Effect Of Position Research Articles

Incidence of Subsequent Injuries Associated with a New Diagnosis of Benign Paroxysmal Positional Vertigo and Effects of Treatment: A Nationwide Cohort Study.

Background/Objectives: Benign paroxysmal positional vertigo (BPPV) is the most common cause of recurrent vertigo and the most common peripheral vestibular disorder. It is characterized by intense vertigo triggered by head and position changes. This study investigates the risk of subsequent injury in BPPV patients and the effects of treatment. Methods: A population-based retrospective cohort study was conducted using data from the Longitudinal Health Insurance Database 2005 in Taiwan. Patients with and without BPPV were identified between 2000 and 2017. The study outcomes were diagnoses of all-cause injuries. The Kaplan-Meier method determined the cumulative incidence rates of injury in both cohorts, and a log-rank test analyzed the differences. Cox proportional hazard models calculated each cohort's 18-year hazard ratios (HRs). Results: We enrolled 50,675 patients with newly diagnosed BPPV and 202,700 matched individuals without BPPV. During follow-up, 47,636 patients were diagnosed with injuries (13,215 from the BPPV cohort and 34,421 from the non-BPPV cohort). The adjusted HR for injury in BPPV patients was 2.63 (95% CI, 2.49-2.88). Subgroup analysis showed an increased incidence of unintentional and intentional injuries in BPPV patients (aHR 2.86; 95% CI, 2.70-3.13 and 1.10; 95% CI, 1.04-1.21, respectively). A positive dose-response relationship was observed with increasing BPPV diagnoses. Treatment with canalith repositioning therapy (CRT) or medications reduced the risk of injury slightly but not significantly (aHR, 0.78; 95% CI, 0.37-1.29, 0.88; 95% CI, 0.40-1.40, respectively). Conclusions: BPPV is independently associated with an increased risk of injuries. CRT or medications have limited effects on mitigating this risk. Physicians should advise BPPV patients to take precautions to prevent injuries even after treatment.

Fetal endocrine axes mRNA expression levels are related to sex and intrauterine position

BackgroundThe hypothalamic–pituitary–adrenal (HPA) and -gonadal (HPG) axes are two major pathways that connect the neural and endocrine systems in vertebrates. Factors such as prenatal stress and maternal exposure to exogenous steroids have been shown to affect these pathways during fetal development. Another less studied factor is the transfer of hormones across fetuses in multifetal pregnancies. This form of transfer has been shown to influence the morphology, anatomy, physiology, and behavior of the offspring in litter-bearing mammals, an influence termed the intrauterine position (IUP) effect. In this study, we sought to delineate how the IUP effects HPA and HPG brain receptors, peptides, and enzymes (hereafter components) in utero and how these influences may differ between males and females.MethodsWe utilized the unconventional model of culled free-ranging nutria (Myocastor coypus), with its large natural variation. We collected brain tissues from nutria fetuses and quantified the expression of key HPA and HPG components in three brain regions: prefrontal cortex, hypothalamus, and striatum.ResultsWe found an interaction between sex and IUP in the mineralocorticoid receptor (MR), gonadotropin-releasing hormone receptor (GNRHR), androgen receptor (AR), and estrogen receptor alpha (ESR1). IUP was significant in both gonadotropin-releasing hormone (GnRH) and its receptor GNRHR, but in different ways. In the hypothalamus, fetuses adjacent to same-sex neighbors had higher expression of GnRH than fetuses neighboring the opposite sex. Conversely, in the cortex, GNRHR exhibited the inverse pattern, and fetuses that were neighboring the opposite sex had higher expression levels than those neighboring the same sex. Regardless of IUP, in most components that showed significant sex differences, female fetuses had higher mRNA expression levels than male fetuses. We also found that HPA and HPG components were highly related in the early stages of gestation, and that there was an interaction between sex and developmental stage. In the early stages of pregnancy, female component expression levels were more correlated than males’, but in the last trimester of pregnancy, male components were more related to each other than female’s.ConclusionsThis study suggests that there are sexually different mechanisms to regulate the HPA and HPG axes during fetal development. Higher mRNA expression levels of endocrine axes components may be a mechanism to help females cope with prolonged androgen exposure over a long gestational period. Additionally, these findings suggest different coordination requirements of male and female endocrine axes during stages of fetal development.

Using the load distribution between girders to monitor the condition of bridges

This study looks at the load distribution among beams in a 3-dimensional bridge Finite Element Model under normal traffic loading and the resulting effect of damage, modelled as a localised loss of elements in a beam. The load distribution is captured, both transversely across the girders and also longitudinally along the girders, and used to identify damage that is remote from the strain sensor location. When there is a loss of elements in a section of the bridge (e.g. due to a strike from a vehicle passing underneath), a portion of the load will redistribute along alternative load paths in the structure. This is most pronounced when the position of the loading and the location of the damage align but also happens when they do not. The study examines the effect of vehicles of different weight and axle configuration on the load distribution, and how grouping results by axle configuration can overcome this. A further novelty of this approach is that the strain response can be transformed into an influence line, which then allows data from large populations of general traffic to be used irrespective of axle configuration. The effect of various transverse positions of vehicles within the driving lane is overcome by combining data from large populations of vehicles. An advantage of this method is that the load distribution from a vehicle crossing is calculated as a ratio i.e. when the bridge is experiencing the same general environmental conditions, and thus reducing the difficulty in controlling the effects of varying environmental conditions when comparing results to a healthy baseline.

Effect of Tongue Position on Facial Morphology of Pakistani Adults and Different Growth Patterns.

To determine the effect of tongue position on facial morphology of Pakistani adults and different growth patterns. Cross-sectional study. Place and Duration of the Study:Department of Orthodontics, Karachi Medical and Dental College, Karachi, Pakistan, from January to April 2021. The study included individuals aged 17 to 30 years with no history of prior orthodontic treatment, absence of wound, burn, or scar tissue in the neck region, comfortable breathing through the nose, absence of deglutition disorder, and a skeletal Class I or II relationship. The exclusion criteria were a cleft lip or palate, or a history of chronic mouth breathing, snoring, or tonsillectomy. According to their skeletal relationships, the subjects were split into three groups; Group I (low-angle), Group II (normal growth), and Group III (high-angle). Vertical growth pattern was assessed on radiograph by interpreting the values of NS / ML (nasion-sella / mandibular plane) angle, and angle formed between FH / ML (Frankfort horizontal plane / mandibular plane). A predesigned proforma was used to record all the measurements made on pre-treatment lateral cephalograms by the sole investigator. Data were analysed using SPSS 24.0. Data from the lateral cephalogram of 79 patients, consisting of 18 (22.8%) males and 61 (77.2%) femaleswho met the inclusion criteria, were analysed.The sample included 15 low-angle, 45 normal vertical growth, and 19 high-angle cases. Fifty participants had Class I skeletal relationships, while 29 had Class II relationships. According to the ANOVA test, FH / ML and NS / ML measurements showed no statistically significant variations in tongue position and growth trends. There was no statistically significant difference between tongue position and facial morphology of Class I or II subjects with different vertical growth patterns. However, there was a statistically sufficient evidence showing the tongue height was greater in Class I skeletal relationship patients as compared to Class II skeletal cases (p = 0.008). Tongue position, Tongue space, Tongue length, Growth pattern.

Effect of Sagittal Root Position, Angle, and Bone Thickness on Peri-implant Tissue Phenotype and Bone Level in Socket Shield Technique: A Retrospective Case Series.

There were only a few studies investigating the effect of sagittal root position (SRP), sagittal root angle (SRA), and buccal bone thickness (BBT) on peri-implant tissues using the socket shield technique (SST). This retrospective case series aimed to evaluate the SRP, SRA, and BBT in socket shield cases and examine the effect of these anatomical factors on the peri-implant tissue phenotype and bone level. Data from 27 patients (14 women, 13 men) treated with SST in the maxillary esthetic region between July 2019 and September 2021 were included. Clinical indices (modified plaque and bleeding indices, probing depth, keratinized mucosa width, mucosal thickness) and periapical radiographic recordings (marginal bone level) taken immediately after permanent prosthesis placement and 1 year later were used. Cone beam computerized tomography images were used to examine BBT, SRP, and SRA before implant placement and horizontal and vertical bone levels before implant placement and 1 year after prosthetic rehabilitation. The data were divided into groups based on BBT (<1 and ≥1 mm) and SRA values (<10° and ≥10°). There were no significant differences in 1-year clinical factors between the SRA <10° and SRA ≥10° groups. However, higher vertical bone loss was found in the SRA ≥10° group (P = .01, d = 0.53). There were no significant differences in clinical or radiographic factors between the BBT <1 mm and BBT ≥1 mm groups. In conclusion, BBT showed no significant effect on tissue phenotype and bone level, but SRA affected bone level in socket shield cases.

The effect of Position and Availability interventions on adolescents’ food choice: An online experimental study

The effect of Position and Availability interventions on adolescents’ food choice: An online experimental study

Effect of posture on position of subcutaneous implantable cardioverter-defibrillator

BackgroundThe PRAETORIAN score was developed as an alternative for defibrillation testing after subcutaneous implantable cardioverter-defibrillator implantation to assess 3 aspects of implant position on a bidirectional chest radiograph. The score is validated on a standard standing chest radiograph with arms elevated in the lateral view. ObjectiveWe aimed to evaluate the effect of different anatomic positions on the PRAETORIAN score. MethodsThirty patients with a subcutaneous implantable cardioverter-defibrillator underwent standard posterior-anterior and lateral chest radiography, including additional lateral views in 2 positions: standing with arms down and supine with arms alongside the body. PRAETORIAN score and weighted κ coefficient were calculated for each position. ResultsIn 8 of 30 patients, the PRAETORIAN score was ≥90 in standard position. The agreement in PRAETORIAN score was substantial (κ = 0.677) for the position with the arms down and fair (κ = 0.399) for the supine position. With the arms down, the PRAETORIAN score decreased in 10 patients (33%), 4 of whom changed to a lower risk category. In supine position, the PRAETORIAN score decreased in 16 patients (53%), 7 of whom changed to a lower risk category, 1 from high to low risk. ConclusionA supine or arms-down position during chest radiography can result in lower PRAETORIAN scores and underestimation of associated risk on defibrillation testing failure. This emphasizes the importance of correct anatomic positioning (arms up) during chest radiography when the PRAETORIAN score is used.

A Study on the Effects of Different Positions on the Clinical Prognosis of Patients with Acute Ischemic Stroke.

The key to treating Acute Ischemic Stroke (AIS) is to rapidly reopen occluded blood vessels, restore blood flow, and rescue the ischemic penumbra. Treatment methods mainly include thrombolysis, endovascular intervention, etc. However, these treatments are limited by strict time windows and technical conditions. Simpler and more feasible methods to improve cerebral blood flow are currently a hot topic in clinical research. In recent years, several studies have shown that changes in body position can effectively improve cerebral blood flow in patients. However, the effect on the neurological functional prognosis of AIS remains inconclusive. This review has examined the effects of changes in body position on the clinical prognosis of AIS, combining relevant guidelines and the latest research. The study has provided evidence of an improvement in the clinical prognosis of AIS.

Effect of the prone position on mechanical power in elective surgical patients under general anesthesia: A prospective observational study.

To evaluate how the prone position influences mechanical power (MP) during elective surgical procedures. In this prospective study carried out at Karadeniz Ereğli Government Hospital, Zonguldak, Turkey, from January 2024 to February 2024, 76 patients under general anesthesia were evaluated at different time points during the surgical procedure. Hemodynamic, laboratory, and mechanical ventilation data were also recorded. The MP increased in the prone position at the beginning of surgery. Transitioning to the supine position at the end of surgery led to a decrease in MP. At the end of surgery, the mean MP in supine and prone positions was found to be higher compared to those measured in the first hour of surgery. Mechanical power and body mass index (BMI) exhibited a significant positive correlation. Position changes influence MP. Returning to the prone position increases MP. An increase in BMI is associated with an increase in MP.ANZCTR Reg. No.: ACTRN12623001281684.

Effect of Strain Relief Loop Position on the RF-Induced Heating of Active Implantable Medical Devices at 1.5-T MRI

Effect of Strain Relief Loop Position on the RF-Induced Heating of Active Implantable Medical Devices at 1.5-T MRI

Theoretical study on the effect of different positions of -CN group on photophysical properties and forward-reverse ESIPT behaviours of 2,5-bis(benzo[d]thiazol-2-yl)phenol derivatives

Excited state intramolecular proton transfer (ESIPT) compounds have been widely used in many fields due to its unique photophysical properties, but they are strongly affected by substituents. There are many studies on the effect of substituents at the same position on the ESIPT process, but there are few studies on the effects of substituents at different positions on the proton transfer process. In this work, a strong electron-withdrawing cyano group ( – CN) was introduced into different positions of 2,5-bis(benzo[d]thiazol-2-yl)phenol. The effect of different substituted positions on intramolecular hydrogen bond (IHB), photophysical properties and forward-reverse energy barrier of ESIPT reaction have been systematically investigated adopting density functional theory (DFT) and time-dependent DFT. The result showed that the introduction of – CN group at different positions led to a slight red-shift of absorption, and intramolecular charger transfer is the intrinsic reason for this photophysical phenomenon. The position of – CN group obviously influenced the excited state IHB, and then had an effect on ESIPT process. The substitution positions in the left benzo[d]thiazole ring and phenol ring respectively hinder and promote the ESIPT process, while the substitution in the right benzo[d]thiazole ring not only impetus the ESIPT process, but also increase the tautomer fluorescence.

Effect of Over-the-Rotor Liner on Fan Flutter Stability

Previously published literature has proved excellent performance of the over-the-rotor acoustic liner (OTRL) in noise reduction. This work investigates the impact of the OTRL on fan flutter stability in a subsonic duct using a three-dimensional coupled singularity method. The effects of the axial position and the acoustic impedance of the liner on the fan flutter stability are examined. Results show significant near-field coupling between the acoustic liner and the rotor, affecting the unsteady blade loading distributions and intensifying as the liner and the rotor overlap axially. The fan flutter stability shows clear sensitivity to the liner’s acoustic resistance, while its dependency on acoustic reactance appears more complex. An energy-based analysis shows that secondary unsteady loading induced by rotor–OTRL interaction may inverse the phase of the total unsteady loading, thus affecting the fan flutter stability.

Effect of substituent position on assembly of compounds bearing ortho/para over meta directing groups

This research investigated the impact of substituent location on intermolecular interactions and crystal packing. A class of N-(dichlorophenyl)-2-pyrazincarboxamide derivatives were synthesized and characterized: 2,5-dichloro (2,5-diCl), 3,4-dichloro (3,4-diCl), and 2,4-dichloro (2,4-diCl). Comparison with their monochloro counterparts (2-chloro (2-Cl), 3-chloro (3-Cl), and 4-chloro (4-Cl)) revealed a distinct structural variation upon introducing a second chlorine substituent at the ortho/para positions of the phenyl ring. Conversely, incorporating a second chlorine atom at the meta position resulted in similar molecular packing. These findings suggest that ortho/para directing groups play a dominant role in dictating the crystal assemblies of the studied compounds.

Effect of void size and position on mechanical properties of nanotwinned metals under cyclic loading

Effect of void size and position on mechanical properties of nanotwinned metals under cyclic loading

The Effects of Positive Psychological Capital on Innovative Behavior and Turnover Intention of the Start-ups employees: Focused on the Moderating Effects of Gender and Job Position

The Effects of Positive Psychological Capital on Innovative Behavior and Turnover Intention of the Start-ups employees: Focused on the Moderating Effects of Gender and Job Position

Hybrid algorithm GA-PSO-BP in secure localization technology for wireless sensor networks

ABSTRACT Wireless sensors face problems such as poor positioning accuracy in their applications. A hybrid indoor space safety positioning technology is proposed for this purpose. This technology uses genetic models and particle swarm optimization models to optimize the parameters of neural networks. Considering the vulnerability of wireless sensors to Sybil attacks during the positioning process, communication encryption and location awareness are used for optimization. In the positioning experiment, the proposed method had maximum positioning errors of 0.23 m and 0.43 m on the first and second floors, respectively, which were superior to other methods. In the positioning security experiment, the positioning errors of the first and second floors after being attacked by Sybil were 4 m and 5 m respectively, while the proposed security positioning technology had an error range of 1 m. In terms of security comparison, when there are 31–35 attack samples, the proposed method has a maximum root mean square error and average absolute error of 0.72 m and 0.79 m, respectively, which is superior to other models. It can be seen that the proposed technology has excellent positioning effect and stability. The research content will provide important technical support for the practical deployment and security management of wireless sensor networks.

Numerical simulation study on the effect of ignition position on premixed hydrogen deflagration characteristics in tunnels

To analyze the influence of different ignition positions on the propagation of deflagration characteristics and the disaster mechanism in the hydrogen deflagration process in the tunnel, this study compares and verifies the experimental data of tunnel model deflagration based on the CFD code GASFLOW-MPI. A combustion velocity model based on the accelerated separation effect is used, and the effect of heat transfer on the consequences of deflagration is considered. The propagation laws of pressure waves, fluid velocity and temperature in the tunnel are analyzed, and it is found that the changing trends of shock waves and fluid velocity in the tunnel are consistent, but completely opposite in the tunnel outside. The effects of different ignition positions on the hydrogen deflagration characteristics are compared and analyzed. The results show that when ignition occurs at different heights of the center of the premixed region, the impact on the deflagration characteristics is relatively small, while when ignition occurs at different horizontal distances in the premixed region, the impact on the deflagration characteristics is relatively large; the peak overpressure of side ignition is far lower than the case where ignition occurs in the center of the premixed region, but the maximum flow velocity is much higher than the center ignition. The impact on temperature is the smallest. In general, in areas close to the hydrogen/air premixed zone, side ignition results in more severe consequences, whereas in areas far from the premixed zone and outside the tunnel, central ignition leads to more severe consequences. This study provides theoretical support for understanding the disaster-causing mechanisms of hydrogen/air premixed gas deflagration in tunnels under different ignition positions.

Effect of Stem Design and Positioning on the Leg Axis after Total Hip Arthroplasty: A Secondary Analysis.

Background/Objectives: Various parameters, like femoral offset and leg length, are associated with good patient outcomes after total hip arthroplasty. In this prospective study, the effects of stem design, its placement in the proximal femur and the resulting femoral offset on the total leg axis were investigated. Methods: The 27 patients included in this study received biplanar radiography (EOS®, EOS Imaging) with 3D reconstruction using sterEOS® both preoperatively and postoperatively. For all leg alignment parameters obtained from the 3D reconstruction and from measurements using mediCAD, the deltas between the postoperative and preoperative values were determined. Patients were divided into those who received a short-stem prosthesis and those who received a straight-stem prosthesis. Results: The change in femoral offset with the implantation of a short-stem prosthesis was significantly greater than that with the implantation of a straight-stem prosthesis (11.4 ± 5.9 vs. 4.6 ± 7.4 mm, p = 0.014). Compared with the straight-stem implantation, short-stem implantation caused a significantly greater increase in the varus orientation of the leg (-1.4 ± 0.9 vs. -0.4 ± 1.4°, p = 0.048). There was no significant difference in the positioning of the short-stem prosthesis compared to the straight-stem prosthesis in the proximal femur (3.6 ± 3.1 vs. 2.6 ± 1.9°, p = 0.317). Conclusions: These findings substantiate the impact of prosthesis design on offset and leg alignment. The implantation of short-stems is more variable and requires precise planning. Intraoperative non-physiological offset changes and varus deviation of the leg axis should be avoided. Trial registration: This study was retrospectively registered with the German Clinical Trials Register (DRKS) under the number DRKS00015053 on the 1 August 2018.

Comparison of the Effectiveness Lateral Position 30 Degrees and 90 Degrees on Decubitus Events in Stroke Patients

Aims: Stroke is the second leading cause of death and disability globally, characterized by sudden neurological deficits. Pressure ulcers, caused by prolonged bed rest, can be managed non-pharmacologically through immobilization and routine tilting to prevent decubitus. To compare the effectiveness of the lateral position with an inclination of 30 and 90 degrees on the risk of decubitus in stroke patients, in this study the control group was tilted 90 degrees and the intervention group was tilted 30 degrees. Method: The sampling method is non-probability sampling with purposive sampling, a sample of 22 patients. Results: Data analysis using Reapeted Measurement Anova resulted in a value in the experimental group resulting in a sum of square value of 24.9, f value 14.3, P &lt; 0.001, while in the control group a sum of square value of 76.5, f value 26.8, P &lt; 0.001 was obtained, so it can be concluded that the lateral position with an inclination of 90 degrees and 30 degrees has the same effect, namely providing a significant influence on reducing the risk of decubitus. Conclusions: The study reveals that stroke patients aged 56-65 have a higher risk of pressure ulcers, with low-weight patients at higher risk. Early lateral position intervention and nutrition can significantly reduce the risk of decubitus, highlighting the importance of early wound healing.

Association between operative position and postoperative nausea and vomiting in patients undergoing laparoscopic sleeve gastrectomy.

Bariatric surgery is one of the most effective ways to treat morbid obesity, and postoperative nausea and vomiting (PONV) is one of the common complications after bariatric surgery. At present, the mechanism of the high incidence of PONV after weight-loss surgery has not been clearly explained, and this study aims to investigate the effect of surgical position on PONV in patients undergoing bariatric surgery. To explore the effect of the operative position during bariatric surgery on PONV. Data from obese patients, who underwent laparoscopic sleeve gastrectomy (LSG) in the authors' hospital between June 2020 and February 2022 were divided into 2 groups and retrospectively analyzed. Multivariable logistic regression analysis and the t-test were used to study the influence of operative position on PONV. There were 15 cases of PONV in the supine split-leg group (incidence rate, 50%) and 11 in the supine group (incidence rate, 36.7%) (P = 0.297). The mean operative duration in the supine split-leg group was 168.23 ± 46.24 minutes and 140.60 ± 32.256 minutes in the supine group (P < 0.05). Multivariate analysis revealed that operative position was not an independent risk factor for PONV (odds ratio = 1.192, 95% confidence interval: 0.376-3.778, P = 0.766). Operative position during LSG may affect PONV; however, the difference in the incidence of PONV was not statistically significant. Operative position should be carefully considered for obese patients before surgery.