Exhaustive Sampling Research Articles

LGBT CEOs and stock returns: Diagnosing rainbow ceilings and cliffs

This study is the first to investigate the implications of lesbian, gay, bisexual, and transgender chief executive officers (LGBT CEOs) for stock performance, using an exhaustive sample of 26 LGBT publicly listed company CEOs since 2000. Firms with openly LGBT CEOs generate a statistically and economically significant monthly alpha of 0.69%− 1.08%, robust to portfolio weighting schemes, estimation frequency, multi-factor asset-pricing models, multicollinearity, sectoral allocation effects, and in subsamples in the United States and globally. The results imply that a “rainbow ceiling” exists with regards to LGBT executives, and that companies they lead are persistently undervalued due to discrimination by investors. LGBT CEOs on average represent small growth stocks with poor past performance, supporting the “rainbow cliff” hypothesis that the LGBT community is overrepresented in precarious leadership positions. Portfolios formed of stocks with LGBT CEOs robustly outperform broad market indices, evidencing attractiveness for ethical investment from both selfish and social perspectives.

Checklist of the bees (Hymenoptera, Apoidea) of New Caledonia.

In a world where insects and notably bees are declining, assessing their distribution over time and space is crucial to evaluate species status and highlight conservation priorities. However, this can be a daunting task, especially in areas such as tropical oceanic islands where exhaustive samplings over time have been lacking. This is the case in New Caledonia, an archipelago located in the southwest Pacific. Historical records of bee species are piecemeal and, although contemporary samplings have significantly advanced our knowledge of the bee fauna of New Caledonia, the status of several species remains to be elucidated. Here, we provide an updated checklist of the 51 bee species recorded for New Caledonia using previous publications and personal samplings. We documented their distribution, origin (i.e. endemic, native or alien) and the year and location of their occurrences. Based on the year of their first capture and the year of their last capture, we determined an occurrence status for each species. Thus, 10 years after the last checklist of the New Caledonian bee fauna, the literature review and recent samplings allowed us to add six new species to the list. Half of them are recently introduced species including one firstly mentioned in this paper (i.e. Hylaeusalbonitens). We consider here that 30 species are effectively present on the territory and the presence of 21 species could not be determined due to a lack of data, which highlights the need to increase sampling efforts across New Caledonia. Given the difficulty of exhaustively sampling the entire archipelago, we would recommend taking, as a starting point, altitude environments and areas where data-deficient species were captured. In a broader perspective, biomolecular analyses are crucial to confirm species identifications. This is also needed to make comparisons between archipelagoes and thus clarify the distribution and status of species at the scale of the southwest Pacific.

Prevalence of Anaemia in Children Aged 6 to 59 Months at the Makiso - Kisangani General Referral Hospital from 2020 to 2022

Anaemia is a public health problem with major consequences for health and in increasing the risk of infant mortality in its severe form. The aim of this study is to determine the prevalence of anaemia in children aged between 6 and 59 months at the Makiso - Kisangani general referral hospital between 2020 and 2022. This was a descriptive cross-sectional study based on a literature review. We took an exhaustive sample of 215 patients who met the inclusion criteria during the study period. To compare our results with previous work, we used descriptive analysis. We observed a prevalence of anaemia of 20.7% in children aged 6 to 59 months, of whom 28.4% were aged 12 to 23 months, with a sex ratio of 1.6 in favour of males. Anaemia, sickle cell disease and malnutrition were the main antecedents, while pallor was the dominant clinical sign, followed by fever and tachycardia. Over 75% of cases were associated with malaria, followed by pneumonia in 26.4%. Severe anaemia accounted for more than half the cases. Management was based on artesunate (82.8%), iron supplementation (81.9%) and transfusion (52.1%). This resulted in 97.2% recovery and 2.8% death. Preventive measures and improved management must therefore be undertaken to combat the aetiologies involved and reduce mortality to below 1%.

Unravelling the ecological drivers of Schistostega pennata (Hedw.) F.Weber & D.Mohr on the Iberian Peninsula: distribution and conservation

ABSTRACT Introduction In the Iberian Peninsula, Schistostega pennata is a rare, acidophilic, Holarctic moss with a characteristic glowing protonema when illuminated by sunlight. It is typically found in dark and humid habitats and is categorised as Threatened or Near Threatened on the Iberian Red Lists. The main aim of this study was to improve knowledge of the distribution, ecology and conservation of S. pennata on the Iberian Peninsula. Methods All data that were available to us for Schistostega pennata on the Iberian Peninsula (relating to distribution, ecology, phenology) were compiled from the literature, citizen science platforms, and our own observations. Species distribution models were created in Maxent to provide the first approximation to its potential Iberian distribution. Key results Twenty-six new populations of Schistostega pennata were located, making a total of 73 records for the Iberian Peninsula, mostly from natural and artificial caves, cavities, mines and crevices, and essentially on siliceous substrates. All observations corresponded to areas with abundant rainfall, mild temperatures, and at least some oceanic influence. Species distribution models predicted an expanded potential climatic range in the Iberian temperate region and several montane Mediterranean areas. Conclusions There remains very little information on Schistostega pennata on the Iberian Peninsula. Existing data coincide with the ecology of the species, although other niches are exploited in other parts of the world that do not seem to occur in this area. It is important to promote its conservation, given the fragmentation of its populations and habitat requirements. Monitoring and initiation of exhaustive sampling campaigns involving citizen science could be a good way to approach this.

Increasing Individual Taxpayer Compliance by Taxpayer Awareness

The objectives of this study were to ascertain and examine the level of taxpayer awareness, individual taxpayer compliance, and the impact of taxpayer awareness on individual taxpayer compliance at the Pratama Tax Office. The employed data analysis techniques encompassed descriptive analysis and verification analysis. The data collection methodology employed in this study entailed disseminating questionnaires to tax officials at a specific Pratama Tax Office in Bandung City. The sample consisted of 40 individuals who were directly involved in the subject matter under investigation. The study employed the Exhaustive Sampling (Census) technique under Nonprobability Sampling. The research findings revealed that the product-moment correlation analysis yielded a coefficient of 0.860, indicating a highly significant and robust relationship between the variables. The results of the simple linear regression analysis indicate that there is a positive relationship between Taxpayer Awareness and Individual Taxpayer Compliance. The equation derived from the analysis is Y = 8.305 + 0.834X, where Y represents the level of Individual Taxpayer Compliance, and X represents Taxpayer Awareness. The coefficient of determination, which measures the proportion of variance in Individual Taxpayer Compliance (Y) explained by Taxpayer Awareness, is 0.739. This condition indicates that Taxpayer Awareness has a significant influence of 73.9% on Individual Taxpayer Compliance. The remaining 26.1% of the variance in Individual Taxpayer Compliance is attributable to other factors not examined in this study, including tax amnesty, e-filing, tax audits, tax penalties, tax bills, and other relevant variables.

Social perception of migrants from “Belarus” from the perspective of voits and mayors from the area of the border strip under the state of emergency (case study)

The crisis on the border between Belarus and three EU countries, i.e. Poland, Lithuania and Latvia, which has been ongoing since the spring of 2021, was an unprecedented attempt in Europe to destabilize the situation inside the Community. Poland faced a challenge it had not faced before. The challenge was faced not only by state authorities and services dedicated to the protection of the Union’s external border, but above all by the residents of the border areas. The influx of illegal migrants inspired by the Belarusian authorities and, as a result, the introduction of the state of emergency affected their lives to the greatest extent, disrupting its rhythm, while the migrants appearing in the farms introduced a hitherto unknown fear of strangers. In this context, the issue of perception and evaluation of the migration crisis and the actions taken by the government from the point of view of local authorities: mayors and village heads of border areas bordering Belarus seems to be extremely interesting cognitively. An empirical survey carried out on a purposive, exhaustive sample of village heads and mayors of municipalities in the border area was devoted to this problem. It should be noted here that the project had the character of a case study. It was diagnostic (exploratory) in nature at this stage and needs to be deepened in the course of further research. The results obtained allow to positively confirm the formulated research hypotheses. The problem of illegal migrants was perceived by the respondents as an issue requiring decisive and immediate action by state institutions. Cooperation with Mateusz Morawiecki’s government and its field bodies was positively assessed. The mayors mostly approved of the emergency measures treating them as necessary to resolve the crisis.

PLANET: A Multi-objective Graph Neural Network Model for Protein-Ligand Binding Affinity Prediction.

Predicting protein-ligand binding affinity is a central issue in drug design. Various deep learning models have been published in recent years, where many of them rely on 3D protein-ligand complex structures as input and tend to focus on the single task of reproducing binding affinity. In this study, we have developed a graph neural network model called PLANET (Protein-Ligand Affinity prediction NETwork). This model takes the graph-represented 3D structure of the binding pocket on the target protein and the 2D chemical structure of the ligand molecule as input. It was trained through a multi-objective process with three related tasks, including deriving the protein-ligand binding affinity, protein-ligand contact map, and ligand distance matrix. Besides the protein-ligand complexes with known binding affinity data retrieved from the PDBbind database, a large number of non-binder decoys were also added to the training data for deriving the final model of PLANET. When tested on the CASF-2016 benchmark, PLANET exhibited a scoring power comparable to the best result yielded by other deep learning models as well as a reasonable ranking power and docking power. In virtual screening trials conducted on the DUD-E benchmark, PLANET's performance was notably better than several deep learning and machine learning models. As on the LIT-PCBA benchmark, PLANET achieved comparable accuracy as the conventional docking program Glide, but it only spent less than 1% of Glide's computation time to finish the same job because PLANET did not need exhaustive conformational sampling. Considering the decent accuracy and efficiency of PLANET in binding affinity prediction, it may become a useful tool for conducting large-scale virtual screening.

Shea Butter Oil Biodiesel Synthesized Using Snail Shell Heterogeneous Catalyst: Performance and Environmental Impact Analysis in Diesel Engine Applications

The implementation of biodiesel in internal combustion engines has been observed to enhance engine performance and mitigate the discharge of toxic gaseous emissions from the engine. In this research, Shea Butter Oil Biodiesel (SBOB) was used to operate a diesel engine to analyze the performance and emissions characteristics. Shea Butter Oil Biodiesel (SBOB) was blended with petroleum diesel in ratios 0:100 (B0), 25:75 (B25), 50:50 (B50), 75:25 (B75), and 100:0 (B100). The torque, brake power (BP), and brake thermal efficiency (BTE) of the engine were determined. Gaseous emissions from the engine’s combustion were characterized using the BOSEAN BH-4S portable multi-gas detector, while the organic emissions compositions were detected and quantified using Gas Chromatography-Mass Spectrometry (GC-MS). The fuel properties of SBOB and its blends were found to be within the range of acceptable standards. However, the carbon content, sulphur content, heating value, and ash content of the blends decreased from 0.68 to 0.12 wt %, 0.04 to 0.00 wt %, 44.2 to 34.2 MJ/kg, and 0.020 to 0.010 wt %, respectively. The engine torque, brake power, BTE, and engine vibrations were found to reduce when the biodiesel blends were used. Besides the diesel fuel, the biodiesel blend, B25, produced the best engine performance characteristics with 8.50 Nm torque, 1780.95 W BP, and 90.29% BTE. The B100 produced the lowest concentrations of carbon emissions, viz. 520 ppm CO and 1.0% CO2. The NO and NO2 concentrations were found to increase for all the biodiesel blends used. The NO and NO2 concentrations were measured as 230 ppm and 210 ppm for B0, respectively, and 250 ppm and 235 ppm for B25, respectively. The research showed that SBOB has improved engine performance and lowered the emissions profile of CO and CO2 compared with petroleum diesel. The GCMS analysis confirmed that some harmful organic compounds were present in the emissions profile obtained from the exhaust samples of the diesel engine at various compositions.

The Effect of Deppamil Dangke to Pregnant Women with Chronic Energy Deficiency on the Outcome of Newborn Babies in Enrekang Regency

Chronic energy deficiency (CED) tends to occur in pregnant women and carry detrimental effects, especially on the women during labour and on the fetus. Therefore, it is extremely important to increase nutritional intake during pregnancy for optimized newborn outcome. There are a variety of ways to treat CED, one of which is to provide additional food during pregnancy. This study aims to determine the effect of Deppamil Dangke to pregnant women with CED on the outcome of newborns. This research method used a quasi-experimental design conducted for 18 weeks in Enrekang Regency, with a population of 28 pregnant women > 20 weeks gestation who then used a exhaustive sampling technique where the sample was divided into two consisting of 14 intervention samples and 14 control samples. The results of the study were tested using Mann Whitney showing the value of ρ > α (0.05), which means that there was no difference in the outcome of newborns between the intervention group and the control group. Conclusion. Consuming Deppamil Dangke did not have a direct effect on the outcome of newborns, even though the difference was not significant, but the average outcome of newborns in mothers who consumed Deppamil Dangke + PMT was in the normal category.

The Effect of Deppamil Dangke in Increasung Upper Arm Circumference and Haemoglobin Levels in Pregnant Women with Chronic Energy Deficiency

The prevalence of chronic energy deficiency in pregnant women in Indonesia is relatively high, requiring some actions to be taken to lower it. This study aims to analyze the roles of deppamil dangke administration in increasing upper arm circumference and haemoglobin levels in pregnant women with chronic energy deficiency (CED) in Enrekang Regency. This research is of the quasi-experimental type with a non-equivalent control group design. The population consisted of 28 CED pregnant women with gestational age >20 weeks using exhaustive sampling technique, there were two test groups involved, namely, an intervention group and a control group, each consisting of 14 samples. The intervention group was given deppamil dangke 6 pieces/day (60 gr) plus government food supplement while the control group was given government food supplement 3 pieces/day (100 gr) with an intervention duration of 18 weeks. UAC and haemoglobin levels were measured before and after the intervention. The results of this study indicated that there was an increase in the size of UAC in both groups but not significantly different as both the intervention and control groups experienced increases in upper arm circumference with the same p value (p = 0.001). But it was significant in increasing the hemoglobin level of CED pregnant women because the intervention group experienced a significant increase with a p- value of 0.020 while the control group had a p value of 0.506. Future.

Evaluation of the quality of prenatal consultation at the Community Health Center of Ber in the Health District of Tombouctou

The aim was to evaluate the quality of the prenatal consultation at the Community Health Center of Ber, in the Health District of Tombouctou. Patients and Methods: Descriptive cross-sectional study with analytical aim including an observational flight, a quantitative component with exhaustive sampling and a qualitative component following a reasoned non-probabilistic sampling involving 347 pregnant women and which took place over 45 days from November 15 to December 31, 2019 at the Ber CSCom in the Tombouctou Health District. Results: The age group was between 24 and 33 years old with 48.4%. The majority of users of SR services and care consulted for a CPN1 with 70%. 58.8% had a history of multiparty. Only 12.4% of the pregnancies monitored were identifiedas at risk. 0.6% of the users presented danger signs. The majority of users received a MILD with a rate of 65.4%.The qualitative study allowed us to know the knowledge, attitudes and practices of mothers, grandmothers, women leaders, ATR and men on CPN. The observational study allowed us to evaluate the reception, the quality of the care, the profile of the staff and the availability of medicines, the caregiver-caregiver relationship. Conclusion: The performance of the CPN services at the Ber CSCom was judged satisfactory according to the rating parameters used in the present study. It should be optimal to allow all pregnant women and users to benefit from it.

Maastrichtian palynological assemblages from the Chorrillo Formation, Patagonia, Argentina

The Chorrillo Formation is an uppermost Cretaceous continental sequence cropping out in the southernmost region of Patagonia. Recent field trips carried out in the region allowed the recognition of a highly diverse record of continental vertebrates, invertebrates, and plants that inhabited the region during the latest Cretaceous. In this study, a palynological analysis derived from an exhaustive sampling in the unit is presented. The recovered taxa include 44 spore species, 28 gymnosperm and 55 angiosperm pollen taxa, as well as 7 algae, and fungal remains. Two new taxa of unknown affinities (Acylomurus silviae sp. nov. and Lusatisporis choiols sp. nov.) and a new alga (Sphaeroplea striatocristata sp. nov.,) are proposed. Taxonomic composition of the palynological assemblages suggest humid and temperate to warm climatic conditions. Based on the stratigraphic range of the identified taxa, a Maastrichtian age is suggested, coincident with previous interpretations derived from the stratigraphic relationships of the Chorrillo Formation. Comparisons with other latest Cretaceous to Danian assemblages from southern Gondwana, carried out using multivariate statistical methods, indicate that the assemblage from the Chorrillo Formation has greatest similarities with the palynological assemblages of the Maastrichtian La Irene and La Anita formations, the upper levels of the Monte Chico Formation, and with the Maastrichtian levels of the Lefipán Formation, all units cropping out in central and southern Patagonia.

The role of additives in improving the flammability and calorific value of leather shavings and the binding of chromium compounds in ash

Leather processing companies are struggling with the problem of increasing costs of post-production waste disposal. Therefore, the issue of thermal waste disposal at the plant and the use of generated heat in the production process is becoming more and more popular. Leather waste on its own does not allow for autothermal combustion despite the sufficient higher heating value (HHV). Therefore the Authors proposed to improve the flammability of the fuel by adding a small amount of wood sawdust to leather waste and produce premixed pellets. Six such samples were incinerated in a laboratory-scale reactor, which enables the simultaneous measurement of characteristic temperatures, exhaust gas analysis and sample mass loss rate. Research has shown that even a small addition of sawdust enables a stable combustion process and does not cause the formation of sinters. In addition, studies of the ash showed that in the case of chromium-containing waste, a large part of it remained in the ash in the form of Cr2O3. Nevertheless, very fine ash causes the small fraction chromium to be carried with the flue gas stream, therefore controlled agglomeration of the ash structure would be advisable in the final installation. Emission analysis showed high and moderately high NOx and SO2 emissions, decreasing with the increase in the amount of sawdust addition in the sample. Research has shown that leather waste is not a burden, but can be an attractive and safe source of energy for the company, while improving waste management in a circular economy.

Effects of particle-bound polycyclic aromatic hydrocarbons and plasticisers from different traffic sources on the human alveolar epithelial cell line A549

Road traffic represents a major source of particulate matter (PM), which is considered the most harmful pollutant for humans. This work aimed to evaluate the toxic effects of polycyclic aromatic hydrocarbons (PAHs) and plasticisers extracted from PM emitted by traffic, including exhaust samples, samples collected in a road tunnel and simultaneously in a nearby urban background atmosphere, and samples from the wear of distinct types of brakes. Different biological endpoints were investigated after exposing human alveolar epithelium A549 cells to the organic extracts: viability, cell cycle alterations and levels of intracellular reactive oxygen species (ROS). The particulate extracts from the wear of low steel brake pads induced greater decreases in cell viability. It was observed that cytotoxicity is more dependent on the individual composition of PAHs than on the global concentration. Exhaust samples from heavy-duty Euro V vehicles induced more toxic effects than Euro VI. Among Euro V vehicles, the exhaust of GTL was the most toxic. The composite weekly sample of the urban background atmosphere showed to be extremely toxic, decreasing cell viability to 2.66%, while the daily road tunnel samples caused a decrease of up to 83.6% at most. In the particulate extracts of the urban background atmosphere, retene and naphthalene were found, which were absent or present at trace levels in the tunnel. Irrespective of the sample, although some changes were observed in the A549 cell cycle after 24 h exposure in all the phases, the differences in the mean values were not great enough to exclude the possibility of random variability. When the results from the three phases (G0/G1, S and G2/M) of the cells exposed to all PM extracts were compared to the control, no statistically significant difference was detected. Regardless of the sample type, no significant increases in cellular ROS levels were observed either.

Environmental factors shaping copepod distributions in cave waters of the Lessinian unsaturated karst (NE-Italy)

The unsaturated karst represents a transitional zone connecting the land surface to the water table of the underlying saturated zone through percolating water and small perched aquifers. It constitutes a significant groundwater reservoir and hosts a high biodiversity of specialized and endemic species. Whereas investigating this ecotone can shed light on the invertebrate diversity of the whole karst system, ecological studies in the unsaturated karst have been hampered by access, mapping, and sampling challenges. We studied the unsaturated zone of 52 caves in the Lessinian Massif (NE-Italy), which is dominated by carbonate rocks interspersed with spot areas composed mainly of igneous rocks. Our aim was to understand which ecological and historical factors may have shaped the distribution of the groundwater crustacean copepods at a regional spatial scale in the Lessinian unsaturated karst. We collected 33 species belonging to the orders Harpacticoida and Cyclopoida. Species richness estimators and related species accumulation curves suggest an exhaustive sampling effort. A hydrologic analysis performed in a Geographic Information System environment divided the study area in three distinct drainage basins: Eastern Lessini, Lessinian Core, and Western Lessini. Regression analyses indicated that richness of non-stygobitic copepods (i.e., surface-water species which exploit groundwater for different purposes) was mainly driven by inter-basin differences. Richness of stygobitic copepods (i.e., obligate groundwater dwellers) was instead strongly related to lithological features and responded negatively to surface thermal variability. Next, we used a kernel density estimation to spatially explore diversity patterns in the area. The highest density of stygobitic harpacticoids was identified in the Eastern Lessinian basin, which is lithologically more heterogeneous and surrounded by practically non-aquiferous igneous rocks that may limit dispersal. Conversely, the Western Lessinian basin hosted a high density of stygobitic cyclopoid species. This spatial pattern suggests different colonization pathways for the two taxa, with a strong effect of igneous rocks in hampering dispersal of most harpacticoids. Lithological barriers seemingly did not affect non-stygobitic copepods, which were found across the whole area. Altogether, these results emphasize the key role played by the interaction of hydrological features, climate, and lithology in determining different copepod biodiversity patterns in the unsaturated karst.

Update on C-Cell Neuroendocrine Neoplasm: Prognostic and Predictive Histopathologic and Molecular Features of Medullary Thyroid Carcinoma.

Medullary thyroid carcinoma (MTC) is a C-cell-derived epithelial neuroendocrine neoplasm. With the exception of rare examples, most are well-differentiated epithelial neuroendocrine neoplasms (also known as neuroendocrine tumors in the taxonomy of the International Agency for Research on Cancer [IARC] of the World Health Organization [WHO]). This review provides an overview and recent evidence-based data on the molecular genetics, disease risk stratification based on clinicopathologic variables including molecular profiling and histopathologic variables, and targeted molecular therapies in patients with advanced MTC. While MTC is not the only neuroendocrine neoplasm in the thyroid gland, other neuroendocrine neoplasms in the thyroid include intrathyroidal thymic neuroendocrine neoplasms, intrathyroidal parathyroid neoplasms, and primary thyroid paragangliomas as well as metastatic neuroendocrine neoplasms. Therefore, the first responsibility of a pathologist is to distinguish MTC from other mimics using appropriate biomarkers. The second responsibility includes meticulous assessment of the status of angioinvasion (defined as tumor cells invading through a vessel wall and forming tumor-fibrin complexes, or intravascular tumor cells admixed with fibrin/thrombus), tumor necrosis, proliferative rate (mitotic count and Ki67 labeling index), and tumorgrade (low- or high-grade) along with the tumor stage and the resection margins. Given the morphologic and proliferative heterogeneity in these neoplasms, an exhaustive sampling is strongly recommended. Routine molecular testing for pathogenic germline RET variants is typically performed in all patients with a diagnosis of MTC; however, multifocal C-cell hyperplasia in association with at least a single focus of MTC and/or multifocal C-cell neoplasia are morphological harbingers of germline RET alterations. It is of interest to assess the status of pathogenic molecular alterations involving genes other than RET like theMET variants in MTC families with no pathogenic germline RET variants. Furthermore, the status of somatic RET alterations should be determined in all advanced/progressive or metastatic diseases, especially when selective RET inhibitor therapy (e.g., selpercatinib or pralsetinib) is considered. While the role of routine SSTR2/5 immunohistochemistry remains to be further clarified, evidence suggests that patients with somatostatin receptor (SSTR)-avid metastatic disease may also benefit from the option of 177Lu-DOTATATE peptide radionuclide receptor therapy. Finally, the authors of this review make a call to support the nomenclature change of MTC to C-cell neuroendocrine neoplasm to align this entity with the IARC/WHO taxonomy since MTCs represent epithelial neuroendocrine neoplasms of endoderm-derived C-cells.

Chemical characterization of combustion engine exhaust and assessment of helicopter deck operator occupational exposures on an offshore frigate class ship

Diesel engine exhaust (DE) consists of a complex mixture of gases and aerosols, originating from sources such as engines, turbines, and power generators. It is composed of a wide range of toxic compounds ranging from constituents that are irritating to those that are carcinogenic. The purposes of this work were to characterize DE originating from different engine types on a ship operating offshore and to quantify the potential exposure of workers on the ship’s helicopter deck to select DE compounds. Sampling was conducted on a Norwegian Nansen-class frigate that included helicopter operations. Frigate engines and generators were fueled by marine diesel oil, while the helicopter engine was fueled by high flash point kerosene-type aviation fuel. Exhaust samples were collected directly from the stack of the diesel engine and one of the diesel generator exhaust stacks, inside a gas turbine exhaust stack, and at the exhaust outlet of the helicopter. To characterize the different exhaust sources, non-targeted screening of volatile and semi-volatile organic compounds was performed for multiple chemical classes. Some of the compounds detected at the sources are known irritants, such as phthalic anhydride, 2,5-dyphenyl-p-benzoquinone, styrene, cinnoline, and phenyl maleic anhydride. The exhaust from the diesel engine and diesel generator was found to contain the highest amounts of particulate matter and gaseous compounds, while the gas turbine had the lowest emissions. Personal exposure samples were collected outdoors in the breathing zone of a helicopter deck operator over nine working shifts, simultaneously with stationary measurements on the helicopter deck. Elemental carbon, nitrogen dioxide, and several volatile organic compounds are known to be present in DE, such as formaldehyde, acrolein, and phenol were specifically targeted. Measured DE exposures of the crew on the helicopter deck were variable, but less than the current European occupational exposure limits for all compounds, except elemental carbon, in which concentration varied between 0.5 and 37 µg/m3 over nine work shifts. These findings are among the first published for this type of working environment.

Prevalence of Hepatitis C among Blood Donors at the National Blood Transfusion Center of Bamako in Mali

Introduction and purpose of the study: The overall prevalence of HCV among adults in sub-Saharan Africa has increased from 3.82 to 3.94% (3). We find a disproportionate prevalence of viral hepatitis C in blood donors in several national blood transfusion centers in Sub-Saharan Africa and the aim of our work was to study the seroprevalence of hepatitis C in blood donors from the center national blood transfusion center of Bamako Methods: This was a descriptive cross-sectional study that took place at the CNTS national blood transfusion center in Bamako from July to December 2019. Our study concerned blood donors (volunteers and relatives) presenting to the CNTS in Bamako during the study period. It focused on an exhaustive random sample of CNTS blood donors, the variables studied were gender, marital status, type of donor HCV+, HCV-, age and number of donations. Serodiagnosis was determined by the ELISA technique. Results: We collected 250 samples, the 26-35 age group was the most represented with 49.6%; the prevalence of hepatitis C was 1%. Hepatitis C marker positivity has been observed in family donors. Conclusion: The seroprevalence of hepatitis C during our study was 1%. The ELISA technique with monolisa HCV reagent was used as the method. We found a relationship between seroprevalence and few sociodemographic aspects.

Assessment of Variability Sources in Grape Ripening Parameters by Using FTIR and Multivariate Modelling.

The variability in grape ripening is associated with the fact that each grape berry undergoes its own biochemical processes. Traditional viticulture manages this by averaging the physicochemical values of hundreds of grapes to make decisions. However, to obtain accurate results it is necessary to evaluate the different sources of variability, so exhaustive sampling is essential. In this article, the factors "grape maturity over time" and "position of the grape" (both in the grapevine and in the bunch/cluster) were considered and studied by analyzing the grapes with a portable ATR-FTIR instrument and evaluating the spectra obtained with ANOVA-simultaneous component analysis (ASCA). Ripeness over time was the main factor affecting the characteristics of the grapes. Position in the vine and in the bunch (in that order) were also significantly important, and their effect on the grapes evolves over time. In addition, it was also possible to predict basic oenological parameters (TSS and pH with errors of 0.3 °Brix and 0.7, respectively). Finally, a quality control chart was built based on the spectra obtained in the optimal state of ripening, which could be used to decide which grapes are suitable for harvest.

Induced ion correlations lead to DNA attraction in manganese.

Divalent counterions show the ion specificity effect. In a free solution, Mn2+ ions can condense DNA into a disorder bundle of structures while the same valence Mg2+ ions dissolve DNA assemblies. Theoretical models were proposed to explain the Mn2+-induced condensation of DNA with limited success. Here, we employ all-atom molecular simulations to investigate the ion specificity effect on DNA-DNA interactions. An exhaustive sampling of inter-helical distance and angular orientations afforded by metadynamics simulations allowed us to construct the free energy surface of the DNA-DNA interactions. In excellent agreement with experiments, we observe that dsDNA strands show attraction in the presence of Mn2+, while they remain repulsive at the same ionic strength in MgCl2. To explain the disparate behavior of the two divalent cations, we investigate cation distributions and preferential binding sites. We observe significant differences in binding modes between Mn2+ and Mg2+. The manganese ions bind prevalently to the phosphate backbone, while magnesium ions occupy both backbone and the major groove of the DNA. We develop a simple like-charge attraction model based on the preferential binding sites derived from simulations. Our model explains the observed differences between the two cations successfully. It highlights the importance of induced ion correlations between adjacent pairs as the mechanism leading to attraction. Our results shed light into Mn2+ induced like charge attraction mechanism of DNA. The method can be extended to study other condensing agents.