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1.
Chem Asian J ; : e202300926, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38721713

RESUMO

The transition of the global energy market towards an environment-friendly, sustainable society requires a profound transformation from fossil fuel to zero carbon emission fuel. To cope with this goal production of renewable energy is accelerating worldwide. Hydrogen is a clean energy carrier, due to its clean combustion and abundance. Nonetheless, its storage is a critical challenge to its success. Hydrogen must be stored long after being produced and transported to a storage site. Physical hydrogen storage (PHS) is vital among hydrogen storage modes, and its shortcoming needs to overcome for its successful and economic benefits. This review intends to discuss the techniques and applications of physical hydrogen storage in the state of compressed gas, liquefied hydrogen gas, and cold/cryo compressed gas concerning their working principle, chemical and physical properties, influencing factors for physical hydrogen storage, and transportation, economics, and global outlook. In addition, insights of several probable PHS systems are highlighted. The outcomes of this review envisioned that the PHS still necessitates technological advancements despite having remarkable success. The limitation opens the door to further research, which would be helpful for efficient and long-term physical hydrogen storage.

2.
Sci Rep ; 14(1): 8180, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589431

RESUMO

N6-methyladenosine (6 mA) is the most common internal modification in eukaryotic mRNA. Mass spectrometry and site-directed mutagenesis, two of the most common conventional approaches, have been shown to be laborious and challenging. In recent years, there has been a rising interest in analyzing RNA sequences to systematically investigate mutated locations. Using novel methods for feature development, the current work aimed to identify 6 mA locations in RNA sequences. Following the generation of these novel features, they were used to train an ensemble of models using methods such as stacking, boosting, and bagging. The trained ensemble models were assessed using an independent test set and k-fold cross validation. When compared to baseline predictors, the suggested model performed better and showed improved ratings across the board for key measures of accuracy.


Assuntos
Adenosina , RNA , RNA/genética , RNA Mensageiro , Adenosina/genética , Projetos de Pesquisa
3.
J Clin Pathol ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195220

RESUMO

AIMS: Mitogen-activated protein kinase (MAPK) pathway alteration is a major oncogenic driver in paediatric low-grade gliomas (LGG) and some adult gliomas, encompassing BRAF (most common) and non-BRAF alterations. The aim was to determine the frequency, molecular spectrum and clinicopathological features of MAPK-altered gliomas in paediatric and adult patients at our neuropathology site in Kuwait. METHODS: We retrospectively searched the data of molecularly sequenced gliomas between 2018 and 2023 for MAPK alterations, revised the pathology in view of the 2021 WHO classification and evaluated the clinicopathological data for possible correlations. RESULTS: Of 272 gliomas, 40 (15%) harboured a MAPK pathway alteration in 19 paediatric (median 9.6 years; 1.2-17.6) and 21 adult patients (median 37 years; 18.9-89.2), comprising 42% and 9% of paediatric and adult cases, respectively. Pilocytic astrocytoma and glioblastoma were the most frequent diagnoses in children (47%) and adults (43%), respectively. BRAF V600E (n=17, 43%) showed a wide distribution across age groups, locations and pathological diagnoses while KIAA1549::BRAF fusion (n=8, 20%) was spatially and histologically restricted to cerebellar paediatric LGGs. Non-V600E variants and BRAF amplifications accompanied other molecular aberrations in high-grade tumours. Non-BRAF MAPK alterations (n=8) included mutations and gene fusions involving FGFR1, NTRK2, NF1, ROS1 and MYB. Fusions included KANK1::NTRK2, GOPC::ROS1 (both infant hemispheric gliomas), FGFR1::TACC1 (diffuse LGG), MYB::QKI (angiocentric glioma) and BCR::NTRK2 (glioblastoma). Paradoxical H3 K27M/MAPK co-mutations were observed in two LGGs. CONCLUSION: The study provided insights into MAPK-altered gliomas in Kuwait highlighting the differences among paediatric and adult patients and providing a framework for planning therapeutic polices.

4.
Chem Asian J ; : e202300575, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37695836

RESUMO

Hydrogen heralded as a promising renewable and environmentally friendly energy carrier, carries inherent risks owing to its highly flammable nature. A mere 4 % concentration of hydrogen in the air can trigger an explosion. To counteract this peril, a composite material comprising PbOX -ZnO (2 : 1) was synthesized, characterized, and subsequently employed to fabricate a hydrogen sensing device. Various analytical tools were used to characterize as-deposited materials, including X-ray diffraction, Scanning electron microscopy /Energy Dispersive X-ray Spectroscopy, Transmission electron microscopy UV-Vis Reflectance Spectroscopy and Fourier-transform infrared spectroscopy. The device exhibited favorable properties, such as good selectivity, stability, and a low detection limit for hydrogen. At ambient room temperature, the device demonstrated a sensing signal reaching 468.7, with a response time (T90) of 155 seconds and a recovery time (Tr90) of 69 seconds when exposed to a hydrogen concentration of 5 ppm. This performance underscores the device's rapid and effective response to hydrogen exposure. Moreover, the PbOX-ZnO (2 : 1) composite-based device exhibited a detection limit of 2.4 ppm, functioning accurately within a linear range spanning from 5 ppm to 50 ppm. This capability confirms its precision in accurately detecting hydrogen concentrations within this designated range.

5.
Sci Rep ; 13(1): 14289, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37652952

RESUMO

In this study, Nb2CTx MXene reinforced commercially pure magnesium composite was processed using traditional blend-press-sinter technique. The added one volume percentage of Nb2CTx MXene was fairly dispersed around the magnesium particles despite having sporadic clustering. Nb2CTx MXene reinforcement was stable and developed defect free strong interfacial bonding with the magnesium matrix. The small amount of chemically compatible and thermally stable Nb2CTx MXene reinforcement was successful in enhancing the bulk hardness and compressive yield strength, compressive strength, ductility and fracture toughness of the commercially pure magnesium.

6.
J Infect Dev Ctries ; 17(5): 656-664, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37279424

RESUMO

INTRODUCTION: Herpesviruses are a widespread family of double-stranded DNA viruses that establish life-long persistent infection in their hosts. Cumulative evidence tends to argue for the association of human herpesviruses, such as Kaposi's sarcoma herpesvirus (KHSV), Epstein-Barr virus (EBV), and human cytomegalovirus (HCMV) with various human disorders and diseases. The present study aims to investigate the presence of herpesviruses in colorectal cancer (CRC). METHODOLOGY: We investigated the presence of herpesviruses in 69 formalin-fixed paraffin embedded tissue (FFPE) biopsies, using a pan-herpesvirus nested polymerase chain reaction (PCR) with degenerate primers and HCMV specific primers to identify the presence of herpesviruses in CRC tissue. RESULTS: None of the samples we examined were positive for herpesviruses. CONCLUSIONS: Our results suggest that there is no (or very low) prevalence of lifelong herpesvirus infection in Algerian CRC patients. Larger cohorts may provide more insight into the prevalence of herpesviruses in Algerian CRC biopsies.


Assuntos
Neoplasias Colorretais , Infecções por Vírus Epstein-Barr , Infecções por Herpesviridae , Humanos , Herpesvirus Humano 4/genética , Infecções por Herpesviridae/epidemiologia , Citomegalovirus , Neoplasias Colorretais/epidemiologia
7.
PLoS One ; 18(4): e0281601, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37043488

RESUMO

INTRODUCTION: Bilateral risk-reducing mastectomy (BRRM) involves removal of healthy breast tissue to substantially decrease the risk of developing breast cancer in individuals with greater susceptibility due to a strong family history or genetic mutation. This retrospective study evaluates cases of BRRM and associated reconstruction performed at a tertiary centre, with emphasis on mastectomy and reconstructive trends. METHODS: A retrospective review of all BRRM cases performed between January 2010 and May 2022 was conducted, with two separate cohorts corresponding to the earlier (group 1) and later (group 2) portion of the time-period. Data collected included demographics, genetic test results, family history of breast/ovarian cancer, co-morbidities, mastectomy type, reconstruction type, surgical histopathology findings and post-operative complications. RESULTS: A total of 82 patients (group 1 = 41, group 2 = 41) underwent BRRM. The proportion of nipple-sparing mastectomy increased from 14.6% to 56.1% between the two time periods with a reduction in skin-sparing mastectomies from 75.6% to 20.3% (p<0.001). Of the 80 patients who opted to undergo reconstruction, there was a significant decrease in combined flap-implant reconstructions (19.51% to 0%, p<0.01). Importantly, for implant-only reconstruction, there were significant increases in prepectoral approaches (p = 0.0267) and use of acellular dermal matrix (ADM) (48.15% to 90.63%, p<0.001). CONCLUSION: This study documents recent increases in nipple-sparing techniques for BRRM compared to more traditional skin-sparing methods. Concurrently, reconstruction following RRM has become predominantly implant-based without a flap, coinciding with more widespread usage of ADM. This is consistent with national trends towards fewer complex autologous procedures.


Assuntos
Derme Acelular , Implantes de Mama , Neoplasias da Mama , Mamoplastia , Humanos , Feminino , Mastectomia/métodos , Neoplasias da Mama/genética , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Mamoplastia/métodos , Estudos Retrospectivos , Centros de Atenção Terciária , Mamilos/patologia
8.
Sensors (Basel) ; 23(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36850858

RESUMO

Cellular vehicle-to-everything (C-V2X) is one of the enabling vehicular communication technologies gaining momentum from the standardization bodies, industry, and researchers aiming to realize fully autonomous driving and intelligent transportation systems. The 3rd Generation Partnership Project (3GPP) standardization body has actively been developing the standards evolving from 4G-V2X to 5G-V2X providing ultra-reliable low-latency communications and higher throughput to deliver the solutions for advanced C-V2X services. In this survey, we analyze the 3GPP standard documents relevant to V2X communication to present the complete vision of 3GPP-enabled C-V2X. To better equip the readers with knowledge of the topic, we describe the underlying concepts and an overview of the evolution of 3GPP C-V2X standardization. Furthermore, we provide the details of the enabling concepts for V2X support by 3GPP. In this connection, we carry out an exhaustive study of the 3GPP standard documents and provide a logical taxonomy of C-V2X related 3GPP standard documents divided into three categories: 4G, 4G & 5G, and 5G based V2X services. We provide a detailed analysis of these categories discussing the system architecture, network support, key issues, and potential solution approaches supported by the 3GPP. We also highlight the gap and the need for intelligence in the execution of different operations to enable the use-case scenarios of Level-5 autonomous driving. We believe, the paper will equip readers to comprehend the technological standards for the delivery of different ITS services of the higher level of autonomous driving.

9.
J Cancer Educ ; 38(2): 538-544, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35254629

RESUMO

Lung cancer is the leading cause of cancer mortality in the USA. In the rural Black Belt region of Alabama, high rates of lung cancer incidence and mortality coupled with disproportionate lack of access to health services stresses the need for navigating high risk and disproportionately affected groups towards successfully obtaining lung cancer screenings. We utilized our well-accepted Community Health Advisor (CHA) model for education and awareness. This study seeks to evaluate the results of the Alabama Lung Cancer Awareness, Screening, and Education (ALCASE) training on CHAs, program evaluation, and lessons learned. A total of 202 participants were eligible and enrolled for CHA training. One hundred thirty CHAs were included for the final analyses. Descriptive statistics were computed; differences in pre-test and post-test scores were compared across demographic characteristics of the participants using paired t-test/one-way ANOVA. Of the 130 CHAs, 46% were 65 years or older; 98% were African Americans, and 87% were female; 17% of participants were cancer survivors. The mean post-test scores were 2.2 points greater than mean pre-test scores, and the difference was significant (mean (SD): pre-test = 20.8 (2.8) versus post-test = 23 (2.2); p = 0.001). No notable difference in pre-test and post-test scores were observed by CHA's demographic characteristics except by their county of residence or work (p = 0.0019). We demonstrate the capability and value of successfully recruiting and training motivated community members to be able to serve educators to better reach medically underserved and historically excluded communities.


Assuntos
Neoplasias Pulmonares , Saúde Pública , Humanos , Feminino , Masculino , Avaliação de Programas e Projetos de Saúde , Saúde Pública/educação , Currículo , Alabama/epidemiologia , Neoplasias Pulmonares/prevenção & controle , Agentes Comunitários de Saúde/educação
10.
ACS Omega ; 7(50): 45981-45990, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36570221

RESUMO

Photoactive polymer and quantum dots (QDs)/nanocrystals (NCs)-based bulk heterojunction (BHJ) solar cells have the combined positivity of organic semiconductors and inorganic components, which can enable a high carrier mobility and absorption coefficient. Additionally, the NCs also provide the opportunity to tune the band gap to obtain enhanced absorption in a broad solar spectrum. Among the semiconductors, lead chalcogenide NCs are of particular interest due to their good photosensitivity in the near-infrared (NIR) region of the solar spectrum. These NCs have large exciton Bohr radii (18, 46, and 150 nm for PbS, PbSe, and PbTe, respectively) and tunable sizes depending on the optical bandgaps between 0.3 and 1.5 eV. Independently, lead chalcogenide NCs have been studied extensively for different applications; however, uses in polymer-NC-based bulk heterojunction solar cells are limited. This Review has been structured on the lead chalcogenide NCs incorporated in polymer composite-based bulk heterojunction solar cells covering the material, properties, and solar cell performance to find the issues and explore future opportunities.

11.
Appl Water Sci ; 12(8): 185, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754932

RESUMO

The presence of lead compounds in the environment is an issue. In particular, supply water consumption has been reported to be a significant source of human exposure to lead compounds, which can pose an elevated risk to humans. Due to its toxicity, the International Agency for Research on Cancer and the US Environmental Protection Agency (USEPA) have classified lead (Pb) and its compounds as probable human carcinogens. The European Community Directive and World Health Organization have set the maximum acceptable lead limits in tap water as 10 µg/L. The USEPA has a guideline value of 15 µg/L in drinking water. Removal of lead ions from water and wastewater is of great importance from regulatory and health perspectives. To date, several hundred publications have been reported on the removal of lead ions from an aqueous solution. This study reviewed the research findings on the low-cost removal of lead ions using different types of adsorbents. The research achievements to date and the limitations were investigated. Different types of adsorbents were compared with respect to adsorption capacity, removal performances, sorbent dose, optimum pH, temperature, initial concentration, and contact time. The best adsorbents and the scopes of improvements were identified. The adsorption capacity of natural materials, industrial byproducts, agricultural waste, forest waste, and biotechnology-based adsorbents were in the ranges of 0.8-333.3 mg/g, 2.5-524.0 mg/g, 0.7-2079 mg/g, 0.4-769.2 mg/g, and 7.6-526.0 mg/g, respectively. The removal efficiency for these adsorbents was in the range of 13.6-100%. Future research to improve these adsorbents might assist in developing low-cost adsorbents for mass-scale applications.

12.
Chem Rec ; 22(9): e202200107, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35701111

RESUMO

Transition metal dichalcogenides (TMDCs)-based laminar membranes have gained significant interest in energy storage, fuel cell, gas separation, wastewater treatment, and desalination applications due to single layer structure, good functionality, high mechanical strength, and chemical resistivity. Herein, we review the recent efforts and development on TMDCs-based laminar membranes, and focus is given on their fabrication strategies. Further, TMDCs-based laminar membranes for water purification and seawater desalination are discussed in detail. Finally, present their merits, limits and future challenges needed in this area.


Assuntos
Elementos de Transição , Purificação da Água , Água do Mar/química , Elementos de Transição/química , Água
13.
Environ Sci Pollut Res Int ; 29(36): 54432-54447, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35304716

RESUMO

A solid polymer, poly[(sodium methacrylate)-co-2-(methacryloyloxy)ethyl acetoacetate], p(MAA-co-MEAA) was synthesized and then grafted onto carbon nanotubes to prepare poly(MAA-co-MEAA)-grafted carbon nanotubes [CNT-g-p(MAA-co-MEAA)]. NMR, TGA, and FT-IR characterized the synthesized polymers and adsorbents. SEM-EDX was used to investigate the surface characteristics of the adsorbents. Pb2+ was removed from the aqueous solution using the CNT-g-p(MAA-co-MEAA). A batch adsorption experiment was performed at different Pb2+ concentrations (1, 10, 25, 50 mg/L), pH (4 and 6.75), temperature (25 and 35 °C), and contact periods (1, 5, 20, 60, and 1440 min) to study the adsorption kinetics and isotherm. The adsorbent dose of 2.5 g/L could effectively lower the initial Pb2+ concentration of 1000 to 2 ppb. The maximum adsorption capacity of the adsorbent was found to be 1178 mg/g. In addition, the adsorbents have been shown to effectively reduce the coexisting metal ion concentrations from industrial wastewater, which indicated the potential of the proposed adsorbent in removing metal ions from coexisting metals containing wastewater. To predict the adsorption efficiency of Pb2+, various linear, non-linear, and neural network models were established. An additional data set, not incorporated in model training, was used to validate the models. A number of models showed excellent performance with R2 in the range of 0.89-0.98. In model validation studies, the correlation coefficients (r) ranged from 0.94 to 0.99. The novel adsorbent and models will most likely aid in the development of a robust treatment technique for removing Pb2+ ions from water and wastewater.


Assuntos
Nanotubos de Carbono , Poluentes Químicos da Água , Purificação da Água , Acetoacetatos , Adsorção , Concentração de Íons de Hidrogênio , Íons , Cinética , Chumbo , Metacrilatos , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias/química , Água/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos
15.
Chem Rec ; 22(7): e202100330, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35199444

RESUMO

The perovskites solar cells (PSCs) is composed of multifaceted device architecture and involve complex charge extraction (both electronic and ionic), this makes the task demanding to unlock the origin of the different physical process that occurs in a PSC. The capacitance in PSCs depends on several external perturbations including frequency, illumination, temperature, applied bias, and importantly on the interface modification of perovskites/charge selective contact. Arguably, different features including interfacial and bulk; ionic, and electronic charge transport in PSCs occur at different time scales. Capacitance spectroscopy is a prevailing technique to unravel the various physical phenomenon that occurs in a PSC at different time scales. A deeper knowledge of the capacitive response of a PSCs is essential to understand the charge carrier kinetics and unlock the device physics. This work highlights the capacitive response of PSCs and its application to unlock the device physics which is essential for the further optimization and improvement of the device performance.

19.
Int J Neonatal Screen ; 7(3)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34449519

RESUMO

Kuwait is a small Arabian Gulf country with a high rate of consanguinity and where a national newborn screening program was expanded in October 2014 to include a wide range of endocrine and metabolic disorders. A retrospective study conducted between January 2015 and December 2020 revealed a total of 304,086 newborns have been screened in Kuwait. Six newborns were diagnosed with classic homocystinuria with an incidence of 1:50,000, which is not as high as in Qatar but higher than the global incidence. Molecular testing for five of them has revealed three previously reported pathogenic variants in the CBS gene, c.969G>A, p.(Trp323Ter); c.982G>A, p.(Asp328Asn); and the Qatari founder variant c.1006C>T, p.(Arg336Cys). This is the first study to review the screening of newborns in Kuwait for classic homocystinuria, starting with the detection of elevated blood methionine and providing a follow-up strategy for positive results, including plasma total homocysteine and amino acid analyses. Further, we have demonstrated an increase in the specificity of the current newborn screening test for classic homocystinuria by including the methionine to phenylalanine ratio along with the elevated methionine blood levels in first-tier testing. Here, we provide evidence that the newborn screening in Kuwait has led to the early detection of classic homocystinuria cases and enabled the affected individuals to lead active and productive lives.

20.
Front Psychiatry ; 11: 580268, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33093839

RESUMO

BACKGROUND: Bangladesh, a developing country with a lower-middle-income and one of the world's most densely populated areas, has been severely affected by COVID-19. This global epidemic is not only affecting the physical health of the patients but also causing severe psychological effects among those who have not yet been infected. Sleep disturbance is one of the key symptoms of major depression and one of the proven risk factors for suicide. The objective of this study is to identify the risk factors associated with sleep disturbance which has developed as a general impact of COVID-19 and new normal life during the lockdown (a measure to control the spread of COVID-19) in Bangladesh. METHODS: Demographic characteristics, COVID-19, and lockdown related information have been collected from 1,128 individuals by conducting a web-based survey. Respondent's perspective regarding sleep disturbance during COVID-19 lockdown is considered as the outcome of interest which is dichotomous. Descriptive statistics methods have been applied to explore the distribution of respondent's demographic characteristics. Pearson's chi-square tests have been performed to relate the sleep disturbance status of the respondents to their demographic, personal, and COVID-19 related information. Furthermore, a multivariable logistic regression model has been adopted to identify the significant association of sleep disturbance with the demographic, COVID-19, and lockdown related information of respondents during the COVID-19 lockdown in Bangladesh. FINDINGS: The prevalence of sleep disturbance during the COVID-19 lockdown is found to be higher among participants aged 31-40 years. Gender disparity has also been observed in favor of male participants, whereas no significant regional heterogeneity has been found. Working from home or doing online classes during the lockdown has been found as a potential predictive factor of sleep disturbance. Losing a job has been considered as an adverse economic effect of COVID-19, which also induces sleep disturbance. Perception regarding the risk of getting infected and anxiety triggered the chance of developing sleep disturbance. The sleeping schedule is also found as a risk factor for sleep disturbance. CONCLUSION: Evidence-based policies are required to combat psychological challenges that have arisen due to COVID-19, primarily targeting the groups who are largely suffering from sleep disturbance.

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