Assessment of occupational hazards and associated risks in fuzzy environment: A case study of a university chemical laboratory

University laboratories involve various occupational hazards during the research and course activities, which might affect health and safety of both researchers and students, including chemical, physical, electrical, mechanical, as well as ergonomic and psychosocial risk factors. There are many aspects open to improvements in Occupational Health and Safety management of laboratories, and it is required to deal with risks, reduce them in an acceptable level, and implement control measures. In this study, a risk assessment approach is proposed for the university laboratory operations. The proposed approach incorporates 5S methodology, failure modes and effects analysis (FMEA), interval type-two fuzzy sets (IT2FSs), analytic hierarchy process (AHP), and the VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR). AHP is injected into IT2FSs in the phase of evaluation and weighting of severity (S), occurrence (O), and detectability (D) parameters of FMEA. By applying IT2FVIKOR, it is aimed at prioritizing the emerged hazards in the chemical laboratory of the observed university. The proposed approach reveals the important hazards and suggests control measures for managing them. The study methodologically contributes to risk assessment in the knowledge, while a case study in a chemical laboratory of a newly established university offers an insight into education industry in safety improvement.     

ABC3 Part II: a review of the new criteria for evaluating cervical cytology in England

R.G. Blanks
ABC3 Part II: a review of the new criteria for evaluating cervical cytology in England The new Achievable Standards, Benchmarks for Reporting, and Criteria for Evaluating Cervical Cytopathology, 3rd edn (ABC3) includes radical changes in the criteria for evaluating cervical cytology. First, they include a new mission statement ‘the objective of cervical screening is to reduce cervical cancer incidence and mortality by screening with a high sensitivity for the detection of CIN2 or worse, whilst maintaining a high specificity’. Second, the original four performance measurement criteria where laboratories were examined further if they were below the 10th or above the 90th percentile has been changed to three and laboratories are only mandatorily examined if they fall below the 5th or above the 95th percentile. The old criteria related to the percentage of samples that were inadequate, the percentage of all adequate samples reported as moderate dyskaryosis or worse (equivalent to high‐grade squamous intraepithelial lesion or cancer), the percentage of adequate samples reported as mild dyskaryosis or borderline (equivalent to low‐grade squamous intraepithelial lesion or atypical squamous/glandular cells) and the positive predictive value. The new criteria are percentage of inadequate samples, positive predictive value and a new measure termed referral value. These changes mean that far fewer laboratories will require mandatory examination. Third, a raft of optional performance measures have been introduced to help laboratories examine their annual statistical return to the Department of Health in comparison with other laboratories. These measures have been designed to produce a more uniform national programme, and to help laboratories decide whether they are maximizing the benefit of screening while minimizing the harm, which is the goal of all screening programmes. This review examines in detail the new criteria and explains in more detail some of the thinking behind them.     

A Multi-Variate framework to assess reliability and discrimination power of Bayesian estimation of Intravoxel Incoherent Motion parameters

PurposeTo propose a multivariate multi-step framework for a systematic assessment of the estimation reliability and discriminability of Intravoxel Incoherent Motion (IVIM) model parameters.MethodsMonte-Carlo simulations were generated on a range of SNRs and in different IVIM combinations considering: i) a dense discretization with 24 b-values; ii) a discretization with 9 b-values. A state-of-the-art Bayesian fitting method was adopted. The framework assessed: i) the best model between mono- and bi-exponential, through the BIC index; ii) the fitting accuracy; iii) the power in discriminating two different IVIM parameters distributions of estimated coefficients, using a multivariate test. Exemplificative oncologic cases were also presented.ResultsThe bi-exponential fitting was reliable for perfusion fraction higher than 5%, with high accuracy in D estimation, acceptable error for f, but high uncertainty in D*. The discrimination of two distributions is generally feasible if differences in D values (at least 0.3 x10^-3 mm²/s) are present; in the case of similar D values, a minimal difference of 5% in f can be discriminated just in case of balanced sample size and dense b-values discretization, whereas the impact of D* is quite negligible. These results were also supported by clinical examples.ConclusionsIVIM model is generally accurate in estimating diffusion, but uncertainties related to perfusion estimation are not negligible and compromise the discrimination power when different populations should be differentiated. The proposed framework should be adopted as interpretative guidelines to better understand when IVIM model applied on real data can provide reliable findings.     

Stress During Adolescence Shapes Performance in Adulthood: Context‐Dependent Effects on Foraging and Vigilance

Exposure to chronic stress during adolescence can shape behaviour, cognition and physiology in adulthood, but the consequences of these long‐term changes remain unclear. Prior studies reporting altered performance following exposure to stress in adolescence have generally interpreted lasting changes as impairments. However, we have recently shown that exposure to chronic unpredictable stress during adolescence (from post‐natal days 30–70) can enhance performance in a context‐dependent manner during a foraging task. Increases in foraging performance, (previously measured by the number of rewards obtained), are often associated with trade‐offs in other behaviours, such as vigilance. Here, we examined the effect of stress exposure in adolescence on adult foraging in male Sprague Dawley rats to determine (1) whether the increase in foraging performance exhibited by animals exposed to stress in adolescence is balanced by a decrease in vigilance, and (2) whether stress in adolescence alters time allocation between foraging and vigilance behaviours in low‐ and high‐threat conditions. We found no evidence of a trade‐off between foraging and vigilance; under low‐threat conditions, rats exposed to stress in adolescence spent more time being vigilant compared with unstressed rats, suggesting that exposure to stress in adolescence enhances anticipation of threat in adulthood. Under high‐threat conditions, adolescent‐stressed and unstressed rats did not differ in foraging and vigilance behaviours. Given that we have previously found that rats exposed to stress in adolescence nearly double food intake under high‐threat, and we now show that high‐performing rats do not spend more time foraging, it appears that stress exposure in adolescence may enhance foraging efficiency (food consumed/time) under high‐threat conditions rather than time allocation between foraging and competing behaviours. We also examined the relationship, at the level of the individual, between foraging performance and foraging and vigilance behaviours. We found that changes in individual foraging performance between low‐ and high‐threat conditions were independent of behavioural changes (i.e. both highly and poorly performing rats were equally active and contacted a similar number of patches). This suggests that the ability to obtain many rewards under high‐threat conditions may be related to efficiency, rather than the frequency of foraging and effort‐related behaviours.     

Diagnostic accuracy of cytology and immunocytology in carcinomatous effusions

Background: Immunocytology substantially improves the diagnostic accuracy of conventional cytology in the diagnosis of carcinomatous effusions. Due to the unequivocal characterization of the various cell populations, a sensitivity of 92% and specificity of 100% was achieved by immunocytology, examining samples of 1234 serous effusions. Objective: Cytology plays a central role in the aetiological clarification of serous effusions. The sensitivity of this method for the diagnosis of carcinomatous effusions varies between 40% and 80%. The aim of the present study was to investigate whether immunocytology substantially improves the diagnostic quality of the cytological examination in the diagnosis of carcinomatous effusions. Method: Consecutive serous effusions were examined by conventional cytology and by immunocytology. The immunocytological examination was performed on smears, using a standard panel of three antibodies against pancytokeratin, human epithelial antigen 125 and calretinin. Results: Altogether, 1234 effusion samples were examined. A total of 603 effusions were caused by carcinomas, five by malignant mesotheliomas, 11 by malignant lymphomas and 615 by non‐malignant disorders. In conventional cytology, carcinomatous effusions were correctly diagnosed in 314 samples, corresponding to a sensitivity of 52%. In 31 specimens (5%) tumour cells without further specification were described and in 161 samples (27%) the presence of tumour cells was suspected (84% overall sensitivity). A total of 97 carcinomatous effusions (16%) were diagnosed false‐negatively and 50 (8%) of the 615 non‐malignant effusions false‐positively (92% specificity). In immunocytology, 561 carcinomatous samples were correctly diagnosed, representing a sensitivity of 93%. In six cases (1%) the presence of tumour cells was suspected. A total of 36 carcinomatous effusions (6%) were diagnosed false‐negatively (94% over‐all sensitivity). Out of the 615 non‐malignant specimens, there were no false‐positive diagnoses (100% specificity). Conclusion: Immunocytology is a simple, cost‐effective, routinely practicable method which substantially improves the diagnostic accuracy of conventional cytology in the diagnosis of carcinomatous effusions. Therefore, we recommend the use of immunocytology in all those cases where cytology on its own is not completely unequivocal.     

Biophysical studies of phase separation integrating experimental and computational methods

Biomolecular phase separation that contributes to the formation of membraneless organelles and biomolecular condensates has recently gained tremendous attention because of the importance of these assemblies in physiology, disease, and engineering applications. Understanding and directing biomolecular phase separation requires a multiscale view of the biophysical properties of these phases. Yet, many classic tools to characterize biomolecular properties do not apply in these condensed phases. Here, we discuss insights obtained from spectroscopic methods, in particular nuclear magnetic resonance and optical spectroscopy, in understanding the molecular and atomic interactions that underlie the formation of protein-rich condensates. We also review approaches closely coupling nuclear magnetic resonance data with computational methods especially coarse-grained and all-atom molecular simulations, which provide insight into molecular features of phase separation. Finally, we point to future methodolical developments, particularly visualizing biophysical properties of condensates in cells.     

Influence of inbreeding in the early stages of artificially reared colonies of Bombus terrestris

In the present study on the bumblebee Bombus terrestris, we investigated the influence of inbreeding on queen fitness by comparing diapause survival and egg-laying success of queens mated with nestmate and non-nestmate males. We then compared the early stage of colonies with or without diploid males and analysed colony characteristics to identify a factor predictive of colony outcome. Diapause survival was no different between queens mated with nestmates and non-nestmates, but in the latter case, egg-laying success was significantly higher. Queens mated with nestmates gave rise to a percentage of diploid male colonies (52.6%) compatible with brother–sister coupling. We obtained 18.6% of colonies with diploid males even from queens mated with non-nestmates, indicating that the colonies of origin were in some way related or homozygous at the sex determination loci. There was no difference in the early growth stage between colonies with or without diploid males, except in the number of workers emerging in the first brood, which was significantly higher in the latter. Among diploid male colonies, the number of workers and the male/worker ratio in the first brood was highly variable and was not a good predictor of subsequent colony growth. Out of 49 colonies with diploid males that reached full development, only 11 had a sufficient size to assume that they could survive in the field or, in a commercial breeding, to be suitable for pollination purposes.     

实验用鱼遗传质量控制及标准化

在遗传学及其他生命科学研究领域, 实验用鱼已成为一类应用越来越广的实验动物, 但是尚缺少标准化的质量控制标准和监管。在我国, 实验动物实行严格的许可证制度和质量监督制度。实验用鱼遗传质量控制标准是实验用鱼质量控制的基础。为了规范实验用鱼的遗传质量, 避免实验用鱼种质退化、遗传漂移, 导致实验结果误差, 开展了本标准的研究。依据《实验动物管理条例》, 参考国内外实验用鱼遗传学相关的研究成果, 结合我国实验用鱼生产和使用的实际情况, 在全面收集、分析实验数据和广泛征询专家意见的基础上, 以实验用斑马鱼和剑尾鱼遗传质量控制为规范对象, 研究制定了实验用鱼遗传质量控制标准, 供科研工作者参考、讨论。本标准对实验用斑马鱼和剑尾鱼的遗传分类及命名原则、实验用鱼的繁殖方法、近交系和封闭群的遗传质量监测进行了规范。新标准将为实验用鱼的使用和管理提供理论支撑。