Effect of screening of the electron-phonon interaction on the temperature of Bose-Einstein condensation of intersite bipolarons

Here we consider an interacting electron-phonon system within the framework of extended Holstein-Hubbard model at strong enough electron-phonon interaction limit in which (bi)polarons are the essential quasiparticles of the system. It is assumed that the electron-phonon interaction is screened and its potential has Yukawa-type analytical form. An effect of screening of the electron-phonon interaction on the temperature of Bose-Einstein condensation of the intersite bipolarons is studied for the first time. It is revealed that the temperature of Bose-Einstein condensation of intersite bipolarons is higher in the system with the more screened electron-phonon interaction.Comment: 6 pages, 4 figure

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

Phonon distributions of a single bath mode coupled to a quantum dot

The properties of an unconventional, single mode phonon bath coupled to a quantum dot, are investigated within the rotating wave approximation. The electron current through the dot induces an out of equilibrium bath, with a phonon distribution qualitatively different from the thermal one. In selected transport regimes, such a distribution is characterized by a peculiar selective population of few phonon modes and can exhibit a sub-Poissonian behavior. It is shown that such a sub-Poissonian behavior is favored by a double occupancy of the dot. The crossover from a unequilibrated to a conventional thermal bath is explored, and the limitations of the rotating wave approximation are discussed.Comment: 21 Pages, 7 figures, to appear in New Journal of Physics - Focus on Quantum Dissipation in Unconventional Environment

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

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

Central Processing Unit Binary Cooling System using Tetrafluoroethane as Refrigerant

Electronic devices and instruments generate heat that can cause serious damage and low efficiency towards its components. The heat that the different electronic elements and components emit can decrease both efficiency and life capacity of the device. And with the increase of use of electronic devices in industries and processes, heat dissipation in electronic devices should be taken into strict consideration. This study aims to develop a cooling system under vapor compression refrigeration system. The prototype fabricated was designed for the cooling system of two Central Processing Units of desktop computer which can be as good equivalent for the electronic devices in industries. Though ventilation was present in the processing units, certain condition such as condition in surroundings can be of great help to improve the device efficiency. This study also aims to analyze the CPU’s efficiency in relation to lowering ventilation temperatures. The vapor compression refrigeration system will be the main device used for lowering and maintaining a suitable temperature inside the CPU casing. The system works like a centralized air-conditioning system wherein the air from the surroundings will be cooled down by the evaporator in the vapor compression refrigeration system. The cooled air will then be delivered to the CPU through the installed air ducting connections. The recording of CPU’s efficiency is provided by the installed software. It also measures the air conditioned parameters and computation of the CPU power consumption. The results from the test and the analysis of the gathered data showed that 165 watts of heat dissipated was removed by the cooling system and the CPU performance index rose up from 424 to 446 with a discharge air temperature of 29.67 oC. Based from the result, the fabricated binary cooling system is efficient enough to increase the performance index of the CPU and absorbing heat dissipated by the device.</jats:p

Utilization of mung bean, Vigna radiata (Linnaeus) as a novel protein source in practical-type diets for juvenile milkfish, Chanos chanos (Forsskal): Effects on growth, feed efficiency, body composition, and histology of gut and liver

A 15-week feeding trial was conducted to determine the optimum partial inclusion of mung bean protein in milkfish diet. Six isonitrogenous practical-type diets with mung bean included at 0%, 4%, 8%, 12%, 16%, and 20% of the diet equivalent to 0%, 3%, 7%, 10%, 13%, and 17% of the total dietary protein, respectively, were formulated. Milkfish with average body weight (ABW) of 8.5 ± 0.23g were distributed in eighteen tanks (6 treatments X 3 replications) with 10 fish each. The fish were fed the diets three times daily. Results showed that growth of milkfish was not adversely affected by the inclusion of mung bean protein at any dietary level. Feed conversion ratio (FCR) and protein efficiency ratio (PER) were significantly improved by the inclusion of mung bean at 20% of the diet. Nutrient compositions of the fish carcass were similar in all diets. Furthermore, no detrimental effects attributable to mung bean inclusion were seen in terms of protein retention, hepatosomatic index (HSI), and liver and midgut histology of the fish. Overall, mung bean is a promising protein source for milkfish and can be included up to 20% of the diet contributing as much as 17% of the total dietary protein without detrimental effects on growth, feed performance, PER, protein retention, HSI, and liver and intestinal histology.This study was funded by the Department of Science and Technology (DOST) through the Philippine Council for Agriculture, Aquatic, and Natural Resources Research and Development (PCAARRD)

Digital Technology Experiences of BSED-Science Students in A State University

In response to transformation of educational landscape, schools all over the world have begun using digital technology to boost students’ interest and academic performance. Students have been exposed to new learning methods that involve technology. However, excessive and irresponsible use of digital technology may lead to more dangers than benefits. Some of these disadvantages such as poor academic performance, academic failure, or unsatisfactory grades (Flanagan, 2008) prove that an increased amount of time that the youth spend on these activities poses negative effects to their online learning. This prompted the researchers to conduct a study on the advantages and drawbacks of digital technology. It used an explanatory-sequential research design and utilized convenience sampling for the quantitative phase using questionnaire. There were 15 participants randomly selected from 100 BSED students Major in Science for the qualitative phase and were also interviewed using Guide Questions. The qualitative data was evaluated using thematic analysis, while the quantitative data was analyzed through descriptive statistical analysis and exploratory factor analysis using Jeffrey's Amazing Statistics Application (JASP). Findings revealed that students use various digital technologies for both educational and non-educational purposes, such as smartphones and Google Classroom, and Facebook and Mobile Legends, respectively. The impact of digital technology on students' online learning can be either favorable or detrimental, depending on the students' experiences, perspective or attitude, and utilization.</jats:p