the 2℃ GWL under SSP5-8.5.On the other hand,early RCDs are projected over South America and East Asia,while late RCDs are projected over North Africa,with high inter-model agreement.These changes are associated with a future decrease in LRS in most GLM regions.Additionally,we found that continuous warming over 1.5℃ will further reduce the length of the rainy season,especially over the South America,North Africa,and Southern Africa monsoon regions.The findings underscore the urgent need to mitigate global warming.展开更多
Automated classification of gas flow states in blast furnaces using top-camera imagery typically demands a large volume of labeled data,whose manual annotation is both labor-intensive and cost-prohibitive.To mitigate ...Automated classification of gas flow states in blast furnaces using top-camera imagery typically demands a large volume of labeled data,whose manual annotation is both labor-intensive and cost-prohibitive.To mitigate this challenge,we present an enhanced semi-supervised learning approach based on the Mean Teacher framework,incorporating a novel feature loss module to maximize classification performance with limited labeled samples.The model studies show that the proposed model surpasses both the baseline Mean Teacher model and fully supervised method in accuracy.Specifically,for datasets with 20%,30%,and 40%label ratios,using a single training iteration,the model yields accuracies of 78.61%,82.21%,and 85.2%,respectively,while multiple-cycle training iterations achieves 82.09%,81.97%,and 81.59%,respectively.Furthermore,scenario-specific training schemes are introduced to support diverse deployment need.These findings highlight the potential of the proposed technique in minimizing labeling requirements and advancing intelligent blast furnace diagnostics.展开更多
Ore sorting is a preconcentration technology and can dramatically reduce energy and water usage to improve the sustainability and profitability of a mining operation.In porphyry Cu deposits,Cu is the primary target,wi...Ore sorting is a preconcentration technology and can dramatically reduce energy and water usage to improve the sustainability and profitability of a mining operation.In porphyry Cu deposits,Cu is the primary target,with ores usually containing secondary‘pay’metals such as Au,Mo and gangue elements such as Fe and As.Due to sensing technology limitations,secondary and deleterious materials vary in correlation type and strength with Cu but cannot be detected simultaneously via magnetic resonance(MR)ore sorting.Inferring the relationships between Cu and other elemental abundances is particularly critical for mineral processing.The variations in metal grade relationships occur due to the transition into different geological domains.This raises two questions-how to define these geological domains and how the metal grade relationship is influenced by these geological domains.In this paper,linear relationship is assumed between Cu grade and other metal grades.We applies a Bayesian hierarchical(partial-pooling)model to quantify the linear relationships between Cu,Au,and Fe grades from geochemical bore core data.The hierarchical model was compared with two other models-‘complete-pooling’model and‘nopooling’model.Mining blocks were split based on spatial domain to construct hierarchical model.Geochemical bore core data records metal grades measured from laboratory assay with spatial coordinates of sample location.Two case studies from different porphyry Cu deposits were used to evaluate the performance of the hierarchical model.Markov chain Monte Carlo(MCMC)was used to sample the posterior parameters.Our results show that the Bayesian hierarchical model dramatically reduced the posterior predictive variance for metal grades regression compared to the no-pooling model.In addition,the posterior inference in the hierarchical model is insensitive to the choice of prior.The data is wellrepresented in the posterior which indicates a robust model.The results show that the spatial domain can be successfully utilised for metal grade regression.Uncertainty in estimating the relationship between pay metals and both secondary and gangue elements is quantified and shown to be reduced with partial-pooling.Thus,the proposed Bayesian hierarchical model can offer a reliable and stable way to monitor the relationship between metal grades for ore sorting and other mineral processing options.展开更多
Lateral flow immunoassays(LFIAs)are low-cost,rapid,and easy to use for pointof-care testing(POCT),but the majority of the available LFIA tests are indicative,rather than quantitative,and their sensitivity in antigen t...Lateral flow immunoassays(LFIAs)are low-cost,rapid,and easy to use for pointof-care testing(POCT),but the majority of the available LFIA tests are indicative,rather than quantitative,and their sensitivity in antigen tests are usually limited at the nanogram range,which is primarily due to the passive capillary fluidics through nitrocellulose membranes,often associated with non-specific bindings and high background noise.To overcome this challenge,we report a Beads-on-a-Tip design by replacing nitrocellulose membranes with a pipette tip loaded with magnetic beads.The beads are pre-conjugated with capture antibodies that support a typical sandwich immunoassay.This design enriches the low-abundant antigen proteins and allows an active washing process to significantly reduce non-specific bindings.To further improve the detection sensitivity,we employed upconversion nanoparticles(UCNPs)as luminescent reporters and SARS-CoV-2 spike(S)antigen as a model analyte to benchmark the performance of this design against our previously reported methods.We found that the key to enhance the immunocomplex formation and signal-to-noise ratio lay in optimizing incubation time and the UCNP-to-bead ratio.We therefore successfully demonstrated that the new method can achieve a very large dynamic range from 500 fg/mL to 10μg/mL,across over 7 digits,and a limit of detection of 706 fg/mL,nearly another order of magnitude lower than the best reported LFIA using UCNPs in COVID-19 spike antigen detection.Our system offers a promising solution for ultra-sensitive and quantitative POCT diagnostics.展开更多
Governed by the second law of thermodynamics,waste heat generation is inevitable and has been a major source of energy loss and environmental concern in human society.Harvesting waste heat into useful energy has thus ...Governed by the second law of thermodynamics,waste heat generation is inevitable and has been a major source of energy loss and environmental concern in human society.Harvesting waste heat into useful energy has thus become a paramount priority,but has remained challenging with efficiency and cost constraints.Thermoelectric generators(TEGs),which convert heat into electricity whenever there is a temperature difference,play a crucial role in waste heat harvesting.However,sustaining the temperature difference for uninterrupted and high-power density electricity generation is a major challenge in TEGs to achieve practical applications due to the thermal equilibrium.Here,we demonstrate a diurnal waste heat harvester by integrating a high-power radiative cooling film as the cool end of TEGs to enable a large and continuous temperature difference.Significant voltage increase from 30.0 mV to 65.7 mV was achieved,leading to a dramatic power density enhancement of 4.8 times from 35.2 mW m^(-2)to 168.6 mW m^(-2).In an open zone,an ultra-high power density of 2.76 W m^(-2)was achieved at a heat source temperature of 80°C,exceeding the performance of state-of-the-art radiatively cooled TEGs.More importantly,a portable and foldable thermal energy harvesting prototype composed of 24 TEGs arranged in an array has been constructed.When attached to a hot object(e.g.a car engine hood),it can output 5 V to charge personal electronics(e.g.a cellphone),making it a promising practical device for harvesting waste heat in a wide range of outdoor applications.展开更多
The Lachlan Orogen of New South Wales,Victoria and eastern Tasmania is the best understood element of the eastern Australian Tasmanides.The Tasmanides encompass continental growth in a Neoproterozoic passive margin se...The Lachlan Orogen of New South Wales,Victoria and eastern Tasmania is the best understood element of the eastern Australian Tasmanides.The Tasmanides encompass continental growth in a Neoproterozoic passive margin setting and a Paleozoic–Mesozoic active margin in east Gondwana,bounded to the east by the Pacific Ocean.In the Ordovician,the supra-subduction zone element in the Lachlan Orogen is the Macquarie Arc.This comprises one minor and three major belts of mafic to intermediate volcanic and volcaniclastic rocks,limestones and intrusions that,with two hiatuses in magmatism,span the Ordovician and extend into the Early Silurian.The three major belts in central New South Wales are separated by Silurian–Devonian rift basins and are therefore,inferred to have been rifted apart during crustal extension.Chemical and isotopic data suggest the Macquarie Arc is intraoceanic,developed on primitive oceanic crust.Despite this,key features such as its longevity,stacked magmatic phases,little deformation and flanking coeval craton-derived turbidites and black shales with no provenance mixing indicate differences from modern intraoceanic arcs.Paleogeographic setting and magmatic evolution of the Macquarie Arc provided perfect conditions for mainly porphyry-related,rich Au-Cu deposits,in the Ordovician,and especially in the Early Silurian after amalgamation of the arc with its flanking terranes.展开更多
Mixed halide perovskites exhibit great potential as materials for the future generation of photovoltaic devices.Yet,their reaction to moisture remains uncertain,necessitating further exploration.While prolonged exposu...Mixed halide perovskites exhibit great potential as materials for the future generation of photovoltaic devices.Yet,their reaction to moisture remains uncertain,necessitating further exploration.While prolonged exposure to moisture can lead to degradation,it can also passivate traps at an optimal moisture level.Here,we use scanning probe microscopy to perform nanoscale moisture-dependent photovoltaic characterizations of open and compressed grain boundary(GB)structures of wide bandgap(FAPbI_(3))_(0.3)(FAPbBr_(3))_(0.7) perovskites.The investigation reveals a decrease in the potential barrier at compact GBs with increasing moisture levels,contrasting with the behavior observed in open GBs.Moreover,the photocurrent distribution over both samples proportionally increases when relative humidity(RH)is raised from 10%to 60%.Notably,following a 24-h exposure at RH 60%,the compact-GB sample demonstrates:i)a reduction in the density of charged trap states at GBs,ii)higher photocurrent,accompanied by a noticeable decrease in current hysteresis compared to the open GB sample,and iii)further enhancement in device efficiency and crystallinity compared to devices with open GBs.These findings suggest that optimizing humidity conditions in engineering the GB chemistry can enhance the optoelectrical properties of GBs,ultimately leading to improved device performance.展开更多
基金supported by the National Natural Science Foundation of China(No.51805265)the Fundamental Research Funds for the Central Universities,China(No.30922010921).
文摘Thin walls of an AZ91 magnesium alloy with fine equiaxed grains were fabricated via cold arc-based wire arc additive manufacturing(CA-WAAM),and the droplet transfer behaviours,microstructures,and mechanical properties were investigated.The results showed that the cold arc process reduced splashing at the moment of liquid bridge breakage and effectively shortened the droplet transfer period.The microstructures of the deposited samples exhibited layered characteristics with alternating distributions of coarse and fine grains.During layer-by-layer deposition,the β-phase precipitated and grew preferentially along grain boundaries,while the fineη-Al_(8)Mn_(5)phase was dispersed in the α-Mg matrix.The mechanical properties of the CA-WAAM deposited sample showed isotropic characteristics.The ultimate tensile strength and elongation in the building direction(BD)were 282.7 MPa and 14.2%,respectively.The microhardness values of the deposited parts were relatively uniform,with an average value of HV 69.6.
文摘Kolbroek pigs have numerous advantages as an indigenous breed including its contributions to food security. However, there are numerous concerns over the current feed regime that compromises its growth performance and carcass quality. Therefore, this study was conducted to evaluate the growth performance traits, attainment of puberty, backfat thickness (BFT), and carcass traits when boar fed diets supplemented with 10% (standard diet), 13% and 16% crude protein. Fifteen pigs per protein diets were individually housed and fed <em>ad-libitum</em> for eight weeks in a complete randomised design. Average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) were measured on a weekly basis. At the end of the trial, all boars were slaughtered and carcass quality parameters measured. Pearson’s correlation coefficients were calculated between growth performance parameters. Our data revealed that there was an increase in final body weight, ADG, ADFI accompanied by decreases in BFT and the age of attainment of puberty. There was also a positive correlation between ADFI and ADG (r = 0.78) accompanied by a low positive correlation between ADG and BFT (r = 0.12) with a high negative correlation between FCR and ADG (r = -0.94). The water holding capacity (WHC), dressing percentage and marbling mass appeared to decrease while the eye muscle area increased with protein supplementation of the diet. There were also increases in the lungs, liver, small plus large intestines and stomach with no changes in the pancreas and heart tissues. Accompanying these was observations that the meat colour lightness improved accompanied by a decline in meat redness and yellowness. In conclusion, supplementation of boar diet with increasing crude protein improved the carcass quality and growth performance of Kolbroek boars.
文摘Limited knowledge of the genetic causes of male infertility has resulted in few treatment and targeted therapeutic options. Although the ideal approach to identify infertility causing mutations is to conduct studies in the human population, this approach has progressed slowly due to the limitations described herein. Given the complexity of male fertility, the entire process cannot be modeled in vitro. As such, animal models, in particular mouse models, provide a valuable alternative for gene identification and experimentation. Since the introduction of molecular biology and recent advances in animal model production, there has been a substantial acceleration in the identification and characterization of genes associated with many diseases, including infertility. Three major types of mouse models are commonly used in biomedical research, including knockoutJknockin/gene-trapped, transgenic and chemical-induced point mutant mice. Using these mouse models, over 400 genes essential for male fertility have been revealed. It has, however, been estimated that thousands of genes are involved in the regulation of the complex process of male fertility, as many such genes remain to be characterized. The current review is by no means a comprehensive list of these mouse models, rather it contains examples of how mouse models have advanced our knowledge of post-natal germ cell development and male fertility regulation.
基金supported by the Agricultural Science and Technology Innovation Program of CAAS and China Agriculture Research System (CARS-04) awarded to T.Han of CAAS and S.E.Ibrahim of Agricultural Research Corporation(ARC)Soybean Research Program,Wad Medani,Sudan
文摘Soybean(Glycine max(L.) Merr.) is a non-native and non-staple crop in sub-Saharan Africa(SSA) with potential to be a commercial crop owing to its wide range of uses as food, feed,and industrial raw material. Soybean was first introduced to SSA by Chinese traders in the19 th century and was cultivated as an economic crop as early as 1903 in South Africa. In the past four decades, soybean cultivation area and production in SSA has increased exponentially, from about 20,000 ha and 13,000 t in the early 1970 s to 1,500,000 ha and2,300,000 t in 2016. Soybean yield has been stagnant in SSA for decades at about 1.1 t ha^(-1),much lower than the world average, representing one of the most challenging issues in the soybean industry in SSA. The low soybean yield in SSA can be attributed to the use of poorperforming varieties and to the limited application of fertilizers and rhizobial inoculants in soils with no history of soybean production. South Africa, Nigeria, Zambia, and Uganda are the leading soybean producers in SSA. Soybean research in SSA is conducted by international and national research institutions, including IITA, national soybean improvement programs, universities, and the private sector. Between 1970 and 2011, 195 soybean varieties were released by IITA, private breeders, and national soybean improvement programs in SSA. This paper reviews the history and current state of soybean production and of the utilization and adoption of tropical varieties in SSA, addresses the major soybean yield-limiting factors across the region, and discusses the potential of the soybean industry in SSA. It also highlights soybean improvement efforts and lessons learned from previous soybean improvement efforts and the current progress of some national soybean improvement programs in SSA. Opportunities for scaling up tropical soybean as a major crop across SSA countries are promising.
基金This research was conducted by the Australian Research Council Industrial Transformation Training Centre in Additive Biomanufacturing(IC160100026).The support of the Gross Foundation is also acknowledged.
文摘The additive manufacturing(AM)process plays an important role in enabling cross-disciplinary research in engineering and personalised medicine.Commercially available clinical tools currently utilised in radiotherapy are typically based on traditional manufacturing processes,often leading to non-conformal geometries,time-consuming manufacturing process and high costs.An emerging application explores the design and development of patient-specific clinical tools using AM to optimise treatment outcomes among cancer patients receiving radiation therapy.In this review,we:•highlight the key advantages of AM in radiotherapy where rapid prototyping allows for patient-specific manufacture•explore common clinical workflows involving radiotherapy tools such as bolus,compensators,anthropomorphic phantoms,immobilisers,and brachytherapy moulds;and•investigate how current AM processes are exploited by researchers to achieve patient tissuelike imaging and dose attenuations.Finally,significant AM research opportunities in this space are highlighted for their future advancements in radiotherapy for diagnostic and clinical research applications.
基金supported by the Australian Research Council(ARC)through Future Fellowship(FT210100298)Discovery Project(DP220100603)+5 种基金Linkage Project(LP210200504,LP220100088,LP230200897)Industrial Transformation Research Hub(IH240100009)schemesthe China Postdoctoral Science Foundation(2023M743430)the Australian Government through the Cooperative Research Centres Projects(CRCPXIII000077)the Australian Renewable Energy Agency(ARENA)as part of ARENA’s Transformative Research Accelerating Commercialisation Program(TM021)European Commission's Australia-Spain Network for Innovation and Research Excellence(AuSpire).
文摘Electrochemical CO_(2) reduction reaction(CO_(2)RR)is a promising process for reducing CO_(2) emissions and producing high-value chemicals.However,this process remains hindered by diffusion-limited mass transfer,low activity,and high overpotentials.Here,we controllably prepared hierarchically porous nitrogen-doped carbon,carbon nanosheets,and carbon nanotubes confined single-atom Fe catalysts for electrochemical CO_(2) reduction.The hierarchically porous Fe-N-C(Fe-HP)exhibited prominent performance with a Faradaic efficiency of CO(FECO)up to 80% and a CO partial current density(jCO)of -5.2 mA·cm^(-2) at -0.5 V vs.reversible hydrogen electrode(RHE),far outperforming the single-atom Fe on N-C nanosheets(Fe-NS)and N-C nanotubes(Fe-NT).The detailed characterizations and kinetic analysis revealed that the hierarchically porous structure accelerated the mass transfer and electron transfer processes toward single-atom Fe sites,promoting the desorption of CO and thereby enhancing CO_(2) reduction efficiency.This study provides a promising approach to designing efficient single-atom catalysts with porous structures for energy conversion applications.
基金the National Natural Science Foundation of China(Grants 12204272,52073162,52272157)Taishan Scholars Program(Grant tstp20230610)+2 种基金Shandong Provincial Natural Science Foundation(Grants ZR2022YQ04,ZR2021QF016)State Key Laboratory of Crystal Materials(Grant KF2209)the Hubei Longzhong Laboratory(Grant 2022KF-01)for financial support.
文摘Broad-spectrum photodetectors(PDs)are essential for various health monitoring,night vision,and telecommunications applications,but their detectivity in a wide absorbance region is limited by undesirable electronic response properties.Colloidal quantum dots(CQDs)are a promising system for broad-spectrum detection,whereas their practical potential is hindered by suboptimal dark current characteristics.To overcome these challenges,we propose a layered architecture comprising CQDs and a bulk heterojunction(BHJ)organic film as a hole transport layer.The integration of PbS CQDs offers multiple benefits,including bandgap tuning for minimizing thermal carriers,surface passivation to reduce recombination rates,and the formation of high-quality interfaces with organic layers,which collectively contribute to suppressing dark current leakage and thermal excitations by suppressing stray electrons.By integrating ITIC into the BHJ film,the device detectability is significantly enhanced,reaching 1013 Jones in the 400–1000 nm spectral range.This improvement is attributed to the higher lowest unoccupied molecular orbital(LUMO)of ITIC molecules,which effectively hinders electron injection.Additionally,J-aggregation-induced molecular stacking and optimized phase separation of BHJ films contribute to the enhanced performance.The integration of diverse materials offers greater flexibility in device design and functionality,enabling the development of more advanced and sophisticated optoelectronic devices.Furthermore,this approach could significantly enhance the theoretical and practical understanding of optoelectronic device engineering,leading to the development of more advanced optoelectronic devices.
文摘The CTB Water Wall project is a maximal product life cycle utilization concept study by members of the space architecture design community.Its function is to demonstrate a human space activity Cargo Transport Bag(CTB)that becomes a primary water recycling membrane element after delivery of cargo,and then a permanent architectural building block for sustainable space habitation after its use in water treatment is complete.As such,it is intended as an experiment in radical life cycle product optimization in an extremely mass-constrained application environment(human space operations).It also introduces some fundamentally interesting concepts in architectural use of waste materials in extreme environments.Finally,it is in some ways a simple,tactile and visual demonstration of how far sustainable product design can be taken,if the motivation and technical justification are present.
文摘为改善高氮钢(high-nitrogen steel,HNS)电弧增材过程中出现的力学性能降低、氮逸出等问题,在超音频脉冲熔化极气体保护(ultrasonic frequency pulsed gas metal arc,UFP-GMA)及脉冲熔化极气体保护(pulse gas metal arc,P-GMA)工艺下进行高氮钢增材试验,分析超音频脉冲电流对高氮钢增材显微组织及力学性能的影响.研究结果表明,两种工艺方法下高氮钢增材件组织均为树枝晶铁素体及奥氏体基体组成,由于散热方向及温度梯度变化使铁素体组织由长树枝晶变为短树枝晶,生长方向也呈现多向性,叠加超音频脉冲电流后能产生高频振动效应,破碎枝晶,细化晶粒,使界面处树枝晶变为等轴晶;相比于常规脉冲GMA增材工艺,叠加超音频脉冲电流之后力学性能均有所提高,搭接方向抗拉强度为987.1 MPa,提高了7.1%,增材方向抗拉强度为970.6 MPa,提高了6.2%,显微硬度为350.3 HV,两种工艺下断裂模式都呈典型的韧性断裂特征,在韧窝中有第二相析出,为Cr-Mn-Fe氧化物,使Mn元素析出,力学性能下降.
基金supported by the Australian Research Council(Grant No.CE230100012)。
文摘The onset,cessation,and length of the rainy season are crucial for global water resources,agricultural practices,and food security.However,the response of precipitation seasonality to global warming remains uncertain.In this study,we analyze how global warming levels(GWLs)of 1.5℃ and 2℃ could affect the timing of rainfall onset(RODs),rainfall cessation(RCDs),and the overall duration of the rainy season(LRS)over global land monsoon(GLM)regions using simulations from CMIP6 under the SSP2-4.5 and SSP5-8.5 scenarios.With high model consensus,our results reveal that RODs are projected to occur later over Southern Africa,North Africa,and South America,but earlier over South Asia and Australia,in a warmer climate.The projected early RODs in Australia are more pronounced at the 2℃ GWL under SSP5-8.5.On the other hand,early RCDs are projected over South America and East Asia,while late RCDs are projected over North Africa,with high inter-model agreement.These changes are associated with a future decrease in LRS in most GLM regions.Additionally,we found that continuous warming over 1.5℃ will further reduce the length of the rainy season,especially over the South America,North Africa,and Southern Africa monsoon regions.The findings underscore the urgent need to mitigate global warming.
基金financial support provided by the Natural Science Foundation of Hebei Province,China(No.E2024105036)the Tangshan Talent Funding Project,China(Nos.B202302007 and A2021110015)+1 种基金the National Natural Science Foundation of China(No.52264042)the Australian Research Council(No.IH230100010)。
文摘Automated classification of gas flow states in blast furnaces using top-camera imagery typically demands a large volume of labeled data,whose manual annotation is both labor-intensive and cost-prohibitive.To mitigate this challenge,we present an enhanced semi-supervised learning approach based on the Mean Teacher framework,incorporating a novel feature loss module to maximize classification performance with limited labeled samples.The model studies show that the proposed model surpasses both the baseline Mean Teacher model and fully supervised method in accuracy.Specifically,for datasets with 20%,30%,and 40%label ratios,using a single training iteration,the model yields accuracies of 78.61%,82.21%,and 85.2%,respectively,while multiple-cycle training iterations achieves 82.09%,81.97%,and 81.59%,respectively.Furthermore,scenario-specific training schemes are introduced to support diverse deployment need.These findings highlight the potential of the proposed technique in minimizing labeling requirements and advancing intelligent blast furnace diagnostics.
基金This research was funded by the CSIRO ResearchPlus Science Leader Grant Program.
文摘Ore sorting is a preconcentration technology and can dramatically reduce energy and water usage to improve the sustainability and profitability of a mining operation.In porphyry Cu deposits,Cu is the primary target,with ores usually containing secondary‘pay’metals such as Au,Mo and gangue elements such as Fe and As.Due to sensing technology limitations,secondary and deleterious materials vary in correlation type and strength with Cu but cannot be detected simultaneously via magnetic resonance(MR)ore sorting.Inferring the relationships between Cu and other elemental abundances is particularly critical for mineral processing.The variations in metal grade relationships occur due to the transition into different geological domains.This raises two questions-how to define these geological domains and how the metal grade relationship is influenced by these geological domains.In this paper,linear relationship is assumed between Cu grade and other metal grades.We applies a Bayesian hierarchical(partial-pooling)model to quantify the linear relationships between Cu,Au,and Fe grades from geochemical bore core data.The hierarchical model was compared with two other models-‘complete-pooling’model and‘nopooling’model.Mining blocks were split based on spatial domain to construct hierarchical model.Geochemical bore core data records metal grades measured from laboratory assay with spatial coordinates of sample location.Two case studies from different porphyry Cu deposits were used to evaluate the performance of the hierarchical model.Markov chain Monte Carlo(MCMC)was used to sample the posterior parameters.Our results show that the Bayesian hierarchical model dramatically reduced the posterior predictive variance for metal grades regression compared to the no-pooling model.In addition,the posterior inference in the hierarchical model is insensitive to the choice of prior.The data is wellrepresented in the posterior which indicates a robust model.The results show that the spatial domain can be successfully utilised for metal grade regression.Uncertainty in estimating the relationship between pay metals and both secondary and gangue elements is quantified and shown to be reduced with partial-pooling.Thus,the proposed Bayesian hierarchical model can offer a reliable and stable way to monitor the relationship between metal grades for ore sorting and other mineral processing options.
基金financially supported by ARC Linkage project(LP210200642)ARC Center of Excellence for Quantum Biotechnology(grant no.CE230100021)+1 种基金National Health and Medical Research Council Investigator Fellowship—(grant no.APP2017499)Chan Zuckerberg Initiative Deep Tissue Imaging Phase 2(grant no.DT12-0000000182).
文摘Lateral flow immunoassays(LFIAs)are low-cost,rapid,and easy to use for pointof-care testing(POCT),but the majority of the available LFIA tests are indicative,rather than quantitative,and their sensitivity in antigen tests are usually limited at the nanogram range,which is primarily due to the passive capillary fluidics through nitrocellulose membranes,often associated with non-specific bindings and high background noise.To overcome this challenge,we report a Beads-on-a-Tip design by replacing nitrocellulose membranes with a pipette tip loaded with magnetic beads.The beads are pre-conjugated with capture antibodies that support a typical sandwich immunoassay.This design enriches the low-abundant antigen proteins and allows an active washing process to significantly reduce non-specific bindings.To further improve the detection sensitivity,we employed upconversion nanoparticles(UCNPs)as luminescent reporters and SARS-CoV-2 spike(S)antigen as a model analyte to benchmark the performance of this design against our previously reported methods.We found that the key to enhance the immunocomplex formation and signal-to-noise ratio lay in optimizing incubation time and the UCNP-to-bead ratio.We therefore successfully demonstrated that the new method can achieve a very large dynamic range from 500 fg/mL to 10μg/mL,across over 7 digits,and a limit of detection of 706 fg/mL,nearly another order of magnitude lower than the best reported LFIA using UCNPs in COVID-19 spike antigen detection.Our system offers a promising solution for ultra-sensitive and quantitative POCT diagnostics.
基金support from the Key Research and Development Program of Shandong Province(No.2022SFGC0501)Shenzhen Science and Technology Program(International Cooperation Research)(No.GJHZ20240218113407015)+9 种基金Shenzhen Fundamental Research Program(Natural Science Foundation)(No.JCYJ20240813175900001)support from the Australian Research Council through the Discovery Project scheme(Grant No.DP190103186,DP220100603)support through the Future Fellowship scheme(Grant No.FT210100806)Discovery Project scheme(Grant No.DP250100980)Linkage Project scheme(LP210200345)the Industrial Transformation Research Hubs(Grant No.IH240100009)support through the Future Fellowship scheme(Grant No.FT220100559)Linkage Projects(Grant No.LP210100467)support through the Discovery Early Career Researcher Award scheme(DE230100383)support from the Natural Science Foundation of Shandong Province(Grant No.ZR2021ME162).
文摘Governed by the second law of thermodynamics,waste heat generation is inevitable and has been a major source of energy loss and environmental concern in human society.Harvesting waste heat into useful energy has thus become a paramount priority,but has remained challenging with efficiency and cost constraints.Thermoelectric generators(TEGs),which convert heat into electricity whenever there is a temperature difference,play a crucial role in waste heat harvesting.However,sustaining the temperature difference for uninterrupted and high-power density electricity generation is a major challenge in TEGs to achieve practical applications due to the thermal equilibrium.Here,we demonstrate a diurnal waste heat harvester by integrating a high-power radiative cooling film as the cool end of TEGs to enable a large and continuous temperature difference.Significant voltage increase from 30.0 mV to 65.7 mV was achieved,leading to a dramatic power density enhancement of 4.8 times from 35.2 mW m^(-2)to 168.6 mW m^(-2).In an open zone,an ultra-high power density of 2.76 W m^(-2)was achieved at a heat source temperature of 80°C,exceeding the performance of state-of-the-art radiatively cooled TEGs.More importantly,a portable and foldable thermal energy harvesting prototype composed of 24 TEGs arranged in an array has been constructed.When attached to a hot object(e.g.a car engine hood),it can output 5 V to charge personal electronics(e.g.a cellphone),making it a promising practical device for harvesting waste heat in a wide range of outdoor applications.
文摘The Lachlan Orogen of New South Wales,Victoria and eastern Tasmania is the best understood element of the eastern Australian Tasmanides.The Tasmanides encompass continental growth in a Neoproterozoic passive margin setting and a Paleozoic–Mesozoic active margin in east Gondwana,bounded to the east by the Pacific Ocean.In the Ordovician,the supra-subduction zone element in the Lachlan Orogen is the Macquarie Arc.This comprises one minor and three major belts of mafic to intermediate volcanic and volcaniclastic rocks,limestones and intrusions that,with two hiatuses in magmatism,span the Ordovician and extend into the Early Silurian.The three major belts in central New South Wales are separated by Silurian–Devonian rift basins and are therefore,inferred to have been rifted apart during crustal extension.Chemical and isotopic data suggest the Macquarie Arc is intraoceanic,developed on primitive oceanic crust.Despite this,key features such as its longevity,stacked magmatic phases,little deformation and flanking coeval craton-derived turbidites and black shales with no provenance mixing indicate differences from modern intraoceanic arcs.Paleogeographic setting and magmatic evolution of the Macquarie Arc provided perfect conditions for mainly porphyry-related,rich Au-Cu deposits,in the Ordovician,and especially in the Early Silurian after amalgamation of the arc with its flanking terranes.
基金support from the Australian Research Council through Discovery Grants and the ARC Centre of Excellence in Future Low-Energy Electronics Technologies(FLEET)supported by the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(NRF-2021K1A4A7A03093851)+1 种基金J.S.Y.acknowledges the Royal Society research grant(RGS/R1/221369)the support by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MEST)(RS-2023-00257494 and 2022H1D3A2A01082324).
文摘Mixed halide perovskites exhibit great potential as materials for the future generation of photovoltaic devices.Yet,their reaction to moisture remains uncertain,necessitating further exploration.While prolonged exposure to moisture can lead to degradation,it can also passivate traps at an optimal moisture level.Here,we use scanning probe microscopy to perform nanoscale moisture-dependent photovoltaic characterizations of open and compressed grain boundary(GB)structures of wide bandgap(FAPbI_(3))_(0.3)(FAPbBr_(3))_(0.7) perovskites.The investigation reveals a decrease in the potential barrier at compact GBs with increasing moisture levels,contrasting with the behavior observed in open GBs.Moreover,the photocurrent distribution over both samples proportionally increases when relative humidity(RH)is raised from 10%to 60%.Notably,following a 24-h exposure at RH 60%,the compact-GB sample demonstrates:i)a reduction in the density of charged trap states at GBs,ii)higher photocurrent,accompanied by a noticeable decrease in current hysteresis compared to the open GB sample,and iii)further enhancement in device efficiency and crystallinity compared to devices with open GBs.These findings suggest that optimizing humidity conditions in engineering the GB chemistry can enhance the optoelectrical properties of GBs,ultimately leading to improved device performance.
