Analysis of Tube-to-Tubesheet Welding in Carbon Steel Heat Exchangers of a Double Plate Header Box

The rear wall of the header box serves as a tubesheet in heat exchangers of double plate header box. Tube-to-tubesheet welding must be performed using orbital Gas Tungsten Arc Welding (GTAW) with a head extension, which is passed through the corresponding hole in the front wall (plugsheet) of the header box, where the welding machine is supported. In this project, the effect of parallelism deviations between the plugsheet and the tubesheet of carbon steel header box is analyzed to evaluate its influence on the quality of the tube-to-tubesheet welding. Welded tube (SA-210 Gr. A1) to tubesheet (SA-516 Gr. 70) coupons are manufactured simulating the parallelism deviations previously analyzed in two double plate header boxes of air-cooled heat exchangers using two different preheating temperatures. Macrographic analysis is performed in order to evaluate the weld penetration (minimum leak path) and length of the weld leg in tube-to-tubesheet joints. The results obtained show important variations in those parameters when the parallelism deviations are equal to or greater than −1 mm over the theoretical distance as well as when the distance approaches +1 mm or more. Finally, the incorporation of dimensional controls prior to the welding process is discussed and the implementation of improvements in orbital GTAW equipment is recommended as an optimal solution for this kind of heat exchangers.

Effect of Progressive Head Extension Swallowing Exercise on Lingual Strength in the Elderly: A Randomized Controlled Trial

Lingual strengthening training can improve the swallowing function in older adults, but the optimal method is unclear. We investigated the effects of a new progressive resistance exercise in the elderly by comparing with a conventional isometric tongue strengthening exercise. Twenty-nine participants were divided into two groups randomly. One group performed forceful swallow of 2 mL of water every 10 s for 20 min, and a total of 120 swallowing tasks per session at 80% angle of maximum head extension. The other group performed five repetitions in 24 sets with a 30 s rest, and the target level was settled at 80% of one repetition maximum using the Iowa Oral Performance Instrument (IOPI). A total of 12 sessions were carried out by both groups over a 4-week period. Blinded measurements (for maximum lingual isometric pressure and peak pressure during swallowing) were obtained using IOPI before exercise and at four weeks in both groups. After four weeks, both groups showed a significant improvement in lingual strength involving both isometric and swallowing tasks. However, there was no significant difference between the groups in strength increase involving both tasks. Regardless of the manner, tongue-strengthening exercises substantially improved lingual pressure in the elderly with equal effect.

Lumbar Roll Usage While Sitting Reduces the Forward Head Posture in Healthy Individuals: A Systematic Review with Meta-Analysis

This systematic review and meta-analysis investigated whether the use of a lumbar roll reduced forward head posture (FHP) while sitting among individuals with or without musculoskeletal disorders. EMBASE, MEDLINE, and the Cochrane Library were systematically searched from their inception to August 2020. The quality of evidence for variables used in the meta-analysis was determined using the GRADE system. Five studies satisfied the criteria for data analysis. All studies included individuals without any spinal symptoms. Data from five studies on neck angle showed a statistically significant (p = 0.02) overall effect (standardized mean difference (SMD) = 0.77), indicating a lesser neck flexion angle while sitting with a lumbar roll than without it. Data from two studies on head angle showed a statistically significant (p = 0.04) overall effect (SMD = 0.47), indicating a lesser head extension angle while sitting with a lumbar roll than without it. In each meta-analysis, the quality of evidence was very low in the GRADE system. The use of a lumbar roll while sitting reduced FHP among individuals without spinal symptoms.

Comparative Analysis of Regional versus General Anesthesia

The administration of regional or general anesthesia is dependent upon many factors to help reduce complications and improve patient outcomes after surgery. In this comparative analysis, the advantages and disadvantages of both types of anesthesia as well as their respective contraindications are reviewed. Both regional and general anesthetics come with adverse effects including morbidity/mortality, and a certain threshold that warrants a type of anesthesia suitable for a surgical procedure. Although there are risks associated with both, certain patient populations may be at higher risk of complications including the elderly, severely ill, and individuals with specific medical conditions. A review of current literature advises the following factors to be examined prior to choosing an anesthesia method most appropriate for the patient including: body mass index (BMI), medical history, age, current medications, fasting time, alcohol/drug intake, pharmaceutical drug use, dental work and airway inspection, as well as neck flexibility and head extension. The research suggests that the patient be fully informed of the risks and benefits of both regional and general anesthesia, as well as taking part in the decision-making process.

Evaluation of Intubating Conditions during Direct Laryngoscopy using Sniffing Position and Simple Head Extension- A Randomised Clinical Trial

Introduction: Optimal laryngeal visualisation during direct laryngoscopy requires adequate positioning of the head and neck. Traditionally, Sniffing Position (SP) is the recommended position to provide superior glottic visualisation. However various studies in recent past have challenged the superiority of SP. Aim: To evaluate whether SP provides better glottic visualisation and ease of intubation {as assessed by total Intubation Difficulty Score (IDS) score as well as its individual components} compared to Simple Head Extension (SHE) during direct laryngoscopy and endotracheal intubation. Materials and Methods: The randomised clinical trial was conducted at GGS Medical College and Hospital, Faridkot, Punjab, India, from May 2019 to October 2020, on 220 patients. Patients undergoing elective surgeries under general anaesthesia were randomly divided into two groups. Laryngoscopy and tracheal intubation in Group I was done in SP, which was obtained by placing a non compressible pillow of height 8 cm under the patient’s head. Patients in Group II underwent laryngoscopy and tracheal intubation in SHE position. Glottic visualisation using modified Cormack and Lehane (CL) grades, IDS and sympathetic responses between the two groups were studied. The data was compared using student’s t-test and Chi-square test. Results: Cormack and Lehane Grade I was seen in 69 (62.7%) of patients in Group I as against 51(46.4%) of patients in Group II (p-value=0.015). Easy intubation (total IDS score=0) was seen in a greater number of patients in Group I (60.9%) as compared to Group II (40.95%) (p-value=0.003). Slight difficulty in intubation (total IDS score=1-5) was encountered in 50.0% of patients in group II (n=55) and 35.5% of patients in group I (n=39) (p-value=0.029). Conclusion: The present study concluded that use of SP resulted in better glottic visualisation and was associated with favourable intubation conditions as compared to SHE position.

Constraints of Load and Posture on Coordination Variability and Marksmanship Performance

The purpose of this study was to assess the establishment of dynamic marksmanship performance under different load and postural configurations. Participants quickly established two postures (forward and high targets) under head, trunk, and extremity loads during marksmanship performance. With the dynamic establishment of posture, load disrupted coordinative dynamics, resulting in reduced speed and accuracy on target. Specifically, torso loads increased segmental variability while establishing posture, and smaller head and upper extremity loads extended quieting time before firing. Increased head extension at the high target further destabilized posture, with reduced accuracy across all loads. Large torso loads reduced the adaptability to modulate postural fluctuations at the foot center of pressure while establishing postures for marksmanship, as evidenced by reductions in center of pressure variability. This study expands traditional static marksmanship research, providing insight into relations between task performance, coordinative variability, and postural control while dynamically establishing precision postures.

Postural control in male ten-pin bowlers of different level of competitiveness

Ten-pin bowling is considered a highly skilled recreational activity with players demonstrating various anthropometric and physiological characteristics. The purpose of the current study was to assess both static and dynamic body balance, in ten-pin bowlers of different level of competitiveness. Thirty four ten-pin bowlers who competed at a high (Level-A, n=17) and a lower level (Level-B, n=17) as well as eighteen individuals without experience in ten-pin bowling (Non-bowlers) participated in the study. Static balance was determined based on the anteroposterior (APd) and mediolateral displacement (MLd) of the center-of-foot-pressure (CoP) that was recorded during single-leg-stance with open and close eyes as well as with open eyes and head extension. Dynamic balance was determined based on the APd and MLd of CoP as well as the normalized distances reached during execution of the Star Excursion Balance Test (SEBT) in the posterior, posterolateral and lateral directions. Significantly better dynamic balance, in terms of the distances reached during SEBT execution, was demonstrated by Level-A bowlers compared to Level-B bowlers and Non-bowlers. The differences between groups regarding APd and MLd, during both static and dynamic balance testing, were in general not significant. Our findings revealed that ten-pin bowlers who compete at a higher level demonstrate better dynamic balance ability. Sports scientists and coaches should be aware of these differences to optimize performance or distinguish ten-pin bowlers with different level of competitiveness.