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Author(s):  
Dilmukhammad D. Atambaev ◽  

This paper examines the differences between the main purpose of the process of falling from individual fibers in a given linear density, density and elasticity and the methods of determining the hairiness of the yarn, the hairiness of the yarn is determined by the number of knots per unit length.


BMC Surgery ◽  
2022 ◽  
Vol 22 (1) ◽  
Author(s):  
Woubet Tefera Kassahun ◽  
Matthias Mehdorn ◽  
Jonas Babel

Abstract Background Obesity has been shown to increase the rates of morbidity and occasionally mortality in patients undergoing nonbariatric elective surgery. However, little is known about the impact of obesity on outcomes after surgery for high-risk abdominal emergencies. Methods A single-center retrospective evaluation of outcomes in high-risk abdominal emergency patients categorized by body mass index (BMI) was conducted. Patient demographics, comorbidities, and operative details were analyzed. Patients with normal weight (BMI 18.5–24.9) served as comparators. Multivariable linear and logistic regression analyses were performed to assess the impact of obesity on surgical outcomes. Results In total, 886 patients with BMI < 18.5 (underweight; n = 50), 18.5–24.9 (normal weight; n = 306), 25–29.9 (overweight; n = 336) and ≥ 30 (obese; n = 194) based on the World Health Organization (WHO) weight classification criteria met the inclusion criteria. Compared to normal-weight patients, patients with overweight and obesity were older and more likely to be male. The rates of comorbidity (100% vs 91.2%, p =  < 0.0001), morbidity (77.8% vs 65.6%, p = 0.003), and in-hospital mortality (44.8% vs 30.4%, p = 0.001) were all higher in patients with obesity than in normal-weight patients. Patients with obesity had an increased intensive care unit length of stay (ICU LOS) (13 days vs 9 days, p = 0.019) and hospital LOS (21.4 days vs 18.1 days, p = 0.081) and prolonged ventilation (39.1% vs 19.6%, p = 0.003). As BMI deviated from the normal range, the morbidity and mortality rates increased incrementally, with the highest morbidity (87.9%) and mortality (54.5%) rates observed in morbidly obese patients (BMI ≥ 40). Conclusions Patients with obesity were the most likely to have coexisting conditions, experience postoperative complications, and die during the first admission following EL for high-risk abdominal emergencies.


Life ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 103
Author(s):  
Benjamin D. Lee ◽  
Eugene V. Koonin

Viroids are a unique class of plant pathogens that consist of small circular RNA molecules, between 220 and 450 nucleotides in size. Viroids encode no proteins and are the smallest known infectious agents. Viroids replicate via the rolling circle mechanism, producing multimeric intermediates which are cleaved to unit length either by ribozymes formed from both polarities of the viroid genomic RNA or by coopted host RNAses. Many viroid-like small circular RNAs are satellites of plant RNA viruses. Ribozyviruses, represented by human hepatitis delta virus, are larger viroid-like circular RNAs that additionally encode the viral nucleocapsid protein. It has been proposed that viroids are direct descendants of primordial RNA replicons that were present in the hypothetical RNA world. We argue, however, that much later origin of viroids, possibly, from recently discovered mobile genetic elements known as retrozymes, is a far more parsimonious evolutionary scenario. Nevertheless, viroids and viroid-like circular RNAs are minimal replicators that are likely to be close to the theoretical lower limit of replicator size and arguably comprise the paradigm for replicator emergence. Thus, although viroid-like replicators are unlikely to be direct descendants of primordial RNA replicators, the study of the diversity and evolution of these ultimate genetic parasites can yield insights into the earliest stages of the evolution of life.


2022 ◽  
Vol 0 (0) ◽  
Author(s):  
Ghulam Abbas Khushik ◽  
Ari Huhta

Abstract The increasing importance of the Common European Framework of Reference (CEFR) has led to research on the linguistic characteristics of its levels, as this would help the application of the CEFR in the design of teaching materials, courses, and assessments. This study investigated whether CEFR levels can be distinguished with reference to syntactic complexity (SC). 14- and 17-year-old Finnish learners of English (N=397) wrote three writing tasks which were rated against the CEFR levels. The ratings were analysed with multi-facet Rasch analysis and the texts were analysed with automated tools. Findings suggest that the clearest separators at lower CEFR levels (A1–A2) were the mean sentence and T-unit length, variation in sentence length, infinitive density, clauses per sentence or T-unit, and verb phrases per T-unit. For higher levels (B1–B2) they were modifiers per noun phrase, mean clause length, complex nominals per clause, and left embeddedness. The results support previous findings that the length of and variation in the longer production units (sentences, T-units) are the SC indices that most clearly separate the lower CEFR levels, whereas the higher levels are best distinguished in terms of complexity at the clausal and phrasal levels.


Energies ◽  
2022 ◽  
Vol 15 (1) ◽  
pp. 280
Author(s):  
Filip Lisowski ◽  
Edward Lisowski

The use of cryogenic liquefied gasses in industry is constantly increasing both for process purposes and for power supply needs. The liquefied natural gas (LNG) is stored at cryogenic temperature and its immediate use in gaseous form requires its evaporation. The heat needed to cause a phase change is usually delivered by means of vaporizers. This paper presents a numerical analysis of the influence of the fins number and frost accumulated within the fins surface on the heat transferred through the aluminum finned tubes of LNG ambient air vaporizers. The calculations were carried out applying finite element thermal analysis within Ansys software as well as using an analytical approach. As a result, the heat rate per unit length of the finned tube was obtained. The results were compared for different numbers of longitudinal fins both without frost and for total frosting of the tubes.


2021 ◽  
Vol 27 (1) ◽  
pp. 45-50
Author(s):  
Mallory C. Cowart ◽  
Travis S. Heath ◽  
Andrakeia Shipman

OBJECTIVE The purpose of this study was to determine if administration of antibiotics within 1 hour of meeting sepsis criteria improved patient outcomes versus antibiotics administered greater than 1 hour after meeting sepsis criteria in pediatric patients. The Surviving Sepsis Campaign's international guidelines recommend appropriate antimicrobial therapy be administered within 1 hour of recognition of severe sepsis or septic shock. Data regarding outcomes in pediatric patients with sepsis regarding antibiotic timing are currently limited. METHODS This was a retrospective chart review of 69 pediatric patients admitted between July 1, 2013, and June 30, 2016, with a diagnosis of sepsis. RESULTS The primary outcome of in-hospital mortality was 7.1% in the within 1 hour group versus 14.6% in the greater than 1 hour group (p = 0.3399). Median hospital length of stay was significantly shorter in the within 1 hour group (15.4 versus 39.2 days, p = 0.0022). Median intensive care unit length of stay was also significantly shorter in the within 1 hour group (3.1 versus 33.6 days, p = 0.0191). There were no differences between groups for pediatric intensive care unit admission, end organ dysfunction, time to intubation, or time on the ventilator. CONCLUSIONS Pediatric patients who receive antimicrobial therapy within 1 hour of meeting sepsis criteria had improved hospital and intensive care unit length of stay. This study supports the Surviving Sepsis Guidelines recommendation to administer antibiotics within 1 hour in pediatric patients with sepsis or septic shock.


2021 ◽  
Author(s):  
Eric Wasilewski ◽  
Nikolay Doynov ◽  
Ralf Ossenbrink ◽  
Vesselin Michailov

Abstract This work presents a comparative study of thermal conditions that occur during laser beam welding of high strength steel 100Cr6 that often leads to a loss of technological strength and may conditionally produce cold cracks. The results from both experiments and thermal-metallurgical FE-simulations indicate that the type of heat coupling changes significantly when welding with different process parameters, e.g., in the transition between conduction and deep penetration welding. Further, the simulations show that as a result of the high welding speeds and reduced energy per unit length, extremely high heating rates of up to 2x104 K s-1 (set A) resp. 4x105 K s-1 (set B) occur in the material. Both welds thus concern a range of values for which conventional Time-Temperature-Austenitization (TTA) diagrams are not currently defined, so that the material models can only be calibrated using general assumptions. This noted change in energy per unit length and welding speeds causes significantly steep temperature gradients with a slope of approximately 5x103 K mm-1 and strong drops in the heating and cooling rates, particularly in the heat affected zone near the weld metal. This means that even short distances along the length present a staggering difference in relation to the temperature peaks. The temperature cycles also show very different cooling rates for the respective parameter sets, although in both cases they are well below a cooling time t8/5 of one second, so that the phase transformation always leads to the formation of martensite. The results from this study are intended to be used for further detailed experimental and numerical investigation of microstructure, hydrogen distribution, and stress-strain development at different restrain conditions.


Author(s):  
Shuai Ma ◽  
Qian Tang ◽  
Ying Liu ◽  
Qixiang Feng

Abstract Lattice structures (LS) manufactured by 3D printing are widely applied in many areas, such as aerospace and tissue engineering, due to their lightweight and adjustable mechanical properties. It is necessary to reduce costs by predicting the mechanical properties of LS at the design stage since 3D printing is exorbitant at present. However, predicting mechanical properties quickly and accurately poses a challenge. To address this problem, this study proposes a novel method that is applied to different LS and materials to predict their mechanical properties through machine learning. First, this study voxelized 3D models of the LS units and then calculated the entropy vector of each model as the geometric feature of the LS units. Next, the porosity, material density, elastic modulus, and unit length of the lattice unit are combined with entropy as the inputs of the machine learning model. The sample set includes 57 samples collected from previous studies. Support vector regression (SVR) was used in this study to predict the mechanical properties. The results indicate that the proposed method can predict the mechanical properties of LS effectively and is suitable for different LS and materials. The significance of this work is that it provides a method with great potential to promote the design process of lattice structures by predicting their mechanical properties quickly and effectively.


2021 ◽  
Vol 9 (12) ◽  
pp. 1431
Author(s):  
Aleksandr Zolotnitsky ◽  
Nataliy Sytnik ◽  
Sergei Chernyi ◽  
Natalya Logunova

The influence of the area of artificial substrates (collectors) on the biological parameters of populations of mussels (Mytilus galloprovincialis Lamarck) during their cultivation in the Black Sea has been investigated. For growing mollusks, four types of collectors were used, with different relative areas (ω), i.e., with different ratios of the substrate area (S) per unit length of the collector (L), which were 0.09, 0.21, 0.34, and 0.55. It was found that, during a 1.5-year cultivation, the density (N, ind./m) and biomass (B, kg/m) change and reach a certain stationary state, determined by the relative area of the substrate. It was shown that, on collectors with a higher value of ω, there was a decrease in the average length (L, mm) and weight (W, g) of the mollusk yield. The Boysen–Jensen method was used to calculate the total production of mollusks (P), elimination (E), and specific production (P/B coefficient) for each type of reservoir, and it was shown that P increased with an increase in the substrate area, while E and P/B coefficients decreased. Based on the analysis of the obtained results, it was concluded that during the cultivation of mussels these parameters are regulated by density-dependent population factors (intraspecific competition) for space (substrate) and food.


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