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The present study was planned to understand the heavy metal burden and its possible actions in blood of occupational females working at brick kilns at Rawat, Pakistan. A total of 232 women were included in the study, of which 114 presented control subjects. Apart from collection of demographic data, fertility indicators and body mass index (BMI), blood was collected from subjects that was later used for the determination of heavy metal concentrations using atomic absorption spectroscopy and haematological profile. Blood was centrifuged and plasma was obtained and stored at - 20° to study biochemical variables (sodium dismutase, peroxidase, reactive oxygen species, thiobarbituric acid reactive species, protein estimation), lipid profile and cortisol concentrations among the two groups. Analysis of heavy metal in blood showed elevated levels of cadmium (3.09 ± 0.01 μg/dl), chromium (4.20 ± 0.02 μg/dl) and nickel (5.59 ± 0.03 μg/dl) in worker's group as compared with control. Increased platelet count; decreased antioxidant enzyme and increased oxidants level; increased total cholesterol, low-density lipoprotein (LDL) and triglyceride (TG); decreased total protein and high-density lipoprotein (HDL); and increased cortisol levels were evident among workers as compared with the control group. The study concluded that occupational workers experience increased heavy metals burden in blood and, therefore, pose a risk to human health by causing reduction in antioxidant enzymes concentration and increase in stress conditions.

This work reports the study of platinum silicide formation on reaction with an oxygen contaminated silicon layer. The observed results are potentially a novel approach to use silicide forming metals as a direct contact electrode to the crystalline core-amorphous silicon oxide shell structure of silicon nanowires without the need of hazardous acids, e.g. hydrofluoric acid, which is commonly used during lithography device preparation to remove the oxide shell. The simulation of the in-situ RBS spectra at temperatures above 250 °C showed the reaction of platinum with the oxygen contaminated silicon layer, forming a new layer with a stoichiometry corresponding to the silicide phase containing about 10–15 at.% oxygen (e.g. Pt0.55, Si0.3, O0.15). The presence of oxygen is attributed to the diffusion of its atoms through the silicide layer to the surface. The in-situ XPS data revealed the diffusion of oxygen towards the surface during the reaction of platinum and silicon while in-situ XRD results showed the sequential formation of the Pt2Si and PtSi phases. Therefore, these results present a simple and user-friendly approach applicable in the fabrication of contact structures in the core-shell silicon nanowire based devices.

This study aimed to assess the potential of a multidimensional approach to differentiate body hairs based on their physico-chemical properties and whether body hairs can replace the use of scalp hair in studies linked to forensic and systemic intoxication. This is the first case report controlling for confounding variables to explore the utility of multidimensional profiling of body hair using synchrotron synchrotron microbeam X-ray fluorescence (SR-XRF) for longitudinal and hair morphological region mapping) and benchtop methods, including attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) (complemented with chemometrics analysis), energy dispersive X-ray analysis (EDX) (complemented with heatmap analysis), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) analysis (complemented by descriptive statistics) to profile different body hairs in terms of their elemental, biochemical, thermal, and cuticle properties. This multidimensional approach provided supportive information to emphasize the intricate and rather complex interplay between the organization and levels of elements and biomolecules within the crystalline and amorphous matrix of different body hairs responsible for the differences in physico-chemical properties between body hairs that are predominantly affected by the growth rate, follicle or apocrine gland activity, and external factors such as cosmetic use and exposure to environmental xenobiotics. The data from this study may have important implications for forensic science, toxicology and systemic intoxication, or other studies involving hair as a research matrix.

Scientific collaborations among nations to address common problems and to build international partnerships as part of science diplomacy is a well-established notion. The international flow of people and ideas has played an important role in the advancement of the 'Sciences' and the current pandemic scenario has drawn attention towards the genuine need for a stronger role of science diplomacy, science advice and science communication. In dealing with the COVID-19 pandemic, visible interactions across science, policy, science communication to the public and diplomacy worldwide have promptly emerged. These interactions have benefited primarily the disciplines of knowledge that are directly informing the pandemic response, while other scientific fields have been relegated. The effects of the COVID-19 pandemic on scientists of all disciplines and from all world regions are discussed here, with a focus on early-career researchers (ECRs), as a vulnerable population in the research system. Young academies and ECR-driven organisations could suggest ECR-powered solutions and actions that could have the potential to mitigate these effects on ECRs working on disciplines not related to the pandemic response. In relation with governments and other scientific organisations, they can have an impact on strengthening and creating fairer scientific systems for ECRs at the national, regional, and global level.

Pd(50 nm)/Ti(25 nm)/Pd(50 nm) multilayer stack has been deposited on Ti and Ti6Al4V substrates; we have studied the intermixing of layers upon annealing at the hydrogenation temperature of 550 °C, under vacuum, H/Ar gas mixture and pure hydrogen atmospheres. Scanning electron microscopy (SEM) micrographs indicated surface roughening in samples annealed under vacuum and H/Ar gas mixture while those annealed under pure H2 remained relatively smoother. Rutherford backscattering spectrometry (RBS) revealed intermixing of layers as evidenced by the diffusion of Pd toward the bulk, while XRD indicated the formation of PdTi2 phase in the samples annealed under vacuum and H/Ar gas mixture atmosphere. In-situ, real-time RBS showed that the annealing under pure H2 preserves the integrity of the Pd catalyst. No indication of the PdTi2 formation in the pure H2 annealed samples was observed; instead only the TiH2 phase appeared, indicating the absorption of H into the system.

In the present study, possible differences in the mineral composition of transgenic versus non-transgenic sorghum grains were investigated using inductively coupled atomic emission spectroscopy (ICP-AES); and, in-tissue elemental mapping by micro Proton-Induced X-ray Emission (micro-PIXE) analysis. ICP AES was used to analyse the bulk mineral content of the wholegrain flour derived from each genotype; whilst micro-PIXE was used to interrogate localised differences in mineral composition specific to certain areas of the grain, such as the bran layer and the central endosperm tissue. According to the results obtained, no significant difference in the average Fe, Zn or Ca content was found to differentiate the transgenic from the wild-type grain using ICP-AES. However, using micro-PIXE, a significant reduction in zinc could be detected in the bran layer of the transgenic grains relative to wild-type. Although it is difficult to draw firm conclusions, as a result of the small sample size used in this study, micro-PIXE has nonetheless proven itself as a useful technique for highlighting the possibility that there may be reduced levels of zinc accumulation in the bran layer of the transgenic grains. Given that the genetic modification targets proteins that are highly concentrated in certain parts of the bran tissue, it seems plausible that the reduced levels of zinc may be an unintended consequence of the silencing of kafirin proteins. Although no immediate health or nutritional concerns emerge from this preliminary finding, it is noted that zinc plays an important biological role within this part of the grain as a structural stabiliser and antioxidant factor. Further study is therefore needed to assess more definitively the extent of the apparent localised reduction in zinc in the transgenic grains and how this may affect other important grain quality characteristics.

In this exploratory study, the application of secondary ion mass spectrometry with a heavy primary ion beam with an energy of several MeVs (MeV-SIMS) is presented for the simultaneous detection and spatial distribution mapping of lithium in a single, chemically unprocessed strand of scalp hair across a longitudinal profile.

Graphical abstract, Highlights • Soil-plant physico-chemical properties may determine regional elemental profiles. • Pore interconnectivity and distribution varied between regional beans. • Multidimensional data promising for advising coffee qualitative characteristics., The physico-elemental profiles of commercially attained and roasted organic coffee beans from Ethiopia, Colombia, Honduras, and Mexico were compared using light microscopy, X-ray micro-computed tomography, and external beam particle induced X-ray emission. External beam PIXE analysis detected P, S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, Br, Rb, and Sr in samples. Linear discriminant analysis showed that there was no strong association between elemental data and production region, whilst a heatmap combined with hierarchical clustering showed that soil-plant physico-chemical properties may influence regional elemental signatures. Physical trait data showed that Mexican coffee beans weighed significantly more than beans from other regions, whilst Honduras beans had the highest width. X-ray micro-computed tomography qualitative data showed heterogeneous microstructural features within and between beans representing different regions. In conclusion, such multi-dimensional analysis may present a promising tool in assessing the nutritional content and qualitative characteristics of food products such as coffee.

Scat hair presents a diverse profile of hairs for morphological assessment that may find versatile applications in wildlife forensic investigations. Successful morphological assessment of scat hair microstructure, however, depends on a robust sectioning methodology. We assessed the feasibility and efficacy of a cryosectioning technique compared to that of a gold standard hand-sectioning technique. Scat hairs were embedded in paraffin wax and hand-sectioned, while cryopreserved scat hairs were sectioned with a cryostat. The results showed that cryosectioning preserved the pristine morphology of the scat hair and provided cross sections more amenable to high-resolution imaging of hair internal microstructure than hand-sectioning. The cryosectioning technique may find novel applications as a more reliable and robust technique to aid (i) scat hair internal microstructure analysis for cross-referencing with species identification keys in wildlife forensic studies and (ii) downstream toxicological analysis in wildlife forensic studies as hair biochemistry is not altered during cryopreservation.

Multi-element profiling is essential in understanding the metal-tolerant behavior of metallophytes. Although previous reports using multi-elemental analyses show that the metallophytes Blepharis aspera , Blepharis diversispina (Acanthaceae) and Helichrysum candolleanum (Asteraceae) take up metals, no information exists on elemental spatial distribution and concentrations in specific tissues of these plants. The aim of this study therefore was to assess the spatial distribution and concentration of copper, nickel and other elements in leaf tissues of these plants using micro-PIXE. Whole plants were collected with soil in pots from an operational copper and nickel mine (i.e., a copper and nickel mineralized area), Selkirk, about 40 km north-east of Francistown, Botswana. On the same day the samples were transported by air to iThemba LABS in South Africa. Leaf specimens were cryofixed in liquid propane cooled by LN2. Parallel samples were embedded in resin for anatomical studies to facilitate interpretation of elemental maps. The distribution and concentration of copper, nickel, and other elements in leaf tissues were determined using micro-PIXE and proton backscattering spectrometry. Data evaluation was performed using GeoPIXE II software. Micro-PIXE showed that H. candolleanum had the highest whole leaf content of copper (70 ± 3 μg g −1 DW) and nickel (168 ± 5 μg g −1 DW), followed by B. aspera (Cu: 25 ± 1 μg g −1 DW; Ni: 166 ± 4 μg g −1 DW) and B. diversispina (Cu: 3 ± 1 μg g −1 DW; Ni, below detection limit). For specific leaf tissues, the highest levels of copper were found in the vascular bundle for H. candolleanum (167 ± 7 μg g −1 DW) and the lower epidermis for B. aspera (70 ± 9 μg g −1 DW). The highest levels of nickel were present in the vascular bundle of B. aspera (479 ± 10 μg g −1 DW) and H. candolleanum (90 ± 5 μg g −1 DW). Elemental maps showed a similar distribution pattern for copper and nickel in B. aspera and B diversispina , with these elements concentrated in the upper and lower epidermal regions. However, for H. candolleanum , both copper and nickel were concentrated in the mesophyll. The difference in concentration and accumulation patterns between B. aspera , B. diversispina and H. candolleanum suggests that the metal-tolerant adaptation of these metallophytes may differ.

Cutaneous fungi are known to affect parts of the outermost skin layers of mammals, including the epidermis, stratum spinosum and stratum corneum, as well as mucocutaneous membranes, genitalia or external ears. Relatively little is known about fungal infections of Mysticete cetaceans and studies are needed to determine the fungal diversity associated with these marine mammals. This case report was aimed at identifying the fungi associated with the skin of a diseased neonatal southern right whale (Eubalaena australis) found stranded in the Western Cape Province of South Africa. Initial physical examination on site revealed hyperplasia of the follicular and epidermal epithelium. Preliminary examination of skin biopsies using scanning electron microscopy indicated that the skin was colonized by fungal hyphae. Isolation methods yielded a number of fungal isolates, which were identified using standard morphology and rDNA sequence data. These analyses confirmed colonization of the cutaneous layers by sp...

Nothing is known about the effect of soil yeasts on the photosynthetic resource-use and carbon dynamics of plants. Here, we determined the effect of a plant growth-promoting isolate of Cryptococcus laurentii on the photosynthetic water and nutrient-use efficiencies, as well as the carbon economy of a Mediterranean sclerophyll, Agathosma betulina, grown under axenic conditions. The data showed that the higher photosynthetic water-use efficiency in yeast-inoculated plants was a consequence of higher maximum rates of CO2 assimilation, which was not related to foliar N and P content. We propose that photosynthetic stimulation in yeast-inoculated plants was a result of the increased demand for photosynthates of the yeast-root symbiosis.

The role of rhizosphere yeasts as plant nutrient-scavenging microsymbionts in resource-limited Mediterranean-type heathlands is unknown. This study, therefore, focused on quantitative elemental distribution within the roots of a medicinal sclerophyll, Agathosma betulina (Berg.) Pillans, grown under nutrient-poor conditions, and colonized by Cryptococcus laurentii. Micro-particle-induced X-ray emission (PIXE) was used to assess quantitative elemental distribution within the roots of A. betulina inoculated with viable C. laurentii, as well as within roots of control plants that received autoclaved yeast. To aid in the interpretation of heterogeneous elemental distribution patterns, apoplastic barriers (Casparian bands) in root tissues were located using fluorescence microscopy. In addition, root cross-sections were examined for endophytic C. laurentii using light and transmission electron microscopy (TEM). The average concentrations of P, Fe and Mn were significantly (P < 0.05) higher in roots of yeast-inoculated plants, compared to control plants. Casparian bands were observed in the exodermal cells of both treatments, and the presence of these bands was correlated with elemental enrichment in the epi/exodermal-outer cortical tissues. Light and TEM micrographs revealed that the yeast was not a root endophyte. This is the first report describing the role of a soil yeast as a plant nutrient-scavenging microsymbiont.

The interaction between a common soil yeast, Cryptococcus laurentii, and a slow-growing medicinal plant adapted to low-nutrient soils, Agathosma betulina (Berg.) Pillans, was studied. C. laurentii CAB 578 was isolated from the rhizosphere of wild A. betulina, and liquid chromatography-tandem mass spectrometry (LC-MS-MS) analysis revealed that the yeast was capable of producing polyamines, such as cadaverine and spermine, while growing in vitro in a chemically defined medium. Since the exogenous application of polyamines are known to impact on root growth, these findings supported the results obtained when axenic cultures of A. betulina seedlings were inoculated with C. laurentii CAB 578 and cultivated for 5 months under glasshouse conditions. The presence of the yeast increased root growth by 51%. Using soil dilution plates, it was demonstrated that yeast numbers were greater in the vicinity of the roots than in the bulk soil. In addition, fluoromicroscopy, in combination with the fluorescent probes Fungolight and Calcofluor white, revealed the presence of metabolic active yeast colonies on the rhizoplane 5 months after initiation of the experimentation. The study provided evidence for a symbiosis between C. laurentii and A. betulina.

Relatively little is currently known about the seedling physiology of arbuscular mycorrhizal (AM) Agathosma betulina, a sclerophyllous crop plant cultivated for its high-value essential oils and food additives. In addition, virtually nothing is known about the AM associations of this plant. Consequently, the effect of an indigenous community of AM fungi on P nutrition and C economy in seedlings, grown in nursery conditions, was determined during different stages of host and AM fungal establishment. AM fungal ribosomal gene sequence analyses were used to identify some of the fungi within the roots, responsible for the nutritional changes. During the early stages of host and AM fungal establishment (0 to 77 days after germination), host growth was reduced, whereas the rate of P-uptake and growth respiration was increased. Beyond 77 days of growth, the rate of P-uptake and growth respiration declined. These findings, together with results obtained after molecular analyses of root associated fungal DNA, indicate that AM fungi belonging to the genera Acaulospora and Glomus, improve P-uptake and costs of utilization during the early stages of seedling establishment in a nutrient-poor soil.

Background Facial affect recognition (FAR) abilities underpin emotional intelligence (EI). The latter is suggested to predict academic success and to be important for clinician-patient interaction. It is therefore of interest to investigate the possible association between FAR and academic performance in undergraduate medical students. Methods We assessed the association between the ability to recognize emotions through facial expression and exit examination performance, a measure of clinical proficiency, in undergraduate medical students stratified by gender at a South African tertiary institution using a prospective descriptive design. Data on the perception of facial expressions and exit examination marks were obtained from 144 (61%) females and 93 (39%) males with a mean age of 24.1 ± 1.6 years. Facial affect recognition measures on the Hexagon and Animation tasks were individually correlated with academic performance indicators using Pearson correlation. Results The perceptual discrimination of anger was associated with improved performance in anaesthetics (r = .24; p = .004) and urology (r = .24; p = .001), while the recognition of happiness was associated with decreased performance in obstetrics (r = −.21, p = .002). Gender was an effect modifier in the relationship between perceptual discrimination of anger and urology performance (p = .03), with a strong positive relationship for males, but a non-significant relationship for females. Conclusion There was no overall correlation between FAR and overall academic performance or with gender. However, subject (specialty) specific findings with recognition of specific emotions and with gender as effect modifier poses interesting questions about EI and FAR and prompts further research into FAR as a useful tool. Being an objective test and offering a more focused assessment makes FAR worthy of further application.

Background Emergency healthcare workers, including trainees and individuals in related occupations are at heightened risk of developing posttraumatic stress disorder (PTSD) and depression owing to work-related stressors. We aimed to investigate the type, frequency, and severity of direct trauma exposure, posttraumatic stress symptoms and other psychopathology amongst paramedic trainees. In order to create a risk profile for individuals who are at higher occupational risk of developing PTSD, we examined risk and resilience factors that possibly contributed to the presence and severity of posttraumatic symptomatology. Methods Paramedic trainees (n = 131) were recruited from a local university. A logistic regression analysis was conducted using the explanatory variables age, gender, population group, trauma exposure, depression, alcohol abuse, alcohol dependence, resilience and social support. Results 94% of paramedic trainees had directly experienced trauma, with 16% meeting PTSD criteria. A high rate of depression (28%), alcohol abuse (23%) and chronic perceived stress (7%) and low levels of social support was found. The number of previous trauma exposures, depression, resilience and social support significantly predicted PTSD status and depression had a mediating effect. Conclusion There is a need for efficient, ongoing screening of depressive and PTSD symptomatology in trauma exposed high risk groups so that early psychological supportive interventions can be offered.

Here, we assessed for the first time the frequency of religious delusions and the effect of treatment on religiosity and the phenomena of religious delusions in a Xhosa schizophrenia population. Religious delusions were present in 42 (70 %) participants, and treatment significantly reduced religiosity (p = 0.02) as well as mean scores for certain phenomena associated with the delusions including changes in both thinking (p = 0.0001) and behaviour (p = 0.0001), as well as affective response to the delusion (p = 0.0001) The high frequency of religious delusions may indicate a higher tolerance for religious delusions in this community. It is therefore important to educate spiritual leaders on mental illness.

We determined the frequency and correlates of current common mental disorders (CMDs) in a consecutive series of 649 adult patients with human immunodeficiency virus (HIV), tuberculosis (TB) or both receiving treatment at 16 primary health care centres across Zambia. Data on socio-demographic variables, clinical disease features, anxiety and mood disorders were collected. The frequency of any anxiety disorder (AD) was 30.8% and major depressive disorder (MDD) 11.3%. Although differences by disease group did not reach statistical significance, rates of suicidality (34.8%) and panic disorder (4.1%) were highest for the TB-HIV group (n = 269), while rates of generalised AD (13.3%), obsessive compulsive disorder (7.6%), posttraumatic stress disorder (7.4%) and any AD (37.8%) were highest for the HIV group (n = 149). Female gender (p = 0.004) predicted any current AD as well as current suicidality (p = 0.009), while lower education status (p0.001) predicted current MDD. World Health Organisation (WHO) clinical staging and antiretroviral treatment status were not significantly associated with MDD or anxiety in the HIV and co-infected groups. This study indicates the importance of early identification of CMDs in TB, HIV and co-infected patients, especially women and uneducated patients, newly initiated on treatment in primary care settings.

Objective: The use of thyroid tests to assess psychiatric patients remains debatable. Therefore, this study was conducted to examine the utility and cost effectiveness of the current protocol used in thyroid testing in adult psychiatric patients presenting at Stikland Hospital, Cape Town, South Africa. Method: This was a retrospective chart review conducted at Stikland Hospital between 1 January 2000 and 31 December 2005. The following data was recorded: demographic variables, clinical diagnoses at admission and discharge, number of days from admission to a thyroid test request, the reason for thyroid screening, number of thyroid tests, their yield and costs involved, as well as the action taken following an abnormal thyroid test result. Results: The mean age of patients (n = 1080: n = 364 male, n = 716 female) was 42.8 years (SD ±16.6). Pre-existing thyroid disease was documented in 70 (6%) of patients. Normal Thyroid Stimulating Hormone (TSH) test results significantly (p = 0.0001) increased, whilst abnormal TSH test results significantly (p = 0.0001) decreased from baseline to follow-up. Except for gender, the outcome of TSH screening was independent of demographic and clinical diagnoses. Only 16% of TSH tests yielded clinically significant results. Conclusion: The findings of this study do not support the early, routine screening for thyroid dysfunction in psychiatric patients at this facility. It is possible that thyroid screening may present with transient abnormalities of no particular clinical significance, and would therefore not be a cost effective practice.Keywords: Psychiatry; Screening; Thyroid abnormality; Thyroid stimulating hormone

Objective: Medically unexplained symptoms (MUS) are commonly encountered in medical practice. In psychiatry, they are classified mostly as Somatoform Disorders and are often associated with anxiety and depression. The literature suggests that, in some cases, MUS may be ascribed to Somatoform Disorders when, fact, they are “organic” syndromes that are misdiagnosed. In developing countries, with fewer resources, MUS may be more difficult to assess. Method: We undertook a retrospective chart review to examine the demographics, referral pathway, management and diagnostic outcome of subjects (n = 50) referred to psychiatry with MUS over an 18 month period. Results: Subjects with MUS accounted for only 4.5% of the total number of files reviewed. In only 38% of cases did the final diagnosis in psychiatry concur with the referral diagnosis. In 28% of cases a new “organic” diagnosis was made and in 72% of cases a new psychiatric diagnosis was made. Subjects who were diagnosed with “organic” illness were seen fewer times prior to referral to psychiatry and were significantly older than other subjects. Conclusion: In developing countries like SA, a significant number of patients with MUS may have underlying “organic” illness, and most may have psychiatric disorders. Patients with MUS, especially older patients, should be more extensively investigated. Psychiatric referral of these patients is very appropriate. Keywords: Medically unexplained symptoms; Psychiatric disorders; Retrospective review; Somatoform disorders

It has been suggested that antidepressants, including the selective serotonin reuptake inhibitors have neurotrophic effects. Nevertheless, the impact of treatment with a selective serotonin re-uptake inhibitor on regional brain volumes in social anxiety disorder has not been studied. 11 subjects with social anxiety disorder completed magnetic resonance imaging both before and after 12-weeks of treatment with 20 mg/day escitalopram. No increases in structural grey matter were found, but there were decreases in bilateral superior temporal cortex, vermis and the left cerebellum volumes following 12 weeks of treatment with escitalopram. These preliminary findings require replication to determine their reliability, and extension to determine whether or not they are disorder specific.

The role of rhizosphere yeasts as plant nutrient-scavenging microsymbionts in resource-limited Mediterranean-type heathlands is unknown. This study, therefore, focused on quantitative elemental distribution within the roots of a medicinal sclerophyll, Agathosma betulina (Berg.) Pillans, grown under nutrient-poor conditions, and colonized by Cryptococcus laurentii. Micro-particle-induced X-ray emission (PIXE) was used to assess quantitative elemental distribution within the roots of A. betulina inoculated with viable C. laurentii, as well as within roots of control plants that received autoclaved yeast. To aid in the interpretation of heterogeneous elemental distribution patterns, apoplastic barriers (Casparian bands) in root tissues were located using fluorescence microscopy. In addition, root cross-sections were examined for endophytic C. laurentii using light and transmission electron microscopy (TEM). The average concentrations of P, Fe and Mn were significantly (P0.05) higher in roots of yeast-inoculated plants, compared to control plants. Casparian bands were observed in the exodermal cells of both treatments, and the presence of these bands was correlated with elemental enrichment in the epi/exodermal-outer cortical tissues. Light and TEM micrographs revealed that the yeast was not a root endophyte. This is the first report describing the role of a soil yeast as a plant nutrient-scavenging microsymbiont.