Acoustic comfort depends on the psychological state of the individual

Recent studies have shown that comfort can be influenced more by psychological processes than from the characteristics of environmental stimulation. This is relevant for different industrial sectors, where comfort is defined only as a function of the intensity of external stimuli. In the present study, we measured physiological and psychological comfort during the exposure to four levels of acoustic noise [from 45 to 55 dB(A)] corresponding to different comfort classes inside a full-scale mock-up of a cruise ship cabin. We found an increase of psychological and physiological discomfort for higher noise intensities, but not for all the intensities defining the comfort classes. Furthermore, we found that negative psychological states determine a lower physiological sensitivity to acoustic noise variations compared to positive states. Our results show that, at normal/low intensities, psychological processes have a greater role in determining acoustic comfort when compared to the stimulus intensity. Practitioner Summary: This study shows that psychological factors can be more relevant in determining acoustic comfort inside a ship cabin than the intensity of acoustic stimulus itself. This finding suggests that the cruise industry should consider not only the engineering measurements when evaluating comfort on board, but also the passenger\u2019 psychological state. Abbreviations: AIC: akaike information criterion; CCT: colour correlated temperature; cd/m2: candela/square meters; df: degrees of freedom; F-test: Fisher's test; HF: high frequency; HR: heart rate; HRV: heart rate variability; HSV: hue saturation value; K: kelvin; LF: low frequency; LF/HF: low frequency to high frequency ratio; lme: linear mixed effects; ms: milliseconds; nu: normalized unit; p: p value; pNN50: percentage of adjacent pairs of normal to normal RR intervals differing by more than 50 milliseconds; r2: coefficient of determination; rc: concordance correlation coefficient; RMSSD: square root of the mean normal to normal RR interval; SD: standard deviation; SDNN: standard deviation of normal to normal RR intervals; SEM: standard error of the mean; t-test: student's tests; \u3c72: chi-square test

Symptoms and musculoskeletal diseases in hospital nurses and in a group of university employees: a cross-sectional study

Background. Most studies have shown that nurses have a higher risk of developing musculoskeletal symptoms compared with other occupational groups. Aim. A cross-sectional study was performed to gain more insight into the prevalence rates of musculoskeletal disorders (MSDs) in nurses. Methods. The presence of musculoskeletal symptoms was revealed by personal interviews in a sample of 177 hospital nurses and in a reference group of 185 university employees. Musculoskeletal diseases were based on radiological examinations in all subjects. Results. Lower back pain (61% vs 42.2%) was the most frequently reported symptom, followed by neck pain (48.6% vs 38.4%) and shoulder pain (36.7% vs 25.9%), with a significantly higher prevalence in nurses. Women had about a 2-fold risk of upper limb region and neck pain compared with men. The most common abnormal findings on radiological examinations were disc herniations (n = 40). Conclusions. Nurses showed a significantly higher risk of MSDs. Prevalence rates in nurses increased significantly with age. Musculoskeletal symptoms were also common in university employees. This suggests the need for effective intervention strategies involving workers\u2019 active participation, in order to improve the process and organization of work and promote a positive psychosocial work environment

A longitudinal study of finger systolic blood pressure and exposure to hand-transmitted vibration

Objectives To investigate prospectively the relation between vibration-induced white finger (VWF), exposure to hand-trasmitted vibration (HTV) and the cold response of digital arteries in users of vibrating tools. Methods Two-hundred and sixteen HTV workers and 133 control men of the same companies underwent initially a medical examination and a standardised cold test with measurement of the change in finger systolic blood pressure (FSBP) after finger cooling from 30 to 10C. They were re-examined 1 year later. Tool vibration magnitudes were expressed as frequency-weighted and unweighted r.m.s. accelerations. From the vibration magnitudes and exposure durations, alternative measures of cumulative vibration dose were calculated for each HTV worker, according to the expression: dose \ubc Pami ti, where ai is the acceleration magnitude on tool i, ti is the lifetime exposure duration for tool i, and m = 0, 1, 2 or 4. Results Among the HTV workers, the initial prevalence and the 1-year incidence of VWF were 18.1 and 1.7%, respectively. At the first examination, the HTV workers with moderate or severe score for VWF showed a significantly increased cold reaction in the fingers when compared with the controls and the HTV workers with no vascular symptoms. At the follow-up, the controls, the asymptomatic HTV workers, and the prevalent cases of VWF did not show significant changes in the cold response of digital arteries. A deterioration of cold-induced digital vasoconstriction was found in the incident cases of VWF. In the HTV workers, vibration doses with high powers of acceleration (i.e., dose \ubc Pami ti with m[1) were major predictors of the vasoconstrictor response to cold at the follow-up examination. Conclusions The measurement of FSBP after local cooling may be a helpful objective test to monitor prospectively the change in vibration-induced vascular symptoms. The findings of this longitudinal study suggest a dose\u2013effect relationship between cold-induced digital arterial hyperresponsiveness over time and measures of cumulative vibration exposure. In the controls, the cold response of the digital arteries was stable over 1-year follow- up period

Use of color charts for the diagnosis of finger whiteness in vibration-exposed workers

Objectives To assess the usefulness of color charts for the diagnosis of finger whiteness in vibration-exposed workers. Methods A group of 146 forestry and stone workers exposed to hand-transmitted vibration (HTV) were examined twice over 1 year follow up period. The anamnestic diagnosis of finger whiteness was made on the basis of (a) a medical history alone, and (b) the administration color charts which showed changes in the skin color of fingers and hands. The cold response of digital arteries was assessed by measuring the change in finger systolic blood pressure (FSBP) after local cooling from 30 to 10C (FSBP%10). Results Assuming the administration of color charts as the gold standard, the sensitivity and specificity of the medical history alone to diagnose finger whiteness was 88.2 and 93.8%, respectively, at the initial cross-sectional study and 94.4 and 97.7% at the end of the follow-up. Random-intercept linear regression analysis of follow up data showed that after adjustment for several covariates, FSBP%10 was significantly associated with finger whiteness assessed by either medical history alone (P\0.005) or the color charts (P\0.001). However, a statistical measure of overall fit of regression models (Bayesian Information Criterion) suggested that the color chart method performed better than medical history alone for the prediction of the cold response of digital arteries. Conclusion The administration of color charts seems to reduce the proportion of false positive responses for finger whiteness in a population of vibration-exposed workers. The color chart method was a more significant predictor of digital arterial hyperresponsiveness to cold than medical history alone. These findings suggest that the use of color charts in clinical and epidemiological studies may be of help to assist in the diagnosis of finger whiteness in vibration-exposed workers

Antiapoptotic and antigenotoxic effects of N-acetylcysteine in human cells of endothelial origin

N-Acetylcysteine (NAC) is a drug bearing multiple preventive properties that can inhibit genotoxicity and carcinogenicity. NAC also inhibits invasion and metastasis of malignant cells, as well as tumor take. We recently demonstrated the effects of NAC on Kaposi's sal coma cells supernatant-induced invasion in vitro and angiogenesis in vivo. Many anticancer agents act through cytotoxicity of rapidly proliferating cells and several antineoplastic drugs induce apoptosis of cancel cells. Since endothelial cells are the target for the inhibition of angiogenesis, we wanted to verify that NAC, while inhibiting tumor vascularization and endothelial cell invasion would not induce endothelial cell apoptosis. We tested the ability of NAC to modulate apoptosis and cytogenetic damage in vitro and to promote differentiation on a reconstituted basement membrane (matrigel) in two endothelial cell lines (EAhy926 and HUVE). Treatment with NAC protected endothelial cells from TGF-beta -induced apoptosis and paraquat-induced cytogenetic damage. Therefore, NAC acts as an antiangiogenic agent and, at the same time, appeals to pl event apoptosis and oxygen-related genotoxicity in endothelial cells