Exploration of alternative energy storage systems has been more than necessary in view of the supply risks haunting lithium-ion batteries.Among various alternative electrochemical energy storage devices,sodium-ion bat...Exploration of alternative energy storage systems has been more than necessary in view of the supply risks haunting lithium-ion batteries.Among various alternative electrochemical energy storage devices,sodium-ion battery outstands with advantages of cost-effectiveness and comparable energy density with lithium-ion batteries.Thanks to the similar electrochemical mechanism,the research and development of lithium-ion batteries have forged a solid foundation for sodium-ion battery explorations.Advancements in sodium-ion batteries have been witnessed in terms of superior electrochemical performance and broader application scenarios.Here,the strategies adopted to optimize the battery components(cathode,anode,electrolyte,separator,binder,current collector,etc.)and the cost,safety,and commercialization issues in sodium-ion batteries are summarized and discussed.Based on these optimization strategies,assembly of functional(flexible,stretchable,self-healable,and self-chargeable)and integrated sodium-ion batteries(−actuators,−sensors,electrochromic,etc.)have been realized.Despite these achievements,challenges including energy density,scalability,trade-off between energy density and functionality,cost,etc.are to be addressed for sodium-ion battery commercialization.This review aims at providing an overview of the up-to-date achievements in sodium-ion batteries and serves to inspire more efforts in designing upgraded sodium-ion batteries.展开更多
The next generation of sensors should be self-powered, maintenance-free, precise, and have wide-ranging sensing abilities. Despite extensive research and development in the field of pressure sensors, the sensitivity o...The next generation of sensors should be self-powered, maintenance-free, precise, and have wide-ranging sensing abilities. Despite extensive research and development in the field of pressure sensors, the sensitivity of most pressure sensors declines significantly at higher pressures, such that they are not able to detect a wide range of pressures with a uniformly high sensitivity. In this work, we demonstrate a single-electrode triboelectric pressure sensor, which can detect a wide range of pressures from 0.05 to 600 kPa with a high degree of sensitivity across the entire range by utilizing the synergistic effects of the piezoelectric polarization and triboelectric surface charges of self-polarized polyvinyldifluoride-trifluoroethylene （P（VDF-TrFE）） sponge. Taking into account both this wide pressure range and the sensitivity, this device exhibits the best performance relative to that of previously reported self-powered pressure sensors. This achievement facilitates wide-range pressure detection for a broad spectrum of applications, ranging from simple human touch, sensor networks, smart robotics, and sports applications, thus paving the way forward for the realization of next-generation sensing devices. Moreover, this work addresses the critical issue of saturation pressure in triboelectric nanogenerators and provides insights into the role of the surface charge on a piezoelectric polymer when used in a triboelectric nanogenerator.展开更多
Charging wearable energy storage devices with bioenergy from human-bodymotions, biofluids, and body heat holds great potential to construct self-powered body-worn electronics, especially considering the ceaseless natu...Charging wearable energy storage devices with bioenergy from human-bodymotions, biofluids, and body heat holds great potential to construct self-powered body-worn electronics, especially considering the ceaseless nature ofhuman metabolic activities. To bridge the gap between human-body bioen-ergy and storage of energy, wearable triboelectric/piezoelectric nanogenerators(TENGs/PENGs), biofuel cells (BFCs), thermoelectric generators (TEGs) havebeen designed to harvest energy from body-motions, biofluids, and body heat,respectively. Researchers have explored various strategies using bioenergy har-vesters to charge wearable supercapacitors and batteries to relieve or even fullyeliminate the recharging process from external power stations, thus, makingwearable electronics more sustainable, autonomous, and user friendly. In thisarticle, we review the advances in the design of sustainable energy storagedevices charged by human-body energy harvesters. The progress in multifunc-tional wearable energy storage devices that cater to the easy integration withhuman-body energy harvesters will be summarized. Then, the focus is laid onthe integrating strategies (single-cell strategy and separated-cell strategy), devicedesign, materials selection, and characteristics of different self-charging human-body energy harvesting-storage systems. Finally, the challenges that impedethe wide application of human-body energy harvesters charged supercapaci-tors/batteries and prospects will be discussed both from materials and structuraldesign aspects.展开更多
Over the last 12 years, the Wales Cancer Biobank (WCB) has consented to more than 2000 patients with colorectal cancer (CRC). From these patients, clinical data has been collected and patients have been followed throu...Over the last 12 years, the Wales Cancer Biobank (WCB) has consented to more than 2000 patients with colorectal cancer (CRC). From these patients, clinical data has been collected and patients have been followed through their cancer journey. Clinical data from these patients have been analyzed to identify any correlation between disease grade and outcome. In a small cohort, consisting of 407 patients, WCB has performed genetic analysis on patient primary tumor samples, identifying and characterizing mutations in the KRAS, NRAS, BRAF, PIK3CA and TP53 genes. The majority of patients with CRC who were consented to WCB were male with a mean age of 69 years and received surgery as the primary treatment for their disease. Pathology and disease-free survival data confirmed worse prognoses associated with more advanced disease. Heterogeneity within the primary tumor was explored in a subgroup of patients. Analysis of the KRAS and TP53 genes confirmed that more than 40% of CRC patients who were tested, harbored a genetic mutation within these genes in their primary tumor. Due to the limited sample size tested, most mutations did not show significant differences in disease-free survival, however, mutation of the BRAF gene did show a decrease in the disease specific survival, in keeping with the published data. Analysis of the patients diagnosed with CRC within the Biobank has provided us with valuable information on the status of CRC disease and treatment within the Welsh population. Over 12 years of consenting, we have witnessed significant changes in the information that researchers are interested in when sourcing samples for translational research. The development of new drugs that are tailored to the genetics of a cancer is emerging and at WCB we are focusing our collections on samples and data that meet the needs of this ever-evolving field.展开更多
Pteropine orthoreovirus(PRV)is a nonenveloped double-stranded RNA(dsRNA)virus of the genus Orthoreovirus under the family Reoviridae.The PRV genome is composed of 10 dsRNA segments,including three large(L)segments,thr...Pteropine orthoreovirus(PRV)is a nonenveloped double-stranded RNA(dsRNA)virus of the genus Orthoreovirus under the family Reoviridae.The PRV genome is composed of 10 dsRNA segments,including three large(L)segments,three medium(M)segments,and four small(S)segments surrounded by an icosahedral capsid[1].展开更多
●AIM:To determine the common causes and visual outcome after treatment among uveitis and scleritis patients.●METHODS:This is a retrospective cohort observational study.All consecutive clinical records of patients wi...●AIM:To determine the common causes and visual outcome after treatment among uveitis and scleritis patients.●METHODS:This is a retrospective cohort observational study.All consecutive clinical records of patients with newly diagnosed uveitis and scleritis over a 4-year period,from Jan.1,2017 to Dec.31,2020,were analysed.Data was collected at the presentation and included a follow-up period of one year.●RESULTS:A total of 288 patients were recruited during the study period.Anterior uveitis was the most common anatomical diagnosis(50.0%)followed by panuveitis(25.0%),scleritis(13.5%),posterior uveitis(6.9%),and intermediate uveitis(4.5%).Viral Herpes was the most common cause of infectious cases,while Vogt-Koyanagi-Harada(VKH)disease and human leucocyte antigen(HLA)B27 spondyloarthropathy were the leading causes of identifiable non-infectious cases.Majority of patients presented with unilateral,non-granulomatous uveitis with an absence of hypopyon.Anatomical locations like posterior uveitis and panuveitis,and visual acuity worse than 3/60 at presentation were the factors associated with poor visual outcomes(P<0.05).About 60%of patients had an identifiable cause for the uveitis and scleritis,with nearly equal distribution of infectious(n=85,29.5%)and noninfectious causes(n=84,29.2%).About 14.5%of patients were clinically blind at 1y of follow-up.The most common complication in our uveitis patients was glaucoma(47.5%),followed by cystoid macula oedema(18.9%)and cataract(13.9%).●CONCLUSION:Uveitis and scleritis are important causes of ocular morbidity.They are potentially blinding diseases which can have a good outcome if diagnosed and treated early.展开更多
Though flexible electrochromic devices have shown huge potential application in the fields of safety warning,display and smart windows,limited attention was paid on preparing flexible electrochromic fiber because of t...Though flexible electrochromic devices have shown huge potential application in the fields of safety warning,display and smart windows,limited attention was paid on preparing flexible electrochromic fiber because of the difficulty in fabricating the multilayer electrochromic device structure in one-dimensional form.In this study,a flexible electrochromic nylon fiber based on Ag nanowires(NWs)/PEDOT:PSS/WO3 nanoparticles(NPs)(PEDOT:PSS=poly(3,4-ethylenedioxythiophene):polystyrenesulfonic acid)is successfully fabricated,delivering rapid color switching(2.5 and 9 s for bleaching and coloration)and high optical modulation(65.5%at 633 nm),and sustainable to repeated mechanical deformations.Ag NWs,PEDOT:PSS and WO3 NPs were dip-coated on the nylon fiber,resulting in an electrochromic fiber electrode with stable fiber resistance of 50-100Ω/10 cm,which can withstand mechanical deformation against 300 times of bending cycles with bending radius of 0.5 cm,and sustain 30 times of tape-peeling.During the galvanostatic tests,the capacitance of the electrochromic electrode can maintain 70%of the initial value even after 5,000 times of charge-discharge cycles.Even in knotted shape,the fiber still shows excellent color contrast.This study provides a novel method to construct flexible electrochromic fiber and pave the way for the development of flexible optoelectronic devices,such as flexible and wearable displays.展开更多
Pteropine orthoreovirus(PRV)is an emerging zoonotic respiratory virus with the potential to spill over from fruit bats to humans.PRV belongs to the family Reoviridae,whose name is derived from an abbreviation of"...Pteropine orthoreovirus(PRV)is an emerging zoonotic respiratory virus with the potential to spill over from fruit bats to humans.PRV belongs to the family Reoviridae,whose name is derived from an abbreviation of"respiratory enteric orphan".This family of viruses was initially not believed to cause diseases in humans and therefore was named an"orphan virus".PRV infections in humans are characterized by symptoms ranging from mild influenza-like illness to severe acute respiratory distress.展开更多
Sodium-ion capacitors(SICs)have received increasing interest for grid stationary energy storage application due to their affordability,high power,and energy densities.The major challenge for SICs is to overcome the ki...Sodium-ion capacitors(SICs)have received increasing interest for grid stationary energy storage application due to their affordability,high power,and energy densities.The major challenge for SICs is to overcome the kinetics imbalance between faradaic anode and nonfaradaic cathode.To boost the Na+reaction kinetics,the present work demonstrated a high-rate MnS-based anode by embedding the MnS nanocrystals into the N,S-co-doped carbon matrix(MnS@NSC).Benefiting from the fast pseudocapacitive Na+storage behavior,the resulting composite exhibits extraordinary rate capability(205.6 mAh g−1 at 10 A g−1)and outstanding cycling stability without notable degradation after 2000 cycles.A prototype SIC was demonstrated using MnS@NSC anode and N-doped porous carbon(NC)cathode;the obtained hybrid SIC device can display a high energy density of 139.8 Wh kg−1 and high power density of 11,500 W kg−1,as well as excellent cyclability with 84.5%capacitance retention after 3000 cycles.The superior electrochemical performance is contributed to downsizing of MnS and encapsulation of conductive N,S-co-doped carbon matrix,which not only promote the Na+and electrons transport,but also buffer the volume variations and maintain the structure integrity during Na+insertion/extraction,enabling its comparable fast reaction kinetics and cyclability with NC cathode.展开更多
Flexible thin-film transistors(TFTs)have attracted wide interest in the development of flexible and wearable displays or sensors.However,the conventional high processing temperatures hinder the preparation of stable a...Flexible thin-film transistors(TFTs)have attracted wide interest in the development of flexible and wearable displays or sensors.However,the conventional high processing temperatures hinder the preparation of stable and reliable dielectric materials on flexible substrates.Here,we develop a stable laminated Al_(2)O_(3)/HfO_(2) insulator by atomic layer deposition at a relatively lower temperature of 150℃.A sputtered amorphous indium-gallium-zinc oxide(IGZO)with the stoichiometry of In_(0.37)Ga_(0.20)Zn_(0.18)O_(0.25) is used as the active channel material.The flexible TFTs with bottom-gate top-contacted configuration are further fabricated on a flexible polyimide substrate with the Al_(2)O_(3)/HfO_(2) nanolaminates.Benefited from the unique structural and compositional configuration in the nanolaminates consisting of amorphous Al_(2)O_(3),crystallized HfO_(2),and the aluminate Al-Hf-O phase,the as-prepared TFTs present the carrier mobilities of 9.7 cm^(2) V^(−1) s^(−1),ON/OFF ratio of-1.3×10^(6),subthreshold voltage of 0.1 V,saturated current up to 0.83 mA,and subthreshold swing of 0.256 V dec^(−1),signifying a high-performance flexible TFT,which simultaneously able to withstand the bending radius of 40 mm.The TFTs with nanolaminate insulator possess satisfactory humidity stability and hysteresis behavior in a relative humidity of 60-70%,a temperature of 25-30℃ environment.The yield of IGZO-based TFTs with the nanolaminate insulator reaches 95%.展开更多
Living in a world of heavy industrialization and confronted by the ever-deteriorating environment,the human race is now undertaking serious efforts to reach the target of carbon neutrality.One major step is to promote...Living in a world of heavy industrialization and confronted by the ever-deteriorating environment,the human race is now undertaking serious efforts to reach the target of carbon neutrality.One major step is to promote the development of sustainable electrochemical energy storage and conversion technologies based on green resources instead of the traditional nonreusable petroleum-based technologies.As an almost inexhaustible bioresource,nanocellulose derived from natural biomass exhibits outstanding physiochemical properties that could be well leveraged to bring about numerous opportunities for electrochemical processes.Through structure engineering,nanocellulose with a width of a few tens of nanometers and a length of up to micrometers could be realized.The drastic reduction in dimensions leads to superior mechanical,optical,and functional properties inaccessible to the bulky cellulose counterpart.In this review,different types of nanocellulose with distinctive physiochemical properties and their respective preparation methods are first examined.This is followed by a detailed and insightful analysis of the superiority and unprecedented performance gains that nanocellulose imparts to different electrochemical energy storage and conversion applications as a result of nanosizing.Finally,we humbly put forward our perspectives on the problems regarding current studies as well as on the future research direction for nanocellulose-mediated electrochemical processes to enable practical applications.This review is intended as guidance to initiate cross-disciplinary research effort in this engaging field and help evoke inspiration to effect solutions to critical energy issues of the day.展开更多
This case report aims to report an uncommon case of bee sting keratopathy with retained stinger.A 55-year-old man presented with left cornea bee sting while gardening two days prior to first visit.He complained of sev...This case report aims to report an uncommon case of bee sting keratopathy with retained stinger.A 55-year-old man presented with left cornea bee sting while gardening two days prior to first visit.He complained of severe eye pain with redness,tearing and blurring of vision.On examination,his right eye visual acuity was 6/6 and in left eye was hand movement.There was generalized conjunctival hyperemia and cornea showing significant descemet striae.A bee stinger with surrounding infiltration noted at 2 o'clock was associated with striate keratitis.It was deeply seated at the posterior third of cornea stroma near to paracentral area.Pupil was mid-dilated with absence of relative afferent pupillary defect.There was neither hypopyon nor cataract.The posterior segment could not be visualized due to severe corneal edema.However,B-scan ultrasound was normal.Bee stinger was removed under local anaesthesia on the day of presentation.Post-operatively,patient was administered with topical moxifloxacin and topical non steroidal anti-inflammatory drugs.Three weeks later,there was resolution of cornea infiltrate with improvement of striate keratitis and his vision was improved to 1/60.However,cornea edema did not regress but ended up with bullous keratopathy.The patient has undergone descemet-stripping automated endothelial keratoplasty and his vision was improved to 6/9.We recommend early stinger removal to reduce the possible sequelae of bee sting toxicity for better visual outcome.展开更多
Uveitis secondary to Vogt-Koyanagi-Harada disease is rare in children.To the best of our knowledge,this patient is the first reported case of uveitis attributed to VKH in a child in Malaysia.A 9-year-old girl complain...Uveitis secondary to Vogt-Koyanagi-Harada disease is rare in children.To the best of our knowledge,this patient is the first reported case of uveitis attributed to VKH in a child in Malaysia.A 9-year-old girl complained of non-resolving painful red eyes bilaterally for 3 months.Anterior segment of right eye showed mutton fat keratic precipitates,posterior synechiae and moderate anterior chamber reaction.Anterior segment of left eye revealed mutton fat keratic precipitates,band keratopathy on peripheral 3 and 9 o'clock of the cornea,iris bombe,iris nodule and seclusio pupillae.Fundus examination of right eye revealed subretinal deposit at superior and inferior arcades with flat retina while left eye showed hazy view.Patient was then noted to have poliosis and vitiligo after 1 month from initial presentation.Mild cataract and widespread atrophy of the retinal pigment epithelium accounting for the loss in vision remained.This case report is to highlight the importance of early recognition of paediatric Vogt-Koyanagi-Harada and treating it aggressively to prevent the irreversible destructive sequalae of the disease.展开更多
A 52 year-old construction worker presented with progressive painful blurring of vision in the left eye associated with redness for past 1 month.There was a history of penetrating injury in the same eye 10 years ago a...A 52 year-old construction worker presented with progressive painful blurring of vision in the left eye associated with redness for past 1 month.There was a history of penetrating injury in the same eye 10 years ago and he underwent primary wound toilet and suturing,lens removal with intraocular lens implantation.Slit lamp examination revealed a corneal scar at 9’oclock,a large transilluminant iris cyst superotemporally and adherent to corneal endothelium.It was extended from angle of the pupil and obstructing the visual axis.The patient underwent excision of an iris cyst through superior limbal incision.Viscodissection was done to separate the cyst from the corneal endothelium and underlying iris stroma.Trypan blue ophthalmic solution was injected into the cyst to stain the cyst capsule.Post operatively 7 days,vision improved to 6/7.5 without complication.There was no recurrence up to 1 year postoperation.Histopathological finding revealed a benign cyst mass lined by simple cuboidal to nonkeratinized stratified squamous epithelium.We had achieved a good surgical outcome with no complication to date for our case study.We advocate this modified surgical method to completely remove iris cyst.展开更多
In this paper,we review our joint timing and frequency synchronization algorithms in coherent optical orthogonal frequency division multiplexing(CO-OFDM)systems.We first present a timing estimation method by designing...In this paper,we review our joint timing and frequency synchronization algorithms in coherent optical orthogonal frequency division multiplexing(CO-OFDM)systems.We first present a timing estimation method by designing the pattern of the training symbol,whose timing metric has a sharp and clear peak,to ensure accurate timing offset(TO)estimation performance.Then we provide both data-aided(DA)and blind(BL)approaches to estimate the carrier frequency offset(CFO).For the DA algorithm,we utilize the same training symbol structure as the timing estimation does,while for the BL algorithm,we utilize the zero-subcarrier power(ZSP)to achieve full-range CFO estimation.Note that our joint timing and frequency synchronization approaches require only one OFDM symbol,which ensure not only the data transmission efficiency,but also the TO and CFO estimation performance.A modified BL ZSP algorithm is proposed to further improve the CFO estimation performance by taking the power average over a series of OFDM symbols.The effectiveness of the TO estimation algorithm,and both the DA and BL CFO estimation algorithms are verified and demonstrated in both simulations and experiments.展开更多
With the mindset of constant improvement in efficiency and safety in the workspace and training in Singapore,there is a need to explore varying technologies and their capabilities to fulfil this need.The ability of Vi...With the mindset of constant improvement in efficiency and safety in the workspace and training in Singapore,there is a need to explore varying technologies and their capabilities to fulfil this need.The ability of Virtual Reality(VR)and Augmented Reality(AR)to create an immersive experience of tying the virtual and physical environments coupled with information filtering capabilities brings a possibility of introducing this technology into the training process and workspace.This paper surveys current research trends,findings and limitation of VR and AR in its effect on human performance,specifically in Singapore,and our experience in the National University of Singapore(NUS).展开更多
Objective:To systematically map the stepwise events leading to deoxyelephantopin-induced cell death of HCT116 human colorectal cancer cells and evaluate the effectiveness of deoxyelephantopin in vivo.Methods:HCT116 ce...Objective:To systematically map the stepwise events leading to deoxyelephantopin-induced cell death of HCT116 human colorectal cancer cells and evaluate the effectiveness of deoxyelephantopin in vivo.Methods:HCT116 cells were treated with deoxyelephantopin at various concentrations and time points.Autophagy was confirmed by the detection of autophagosomes and autophagosomal proteins by electron microscopy and Western blotting assays,respectively,and then validated by siRNA knockdown.In addition,apoptosis was confirmed by the detection of apoptosis-related proteins.The intracellular reactive oxygen species(ROS)level was measured using flow cytometry.The growth inhibitory effect of deoxyelephantopin was further evaluated in vivo using a mouse xenograft model.Results:Deoxyelephantopin firstly elevated ROS production,which then triggered autophagic flux with the accumulation of autophagosomal proteins including LC3 A/B,ATG5,and ATG7,followed by the induction of apoptosis via the intrinsic and extrinsic pathways.Pre-treatment with N-acetyl-L-cysteine,a ROS inhibitor,reversed both apoptosis and autophagy.The knockdown of LC3 prevented apoptosis induction which confirmed that deoxyelephantopin induced autophagy-dependent apoptosis in HCT116 cells.Accumulation of ROS also activated apoptosis via the mitogen-activated protein kinases signaling pathway.Furthermore,deoxyelephantopin also inhibited the PI3 K/AKT/mTOR pathway,which then released the inhibition of autophagy.In vivo study further showed that deoxyelephantopin significantly suppressed the growth of HCT116 subcutaneous xenograft in nude mice.Conclusions:Our findings revealed that deoxyelephantopin elevates oxidative stress and induces ROS-dependent autophagy followed by apoptosis in HCT116 cells via the concerted modulation of multiple signaling pathways.These findings further support the development of deoxyelephantopin as a therapeutic agent for colorectal cancer.展开更多
Objective:To investigate the involvement of Ca^(2+)in dengue virus(DENV)-infected human umbilical vein endothelial cells(HUVECs)and the disruption of endothelial integrity.Methods:HUVECs were infected with DENV-2 in t...Objective:To investigate the involvement of Ca^(2+)in dengue virus(DENV)-infected human umbilical vein endothelial cells(HUVECs)and the disruption of endothelial integrity.Methods:HUVECs were infected with DENV-2 in the presence of intracellular Ca^(2+)or endoplasmic reticulum Ca^(2+)chelators.Virus infectivity was measured by focus-forming assay and quantitative RT-PCR.Intracellular Ca^(2+)was measured using Fluo-4-AM dye.VE-cadherin and focal adhesion kinase(FAK)expressions were investigated by immunofluorescence and immunoblotting assays,respectively.Results:DENV infection increased intracellular cytosolic Ca^(2+)levels and caused disassembly of the adherens junction protein,VEcadherin as evidenced by decreased VE-cadherin expression at the periphery of DENV-2 infected HUVECs.Depletion of intracellular Ca^(2+)stores,particularly those of the endoplasmic reticulum Ca^(2+),significantly decreased DENV yield in HUVECs.Decreased virus yield following the depletion of intracellular Ca^(2+)was caused by the inhibition of viral entry into HUVECs and not the inhibition of viral binding or attachment.DENV-2 infection also resulted in Ca^(2+)-dependent activation of FAK.Conclusions:Intracellular Ca^(2+)is required for the early phases of DENV infection in endothelial cells.Increased cytosolic Ca^(2+)levels in endothelial cells during DENV infection activated FAK,disrupted adherens junctions and compromised barrier integrity.Thus,Ca^(2+)plays an important role in DENV infection in endothelial cells.展开更多
基金supported by the National Natural Science Foundation of China(No.52202320)the Fundamental Research Funds for the Central Universities(No.862201013153)+2 种基金the Shandong Excel ent Young Scientists Fund Program(Overseas)(2023HWYQ-060)the Ministry of Education Ac RF Tier 1 Award RT15/20,SingaporeD.H.C.C.acknowledges the funding support from NUS R284000-227-114
文摘Exploration of alternative energy storage systems has been more than necessary in view of the supply risks haunting lithium-ion batteries.Among various alternative electrochemical energy storage devices,sodium-ion battery outstands with advantages of cost-effectiveness and comparable energy density with lithium-ion batteries.Thanks to the similar electrochemical mechanism,the research and development of lithium-ion batteries have forged a solid foundation for sodium-ion battery explorations.Advancements in sodium-ion batteries have been witnessed in terms of superior electrochemical performance and broader application scenarios.Here,the strategies adopted to optimize the battery components(cathode,anode,electrolyte,separator,binder,current collector,etc.)and the cost,safety,and commercialization issues in sodium-ion batteries are summarized and discussed.Based on these optimization strategies,assembly of functional(flexible,stretchable,self-healable,and self-chargeable)and integrated sodium-ion batteries(−actuators,−sensors,electrochromic,etc.)have been realized.Despite these achievements,challenges including energy density,scalability,trade-off between energy density and functionality,cost,etc.are to be addressed for sodium-ion battery commercialization.This review aims at providing an overview of the up-to-date achievements in sodium-ion batteries and serves to inspire more efforts in designing upgraded sodium-ion batteries.
文摘The next generation of sensors should be self-powered, maintenance-free, precise, and have wide-ranging sensing abilities. Despite extensive research and development in the field of pressure sensors, the sensitivity of most pressure sensors declines significantly at higher pressures, such that they are not able to detect a wide range of pressures with a uniformly high sensitivity. In this work, we demonstrate a single-electrode triboelectric pressure sensor, which can detect a wide range of pressures from 0.05 to 600 kPa with a high degree of sensitivity across the entire range by utilizing the synergistic effects of the piezoelectric polarization and triboelectric surface charges of self-polarized polyvinyldifluoride-trifluoroethylene （P（VDF-TrFE）） sponge. Taking into account both this wide pressure range and the sensitivity, this device exhibits the best performance relative to that of previously reported self-powered pressure sensors. This achievement facilitates wide-range pressure detection for a broad spectrum of applications, ranging from simple human touch, sensor networks, smart robotics, and sports applications, thus paving the way forward for the realization of next-generation sensing devices. Moreover, this work addresses the critical issue of saturation pressure in triboelectric nanogenerators and provides insights into the role of the surface charge on a piezoelectric polymer when used in a triboelectric nanogenerator.
文摘Charging wearable energy storage devices with bioenergy from human-bodymotions, biofluids, and body heat holds great potential to construct self-powered body-worn electronics, especially considering the ceaseless nature ofhuman metabolic activities. To bridge the gap between human-body bioen-ergy and storage of energy, wearable triboelectric/piezoelectric nanogenerators(TENGs/PENGs), biofuel cells (BFCs), thermoelectric generators (TEGs) havebeen designed to harvest energy from body-motions, biofluids, and body heat,respectively. Researchers have explored various strategies using bioenergy har-vesters to charge wearable supercapacitors and batteries to relieve or even fullyeliminate the recharging process from external power stations, thus, makingwearable electronics more sustainable, autonomous, and user friendly. In thisarticle, we review the advances in the design of sustainable energy storagedevices charged by human-body energy harvesters. The progress in multifunc-tional wearable energy storage devices that cater to the easy integration withhuman-body energy harvesters will be summarized. Then, the focus is laid onthe integrating strategies (single-cell strategy and separated-cell strategy), devicedesign, materials selection, and characteristics of different self-charging human-body energy harvesting-storage systems. Finally, the challenges that impedethe wide application of human-body energy harvesters charged supercapaci-tors/batteries and prospects will be discussed both from materials and structuraldesign aspects.
文摘Over the last 12 years, the Wales Cancer Biobank (WCB) has consented to more than 2000 patients with colorectal cancer (CRC). From these patients, clinical data has been collected and patients have been followed through their cancer journey. Clinical data from these patients have been analyzed to identify any correlation between disease grade and outcome. In a small cohort, consisting of 407 patients, WCB has performed genetic analysis on patient primary tumor samples, identifying and characterizing mutations in the KRAS, NRAS, BRAF, PIK3CA and TP53 genes. The majority of patients with CRC who were consented to WCB were male with a mean age of 69 years and received surgery as the primary treatment for their disease. Pathology and disease-free survival data confirmed worse prognoses associated with more advanced disease. Heterogeneity within the primary tumor was explored in a subgroup of patients. Analysis of the KRAS and TP53 genes confirmed that more than 40% of CRC patients who were tested, harbored a genetic mutation within these genes in their primary tumor. Due to the limited sample size tested, most mutations did not show significant differences in disease-free survival, however, mutation of the BRAF gene did show a decrease in the disease specific survival, in keeping with the published data. Analysis of the patients diagnosed with CRC within the Biobank has provided us with valuable information on the status of CRC disease and treatment within the Welsh population. Over 12 years of consenting, we have witnessed significant changes in the information that researchers are interested in when sourcing samples for translational research. The development of new drugs that are tailored to the genetics of a cancer is emerging and at WCB we are focusing our collections on samples and data that meet the needs of this ever-evolving field.
基金supported by the Fundamental Research Grant Scheme (FRGS)2019-1 (FRGS/1/2019/STG05/IMU/02/1)from the Ministry of Higher Education,Malaysia,International Medical University Research Grant (BP I-01-2018 (33))Pump priming Grant (F0013.54.04)University of Nottingham Malaysia。
文摘Pteropine orthoreovirus(PRV)is a nonenveloped double-stranded RNA(dsRNA)virus of the genus Orthoreovirus under the family Reoviridae.The PRV genome is composed of 10 dsRNA segments,including three large(L)segments,three medium(M)segments,and four small(S)segments surrounded by an icosahedral capsid[1].
文摘●AIM:To determine the common causes and visual outcome after treatment among uveitis and scleritis patients.●METHODS:This is a retrospective cohort observational study.All consecutive clinical records of patients with newly diagnosed uveitis and scleritis over a 4-year period,from Jan.1,2017 to Dec.31,2020,were analysed.Data was collected at the presentation and included a follow-up period of one year.●RESULTS:A total of 288 patients were recruited during the study period.Anterior uveitis was the most common anatomical diagnosis(50.0%)followed by panuveitis(25.0%),scleritis(13.5%),posterior uveitis(6.9%),and intermediate uveitis(4.5%).Viral Herpes was the most common cause of infectious cases,while Vogt-Koyanagi-Harada(VKH)disease and human leucocyte antigen(HLA)B27 spondyloarthropathy were the leading causes of identifiable non-infectious cases.Majority of patients presented with unilateral,non-granulomatous uveitis with an absence of hypopyon.Anatomical locations like posterior uveitis and panuveitis,and visual acuity worse than 3/60 at presentation were the factors associated with poor visual outcomes(P<0.05).About 60%of patients had an identifiable cause for the uveitis and scleritis,with nearly equal distribution of infectious(n=85,29.5%)and noninfectious causes(n=84,29.2%).About 14.5%of patients were clinically blind at 1y of follow-up.The most common complication in our uveitis patients was glaucoma(47.5%),followed by cystoid macula oedema(18.9%)and cataract(13.9%).●CONCLUSION:Uveitis and scleritis are important causes of ocular morbidity.They are potentially blinding diseases which can have a good outcome if diagnosed and treated early.
基金supported by National Research Foundation Investigatorship(No.NRF-NRFI201605)。
文摘Though flexible electrochromic devices have shown huge potential application in the fields of safety warning,display and smart windows,limited attention was paid on preparing flexible electrochromic fiber because of the difficulty in fabricating the multilayer electrochromic device structure in one-dimensional form.In this study,a flexible electrochromic nylon fiber based on Ag nanowires(NWs)/PEDOT:PSS/WO3 nanoparticles(NPs)(PEDOT:PSS=poly(3,4-ethylenedioxythiophene):polystyrenesulfonic acid)is successfully fabricated,delivering rapid color switching(2.5 and 9 s for bleaching and coloration)and high optical modulation(65.5%at 633 nm),and sustainable to repeated mechanical deformations.Ag NWs,PEDOT:PSS and WO3 NPs were dip-coated on the nylon fiber,resulting in an electrochromic fiber electrode with stable fiber resistance of 50-100Ω/10 cm,which can withstand mechanical deformation against 300 times of bending cycles with bending radius of 0.5 cm,and sustain 30 times of tape-peeling.During the galvanostatic tests,the capacitance of the electrochromic electrode can maintain 70%of the initial value even after 5,000 times of charge-discharge cycles.Even in knotted shape,the fiber still shows excellent color contrast.This study provides a novel method to construct flexible electrochromic fiber and pave the way for the development of flexible optoelectronic devices,such as flexible and wearable displays.
基金This study was supported by International Medical University grants BMSI-2012(03)and BMSI-2018(04).
文摘Pteropine orthoreovirus(PRV)is an emerging zoonotic respiratory virus with the potential to spill over from fruit bats to humans.PRV belongs to the family Reoviridae,whose name is derived from an abbreviation of"respiratory enteric orphan".This family of viruses was initially not believed to cause diseases in humans and therefore was named an"orphan virus".PRV infections in humans are characterized by symptoms ranging from mild influenza-like illness to severe acute respiratory distress.
基金financially supported by the NRF Investigatorship (NRFI), Award No. NRF-NRFI2016-05the Campus for Research Excellent and Technological Enterprise (CREATE),National Research Foundation, Prime Minister’s Office, Singapore
文摘Sodium-ion capacitors(SICs)have received increasing interest for grid stationary energy storage application due to their affordability,high power,and energy densities.The major challenge for SICs is to overcome the kinetics imbalance between faradaic anode and nonfaradaic cathode.To boost the Na+reaction kinetics,the present work demonstrated a high-rate MnS-based anode by embedding the MnS nanocrystals into the N,S-co-doped carbon matrix(MnS@NSC).Benefiting from the fast pseudocapacitive Na+storage behavior,the resulting composite exhibits extraordinary rate capability(205.6 mAh g−1 at 10 A g−1)and outstanding cycling stability without notable degradation after 2000 cycles.A prototype SIC was demonstrated using MnS@NSC anode and N-doped porous carbon(NC)cathode;the obtained hybrid SIC device can display a high energy density of 139.8 Wh kg−1 and high power density of 11,500 W kg−1,as well as excellent cyclability with 84.5%capacitance retention after 3000 cycles.The superior electrochemical performance is contributed to downsizing of MnS and encapsulation of conductive N,S-co-doped carbon matrix,which not only promote the Na+and electrons transport,but also buffer the volume variations and maintain the structure integrity during Na+insertion/extraction,enabling its comparable fast reaction kinetics and cyclability with NC cathode.
基金This work was supported by the Competitive Research Program(Award No.NRF-CRP13-2014-02),RIE2020 ASTAR AME IAF-ICP(I1801E0030)Campus for Research Excellence and Technological Enterprise(CREATE)that was supported by the National Research Foundation,Prime Minister’s Office,Singapore+1 种基金Q.W.S.thanks to the Natural Science Foundation of China(52003122)the"Longshan scholar"start-up foundation of NUIST.
文摘Flexible thin-film transistors(TFTs)have attracted wide interest in the development of flexible and wearable displays or sensors.However,the conventional high processing temperatures hinder the preparation of stable and reliable dielectric materials on flexible substrates.Here,we develop a stable laminated Al_(2)O_(3)/HfO_(2) insulator by atomic layer deposition at a relatively lower temperature of 150℃.A sputtered amorphous indium-gallium-zinc oxide(IGZO)with the stoichiometry of In_(0.37)Ga_(0.20)Zn_(0.18)O_(0.25) is used as the active channel material.The flexible TFTs with bottom-gate top-contacted configuration are further fabricated on a flexible polyimide substrate with the Al_(2)O_(3)/HfO_(2) nanolaminates.Benefited from the unique structural and compositional configuration in the nanolaminates consisting of amorphous Al_(2)O_(3),crystallized HfO_(2),and the aluminate Al-Hf-O phase,the as-prepared TFTs present the carrier mobilities of 9.7 cm^(2) V^(−1) s^(−1),ON/OFF ratio of-1.3×10^(6),subthreshold voltage of 0.1 V,saturated current up to 0.83 mA,and subthreshold swing of 0.256 V dec^(−1),signifying a high-performance flexible TFT,which simultaneously able to withstand the bending radius of 40 mm.The TFTs with nanolaminate insulator possess satisfactory humidity stability and hysteresis behavior in a relative humidity of 60-70%,a temperature of 25-30℃ environment.The yield of IGZO-based TFTs with the nanolaminate insulator reaches 95%.
基金supported by the National Natural Science Foundation of China(Nos.51933007,51673123,51803141)National Key R&D Program of China(No.2017YFE0111500).
文摘Living in a world of heavy industrialization and confronted by the ever-deteriorating environment,the human race is now undertaking serious efforts to reach the target of carbon neutrality.One major step is to promote the development of sustainable electrochemical energy storage and conversion technologies based on green resources instead of the traditional nonreusable petroleum-based technologies.As an almost inexhaustible bioresource,nanocellulose derived from natural biomass exhibits outstanding physiochemical properties that could be well leveraged to bring about numerous opportunities for electrochemical processes.Through structure engineering,nanocellulose with a width of a few tens of nanometers and a length of up to micrometers could be realized.The drastic reduction in dimensions leads to superior mechanical,optical,and functional properties inaccessible to the bulky cellulose counterpart.In this review,different types of nanocellulose with distinctive physiochemical properties and their respective preparation methods are first examined.This is followed by a detailed and insightful analysis of the superiority and unprecedented performance gains that nanocellulose imparts to different electrochemical energy storage and conversion applications as a result of nanosizing.Finally,we humbly put forward our perspectives on the problems regarding current studies as well as on the future research direction for nanocellulose-mediated electrochemical processes to enable practical applications.This review is intended as guidance to initiate cross-disciplinary research effort in this engaging field and help evoke inspiration to effect solutions to critical energy issues of the day.
文摘This case report aims to report an uncommon case of bee sting keratopathy with retained stinger.A 55-year-old man presented with left cornea bee sting while gardening two days prior to first visit.He complained of severe eye pain with redness,tearing and blurring of vision.On examination,his right eye visual acuity was 6/6 and in left eye was hand movement.There was generalized conjunctival hyperemia and cornea showing significant descemet striae.A bee stinger with surrounding infiltration noted at 2 o'clock was associated with striate keratitis.It was deeply seated at the posterior third of cornea stroma near to paracentral area.Pupil was mid-dilated with absence of relative afferent pupillary defect.There was neither hypopyon nor cataract.The posterior segment could not be visualized due to severe corneal edema.However,B-scan ultrasound was normal.Bee stinger was removed under local anaesthesia on the day of presentation.Post-operatively,patient was administered with topical moxifloxacin and topical non steroidal anti-inflammatory drugs.Three weeks later,there was resolution of cornea infiltrate with improvement of striate keratitis and his vision was improved to 1/60.However,cornea edema did not regress but ended up with bullous keratopathy.The patient has undergone descemet-stripping automated endothelial keratoplasty and his vision was improved to 6/9.We recommend early stinger removal to reduce the possible sequelae of bee sting toxicity for better visual outcome.
文摘Uveitis secondary to Vogt-Koyanagi-Harada disease is rare in children.To the best of our knowledge,this patient is the first reported case of uveitis attributed to VKH in a child in Malaysia.A 9-year-old girl complained of non-resolving painful red eyes bilaterally for 3 months.Anterior segment of right eye showed mutton fat keratic precipitates,posterior synechiae and moderate anterior chamber reaction.Anterior segment of left eye revealed mutton fat keratic precipitates,band keratopathy on peripheral 3 and 9 o'clock of the cornea,iris bombe,iris nodule and seclusio pupillae.Fundus examination of right eye revealed subretinal deposit at superior and inferior arcades with flat retina while left eye showed hazy view.Patient was then noted to have poliosis and vitiligo after 1 month from initial presentation.Mild cataract and widespread atrophy of the retinal pigment epithelium accounting for the loss in vision remained.This case report is to highlight the importance of early recognition of paediatric Vogt-Koyanagi-Harada and treating it aggressively to prevent the irreversible destructive sequalae of the disease.
文摘A 52 year-old construction worker presented with progressive painful blurring of vision in the left eye associated with redness for past 1 month.There was a history of penetrating injury in the same eye 10 years ago and he underwent primary wound toilet and suturing,lens removal with intraocular lens implantation.Slit lamp examination revealed a corneal scar at 9’oclock,a large transilluminant iris cyst superotemporally and adherent to corneal endothelium.It was extended from angle of the pupil and obstructing the visual axis.The patient underwent excision of an iris cyst through superior limbal incision.Viscodissection was done to separate the cyst from the corneal endothelium and underlying iris stroma.Trypan blue ophthalmic solution was injected into the cyst to stain the cyst capsule.Post operatively 7 days,vision improved to 6/7.5 without complication.There was no recurrence up to 1 year postoperation.Histopathological finding revealed a benign cyst mass lined by simple cuboidal to nonkeratinized stratified squamous epithelium.We had achieved a good surgical outcome with no complication to date for our case study.We advocate this modified surgical method to completely remove iris cyst.
文摘In this paper,we review our joint timing and frequency synchronization algorithms in coherent optical orthogonal frequency division multiplexing(CO-OFDM)systems.We first present a timing estimation method by designing the pattern of the training symbol,whose timing metric has a sharp and clear peak,to ensure accurate timing offset(TO)estimation performance.Then we provide both data-aided(DA)and blind(BL)approaches to estimate the carrier frequency offset(CFO).For the DA algorithm,we utilize the same training symbol structure as the timing estimation does,while for the BL algorithm,we utilize the zero-subcarrier power(ZSP)to achieve full-range CFO estimation.Note that our joint timing and frequency synchronization approaches require only one OFDM symbol,which ensure not only the data transmission efficiency,but also the TO and CFO estimation performance.A modified BL ZSP algorithm is proposed to further improve the CFO estimation performance by taking the power average over a series of OFDM symbols.The effectiveness of the TO estimation algorithm,and both the DA and BL CFO estimation algorithms are verified and demonstrated in both simulations and experiments.
文摘With the mindset of constant improvement in efficiency and safety in the workspace and training in Singapore,there is a need to explore varying technologies and their capabilities to fulfil this need.The ability of Virtual Reality(VR)and Augmented Reality(AR)to create an immersive experience of tying the virtual and physical environments coupled with information filtering capabilities brings a possibility of introducing this technology into the training process and workspace.This paper surveys current research trends,findings and limitation of VR and AR in its effect on human performance,specifically in Singapore,and our experience in the National University of Singapore(NUS).
文摘Objective:To systematically map the stepwise events leading to deoxyelephantopin-induced cell death of HCT116 human colorectal cancer cells and evaluate the effectiveness of deoxyelephantopin in vivo.Methods:HCT116 cells were treated with deoxyelephantopin at various concentrations and time points.Autophagy was confirmed by the detection of autophagosomes and autophagosomal proteins by electron microscopy and Western blotting assays,respectively,and then validated by siRNA knockdown.In addition,apoptosis was confirmed by the detection of apoptosis-related proteins.The intracellular reactive oxygen species(ROS)level was measured using flow cytometry.The growth inhibitory effect of deoxyelephantopin was further evaluated in vivo using a mouse xenograft model.Results:Deoxyelephantopin firstly elevated ROS production,which then triggered autophagic flux with the accumulation of autophagosomal proteins including LC3 A/B,ATG5,and ATG7,followed by the induction of apoptosis via the intrinsic and extrinsic pathways.Pre-treatment with N-acetyl-L-cysteine,a ROS inhibitor,reversed both apoptosis and autophagy.The knockdown of LC3 prevented apoptosis induction which confirmed that deoxyelephantopin induced autophagy-dependent apoptosis in HCT116 cells.Accumulation of ROS also activated apoptosis via the mitogen-activated protein kinases signaling pathway.Furthermore,deoxyelephantopin also inhibited the PI3 K/AKT/mTOR pathway,which then released the inhibition of autophagy.In vivo study further showed that deoxyelephantopin significantly suppressed the growth of HCT116 subcutaneous xenograft in nude mice.Conclusions:Our findings revealed that deoxyelephantopin elevates oxidative stress and induces ROS-dependent autophagy followed by apoptosis in HCT116 cells via the concerted modulation of multiple signaling pathways.These findings further support the development of deoxyelephantopin as a therapeutic agent for colorectal cancer.
基金funding from the Ministry of Higher Education Malaysia via the Higher Institution Centre of Excellence(HICo E)program(MO002-2019)Development of Research Institute for Excellent Enterprises(ATC+)Project,Republic of Korea(IF001-2021)
文摘Objective:To investigate the involvement of Ca^(2+)in dengue virus(DENV)-infected human umbilical vein endothelial cells(HUVECs)and the disruption of endothelial integrity.Methods:HUVECs were infected with DENV-2 in the presence of intracellular Ca^(2+)or endoplasmic reticulum Ca^(2+)chelators.Virus infectivity was measured by focus-forming assay and quantitative RT-PCR.Intracellular Ca^(2+)was measured using Fluo-4-AM dye.VE-cadherin and focal adhesion kinase(FAK)expressions were investigated by immunofluorescence and immunoblotting assays,respectively.Results:DENV infection increased intracellular cytosolic Ca^(2+)levels and caused disassembly of the adherens junction protein,VEcadherin as evidenced by decreased VE-cadherin expression at the periphery of DENV-2 infected HUVECs.Depletion of intracellular Ca^(2+)stores,particularly those of the endoplasmic reticulum Ca^(2+),significantly decreased DENV yield in HUVECs.Decreased virus yield following the depletion of intracellular Ca^(2+)was caused by the inhibition of viral entry into HUVECs and not the inhibition of viral binding or attachment.DENV-2 infection also resulted in Ca^(2+)-dependent activation of FAK.Conclusions:Intracellular Ca^(2+)is required for the early phases of DENV infection in endothelial cells.Increased cytosolic Ca^(2+)levels in endothelial cells during DENV infection activated FAK,disrupted adherens junctions and compromised barrier integrity.Thus,Ca^(2+)plays an important role in DENV infection in endothelial cells.
