1,052 research outputs found
Risk Factors of Deep Venous Thrombosis in Duplex and Colour Doppler Ultrasound at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia
Background: Deep venous thrombosis is a major health problem with high morbidity and mortality worldwide. Thus early, correct and definitive diagnosis is crucial in assessing thromboembolic risk and initiating therapy. In this regard Patients at risk must be identified and given appropriate prophylaxis to reduce Venous Thromboembolism related morbidity and mortality.The main objective of this study was to determine common risk factors of deep venous thrombosis (DVT) and the common sites involved by DVT in ultrasound proven cases.Methods: This was a prospective cross-sectional study which included all patients who had proven deep venous thrombosis by Dopper and duplex ultrasound at Tikur Anbessa Specialized Hospital (TASH). Senior radiology residents collected the data after getting approval from consultant radiologists. Analysis was under taken by principal investigator.Results: There were a total 81 ultrasound proven cases of DVT involving the extremities during the study period out of which 34.6% were males and 65.4% females. The majority (58%) were under the age of 40 years. Malignancy was the most common identified risk factor (30.9% of the cases) followed by prolonged immobilization 19.8%, pregnancy related problems 6.2% and severe trauma 6.2% of the patients. No apparent risk factor was found in 12.3%. Swelling was noted in 93.8% of the participants in combination with other manifestations or alone; whereas pain was noted in 70.4% of the patients. The study showed 59.3% had involvement of the left lower limb only; 11.1% had involvement of both lower limbs. The upper extremities were affected in only one patient having bilateral involvement of brachiocephalic veins. According to the study 84% of the patients had combined involvement of the deep veins of the lower extremities extending from the common iliac veins to the poplitial veins. The study revealed that 28.4% of participants were found to havecombined involvement of the common femoral vein (CFV), superficial femoral vein (SFV) & poplitial vein; 22.2% had combined involvement of the CFV & SFV. Conclusion: From the study we concluded that Malignancy, prolonged immobilization, pregnancy related problems and major trauma were the most common risk factors noted for DVT and Swelling was the most common presenting manifestation. Majority of the patients had multiple site deep vein involvement extending from the common iliac to the poplitial veins.Key words: Risk, Factors, Deep, Vein, Thrombosis, Duplex,Doppler
Extending Adjuvant Endocrine Therapy for 10 Years: A Mixed-Methods Analysis of Women's Decision Making in an Online Breast Cancer Forum
An additional 5 years of treatment with adjuvant hormonal therapy, to complete 10 years of medication, is recommended to reduce the risk of breast cancer recurrence. Yet professionals and patients should balance this benefit against side effects and toxicities. Little is known about women's decision making regarding persistence with extended endocrine therapy. In this study, we collected data from a UK online breast cancer forum to analyse patterns of persistence and its associated factors. A mixed-methods exploratory sequential design was used, with a qualitative analysis of text (n = 61 individuals) informing the development of a quantitative instrument to statistically analyse the prevalence of the findings (n = 130). Our findings identified three different groups of women who had to make decisions regarding persistence with treatment: those about to complete 5 years of therapy, those who decided to extend treatment, and those who were initially prescribed 10 years. Factors affecting persistence were, lack of self-efficacy in managing side effects, lack of reassurance about individual risk of recurrence, and impact on quality of life. Interventions such as training of healthcare professionals including risk communication, medication reviews by clinical pharmacists, and re-planning of services in follow-up care, should better support women's needs in extended hormonal therapy
High-Responsivity Graphene-Boron Nitride Photodetector and Autocorrelator in a Silicon Photonic Integrated Circuit
Graphene and other two-dimensional (2D) materials have emerged as promising
materials for broadband and ultrafast photodetection and optical modulation.
These optoelectronic capabilities can augment complementary
metal-oxide-semiconductor (CMOS) devices for high-speed and low-power optical
interconnects. Here, we demonstrate an on-chip ultrafast photodetector based on
a two-dimensional heterostructure consisting of high-quality graphene
encapsulated in hexagonal boron nitride. Coupled to the optical mode of a
silicon waveguide, this 2D heterostructure-based photodetector exhibits a
maximum responsivity of 0.36 A/W and high-speed operation with a 3 dB cut-off
at 42 GHz. From photocurrent measurements as a function of the top-gate and
source-drain voltages, we conclude that the photoresponse is consistent with
hot electron mediated effects. At moderate peak powers above 50 mW, we observe
a saturating photocurrent consistent with the mechanisms of electron-phonon
supercollision cooling. This nonlinear photoresponse enables optical on-chip
autocorrelation measurements with picosecond-scale timing resolution and
exceptionally low peak powers
Factors associated with the performance and cost-effectiveness of using lymphatic filariasis transmission assessment surveys for monitoring soil-transmitted helminths: a case study in Kenya.
Transmission assessment surveys (TAS) for lymphatic filariasis have been proposed as a platform to assess the impact of mass drug administration (MDA) on soil-transmitted helminths (STHs). This study used computer simulation and field data from pre- and post-MDA settings across Kenya to evaluate the performance and cost-effectiveness of the TAS design for STH assessment compared with alternative survey designs. Variations in the TAS design and different sample sizes and diagnostic methods were also evaluated. The district-level TAS design correctly classified more districts compared with standard STH designs in pre-MDA settings. Aggregating districts into larger evaluation units in a TAS design decreased performance, whereas age group sampled and sample size had minimal impact. The low diagnostic sensitivity of Kato-Katz and mini-FLOTAC methods was found to increase misclassification. We recommend using a district-level TAS among children 8-10 years of age to assess STH but suggest that key consideration is given to evaluation unit size
Men's involvement in family planning service utilization among married men in Kondala district, western Ethiopia: a community-based comparative cross-sectional study.
BACKGROUND: Men involvement is one of the important factors in family planning (FP) service utilization. Their limitation in the family planning program causes a decrease in service utilization as well as the discontinuation of the method which eventually leads to failure of the program. Family planning uptake is low but there is no enough study conducted on the parameters of husband involvement in Ethiopia. Hence, this study focused to assess men's involvement in family planning service utilization in Kondala district, western Ethiopia. METHODS: Community based comparative cross-sectional study design was employed in urban and rural kebeles of kondala district using quantitative and qualitative data collection tools. The multi-stage sampling method was employed to select 370 participants from each of the four urban and eight rural kebeles. Logistic regression analysis was used to identify variables that affect husbands' involvement in FP service utilization. Statistical significance was declared at p-value of < 0.05 with 95% confidence interval (CI) and strength of association was reported by odds ratio (OR). RESULTS: The study showed that 203(55.6%) men from urban and 178(48.8%) from rural were involved in FP service utilization. The median age of the respondents was 36+ 8.5 years (IQR: 27.5-44.5) in urban and 35 years (IQR: 25-45) in rural parts. Respondents who had four and above current children (AOR = 3.25, 95%CI = 1.51-7.02) in urban and (AOR = 4.20, 95%CI = 1.80-9.79) in rural were positively associated with men's involvement in FP service utilization. In the urban setting, being government employee (AOR = 2.58, 95%CI = 1.25-5.33), wishing less than two children (AOR = 3.08, 95%CI = 1.80-5.24) and having a better attitude towards FP methods (AOR = 1.86, 95%CI = 1.16-2.99) were positively associated with FP service utilization. While good educational background (AOR = 2.13, 95%CI = 1.02-4.44), short distance from home to health facility (AOR = 2.29, 95%CI = 1.24-4.19) and having better knowledge (AOR = 4.49, 95%CI = 2.72-7.38) were positively associated with men involvement in FP service utilization in the rural area. CONCLUSION: Low involvement of men in family planning service utilization was reported in both settings. Factors associated with husbands' involvement were varied between the two setups, except for the current number of children. Future FP program should incorporate infrastructure associated with the health facility, knowledge, and attitudinal factors
A Modeling Approach to Determine the Impacts of Land Use and Climate Change Scenarios on the Water Flux of the Upper Mara River
With the flow of the Mara River becoming increasingly erratic especially in the upper reaches, attention has been directed to land use change as the major cause of this problem. The semi-distributed hydrological model Soil and Water Assessment Tool 5 (SWAT) and Landsat imagery were utilized in the upper Mara River Basin in order to 1) map existing field scale land use practices in order to determine their impact 2) determine the impacts of land use change on water flux; and 3) determine the impacts of rainfall (0%, ±10% and ±20%) and air temperature variations (0% and +5%) based on the Intergovernmental Panel on Climate Change projections on the water flux of the 10 upper Mara River. This study found that the different scenarios impacted on the water balance components differently. Land use changes resulted in a slightly more erratic discharge while rainfall and air temperature changes had a more predictable impact on the discharge and water balance components. These findings demonstrate that the model results 15 show the flow was more sensitive to the rainfall changes than land use changes. It was also shown that land use changes can reduce dry season flow which is the most important problem in the basin. The model shows also deforestation in the Mau Forest increased the peak flows which can also lead to high sediment loading in the Mara River. The effect of the land use and climate change scenarios on the sediment and 20 water quality of the river needs a thorough understanding of the sediment transport processes in addition to observed sediment and water quality data for validation of modeling results
Conservation agriculture with drip irrigation: Effects on soil quality and crop yield in sub-Saharan Africa
The traditional agriculture production system in sub-Saharan Africa (SSA) caused significant soil erosion and degradation of soil quality. In addition, dependability of rainfall for irrigation needs limits the crop production. Advanced agricultural practices are thus needed at the local level to sustain the livelihood of smallholder farmers in the region. In this study, conservation agriculture (CA) practice with drip irrigation technology was compared (using field experiments and watershed modeling) with the traditional conventional tillage (CT) practice for its potential in improving soil quality and crop productivity in the region. Biophysical data were collected (2015 to 2017) from a total of 43 paired plots (CA and CT) at four study sites in SSA: Dangishita and Robit in Ethiopia, Yemu in Ghana, and Mkindo in Tanzania. The Agricultural Policy/Environmental eXtender (APEX) model was calibrated and validated with reasonable efficiency in simulating crop yields for both CA and CT practices; average PBIAS ≤±12% and ≤±11%, for CA and CT. The impact of the CA system on soil quality (soil carbon [C] and nitrogen [N]) was analyzed based on the well-tested model prediction results. The total C and N were increased under CA across the study sites on average by 6% and 4.1%, when compared to CT over the study period. Both the experiment and model prediction showed that crop yield was significantly improved by CA—on average 37.4% increases across the sites when compared to CT. Conservation agriculture with drip irrigation was an efficient local strategy to improve crop production in the region while enhancing the ecosyste
Brucellosis in ruminants and pastoralists in Borena, Southern Ethiopia
Funder: Biotechnology and Biological Sciences Research Council; funder-id: http://dx.doi.org/10.13039/501100000268; Grant(s): ref: BB/L018977/1Brucellosis is a bacterial zoonotic disease that has important veterinary and public health consequences as well as economic impact in sub Saharan Africa including Ethiopia. A cross-sectional study was conducted in four selected districts of Borena Pastoral setting in Southern Ethiopia from October 2017 to February 2018 to estimate the prevalence of brucellosis and assess associated risk factors in cattle, sheep, goats and occupationally associated humans. A total of 750 cattle, 882 sheep and goats and 341 human subjects were screened for evidence of brucellosis using the Rose Bengal Test (RBT) with positive results confirmed by Competitive-ELISA(c-ELISA). Structured questionnaires were used for collection of metadata from individual animals, herders and animal attendants to test the association between explanatory and outcome variables. The overall animal level prevalence was 2.4% (95% confidence interval, CI: 1.4–3.7) in cattle, 3.2% (95% CI: 2.1–4.6) in sheep and goats, and 2.6% (95% CI: 1.2–5) in humans occupationally linked to livestock production systems. Herd size, parity, and history of abortion were risk factors associated with Brucella seropositivity (P<0.05) in cattle whereas in sheep and goats the results showed that district, age group, flock size, and history of abortion were significantly associated risk factors with Brucella seropositivity (P<0.05). Assisting calving and presence of seropositive animals in a household (P<0.05) were significantly associated with Brucella seropositivity in humans. Evidence of brucellosis in various animal species and the associated human population illustrates the need for a coordinated One Health approach to controlling brucellosis so as to improve public health and livestock productivity
Three-dimensional coherent X-ray diffraction imaging via deep convolutional neural networks
As a critical component of coherent X-ray diffraction imaging (CDI), phase retrieval has been extensively applied in X-ray structural science to recover the 3D morphological information inside measured particles. Despite meeting all the oversampling requirements of Sayre and Shannon, current phase retrieval approaches still have trouble achieving a unique inversion of experimental data in the presence of noise. Here, we propose to overcome this limitation by incorporating a 3D Machine Learning (ML) model combining (optional) supervised learning with transfer learning. The trained ML model can rapidly provide an immediate result with high accuracy which could benefit real-time experiments, and the predicted result can be further refined with transfer learning. More significantly, the proposed ML model can be used without any prior training to learn the missing phases of an image based on minimization of an appropriate ‘loss function’ alone. We demonstrate significantly improved performance with experimental Bragg CDI data over traditional iterative phase retrieval algorithms
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