Nucleic acid extraction from complex biofluid using toothpick-actuated over-the-counter medical-grade cotton.

Nucleic acid amplification technique (NAAT)-assisted detection is the primary intervention for pathogen molecular diagnostics. However, NAATs such as quantitative real-time polymerase chain reaction (qPCR) require prior purification or extraction of target nucleic acid from the sample of interest since the latter often contains polymerase inhibitors. Similarly, genetic disease screening is also reliant on the successful extraction of pure patient genomic DNA from the clinical sample. However, such extraction techniques traditionally utilize spin-column techniques that in turn require centralized high-speed centrifuges. This hinders any potential deployment of qPCR- or PCR-like NAAT methods in resource-constrained settings. The development of instrument-free nucleic acid extraction methods, especially those utilizing readily available materials would be of great interest and benefit to NAAT-mediated molecular diagnosis workflows in resource-constrained settings. In this report, we screened medical-grade cotton, a readily available over-the-counter biomaterial to extract genomic DNA (gDNA) spiked in 30 %, 45 %, and 60 % serum or cell lysate. The extraction was carried out in a completely instrument-free manner using cotton and a sterilized toothpick and was completed in 30 min (with using chaotropic salt) or 10 min (without using chaotropic salt). The quality of the extracted DNA was then probed using PCR followed by agarose gel analysis for preliminary validation of the study. The qPCR experiments then quantitatively established the extraction efficiency (0.3-27 %, depending on serum composition). Besides, percent similarity score obtained from the Sanger sequencing experiments probed the feasibility of extracted DNA towards polymerase amplification with fluorescent nucleotide incorporation. Overall, our method demonstrated that DNA extraction could be performed utilizing toothpick-mounted cotton both with or without using a chaotropic salt, albeit with a difference in the quality of the extracted DNA.

Oscillating Transcriptome during Rice-Magnaporthe Interaction.

Rice blast disease caused by the fungus, Magnaporthe oryzae, is one of the most devastating diseases of rice. Deciphering molecular mechanism of host-pathogen interactions is of great importance in devising disease management strategies. Transcription being the first step for gene regulation in eukaryotes, basic understanding of the transcriptome is sine qua non for devising effective management strategy. The availability of genome sequences of rice and M. oryzae has facilitated the process to a large extent. The current review summarizes recent understanding of rice-blast pathosystem, application of transcriptomics approaches to understand the interactions employing different platforms, major determinants in the interaction and possibility of using certain candidate for conditioning enhanced disease resistance (Effector Triggered Immunity and PAMP Triggered Immunity) and downstream signalling in rice. A better understanding of the interaction elements and effective strategies hold potential to reduce yield losses in rice caused by M. oryzae.

Poland syndrome.

Poland's syndrome is a rare congenital condition, characterized by the absence of the sternal or breastbone portion of the pectoralis major muscle, which may be associated with the absence of nearby musculoskeletal structures. We hereby report an 8-year-old boy with typical features of Poland syndrome, the first documented case from Uttar Pradesh, India.

Sentiment Analysis and Comprehensive Evaluation of Supervised Machine Learning Models Using Twitter Data on Russia-Ukraine War.

The Russia-Ukrainian War refers to the ongoing hostilities between Russia and Ukraine. It was first focused on whether Crimea and the Donbass were formally recognised as being a part of Ukraine when Russia started it in February 2014. The conflict dramatically grew when Russia began its incursion of Ukraine on February 24, 2022, following a military build-up on the Russian-Ukrainian border that started in late 2021. Examining public perceptions of the crisis between Russia and Ukraine is the goal of this piece. These days, social media has taken on a significant role in communication, and as a result, opinions can be found on platforms like Facebook, Twitter, and Instagram. The study makes use of his 11,250 tweets about the war between Russia and Ukraine from his Twitter account. Techniques, including image processing, object identification, and natural language processing, have shown application, power, and potential for machine learning. The same applies to text analytics. For text analysis, sentiment analysis, and entity annotation, machine learning techniques are frequently employed. According to the applicability and efficacy of the machine learning model, natural language processing toolkit in python is utilised in to examine the textual polarity and subjectivity score of tweets. Moreover, because machine learning models have a high degree of classification accuracy, they have been widely utilised to categorise emotions. We have developed and test models using three feature extraction techniques: TF-IDF (term frequency-inverse document frequency), BoW (bag of words), and N-gram. Each model was assessed using a number of important performance indicators, including accuracy, precision, recall, and F1 score. Results show that the extra trees classifier (ETC) model achieves a highest accuracy of 0.84 in combination with the Bow property which is a measure to evaluate the efficacy of a machine learning algorithm. Logistic regression (LR), decision tree (DT), support vector machine (SVM), XGB, Gaussian naive base (GNB), ADA, and K-nearest neighbours (KNN) comparison have also been made.

Development of a ZnOS+C Composite as a Potential Adsorbent for the Effective Removal of Fast Green Dye from Real Wastewater.

Wastewater treatment is becoming increasingly important due to the potential shortage of pure drinking water in many parts of the world. Adsorption offers a potential technique for the uptake of contaminants and wastewater purification. In the last two decades, several efforts have been made to remove fast green (FG) dye from wastewater via different adsorbent materials. However, adsorption capacity shown by these adsorbents is low and time-consuming. Herein, we have synthesized for the first time a new powdered adsorbent ZnOS+C, modified zinc peroxide with sulfur and activated carbon to effectively remove FG dye from wastewater. Results of batch adsorption experiments have suggested that ZnOS+C has the maximum adsorption potential of 238.28 mg/g for FG dye within 120 min of adsorption equilibrium for a wide range of pH ranging from 2 to 10 pH. The adsorption process conforms to the Freundlich isotherm model, suggesting a multilayered adsorption process on the outer surface of ZnOS+C. The adsorption kinetics study indicates that the kinetics of the reaction are the intraparticle diffusion model. Briefly, this study shows proof of the application of ZnOS+C powder as a new eco-friendly adsorbent with extremely high efficiency and high surface area for removing FG dye.

Biomechanical loads and subjective stress exposure to lumber graders in sawmill industry.

The aim of this study was to determine biomechanical loads and subjective stresses on lumber graders and associated morbidity in a high risk and repetitive sawmill occupation. The exposures of all 29 male sawmill worker volunteers were recorded. Motion and posture were studied with electrogoniometers, muscle loads were recorded with surface electromyography, and psychophysical stresses were assessed with subjective responses. Fifty-nine percent of the participants reported greater than moderate discomfort in their task-dominant upper extremity. Job performance required an average range of motion of 44°, 21°, and 52° in flexion/extension, radial/ulnar deviations, and pronation/supination respectively. It also required an average of 9% maximum voluntary contraction force and was repeated an average of 34 times/min. This repetitive exertion over an 8-h shift was deemed to be a significant risk factor associated with prevalent upper extremity morbidity.

Fractal dimension and lacunarity analysis of mandibular bone on digital panoramic radiographs of tobacco users.

Background. This study aimed to evaluate and compare changes in the mandibular trabecular bone pattern using the fractal dimension (FD) and lacunarity analysis in tobacco users with healthy controls. Methods. This study was carried out on digital panoramic radiographs of 225 subjects divided into three groups: smokeless tobacco users (SLTs), smokers, and control (n=75). ImageJ program with FracLac plugin was used to assess the FD and lacunarity of mandibular trabecular bone on the digital panoramic radiographs. Results. The differences in the mean FD values of the study and control groups were statistically significant (P < 0.001). Mean FD was lower in the case groups than the control group, with SLTs having the least FD value. A significant difference in lacunarity was noted between SLTs and controls (P < 0.001). On the contrary, there was no significant difference in lacunarity between smokers and controls. Conclusions. FD values were lower in tobacco users, suggesting that tobacco users have a less complex trabecular bone pattern than healthy controls. Higher lacunarity values in SLTs indicated a more heterogeneous bone pattern. These findings signify that FD and lacunarity analysis on digital panoramic radiographs can serve as promising predictive tools to assess bone quality for osteoporotic changes in tobacco users, thereby facilitating prompt referral for further management.

Medication Adherence in Indian Epilepsy Patients.

PURPOSE: While two-thirds of epilepsy patients can become seizure free on medical treatment, poor adherence to medication is a major problem to sustained remission and functional restoration. The aim of this study was to assess the prevalence and associated factors of antiepileptic drug (AED) non-adherence. METHODS: We conducted a subgroup analysis based on results that emerged from a single center, cross-sectional study. Patients who were 18 years or older were included. The 4-item Morisky Medication Adherence Scale was used to measure adherence to AED (s). Multivariable logistic regression analysis was used to predict factors associated with AED non-adherence. RESULTS: A total of 268 patients fulfilled inclusion criteria and were included in this subgroup analysis. Among the participants, 81 (30%) were non-adherent to medication. Three factors associated with non-adherence were AED polytherapy [OR: 4.5 (2.1-9.5) P = 0.001], drug related adverse events [OR: 3.9 (2.1-7.3) P = 0.001], and treatment duration exceeding 3 years [OR: 2.6 (1.3-5.0) P = 0.003]. CONCLUSION: About one-third patients were not compliant with their medication. If the treatment of patients is restricted to monotherapy as far as possible and patients are educated about duration of treatment and possible adverse effects of AEDs, non-adherence may be reduced.

Anterior superior iliac spine asymmetry assessment on a novel pelvic model: an investigation of accuracy and reliability.

OBJECTIVE: The purpose of this study was to develop a novel pelvic model and determine the accuracy and the inter- and intraexaminer reliability of anterior superior iliac spine (ASIS) positional asymmetry assessment from both sides of the model by osteopathic predoctoral fellows and osteopathic physicians and to evaluate the effect of training. METHODS: Five osteopathic predoctoral fellows and 5 osteopathic physicians assessed 13 settings of varied ASIS asymmetry of a novel pelvic model for superior/inferior positional asymmetry from both sides of the model in a random order. Assessment from the right and left sides of the model occurred on 2 separate days. Fellows were trained for a week and retested. RESULTS: Average interexaminer reliability was greatest from the left side of the model for physicians and from the right side for fellows (physicians: kappa = 0.46, fellows: kappa = 0.37), whereas intraexaminer reliability was greatest from the right in both groups (physicians: kappa = 0.49, fellows: kappa = 0.52). Following training of fellows, interexaminer reliability remained highest from the right side of the model (right: kappa = 0.48, left: kappa = 0.36), whereas intraexaminer reliability was higher from the left side (right: kappa = 0.53, left: kappa = 0.59). Physicians and fellows before training were more accurate from the right side of the model (kappa = 0.56 and kappa = 0.52, respectively). Following training of fellows, accuracy increased from both sides of the model (right: kappa = 0.59, left: kappa = 0.53). CONCLUSIONS: A novel pelvic model was developed to allow assessment of accuracy and reliability of ASIS asymmetry assessment. Individually, physicians and fellows varied in accuracy and inter-/intraexaminer reliability. Further investigation is warranted to understand the clinical and educational application of these results.

Comparison of ergonomic risk assessment output in four sawmill jobs.

The objectives of this study were to examine the agreement between 5 ergonomic risk assessment methods calculated on the basis of quantitative exposure measures and to examine the ability of the methods to correctly classify 4 at risk jobs. Surface electromyography and electrogoniometry were used to record the physical exposures of 87 sawmill workers performing 4 repetitive jobs. Five ergonomic risk assessment tools (rapid upper limb assessment [RULA], rapid entire body assessment [REBA], American conference of governmental industrial hygienist's threshold limit value for mono-task hand work [ACGIH TLV], strain index [SI], and concise exposure index [OCRA]) were calculated. Dichotomization of risk to no risk and at risk resulted in high agreement between methods. Percentage of perfect agreement between methods when 3 levels of risk were considered was moderate and varied by job. Of the methods examined, the RULA and SI were best (correct classification rates of 99 and 97% respectively). The quantitative ACGIH-TLV for mono-task hand work and Borg scale were worst (misclassification rates of 86 and 28% respectively).

Cancer Biology and You: An Interactive Learning Event for Native American High School Students to Increase Their Understanding of Cancer Causes, Prevention, and Treatment, and to Foster an Interest in Cancer-Related Careers.

The National Institutes of Health and the National Science Foundation have made a compelling call to action not only to strengthen the pipeline of available STEM-trained talent, but in addition to foster students who are members of populations currently under-represented in science. Furthermore, the scientific community must not only increase the accessibility of STEM-related education, but also implement and test evidence-based practices. Presented here, we detail the proceedings of a hands-on, science-focused informal learning opportunity aimed at educating an underrepresented population in cancer biology. Fifteen undergraduate and graduate student volunteer instructors from the University of Nebraska at Omaha and the University of Nebraska Medical Center engaged with 89 high school students, mostly Native American, in an informal learning event called "Cancer Biology and You Day." Throughout the event, students completed two independent lessons focusing on breast cancer and skin cancer and demonstrated strong learning gains associated with the lessons as assessed by KWL charts. Exit surveys of the students indicated high levels of satisfaction with the event, and positive attitudes associated with considering a career in science/research were evident in survey responses. Overall, we report the event as a success and outline how similar experiences may be achieved.

Comparison of ergonomic risk assessment output in a repetitive sawmill occupation: trim-saw operator.

Multiple ergonomic risk assessment methods of unique structure are currently being used to direct industrial prevention initiatives focused on musculoskeletal injuries. In this study, the physical exposures required to perform an at-risk sawmill occupation were collected from 29 subjects via quantified means (surface electromyography and electrogoniometery) and used to calculate several ergonomic risk assessment methods. The aims of this study are to: 1) compare the output of the RULA, REBA, ACGIH TLV, Strain Index and OCRA ergonomic risk assessment methods, 2) examine the assessments' ability to differentiate between facilities reporting meaningfully different incidence rates, and 3) examine the effect of varying the definition of end range posture and exertion required on risk assessment scores. Risk level output assigned by all methods were not sensitive to inter facility differences in risk of injury, suggesting interpretation of risk index and component scores are needed to direct intervention. Components of all methodologies were sensitive to worker technique and facility assessed. Varying variable definition resulted in significantly different component, combined component and/or risk output scores in all methods assessed. The significant effect of posture and exertion variable definition suggests definitions taken to be interchangeable by work site evaluators are not equivalent.

A comparison of muscular activity involved in the use of two different types of computer mouse.

Two types of computer input devices, a conventional mouse and a roller bar one, were studied in terms of muscular activity in m. trapezius dexter, m. deltoideus anterior dexter and m. extensor digitorum dexter, and comfort rating. Fifteen university students and employees participated in this study. The order of the devices was random. While a task was performed, electromyography (EMG) data were recorded for each test. Muscular activity was found to be significantly lower for the roller bar mouse than for the conventional one. Comfort rating indicated there was a significant difference in moving a cursor with the conventional mouse compared to the roller bar one. It is concluded that a roller bar mouse allowed the subjects to work closer to the body compared to the conventional one, thus the former can be recommended as a general means of reducing upper extremity musculoskeletal disorders.

Are epilepsy patients bypassing primary care? A cross-sectional study from India.

PURPOSE: Lack of epilepsy primary and secondary care and an arbitrary referral system causes many epilepsy patients to seek tertiary care even when they may not need it. This causes overcrowding, increased waiting times and also compromises the quality of tertiary care. We conducted this study to identify what proportion of epilepsy patients presenting to tertiary care actually needed it. METHODS: To test appropriateness of candidacy for tertiary care, we formulated Modified NICE criteria (MNC) based on NICE criteria. Modified NICE criteria were used to dichotomize participants into two groups: a) those who needed tertiary care and b) those who did not need tertiary care. We also looked at agreement between MNC and original NICE criteria. RESULTS: Four hundred and twenty two patients were recruited. According to the MNC, 240 patients (57%) qualified for tertiary care while 182 (43%) did not. The agreement between MNC and original NICE criteria was 86.7%, kappa 0.73(95% CI 0.66-0.79, p < 0.001). The most frequently cited reason for seeking tertiary care was 'Unsatisfactory response to treatment', although; many of these patients were actually non-adherent to treatment. Amongst variables that predicted non-eligibility for tertiary care, the most important was not having been referred. CONCLUSION: Many epilepsy patients seeking tertiary care do not need it. Access and quality of epilepsy care can be improved if there is a rational and need-based distribution of patients between primary, secondary and tertiary care. Referral systems also need to be developed and used to transition patients from one level of care to another.

High Quality Unigenes and Microsatellite Markers from Tissue Specific Transcriptome and Development of a Database in Clusterbean (Cyamopsis tetragonoloba, L. Taub).

Clusterbean (Cyamopsis tetragonoloba L. Taub), is an important industrial, vegetable and forage crop. This crop owes its commercial importance to the presence of guar gum (galactomannans) in its endosperm which is used as a lubricant in a range of industries. Despite its relevance to agriculture and industry, genomic resources available in this crop are limited. Therefore, the present study was undertaken to generate RNA-Seq based transcriptome from leaf, shoot, and flower tissues. A total of 145 million high quality Illumina reads were assembled using Trinity into 127,706 transcripts and 48,007 non-redundant high quality (HQ) unigenes. We annotated 79% unigenes against Plant Genes from the National Center for Biotechnology Information (NCBI), Swiss-Prot, Pfam, gene ontology (GO) and KEGG databases. Among the annotated unigenes, 30,020 were assigned with 116,964 GO terms, 9984 with EC and 6111 with 137 KEGG pathways. At different fragments per kilobase of transcript per millions fragments sequenced (FPKM) levels, genes were found expressed higher in flower tissue followed by shoot and leaf. Additionally, we identified 8687 potential simple sequence repeats (SSRs) with an average frequency of one SSR per 8.75 kb. A total of 28 amplified SSRs in 21 clusterbean genotypes resulted in polymorphism in 13 markers with average polymorphic information content (PIC) of 0.21. We also constructed a database named 'ClustergeneDB' for easy retrieval of unigenes and the microsatellite markers. The tissue specific genes identified and the molecular marker resources developed in this study is expected to aid in genetic improvement of clusterbean for its end use.

Torque and EMG in rotation extension of the torso from pre-rotated and flexed postures.

BACKGROUND: Back injury is a common place in our society. Up to two-thirds of back injuries have been associated with trunk rotation. However, the torque production ability with a rotated spine and electromyographic activity of trunk muscles in such efforts is poorly understood. Therefore, the objectives of this study are to study torque production capacity of variously rotated and flexed trunk and to measure the EMG of selected trunk muscles in these activities. METHODS: Nineteen normal young subjects (7 males and 12 females) were recruited. Subjects were stabilized on a posture-stabilizing platform and were instructed to assume a flexed and right rotated posture (20 degrees , 40 degrees and 60 degrees of rotation and 20 degrees , 40 degrees and 60 degrees of flexion) in a random order. The subjects were asked to exert their maximal voluntary contraction in the asymmetric plane of rotation-extension for a period of 5s. The surface EMG of the external and internal obliques, rectus abdominis, latissimus dorsi, erector spinae at the 10th thoracic and 3rd lumbar vertebral levels was recorded bilaterally along with the torque generated. FINDINGS: Whereas the torque generated was significantly affected by both rotation and extension in both genders (P<0.001), the EMG was independent of rotation but affected by flexion in females only (P<0.01). The torques produced by both genders in each of the nine postures was significantly different from each other (P<0.001). The EMG demonstrated a trend of increase with increasing rotation and flexion. The response surfaces of normalized peak EMG of the right external oblique and internal oblique was somewhat similar, indicating a rotator torque and a stabilizing effect. The left latissimus dorsi and right external oblique provided the rotational torque and the right erector spinae provided the extensor effort. Since the rotation-extension was performed in the plane of asymmetry, the effort required the recruitment of muscles involved in left rotation, stability of rotated spine and an extensor effort. INTERPRETATION: The torque production capacity of the human trunk is posture dependent and declines with increasing rotation. However, with increasing rotation and flexion, the magnitude of EMG increases. This implies that with increasing asymmetry, it requires more muscle effort (thus tissue stress) to generate less torque. Increasing asymmetry tends to weaken the system and may enhance chances of injury.

Analysis of right anterolateral impacts: the effect of trunk flexion on the cervical muscle whiplash response.

BACKGROUND: The cervical muscles are considered a potential site of whiplash injury, and there is a need to understand the cervical muscle response under non-conventional whiplash impact scenarios, including variable body position and impact direction. There is no data, however, on the effect of occupant position on the muscle response to frontal impacts. Therefore, the objective of the study was to measure cervical muscle response to graded right anterolateral impacts. METHODS: Twenty volunteers were subjected to right anterolateral impacts of 4.3, 7.8, 10.6, and 12.8 m/s(2) acceleration with their trunk flexed forward 45 degrees and laterally flexed right or left by 45 degrees. Bilateral EMG of the sternocleidomastoids, trapezii, and splenii capitis and acceleration of the sled, torso, and head were measured. RESULTS AND DISCUSSION: With either direction of trunk flexion at impact, the trapezius EMGs increased with increasing acceleration (p < 0.05). Time to onset of the electromyogram and time to peak electromyogram for most muscles showed a trend towards decreasing with increasing acceleration. With trunk flexion to the left, the left trapezius generated 38% of its maximal voluntary contraction (MVC) EMG, while the right trapezius generated 28% of its MVC EMG. All other muscles generated 25% or less of this measure (25% for the left splenius capitis, 8% for the right splenius capitis, 6% for the left sternocleidomastoid, and 2% for the left sterncleidomastoid). Conversely, with the trunk flexed to the right, the right trapezius generated 44% of its MVC EMG, while the left trapezius generated 31% of this value, and all other muscles generated 20% or less of their MVC EMG (20% for the left splenius capitis, 14% for the right splenius capitis, 4% for both the left and right sternocleidomastoids). CONCLUSION: When the subject sits with trunk flexed out of neutral posture at the time of anterolateral impact, the cervical muscle response is dramatically reduced compared to frontal impacts with the trunk in neutral posture. In the absence of bodily impact, the flexed trunk posture appears to produce a biomechanical response that would decrease the likelihood of cervical muscle injury in low velocity impacts.

The effect of seat belt use on the cervical electromyogram response to whiplash-type impacts.

OBJECTIVE: The objective of this study was to determine the effect of a standard 3-point lap-and-shoulder seat belt and car seat on the electromyogram (EMG) response of the cervical muscles to increasing low-velocity impacts in comparison with that of a rigid seat and 5-point restraint. METHODS: Seventeen healthy volunteers were subjected to rear, frontal, right and left lateral and bilateral anterolateral, and posterolateral impacts with an acceleration varying from 4.4 to 16.8 m/s(2) while in a car seat with lap-and-shoulder seat belt. RESULTS: For rear-end impacts, whether straight on, right posterolateral, or left posterolateral, all muscles generated 50% or less of the maximal voluntary contraction (MVC) EMG. In straight-on rear impacts, the sternocleidomastoid was symmetrically the most active; however, in posterolateral impacts, the sternocleidomastoid contralateral to impact direction was more active than its counterpart. For a right lateral impact, at the highest acceleration, the left splenius capitis generated 47% of its MVC and the left trapezius did 46% of its MVC. In a left lateral impact, the right splenius capitis generated 48% of its MVC and the right trapezius did 57% of its MVC. In a straight-on frontal impact, the left trapezius generated 35% of its MVC and the right trapezius did 48% of its MVC. In a left anterolateral impact, the right splenius generated 60% of its MVC and the right trapezius did 66% of its MVC. Similarly, in a right anterolateral impact, the contralateral splenius muscle increased its activity to 52% of its MVC and the left trapezius was at 52% of its MVC. CONCLUSIONS: Compared with previously reported impact studies with a rigid seat and 5-point harness, the use of a 3-point lap-and-shoulder seat belt with a standard car seat did not appear to adversely affect cervical muscle response. In very-low-velocity and low-velocity impact experiments, seat belt and seat type may not significantly alter cervical EMG and kinematics.

Musculoskeletal symptoms in support staff in a large telecommunication company.

PRIMARY OBJECTIVE: The primary objective of this study was to determine the extent and severity of the musculoskeletal problems in office workers in a telecommunication company. RESEARCH DESIGN: A questionnaire survey was conducted to assess the prevalence of musculoskeletal disorders' symptoms, their perceived intensity and interaction with ability to work among office workers. METHODS AND PROCEDURES: The Cornell Musculoskeletal Discomfort Questionnaire and Cornell Hand Discomfort Questionnaire developed by the Human Factors and Ergonomics Laboratory at Cornell University were used on a sample of 140 office workers in a telecommunication company. MAIN OUTCOMES AND RESULTS: Discomfort/pain/ache at the wrist level was reported by 86.5% for the left side and 95.5% for the right side. Additionally, discomfort/pain/ache was reported by 77.5% of the sample for neck and 31% of the sample for the left and 50% for the right shoulder region. At the hand site, the area in the distal proximity of the wrist was the most affected site being indicated in 90% of cases for left side and 95% of cases for the right side. CONCLUSIONS: An overview of problems associated with the body parts in office work may allow targeted prevention and intervention.

Cut-points to prevent low back injury due to force exertion at work.

Force exertion is related to low back injuries (LBI). This paper critically reviews the literature concerning cut-points for back force exertion, presents available guidelines in a concise manner, and identifies areas that need further research. The studies reviewed were grouped according to the criteria used to set the cut-point values. Most often cut-points differ than concur. The approach considering physiological, psychophysical, epidemiological, and biomechanical aspects of back force exertion meets the most known criteria and presents the lowest common denominator of instantaneous load for lifting tasks. Further experimental and epidemiological studies in peak load and cumulative exposure are necessary. Compound indices should also be developed for pushing, pulling, and carrying. Future indices should consider electromyographically determined fatigue, differential viscoelastic properties of tissues, aging, and the cross sectional area of back muscles. We hope that this paper contributes to a more systematic appraisal of back force exertion at work.