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71.
Muhammad Rabeel Sofia Javed Ramsha Khan Muhammad Aftab Akram Shania Rehman Deok-kee Kim Muhammad Farooq Khan 《Materials》2022,15(9)
Herein, we synthesized the zinc oxide (ZnO) thin films (TFs) deposited on glass substrates via spray pyrolysis (SP) to prepare self-cleaning glass. Various process parameters were used to optimize photocatalytic performance. Substrates were coated at room temperature (RT) and 250 °C with a 1 mL or 2 mL ZnO solution while maintaining a distance from the spray gun to the substrate of 20 cm or 30 cm. Several characterization techniques, i.e., XRD, SEM, AFM, and UV–Vis were used to determine the structural, morphological, and optical characteristics of the prepared samples. The wettability of the samples was evaluated using contact angle measurements. As ZnO is hydrophilic in nature, the RT deposited samples showed a hydrophilic character, whereas the ZnO TFs deposited at 250 °C demonstrated a hydrophobic character. The XRD results showed a higher degree of crystallinity for samples deposited on heated substrates. Because of this higher crystallinity, the surface energy decreased, and the contact angle increased. Moreover, by using 2 mL solution, better surface coverage and roughness were obtained for the ZnO TFs. However, by exploiting the distance of the spray to the samples size distribution and surface coverage can be controlled, the samples deposited at 30 mL showed a uniform particle size distribution from 30–40 nm. In addition, the photoactivity of the samples was tested by the degradation of rhodamine B dye. Substrates prepared with a 2 mL solution sprayed at 20 cm showed higher dye degradation than other samples, which can play a vital role in self-cleaning. Hence, by changing the said parameters, the ZnO thin film properties on glass substrates were optimized for self-cleaning diversity. 相似文献
72.
Rena C. Moon Vincent Kirkpatrick Lori Gaskins Andre F. Teixeira Muhammad A. Jawad 《Surgery for obesity and related diseases》2019,15(2):245-252
Background
Biliopancreatic diversion with duodenal switch (DS) is known to be superior in weight loss to other bariatric procedures, but with the disadvantage of increased complication rates. Single-anastomosis duodenal-ileal bypass (SADI-S) is reported to have similar weight loss with lower complication rates compared with traditional DS.Objectives
The aim of this study was to compare weight loss and complication rate between SADI-S and double-anastomosis DS at a single institution.Setting
Academic hospital, United States.Methods
A retrospective chart review was performed on 185 patients who underwent laparoscopic or robot-assisted laparoscopic DS between March 1, 2015 and December 10, 2017. A total of 111 patients had SADI-S, and 74 patients underwent double-anastomosis DS.Results
Baseline patient characteristics were comparable between the 2 groups. The mean preoperative body mass index was 56.3 kg/m2 and 54.4 kg/m2 in SADI-S and double-anastomosis DS patients, respectively. Thirteen (11.7%) and 4 (5.4%) patients were readmitted within 30 days after SADI-S and double-anastomosis DS, respectively (P?=?.16). Percentage of total weight loss was 22.0%, 38.5%, and 44.2% in the SADI-S group and 20.2%, 38.0%, and 48.4% in the double-anastomosis DS group at 6, 12, and 24 months, respectively. The majority of patients had vitamin A and E levels in the normal range. However, 40% to 60% of the patients had low levels of vitamin D after the procedure.Conclusions
SADI-S and double-anastomosis DS are comparable in terms of weight loss and complication rate. However, close nutritional follow-up is warranted for both procedures. 相似文献73.
Muhammad S. Sajid Nikhil Ladwa Lorain Kalra Kristian K. Hutson Krishna K. Singh Mazin Sayegh 《World journal of surgery》2012,36(11):2644-2653
Background
The objective of this study was to analyze systematically the randomized, controlled trials that compared single-incision laparoscopic cholecystectomy (SILC) and conventional laparoscopic cholecystectomy (CLC).Methods
The meta-analysis was conducted according to the Quality of Reporting of Meta-analysis (QUORUM) standards. The included studies were analyzed systematically using the statistical software package RevMan. The summated outcomes were expressed as the risk ratios (RR) for dichotomous variables and standardized mean differences (SMD) for continuous variables.Results
Eleven randomized trials encompassing 858 patients were retrieved from the electronic databases. In the random effects model, postoperative pain, postoperative complications, length of hospital stay, cosmesis score, conversion rate, and time to return to normal activities were statistically comparable between the two cholecystectomy techniques. SILC was associated with a longer operating time [SMD 0.71; 95?% confidence interval (CI) 0.38, 1.05; z?=?4.18; p?<?0.0001) and an increased requirement for additional port insertion (RR 6.54; 95?% CI 2.19, 19.57; z?=?3.36; p?<?0008). However, there was significant heterogeneity among the trials.Conclusions
SILC does not offer any advantage over CLC for treating benign gallbladder disorders. CLC may be used assiduously for this purpose. 相似文献74.
75.
Muhammad S. Sajid MBBS MSc MBA FRCS Kristian Hutson MBBS MRCS Lorain Kalra MBBS MRCS Riccardo Bonomi MBBS FRCS 《Journal of surgical oncology》2012,106(6):783-795
A systematic review of randomised, controlled trials investigating the effectiveness of fibrin glue (FG) in reducing the postoperative seroma and seroma related morbidities following breast and axillary surgery was conducted. FG failed to influence the incidence of postoperative seroma, average volume of seroma, wound infection, complications and length of hospital stay in patients undergoing breast cancer surgery. However, a major multicentre and high quality randomised, controlled trial is required to validate these findings. J. Surg. Oncol. 2012; 106:783–795. © 2012 Wiley Periodicals, Inc. 相似文献
76.
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79.
Muhammad Arif 《Journal of medical systems》2012,36(3):1173-1181
In pattern classification problems, feature extraction is an important step. Quality of features in discriminating different classes plays an important role in pattern classification problems. In real life, pattern classification may require high dimensional feature space and it is impossible to visualize the feature space if the dimension of feature space is greater than four. In this paper, we have proposed a Similarity-Dissimilarity plot which can project high dimensional space to a two dimensional space while retaining important characteristics required to assess the discrimination quality of the features. Similarity-dissimilarity plot can reveal information about the amount of overlap of features of different classes. Separable data points of different classes will also be visible on the plot which can be classified correctly using appropriate classifier. Hence, approximate classification accuracy can be predicted. Moreover, it is possible to know about whom class the misclassified data points will be confused by the classifier. Outlier data points can also be located on the similarity-dissimilarity plot. Various examples of synthetic data are used to highlight important characteristics of the proposed plot. Some real life examples from biomedical data are also used for the analysis. The proposed plot is independent of number of dimensions of the feature space. 相似文献
80.
Vladimir Carli Peter Parzer Camilla Wasserman Birgitta Floderus Alan Apter Judit Balazs Shira Barzilay Julio Bobes Romuald Brunner Paul Corcoran Doina Cosman Padraig Cotter Romain Despalins Nadja Graber Francis Guillemin Christian Haring Jean‐Pierre Kahn Laura Mandelli Dragan Marusic Gergely Mészáros George J. Musa Vita Postuvan Franz Resch Pilar A. Saiz Merike Sisask Airi Varnik Marco Sarchiapone Christina W. Hoven Danuta Wasserman 《Addiction (Abingdon, England)》2012,107(12):2210-2222