Flat Position Research Articles

Exploring optimal sampling strategy of testate amoebae as hydrological bioindicators in UK upland peatlands

Many modified or degraded blanket bogs in the UK have been undergoing restoration by different rewetting strategies. While testate amoebae (TA), well-known as hydrology-sensitive species, have been increasingly applied to assess and monitor peatland restoration success, we still do not know the most appropriate sampling strategy of TA in heather-dominated peatlands. In this study, TA communities were taken from two modified blanket bog sites and one intact border mire across a strong hydrological gradient to explore the optimal sampling strategy. The results showed that: 1) TA communities from Sphagnum moss performed better to indicate the hydrological gradient of peatland habitats than other plant types (i.e., other mosses, heather and sedge litter), among which the dominant and second abundant Sphagnum moss species had similar performance as combined all Sphagnum moss did; 2) there was a clear and marked vertical separation in TA community composition, living status and species-specific niche preference; and 3) TA species richness and density incrementally increased from March to next January although median species richness decreased from September to the following January; by contrast, the average number of encysted TA was much higher in June and January than in March and September, which highlights the capability of TA to form cysts in response to extreme hot/dry and cold weather and this change may also suggest a non-negligible influence on ecosystem processes (e.g., C-cycling). Considering sampling cost and practicality, this study in heather-dominated peatlands recommends sampling the entire segment/length of the dominant Sphagnum moss from relatively flat (lawn) positions (although more studies are needed for microtopographic investigation) during the autumn or early winter as a simple but effective sampling strategy to assess the potential of TA as hydrological bioindicators or when using them to monitor the restoration (rewetting) success.

Analysis Welding Types Pipe Fabrication Process in Missile Fast Attack Boat Construction

The equipment in the piping system consists of pipes, valves, flanges, filters, fittings, pumps, and others. The installation schedule for this piping system begins after the connection between blocks. Pipes as part of a ship's system have several steps in their installation procedure, one of which is welding. Welding on pipes is carried out by professional welders who have met more complex competency requirements than welders in general, such as flat position welders, vertical welders, or overhead welders. The purpose of this study was to determine the welding process and types of welding in pipe fabrication for the construction of the Missile Fast Attack Boat. Result comparison between the diameters of the welded pipes, the greater the value of the welding volume formed. The largest volume is 426 mm3, with a pipe length for the fabrication process of 4,3 m. On the other hand, the shortest fabrication is for welding pipes with a diameter of 2,5 m, which has a volume of 127 mm3. While the welding process using GTAW / Gas Tungsten Arc Welding (TIG) is very appropriate for welding in small areas and thin pipes. The TIG welding process has an average volume of below 150 mm3.

An animated education program to reduce anxiety, vascular complications, and flat time among children undergoing cardiac catheterization: A randomized control trial, study protocol

One of the most dangerous and prevalent birth disorders is congenital heart defects (CHD). Children diagnosed with CHD may need many operations or medical treatments throughout their lives, including cardiac catheterization (CC). Children undergoing CC experience elevated levels of anxiety. Elevated levels of anxiety among children undergoing CC can be harmful to children physiologically, psychologically, and behaviorally. Additionally, vascular complications such as bleeding and hematoma represented the majority of complications among children undergoing CC. To achieve positive management outcomes, nurses must use an effective method to prepare children for CC. This study present the protocol for developing and implementing an animated education program (AEP) about CC on anxiety, vascular complications, and flat time among children undergoing CC for the first time. A Parallel Randomized Control Trial (RCT) design will be utilized to test the study hypotheses. It is an experimental design where participants are assigned randomly to either receive an intervention or not, and the outcome of interest is then evaluated after the intervention to assess its impact. The trial had been registered as Clinical Trails.gov PRS (Protocol Registration and Result system) Identifier: Protocol ID 101271-6 and clinical trials.gov ID (NCT06483087) under the brief title: Effect of Animated Education on Anxiety and Vascular Complications (VAEda) ClinicalTrials.gov Protocol Registration and Results System (PRS). A random sample of 98 children scheduled for a CC, whose ages range from 6 to 12 years old, will be recruited from a military hospital for medical and surgical heart disease in Jordan, with 49 children in the intervention group and 45 children in the control group. Children in the control group will receive routine care. However, children in the experimental group will receive an AEP, an 8-minute carton animated video that illustrates pediatric CC. The animated cartoon video was developed in Arabic using age-appropriate information. The study’s intervention is intended to give adequate information to children to prepare them for the events occurring before, during, and after the CC procedure, it will be presented to the intervention group 24 hours before the procedure. Outcome measures include anxiety levels that will be assessed 2 hours before children undergo CC. Bleeding and hematoma at the CC site will be assessed 2 hours postsheath removal, and flat time will be assessed by recording the hours that the child stays in a flat position postsheath removal. This exploratory experiment is a necessary first step in investigating important components of a full-scale clinical study. This study presents a novel technique designed for children undergoing CC to lower their anxiety, vascular complications, and flat time. The results of the current study provide evidence-based data that can improve nursing practice and research in pediatric cardiac nursing. Create a policy that emphasizes the critical role that nurses play in delivering high-quality health education through the use of AEP.

Application of fallout radionuclide—137Cs for estimating soil erosion in steep hillslopes with diverse land use of North-western Indian Himalayas

Hilly and mountainous regions are significantly impacted by soil erosion, primarily due to rainfall-runoff processes occurring on the hillslope scale. Assessing soil erosion is crucial for quantifying the loss of soil carbon and nutrients, which diminishes the potential of soil ecosystem services and is critical for mitigating the impacts of climate change on food security. However, the Himalayan landscape poses serious challenges for assessing soil erosion due to its steep and rugged terrain, which hinders the use of conventional and modelling methods. The fallout radionuclide—137Cs has been extensively utilized as an environmental marker for investigating soil redistribution processes. Despite its potential, there is a notable lack of 137Cs-based soil erosion studies in the Himalayan region. In this context, we assessed the applicability of the fallout radionuclide—137Cs method in quantifying soil erosion rates and identifying erosion hotspots on two hillslopes of the Higher Himalayas. On the hillslope scale, we observed that soil erosion rates vary based on slope gradient and land use/land cover. Forested areas exhibited the lowest soil erosion rates compared to cultivated areas, while flat hillslope positions experienced lower erosion rates than steeper positions. The average net erosion rate for the Harsil hillslope varied among different hillslope positions, ranging from – 2.9 to – 15.6 t ha−1 yr−1. Similarly, in the Gangnani hillslope, the net erosion rates varied across different positions, ranging from – 5.6 to – 39 t ha−1 yr−1. Our findings confirm that the middle and lower hillslope positions are the most critical source areas with higher soil erosion rates, while hillslope positions with forest cover demonstrate the lowest erosion rates, identified as helpful in controlling soil erosion. The study has demonstrated the applicability of FRN as a soil erosion measurement method in the complex, rugged, and steep terrain of the Himalayas, highlighting the need for targeted conservation efforts to mitigate soil erosion and preserve ecosystem integrity.

Fluid distribution during surgery in the flat recumbent, Trendelenburg, and the reverse Trendelenburg body positions.

The distribution and elimination of infused crystalloid fluid is known to be affected by general anesthesia, but it is unclear whether changes differ depending on whether the patient is operated in the flat recumbent position, the Trendelenburg ("legs up") position, or the reverse Trendelenburg ("head up") position. Retrospective data on hemodilution and urine output obtained during and after infusion of 1-2 L of Ringer's solution over 30-60 min were collected from 61 patients undergoing surgery under general anesthesia and 106 volunteers matched with respect to the infusion volume and infusion time. Parameters describing fluid distribution in the anesthetized and awake subjects were compared by population volume kinetic analysis. General anesthesia decreased the rate constant for urine output by 79% (flat recumbent), 91% (legs up) and 91% (head up), suggesting that laparoscopic surgery per se intensified the already strong anesthesia-induced fluid retention. General anesthesia also decreased the rate constant governing the return of the distributed fluid to the plasma by 32%, 15%, and 70%, respectively. These results agree with laboratory data showing a depressive effect of anesthetic drugs on lymphatic pumping, and further suggest that the "legs up" position facilitates lymphatic flow, whereas the "head up" position slows this flow. Both Trendelenburg positions increased swelling of the "third fluid space". General anesthesia caused retention of infused fluid with preferential distribution to the extravascular space. Both Trendelenburg positions had a modifying influence on the kinetic adaptations that agreed with the gravitational forces inflicted by tilting to body.

Perioperative infusion of magnesium sulfate versus dexmedetomidine on the hemodynamic responses in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial

Background: Laparoscopic cholecystectomy is associated with less post-operative pain, shorter hospitalization, and a faster functional recovery as compared to the open procedure. However, like any other surgery, a stress response is induced. Anesthesia interventions such as direct laryngoscopy, tracheal intubation, and extubation involve severe sympathetic stimulation. Magnesium can block the release of catecholamines from both the adrenal gland and adrenergic nerve terminals by inhibiting of activation of membrane Ca²⁺-ATPase and Na⁺-K⁺-ATPase. Aims and Objectives: Both magnesium sulfate and dexmedetomidine decrease the release of catecholamines and attenuate pressor responses to anesthesia and surgery. Materials and Methods: Eighty-four ASA I/II patients were randomly allocated to two groups. Group D received dexmedetomidine 1 μg/kg followed by 0.4 μg/kg/h and Group M received 2 g MgSO₄ followed by 15 mg/kg/h. hemodynamic variables were recorded as T0 (after loading dose of study drug), just before (T1) and 1, 2, and 3 min after ProSeal laryngeal mask airway (PLMA) insertion (T2 [i] [ii] [iii]), before and after peritoneal insufflation (T3 and T4), before and after table tilt (T5 and T6), after resuming flat position (T7), peritoneal deflation (T8), PLMA removal (T9), and on post-anesthesia care unit admission (T10). Data were collected and analyzed using SPSS 17 statistical software. Results: The demographic profile was comparable. After the study drug administration, there was a fall in mean arterial pressure (MAP) in both groups (Group D > Group M) and no pressor response to PLMA insertion. At peritoneal insufflation, the MAP increase was significantly more in Group M at T6, T7, and T8 (31.9%, 27.9%, and 35.6% above baseline, respectively). Although there was a fall in systolic blood pressure (SBP) from the baseline throughout the procedure in both groups, SBP was significantly higher at most times in Group M as compared to Group D (P<0.05). In both groups, there was a similar rise in diastolic blood pressure after peritoneal insufflation. The mean heart rate was significantly lower in Group D at all time points. Conclusion: Dexmedetomidine seemed to be superior to MgSO₄ for ameliorating hemodynamic responses in patients undergoing laparoscopic cholecystectomy.

Submerged arc welding process: enhancement of production performance based on metallurgical observations

Welding processes are widely used technologies in the industrial context for creating permanent connections between mechanical components. This popularity is due to their versatility, which arises from the numerous available process variants and the multiple advantages they offer compared to other joining techniques. In the manufacturing context, where devices often operate in extreme conditions, the quality of welds becomes a critical factor in ensuring the safety and reliability of the manufactured products. Furthermore, a sound joint requires careful compliance with the increasingly stringent design specifications demanded by customers who require industry-standard conformity in order to achieve defect-free, robust, and durable welds. To address these needs and to define the optimal roadmap for the investigated process condition, an experimental investigation was conducted on the submerged arc welding process. The experimental trials involved butt joints of ASTM A516 Gr.70 carbon steel plates with different thicknesses in a flat position, utilizing a U-shaped chamfer and a multi-pass welding technique. For each weldment, the effects of the main process parameters on the qualitative characteristics of the manufactured products were evaluated from a metallurgical perspective. This evaluation included an in-depth metallographic analysis of the heat-affected zone of the carbon steel joint and involved both the measurement of the dimensions of these areas as well as the amount of ferrite and pearlite that resulted as the phases observed in the final microstructure of the steel joint following its solidification. Furthermore, the joint quality was assessed with regard to mechanical strength through hardness measurements. By analysing the experimental data, the paper provides a valuable contribution for increasing the productivity of the investigated welding process, while simultaneously meeting the specified industrial quality requirements for the products made of medium-thickness carbon steels.

Active decompression during automated head-up cardiopulmonary resuscitation

BackgroundThe combination of active compression-decompression cardiopulmonary resuscitation (ACD-CPR) with an impedance threshold device (ITD) and controlled head-up positioning (AHUP-CPR) is associated with improved outcomes compared with conventional CPR (C-CPR). This study focused on the role of active decompression (AD) during AHUP-CPR. MethodsFarm pigs (n = 10, ∼40 kg) were anesthetized, intubated and ventilated. Physiological parameters and right ventricular pressure–volume loops were recorded continuously. Ventricular fibrillation was induced and left untreated for 10 mins, followed by automated C-CPR (2 min), ACD + ITD CPR in the flat position (2 min), and then AHUP-CPR with 3 cm of lift above the neutral chest position. After 15 min of CPR, AD was discontinued and then restarted incrementally to 4 cm. Data were analyzed with a linear mixed-effects model, using random intercepts for individual pigs. ResultsUpon cessation of AD during AHUP-CPR, decompression right atrial pressure (+59%) increased (p < 0.01), whereas multiple hemodynamic parameters positively associated with perfusion, including coronary (−25%) and cerebral perfusion pressures (−11%), end-tidal CO2 (−13%), stroke volume and cardiac output (−26%), decreased immediately and significantly with p < 0.05. Restoration of AD reduced right atrial pressure and increased positive perfusion parameters in an incremental manner. Only with ≥ 3 cm of AD were all hemodynamic parameters restored to ≥ 90% of pre-AD discontinuation levels. ConclusionFull chest wall lift, achieved with ≥ 3 cm of AD, was needed to maintain and optimize hemodynamics during AHUP-CPR in pigs. These findings should be considered when optimizing care with this new approach.

Influence of welding parameters on the formation of U-rib fillet welds in single-sided welding of steel bridge panels

It is difficult to reach the requirement of 80% U-rib weld penetration in the practical application of single-sided welding of steel bridge panels. Meanwhile, full penetration has to be avoided. In this study, efforts are made in order to achieve fillet welds with 80% and above penetration consistently. The effect of welding parameters on the formation of single-sided U-rib fillet welds is investigated. This work has revealed that U-rib fillet weld penetration is presenting an upward trend as the welding current increases under specific welding conditions, and full penetration was observed at the current of 325 A. With the increasing distance between the filler wire and the root of the weld, the U-rib penetration reduces. As the torch angle increases during ship position welding, the U-rib penetration will first increase and then decrease. The weld formation of flat position welding is more stable and the U-rib weld penetration has been significantly improved. The optimum U-rib weld with penetration of 84.8% is achieved under the conditions of flat position welding with 285 A welding current, 44∘ torch angle, and 2[Formula: see text]mm distance between the wire and the root.

Geodesic structure, shadow and optical appearance of black hole immersed in Chaplygin-like dark fluid

In this study, we focus on a black hole immersed in a cosmological Chaplygin-like dark fluid (CDF), characterized by the equation of state p = -B/ρ and an additional parameter q influencing the energy density of the fluid. We investigate the geodesic structure, shadow, and optical appearance of such a black hole. Through analysis on the effective potential and the epicyclic frequencies, it is found that the existence of innermost/outermost stable circular orbits for a timelike particle is governed by the CDF parameters. The behaviors of the orbital conserved quantities and Keplerian frequency are also examined. Due to the existence of pseudo-cosmological horizon, the determination of the shadow radius depends significantly on the position of the observer. By placing the static observer at an approximately flat position between the event and pseudo-cosmological horizons, we constrain the CDF parameters using EHT observations. We investigate the effect of CDF on the shadows and optical images of the black hole, surrounded by various profiles of accretions. For the thin disk accretion, the light trajectories are categorized into direct emission, lensing ring, and photon ring based on impact parameters. Due to the existence of outermost stable circular orbits, outer edges could exist in the direct and lensing ring images. The observed brightness is mainly due to direct emission, with a minor contribution from the lensing ring, while the contribution from the photon ring is negligible due to extreme demagnetization. In the case of spherical accretion, we consider both static and infalling accretion models. The images obtained under infalling accretion are slightly darker than those under static accretion, attributed to the Doppler effect. Throughout the study, we analyze the influence of the parameters B and q on the results.

Ultra-Compact Orthoplanar Spring via Euler-Spiral Flexures

Orthoplanar springs are single-component compliant mechanisms that can be fabricated from sheet material and undergo deflection orthogonal to the plane of the mechanism. They are useful in applications where spatial constraints are significant. An Euler spiral is a curve whose curvature is linearly proportional to the arc length allowing for the curve to assume a flat position under a load. In this work, orthoplanar spring and Euler-spiral concepts are synthesized to create a single-component spring mechanism that lies flat under a load. Where traditional planar springs under a load will take on an out-of-plane contour, the Euler-spiral orthoplanar spring lies completely flat under a load. The relationship between the load needed to flatten the orthoplanar Euler-spiral spring and its physical geometry is examined. A use case where the Euler-spiral orthoplanar spring is utilized as a deployment mechanism for a mid-flight emerging antenna on the surface of a flight body is presented.

Photocatalytic and biological efficacy of Carissa macrocarpa fruit extract-mediated one-pot synthesized ternary metal oxide dual S-scheme heterojunction

Photodegradation of organic pollutants on the surface of greenly synthesized nanomaterials under sunlight irradiation is a viable approach for water purification. Since a little attention has been paid to the green synthesis of ternary nanocomposites, therefore current work has been designed to greenly synthesized dual S-scheme heterojunction using aqueous extract of Carissa macrocarpa fruit. After successful characterization by UV-Visible spectroscopy (UV-Vis.), Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), scanning electrode microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), high-resolution transmission electron microscopy (HR-TEM), Thermogravimetric analysis (TGA), dynamic light scattering (DLS), and zeta potential analysis (ZP), Thermogravimetric analysis and X-ray photoelectron spectroscopy (XPS), the stable nanocomposite was evaluated for its catalytic potential for the photodegradation of three azo dyes, i.e., methylene blue (MB), Congo red (CR), and methyl orange (MO), under sunlight. 91 %, 97 %, and 85 % degradation with rate constant values of 2.03×10−2 min−1, 2.83×10−2 min−1, and 1.64×10−2 min−1 were observed for MB, CR, and MO, respectively, in just 120 minutes of exposure to sunlight. Effect of radical scavengers and flat band positions of NCs were evaluated to propose the mechanism and transfer of electrons and holes to decompose the dyes. The reusability of the catalyst was assessed for five consecutive cycles, which showed only a slight reduction (∼1.09%) in its activity. In addition to their photocatalytic potential, the aqueous extract and the greenly synthesized nanocomposite were also evaluated for their antibacterial potential by the disc diffusion method.

Vortex-plate interaction in wake-induced vibration: A study of single and parallel flat plates behind a cylinder

This numerical study investigates the wake-induced vibration of single or parallel flat plates mounted in the wake of a circular cylinder in laminar flow. The results highlight the critical role of flat plate positioning, as it influences their ability to act as control mechanisms or experience significant vibrations. For a single plate, mounting outside the critical position initiates large amplitude vibrations, gradually decreasing as the plate moves away from the horizontal axis. Additionally, vibrations with moderate amplitudes are observed at specific short horizontal positions due to variations in the near-wake structure. In the case of parallel plates constrained to vibrate independently, vibrations only occur when there is sufficient space for shear-layer interaction. Different vortex suppression and plate vibration mechanisms are identified by adjusting the vertical gap, where increasing the gap reduces the non-vibrating zone. The study also examines a range of reduced velocities, revealing that although the plate(s) follow the upstream cylinder's shedding frequency in all configurations, this frequency may be affected and altered in short gaps. Comparing single and parallel plates demonstrates their potential for designing energy harvesting systems. However, parallel plates offer a slight advantage due to using independent objects within a relatively identical area.

Reducing the Time Before the Console in Robotic-Assisted Laparoscopic Hysterectomy

Robotic-assisted surgery enables precise manipulations with magnified vision, stereoscopic vision, and forceps with multi-joint functions. It requires unique procedures such as position setting, port placement, roll-in, and docking, which lead to prolonged operation and anesthesia time. Five conditions described below were established at our institution to reduce the time to the initiation of console: (1) changing the patients' position from the flat lithotomy position to the spread legs position; (2) attaching a Hasson cone to hold the umbilical cannula stable; (3) changing the cannula's obturator (inner tube) from blunt to bladeless; (4) fixing the team, and (5) conducting regular docking training. These outcomes were examined in this study. The study included 77 patients who underwent robotic-assisted total hysterectomy for benign uterine disease and stage IA uterine cancer at our individual institution between April 2019 and July 2022. We compared the median time from anesthesia to console initiation between the first half group (cases 1-40) and the second half group (cases 41-77). The former required 91.5 (53-131) minutes, whereas the latter required 59 (37-126) minutes. Appropriate equipment selection and team education can reduce the time to console initiation.

Effect of tools rotational speed on the mechanical properties of one-step double-acting friction stir welded aluminum alloy AA 6061 hollow panel

The utilization of Aluminum hollow panels enhances structural strength while simultaneously ensuring a lightweight and efficient use of materials. During their application, these panels necessitate a welding process that is susceptible to porosity due to the disparity in hydrogen gas solubility between liquid and solid aluminum. Solid-state welding techniques, such as Friction Stir Welding (FSW), have proven to be effective and appropriate solutions for overcoming this issue. However, due to the thickness of the hollow panels, FSW process is unfeasible as it requires welding on both sides, resulting in prolonged production times. Consequently, the development of a one-step double-acting FSW technique becomes necessary, involving the simultaneous utilization of two tools. The usage of two tools introduces two sources of friction-stir forces, heat, and axial forces, demanding an assessment of the novel response from the specimens. This research aims to analyze the effect of a specific parameter, namely the tool rotation speed, within the one-step double-acting FSW process on the physical and mechanical properties of the AA6061 hollow panels. The One-Step Double-Acting FSW process involved conducting variations in the tool rotation speed on both sides of the welds. Specifically, for the 4G weld position (underside of the workpiece with an overhead weld position), speeds of 1200, 1500, and 1800 rpm were employed. Meanwhile, a consistent rotation speed of 1500 rpm was maintained for the 1G weld position (overside of the material with a flat weld position). The transverse speed and tilt angle are set at 30 mm/min and 2°, respectively. Elevating the tool rotation speed results in increased hardness, load capacity, and bending strength of the weld joints. The specimen subjected to the highest rotational speed (1800 rpm) exhibits the most exceptional mechanical properties, including a hardness of 73.46 HVN, load capacity of 18.47 kN, and bending strength of 60.56 MPa.

Evaluation of Surface Hardness of Heat Cure Acrylic Resin Reinforce by Nano Al2O3 After Polishing with Different Materials

The goal of this research was to determine the surface hardness of heat cure acrylic resin reinforced with Nano Al2O3 after polishing with various materials. Materials and methods: - The 70 rectangular samples were made of a pink impact resistant thermoset acrylic (Vertex, Implacryl, The Netherlands) (65mm long x 10mm diameter x 3mm thick). Following polishing with each material (pumice stone, diamond suspension, colloidal silica), the surface roughness of each sample was determined using the Profilometer surface roughness instrument. The sample surface was glued to the profiler's horizontal base in a very flat position, and the stylus (the profiler's needle) was moved across each sample surface three times in three different directions over a distance of 1.7 mm. were separated into (7) groups were determined by the concentration of Nano powder, Group (A) Control without adding Nano filler of (Al2O3) (10) specimens, Group (B) Polishing with pumice Al2O3 (1%) (10) specimens, Group (C) Polishing with pumice Al2O3 (1.5 %) (10) specimens, Group (D) Polishing with Colloidal Al2O3 (1%) (10) specimens, Group (E) Polishing with Colloidal Al2O3 (1.5%) (10) specimens, Group (F) Polishing with Diamond Al2O3 (1%) (10) specimens, and Group (G) Polishing with Diamond Al2O3 (1.5%) (10) specimens. Data were statistically analyzed using statistical package for social science (SPSS), and the (ANOVA) test is used to determine whether the statistical hypothesis is true. Results: - For the hardness readings the higher mean value of hardness test found in group(D) (1%) polished by colloidal silica (82.74), then group (F)(1.5%)polished by colloidal(82.18), then group (F)(1%)polished by diamond( 81.12), then group(G)(1.5%)polished by diamond( 80.62),then group(C)(1.5%)polished with pumice(80.34),then group(B)(1%) polished with pumice(80.2),then at least group (A)control(80.18). Each of the three groups had a statistically significant difference with Highly sign. (P&lt;0.01). Conclusions: -Specimens of acrylic reinforcement with adding 1.5% of Nano AL2O3 and polished with (colloidal silica, diamond suspension, and pumice, respectively) sequentially showed highly surface hardness then

Single pass laser vacuum welding of thick steel plates using electromagnetic support

The increasing demand for renewable energy produced by offshore wind turbines goes along with an increased demand in the production of offshore wind turbine foundations, so called “monopiles”, which are made by joining thick metal sheets. The industrial standard of multi-layer submerged arc welding (SAW) for joining of thick metal sheets is the current bottleneck in the production of monopiles. A possible increase in productivity by the implementation of high-power laser welding in a newly developed mobile vacuum chamber (MoVac) and an electromagnetic root support is the subject of this study. Single run butt welds are performed in flat position on S355 mild steel of thicknesses up to 80 mm using a disc laser system with 1030 nm wavelength and a maximum output of 60 kW. The laser optic is fixed on the MoVac-System which is held and manipulated by an articulated robot.

Evaluation of the Effect of Gluteus Maximus Contraction by Electrical Stimulation on Interfacial Pressure in Supine Bed Positions.

This study investigated the impact of neuromuscular electrical stimulation (NMES) to the gluteus maximus in the bed flat position (F position) and 30-degree head elevation position (30 HE position) on sacral pressure. Twenty volunteers consented to participate in this study. Sacral pressure was measured in the F position and at the 30 HE position with and without NMES in the supine positions. NMES was applied to the gluteus maximus (frequency, 50 Hz; pulse width, 300 μs) with sufficient stimulus intensity to induce muscle contraction. Sacral maximum pressure was determined as peak pressure index (PPI) by averaging the values from the central nine sensors of the maximum pressure zone. The effect of NMES on pressure gradient and the influence of sex difference were also explored. Sacral PPI was significantly lower after NMES implementation in both the F position and the 30 HE position when compared with conditions without NMES (P <0.001). The pressure gradient was also significantly decreased with NMES (P <0.001). Analysis of sex difference in subjects treated with NMES revealed a significantly greater effect on maximum sacral pressure in males than in females. Application of NMES to the gluteus maximus helps to disperse sacral pressure in supine positions. NMES on the gluteus maximus can be a clinical means to manage interfacial pressure in supine positions.

Double Whammy Cases of Severe Mitral Stenosis in Peripartum: A Survival Case Series

Background: Valvular heart disease in pregnancy is still not widely studied. The combination of mitral stenosis and the physiology of pregnancy for both mother and fetus often result in poor hemodynamics, and management during labor and peripartum period greatly determines the prognosis of both lives.Case: A 42 years old G3P2A0 (Case A) and A 33 years old G3P1A1 (Case B) both had a history of previous SC labor, presented worsening shortness of breath since 2nd trimester, coughing and swelling in both legs, also unable to rest in a flat position. especially, case B was frequent re-hospitalized with prolonged LOS during 2nd – the 3rd trimester due to acute lung edema. We found a mid-diastolic murmur grade II/IV at the apex. Electrocardiography (ECG) of case A: sinus rhythm, left atrial enlargement (LAE), while case B: AF rapid response. The echocardiography of case A revealed severe MS, while case B revealed severe MS, moderate tricuspid regurgitation and, a high probability for PH. Those findings support the diagnosis of severe mitral stenosis and rheumatic heart disease in pregnancy, then they were programmed to do balloon mitral valvuloplasty (BMV) in 3rd trimester.Discussion: The BMV was performed, and succeeded in case A reducing the mitral valve pressure gradient (MV PG) from 24.7mmHg to 12.1mmHg by using local anesthesia along the procedure, while in case B specifically done BMV with general anesthesia due to supraventricular tachycardia (SVT) and pulmonal congestive during procedure, reducing the MV PG from 17.7mmHg to 8.6mmHg, as well as improvement in symptoms, up to pregnancy was terminated as obstetric indication by SC on 36-37 weeks' gestation in both cases. The baby born was healthy with weights of each case 2340gr and 2630gr. Conclusion: Mitral stenosis in the peripartum needs to be managed by interprofessional collaboration properly, to decrease the risk of morbidity and mortality for the mother and fetus.

Effect of automated head-thorax elevation during chest compressions on lung ventilation: a model study

Our goal was to investigate the effects of head-thorax elevation (HUP) during chest compressions (CC) on lung ventilation. A prospective study was performed on seven human cadavers. Chest was automatically compressed-decompressed in flat position and during progressive HUP from 18 to 35°. Lung ventilation was measured with electrical impedance tomography. In each cadaver, 5 sequences were randomly performed: one without CC at positive end-expiratory pressure (PEEP) 0cmH2O, 3 s with CC at PEEP0, 5 or 10cmH2O and 1 with CC and an impedance threshold device at PEEP0cmH2O. The minimal-to-maximal change in impedance (VTEIT in arbitrary unit a.u.) and the minimal impedance in every breathing cycle (EELI) the) were compared between flat, 18°, and 35° in each sequence by a mixed-effects model. Values are expressed as median (1st–3rd quartiles). With CC, between flat, 18° and 35° VTEIT decreased at each level of PEEP. It was 12416a.u. (10,689; 14,442), 11,239 (7667; 13,292), and 6457 (4631; 9516), respectively, at PEEP0. The same was true with the impedance threshold device. EELI/VTEIT significantly decreased from − 0.30 (− 0.40; − 0.15) before to − 1.13 (− 1.70; − 0.61) after the CC (P = 0.009). With HUP lung ventilation decreased with CC as compared to flat position. CC are associated with decreased in EELI.