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Abstract Background Addicted patients undergoing methadone maintenance treatment are prone to several complications and the risk of relapse. Objective The present study aims to investigate the effect of cranial electrotherapy stimulation on depression, anxiety, and craving in addicted male people undergoing methadone maintenance treatment. Methods This randomized controlled trial study was conducted on 60 male patients referred to Persia addiction treatment center between 2021 and 2022. Patients were randomly divided into two equal treatment and placebo groups. The treatment group received cranial electrotherapy stimulation intervention for 48 sessions of 30 min. Depression and anxiety were evaluated using the Hamilton questionnaire before and after the intervention, and the level of craving was also evaluated with the Federdi 2008 questionnaire. Results Comparing the level of depression and anxiety before and after the intervention in both treatment and placebo groups did not show any significant difference (p

The Lower Red Formation (LRF) in Central Iran consists of the alternation of red-brown terrigenous sediments, marls and evaporites with basalt intercalations, exposed under the Chattian-Burdigalian Qom Formation and deposited on Eocene volcaniclastic sediments. The LRF is considered Rupelian in age. In the Deh Nar area, between Qom and Kashan cities, the LRF includes a basal conglomerate, alternations of brown-red sandstone and shale, colored marls with evaporite diapirs and top eroded red sandstone, with dark gray and green basalt lava intercalations. These sedimentary rocks are deposited in fluvial and playa environments, influenced by volcanic activities. Lower sandstone layers of the LRF in Deh Nar contain numerous vertebrate footprints, mostly preserved as convex hyporeliefs. Bird footprints are identified as Ardeipeda egretta, Aviadactyla vialovi, Avipeda phoenix and Gruipeda dominguensis. Small bird footprints are attributed to small, incumbent anisodactyl shoreline birds, such as sandpipers, and the larger of them to Gruiformes and Ciconiiformes, such as Ardeidae and Ciconiidae. Mammal footprints include Dehnaripus incognitus ign. nov. and isp. nov., Lophiopus isp., Moropopus elongatus, Moropopus kashanensis isp. nov., Platykopus stuartjohnstoni, and Zanclonychopus isp. Dehnaripus incognitus is large circular manus and pes imprints; usually, they show unorganized, large, radial surface wrinkles and their digital or metatarsal/ metacarpal imprints are ambiguous. Moropopus kashanensis is tridactyl mammal pes and manus imprints and is distinguished by sharp, claw-like imprints in lateral digits of the manus from Moropopus elongatus. Most probably, the mammal tridactyl footprints of Deh Nar made by three toed, medium- to large sized terrestrial herbivores perissodactyls such as Tapiroidea. Platykopus and Zanclonychopus, however, were remained by large carnivores such as Amphicyonidae or Ursidae. Trackmakers of footprints in the LRF of Deh Nar area lived under hot and dry conditions of terrestrial and evaporitic environments, after cool and dry conditions of the Early Oligocene.

Abstract Background One of the main risks of infection after hematopoietic stem cell transplantation (HSCT) is infection by gram-positive bacteria, including vancomycin-resistant enterococci (VRE). Based on the format of a global review and meta-analysis study, this study aims to investigate the incidence of VRE bloodstream infection (BSI) after HSCT in colonized individuals. Methods The keywords of the systematic search included vancomycin-resistant enterococci and HSCT. These words were searched in Google Scholar, PubMed/Medline, Scopus, and Web of Science databases from January 1, 2000, to March 1, 2024. Studies that reported the prevalence of vancomycin-resistant enterococci in patients undergoing HSCT were included. The random effects model was used for the meta-analyses. Investigations were conducted according to PRISMA guidelines, and the protocol was registered in PROSPERO: CRD42024543491. Results Out of 1100 screened papers, 28 were eligible. The random effects model was established to analyze the incidence of VRE BSI after HSCT. The pooled prevalence of co-infection for Allo-HSCT recipients was 3.023 (95% CI, Z-value = -3.5, p-value

Abstract Objective Neurological and functional impairments are commonly observed in individuals with spinal cord injury (SCI) due to insufficient regeneration of damaged axons. Exosomes play a crucial role in the paracrine effects of mesenchymal stem cells (MSCs) and have emerged as a promising therapeutic approach for SCI. Thus, this study aimed to evaluate the safety and potential effects of intrathecal administration of allogeneic exosomes derived from human umbilical cord MSCs (HUC-MSCs) in patients with complete subacute SCI. Methods This study was a single-arm, open-label, phase I clinical trial with a 12-month follow-up period. HUC-MSCs were extracted from human umbilical cord tissue, and exosomes were isolated via ultracentrifugation. After intrathecal injection, each participant a underwent complete evaluation, including neurological assessment using the American Spinal Injury Association (ASIA) scale, functional assessment using the Spinal Cord Independence Measure (SCIM-III), neurogenic bowel dysfunction (NBD) assessment using the NBD score, modified Ashworth scale (MAS), and lower urinary tract function questionnaire. Results Nine patients with complete subacute SCI were recruited. The intrathecal injection of allogeneic HUC-MSCs-exosomes was safe and well tolerated. No early or late adverse event (AE) attributable to the study intervention was observed. Significant improvements in ASIA pinprick (P-value = 0.039) and light touch (P-value = 0.038) scores, SCIM III total score (P-value = 0.027), and NBD score (P-value = 0.042) were also observed at 12-month after the injection compared with baseline. Conclusions This study demonstrated that intrathecal administration of allogeneic HUC-MSCs-exosomes is safe in patients with subacute SCI. Moreover, it seems that this therapy might be associated with potential clinical and functional improvements in these patients. In this regard, future larger phase II/III clinical trials with adequate power are highly required. Trial registration Iranian Registry of Clinical Trials, IRCT20200502047277N1. Registered 2 October 2020, https://en.irct.ir/trial/48765 .

Abstract Strain- and defect-engineering are two powerful approaches to tailor the opto-electronic properties of two-dimensional (2D) materials, but the relationship between applied mechanical strain and behavior of defects in these systems remains elusive. Using first-principles calculations, we study the response to external strain of h-BN, graphene, MoSe2, and phosphorene, four archetypal 2D materials, which contain substitutional impurities. We find that the formation energy of the defect structures can either increase or decrease with bi-axial strain, tensile or compressive, depending on the atomic radius of the impurity atom, which can be larger or smaller than that of the host atom. Analysis of the strain maps indicates that this behavior is associated with the compressive or tensile local strains produced by the impurities that interfere with the external strain. We further show that the change in the defect formation energy is related to the change in elastic moduli of the 2D materials upon introduction of impurity, which can correspondingly increase or decrease. The discovered trends are consistent across all studied 2D materials and are likely to be general. Our findings open up opportunities for combined strain- and defect-engineering to tailor the opto-electronic properties of 2D materials, and specifically, the location and properties of single-photon emitters.

Abstract This study explores defect engineering in 2D materials using ion beam irradiation to modify the electrical and optical properties with potential in advancing quantum electronics and photonics. Helium and neon ions ranging from 5 to 7.5 keV are employed to manipulate charge transport in monolayer molybdenum disulfide (MoS2). In situ electrical characterization occurs without vacuum breakage post‐irradiation. Raman and photoluminescence spectroscopy quantify ion irradiation's impact on MoS2. Small doses of helium ion irradiation enhance monolayer MoS2 conductivity in field‐effect transistor geometry by inducing doping and substrate charging. Findings reveal a strong correlation between the electrical properties of MoS2 and the primary ion used, as well as the substrate on which the irradiation occurred. Using hexagonal boron nitride (h‐BN) as a buffer layer between MoS2 flake and SiO2 substrate yields distinct alterations in electrical behavior subsequent to ion irradiation compared to the MoS2 layer directly interfacing with SiO2. Molecular dynamics simulations and density functional theory provide insight into experimental results, emphasizing substrate influence on measured electrical properties post‐ion irradiation.

Abstract Background Premature ejaculation is one of the most common male sexual dysfunction, affecting approximately 30% of men. The aim of this study is to evaluate the efficacy and at the same time the safety of the cranial electrotherapy stimulation (CES) device in treatment of premature ejaculation disorder. Methods Based on a randomized clinical trial, two groups were included in the study, so that the first group was treated with sertraline along with an ATANG (AT-9 model) CES, and the second group with sertraline and inactive the CES device (as the placebo group). The state of premature ejaculation after treatment (using the Premature Ejaculation Diagnostic Tool (PEDT) questionnaire) was evaluated and compared for both groups. Results In the intervention and placebo groups, the average score of the PEDT questionnaire before the intervention did not differ significantly between the two groups (p-value equal to 0.93). However, the average score of the PEDT questionnaire after the intervention for CES group and placebo group was 10.28 ± 1.93 and 13.23 ± 3.05, respectively, which demonstrated a significant decrease in the intervention group (p-value equal to 0.01). Conclusion The use of CES device as a complementary treatment along with routine drug treatment (sertraline) is associated with a significant improvement in the condition of premature ejaculation of patients. Trial registration Name of the registry: IRCT Iranian Registry of Clinical Trials. Trial registration number: IRCT20210621051657N1. Date of registration: December 11, 2022. URL of trial registry record: https://en.irct.ir/trial/57201 .

Ruchun-Mazar region is located in southern Sanandaj-Sirjan Zone, southwest of Baft city in Kerman province, Iran. Seh Chah, Chah Sorbi, Chah Nar, Zardbazi Dar, and Chah Sorbi Arjmand Pb-Zn deposits located in this region were investigated. The most outcrops of the geological units in the area include the Paleozoic metamorphic complexes of Gol Ghohar (amphibolite, gneiss and micaschist), Ruchun (schist, marble, calcschist, black chert, slate and phyllite), and Khabar (marble, calcschist). Microdioritic, monzodioritic and diabasic dykes have intruded into the metamorphic units. Dolomitic and calcitic marble of Ruchun complex is the host rock for Pb-Zn mineralization. Primary mineralization in Seh Chah, Chah Sorbi, and Chah Nar deposits includes galena, sphalerite, and pyrite ± chalcopyrite along with quartz, calcite, and dolomite ± barite. Vein-veinlet, open space filling, brecciated ± disseminated ± laminate structures and textures can be seen in these deposits. The most important alterations in these deposits are silicification and carbonitization (calcitic and dolomitic alterations). Primary sulfide ore in Zardbazi Dar and Chah Sorbi Arjmand deposits has been weathered and mining has been carried out on nonsulfide ore (supergene ore). The nonsulfide ore formed at the expense of sulfides, and mainly consists of smithsonite, hydrozincite, hemimorphite, and cerussite. It seems that these deposits belong to the direct replacement and, to a lesser extent, wall rock replacement nonsulfide zinc deposits. Based on the geological, mineralogical and alteration evidence, the primary mineralization in the region can be divided into two groups of SEDEX type (Chah Sorbi deposit) and vein type (Chah Nar and Seh Chah deposits). It was concluded that under supergene conditions in some deposits, nonsulfide ore was also formed. Moreover, the deposits of this region can be categorized into primary sulfide (hydrothermal) and nonsulfide (supergene). Introduction Iran embraces extensive areas having high potential for carbonate-hosted (CH) Zn-Pb deposits due to the suitable geodynamic conditions and the occurrence of large carbonate platforms (Rajabi et al., 2012). A wide variety of Zn-Pb deposits have been reported along Sanandaj-Sirjan Zone (SSZ) in Iran. The development of SSZ is related to the generation of the Neo-Tethys Ocean during the Permian and its subsequent destruction due to the convergent and continental collision between the Arabian and Iran plates during Cretaceous to Tertiary periods (Mohajjel et al., 2003; Ghasemi and Talbot, 2006). Ruchun-Mazar (Rechan) region is located in the southern Sanandaj-Sirjan zone (Fig. 1). This area is located at 75 km southwest of Baft city in Kerman province, Iran. In this region, the lower paleozoic marble rocks of Ruchun complex host numerous Zn-Pb deposits (Fig. 2). Although sulfide mineralization is dominant in this region (e.g., Seh Chah, Chah Sorbi, and Chah Nar deposits), secondary non-sulfide ores are common (e.g., Zardbazi Dar and Chah Sorbi Arjmand deposits). Based on geology, mineralogy, mineralization and alteration, the similarities and differences among the Pb-Zn deposits of this region were investigated. Material and methods At the first step, a 1:50,000 integrated geological map of Ruchun-Mazar region was prepared. Then, a more detailed investigation of the deposits, including field sampling of rock units, ore veins, tunnels and other mining works was done. Field observations were supplemented by petrographic studies and X-ray powder diffraction (XRD) analysis. From the collected samples (224 samples), 95 thin sections, 48 polished thin sections, and 41 polished sections were prepared for petrographic and mineralogical studies. Twenty-eight samples (sulfide and nonsulfide ores and gossan) were analyzed by XRD at the GSI. Nonsulfide ores, which contain Zn, were identified (stained bright red) by Zinc Zap, a solution of 3% potassium ferricyanide K3Fe(CN)6 and 0.5% diethylaniline dissolved in 3% oxalic acid. Results Ruchun-Mazar mining area is located in the southern part of Sanandaj-Sirjan zone (Fig. 1). Based on stratigraphy of the region, chronological sequences from the oldest to youngest include Paleozoic Gol Gohar, Ruchun and Khabar metamorphic complexes, Permian-Triassic metamorphosed carbonates, Jurassic-Cretaceous meta flysch, Cretaceous marbles (Koh-e-Khabar), Eocene-Oligocene flysch, and Quaternary sediments (Fig. 2). Gol Gohar complex (unit Pz2) contains gneiss, micaschist and amphibolite with a probable Cambrian age which has been intruded by mafic intrusive bodies. The Ruchun complex (unit Pz3) is the host complex for lead, zinc and iron mineralizations in the region. Sequence of stratigraphic layers from bottom to the top contains Gol Gohar complex (Camberian), Ruchun complex (Camberian-Ordovician), and Khabar complex (Middle-Upper Devonian), respectively. Metamorphosed carbonate rocks (dolomitic and calcitic marbles) of Ruchun complex (Pz3d and Pz3m) are seen in brown and light to dark gray colors and often alternate associated with metamorphosed sedimentary and volcanic rocks (Pz3sch unit) (Fig. 3A). The Ruchun complex was intruded by microdiorite, monzodiorite, microgabbro, and diabase dikes (Fig. 3B). Quartz and calcite veins have cut most of the Ruchun complex units (Fig. 3C and 3D). Calcitic and dolomitic marbles with probable Permian-Triassic age (Fig. 3E and F) can be seen on Ruchun complex (units PTm and PTd). Mafic (gabbro) to felsic (granite) intrusive bodies (gabbro to granite) were exposed in the west of DehSard village, next to Permian-Triassic dolomite (Fig. 3F). Pb-Zn mineralization in the Mazar-Ruchun region is formed in the calcitic and dolomitic marble (Pz3d and Pz3m) of the Ruchun complex (Fig. 4A, B, C and D). These metamorphosed carbonates are composed of calcite and dolomite, and minor minerals such as muscovite, quartz, and opaque minerals (Fig. 4E and F). Based on the morphology of calcite blade (Burkhard, 1993), and the presence of calcite (type I and II), the temperature of metamorphism of this marble is between 250 and 350 degrees, which corresponds with the green schist facies. Marbles alternate associate with schist (green schist, mica schist and graphite schist) and phyllite (Fig. 3A, E and G). Primary mineralization in Seh Chah, Chah Sorbi and Chah Nar deposits includes galena, sphalerite, pyrite ± chalcopyrite associated with quartz, calcite, and dolomite ± barite. Vein-veinlet, open space filling, brecciated ± disseminated ± laminated structures and textures can be seen in these deposits. The most important alterations in these deposits are silicification and carbonitization (calcitic and dolomitic alterations). Carbonate host rock and structural control can be considered as the most important factors for controlling primary ore mineralization in the Seh Chah and Chah Nar Pb-Zn deposits. Dolomitic and calcitic marble in the Seh Chah deposit are highly altered (Fig. 4B). A number of basic to intermediate intrusive bodies (often as dykes) can be seen in this area. Chah Nar and Seh Chah deposits were formed epigenetically with vein-veinlet, open space filling and brecciated structures and textures (Fig. 5B and C). Graphite schist in Chah Sorbi deposit is sometimes seen alternating with marble in the Ruchun complex sequence. In this deposit, in addition to vein-veinlet, open space filling and brecciated textures (which were also observed in the Seh Chah and Chah Nar deposits), part of the ore has a laminated and disseminated textures. It seems that the type of sulfide mineralization in Chah Sorbi deposit is different from the other two deposits (Fig. 6A to C). In Chah Sorbi deposit, galena, sphalerite, pyrite and chalcopyrite associated with quartz, calcite, organic matter, dolomite and barite were deposited in the hydrothermal mineralization stage (Fig. 6D and Table 1). The effects of metamorphism and deformation in this deposit can be traced by such evidence as microscopic and mesoscopic folds and faults in the ore and host rock (Fig. 6E and F). In contrast, Chah Nar and Seh Chah deposits were formed after the last metamorphic event (probably post Late Cretaceous) and no evidence of metamorphism can be seen in them. Primary sulfide ores in Zardbazi Dar and Chah Sorbi Arjmand deposits have been weathered and mining has been carried out on nonsulfide ore (supergene ore). The nonsulfide ore formed at the expense of sulfides, and mainly consists of smithsonite, hydrozincite, hemimorphite, and cerussite (Fig. 8A and G, and Table 1). Discussion and conclusion Sediment-hosted Pb-Zn deposits represent the world’s largest accumulations of base metals (Goodfellow and Lydon, 2007; Wilkinson, 2014). Table 2 shows a comparison of the general characteristics of these deposits with Pb-Zn deposits in Ruchun-Mazar area. The host rock of the studied deposits (calcitic and dolomitic marble) is different from the SEDEX type deposits (shale as the dominant host rock). Chah Nar and Seh Chah, deposits were formed epigenetically (within fracture and fault and as replacements) and deposited after the last metamorphic event (probably post Late Cretaceous). These deposits are classified as a group of epigenetic deposits and show a significant similarity to MVT deposits, although they also display fundamental differences with this category of ore deposit (especially host rock alteration). The presence of laminated and disseminated textures (before the metamorphism event) in Chah Sorbi deposit classified it as a syngenetic to early diagenetic Pb-Zn deposit (e.g., Irish type or SEDEX). Chah Sorbi deposit shows notable similarity to Howard’s Pass district, Selwyn Basin, of sedimentary exhalative (SEDEX) Zn-Pb deposits (Gadd et al., 2017). Mineralization in Howard’s Pass district (Late Ordovician to Early Silurian) was hosted by carbonaceous, calcareous and, to a lesser extent, siliceous mudstones. Mining works in Zardbazi Dar and Chah Sorbi Arjmand deposits was carried out on nonsulfide ore (supergene ore). The supergene nonsulfide deposits are unmetamorphosed and undeformed. They consist of low-temperature and low-pressure assemblages that precipitated from meteoric fluids, replacing sulfides and carbonate groundmass to form encrustations and fill pore spaces, veins, and fractures. Some of the key controls on the formation of carbonate-hosted nonsulfide Zn-Pb deposits are the nature and availability of near-surface sulfide protore, lithology, sub-aerial exposure, tectonic uplift, climate and favorable hydrology (Hitzman et al., 2003). Hitzman et al. (2003) described two specific forms of nonsulfide ore from various nonsulfide deposits around the world: red ore and white ore. Red ore is gossanous, usually found immediately above the sulfide protore, and typically contains >20% Zn, 7% Fe and Pb, and minor silver (Simandl and Paradis, 2008). Typical red ore nonsulfide minerals include iron-oxyhydroxides, goethite, hematite, hemimorphite, smithsonite, and/or hydrozincite and cerussite (Reichert and Borg, 2008). White ore contains up to 40% Zn but less than 7% Fe and Pb. Smithsonite and hydrozincite are common minerals in white ore with only small amounts of Fe-oxyhydroxides and cerussite (Reichert and Borg, 2008). Zinc and Pb nonsulfides can be used as indirect indicator minerals in exploration for MVT, SEDEX, Irish-type, carbonate replacement, and vein-type Zn-Pb deposits. It seems that Zardbazi Dar and Chah Sorbi Arjmand deposits belong to the direct replacement and lesser extent wall rock replacement nonsulfide zinc deposits. Acknowledgments This study was done supported by a grant of Ferdowsi University of Mashhad. The study is part of the Project number 41179 and also part of the first author’s doctoral thesis. We gratefully thank Dr. Mohammad Salehi Tinoni, Mohsen Jorjandipour, Ali Rashidi, Dr. Ali Amiri and Dr. Ahmad Rashidi Bosharabadi who helped us in different field works. We are grateful to the respected reviewers who played a significant role in the scientific improvement of the article.

Abstract This study aimed to investigate the diagnostic performance of machine learning-based radiomics analysis to diagnose coronary artery disease status and risk from rest/stress Myocardial Perfusion Imaging (MPI) single-photon emission computed tomography (SPECT). A total of 395 patients suspicious of coronary artery disease who underwent 2-day stress-rest protocol MPI SPECT were enrolled in this study. The left ventricle myocardium, excluding the cardiac cavity, was manually delineated on rest and stress images to define a volume of interest. Added to clinical features (age, sex, family history, diabetes status, smoking, and ejection fraction), a total of 118 radiomics features, were extracted from rest and stress MPI SPECT images to establish different feature sets, including Rest-, Stress-, Delta-, and Combined-radiomics (all together) feature sets. The data were randomly divided into 80% and 20% subsets for training and testing, respectively. The performance of classifiers built from combinations of three feature selections, and nine machine learning algorithms was evaluated for two different diagnostic tasks, including 1) normal/abnormal (no CAD vs. CAD) classification, and 2) low-risk/high-risk CAD classification. Different metrics, including the area under the ROC curve (AUC), accuracy (ACC), sensitivity (SEN), and specificity (SPE), were reported for models’ evaluation. Overall, models built on the Stress feature set (compared to other feature sets), and models to diagnose the second task (compared to task 1 models) revealed better performance. The Stress-mRMR-KNN (feature set-feature selection-classifier) reached the highest performance for task 1 with AUC, ACC, SEN, and SPE equal to 0.61, 0.63, 0.64, and 0.6, respectively. The Stress-Boruta-GB model achieved the highest performance for task 2 with AUC, ACC, SEN, and SPE of 0.79, 0.76, 0.75, and 0.76, respectively. Diabetes status from the clinical feature family, and dependence count non-uniformity normalized, from the NGLDM family, which is representative of non-uniformity in the region of interest were the most frequently selected features from stress feature set for CAD risk classification. This study revealed promising results for CAD risk classification using machine learning models built on MPI SPECT radiomics. The proposed models are helpful to alleviate the labor-intensive MPI SPECT interpretation process regarding CAD status and can potentially expedite the diagnostic process.

Abstract In semiconductors, the identification of doping atomic elements allowing to encode a qubit within spin states is of intense interest for quantum technologies. In transition metal dichalcogenides semiconductors, the strong spin-orbit coupling produces locked spin-valley states with expected long coherence time. Here we study the substitutional Bromine BrTe dopant in 2H-MoTe2. Electron spin resonance measurements show that this dopant carries a spin with long-lived nanoseconds coherence time. Using scanning tunneling spectroscopy, we find that the hydrogenic wavefunctions associated with the dopant levels have characteristics spatial modulations that result from their hybridization to the Q-valleys of the conduction band. From a Fourier analysis of the conductance maps, we find that the amplitude and phase of the Fourier components change with energy according to the different irreducible representations of the impurity-site point-group symmetry. These results demonstrate that a dopant can inherit the locked spin-valley properties of the semiconductor and so exhibit long spin-coherence time.

Abstract Microorganisms do not live as dispersed single cells but rather they form aggregates with extracellular polymeric substances at interfaces. Biofilms are considered efficient life forms because they shield bacteria from biocides and collect dilute nutrients. This is a big concern in industry since the microorganisms can colonize a wide range of surfaces, accelerating material deterioration, colonizing medical devices, contaminating ultrapure drinking water, increasing energy costs and creating focus of infection. Conventional biocides that target a specific component of the bacteria are not effective in the presence of biofilms. Efficient biofilm inhibitors are based on a multitarget approach interacting with the bacteria and the biofilm matrix. Their rationale design requires a thorough understanding of inhibitory mechanisms that are still largely lacking today. Herein we uncover via molecular modelling the inhibition mechanism of cetrimonium 4-OH cinnamate (CTA-4OHcinn). Simulations show that CTA-4OH micelles can disrupt symmetric and asymmetric bilayers, representative of inner and outer bacterial membranes, following three stages: adsorption, assimilation, and defect formation. The main driving force for micellar attack is electrostatic interactions. In addition to disrupting the bilayers, the micelles work as carriers facilitating the trapping of 4OH cinnamate anions within the bilayer upper leaflet and overcoming electrostatic repulsion. The micelles also interact with extracellular DNA (e-DNA), which is one of the main components of biofilms. It is observed that CTA-4OHcinn forms spherical micelles on the DNA backbone; which hinders their ability to pack. This is demonstrated by modelling the DNA along the hbb histone-like protein, showing that in the presence of CTA-4OHcinn, DNA does not pack properly around hbb. The abilities of CTA-4OHcinn to cause cell death through membrane disruption and to disperse a mature, multi-species biofilm are also confirmed experimentally.

Purpose: According to the revised Task Group number 43 recommendations, a brachytherapy source must be validated against a similar or identical source before its clinical application. The purpose of this investigation is to verify the dosimetric data of the high dose rate (HDR) BEBIG 192Ir source (Ir2.A85-2). Materials and Methods: The HDR 192Ir encapsulated seed was simulated and its main dosimetric data were calculated using Geant4 Application for Tomographic Emission (GATE) simulation code. Cubic cells were used for the calculation of dose rate constant and radial dose function while for anisotropy function ring cells were used. DoseActors were simulated and attached to the respective cells to obtain the required data. Results: The dose rate constant was obtained as 1.098 ± 0.003 cGy.h − 1.U − 1, differing by 1.0% from the reference value reported by Granero et al. Similarly, the calculated values for radial dose and anisotropy functions presented good agreement with the results obtained by Granero et al. Conclusion: The results of this study suggest that the GATE Monte Carlo code is a valid toolkit for benchmarking brachytherapy sources and can be used for brachytherapy simulation-based studies and verification of brachytherapy treatment planning systems.

Background: Gastro-esophageal (GE) junction cancer is the fastest-growing tumor, particularly in the United States (US). Objective: This study aimed to compare dosimetric and radiobiological factors among field-in-field (FIF), three-field (3F), and four-field box (4FB) radiotherapy planning techniques for gastro-esophageal junction cancer.Material and Methods: In this experimental study, thirty patients with GE junction cancer were evaluated, and three planning techniques (field-in-field (FIF), three-field (3F), and four-field box (4FB)) were performed for each patient for a 6-MV photon beam. Dose distribution in the target volume, the monitor units (MUs) required, and the dose delivered to organs at risk (OARs) were compared for these techniques using the paired-sample t-test. Results: A significant difference was measured between the FIF and 3F techniques with respect to conformity index (CI), dose homogeneity index (HI), and tumor control probability (TCP) for the target organ, as well as the Dmean for the heart, kidneys, and liver. For the spinal cord, the FIF technique showed a slight reduction in the maximum dose compared to the other two techniques. In addition, the V20 Gy of the lungs and the normal tissue complication probability (NTCP) of all OARs were reduced with FIF method. Conclusion: The FIF technique showed better performance for treating patients with gastro-esophageal junction tumors, in terms of dose homogeneity in the target, conformity of the radiation field with the target volume, TCP, less dose to healthy organs, and fewer MU.

An increase in the consumption of food fish, combined with a decrease in the harvest of fish, is driving the aquaculture industry at a fast pace. In parallel with the growth in the aquaculture sector and resulting stresses, the prevalence of diseases in farmed fish can increase. Although effective administration and prophylaxis are the main factors safeguarding fish species against diseases, recent approaches to mitigate the response caused by typical stressors include the uses of dietary additives. Microalgae are one of the main sources of nutrients, namely protein, lipids, vitamins, minerals, and pigments in aquatic animal diets. Numerous studies have proved the beneficial effects of microalgae on fish growth performance, feed utilization, disease resistance, and immunological and antioxidant activities. On the other hand, the administration of different microalgae to fish feed can enhance the fillet quality from several aspects, leading to an overall improvement in fillet shelf-life. This review focuses on the evidence supporting the beneficial effects of various microalgae on biochemical and organoleptic aspects as well as the proximate composition of carcasses in fish species.

Abstract In this work, we study ultra-low energy implantation into MoS2 monolayers to evaluate the potential of the technique in two-dimensional materials technology. We use 80Se+ ions at the energy of 20 eV and with fluences up to 5.0·1014 cm−2. Raman spectra of the implanted films show that the implanted ions are predominantly incorporated at the sulfur sites and MoS2−2x Se2x alloys are formed, indicating high ion retention rates, in agreement with the predictions of molecular dynamics simulations of Se ion irradiation on MoS2 monolayers. We found that the ion retention rate is improved when implantation is performed at an elevated temperature of the target monolayers. Photoluminescence spectra reveal the presence of defects, which are mostly removed by post-implantation annealing at 200 °C, suggesting that, in addition to the Se atoms in the substitutional positions, weakly bound Se adatoms are the most common defects introduced by implantation at this ion energy.

Abstract Background Covering the prepared sterile back tables (PSBTs) during periods of nonuse and during active surgeries may decrease contamination of sterile surgical instruments that have direct contact to surgical wound. The Association of periOperative Registered Nurses (AORN) declared that an easy method for covering and removing the drape will ultimately be most effective (e.g. standard two-drape method). Hence, this study was designed to test the hypothesis that using a novel single-drape cover had more efficiency and safety in decreasing airborne bacteria-carrying particles (ABCPs) settling on the PSBTs during static and dynamic periods than the standard two-drape method. Methods This experimental study was conducted with using 918 agar plates to detect contamination of the PSBTs with ABCPs on two conditions (static and dynamic) at an academic medical center in Kashan, Iran, from September 25, 2021, to January 20, 2022. The contamination of PSBTs was evaluated by 6 agar settle plates (n = 918 in total) on each PSBT in static and dynamic operating room (OR) conditions. At each time-point, this set-up was repeated on two occasions else during data collection, establishing 81 PSBTs in total. Tested groups included the PSBTs covered with the standard two-drape method, the novel single-drape cover, or no cover. The plates were collected after 15, 30, 45, 60, 120, 180, 240 min and 24 h. The primary outcome measured was comparison of mean bioburden of ABCPs settling on covered PSBTs on two conditions by using agar settle plates. The secondary outcomes measured were to determine the role of covering in decreasing contamination of PSBTs and the estimation of time-dependent surgical instrument contamination in the uncovered PSBTs on two conditions by using agar settle plates. Results Covering the PSBTs during static and dynamic OR conditions lead to a significantly decreased bioburden of ABCPs on them (P 0.05). Conclusions We found that there is no preference for using the novel single-drape cover than the standard two-drape method. Our results showed a significant decrease in bioburden of ABCPs on the PSBTs when those were covered during static and dynamic OR conditions, indicating the efficiency for covering the PSBTs during periods of nonuse and during active surgery.

Background: Skin is a sensitive organ and should be spared in radiotherapy and irradiation of skin in radiotherapy can cause to acute and late skin effects such as erythema, desquamation, epilation, color change, or even necrosis. Objective: The aim of the present study is to do skin dosimetry in radiotherapy of parotid cancer using Gafchromic EBT3 radiochromic film. EBT3 radiochromic films were calibrated in 0.2-5 Gy dose range.Material and Methods: This is an experimental study in the field of radiotherapy physics. Treatment planning was performed on a RANDO phantom for treatment of parotid cancer by a clinical oncologist. Based on the treatment planning, the skin dose at various points in the overlapping region of right anterior-oblique and right posterior-oblique fields were measured using EBT3 radiochromic film. Results: The minimum and maximum skin doses in a fraction (with 2.0 Gy prescribed dose) were 0.50 Gy and 0.97 Gy, respectively. Based on these values, the total skin dose in 30 treatment fractions (for removed tumor) or in 35 treatment fractions (for unremoved tumor) was in the range of 15-33 Gy. Conclusion: Based on the skin dosimetry results of parotid cancer radiotherapy using EBT3 films, it is predicted that there will occur mild skin reactions and these reactions can be neglected due to being mild.

Based on recent calculations of the self-diffusion (SD) coefficient in amorphous silicon (a-Si) by classical Molecular Dynamics simulation [Posselt et al., J. Appl. Phys. 131, 035102 (2022)], detailed investigations on atomic mechanisms are performed. For this purpose, two Stillinger–Weber-type potentials are used, one strongly overestimates the SD coefficient, while the other leads to values much closer to the experimental data. By taking into account the individual squared displacements (or diffusion lengths) of atoms, the diffusional and vibrational contributions to the total mean squared displacement can be determined separately. It is shown that the diffusional part is not directly correlated with the concentration of coordination defects. The time-dependent distribution of squared displacements of atoms indicates that in a-Si, a well-defined elemental diffusion length does not exist, in contrast to SD in the crystalline Si. The analysis of atoms with large squared displacements reveals that the mechanisms of SD in a-Si are characterized by complex rearrangements of bonds or exchanges of neighbors. These are mono- and bi-directional exchanges of neighbors and neighbor replacements. Exchanges or replacements may concern up to three neighbors and may occur in relatively short periods of some ps. Bi- or mono-directional exchange or replacement of one neighbor atom happens more frequently than processes including more neighbors. A comparison of results for the two interatomic potentials shows that an increased three-body parameter only slows down the migration but does not change the migration mechanisms fundamentally.

Lymphoid cells play a critical role in the immune system, which includes three subgroups of T, B, and NK cells. Recognition of the complexity of the human genetics transcriptome in lymphopoiesis has revolutionized our understanding of the regulatory potential of RNA in normal lymphopoiesis and lymphoid malignancies. Long non-coding RNAs (lncRNAs) are a class of RNA molecules greater than 200 nucleotides in length. LncRNAs have recently attracted much attention due to their critical roles in various biological processes, including gene regulation, chromatin organization, and cell cycle control. LncRNAs can also be used for cell differentiation and cell fate, as their expression patterns are often specific to particular cell types or developmental stages. Additionally, lncRNAs have been implicated in lymphoid differentiation, such as regulating T-cell and B-cell development, and their expression has been linked to immune-associated diseases such as leukemia and lymphoma. In addition, lncRNAs have been investigated as potential biomarkers for diagnosis, prognosis, and therapeutic response to disease management. In this review, we provide an overview of the current knowledge about the regulatory role of lncRNAs in physiopathology processes during normal lymphopoiesis and lymphoid leukemia.

Abstract Chemical biocides remain the most effective mitigation strategy against microbiologically influenced corrosion (MIC), one of the costliest and most pervasive forms of corrosion in industry. However, toxicity and environmental concerns associated with these compounds are encouraging the development of more environmentally friendly MIC inhibitors. In this study, we evaluated the antimicrobial effect of a novel, multi-functional organic corrosion inhibitor (OCI) compound, cetrimonium trans-4-hydroxy-cinnamate (CTA-4OHcinn). Attachment of three bacterial strains, Shewanella chilikensis, Pseudomonas balearica and Klebsiella pneumoniae was evaluated on wet-ground (120 grit finish) and pre-oxidised carbon steel surfaces (AISI 1030), in the presence and absence of the new OCI compound. Our study revealed that all strains preferentially attached to pre-oxidised surfaces as indicated by confocal laser scanning microscopy, scanning electron microscopy and standard colony forming unit (CFU) quantification assays. The inhibitor compound at 10 mM demonstrated 100% reduction in S. chilikensis attachment independent of initial surface condition, while the other two strains were reduced by at least 99.7% of the original viable cell number. Our results demonstrate that CTA-4OHcinn is biocidal active and has promise as a multifunctional, environmentally sound MIC inhibitor for industrial applications.

Background: Computed tomography (CT) is currently known as a versatile imaging tool in the clinic used for almost all types of cancers. The major issue of CT is the health risk, belonging to X-ray radiation exposure. Concerning this, Monte Carlo (MC) simulation is recognized as a key computational technique for estimating and optimizing radiation dose. CT simulation with MCNP/MCNPX MC code has an inherent problem due to the lack of a fan-beam shaped source model. This limitation increases the run time and highly decreases the number of photons passing the body or phantom. Recently, a beta version of MCNP code called MCNP-FBSM (Fan-Beam Source Model) has been developed to pave the simulation way of CT imaging procedure, removing the need of the collimator. This is a new code, which needs to be validated in all aspects. Objective: In this work, we aimed to develop and validate an efficient computational platform based on modified MCNP-FBSM for CT dosimetry purposes.Material and Methods: In this experimental study, a setup is carried out to measure CTDI100 in air and standard dosimetry phantoms. The accuracy of the developed MC CT simulator results has been widely benchmarked through comparison with our measured data, UK’s National Health Service’s reports (known as ImPACT), manufacturer’s data, and other published results. Results: The minimum and maximum observed mean differences of our simulation results and other above-mentioned data were the 1.5%, and 9.79%, respectively. Conclusion: The developed FBSM MC computational platform is a beneficial tool for CT dosimetry.

Background: Euronext Paris Advanced Orthopedic Solutions (EOS) system is a new radiography system, capable of obtaining two-dimensional and three-dimensional images from bony structures in the body. Objective: The aim of this study is to estimate equivalent dose and the risk of exposure induced cancer death (REID) in different organs of body due to EOS imaging system.Material and Methods: In this experimental study, totally 120 patients were evaluated for various imaging techniques of lower limb, full spine and whole body. Equivalent dose and REID for colon, liver, lung, stomach, breast, bladder, ovary, blood cells (leukemia) and other organs were calculated using PCXMC software (version 2.0.1.2) based on Monte Carlo simulation of X-ray and human phantoms. The data on imaging technique, including age, sex, kVp, dose area product (DAP), mA, focal to detector distance were introduced as the input of PCXMC. Results: The maximum equivalent dose (mSv) due to EOS imaging system, was estimated for the bladder 0.240±0.066 for the full body technique and 0.240±0.093 for the lower limb technique, respectively, in both males and females. The maximum organ REID (incidence per million) due to EOS imaging system was estimated for lungs as 2.59±1.0 and 2.53±0.9, for the full body technique in both males and females, respectively. Conclusion: Generally, the equivalent dose and REID by EOS imaging system in different organs of body is low due to the low radiation dose received by the body in different techniques and views.

Effective electrocatalyst is crucial in promoting CO2 reduction to address current energy/environmental issue. Here, the authors develop bimetallic layered two-dimensional conjugated metal-organic framework to synergistically and efficiently electro-catalyze CO2 to CO toward syngas synthesis.

Purpose: This study aims to validate the dosimetric characteristics of High Dose Rate (HDR) 60Co source (Co0.A86 model) using GATE Geant4-based Monte Carlo code. According to the recommendation of the American Association of Physicists in Medicine (AAPM) task group report number 43, the dosimetric parameters of a new brachytherapy source should be verified either experimentally or by Monte Carlo calculation before clinical applications. The validated 60Co source in this study will be used for the simulation of intensity-modulated brachytherapy (IMBT) of vaginal cancer using the same GATE Geant4-based Monte Carlo code in the future. Materials and methods: GATE (version 9.0) simulation code was used to model and calculate the required TG-43U1 dosimetric data of the 60Co HDR source. DoseActors were defined for calculation of dose rate constant, radial dose function, and anisotropy function in a water phantom with an 80 cm radius. Results: The dose rate constant was obtained as 1.070±0.008cGy.h−1.U−1 which shows a relative difference of 2.01% compared to the consensus value, 1.092 ​cGy.h−1.U−1. The calculated results of anisotropy and radial dose functions starting from 0.1 cm to 10 cm around the source showed excellent agreement with the results of published studies. The mean variation of the radial dose and anisotropy functions values from the consensus data were 1% and 0.9% respectively. Conclusion: Findings from this investigation revealed that the validation of the HDR 60Co source is feasible by the GATE Geant4-based Monte Carlo code. As a result, the GATE Monte Carlo code can be used for the verification of the brachytherapy treatment planning system.

Abstract Background Methanol is highly toxic to human beings and naturally exists in some beverages. Having access to an easy and cheap method for its determination is of great importance to increase the safety of use of these beverages. Our main aim is to evaluate methanol concentration of some alcoholic beverages in Iran black market and compare it with the European and US standards. Also, we evaluated the efficacy of a newly designed and produced chemical kit in determining the risk of methanol toxicity by drinking of such samples compared to gas chromatography method. Methods Methanol content of suspected alcoholic beverages referred to forensic toxicology laboratory, Guilan province, Iran was measured using gas chromatography and a recently designed kit based on modified colorimetric chromotropic acid method. Results Of 1221 samples, 145 (11.9%) had no ethanol content, while in three samples (0.25%), methanol was high enough (700,000; 870,000; 920,000 mg/L) to cause severe methanol toxicity. Median [IQR] ethanol content of the suspected samples was 9% [3.7, 32.75]. Methanol was detected in 128 (10.48%) samples using gas chromatography method and 160 samples (13.1%) with designed kit with 100% sensitivity, 97.07% specificity, and 100% negative-predictive-value. Conclusions Alcoholic beverages produced in local black market in Iran are not safe at all. The application of the new method is practical, rapid, easy, and accurate to evaluate the risk of methanol toxicity in suspected alcoholic drinks.

Designing core/shell nanowires with desired optoelectronic properties of III-V semiconductor alloys remains a challenge. Here, the authors report an engineering strategy to surmount strain-induced difficulties in the growth achieving highly strained cores with a sizeable change in their band gap.

Objective(s): The purpose of this research is to study the effect of beta spectrum on absorbed fraction ( ) and to find suitable analytical functions for beta spectrum absorbed fractions in spherical and ellipsoidal volumes with a uniform distribution for several radionuclides that are commonly used in nuclear medicine.Methods: In order to obtain the beta particle absorbed fraction, Monte Carlo simulations were performed by using the MCNPX code. The validation of the simulations was performed by calculating the absorbed fractions in spheres and comparing the results with the data published by other investigators. The absorbed fractions were calculated and compared by using an actual beta energy spectrum with those obtained through the mean beta energy of 14C, 199Au, 177Lu, 131I, 90Sr, 153Sm, 186Re, 32P, 90Y, 38Cl and 88Rb radionuclides.Results: The maximum difference between the absorbed fractions for beta particles accounting for the whole beta spectrum of all the considered nuclides was 29.62% with respect to the mean beta energy case. Suitable analytical relationships were found between the absorbed fraction and the generalized radius, and the dependence of the fitting parameters from beta spectrum energy was discussed and fitted by appropriate parametric functions.Conclusion: The results allowed the calculation of the absorbed fractions from the above stated beta sources uniformly distributed in spherical and ellipsoidal volumes of any ellipticity and volume, in a wide range of practical volumes that are not only used for internal dosimetry in nuclear medicine applications, but also in radiological protection estimates ofdoses from internal contamination.

Purpose: In this research, we aimed to identify the pattern of cooperative relations among the Pistachio producers in Damankuh rural district in Damghan. The social capital among the producers was also evaluated. Design/methodology/approach: In this paper, the cooperative relations and the social capital among the Pistachio producers in Mehmandoost, Zarrinabad and Hoseinabad Doolab, which are located in Damankooh in Damghan, were studied by applying social network analysis method. Thus, 66 people from Mehmandoost, 70 producers from Zarrinabad, and 74 farmers from Hosseinabad Dulab were studied. The relations which were studied included cooperation in exchanging farming tools, irrigation of Pistachio orchards, marketing and pest control. For analyzing these relations, we used network- level indicators of social network analysis including density, centralization, reciprocity, transitivity and Geodesic distance. These indicators were analyzed in the UCINET software. Finding: Results showed that the network macro-level indicators including density, centralization, reciprocity, transitivity and geodesic distance in studied villages were very low. This has caused problems for producers to cooperate with each other and threatens the stability of producers’ network and indicates cooperation among pistachio producers requires tremendous investment of both time and cost. Research limitations/implications: Problems like accessing farmers, distributing questionnaires among them and the long time needed in order to interview them were among the challenges faced in this research. Practical implications‌: In order to increase cooperation among the producers and social capital in their network it is suggested that farmers be instructed and informed by holding cooperative workshops, handling their problems in irrigation and pest control, running local cooperatives for supporting the farmers in the crop prices and paying attention to their demands. Originality/value: Given the importance of the studied area in the production of Pistachio, paying attention to cooperation and social capital among producers, can be a big step in using the fertility (potentiality) of this region to develop and improve the Pistachio production.

In radiotherapy of head and neck cancer, the presence of high density materials modifies photon dose distribution near these high density materials during treatment. The aim of this study is to calculate the backscatter and attenuation effects of a healthy tooth, Amalgam, Ni-Cr alloy and Ceramco on the normal tissues before and after these materials irradiated by 6 and 15 MV photon beams, respectively. All measurements were carried out in a water phantom with dimension of 50 × 50 × 50 cm3with an ionization chamber detector. Two points before and four points after the dental sample were considered to score the photon dose. The depth dose on the central beam axis was explored in a water phantom for source to surface distance (SSD) of 100 cm in a 10 × 10 cm2 field size. The percentage dose change was obtained relative to the dose in water versus depth of water, tooth, Amalgam, Ni-Cr alloy and Ceramco for the photon beams. The absolute dose (cGy) was measured by prescription of 100 cGy dose in the water phantom at depth of 2.0 and 3.1 cm for 6 and 15 MV photons, respectively. At depth of 0.6 cm, the maximum percentage dose increase was observed with values of 6.99% and 9.43%for Ni-Cr and lowest percentage dose increase of 1.49% and 2.63% are related to the healthy tooth in 6 and 15 MV photon beams, respectively. The maximum absolute dose of 95.58 cGy and 93.64 cGy were observed at depth of 0.6 cm in presence of Ni-Cr alloy for 6 and 15 MV photon beams, respectively. The presence of dental restorations can cause backscattering dose during head and neck radiation therapy. Introduction of compositions and electron density of high density materials can improve the accuracy of dosimetric calculations in treatment planning systems to deliver the relevant dose to target organ and reduce the backscattering dose in healthy tissues in the surrounding of tooth.

Controlled production of defects in hexagonal boron nitride (h-BN) through ion irradiation has recently been demonstrated to be an effective tool for adding new functionalities to this material, such as single-photon generation, and for developing optical quantum applications. Using analytical potential molecular dynamics, we study the mechanisms of vacancy creation in single- and multi-layer h-BN under low- and high-fluence ion irradiation. Our results quantify the densities of defects produced by noble gas ions in a wide range of ion energies and elucidate the types and distribution of defects in the target. The simulation data can directly be used to guide the experiment aimed at the creation of defects of particular types in h-BN targets for single-photon emission, spin-selective optical transitions and other applications by using beams of energetic ions.

Aim of the study : The 57 Co radioisotope has recently been proposed as a hypothetical brachytherapy source due to its high specific activity, appropriate half-life (272 days) and medium energy photons (114.17 keV on average). In this study, Task Group No. 43 dosimetric parameters were calculated and reported for a hypothetical 57 Co source. Material and methods : A hypothetical 57 Co source was simulated in MCNPX, consisting of an active cylinder with 3.5 mm length and 0.6 mm radius encapsulated in a stainless steel capsule. Three photon energies were utilized (136 keV [10.68%], 122 keV [85.60%], 14 keV [9.16%]) for the 57 Co source. Air kerma strength, dose rate constant, radial dose function, anisotropy function, and isodose curves for the source were calculated and compared to the corresponding data for a 192 Ir source. Results : The results are presented as tables and figures. Air kerma strength per 1 mCi activity for the 57 Co source was 0.46 cGyh–1 cm 2 mCi–1. The dose rate constant for the 57 Co source was determined to be 1.215 cGyh–1U–1. The radial dose function for the 57 Co source has an increasing trend due to multiple scattering of low energy photons. The anisotropy function for the 57 Co source at various distances from the source is more isotropic than the 192 Ir source. Conclusions : The 57 Co source has advantages over 192 Ir due to its lower energy photons, longer half-life, higher dose rate constant and more isotropic anisotropic function. However, the 192 Ir source has a higher initial air kerma strength and more uniform radial dose function. These properties make 57 Co a suitable source for use in brachytherapy applications.

Natural resources general organization of Mazandaran Province on the strength of rehabilitation & transfer law (approved in 1980 and its executive regulations due to 31 & 32 issues) have transferred national lands to some persons and legal sectors in order to unemployment, poverty and Natural resources degradation reduction and also socio-economic condition improvement by industrial and agricultural activities in rural communities. Now, after 3 decades of approval and execution of transfer process, we decided to analyze socio-economic effects and its success level in Mazandaran Province. Among the statistical society in present study including 586 transferred cases from 1993 to 2013, 169 samples were randomly selected by Morgan table and these cases were interviewed directly. Our considered variables include: (a) Natural resources area (b) employment level (c) success & efficiency factors. After collecting and arrangement of field data by questionnaires and analyses them by SPSS18 software, the founding were presented as charts and tables by Chi-square method. The results have show that 4709 hectares of national lands have transferred up to now and 56% of this process were allocated to agricultural activities and we finally found that the execution of transfer process have no worthy influence to its targets.

Aim of the study: Accurate skin dose assessment is necessary during breast radiotherapy to assure that the skin dose is below the tolerance level and is sufficient to prevent tumour recurrence. The aim of the current study is to measure the skin dose and to evaluate the geometrical/anatomical parameters that affect it. Material and methods : Forty patients were simulated by TIGRT treatment planning system and treated with two tangential fields of 6 MV photon beam. Wedge filters were used to homogenise dose distribution for 11 patients. Skin dose was measured by thermoluminescent dosimeters (TLD-100) and the effects of beam incident angle, thickness of irradiated region, and beam entry separation on the skin dose were analysed. Results : Average skin dose in treatment course of 50 Gy to the clinical target volume (CTV) was 36.65 Gy. The corresponding dose values for patients who were treated with and without wedge filter were 35.65 and 37.20 Gy, respectively. It was determined that the beam angle affected the average skin dose while the thickness of the irradiated region and the beam entry separation did not affect dose. Since the skin dose measured in this study was lower than the amount required to prevent tumour recurrence, application of bolus material in part of the treatment course is suggested for post-mastectomy advanced breast radiotherapy. It is more important when wedge filters are applied to homogenize dose distribution.

Purpose: Low energy sources are routinely used in prostate brachytherapy. 125 I is one of the most commonly used sources. Low energy 131 Cs source was introduced recently as a brachytherapy source. The aim of this study is to compare dose distributions of 125 I, 103 Pd, and 131 Cs sources in interstitial brachytherapy of prostate. Material and methods: ProstaSeed 125 I brachytherapy source was simulated using MCNPX Monte Carlo code. Additionally, two hypothetical sources of 103 Pd and 131 Cs were simulated with the same geometry as the ProstaSeed 125 I source, while having their specific emitted gamma spectra. These brachytherapy sources were simulated with distribution of forty-eight seeds in a phantom including prostate. The prostate was considered as a sphere with radius of 1.5 cm. Absolute and relative dose rates were obtained in various distances from the source along the transverse and longitudinal axes inside and outside the tumor. Furthermore, isodose curves were plotted around the sources. Results : Analyzing the initial dose profiles for various sources indicated that with the same time duration and air kerma strength, 131 Cs delivers higher dose to tumor. However, relative dose rate inside the tumor is higher and outside the tumor is lower for the 103 Pd source. Conclusions : The higher initial absolute dose in cGy/(h.U) of 131 Cs brachytherapy source is an advantage of this source over the others. The higher relative dose inside the tumor and lower relative dose outside the tumor for the 103 Pd source are advantages of this later brachytherapy source. Based on the total dose the 125 I source has advantage over the others due to its longer half-life.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Transition-metal dichalcogenide nanotubes (TMC-NTs) are investigated for their electromechanical properties under applied tensile strain using density functional-based methods. For small elongations, linear strain-stress relations according to Hooke’s law have been obtained, while for larger strains, plastic behavior is observed. Similar to their 2D counterparts, TMC-NTs show nearly a linear change of band gaps with applied strain. This change is, however, nearly diameter-independent in case of armchair forms. The semiconductor-metal transition occurs for much larger deformations compared to the layered tube equivalents. This transition is faster for heavier chalcogen elements, due to their smaller intrinsic band gaps. Unlike in the 2D forms, the top of valence and the bottom of conduction bands stay unchanged with strain, and the zigzag NTs are direct band gap materials until the semiconductor-metal transition. Meanwhile, the applied strain causes modification in band curvature, affecting the effective masses of electrons and holes. The quantum conductance of TMC-NTs starts to occur close to the Fermi level when tensile strain is applied.