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Silver nanoplates (SNPs) are particularly attractive in surface-enhanced Raman scattering (SERS) activity due to their unique physicochemical properties, including localized surface plasmon resonance (LSPR) and strongly electromagnetic "hot spots" in the vicinity of their tips and edges. In this study, we report a novel, rapid, and simplified methodology for preparing SNPs using a one-pot synthesis approach with AgNO3, NaBH4, TSC, PVP, and an oxidation agent, H2O2. By adjusting precursor ratios, the LSPR peak can be easily adjusted from 400 to 800 nm, with a change in morphology from spherical, undefined structures, nano-disks, and triangular. In this study, Na2CO3 was added to the reaction to react with excess H2O2 to obtain long-term stable nanoparticles in a colloidal solution for 21 days. Crystal violet (CV) dye was used as a Raman probe to evaluate the SERS performance of SNP substrates at different diameters (35, 60, 120, 210 nm). The results showed that SERS activity was inverse to the SNP diameter. The finite-difference time domain (FDTD) was employed to compute the E-field around SNPs, indicating that E-field intensity depends on the SNPs' size, shape, and LSPR peak position. The 35 nm SNP substrates exhibited high sensitivity and good reproductivity in detecting CV dye, with a limit of detection (LOD) of 0.020 mg L−1 and a limit of quantification (LOQ) of 0.060 mg L−1. Additionally, SNP substrates can detect sulfathiazole (STZ) at trace-level concentrations, with LOD and LOQ of 0.031 and 0.095 mg L−1, respectively. These studies on silver nanoplate substrates displayed potential for further ultra-trace analysis applications in organic compounds. [ABSTRACT FROM AUTHOR]

The article presents unique research conducted in Bidoup-Nui Ba National Park, Vietnam, focusing on the biogeochemical element migration in soil and plants. The study aimed to identify element content changes, biological accumulation, and biogeochemical mobility during wet and dry seasons across different landscape conditions. The research revealed the active elements involved in migration and accumulation, assessed mobility and accumulation in bamboo organs, and highlighted the peculiarities within the "soil-plant" system. The study found that the uptake of certain microelements by plants is influenced by landscape facies and moisture conditions. For example, Zn, Cu, and Co were introduced through plant litter during the wet season and accumulated, while Mo accumulation was more pronounced in the dry season. Furthermore, the research observed variations in biological uptake by bamboo organs, with different landscape conditions and seasons playing a role. The biogeochemical mobility of elements in bamboo organs increased significantly with soil moisture during the wet season. Overall, the research provided insights into element accumulation and biogeochemical migration. Notably, the accumulation of element B was found to increase with soil moisture, while its reduction was associated with slope process activation during the wet season.

Tropical ecosystems play an important role in the environment. Coastal areas are subjected to a wide range of impacts and pollution, which have drawn worldwide attention over the past few decades. Comprehensive studies of heavy metal content in soils worldwide are extremely important for assessing and predicting ecological risks. Very few studies have been devoted to a complete study of the physicochemical characteristics of soils, assessment of heavy metal accumulation in coastal zones along the Djibouti coast, and potential ecological risks. The study investigated the physico-chemical characteristics of soil, assessed the accumulation of heavy metals in coastal zones along the Djibouti coast, and analyzed the potential environmental risks associated with the presence of heavy metals in the studied soils. Analysis of heavy metals and trace elements in the soils of the coastal areas of Djibouti revealed that the levels of these elements are lower than in soils of the Red Sea coast and are in line with WHO and other international standards. All heavy metals in the soil of the studied area demonstrate low levels of potential ecological risk. The soils of the studied areas, overall, have not undergone significant heavy metal pollution and can be considered suitable for various types of use.

The study of technogenic pollution of soils with heavy metals (HM) is an essential task for ecology. The analysis of the content of HMs in the park's soils shows the degree of pollution and the sources of its occurrence. The study of the elemental composition of soils is an objective method for assessing the state of the ecosystem. To determine the current state of heavy metal contamination in forest soils, the concentrations of their total forms were analyzed. Heavy metals, including Zn, Pb, Cr, Cu, Hg, Cd, and As, were found in the study area. In addition, the threat of contamination with Cd and As has been identified. The calculation of the total pollution coefficient allows us to assess the level of pollution for the dry season (Zc = 18.45-28.24, average 22.45) as average (moderately hazardous) and for the wet season (Zc = 0.01-5.11, average 1.96) as permissible. This indicates an unfavorable environmental situation. The content of heavy metals in soils depends on the season. Observations show that at the end of the wet season, the concentration of heavy metals decreases, while it increases in the period after the dry season.

Article Highlights - Camellia dalatensis and Camellia capitata are critically endangered species. - Habitat loss and deforestation threaten the survival of these Camellia species. - Vegetative propagation aids conservation of critically endangered Camellia species. - Rooting success depends on cutting types, growth regulators, and substrate mix. - Research aids conservation efforts for Vietnam’s rare and vulnerable flora. Abstract Camellia dalatensis (V. D. Luong, Ninh & Hakoda) and Camellia capitata (Orel, Curry & Luu) are classified as critically endangered (CR) by the IUCN. Conservation solutions for these two species have not yet been fully implemented, while wild populations are declining. This research on vegetative propagation examined the efficacy of indole-3-butyric acid (IBA in solution or in powdered activated charcoal), cutting types (terminal shoot or stem cuttings), and substrates for the growth of cuttings (sand-coir dust mixes) on rooting efficiency. The highest rooting of C. dalatensis was observed in terminal shoot cuttings at 1,000 ppm IBA, and 25% sand and 75% coir dust substrate. Maximum values obtained were survival 95.6%, rooting percentage 88.9%, number of roots per cutting 6.9, root length 6.2 cm, and rooting index 42.9. For C. capitata, superior rooting was obtained with semi-hardwood cuttings, at 1,500 ppm IBA, and equal parts of sand and coir dust as substrate. Camellia capitata was more difficult to root, with maximum values of 65.6% survival, 52.2% rooting, 2.8 roots per cutting, 2.9 cm root length, and rooting index of 8.1. The results of this study can be used to support further propagation and conservation of these two endangered species.

Background Radiotherapy is an essential component of cancer treatment, yet many countries do not have adequate capacity to serve all patients who would benefit from it. Allocation systems are needed to guide patient prioritization for radiotherapy in resource-limited contexts. These systems should be informed by allocation principles deemed relevant to stakeholders. This study explores the ethical dilemmas and views of decision-makers engaged in real-world prioritization of scarce radiotherapy resources at a cancer center in Rwanda in order to identify relevant principles. Methods Semi-structured interviews were conducted with a purposive sample of 22 oncology clinicians, program leaders, and clinical advisors. Interviews explored the factors considered by decision-makers when prioritizing patients for radiotherapy. The framework method of thematic analysis was used to characterize these factors. Bioethical analysis was then applied to determine their underlying normative principles. Results Participants considered both clinical and non-clinical factors relevant to patient prioritization for radiotherapy. They widely agreed that disease curability should be the primary overarching driver of prioritization, with the goal of saving the most lives. However, they described tension between curability and competing factors including age, palliative benefit, and waiting time. They were divided about the role that non-clinical factors such as social value should play, and agreed that poverty should not be a barrier. Conclusions Multiple competing principles create tension with the agreed upon overarching goal of maximizing lives saved, including another utilitarian approach of maximizing life-years saved as well as non-utilitarian principles, such as egalitarianism, prioritarianism, and deontology. Clinical guidelines for patient prioritization for radiotherapy can combine multiple principles into a single allocation system to a significant extent. However, conflicting views about the role that social factors should play, and the dynamic nature of resource availability, highlight the need for ongoing work to evaluate and refine priority setting systems based on stakeholder views.

The Caspian region represents a complex and unique system of terrestrial, coastal, and aquatic environments, marked by an exceptional landscape and biological diversity. This diversity, however, is increasingly threatened by substantial anthropogenic pressures. One notable impact of this human influence is the rising concentration of pollutants atypical for the atmosphere. Advances in science and technology now make it possible to detect certain atmospheric pollutants using remote Earth observation techniques, specifically through data from the Sentinel-5 satellite, which provides continuous insights into atmospheric contamination. This article investigates the dynamics of atmospheric pollution in the southwestern part of the Caspian Sea basin using Sentinel-5P satellite data and the cloud-computing capabilities of the Google Earth Engine (GEE) platform. The study encompasses an analysis of concentrations of seven key pollutants: nitrogen dioxide (NO2), formaldehyde (HCHO), carbon monoxide (CO), ozone (O3), sulfur dioxide (SO2), methane (CH4), and the Aerosol Index (AI). Spatial and temporal variations in pollution fields were examined for the Caspian region and the basins of the seven rivers (key areas) flowing into the Caspian Sea: Sunzha, Sulak, Ulluchay, Karachay, Atachay, Haraz, and Gorgan. The research methodology is based on the use of data from the Sentinel-5 satellite, SRTM DEM data on absolute elevations, surface temperature data, and population density data. Data processing is performed using the Google Earth Engine cloud-computing platform and the ArcGIS software suite. The main aim of this study is to evaluate the spatiotemporal variability of pollutant concentration fields in these regions from 2018 to 2023 and to identify the primary factors influencing pollution distribution. The study’s findings reveal that the Heraz and Gorgan River basins have the highest concentrations of nitrogen dioxide and Aerosol Index levels, marking these basins as the most vulnerable to atmospheric pollution among those assessed. Additionally, the Gorgan basin exhibited elevated carbon monoxide levels, while the highest ozone concentrations were detected in the Sunzha basin. Our temporal analysis demonstrated a substantial influence of the COVID-19 pandemic on pollutant dispersion patterns. Our correlation analysis identified absolute elevation as a key factor affecting pollutant distribution, particularly for carbon monoxide, ozone, and aerosol indices. Population density showed the strongest correlation with nitrogen dioxide distribution. Other pollutants exhibited more complex distribution patterns, influenced by diverse mechanisms associated with local emission sources and atmospheric dynamics.

A new species of Sterculia from Vietnam – S. konchurangensis – is described, illustrated, and compared with the similar S. lanceolata. S. konchurangensis differs from S. lanceolata by the length of the petiole (7.0–9.5 vs. 25–35 mm), shape of the leaf blade (obovate or elliptic vs. elliptic, lanceolate or elliptic-lanceolate), length of the leaf blade (6–8 vs. 9–20 cm), and length of the calyx lobe (11–12.5 vs. 4–6 mm). A diagnostic key of the 22 Sterculia species occurring in Vietnam is also provided.

Since the end of the 20th century, the use of geographic information systems and digital elevation models has reduced the time required for and improved the quality of morphometric analysis of the relief within river basins. However, researchers are constantly faced with the problem of choosing the most accurate and suitable digital terrain model for their task. Many global, regional, and local digital elevation models are available. In this study, we comparatively analyzed the accuracy of the ASTER GDEM, ALOS World 3D, Copernicus DEM, and SRTM DEM spatial datasets for the purpose of catchment basin modeling for the river basins of the northwestern slope of the Crimean Mountains (Zapadnyy Bulganak, Alma, Kacha, Belbek, and Chernaya Rivers) as an example. For each river basin, we calculated the systematic, root mean square, mean absolute, standard root mean square (Bessel’s correction), and centered mean absolute errors by comparing ASTER GDEM, ALOS World 3D, Copernicus DEM, and SRTM DEM data with a 1:100,000 topographic map within the considered river basins. We found the smallest error values for the Copernicus DEM and ALOS World 3D datasets; furthermore, we used the Copernicus DEM dataset to model the river basins and sub-basins of the northwestern slope of the Crimean Mountains. As a result, we identified these river basins and sub-basins for the Zapadnyy Bulganak, Alma, Kacha, Belbek, and Chernaya Rivers, which are represented by stream basins, valleys, gullies, and ravine systems.

BackgroundThe number of mobile health apps is rapidly increasing. This means that consumers are faced with a bewildering array of choices, and finding the benefit of such apps may be challenging. The significant international burden of breast cancer (BC) and the potential of mobile health apps to improve medical and public health practices mean that such apps will likely be important because of their functionalities in daily life. As the app market has grown exponentially, several review studies have scrutinized cancer- or BC-related apps. However, those reviews concentrated on the availability of the apps and relied on user ratings to decide on app quality. To minimize subjectivity in quality assessment, quantitative methods to assess BC-related apps are required. ObjectiveThe purpose of this study is to analyze the content and quality of BC-related apps to provide useful information for end users and clinicians. MethodsBased on a stepwise systematic approach, we analyzed apps related to BC, including those related to prevention, detection, treatment, and survivor support. We used the keywords “breast cancer” in English and Korean to identify commercially available apps in the Google Play and App Store. The apps were then independently evaluated by 2 investigators to determine their eligibility for inclusion. The content and quality of the apps were analyzed using objective frameworks and the Mobile App Rating Scale (MARS), respectively. ResultsThe initial search identified 1148 apps, 69 (6%) of which were included. Most BC-related apps provided information, and some recorded patient-generated health data, provided psychological support, and assisted with medication management. The Kendall coefficient of concordance between the raters was 0.91 (P2 years ago, or by individuals, had significantly lower MARS scores compared to other apps (P

Abstract: Cyanobacteria have long been thought to induce the formation of Ca‐carbonates as secondary by‐products of their metabolic activity, by shifting the chemical composition of their extracellular environment to conditions favoring mineral precipitation. Some cyanobacterial species forming Ca‐carbonates intracellularly were recently discovered. However, the environmental conditions under which this intracellular biomineralization process can occur and the impact of cyanobacterial species forming Ca‐carbonates intracellularly on extracellular carbonatogenesis are not known. Here, we show that these cyanobacteria can form Ca‐carbonates intracellularly while growing in extracellular solutions undersaturated with respect to all Ca‐carbonate phases, that is, conditions thermodynamically unfavorable to mineral precipitation. This shows that intracellular Ca‐carbonate biomineralization is an active process; that is, it costs energy provided by the cells. The cost of energy may be due to the active accumulation of Ca intracellularly. Moreover, unlike cyanobacterial strains that have been usually considered before by studies on Ca‐carbonate biomineralization, cyanobacteria forming intracellular carbonates may slow down or hamper extracellular carbonatogenesis, by decreasing the saturation index of their extracellular solution following the buffering of the concentration of extracellular calcium to low levels. [ABSTRACT FROM AUTHOR]

PURPOSENephroblastoma is a highly curable pediatric cancer that requires multidisciplinary care. Few reports have assessed long-term treatment outcomes in low-resource settings using a task-shifting model of care. We report outcomes of a large cohort and factors associated with survival.METHODSWe performed a retrospective chart review of all patients with nephroblastoma presenting to the Butaro Cancer Center of Excellence in Rwanda between July 2012 and June 2018.RESULTSIn total, 136 patients were identified and treated according to International Society of Pediatric Oncology guidelines for low-income settings. Median age at diagnosis was 39.7 months (interquartile range, 25.3-61.8 months); 56.6% were female. Sixty-one (44.9%) patients presented with stage I-III disease, 35 (25.7%) with stage IV disease, and 6 (4.4%) with stage V disease; the remainder were unstaged (n = 34; 25.0%). Most patients completed surgery (n = 97; 71.3%) and postoperative chemotherapy (n = 82; 60.2%); 17 patients received radiotherapy. With a median follow-up time of 18.1 months, 44.9% of patients were alive, 41.9% had died, 8.8% were lost to follow-up, and 4.4% were referred for palliative care or declined further care at the end of the study. Three-year overall survival was 57.5% (95% CI, 48.1 to 65.8) for the entire cohort, and 80.1% (95% CI, 66.8 to 88.5) and 44.0% (95% CI, 26.8 to 60.0) for stages I-III and IV-V, respectively.CONCLUSIONWe demonstrate that patients with nephroblastoma can be successfully treated in a low-resource setting. Survival remains lower than in high-income countries, in part due to early deaths, contributing to approximately 30% of patients not being medically able to receive surgical intervention. Next steps include the development of strategies that focus on earlier diagnosis, supportive care during the early phases of therapy, and efficient and timely transitions between specialties for multimodal care.

PURPOSEIn describing our ten-year experience with treating chronic myeloid leukemia (CML) as part of the Glivec Patient Assistance Program (GIPAP) in rural Rwanda, we evaluate (1) patient characteristics and treatment outcomes, (2) resource-adapted management strategies, and (3) the impact of diagnostic capacity development.METHODSWe retrospectively reviewed all patients with BCR-ABL–positive CML enrolled in this GIPAP program between 2009 and 2018. Clinical data were analyzed using descriptive statistics, Kaplan-Meier methods, proportional hazards regression, and the Kruskal-Wallis test.RESULTSOne hundred twenty-four patients were included. The median age at diagnosis was 34 (range 8-81) years. On imatinib, 91% achieved complete hematologic response (CHR) after a median of 49 days. Seven (6%) and 12 (11%) patients had primary and secondary imatinib resistance, respectively. The 3-year overall survival was 80% (95% CI, 72 to 87) for the cohort, with superior survival in imatinib responders compared with those with primary and secondary resistance. The median time from imatinib initiation to CHR was 59 versus 38 days (P = .040) before and after in-country diagnostic testing, whereas the median time to diagnosis (P = .056) and imatinib initiation (P = .170) was not significantly different.CONCLUSIONCoupling molecular diagnostics with affordable access to imatinib within a comprehensive cancer care delivery program is a successful long-term strategy to treat CML in resource-constrained settings. Our patients are younger and have higher rates of imatinib resistance compared with historic cohorts in high-income countries. High imatinib resistance rates highlight the need for access to molecular monitoring, resistance testing, and second-generation tyrosine kinase inhibitors, as well as systems to support drug adherence. Hematologic response is an accurate resource-adapted predictor of survival in this setting. Local diagnostic capacity development has allowed for continuous, timely CML care delivery in Rwanda.

PURPOSE Hodgkin lymphoma (HL) is highly curable in high-income countries (HICs), yet many patients around the world do not have access to therapy. In 2012, cancer care was established at a rural district hospital in Rwanda through international collaboration, and a treatment protocol using doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) without radiotherapy was implemented. METHODS We conducted a retrospective cohort study of all patients with confirmed HL seen at Butaro Hospital from 2012 to 2018 to evaluate quality indicators and clinical outcomes. RESULTS Eighty-five patients were included (median age, 16.8 years; interquartile range, 11.0-30.5 years). Ten (12%) were HIV positive. Most had B symptoms (70%) and advanced stage (56%) on examination and limited imaging. Of 21 specimens evaluated for Epstein-Barr virus, 14 (67%) were positive. Median time from biopsy to treatment was 6.0 weeks. Of 73 patients who started ABVD, 54 (74%) completed 6 cycles; the leading reasons for discontinuation were treatment abandonment and death. Median dose intensity of ABVD was 92%. Of 77 evaluable patients, 33 (43%) are in clinical remission, 27 (36%) are deceased, and 17 (22%) were lost to follow-up; 3-year survival estimate is 63% (95% CI, 50% to 74%). Poorer performance status, advanced stage, B symptoms, anemia, dose intensity < 85%, and treatment discontinuation were associated with worse survival. CONCLUSION Treating HL with standard chemotherapy in a low-resource setting is feasible. Most patients who completed treatment experienced a clinically significant remission with this approach. Late presentation, treatment abandonment, and loss to follow-up contribute to the discrepancy in survival compared with HICs. A strikingly younger age distribution in our cohort compared with HICs suggests biologic differences and warrants further investigation.

PURPOSEThe burden of cancer is growing in low- and middle-income countries (LMICs), including sub-Saharan Africa. Ensuring the delivery of high-quality cancer care in such regions is a pressing concern. There is a need for strategies to identify meaningful and relevant quality measures that are applicable to and usable for quality measurement and improvement in resource-constrained settings.METHODSTo identify quality measures for breast cancer care at Butaro Cancer Center of Excellence (BCCOE) in Rwanda, we used a modified Delphi process engaging two panels of experts, one with expertise in breast cancer evidence and measures used in high-income countries and one with expertise in cancer care delivery in Rwanda.RESULTSOur systematic review of the literature yielded no publications describing breast cancer quality measures developed in a low-income country, but it did provide 40 quality measures, which we adapted for relevance to our setting. After two surveys, one conference call, and one in-person meeting, 17 measures were identified as relevant to pathology, staging and treatment planning, surgery, chemotherapy, endocrine therapy, palliative care, and retention in care. Successes of the process included participation by a diverse set of global experts and engagement of the BCCOE community in quality measurement and improvement. Anticipated challenges include the need to continually refine these measures as resources, protocols, and measurement capacity rapidly evolve in Rwanda.CONCLUSIONA modified Delphi process engaging both global and local expertise was a promising strategy to identify quality measures for breast cancer in Rwanda. The process and resulting measures may also be relevant for other LMIC cancer facilities. Next steps include validation of these measures in a retrospective cohort of patients with breast cancer.

Sepsis is a major cause of neonatal mortality and children born in low- and middle-income countries (LMICs) are at greater risk of severe neonatal infections than those in higher-income countries. Despite this disparity, there are limited contemporaneous data linking the clinical features of neonatal sepsis with outcome in LMICs. Here, we aimed to identify factors associated with mortality from neonatal sepsis in Vietnam. We conducted a prospective, observational study to describe the clinical features, laboratory characteristics, and mortality rate of neonatal sepsis at a major children's hospital in Ho Chi Minh City. All in-patient neonates clinically diagnosed with probable or culture-confirmed sepsis meeting inclusion criteria from January 2017 to June 2018 were enrolled. We performed univariable analysis and logistic regression to identify factors independently associated with mortality. 524 neonates were recruited. Most cases were defined as late-onset neonatal sepsis and were hospital-acquired (91.4% and 73.3%, respectively). The median (IQR) duration of hospital stay was 23 (13-41) days, 344/524 (65.6%) had a positive blood culture (of which 393 non-contaminant organisms were isolated), and 69/524 (13.2%) patients died. Coagulase-negative staphylococci (232/405; 57.3%), Klebsiella spp. (28/405; 6.9%), and Escherichia coli (27/405; 6.7%) were the most isolated organisms. Sclerema (OR = 11.4), leukopenia 4 mmol/L (OR = 3.4), extremely low birth weight (OR = 3.2), and hyperglycaemia >180 mg/dL (OR = 2.6) were all significantly (p

The regeneration and growth of commercially valuable tree species after selective logging are important for sustainable management of forest. This study compared density of seedlings (height < 2 m), saplings (height ≥ 2 m and diameter at breast height (dbh) < 10 cm) and trees (dbh ≥ 10 cm) of 18 commercially valuable tree species in Vietnam after 30 years of selective logging. Data were collected in high impact (where 30 to less than 50% standing volume was extracted), low impact (less than 30% standing volume was extracted) and unlogged forests. Results indicated that tree density in high impact forest was significantly higher than that in low impact and unlogged forests. Basal areas in high and low impact forests were significantly lower than that in unlogged forest. Density of ≥ 5 cm dbh saplings in high impact forest was significantly higher than that in low impact and unlogged forests. Seedling density in high impact forest was highest between the three forest stands. We concluded that a duration of 30 years was insufficient for logged forests to recover to the status of unlogged forest, regardless of logging intensities. [ABSTRACT FROM AUTHOR]

Sự ức chế ăn mòn của amoxicillin (AMO) trên thép các bon nhẹ trong môi trường HCl 1 M đã được nghiên cứu bằng phương pháp thực nghiệm và hóa tính toán. Hiệu quả ức chế ăn mòn của AMO lên thép tăng lên khi tăng nồng độ AMO và đạt cực đại (84,72%) ở 25 °C và nồng độ AMO 100 mg·L–1. Một vài thông số hóa lượng tử được tính toán dựa trên cấu hình tối ưu của AMO ở mức ở mức lý thuyết B3LYP/6-31+G(d,p). Mô phỏng động lực học phân tử và mô phỏng Monte Carlo được ứng dụng để tìm cấu hình hấp phụ bền nhất của AMO trên bề mặt Fe(110) và làm rõ cơ chế của quá trình ức chế ăn mòn. Kết quả cho thấy AMO là một chất ức chế ăn mòn hiệu quả đối với thép các bon nhẹ trong dung dịch HCl 1 M.