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1.
ChemSusChem ; : e202301866, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568784

RESUMO

Lithium-ion batteries are commonly used for energy storage due to their long lifespan and high energy density, but the use of unsafe electrolytes poses significant health and safety concerns. An alternative source is necessary to maintain electrochemical efficacy. This research demonstrates new safe glyme-based electrolytes for silica/carbon (SiOx/C) nanocomposite derived from Australian rice husk (RH). The quality of SiOx/C was preserved by using deep eutectic solvent-based pre-treatment and single-step carbonization, which was confirmed through the X-ray analysis of the crystalline phase of silica. The electrochemical assessment of SiOx/C anode using various glyme-based electrolytes for LIBs was carried out. Among them, the resultant half cells based on diglyme electrolyte is superior to others with the first discharge capacity at 1274 mAh/g and a reversible discharge capacity of 759.7 mAh/g. Ex-situ SEM and Time-of-Flight Secondary Ion Mass Spectrometry (ToF- SIMS) analysis of the electrode indicated that diglyme not only improves the capacity but also sustains the electrode architecture for longer cycle life with more LiF-based components and also showed the absence of HF components. Importantly, the addition of fluoroethylene carbonate (FEC) additive enhanced the cycling stability. These results provide a new perspective on developing advanced SiOx/C anode using glyme electrolytes for Li-ion batteries.

2.
Int J Gen Med ; 16: 1695-1703, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37187590

RESUMO

Purpose: This study was conducted to evaluate the results of conservative management of blunt splenic trauma according to the American Association for the Surgery of Trauma-Organ Injury Scale (AAST-OIS) in 2018 by embolization. Methods: This observational study included 50 patients (42 men and 8 women) with splenic injury who underwent multidetector computed tomography (MDCT) and embolization. Results: According to the 2018 AAST-OIS, 27 cases had higher grades than they did according to the 1994 AAST-OIS. The grades of two cases of grade II increased to grade IV; those of 15 cases of grade III increased to grade IV; and four cases of grade IV increased to grade V. As a result, all patients underwent successful splenic embolization and were stable at discharge. No patients required re-embolization or conversion to splenectomy. The mean hospital stay was 11.8±7 days (range, 6-44 days), with no difference in length of hospital stay among grades of splenic injury (p >0.05). Conclusion: Compared with the AAST-OIS 1994, the AAST-OIS 2018 classification is useful in making embolization decisions, regardless of the degree of blunt splenic injury with vascular lacerations visible on MDCT.

3.
Int Med Case Rep J ; 15: 361-366, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35845223

RESUMO

Lymphangiomas are rare and benign vascular malformations of the lymphatic system. They may arise in any location and at all ages and have variable presentation. These lesions in the intestinal wall are reported very rarely. In the case of colonic lymphangiomas, it is more common in late adulthood and old age, which, in this age group is thought to be associated with local disturbances of lymphatic circulation secondary to inflammation, degeneration, surgical procedure, trauma or radiation. The clinical presentation of colonic lymphangiomas varies from incidental findings on imaging to presenting with acute abdomen. The imaging features are usually multilocular cyst in intramural colon and submucosal mass on endoscopy. However, in the case of symptomatic lesions with atypical image findings, and the fact that the disease is rare, preoperative diagnosis is often difficult. On the other hand, although these cystic tumors do not transform into malignancy, they can be locally invasive or complicated, and often require resection. We report a 53-year-old male who had a cystic lymphangioma of the transverse colon illustrated by imaging modalities and recognized via postoperative histopathological examination.

4.
J Pain Res ; 14: 3421-3428, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34754235

RESUMO

PURPOSE: To evaluate the efficacy of fused three-dimensional T2 sampling perfection with application-optimized contrasts using different flip-angle evolutions (3D-SPACE) and three-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) sequences for detecting neurovascular compression (NVC) in patients presenting with trigeminal neuralgia (TN). METHODS: A prospective study was carried in 33 consecutive patients (m/f: 17/16; mean age, 56.3 ± 10.4 years) with unilateral TN confirmed NVC and consensus by two experienced radiologists on fused 3D-SPACE and 3D-TOF-MRA sequences of 3-tesla (3-T) MRI. All patients underwent microvascular decompression (MVD), using photos and video in surgery as documents compared with MRI. Both the MRI and MVD were reported for three grades (contact, compression, distortion), vessel types (artery or vein), identification of offending vessel, site (juxtapontine, cisternal, and juxtapetrous), and location (cranial, caudal, medial, lateral). Agreement between preoperative MRI visualization and surgical findings was assessed using the kappa (K) statistic. RESULTS: The k-values for the agreement were excellent for the grade of NVC (k=0.82), vessel types (k=0.78), and location of conflict (k=0.74), and good for identification of the offending vessel (0.65) and the site-affected vessel (k=0.69). CONCLUSION: The fused D3-SPACE and 3D-TOF-MRA images are highly effective tools for the evaluation and treatment planning of NVC in TN patients.

5.
Cureus ; 13(7): e16401, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34401210

RESUMO

Peutz-Jeghers syndrome (PJS) is an autosomal dominant inheritance characterized by intestinal hamartomatous polyps and hyperpigmented mucocutaneous macules. Bleeding, bowel obstruction, and intussusception are the most common complications in PJS patients. Individuals are infrequently present for the first time with bowel obstruction secondary to intussusception. Intestinal intussusception presentation is often observed clearly on multidetector computed tomography (MDCT) with characteristic findings, such as "target" and "pseudo-kidney" signs, and sometimes shows the cause of lead-point polyp. A complemental examination is needed to attain more diagnostic symptoms of this disorder, including pigmented spots on the oral cavity and lips, family history with multiple gastrointestinal polyps. Here, we report a case of a 17-year-old male who showed traits of Peutz-Jeghers syndrome. However, the diagnosis was not made until he later developed bowel obstruction caused by an ileo-ileal intussusception manifestation on MDCT and eventually proved in typical hamartoma on postoperative histopathology.

6.
Radiol Case Rep ; 16(9): 2557-2563, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34306287

RESUMO

Isolated gallbladder injuries are very uncommon in blunt abdominal trauma due to its small size. Further, they are well protected by the surrounding liver, omentum, and the rib cage. A case of traumatic gallbladder injury in a 47-year-old man with progressive right hypochondrial pain is presented. The gallbladder injury was caused due to a blunt abdominal trauma after a motor vehicle accident. The patient had a history of chronic alcoholism and narcotics abuse. The patient was also human immunodeficiency virus-positive and was on stable treatment for tuberculosis. A diagnosis of gallbladder contusion with intramural dissection was made after an ultrasound and computed tomography scan. However, the patient refused surgery and thus, an ultrasound-guided percutaneous transhepatic drainage of the gallbladder was performed as a temporary treatment. Subsequently, a successful cholecystectomy was performed. Isolated traumatic gallbladder injury has been reviewed due to the rarity of this condition and the diagnostic challenges it poses.

7.
Cureus ; 13(6): e15555, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34131548

RESUMO

Adenomyomatosis of the gallbladder is a benign condition, usually occurring in middle age, in which the epithelium of the gallbladder proliferates and the gallbladder wall thickens with the presence of Rokitansky-Aschoff sinuses (RAS). The diffuse form is an unusual subtype of adenomyomatosis. Herein, we describe a 17-year-old female who presented with dull and intermittent pain in the right hypochondriac region for more than a month. Ultrasound followed by magnetic resonance imaging showed marked diffuse gallbladder wall thickening. A gross cholecystectomy specimen showed a diffusely enlarged gallbladder. The final diagnosis of gallbladder adenomyomatosis (GA) was confirmed by the histopathologic appearance of muscular and epithelial hyperplasia, contributing to mural thickening with epithelial invaginations forming the pathognomonic intramural diverticula known as the RAS. This case highlights that the diffuse form of GA is uncommon and is often accompanied by chronic inflammation, sometimes requiring differential diagnosis from gallbladder malignancies, especially when there is no image showing a "comet tail" of cholesterol crystals in the wall.

8.
ACS Appl Mater Interfaces ; 12(43): 48518-48525, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33074665

RESUMO

Potassium-ion storage devices are attracting tremendous attention for wide-ranging applications on account of their low cost, fast charge transport in electrolytes, and large working voltage. However, developing cost-effective, high-energy electrodes with excellent structural stability to ensure long-term cycling performance is a major challenge. In this contribution, we have derived two different forms of carbon materials from almond shells using different chemical treatments. For instance, hard carbon (HC) and graphene-like activated carbon (AC) nanosheets are developed by employing simple carbonization and chemical activation routes, respectively. The resultant hard carbon (AS-HC) and activated carbon (AS-AC) exhibit outstanding electrochemical performance as negative and positive electrodes in a potassium-ion battery (KIB), respectively, through their tailor-made surface properties. These promising benefits pave a way to construct a biomass-derived carbon potassium-ion capacitor (KIC) by employing AS-HC as the negative electrode and AS-AC as the positive electrode in a K-based electrolyte. The as-fabricated KIC delivers a reasonable specific energy of 105 Wh/kg and excellent cycling life with negligible capacitance fading over 10 000 cycles. This "waste-to-wealth" approach can promote the development of sustainable KICs at low cost and inspire their use for fast-rate K-based energy storage applications.

9.
Small ; 16(37): e2002806, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32761793

RESUMO

The development of pseudocapacitive materials for energy-oriented applications has stimulated considerable interest in recent years due to their high energy-storing capacity with high power outputs. Nevertheless, the utilization of nanosized active materials in batteries leads to fast redox kinetics due to the improved surface area and short diffusion pathways, which shifts their electrochemical signatures from battery-like to the pseudocapacitive-like behavior. As a result, it becomes challenging to distinguish "pseudocapacitive" and "battery" materials. Such misconceptions have further impacted on the final device configurations. This Review is an earnest effort to clarify the confusion between the battery and pseudocapacitive materials by providing their true meanings and correct performance metrics. A method to distinguish battery-type and pseudocapacitive materials using the electrochemical signatures and quantitative kinetics analysis is outlined. Taking solid-state supercapacitors (SSCs, only polymer gel electrolytes) as an example, the distinction between asymmetric and hybrid supercapacitors is discussed. The state-of-the-art progress in the engineering of active materials is summarized, which will guide for the development of real-pseudocapacitive energy storage systems.

10.
ACS Appl Mater Interfaces ; 9(20): 16967-16976, 2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28467709

RESUMO

We designed, synthesized, and characterized a series of novel electron deficient small molecule nonfullerene acceptors based on 1,8-naphthalimide (NAI) and 9-fluorenone (FN) with different branched alkyl chains using various techniques. These molecules are based on an acceptor-donor-acceptor-donor-acceptor (A1-D-A2-D-A1) molecular design configuration with NAI as the end-capping acceptor (A1), FN as electron-withdrawing central (A2) group, and thiophene ring as a donor (D) unit. These materials are named as NAI-FN-NAI (BO) and NAI-FN-NAI (HD) where BO and HD represent butyloctyl and hexyldecyl alkyl groups, respectively. To further modify energy levels of these materials, we converted the weak electron withdrawing ketonic group (C═O) attached to the FN moiety of NAI-FN-NAI (BO) to a stronger electron withdrawing cyano group (C≡N) to obtain the compound NAI-FCN-NAI (BO) by keeping the same alkyl chain. The optical, electrochemical, and thermal properties of the new acceptors were studied. The materials exhibited higher to medium band gaps, low lowest unoccupied molecular orbital (LUMO) energy levels, and highly thermally stable properties. Organic solar cell devices employing conventional poly(3-hexylthiophene) (P3HT) a donor polymer and the newly designed small molecules as the acceptor were investigated. Among all new materials, organic solar cell devices based on NAI-FN-NAI (BO) as an acceptor exhibit the highest performance with an open circuit voltage (VOC) of 0.88 V, a short-circuit current density (JSC) of 9.1 mAcm-2, a fill factor (FF) of 45%, and an overall power conversion efficiency (PCE) of 3.6%. This is the first report of 9-fluorenone based nonfullerene acceptor with P3HT donor in organic solar cell devices with such a promising performance.

11.
Bioresour Technol ; 157: 22-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24530946

RESUMO

Alginate as biomass feedstock for bioconversion into volatile fatty acids (VFAs) is limited primarily by the low solubility in water or little utilization as microbial substrate and yet unknown about the microbial community structure for acidogenesis. The bacterial community structure was demonstrated the reflected changes in VFAs profiles in the maximized acidogenic process from alginate. Bacteroides- and Clostridium-related microorganisms were suggested to be mainly responsible for the hydrolysis of alginate and VFAs production, respectively. And the bacterial community shifted corresponded to VFAs producing was statistically demonstrated. A number of features discussed in this research can stimulate further interests on bioconversion of alginate into anaerobic biofuels production.


Assuntos
Alginatos/metabolismo , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Ácidos Graxos Voláteis/biossíntese , Bactérias/genética , Sequência de Bases , Eletroforese em Gel de Gradiente Desnaturante , Genes Bacterianos , Ácido Glucurônico/metabolismo , Ácidos Hexurônicos/metabolismo , Filogenia , Análise de Componente Principal , RNA Ribossômico 16S/genética
12.
Bioresour Technol ; 148: 601-4, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24080441

RESUMO

In this study, the response surface methodology (RSM) was applied to determine the optimum fermentative condition of alginate with the respect to the simultaneous effects of alginate concentration and initial pH to maximize the production of total volatile fatty acids (TVFAs) and alcohols. The results showed that the alginate fermentation was significantly affected by initial pH than by alginate concentration and there was no interaction between the two variables. The optimum condition was 6.2g alginate/L and initial pH 7.6 with a maximum TVFAs yield of 37.1%. Acetic acids were the main constituents of the TVFAs mixtures (i.e., 71.9-95.5%), while alcohols (i.e., ethanol, butanol, and propanol) were not detected.


Assuntos
Ácidos/metabolismo , Alginatos/metabolismo , Ácidos Graxos Voláteis/biossíntese , Anaerobiose , Ácido Glucurônico/metabolismo , Ácidos Hexurônicos/metabolismo , Modelos Teóricos
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