In biomedical applications,the conventionally used metallic materials,including stainless steel,Co-based alloys and Ti alloys,often times exhibit unsatisfactory results such as stress shielding and metal ion releases....In biomedical applications,the conventionally used metallic materials,including stainless steel,Co-based alloys and Ti alloys,often times exhibit unsatisfactory results such as stress shielding and metal ion releases.Secondary surgical operation(s)usually become inevitable to prevent long term exposure of body with the toxic implant contents.The metallic biomaterials are being revolutionized with the development of biodegradable materials including several metals,alloys,and metallic glasses.As such,the nature of metallic biomaterials are transformed from the bioinert to bioactive and multi-biofunctional(anti-bacterial,anti-proliferation,anti-cancer,etc.).Magnesium-based biomaterials are candidates to be used as new generation biodegradable metals.Magnesium(Mg)can dissolve in body fluid that means the implanted Mg can degrade during healing process,and if the degradation is controlled it would leave no debris after the completion of healing.Hence,the need for secondary surgical operation(s)for the implant removal could be eliminated.Besides its biocompatibility,the inherent mechanical properties of Mg are very similar to those of human bone.Researchers have been working on synthesis and characterization of Mg-based biomaterials with a variety of composition in order to control the degradation rate of Mg since uncontrolled degradation could result in loss of mechanical integrity,metal contamination in the body and intolerable hydrogen evolution by tissue.It was observed that the applied methods of synthesis and the choice of components affect the characteristics and performance of the Mg-based biomaterials.Researchers have synthesized many Mg-based materials through several synthesis routes and investigated their mechanical properties,biocompatibility and degradation behavior through in vitro,in vivo and in silico studies.This paper is a comprehensive review that compiles,analyses and critically discusses the recent literature on the important aspects of Mg-based biomaterials.展开更多
A significant fraction of the conventional oil reserves globally is in carbonate formations which contain a substantial amount of residual oil. Since primary and secondary recovery methods fail to yield above 20%-40%o...A significant fraction of the conventional oil reserves globally is in carbonate formations which contain a substantial amount of residual oil. Since primary and secondary recovery methods fail to yield above 20%-40%of original oil in place from these reserves, the need for enhanced oil recovery（EOR） techniques for incremental oil recovery has become imperative. With the challenges presented by the highly heterogeneous carbonate rocks,evaluation of tertiary-stage recovery techniques including chemical EOR（c EOR） has been a high priority for researchers and oil producers. In this review, the latest developments in the surfactant-based c EOR techniques applied in carbonate formations are discussed, contemplating the future direction of existing methodologies. In connection with this, the characteristics of heterogeneous carbonate reservoirs are outlined. Detailed discussion on surfactant-led oil recovery mechanisms and related processes, such as wettability alteration, interfacial tension reduction, microemulsion phase behavior, surfactant adsorption and mitigation, and foams and their applications is presented. Laboratory experiments, as well as field study data obtained using several surfactants, are also included.This extensive discussion on the subject aims to help researchers and professionals in the field to understand the current situation and plan future enterprises accordingly.展开更多
Synthetic grafting needs improvements to eliminate secondary surgeries for the removal of implants after healing of the defected tissues.Tissue scaffolds are engineered to serve as temporary templates,which support th...Synthetic grafting needs improvements to eliminate secondary surgeries for the removal of implants after healing of the defected tissues.Tissue scaffolds are engineered to serve as temporary templates,which support the affected tissue and gradually degrade through the healing period.Beside mechanical function to withstand the anatomic loading conditions,scaffolds should also provide a decent biological function for the diffusion of nutrients and oxygen to the cells,and excretion of the wastes from the cells to promote the new tissue growth and vascularization.Moreover,the degradation byproducts of the scaffolds should be safe to the human body.Development of such multifunctional scaffolds requires selection of the right material,design,and manufacturing method.Mg has been recognized as the prominent biodegradable metal with regards to its mechanical properties matching to that of human bone,degradability in the body fluid,and its ability to stimulate new tissue growth.Scaffolds with intricate porous structures can be designed according to the patient-specific anatomic data using computer aided designs.Additive manufacturing(AM)is the right method to materialize these models rapidly with reasonably acceptable range of dimensional accuracy.Thus,the recent research trend is to develop ideal scaffolds using biodegradable Mg through AM methods.This review compiles and discusses the available literature on the AM of biodegradable Mg parts from the viewpoints of material compositions,process conditions,formation quality,dimensional accuracy,microstructure,biodegradation,and mechanical properties.The current achievements are summarized together,and future research directions are identified to promote clinical applications of biodegradable Mg through the advancement of AM.展开更多
Background:Progressive accumulation ofα-synuclein is a key step in the pathological development of Parkinson’s disease.Impaired protein degradation and increased levels ofα-synuclein may trigger a pathological aggr...Background:Progressive accumulation ofα-synuclein is a key step in the pathological development of Parkinson’s disease.Impaired protein degradation and increased levels ofα-synuclein may trigger a pathological aggregation in vitro and in vivo.The chaperone-mediated autophagy(CMA)pathway is involved in the intracellular degradation processes ofα-synuclein.Dysfunction of the CMA pathway impairsα-synuclein degradation and causes cytotoxicity.Results:In the present study,we investigated the effects on the CMA pathway andα-synuclein aggregation using bioactive ingredients(Dihydromyricetin(DHM)and Salvianolic acid B(Sal B))extracted from natural medicinal plants.In both cell-free and cellular models ofα-synuclein aggregation,after administration of DHM and Sal B,we observed significant inhibition ofα-synuclein accumulation and aggregation.Cells were co-transfected with a Cterminal modifiedα-synuclein(SynT)and synphilin-1,and then treated with DHM(10μM)and Sal B(50μM)16 hours after transfection;levels ofα-synuclein aggregation decreased significantly(68%for DHM and 75%for Sal B).Concomitantly,we detected increased levels of LAMP-1(a marker of lysosomal homeostasis)and LAMP-2A(a key marker of CMA).Immunofluorescence analyses showed increased colocalization between LAMP-1 and LAMP-2A withα-synuclein inclusions after treatment with DHM and Sal B.We also found increased levels of LAMP-1 and LAMP-2A both in vitro and in vivo,along with decreased levels ofα-synuclein.Moreover,DHM and Sal B treatments exhibited anti-inflammatory activities,preventing astroglia-and microglia-mediated neuroinflammation in BAC-α-syn-GFP transgenic mice.Conclusions:Our data indicate that DHM and Sal B are effective in modulatingα-synuclein accumulation and aggregate formation and augmenting activation of CMA,holding potential for the treatment of Parkinson’s disease.展开更多
Formation of acid mine drainage(AMD)is a widespread environmental issue that has not subsided throughout decades of continuing research.Highly acidic and highly concentrated metallic streams are characteristics of suc...Formation of acid mine drainage(AMD)is a widespread environmental issue that has not subsided throughout decades of continuing research.Highly acidic and highly concentrated metallic streams are characteristics of such streams.Humans,plants and surrounding ecosystems that are in proximity to AMD producing sites face immediate threats.Remediation options include active and passive biological treatments which are markedly different in many aspects.Sulfate reducing bacteria(SRB)remove sulfate and heavy metals to generate non-toxic streams.Passive systems are inexpensive to operate but entail fundamental drawbacks such as large land requirements and prolonged treatment period.Active bioreactors offer greater operational predictability and quicker treatment time but require higher investment costs and wide scale usage is limited by lack of expertise.Recent advancements include the use of renewable raw materials for AMD clean up purposes,which will likely achieve much greener mitigation solutions.展开更多
The merits of CO2 capture and storage to the environmental stability of our world should not be underestimated as emissions of greenhouse gases cause serious problems.It represents the only technology that might rid o...The merits of CO2 capture and storage to the environmental stability of our world should not be underestimated as emissions of greenhouse gases cause serious problems.It represents the only technology that might rid our atmosphere of the main anthropogenic gas while allowing for the continuous use of the fossil fuels which still power today’s world.Underground storage of CO2 involves the injection of CO2 into suitable geological formations and the monitoring of the injected plume over time,to ensure containment.Over the last two or three decades,attention has been paid to technology developments of carbon capture and sequestration.Therefore,it is high time to look at the research done so far.In this regard,a high-level review article is required to provide an overview of the status of carbon capture and sequestration research.This article presents a review of CO2 storage technologies which includes a background of essential concepts in storage,the physical processes involved,modeling procedures and simulators used,capacity estimation,measuring monitoring and verification techniques,risks and challenges involved and field-/pilot-scale projects.It is expected that the present review paper will help the researchers to gain a quick knowledge of CO2 sequestration for future research in this field.展开更多
The removal of copper ions from wastewater by ion exchange has been studied using an iminodiacetate resin.The capacity of the resin for the copper ions has been determined to be 2.30 mmol·g^(-1) by measuring the ...The removal of copper ions from wastewater by ion exchange has been studied using an iminodiacetate resin.The capacity of the resin for the copper ions has been determined to be 2.30 mmol·g^(-1) by measuring the equilibrium isotherm at 25 °C and initial pH value of 3.5 where the final equilibrium p H value is 5. An analysis of equilibrium isotherm models showed that the best fit model was the Langmuir–Freundlich. The kinetics of the ion exchange process have been investigated and four kinetic models have been tested namely: Ritchie model, pseudo-second order model, pseudo-first order model and the Elovich model. The pseudo-second order model provides the best fit to the kinetic data.展开更多
Although VEGF-B was discovered as a VEGF-A homolog a long time ago,the angiogenic effect of VEGF-B remains poorly understood with limited and diverse findings from different groups.Notwithstanding,drugs that inhibit V...Although VEGF-B was discovered as a VEGF-A homolog a long time ago,the angiogenic effect of VEGF-B remains poorly understood with limited and diverse findings from different groups.Notwithstanding,drugs that inhibit VEGF-B together with other VEGF family members are being used to treat patients with various neovascular diseases.It is therefore critical to have a better understanding of the angiogenic effect of VEGF-B and the underlying mechanisms.Using comprehensive in vitro and in vivo methods and models,we reveal here for the first time an unexpected and surprising function of VEGF-B as an endogenous inhibitor of angiogenesis by inhibiting the FGF2/FGFR1 pathway when the latter is abundantly expressed.Mechanistically,we unveil that VEGF-B binds to FGFR1,induces FGFR1/VEGFR1 complex formation,and suppresses FGF2-induced Erk activation,and inhibits FGF2-driven angiogenesis and tumor growth.Our work uncovers a previously unrecognized novel function of VEGF-B in tethering the FGF2/FGFR1 pathway.Given the anti-angiogenic nature of VEGF-B under conditions of high FGF2/FGFR1 levels,caution is warranted when modulating VEGF-B activity to treat neovascular diseases.展开更多
Background:Fever of unknown origin(FUO)in developing countries is an important dilemma and further research is needed to elucidate the infectious causes of FUO.Methods:A multi-center study for infectious causes of FUO...Background:Fever of unknown origin(FUO)in developing countries is an important dilemma and further research is needed to elucidate the infectious causes of FUO.Methods:A multi-center study for infectious causes of FUO in lower middle-income countries(LMIC)and lowincome countries(LIC)was conducted between January 1,2018 and January 1,2023.In total,15 participating centers from seven different countries provided the data,which were collected through the Infectious DiseasesInternational Research Initiative platform.Only adult patients with confirmed infection as the cause of FUO were included in the study.The severity parameters were quick Sequential Organ Failure Assessment(qSOFA)≥2,intensive care unit(ICU)admission,vasopressor use,and invasive mechanical ventilation(IMV).Results:A total of 160 patients with infectious FUO were included in the study.Overall,148(92.5%)patients had community-acquired infections and 12(7.5%)had hospital-acquired infections.The most common infectious syndromes were tuberculosis(TB)(n=27,16.9%),infective endocarditis(n=25,15.6%),malaria(n=21,13.1%),brucellosis(n=15,9.4%),and typhoid fever(n=9,5.6%).Plasmodium falciparum,Mycobacterium tuberculosis,Brucellae,Staphylococcus aureus,Salmonella typhi,and Rickettsiae were the leading infectious agents in this study.A total of 56(35.0%)cases had invasive procedures for diagnosis.The mean qSOFA score was 0.76±0.94{median(interquartile range[IQR]):0(0–1)}.ICU admission(n=26,16.2%),vasopressor use(n=14,8.8%),and IMV(n=10,6.3%)were not rare.Overall,38(23.8%)patients had at least one of the severity parameters.The mortality rate was 15(9.4%),and the mortality was attributable to the infection causing FUO in 12(7.5%)patients.Conclusions:In LMIC and LIC,tuberculosis and cardiac infections were the most severe and the leading infections causing FUO.展开更多
G protein-coupled receptors(GPCRs)represent the most substantial family of membrane receptors that are targeted by U.S.Food and Drug Administration-approved drugs.Much of the preclinical research to understand the pha...G protein-coupled receptors(GPCRs)represent the most substantial family of membrane receptors that are targeted by U.S.Food and Drug Administration-approved drugs.Much of the preclinical research to understand the pharmacology of many membrane receptors including GPCRs is derived from studies in male animal models(Karp and Reavey,2019).展开更多
A Machine Learning (ML)-based Intrusion Detection and Prevention System (IDPS)requires a large amount of labeled up-to-date training data to effectively detect intrusions and generalize well to novel attacks.However,t...A Machine Learning (ML)-based Intrusion Detection and Prevention System (IDPS)requires a large amount of labeled up-to-date training data to effectively detect intrusions and generalize well to novel attacks.However,the labeling of data is costly and becomes infeasible when dealing with big data,such as those generated by Intemet of Things applications.To this effect,building an ML model that learns from non-labeled or partially labeled data is of critical importance.This paper proposes a Semi-supervised Mniti-Layered Clustering ((SMLC))model for the detection and prevention of network intrusion.SMLC has the capability to learn from partially labeled data while achieving a detection performance comparable to that of supervised ML-based IDPS.The performance of SMLC is compared with that of a well-known semi-supervised model (tri-training)and of supervised ensemble ML models, namely Random.Forest,Bagging,and AdaboostM1on two benchmark network-intrusion datasets,NSL and Kyoto 2006+.Experimental resnits show that SMLC is superior to tri-training,providing a comparable detection accuracy with 20%less labeled instances of training data.Furthermore,our results demonstrate that our scheme has a detection accuracy comparable to that of the supervised ensemble models.展开更多
In the last years,several countries have been devastated by natural disasters,resulting in thousands of casualties and injuries.Rescue missions were quick to respond to the needs of many devasted regions,providing cri...In the last years,several countries have been devastated by natural disasters,resulting in thousands of casualties and injuries.Rescue missions were quick to respond to the needs of many devasted regions,providing critical interventions,life support equipment,and vital pharmaceuticals.However,rescue missions are still relying on traditional emergency equipment and tools that do not always have the capacity for critical diagnosis in disaster areas.展开更多
Flexible and free-standing electrospun nanofibres have been used as electrode materials in electrochemical energy storage systems due to their versatile properties,such as mechanical stability,superb electrical conduc...Flexible and free-standing electrospun nanofibres have been used as electrode materials in electrochemical energy storage systems due to their versatile properties,such as mechanical stability,superb electrical conductivity,and high functionality.In energy storage systems such as metal-ion,metal-air,and metal-sulphur batteries,electrospun nanofibres are vital for constructing flexible electrodes and substantially enhancing their electrochemical properties.The need for flexible batteries has increased with increasing demand for new products such as wearable and flexible devices,including smartwatches and flexible displays.Conventional batteries have several semirigid to rigid components that limit their expansion in the flexible device market.The creation of flexible and wearable batteries with greater mechanical flexibility,higher energy,and substantial power density is critical in meeting the demand for these new electronic items.The implementation of carbon and carbon-derived composites into flexible electrodes is required to realize this goal.It is essential to understand recent advances and the comprehensive foundation behind the synthesis and assembly of various flexible electrospun nanofibres.The design of nanofibres,including those comprising carbon,N-doped carbon,hierarchical,porous carbon,and metal/metal oxide carbon composites,will be explored.We will highlight the merits of electrospun carbon flexible electrodes by describing porosity,surface area,binder-free and free-standing electrode construction,cycling stability,and performance rate.Significant scientific progress has been achieved and logistical challenges have been met in promoting secondary battery usage;therefore,this review of flexible electrode materials will advance this easily used and sought-after technology.The challenges and prospects involved in the timely development of carbon nanofibre composite flexible electrodes and batteries will be addressed.展开更多
This paper reviews the various control algorithms and strategies used for fixed-wing morphing aircraft applications. It is evident from the literature that the development of control algorithms for morphing aircraft t...This paper reviews the various control algorithms and strategies used for fixed-wing morphing aircraft applications. It is evident from the literature that the development of control algorithms for morphing aircraft technologies focused on three main areas. The first area is related to precise control of the shape of morphing concepts for various flight conditions. The second area is mainly related to the flight dynamics, stability, and control aspects of morphing aircraft. The third area deals mainly with aeroelastic control using morphing concepts either for load alleviation purposes and/or to control the instability boundaries. The design of controllers for morphing aircraft/wings is very challenging due to the large changes that can occur in the structural, aerodynamic, and inertial characteristics. In addition, the type of actuation system and actuation rate/speed can have a significant effect on the design of such controllers. The aerospace community is in strong need of such a critical review especially as morphing aircraft technologies move from fundamental research at a low Technology Readiness Level(TRL) to real-life applications. This critical review aims to identify research gaps and propose future directions. In this paper, research activities/papers are categorized according to the control strategy used. This ranges from simple Proportional Integral Derivative(PID) controllers at one end to complex robust adaptive controllers and deep learning algorithms at the other end. This includes analytical, computational, and experimental studies. In addition, the various dynamic models used and their fidelities are highlighted and discussed.展开更多
Eosinophilic esophagitis is a newly recognized disease first described about 50 years ago.The definition,diagnosis,and management have evolved with new published consensus guidelines and newly approved treatment avail...Eosinophilic esophagitis is a newly recognized disease first described about 50 years ago.The definition,diagnosis,and management have evolved with new published consensus guidelines and newly approved treatment available to pediatricians,enabling a better understanding of this disease and more targeted treatment for patients.We describe the definition,presentation,and diagnosis of eosinophilic esophagitis including management,challenges,and future directions in children.The definition,diagnosis,and management of eosinophilic esophagitis have evolved over the last 50 years.Consensus guidelines and newly approved biologic treatment have enabled pediatricians to better understand this disease and allow for more targeted treatment for patients.We describe the definition,presentation,diagnosis,management,and treatment in addition to the challenges and future directions of eosinophilic esophagitis management in children.展开更多
MXene has been the limelight for studies on electrode active materials,aiming at developing supercapacitors with boosted energy density to meet the emerging influx of wearable and portable electronic devices.Despite i...MXene has been the limelight for studies on electrode active materials,aiming at developing supercapacitors with boosted energy density to meet the emerging influx of wearable and portable electronic devices.Despite its various desirable properties including intrinsic flexibility,high specific surface area,excellent metallic conductivity and unique abundance of surface functionalities,its full potential for electrochemical performance is hindered by the notorious restacking phenomenon of MXene nanosheets.Ascribed to its two-dimensional(2D)nature and surface functional groups,inevitable Van der Waals interactions drive the agglomeration of nanosheets,ultimately reducing the exposure of electrochemically active sites to the electrolyte,as well as severely lengthening electrolyte ion transport pathways.As a result,energy and power density deteriorate,limiting the application versatility of MXene-based supercapacitors.Constructing 3D architectures using 2D nanosheets presents as a straightforward yet ingenious approach to mitigate the fatal flaws of MXene.However,the sheer number of distinct methodologies reported,thus far,calls for a systematic review that unravels the rationale behind such 3D MXene structural designs.Herein,this review aims to serve this purpose while also scrutinizing the structure–property relationship to correlate such structural modifications to their ensuing electrochemical performance enhancements.Besides,the physicochemical properties of MXene play fundamental roles in determining the effective charge storage capabilities of 3D MXene-based electrodes.This largely depends on different MXene synthesis techniques and synthesis condition variations,hence,elucidated in this review as well.Lastly,the challenges and perspectives for achieving viable commercialization of MXene-based supercapacitor electrodes are highlighted.展开更多
Reducing the production costs of clean energy carriers such as hydrogen through scalable water electrolysis is a potential solution for advancing the hydrogen economy.Among the various material candidates,our group de...Reducing the production costs of clean energy carriers such as hydrogen through scalable water electrolysis is a potential solution for advancing the hydrogen economy.Among the various material candidates,our group demonstrated transition-metal-based materials with tunable electronic characteristics,various phases,and earth-abundance.Herein,electrochemical water oxidation using Cu_(2)Se-V_(2)O_(5) as a non-precious metallic electrocatalyst via a hydrothermal approach is reported.The water-splitting performance of all the fabricated electrocatalysts was evaluated after direct growth on a stainless-steel substrate.The electrochemically tuned Cu_(2)Se-V_(2)O_(5) catalyst exhibited a reduced overpotential of 128 mV and provided a reduced Tafel slope of 57 mV·dec^(−1) to meet the maximum current density of 250 mA·cm^(−2).The optimized strategy for interfacial coupling of the fabricated Cu_(2)Se-V_(2)O_(5) catalyst resulted in a porous structure with accessible active sites,which enabled adsorption of the intermediates and afforded an effective charge transfer rate for promoting the oxygen evolution reaction.Furthermore,the combined effect of the catalyst components provided long-term stability for over 110 h in an alkaline solution,which makes the catalyst promising for large-scale practical applications.The aforementioned advantages of the composite catalyst overcome the limitations of low conductivity,agglomeration,and poor stability of the pure catalysts(Cu2Se and V2O5).展开更多
This paper presents the development of a novel compliant polymorphing wing capable of chord and camber morphing for small UAVs.The morphing wing can achieve up to 10%chord extension and±20°camber changes.The...This paper presents the development of a novel compliant polymorphing wing capable of chord and camber morphing for small UAVs.The morphing wing can achieve up to 10%chord extension and±20°camber changes.The design,modeling,sizing,manufacturing and mechanical testing of the wing are detailed.The polymorphing wing consists of one continuous front spar fixed to the fuselage and a rear spar on each side of the wing.Each rear spar can translate in the chordwise direction(chord morphing)and rotate around itself(camber morphing).A flexible elastomeric latex sheet is used as the skin to cover the wing and maintain its aerodynamic shape whilst allowing morphing.The loads from the skin are transferred to the spars using the compliant cellular ribs that support the flexible skin and facilitate morphing.Pre-tensioning is applied to the skin to minimize wrinkling when subject to aerodynamic and actuation loads.A rack and pinion actuation system,powered by stepper motors,is used for morphing.Aero-structural design,analysis and sizing are conducted.Performance comparison between the polymorphing wing and the baseline wing(non-morphing)shows that chord morphing improves aerodynamic efficiency at low angles of attack while camber morphing improves efficiency at high angles of attack.展开更多
A new feature extraction technique for the detection of lesions created from mucosal inflammations in Crohn's disease, based on wireless capsule endoscopy(WCE) images processing is presented here. More specificall...A new feature extraction technique for the detection of lesions created from mucosal inflammations in Crohn's disease, based on wireless capsule endoscopy(WCE) images processing is presented here. More specifically, a novel filtering process, namely Hybrid Adaptive Filtering(HAF), was developed for efficient extraction of lesion-related structural/textural characteristics from WCE images, by employing Genetic Algorithms to the Curvelet-based representation of images. Additionally, Differential Lacunarity(DLac) analysis was applied for feature extraction from the HAF-filtered images. The resulted scheme, namely HAF-DLac, incorporates support vector machines for robust lesion recognition performance. For the training and testing of HAFDLac, an 800-image database was used, acquired from 13 patients who undertook WCE examinations, where the abnormal cases were grouped into mild and severe, according to the severity of the depicted lesion, for a more extensive evaluation of the performance. Experimental results, along with comparison with other related efforts, have shown that the HAF-DLac approach evidently outperforms them in the field of WCE image analysis for automated lesion detection, providing higher classification results, up to 93.8%(accuracy), 95.2%(sensitivity), 92.4%(specificity) and 92.6%(precision). The promising performance of HAF-DLac paves the way for a complete computer-aided diagnosis system that could support physicians' clinical practice.展开更多
文摘In biomedical applications,the conventionally used metallic materials,including stainless steel,Co-based alloys and Ti alloys,often times exhibit unsatisfactory results such as stress shielding and metal ion releases.Secondary surgical operation(s)usually become inevitable to prevent long term exposure of body with the toxic implant contents.The metallic biomaterials are being revolutionized with the development of biodegradable materials including several metals,alloys,and metallic glasses.As such,the nature of metallic biomaterials are transformed from the bioinert to bioactive and multi-biofunctional(anti-bacterial,anti-proliferation,anti-cancer,etc.).Magnesium-based biomaterials are candidates to be used as new generation biodegradable metals.Magnesium(Mg)can dissolve in body fluid that means the implanted Mg can degrade during healing process,and if the degradation is controlled it would leave no debris after the completion of healing.Hence,the need for secondary surgical operation(s)for the implant removal could be eliminated.Besides its biocompatibility,the inherent mechanical properties of Mg are very similar to those of human bone.Researchers have been working on synthesis and characterization of Mg-based biomaterials with a variety of composition in order to control the degradation rate of Mg since uncontrolled degradation could result in loss of mechanical integrity,metal contamination in the body and intolerable hydrogen evolution by tissue.It was observed that the applied methods of synthesis and the choice of components affect the characteristics and performance of the Mg-based biomaterials.Researchers have synthesized many Mg-based materials through several synthesis routes and investigated their mechanical properties,biocompatibility and degradation behavior through in vitro,in vivo and in silico studies.This paper is a comprehensive review that compiles,analyses and critically discusses the recent literature on the important aspects of Mg-based biomaterials.
文摘A significant fraction of the conventional oil reserves globally is in carbonate formations which contain a substantial amount of residual oil. Since primary and secondary recovery methods fail to yield above 20%-40%of original oil in place from these reserves, the need for enhanced oil recovery（EOR） techniques for incremental oil recovery has become imperative. With the challenges presented by the highly heterogeneous carbonate rocks,evaluation of tertiary-stage recovery techniques including chemical EOR（c EOR） has been a high priority for researchers and oil producers. In this review, the latest developments in the surfactant-based c EOR techniques applied in carbonate formations are discussed, contemplating the future direction of existing methodologies. In connection with this, the characteristics of heterogeneous carbonate reservoirs are outlined. Detailed discussion on surfactant-led oil recovery mechanisms and related processes, such as wettability alteration, interfacial tension reduction, microemulsion phase behavior, surfactant adsorption and mitigation, and foams and their applications is presented. Laboratory experiments, as well as field study data obtained using several surfactants, are also included.This extensive discussion on the subject aims to help researchers and professionals in the field to understand the current situation and plan future enterprises accordingly.
文摘Synthetic grafting needs improvements to eliminate secondary surgeries for the removal of implants after healing of the defected tissues.Tissue scaffolds are engineered to serve as temporary templates,which support the affected tissue and gradually degrade through the healing period.Beside mechanical function to withstand the anatomic loading conditions,scaffolds should also provide a decent biological function for the diffusion of nutrients and oxygen to the cells,and excretion of the wastes from the cells to promote the new tissue growth and vascularization.Moreover,the degradation byproducts of the scaffolds should be safe to the human body.Development of such multifunctional scaffolds requires selection of the right material,design,and manufacturing method.Mg has been recognized as the prominent biodegradable metal with regards to its mechanical properties matching to that of human bone,degradability in the body fluid,and its ability to stimulate new tissue growth.Scaffolds with intricate porous structures can be designed according to the patient-specific anatomic data using computer aided designs.Additive manufacturing(AM)is the right method to materialize these models rapidly with reasonably acceptable range of dimensional accuracy.Thus,the recent research trend is to develop ideal scaffolds using biodegradable Mg through AM methods.This review compiles and discusses the available literature on the AM of biodegradable Mg parts from the viewpoints of material compositions,process conditions,formation quality,dimensional accuracy,microstructure,biodegradation,and mechanical properties.The current achievements are summarized together,and future research directions are identified to promote clinical applications of biodegradable Mg through the advancement of AM.
基金We would like to acknowledge financial supports by the National Natural Science Foundation(81430025,81701265,31800898,U801681)Acknowledgements are also to the supports of the Swedish Research Council(K2015-61X-22297-03-4)+2 种基金EU-JPND(aSynProtec),EU-JPND(REfrAME),EU H2020-MSCA-ITN-2016(Syndegen),BAGADILICO-Excellence in Parkinson and Huntington Research,the Strong Research Environment MultiPark(Multidisciplinary research on Parkinson’s disease),the Swedish Parkinson Foundation(Parkinsonfonden),Torsten Söderbergs Foundation,Olle Engkvist Byggmästere FoundationW.L.is supported by a scholarship from the China Scholarship CouncilTFO is supported by the DFG Center for Nanoscaly Microscopy and Molecular Physiology of the Brain(CNMPB).
文摘Background:Progressive accumulation ofα-synuclein is a key step in the pathological development of Parkinson’s disease.Impaired protein degradation and increased levels ofα-synuclein may trigger a pathological aggregation in vitro and in vivo.The chaperone-mediated autophagy(CMA)pathway is involved in the intracellular degradation processes ofα-synuclein.Dysfunction of the CMA pathway impairsα-synuclein degradation and causes cytotoxicity.Results:In the present study,we investigated the effects on the CMA pathway andα-synuclein aggregation using bioactive ingredients(Dihydromyricetin(DHM)and Salvianolic acid B(Sal B))extracted from natural medicinal plants.In both cell-free and cellular models ofα-synuclein aggregation,after administration of DHM and Sal B,we observed significant inhibition ofα-synuclein accumulation and aggregation.Cells were co-transfected with a Cterminal modifiedα-synuclein(SynT)and synphilin-1,and then treated with DHM(10μM)and Sal B(50μM)16 hours after transfection;levels ofα-synuclein aggregation decreased significantly(68%for DHM and 75%for Sal B).Concomitantly,we detected increased levels of LAMP-1(a marker of lysosomal homeostasis)and LAMP-2A(a key marker of CMA).Immunofluorescence analyses showed increased colocalization between LAMP-1 and LAMP-2A withα-synuclein inclusions after treatment with DHM and Sal B.We also found increased levels of LAMP-1 and LAMP-2A both in vitro and in vivo,along with decreased levels ofα-synuclein.Moreover,DHM and Sal B treatments exhibited anti-inflammatory activities,preventing astroglia-and microglia-mediated neuroinflammation in BAC-α-syn-GFP transgenic mice.Conclusions:Our data indicate that DHM and Sal B are effective in modulatingα-synuclein accumulation and aggregate formation and augmenting activation of CMA,holding potential for the treatment of Parkinson’s disease.
基金supported by the Fundamental Research Grant Scheme,Malaysia[FRGS/1/2019/STG05/UNIM/02/2].
文摘Formation of acid mine drainage(AMD)is a widespread environmental issue that has not subsided throughout decades of continuing research.Highly acidic and highly concentrated metallic streams are characteristics of such streams.Humans,plants and surrounding ecosystems that are in proximity to AMD producing sites face immediate threats.Remediation options include active and passive biological treatments which are markedly different in many aspects.Sulfate reducing bacteria(SRB)remove sulfate and heavy metals to generate non-toxic streams.Passive systems are inexpensive to operate but entail fundamental drawbacks such as large land requirements and prolonged treatment period.Active bioreactors offer greater operational predictability and quicker treatment time but require higher investment costs and wide scale usage is limited by lack of expertise.Recent advancements include the use of renewable raw materials for AMD clean up purposes,which will likely achieve much greener mitigation solutions.
基金support provided by the Department of Petroleum Engineering,Khalifa University of Science and Technology,Sas Al Nakhl Campus,Abu Dhabi,UAE
文摘The merits of CO2 capture and storage to the environmental stability of our world should not be underestimated as emissions of greenhouse gases cause serious problems.It represents the only technology that might rid our atmosphere of the main anthropogenic gas while allowing for the continuous use of the fossil fuels which still power today’s world.Underground storage of CO2 involves the injection of CO2 into suitable geological formations and the monitoring of the injected plume over time,to ensure containment.Over the last two or three decades,attention has been paid to technology developments of carbon capture and sequestration.Therefore,it is high time to look at the research done so far.In this regard,a high-level review article is required to provide an overview of the status of carbon capture and sequestration research.This article presents a review of CO2 storage technologies which includes a background of essential concepts in storage,the physical processes involved,modeling procedures and simulators used,capacity estimation,measuring monitoring and verification techniques,risks and challenges involved and field-/pilot-scale projects.It is expected that the present review paper will help the researchers to gain a quick knowledge of CO2 sequestration for future research in this field.
文摘The removal of copper ions from wastewater by ion exchange has been studied using an iminodiacetate resin.The capacity of the resin for the copper ions has been determined to be 2.30 mmol·g^(-1) by measuring the equilibrium isotherm at 25 °C and initial pH value of 3.5 where the final equilibrium p H value is 5. An analysis of equilibrium isotherm models showed that the best fit model was the Langmuir–Freundlich. The kinetics of the ion exchange process have been investigated and four kinetic models have been tested namely: Ritchie model, pseudo-second order model, pseudo-first order model and the Elovich model. The pseudo-second order model provides the best fit to the kinetic data.
基金This study is supported by the State Key Laboratory of Ophthalmology,Zhongshan Ophthalmic Center,Sun Yat-sen University,and Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science,Guangzhou 510060,P.R.Chinathe National Natural Science Foundation of China(82150710555 and 82220108016 to X.Li,81970823 to Jin Yao and 81830013 to J.O.)+4 种基金a Key Research and Development Plan of Shandong Province(2016GSF201100)the Fundamental Research Funds for the Central Universities(19ykpy151)the long-term structural Methusalem funding by the Flemish Government,Belgiumthe Deutsche Forschungsge-meinschaft(Project No.:394046768-SFB1366)the DZHK partner site Mannheim/Heidelberg to H.F.L.,an ERA PerMed 2020 JTC grant“PROGRESS”.
文摘Although VEGF-B was discovered as a VEGF-A homolog a long time ago,the angiogenic effect of VEGF-B remains poorly understood with limited and diverse findings from different groups.Notwithstanding,drugs that inhibit VEGF-B together with other VEGF family members are being used to treat patients with various neovascular diseases.It is therefore critical to have a better understanding of the angiogenic effect of VEGF-B and the underlying mechanisms.Using comprehensive in vitro and in vivo methods and models,we reveal here for the first time an unexpected and surprising function of VEGF-B as an endogenous inhibitor of angiogenesis by inhibiting the FGF2/FGFR1 pathway when the latter is abundantly expressed.Mechanistically,we unveil that VEGF-B binds to FGFR1,induces FGFR1/VEGFR1 complex formation,and suppresses FGF2-induced Erk activation,and inhibits FGF2-driven angiogenesis and tumor growth.Our work uncovers a previously unrecognized novel function of VEGF-B in tethering the FGF2/FGFR1 pathway.Given the anti-angiogenic nature of VEGF-B under conditions of high FGF2/FGFR1 levels,caution is warranted when modulating VEGF-B activity to treat neovascular diseases.
文摘Background:Fever of unknown origin(FUO)in developing countries is an important dilemma and further research is needed to elucidate the infectious causes of FUO.Methods:A multi-center study for infectious causes of FUO in lower middle-income countries(LMIC)and lowincome countries(LIC)was conducted between January 1,2018 and January 1,2023.In total,15 participating centers from seven different countries provided the data,which were collected through the Infectious DiseasesInternational Research Initiative platform.Only adult patients with confirmed infection as the cause of FUO were included in the study.The severity parameters were quick Sequential Organ Failure Assessment(qSOFA)≥2,intensive care unit(ICU)admission,vasopressor use,and invasive mechanical ventilation(IMV).Results:A total of 160 patients with infectious FUO were included in the study.Overall,148(92.5%)patients had community-acquired infections and 12(7.5%)had hospital-acquired infections.The most common infectious syndromes were tuberculosis(TB)(n=27,16.9%),infective endocarditis(n=25,15.6%),malaria(n=21,13.1%),brucellosis(n=15,9.4%),and typhoid fever(n=9,5.6%).Plasmodium falciparum,Mycobacterium tuberculosis,Brucellae,Staphylococcus aureus,Salmonella typhi,and Rickettsiae were the leading infectious agents in this study.A total of 56(35.0%)cases had invasive procedures for diagnosis.The mean qSOFA score was 0.76±0.94{median(interquartile range[IQR]):0(0–1)}.ICU admission(n=26,16.2%),vasopressor use(n=14,8.8%),and IMV(n=10,6.3%)were not rare.Overall,38(23.8%)patients had at least one of the severity parameters.The mortality rate was 15(9.4%),and the mortality was attributable to the infection causing FUO in 12(7.5%)patients.Conclusions:In LMIC and LIC,tuberculosis and cardiac infections were the most severe and the leading infections causing FUO.
基金supported by a New Investigator grant fram the Alzheimer’s Society of Canada and Alzheimer Disease Research Grant from Djavad Mowafaghian Centre for Brain Health(to KSAE)。
文摘G protein-coupled receptors(GPCRs)represent the most substantial family of membrane receptors that are targeted by U.S.Food and Drug Administration-approved drugs.Much of the preclinical research to understand the pharmacology of many membrane receptors including GPCRs is derived from studies in male animal models(Karp and Reavey,2019).
文摘A Machine Learning (ML)-based Intrusion Detection and Prevention System (IDPS)requires a large amount of labeled up-to-date training data to effectively detect intrusions and generalize well to novel attacks.However,the labeling of data is costly and becomes infeasible when dealing with big data,such as those generated by Intemet of Things applications.To this effect,building an ML model that learns from non-labeled or partially labeled data is of critical importance.This paper proposes a Semi-supervised Mniti-Layered Clustering ((SMLC))model for the detection and prevention of network intrusion.SMLC has the capability to learn from partially labeled data while achieving a detection performance comparable to that of supervised ML-based IDPS.The performance of SMLC is compared with that of a well-known semi-supervised model (tri-training)and of supervised ensemble ML models, namely Random.Forest,Bagging,and AdaboostM1on two benchmark network-intrusion datasets,NSL and Kyoto 2006+.Experimental resnits show that SMLC is superior to tri-training,providing a comparable detection accuracy with 20%less labeled instances of training data.Furthermore,our results demonstrate that our scheme has a detection accuracy comparable to that of the supervised ensemble models.
文摘In the last years,several countries have been devastated by natural disasters,resulting in thousands of casualties and injuries.Rescue missions were quick to respond to the needs of many devasted regions,providing critical interventions,life support equipment,and vital pharmaceuticals.However,rescue missions are still relying on traditional emergency equipment and tools that do not always have the capacity for critical diagnosis in disaster areas.
基金supported by the National Natural Science Foundation of China(51871119,51901100,22075141)High-Level Entrepreneurial and Innovative Talents Program of Jiangsu Province,NSFC-Yunnan Joint Foundation(U2002213)+5 种基金Double Tops Joint Fund of the Yunnan Science and Technology Bureau and Yunnan University(2019FY003025)Jiangsu Provincial Funds for Natural Science Foundation(BK20170793,BK20180015)Six Talent Peak Project of Jiangsu Province(2018-XCL-033)China Postdoctoral Science Foundation(2018M640481)Jiangsu-Innovate UK Business Competition(BZ2017061)Double Tops Joint Fund of the Yunnan Science and Technology Bureau and Yunnan University(2019FY003025).
文摘Flexible and free-standing electrospun nanofibres have been used as electrode materials in electrochemical energy storage systems due to their versatile properties,such as mechanical stability,superb electrical conductivity,and high functionality.In energy storage systems such as metal-ion,metal-air,and metal-sulphur batteries,electrospun nanofibres are vital for constructing flexible electrodes and substantially enhancing their electrochemical properties.The need for flexible batteries has increased with increasing demand for new products such as wearable and flexible devices,including smartwatches and flexible displays.Conventional batteries have several semirigid to rigid components that limit their expansion in the flexible device market.The creation of flexible and wearable batteries with greater mechanical flexibility,higher energy,and substantial power density is critical in meeting the demand for these new electronic items.The implementation of carbon and carbon-derived composites into flexible electrodes is required to realize this goal.It is essential to understand recent advances and the comprehensive foundation behind the synthesis and assembly of various flexible electrospun nanofibres.The design of nanofibres,including those comprising carbon,N-doped carbon,hierarchical,porous carbon,and metal/metal oxide carbon composites,will be explored.We will highlight the merits of electrospun carbon flexible electrodes by describing porosity,surface area,binder-free and free-standing electrode construction,cycling stability,and performance rate.Significant scientific progress has been achieved and logistical challenges have been met in promoting secondary battery usage;therefore,this review of flexible electrode materials will advance this easily used and sought-after technology.The challenges and prospects involved in the timely development of carbon nanofibre composite flexible electrodes and batteries will be addressed.
基金funded by Abu Dhabi Education Council Award for Research Excellence Program (AARE 2019) _(No. AARE19-213)by Khalifa University of Science and Technology through Faculty Start-up Award (No. FSU-2020-20)。
文摘This paper reviews the various control algorithms and strategies used for fixed-wing morphing aircraft applications. It is evident from the literature that the development of control algorithms for morphing aircraft technologies focused on three main areas. The first area is related to precise control of the shape of morphing concepts for various flight conditions. The second area is mainly related to the flight dynamics, stability, and control aspects of morphing aircraft. The third area deals mainly with aeroelastic control using morphing concepts either for load alleviation purposes and/or to control the instability boundaries. The design of controllers for morphing aircraft/wings is very challenging due to the large changes that can occur in the structural, aerodynamic, and inertial characteristics. In addition, the type of actuation system and actuation rate/speed can have a significant effect on the design of such controllers. The aerospace community is in strong need of such a critical review especially as morphing aircraft technologies move from fundamental research at a low Technology Readiness Level(TRL) to real-life applications. This critical review aims to identify research gaps and propose future directions. In this paper, research activities/papers are categorized according to the control strategy used. This ranges from simple Proportional Integral Derivative(PID) controllers at one end to complex robust adaptive controllers and deep learning algorithms at the other end. This includes analytical, computational, and experimental studies. In addition, the various dynamic models used and their fidelities are highlighted and discussed.
文摘Eosinophilic esophagitis is a newly recognized disease first described about 50 years ago.The definition,diagnosis,and management have evolved with new published consensus guidelines and newly approved treatment available to pediatricians,enabling a better understanding of this disease and more targeted treatment for patients.We describe the definition,presentation,and diagnosis of eosinophilic esophagitis including management,challenges,and future directions in children.The definition,diagnosis,and management of eosinophilic esophagitis have evolved over the last 50 years.Consensus guidelines and newly approved biologic treatment have enabled pediatricians to better understand this disease and allow for more targeted treatment for patients.We describe the definition,presentation,diagnosis,management,and treatment in addition to the challenges and future directions of eosinophilic esophagitis management in children.
基金supported by the Fundamental Research Grant Scheme by Ministry of Higher Education Malaysia(FRGS/1/2021/STG04/XMU/02/1 and FRGS/1/2022/TK09/XMU/03/2)the Xiamen University Malaysia Research Fund(XMUMRF/2023-C11/IENG/0056)。
文摘MXene has been the limelight for studies on electrode active materials,aiming at developing supercapacitors with boosted energy density to meet the emerging influx of wearable and portable electronic devices.Despite its various desirable properties including intrinsic flexibility,high specific surface area,excellent metallic conductivity and unique abundance of surface functionalities,its full potential for electrochemical performance is hindered by the notorious restacking phenomenon of MXene nanosheets.Ascribed to its two-dimensional(2D)nature and surface functional groups,inevitable Van der Waals interactions drive the agglomeration of nanosheets,ultimately reducing the exposure of electrochemically active sites to the electrolyte,as well as severely lengthening electrolyte ion transport pathways.As a result,energy and power density deteriorate,limiting the application versatility of MXene-based supercapacitors.Constructing 3D architectures using 2D nanosheets presents as a straightforward yet ingenious approach to mitigate the fatal flaws of MXene.However,the sheer number of distinct methodologies reported,thus far,calls for a systematic review that unravels the rationale behind such 3D MXene structural designs.Herein,this review aims to serve this purpose while also scrutinizing the structure–property relationship to correlate such structural modifications to their ensuing electrochemical performance enhancements.Besides,the physicochemical properties of MXene play fundamental roles in determining the effective charge storage capabilities of 3D MXene-based electrodes.This largely depends on different MXene synthesis techniques and synthesis condition variations,hence,elucidated in this review as well.Lastly,the challenges and perspectives for achieving viable commercialization of MXene-based supercapacitor electrodes are highlighted.
文摘Reducing the production costs of clean energy carriers such as hydrogen through scalable water electrolysis is a potential solution for advancing the hydrogen economy.Among the various material candidates,our group demonstrated transition-metal-based materials with tunable electronic characteristics,various phases,and earth-abundance.Herein,electrochemical water oxidation using Cu_(2)Se-V_(2)O_(5) as a non-precious metallic electrocatalyst via a hydrothermal approach is reported.The water-splitting performance of all the fabricated electrocatalysts was evaluated after direct growth on a stainless-steel substrate.The electrochemically tuned Cu_(2)Se-V_(2)O_(5) catalyst exhibited a reduced overpotential of 128 mV and provided a reduced Tafel slope of 57 mV·dec^(−1) to meet the maximum current density of 250 mA·cm^(−2).The optimized strategy for interfacial coupling of the fabricated Cu_(2)Se-V_(2)O_(5) catalyst resulted in a porous structure with accessible active sites,which enabled adsorption of the intermediates and afforded an effective charge transfer rate for promoting the oxygen evolution reaction.Furthermore,the combined effect of the catalyst components provided long-term stability for over 110 h in an alkaline solution,which makes the catalyst promising for large-scale practical applications.The aforementioned advantages of the composite catalyst overcome the limitations of low conductivity,agglomeration,and poor stability of the pure catalysts(Cu2Se and V2O5).
基金support of Khalifa University of Science and Technology under Research Publication Award(Khan)with Project No.8474000195。
文摘This paper presents the development of a novel compliant polymorphing wing capable of chord and camber morphing for small UAVs.The morphing wing can achieve up to 10%chord extension and±20°camber changes.The design,modeling,sizing,manufacturing and mechanical testing of the wing are detailed.The polymorphing wing consists of one continuous front spar fixed to the fuselage and a rear spar on each side of the wing.Each rear spar can translate in the chordwise direction(chord morphing)and rotate around itself(camber morphing).A flexible elastomeric latex sheet is used as the skin to cover the wing and maintain its aerodynamic shape whilst allowing morphing.The loads from the skin are transferred to the spars using the compliant cellular ribs that support the flexible skin and facilitate morphing.Pre-tensioning is applied to the skin to minimize wrinkling when subject to aerodynamic and actuation loads.A rack and pinion actuation system,powered by stepper motors,is used for morphing.Aero-structural design,analysis and sizing are conducted.Performance comparison between the polymorphing wing and the baseline wing(non-morphing)shows that chord morphing improves aerodynamic efficiency at low angles of attack while camber morphing improves efficiency at high angles of attack.
文摘A new feature extraction technique for the detection of lesions created from mucosal inflammations in Crohn's disease, based on wireless capsule endoscopy(WCE) images processing is presented here. More specifically, a novel filtering process, namely Hybrid Adaptive Filtering(HAF), was developed for efficient extraction of lesion-related structural/textural characteristics from WCE images, by employing Genetic Algorithms to the Curvelet-based representation of images. Additionally, Differential Lacunarity(DLac) analysis was applied for feature extraction from the HAF-filtered images. The resulted scheme, namely HAF-DLac, incorporates support vector machines for robust lesion recognition performance. For the training and testing of HAFDLac, an 800-image database was used, acquired from 13 patients who undertook WCE examinations, where the abnormal cases were grouped into mild and severe, according to the severity of the depicted lesion, for a more extensive evaluation of the performance. Experimental results, along with comparison with other related efforts, have shown that the HAF-DLac approach evidently outperforms them in the field of WCE image analysis for automated lesion detection, providing higher classification results, up to 93.8%(accuracy), 95.2%(sensitivity), 92.4%(specificity) and 92.6%(precision). The promising performance of HAF-DLac paves the way for a complete computer-aided diagnosis system that could support physicians' clinical practice.
