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The present paper approaches of plates subjected to transverse loads, when the shear force and the actual boundary conditions are considered, by using the Finite Element Method. The isoparametric finite elements create real facilities in formulating the problems and great possibilities in creating adequate computer programs.

Some considerations concerning the design of the paraboloidal suspended roofs are made. The main geometric aspects are first time presented. For the roofs we propose, as pattern, the equivalent continuum membranes, and the efforts in the cable are determined by using the membrane efforts and their equations. Two examples are analyzed: elliptic paraboloide and hyperbolic paraboloide, with horizontal projection under the form of an ellipse.

Retaining walls are large category of engineering structures of multiple uses, having an essential safety ensuring role. The structural systems are varied because the situations and requirements derived from both site conditions and other criteria are varied. The paper enlarges upon retaining walls systems that use an outstanding amount of precast units and multiple cylindrical vault type structural systems supported by abutments [1], [2]. The paper proposes extending the structural system to retaining walls and develops certain specific issues. Some considerations regarding structural design are made.

Mohr’s theory concerning the stress limit state and its use in determining the active and passive soil pressures on retaining walls is being developed. Rankine’s hypothesis, according to which the pressures on surface elements that are parallel to the free surface of ground have a vertical direction; the horizontal acceleration effect which generates inertia forces in the soil are accounted for. On these grounds the normal and tangential stresses on planes parallel to the back – of – wall ground surface are being expressed. By using the intrinsic curve corresponding to the sliding and the stresses expressed on these planes, Mohr’s limit circles, as well as the active and the passive pressures generated by the seismic event on the retaining wall are determined. The solving process is an essentially graphic one and allows for the finding of the sliding plane and the main normal stresses as well as the extreme tangential ones in the points of this plane in which the tension state has reached the limit.

General numerical methods based on the discretization of the surface between structure and soil in finite elements are developed and, by their help, the stiffness matrix is determined. There are considered the medium model of linear elastic, homogeneous and isotropic half-space and anisotropic half-space, respectively. In case of rigid structures or with rigid base, it is essentially for their response evaluation to know the stiffness coefficients.

This paper presents the results obtained regarding the realization of a functional model of equipment for managing in-depth amendments on salted lands and the results regarding the effect of the work performed in three soil conditions. At the same time, the physical properties of the amendment used (phosphogypsum), determined in laboratory conditions, in order to know the problems that may occur during the application work, are presented. [ABSTRACT FROM AUTHOR]

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering 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.)

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering 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.)

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering 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.)

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering 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.)

The article describes the results of long-term research on the dynamics of vanadium migration in water, bottom sediments, higher aquatic plants, bottom invertebrates, and fishes in the cooling reservoir of the Moldovan Thermal Power Plant. An obvious dependence of the level of vanadium in aquatic ecosystem on the quantity and composition of burnt fuel at the plant was established. In most of cases the migration of vanadium in the system “water – silts” occured from water layers to bottom sediments. But if the intensity of sulphate reduction and putrefaction processes increases and the concentration of dissolved oxygen decreases the reverse diffusion from silts to water will become possible. The level of accumulation of metals in hydrobionts is one of the most important parameters in the biomonitoring of metals in aquatic ecosystems. The concentration of vanadium in aquatic plants and animals depended on the intensity of metabolism and interspecific features, plastic and generative metabolism (at fish), but in the same time reflected the dynamics of vanadium in the environment. The values of the coefficient of vanadium biological accumulation in aquatic organisms reached up to n×107

Supraglottic airway devices are commonly used to manage the airway during general anaesthesia. There are sporadic case reports of temporomandibular joint dysfunction and dislocation following supraglottic airway device use. We conducted a prospective observational study of adult patients undergoing elective surgery where a supraglottic airway device was used as the primary airway device. Pre-operatively, all participants were asked to complete a questionnaire involving 12 points adapted from the Temporomandibular Joint Scale and the Liverpool Oral Rehabilitation Questionnaire. Objective measurements included inter-incisor distance as well as forward and lateral jaw movements. The primary outcome was the inter-incisor distance, an accepted measure of temporomandibular joint mobility. Both the questionnaire and measurements were repeated in the postoperative period and we analysed data from 130 participants. Mean (SD) inter-incisor distance in the pre- and postoperative period was 46.5 (7.2) mm and 46.3 (7.5) mm, respectively (p = 0.521) with a difference (95%CI) of 0.2 (-0.5 to 0.9) mm. Mean (SD) forward jaw movement in the pre- and postoperative period was 3.6 (2.4) mm and 3.9 (2.4) mm, respectively (p = 0.018). Mean (SD) lateral jaw movement to the right in the pre- and postoperative period was 8.9 (4.1) mm and 9.1 (4.0) mm, respectively (p = 0.314). Mean (SD) lateral jaw movement to the left in the pre- and postoperative period was 8.8 (4.0) mm and 9.3 (3.6) mm, respectively (p = 0.008). The number of patients who reported jaw clicks or pops before opening their mouth as wide as possible was 28 (21.5%) vs. 12 (9.2%) in the pre- and postoperative period, respectively (p < 0.001) with a difference (95%CI) of 12.3% (6.7-17.9%). There was no significant difference in the responses to the other 11 questions or in the number of patients who reported pain in the temporomandibular joint area postoperatively. No clinically significant dysfunction of the temporomandibular joint following the use of supraglottic airway devices in the postoperative period was identified by either patient questionnaires or objective measurements., (© 2021 Association of Anaesthetists.)

Head and neck position is one of the factors which can be associated with difficult videolaryngoscopy and tracheal intubation. This prospective randomised clinical trial compared 'sniffing' and neutral positions using a channelled (KingVision ® ) and a non-channelled (C-MAC ® D-blade) videolaryngoscope in 200 adult patients randomly allocated into four groups (KingVision 'sniffing', KingVision neutral, C-MAC 'sniffing' and C-MAC neutral). The primary outcome was the ease of tracheal intubation using the modified intubation difficulty scale (mIDS) score. Laryngoscopy time, intubation time, laryngoscopic view using the percentage of glottic opening (POGO) score and success rate of tracheal intubation were secondary outcomes. The median (IQR [range]) modified difficulty scale scores for the four groups, respectively, were 0 (0-1 [0-3]), 0 (0-1 [0-4]), 1 (0-1 [0-5]) and 0 (0-1 [0-3]; p = 0.384). There was no significant difference in laryngoscopy time (p = 0.020), intubation time (p = 0.272) and success rate (p = 0.968) between the groups. The percentage of glottic opening score was lower for C-MAC neutral group as compared with other three groups (p = 0.01). There was no significant difference in the ease of intubation between the 'sniffing' and the neutral position when using the KingVision and the C-MAC videolaryngoscopes. Therefore, either of the two positions could be used with these types of videolaryngoscopes, if deemed advantageous for the patient., (© 2018 The Association of Anaesthetists of Great Britain and Ireland.)

In patients with cervical spine injuries, emergence from anesthesia and tracheal extubation can prove as challenging to the anesthesiologist as the tracheal intubation. We report a case of a patient with a potentially unstable cervical spine injury who presented for a nonspinal surgery and experienced agitation on emergence from anesthesia. The use of an intravenous sedative was necessary to ensure cervical spine immobilization but was complicated by severe respiratory depression and the need for reintubation and admission to intensive care. The case report is followed by a review of literature relating to safe extubation of patients with cervical spine injuries. Possible complications during emergence and various methods to prevent these complications are discussed.

Background: The 'classical' technique of rapid sequence induction (RSI) of anaesthesia was described in 1970. With the introduction of new drugs and equipment in recent years, a wide variation in this technique has been used. The role of cricoid pressure is controversial because of the lack of scientific evidence. Moreover, gentle mask ventilation has been recommended in situations such as obesity and critically ill patients, to prevent hypoxaemia during the apnoeic period. In identifying multiple techniques, we conducted a national postal survey to establish the current practice of RSI in the UK., Methods: A survey consisting of 17 questions was created and posted to 255 National Health Service (NHS) hospitals in the UK. We included two copies of the questionnaire in each envelope; one to be completed by the airway lead (consultant anaesthetist with responsibility of overseeing the standard of airway training and implementing national airway guidelines and recommendations within their institution) and the other by a trainee in the same department. The difference in responses from consultants and trainees were assessed using the χ(2) test and the Fisher's exact test., Results: In total we received 272 responses (response rate 53%) of which 266 (58% from consultants and 42% from trainees) were analysed. A majority of the respondents (68%) pre-oxygenated by monitoring end-tidal oxygen concentration and 76% of the respondents use 20-25° head up tilt for all RSIs. Propofol is the most commonly used induction agent (64% of all respondents). Opioid has been used by 80% of respondents and only 18% of respondents use suxamethonium for all patients and others choose rocuronium or suxamethonium based on clinical situation. Although 92% of anaesthetists use cricoid pressure, 83% of them never objectively measure the force used. During the apnoeic period 17% of the respondents use gentle mask ventilation., Conclusions: Our survey demonstrated a persistent variation in the practice of RSI amongst the anaesthetists in the UK. The 'classical' technique of RSI is now seldom used. Therefore there is a clear need for developing consistent guidelines for the practice of RSI., (© The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)