1,085 research outputs found
Recent research in the African Great Lakes: fisheries, biodiversity and cichlid evolution
The East African Great Lakes are now well known for (1) their fisheries, of vital importance for their rapidly rising riparian human populations, and (2) as biodiversity hotspots with spectacular endemic faunas, of which the flocks of cichlid fishes unique to each of the three largest lakes, Tanganyika, Malawi and Victoria, offer unique opportunities to investigate how new species evolve and coexist. Since the early 1990s research involving over a hundred scientists, financed by many international bodies, has produced numerous reports and publications in widely scattered journals. This article summarizes their main discoveries and examines the status of, and prospects for, the fisheries, as well as current ideas on how their rich endemic fish faunas have evolved. It first considers fisheries projects in each of the three lakes: the deep rift valley lakes Tanganyika and Malawi and the huge Victoria, all of which share their waters between several East African countries. Secondly it considers the biodiversity surveys of each lake, based on underwater (SCUBA) observations of fish ecology and behaviour which have revealed threats to their fish faunas, and considers what conservation measures are needed. Thirdly, using the lakes as laboratories, what have the international investigations (including DNA techniques and follow-up aquarium experiments) now revealed about the origins and relationships of their cichlid species flocks and mechanisms of evolution
The biology and culture of tilapias
The 1980 international conference on the Biology and Culture of Tilapias held in Bellagio, Italy, was a unique gathering of biologists and culturists to review existing information on tilapias and to suggest profitable areas for future work.Tilapia culture, Fishery biology, Conferences Tilapia, Sarotherodon
The changing ecosystem of Lake Victoria, East Africa
Dramatic changes are occurring in the Lake Victoria ecosystem. Two-thirdsof the endemic haplochromine cichlid species, of internationalinterest for studies of evolution, have disappeared, an event associatedwith the sudden population explosion of piscivorous Nile perch (Lates:order Perciformes, family Centropomidae) introduced to the lake somethirty years ago. The total fish yield has, however, increased 5-fold from1970 to 1990, but this yield is now dominated by just three fish species:the introduced Nile perch (lates niloticus, see below*), Nile tilapia(Oreochromis niloticus), and a small endemic pelagic cyprinid(Rastrineobola argentea); these three have replaced a multispeciesfishery. Contemporaneously the lake is becoming increasingly eutrophicwith associated deoxygenation of the bottom waters, thereby reducingfish habitats. Conditions appear to be unstable. There is now an urgentneed for intensive limnological studies to understand the relationshipsbetween these events, and to learn from this unintended large-scale fieldexperiment how to manage the lake to avoid further loss of biodiversityand destruction of fisheries
Recent research in the African Great Lakes: fisheries, biodiversity and cichlid evolution
The East African Great Lakes are now well known for (1) theirfisheries, of vital importance for their rapidly rising riparian humanpopulations, and (2) as biodiversity hotspots with spectacular endemicfaunas, of which the flocks of cichlid fishes unique to each of the threelargest lakes, Tanganyika, Malawi and Victoria, offer uniqueopportunities to investigate how new species evolve and coexist. Sincethe early 1990s research involving over a hundred scientists, financedby many international bodies, has produced numerous reports andpublications in widely scattered journals. This article summarizes theirmain discoveries and examines the status of, and prospects for, thefisheries, as well as current ideas on how their rich endemic fishfaunas have evolved. It first considers fisheries projects in each of thethree lakes: the deep rift valley lakes Tanganyika and Malawi and thehuge Victoria, all of which share their waters between several EastAfrican countries. Secondly it considers the biodiversity surveys ofeach lake, based on underwater (SCUBA) observations of fish ecologyand behaviour which have revealed threats to their fish faunas, andconsiders what conservation measures are needed. Thirdly, using thelakes as laboratories, what have the international investigations(including DNA techniques and follow-up aquarium experiments)now revealed about the origins and relationships of their cichlidspecies flocks and mechanisms of evolution
Rural-Urban Disparities in Emergency Department Intimate Partner Violence Resources
Objective: Little is known about availability of resources for managing intimate partner violence (IPV) at rural hospitals. We assessed differences in availability of resources for IPV screening and management between rural and urban emergency departments (EDs) in Oregon. Methods: We conducted a standardized telephone interview of Oregon ED directors and nurse managers on six IPV-related resources: official screening policies, standardized screening tools, public displays regarding IPV, on-site advocacy, intervention checklists and regular clinician education. We used chi-square analysis to test differences in reported resource availability between urban and rural EDs. Results: Of 57 Oregon EDs, 55 (96%) completed the survey. A smaller proportion of rural EDs, compared to urban EDs, reported official screening policies (74% vs. 100%, p=0.01), standardized screening instruments (21% vs. 55%, p=0.01), clinician education (38% vs. 70%, p=0.02) or on-site violence advocacy (44% vs. 95%, p<0.001). Twenty-seven percent of rural EDs had none or one of the studied resources, 50% had two or three, and 24% had four or more (vs. 0%, 35%, and 65% in urban EDs, p=0.003). Small, remote rural hospitals had fewer resources than larger, less remote rural hospitals or urban hospitals. Conclusion: Rural EDs have fewer resources for addressing IPV. Further work is needed to identify specific barriers to obtaining resources for IPV management that can be used in all hospital settings. [West J Emerg Med. 2011;12(2):178-183.
The Association between Emergency Department Resources and Diagnosis of Intimate Partner Violence
Objective: There is little information about which intimate partner violence (IPV) policies and services assist in the identification of IPV in the emergency department (ED). The objective of this study was to examine the association between a variety of resources and documented IPV diagnoses. Methods: Using billing data assembled from 21 Oregon EDs from 2001 to 2005, we identified patients assigned a discharge diagnosis of IPV. We then surveyed ED directors and nurse managers to gain information about IPV-related policies and services offered by participating hospitals. We combined billing data, survey results and hospital-level variables. Multivariate analysis assessed the likelihood of receiving a diagnosis of IPV depending on the policies and services available. Results: In 754,597 adult female ED visits, IPV was diagnosed 1,929 times. Mandatory IPV screening and victim advocates were the most commonly available IPV resources. The diagnosis of IPV was independently associated with the use of a standardized intervention checklist (OR 1.71, 95% CI 1.04-2.82). Public displays regarding IPV were negatively associated with IPV diagnosis (OR 0.56, 95% CI 0.35-0.88). Conclusions: IPV remains a rare documented diagnosis. Most common hospital-level resources did not demonstrate an association with IPV diagnoses; however, a standardized intervention checklist may play a role in clinicians\u27 likelihood diagnosing IPV
Baseline characteristics predict risk of progression and response to combined medical therapy for benign prostatic hyperplasia (BPH)
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110594/1/bju12802.pd
Effect of Shifting from Combination Therapy to Monotherapy of α-Blockers or 5α-Reductase Inhibitors on Prostate Volume and Symptoms in Patients with Benign Prostatic Hyperplasia
The ichthyofauna of the marginal lagoons of the Sorocaba River, SP, Brazil: composition, abundance and effect of the anthropogenic actions
Benign prostatic hyperplasia as a progressive disease: a guide to the risk factors and options for medical management
Benign prostatic hyperplasia (BPH) is a complex disease that is progressive in many men. BPH is commonly associated with bothersome lower urinary tract symptoms; progressive disease can also result in complications such as acute urinary retention (AUR) and BPH-related surgery. It is therefore important to identify men at increased risk of BPH progression to optimise therapy. Several factors are associated with progression, including age and prostate volume (PV). Serum prostate-specific antigen level is closely correlated with PV, making it useful for determining the risk of BPH progression. Medical therapy is the most frequently used treatment for BPH. 5-alpha-reductase inhibitors impact the underlying disease and decrease PV; this results in improved symptoms, urinary flow and quality of life, and a reduced risk of AUR and BPH-related surgery. Alpha-blockers achieve rapid symptom relief but do not reduce the overall risk of AUR or BPH-related surgery, presumably because they have no effect on PV. Combination therapy provides greater and more durable benefits than either monotherapy and is a recommended option in treatment guidelines. The Combination of Avodart® and Tamsulosin (CombAT) study is currently evaluating the combination of dutasteride with tamsulosin over 4 years in a population of men at increased risk of BPH progression. A preplanned 2-year analysis has shown sustained symptom improvement with combination therapy, significantly greater than with either monotherapy. CombAT is also the first study to show benefit in improving BPH symptoms for combination therapy over the alpha-blocker, tamsulosin, from 9 months of treatment
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