Epanchin P.N.,University of California at Davis |
Epanchin P.N.,University of California at Berkeley |
Knapp R.A.,University of the Sierra |
Lawler S.P.,University of California at Davis
Ecology | Year: 2010
Adjacent food webs may be linked by cross-boundary subsidies: moreproductive donor systems can subsidize consumers in less-productive neighboring recipient systems. Introduced species are known to have direct effects on organisms within invaded communities. However, few studies have addressed the indirect effects of nonnative species in donor systems on organisms in recipient systems. We studied the direct role of introduced trout in altering a lake-derived resource subsidy and their indirect effects in altering a passerine bird's response to that subsidy. We compared the abundance of aquatic insects and foraging Gray-crowned Rosy-Finches (Leucosticte tephrocotis dawsoni, "Rosy-Finch") at fishcontaining vs. fishless lakes in the Sierra Nevada Mountains of California (USA). Introduced trout outcompeted Rosy-Finches for emerging aquatic insects (i.e., mayflies). Fish-containing lakes had 98% fewer mayflies than did fishless lakes. In lakes without fish, Rosy-Finches showed an aggregative response to emerging aquatic insects with 5.9 times more Rosy-Finches at fishless lakes than at fish-containing lakes. Therefore, the introduction of nonnative fish into the donor system reduced both the magnitude of the resource subsidy and the strength of cross-boundary trophic interactions. Importantly, the timing of the subsidy occurs when Rosy-Finches feed their young. If Rosy-Finches rely on aquatic-insect subsidies to fledge their young, reductions in the subsidy by introduced trout may have decreased Rosy-Finch abundances from historic levels. We recommend that terrestrial recipients of aquatic subsidies be included in conservation and restoration plans for ecosystems with alpine lakes. © 2010 by the Ecological Society of America.
Groen R.S.,OverSeas |
Groen R.S.,Johns Hopkins Hospital |
Groen R.S.,Royal Tropical Institute |
Stewart K.-A.,Stanford University |
And 7 more authors.
The Lancet | Year: 2012
Background Surgical care is increasingly recognised as an important part of global health yet data for the burden of surgical disease are scarce. The Surgeons OverSeas Assessment of Surgical Need (SOSAS) was developed to measure the prevalence of surgical conditions and surgically treatable deaths in low-income and middle-income countries. We administered this survey countrywide in Sierra Leone, which ranks 180 of the 187 nations on the UN Development Index. Methods The study was done between Jan 9 and Feb 3, 2012. 75 of 9671 enumeration areas, the smallest administrative units in Sierra Leone, were randomly selected for the study clusters, with a probability proportional to the population size. In each cluster 25 households were randomly selected to take part in the survey. Data were collected via handheld tablets by trained local medical and nursing students. A household representative was interviewed to establish the number of household members (defined as those who ate from the same pot and slept in the same structure the night before the interview), identify deaths in the household during the previous year, and establish whether any of the deceased household members had a condition needing surgery in the week before death. Two randomly selected household members underwent a head-to-toe verbal examination and need for surgical care was recorded on the basis of the response to whether they had a condition that they believed needed surgical assessment or care. Findings Of the 1875 targeted households, data were analysed for 1843 (98%). 896 of 3645 (25%; 95% CI 22 · 9-26 · 2) respondents reported a surgical condition needing attention and 179 of 709 (25%; 95% CI 22 · 5-27 · 9) deaths of household members in the previous year might have been averted by timely surgical care. Interpretation Our results show a large unmet need for surgical consultations in Sierra Leone and provide a baseline against which future surgical programmes can be measured. Additional surveys in other low-income and middle-income countries are needed to document and confirm what seems to be a neglected component of global health.
Kingham T.P.,Sloan Kettering Cancer Center |
Alatise O.I.,Obafemi Awolowo University |
Vanderpuye V.,Korle Bu Teaching Hospital |
Casper C.,Fred Hutchinson Cancer Research Center |
And 6 more authors.
The Lancet Oncology | Year: 2013
Cancer is rapidly becoming a public health crisis in low-income and middle-income countries. In sub-Saharan Africa, patients often present with advanced disease. Little health-care infrastructure exists, and few personnel are available for the care of patients. Surgeons are often central to cancer care in the region, since they can be the only physician a patient sees for diagnosis, treatment (including chemotherapy), and palliative care. Poor access to surgical care is a major impediment to cancer care in sub-Saharan Africa. Additional obstacles include the cost of oncological care, poor infrastructure, and the scarcity of medical oncologists, pathologists, radiation oncologists, and other health-care workers who are needed for cancer care. We describe treatment options for patients with cancer in sub-Saharan Africa, with a focus on the role of surgery in relation to medical and radiation oncology, and argue that surgery must be included in public health efforts to improve cancer care in the region. © 2013 Elsevier Ltd.
Ali D.B.,University of the Sierra |
Tomek M.,Foundation Medicine |
Lisk D.R.,University of the Sierra
Epilepsy and Behavior | Year: 2014
Epilepsy is associated with a significant burden of false beliefs and social stigma in the setting of Sub-Saharan Africa. To assess the impacts of epilepsy on child education in Sierra Leone (SL), we carried out a cross-sectional descriptive study examining its effects on school attendance, participation in physical activities, and social acceptance among classmates. We also assessed the knowledge, beliefs, and attitudes regarding epilepsy of both the children's caregivers and teachers. The data were collected at various epilepsy clinics and schools in Freetown, SL. A total of 50 patients were interviewed and questionnaires administered to their caregivers and teachers, making a total of 150 respondents. Fifty-one percent of the children were absent from school for > 5 days per month. Ninety percent did not participate in games and sports, with the commonest reason being fear of occurrence of seizures. Thirty-six percent claimed having experienced negative attitude from their classmates. Regarding the caregivers, 48% believed that epilepsy was a medical illness, while 34% considered it a demonic manifestation. Forty-eight percent were apprehensive about sending their children to school, with 83% of these caregivers stating fear of seizures and potential injuries. Only 8% of the caregivers did not prevent their children from taking part in any physical activity at school. Regarding the teachers, 16% believed that epilepsy was a demonic manifestation, and 10% thought that it was contagious. Fourteen percent did not think that children with epilepsy should go to school, and 80% would prevent children with epilepsy from participating in games and sports. When faced with a child having a seizure, 48% would hold the child down, 12% would place a hard object in the child's mouth, and 12% would avoid any physical contact. In total, 20% of the children ceased attending school permanently; daily occurrence of seizures (p < 0.05), negative attitude of classmates (p < 0.001), and having an illiterate caregiver (p < 0.02) all showed a significant association with permanent cessation of schooling. The study demonstrates significant negative impacts of epilepsy on child education. Notably, the reasons for permanent exclusion from school appear to be as much related to attitudes as to the medical aspects of the disease itself. The data thus highlight the need for educational programs to address the widely prevalent misconceptions among both caregivers and teachers. © 2014 Elsevier Inc.
Bertone M.P.,London School of Hygiene and Tropical Medicine |
Samai M.,University of the Sierra |
Edem-Hotah J.,University of the Sierra |
Witter S.,Queen Margaret University
Conflict and Health | Year: 2014
Background: It is recognized that decisions taken in the early recovery period may affect the development of health systems. Additionally, some suggest that the immediate post-conflict period may allow for the opening of a political 'window of opportunity' for reform. For these reasons, it is useful to reflect on the policy space that exists in this period, by what it is shaped, how decisions are made, and what are their long-term implications. Examining the policy trajectory and its determinants can be helpful to explore the specific features of the post-conflict policy-making environment. With this aim, the study looks at the development of policies on human resources for health (HRH) in Sierra Leone over the decade after the conflict (2002-2012). Methods. Multiple sources were used to collect qualitative data on the period between 2002 and 2012: a stakeholder mapping workshop, a document review and a series of key informant interviews. The analysis draws from political economy and policy analysis tools, focusing on the drivers of reform, the processes, the contextual features, and the actors and agendas. Findings. Our findings identify three stages of policy-making. At first characterized by political uncertainty, incremental policies and stop-gap measures, the context substantially changed in 2009. The launch of the Free Health Care Initiative provided to be an instrumental event and catalyst for health system, and HRH, reform. However, after the launch of the initiative, the pace of HRH decision-making again slowed down. Conclusions: Our study identifies the key drivers of HRH policy trajectory in Sierra Leone: (i) the political situation, at first uncertain and later on more defined; (ii) the availability of funding and the stances of agencies providing such funds; (iii) the sense of need for radical change - which is perhaps the only element related to the post-conflict setting. It also emerges that a 'windows of opportunity' for reform did not open in the immediate post-conflict, but rather 8 years later when the Free Health Care Initiative was announced, thus making it difficult to link it directly to the features of the post-conflict policy-making environment. © 2014 Bertone et al.; licensee BioMed Central Ltd.
Maconachie R.,University of Bath |
Binns T.,University of Otago |
Tengbe P.,University of the Sierra
Cities | Year: 2012
As skyrocketing global food and energy prices have recently triggered a stream of riots in urban centres across sub-Saharan Africa, underscoring the desperation of urban residents as food becomes unobtainable, cities in the West African country of Sierra Leone face a series of new challenges as the country emerges from a decade of civil war during the 1990s. Focusing on the question of urban food security in and around Sierra Leone's capital city, Freetown, this paper explores the proliferation of urban and peri-urban agriculture (UPA) as a response to the rising demand for food and employment. In this context, the paper examines a recent upsurge in cooperative activity associated with UPA in Freetown, drawing upon the knowledge and perceptions of those involved in urban farming associations. In seeking to better understand the associational and livelihood strategies of urban residents in the post-war era, the paper highlights how UPA activities are currently driving a resurgence in community-based cooperation, a development which could play an important role in safeguarding livelihoods and urban food security during a particularly critical point in the country's post-conflict recovery trajectory. © 2011 Elsevier Ltd.
Zhou H.,University of South Carolina |
Hanson T.,University of South Carolina |
Knapp R.,University of the Sierra
Biometrics | Year: 2015
The global emergence of Batrachochytrium dendrobatidis (Bd) has caused the extinction of hundreds of amphibian species worldwide. It has become increasingly important to be able to precisely predict time to Bd arrival in a population. The data analyzed herein present a unique challenge in terms of modeling because there is a strong spatial component to Bd arrival time and the traditional proportional hazards assumption is grossly violated. To address these concerns, we develop a novel marginal Bayesian nonparametric survival model for spatially correlated right-censored data. This class of models assumes that the logarithm of survival times marginally follow a mixture of normal densities with a linear-dependent Dirichlet process prior as the random mixing measure, and their joint distribution is induced by a Gaussian copula model with a spatial correlation structure. To invert high-dimensional spatial correlation matrices, we adopt a full-scale approximation that can capture both large- and small-scale spatial dependence. An efficient Markov chain Monte Carlo algorithm with delayed rejection is proposed for posterior computation, and an R package spBayesSurv is provided to fit the model. This approach is first evaluated through simulations, then applied to threatened frog populations in Sequoia-Kings Canyon National Park. © 2015, The International Biometric Society.
Murphy L.M.,University of the Sierra
Violence and Victims | Year: 2011
Using a nationally representative sample of participants, this study investigates childhood victimization in the home and adolescent violent victimization in the community on the risk of being a victim of intimate partner violence (IPV), general violence, or both during early adulthood. The study findings indicate being left home alone and being physically abused during childhood, and adolescent violent victimization in the community had strong independent effects on an individual's likelihood of becoming a victim of IPV, general violence, or both in early adulthood. The study findings suggest a consistent pattern of victimization across the life course, and intervention programs need to be developed that address the specific needs of children and adolescents at high risk for home and community violent victimization. © 2011 Springer Publishing Company.
Sesay M.,Shenzhen University |
Sesay M.,University of the Sierra |
Jin X.,Shenzhen University |
Ouyang Z.,Shenzhen University
Journal of the Optical Society of America B: Optical Physics | Year: 2013
In this paper, we design a polarization splitter by combining a photonic crystal waveguide and internal polarization- selective rods leading to a spatial separation of two orthogonal polarizations for mid-infrared applications. The performance of the splitter is investigated by tuning the length of the polarization-selection rods or defect rods for both the polarization extinction ratio (PER) and degree of polarization (DoP). At optimized parameter of the selective rods, the DoP obtained a high value as 1 and the PER obtained a higher value greater than 30 dB for both TE- and TM-polarized lights. © 2013 Optical Society of America.
James P.B.,University of the Sierra |
Bah A.J.,University of the Sierra
BMC Complementary and Alternative Medicine | Year: 2014
Background: The widespread use of CAM around the world requires health professionals including pharmacists to have the required knowledge to better advise their patients. This has lead to an increased need for the inclusion of CAM instruction into the mainstream undergraduate Pharmacy education. This study was designed to describe pharmacy students awareness, use, attitude and perceived need for CAM education at COMAHS-USL and at the same time, determine how these descriptive outcomes are influenced by the socio-demographic variables considered in this study. Methods: A descriptive cross-sectional survey was conducted among undergraduate pharmacy students (n = 90) at the College of Medicine and Allied Health Sciences, University of Sierra Leone using a structured questionnaire. Chi square, fisher exact test, and general linear model univariate analysis were used to compare data between independent cohorts. Results: All 90 (100%) of the students were aware and have used (except Ayurveda) at least one of the listed CAM modalities. Herbal/Botanical/Supplements followed by Spirituality/Prayer were the most commonly known and used CAM modalities. Almost two thirds of students considered the CAM modalities they have used to be effective and not harmful. Overall, pharmacy students had a positive attitude towards CAM (Mean attitudinal score = 34.9 ± 4. 5 (range 19-43)) with fourth and fifth year students showing a significantly less positive attitude as compared to the first, second and third year (B = -3.203 p = 0.001, 95% confidence interval - 5.093 to -1.314). The media [53 (58.9%)] was the most frequent source of information about CAM. Nearly all students [89 (98.9%)] agreed that CAM knowledge is important to them as future pharmacist and that CAM should be included into the Pharmacy curriculum at COMAHS-USL [81 (90.0%)]. Conclusion: Pharmacy students in Sierra Leone are aware of and have used at least one of the CAM modalities and do show a positive attitude towards CAM. This was demonstrated by their overwhelming endorsement for CAM course to be part of the undergraduate pharmacy training at COMAHS-USL. This study among others will inform and guide the development and implementation of CAM instruction at COMAHS-USL.