Min Break Research Articles

Effect of Low-Level Laser Irradiation on Accommodation and Visual Fatigue.

PurposeThis study used low-level laser irradiation on auricular points for the eyes of junior college teenagers with myopia to observe the changes in refractive errors and eye accommodation. According to the Sterner’s study, we used the relationship between the amplitude and subjective symptoms to assess the degree of improvement in visual fatigue caused by changes in accommodation.MethodsParticipants were 49 healthy junior college teenagers, with an average age of 16.04±0.80 years old, and the refractive errors of both eyes were between −1.50 D and −5.00 D. All participants underwent refractive error tests before and after class and after a 30-min break. In a 30-min break, all participants underwent two tests of with (experimental group) and without (control group) low-level laser irradiation on the auricular points. Then, refractive error tests were conducted to evaluate the participants’ eye accommodation.ResultsThe results revealed that with treatment of the auricular points with and without low-level laser irradiation, the refractive error of the participants’ binocular left and right eyes decreased by −0.12 D (−0.18 D) in the experimental grou and by −0.05 D (−0.02D) in the control group. For the amplitudes of accommodation (AA) examination, the AA of the participants’ binocular in the experimental group became 7.98 ± 1.35 D (7.65 ± 1.37 D). The AA of participants’ binocular can recover to the level before the class.ConclusionThe results indicated that low-level laser irradiation at auricular points restored the eye accommodation faster than did natural closing of the eyes.

Thai version of the Survey Instrument for Natural History, Aetiology and Prevalence of Patellofemoral Pain: Cross-cultural validation and test-retest reliability

Background/objective: The Survey Instrument for Natural History, Aetiology and Prevalence of Patellofemoral Pain (SNAPPS) is a self-report questionnaire which is a specifically designed measurement instrument to identify patellofemoral pain. It has reported high sensitivity, specificity and test-retest reliability to discriminate between people with knee pain, with or without patellofemoral pain. SNAPPS hasn't been studied in Thailand; therefore, the aim of this study was to cross-culturally adapt the questionnaire into Thai. MethodThis study was separated into two phases: cross-cultural adaptation and test-retest reliability. The Survey Instrument for Natural History, Aetiology and Prevalence of Patellofemoral Pain was translated into Thai following the guidelines for the cross cultural adaptation of self-report measures including six steps. Thirty four knee pain patients performed the test-retest reliability of the final version of this questionnaire. They were clinically diagnosed with patellofemoral pain by a physical therapist. They were asked to complete the questionnaire twice; with the 1st session and 2nd session having a 30 min break between. The intraclass correlation coefficient (ICC3, 1) method was used to determine test-retest reliability. The correlation of SNAPPS and VAS-U, VAS-W, VAS-S, VAS- J, VAS- R, and VAS- SQ were analyzed by Pearson correlation. ResultsThe thirty-four participants (19 males, 15 females; with ages ranging 19–24 years) with patellofemoral pain were assessed twice with a 30 min break between the two sessions. The total scores of section 2 and 4 of the questionnaire indicated very strong test-retest reliability, ranging from 0.83 to 0.954 and the total score was ICC 0.91. Moreover, the Survey Instrument for Natural History, Aetiology and Prevalence of Patellofemoral Pain had a correlation with intensity of pain during ascending and descending stairs. ConclusionThe Thai version of the Survey Instrument for Natural History, Aetiology and Prevalence of Patellofemoral Pain can be used to assess patellofemoral pain in young Thai patients.

A survey of E-learning methods in nursing and medical education during COVID-19 pandemic in India

BackgroundCOVID-19 pandemic has necessitated mandatory e-learning in medical and nursing education. How far are developing countries like India (with wide socioeconomic and cultural diversity) geared up for this challenge remains unexplored. At this critical juncture, we aim to evaluate if online teaching methods are as feasible, acceptable, and effective as in-class teaching for medical/nursing students. ObjectivesThe questionnaire captured: (1) practicability/feasibility of online classes, (2) health issues from online classes, (3) current methods for e-teaching, and (4) student attitudes and preferences. DesignCross-sectional survey. SettingsPopulation-based study in India. ParticipantsNursing and medical undergraduate students (I-IV year). MethodologyThe online questionnaire was distributed to 200 medical and nursing colleges across India. Categorical variables were analyzed using chi-square tests. Binary logistic regression was done to analyze factors predicting health issues in students. p < 0.05 was considered significant. ResultsOverall, 1541 medical and 684 nursing students completed the survey from 156 cities. The availability of laptop (p < 0.0001), Wi-Fi (p < 0.0001), dedicated room (p < 0.0001), and computer proficiency was more in students of affluent families and those from cities (p < 0.0001). Class duration >4 h/day (p < 0.0001), each class >40 min (p < 0.009) and pre-existing health issues (p < 0.0001) predicted the occurrence headache, eyestrain, anxiety, neck/back pain, and sleep disturbance. Power-point presentation was the most widely (80%) used method of teaching. Only 30% got adequate time to interact with teachers. Only 20.4% felt e-learning can replace conventional teaching. Students preferred: 3–6 classes/day, each class <40 min, 10–20 min break between classes and interactive sessions. ConclusionThere is a need to improve information and communication infrastructure to enhance feasibility of e-learning for nursing/medical students in India. There should be guidelines (number of classes/day, length of each class, break between classes, curriculum, etc) to improve the retention capacity in students and reduce health issues. Continuous feedback from teachers and students will be required to make e-learning effective.

Dependency on sex and stimulus quality of nociceptive behavior in a conscious visceral pain rat model

Visceral pain may be influenced by many factors. The aim of this study was to analyze the impact of sex and quality of intracolonic mechanical stimulus on the behavioral manifestations of visceral pain in a preclinical model.Male and female young adult Wistar rats were sedated, and a 5 cm long latex balloon was inserted into the colon. Sedation was reverted and behavior was recorded. The pressure of the intracolonic balloon was gradually increased using a sphygmomanometer. Visceral sensitivity was measured as abdominal contractions in response to mechanical intracolonic stimulation. Two different types of stimulation were used: tonic and phasic. Phasic stimulation consisted of repeating several times (3x) the same short stimulus (20 s) within a 5 min interval allowing a 1 min break between individual stimuli. For tonic stimulation the stimulus was maintained throughout the whole 5 min interval. Both phasic and tonic stimulation produced a pressure-dependent increase of abdominal contractions. The abdominal response was more intense under phasic than under tonic stimulation, but with differences depending on the sex of the animals: females exhibited more contractions than males and of similar duration at all pressures, whereas duration of contractions pressure-dependently increased in males. The duration of tonically stimulated contractions was lower and not sex- or pressure-dependent. In the rat, responses to colonic distension depend on the quality of the stimulus, which also produces sex-dependent differences that must be taken into account in the development of models of pathology and visceral pain treatments.

Acoustic monitors and direct observations provide similar but distinct perspectives on bird assemblages in a lowland forest of eastern Ecuador.

Bird communities in lowland Neotropical forests exhibit temporal and spatial variation in species composition and abundance at multiple scales. Detecting and explaining such variation requires adequate methods for sampling those bird communities but counting birds in highly diverse lowland forests of the Neotropics can be particularly challenging. Point counts are one of the most frequently used methods for counting birds in tropical forests but inter- and intra-observer variability in detecting and identifying sounds may cause problems. Acoustic monitors (passive acoustic monitors; autonomous recording units) provide an alternative and potentially effective method to sample bird communities by acting, in effect, as “point counts”, recording vocalizations at a given point for a set time. I used acoustic monitors to examine patterns of species richness, spatial distribution, and community composition of birds in a lowland forest in eastern Ecuador, one of the most diverse regions on earth. I deployed monitors at 25 locations, each separated by at least 200 m, on each of two 100-ha plots (Harpia, Puma) at Tiputini Biodiversity Station during January–February, 2013–2017. Monitors were set to record for 10 min followed by a 5-min break, from 0545 h to 0810 h (10 recording periods/morning). Recordings were later reviewed to identify species; no attempt was made to distinguish individuals or to estimate distance. Results were compared with contemporaneous direct observations along transects on the same plots. A total of 214 species were identified from recordings on both plots, combined, with slightly more on Harpia (208) than on Puma (188). Number per year ranged from 142 on Harpia in 2016 to 161 on Puma in 2015. Number per point was ~45 with an overall range of 29–68. Number of species detected in recordings was similar to but somewhat less than the number recorded during direct observations. Number of species recorded increased rapidly from the first period (0545–0555 h) to the third (0615–0625 h) but showed little subsequent change. Most species were recorded at relatively few points; the four most widely distributed species were the same on both plots (Patagioenas plumbea, Xiphorhynchus guttatus, Capito aurita, Ramphastos tucanus), all of which are relatively loud canopy or subcanopy species. Ordinations based on species composition illustrated differences between plots based on both recordings and direct observations; similarly, patterns of species composition differed between methods. Acoustic monitors can be an effective tool for sampling bird communities and may be particularly effective and efficient for sampling loud species with distinctive songs. Nonetheless, results from monitors may provide different perspectives on species composition when compared to direct observations. Which method is preferred likely will depend on the specific objectives of individual studies.

Unexpected role of stress as a possible resilience mechanism upon mild traumatic brain injury (mTBI) in mice

IntroductionMild traumatic brain injury (mTBI) is common and associated with cognitive impairment. Stress and mTBI are known to modulate the neural function. The present study aims at exploring the effect of prior stress exposure on cognitive function following mTBI. MethodsEight weeks old male ICR mice were subjected to either stress induced by forced swimming stress alone, stress followed by an immediate mTBI, or stress followed by 30 min break and then mTBI. We had two control groups: SHAM group - a control group which was not exposed to stress nor to mTBI and control mTBI group - a control group which was exposed only to TBI with no stress. Mice were weighed prior and at 12, 24 h and 1 week following interventions. Motor evaluation was conducted by rotarod. Behavioral changes were evaluated using open field, Y maze, elevated plus maze and staircase tests, at 12 h and 1 week following interventions. Brain levels of NMDAR subunits (R1, R2A, R2B), GABABR1, glucocorticoid and mineralocorticoid receptors (GR, MR) were evaluated using western blot. ResultsStress alone, mTBI alone, and stress followed by immediate mTBI resulted in a significant weight loss compared to control (p < 0.05). Stress 30 min prior to mTBI had a protective effect on weight (p = 0.14 compared to control). The stress and mTBI alone groups showed reduced time at the center of the open field arena 1 week after intervention (p < 0.05 for both). Time in the novel arm of the Y maze was significantly shorter in the mTBI and stress followed by delayed mTBI (p = 0.02). Immediate stress prior to mTBI had normalized times in the novel arm (p = 0.95 compared to control). Combination of stress and mTBI significantly modified NMDAR subunits levels (increased NMDAR1, p < 0.008, decreased NMDAR2A p = 0.02) as well as increased MR levels (p = 0.04). ConclusionExposure to stress prior to mTBI may improve the cognitive consequences of mTBI. These data may point towards a novel, unexpected role of stress as a possible resilience mechanism in the setting of mTBI.

Wearing Occlusive Gloves Increases the Density of Staphylococcus aureus in Patients with Hand Eczema.

Hand eczema is frequently colonized with Staphylococcus aureus. Some patients with hand eczema wear occlusive gloves regularly; however, the effect of this on the density of S. aureus is unexplored. The aim of this study is to examine the effect of occlusive gloves on the density of S. aureus sampled from the hands of patients with hand eczema. In an experimental set-up, patients with moderate-to-severe hand eczema wore an occlusive glove on one hand for 4 h with a 30-min break. Bacterial swabs were collected from the most severe eczema lesion on the hand before and immediately after glove exposure. S. aureus colony-forming units were counted and log-transformations used for comparison of before- and after-values. Among 30 patients, 19 (63%) were colonized with S. aureus. After glove occlusion S. aureus colony-forming units increased by a factor of 1.72 (p < 0.01). In conclusion, the density of sampled S. aureus on eczematous skin after prolonged wearing of occlusive gloves is greatly increased.

A Blockchain-Based Voting System for E-Elections in Totalitarian States

The purpose of the present research was to introduce a blockchain-based voting system so that any state, including totalitarian states, can show interest in using it. In this method, a hybrid voting system with two centralized and distributed systems was used. Its centralized system is one of the most common voter identification and polling models, and its distributed system, which is designed with Ethereum public blockchain, is voting for voters. Totalitarian states are not interested in announcing the results online. Also, the lack of trust in E-voting systems by both states and voters has led to E-voting in important political elections in most states as support for manual or paper voting. Based on the results of field research with this voting system, it was possible to create a 7 min break between the end of the voting process and the announcement of the results for political considerations. This break can be increased by agreement. The results of the votes cannot be manipulated in any way. Survey results should also be communicated to voters before the voting process. This voting system can improve the level of democracy and maximum participation. It is hoped that the spread of distributed technologies, especially the blockchain, will pave the way for the spread of justice and democracy around the world.

Assessment of Dermatology Residents During the Covid-19 Pandemic: A Single Institute Experience.

To meet the challenges of Covid-19, educators had to make sudden revisions to the educational curriculum and examination methods.[1] Universities worldwide have adopted online teaching methods through video conferencing platforms like google meet and zoom, which provide basic plans free of charge.[23] Quarterly resident assessment via spotter examination and viva is an integral part of our department's training program to evaluate residents, and aid in their learning. Our conventional spotter examination includes rallying approximately 40 patients with diverse dermatological diseases to our out-patient department. After a meticulous screening, about 20–30 cases are selected for the examination and residents are assessed based on five cases by two examiners individually. Our conventional viva exam involves residents shuffling between five stations. Each station includes one or two dermatology topics, and is led by one examiner. Considering the significant reduction in the patient load in our out-patient and in-patient services, and strict adherence to the norm of social distancing, we planned a virtual assessment for the residents. For the spotter assessment, we divided the residents and examiners into five groups. Each group had two examiners, 4–5 residents, and two senior residents for coordinating the exam. Each resident was shown photographs of eight clinical cases in google meet using PowerPoint. In addition, the final-year residents were asked to work up live cases admitted in our in-patient ward and were evaluated virtually through google meet by presenting clinical images of the same cases. The viva lasted for approximately 30 min per short case and 5 min per spotter. Each examiner evaluated 4-5 residents with four cases, and two examiners assessed each resident. The viva exam, which involved interviewing residents on various dermatology topics, was also conducted virtually using google meet [Figure 1]. The residents and examiners were divided into two equal groups with eleven stations each. Five of the eleven stations were “viva stations,” and the remaining were “waiting stations.” Each viva station was headed by one examiner. The distribution of the topics into these five viva stations is outlined in Figure 1. At the beginning of the viva, we assigned each resident to one station using separate google meet links. Residents moved to the next station every 15 min. In case a viva exceeded 15 min, their waiting period at the next station decreased. Unless the viva exceeded 30 min, this arrangement was fail-safe. Each examiner interviewed eleven residents, and each resident faced five examiners.Figure 1: Schematic representation of the viva examination planWe sent online feedback forms using https://docs.google.com/forms/u/0/to all residents and examiners after the spotter and viva examinations and recorded their responses anonymously [Table 1]. According to the residents and examiners, the virtual spotter exam was well organized and time efficient. Residents faced technical snags in internet Wi-Fi services, audio-visual output, and lag in loading images. At the same time, examiners complained of poor audio connection and background noise while interviewing some residents. Residents suggested allotting a predesignated time to analyze the images and providing multiple views of a lesion. They also sought context to the images like necessary demographic details. They acknowledged the variety of cases, from classical to rare disorders but proposed that the difficulty level be uniform across the training level and groups. They felt that the virtual exam was less stressful than the in-person exam, as they did not have to face the examiners directly and could give the exam from a comfortable place. Examiners observed that the virtual exam was convenient as it avoided the exam day hassle of screening many patients and sending back the unselected cases. Also, it avoided the inconvenience caused to patients in terms of traveling and waiting for long hours. The examiners wanted to allocate more than 5 min per spotter and interview more residents with fewer cases each.Table 1: Feedback questions and responses from residents and examiners for the spotter and viva examinationsRegarding the viva exam, examiners and residents appreciated the smooth transfer of residents from one station to the next. It was well-timed, efficient, safe, and avoided the arduous task of shuffling residents from one examination room to another. Examiners needed more time to interview final-year residents and a scheduled 15-min break in between. Our experience shows the benefits and limitations of virtual exam methods. Residents' acceptance, a key component in the new program, was high. The virtual “picture-based” exam may enhance residents' ability to cope with teledermatology and vice versa. It supports shifting the emphasis placed on description and diagnosis to management and patient counselling. It serves as an adequate stop-gap measure till the Covid-19 situation improves or maybe even after the pandemic, at least partially, owing to its advantages. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

A Systematic Evaluation of Six Different Physical Activity Routines: A Strategic Science Approach

ABSTRACT Physical inactivity and sedentary behaviors are major contributors to chronic diseases and premature mortality. Although the benefits of physical activity have been documented, no study has systematically evaluated the feasibility and satisfaction of different physical activity routines designed for workplace settings. Therefore, the objectives of this research were to develop and evaluate six different types of 15-min physical activity routines. Based on pilot testing, we developed six different physical activity routines designed for the 15-min break during the workday, and 12 dimensions were used to evaluate each routine. The dimensions were as follows: appropriateness of work attire, benefit, challenge, complexity, confidence, effort (i.e., physical), embarrassment, enjoyment, fatigue, flexibility, likability, and sweat (i.e., perspiration). Before completing the ratings, participants received definitions of each dimension. Ninety-four full-time employees participated in six routines (i.e., aerobic dance, ballet, Booster Break, circuit training, muscle strengthening, and yoga) and rated their experiences using a 5-point Likert scale immediately after each session. All routines received some favorable ratings and seemed acceptable as a workplace activity. Circuit training and aerobic dance ranked highest on challenge, complexity, effort (i.e., physical), embarrassment, fatigue, and sweat, and low on work attire appropriateness. Booster Break ranked relatively high on benefit, confidence, likability, and work attire appropriateness; moderate on fatigue; and low on sweat and embarrassment. Circuit training and aerobic dance routines were the most challenging and appropriate for workforces with employees who are physically active and/or prefer challenges. For workforces with a diversity of preferences, abilities, or new to physical activity routines, the Booster Break is recommended because it was rated favorably on all dimensions. Future research is recommended to replicate these findings and improve the implementation effectiveness of work break routines.

No Evidence That Hyperpnea-Based Respiratory Muscle Training Affects Indexes of Cardiovascular Health in Young Healthy Adults.

IntroductionThe chronic effects of respiratory muscle training (RMT) on the cardiovascular system remain unclear. This investigation tested to which degree a single sessions of RMT with or without added vibration, which could enhance peripheral blood flow and vascular response, or a 4-week RMT program could result in changes in pulse wave velocity (PWV), blood pressure (systolic, SBP; diastolic, DBP) and other markers of cardiovascular health.MethodsSixteen young and healthy participants (8 m/8f) performed 15 min of either continuous normocapnic hyperpnea (RMET), sprint-interval-type hyperpnea (RMSIT) or a control session (quiet sitting). Sessions were performed once with and once without passive vibration of the lower limbs. To assess training-induced adaptations, thirty-four young and healthy participants (17 m/17f) were measured before and after 4 weeks (three weekly sessions) of RMET (n = 13, 30-min sessions of normocapnic hyperpnea), RMSIT [n = 11, 6 × 1 min (1 min break) normocapnic hyperpnea with added resistance] or placebo (n = 10).ResultsSBP was elevated from baseline at 5 min after each RMT session, but returned to baseline levels after 15 min, whereas DBP was unchanged from baseline following RMT. Carotid-femoral PWV (PWVCF) was elevated at 5 and 15 min after RMT compared to baseline (main effect of time, P = 0.001), whereas no changes were seen for carotid-radial PWV (PWVCR) or the PWVCF/PWVCR ratio. Vibration had no effects in any of the interventions. Following the 4-week training period, no differences from the placebo group were seen for SBP (P = 0.686), DBP (P = 0.233), PWVCF (P = 0.844), PWVCR (P = 0.815) or the PWVCF/PWVCR ratio (P = 0.389).Discussion/ConclusionAlthough 15 min of RMT sessions elicited transient increases in PWVCF and SBP, no changes were detected following 4 weeks of either RMET or RMSIT. Adding passive vibration of the lower limbs during RMT sessions did not provide additional value to the session with regards to vascular responses.

Altered muscle activation in agility dogs performing warm-up exercises: an acoustic myography study

Agility is physically demanding and dogs encounter a considerable risk of injury during training and competition. Pre-performance warm-up is used routinely among human athletes to prepare the tissues for these physical demands, but in canine sports evidence for effects of warm-up is lacking. The aim of this study was to investigate the effects of warm-up in dogs on two major muscles involved in locomotion. It was hypothesised that, after warm-up, the muscles would be used more efficiently (more fibre resting time/total time), recruit fewer fibres (reduced spatial summation) and/or activated with a lower firing frequency (reduced temporal summation). The following factors ‘sex, age, weight, height, training level and agility experience’ were evaluated for their potential impact on muscle function parameters. Fourteen large (≥46 cm at the withers) agility dogs of different breeds and training levels performed a 5 min warm-up program three times, with a 2 min break between the programs for recording purposes. Acoustic myography sensors were attached on the skin over the muscles m. triceps brachii (TB) and m. gluteus superficialis (GS). Recordings of muscle activity were made, while the dogs trotted before warm-up and after each 5 min warm-up program. The dogs used TB more efficiently after 5 min (P&lt;0.05), 10 min (P&lt;0.05) and 15 min (P&lt;0.001) of exercise compared to pre-warm-up values. No changes were found in the activity of GS. For well-trained dogs, TB recruited fewer muscle fibres after 10 and 15 min of warm-up compared to dogs that trained less than 1 h weekly (P&lt;0.03). For dogs with more than 2 years of experience, GS had a lower firing frequency before and after 10 min warm-up compared to dogs with less experience. The results indicate that warm-up alters muscle activation by an increased muscular efficiency. Training level and experience have an influence on muscle function parameters.

Quantitative accuracy remains after shortening of dynamic [18F]flortaucipir PET protocol

AbstractBackgroundTau pathology can be assessed by [18F]flortaucipir positron emission tomography (PET). Dynamic PET protocols allow for accurate quantification of [18F]flortaucipir specific binding. However, dynamic acquisitions can be challenging or burdensome to patients given the long required scan duration of 130 min, especially in persons with cognitive impairment due to Alzheimer’s disease (AD). Therefore, the current study assessed the effect of shorter scan protocols for [18F]flortaucipir PET on its quantitative accuracy.MethodFor this study, two study samples were used: 10 Alzheimer disease (AD) patients and 10 healthy controls (HC) with arterial blood sampling, and 8 AD patients and 6 HCs with a test‐retest scan protocol but without arterial sampling. All subjects underwent a 130‐minute dynamic [18F]flortaucipir PET scan with a 20 min break after 60 minutes. First, the second part of the scan was shortened to 80‐120, 80‐110 and 80‐100 minutes p.i.. Second, the first part of the scan was shortened to 0‐50, 0‐40, and 0‐30 min p.i.. To fill the gap of missing time frames in the reference region (i.e. grey matter cerebellum) time activity curves, four different interpolation methods were tested: 2T4k_VB model using population‐based input‐function (2T4k_POP‐IP), cubic, linear and exponential interpolations. Regional BPND values estimated using SRTM and/or RPM and different scan protocols were compared to the respective values estimated using the original scan acquisition. In addition, test‐retest repeatability (TRT) of the RPM BPND values estimated using the optimal shortest scan duration was assessed.ResultRPM BPND values obtained using a shortened second part of the PET scan had negligible effect on the accuracy of parameter estimates (Table 1). The RPM BPND values using 0‐30/80‐100 min with 2T4k_POP‐IP interpolation had the best correlation with original DVR‐1, SRTM and RPM BPND (r2=0.95, slope=0.91; r2=0.97, slope=0.88; r2=0.99, slope=0.96). The TRT remained similar using the shortest scan duration (Figure 1).ConclusionThe current study demonstrated that accurate [18F]flortaucipir quantification can be obtained using a scan protocol of 0‐30/80‐100 min p.i.. With this reduction in total scan duration the scan will be less burdensome while remaining quantitatively accurate.

The Effect of CO2 Concentration on Children’s Well-Being during the Process of Learning

There are more than 200 thousand pupils in Latvia. Most of them are still learning in non-renovated classrooms without proper mechanical ventilation. The classrooms are often ventilated only during the breaks by opening windows. This can lead to increased CO2 levels and reduced mental performance. To test how CO2 concentration in classrooms influences student attention level and their ability to perform mental tasks, the students had to complete a short test at the start and the end of the class. At the same time CO2 concentration, temperature and relative humidity were logged. In addition, an anonymous survey on how the pupils felt regarding the overall indoor environmental quality (IEQ) in the classroom, their thermal sensation, are they fatigued, any difficulty concentrating and if they have headaches during the lesson performed. The measurements were performed in a Secondary School in Daugavpils, Latvia. The analysis of results shows that existing 10 min breaks are not enough to fully ventilate the classroom, and they must be increased to at least 15 min. At the same time, 30 min breaks can be reduced to 20 min. The correlation between CO2 concentration and test results of pupils’ performance test results is noticeable but not definitive. It indicates that at increased CO2 levels the performance lowers—when the concentration of CO2 corresponds only to the Category 3 norm, the lowest results are achieved while the best results are when the CO2 concentration level corresponds to Category 1. To improve the study, observations of CO2 concentrations must be extended throughout the school year, as well as measurements in other classrooms in the school should be made.

Cardiorespiratory and Neuromuscular Demand of Daily Centrifugation: Results From the 60-Day AGBRESA Bed Rest Study

PurposeLong stays in space require countermeasures for the degrading effects of weightlessness on the human body, and artificial gravity (AG) has been proposed as an integrated countermeasure. The aim of this study was to assess the cardiorespiratory and neuromuscular demand of AG elicited via daily centrifugation during 60 days of bed rest.MethodsTwenty four participants (33 ± 9 y, 175 ± 9 cm, 74 ± 10 kg, 8 female) were subjected to 60 days of strict six-degree head-down tilt (HDT) bed rest and were randomly allocated to one of three experimental groups: 30 min of daily centrifugation with an acceleration of 1 g at the center of mass and 2 g at the feet applied continuously (cAG) or intermittently in 6 epochs of 5 min each, separated by 3 min breaks (iAG), or non-centrifuged control (CTRL). Cardiorespiratory demand during centrifugation was assessed at the beginning (HDT3) and end (HDT60) of the bed rest phase via spirometry and heart rate monitoring, leg muscle activation was monitored via electromyography.ResultsOn average, analyses of variance revealed that heart rate during centrifugation increased by 40% (iAG) and 60% (cAG) compared to resting values (p < 0.001), while oxygen uptake did not change significantly (p = 0.96). There was a preference for calf over knee extensor muscle activation (active time soleus 57 ± 27%, gastrocnemius medialis 45 ± 27% and vastus lateralis 27 ± 27%, p < 0.001), with large inter-individual differences in leg muscle active time. AG could not prevent the increase in resting heart rate after bed rest. For most of the recorded parameters, there were little differences between cAG and iAG, with the increase in heart rate during centrifugation being a notable exception (greater increase for cAG, p = 0.01).ConclusionDaily 30 min bouts of artificial gravity elicited by centrifugation put a substantial demand on the heart as a pump without increasing oxygen consumption. If centrifugation is to be used as a countermeasure for the deteriorating effects of microgravity on physical performance, we recommend combining it with strenuous exercise.

Exercise intensity during walking football for men and women aged 60+ in comparison to traditional small-sided football – a pilot study

ABSTRACT Purpose: The aim of the present study was to quantify the intensity, perceived exertion and enjoyment of participation in walking football (WF) for elderly men and women compared to traditional small-sided running football (RF) and walking (W). Methods: 32 men and women aged 60–83 from recreational football teams performed a 5-min W, followed by 10-min WF and RF games in a counterbalanced order, separated by an 8–10 min break. The men and women played 5v5 and 6v6, respectively, on small-sided football pitches (men: 40 × 16.5 m; women 40 × 30 m) with medium-sized goals (3 × 1.5 m). Heart rate (HR) and locomotor activities were monitored throughout sessions and rating of perceived exertion (RPE) and Physical Activity Enjoyment Scale (PACES) scores were determined immediately after sessions. Results: During RF, mean HR was higher (P 0.05) compared to WF and W for both men aged 60+ (126 ± 23 vs 112 ± 19 and 98 ± 19 beats/min) and women aged 60+ (144 ± 24 vs 133 ± 30 and 112 ± 20 beats/min), and higher (P < 0.05) during WF than W. During RF, more distance (P < 0.05) was covered at >8 km/h compared to WF and W for both men aged 60+ (134 ± 73 vs 36 ± 27 and 6 ± 7 m) and women aged 60+ (119 ± 89 vs 39 ± 38 and 1 ± 1 m), with more distance (p < 0.05) during WF compared to W. Both men and women had higher PACES and RPE scores (P < 0.05) for RF compared to WF. Conclusion: WF for elderly men and women results in higher heart rates and more distance covered in more intense speed zones than W, but less than in traditional small-sided football. Future studies should elucidate the hypothesis that WF is more effective in relation to fitness and health benefits compared to W, but less effective compared to small-sided traditional football.

Feasibility of training community health workers to conduct periodontal examinations: a validation study in rural Nepal

BackgroundIn many low- and middle-income countries, insufficient human resources limit access to oral health services. Shifting clinical tasks to less specialized health professionals, such as community health workers, has been used as a strategy to expand the health workforce, especially in remote or underserved locations. The objective of this study was to evaluate the validity of periodontal examinations conducted by auxiliary nurse midwives in a rural home setting in Nepal.MethodsTwenty-one pregnant women < 26 weeks gestation from Sarlahi District, Nepal, underwent full mouth periodontal examinations measuring probing depth (PD) and bleeding on probing (BOP) on 6 sites per tooth by one of five auxiliary nurse midwives, who were trained for this study but had no previous training in dentistry. After a 15-min break, each participant was examined again by an experienced dentist. Measures of validity for PD and BOP were calculated comparing the pooled and individual auxiliary nurse midwives to the dentist. A multivariable GEE model estimated the effect of periodontal characteristics on agreement between the auxiliary nurse midwives and the dentist.ResultsParticipant mean age was 22 years (SD: ±3 years), mean PD was 1.4 mm (SD: 03 mm), and 86% of women had BOP (according to the dentist). Percent agreement, weighted kappa scores, and intraclass correlation coefficients for PD, with an allowance of ±1 mm, exceeded 99%, 0.7, and 0.9, respectively, indicating an acceptable level of agreement. Auxiliary nurse midwives tended to report higher PD scores relative to the dentist, although this over-estimation was small and unlikely to impact population-based estimates of important indicators of oral health status. GEE regression modeling indicated similar agreement for mandible vs. maxilla, left vs. right side, and PD (≤2 mm, > 2 mm), and lower agreement for posterior teeth and lingual and proximal sites.ConclusionAuxiliary nurse midwives were able to accurately conduct periodontal examinations in a rural home setting, suggesting the potential to shift tasks away from highly trained dentists and periodontal examiners in low-resource communities.Trial registrationClinicalTrials.gov Identifier: NCT01177111 (Nepal Oil Massage Study); registered on August 6th, 2010.

Evaluation of Anaerobic Digestion of Dairy Wastewater in an Innovative Multi-Section Horizontal Flow Reactor

The aim of this study was the performance evaluation of anaerobic digestion of dairy wastewater in a multi-section horizontal flow reactor (HFAR) equipped with microwave and ultrasonic generators to stimulate biochemical processes. The effects of increasing organic loading rate (OLR) ranging from 1.0 g chemical oxygen demand (COD)/L·d to 4.0 g COD/L·d on treatment performance, biogas production, and percentage of methane yield were determined. The highest organic compounds removals (about 85% as COD and total organic carbon—TOC) were obtained at OLR of 1.0–2.0 g COD/L·d. The highest biogas yield of 0.33 ± 0.03 L/g COD removed and methane content in biogas of 68.1 ± 5.8% were recorded at OLR of 1.0 g COD/L·d, while at OLR of 2.0 g COD/L·d it was 0.31 ± 0.02 L/COD removed and 66.3 ± 5.7%, respectively. Increasing of the OLR led to a reduction in biogas productivity as well as a decrease in methane content in biogas. The best technological effects were recorded in series with an operating mode of ultrasonic generators of 2 min work/28 min break. More intensive sonication reduced the efficiency of anaerobic digestion of dairy wastewater as well as biogas production. A low nutrient removal efficiency was observed in all tested series of the experiment, which ranged from 2.04 ± 0.38 to 4.59 ± 0.68% for phosphorus and from 9.67 ± 3.36 to 20.36 ± 0.32% for nitrogen. The effects obtained in the study (referring to the efficiency of wastewater treatment, biogas production, as well as to the results of economic analysis) proved that the HFAR can be competitive to existing industrial technologies for food wastewater treatment.

Warm periods in repeated cold stresses protect Drosophila against ionoregulatory collapse, chilling injury, and reproductive deficits

In some insects, repeated cold stresses, characterized by warm periods that interrupt a sustained cold period, have been found to yield survival benefits over continuous cold stresses, but at the cost of reproduction. During a cold stress, chill susceptible insects like Drosophila melanogaster suffer from a loss of ion and water balance, and the current model of recovery from chilling posits that re-establishment of ion homeostasis begins upon return to a warm environment, but that it takes minutes to hours for an insect to fully restore homeostasis. Following this ionoregulatory model of chill coma recovery, we predicted that the longer the duration of the warm periods between cold stresses, the better a fly will endure a subsequent chill coma event and the more likely they will be to survive. We also predicted, however, that this recovery may lead to reduced fecundity, possibly due to allocation of energy reserves away from reproduction. Here, female D.melanogaster were treated to a long continuous cold stress (25 h at 0 °C), or experienced the same total time in the cold with repeated short (15 min), or long (120 min) breaks at 22 °C. We found that warm periods in general improved survival outcomes, and individuals that recovered for more time in between cold periods had significantly lower rates of injury, faster recovery from chill coma, and produced greater, rather than fewer, offspring. These improvements in chill tolerance were associated with mitigation of ionoregulatory collapse, as flies that experienced either short or long warm periods better maintained low hemolymph [K+]. Thus, warm periods that interrupt cold periods improve cold tolerance and fertility in D. melanogaster females relative to a single sustained cold stress, potentially because this time allows for recovery of ion and water homeostasis.

Magnetic resonance elastography of the supraspinatus muscle: A preliminary study on test-retest repeatability and wave quality with different frequencies and image filtering

The purpose of this study was to determine an optimal condition (vibration frequency and image filtering) for stiffness estimation with high accuracy and stiffness measurement with high repeatability in magnetic resonance elastography (MRE) of the supraspinatus muscle. Nine healthy volunteers underwent two MRE exams separated by at least a 30 min break, on the same day. MRE acquisitions were performed with a gradient-echo type multi-echo MR sequence at 75, 100, and 125 Hz pneumatic vibration. Wave images were processed by a bandpass filter or filter combining bandpass and directional filters (bandpass-directional filter). An observer specified the region of interest (ROI) on clear wave propagation in the supraspinatus muscle, within which the observer measured the stiffness. This study assessed wave image quality according to two indices, as a substitute for the assessment of the accuracy of the stiffness estimation. One is the size of the clear wave propagation area (ROI size used to measure the stiffness) and the other is the qualitative stiffness resolution score in that area. These measurements made by the observer were repeated twice at least one month apart after each MRE exam.This study assessed the intra-examiner and observer repeatability of the stiffness value, ROI size and resolution score in each combination of vibration frequency and image filter. Repeatability of the data was analyzed using the intraclass correlation coefficient (ICC) and 95% limits-of-agreement (LOA) in Bland-Altman analysis. The analyses on intra-examiner and observer repeatability of stiffness indicated that the ICC and 95% LOA were not varied greatly depending on vibration frequency and image filter (intra-examiner repeatability, ICC range, 0.79 to 0.88; 95% LOA range, ±23.95 to ±32.42%, intra-observer repeatability, ICC range, 0.98 to 1.00; 95% LOA range, ±5.10 to ±10.99%). In the analyses on intra-examiner repeatability of ROI size, ICCs were rather low (ranging from: 0.03 to 0.69) while 95% LOA was large in all the combinations of vibration frequency and image filter (ranging from: ±62.66 to ±83.33%). In the analyses on intra-observer repeatability of ROI size, ICCs were sufficiently high in the total combination of vibration frequency and image filter (ranging from 0.80 to 0.87) while the 95% LOAs were better (lower) in the bandpass-directional filter than the bandpass filter (bandpass directional filter vs. bandpass filter, ±28.81 vs. ±54.83% at 75 Hz; ±25.63 vs. ±37.83% at 100 Hz; ±34.51 vs. ±43.36% at 125 Hz). In the analyses on intra-examiner and observer repeatability of resolution score, the mean difference (bias) between the two exams (or observations) was significantly low and there was almost no difference across all the combinations of vibration frequency and image filter (range of bias: −0.11–0.11 and −0.17–0.00, respectively).Additionally, effects of vibration frequency and image filter on wave image quality (ROI size and resolution score) were assessed separately in each exam. Both mean ROI size and resolution score in the bandpass-directional filter were larger than those in the bandpass filter. Among the data in the bandpass-directional filter, mean ROI size was larger at 75 and 100 Hz, and mean resolution score was larger at 100 and 125 Hz. Taking into consideration with the results of repeatability and wave image quality, the present results suggest that optimal vibration frequency and image filter for MRE of the supraspinatus muscles is 100 Hz and bandpass-directional filter, respectively.