Gender dependent EMGs of runners resolved by time/frequency and principal pattern analysis.

A promising approach for the analysis of surface electromyograms is to use wavelets to determine the spectral distribution of the signal intensity at any time. The authors have recently proposed using non-linearly scaled wavelets to obtain intensity patterns, which reflect the spectral distribution at any given time point. Further analysis of intensity-patterns is greatly facilitated by representing them as linear combinations of a base set of principal-patterns. The weight with which each principal-pattern contributes to the intensity-pattern can be represented on a set of orthogonal axes that span a previously introduced pattern space. The purpose of the present study was to show how to use pattern space to discriminate and classify male and female runners based on the electromyograms of five muscles of the limb. The results showed that there were significant gender specific differences, which allowed more than a 95% correct classification of the subjects as males or females. Classification was possible irrespective of the shod condition while running. Gender specific differences occurred at well-defined time periods during the movement. Common to both genders was that spectral changes did not parallel the changes in total signal intensity.     

Study of function of fingers by physiological tremor

1. 1. Physiological tremor is invisible mechanical vibration of body parts.

2. 2. It has two peak frequencies in the p ower spectrum. The origin of the peaks has not been well elucidated. Therefore, the mechanism and its application to labor science is studied in the paper.

3. 3. The effect of immersion of fingers in water and of loading weights on fingers are performed to elucidate the mechanism involved.

4. 4. It is found that the power spectrum output has two bands from the lower frequency band (1.5–18 Hz) from the CNS and the higher frequency band (18–50 Hz).

5. 5. These results are applied to the evaluation of fatigue of fingers in tapping and typing work.

6. 6. The total power, which is the sum of power spectrum in frequency range between 1.5 and 50 Hz, is employed as evaluational index. The change of total power explains finger fatigue during tapping and typing loads.

7. 7. Physiological tremor is an effective way of evaluating the function of fingers in human work.

Investigations on the surveys of office environments and the total evaluation method—IAQ-Index

1. 1. A comprehensive study was made to establish evaluation methods for better office environments.

2. 2. In our study, measurements of thermal, acoustic, lighting, airflow and air quality conditions in indoor environments were made as well as questionnaire to the occupants on the evaluations of indoor environments and the feeling of fatigue.

3. 3. We also made an attempt to rate the evaluation value based on concepts and standards to evaluate totally office environments in a view point of “the office environments where people can work healthy and vigorously”. The evaluation values were called IAQ-index.

Research on office environment evaluation and worker fatigue

1. 1. The purpose of this research was to study the relationship between indoor environment and fatigue by analyzing office workers' fatigue and evaluation of indoor environment according to occupation.

2. 2. This study concerned office workers' fatigue (before and after work), questionnaires on indoor environment, and measurement of the physical environment. The subject (562 people) were businessmen, interior designers, and salesmen.

3. 3. The result of this study showed that there was a high correlation between the office workers' feeling of fatigue and the office environment.

4. 4. This research demonstrated that the workers of each type of occupation responde differently to similar office environments.

Plasticity of response to equal quantities of endurance training separated by non-training in humans

1. 1. The pattern of elevation of several serum biochemical indices (BI) of training stress (creatine kinase, CK; lactate dehydrogenase, LDH; aspartate aminotransferase, AST, Ca²⁺; urate, UR; urea, U; total protein, Prot; cholesterol, C) were measured serially through two extended periods of training, including taper (50 days each) separated by a period of complete non-training (90 days) in two male subjects.

2. 2. The patterns of variation in BI were compared with similar variation in elements of a two compartment model predicting performance from training.

3. 3. These elements arbitrarily described as Fitness [g(t)] and Fatigue [h(t)] were estimated daily from a daily training impulse [w(t)] defined from the duration time and heart rate elevation of an individual in a training session.

4. 4. g(t) and h(t) were used to predict performance [p(t)] which might be expected from the training undertaken. So that: p(t) = k₁g(t) — k₂h(t) where k₁ and k₂ are arbitrary constants.

5. 5. Performance p(t) when iteratively modelled against a Criterion running Performance, Cp(t) measured serially throughout training, over a standard distance, then defines the pattern of variation in the elements g(t) and h(t) (Morton et al., 1990).

6. 6. Hard training for 28 days and a succeeding 22 days of taper in each training period produced a rise and fall in elevated serum enzyme activity, ESEA, (CK, LDH and AST) which mirrored the time-course pattern of h(t), the fatigue element of the dose/response model of training, with a slight phase delay.

7. 7. Thus ESEA was already declining during hard training.

8. 8. During the taper period ESEA declined rapidly to base line. This response was remarkably symmetrical in each, separate training period.

9. 9. The Criterion running performance (CP) declined during hard training and rebounded throughout the taper period reaching an asymptote before beginning to decline again as training fitness [g(t)] was lost, although the fatigue [h(t)] state was now minimal.

10. 10. Serum Prot, U, Ur respectively were also elevated throughout hard training, first following the hypothesized h(t) curve but showing a biphasic response, declining during the latter phase of hard training, and rising again during taper.

11. 11. The symmetry of response of these indices in each period was less evident than the ESEA response. None of the BI patterns measured was in phase with g(t), all, seemingly, reflected the catabolic rather than the anabolic process of hard training.

Accumulation of bicarbonate in intact chloroplasts following a pH gradient

With silicone layer filtering centrifugation the uptake of radioactively labelled bicarbonate into isolated spinach chloroplasts was followed. This uptake was shown to have the following properties:

1. (a) It is so rapid that the kinetics of uptake usually cannot be resolved.

2. (b) Bicarbonate is accumulated in the stroma. The factor between the internal and external concentrations increases greatly when the pH of the medium is lowered from pH 8.5 to pH 7.0.

3. (c) The accumulation factor is independent of the concentration in the medium for a long concentration range.

4. (d) The accumulation of bicarbonate is increased when the chloroplasts are illuminated. This increase is abolished by the addition of uncoupler.

5. (e) Diamox, an inhibitor of carbonic anhydrase, inhibits the rate of bicarbonate uptake.

The activity of carbonic anhydrase was assayed in isolated chloroplasts and in leaf homogenates. In agreement with earlier reports the main activity was found to be located in the chloroplasts. This activity is latent; it can be only assayed if the chloroplasts are osmotically shocked.

From these results the following conclusions have been drawn:

1. (a) The inner membrane is impermeable to protons. Light-driven proton transport into the thylakoid space causes an alkalisation of the stroma.

2. (b) The uptake of bicarbonate proceeds via diffusion of CO₂ across the inner membrane. There are no indications for a specific transport of bicarbonate.

3. (c) The CO₂ concentration in the chloroplasts may be equal to the CO₂ concentration in the external space. The distribution of bicarbonate between the two compartments is inversely proportional to the distribution of protons.

A possible involvement of carbonic anhydrase and the bicarbonate pool in the stroma in increasing the CO₂ affinity of CO₂ fixation is discussed.     

Relationships between forced vital capacity and subjective responses to added resistive load to inspiration

1. 1. This study was conducted to investigate the effects of forced vital capacity on breathing pattern and subjective responses to inspiratory resistance.

2. 2. The subjects were divided into two groups according to their %FVC [large (L) and small (S) group; five subjects in each].

3. 3. Added inspiratory resistances were 0.6 (control), 1.5 (R1), 2.5 (R2), 3.1 (R3) cmH₂O · 1⁻¹ · s.

4. 4. Breathing pattern was analyzed by personal computer during rest and exercise with bicycle ergometer.

5. 5. The degree of sensation of breathing difficulty was expressed in SNS reported in our previous study.

6. 6. SNS in S group increased with resistance while no tendency was observed in L group. SNS in S group was significantly greater than that in L group at R3 condition.

7. 7. The breathing pattern of S group was characterized in smaller tidal volume and faster respiratory frequency compared to those of L group with no resistive load.

8. 8. However, outstanding changes in breathing pattern were observed in S group with longer inspiratory time and lower mean inspiratory flow rate when resistive loads were added, which led to increased tidal volume and decreased respiratory frequency.

Thermosensitivity during embryonic development of Lymnaea stagnalis (Mollusca)

1. 1.|The percentage of survival after 1 hr at 40.0°C is lowest at the larval trochophore stage and at hatching of the young snail.

2. 2.|Heat resistance depends on the stage of development.

3. 3.|From the early cleavage stage onwards a higher percentage of embryos can withstand high temperature after a previous heat treatment than without it.

4. 4.|The pattern of thermosensitivity is discussed in relation to the organizational level of the stage of development.

5. 5.|It is concluded that the developing Lymnaea is a suitable system to study heat resistance and thermotolerance at the level of cells, organs and organism.

Validation of a Noninvasive Method to Measure Brain Temperature In Vivo Using 1H NMR Spectroscopy

Abstract: The goal of this study was to evaluate the potential of using the difference between the ¹H NMR frequencies of water and N -acetylaspartic acid (NAA) to measure brain temperature noninvasively. All water-suppressed and non-water-suppressed ¹H NMR spectra were obtained at a field strength of 4.7 T using a surface coil. Experiments performed on model solutions revealed a decrease in the difference between NMR frequencies for NAA and water as a linear function of increasing temperature from 14 to 45°C. Changing pH in the range 5.5–7.6 produced no discernible trends for concurrent changes in the slope and intercept of the linear relationship. There were minor changes in slope and intercept for solutions containing 80 or 100 mg of protein/ml versus no protein, but these changes were not considered to be of sufficient magnitude to deter the use of this approach to measure brain temperature. The protein content of swine cerebral cortex was found to remain constant from newborn to 1 month old (78 ± 12 mg/g; n = 41). Therefore, data collected for the model solution containing 80 mg of protein/ml were used as a calibration curve to calculate brain temperature in eight swine during control, hypothermia, ischemia, postischemia, or death, over a temperature range of 23–40°C. A plot of 61 temperatures determined from ¹H NMR versus temperatures measured from an optical fiber probe sensor implanted 1 cm into the cerebral cortex showed excellent linear agreement (slope = 1.00 ± 0.03, r ² = 0.96). We conclude that ¹H NMR spectroscopy presents a practical means of making noninvasive measurements of brain temperature with an accuracy of better than ± 1°C.     

Comparison of thermal responses with and without cold protective clothing in a warm environment after severe cold exposures

1. 1. Ten male students remained in a severely cold room (-25°C) for 20 min. thereafter, they transferred in a warm room (25°C) for 20 min.

2. 2. This pattern was repeated three times, total cold exposure time amounting to 60 min.

3. 3. In the warm room, the subjects removed their cold-protective jackets, or wore them continously.

4. 4. Rectal temperature, skin temperatures, manual performance and thermal comfort were measured during the experiment.

5. 5. Removing cold-protective jackets after severe cold exposure increased peripheral skin temperatures and reduced the discomfort in the warm room.

6. 6. However, these results were accompanied by a greater decrease in rectal temperature and manual performance.

7. 7. It is recommended that workers continue to wear cold-protective clothing in the warm areas outside of the cold storage to prevent decreases in deep body temperature and work efficiency caused by repated cold exposures.

Development of autonomic and behavioural thermoregulation in turkeys (Meleagris gallopavo)

1. 1.|Heat production (HP) and body temperature (T_b) measurements were conducted at ambient temperatures (T_a) between 10 and 40°C. In addition preference temperatures (PT) were determined in a temperature channel and T_b was measured at preferred T_a

2. 2.|The influence of age on T_b at constant, as well as at PT, was proved. Increasing age was accompanied by an elevation of T_b whereas HP remained constant in the mid-range of T_a

3. 3.|The lower T_b in the first days of life is suggested to result from a lower thermoregulatory set point during the postnatal period.

4. 4.|The PT were different for the observed types of behaviour. The PT at rest was higher than the PT during locomotion, food intake and drinking.

Some problems and counter-measures in modern labour. From single causal factors assessment to the analysis of multiple forms of hardship at work

1. 1. Methods are needed through which work situations can be analyzed in terms of the complex set of circumstances which they in fact involve.

2. 2. A number of office workplaces were examined with respect to both physical aspects of the work premises and the content of work. The study of task-related complaints was limited to those which are related to aspects of office work conducted using computer terminals (VDT work).

3. 3. For the purpose of illuminating the combined importance of office design and working conditions of the VDT work, the study considered the occurrence of complaints related to both sources.

4. 4. A questionnaire study (containing about 250 questions) covering all employees in eight workplaces and 269 people in total, of which 195 were VDT operators.

5. 5. The concepts, source of complain, type of complaint and were used to provide an analysis of the composite picture of complaints.

6. 6. A combination of premises-related and VDT-related complaints applies to a large number of office workers and only a few people stated were wholly free from difficulties.

7. 7. The findings indicate that by also taking account of the design of office premiss as a source of hardship, we have obtained further report for the view that the pattern of complaints is rather complicated in the case of most people who devote themselves to VDT work.

8. 8. Climatic problems arise extremely frequently, as too do problems in obtaining an appropriate balance between privacy and social contact at work.

Circadian change of heat loss in response to change in core temperature in rats

1. 1.|Circadian changes in heat production (M), heat loss (H), core temperature (T_c) and feeding activity (FA) of ad-lib fed rats were observed by direct and indirect calorimetry.

2. 2.|M, H and T_c showed a clear nocturnal increase associated with several discrete increases.

3. 3.|Whereas the slope of M vs T_c relation did not change appreciably within a day, the slope of H vs T_c or thermal conductance vs T_c relation tended to decrease at night, implying that the correlation between heat loss and body temperature is also a function of time of day in rats.

Exercise performance of normothermic and hyperthermic rats: Effect of warm rearing

1. 1.|Hypothalamic and rectal temperatures were recorded in 8 warm-reared (wr) and 12 control rats. Rats ran to exhaustion at a constant speed of 1.5 km h⁻¹ but at a variable ambient temperature adjusted to stabilize their hypothalamic temperature at 38.0°C (normothermia) or 41.0°C (hyperthermia). Blood lactate concentrations were determined before and after exercise.

2. 2.|Exercise caused exhaustion in normothermic control rats after 62.08 ± 5.43 min and in wr rats after 29.64 ± 2.09 min.

3. 3.|Hyperthermia shortened to one half (to 12.24 ± 1.36 min) and to one fourth (to 16.15 ± 1.20 min) the endurance time in wr and control rats, respectively.

4. 4.|There were no correlations between lactate concentraion and hyperthermia or endurance time.

5. 5.|In conclusion, in rats and other animals which have safe refuges, hyperthermia interferes with the ability to continue exercising.

A relationship between heat load and plasma enzyme concentration

1. 1. The sensitivity of serum enzyme levels as indicators of tissue damage is less well established in the prodromal period of heatstroke, especially for sub-lethal stress conditions.

2. 2. Anaesthetized rats were exposed to two different sets of thermal conditions.

3. 3. Plasma levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine kinase (CK) and lactate dehydrogenase (LD) were assayed in each group upon termination of stress, 6 h post-stress and 24 h post-stress.

4. 4. The tissue “damage” sustained was mild to moderate and completely reversible.

5. 5. The rate of rise in body temperature may constitute an important factor in the ultimate pathology.

6. 6. CK proved to be the most sensitive parameter of tissue “damage”.

Effects of temperature on tilt evoked swimming in the crabs Carcinus and Macropipus

1. 1.|Integrated muscle activity, total number of limb beats and the maximum instantaneous limb beat frequency were measured in crabs during a standardized tilt regime at a series of different water temperatures between 10 and 25°C.

2. 2.|Total integrated activity and total number of limb beats showed a general increase for a decrease in temperature in all groups. Frequency of limb beat was always higher for Macropipus depurator than for Carcinus maenas, with M. depurator showing an increase and C. maenas a decrease in frequencies at extreme temperatures.

3. 3.|The temperature of acclimation of C. maenas affected the response of the crab in all parameters studied while all the results can be related to the size and normal environmental temperature range of the two species studied.

A study on exposure to ultraviolet rays during outdoor sports activity

1. 1. Intensities of ultraviolet rays (UV) from every direction and the amount of UV absorbed by each body part was measured in four situations (track, beach, golf course and skiing slope).

2. 2. The intensity of UV was measured by a portable UV meter and the amount of UV absorbed by every body part was measured with a UV irradiation energy measurement label.

3. 3. The intensity of UV was strong from S45° and SE45° in all cases. On snow, the intensity of UV from every direction was stronger than in other situations, it was especially strong in reflection from below and from the north. The UV reflection from the sand was slightly larger than that from mud and grass.

4. 4. The experimental day's weather was fine and occasionally cloudy during golf, beach activity and gate-ball, and clear during skiing.

5. 5. The UV deal of a horizontal plane was 135, 98, 156 and 120 kJ/m²/h at golf, beach activity, gate-ball and skiing, respectively.

6. 6. This study suggests that players should be concerned with the prevention of UV radiation during sporting activity.

A physio-anthropological study of the POS system space scanner

1. 1. We compared the functions of POS system scanners by measuring electromyograms and joint angles during scanning in this paper.

2. 2. We have demonstrated that the space scanner is physically easy to use, movement of the wrist is natural and easy, the most suitable method for scanning perishable foods which spill easily or are fragile.

3. 3. A space scanner can be used with a bar code.

4. 4. Electromyograms were taken from M. deltoideus, M. biceps brachii, M. extensor carpi radialis longus and brevis, M. flexor carpi ulnaris muscles.

Employment of a turbidimetric assay system to measure heat-induced protein aggregation

1. 1.|We developed a turbidimetric assay system for quantitation of heat-induced protein aggregation which is presumably caused by protein denaturation.

2. 2.|Rhodanese in 6 M guanidinium chloride was employed in the assay system, because this protein recognizes hydrophobic sites on denatured proteins and aggregates.

3. 3.|Turbidity caused by protein-rhodanase aggregation was recorded at 320 nm by using a u.v./VIS spectrophotometer.

4. 4.|When heated, alcohol dehydrogenase (ADH) aggregates with rhodanese. The increase of ADH-rhodanese aggregation was correlated with the loss of enzymatic activity.

5. 5.|These results indicated that the aggregation was proportional to the extent of ADH denaturation which assumingly caused the loss of ADH activity during heating at 45.5°C.

6. 6.|Similar results were observed when cytosolic proteins from CHO cells were heated at 45.5°C. Heated cytosolic proteins promoted aggregation by complex formation with rhodanese. The aggregation increased with increasing heat dose.

7. 7.|Therefore, the rhodanese assay system can be employed usefully to quantitate the protein aggregation after heat stress.

An experimental study of effects of low-level sound in our daily life on a mental task

1. 1. It is often reported that any sound from the neighborhood disturbs one's reading or study, even though it is at a low level.

2. 2. This study was done to clarify the mechanism by which the low level sound in our daily life exerts an influence upon mental tasks.

3. 3. Two experiments were carried out, one by an ordinary, and the other by a social psychological test. In both, a random number generation test was applied as the mental exercise. The levels of presented sounds in each condition were 34–45 dBA in Leq.

4. 4. One of various conditions was in conformity with a setting of“low level noise”, where existence of low level sound is not recognized as an inevitable phenomenon but perceived as the noise.

5. 5. The quality of performance tends to be worse, though the quantitative side can be maintained.