59 research outputs found
Tropical convective cloud characterization using ground-based microwave radiometric observations
Characterization of the microphysical and thermodynamical properties of convective events over the tropical coastal station Thiruvananthapuram (TVM) has been carried out based on multiyear microwave radiometer profiler observations. The analyses have been extended to develop a methodology to identify convective events, which is based on the radiometric brightness temperature (Tb) difference threshold, at 30 and 22.23 GHz channels, and the results are compared with reflectivity and rainfall intensity deduced from concurrent and collocated disdrometer measurements. Eighty-four of such convections were identified using the aforementioned methodology over the station during 2010-2013, i.e., both for pre- and post-Indian summer monsoon months, and further evaluated by computing their stability indexes. The occurrence of convective systems peaks in the afternoon and early-morning hours with genesis, respectively, over the land and the sea
Nanomaterials for renewable energy storage: synthesis, characterization, and applications
1Department of Chemical and Materials Engineering, King Abdulaziz University, P.O. Box 80204, Jeddah 21589, Saudi Arabia 2Gas Processing Center, College of Engineering, Qatar University, P.O. Box 2713, Doha, Qatar 3Electrochemical Power Systems Division, CSIR-Central Electrochemical Research Institute, Karaikudi 630006, India 4SABIC Chair in Catalysis, King Abdulaziz University, P.O. Box 80204, Jeddah 21589, Saudi Arabia 5Game Lab, Chenergy Group, Department of Applied Science and Technology (DISAT), Politecnico Di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Ital
The rebellious man: next-of-kin accounts of the death of a male relative on antiretroviral therapy in sub-Saharan Africa
The HIV response is hampered by many obstacles to progression along the HIV care cascade, with men, in particular, experiencing different forms of disruption. One group of men, whose stories remain untold, are those who have succumbed to HIV-related illness. In this paper, we explore how next-of-kin account for the death of a male relative. We conducted 26 qualitative after-death interviews with family members of male PLHIV who had recently died from HIV in health and demographic surveillance sites in Malawi, Tanzania, Kenya, Uganda, Zimbabwe and South Africa. The next-of-kin expressed frustration about the defiance of their male relative to disclose his HIV status and ask for support, and attributed this to shame, fear and a lack of self-acceptance of HIV diagnosis. Next-of-kin painted a picture of their male relative as rebellious. Some claimed that their deceased relative deliberately ignored instructions received by the health worker. Others described their male relatives as unable to maintain caring relationships that would avail day-to-day treatment partners, and give purpose to their lives. Through these accounts, next-of-kin vocalised the perceived rebellious behaviour of these men, and in the process of doing so neutralised their responsibility for the premature death of their relative
The interlayer cohesive energy of graphite from thermal desorption of polyaromatic hydrocarbons
We have studied the interaction of polyaromatic hydrocarbons (PAHs) with the
basal plane of graphite using thermal desorption spectroscopy. Desorption
kinetics of benzene, naphthalene, coronene and ovalene at sub-monolayer
coverages yield activation energies of 0.50 eV, 0.85 eV, 1.40 eV and 2.1 eV,
respectively. Benzene and naphthalene follow simple first order desorption
kinetics while coronene and ovalene exhibit fractional order kinetics owing to
the stability of 2-D adsorbate islands up to the desorption temperature.
Pre-exponential frequency factors are found to be in the range
- as obtained from both Falconer--Madix (isothermal
desorption) analysis and Antoine's fit to vapour pressure data. The resulting
binding energy per carbon atom of the PAH is 5 meV and can be identified
with the interlayer cohesive energy of graphite. The resulting cleavage energy
of graphite is ~meV/atom which is considerably larger than previously
reported experimental values.Comment: 8 pages, 4 figures, 2 table
Strong magnon-photon coupling with chip-integrated YIG in the zero-temperature limit
The cross-integration of spin-wave and superconducting technologies is a
promising method for creating novel hybrid devices for future information
processing technologies to store, manipulate, or convert data in both classical
and quantum regimes. Hybrid magnon-polariton systems have been widely studied
using bulk Yttrium Iron Garnet (YFeO, YIG) and
three-dimensional microwave photon cavities. However, limitations in YIG growth
have thus far prevented its incorporation into CMOS compatible technology such
as high quality factor superconducting quantum technology. To overcome this
impediment, we have used Plasma Focused Ion Beam (PFIB) technology -- taking
advantage of precision placement down to the micron-scale -- to integrate YIG
with superconducting microwave devices. Ferromagnetic resonance has been
measured at millikelvin temperatures on PFIB-processed YIG samples using planar
microwave circuits. Furthermore, we demonstrate strong coupling between
superconducting resonator and YIG ferromagnetic resonance modes by maintaining
reasonably low loss while reducing the system down to the micron scale. This
achievement of strong coupling on-chip is a crucial step toward fabrication of
functional hybrid quantum devices that advantage from spin-wave and
superconducting components.Comment: 10 pages, 6 figure
Exploring the effectiveness of the output-based aid voucher program to increase uptake of gender-based violence recovery services in Kenya: a qualitative evaluation
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background: Few studies in Africa have explored in detail the ability of output-based aid (OBA) voucher programs to increase access to gender-based violence recovery (GBVR) services. Methods: A qualitative study was conducted in 2010 and involved: (i) in-depth interviews (IDIs) with health managers, service providers, voucher management agency (VMA) managers and (ii) focus group discussions (FGDs) with voucher users, voucher non-users, voucher distributors and opinion leaders drawn from five program sites in Kenya. Results: The findings showed promising prospects for the uptake of OBA GBVR services among target population. However, a number of factors affect the uptake of the services. These include lack of general awareness of the GBVR services vouchers, lack of understanding of the benefit package, immediate financial needs of survivors, as well as stigma and cultural beliefs that undermine reporting of cases or seeking essential medical services. Moreover, accreditation of only hospitals to offer GBVR services undermines access to the services in rural areas. Poor responsiveness from law enforcement agencies and fear of reprisal from perpetrators also undermine treatment options and access to medical services. Low provider knowledge on GBVR services and lack of supplies also affect effective provision and management of GBVR services. Conclusions: The above findings suggest that there is a need to build the capacity of health care providers and police officers, strengthen the community strategy component of the OBA program to promote the GBVR services voucher, and conduct widespread community education programs aimed at prevention, ensuring survivors know how and where to access services and addressing stigma and cultural barriers.The Bill and Melinda Gates Foundatio
Multiple Sexual Partners and Condom use among 10 - 19 Year-olds in four Districts in Tanzania: What do we Learn?
Although some studies in Tanzania have addressed the question of sexuality and STIs among adolescents, mostly those aged 15 - 19 years, evidence on how multiple sexual partners influence condom use among 10 - 19 year-olds is limited. This study attempts to bridge this gap by testing a hypothesis that sexual relationships with multiple partners in the age group 10 - 19 years spurs condom use during sex in four districts in Tanzania. Secondary analysis was performed using data from the Adolescents Module of the cross-sectional household survey on Maternal, Newborn and Child Health (MNCH) that was done in Kigoma, Kilombero, Rufiji and Ulanga districts, Tanzania in 2008. A total of 612 adolescents resulting from a random sample of 1200 households participated in this study. Pearson Chi-Square was used as a test of association between multiple sexual partners and condom use. Multivariate logistic regression model was fitted to the data to assess the effect of multiple sexual partners on condom use, having adjusted for potential confounding variables. STATA (10) statistical software was used to carry out this process at 5% two-sided significance level. Of the 612 adolescents interviewed, 23.4% reported being sexually active and 42.0% of these reported having had multiple (> 1) sexual partners in the last 12 months. The overall prevalence of condom use among them was 39.2%. The proportion using a condom at the last sexual intercourse was higher among those who knew that they can get a condom if they want than those who did not. No evidence of association was found between multiple sexual partners and condom use (OR = 0.77, 95% CI = 0.35 - 1.67, P = 0.504). With younger adolescents (10 - 14 years) being a reference, condom use was associated with age group (15 - 19: OR = 3.69, 95% CI = 1.21 - 11.25, P = 0.022) and district of residence (Kigoma: OR = 7.45, 95% CI = 1.79 - 31.06, P = 0.006; Kilombero: OR = 8.89, 95% CI = 2.91 - 27.21, P < 0.001; Ulanga: OR = 5.88, 95% CI = 2.00 - 17.31, P = 0.001), Rufiji being a reference category. No evidence of association was found between multiple sexual partners and condom use among adolescents in the study area. The large proportion of adolescents who engage in sexual activity without using condoms, even those with multiple partners, perpetuates the risk of transmission of HIV infections in the community. Strategies such as sex education and easing access to and making a friendly environment for condom availability are important to address the risky sexual behaviour among adolescents
Male engagement guidelines in antenatal care: unintended consequences for pregnant women in Tanzania.
BACKGROUND: The meaningful engagement of male partners in antenatal care (ANC) can positively impact maternal and newborn health outcomes. The Tanzania National Plan for the Elimination of Mother to Child Transmission of HIV recommends male partners attend the first ANC appointment as a strategy for HIV prevention and treatment. This recommendation seeks to increase uptake of HIV and reproductive healthcare services, but unintended consequences of these guidelines may negatively impact women's ANC experiences. This study qualitatively examined the impact of policy promoting male engagement on women's ANC experiences. METHODS: The study was conducted in two urban clinics in Kilimanjaro Region, Tanzania. In-depth interviews were conducted with 19 participants (13 women and 6 male partners) attending a first ANC appointment. A semi-structured guide was developed, applying Kabeer's Social Relations Approach. Data were analyzed using applied thematic analysis, combining memo writing, coding, synthesis, and comparison of themes. RESULTS: Male attendance impacted the timing of women's presentation to ANC and experience during the first ANC visit. Women whose partners could not attend delayed their presentation to first ANC due to fears of being interrogated or denied care because of their partner absence. Women presenting with partners were given preferential treatment by clinic staff, and women without partners felt discriminated against. Women perceived that the clinic prioritized men's HIV testing over involvement in pregnancy care. CONCLUSIONS: Study findings indicate the need to better assess and understand the unintended impact of policies promoting male partner attendance at ANC. Although male engagement can benefit the health outcomes of mothers and newborn children, our findings demonstrate the need for improved methods of engaging men in ANC. ANC clinics should identify ways to make clinic settings more male friendly, utilize male attendance as an opportunity to educate and engage men in pregnancy and newborn care. At the same time, clinic policies should be cognizant to not discriminate against women presenting without a partner
Evaluation of knowledge levels amongst village AIDS committees after undergoing HIV educational sessions: results from a pilot study in rural Tanzania
ABSTRACT:
BACKGROUND:
Village AIDS committees (VAC) were formed by the Tanzanian government in 2003 to provide HIV education to their communities. However, their potential has not been realised due to their limited knowledge and misconceptions surrounding HIV, which could be addressed through training of VAC members. In an attempt to increase HIV knowledge levels and address common misconceptions amongst the VACs, an HIV curriculum was delivered to members in rural north western Tanzania.
METHODS:
An evaluation of HIV knowledge was conducted prior to and post-delivery of HIV training sessions, within members of three VACs in Kisesa ward. Quantitative surveys were used with several open-ended questions to identify local misconceptions and evaluate HIV knowledge levels. Short educational training sessions covering HIV transmission, prevention and treatment were conducted, with each VAC using quizzes, role-plays and participatory learning and action tools. Post-training surveys occurred up to seven days after the final training session.
RESULTS:
Before the training, "good" HIV knowledge was higher amongst men than women (p = 0.041), and among those with previous HIV education (p = 0.002). The trade-centre had a faster turn-over of VAC members, and proximity to the trade-centre was associated with a shorter time on the committee.Training improved HIV knowledge levels with more members achieving a "good" score in the post-training survey compared with the baseline survey (p = < 0.001). The training programme was popular, with 100% of participants requesting further HIV training in the future and 51.7% requesting training at three-monthly intervals.
CONCLUSIONS:
In this setting, a series of HIV training sessions for VACs demonstrated encouraging results, with increased HIV knowledge levels following short educational sessions. Further work is required to assess the success of VAC members in disseminating this HIV education to their communities, as well as up-scaling this pilot study to other regions in Tanzania with different misconceptions
Novel Lobophorins Inhibit Oral Cancer Cell Growth and Induce Atf4- and Chop-Dependent Cell Death in Murine Fibroblasts
As part of the International Cooperative Biodiversity Groups (ICBG) Program, we were interested in identifying biologically active unfolded protein response (UPR) inducing compounds from marine microorganisms isolated from Costa Rican biota. With this aim in mind we have now generated more than 33,000 unique prefractionated natural product extracts from marine and terrestrial organisms that have been submitted to the Center of Chemical Genomics (CCG) at the University of Michigan for high throughput screening (HTS). An effective complementary cell-based assay to identify novel modulators of UPR signaling was used for screening extracts. Active fractions were iteratively subjected to reverse-phase HPLC chromatographic analysis, and together with lobophorin A, B, E, and F (1–4), three new lobophorin congeners, designated as CR1 (5), CR2 (6), and CR3 (7) were isolated. Herein, we report that secondary assays revealed that the new lobophorins induced UPR-associated gene expression, inhibited oral squamous cell carcinoma cell growth, and led to UPR-dependent cell death in murine embryonic fibroblast (MEF) cells.International Cooperative Biodiversity Groups/[U01 TW007404]/ICBG/Estados UnidosNational Institutes of Health/[DK042394]/NIH/Estados UnidosNational Institutes of Health/[DK088227]/NIH/Estados UnidosNational Institutes of Health/[HL052173]/NIH/Estados UnidosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones en Productos Naturales (CIPRONA)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Químic
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