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1.
Langmuir ; 40(14): 7560-7568, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38553424

RESUMO

It is essential and challenging to develop green and cost-effective solar cells to meet the energy demands. Solar cells with a perovskite light-harvesting layer are the most promising technology to propel the world toward next-generation solar energy. Formamidinium lead tri-iodide (FAPbI3)-based perovskite solar cells (F-PSCs), with their considerable performance, offer cost-effective solar cells. One of the major issues that the PSC community is now experiencing is the stability of α-FAPbI3 at relatively low temperatures. In this study, we fabricated FAPbI3-PSCs using cyclohexane (CHX) material via a two-step deposition method. For this purpose, CHX is added to the formamidinium iodide:methylammonium chloride (FAI:MACl) solution as an additive and used to form a better FAPbI3 layer by controlling the reaction between FAI and lead iodide (PbI2). The CHX additive induces the reaction of undercoordinated Pb2+ with FAI material and produces an α-FAPbI3 layer with low charge traps and large domains. In addition, the CHX-containing FAPbI3 layers show higher carrier lifetimes and facilitate carrier transfer in F-PSCs. The CHX-modified F-PSCs yield a high champion efficiency of 22.84% with improved ambient and thermal stability behavior. This breakthrough provides valuable findings regarding the formation of a desirable FAPbI3 layer for photovoltaic applications and holds promise for the industrialization of F-PSCs.

2.
Langmuir ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38330073

RESUMO

The oxygen sensors with limiting current derived from a dense diffusion barrier have an excellent advantage of detecting oxygen partial pressure by controlling the ratio of air and fuel in combustion environments. Therefore, AgNb1-xTixO3-δ (wherein x varies from 0.1 to 0.3) was prepared as such a dense diffusion barrier layer for sensor application. Among the investigated compositions as a new condensed barrier for the diffusion of sensors, AgNb1-xTixO3-δ (x = 0.1, 0.2, 0.3) exhibits oxygen ionic conductivities from 1.37 × 10-4 to 5.78 × 10-3 S·cm-1 in the temperature range of 600-900 °C and outstanding stable electrochemical properties. Herein, we employ these novel materials as dense diffusion barriers and 8 mol % zirconia stabilized by yttria (8YSZ) as a solid-state electrolyte for the fabrication of the oxygen sensors with limiting current. We observed a direct connection between the limiting current and oxygen content within the interval of 0.5-5.0 mol % at 800 °C and a low working voltage. The increase of Ti-doping amount in AgNbO3 accelerates the sensing response to oxygen gas and promotes the service life of the sensor.

3.
Ann Emerg Med ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38888531

RESUMO

STUDY OBJECTIVE: The real-world effectiveness and safety of a 0/1-hour accelerated protocol using high-sensitivity cardiac troponin (hs-cTn) to exclude myocardial infarction (MI) compared to routine care in the United States is uncertain. The objective was to compare a 0/1-hour accelerated protocol for evaluation of MI to a 0/3-hour standard care protocol. METHODS: The RACE-IT trial was a stepped-wedge, randomized trial across 9 emergency departments (EDs) that enrolled 32,609 patients evaluated for possible MI from July 2020 through April 2021. Patients undergoing high-sensitivity cardiac troponin I testing with concentrations less than or equal to 99th percentile were included. Patients who had MI excluded by the 0/1-hour protocol could be discharged from the ED. Patients in the standard care protocol had 0- and 3-hour troponin testing and application of a modified HEART score to be eligible for discharge. The primary endpoint was the proportion of patients discharged from the ED without 30-day death or MI. RESULTS: There were 13,505 and 19,104 patients evaluated in the standard care and accelerated protocol groups, respectively, of whom 19,152 (58.7%) were discharged directly from the ED. There was no significant difference in safe discharges between standard care and the accelerated protocol (59.5% vs 57.8%; adjusted odds ratio (aOR)=1.05, 95% confidence interval [CI] 0.95 to 1.16). At 30 days, there were 90 deaths or MIs with 38 (0.4%) in the standard care group and 52 (0.4%) in the accelerated protocol group (aOR=0.84, 95% CI 0.43 to 1.68). CONCLUSION: A 0/1-hour accelerated protocol using high-sensitivity cardiac troponin I did not lead to more safe ED discharges compared with standard care.

4.
Phys Chem Chem Phys ; 26(4): 3229-3239, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38193862

RESUMO

Perovskites composed of inorganic cesium (Cs) halide provide a route to thermally resistant solar cells. Nevertheless, the use of hole-transporting layers (HTLs) with hydrophobic additives is constrained by moisture-induced phase deterioration. Due to significant electrical loss, dopant-free HTLs are unable to produce practical solar cells. In this article, we designed a two-dimensional 1,3,6,8-tetrakis[5-(N,N-di(p-(methylthio)phenyl)amino-p-phenyl)-thiophen-2-yl]pyrene (termed SMe-TATPyr) molecule as a new HTL to regulate electrical loss in lead-free perovskite solar cells (PSCs). We optimized the power conversion efficiency (PCE) of PSCs based on mixed tin (Sn)/germanium (Ge) halide perovskite (CsSn0.5Ge0.5I3) by exploring different factors, such as the deep and shallow levels of defects, density of states at the valence band (NV), thickness of the perovskite film, p-type doping concentration (NA) of HTL, the series and shunt resistances, and so on. We carried out comparative research by employing the 1D-SCAPS (a solar cell capacitance simulator) analysis tool. Through optimization of the PSC, we obtained the highest parameters in the simulated solar cell structure of fluorine tin oxide (FTO)/titanium dioxide (TiO2)/CsSn0.5Ge0.5I3/SMe-TATPyr/gold (Au), and the PCE reached up to 20% with a fill factor (FF) of 81.89%.

5.
Indian J Public Health ; 68(2): 329-332, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38953830

RESUMO

An outbreak of dengue fever struck Tikarapada village, Rayagada district (April 2020). Among 117 fever cases, 49 tested positive for the dengue NS1 antigen. To identify mosquito-related factors in the outbreak, a survey of 101 houses found Aedes breeding sites in 11.6% of containers. Aedes aegypti (79%) and Aedes albopictus (21%) emerged from collected pupae. The village exhibited high (house index = 24.8), (container index = 11.6), (pupal index = 32.7), and (Breteau index = 40.6) indices. The findings confirmed the presence of Aedes and ample breeding sites, suggesting their role in the outbreak. A report recommending integrated vector control measures was submitted to district and state health authorities.


Assuntos
Aedes , Dengue , Surtos de Doenças , Mosquitos Vetores , Dengue/epidemiologia , Aedes/virologia , Animais , Humanos , Índia/epidemiologia , Masculino , Adulto , Feminino , Adolescente , Criança , Pessoa de Meia-Idade , Vírus da Dengue , Adulto Jovem , Controle de Mosquitos , Pré-Escolar
6.
Phys Chem Chem Phys ; 25(6): 5122-5129, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36722994

RESUMO

Using an ab initio framework and non-equilibrium Green's function technique, the effect of hydrogen and fluorine atom passivation on the electronic and transport properties of borophene nanoribbons (BNRs) are explored. For zigzag edge states, we have explored all potentially stable combinations of hydrogen and fluorine passivation. Fluorine passivation leads to thermodynamically stable structures with improved stability for the increased concentration of F atoms, according to our binding energy (Eb) calculations. Furthermore, density-of-states and dispersion relation (E-k structures) computations indicate that fluorine-passivated BNRs are primarily metallic in nature. We proposed these nanostructures for their use in metal interconnects because of their increased metallicity. We have used the typical two-probe setup to calculate the critical parameters like quantum resistance (RQ), kinetic inductance (LK), and quantum capacitance (CQ) to evaluate their performance as metal interconnects. Because they have the lowest estimated values of LK = 26.1 nH µm-1, and CQ = 399 pF cm-1, the zigzag BNRs (ZBNRs) with two edge fluorinated (F-BNR-F) nanostructures may be considered as a promising candidate for nanoscale interconnect applications.

7.
Phys Chem Chem Phys ; 25(24): 16459-16468, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37306330

RESUMO

Enhanced radiative efficiency, long carrier lifetimes, and high carrier mobilities are hallmarks of perovskite solar cells. Considering this, complete cells experience large nonradiative recombination losses that restrict their VOC considerably below the Shockley-Queisser limit. Auger recombination, which involves two free photo-induced carriers and a trapped charge carrier, is one potential mechanism. Herein, the effects of Auger capture coefficients in mixed-cation perovskites are analyzed employing SCAPS-1D computations. It is demonstrated that VOC and FF are severely decreased with an increase in the acceptor concentration and Auger capture coefficients of perovskites, thus reducing the device performance. When the Auger capture coefficient is increased to 10-20 cm6 s-1 under the acceptor concentration of 1016 cm-3, the performance is drastically lowered from 21.5% (without taking Auger recombination into account) to 9.9%. The findings suggest that in order to increase the efficiency of perovskite solar cells and prevent the effects of Auger recombination, the Auger recombination coefficients should be less than 10-24 cm6 s-1.

8.
Molecules ; 28(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36985473

RESUMO

The goal of the current work was to create an antibacterial agent by using polycaprolactone/chitosan (PCL/CH) nanofibers loaded with Cordia myxa fruit extract (CMFE) as an antimicrobial agent for wound dressing. Several characteristics, including morphological, physicomechanical, and mechanical characteristics, surface wettability, antibacterial activity, cell viability, and in vitro drug release, were investigated. The inclusion of CMFE in PCL/CH led to increased swelling capability and maximum weight loss. The SEM images of the PCL/CH/CMFE mat showed a uniform topology free of beads and an average fiber diameter of 195.378 nm. Excellent antimicrobial activity was shown towards Escherichia coli (31.34 ± 0.42 mm), Salmonella enterica (30.27 ± 0.57 mm), Staphylococcus aureus (21.31 ± 0.17 mm), Bacillus subtilis (27.53 ± 1.53 mm), and Pseudomonas aeruginosa (22.17 ± 0.12 mm) based on the inhibition zone assay. The sample containing 5 wt% CMFE had a lower water contact angle (47 ± 3.7°), high porosity, and high swelling compared to the neat mat. The release of the 5% CMFE-loaded mat was proven to be based on anomalous non-Fickian diffusion using the Korsmeyer-Peppas model. Compared to the pure PCL membrane, the PCL-CH/CMFE membrane exhibited suitable cytocompatibility on L929 cells. In conclusion, the fabricated antimicrobial nanofibrous films demonstrated high bioavailability, with suitable properties that can be used in wound dressings.


Assuntos
Quitosana , Cordia , Nanofibras , Frutas , Antibacterianos/farmacologia , Poliésteres/farmacologia , Bandagens
9.
Molecules ; 28(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37049692

RESUMO

A new series of ternary metal complexes, including Co(II), Ni(II), Cu(II), and Zn(II), were synthesized and characterized by elemental analysis and diverse spectroscopic methods. The complexes were synthesized from respective metal salts with Schiff's-base-containing amino acids, salicylaldehyde derivatives, and heterocyclic bases. The amino acids containing Schiff bases showed promising pharmacological properties upon complexation. Based on satisfactory elemental analyses and various spectroscopic techniques, these complexes revealed a distorted, square pyramidal geometry around metal ions. The molecular structures of the complexes were optimized by DFT calculations. Quantum calculations were performed with the density functional method for which the LACVP++ basis set was used to find the optimized molecular structure of the complexes. The metal complexes were subjected to an electrochemical investigation to determine the redox behavior and oxidation state of the metal ions. Furthermore, all complexes were utilized for catalytic assets of a multi-component Mannich reaction for the preparation of -amino carbonyl derivatives. The synthesized complexes were tested to determine their antibacterial activity against E. coli, K. pneumoniae, and S. aureus bacteria. To evaluate the cytotoxic effects of the Cu(II) complexes, lung cancer (A549), cervical cancer (HeLa), and breast cancer (MCF-7) cells compared to normal cells, cell lines such as human dermal fibroblasts (HDF) were used. Further, the docking study parameters were supported, for which it was observed that the metal complexes could be effective in anticancer applications.


Assuntos
Complexos de Coordenação , Humanos , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Bases de Schiff/farmacologia , Bases de Schiff/química , Valina , Escherichia coli , Staphylococcus aureus , Metais/química , Antibacterianos/farmacologia , Antibacterianos/química , Ligantes , Cobre/química
10.
AAPS PharmSciTech ; 24(7): 190, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726590

RESUMO

A severe form of autoimmune-mediated inflammatory bowel disease (IBD) is termed as ulcerative colitis (UC) which ultimately results in significant mucosal damage and ulceration. Herbal remedies may be employed as an alternative for treatment of UC instead of conventional medications such as Sulfasalazine. Promising natural remedies for the treatment of IBD, including colitis, are propolis extract (PP) and thymoquinone (TQ). This study is aimed at assessing the potential of liposomal formulations of TQ and Egyptian PP in combination therapy on improving their therapeutic efficacy against ulcerative colitis in order to maximize the potential of their beneficial clinical effects. Clinical, biochemical, and histological evaluations of colonic mucosal damage and inflammation were evaluated. The results exhibited a significant increase in tissue MDA, TNFα, and nitrite levels with activation of caspase-3 in the acetic acid-induced colitis group, which is predominantly downregulated in the treatment groups. The prepared formulations of TQ and PP revealed liposomal vesicles in a nanoscale size (192 ± 20.3 and 98.2 ± 20.3 nm, respectively) and accepted stability indicated with a zeta potential of 19.3 ± 0.11 and 17.1 ± 0.25 mV, respectively. They showed an entrapment efficiency of 85.3 ± 12.6% and 69.3 ± 11.8%, respectively. At comparable doses, combination therapy with thymoquinone liposomes and propolis liposomes considerably outperformed free TQ and free PP in reducing inflammation of UC as shown in the present study by clinical, biochemical, and histological evaluations.


Assuntos
Colite Ulcerativa , Colite , Própole , Humanos , Ácido Acético , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Lipossomos , Colite/induzido quimicamente , Colite/tratamento farmacológico , Inflamação
11.
Catheter Cardiovasc Interv ; 100(1): 163-168, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35568977

RESUMO

OBJECTIVE: We aim to report on the efficacy and safety of large bore venous access (LBVA) preclosure with Perclose™ (Abbott Vascular Devices) suture-mediated device use following transcatheter edge-to-edge (TEER) and replacement (TMVR). BACKGROUND: Patients requiring TEER and TMVR require LBVA. Clinical outcome data on the use of suture-mediated devices for LBVA site closure are limited. METHODS: Between 2012 and 2019, 354 consecutive high-risk patients with mitral valvular heart disease underwent TEER (n = 287) with MitraClip and TMVR (n = 67) with Edwards Sapien Valves. Patients had LBVA with 24 or 16 French sheaths. All patients underwent preclosure of LBVA except for one that underwent manual hemostasis. RESULTS: There were no closure device failures. None of the cases required surgical repair of the access site following venous preclosure. Two cases had large hematomas (>6 cm) following Perclose in each group. Six cases had small hematomas (<6 cm and >2 cm) with three in each group. There was one major bleeding using Mitral Valve Academic Research Consortium 2 definition (retroperitoneal bleed from arterial puncture) unrelated to the venous closure. Transfusion related to vascular access complication was required in five cases. There were two immediate acute deep venous thromboses postprocedure; one of which occurred after preclosure. There were no arteriovenous malformations, pseudoaneurysms, or access site infections reported following Perclose. CONCLUSION: In this large sample size analysis, Proglide preclosure technique is a feasible and safe alternative approach to achieving hemostasis after removal of LBVA sheaths in patients undergoing TEER and TMVR. Randomized trials are needed to compare the different modalities of hemostasis.


Assuntos
Doenças das Valvas Cardíacas , Dispositivos de Oclusão Vascular , Doenças das Valvas Cardíacas/cirurgia , Hematoma/etiologia , Hemorragia/etiologia , Hemorragia/prevenção & controle , Humanos , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Técnicas de Sutura/efeitos adversos , Resultado do Tratamento , Dispositivos de Oclusão Vascular/efeitos adversos
12.
BMC Med Educ ; 22(1): 348, 2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35525940

RESUMO

BACKGROUND: This study aimed to investigate the impact of interactive lecture (IL) and team-based learning (TBL) on improving clinical reasoning skills (CRSs) and achieving learning outcomes (LO). Students' feedback was obtained about the strategies. METHODS: This study was carried out at the Faculty of Medicine in Rabigh, King Abdulaziz University, Jeddah, Saudi Arabia. Two modules, endocrinology, and emergency were selected. Students of each batch in both modules were divided into two arms. With a randomized crossover design, IL & TBL were used for two separate topics in each module. After each topic, a quiz in the form of well-structured MCQs was taken. A questionnaire was designed to obtain students' feedback. SPSS version 23 was used to analyse results. The difference between the mean values was calculated by Student's t-test. Feedback data is presented as frequency. P-value ≤ 0.05 was considered statistically significant. RESULTS: Learning outcomes were achieved by all groups in two modules, with both instructional strategies, IL and TBL. Students attempted >70% correct answers. However, in the emergency module, the groups with TBL as the instructional strategy performed better in quiz1 and quiz 2 (p = 0.026 and p = 0.016, respectively). Similarly, in the endocrinology module (3rd year), although the groups with TBL as the instructional strategy performed better in both quizzes, it was significant in quiz1 (p = 0.02). The difficulty indices of the clinical reasoning questions (CRQ) were used as the parameters for comparison. In the emergency module, group1, in quiz1, with TBL as an instructional strategy performed better in the CRQ (p = 0.017), while in quiz2, group2 with TBL as the instructional strategy performed better (p < 0.001). Group1 of the third-year students (endocrinology module) performed better in the CRQ in quiz 1 with TBL as an instructional strategy than group 2 with IL (p = 0.04). Mostly, students in both modules preferred TBL over IL, and especially they liked team application. Students perceived that TBL was a better strategy to learn CRS. CONCLUSIONS: Students achieved LOs and CRS better with TBL as an instructional strategy. They preferred TBL over IL. It is suggested to include TBL, or increase its percentage, in the curriculum.


Assuntos
Raciocínio Clínico , Aprendizagem Baseada em Problemas , Estudos Cross-Over , Avaliação Educacional/métodos , Processos Grupais , Humanos
13.
Ecotoxicol Environ Saf ; 212: 112008, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33578129

RESUMO

Pollutants can have severe detrimental effects on insects, even at sublethal doses, damaging developmental and cognitive processes involved in crucial behaviours. Agrochemicals have been identified as important causes of pollinator declines, but the impacts of other anthropogenic compounds, such as metallic trace elements in soils and waters, have received considerably less attention. Here, we exposed colonies of the European honey bee Apis mellifera to chronic field-realistic concentrations of lead in food and demonstrated that consumption of this trace element impaired bee cognition and morphological development. Honey bees exposed to the highest of these low concentrations had reduced olfactory learning performances. These honey bees also developed smaller heads, which may have constrained their cognitive functions as we show a general relationship between head size and learning performance. Our results demonstrate that lead pollutants, even at trace levels, can have dramatic effects on honey bee cognitive abilities, potentially altering key colony functions and the pollination service.


Assuntos
Abelhas/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Chumbo/toxicidade , Reversão de Aprendizagem/efeitos dos fármacos , Animais , Abelhas/fisiologia , Cefalometria , Cognição/efeitos dos fármacos , Relação Dose-Resposta a Droga , Cabeça/anatomia & histologia , Polinização
14.
Malar J ; 19(1): 402, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33172495

RESUMO

BACKGROUND: The success of malaria control using long-lasting insecticidal nets (LLINs) is threatened by pyrethroid resistance developed by the malaria vectors, worldwide. To combat the resistance, synergist piperonyl butoxide (PBO) incorporated LLINs is one of the available options. In the current phase II hut trial, the efficacy of Veeralin®LN (an alpha-cypermethrin and PBO-incorporated net) was evaluated against Anopheles culicifacies, a pyrethroid resistant malaria vector. METHODS: The performance of Veeralin®LN was compared with MAGNet®LN and untreated net in reducing the entry, induced exit, mortality and blood feeding inhibition of target vector species. RESULTS: The performance of Veeralin was equal to MAGNet in terms of reducing hut entry, inhibiting blood feeding and inducing exophily, and with regard to causing mortality Veeralin was better than MAGNet. When compared to untreated net, a significant reduction in hut entry and blood feeding and an increase in exophily and mortality were observed with Veeralin. In cone bioassays, unwashed Veeralin caused > 80% mortality of An. culicifacies. CONCLUSIONS: Veeralin performed equal to (entry, exit, feeding) or better than (mortality in huts and cone bioassays) MAGNet and could be an effective tool against pyrethroid resistant malaria vectors.


Assuntos
Anopheles , Mosquiteiros Tratados com Inseticida , Inseticidas , Controle de Mosquitos , Butóxido de Piperonila , Piretrinas , Animais , Feminino , Índia
15.
J Cell Physiol ; 234(6): 9168-9183, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30317604

RESUMO

In case of a life-threatening, stressful event, the body prepares for an emergency. Indeed, the lung is unique in which alveolar cells are constantly exposed to physical and chemical stresses. This study aimed to study the impact of immobilization stress on the blood-air barrier and how it initiate and maintain an inflammatory response, plus determining the resolution of lung inflammation and repair. There was a significant increase in the plasma levels of stress markers "corticosterone and catecholamines" with a decrease in surfactant protein A (a lung-injury marker). Chronic stress produced a significant increase in the pulmonary oxidative and inflammatory markers malondialdehyde, tumor necrosis factor α, and induced nitric oxide synthase when compared with that of acute stress. Both stresses provoked marked pulmonary morphological and ultrastructural changes with a significant increase in caspase-3 immunoexpression. There was increasing evidence of lung's capacity for repair. This process involved edema resolution, cell proliferation, and tissue remodeling in improving the lung-injury, oxidative, and inflammatory markers.


Assuntos
Remodelação das Vias Aéreas , Células Epiteliais Alveolares/ultraestrutura , Células Endoteliais/ultraestrutura , Lesão Pulmonar/patologia , Pulmão/ultraestrutura , Restrição Física , Estresse Psicológico/complicações , Doença Aguda , Células Epiteliais Alveolares/metabolismo , Animais , Apoptose , Biomarcadores/sangue , Proliferação de Células , Doença Crônica , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Mediadores da Inflamação/sangue , Pulmão/metabolismo , Lesão Pulmonar/sangue , Lesão Pulmonar/etiologia , Masculino , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
16.
Sensors (Basel) ; 19(8)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31027234

RESUMO

Single-sideband (SSB) modulation through Hilbert transformation has successfully transmitted data using only half the bandwidth of the traditional scheme for the same amount of contained information. Toward this end, the four single-sideband (4-SSB) approach for high order modulation is a promising approach for the next-generation communications by applying soft-input soft-output (SISO) equalizer algorithms over orthogonal frequency division multiplexing (OFDM). However, OFDM is challenging for realizing the feasible 5G communications, compared to the emerging techniques, e.g., non-orthogonal multiple access (NOMA), orthogonal multiple access (OMA) or multiple-input multiple-output (MIMO). Since the 4-SSB is an orthogonal modulation which was successfully applied over the traditional OFDM, in this article, we propose a novel 4-SSB modulation scheme over OFDM Guard Interval (GI) and massive MIMO. Besides the carrier signal, from the receiver side, we also apply the shadow equalizer algorithm in the uncoded and coded environment using turbo codes to achieve the 4-SSB with high efficiency from low complexity and energy consumption for 5G. The evaluation results validate that our system consumes lower energy due to low complexity gained from same number of iterations without the heavy decoding as of the 4-SSB SISO based on the turbo equalizer. In addition, the 4-SSB over the OFDM GI achieves the best performance among the relevant approaches conducted in 4-SSB. The proposal then acts as a practical communication system designed to solve the inter-symbol interference (ISI) induced by additional Hilbert transform in the wireless environment toward fifth generation (5G), given that turbo code is considered as a potential channel coding scheme for 5G radio specification.

17.
J Vasc Interv Radiol ; 29(9): 1268-1275.e1, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30061060

RESUMO

PURPOSE: To establish the capability of near-infrared fluorescence (NIRF) imaging for the detection of matrix metalloproteinase 2 (MMP-2) activity as a biomarker of vascular remodeling (VR) in arteriovenous fistulae (AVFs) in vivo. MATERIALS AND METHODS: AVFs were created in the right groins of Wistar rats (n = 10), and sham procedures were performed in the contralateral groins. Fistulography via a left common carotid artery approach confirmed stenosis (> 50%) in a subset of animals (n = 5) 4 weeks after AVF creation. After administration of MMP-2-activated NIRF probe, near-infrared imaging was performed in vivo and ex vivo of both the AVF and the sham-treated vessels to measure radiant efficiency of MMP-2-activated NIRF signal over background. Histologic analyses of AVF and sham-treated vessels were performed to measure VR defined as inward growth of the vessel caused by intimal thickening. RESULTS: AVFs demonstrated a significantly higher percentage increase in radiant efficiency over background compared with sham vessels (45.5 ± 56% vs 16.1 ± 17.8%; P = .008). VR in AVFs was associated with increased thickness of neointima staining positively for MMP-2 (161.8 ± 45.5 µm vs 73.2 ± 36.7 µm; P = .01). A significant correlation was observed between MMP-2 activity as measured by relative increase in radiant efficiency for AVFs and thickness of neointima staining positively for MMP-2 (P = .039). CONCLUSIONS: NIRF imaging can detect increased MMP activity in remodeled AVFs compared with contralateral sham vessels. MMP-2-activated NIRF signal correlates with the severity of intimal thickening. These findings suggest NIRF imaging of MMP-2 may be used as a biomarker of the vascular remodeling underlying stenosis.


Assuntos
Derivação Arteriovenosa Cirúrgica/métodos , Artéria Femoral/diagnóstico por imagem , Veia Femoral/diagnóstico por imagem , Oclusão de Enxerto Vascular/diagnóstico por imagem , Virilha/irrigação sanguínea , Metaloproteinase 2 da Matriz/metabolismo , Imagem Óptica/métodos , Espectroscopia de Luz Próxima ao Infravermelho , Remodelação Vascular , Animais , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Biomarcadores/metabolismo , Artéria Femoral/enzimologia , Artéria Femoral/fisiopatologia , Artéria Femoral/cirurgia , Veia Femoral/enzimologia , Veia Femoral/fisiopatologia , Veia Femoral/cirurgia , Corantes Fluorescentes/administração & dosagem , Oclusão de Enxerto Vascular/enzimologia , Oclusão de Enxerto Vascular/fisiopatologia , Modelos Animais , Neointima , Valor Preditivo dos Testes , Ratos Wistar , Diálise Renal
18.
J Vasc Interv Radiol ; 27(6): 905-12, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27103145

RESUMO

PURPOSE: To characterize thermal changes induced by rheolytic thrombectomy (RT) within an ex vivo venous model and evaluate resultant changes of endothelial and vessel wall injury. MATERIALS AND METHODS: Patent human saphenous vein segments without thrombus were mounted in an ex vivo perfusion system with a temperature probe apposed to the adventitial surface. RT was performed over a guide wire to facilitate device centering. Continuous RT was performed for 4 minutes with temperature recorded every 10 seconds. Pulsed RT was performed for eight cycles of 30 seconds followed by 10 seconds of deactivation. Mean temperature increase, maximum temperature (Tmax), intimal/medial thickness, endothelial cell staining (CD31), and heat shock protein 90 (HSP90) expression were compared between untreated and RT-treated venous segments. RESULTS: Continuous RT produced a mean 7.6°C increase in temperature above baseline with mean Tmax of 44.1°C. Pulsed RT produced a mean 7.3°C increase in temperature and mean Tmax of 43.8°C. Differences in mean temperature increase (P = .66) and Tmax (P = .71) between the two groups were not statistically significant. RT-treated segments showed intima/media thinning (0.32 mm before RT and 0.18 mm after RT; P = .004) and reduction in intact endothelium (38.8% before RT and 13.8% after RT; P = .002). Staining for HSP90 showed a 3.1% increase in expression after RT (P = .31). CONCLUSIONS: RT in this venous model showed reproducible increases in vessel temperature and evidence of endothelial and vessel wall injury. Avoiding prolonged RT application to a focal vascular segment during clinical use may be beneficial.


Assuntos
Endotélio Vascular/cirurgia , Veia Safena/cirurgia , Temperatura , Trombectomia/métodos , Endotélio Vascular/lesões , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Técnicas In Vitro , Perfusão , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Veia Safena/lesões , Veia Safena/metabolismo , Veia Safena/patologia , Trombectomia/efeitos adversos , Fatores de Tempo , Lesões do Sistema Vascular/etiologia , Lesões do Sistema Vascular/metabolismo , Lesões do Sistema Vascular/patologia
19.
Eur J Med Res ; 29(1): 96, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38297403

RESUMO

AIM: The aim of this study was to evaluate the effect of local betamethasone injection into the pterygomandibular space on postoperative neurosensory deficits. MATERIALS AND METHODS: A prospective controlled clinical study was conducted on 16 patients (6 male, 10 female; mean age, 24.95 ± 9.22 years) who underwent bilateral sagittal ramus osteotomy for mandibular discrepancies. One side of each patient's mandible was randomly selected as the control side, and the opposite side as the experimental side. On the experimental side, a solution of betamethasone (6 mg/1 ml) was injected into the pterygomandibular space after the completion of wound closure. Neurosensory tests, including light touch, two-point discrimination, direction of movement, thermal sensitivity, and pin-prick discrimination, were performed. The follow-up period ranged between 6 and 12 months, according to the particular sensory test. The Fisher exact test was used to analyse the data. RESULTS: The light touch sensation was abnormal in 75% of the control side and 31% of the study side, with the difference being significant (p = 0.03). However, at 6 months, all the study cases regained touch sensation, compared to 69% of the control side. No significant difference in direction movement discrimination was seen; however, at 3 months, the study side showed significantly less direction sensation (19%) compared to the control side (56%) (p = 0.02). There was no significant difference in the two-point discrimination; however, at 3 months, the study side had a significantly less abnormal two-point sensation (13%) than the control side (56%) (p = 0.02). In addition, no significant difference was noted in thermal sensitivity or pin-prick sensation. CONCLUSION: Betamethasone injection into the pterygomandibular space reduces neurosensory disturbances after bilateral sagittal split ramus osteotomies nd leads to faster recovery of sensations.


Assuntos
Mandíbula , Osteotomia Sagital do Ramo Mandibular , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Mandíbula/cirurgia , Osteotomia Sagital do Ramo Mandibular/efeitos adversos , Projetos Piloto , Estudos Prospectivos
20.
ACS Omega ; 9(18): 19824-19836, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38737037

RESUMO

Inorganic cubic rubidium-lead-halide perovskites have attracted considerable attention owing to their structural, electronic, and unique optical properties. In this study, novel rubidium-lead-bromide (RbPbBr3)-based hybrid perovskite solar cells (HPSCs) with several high-band-gap chalcogenide electron transport layers (ETLs) of In2S3, WS2, and SnS2 were studied by density functional theory (DFT) and using the SCAPS-1D simulator. Initially, the band gap and optical performance were computed using DFT, and these results were utilized for the first time in the SCAPS-1D simulator. Furthermore, the impact of different major influencing parameters, that is, the thickness of the layer, bulk defect density, doping concentration, and defect density of interfaces, including the working temperature, were also investigated and unveiled. Further, a study on an optimized device with the most potential ETL (SnS2) layer was performed systematically. Finally, a comparative study of different reported heterostructures was performed to explore the benchmark of the most recent efficient RbPbBr3-based photovoltaics. The highest power conversion efficiency (PCE) was 29.75% for the SnS2 ETL with Voc of 0.9789 V, Jsc of 34.57863 mA cm-2, and fill factor (FF) of 87.91%, while the PCEs of 21.15 and 24.57% were obtained for In2S3 and WS2 ETLs, respectively. The electron-hole generation, recombination rates, and quantum efficiency (QE) characteristics were also investigated in detail. Thus, the SnS2 ETL shows strong potential for use in RbPbBr3-based hybrid perovskite high-performance photovoltaic devices.

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