11 research outputs found
Shielding parameters of leaded cement mortar
The Cathode ray tubes (CRTs) represent more than 70% of global e-waste sets. The glass of the CRT is doped with lead to prevent emission of radiations especially electrons. The glass at the panel and neck of the CRT along with the cement mortar, a mixture of 70% neck glass and 30% cement (mix70), are investigated mathematically as shielding materials from photons having energies in the range 0.06-3 (MeV). Experimentally the material mix70 is tested at energies 0.238 and 0.583 (MeV). Good agreement was recognized between the calculated shielding parameters and that obtained experimentally while complete equality between the calculated parameters carried out using the online XCom software or Phy-X software except at low energies for concrete material. Glass from panel, neck and mix70 have acceptable shielding characteristics at and below the energy 0.238 (MeV) or generally at the X-ray region. Neck glass has good shielding parameters at the chosen energy region and it is nominated as a shielding material for many nuclear applications. To enhance the shielding characteristics of the material mix70 it should be compacted during preparation to get higher density. The present work tested the shielding properties of leaded glass composites to find out its integrity for practical shielding applications and radiological safety
Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications
BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients.
OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs.
DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification.
PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries.
MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes.
RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (VT) size was 500 ml, or 7 to 9 ml kg1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P < 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P < 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure.
CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high VT and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome
Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications: LAS VEGAS - An observational study in 29 countries
BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (V T) size was 500 ml, or 7 to 9 ml kg−1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P ˂ 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P ˂ 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high V T and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome.</p
عن مصايد الجمبري في خليج السويس - مصر
Prawn fisheries in the Gulf of Suez constitute about 13.7% of the total fish and shrimp landings. About 11% are made up by three penaeid species namely: Penaeus japonicus Bate, Penaeus semisulcatus De Han and Penaeus latisulcatus Kishinouy. Metapenaeopsis stridulants Alcock and Trachypenaeus curvirostris Stimpson are two further small species which form only 2.7% of the-total landing of the trawlers in the Gulf.
Percentages of the three large species are 47% for P. japonicus, 30% for P. latisulcatus and 23% for P. semisulcatus. The intensive fishing period takes place from October to May, coinciding with the spawning period of P. semisulcatus (October-March).
The middle of the Northern half of the Gulf is the richest area for the three forms. The monthly catch weight per unit effort showed a general decline from the beginning of each fishing season to January-February. A slight increase occurred afterwards. This may be due to the new arrivals of P. latisulcatus to the fishery ground.
The fishing season 1983-1984 gave a high yield of the large prawns (749 tons) with a fishing effort of 13690 fishing days.يكون الجمبري حوالي 13.7% من محصول الصيد الكلي في خليج السويس وهناك 11% من المصيد من الأنواع الكبيرة بينيس جابونيكس بيت ، بينيس سيمسلكاتس دي هان ، وبينيس لاتيسلكاتس كيشنوي ، والنوعان الصغيران حجماً وهما متيا بنيوبسس ستريديولانتس ألكوك وتراكيبينيس كيرفيروسترس ستمبسون يمثلان 2.7% فقط من المصيد .
وتكون النسبة المئوية من الأنواع الكبيرة 47% من بينيس جابونيكس ، 30% ب . لاتيسلكاتس ، 23% ب . سيمسكاتس وتحدث فترة الصيد المكثف من أكتوبر إلى مايو وتقع في نفس الوقت الذي يضع فيه بينيس سميلكاتس بيض ( أكتوبر - مارس ) . يمثل منتصف النصف الشمالي من الخليج أغنى مناطقه بالنسبة للأنواع الرئيسية الثلاثة ، ومن ناحية الوزن حدث هبوط عام في معدل الانتاج لكل وحدة جهد من بداية موسم الصيد وحتى يناير - فبراير ثم زاد قليلاً بعد ذلك وربما كان ذلك لقدوم أفراد جديدة من ب . لاتسلكاتس إلى منطقة الصيد .
ولقد أعطى موسم 1983 - 1984 إنتاجاً عالياً من الجمبري الكبير ( 749 طناً ) وذلك بجهد وصل الى 13690 يوم صيد
The Association of Intraoperative driving pressure with postoperative pulmonary complications in open versus closed abdominal surgery patients - a posthoc propensity score-weighted cohort analysis of the LAS VEGAS study
BackgroundIt is uncertain whether the association of the intraoperative driving pressure (Delta P) with postoperative pulmonary complications (PPCs) depends on the surgical approach during abdominal surgery. Our primary objective was to determine and compare the association of time-weighted average Delta P (Delta P-TW) with PPCs. We also tested the association of Delta P-TW with intraoperative adverse events.MethodsPosthoc retrospective propensity score-weighted cohort analysis of patients undergoing open or closed abdominal surgery in the 'Local ASsessment of Ventilatory management during General Anaesthesia for Surgery' (LAS VEGAS) study, that included patients in 146 hospitals across 29 countries. The primary endpoint was a composite of PPCs. The secondary endpoint was a composite of intraoperative adverse events.ResultsThe analysis included 1128 and 906 patients undergoing open or closed abdominal surgery, respectively. The PPC rate was 5%. Delta P was lower in open abdominal surgery patients, but Delta P-TW was not different between groups. The association of Delta P-TW with PPCs was significant in both groups and had a higher risk ratio in closed compared to open abdominal surgery patients (1.11 [95%CI 1.10 to 1.20], P < 0.001 versus 1.05 [95%CI 1.05 to 1.05], P < 0.001; risk difference 0.05 [95%CI 0.04 to 0.06], P < 0.001). The association of <Delta>P-TW with intraoperative adverse events was also significant in both groups but had higher odds ratio in closed compared to open abdominal surgery patients (1.13 [95%CI 1.12- to 1.14], P < 0.001 versus 1.07 [95%CI 1.05 to 1.10], P < 0.001; risk difference 0.05 [95%CI 0.030.07], P < 0.001).Conclusions<Delta>P is associated with PPC and intraoperative adverse events in abdominal surgery, both in open and closed abdominal surgery.Trial registrationLAS VEGAS was registered at clinicaltrials.gov (trial identifier NCT01601223)
Intraoperative ventilator settings and their association with postoperative pulmonary complications in neurosurgical patients: Post-hoc analysis of LAS VEGAS study
Background: Limited information is available regarding intraoperative ventilator settings and the incidence of postoperative pulmonary complications (PPCs) in patients undergoing neurosurgical procedures. The aim of this post-hoc analysis of the 'Multicentre Local ASsessment of VEntilatory management during General Anaesthesia for Surgery' (LAS VEGAS) study was to examine the ventilator settings of patients undergoing neurosurgical procedures, and to explore the association between perioperative variables and the development of PPCs in neurosurgical patients. Methods: Post-hoc analysis of LAS VEGAS study, restricted to patients undergoing neurosurgery. Patients were stratified into groups based on the type of surgery (brain and spine), the occurrence of PPCs and the assess respiratory risk in surgical patients in Catalonia (ARISCAT) score risk for PPCs. Results: Seven hundred eighty-four patients were included in the analysis; 408 patients (52%) underwent spine surgery and 376 patients (48%) brain surgery. Median tidal volume (VT) was 8 ml [Interquartile Range, IQR = 7.3-9] per predicted body weight; median positive end-expiratory pressure (PEEP) was 5 [3 to 5] cmH20. Planned recruitment manoeuvres were used in the 6.9% of patients. No differences in ventilator settings were found among the sub-groups. PPCs occurred in 81 patients (10.3%). Duration of anaesthesia (odds ratio, 1.295 [95% confidence interval 1.067 to 1.572]; p = 0.009) and higher age for the brain group (odds ratio, 0.000 [0.000 to 0.189]; p = 0.031), but not intraoperative ventilator settings were independently associated with development of PPCs. Conclusions: Neurosurgical patients are ventilated with low VT and low PEEP, while recruitment manoeuvres are seldom applied. Intraoperative ventilator settings are not associated with PPCs
Association between night-time surgery and occurrence of intraoperative adverse events and postoperative pulmonary complications
Background: The aim of this post hoc analysis of a large cohort study was to evaluate the association between night-time surgery and the occurrence of intraoperative adverse events (AEs) and postoperative pulmonary complications (PPCs). Methods: LAS VEGAS (Local Assessment of Ventilatory Management During General Anesthesia for Surgery) was a prospective international 1-week study that enrolled adult patients undergoing surgical procedures with general anaesthesia and mechanical ventilation in 146 hospitals across 29 countries. Surgeries were defined as occurring during \u2018daytime\u2019 when induction of anaesthesia was between 8:00 AM and 7:59 PM, and as \u2018night-time\u2019 when induction was between 8:00 PM and 7:59 AM. Results: Of 9861 included patients, 555 (5.6%) underwent surgery during night-time. The proportion of patients who developed intraoperative AEs was higher during night-time surgery in unmatched (43.6% vs 34.1%; P<0.001) and propensity-matched analyses (43.7% vs 36.8%; P=0.029). PPCs also occurred more often in patients who underwent night-time surgery (14% vs 10%; P=0.004) in an unmatched cohort analysis, although not in a propensity-matched analysis (13.8% vs 11.8%; P=0.39). In a multivariable regression model, including patient characteristics and types of surgery and anaesthesia, night-time surgery was independently associated with a higher incidence of intraoperative AEs (odds ratio: 1.44; 95% confidence interval: 1.09\u20131.90; P=0.01), but not with a higher incidence of PPCs (odds ratio: 1.32; 95% confidence interval: 0.89\u20131.90; P=0.15). Conclusions: Intraoperative adverse events and postoperative pulmonary complications occurred more often in patients undergoing night-time surgery. Imbalances in patients\u2019 clinical characteristics, types of surgery, and intraoperative management at night-time partially explained the higher incidence of postoperative pulmonary complications, but not the higher incidence of adverse events. Clinical trial registration: NCT01601223
Association between night-time surgery and occurrence of intraoperative adverse events and postoperative pulmonary complications
Background: The aim of this post hoc analysis of a large cohort study was to evaluate the association between night-time surgery and the occurrence of intraoperative adverse events (AEs) and postoperative pulmonary complications (PPCs)
Intraoperative ventilator settings and their association with postoperative pulmonary complications in neurosurgical patients: post-hoc analysis of LAS VEGAS study
Background: Limited information is available regarding intraoperative ventilator settings and the incidence of postoperative pulmonary complications (PPCs) in patients undergoing neurosurgical procedures. The aim of this post-hoc analysis of the 'Multicentre Local ASsessment of VEntilatory management during General Anaesthesia for Surgery' (LAS VEGAS) study was to examine the ventilator settings of patients undergoing neurosurgical procedures, and to explore the association between perioperative variables and the development of PPCs in neurosurgical patients.
Methods: Post-hoc analysis of LAS VEGAS study, restricted to patients undergoing neurosurgery. Patients were stratified into groups based on the type of surgery (brain and spine), the occurrence of PPCs and the assess respiratory risk in surgical patients in Catalonia (ARISCAT) score risk for PPCs.
Results: Seven hundred eighty-four patients were included in the analysis; 408 patients (52%) underwent spine surgery and 376 patients (48%) brain surgery. Median tidal volume (VT) was 8 ml [Interquartile Range, IQR = 7.3-9] per predicted body weight; median positive end-expiratory pressure (PEEP) was 5 [3 to 5] cmH20. Planned recruitment manoeuvres were used in the 6.9% of patients. No differences in ventilator settings were found among the sub-groups. PPCs occurred in 81 patients (10.3%). Duration of anaesthesia (odds ratio, 1.295 [95% confidence interval 1.067 to 1.572]; p = 0.009) and higher age for the brain group (odds ratio, 0.000 [0.000 to 0.189]; p = 0.031), but not intraoperative ventilator settings were independently associated with development of PPCs.
Conclusions: Neurosurgical patients are ventilated with low VT and low PEEP, while recruitment manoeuvres are seldom applied. Intraoperative ventilator settings are not associated with PPCs