An Ensemble of Deep Learning Object Detection Models for Anatomical and Pathological Regions in Brain MRI

This paper proposes ensemble strategies for the deep learning object detection models carried out by combining the variants of a model and different models to enhance the anatomical and pathological object detection performance in brain MRI. In this study, with the help of the novel Gazi Brains 2020 dataset, five different anatomical parts and one pathological part that can be observed in brain MRI were identified, such as the region of interest, eye, optic nerves, lateral ventricles, third ventricle, and a whole tumor. Firstly, comprehensive benchmarking of the nine state-of-the-art object detection models was carried out to determine the capabilities of the models in detecting the anatomical and pathological parts. Then, four different ensemble strategies for nine object detectors were applied to boost the detection performance using the bounding box fusion technique. The ensemble of individual model variants increased the anatomical and pathological object detection performance by up to 10% in terms of the mean average precision (mAP). In addition, considering the class-based average precision (AP) value of the anatomical parts, an up to 18% AP improvement was achieved. Similarly, the ensemble strategy of the best different models outperformed the best individual model by 3.3% mAP. Additionally, while an up to 7% better FAUC, which is the area under the TPR vs. FPPI curve, was achieved on the Gazi Brains 2020 dataset, a 2% better FAUC score was obtained on the BraTS 2020 dataset. The proposed ensemble strategies were found to be much more efficient in finding the anatomical and pathological parts with a small number of anatomic objects, such as the optic nerve and third ventricle, and producing higher TPR values, especially at low FPPI values, compared to the best individual methods.

A comprehensive survey of deep learning research on medical image analysis with focus on transfer learning

This survey aims to identify commonly used methods, datasets, future trends, knowledge gaps, constraints, and limitations in the field to provide an overview of current solutions used in medical image analysis in parallel with the rapid developments in transfer learning (TL). Unlike previous studies, this survey grouped the last five years of current studies for the period between January 2017 and February 2021 according to different anatomical regions and detailed the modality, medical task, TL method, source data, target data, and public or private datasets used in medical imaging. Also, it provides readers with detailed information on technical challenges, opportunities, and future research trends. In this way, an overview of recent developments is provided to help researchers to select the most effective and efficient methods and access widely used and publicly available medical datasets, research gaps, and limitations of the available literature.

A tuber calcanei avulsion fracture developed on the basis of idiopathic osteoporosis in a young male: a case report

Calcaneus fractures constitute 1.2 % of all fractures. Tuber calcanei avulsion fractures constitute 1.3-2.7 % of calcaneus fractures. Osteoporosis, osteomalacia, and diabetes mellitus have been reported to increase the risk of development of these fractures. It has been reported that tuber calcanei avulsion fractures in elderly females might develop due to osteoporosis. As far as we know, no tuber calcanei avulsion fracture developing on the basis of osteoporosis without presence of a trauma has been reported in young males in the literature. In the current case report, a 41-year-old male patient who was admitted with complaints of pain in the left heel and diagnosed with calcaneal avulsion fracture that developed on the basis of idiopathic osteoporosis and who was treated with conservative methods was presented.

Effect of polyethylene glycol induced drought stress on photosynthesis in two chickpea genotypes with different drought tolerance

Responses of parameters related with photosynthesis and the involvement of various factors in photosynthetic damage in two chickpea genotypes, Gokce (tolerant) and Kusmen (sensitive) under drought stress were assessed. Photosynthetic pigment content decreased under drought stress in two genotypes. Significant decreases in gs, Pn and E were determined in Kusmen. No significant change in these parameters was measured in Gokce under drought stress. Fv/Fm, ΦPS2 and ETR decreased in drought stressed plants of Kusmen as compared to control plants however Fv/Fm, ΦPS2 and ETR did not change in Gokce under drought stress. Increases in NPQ were determined under stress in both genotypes. Drought stress did not affect rubisco activity and rubisco concentration in Gokce while, the activity and the content declined in Kusmen. The drought tolerance of the Gokce genotype is a consequence of a balance among leaf water potential, stomatal conductance, photosynthesis, and transpiration. On the other hand, photosynthesis in Kusmen may be not only restricted by stomatal limitations but also by non-stomatal limitations under drought stress.

Rotational Molding of Polyamide-6 Nanocomposites with Improved Flame Retardancy

The aim of this work was to develop polyamide-6/ organic-modified montmorillonite (omMMT) nanocomposites for the production of hollow parts by rotational molding. Particular emphasis was placed on the mechanical and flame retardancy properties needed for the fabrication of vessels for flammable liquids. The morphology of the melt compounded nanocomposites, produced by melt compounding, was investigated by X-ray diffraction measurements (WAXD), and Transmission Electron Microscopy (TEM) showed an exfoliated structure. Rheological measurements were used in order to verify whether the viscosity of materials was adequate for rotational molding. While thermomechanical analysis has revealed that neat PA6 and its nanocomposites were not suitable for rotational molding, due to the very low thermal stability of the polymer, the addition of a thermal stabilizer, shifted the onset of degradation to higher temperatures, thus widening the processing window of both PA6 and PA6 nanocomposites. Large-scale vessel prototypes were obtained by rotational molding of thermo-stabilized PA6 and its nanocomposites, and samples extracted from the rotomolded parts were characterized with respect to physical and mechanical properties. It was found that the PA6 nanocomposites exhibited significant improvements at cone calorimeter tests in comparison with neat PA6.

Application of mathematical modelling for assessing the urinary half-times of nickel in stainless steel welders

The study regards workers employed in manual metal are welding of stainless steel (MMA/SS). For two weeks they collected their urine during the work shift and the 16 hours following in order to evaluate the kinetics of nickel. Using one-compartment mathematical modelling we calculated the values of the toxicant's urinary half life during the two phases of exposure and postexposure and also during non working weekends. The aim of the study was to find correlations between inhaled doses and excreted quantities and to acquire practical data for use in biological monitoring. In the welders the mean urinary half life in the exposure period was 59.5 hours, in the post exposure it was 95.6 hours, while in weekend it was 95.5 hours. The study showed that exposure to fumes containing nickel could determine the accumulation of the metal in slow elimination speed compartment. As a consequence of the accumulation of nickel in compartments with different elimination speeds, the collection of single urinary portions in biological monitoring seems to give little information about the actual exposure. In our opinion this indicates collecting urine samples throughout the entire work shift and the 16 hours following exposure.

Characterization of the kinetic behavior of resin modified glass-ionomer cements by DSC, TMA and ultrasonic wave propagation

In this study the isothermal kinetic behavior of two resin modified glass ionomer cements (RMGIC) and a dental composite have been compared by differential scanning calorimetry (DSC) and thermo-mechanical analysis (TMA). The simultaneous evolution of the multiple reactions occurring in RMGIC has been analyzed not only by DSC and TMA but also by ultrasonic wave propagation using the pulse-echo technique. The propagation of ultrasonic waves, acting as a dynamic mechanical deformation at high frequencies, is proportional to the longitudinal bulk moduli of the material and may be used to measure the changes of mechanical properties induced by a chemical reaction as occurs in RMGIC. TMA and ultrasonic analysis have been used to monitor the acid-base reaction of RMGIC in dark conditions. Moreover an RMGIC presenting a double reactive mechanism in dark conditions, a thermally activated radical polymerization and an acid-base reaction are studied using these experimental techniques. Finally DSC and TMA results obtained during photopolymerization of an RMGIC and of a dental composite have been compared.

[A case of pleural mesothelioma caused by unusual occupational exposure to asbestos in the wool industry]

We report the case of a 73-year-old worker who died of pleural mesothelioma, after being employed for 35 years in a wool textile plant of Biella (Italy). Close investigations revealed that he provided for the maintenance of materials and machines. In particular, he used to replace asbestos parts such as rings, joints and insulations of pipelines (dyeing unit), as well as brake linings of warping, looming and combing machines. Beside confirming the importance of an accurate occupational anamnesis to recognize work-induced cancers, the case draws the attention on the risk of mesothelioma in the wool industry, an occupational setting that is not usually considered as a potential source of exposure to asbestos fibres. Such pollution might explain the increased mortality due to pleural mesothelioma in the Biella area (characterized by a prosperous textile industry), reported in previous epidemiological studies.

Quantitative assessment of changes in blood CO(2) tension mediated by the haldane effect

Adequate assessment of circulatory and gas-exchange interactions may involve the quantification of the Haldane effect (HE) and of the changes in blood PCO(2) mediated by changes in Hb-O(2) saturation and O(2)-linked CO(2) binding. This is commonly prevented by the complexity of the involved calculations. To simplify the task, a large series of patient measurements has been processed by regression analysis, thus developing an accurate fit for this quantification (v-a) PCO(2)HE + 0.460 [(a-v) HbO(2)]0.999e0.015(PvCO(2))-0.852(Hct) (n = 247, r(2) = 0. 99, P << 0.001), where (v-a)PCO(2 HE) is the reduction in venous PCO(2) (Pv(CO(2)), Torr) allowed by the chemical binding of CO(2) in blood due to the HE (Torr), (a-v)HbO(2) is the arteriovenous difference in Hb-bound O(2) (ml/dl), and Hct is hematocrit fraction. Values of (v-a)PCO(2 HE) estimated by this expression compared well with the results of previously published experiments. This formula is useful in assessing the impact of HE on Pv(CO(2)) and venoarterial PCO(2) gradient and the survival advantage offered by HE in extreme conditions. Use may be extended to all investigative and clinical settings in which changes in blood O(2) saturation and O(2)-linked CO(2) binding must be converted into the corresponding changes in dissolved CO(2) and PCO(2).

[Retrospective study of morbidity in a group professionally exposed to chlorotriazine herbicides]

Two different groups of workers involved, during the last 10 years, in the production or formulation of chlorotriazine herbicides have been retrospectively studied in order to verify the occurrence of diseases possibly related to Atrazine, Simazine, Propazine and Terbuthylazine exposure. A control group has been selected between clerical workers of the same plants. Exposure data have been collected during the last five years and some extrapolations have been performed to hypothesize the level of exposure in the preceeding years. Clinical findings and laboratory data obtained from ten year medical surveillance records have been evaluated to highlight possible differences between the investigated groups. A first close examination of the data concerning the anamnesis and clinical, hematochemical and functional reports of the three groups of investigated subjects does not show any pathological situation or symptoms specifically connected to chlorotriazine compounds exposure and/or significant differences between exposed and non exposed. A next series of statistical surveys involving some of the hematochemical indicators (RBC, WBC, Hb%, SGOT, SGPT, gamma GT) has been performed either on internal values of each group or on the average-values of the three groups differently exposed (production, formulation, control). The first survey was a longitudinal study, the second one was a cross sectional one. Both the investigations have excluded significant differences attributable to the occupational exposure.

[The biological monitoring of those exposed to 1,1,1-trichloroethane: a longitudinal study]

Data on long-term biological monitoring in two groups of workers engaged in cleaning operations in a wool factory and exposed to methylchloroform are presented. The longitudinal survey lasted one year and brought about 19 random systematic sampling (once or twice a month for everyone of the 13 subjects monitored). The biological marker adopted was the urinary concentration of the solvent as such, according to a previously studied method. The collected data allowed to measure: the annual average level of exposure (estimated by the long term geometric mean); the day to day variation of the true daily exposure averages (estimated by the geometric standard deviation); the probability of overexposure (daily exposures exceeding the biological exposure limit) and the yearly number of work shifts of overexposure. The usefulness of performing long-term surveys of occupational exposure to the chemical substances by mean of longitudinal biological monitoring is discussed.

Low incidence of bleeding from HIV-related thrombocytopenia in drug addicts and hemophiliacs: implications for therapeutic strategies

The records of 608 intravenous drug addicts and 124 hemophiliacs diagnosed in 1985 to be seropositive for HIV were reviewed to identify patients with thrombocytopenia. The records of 54 drug addicts (8.9%) and 14 hemophiliacs (11.2%) who had chronic thrombocytopenia were then followed through June 1989 to estimate the incidence of bleeding episodes. The records of 55 HIV-seronegative patients with idiopathic thrombocytopenic purpura (ITP), comparable for age, platelet count at diagnosis and duration of follow-up, were used for comparison. Patients with ITP were significantly different from those with HIV-associated thrombocytopenia in having a higher proportion of females (M/F ratio 13/42 v 53/15, p less than 0.001) and more intensive treatment (treated: 62% v 21%, p less than 0.001; splenectomized 37% v 1.5%, p less than 0.001). The incidence of major bleeding was not significantly different in drug addicts, hemophiliacs and ITP patients (0.98, 1.82 and 1.17/100 patients/year). Among drug addicts, bleeding was significantly more frequent in women than in men (3.4 v 0/100 patients/year, p less than 0.05). Our results indicate that the incidence of major bleeding in patients with HIV-associated thrombocytopenia is low and similar to that observed in more intensively treated ITP patients.

[The evaluation of the individual thermal load in work activity with uneven energy expenditure]

It is often very difficult to quantify the potential thermal stress in jobs characterized by sudden variations of energy expenditure and thermal overload for time periods of short duration. Heart rate varies rapidly with the changes of energy expenditure and thermal load and the application of the mathematical model, proposed by Givoni and Goldmann for prediction of heart rate response to work in hot environments, to values of the physiological parameter, continuously measured during the periods of work and rest, allows the calculation of the two components of the HSI stress index (Er, Emax) from which to derive safe times of exposure. In this study practical applications of the theoretical method are verified in the control of the potential thermal stress of workers engaged in the carbon coke production. In that job the variability of thermal conditions make unfeasible a complete and whole evaluation of thermal overload only based on the measure of the microclimatic environmental parameters.

[Evaluation of thermal comfort in a student population: predictive value of an integrated index (Fanger's predicted mean value]

Practical applications and predictive values of a thermal comfort index (Fanger's PRV) were verified on a sample school population (1236 subjects) by studying the relationships between thermal sensations (subjective analysis), determined by means of an individual questionnaire, and the values of thermal comfort index (objective analysis) obtained by calculating the PMV index individually in the subjects under study. In homogeneous conditions of metabolic expenditure rate and thermal impedence from clothing, significant differences were found between the two kinds of analyses. At 22 degrees C mean radiant and operative temperature, the PMV values averaged 0 and the percentage of subjects who experienced thermal comfort did not exceed 60%. The high level of subjects who were dissatisfied with their environmental thermal conditions confirms the doubts regarding the use of the PMV index as a predictive indicator of thermal comfort, especially considering that the negative answers were not homogeneous nor attributable to the small thermal fluctuations (less than 0.5 degree C) measured in the classrooms.

[Evaluation of individual thermal load in working environments with non-homogeneous microclimatic conditions]

It is often very difficult to quantify the potential thermal stress of jobs requiring high worker mobility in unevenly hot environments. The determination of integrated indexes such as HSI can be a cause of error in risk evaluation. However, monitoring of physiological parameters of exposed workers, such as internal body temperature, provides a direct expression of man-environment interaction. On the basis of measurement of micro-climatic parameters and internal body temperature of subjects employed in a glass production plant, an attempt was made to calculate an integrated index of thermal stress risk which reflected the job requirements. The mathematical model used was the one proposed by Givoni and Goldman for prediction of rectal temperature and heart rate response to work in hot environments.

[Assessment of risk in occupational tasks with exposure to environmental noise of variable duration and intensity]

The discontinuous exposure to environmental working noise often brings about risk situations hardly assessable by means of phonometric measurements and studying the exposure time, even if accurate. The use of the personal dosimetry can simplify the measurements and give a time-weighted value (Leq) comparable to a fixed limit value. Such a measurement is effective only for the considered time (usually a work shift); nevertheless it is assumed to be representative of the usual exposure to the job even though the variability of the working conditions constitute a limiting factor. In this work we tried to verify the possible use of the measurements of environmental sound pressure levels given by the dosimeter every 0.25 sec. The first aim being the study of the type of distribution of these values (during 5 consecutive shifts) and the estimate of mean and standard deviation values. The mean and the standard deviation values were used to get a OTL (one sided tolerance limits) usually employed for assessing the working chemical pollution. The second aim being the compliance control and the possible need of more measurements.

[Importance of the relative humidity values in determining thermohygrometric comfort]

A condition of discomfort with specific symptoms, such as throat dryness, eye irritation, in a group of workers of a small, air conditioned, working department, is described. Neither the measurements of the possible environmental pollutants concentrations, nor the assessment of the usually adopted comfort indexes (PMV-PPD) justified the worker's symptoms. They completely disappeared by means of appropriate environmental improvements aiming to increase the relative humidity values from 29% to 50-55% (drop of the amount of the hygroscopic material stored, setting up of an humidifier). The effects of the low humidity values on the hygrometric and thermal comfort are finally discussed.

[Monitoring of occupational activities under the risk of heat stress: use of mathematical models in the prediction of physiological parameters]

Some authors proposed mathematical models that, starting from standardized conditions of environmental microclimate parameters, thermal impedance of the clothing, and energetic expenditure allowed the forecast of the body temperature and heart rate variations in respect to the basal values in subjects standing in the same environment. In the present work we verify the usefulness of these models applied to the working tasks characterized by standardized job made under unfavourable thermal conditions. In subject working in an electric power station the values of the body temperature and heart rate are registered and compared with the values obtained by the application of the studied models. The results are discussed in view of the practical use.

[Prospects for environment intervention following biological monitoring of exposure to chromium]

The authors study the statistical distribution and the graphical representation of the urinary chromium values investigated during three consecutive years in three work environments of a same plant: polishing 1 degree, electrotyping, polishing 2 degrees, to evaluate the environmental situations of exposure and their variations. The adopted method, based on the graphical representation of the values in logarithmic coordinate paper, allows to quickly and carefully calculate the percent of the workers having urinary chromium values above the prefixed limits.

[Validity of a biophysical model for predicting heart rate values during activities operating under a risk of thermal stress]

After measuring the heart rate values of workers unfolding a standardized job made under unfavourable microclimatic conditions, the Authors calculate them by application of a proposed biophysical model starting from ambient climatic conditions, energetic expenditure and thermal resistance of the clothing. The results, compared by means of statistical methods, do not show any significant difference between the two methods. Therefore is also possible the proposal of the use of the biophysical model for the prevision of heart rate under standardized working conditions.

[Reference values of chromium urine in the population residing in Lombardy]

The accurate determination of Cr in normal human urine still presents a considerable challenge, connected to its very low content, supposedly about 1 ppb. The analytical data obtaining from many Authors varying between 0.3 microgram/day and 150 micrograms/day. The question now arises which data picture the true Cr content of normal human urine. To this purpose we have determined the content of total urinary chromium in 310 healthy individuals (170 male, 140 female) resident in Lombardy (Italy). A mean urinary Cr concentration of 0.59 +/- 0.26 ppb was obtained. The levels of urinary chromium tended to be higher in males than in females and to decrease with age.

[Control of duration limits of work activity at risk in thermal stress by prediction of values for internal body temperature]

A biophysical model for studying the response of the rectal temperature to changes in metabolic rate and environmental conditions has been utilized to establish the safe exposure times for works at risk of thermal stress. The prediction of the rectal temperature allows to evaluate for how long the heat load due to metabolic rate is lasting after the work stopping in the period of recovery.

[Use of a biophysical model to verify various methods for limiting the time of work activity at risk in thermal stress]

The Authors measure the environmental microclimatic parameters (dry bulb temperature, wet bulb temperature, globe temperature, natural wet bulb, air speed, vapor pressure) in twenty working sites. Starting from the values obtained, they calculate the safe exposure times for works under unfavourable thermal conditions by means of three different methods (time weighted average WBGT, allowable exposure time-AET, required sweat rate index). Finally they verify the results obtained by application of a biophisical model proper to calculate the response of rectal temperature to changes in metabolic rate and environmental conditions.

[Decrease in environmental pollution and changes in biological indicators in occupational exposure to lead]

The Authors examine the variations of the levels of PbB and EPP in 39 workers at known lead exposure and evaluate the capacity of these parameters to follow the measured decreases of the environmental pollution. They conclude that the variations of the mean PbB values are well related to environmental pollution and that the diagram on the probability paper of median values and their corresponding standard deviations allows to calculate the number of exposed workers with biological values above a fixed limit.

Hepatic function in subjects exposed to environmental concentrations of DMF lower than the actually proposed TLV

Hepatic function investigation in 54 workers, exposed to an airborne concentration of DMF lower than TLV in an acrylic fiber plant, has been carried out. The results suggest the probable absence of hepatic cytolysis phenomena for this degree of exposure.

[Changes in spontaneous platelet aggregation induced by the ambient temperature]

The diagnostic meaning of the functional platelets modifications (particularly those of spontaneous platelet aggregation = P.A.) in cardiovascular pathology has been recalled. It is emphasized that, in order to have significantly predictable data on eventual pathological alterations in case of deviations of values considered normal, one has to use methods that do not differ from the real haemorheological conditions. A research has therefore been made with the purpose to evaluate the influence that variations of temperature may have on the samples collected and left to sediment (for the separation of the PRP) and the subsequent modifications of P.A. The research has been made in double on plasma sedimented at 37 degrees C and at room-temperature on 731 subjects, 289 of which were the casuistic groups for the subsequent statistic elaboration. With similar modalities in other 8 patients the eventual variations in excretion of beta-TG were looked for. The results have shown that there are important variations of the spontaneous P.A. rates, that the difference is always statistically very significant and that lowering the temperature of the samples favors an increase in beta-TG excretion . The Authors think therefore that only the sedimentation at 37 degrees C issues a plasma usefull for the further performing of platelets tests, while in the plasma obtained with sedimentation at room-temperature the platelets are perhaps already stimulated to an activation (and subsequently an aggregation) higher than the real one. Data obtained from a homogeneous group of subjects, healthy from a clinical point of view, allowed to fix the new range of normal values within 3% of aggregability . The mechanisms that lead to such different results are discussed. Emphasis is put on the fact that the spontaneous P.A. determined by the means mentioned seems satisfactorily near to the real clinical conditions. That's why the hypothesis arises that also other tests concerning platelet functions could be negatively influenced if they have room-temperature as a condition for plasma separation.

[Control of cardiac frequency in work activity at risk of thermal stress]

The working time in work places termically uncomfortable must be limited in order to prevent the risk of thermal stress; the safe exposure times are based on the microclimatic parameters and the energetic expenditure required for the job. Hearth rate measure is proposed by various Authors as index connected with the energetic expenditure level and with the microclimatic conditions. In the present work the Authors realise the monitoring of a job uncomfortable for thermal conditions by means of the hearth rate measure of the workers. The results show the better accuracy of the purposed method in comparison with the application of the safe exposure times.

[Microclimatic indexes and limits of safe exposure in work activity at risk of thermal stress]

The working time in work places thermically uncomfortable must be limited in order to prevent the risk of thermal stress. In a previous study we have demonstrated that the best method for calculation of the safe exposure times is based on the required sweat rate index. In the present work we verified in different work places termically uncomfortable, grouped for equivalent values of WBGT index, the variability of the safe exposure times calculated by means of a method just now mentioned for various levels of energetic expenditure. The results point out the possibility of a mathematical relation between energetic expenditure, WBGT index and mean of safe exposure times.

[Thermal balance in workers of in greenhouses for the cultivation of tropical plants]

The Authors starting from the microclimatic parameters globe temperature (tg), dry bulb temperature (ts) forced wet bulb temperature (tu), natural wet bulb temperature (tun), speed of the air (v) observed every half an hour in greenhouses for tropical plants, evaluate the required sweating rate per hour during a specimen working shift for a known energetic expenditure. The sweating rate values calculated exceed by far the highest limits accepted for the workers perfectly acclimatized and impose the application of the working safe exposure times.

[Relation between thermal comfort indices and various values of thermal impedence for clothes]

The Authors show that there is some relationship between WBGT microclimatic index and PMV thermic comfort index. This relationship can be noticed at various levels of energetic expenditure and for three values of thermic impedance from clothes used in working places in the four seasons.

[Microclimate and duration of work tolerance in hothouse for cultivation of tropical plants]

The AA. starting from the environmental values carried out in a greenhouse for tropical plants investigate the possibility of prevent the risk of thermal stress at standardized energetic expenditures by means of the measurement of a few microclimatic parameters; they elaborate also a nomogram proper to calculate the safe exposure times for works under unfavourable thermal conditions.

[Duration limit of moderately heavy work activity in technically unfavorable environments]

The working time in work places thermically uncomfortable must be limited in order to prevent the risk of thermal stress. The Authors measure the environmental microclimatic parameters (dry bulb temperature, wet bulb temperature, globe temperature, natural wet bulb temperature, air speed, vapor pressure) in twenty working sites of a thermal power plant. Starting from the values obtained, they calculate the safe exposure times under unfavourable thermal conditions by means of four different methods (WBGT, time weighted average WBGT, allowable exposure time-AET, required sweat rate index). The results are critically analysed.

[Threshold of energy expenditure for maintenance of thermal comfort in working areas]

The Authors test the possibility of improving the microclimatic conditions of some working areas by assessing the threshold energetic expenditure (KCal/hour and KCal/min) in order to maintain the thermic well-being by means of a "thermic comfort" parameter, PMV. For this purpose, we measured PMV on the basis of tg, ts, V, tun, Pa and Clo in 15 working areas. Then, by an iterative mathematical process, we calculated the threshold value of energetic expenditure in accordance with the values of PMV which show conditions of thermic comfort, that is between + 0.5 and - 0.5. In all the working areas observed it is possible to perform works requiring energetic expenditures lower than 200 KCal/h in conditions of thermic comfort; in 50% of the situations we examined even works requiring higher energetic expenditures.

[Simplification of periodic audiometric tests in persons exposed to industrial noise. An operative proposal]

Today the pure tonal audiometric test is the most used in periodical screening of the "hypoacusis" hazard in exposed patients because of its easy performance. The high number of patients to be tested and the screening frequency suggested to simplify the annual checks by testing only some of the frequency to be tested is made on the basis of the first complete audiogram performed according to a scheduled scheme. Available screening data and testing on the field show that a consistent reduction in testing time is possible and that the complete exam is reliable.

[Acute poisoning by Vantal (combination of dimethoate and DDT) in a group of longshoremen]

In this work the authors describe a case of acute intoxication by "VANTAL" (DDT and Dimethoate) occurred in a group of six longshoremen. The authors particularly consider the reports about the gastroenteric apparatus and the central and peripheric nervous system. It has in fact been possible to document all kinds of pathologic condition from gastritis to duodenal ulcer in all subjects; whereas only three subjects out of six showed alterations in E.E.G. and E.M.G.