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The industrial use of cryogenic air separation units started more than 130 years ago. Cryogenic air separation units produce oxygen, pure nitrogen and argon in liquid and/or gaseous state. Different configurations of these cryogenic plants lead to different quantities of gas and liquid products. In addition, product purity is also affected by the proposed scheme. As a result, the paper analyzes different variants of installations for the separation of binary gas mixtures based on the Linde process. By comparing energy indices and constructive considerations, the separation plant with external air pre-cooling and the use of a single-stage separation column is chosen. Finally, a study is carried out on the processes in the separation column and a calculation of the minimum mechanical work of separation. The real air consumption curve will also be built, with the help of which we shall determine what quantities of O2 and N2 are obtained by air separation at a specific consumption. [ABSTRACT FROM AUTHOR]

To investigate the correlation between lower urinary tract symptoms (LUTS), erectile dysfunction (ED), and testosterone deficiency (TD) with depressive, stress, and anxiety symptoms. From October 2019 to March 2020, 113 males were included. Inclusion criteria: age 40–75, no clinical suspicion of prostate cancer, no serious cardiovascular comorbidities. All patients completed a set of questionnaires: International Prostate Symptom Score (IPSS), International Index of Erectile Function (IIEF-5), and Depression Anxiety Stress Scales (DASS-21). Median age was 62 years (range 40–74), mean IPSS score was 10.94 (SD 7.75), mean IIEF-5 score 13.12 (SD 7.08), and mean DASS-21 score 11.35 (SD 8.24). According to DASS-21 subscales, 28 (24.8%) patients had depressive symptoms, 25 (22.1%) anxiety symptoms, and 25 (22.1%) stress symptoms. Depression was associated with LUTS (14.5 vs. 8 score, p =.002). Similarly, stress symptoms were associated with LUTS (IPSS 15 vs. 7 score, p =.0001) and with ED (IIEF-5 5 vs. 15 score, p =.01). Positive Spearman's rho correlations between LUTS and all three, depression, anxiety, and stress symptoms were found (p values <.001). LUTS is associated with depression, anxiety, and stress symptoms. Screening for these symptoms could help with individual counseling and management. [ABSTRACT FROM AUTHOR]

Background: Quality of life (QoL) and psychological distress represent an important aspect of the daily life of cancer patients. The aim of this systematic review was to critically analyze available literature regarding QoL and psychological distress in patients with small renal masses (SRMs). (2) Methods: A systematic search of EMBASE, PUBMED and American Psychological Association (APA-net) was performed on 30 April 2022. Studies were considered eligible if they included patients with SRMs, had a prospective or retrospective design, included at least 10 patients, were published in the last 20 years, and assessed the QoL or psychological distress in patients that underwent active surveillance (AS) in comparison to those that underwent ablation/surgery treatments. (3) Results: The patients that underwent AS were statistically significantly older, with smaller renal masses than those that underwent surgery/ablation. A study showed a significant reduction in total scores of Short Form-12 (SF-12) among AS patients when compared to partial nephrectomy (PN) patients at enrollment (95.0 ± 15.8 vs. 99.1 ± 13.9), 2 years (91.0 ± 16.4 vs. 100.3 ± 14.3), and at 3 years (92.9 ± 15.9 vs. 100.3 ± 14.3), p < 0.05, respectively. That was mainly due to lower physical health scores. On the other hand, another study showed that AS patients with a biopsy-proven malignant tumor had a worse psychological distress sub-score (PDSS) compared to patients treated with surgery/ablation after biopsy. (4) Conclusions: It seems that there is an influence on QoL and psychological distress while on AS of SMRs. However, due to the low amount of available data, the impact of AS or active treatment on QoL or psychological distress of patients with small renal masses warrants further investigation. [ABSTRACT FROM AUTHOR]

A solar driven cooling system consisting of a single effect H2O-LiBr absorbtion cooling module (ACS), a parabolic trough collector (PTC), and a storage tank (ST) module is analyzed during one full day operation. The pressurized water is used to transfer heat from PTC to ST and to feed the ACS desorber. The system is constrained to operate at the maximum ACS exergetic efficiency, under a time dependent cooling load computed on 15 July for a one storey house located near Bucharest, Romania. To set up the solar assembly, two commercial PTCs were selected, namely PT1-IST and PTC 1800 Solitem, and a single unit ST was initially considered. The mathematical model, relying on the energy balance equations, was coded under Engineering Equation Solver (EES) environment. The solar data were obtained from the Meteonorm database. The numerical simulations proved that the system cannot cover the imposed cooling load all day long, due to the large variation of water temperature inside the ST. By splitting the ST into two units, the results revealed that the PT1-IST collector only drives the ACS between 9 am and 4:30 pm, while the PTC 1800 one covers the entire cooling period (9 am-6 pm) for optimum ST capacities of 90 kg/90 kg and 90 kg/140 kg, respectively. [ABSTRACT FROM AUTHOR]

A simple effect one stage ammonia-water absorption cooling system fueled by solar energy is analyzed. The considered system is composed by a parabolic trough collector concentrating solar energy into a tubular receiver for heating water. This is stored in a fully mixed thermal storage tank and used in the vapor generator of the absorption cooling system. Time dependent cooling load is considered for the air conditioning of a residential two-storey house. A parametric study is performed to analyze the operation stability of the cooling system with respect to solar collector and storage tank dimensions. The results emphasized that there is a specific storage tank dimension associated to a specific solar collector dimension that could ensure the longest continuous startup operation of the cooling system when constant mass flow rates inside the system are assumed. [ABSTRACT FROM AUTHOR]

As part of the efforts to unify the various branches of Irreversible Thermodynamics, the proposed work reconsiders the approach of the Carnot engine taking into account the finite physical dimensions (heat transfer conductances) and the finite speed of the piston. The models introduce the irreversibility of the engine by two methods involving different constraints. The first method introduces the irreversibility by a so-called irreversibility ratio in the entropy balance applied to the cycle, while in the second method it is emphasized by the entropy generation rate. Various forms of heat transfer laws are analyzed, but most of the results are given for the case of the linear law. Also, individual cases are studied and reported in order to provide a simple analytical form of the results. The engine model developed allowed a formal optimization using the calculus of variations. [ABSTRACT FROM AUTHOR]

Copyright of Journal for Neurology & Psychiatry of Child & Adolescent in Romania is the property of Romanian Society of Child & Adolescent Neurology & Psychiatry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Along with the passage of time, parents have manifested a different attitude towards their children, trying to offer them everything they wanted in what concerns the toys. Therefore, the toy market is constantly expending, and the tough competition leads to the quality improvement of the toys and enforces certain standards on the market. The originality and topicality of the theme consist in the change in the toy consumers' and users' preferences which required greater attention to be paid to the influence manifested by the marketing environment on this market. The case study identifies the occurred problems and the toy influence factors by an analysis over the marketing environment components, i.e.: marketing internal environment, micro-environment and macro-environment. The study ends with the recommendation of several solutions for the improvement of the current situation. [ABSTRACT FROM AUTHOR]

Copyright of Journal for Neurology & Psychiatry of Child & Adolescent in Romania is the property of Romanian Society of Child & Adolescent Neurology & Psychiatry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Several optimization models of irreversible reverse cycle machines have been developed based on different optimization criteria in the literature, most of them using linear heat transfer laws at the source and sink. This raises the issue how close to actual operation conditions they are, since the heat transfer law on the phase-change processes is dependent on ΔT3. This paper addresses this issue by proposing a general model for study and optimization of thermal machines with two heat reservoirs applied to a Carnot-like refrigerator, with non-linear heat transfer laws and internal and external irreversibility. The optimization was performed using First and Second Law of Thermodynamics and the Lagrange multipliers method. Thus, several constraints were imposed to the system, also different objective functions were considered, allowing finding the optimum operating conditions, as well as the limited variation ranges of the system parameters. Results show that the nature of the heat transfer laws affects the optimum values of system parameters for obtaining maximum performances and also their magnitude. Sensitivity studies with respect to system several parameters are presented. The results contribute to the understanding of the system limits in operation under different constraints and allow choosing the most convenient variables in given circumstances. [ABSTRACT FROM AUTHOR]