Production of gpsum based foams and pore structure control

Binalardaki ses ve ısı yalıtımı konularında alçıdan yapılmış ürünlere olan talep gün geçtikçe artmaktadır. Bina yangın yönetmeliklerindeki gelişmeler var olan polimer esaslı ürünlerin kullanımına sınırlamalar getirmektedir. Bu amaçla mineral esaslı yalıtım uygulamalarına olan talep artmaktadır. Bu çalışmada, βHemihidrat tipi alçı kullanılmıştır. Gözenek oluşumu için Al2 (SO4 )3 -CaCO3 reaksiyonu tekniği kullanılmıştır. Kullanılan köpük düzenleyici (Kalsiyum stearat) ilave oranının ürünün nihai mekanik ve fiziksel özelliklerine olan etkileri incelenmiştir. Artan köpük düzenleyici miktarı ile gözenek boyutlarının küçüldüğü ancak hacim ağırlığının yükseldiği gözlenmiştir. Küçülen gözenek boyutu nedeniyle ısıl iletkenlik değerlerinde azalma ölçülmüştür. Al2 (SO4 )3 -CaCO3 reaksiyonu tekniği ve kalsiyum stearat ilavesi yüksek kararlılıkta alçı köpükleri üretilmiştir.The demand for products made of plaster on sound and thermal insulation in buildings is increasing day by day. Developments in building fire regulations impose restrictions on the use of existing polymerbased products. Therefore, the demand for the mineral based insulation applications is increasing. In this study, β-hemihydratetype plaster was used. Al2 (SO4 )3 -CaCO3 reaction technique was used for pore formation. The effects of the foam stabilizer (calcium stearat) amount on the final mechanical and physical properties of the product were examined. It was observed that the pore sizes decreased with the increasing amount of foam stabilizer but the bulk density increased. Highly stable gypsum foams were produced by using Al2 (SO4 )3 -CaCO3 reaction technique with the addition of calcium stearate as a foam stabilizer

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

Infected pancreatic necrosis: outcomes and clinical predictors of mortality. A post hoc analysis of the MANCTRA-1 international study

: The identification of high-risk patients in the early stages of infected pancreatic necrosis (IPN) is critical, because it could help the clinicians to adopt more effective management strategies. We conducted a post hoc analysis of the MANCTRA-1 international study to assess the association between clinical risk factors and mortality among adult patients with IPN. Univariable and multivariable logistic regression models were used to identify prognostic factors of mortality. We identified 247 consecutive patients with IPN hospitalised between January 2019 and December 2020. History of uncontrolled arterial hypertension (p = 0.032; 95% CI 1.135-15.882; aOR 4.245), qSOFA (p = 0.005; 95% CI 1.359-5.879; aOR 2.828), renal failure (p = 0.022; 95% CI 1.138-5.442; aOR 2.489), and haemodynamic failure (p = 0.018; 95% CI 1.184-5.978; aOR 2.661), were identified as independent predictors of mortality in IPN patients. Cholangitis (p = 0.003; 95% CI 1.598-9.930; aOR 3.983), abdominal compartment syndrome (p = 0.032; 95% CI 1.090-6.967; aOR 2.735), and gastrointestinal/intra-abdominal bleeding (p = 0.009; 95% CI 1.286-5.712; aOR 2.710) were independently associated with the risk of mortality. Upfront open surgical necrosectomy was strongly associated with the risk of mortality (p < 0.001; 95% CI 1.912-7.442; aOR 3.772), whereas endoscopic drainage of pancreatic necrosis (p = 0.018; 95% CI 0.138-0.834; aOR 0.339) and enteral nutrition (p = 0.003; 95% CI 0.143-0.716; aOR 0.320) were found as protective factors. Organ failure, acute cholangitis, and upfront open surgical necrosectomy were the most significant predictors of mortality. Our study confirmed that, even in a subgroup of particularly ill patients such as those with IPN, upfront open surgery should be avoided as much as possible. Study protocol registered in ClinicalTrials.Gov (I.D. Number NCT04747990)

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population

Timing of Cholecystectomy After Moderate and Severe Acute Biliary Pancreatitis

IMPORTANCE Considering the lack of equipoise regarding the timing of cholecystectomy in patients with moderately severe and severe acute biliary pancreatitis (ABP), it is critical to assess this issue.OBJECTIVE To assess the outcomes of early cholecystectomy (EC) in patients with moderately severe and severe ABP.DESIGN, SETTINGS, AND PARTICIPANTS This cohort study retrospectively analyzed real-life data from the MANCTRA-1 (Compliance With Evidence-Based Clinical Guidelines in the Management of Acute Biliary Pancreatitis) data set, assessing 5304 consecutive patients hospitalized between January 1, 2019, and December 31, 2020, for ABP from 42 countries. A total of 3696 patients who were hospitalized for ABP and underwent cholecystectomy were included in the analysis; of these, 1202 underwent EC, defined as a cholecystectomy performed within 14 days of admission. Univariable and multivariable logistic regression models were used to identify prognostic factors of mortality and morbidity. Data analysis was performed from January to February 2023.MAIN OUTCOMES Mortality and morbidity after EC.RESULTS Of the 3696 patients (mean [SD] age, 58.5 [17.8] years; 1907 [51.5%] female) included in the analysis, 1202 (32.5%) underwent EC and 2494 (67.5%) underwent delayed cholecystectomy (DC). Overall, EC presented an increased risk of postoperative mortality (1.4% vs 0.1%, P <.001) and morbidity (7.7% vs 3.7%, P < .001) compared with DC. On the multivariable analysis, moderately severe and severe ABP were associated with increased mortality (odds ratio [OR], 361.46; 95% CI, 2.28-57 212.31; P = .02) and morbidity (OR, 2.64; 95% CI, 1.35-5.19; P = .005). In patients with moderately severe and severe ABP (n = 108), EC was associated with an increased risk of mortality (16 [15.6%] vs 0 [0%], P < .001), morbidity (30 [30.3%] vs 57 [5.5%], P < .001), bile leakage (2 [2.4%] vs 4 [0.4%], P = .02), and infections (12 [14.6%] vs 4 [0.4%], P < .001) compared with patients with mild ABP who underwent EC. In patients with moderately severe and severe ABP (n = 108), EC was associated with higher mortality (16 [15.6%] vs 2 [1.2%], P < .001), morbidity (30 [30.3%] vs 17 [10.3%], P < .001), and infections (12 [14.6%] vs 2 [1.3%], P < .001) compared with patients with moderately severe and severe ABP who underwent DC. On the multivariable analysis, the patient's age (OR, 1.12; 95% CI, 1.02-1.36; P = .03) and American Society of Anesthesiologists score (OR, 5.91; 95% CI, 1.06-32.78; P = .04) were associated with mortality; severe complications of ABP were associated with increased mortality (OR, 50.04; 95% CI, 2.37-1058.01; P = .01) and morbidity (OR, 33.64; 95% CI, 3.19-354.73; P = .003).CONCLUSIONS AND RELEVANCE This cohort study's findings suggest that EC should be considered carefully in patients with moderately severe and severe ABP, as it was associated with increased postoperative mortality and morbidity. However, older and more fragile patients manifesting severe complications related to ABP should most likely not be considered for EC