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1.
Res Sq ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38659840

RESUMEN

Objectives: Post-discharge patient-reported outcomes from trauma registries can be used to measure trauma care quality. However, studies reflecting the Asian experience are limited. Therefore, we aim to develop a digital trauma registry to prospectively capture patient-reported outcomes (PROs) at one-, three-, six-, and twelve-months post-injury in Pakistan. Methods: We will use a cohort study design to develop a digital trauma registry at two tertiary care facilities (Aga Khan University Hospital & Jinnah Postgraduate Medical Center) in Karachi, Pakistan. The registry will include all admitted adult trauma patients (≥18 years). Data collection will be digital using tablets, with mortality, level of disability, and functional status, quality of life being the outcomes. Telephonic interviews will be conducted with the patients and caregivers for follow-up data collection. Discussion: The high disability burden following accidental trauma imposes a significant burden and cost on individuals and society. Therefore, the trauma registry would fill this gap by capturing post-discharge long-term PROs. It will provide the injured patient's post-discharge situation, challenges, and future directions for incorporating long-term PROs in low-resource settings. Including long-term measures in routine follow-ups will provide insights into physical, social, and policy barriers and help advance injury care research.

2.
Int J Biol Macromol ; 266(Pt 2): 131393, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38582476

RESUMEN

Biocomposites developed using natural fibers serve as a sustainable alternative to synthetic composite materials. However, narrowing the performance gap between synthetic composites and biocomposites requires serious efforts. A promising approach is the modification of natural fibers using various chemical treatments. This paper investigates the potential of tannic acid (TA) treatment as a sustainable approach to enhance mechanical performance and reduce moisture absorption of flax fabric-reinforced biocomposites. The methodology involves the treatment of flax woven fabric with tannic acid, a naturally occurring polyphenolic compound, followed by the fabrication of biocomposite using a green epoxy matrix. The variables studied during treatment are TA concentration and processing time. Characterization of untreated and treated flax fabric and its composites was done using various analytical techniques such as FTIR spectroscopy, moisture absorption and mechanical testing (tensile strength, flexural strength, and impact resistance). FTIR spectroscopy of TA-treated flax confirmed attachment of aromatic rings and carbon double bond formation, thus serving for properties enhancement. The mechanical characterization of composites showed that properties are enhanced up to an optimum limit of concentration and processing time i.e., 1 % concentration and 30 min of processing. Moisture absorption of the TA-treated composite also reduced significantly as compared to untreated composites. These findings contribute towards the advancement in sustainable biocomposites and pave the way for their utilization in various applications.


Asunto(s)
Lino , Polifenoles , Taninos , Resistencia a la Tracción , Textiles , Taninos/química , Lino/química , Espectroscopía Infrarroja por Transformada de Fourier , Fenómenos Mecánicos , Materiales Biocompatibles/química
3.
Trauma Surg Acute Care Open ; 8(1): e001171, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38020857

RESUMEN

Objectives: A diverse set of trauma scoring systems are used globally to predict outcomes and benchmark trauma systems. There is a significant potential benefit of using these scores in low and middle-income countries (LMICs); however, its standardized use based on type of injury is still limited. Our objective is to compare trauma scoring systems between neurotrauma and polytrauma patients to identify the better predictor of mortality in low-resource settings. Methods: Data were extracted from a digital, multicenter trauma registry implemented in South Asia for a secondary analysis. Adult patients (≥18 years) presenting with a traumatic injury from December 2021 to December 2022 were included in this study. Injury Severity Score (ISS), Trauma and Injury Severity Score (TRISS), Revised Trauma Score (RTS), Mechanism/GCS/Age/Pressure score and GCS/Age/Pressure score were calculated for each patient to predict in-hospital mortality. We used receiver operating characteristic curves to derive sensitivity, specificity and area under the curve (AUC) for each score, including Glasgow Coma Scale (GCS). Results: The mean age of 2007 patients included in this study was 41.2±17.8 years, with 49.1% patients presenting with neurotrauma. The overall in-hospital mortality rate was 17.2%. GCS and RTS proved to be the best predictors of in-hospital mortality for neurotrauma (AUC: 0.885 and 0.874, respectively), while TRISS and ISS were better predictors for polytrauma patients (AUC: 0.729 and 0.722, respectively). Conclusion: Trauma scoring systems show differing predictability for in-hospital mortality depending on the type of trauma. Therefore, it is vital to take into account the region of body injury for provision of quality trauma care. Furthermore, context-specific and injury-specific use of these scores in LMICs can enable strengthening of their trauma systems. Level of evidence: Level III.

7.
Environ Res ; 206: 112280, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-34756916

RESUMEN

Rapid industrialization is causing a serious threat for the environment. Therefore, this research was aimed in developing ceramic cobalt ferrite (CoFe2O4) nanocomposite photocatalyst coated with coal fly ash (CFA-CoFe2O4) using facile hydrothermal synthesis route and their applications against methylene blue. The pristine cobalt ferrite photocatalyst was also prepared, characterized, and applied for efficiency comparison. Prepared photocatalyst were characterized by X-ray diffraction (XRD), fourier transformed infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS). Optical response of catalysts was check using photoluminescence spectroscopy (PL). pH drift method was used for the surface charge characteristics of the material under acidic and basic conditions of solution pH. The photocatalytic degradation potential of all the materials were determined under ultra-violet irradiations. The influencing reaction parameters like pH, catalyst dose, oxidant dose, dye concentration, and irradiation time, were sequentially optimized to obtain best suited conditions. The 99% degradation of 10 ppm methylene blue was achieved within 60 min of reaction time under pH = 5 and 7, catalyst dose = 10 and 12 mg/100 mL, oxidant = 12 mM and 5 mM for cobalt ferrite and CFA-CoFe2O4 photocatalysts, respectively. Afterwards, the radical scavenging experiments were conducted to find out the effective radical scavengers (˙OH, h+, and e-) in photocatalytic degradation process. The kinetic study of the process was done by applying 1st order, 2nd order, and BMG models. Statistical assessment of interaction effect among experimental variables was achieved using response surface methodology (RSM).


Asunto(s)
Azul de Metileno , Nanocompuestos , Catálisis , Carbón Mineral , Ceniza del Carbón , Azul de Metileno/química , Nanocompuestos/química
8.
Polymers (Basel) ; 13(22)2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34833278

RESUMEN

Three-dimensional printing-based additive manufacturing has emerged as a new frontier in materials science, with applications in the production of functionalized polymeric-based hybrid composites for various applications. In this work, a novel conceptual design was conceived in which an AC electric field was integrated into a commercial 3D printer (-based fused filament fabrication (FFF) working principle) to in situ manufacture hybrid composites having aligned ceramic filler particles. For this work, the thermoplastic poly lactic acid (PLA) was used as a polymer matrix while 10 vol% KNLN (K0.485Na0.485Li0.03NbO3) ceramic particles were chosen as a filler material. The degree of alignment of the ceramic powders depended upon print speed, printing temperature and distance between electrodes. At 210 °C and a 1 kV/mm applied electric field, printed samples showed nearly complete alignment of ceramic particles in the PLA matrix. This research shows that incorporating electric field sources into 3D printing processes would result in in situ ceramic particle alignment while preserving the other benefits of 3D printing.

9.
Sci Rep ; 11(1): 5327, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33674680

RESUMEN

In the present study, the effect of concentration of titanium carbide (TiC) particles on the structural, mechanical, and electrochemical properties of Ni-P composite coatings was investigated. Various amounts of TiC particles (0, 0.5, 1.0, 1.5, and 2.0 g L-1) were co-electrodeposited in the Ni-P matrix under optimized conditions and then characterized by employing various techniques. The structural analysis of prepared coatings indicates uniform, compact, and nodular structured coatings without any noticeable defects. Vickers microhardness and nanoindentation results demonstrate the increase in the hardness with an increasing amount of TiC particles attaining its terminal value (593HV100) at the concentration of 1.5 g L-1. Further increase in the concentration of TiC particles results in a decrease in hardness, which can be ascribed to their accumulation in the Ni-P matrix. The electrochemical results indicate the improvement in corrosion protection efficiency of coatings with an increasing amount of TiC particles reaching to ~ 92% at 2.0 g L-1, which can be ascribed to a reduction in the active area of the Ni-P matrix by the presence of inactive ceramic particles. The favorable structural, mechanical, and corrosion protection characteristics of Ni-P-TiC composite coatings suggest their potential applications in many industrial applications.

10.
Cureus ; 12(4): e7658, 2020 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-32411559

RESUMEN

Introduction Emergencies such as appendicitis, peritonitis, road traffic accidents and gunshots require immediate surgical intervention. Patients are first resuscitated at the emergency department and then shifted to the casualty operation theater (COT). COT is a state-of-the-art operation theater that is open 24/7 and ready to deal with any surgical crisis. Once surgery is performed, the patients are admitted to the surgical ward for post-operative care. Jinnah Postgraduate Medical Centre (JPMC) is the largest tertiary care hospital in Karachi. There is very limited data on the cases that are dealt with on regular basis at the COT in JPMC. Here we break the mold and analyze the various aspects of surgical emergencies treated at the COT over the course of last six months. Objectives To evaluate the demographics and mortality rates of emergencies treated at the COT in the last six months. Methods This was a retrospective study, held for six months (July 1st 2019 to December 31st 2019). Data was obtained from the Records and Administration section, Surgical Unit IV (ward 21), Jinnah Postgraduate Medical Centre. Results Three hundred and fifty-five patients were inducted into the study, predominantly male. Majority (71.54%) of the referrals were made from within the city. The mean age of the patients was 48.57 ± 14.92 years. Appendicitis was the most common emergency treated at the COT. The overall mortality rate was 23.94%. Peritonitis and road traffic accidents contributed significantly to the mortality rate. Conclusion Surgical emergencies treated at the COT have a high mortality rate at one week. Prompt recognition, early referrals and intervention can help reduce mortality in the future.

11.
ACS Appl Mater Interfaces ; 12(1): 601-608, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31815424

RESUMEN

Cu-In metallic hybrid is a promising non-noble catalyst for selective electrochemical CO2 reduction (eCO2R) to CO, but the lack of direct assembly with a gas diffusion electrode (GDE) limits the further development of eCO2R to CO with both high Faradaic efficiency (FE) and high current density. In this study, an in situ electrochemical spontaneous precipitation (ESP) method was applied for the first time to prepare GDE-combined Cu-In electrocatalysts. The optimum Cu-In catalyst consists of a nanoscale "core-shell" structure of polycrystalline CuxO covered by the amorphous In(OH)3 interface. Higher than 90% FE of CO production has been achieved. With the synergy of a GDE flow cell and 1 M KOH catholyte, a current density of ∼200 mA cm-2 was reached at -1.17 V (reversible hydrogen electrode), which enabled a CO yield efficiency record of 3.05 mg min-1(CO2/15 mL min-1 with a 2 cm2 electrode). The ratios between CO and H2 produced can be effectively modulated via fine-tuning ESP conditions demonstrating possibility of generating CO or syngas with tuneable ratios. The present study provides a simple approach for constructing novel catalytic interfaces with dual active centers for eCO2R and other emerging electrochemical catalysis research.

12.
Rep Pract Oncol Radiother ; 23(3): 189-198, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29760593

RESUMEN

AIM: The aim of study was to evaluate the dosimetric effect of collimator-rotation on VMAT plan quality, when using limited aperture multileaf collimator of Elekta Beam Modulator™ providing a maximum aperture of 21 cm × 16 cm. BACKGROUND: The increased use of VMAT technique to deliver IMRT from conventional to very specialized treatments present a challenge in plan optimization. In this study VMAT plans were optimized for prostate and head and neck cancers using Elekta Beam-ModulatorTM, whereas previous studies were reported for conventional Linac aperture. MATERIALS AND METHODS: VMAT plans for nine of each prostate and head-and-neck cancer patients were produced using the 6 MV photon beam for Elekta-SynergyS® Linac using Pinnacle3 treatment planning system. Single arc, dual arc and two combined independent-single arcs were optimized for collimator angles (C) 0°, 90° and 0°-90° (0°-90°; i.e. the first-arc was assigned C0° and second-arc was assigned C90°). A treatment plan comparison was performed among C0°, C90° and C(0°-90°) for single-arc dual-arc and two independent-single-arcs VMAT techniques to evaluate the influence of extreme collimator rotations (C0° and 90°) on VMAT plan quality. Plan evaluation criteria included the target coverage, conformity index, homogeneity index and doses to organs at risk. A 'two-sided student t-test' (p ≤ 0.05) was used to determine if there was a significant difference in dose volume indices of plans. RESULTS: For both prostate and head-and-neck, plan quality at collimator angles C0° and C(0°-90°) was clinically acceptable for all VMAT-techniques, except SA for head-and-neck. Poorer target coverage, higher normal tissue doses and significant p-values were observed for collimator angle 90° when compared with C0° and C(0°-90°). CONCLUSIONS: A collimator rotation of 0° provided significantly better target coverage and sparing of organs-at-risk than a collimator rotation of 90° for all VMAT techniques.

13.
PLoS One ; 13(4): e0196079, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29698424

RESUMEN

Poly(3-hydroxybutyrate) (PHB), a biodegradable polymer, can be produced by different microorganisms. The PHB belongs to the family of polyhydroxyalkanoate (PHA) that mostly accumulates as a granule in the cytoplasm of microorganisms to store carbon and energy. In this study, we established an integrated one-pot electromicrobial setup in which carbon dioxide is reduced to formate electrochemically, followed by sequential microbial conversion into PHB, using the two model strains, Methylobacterium extorquens AM1 and Cupriavidus necator H16. This setup allows to investigate the influence of different stress conditions, such as coexisting electrolysis, relatively high salinity, nutrient limitation, and starvation, on the production of PHB. The overall PHB production efficiency was analyzed in reasonably short reaction cycles typically as short as 8 h. As a result, the PHB formation was detected with C. necator H16 as a biocatalyst only when the electrolysis was operated in the same solution. The specificity of the source of PHB production is discussed, such as salinity, electricity, concurrent hydrogen production, and the possible involvement of reactive oxygen species (ROS).


Asunto(s)
Cupriavidus necator/metabolismo , Técnicas Electroquímicas , Hidroxibutiratos/metabolismo , Methylobacterium extorquens/metabolismo , Poliésteres/metabolismo , Dióxido de Carbono/química , Cromatografía de Gases , Electrodos , Electrólisis , Formiatos/química , Hidrógeno/química , Hidrógeno/metabolismo , Hidroxibutiratos/análisis , Nanopartículas del Metal/química , Oxidación-Reducción , Poliésteres/análisis , Especies Reactivas de Oxígeno/química , Especies Reactivas de Oxígeno/metabolismo
14.
Bioresour Technol ; 255: 39-49, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29414171

RESUMEN

A novel framework, integrating dynamic simulation (DS), life cycle assessment (LCA) and techno-economic assessment (TEA) of a bioelectrochemical system (BES), has been developed to study for the first time wastewater treatment by removal of chemical oxygen demand (COD) by oxidation in anode and thereby harvesting electron and proton for carbon dioxide reduction reaction or reuse to produce products in cathode. Increases in initial COD and applied potential increase COD removal and production (in this case formic acid) rates. DS correlations are used in LCA and TEA for holistic performance analyses. The cost of production of HCOOH is €0.015-0.005 g-1 for its production rate of 0.094-0.26 kg yr-1 and a COD removal rate of 0.038-0.106 kg yr-1. The life cycle (LC) benefits by avoiding fossil-based formic acid production (93%) and electricity for wastewater treatment (12%) outweigh LC costs of operation and assemblage of BES (-5%), giving a net 61MJkg-1 HCOOH saving.


Asunto(s)
Análisis de la Demanda Biológica de Oxígeno , Formiatos , Aguas Residuales , Fuentes de Energía Bioeléctrica , Electricidad , Electrodos
15.
RSC Adv ; 8(51): 29179-29188, 2018 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-35548013

RESUMEN

The effects of annealing treatment between 400 °C and 540 °C on crystallization behavior, grain size, electrochemical (EC) and photoelectrochemical (PEC) oxygen evolution reaction (OER) performances of bismuth vanadate (BiVO4) thin films are investigated in this work. The results show that higher temperature leads to larger grain size, improved crystallinity, and better crystal orientation for the BiVO4 thin film electrodes. Under air-mass 1.5 global (AM 1.5) solar light illumination, the BiVO4 thin film prepared at a higher annealing temperature (500-540 °C) shows better PEC OER performance. Also, the OER photocurrent density increased from 0.25 mA cm-2 to 1.27 mA cm-2 and that of the oxidation of sulfite, a hole scavenger, increased from 1.39 to 2.53 mA cm-2 for the samples prepared from 400 °C to 540 °C. Open-circuit photovoltage decay (OCPVD) measurement indicates that BiVO4 samples prepared at the higher annealing temperature have less charge recombination and longer electron lifetime. However, the BiVO4 samples prepared at lower annealing temperature have better EC performance in the absence of light illumination and more electrochemically active surface sites, which are negatively related to electrochemical double-layer capacitance (C dl). C dl was 0.0074 mF cm-2 at 400 °C and it decreased to 0.0006 mF cm-2 at 540 °C. The OER and sulfide oxidation are carefully compared and these show that the efficiency of charge transport in the bulk (η bulk) and on the surface (η surface) of the BiVO4 thin film electrode are improved with the increase in the annealing temperature. The mechanism behind the light-condition-dependent role of the annealing treatment is also discussed.

16.
J Ayub Med Coll Abbottabad ; 29(4): 551-553, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29330975

RESUMEN

BACKGROUND: Emergency inguinal hernia repair remains the commonest operation performed by general surgeons all over the world. The aim of this study was to compare the mean operative time, post-operative pain, wound infection and early recurrence between Desarda's and Darning emergency inguinal hernia repair. METHODS: This is a randomized controlled trial conducted at Jinnah Postgraduate Medical Centre, Karachi. A total of 186 patients of male gender between ages 20-60 years with incarcerated, obstructed and strangulated inguinal hernia were enrolled in the study. Patients with primary and recurrent inguinal hernias were excluded. All patients were randomized to Desarda group (n=93) and Darning group (n=93). RESULTS: Mean operative time in Desarda group was 55.53±6.81 minutes and mean operative time in darning group was 53.06±5.51 minutes (p-value 0.007). Mild to moderate pain was found insignificantly higher in Desarda group 75 (80.6%) as compared to Darning group 66 (71%) (p-value 0.170). Wound infection was found higher in Desarda group 18 (19.4%) as compared to darning group 9 (9.7%) (p-value 0.061). Recurrence was found significantly higher 15 (55.5%) in Darning group as compared to Desarda group 2 (7.4%) (p-value <0.001). CONCLUSIONS: No significant difference was observed in the postoperative pain, wound infection however, significant differences were observed in the mean operative time and recurrence rates.


Asunto(s)
Urgencias Médicas , Hernia Inguinal/cirugía , Herniorrafia/métodos , Mallas Quirúrgicas , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Adulto Joven
17.
Nanoscale ; 8(41): 17782-17787, 2016 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-27761538

RESUMEN

The impact of post-synthesis processing in reduced graphene oxide materials for supercapacitor electrodes has been analyzed. A comparative study of vacuum, freeze and critical point drying was carried out for hydrothermally reduced graphene oxide demonstrating that the optimization of the specific surface area and preservation of the porous network are critical to maximize its supercapacitance performance. As described below, using a supercritical fluid as the drying medium, unprecedented values of the specific surface area (364 m2 g-1) and supercapacitance (441 F g-1) for this class of materials have been achieved.

18.
Chempluschem ; 81(2): 166-171, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31968761

RESUMEN

A well-defined PN3 -Ru pincer complex (5) bearing a redox-active bipyridine ligand with an aminophosphine arm has been established as an effective and stable molecular electrocatalyst for CO2 reduction to CO and HCOOH with negligible formation of H2 in a H2 O/MeCN mixture.

19.
Angew Chem Int Ed Engl ; 54(7): 2146-50, 2015 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-25537315

RESUMEN

The challenge in the electrochemical reduction of aqueous carbon dioxide is in designing a highly selective, energy-efficient, and non-precious-metal electrocatalyst that minimizes the competitive reduction of proton to form hydrogen during aqueous CO2 conversion. A non-noble metal electrocatalyst based on a copper-indium (Cu-In) alloy that selectively converts CO2 to CO with a low overpotential is reported. The electrochemical deposition of In on rough Cu surfaces led to Cu-In alloy surfaces. DFT calculations showed that the In preferentially located on the edge sites rather than on the corner or flat sites and that the d-electron nature of Cu remained almost intact, but adsorption properties of neighboring Cu was perturbed by the presence of In. This preparation of non-noble metal alloy electrodes for the reduction of CO2 provides guidelines for further improving electrocatalysis.

20.
J Coll Physicians Surg Pak ; 20(5): 310-2, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20642922

RESUMEN

OBJECTIVE: To determine the frequency and profile of carcinoma in multi-nodular goiter and solitary thyroid nodule. STUDY DESIGN: Case series. PLACE AND DURATION OF STUDY: Surgical Unit-I, Ward-3 of Jinnah Postgraduate Medical Centre, Karachi, from January 1999 to January 2009. METHODOLOGY: Cases with solitary thyroid nodules and multi-nodular goiter were included. Patients under 12 years of age, cystic benign lesion in solitary thyroid nodules or those multi-nodular goiters which were not causing pressure symptoms, cosmetic problems or sign of malignancy were excluded. In solitary thyroid nodule, hemithyroidectomy was done and if histopathology examination revealed carcinoma thyroid then completion thyroidectomy was done. In multi-nodular goiter sub-total thyroidectomy done. Results were described as frequency percentages and mean. RESULTS: Out of 397 patients of multi-nodular goiter only one patient was found to be papillary carcinoma (0.25%). In 220 patients of solitary thyroid nodules, 93 patients were diagnosed as carcinoma of thyroid (42.27%). Others diagnosed in solitary thyroid nodule were thyroid adenoma, colloid goiter, thyroiditis and multi-nodular goiter. The frequency of papillary carcinoma in 65.95% occuring females of 12-30 years of age and being multifocal in 6.45%, follicular carcinoma in 23.40%, medullary carcinoma in 7.44%, anaplastic carcinoma in 2.12% and lymphoma in 1.01%. Female were predominantly involved and papillary carcinoma was common in 12-30 years of age (71.63%) and follicular was common in 30-40 years of age (68.18%). 6.45% of papillary carcinoma was found to be multifocal in nature. CONCLUSION: Frequency of carcinoma of thyroid is very high in solitary thyroid nodule (42.27%), but markedly low in multinodular goiter. Papillary carcinoma is the most common variety, most of in younger female.


Asunto(s)
Carcinoma/epidemiología , Carcinoma/patología , Bocio Nodular/patología , Nódulo Tiroideo/epidemiología , Nódulo Tiroideo/patología , Adolescente , Adulto , Distribución por Edad , Carcinoma/cirugía , Niño , Estudios de Cohortes , Femenino , Bocio Nodular/complicaciones , Bocio Nodular/cirugía , Humanos , Masculino , Persona de Mediana Edad , Distribución por Sexo , Nódulo Tiroideo/cirugía , Tiroidectomía , Adulto Joven
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