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1.
Small ; : e2401589, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38567494

RESUMO

Despite possessing substantial benefits of enhanced safety and cost-effectiveness, the aqueous zinc ion batteries (AZIBs) still suffers with the critical challenges induced by inherent instability of Zn metal in aqueous electrolytes. Zn dendrites, surface passivation, and corrosion are some of the key challenges governed by water-driven side reactions in Zn anodes. Herein, a highly reversible Zn anode is demonstrated via interfacial engineering of Zn/electrolyte driven by amino acid D-Phenylalanine (DPA) additions. The preferential adsorption of DPA and the development of compact SEI on the Zn anode suppressed the side reactions, leading to controlled and uniform Zn deposition. As a result, DPA added aqueous electrolyte stabilized Zn anode under severe test environments of 20.0 mA cm-2 and 10.0 mAh cm-2 along with an average plating/stripping Coulombic efficiency of 99.37%. Under multiple testing conditions, the DPA-incorporated electrolyte outperforms the control group electrolyte, revealing the critical additive impact on Zn anode stability. This study advances interfacial engineering through versatile electrolyte additive(s) toward development of stable Zn anode, which may lead to its practical implementation in aqueous rechargeable zinc batteries.

2.
Sensors (Basel) ; 22(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36433612

RESUMO

Road pavement condition assessment is essential for maintenance, asset management, and budgeting for pavement infrastructure. Countries allocate a substantial annual budget to maintain and improve local, regional, and national highways. Pavement condition is assessed by measuring several pavement characteristics such as roughness, surface skid resistance, pavement strength, deflection, and visual surface distresses. Visual inspection identifies and quantifies surface distresses, and the condition is assessed using standard rating scales. This paper critically analyzes the research trends in the academic literature, professional practices and current commercial solutions for surface condition ratings by civil authorities. We observe that various surface condition rating systems exist, and each uses its own defined subset of pavement characteristics to evaluate pavement conditions. It is noted that automated visual sensing systems using intelligent algorithms can help reduce the cost and time required for assessing the condition of pavement infrastructure, especially for local and regional road networks. However, environmental factors, pavement types, and image collection devices are significant in this domain and lead to challenging variations. Commercial solutions for automatic pavement assessment with certain limitations exist. The topic is also a focus of academic research. More recently, academic research has pivoted toward deep learning, given that image data is now available in some form. However, research to automate pavement distress assessment often focuses on the regional pavement condition assessment standard that a country or state follows. We observe that the criteria a region adopts to make the evaluation depends on factors such as pavement construction type, type of road network in the area, flow and traffic, environmental conditions, and region's economic situation. We summarized a list of publicly available datasets for distress detection and pavement condition assessment. We listed approaches focusing on crack segmentation and methods concentrating on distress detection and identification using object detection and classification. We segregated the recent academic literature in terms of the camera's view and the dataset used, the year and country in which the work was published, the F1 score, and the architecture type. It is observed that the literature tends to focus more on distress identification ("presence/absence" detection) but less on distress quantification, which is essential for developing approaches for automated pavement rating.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador
3.
Curr Opin Gastroenterol ; 36(1): 19-24, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31688336

RESUMO

PURPOSE OF REVIEW: Anal fissures are very common. They are easy to diagnose and treat in the office setting. They may coexist with hemorrhoids. In fact 20% of patients with hemorrhoids have anal fissures also. The purpose of this review is to highlight current diagnosis and treatment of anal fissures using diet, ointments and botulinum toxin to enable healing. Medical treatment relies on reducing anal sphincter spasm to allow improved blood flow and healing. RECENT FINDINGS: Many anorectal disorders can be managed in the office. Most anal fissures can be managed without the need for surgery. The need for anorectal examination, including use of anoscopy is stressed in the current literature. The use of calcium channel blockers in preference to nitroglycerin is highlighted as well as the use of botulinum toxin when ointments don't work. SUMMARY: Anal fissure can be managed nonsurgically most of the time and gastroenterologists should be able to manage them. This article should help in preventing unnecessary surgery and its complications, mainly incontinence in a small but significant number. The search for more effective drugs and options for managing this disorder continues.


Assuntos
Fissura Anal/terapia , Canal Anal/irrigação sanguínea , Fissura Anal/diagnóstico , Fissura Anal/etiologia , Fissura Anal/fisiopatologia , Gastroenterologia , Humanos , Cicatrização
6.
J Virol ; 90(1): 43-56, 2016 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26446608

RESUMO

UNLABELLED: Human gastrointestinal tract research is limited by the paucity of in vitro intestinal cell models that recapitulate the cellular diversity and complex functions of human physiology and disease pathology. Human intestinal enteroid (HIE) cultures contain multiple intestinal epithelial cell types that comprise the intestinal epithelium (enterocytes and goblet, enteroendocrine, and Paneth cells) and are physiologically active based on responses to agonists. We evaluated these nontransformed, three-dimensional HIE cultures as models for pathogenic infections in the small intestine by examining whether HIEs from different regions of the small intestine from different patients are susceptible to human rotavirus (HRV) infection. Little is known about HRVs, as they generally replicate poorly in transformed cell lines, and host range restriction prevents their replication in many animal models, whereas many animal rotaviruses (ARVs) exhibit a broader host range and replicate in mice. Using HRVs, including the Rotarix RV1 vaccine strain, and ARVs, we evaluated host susceptibility, virus production, and cellular responses of HIEs. HRVs infect at higher rates and grow to higher titers than do ARVs. HRVs infect differentiated enterocytes and enteroendocrine cells, and viroplasms and lipid droplets are induced. Heterogeneity in replication was seen in HIEs from different patients. HRV infection and RV enterotoxin treatment of HIEs caused physiological lumenal expansion detected by time-lapse microscopy, recapitulating one of the hallmarks of rotavirus-induced diarrhea. These results demonstrate that HIEs are a novel pathophysiological model that will allow the study of HRV biology, including host restriction, cell type restriction, and virus-induced fluid secretion. IMPORTANCE: Our research establishes HIEs as nontransformed cell culture models to understand human intestinal physiology and pathophysiology and the epithelial response, including host restriction of gastrointestinal infections such as HRV infection. HRVs remain a major worldwide cause of diarrhea-associated morbidity and mortality in children ≤5 years of age. Current in vitro models of rotavirus infection rely primarily on the use of animal rotaviruses because HRV growth is limited in most transformed cell lines and animal models. We demonstrate that HIEs are novel, cellularly diverse, and physiologically relevant epithelial cell cultures that recapitulate in vivo properties of HRV infection. HIEs will allow the study of HRV biology, including human host-pathogen and live, attenuated vaccine interactions; host and cell type restriction; virus-induced fluid secretion; cell-cell communication within the epithelium; and the epithelial response to infection in cultures from genetically diverse individuals. Finally, drug therapies to prevent/treat diarrheal disease can be tested in these physiologically active cultures.


Assuntos
Intestino Delgado/virologia , Modelos Teóricos , Técnicas de Cultura de Órgãos/métodos , Infecções por Rotavirus/patologia , Infecções por Rotavirus/virologia , Rotavirus/fisiologia , Replicação Viral , Humanos , Intestino Delgado/fisiologia
10.
J Pediatr Gastroenterol Nutr ; 59(1): 57-60, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24509307

RESUMO

We investigated the volume of endoscopic retrograde cholangiopancreatographies (ERCPs) performed in hospitalized children in the United States using a nationwide healthcare administrative database for the years 2000 to 2009. A total of 22,153 cases of ERCP were identified: 6372 diagnostic and 17,314 therapeutic (1533 cases were recorded as undergoing both types during a single hospitalization). The number of ERCPs increased from 5337 to 6733 per year; diagnostic ERCPs decreased 43% and therapeutic increased 69% (significant decreasing trends for diagnostic and increasing for therapeutic ERCPs, P<0.001 for each analysis). Our results define a recent increase in the use of therapeutic ERCPs in hospitalized children.


Assuntos
Doenças Biliares/diagnóstico , Doenças Biliares/terapia , Colangiopancreatografia Retrógrada Endoscópica/estatística & dados numéricos , Colangiopancreatografia Retrógrada Endoscópica/tendências , Pancreatite/diagnóstico , Pancreatite/terapia , Adolescente , Negro ou Afro-Americano/estatística & dados numéricos , Doenças Biliares/epidemiologia , Criança , Pré-Escolar , Bases de Dados Factuais , Feminino , Hispânico ou Latino/estatística & dados numéricos , Hospitalização , Humanos , Lactente , Classificação Internacional de Doenças , Masculino , Pancreatite/epidemiologia , Estados Unidos/epidemiologia , População Branca/estatística & dados numéricos , Adulto Jovem
12.
J Ayub Med Coll Abbottabad ; 26(3): 331-3, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25671940

RESUMO

BACKGROUND: Though the classical type of trigeminal neuralgia is the most common type with the neurovascular conflict causing the symptoms, yet quite some patients have the secondary type of trigeminal neuralgia in which space occupying lesions are responsible for the symptoms. This study was conducted to determine the frequency of cerebellopontine angle tumours in patients presenting with complaints of trigeminal neuralgia. METHODS: This case series descriptive study was conducted in the department of Neurosurgery, Ayub Medical College, Abbottabad, from January 2009 to January 2012. It included patients who presented with symptoms of trigeminal neuralgia. Patients were subjected to further radiological investigation like Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) to look for secondary causes of trigeminal neuralgia. RESULTS: Among the 134 patients with age ranges 13-64 (51?4.3) years of age, 78(58.2%) were females and 56 (41.7%) were males. Frequency of cerebellopontine angle tumours in patients was 14 (10.4%), among them epidermoid was most common lesion being present in 10 (7.4%) of patients and accounted for 75% of Cerebellopontine Angle tumours in these patients. Meningioma and vestibular schwanoma accounted for 2(1.4%) cases each. In secondary trigeminal neuralgia mean age of onset of symptoms was 39.5±5.2 years as compared to classic trigeminal neuralgia which is 53±2.1 years. CONCLUSION: Trigeminal Neuralgia can be a typical symptom in cerebellopontine angle tumours like epidermoid, especially in young patients, so all the patients with trigeminal neuralgia should be investigated for lesion in cerebellopontine region.


Assuntos
Neoplasias Meníngeas/epidemiologia , Meningioma/epidemiologia , Neuroma Acústico/epidemiologia , Neuralgia do Trigêmeo/etiologia , Adolescente , Adulto , Idade de Início , Feminino , Humanos , Masculino , Neoplasias Meníngeas/complicações , Neoplasias Meníngeas/diagnóstico , Meningioma/complicações , Meningioma/diagnóstico , Pessoa de Meia-Idade , Neuroma Acústico/complicações , Neuroma Acústico/diagnóstico , Adulto Jovem
13.
Adv Colloid Interface Sci ; 323: 103068, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38101149

RESUMO

The persistent issue of CO2 emissions and their subsequent impact on the Earth's atmosphere can be effectively addressed through the utilization of efficient photocatalysts. Employing a sustainable carbon cycle via photocatalysis presents a promising technology for simultaneously managing the greenhouse effect and the energy dilemma. However, the efficiency of energy conversion encounters limitations due to inadequate carrier utilization and a deficiency of reactive sites. Single-atom catalysts (SACs) have demonstrated exceptional performance in efficiently addressing the aforementioned challenges. This review article commences with an overview of SAC types, structures, fundamentals, synthesis strategies, and characterizations, providing a logical foundation for the design and properties of SACs based on the correlation between their structure and efficiency. Additionally, we delve into the general mechanism and the role of SACs in photocatalytic CO2 reduction. Furthermore, we furnish a comprehensive survey of the latest advancements in SACs concerning their capacity to enhance efficiency, long-term stability, and selectivity in CO2 reduction. Carbon-structured support materials such as covalent organic frameworks (COFs), graphitic carbon nitride (g-C3N4), metal-organic frameworks (MOFs), covalent triazine frameworks (CTFs), and graphene-based photocatalysts have garnered significant attention due to their substantial surface area, superior conductivity, and chemical stability. These carbon-based materials are frequently chosen as support matrices for anchoring single metal atoms, thereby enhancing catalytic activity and selectivity. The motivation behind this review article lies in evaluating recent developments in photocatalytic CO2 reduction employing SACs supported on carbon substrates. In conclusion, we highlight critical issues associated with SACs, potential prospects in photocatalytic CO2 reduction, and existing challenges. This review article is dedicated to providing a comprehensive and organized compilation of recent research findings on carbon support materials for SACs in photocatalytic CO2 reduction, with a specific focus on materials that are environmentally friendly, readily accessible, cost-effective, and exceptionally efficient. This work offers a critical assessment and serves as a systematic reference for the development of SACs supported on MOFs, COFs, g-C3N4, graphene, and CTFs support materials to enhance photocatalytic CO2 conversion.

15.
Sci Rep ; 13(1): 325, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609678

RESUMO

The global orange industry constantly faces new technical challenges to meet consumer demands for quality fruits. Instead of traditional subjective fruit quality assessment methods, the interest in the horticulture industry has increased in objective, quantitative, and non-destructive assessment methods. Oranges have a thick peel which makes their non-destructive quality assessment challenging. This paper evaluates the potential of short-wave NIR spectroscopy and direct sweetness classification approach for Pakistani cultivars of orange, i.e., Red-Blood, Mosambi, and Succari. The correlation between quality indices, i.e., Brix, titratable acidity (TA), Brix: TA and BrimA (Brix minus acids), sensory assessment of the fruit, and short-wave NIR spectra, is analysed. Mix cultivar oranges are classified as sweet, mixed, and acidic based on short-wave NIR spectra. Short-wave NIR spectral data were obtained using the industry standard F-750 fruit quality meter (310-1100 nm). Reference Brix and TA measurements were taken using standard destructive testing methods. Reference taste labels i.e., sweet, mix, and acidic, were acquired through sensory evaluation of samples. For indirect fruit classification, partial least squares regression models were developed for Brix, TA, Brix: TA, and BrimA estimation with a correlation coefficient of 0.57, 0.73, 0.66, and 0.55, respectively, on independent test data. The ensemble classifier achieved 81.03% accuracy for three classes (sweet, mixed, and acidic) classification on independent test data for direct fruit classification. A good correlation between NIR spectra and sensory assessment is observed as compared to quality indices. A direct classification approach is more suitable for a machine-learning-based orange sweetness classification using NIR spectroscopy than the estimation of quality indices.


Assuntos
Citrus sinensis , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Frutas/química , Análise dos Mínimos Quadrados , Ácidos/análise
16.
J Ayub Med Coll Abbottabad ; 24(2): 39-40, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-24397048

RESUMO

BACKGROUND: Thrombocytopenia is an important cause of mucocutanaeous bleeding in adult and paediatric patients. Immune thrombocytopenia is one of the common causes of thrombocytopenia. Its clinical presentations vary from patient to patient, not studied in our area previously. The present study was planned to see the frequency of clinical presentations of Immune Thrombocytopenic Purpura (ITP) in our patients. METHODS: This prospective study was conducted on 125 patients with ITP, diagnosed by exclusion of secondary causes of thrombocytopenia. Bone marrow examination was performed on all the patients. RESULTS: Bruising, epistaxis and gum bleeding were the commonest clinical presentations in adults and children. Bleeding was more severe in acute cases. Increased menstrual bleeding was seen in female patients. CONCLUSION: Bruising, epistaxis and gum bleeding are the commonest clinical presentations of ITP. Our results are not much different from those of the other studies conducted in Pakistan.


Assuntos
Púrpura Trombocitopênica Idiopática/diagnóstico , Adolescente , Adulto , Criança , Estudos Transversais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão , Estudos Prospectivos
17.
Materials (Basel) ; 15(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35160972

RESUMO

Surface treatments are normally carried out after machining. Surface treatment is a costly and time-consuming process. Hence, it makes sense to reduce the requirement of surface treatment as much as possible. Electrical Discharge Machining (EDM) is a frequently used machining process. EDM produces a recast layer on the surface of machined components. The tribological performance of this recast layer is not very well understood. The properties of the recast layer formed as a result of EDM depend upon the discharge current, electrodes and dielectrics. This work aims to study the effects of each on the tribological performance - in terms of the wear depth, friction coefficient, friction force and contact surface temperature of recast layers. Subsequent improvement in the quality of surfaces will significantly reduce the cost and time required to treat surfaces after machining. Hence, various combinations of discharge current, dielectrics and electrodes have been used to characterize and deduce their effects. The tribo-tests are performed in the boundary lubrication regime under pin-on-disc configuration to analyze sliding friction, contact surface temperature and the wear of the recast layers formed on AISI 304L. The surface morphology of the test pins has been performed by Scanning Electron Microscopy (SEM) before and after the tests. The results show that indeed it is possible to control the tribological performance of the recast layers by varying EDM parameters. This approach promises to be a useful methodology to improve the tribological performance of the layers formed after EDM and reduce the time and costs required for surface treatments post machining.

18.
Plant Signal Behav ; 17(1): 2073420, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-35583149

RESUMO

The changes in plant life behaviors and water status are accompanied by electrophysiological activities. In this study, the theoretical relationship between clamping force (CF) and leaf resistance (R), capacitive reactance (XC), inductive reactance (XL), impedance (Z), and capacitance (C) were exposed as 3-parameter exponential decay and linear models based on bioenergetics, respectively, for mangrove species. The intracellular water metabolism parameters and salt transport characteristics were also determined based on mechanical equations with influences of Sodium nitroprusside (SNP) and rewatering (RW). The results show that the inherent capacitance and effective thickness could better represent Aegiceras corniculatum (A. corniculatum) species, and inherent resistance and impedance show obvious effects on Kandelia obovate (K. obovate) species at different salt levels. SNP application shows positive effect on different salt-resistance capacities of A. corniculatum, while K. obovate perform better in RW phase at high salt level. These outcomes indicates that K. obovate is more salt-resistant because RW process is consistent with actual situation, and response of A. corniculatum at high salt stress is irreversible, even in RW. It is concluded that the electrophysiological parameters could be used for the determination of salt-resistant capacities, which gave more enhanced and reliable information of mangroves' life activities.


Assuntos
Primulaceae , Rhizophoraceae , Nitroprussiato/farmacologia , Primulaceae/fisiologia , Rhizophoraceae/fisiologia , Estresse Salino , Água
19.
J Colloid Interface Sci ; 623: 146-154, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35576646

RESUMO

Iron-nitrogen-carbon (FeNC) catalysts derived from zeolitic-imidazolate frameworks (ZIFs) are worldwide accepted to be the most promising candidates for the oxygen reduction reaction (ORR), but the insufficient stability, the low FeNx exposure and poor density restrict their ORR activity. Here, we demonstrate a strategy to synthesize FeNx sites embedded in a micro/mesoporous N, S co-doped graphitic carbon (FeNC/MUS) by tuning the ligand linkers via the addition of 2-undecylimidazole as a co-ligand in ZIF precursors, and optimizing the electronic structure of Fe center by an in-situ addition of thiourea molecules as sulfur (S) source. 2-undecylimidazole offered an open porous structure to incorporate more FeNx, while the S-doping increased the density of FeNx. Besides, 2-undeclyimidazole cooperatively with S-doping caused favorable changes into the catalyst structure, particularly improved the exposure and density of FeNx sites and doubled the Brunauer-Emmetter-Teller surface area to 1132 m2 g-1 contrasted to the pristine FeNC/M (544 m2 g-1). FeNC/MUS displayed an accelerated ORR activity with a higher half-wave potential of 0.86 V (vs. reversible hydrogen electrode (RHE)) than that of Pt/C (0.84 V) in addition of a longer durability with a 11 % of activity decay after 30000 s in alkaline media. This work offers a new insight to design optimal ZIFs precursor and a facile electron withdrawing S-doping strategy for efficient electrocatalysis.

20.
Chemosphere ; 291(Pt 3): 132987, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34838831

RESUMO

Employing a suitable cocatalyst is very important to improve photocatalytic H2 evolution activity. Herein, two plasmonic cocatalysts, Au nanoparticles and TiN nanoparticles were in-situ coupled over the g-C3N4 nanotube to form a ternary 0D/0D/1D Au/TiN/g-C3N4 composite via a successive thermal polycondensation and chemical reduction method. The g-C3N4 nanotube acted as a support for the growth of Au and TiN nanoparticles, leading to intimate contact between g-C3N4 nanotube with Au nanoparticles and TiN nanoparticles. As a result, multiple interfaces and dual-junctions of Au/g-C3N4 Schottky-junction and TiN/g-C3N4 ohmic-junction were constructed, which helped to promote the charged carriers' separation and enhanced the photocatalytic performance. Furthermore, loading plasmonic cocatalysts of Au nanoparticles and TiN nanoparticles can enhance the light absorption capacity. Consequently, the Au/TiN/g-C3N4 composite exhibited significantly enhanced photocatalytic H2 evolution activity (596 µmol g-1 h-1) compared to g-C3N4 or binary composites of Au/g-C3N4 and TiN/g-C3N4. This work highlights the significant role of cocatalysts in photocatalysis.


Assuntos
Hidrogênio , Nanopartículas Metálicas , Catálise , Ouro , Luz
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