Magnitude and associated factors of intraoperative cardiac complications among geriatric patients who undergo non-cardiac surgery at public hospitals in the southern region of Ethiopia: a multi-center cross-sectional study in 2022/2023.

Background: Intraoperative cardiac complications are a common cause of morbidity and mortality in non-cardiac surgery. The risk of these complications increased with the average age increasing from 65. In a resource-limited setting, including our study area, the magnitude and associated factors of intraoperative cardiac complications have not been adequately investigated. The aim of this study was to assess the magnitude and associated factors of intraoperative cardiac complications among geriatric patients undergoing non-cardiac surgery. Methods: An institutional-based multi-center cross-sectional study was conducted on 304 geriatric patients at governmental hospitals in the southern region of Ethiopia, from 20 March 2022 to 25 August 2022. Data were collected by chart review and patient interviews. Epi Data version 4.6 and SPSS version 25 were used for analysis. The variables that had association (p < 0.25) were considered for multivariable logistic regression. A p value < 0.05 was considered significant for association. Result: The overall prevalence of intraoperative cardiac complications was 24.3%. Preoperative ST-segment elevation adjusted odds ratio (AOR = 2.43, CI =2.06-3.67), history of hypertension (AOR = 3.42, CI =2.02-6.08), intraoperative hypoxia (AOR = 3.5, CI = 2.07-6.23), intraoperative hypotension (AOR = 6.2 9, CI =3.51-10.94), age > 85 years (AOR = 6.01, CI = 5.12-12.21), and anesthesia time > 3 h (AOR =2.27, CI = 2.0.2-18.25) were factors significantly associated with intraoperative cardiac complications. Conclusion: The magnitude of intraoperative cardiac complications was high among geriatric patients who had undergone non-cardiac surgery. The independent risk factors of intraoperative cardiac complications for this population included age > 85, ST-segment elevation, perioperative hypertension (stage 3 with regular treatment), duration of anesthesia >3 h, intraoperative hypoxia, and intraoperative hypotension. Holistic preoperative evaluation, optimization optimal and perioperative care for preventing perioperative risk factors listed above, and knowing all possible risk factors are suggested to reduce the occurrence of complications.

Clinical presentation and management outcome of pediatric intussusception at Wolaita Sodo University Comprehensive Specialized Hospital: a retrospective cross-sectional study.

OBJECTIVE: To assess the pattern of clinical presentations and factors associated with the management outcome of pediatric intussusception among children treated at Wolaita Sodo University Comprehensive Specialized Hospital, Ethiopia. METHODS: This retrospective cross-sectional study included the medical records of 103 children treated for intussusception from 2018 to 2020. The data collected were analyzed using SPSS 25.0 (IBM Corp., Armonk, NY, USA). RESULTS: In total, 84 (81.6%) patients were released with a favorable outcome. Ileocolic intussusception was a positive predictor, with a nine-fold higher likelihood of a favorable outcome than other types of intussusception [adjusted odds ratio (AOR), 9.16; 95% confidence interval (CI), 2.39-21.2]. Additionally, a favorable outcome was three times more likely in patients who did than did not undergo manual reduction (AOR, 3.08; 95% CI, 3.05-5.48). Patients aged <1 year were 96% less likely to have a positive outcome than those aged >4 years (AOR, 0.04; 95% CI, 0.03-0.57). CONCLUSION: Most patients were discharged with favorable outcomes. Having ileocolic intussusception and undergoing manual reduction were associated with significantly more favorable outcomes of pediatric intussusception. Therefore, nonsurgical management such as hydrostatic enema and pneumatic reduction is recommended to reduce hospital discharge of patients with unfavorable outcomes.

Sustainable Management of the African Great Lake Coastal Areas: Motivations and Perspectives of Community Citizen Scientists.

The long-term sustainability of the African Great Lakes is strongly connected to the management and monitoring of their coastal areas. Yet, the communities that live in these areas are rarely involved in monitoring and have limited influence on key management issues. Furthermore, regulatory activities and knowledge sharing in these transnational ecosystems are strongly limited by funding and infrastructure limitations. Citizen science has great potential to advance both scientific and public understanding of the state of the environment. However, there remains a limited understanding of participants' motivations and expectations, especially in developing countries, where citizen science has great potential to complement regulatory monitoring. The present study explores the motivations of citizen scientists in villages along Lake Tanganyika's northern coast and their potential to take a more active role in lake management. Motivations were examined through qualitative interviews, focus groups, and quantitative surveys with 110 citizen scientists and 110 non-citizen scientists from participating villages. Key motivational factors identified were the desire to contribute to scientific research and local knowledge, as well as aspects of financial compensation. The results confirm that participation in citizen science provides many benefits to participants beyond their role as data aggregators and final knowledge users. However, the incentives to participation varied to those typically considered in citizen science programs conducted in developed countries. To create sustainable long-term community based environmental monitoring, these motivations should be incorporated in the program design and participant recruitment.

Microplastics in marine beach and seabed sediments along the coasts of Dar es Salaam and Zanzibar in Tanzania.

Microplastics (MPs) pollution in the marine environment has been one of the biggest challenge in developing countries due to a lack of proper solid waste management strategies. This study reports the distribution and types of MPs in beach and seabed zones of the Dar es Salaam and Zanzibar coasts. A total of 641 MPs were identified across all sites, of which 84 % and 16 % originated from beach and seabed sediments, respectively. Fragment and fibers were the most common types in both seabed and beach zone confirming the secondary sources of the MPs. Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR), revealed four types of polymers with polyethylene (PE) (56%) and polyester (PS) (24 %) being the most common. Microplastics were more abundant on beaches than in seabed zone. A larger abundance of PE and PS reveals a wide range of MPs entering the Ocean.

Microplastics in Marine Nearshore Surface Waters of Dar es Salaam and Zanzibar, East Africa.

Limited information exists on the occurrence of microplastics (MPs) in East African coastal waters. A 300 µm manta net was used to collect surface water from 8 sites in the regions Dar es Salaam (DES) and Zanzibar (ZZ) during low and high tides. DES had a higher (p < 0.05) abundance of MPs than ZZ. Fragments and fibers were the dominant MP types at all sites. The number of fibers was significantly higher (p = 0.002) in DES than in ZZ. MPs were more prevalent during high tide in both DES and ZZ. The MPs within the 2-5 mm size range were identified most often. White and blue MPs were the most common in study sites comprising 45% and 18% of the total MPs respectively. Three polymers polypropylene (PP) high-density polyethylene (HDPE) and low-density polyethylene (LDPE) were identified. The occurrence of MPs in nearshore waters of DES and ZZ is probably due to their proximity to industrial areas, poor solid waste management, and high population pressure.

Community monitoring of coliform pollution in Lake Tanganyika.

Conventional water quality monitoring has been done for decades in Lake Tanganyika, under different national and international programs. However, these projects utilized monitoring approaches, which were temporally limited, labour intensive and costly. This study examines the use of citizen science to monitor the dynamics of coliform concentrations in Lake Tanganyika as a complementary method to statutory and project-focused measurements. Persons in five coastal communities (Kibirizi, Ilagala, Karago, Ujiji and Gombe) were trained and monitored total coliforms, faecal coliforms and turbidity for one year on a monthly basis, in parallel with professional scientists. A standardized and calibrated Secchi tube was used at the same time to determine turbidity. Results indicate that total and faecal coliform concentrations determined by citizen scientists correlated well to those determined by professional scientists. Furthermore, citizen scientist-based turbidity values were shown to provide a potential indicator for high FC and TC concentrations. As a simple tiered approach to identify increased coliform loads, trained local citizen scientists could use low-cost turbidity measurements with follow up sampling and analysis for coliforms, to inform their communities and regulatory bodies of high risk conditions, as well as to validate local mitigation actions. By comparing the spatial and temporal dynamics of coliform concentrations to local conditions of infrastructure, population, precipitation and hydrology in the 15 sites (3 sites per community) over 12 months, potential drivers of coliform pollution in these communities were identified, largely related to precipitation dynamics and the land use.

Assessment of Ecological Risk of Heavy Metals Using Probabilistic Risk Assessment Model (AQUARISK) in Surface Sediments from Wami Estuary, Tanzania.

Total concentrations of As, Cd, Cr, Cu, Pb, and Zn in sediment samples obtained from Wami Estuary in Tanzania were used to generate contaminant probability density distributions and species sensitivity distributions using the AQUARISK model. Results of tier 1 assessment showed that As, Cd, Cr, Pb, and Zn were not of concern as their measured values and the 99th percentile of the fitted distributions were lower than the SQG low-trigger values. However, Cu was identified as of concern in this estuary. According to the Bur III distributional analysis of the exotoxicological data, the estimated percentage of species likely to be affected is 3.4, 79.4, 79.8, 99.9, 98.4, and 98.0 for As, Cd, Cr, Cu, Pb, and Zn, respectively. Lowering of the current median concentrations of metals (Cd, Cr, Cu, Pb, and Zn) is recommended as they exceeded modeled median target sediment concentration to achieve 95% or higher for species protection. With the ongoing increase in anthropogenic activities in the Wami River catchment, the environmental regulatory bodies may use the findings of the present study and augmented with AQUARISK to set discharge standards for various contaminants in order to minimize impacts to the receiving ecosystems.

Devulcanization of ground tire rubber: microwave and thermomechanical approaches.

We devulcanized ground tire rubber (GTR) in a laboratory microwave oven and an internal mixer, measured the soluble content and the cross-link density of the samples, and then used Horikx's analysis. The results showed that microwave treatment caused severe degradation of the polymer chains, while in the case of thermomechanical devulcanization, the selective scission of covalent cross-links is more common. Four devulcanized ground tire rubber (dGTR) samples were chosen for further study and three groups of samples were produced: dGTR samples containing vulcanizing agents and different amounts of paraffin oil (dGTR-based mixtures), natural rubber-based rubber mixtures with different dGTR contents and reference rubber mixtures with dGTR-based mixtures (increased vulcanizing agent contents). Cure characteristics showed a plasticizer-like effect of dGTR. Tensile and tear strength decreased drastically with increasing dGTR content; however, elongation at break values did not follow such a trend. Mechanical properties improved with increased vulcanizing agent contents. The examined properties of the samples improved even further with the use of thermomechanically devulcanized samples. Horikx's analysis showed that this is attributable to moderate polymer chain scission.

Differences in trophic resources and niches of two juvenile predatory species in three Pangani estuarine zones, Tanzania: stomach contents and stable isotope approaches.

BACKGROUND: Estuaries are primary habitats that serve as feeding and nursery grounds for most juvenile marine fish. However, estuaries have been used as fishing grounds by the artisanal fishers in Tanzania. The slow-growing predatory fish at juvenile and sub-adult stages are among the most frequently caught species that functionally enhance multiple linkages of energy pathways within the food web. Stomach contents and stable isotopes (δ13C and δ15N) were used to describe the nutritional sources and trophic niches between the co-existing benthic, predatory species, Carangoides chrysophrys and Epinephelus malabaricus in the Pangani estuary, Tanzania. RESULTS: The findings indicated significant inter-specific variations in dietary composition (PERMANOVA, p = 0.001, pseudo-F = 15.81). The prey-specific index of relative importance (%PSIRI) indicated that juvenile shrimps (%PSIRI = 51.4) and Teleostei (%PSIRI = 26.5) were the main diets of C. chrysophrys while brachyura (%PSIRI = 38.8), juvenile shrimps (%PSIRI = 25.6) and Teleostei (%PSIRI = 23.3) were important diets of E. malabaricus. The isotope mixing models indicated that the predatory fish species accumulate nutrients derived from similar autotrophic sources, microphytobenthos, seagrass and macro-algae via consumption of small fish, including clupeids and mugilids. Yet, they significantly showed different isotopic niche width with varying degree of niche overlap across the longitudinal estuary gradient. This situation was justified by the presence of basal food sources among the estuarine zones that isotopically were different. CONCLUSION: The reliance of both predators on clupeids and mugilid preys that are trophically linked with estuarine and marine basal food sources, is an indication of low estuarine food webs' connectivity to the fresh water related food web. This situation is most likely threatening the stability of the estuarine food web structure. Management strategies and plans in place should be cautiously implemented to ensure the balanced anthropogenic freshwater use in the catchment and fishing activities, for the maintenance of the Pangani estuarine ecosystem health.

Microwave Devulcanized Crumb Rubbers in Polypropylene Based Thermoplastic Dynamic Vulcanizates.

Because of the chemically crosslinked 3D molecular structure of rubbers, their recycling is a challenging task, especially when cost efficiency is also considered. One of the most straightforward procedures is the grinding of discarded rubber products with subsequent devulcanization. The devulcanized rubber can be used as a feedstock for fresh rubber compounds or can be blended with uncured virgin rubber and thermoplastic polymers to form thermoplastic dynamic vulcanizates (TDVs). TDVs combine the beneficial (re)processability of thermoplastics and the elastic properties of rubbers. Our current work focuses on the development of polypropylene (PP)-based TDVs with the use of a tire model rubber (MR) composed of natural rubber (NR) and styrene-butadiene rubber (SBR) in a ratio of 70/30. The research target was the partial substitution of the above fresh MR by microwave devulcanized crumb rubber (dCR). TDVs were produced by continuous extrusion, and the effects of composition (PP/MR/dCR = 40/60/0…50/35/15) and processing parameters (different screw configurations, temperature profiles, the feeding method of PP) were investigated. Results showed that the fresh rubber compound can be replaced up to 10 wt % without compromising the mechanical properties of the resulting TDV.