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1.
Chem Rev ; 124(4): 1992-2079, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38335114

RESUMEN

Twisted van der Waals (vdW) quantum materials have emerged as a rapidly developing field of two-dimensional (2D) semiconductors. These materials establish a new central research area and provide a promising platform for studying quantum phenomena and investigating the engineering of novel optoelectronic properties such as single photon emission, nonlinear optical response, magnon physics, and topological superconductivity. These captivating electronic and optical properties result from, and can be tailored by, the interlayer coupling using moiré patterns formed by vertically stacking atomic layers with controlled angle misorientation or lattice mismatch. Their outstanding properties and the high degree of tunability position them as compelling building blocks for both compact quantum-enabled devices and classical optoelectronics. This paper offers a comprehensive review of recent advancements in the understanding and manipulation of twisted van der Waals structures and presents a survey of the state-of-the-art research on moiré superlattices, encompassing interdisciplinary interests. It delves into fundamental theories, synthesis and fabrication, and visualization techniques, and the wide range of novel physical phenomena exhibited by these structures, with a focus on their potential for practical device integration in applications ranging from quantum information to biosensors, and including classical optoelectronics such as modulators, light emitting diodes, lasers, and photodetectors. It highlights the unique ability of moiré superlattices to connect multiple disciplines, covering chemistry, electronics, optics, photonics, magnetism, topological and quantum physics. This comprehensive review provides a valuable resource for researchers interested in moiré superlattices, shedding light on their fundamental characteristics and their potential for transformative applications in various fields.

2.
Mod Pathol ; 37(3): 100416, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38154653

RESUMEN

In recent years, artificial intelligence (AI) has demonstrated exceptional performance in mitosis identification and quantification. However, the implementation of AI in clinical practice needs to be evaluated against the existing methods. This study is aimed at assessing the optimal method of using AI-based mitotic figure scoring in breast cancer (BC). We utilized whole slide images from a large cohort of BC with extended follow-up comprising a discovery (n = 1715) and a validation (n = 859) set (Nottingham cohort). The Cancer Genome Atlas of breast invasive carcinoma (TCGA-BRCA) cohort (n = 757) was used as an external test set. Employing automated mitosis detection, the mitotic count was assessed using 3 different methods, the mitotic count per tumor area (MCT; calculated by dividing the number of mitotic figures by the total tumor area), the mitotic index (MI; defined as the average number of mitotic figures per 1000 malignant cells), and the mitotic activity index (MAI; defined as the number of mitotic figures in 3 mm2 area within the mitotic hotspot). These automated metrics were evaluated and compared based on their correlation with the well-established visual scoring method of the Nottingham grading system and Ki67 score, clinicopathologic parameters, and patient outcomes. AI-based mitotic scores derived from the 3 methods (MCT, MI, and MAI) were significantly correlated with the clinicopathologic characteristics and patient survival (P < .001). However, the mitotic counts and the derived cutoffs varied significantly between the 3 methods. Only MAI and MCT were positively correlated with the gold standard visual scoring method used in Nottingham grading system (r = 0.8 and r = 0.7, respectively) and Ki67 scores (r = 0.69 and r = 0.55, respectively), and MAI was the only independent predictor of survival (P < .05) in multivariate Cox regression analysis. For clinical applications, the optimum method of scoring mitosis using AI needs to be considered. MAI can provide reliable and reproducible results and can accurately quantify mitotic figures in BC.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Antígeno Ki-67 , Inteligencia Artificial , Mitosis , Índice Mitótico
3.
J Pak Med Assoc ; 74(7): 1245-1248, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39028048

RESUMEN

Objectives: To compare the outcome of botulinum toxin injection with and without glyceryl trinitrate with respect to postoperative pain and healing in the treatment of anal fissures. METHODS: The prospective, comparative study was conducted at the Department of General Surgery, Mayo Hospital, Lahore, Pakistan, from September 1, 2021, to August 31, 2022, and comprised adult chronic anal fissure patients of either gender. They were randomised using the lottery method into group A which received botulinum toxin injection, and group B which received botulinum toxin injection plus 1g of 0.2% topical glyceryl trinitrate cream. Post-operative pain was measured 24 hours after the procedure using the visual analogue scale. Healing was assessed by examining the wound for the appearance of granulation tissue 4 weeks post-procedure. Data was analysed using SPSS 26. RESULTS: Of the 88 patients, 44(50%) were in group A; 32(72.7%) males and 12(27.3%) females with mean age 33.91±14.8 years. There were 44(50%) patients in group B; 35(79.5%) males and 9(20.5%) females with mean age range 36.33±14.9 years. The mean postoperative pain at 24 hours in group A was 4.67±1.16 and it was 3.06±0.65 in group B (p=0.009). In group A, 23(69.7%) patients showed complete healing at 4 weeks compared to 30(90.9%) in group B (p=0.030). CONCLUSIONS: Botulinum toxin injection with glyceryl trinitrate could be considered as first line of treatment for chronic anal fissure in patients who refuse surgery and with previous sphincter surgery.


Asunto(s)
Toxinas Botulínicas Tipo A , Fisura Anal , Nitroglicerina , Dolor Postoperatorio , Cicatrización de Heridas , Humanos , Fisura Anal/tratamiento farmacológico , Fisura Anal/cirugía , Femenino , Masculino , Nitroglicerina/administración & dosificación , Nitroglicerina/uso terapéutico , Adulto , Dolor Postoperatorio/tratamiento farmacológico , Toxinas Botulínicas Tipo A/administración & dosificación , Toxinas Botulínicas Tipo A/uso terapéutico , Persona de Mediana Edad , Enfermedad Crónica , Cicatrización de Heridas/efectos de los fármacos , Estudios Prospectivos , Adulto Joven , Vasodilatadores/administración & dosificación , Vasodilatadores/uso terapéutico , Fármacos Neuromusculares/administración & dosificación , Fármacos Neuromusculares/uso terapéutico , Quimioterapia Combinada , Resultado del Tratamiento , Dimensión del Dolor
4.
Mod Pathol ; 36(10): 100254, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37380057

RESUMEN

Tumor-associated stroma in breast cancer (BC) is complex and exhibits a high degree of heterogeneity. To date, no standardized assessment method has been established. Artificial intelligence (AI) could provide an objective morphologic assessment of tumors and stroma, with the potential to identify new features not discernible by visual microscopy. In this study, we used AI to assess the clinical significance of (1) stroma-to-tumor ratio (S:TR) and (2) the spatial arrangement of stromal cells, tumor cell density, and tumor burden in BC. Whole-slide images of a large cohort (n = 1968) of well-characterized luminal BC cases were examined. Region and cell-level annotation was performed, and supervised deep learning models were applied for automated quantification of tumor and stromal features. S:TR was calculated in terms of surface area and cell count ratio, and the S:TR heterogeneity and spatial distribution were also assessed. Tumor cell density and tumor size were used to estimate tumor burden. Cases were divided into discovery (n = 1027) and test (n = 941) sets for validation of the findings. In the whole cohort, the stroma-to-tumor mean surface area ratio was 0.74, and stromal cell density heterogeneity score was high (0.7/1). BC with high S:TR showed features characteristic of good prognosis and longer patient survival in both the discovery and test sets. Heterogeneous spatial distribution of S:TR areas was predictive of worse outcome. Higher tumor burden was associated with aggressive tumor behavior and shorter survival and was an independent predictor of worse outcome (BC-specific survival; hazard ratio: 1.7, P = .03, 95% CI, 1.04-2.83 and distant metastasis-free survival; hazard ratio: 1.64, P = .04, 95% CI, 1.01-2.62) superior to absolute tumor size. The study concludes that AI provides a tool to assess major and subtle morphologic stromal features in BC with prognostic implications. Tumor burden is more prognostically informative than tumor size.

5.
Extremophiles ; 27(2): 14, 2023 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-37354217

RESUMEN

Extreme cold environments, such as polar regions or high-altitude mountains, are known for their challenging conditions including low temperatures, high salinity, and limited nutrient availability. Microbes that thrive in these environments have evolved specialized strategies to survive and function under such harsh conditions. The study aims to identify, sequence the genome, perform genome assembly, and conduct a comparative genome-wide analysis of Acinetobacter sp. strain P1, which was isolated from the Batura glacier regions of Pakistan. A basic local alignment search tool of NCBI using 16 s RNA gene sequence confirmed the strain Acinetobacter following phylogenetic analysis revealed that strain P1 clustered with Acinetobacter sp. strain AcBz01. The high-throughput Genome sequencing was done by the NovaSeq 6000 sequencing system following de novo genome assembly reported 23 contigs, a genome size of 3,732,502 bp containing approximately 3489 genes and 63 RNAs (60 tRNA, 3 rRNA). The comparative genome analysis revealed that Acinetobacter sp. strain P1 exhibited the highest homology with the Acinetobacter baumannii ATCC 17978 genome and encompassed 1668 indispensable genes, 1280 conserved genes 1821 specific genes suggesting high genomic plasticity and evolutionary diversity. The genes with functional assignments include exopolysaccharide phosphotransferase enzyme, cold-shock proteins, T6SS, membrane modifications, antibiotic resistance, and set of genes related to a wide range of metabolic characteristics such as exopolysaccharides were also present. Moreover, the structural prediction analysis of EPS proteins reveals that structural flexibility allows for conformational modifications during catalysis, which boosts or increases the catalytic effectiveness at lower temperatures. Overall, the identification of Acinetobacter, a cold-adapted bacterium, offers promising applications in bioremediation, enzyme production, food preservation, pharmaceutical development, and astrobiology. Further research and exploration of these microorganisms can unlock their full biotechnological potential and contribute to various industries and scientific endeavors.


Asunto(s)
Acinetobacter , Acinetobacter/genética , Filogenia , Catálisis , Genómica , Variación Genética , Genoma Bacteriano
6.
An Acad Bras Cienc ; 95(3): e20230014, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37878911

RESUMEN

Microbial proteases are one of the most demanding enzymes for various industries with diverse applications in food, pharmaceutics, and textile industries to name the few. An extracellular alkaline metalloprotease was produced and purified from moderate halophilic bacterial strain, Bacillus cereus TS2, with some unique characteristics required for various industrial applications. The protease was produced in basal medium supplemented with casein and was partially purified by ion exchange chromatography followed by ammonium sulphate precipitation. The alkaline metalloprotease has molecular weight of 35 kDa with specific activity of 535.4 µM/min/mg. It can work at wide range of pH from 3 to 12, while showing optimum activity at pH 10. Similarly, the alkaline metalloprotease is stable till the temperature of 80 °C and works at wide range of temperature from 20 to 90 °C with optimum activity at 60 °C. The turnover rate increases in the presence of NaCl and Co+2 with k cat/KM of 1.42 × 103 and 1.27 × 103 s-1.M-1 respectively, while without NaCl and Co+2 it has a value of 7.58× 102. The alkaline metalloprotease was relatively resistant to thermal and solvent mediated denaturation. Applications revealed that the metalloprotease was efficient to remove hair from goat skin, remove blood stains and degrade milk, thus can be a potential candidate for leather, detergent, and food industry.


Asunto(s)
Bacillus cereus , Cloruro de Sodio , Cloruro de Sodio/farmacología , Metaloproteasas/química , Péptido Hidrolasas , Temperatura , Concentración de Iones de Hidrógeno
7.
Br J Cancer ; 124(6): 1130-1137, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33398064

RESUMEN

BACKGROUND: Diffusion-weighted magnetic resonance imaging (DW-MRI) potentially interrogates site-specific response to neoadjuvant chemotherapy (NAC) in epithelial ovarian cancer (EOC). METHODS: Participants with newly diagnosed EOC due for platinum-based chemotherapy and interval debulking surgery were recruited prospectively in a multicentre study (n = 47 participants). Apparent diffusion coefficient (ADC) and solid tumour volume (up to 10 lesions per participant) were obtained from DW-MRI before and after NAC (including double-baseline for repeatability assessment in n = 19). Anatomically matched lesions were analysed after surgical excision (65 lesions obtained from 25 participants). A trained algorithm determined tumour cell fraction, percentage tumour and percentage necrosis on histology. Whole-lesion post-NAC ADC and pre/post-NAC ADC changes were compared with histological metrics (residual tumour/necrosis) for each tumour site (ovarian, omental, peritoneal, lymph node). RESULTS: Tumour volume reduced at all sites after NAC. ADC increased between pre- and post-NAC measurements. Post-NAC ADC correlated negatively with tumour cell fraction. Pre/post-NAC changes in ADC correlated positively with percentage necrosis. Significant correlations were driven by peritoneal lesions. CONCLUSIONS: Following NAC in EOC, the ADC (measured using DW-MRI) increases differentially at disease sites despite similar tumour shrinkage, making its utility site-specific. After NAC, ADC correlates negatively with tumour cell fraction; change in ADC correlates positively with percentage necrosis. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT01505829.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores/metabolismo , Carcinoma Epitelial de Ovario/patología , Imagen por Resonancia Magnética/métodos , Necrosis , Terapia Neoadyuvante/métodos , Neoplasia Residual/patología , Anciano , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Carcinoma Epitelial de Ovario/metabolismo , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Neoplasia Residual/tratamiento farmacológico , Neoplasia Residual/metabolismo , Pronóstico , Estudios Prospectivos , Carga Tumoral
8.
Anesth Analg ; 133(4): 826-835, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-33857027

RESUMEN

With an estimated worldwide volume of 266 million surgeries in 2015, the call for general inhalation anesthesia is considerable. However, widely used volatile anesthetics such as N2O and the highly fluorinated gases sevoflurane, desflurane, and isoflurane are greenhouse gases, ozone-depleting agents, or both. Because these agents undergo minimal metabolism in the body during clinical use and are primarily (≥95%) eliminated unchanged via exhalation, waste anesthetic gases (WAGs) in operating rooms and postanesthesia care units can pose a challenge for overall elimination and occupational exposure. The chemical properties and global warming impacts of these gases vary, with atmospheric lifetimes of 1-5 years for sevoflurane, 3-6 years for isoflurane, 9-21 years for desflurane, and 114 years for N2O. Additionally, the use of N2O as a carrier gas for the inhalation anesthetics and as a supplement to intravenous (IV) anesthetics further contributes to these impacts. At the same time, unscavenged WAGs can result in chronic occupational exposure of health care workers to potential associated adverse health effects. Few adverse effects associated with WAGs have been documented, however, when workplace exposure limits are implemented. Specific measures that can help reduce occupational exposure and the environmental impact of inhaled anesthetics include efficient ventilation and scavenging systems, regular monitoring of airborne concentrations of waste gases to remain below recommended limits, ensuring that anesthesia equipment is well maintained, avoiding desflurane and N2O if possible, and minimizing fresh gas flow rates (eg, use of low-flow anesthesia). One alternative to volatile anesthetics may be total intravenous anesthesia (TIVA). While TIVA is not associated with the risks of occupational exposure or atmospheric pollution that are inherent to volatile anesthetic gases, clinical considerations should be weighed in the choice of agent. Appropriate procedures for the disposal of IV anesthetics must be followed to minimize any potential for negative environmental effects. Overall, although their contributions are relatively low compared with those of other human-produced substances, inhaled anesthetics are intrinsically potent greenhouse gases and pose a risk to operating-room personnel if not properly managed and scavenged. Factors to reduce waste and minimize the future impact of these substances should be considered.


Asunto(s)
Contaminantes Ocupacionales del Aire/efectos adversos , Anestesia por Inhalación/efectos adversos , Anestésicos por Inhalación/efectos adversos , Calentamiento Global , Efecto Invernadero , Gases de Efecto Invernadero/efectos adversos , Exposición Profesional/efectos adversos , Pérdida de Ozono , Anestésicos por Inhalación/administración & dosificación , Animales , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Humanos , Residuos Sanitarios , Eliminación de Residuos Sanitarios , Exposición Profesional/prevención & control , Salud Laboral , Medición de Riesgo , Factores de Riesgo
9.
Pak J Med Sci ; 37(4): 1118-1121, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34290793

RESUMEN

OBJECTIVE: To assess the role of abdominal binder in patients with midline wound dehiscence after elective or emergency laparotomy in terms of pain, psychological satisfaction and need for reclosure. METHODS: It was a comparative study done at EAST Surgical Ward of Mayo Hospital, Lahore from 1st January 2018 to 31st December 2019. One hundred and sixty-two (162) patients were included in this study with post-operative midline abdominal wound dehiscence and after informed consent by consecutive non probability sampling technique. Patients were divided into two groups by lottery method into eighty-one patients each. Group-A included patients where abdominal binder was applied and Group-B included patients without abdominal binder. In both groups pain score, psychological satisfaction and need for reclosure was assessed and compared. RESULTS: Patients with abdominal binder shows significantly less pain (P value =0.000) and more psychological satisfaction (P value = 0.000) as compared to the patients where abdominal binder was not used. However, there was no difference in reducing the need for reclosure in patients who use abdominal binder (P value = 0.063). CONCLUSION: Although abdominal binder helps in reducing the pain and improving the psychological satisfaction in patients with midline abdominal wound dehiscence yet it doesn't help in healing of wound and reclosure of the dehisced abdominal wound is needed.

10.
Entropy (Basel) ; 21(4)2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33267069

RESUMEN

Modern text hiding is an intelligent programming technique which embeds a secret message/watermark into a cover text message/file in a hidden way to protect confidential information. Recently, text hiding in the form of watermarking and steganography has found broad applications in, for instance, covert communication, copyright protection, content authentication, etc. In contrast to text hiding, text steganalysis is the process and science of identifying whether a given carrier text file/message has hidden information in it, and, if possible, extracting/detecting the embedded hidden information. This paper presents an overview of state of the art of the text hiding area, and provides a comparative analysis of recent techniques, especially those focused on marking structural characteristics of digital text message/file to hide secret bits. Also, we discuss different types of attacks and their effects to highlight the pros and cons of the recently introduced approaches. Finally, we recommend some directions and guidelines for future works.

11.
Anesth Analg ; 134(5): e27, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35427274
12.
J Anesth ; 31(5): 764-778, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28585095

RESUMEN

A large number of studies during the past two decades have demonstrated the efficacy and safety of sevoflurane across patient populations. Clinical researchers have also investigated the effects of sevoflurane, its hemodynamic characteristics, its potential protective effects on several organ systems, and the incidence of delirium and cognitive deficiency. This review examines the clinical profiles of sevoflurane and other anesthetic agents, and focuses upon emerging topics such as organ protection, postoperative cognitive deficiency and delirium, and novel ways to improve postanesthesia outcomes.


Asunto(s)
Anestesia por Inhalación/métodos , Anestésicos por Inhalación/administración & dosificación , Éteres Metílicos/administración & dosificación , Periodo de Recuperación de la Anestesia , Anestésicos por Inhalación/farmacología , Delirio/epidemiología , Hemodinámica/efectos de los fármacos , Humanos , Incidencia , Sevoflurano
13.
Paediatr Anaesth ; 25(8): 764-769, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25989362

RESUMEN

Dr. Theodore W. 'Ted' Striker (1936-), Professor of Anesthesiology and Pediatrics at the University of Cincinnati, has played a pioneering role in the development of pediatric anesthesiology in the United States. As a model educator, clinician, and administrator, he shaped the careers of hundreds of physicians-in-training and imbued them with his core values of honesty, integrity, and responsibility.


Asunto(s)
Anestesiología/historia , Cuidados Críticos/historia , Hospitales Pediátricos/historia , Pediatría/historia , Niño , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Ohio , Médicos
14.
J Pak Med Assoc ; 64(2): 212-3, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24640817

RESUMEN

Factor XIII (FXIII) deficiency is a rare (autosomal recessive) genetic disorder which is associated with delayed bleeding symptoms that occur hour or days after trauma. Spontaneous rupture of visceral organs due to FXIII deficiency is a rare cause of abdominal pain with grave consequences and can be easily confused with other abdominal pathologies because of normal standard coagulation profile in these patients. We report a 15-year-old girl with spontaneous ovarian haemorrhage and splenic haematoma with FXIII deficiency. She had normal coagulation screen along with normal FXIII screen initially on the 5M urea testing which lead to delay in her diagnosis.


Asunto(s)
Deficiencia del Factor XIII/complicaciones , Factor XIII/metabolismo , Hemorragia/etiología , Enfermedades del Ovario/etiología , Adolescente , Diagnóstico Diferencial , Deficiencia del Factor XIII/sangre , Femenino , Hemorragia/diagnóstico , Humanos , Enfermedades del Ovario/sangre , Enfermedades del Ovario/diagnóstico , Tomografía Computarizada por Rayos X
15.
Carbohydr Polym ; 343: 122431, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39174118

RESUMEN

This study reports the development of alginate based hybrid material (Alg/CuO-gC3N4) with copper oxide (CuO) and graphitic carbon nitride (gC3N4). The Alg/CuO-gC3N4 hydrogel bead was prepared by two step process is as follows: formation of CuO-gC3N4 by co-precipitation method and incorporation of CuO-gC3N4 in the calcium alginate (Alg) by ionotropic gelation method. The structural and morphological features of the Alg/CuO-gC3N4 was characterized using different techniques namely Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermogravimetric analysis (TGA), UV Diffuse Reflectance spectroscopy (UV-DRS) and Scanning electron microscopy (SEM). The photocatalytic activity of the Alg/CuO-gC3N4 was extensively evaluated by degrading methylene blue (MB) under UV-vis and sunlight irradiation. The influence of various parameters like pollutant type, initial dye concentration, catalyst dosage, effect of pH, light intensity and reusability was investigated. The Alg/CuO-gC3N4 achieved a maximum degradation efficiency of 86.26 % and 85.15 % for MB at a dye concentration of 1 × 10-5 M under UV-vis and sunlight irradiation respectively, within 60 min using 0.3 wt% of catalyst dosage. The Alg/CuO-gC3N4 exhibited excellent stability and reusability over multiple cycles. Additionally, the incorporation of CuO-gC3N4 in alginate facilitates in reducing the bandgap (2.54 to 2.28 eV) for efficient charge separation, further enhancing the overall photocatalytic activity.

16.
Heliyon ; 10(15): e34804, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39157363

RESUMEN

In the era of global energy crises and the pressing concern of fossil fuel depletion, the quest for sustainable alternatives has become paramount. The current study aims to optimize biodiesel extraction from a combination of waste cooking oil (WCO) and sesame seed oil (SSO) through response surface methodology (RSM) and artificial neural network (ANN). The cold flow properties of biodiesel produced from WCO are a major obstacle to the commercial use of biodiesel. On the other hand, SSO possesses better oxidation stability and cold flow properties. A mixture of waste cooking oil (i.e. 70 % by volume) and sesame seed oil (i.e. 30 % by volume) has been prepared for biodiesel production via a microwave-assisted transesterification process. For biodiesel yield optimization, the interaction among the operating parameters is developed by RSM, whereas biodiesel yield is predicted by ANN. The operating parameters include reaction speed, RPM (100-600 rpm), reaction time (1-5 min), methanol to oil ratio (8:1-12:1 v/v), and catalyst concentration (0.1-2 % w/w). The highest biodiesel yield of 94 % is found at a reaction speed of 350 rpm, reaction time of 3 min, catalyst concentration of 1.05 w/w, and methanol to oil ratio of 10:1. Furthermore, it is discovered that when estimating biodiesel production rate depending on reaction constraints, ANN shows lower comparative error compared to RSM. The results show that ANN outperforms RSM in terms of percentage improvement when it comes to biodiesel production prediction.

17.
Environ Sci Pollut Res Int ; 30(44): 99979-99991, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37624505

RESUMEN

The manufacturing and construction (M&C) sector not only plays a vital role in promoting economic growth, but is also a significant contributor to global air pollution. Growing concerns regarding air pollutant emissions necessitate a more disaggregated (i.e., sectoral) investigation in order to identify the major contributors. This study employs aggregated and disaggregated data to determine the fundamental effects of economic growth (i.e., overall growth and sectoral growth) on air pollutant emissions (APE) (specifically, PM2.5 and PM10 released by the M&C sector) in SAARC economies between 1995 and 2018. It assesses the environmental Kuznets curve (i.e., inverted U-shaped and N-shaped) using the feasible generalized least squares (FGLS), panel-corrected standard errors (PCSE), and generalized method of moments (GMM) techniques. The sectoral analysis reveals the presence of an N-shaped EKC while the overall analysis indicates an inverted U-shaped EKC. Population, financial development (FD), and merchandise exports (MX) have no influence on the estimates. Population and FD increase APE in all models, whereas the effects of MX vary between models. As SAARC economies are capital-deficient, these economies can adopt unbalanced environmental protection policies. First, focus on major contributing sectors (e.g., M&C sector) to curb APE, then focus on less emitting sectors in turn. By implementing pollution reduction strategies on M&C sector activities, governments may reach their threshold (peak) points earlier than expected. A reduction in APE is impossible without rigorous monitoring and application. Being capital-deficient nations and given the collective nature of the problem, a Transboundary Haze/Pollution agreement is required to solve this issue.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Hominidae , Animales , Contaminantes Atmosféricos/análisis , Desarrollo Económico , Contaminación del Aire/análisis , Contaminación Ambiental , Dióxido de Carbono/análisis
18.
Support Care Cancer ; 20(10): 2633-7, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22733373

RESUMEN

PURPOSE: The purpose of this study is to evaluate the efficacy and safety of intravenous (IV) palonosetron in preventing chemotherapy-induced nausea and vomiting (CINV) in patients with cancer who had incomplete control of CINV during their previous cycle of low emetogenic chemotherapy (LEC). METHODS: Patients with histologically or cytologically confirmed cancer, ≥18 years of age, with a Karnofsky Performance Scale score of ≥50% who had received LEC that induced vomiting and/or at least moderate nausea during their previous treatment cycle received palonosetron 0.25 mg IV 30 min before chemotherapy. Outcomes were recorded in patient diaries over 120 h and at an end-of-study visit on days 6, 7, or 8 after LEC administration. The primary efficacy variable was the complete response rate, defined as no emetic episodes and no rescue medication at 0-24 h (acute post-chemotherapy phase), 24-120 h (delayed phase), and 0-120 h (overall). RESULTS: Complete responses among the intent-to-treat study population (n = 34) were recorded for 88.2 % of patients in the acute phase, 67.6% in the delayed phase, and 67.6% overall. No emetic episodes occurred in 91.2 and 79.4% of patients during the acute and delayed phases, respectively, and no nausea in 73.5 and 52.9%, respectively. Palonosetron was well tolerated; only two patients experienced treatment-related adverse events. CONCLUSIONS: Among the patients with cancer who had a history of CINV with LEC, palonosetron was effective in preventing CINV in both the acute and delayed post-chemotherapy phases, and was well tolerated. Randomized comparative studies in larger populations of patients receiving LEC are needed to confirm these findings.


Asunto(s)
Antieméticos/uso terapéutico , Antineoplásicos/efectos adversos , Isoquinolinas/uso terapéutico , Náusea/prevención & control , Quinuclidinas/uso terapéutico , Terapia Recuperativa , Vómitos/prevención & control , Anciano , Antieméticos/administración & dosificación , Femenino , Humanos , Isoquinolinas/administración & dosificación , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Palonosetrón , Seguridad del Paciente , Proyectos Piloto , Quinuclidinas/administración & dosificación , Resultado del Tratamiento , Vómitos/inducido químicamente
19.
ACS Nano ; 16(9): 13959-13968, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-35980379

RESUMEN

Local strain engineering and structural modification of 2D materials furnish benevolent control over their optoelectronic properties and provide an exciting approach to tune light-matter interaction in layered materials. Application of strain at the nanoscale is typically obtained through permanently deformed nanostructures such as nanowrinkles, which yield large band gap modulation, photoluminescence enhancement, and surface potential. Ultrathin transition metal dichalcogenides (TMDs) have been greatly analyzed for such purposes. Herein, we extend strain-induced nanoengineering to an emerging 2D material, CuInP2S6 (CIPS), and visualize extraordinary control over nonlinear light-matter interaction. Wrinkle nanostructures exhibit ∼160-fold enhancement in second harmonic generation (SHG) compared to unstrained regions, which is additionally influenced by a change in the dielectric environment. The SHG enhancement was significantly modulated by the percentage of applied strain which was numerically estimated. Furthermore, polarization-dependent SHG revealed quenching and enhancement in the parallel and perpendicular directions, respectively, due to the direction of the compressive vector. Our work provides an important advancement in controlling optoelectronic properties beyond TMDs for imminent applications in flexible electronics.

20.
Turk J Chem ; 46(2): 302-310, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-38143473

RESUMEN

Tocopherols and tocotrienols in the combined form are known as tocols. Changes of total and individual tocols and sterols concentration of canola oil and deodorizer distillate (DD) during different processing stages were evaluated with the application of gas chromatography (GC) and high-performance liquid chromatography (HPLC). For sterols analysis, GC coupled with flame ionization detector (FID) was used while tocols in canola oil samples and DD, normal phase (NP) HPLC was applied. The results of the present study indicated that levels of total and individual tocols and sterols content were decreased during processing (neutralization to deodorization). Deodorization was found to be the most effective process for the reduction of total sterols and tocols as 55.9% and 34.2%, respectively. A high amount of tocols and sterols was observed in DD. Among tocols and sterols; beta tocopherol (ß-T) and ß-sitosterol were found to be in greater concentration 53.97% and 31.82%, respectively. Therefore, DD could be used as a valuable by-product in the cosmetics and food industries.

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