Influence of automobile seat lumbar support prominence on spine and pelvic postures: a radiological investigation

Background

The use of lumbar supports has been associated with decreased reports of low back pain during driving exposures. However, there has been limited work investigating whether lumbar supports actually change spine and pelvic postures at the level of the vertebrae.

Purpose

To investigate the effectiveness of a lumbar support in changing radiological measures of lumbar spine and pelvic postures and to examine the impact of support excursion magnitudes on these postures.

Methods

Eight male subjects were recruited with no history of back injury, pathologies or low back pain within the past 6 months. Radiographs were taken in four postures: standing, and sitting with 0 cm, 2 cm and 4 cm lumbar support prominence (LSP).

Results

Lumbar lordosis angle increased from 20° with no support to 25° with 2 cm support and 30° with 4 cm support. Lumbar lordosis angles were significantly different between 0 cm support and 4 cm support (p < 0.0001) and between 2 cm support and 4 cm support (p = 0.0256). Increasing lumbar support reduced the flexion at intervertebral disc joints throughout the lumbar spine, however, these remained significantly different from upright standing (p > 0.001) with the exception of L1/L2 in 4 cm support (p = 0.1381) and L5/S1 for all seated postures (p = 0.0687). All measures of pelvic posture were significantly different in sitting compared to standing (p < 0.0001), however, the lumbar support had no significant impact on seated pelvic posture.

Conclusions

Lumbar supports were shown to impact the vertebral rotations of the lumbar spine yet had no effect on pelvis postures. Increasing support from the current maximum of 2 cm–4 cm resulted in increased lumbar lordosis. The changes were mostly imparted at the upper lumbar spine joints with the most marked change being exhibited at the approximate level of the lumbar support apex: in the L2/L3 joint.     

Assessing the ergonomic exposures for drywall workers

Objective

The study was conducted to assess the ergonomic exposures to risk factors that may lead to the reported musculoskeletal injuries (especially back, neck and wrist injuries) of drywall workers.

Methods

A hierarchical taxonomy for construction of drywall panel hanging (drywall panel fitting and installation) was developed with activities defined within the interior wall systems tasks (drywall panel, studs and insulation). Exposures were characterized for the drywall panel work with the PATH (Posture, Activity, Tools, and Handling) work-sampling observation method. Data on working postures were collected for three main body parts: legs, arms and trunk. Activities performed for each task, tools used, and manually handled loads were also recorded for each observation.

Results

The study identified several ergonomic exposures in interior systems construction. Several risk factors were especially prevalent in the drywall panel installation task: awkward body postures such as overhead arm posture, trunk flexion, and handling of heavy drywall panels. Some tasks were observed to have combinations of these musculoskeletal risk factors, such as drywall panel installation, where the workers lifted heavy drywall panels in awkward body postures. In addition, a safety hazard frequently resulted when a worker's foot was poorly supported on a ladder while lifting heavy drywall panels to hang them on the ceiling or upper wall.

Conclusion

The drywall panel installation task poses a severe threat to the safety and musculoskeletal health of the drywall workers. Much of this could be eliminated by reducing the burden of handling heavy and bulky drywall panels.

Relevance to industry

The construction industry is well-documented to have high rates of injury and musculoskeletal disorders. Design of appropriate interventions requires specific knowledge of which tasks and activities involve the highest levels of exposure to relevant factors. Assessment of such factors in drywall panel hanging has provided data that will be useful to evaluate the ergonomics efficacy of future changes in task processes or tools. Feasible solutions appear to exist; effectiveness trials and worker input are needed in order to evaluate whether they could eliminate the observed exposures.     

Successful implementation of user-centered game based learning in higher education: An example from civil engineering

Goal

The use of an online game for learning in higher education aims to make complex theoretical knowledge more approachable. Permanent repetition will lead to a more in-depth learning.

Objective

To gain insight into whether and to what extent, online games have the potential to contribute to student learning in higher education.

Experimental setting

The online game was used for the first time during a lecture on Structural Concrete at Master’s level, involving 121 seventh semester students.

Methods

Pre-test/post-test experimental control group design with questionnaires and an independent online evaluation.

Results

The minimum learning result of playing the game was equal to that achieved with traditional methods. A factor called “joy” was introduced, according to [Nielsen, J. (2002): User empowerment and the fun factor. In Jakob Nielsen’s Alertbox, July 7, 2002. Available from http://www.useit.com/alertbox/20020707.html.], which was amazingly high.

Conclusion

The experimental findings support the efficacy of game playing. Students enjoyed this kind of e-learning.     

Nomophobia: Dependency on virtual environments or social phobia?

Background

The increasing use of new technologies and virtual communication involving personal computers (PCs), tablets and mobile phones are causing changes in individuals’ daily habits and behavior. We report the case of an individual with social phobia who developed a dependency on communication through virtual environments (i.e., nomophobia), and used a PC as a form of relating to the outside world to reduce stress and to avoid direct social relations. Nomophobia refers to the discomfort or anxiety caused by the non-availability of a mobile phone, PC or any another virtual communication device. Social phobia is described as an anxiety disorder of chronic evolution.

Objective

To study nomophobia as a manifest behavior that might serve as an indication of a possible anxiety disorder.

Methodology

The treatment consisted of the use of medication, cognitive-behavioral therapy (CBT) and the application of evaluation tools (interviews, scales, inventories and questionnaires).

Results

The individual responded satisfactorily to medication and CBT treatment, which reduced his time using the PC and increased his exposure to real-life situations.

Conclusion

Nomophobic behavior produces changes in daily habits and can reveal other aspects to be investigated, such as the presence of comorbid mental disorders.     

Who benefits from simulator training: Personality and heart rate variability in relation to situation awareness during navigation training

Objective

This study tested the relationship between individual differences and Situation Awareness (SA) during training in a navigation simulator.

Background

Simulators have become an important tool in the training and education of maritime personnel with a view to improving decisions and performance. There are a few, inconclusive empirical studies that have focused on mapping personality characteristics and their link to the ability to generate and maintain SA during simulator training.

Method

Thirty-six first-year students from the Royal Norwegian Navy Officer Candidate School participated in the study. SA was measured using both subjective and observer ratings.

Results

The results indicated that low scores on Neuroticism and high scores on Extraversion and Conscientiousness (resilient personality type) predicted both subjective and observer-rated SA. Furthermore, participants with high SA were able to modulate their Heart Rate Variability (HRV), with suppression of HRV during navigation training as well showing recovery of HRV.

Application

The potential applications of this research include the assessment of personality differences as a tool in selecting navigators, and the use of HRV as an objective index of adaptability to environmental demands.     

Infection risk in patients with rheumatoid arthritis treated with etanercept or adalimumab

Objectives

To compare the risk of infection for rheumatoid arthritis (RA) patients who took etanercept or adalimumab medication in a nationwide population.

Methods

RA patients who took etanercept or adalimumab were identified in the Taiwan's National Health Insurance Research Database. The composite outcome of serious infections, including hospitalization for infection, reception of an antimicrobial injection, and tuberculosis were followed for 365 days. A Kaplan–Meier survival curve with a log-rank test and Cox proportional hazards regression were used to compare risks of infection between the two cohorts of tumor necrosis factor (TNF)-α antagonists users. Hazard ratios (HRs) were obtained and adjusted with propensity scores and clinical factors. Sensitivity analyses and subgroup analyses were also performed.

Results

In total, 1660 incident etanercept users and 484 incident adalimumab users were eligible for the analysis. The unadjusted HR for infection of the etanercept users was significantly higher than that of the adalimumab users (HR: 1.93; 95% confidence interval (CI): 1.09–3.42; p = 0.024). The HRs were 2.04 (95% CI: 1.14–3.65; p = 0.016) and 2.02 (95% CI: 1.13–3.61; p = 0.018) after adjusting for propensity scores and for propensity scores in addition to clinical factors, respectively. The subgroup analyses revealed that HRs for composite infection was significantly higher in patient subgroups of older age, female, as well as patients who did not have DM, COPD, and hospitalization history at the baseline.

Conclusion

In this head-to-head cohort study involving a nationwide population of patients with RA, etanercept users demonstrated a higher risk of infection than adalimumab users. Results of this study suggest the possible existence of an intra-class difference in infection risk among TNF-α antagonists.     

The relationship between usage intention and adoption of electronic health records at primary care clinics

Objective

Despite of emerging evidence that electronic health records (EHRs) can improve the clinical quality, enhances patient safety and efficiency. Most physicians in primary health care clinics in the Taiwan do not currently adopt EHR at their clinic practices. We aim to measure the relationship between usage intention and adoption behavior.

Study design and methods

We used structured questionnaires distributed both EHRs adopter and non-adopter group to the primary health care physicians which participated in the DOH project to establish the information exchange environment across Taiwan. The response rate of adopter and non-adopter is 54.7% and 55.0% respectively.

Measurements

EHRs adoption behavior.

Results

The EHRs adopter group has higher intention than non-adopter (p = 0.003). From the result of logistic regression analyses, we found the key factors affecting physicians’ adoption pattern were intention to use (OR: 2.85; 95% CI: 2.30–3.54). In addition, higher perceived usefulness (OR: 1.29; 95% CI: 1.06–1.56) and perceived ease to use (OR: 1.48; 95% CI: 1.22–1.79) increase adoption of EHR found.

Conclusion

The intention to use EHR, perceived usefulness and ease to use of primary care physicians were found as key factors influencing EHRs adoption. Thus, we suggest that government should promote the potential benefits of EHR and enhance physicians’ willingness to adopt the EHRs at their clinic practices.     

A study of cyclic dependencies on defect profile of software components

Background

Empirical evidence shows that dependency cycles among software components are pervasive in real-life software systems, although such cycles are known to be detrimental to software quality attributes such as understandability, testability, reusability, build-ability and maintainability.

Research goals

Can the use of extended object-oriented metrics make us better understand the relationships among cyclic related components and their defect-proneness?

Approach

First, we extend such metrics to mine and classify software components into two groups – the cyclic and the non-cyclic ones. Next, we have performed an empirical study of six software applications. Using standard statistical tests on four different hypotheses, we have determined the significance of the defect profiles of both groups.

Results

Our results show that most defects and defective components are concentrated in cyclic-dependent components, either directly or indirectly.

Discussion and conclusion

These results have important implications for software maintenance and system testing. By identifying the most defect-prone set in a software system, it is possible to effectively allocate testing resources in a cost efficient manner. Based on these results, we demonstrate how additional structural properties could be collected to understand component's defect proneness and aid decision process in refactoring defect-prone cyclic related components.     

FMS™ scores and low-back loading during lifting – Whole-body movement screening as an ergonomic tool?

Background

Previous research suggests that a general whole-body movement screen could be used to identify personal movement attributes that promote potentially injurious low-back loading patterns at work. The purpose of this study was to examine the relationship between Functional Movement Screen™ (FMS) composite scores and the low-back loading response to lifting.

Methods

Fifteen men who scored greater than 14 on the FMS (high-scorers) and 15 height- and weight-matched low-scorers (FMS < 14) performed sagittally symmetric and asymmetric laboratory-based lifting tasks. A three-dimensional dynamic biomechanical model was used to calculate peak low-back loading levels, and the angle of the lumbar spine was captured at the instant when the peak compressive force was applied.

Results

Regardless of the lifting task performed, there were no differences in peak low-back compression (p ≥ 0.4157), anterior/posterior reaction shear (p ≥ 0.5645), or medial/lateral reaction shear (p ≥ 0.2581) forces between the high- and low-scorers. At the instant when peak compressive forces were applied, differences in the lumbar spine angle between high- and low-scores were not statistically significant about the lateral bend (p ≥ 0.4215), axial twist (p ≥ 0.2734), or flexion/extension (p ≥ 0.1354) axes, but there was a tendency for the lumbar spine to be more deviated in the low-scorers.

Conclusions

Using the previously established injury prediction threshold value of 14, the composite FMS score was not related to the peak low-back loading magnitudes in lifting. Though not statistically significant, the tendency for the lumbar spines of low-scorers to be more deviated when the peak low-back compression force was imposed could be biomechanically meaningful because spinal load tolerance varies with posture. Future attempts to modify or reinterpret FMS scoring are warranted given that several previous studies have revealed links between composite FMS scores and musculoskeletal complaints.     

A web-based learning tool improves student performance in statistics: A randomized masked trial

Background

e-status is a web-based tool able to generate different statistical exercises and to provide immediate feedback to students’ answers. Although the use of Information and Communication Technologies (ICTs) is becoming widespread in undergraduate education, there are few experimental studies evaluating its effects on learning.

Method

All of the students (121) from an introductory course for statistics in dentistry were randomly assigned to use the tool with one of two 6-problem sets, known as types A and B. The primary endpoint was the grade difference obtained in the final exam, composed of two blocks of questions related to types A and B. The exam evaluator was masked to the intervention group.

Results

We found that the effect of e-status on the student grade was an improvement of 0.48 points (95% CI: 0.10–0.86) on a ten-point scale. Among the 94 students who actually employed e-status, the effect size was 0.63 (95% CI: 0.17–1.10).

Conclusions

It is feasible to formally assess the learning effect of an innovative tool. Providing e-status exercises to students has a direct effect on learning numerical operations related to statistics. Further effects on higher cognitive levels still have to be explored.     

Influence of wearing an unstable shoe on thigh and leg muscle activity and venous response in upright standing

Purpose

To quantify the effect of unstable shoe wearing on muscle activity and haemodynamic response during standing.

Methods

Thirty volunteers were divided into 2 groups: the experimental group wore an unstable shoe for 8 weeks, while the control group used a conventional shoe for the same period. Muscle activity of the medial gastrocnemius, tibialis anterior, rectus femoris and biceps femoris and venous circulation were assessed in quiet standing with the unstable shoe and barefoot.

Results

In the first measurement there was an increase in medial gastrocnemius activity in all volunteers while wearing the unstable shoe. On the other hand, after wearing the unstable shoe for eight weeks these differences were not verified. Venous return increased in subjects wearing the unstable shoe before and after training.

Conclusions

The unstable shoe produced changes in electromyographic characteristics which were advantageous for venous circulation even after training accommodation by the neuromuscular system.     

A theoretical model of dentinogenesis: Dentin and dentinal tubule formation

Introduction

Dentinogenesis, odontoblast dentin formation, includes dentinal growth, mineralization and dentinal tubule formation. Odontoblasts synthesize collagen resulting in collagen apposition contributing to dentinogenesis. Furthermore, within the tubule, they express non-collagenous proteins, such as dentin phosphoprotein (DPP), associated with hydroxyapatite crystal formation and growth. The aim of this work was to determine patterns of growth and dentin formation and quantification of its mineralization. Findings from our work are relevant to endodontics for future regenerative treatment.

Methods

We formulated a 3D domain mathematical model, which recreates the events that lead to dentinal tubule mineralization. As reference we used collagen apposition and DPP activity.

Results

We obtained a model depicting predentin's mineralization distribution during dentin development. Furthermore, we verified different DPP diffusion coefficients to test the model's sensitivity.

Conclusions

We present a model to shed light on the process of dentin and dentinal tubule formation, and its relation to diffusion and mineralization processes.     

On the reliability of mapping studies in software engineering

Background

Systematic literature reviews and systematic mapping studies are becoming increasingly common in software engineering, and hence it becomes even more important to better understand the reliability of such studies.

Objective

This paper presents a study of two systematic mapping studies to evaluate the reliability of mapping studies and point out some challenges related to this type of study in software engineering.

Method

The research is based on an in-depth case study of two published mapping studies on software product line testing.

Results

We found that despite the fact that the two studies are addressing the same topic, there are quite a number of differences when it comes to papers included and in terms of classification of the papers included in the two mapping studies.

Conclusions

From this we conclude that although mapping studies are important, their reliability cannot simply be taken for granted. Based on the findings we also provide four conjectures that further research has to address to make secondary studies (systematic mapping studies and systematic literature reviews) even more valuable to both researchers and practitioners.     

Exploring physical exposures and identifying high-risk work tasks within the floor layer trade

Introduction

Floor layers have high rates of musculoskeletal disorders yet few studies have examined their work exposures. This study used observational methods to describe physical exposures within floor laying tasks.

Methods

We analyzed 45 videos from 32 floor layers using Multimedia-Video Task Analysis software to determine the time in task, forces, postures, and repetitive hand movements for installation of four common flooring materials. We used the WISHA checklists to define exposure thresholds.

Results

Most workers (91%) met the caution threshold for one or more exposures. Workers showed high exposures in multiple body parts with variability in exposures across tasks and for different materials. Prolonged exposures were seen for kneeling, poor neck and low back postures, and intermittent but frequent hand grip forces.

Conclusions

Floor layers experience prolonged awkward postures and high force physical exposures in multiple body parts, which probably contribute to their high rates of musculoskeletal disorders.     

Code smells as system-level indicators of maintainability: An empirical study

Context

Code smells are manifestations of design flaws that can degrade code maintainability. So far, no research has investigated if these indicators are useful for conducting system-level maintainability evaluations.

Aim

The research in this paper investigates the potential of code smells to reflect system-level indicators of maintainability.

Method

We evaluated four medium-sized Java systems using code smells and compared the results against previous evaluations on the same systems based on expert judgment and the Chidamber and Kemerer suite of metrics. The systems were maintained over a period of up to 4 weeks. During maintenance, effort (person-hours) and number of defects were measured to validate the different evaluation approaches.

Results

Most code smells are strongly influenced by size; consequently code smells are not good indicators for comparing the maintainability of systems differing greatly in size. Also, from the comparison of the different evaluation approaches, expert judgment was found as the most accurate and flexible since it considered effects due to the system's size and complexity and could adapt to different maintenance scenarios.

Conclusion

Code smell approaches show promise as indicators of the need for maintenance in a way that other purely metric-based approaches lack.     

A field intervention examining the impact of an office ergonomics training and a highly adjustable chair on visual symptoms in a public sector organization

Objective

Examine the effect of a multi-component office ergonomics intervention on visual symptom reductions.

Methods

Office workers were assigned to either a group receiving a highly adjustable chair with office ergonomics training (CWT), a training-only group (TO) or a control group (C). A work environment and health questionnaire was administered 2 and 1 month(s) pre-intervention and 3, 6, and 12 months post-intervention. Multi-level statistical models tested hypotheses.

Results

The CWT intervention lowered daily visual symptoms (p < 0.01) post-intervention. The TO group did not significantly differ from the control group. The CWT group differed significantly from the TO group (p = 0.01) post-intervention.

Conclusion

Workers who received a highly adjustable chair and office ergonomics training had reduced visual symptoms and the effect was maintained through twelve months post-intervention. The lack of a training-only group effect supports implementing training in conjunction with the highly adjustable chair to reduce visual symptoms.     

Machine learning-based assessment tool for imbalance and vestibular dysfunction with virtual reality rehabilitation system

Background and objective

Dizziness is a major consequence of imbalance and vestibular dysfunction. Compared to surgery and drug treatments, balance training is non-invasive and more desired. However, training exercises are usually tedious and the assessment tool is insufficient to diagnose patient's severity rapidly.

Methods

An interactive virtual reality (VR) game-based rehabilitation program that adopted Cawthorne–Cooksey exercises, and a sensor-based measuring system were introduced. To verify the therapeutic effect, a clinical experiment with 48 patients and 36 normal subjects was conducted. Quantified balance indices were measured and analyzed by statistical tools and a Support Vector Machine (SVM) classifier.

Results

In terms of balance indices, patients who completed the training process are progressed and the difference between normal subjects and patients is obvious.

Conclusions

Further analysis by SVM classifier show that the accuracy of recognizing the differences between patients and normal subject is feasible, and these results can be used to evaluate patients’ severity and make rapid assessment.