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In this study, we simulated the performance of solar cells using appropriate optical and electrical parameters for MoX2 compounds. We used the solar cell capacitance simulator software to simulate MoS2-based solar cells with two structures (ZnO/WS2/MoS2 or ZnO/WSe2/MoS2). We investigated the impact of varying the thickness of the MoS2 absorbing layer, doping, temperature elevation, and exploring the effect of the buffer layer on the electrical characteristics of the solar cell, including parameters like open-circuit voltage (Voc), short-circuit current (Jsc), and solar cell efficiency (η). This analysis aimed to provide valuable insights into optimizing the design and performance of MoS2-based solar cells, contributing to advancements in thin-film solar cell technology. [ABSTRACT FROM AUTHOR]

Bubble Technology Industries (BTI) has built a revolutionary portable neutron scintillation spectrometer, N-Probe, designed to be used by non-specialists for measurement of low-intensity neutron doses in the mixed field environments often found in nuclear utilities, fuel storage areas, fuel and waste processing operations and military applications. It is compatible with the current generation of BTI MICROSPEC analysers and shares the philosophy of spectral dosimetry with other BTI spectroscopic probes, where the dosimetric quantities are computed from the spectrum using appropriate fluence-dose conversion functions. [ABSTRACT FROM PUBLISHER]

Abstract: After considering epidemiological studies on the induction of cataracts in individuals exposed to radiation, the International Commission on Radiological Protection recommended, in 2012, a reduction in the annual eye-dose limit of occupationally exposed workers. This imposed higher performance demands on existing dosimetry systems and the development of new dosimetry technologies. The operational quantity to be measured is Hp(3), the personal dose equivalent at a depth of 3 mm in an ICRU 4-element tissue cylinder 20 cm in height and 20 cm in diameter. The conversion coefficients per unit incident fluence, Hp(3)/Φ, were calculated using Monte Carlo simulation codes. In the case of incident electrons, the literature shows that the resulting coefficients depend on the electron transport options selected for the Monte Carlo simulations as well as the tally zone thickness. In this study, electron operational eye-lens dose coefficients were calculated using MCNP6.2 in its default settings and by invoking the single-event feature. The results were compared to those from PENELOPE, a well-known code for its enhanced accuracy in handling low-energy electron transport. The results are in agreement for the entire energy range for these two series of simulations, but differences are found with previously published dose coefficients in the literature. This impacts the calibration of dosimeters for electrons and may require a change in the commonly accepted dose coefficients., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 Health Physics Society.)

This paper is a continuation of a study published recently by the authors. It presents and discusses computed personal absorbed dose in the lens of the eye ( D p lens / Φ ), and a relative biological effectiveness (RBE)-weighted absorbed dose (in terms of an newly proposed operational quantity RBE × D p lens / Φ ), conversion coefficients for the lens of the eye for neutron exposure at incident energies from thermal to ∼20 MeV and at angles of incidence from 0 ° to 90 ° in 15° increments, at 180° and for rotational incidence irradiation geometry (from 0 ° to 360 ° in 5 ° increments). These conversion coefficients were obtained from a simulation model developed for this study that contains the stylised eye model, embedded in the adult UF-ORNL mathematical phantom, whereby the previously stated RBE-weighted absorbed dose was obtained using the proposed RBE versus neutron energy distribution compiled in a previous paper by the authors. The simulations carried out for this study using the Monte Carlo N-Particle transport code version 6.2, were conducted in a realistic human eye model, for the left and right sensitive and whole volume of the lens of the eye, considering the recent proposed redefinition of the operational quantities for external radiation exposure in International Commission on Radiation Units and Measurements (ICRU) report 95. A comprehensive set of tabulated data for neutron fluence-to-dose conversion coefficients ( D p lens / Φ in pGy cm 2 ) and RBE-weighted absorbed dose (RBE × D p lens / Φ in pGy cm 2 ) conversion coefficients is included in this paper as a function of incident neutron energy and angle of incidence. Data for D p lens / Φ (pGy cm 2 ) are compared to similar data from the literature for validation of our model. Data for RBE × D p lens / Φ (in pGy cm 2 ), were also compared to the equivalent operational quantity H p (3,α)/ Φ (in pSv cm 2 ) conversion coefficients calculated at 3 mm depth in a cylindrical phantom for different incident neutron energies and angles of incidence from 0 ° to 75 ° in 15 ° increments to demonstrate the relevance of this newly proposed operational quantity for doses resulting in tissue reactions (deterministic effects) which should be quoted in Gray (RBE-weighted absorbed dose, RBE × D (Gy)), rather than Sievert (Sv) which is reserved for stochastic effects. The current neutron weighted absorbed dose (RBE × D p lens ) is proposed for the tissue reactions in the eye-lens for neutron radiation as per National Council on Radiation Protection and Measurements report 180 and in line with the recent proposal for the review and revision of the System of Radiological Protection to Keeping the International Commission on Radiological Protection (ICRP) recommendations fit for purpose. This method would bring better alignment between the dose limits in ICRP 118 and the new operational quantity consistent with the units of the new eye-lens dose limits without being overly conservative. The utilization of the proposed new operational quantities, as outlined in ICRU 95, has the potential to address the ongoing challenge in enforcing regulatory limits for neutron eye dose, specifically the use of Gy instead of Sv. It should be noted that the applicability of this will vary from country to country as in many countries the legislation is likely to mandate the use of H p (3) until the regulation is amended. This approach can serve as an interim solution while awaiting the issuance of the new ICRP general recommendations, which is expected to take several years. Implementing the new operational quantities can contribute to enhancing the accuracy and effectiveness of neutron eye dose limit enforcement., (© 2023 Society for Radiological Protection. Published on behalf of SRP by IOP Publishing Limited. All rights reserved.)

In 2012, the International Commission on Radiological Protection issued new recommendations, in publication 118, regarding the dose limits to the eye-lens. New analyses of historical exposure data had indicated that radiation-induced cataracts may appear at lower doses than previously assumed. This spurred largescale efforts in a variety of fields including dosimetry, radiation effects simulations, and the review of national regulatory limits. On the simulation side, much work led to the publication of dose rate conversion factors (DRCFs), to calculate the dose to the radiosensitive part of the eye-lens, and to the whole eye-lens as functions of the incident fluence of electron, photon, positron, and neutron radiation. The standard, ISO-15382 (2015 Radiological Protection-Procedures for Monitoring the Dose to the Lens of the Eye, the Skin and the Extremities ), from the International Organization for Standardization (ISO), stated that the direct contact of a hot radioactive particle on the eye-lens represents a special contamination condition that must be considered. The aim of this work was to produce tabulated data of eye-lens dose rates, per activity (MBq), for a variety of radionuclides. In this work, the dose to the eye-lens from contamination directly in contact with the cornea, expressed in terms of DRCFs for eye-lens, in units of Gy h -1 MBq -1 , are presented for 102 radionuclides of interest. These radionuclides were selected as they had been considered by the International Atomic Energy Agency of importance for skin dose. The method consisted of two steps. The first was the determination of the DRCFs for mono-energetic electrons and photons for a hot particle in contact with the eye-lens, followed by the folding of these quantities with the emissions of the radionuclides of interest. Contributions from spontaneous fission neutrons were considered separately. Exposure geometries for spherical hot particles of different dimensions, materials and locations on the cornea were considered. In addition, partial surface coverage of the cornea, consistent with an accidental exposure to a contaminated liquid, was also modelled. Resulting radionuclide DRCFs were verified, for a few specific geometries and radionuclides with dedicated Monte Carlo simulations. The final data are presented in several tables included in this paper., (© 2023 Society for Radiological Protection. Published on behalf of SRP by IOP Publishing Limited. All rights reserved.)

For planned occupational exposure situations, the International Commission on Radiological Protection (ICRP) publication 118 recommends an equivalent dose limit for the lens of the eye of 20 mSv yr -1 averaged over 5 yr with no single year exceeding 50 mSv. Regulatory authorities of various jurisdictions worldwide followed some or all, of the ICRP recommendations and implemented reduced occupational lens of eye dose limits in their legislation. As compliance with the eye-lens dose limit will be based on the summation of doses received from all types of radiation, applicable to a variety of workplaces, the contribution of neutrons to eye lens dose will be important where it contributes a significant fraction of the total dose to the eye lens. This work presents and discusses computed personal absorbed dose ( D lens /Φ), and personal dose equivalent ( H p (3)/Φ) as well as a newly proposed relative biological effectiveness (RBE)-weighted absorbed dose (RBE × D lens /Φ) conversion coefficients for the lens of the eye for neutron exposure at incident energies from thermal to ∼20 MeV. The D lens /Φ coefficients were obtained from a simulation model developed for this study that contains the stylised eye model embedded in the adult UF-ORNL mathematical phantom. The modelling techniques used in these simulations were also used to calculate H p (3)/Φ for the International Commission on Radiation Units and Measurements (ICRU) slab and cylinder phantoms. All simulations carried out for this study utilised the Monte Carlo N-Particle (MCNP) series of codes. The results are compared with the related published data. The issue of compliance with the current equivalent dose limit for the lens of the eye is addressed from a neutron perspective considering the recent proposed redefinition of the operational quantities for external radiation exposure in ICRU report 95. The use of a radiation weighted absorbed dose (RBE × D lens , in Gy) is proposed for the tissue reactions in the eye-lens for neutron radiation as per the National Council on Radiation Protection and Measurements report 180, and in line with the recent review and revision of the System of Radiological Protection To Keeping the ICRP Recommendations Fit for Purpose, which states that RBE weighted dose should be used for high-Linear energy transfer (LET) radiations such as neutrons. This confirms the earlier statement in ICRP publication 92, paragraph 297 and reiterated in the Executive summary, paragraph (q) of ICRP publication 118. The proposed approach would provide an operational quantity consistent with the units of the new eye-lens dose limits without being overly conservative., (© 2022 Society for Radiological Protection. Published on behalf of SRP by IOP Publishing Limited. All rights reserved.)

For occupational exposures in planned exposure situations International Commission on Radiological Protection (ICRP) publication 118 recommends an equivalent dose limit for the lens of the eye of 20 mSv yr -1 averaged over five years with no single year exceeding 50 mSv. This constitutes a reduction from the previous limit of 150 mSv yr -1 . The Canadian nuclear regulator, the Canadian Nuclear Safety Commission, responded to the ICRP recommendation by initiating amendments to the Radiation Protection Regulations through a discussion paper which was published for comment by interested stakeholders in 2013. The revised equivalent dose limit of 50 mSv in a one-year dosimetry period for nuclear energy workers came into effect in January 2021. This paper presents the outcome of discussions with Canadian stakeholders in diverse fields of radiological work which focused on the implementation of the reduced occupational equivalent dose limit for the lens of the eye in their respective workplaces. These exchanges highlighted the existing practices for monitoring doses to the lens of the eye and identified current technological gaps. The exchanges also identified that, in many cases, the lens of the eye dose is anticipated to be well within the new dose limit despite some of the gaps in technology. The paper also presents the monitoring and eye-lens dose assessment solutions that are available based on different methods for eye-lens monitoring; presented together with criteria for their use., (© 2022 Society for Radiological Protection. Published on behalf of SRP by IOP Publishing Limited. All rights reserved.)

Aim: The aim of this study was to provide information on the prevalence of Salmonella serotypes and to identify risk factors for Salmonella spp. contamination in broiler chicken farms and slaughterhouses in the northeast of Algeria., Materials and Methods: This study was conducted on 32 poultry farms and five slaughterhouses in the province of Skikda (northeastern Algeria). A questionnaire was answered by the poultry farmers and slaughterhouses' managers. Biological samples (cloacal swabs, droppings, caeca, livers, and neck skins) and environmental ones (water, feed, surface wipes, rinsing water, and sticking knife swabbing) were taken to assess the Salmonella contamination status., Results: Nearly 34.37% of the poultry farms and all the slaughterhouses were contaminated with Salmonella . The isolated Salmonella strains belonged to two major serotypes: Kentucky and Heidelberg followed by Enteritidis, Virginia, and Newport. There was an evident heterogeneous distribution of serotypes in poultry farms and slaughterhouses. Only one factor (earth floor) was significantly associated with Salmonella contamination in poultry houses (p<0.05)., Conclusion: A high prevalence rate of Salmonella contamination was found in poultry farms and slaughterhouses in Skikda region. These results showed the foremost hazardous role of poultry production in the spread and persistence of Salmonella contamination in the studied region.

Background: The aims of this study were to investigate Salmonella contamination in broiler chicken farms and slaughterhouses, to assess the antibiotic resistance profile in avian and human Salmonella isolates, and to evaluate the relationship between avian and human Extended Spectrum β-Lactamase (ESBL)-producing isolates. Salmonella was screened in different sample matrices collected at thirty-two chicken farms and five slaughterhouses. The human isolates were recovered from clinical specimens at the University Teaching Hospital of Constantine (UTH). All suspected colonies were confirmed by MALDI-TOF (Matrix Assisted Laser Desorption Ionization Time OF light) and serotyped. Susceptibility testing against 13 antibiotics including, amoxicillin/clavulanic acid, ticarcillin, cefoxitin, cefotaxime, aztreonam, imipenem, ertapenem, gentamicin, amikacin, ciprofloxacin, colistin, trimethoprim/sulfamethoxazole and fosfomycin, was performed using the disk diffusion method on Mueller-Hinton agar. ESBL-production was screened by the double-disk synergy test and confirmed by molecular characterization using PCR (polymerase chain reaction) amplification and sequencing of ESBL encoding genes. Clonality of the avian and human strains was performed using the Multi Locus Sequencing Typing method (MLST)., Results: Forty-five isolated avian Salmonella strains and 37 human collected ones were studied. Five S. enterica serotypes were found in avian isolates (mainly Kentucky) and 9 from human ones (essentially Infantis). 51.11% and 26.6% of the avian isolates were resistant to ciprofloxacin and cefotaxime, respectively, whereas human isolates were less resistant to these antibiotics (13.5% to ciprofloxacin and 16.2% to cefotaxime). Eighteen (12 avian and 6 human) strains were found to produce ESBLs, which were identified as bla CTX-M-1 (n = 12), bla CTX-M-15 (n = 5) and bla TEM group (n = 8). Interestingly, seven of the ESBL-producing strains (5 avian and 2 human) were of the same ST (ST15) and clustered together, suggesting a common origin., Conclusion: The results of the combined phenotypic and genotypic analysis found in this study suggest a close relationship between human and avian strains and support the hypothesis that poultry production may play a role in the spread of multidrug-resistant Salmonella in the human community within the study region.