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1.
Proc Natl Acad Sci U S A ; 119(5)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35078938

RESUMO

Viruses are a distinct type of replicators that encode structural proteins encasing virus genomes in virions. For some of the widespread virus capsid proteins and other major components of virions, likely ancestors encoded by cellular life forms are identifiable. In particular, one of the most common capsid proteins, with the single jelly-roll (SJR) fold, appears to have evolved from a particular family of cellular carbohydrate-binding proteins. However, the double jelly-roll major capsid protein (DJR-MCP), the hallmark of the enormously diverse viruses of the kingdom Bamfordvirae within the realm Varidnaviria, which includes bacterial and archaeal icosahedral viruses as well as eukaryotic giant viruses, has been perceived as a virus innovation that evolved by duplication and fusion of the SJR capsid proteins. Here we employ protein structure comparison to show that the DJR fold is represented in several widespread families of cellular proteins, including several groups of carbohydrate-active enzymes. We show that DJR-MCPs share a common ancestry with a distinct family of bacterial DJR proteins (DUF2961) involved in carbohydrate metabolism. Based on this finding, we propose a scenario in which bamfordviruses evolved from nonviral replicators, in particular plasmids, by recruiting a host protein for capsid formation. This sequence of events appears to be the general route of virus origin. The results of this work indicate that virus kingdoms Bamfordvirae, with the DJR-MCPs, and Helvetiavirae that possess two SJR-MCPs, have distinct origins, suggesting a reappraisal of the realm Varidnaviria.


Assuntos
Proteínas do Capsídeo/genética , Vírus/genética , DNA/genética , Vírus de DNA/genética , Genoma Viral/genética , Vírion/genética
2.
Nano Lett ; 24(34): 10650-10655, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39158094

RESUMO

In situ characterizations of charge injection dynamics, equilibrated concentration, and electric field distributions shed light on the critical mechanisms of quantum dot light-emitting diodes (QD-LEDs). In this work, we developed electrically excited transient absorption spectroscopy, which can provide the above key information, to investigate the efficiency roll-off of QD-LEDs. We found that the average electron populations per QD are low when QD-LEDs exhibit efficiency roll-off, excluding Auger recombination as the main cause. We also revealed that the weak electrical field inside the QD layer under forward biases has a negligible impact on the efficiency. Interestingly, we found that as the voltage increases the electron concentration in the QD layer saturates at very low levels. When combined with the concomitant efficiency roll-off, we propose electron leakage is the main loss at elevated driving voltages. We further demonstrate that increasing the electron confinement potential with the ZnS shell enables us to efficiently mitigate the efficiency roll-off.

3.
Diabetes Metab Res Rev ; 40(7): e3845, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39356275

RESUMO

AIMS: To assess whether impaired vestibular perception of self-motion is a risk factor for unsteadiness and falls in elderly patients with type 2 diabetes (T2D). MATERIALS AND METHODS: 113 participants (65-75 years old) with T2D underwent tests of roll and pitch discrimination, postural stability (Berg Balance Scale, Modified Romberg Test, and quantitative posturography), clinical examination and blood chemistry analyses. Falls 1-year after enrolment were self-reported. We performed cluster analysis based on the values of the vestibular motion thresholds, and logistic stepwise regression to compare the clinical-biochemical parameters between clusters. RESULTS: We identified two clusters (VC1 n = 65 and VC2 n = 48 participants). VC2 had significantly (p < 0.001) higher (poorer) thresholds than VC1: mean pitch threshold 1.62°/s (95% CI 1.48-1.78) in VC2 and 0.91°/s (95% CI 0.84-0.98) in VC1, mean roll threshold 1.34°/s (95% CI 1.21-1.48) in VC2 and 0.69°/s (95% CI 0.64-0.74) in VC1. Diabetes duration was significantly (p = 0.024) longer in VC2 (11.96 years, 95% CI 9.23-14.68) than in VC1 (8.37 years, 95% CI 6.85-9.88). Glycaemic control was significantly (p = 0.014) poorer in VC2 (mean HbA1c 6.74%, 95% CI 6.47-7.06) than in VC1 (mean HbA1c 6.34%, 95% CI 6.16-6.53). VC2 had a significantly higher incidence of postural instability than VC1, with a higher risk of failing the Modified Romberg Test C4 (RR = 1.57, χ2 = 5.33, p = 0.021), reporting falls during follow-up (RR = 11.48, χ2 = 9.40, p = 0.002), and greater postural sway in the medio-lateral direction (p < 0.025). CONCLUSIONS: Assessing vestibular motion thresholds identifies individuals with T2D at risk of postural instability due to altered motion perception and guides vestibular rehabilitation.


Assuntos
Acidentes por Quedas , Diabetes Mellitus Tipo 2 , Equilíbrio Postural , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Equilíbrio Postural/fisiologia , Feminino , Idoso , Acidentes por Quedas/estatística & dados numéricos , Masculino , Fatores de Risco , Percepção de Movimento/fisiologia , Seguimentos , Vestíbulo do Labirinto/fisiopatologia , Prognóstico , Doenças Vestibulares/fisiopatologia , Doenças Vestibulares/epidemiologia , Doenças Vestibulares/etiologia
4.
J Exp Biol ; 227(2)2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38149677

RESUMO

Cetaceans are capable of extraordinary locomotor behaviors in both water and air. Whales and dolphins can execute aerial leaps by swimming rapidly to the water surface to achieve an escape velocity. Previous research on spinner dolphins demonstrated the capability of leaping and completing multiple spins around their longitudinal axis with high angular velocities. This prior research suggested the slender body morphology of spinner dolphins together with the shapes and positions of their appendages allowed for rapid spins in the air. To test whether greater moments of inertia reduced spinning performance, videos and biologging data of cetaceans above and below the water surface were obtained. The principal factors affecting the number of aerial spins a cetacean can execute were moment of inertia and use of control surfaces for subsurface corkscrewing. For spinner dolphin, Pacific striped dolphin, bottlenose dolphin, minke whale and humpback whale, each with swim speeds of 6-7 m s-1, our model predicted that the number of aerial spins executable was 7, 2, 2, 0.76 and 1, respectively, which was consistent with observations. These data implied that the rate of subsurface corkscrewing was limited to 14.0, 6.8, 6.2, 2.2 and 0.75 rad s-1 for spinner dolphins, striped dolphins, bottlenose dolphins, minke whales and humpback whales, respectively. In our study, the moment of inertia of the cetaceans spanned a 21,000-fold range. The greater moments of inertia for the last four species produced large torques on control surfaces that limited subsurface corkscrewing motion and aerial maneuvers compared with spinner dolphins.


Assuntos
Golfinho Nariz-de-Garrafa , Jubarte , Stenella , Animais , Natação , Água
5.
World J Surg Oncol ; 22(1): 178, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971793

RESUMO

BACKGROUND: Any advantage of performing targeted axillary dissection (TAD) compared to sentinel lymph node (SLN) biopsy (SLNB) is under debate in clinically node-positive (cN+) patients diagnosed with breast cancer. Our objective was to assess the feasibility of the removal of the clipped node (RCN) with TAD or without imaging-guided localisation by SLNB to reduce the residual axillary disease in completion axillary lymph node dissection (cALND) in cN+ breast cancer. METHODS: A combined analysis of two prospective cohorts, including 253 patients who underwent SLNB with/without TAD and with/without ALND following NAC, was performed. Finally, 222 patients (cT1-3N1/ycN0M0) with a clipped lymph node that was radiologically visible were analyzed. RESULTS: Overall, the clipped node was successfully identified in 246 patients (97.2%) by imaging. Of 222 patients, the clipped lymph nodes were non-SLNs in 44 patients (19.8%). Of patients in cohort B (n=129) with TAD, the clipped node was successfully removed by preoperative image-guided localisation, or the clipped lymph node was removed as the SLN as detected on preoperative SPECT-CT. Among patients with ypSLN(+) (n=109), no significant difference was found in non-SLN positivity at cALND between patients with TAD and RCN (41.7% vs. 46.9%, p=0.581). In the subgroup with TAD with axillary lymph node dissection (ALND; n=60), however, patients with a lymph node (LN) ratio (LNR) less than 50% and one metastatic LN in the TAD specimen were found to have significantly decreased non-SLN positivity compared to others (27.6% vs. 54.8%, p=0.032, and 22.2% vs. 50%, p=0.046). CONCLUSIONS: TAD by imaging-guided localisation is feasible with excellent identification rates of the clipped node. This approach has also been found to reduce the additional non-SLN positivity rate to encourage omitting ALND in patients with a low metastatic burden undergoing TAD.


Assuntos
Axila , Neoplasias da Mama , Excisão de Linfonodo , Terapia Neoadjuvante , Neoplasia Residual , Biópsia de Linfonodo Sentinela , Humanos , Feminino , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/diagnóstico por imagem , Excisão de Linfonodo/métodos , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Estudos Prospectivos , Adulto , Biópsia de Linfonodo Sentinela/métodos , Idoso , Neoplasia Residual/cirurgia , Neoplasia Residual/patologia , Linfonodos/patologia , Linfonodos/cirurgia , Linfonodos/diagnóstico por imagem , Seguimentos , Prognóstico , Metástase Linfática , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos de Viabilidade
6.
J Artif Organs ; 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39327399

RESUMO

Improvements in the roll porous scaffold (RPS) 3D bioproduction technology will increase print density of 10-15 µm cells by ~ 20% up to ~ 1.5 × 108 cells/mL and purity of organoid formation by > 17%. The use of 360 and 1200 dpi inkjet printheads immediately enables biomanufacturing with 10-30 µm cells in a single organoid with performance > 1.8 L/h for 15 µm layer thickness. The spongy bioresorbable ribbon for RPS technology is designed to solve the problems of precise placement, leakage and increasing in the number of instantly useable cell types and superior to all currently dominant 3D bioprinting methods in speed, volume, and print density without the use of expensive equipment and components. The potential of RPS for parallel testing of new substances studied was not on animals, but using generated 3D biomodels "organ on a chip". Solid organoids are more suitable for personalized medicine with simultaneous checking of several treatment methods and drugs, targeted therapy for a specific patient in vitro using the 3D composition of his personal cells, and selection of the most effective ones with the least toxicity. Overcoming the shortage of organs for implantation and personal hormone replacement therapy for everyone was achieved using printed endocrine glands based on their DNA.

7.
Public Health ; 229: 84-87, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38412698

RESUMO

OBJECTIVES: Refugees and migrants (R&Ms) exhibited higher risk of COVID-19 infection, and higher mortality rates during the pandemic. Acknowledging these risks, R&Ms early in the pandemic were identified by WHO as a priority vaccination group in need of protection. The aim of this study was to assess the vaccination roll-out and uptake among R&Ms residing in Reception Identification Centers (RICs) and Reception Sites (RSs) in Greece, relative to the general population. STUDY DESIGN: Nationwide observational study. METHODS: Retrospective analysis of national vaccination routine data and population census data, collected and triangulated from multiple official/governmental sources. Weekly vaccine roll-out and uptake were calculated for the general Greek population and the R&M population, through the first year of the vaccination programme in Greece (December 2020-December 2021). RESULTS: Vaccine roll-out among migrants in RICs/RSs started with a 22-week delay, compared to the general population. By the end of the first year of the vaccination programme in Greece in December 2021, the national vaccination uptake among registered R&Ms residing in official reception facilities was 27.3 % for 1st dose and 4.7 % for booster dose; considerably lower compared to the general population (69.5 % uptake for 1st dose, 64.7 % for 2nd dose, and 32.0 % for 3rd dose). CONCLUSION: Delayed vaccine roll-out and low vaccine uptake among R&Ms in Greece are signs of low prioritisation and implementation failures in the R&M vaccination strategy. In face of future public health threats, lessons should be learned, and vaccine equity should be insured for all socially vulnerable and high-risk population groups.


Assuntos
COVID-19 , Refugiados , Migrantes , Humanos , Grécia/epidemiologia , Vacinas contra COVID-19 , Estudos Retrospectivos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinação
8.
Nano Lett ; 23(11): 4785-4792, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37220025

RESUMO

While the performance of metal halide perovskite light-emitting diodes (PeLEDs) has rapidly improved in recent years, their stability remains a bottleneck to commercial realization. Here, we show that the thermal stability of polymer hole-transport layers (HTLs) used in PeLEDs represents an important factor influencing the external quantum efficiency (EQE) roll-off and device lifetime. We demonstrate a reduced EQE roll-off, a higher breakdown current density of approximately 6 A cm-2, a maximum radiance of 760 W sr-1 m-2, and a longer device lifetime for PeLEDs using polymer HTLs with high glass-transition temperatures. Furthermore, for devices driven by nanosecond electrical pulses, a record high radiance of 1.23 MW sr-1 m-2 and an EQE of approximately 1.92% at 14.6 kA cm-2 are achieved. Thermally stable polymer HTLs enable stable operation of PeLEDs that can sustain more than 11.7 million electrical pulses at 1 kA cm-2 before device failure.

9.
J Sci Food Agric ; 104(11): 6461-6469, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38501369

RESUMO

BACKGROUND: Fried foods are favored for their unique crispiness, golden color and flavor, but they also face great challenge because of their high oil content, high calories and the existence of compounds such as acrylamide and polycyclic aromatic hydrocarbons. Long-term consumption of fried foods may adversely affect health. Therefore, it is necessary to explore fried foods with lower oil contents and a high quality to meet the demand. RESULTS: A method of enzyme treatment was explored to investigate the effects of maltogenic amylase (MA), transglutaminase (TG) and bromelain (BRO) on the physicochemical properties of the batter and the quality of fried spring roll wrapper (FSRW). The results showed that the MA-, TG- or BRO-treated batters had a significant shear-thinning behavior, especially with an increase in viscosity upon increasing TG contents. FSRW enhanced its fracturability from 419.19 g (Control) to 616.50 g (MA-6 U g-1), 623.49 g (TG-0.75 U g-1) and 644.96 g (BRO-10 U g-1). Meanwhile, in comparison with BRO and MA, TG-0.5 U g-1 endowed batter with the highest density and thermal stability. MA-15 U g-1 and TG-0.5 U g-1 displayed FSRW with uniform and dense pores, and significantly reduced its oil content by 18.05% and 25.02%, respectively. Moreover, compared to MA and TG, BRO-50 U g-1 improved the flavor of FSRW. CONCLUSION: MA, TG or BRO played a key role in affecting the physicochemical properties of the batter and the quality of FSRW. TG-0.5 U g-1 remarkly reduced the oil content of FSRW with a great potential in practical application. © 2024 Society of Chemical Industry.


Assuntos
Bromelaínas , Culinária , Transglutaminases , Transglutaminases/química , Bromelaínas/química , Viscosidade , Frutas/química , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/metabolismo , Farinha/análise , Paladar , Manipulação de Alimentos/métodos
10.
Angew Chem Int Ed Engl ; : e202416154, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39400436

RESUMO

Multi-resonance thermally activated delayed fluorescence (MR-TADF) molecules have experienced great success in organic light-emitting diodes (OLEDs) owing to their outstanding quantum efficiencies and narrow full width at half-maximums (FWHMs). However, the reverse intersystem crossing (RISC) rates of MR-TADF emitters are usually small, which will lead to relatively long triplet exciton lifetime and severe efficiency roll-off. Here, we report an effective molecular design strategy to introduce multichannel RISC pathways and thus increase RISC rates without compromising the color fidelity and emission efficiency by the "hybridized long-short axis (HLSA)" strategy. The TPA-CN-BN shows a near-unity photoluminescence quantum yield, rapid RISC rate of 1.4 × 105 s-1, narrow FWHM of 23 nm, and small singlet-triplet energy gap (ΔEST) of 0.06 eV in solution. The non-sensitized OLED based on TPA-CN-BN exhibits a narrowband emission with the FWHM of 31 nm, in company with external quantum efficiency (EQE) of 37.9%. Notably, the device exhibits the low efficiency roll-off as the EQEs maintain 34.8% and 21.8% at 100 and 1000 cd m-2, respectively, representing the best performance for single-host OLEDs based on the BCzBN skeleton. This study provides a fresh and promising approach to realize high-performance OLEDs with high color purity and remarkable device efficiency.

11.
J Neurophysiol ; 130(4): 910-924, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37609720

RESUMO

Rhythmic activity is ubiquitous in neural systems, with theta-resonant pyramidal neurons integrating rhythmic inputs in many cortical structures. Impedance analysis has been widely used to examine frequency-dependent responses of neuronal membranes to rhythmic inputs, but it assumes that the neuronal membrane is a linear system, requiring the use of small signals to stay in a near-linear regime. However, postsynaptic potentials are often large and trigger nonlinear mechanisms (voltage-gated ion channels). The goals of this work were to 1) develop an analysis method to evaluate membrane responses in this nonlinear domain and 2) explore phase relationships between rhythmic stimuli and subthreshold and spiking membrane potential (Vmemb) responses in models of theta-resonant pyramidal neurons. Responses in these output regimes were asymmetrical, with different phase shifts during hyperpolarizing and depolarizing half-cycles. Suprathreshold theta-rhythmic stimuli produced nonstationary Vmemb responses. Sinusoidal inputs produced "phase retreat": action potentials occurred progressively later in cycles of the input stimulus, resulting from adaptation. Sinusoidal current with increasing amplitude over cycles produced "phase advance": action potentials occurred progressively earlier. Phase retreat, phase advance, and subthreshold phase shifts were modulated by multiple ion channel conductances. Our results suggest differential responses of cortical neurons depending on the frequency of oscillatory input, which will play a role in neuronal responses to shifts in network state. We hypothesize that intrinsic cellular properties complement network properties and contribute to in vivo phase-shift phenomena such as phase precession, seen in place and grid cells, and phase roll, also observed in hippocampal CA1 neurons.NEW & NOTEWORTHY We augmented electrical impedance analysis to characterize phase shifts between large-amplitude current stimuli and nonlinear, asymmetric membrane potential responses. We predict different frequency-dependent phase shifts in response excitation vs. inhibition, as well as shifts in spike timing over multiple input cycles, in theta-resonant pyramidal neurons. We hypothesize that these effects contribute to navigation-related phenomena such as phase precession and phase roll. Our neuron-level hypothesis complements, rather than falsifies, prior network-level explanations of these phenomena.


Assuntos
Neurônios , Células Piramidais , Células Piramidais/fisiologia , Neurônios/fisiologia , Potenciais de Ação/fisiologia , Potenciais da Membrana/fisiologia , Hipocampo/fisiologia , Ritmo Teta/fisiologia
12.
BMC Plant Biol ; 23(1): 19, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627562

RESUMO

This study aims to provide insights into plant-insect interaction during the formation and development of open gall structure on the leaves of Robinia pseudoacacia during gall formation by Obolodiplosis robiniae. This was the first time such far-reaching studies were performed at a biochemical and anatomical level. The gall wall is created from a few thick cells covered with epidermis. This parenchymatous nutritive tissue is rich in starch. Sclerenchyma only occurs around the vascular bundles as a result of the lignification of the parenchyma of the bundle sheaths. The level of reactive oxygen species (ROS) in the new structure was reduced and catalase activity was inhibited, which suggests another pathway of ROS decomposition - e.g. by ascorbate or glutathione peroxidase. The gall structure was combined with an increasing level of protein and non-protein thiols. Phenols seems to be a good protective factor; whose level was lower in infected leaflets. Levels of MUFA (monosaturated fatty acids) and SFA (saturated fatty acids) rose, probably as source of food for insects. The amount of fatty acid is positively correlated with the plant response. We detected that non infected leaflets produced C6:0 (hexanoic acid) and C8:0 (octanoic acid) fatty acids connected with odor. Changes in gall color as they develop are connected with photosynthetic pigments degradation (mainly chlorophylls) where the pathway of astaxanthin transformation to fatty acid is considered to be the most important process during gall maturation. Nutritive tissue is composed mainly of octadecanoic acid (C18:0) - a main source of food for O. robiniae.


Assuntos
Dípteros , Robinia , Animais , Espécies Reativas de Oxigênio , Insetos , Plantas , Ácidos Graxos , Folhas de Planta/fisiologia , Tumores de Planta
13.
Small ; 19(33): e2301533, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36970781

RESUMO

Laminated graphene film has great potential in compact high-power capacitive energy storage owing to the high bulk density and opened architecture. However, the high-power capability is usually limited by tortuous cross-layer ion diffusion. Herein, microcrack arrays are fabricated in graphene films as fast ion diffusion channels, converting tortuous diffusion into straightforward diffusion while maintaining a high bulk density of 0.92 g cm-3 . Films with optimized microcrack arrays exhibit sixfold improved ion diffusion coefficient and high volumetric capacitance of 221 F cm-3 (240 F g-1 ), representing a critical breakthrough in optimizing ion diffusion toward compact energy storage. This microcrack design is also efficient for signal filtering. Microcracked graphene-based supercapacitor with 30 µg cm-2  mass loading exhibits characteristic frequency up to 200 Hz with voltage window up to 4 V, showing high promise for compact, high-capacitance alternating current (AC) filtering. Moreover, a renewable energy system is conducted using microcrack-arrayed graphene supercapacitors as filter-capacitor and energy buffer, filtering and storing the 50 Hz AC electricity from a wind generator into the constant direct current, stably powering 74 LEDs, demonstrating enormous potential in practical applications. More importantly, this microcracking approach is roll-to-roll producible, which is cost-effective and highly promising for large-scale manufacture.

14.
Small ; : e2309233, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38050935

RESUMO

Perovskite light-emitting diodes (PeLEDs) have shown incalculable application potential in the fields of next-generation displays and light communication owing to the rapidly increased external quantum efficiencies (EQEs). However, most PeLEDs obtain a maximum EQE at small current density (J) region and suffer from severe efficiency roll-off in different extents. Herein, it is demonstrated that the dopant with large dipole moment like KBF4 facilitates the effective dielectric regulation of perovskite emissive layer. The increased dielectric constant lowers the exciton binding energy and suppresses the Auger recombination of the 2D/3D segregated perovskite structure, which improves the photoluminescence quantum yield remarkably at an excitation intensity up to 103  mW cm-2 . Accordingly, the top-emission PeLED that delivers a high maximum EQE above 20% is fabricated and can retain EQE > 10% at an extremely high J of 708 mA cm-2 . These results represent one of the most efficient top-emission PeLEDs with ultra-low efficiency roll-off, which provide a viable methodology for tuning the dielectric response of perovskite films for improved high radiance performance of perovskite electroluminescence devices.

15.
Small ; 19(38): e2301744, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37231559

RESUMO

Application of Si anodes is hindered by severe capacity fading due to pulverization of Si particles during the large volume changes of Si during charge/discharge and repeated formation of the solid-electrolyte interphase. To address these issues, considerable efforts have been devoted to the development of Si composites with conductive carbons (Si/C composites). However, Si/C composites with high C content inevitably show low volumetric capacity because of low electrode density. For practical applications, the volumetric capacity of a Si/C composite electrode is more important than gravimetric capacity, but volumetric capacity in pressed electrodes is rarely reported. Herein, a novel synthesis strategy is demonstrate for a compact Si nanoparticle/graphene microspherical assembly with interfacial stability and mechanical strength achieved by consecutively formed chemical bonds using 3-aminopropyltriethoxysilane and sucrose. The unpressed electrode (density: 0.71 g cm-3 ) shows a reversible specific capacity of 1470 mAh g-1 with a high initial coulombic efficiency of 83.7% at a current density of 1 C-rate. The corresponding pressed electrode (density: 1.32 g cm-3 ) exhibits high reversible volumetric capacity of 1405 mAh cm-3 and gravimetric capacity of 1520 mAh g-1 with a high initial coulombic efficiency of 80.4% and excellent cycling stability of 83% over 100 cycles at 1 C-rate.

16.
J Virol ; 96(17): e0060422, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35939401

RESUMO

Enterovirus 70 (EV70) is a human pathogen belonging to the family Picornaviridae. EV70 is transmitted by eye secretions and causes acute hemorrhagic conjunctivitis, a serious eye disease. Despite the severity of the disease caused by EV70, its structure is unknown. Here, we present the structures of the EV70 virion, altered particle, and empty capsid determined by cryo-electron microscopy. The capsid of EV70 is composed of the subunits VP1, VP2, VP3, and VP4. The partially collapsed hydrophobic pocket located in VP1 of the EV70 virion is not occupied by a pocket factor, which is commonly present in other enteroviruses. Nevertheless, we show that the pocket can be targeted by the antiviral compounds WIN51711 and pleconaril, which block virus infection. The inhibitors prevent genome release by stabilizing EV70 particles. Knowledge of the structures of complexes of EV70 with inhibitors will enable the development of capsid-binding therapeutics against this virus. IMPORTANCE Globally distributed enterovirus 70 (EV70) causes local outbreaks of acute hemorrhagic conjunctivitis. The discharge from infected eyes enables the high-efficiency transmission of EV70 in overcrowded areas with low hygienic standards. Currently, only symptomatic treatments are available. We determined the structures of EV70 in its native form, the genome release intermediate, and the empty capsid resulting from genome release. Furthermore, we elucidated the structures of EV70 in complex with two inhibitors that block virus infection, and we describe the mechanism of their binding to the virus capsid. These results enable the development of therapeutics against EV70.


Assuntos
Antivirais , Capsídeo , Enterovirus Humano D , Antivirais/farmacologia , Capsídeo/ultraestrutura , Proteínas do Capsídeo , Conjuntivite Hemorrágica Aguda/virologia , Microscopia Crioeletrônica , Enterovirus Humano D/efeitos dos fármacos , Enterovirus Humano D/ultraestrutura , Humanos , Oxidiazóis/farmacologia , Oxazóis/farmacologia , Vírion/efeitos dos fármacos , Vírion/ultraestrutura
17.
AIDS Behav ; 27(8): 2695-2702, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36692609

RESUMO

Collection and use of self-reported HIV sexual risk-behaviors to identify pre-exposure prophylaxis (PrEP) candidates is common practice in PrEP providing and referral services. Critiques of this strategy highlight overreliance on self-report and contribution to ongoing PrEP stigma. As an alternative (or complimentary) approach, we evaluated a 5-item Concerns Based Conversation Starter (CBCS) that could be used to identify individuals who could benefit from PrEP. The CBCS was included in the 2019 cycle of the American Men's Internet Survey. Item responses were characterized overall and in relation to CDC risk-based PrEP indication and reported willingness to use PrEP. In total, 1606 HIV-negative men who have sex with men not on PrEP were evaluated. Of these, 50% were below the age of 25, 11% Black, 16% Latino, and 64% White. Across the sample, 61% (986) met risk-based criteria for PrEP indication, 80% (1278) were identified by the CBCS, and 52% (835) were flagged by both. The CBCS uniquely identified 28% (443) for follow-up PrEP discussions that would have been missed by a risk-based only approach. Only 9% (151) of the sample had risk-based indication but did not report concerns. Over half of those flagged by the CBCS expressed willingness to use PrEP. The CBCS identified more people than a risk-based indication approach, with most also reporting an interest in using PrEP. A small percentage of risk-indicated participants were 'missed' by the CBCS. As PrEP options and access points expand, implementation tools like the CBCS can facilitate more wide-scale, values-focused PrEP implementation.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Masculino , Humanos , Homossexualidade Masculina , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , Comportamento Sexual
18.
Mol Biol Rep ; 50(3): 2171-2181, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36565419

RESUMO

BACKGROUND: It is believed that viruses affect potato yield more than any other pathogens worldwide. METHOD AND RESULTS: We report here on a survey of the four most common potato viruses in the Tokat Province of northern Turkey. Leaf samples were collected from potato plants showing signs of viral diseases in five districts of the province. Over 400 leaf samples were tested using RT-PCR with virus-specific primers. Among the one or more viruses detected in 218 (52%) leaf samples, Potato virus Y (PVY) was the most common (47.1%), followed by potato virus S (PVS; 16.7%), potato virus X (PVX; 6.0%) and potato leaf roll virus (PLRV; 5.3%). The most common mixed infections were PVY + PVS (6.9%). A phylogenetic analysis of the gene sequences showed all Turkish PVS isolates to be clustered with the PVSO group, two PVY isolates with the PVYN-WI group and one isolate with the PVYNTN group. Turkish PVX isolates are in the Type X group of the two major PVX isolate groups. The Turkish PLRV isolates were separated into two major groups depending on the results of the phylogenetic analysis, with six cases in Group 1 and one in Group 2. CONCLUSIONS: PVY, PVX, PVS and PLRV were detected in potato production areas in Tokat. A phylogenetic comparison of the gene sequences revealed all Turkish isolates to be immigrant members of the world populations of these viruses. Our results emphasize the importance of the strict quarantine control of plant materials entering Turkey.


Assuntos
Potyvirus , Solanum tuberosum , Filogenia , Prevalência , Turquia , Primers do DNA , Potyvirus/genética , Doenças das Plantas
19.
Proc Natl Acad Sci U S A ; 117(35): 21155-21161, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817417

RESUMO

Ultrathick battery electrodes are appealing as they reduce the fraction of inactive battery parts such as current collectors and separators. However, thick electrodes are difficult to dry and tend to crack or flake during production. Moreover, the electrochemical performance of thick electrodes is constrained by ion and electron transport as well as fast capacity degradation. Here, we report a thermally induced phase separation (TIPS) process for fabricating thick Li-ion battery electrodes, which incorporates the electrolyte directly in the electrode and alleviates the need to dry the electrode. The proposed TIPS process creates a bicontinuous electrolyte and electrode network with excellent ion and electron transport, respectively, and consequently achieves better rate performance. Using this process, electrodes with areal capacities of more than 30 mAh/cm2 are demonstrated. Capacity retentions of 87% are attained over 500 cycles in full cells with 1-mm-thick anodes and cathodes. Finally, we verified the scalability of the TIPS process by coating thick electrodes continuously on a pilot-scale roll-to-roll coating tool.

20.
Sensors (Basel) ; 23(18)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37765913

RESUMO

Roll-to-roll manufacturing systems have been widely adopted for their cost-effectiveness, eco-friendliness, and mass-production capabilities, utilizing thin and flexible substrates. However, in these systems, defects in the rotating components such as the rollers and bearings can result in severe defects in the functional layers. Therefore, the development of an intelligent diagnostic model is crucial for effectively identifying these rotating component defects. In this study, a quantitative feature-selection method, feature partial density, to develop high-efficiency diagnostic models was proposed. The feature combinations extracted from the measured signals were evaluated based on the partial density, which is the density of the remaining data excluding the highest class in overlapping regions and the Mahalanobis distance by class to assess the classification performance of the models. The validity of the proposed algorithm was verified through the construction of ranked model groups and comparison with existing feature-selection methods. The high-ranking group selected by the algorithm outperformed the other groups in terms of training time, accuracy, and positive predictive value. Moreover, the top feature combination demonstrated superior performance across all indicators compared to existing methods.

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