Conjugated polymers(CPs)have emerged as an interesting class of materials in modern electronics and photonics,characterized by their unique delocalizedπ-electron systems that confer high flexibility,tunable electroni...Conjugated polymers(CPs)have emerged as an interesting class of materials in modern electronics and photonics,characterized by their unique delocalizedπ-electron systems that confer high flexibility,tunable electronic properties,and solution processability.These organic polymers present a compelling alternative to traditional inorganic semiconductors,offering the potential for a new generation of optoelectronic devices.This review explores the evolving role of CPs,exploring the molecular design strategies and innovative approaches that enhance their optoelectronic properties.We highlight notable progress toward developing faster,more efficient,and environmentally friendly devices by analyzing recent advancements in CP-based devices,including organic photovoltaics,field-effect transistors,and nonvolatile memories.The integration of CPs in flexible sustainable technologies underscores their potential to revolutionize future electronic and photonic systems.As ongoing research pushes the frontiers of molecular engineering and device architecture,CPs are poised to play an essential role in shaping next-generation technologies that prioritize performance,sustainability,and adaptability.展开更多
Dermatophyte infection or ringworm is a superficial cutaneous infection with one or more of the fungal species of the keratinophilic genera Microsporum, Trichophyton, or Epidermophyton and is a zoonosis with a great i...Dermatophyte infection or ringworm is a superficial cutaneous infection with one or more of the fungal species of the keratinophilic genera Microsporum, Trichophyton, or Epidermophyton and is a zoonosis with a great impact on public health. Dermatophytes were identified from rabbit sample cultures submitted to mycological examination in the Laboratory of Microbiology of the University of Tr^-os-Montes e Alto Douro, Vila Real, Portugal. All samples were collected from suspected clinical cases. Dermatophytes were cultured from 4 of the 55 specimens （7.3%）. The dermatophytes isolated were Trichophyton mentagrophytes var. mentagrophytes （1.8%） and Microsporum gypseum （5.5%）. Microscopic examination was negative in all specimens. In this work, Scopulariopsis spp., a contaminant mould, was identified in 13 specimens （23.6%）. The proportion of positive samples in relation to the number of samples examined from cases suspected was very low. As all samples were collected from rabbits with compatible signs, we presume that the low prevalence of isolation was due to laboratory constraints on dermatophytes diagnosis.展开更多
AIM: To study the therapeutic effect of three tubeguides with electrical conductivity associated to mesenchymal stem cells(MSCs) on neuro-muscular regeneration after neurotmesis.METHODS: Rats with 10-mm gap nerve inju...AIM: To study the therapeutic effect of three tubeguides with electrical conductivity associated to mesenchymal stem cells(MSCs) on neuro-muscular regeneration after neurotmesis.METHODS: Rats with 10-mm gap nerve injury were tested using polyvinyl alcohol(PVA), PVA-carbon nanotubes(CNTs) and MSCs, and PVA-polypyrrole(PPy). The regenerated nerves and tibialis anterior muscles were processed for stereological studies after 20 wk. The functional recovery was assessed serially for gait biomechanical analysis, by extensor postural thrust, sciatic functional index and static sciatic functionalindex(SSI), and by withdrawal reflex latency(WRL). In vitro studies included cytocompatibility, flow cytometry, reverse transcriptase polymerase chain reaction and karyotype analysis of the MSCs. Histopathology of lung, liver, kidneys, and regional lymph nodes ensured the biomaterials biocompatibility. RESULTS: SSI remained negative throughout and independently from treatment. Differences between treted groups in the severity of changes in WRL existed, showing a faster regeneration for PVA-CNTs-MSCs(P < 0.05). At toe-off, less acute ankle joint angles were seen for PVA-CNTs-MSCs group(P = 0.051) suggesting improved ankle muscles function during the push off phase of the gait cycle. In PVA-PPy and PVA-CNTs groups, there was a 25% and 42% increase of average fiber area and a 13% and 21% increase of the "minimal Feret's diameter" respectively. Stereological analysis disclosed a significantly(P < 0.05) increased myelin thickness(M), ratio myelin thickness/axon diameter(M/d) and ratio axon diameter/fiber diameter(d/D; g-ratio) in PVA-CNT-MSCs group(P < 0.05). CONCLUSION: Results revealed that treatment with MSCs and PVA-CNTs tube-guides induced better nerve fiber regeneration. Functional and kinematics analysis revealed positive synergistic effects brought by MSCs and PVA-CNTs. The PVA-CNTs and PVA-PPy are promising scaffolds with electric conductive properties, bio- and cytocompatible that might prevent the secondary neurogenic muscular atrophy by improving the reestablishment of the neuro-muscular junction.展开更多
A significant number of stallions produce low quality ejaculates with high sensibility to chilling. Single Layer Centrifugation (SLC) with Andro-coll-ETM has been presented as an efficient method of selecting good qua...A significant number of stallions produce low quality ejaculates with high sensibility to chilling. Single Layer Centrifugation (SLC) with Andro-coll-ETM has been presented as an efficient method of selecting good quality spermatozoa. In the current study, changes in sperm quality (motility, viability, acrosome integrity and DNA damage) occurring during storage at 5?C for a maximum of 72 h, were investigated. For that, one ejaculate from 12 stallions was split in two aliquots: control and SLC-selected. Both aliquots were chilled and stored at 5?C and spermatozoa were evaluated for motility, viability and acrosome integrity at 24, 48 and 72 h post collection. DNA damage was evaluated at 48 h post collection using the comet assay. In the SLC-selected aliquots, there was a significant improvement in terms of progressive motility (0 h: P = 0.005;24 h: P 0.05). SLC with Androcoll-ETM improved semen quality prolonging sperm longevity of chilled semen (P = 0.012). This positive effect was more evident in ejaculates most sensitive to chilling that had a sharp decrease in motility in the first 24 h of refrigeration and for all ejaculates at 72 h post-chilling. Therefore, this method reveals to be a useful technique for selecting spermatozoa and maintain sperm quality during storage.展开更多
Enhanced oil recovery(EOR)technologies are used to recover most of the trapped crude oil from our limited reserves.With the escalating energy demand,EOR will achieve substantial economic benefits and greatly help in t...Enhanced oil recovery(EOR)technologies are used to recover most of the trapped crude oil from our limited reserves.With the escalating energy demand,EOR will achieve substantial economic benefits and greatly help in the exploitation of natural oil reserves.Recent research focused on microfluidic platforms for studying flow behavior during EOR flooding.These platforms are micro-sized,and allow processing and visualization of a minimal amount of fluid,making them an intriguing tool for studying the microscale phenomena in EOR processes.This review presents a comprehensive and concise literature on microfluidic trends and developments in EOR.A particular focus is on the use of these platforms to assess oil recovery via chemical-based flooding methods,to understand the associated emulsification mechanisms,and to mimic subsurface morphology and mineralogy of reservoirs.Furthermore,an outlook on the advancement of microfluidics utilization in EOR applications is discussed,covering development efficient micro-scale separators,3D printing,and Artificial Intelligence applications.Microfluidic platforms provide valuable insights into EOR processes,and ongoing advancements in microfluidics hold the potential to enhance oil recovery efficiency and optimize EOR techniques.展开更多
Understanding the hydrogenation routes in the electrochemical CO_((2))reduction reaction(eCO_((2))RR)is essential for the selective production of oxygenated and hydrocarbon products.Hydrogenation dictates the selectiv...Understanding the hydrogenation routes in the electrochemical CO_((2))reduction reaction(eCO_((2))RR)is essential for the selective production of oxygenated and hydrocarbon products.Hydrogenation dictates the selectivity by determining whether hydrogen preferentially attacks oxygen or carbon in one intermediate.Oxygenated products are particularly valuable due to their higher energy density and economic potential,making enhancing their Faradaic efficiency(FE)vital.However,the factors determining hydrogenation selectivity remain unclear,making precise control over product distribution challenging.Herein,we systematically investigate hydrogenation mechanisms from CO to CH4,C_(2)H_(5)OH,and C_(2)H4using density functional theory(DFT)calculations with an explicit solvation model.Our results reveal that surface hydrogen preferentially attacks carbon atoms via the Langmuir-Hinshelwood(LH)mechanism,while solvent hydrogen attacks oxygen atoms via the Eley-Rideal(ER)mechanism.This insight suggests that enhancing the LH mechanism could promote oxy-generating products when the solvent environment is determined.Microkinetic modeling supports these findings by adjusting the LH mechanism through H_(2)partial pressure modulation.Further experiments demonstrate FE change of ethanol,ethylene,and methane under different CO:H_(2)/N_(2)partial pressures at different currents.Experiment results confirm that increasing the coverage of*H can effectively enhance the FE of oxygenated compounds while also causing rapid saturation of carbon atoms,thereby suppressing C-C coupling and reducing the FE of multi-carbon products.These computational and experimental findings provide a mechanistic foundation for optimizing eCO_((2))RR selectivity through hydrogen coverage modulation.展开更多
Anti-perovskites A3SnO(A=Ca,Sr,and Ba)are an important class of materials due to the emergence of Dirac cones and tiny mass gaps in their band structures originating from an intricate interplay of crystal symmetry,spi...Anti-perovskites A3SnO(A=Ca,Sr,and Ba)are an important class of materials due to the emergence of Dirac cones and tiny mass gaps in their band structures originating from an intricate interplay of crystal symmetry,spin–orbit coupling,and band overlap.This provides an exciting playground for modulating their electronic properties in the two-dimensional(2D)limit.Herein,we employ first-principles density functional theory(DFT)calculations by combining dispersion-corrected SCAN+rVV10 and mBJ functionals for a comprehensive side-by-side comparison of the structural,thermodynamic,dynamical,mechanical,electronic,and thermoelectric properties of bulk and monolayer(one unit cell thick)A3SnO anti-perovskites.Our results show that 2D monolayers derived from bulk A3SnO anti-perovskites are structurally and energetically stable.Moreover,Rashba-type splitting in the electronic structure of Ca3SnO and Sr3SnO monolayers is observed owing to strong spin–orbit coupling and inversion asymmetry.On the other hand,monolayer Ba3SnO exhibits Dirac cone at the high-symmetryΓpoint due to the domination of band overlap.Based on the predicted electronic transport properties,it is shown that inversion asymmetry plays an essential character such that the monolayers Ca3SnO and Sr3SnO outperform thermoelectric performance of their bulk counterparts.展开更多
The key to high performance for GPU architecture lies in its massive threading capability to drive a large number of cores and enable execution overlapping among threads. However, in reality, the number of threads tha...The key to high performance for GPU architecture lies in its massive threading capability to drive a large number of cores and enable execution overlapping among threads. However, in reality, the number of threads that can simultaneously execute is often limited by the size of the register file on GPUs. The traditional SRAM-based register file takes up so large amount of chip area that it cannot scale to meet the increasing demand of GPU applications. Racetrack memory （RM） is a promising technology for designing large capacity register file on GPUs due to its high data storage density. However, without careful deployment of RM-based register file, the lengthy shift operations of RM may hurt the performance. In this paper, we explore RM for designing high-performance register file for GPU architecture. High storage density RM helps to improve the thread level parallelism （TLP）, but if the bits of the registers are not aligned to the ports, shift operations are required to move the bits to the access ports before they are accessed, and thus the read/write operations are delayed. We develop an optimization framework for RM-based register file on GPUs, which employs three different optimization techniques at the application, compilation, and architecture level, respectively. More clearly, we optimize the TLP at the application level, design a register mapping algorithm at the compilation level, and design a preshifting mechanism at the architecture level. Collectively, these optimizations help to determine the TLP without causing cache and register file resource contention and reduce the shift operation overhead. Experimental results using a variety of representative workloads demonstrate that our optimization framework achieves up to 29% （21% on average） performance improvement.展开更多
基金Khalifa University,Abu Dhabi,for the generous support of this researchthe financial support from the Khalifa University Research&Innovation Grant(RIG-2023-005)。
文摘Conjugated polymers(CPs)have emerged as an interesting class of materials in modern electronics and photonics,characterized by their unique delocalizedπ-electron systems that confer high flexibility,tunable electronic properties,and solution processability.These organic polymers present a compelling alternative to traditional inorganic semiconductors,offering the potential for a new generation of optoelectronic devices.This review explores the evolving role of CPs,exploring the molecular design strategies and innovative approaches that enhance their optoelectronic properties.We highlight notable progress toward developing faster,more efficient,and environmentally friendly devices by analyzing recent advancements in CP-based devices,including organic photovoltaics,field-effect transistors,and nonvolatile memories.The integration of CPs in flexible sustainable technologies underscores their potential to revolutionize future electronic and photonic systems.As ongoing research pushes the frontiers of molecular engineering and device architecture,CPs are poised to play an essential role in shaping next-generation technologies that prioritize performance,sustainability,and adaptability.
文摘Dermatophyte infection or ringworm is a superficial cutaneous infection with one or more of the fungal species of the keratinophilic genera Microsporum, Trichophyton, or Epidermophyton and is a zoonosis with a great impact on public health. Dermatophytes were identified from rabbit sample cultures submitted to mycological examination in the Laboratory of Microbiology of the University of Tr^-os-Montes e Alto Douro, Vila Real, Portugal. All samples were collected from suspected clinical cases. Dermatophytes were cultured from 4 of the 55 specimens （7.3%）. The dermatophytes isolated were Trichophyton mentagrophytes var. mentagrophytes （1.8%） and Microsporum gypseum （5.5%）. Microscopic examination was negative in all specimens. In this work, Scopulariopsis spp., a contaminant mould, was identified in 13 specimens （23.6%）. The proportion of positive samples in relation to the number of samples examined from cases suspected was very low. As all samples were collected from rabbits with compatible signs, we presume that the low prevalence of isolation was due to laboratory constraints on dermatophytes diagnosis.
基金Supported by System of Incentives for Research and Technological development of QREN in the scope of project n°38853/2013-DEXGELERATION:"Solucoes avancadas de regeneracao ossea com base em hidrogeis de dextrin"the European Community FEDER fund through ON2-O Novo Norte-North Portugal Regional Operational Program 2007-2013+4 种基金Project n°34128-BEPIM II:"Microdispositivos biomédicos com capacidade osteointegrativa porμPIM"funded by Ad Ithe program COMPETE-Programa Operacional Factores de Competitividade,projects Pest-OE/AGR/UI0211/2011PTDC/CVT/103081/2008CDRsp’s Strategic Project-UI-4044-2011-2012(Pest-OE/EME/UI4044/2011)funding from FCT
文摘AIM: To study the therapeutic effect of three tubeguides with electrical conductivity associated to mesenchymal stem cells(MSCs) on neuro-muscular regeneration after neurotmesis.METHODS: Rats with 10-mm gap nerve injury were tested using polyvinyl alcohol(PVA), PVA-carbon nanotubes(CNTs) and MSCs, and PVA-polypyrrole(PPy). The regenerated nerves and tibialis anterior muscles were processed for stereological studies after 20 wk. The functional recovery was assessed serially for gait biomechanical analysis, by extensor postural thrust, sciatic functional index and static sciatic functionalindex(SSI), and by withdrawal reflex latency(WRL). In vitro studies included cytocompatibility, flow cytometry, reverse transcriptase polymerase chain reaction and karyotype analysis of the MSCs. Histopathology of lung, liver, kidneys, and regional lymph nodes ensured the biomaterials biocompatibility. RESULTS: SSI remained negative throughout and independently from treatment. Differences between treted groups in the severity of changes in WRL existed, showing a faster regeneration for PVA-CNTs-MSCs(P < 0.05). At toe-off, less acute ankle joint angles were seen for PVA-CNTs-MSCs group(P = 0.051) suggesting improved ankle muscles function during the push off phase of the gait cycle. In PVA-PPy and PVA-CNTs groups, there was a 25% and 42% increase of average fiber area and a 13% and 21% increase of the "minimal Feret's diameter" respectively. Stereological analysis disclosed a significantly(P < 0.05) increased myelin thickness(M), ratio myelin thickness/axon diameter(M/d) and ratio axon diameter/fiber diameter(d/D; g-ratio) in PVA-CNT-MSCs group(P < 0.05). CONCLUSION: Results revealed that treatment with MSCs and PVA-CNTs tube-guides induced better nerve fiber regeneration. Functional and kinematics analysis revealed positive synergistic effects brought by MSCs and PVA-CNTs. The PVA-CNTs and PVA-PPy are promising scaffolds with electric conductive properties, bio- and cytocompatible that might prevent the secondary neurogenic muscular atrophy by improving the reestablishment of the neuro-muscular junction.
基金partially financed by Projects PTDC/CVT/108456/2008(FCT)and COMPETE:FCOMP-01-0124-FEDER-009565(FEDER),“Development of methods to increase the fertilizing ability of chilled and frozen stallion semen:a multidisciplinary ap-proach”.
文摘A significant number of stallions produce low quality ejaculates with high sensibility to chilling. Single Layer Centrifugation (SLC) with Andro-coll-ETM has been presented as an efficient method of selecting good quality spermatozoa. In the current study, changes in sperm quality (motility, viability, acrosome integrity and DNA damage) occurring during storage at 5?C for a maximum of 72 h, were investigated. For that, one ejaculate from 12 stallions was split in two aliquots: control and SLC-selected. Both aliquots were chilled and stored at 5?C and spermatozoa were evaluated for motility, viability and acrosome integrity at 24, 48 and 72 h post collection. DNA damage was evaluated at 48 h post collection using the comet assay. In the SLC-selected aliquots, there was a significant improvement in terms of progressive motility (0 h: P = 0.005;24 h: P 0.05). SLC with Androcoll-ETM improved semen quality prolonging sperm longevity of chilled semen (P = 0.012). This positive effect was more evident in ejaculates most sensitive to chilling that had a sharp decrease in motility in the first 24 h of refrigeration and for all ejaculates at 72 h post-chilling. Therefore, this method reveals to be a useful technique for selecting spermatozoa and maintain sperm quality during storage.
基金supported by Khalifa University of Science and Technology under Awards No.[CIRA-2020-34]Center of Catalysis and Separation (CeCaS) Theme Ⅱ-under Awards No.[RC2-2018-024]。
文摘Enhanced oil recovery(EOR)technologies are used to recover most of the trapped crude oil from our limited reserves.With the escalating energy demand,EOR will achieve substantial economic benefits and greatly help in the exploitation of natural oil reserves.Recent research focused on microfluidic platforms for studying flow behavior during EOR flooding.These platforms are micro-sized,and allow processing and visualization of a minimal amount of fluid,making them an intriguing tool for studying the microscale phenomena in EOR processes.This review presents a comprehensive and concise literature on microfluidic trends and developments in EOR.A particular focus is on the use of these platforms to assess oil recovery via chemical-based flooding methods,to understand the associated emulsification mechanisms,and to mimic subsurface morphology and mineralogy of reservoirs.Furthermore,an outlook on the advancement of microfluidics utilization in EOR applications is discussed,covering development efficient micro-scale separators,3D printing,and Artificial Intelligence applications.Microfluidic platforms provide valuable insights into EOR processes,and ongoing advancements in microfluidics hold the potential to enhance oil recovery efficiency and optimize EOR techniques.
基金supported by the Marsden Fund Council from Government Funding(21-UOA-237)the Catalyst:Seeding General(24-UOA-048-CSG)financial support for this work from Khalifa University(FSU-2025-006)。
文摘Understanding the hydrogenation routes in the electrochemical CO_((2))reduction reaction(eCO_((2))RR)is essential for the selective production of oxygenated and hydrocarbon products.Hydrogenation dictates the selectivity by determining whether hydrogen preferentially attacks oxygen or carbon in one intermediate.Oxygenated products are particularly valuable due to their higher energy density and economic potential,making enhancing their Faradaic efficiency(FE)vital.However,the factors determining hydrogenation selectivity remain unclear,making precise control over product distribution challenging.Herein,we systematically investigate hydrogenation mechanisms from CO to CH4,C_(2)H_(5)OH,and C_(2)H4using density functional theory(DFT)calculations with an explicit solvation model.Our results reveal that surface hydrogen preferentially attacks carbon atoms via the Langmuir-Hinshelwood(LH)mechanism,while solvent hydrogen attacks oxygen atoms via the Eley-Rideal(ER)mechanism.This insight suggests that enhancing the LH mechanism could promote oxy-generating products when the solvent environment is determined.Microkinetic modeling supports these findings by adjusting the LH mechanism through H_(2)partial pressure modulation.Further experiments demonstrate FE change of ethanol,ethylene,and methane under different CO:H_(2)/N_(2)partial pressures at different currents.Experiment results confirm that increasing the coverage of*H can effectively enhance the FE of oxygenated compounds while also causing rapid saturation of carbon atoms,thereby suppressing C-C coupling and reducing the FE of multi-carbon products.These computational and experimental findings provide a mechanistic foundation for optimizing eCO_((2))RR selectivity through hydrogen coverage modulation.
基金The computations were enabled by resources provided by the Swedish National Infrastructure for Computing(SNIC)at HPC2N and NSC partially funded by the Swedish Research Council through grant agreement no.2018-05973.
文摘Anti-perovskites A3SnO(A=Ca,Sr,and Ba)are an important class of materials due to the emergence of Dirac cones and tiny mass gaps in their band structures originating from an intricate interplay of crystal symmetry,spin–orbit coupling,and band overlap.This provides an exciting playground for modulating their electronic properties in the two-dimensional(2D)limit.Herein,we employ first-principles density functional theory(DFT)calculations by combining dispersion-corrected SCAN+rVV10 and mBJ functionals for a comprehensive side-by-side comparison of the structural,thermodynamic,dynamical,mechanical,electronic,and thermoelectric properties of bulk and monolayer(one unit cell thick)A3SnO anti-perovskites.Our results show that 2D monolayers derived from bulk A3SnO anti-perovskites are structurally and energetically stable.Moreover,Rashba-type splitting in the electronic structure of Ca3SnO and Sr3SnO monolayers is observed owing to strong spin–orbit coupling and inversion asymmetry.On the other hand,monolayer Ba3SnO exhibits Dirac cone at the high-symmetryΓpoint due to the domination of band overlap.Based on the predicted electronic transport properties,it is shown that inversion asymmetry plays an essential character such that the monolayers Ca3SnO and Sr3SnO outperform thermoelectric performance of their bulk counterparts.
基金This work was supported by the National Natural Science Foundation of China under Grant No. 61300005.
文摘The key to high performance for GPU architecture lies in its massive threading capability to drive a large number of cores and enable execution overlapping among threads. However, in reality, the number of threads that can simultaneously execute is often limited by the size of the register file on GPUs. The traditional SRAM-based register file takes up so large amount of chip area that it cannot scale to meet the increasing demand of GPU applications. Racetrack memory （RM） is a promising technology for designing large capacity register file on GPUs due to its high data storage density. However, without careful deployment of RM-based register file, the lengthy shift operations of RM may hurt the performance. In this paper, we explore RM for designing high-performance register file for GPU architecture. High storage density RM helps to improve the thread level parallelism （TLP）, but if the bits of the registers are not aligned to the ports, shift operations are required to move the bits to the access ports before they are accessed, and thus the read/write operations are delayed. We develop an optimization framework for RM-based register file on GPUs, which employs three different optimization techniques at the application, compilation, and architecture level, respectively. More clearly, we optimize the TLP at the application level, design a register mapping algorithm at the compilation level, and design a preshifting mechanism at the architecture level. Collectively, these optimizations help to determine the TLP without causing cache and register file resource contention and reduce the shift operation overhead. Experimental results using a variety of representative workloads demonstrate that our optimization framework achieves up to 29% （21% on average） performance improvement.
