Free Bed Research Articles

Modelling of turbulent flow in a radial reactor with fixed bed

The data of the computation of turbulent flow in the CF-π and CP-π configurations of the radial reactor with a fixed bed are presented. The Reynolds motion equations have been solved jointly with the k-ɛ turbulence model. To couple the parameters of flows at the interface free part-fixed bed the classical continuity equations were used. The computational data are obtained for the averaged and turbulent characteristics, and it is shown that the flow in the fixed bed causes the generation of the turbulence kinetic energy and its dissipation rate; the flow in the CF-π configuration is distributed more uniformly as compared to the CP-π configuration of the radial reactor. Computed data are compared with the experimental ones.

New technique "graft reposition on flap" in allen type iv amputation: a report of six cases.

Allen type IV fingertip amputations were treated by a modified technique, when the replantation is difficult to be performed or not an option. The pre-existing technique involves nail bed grafting and local flap. In the modified technique, a free bone graft is added, bone and free nail bed repositioned and pulp reconstruction by local flap. This can be best described "graft reposition on flap" (GRF). GRF was found to be simple and cost effective. It allows preservation of finger length and a fully functional and cosmetically acceptable nail.

Unsteady Characteristics of Sediment Transport Under Non-harmonic Waves

Sediment transport under waves is one of the key dynamic processes of coastal sediment motion. Previous studies for this issue are mainly based on linear wave theory and quasi-steady simplification. However, waves in real circumstance are always irregular, generally with a certain degree of asymmetry and/or velocity-leaning especially in shallow water. It is envisaged that sediment movement under non-harmonic waves is different from sinusoidal waves. Based on large eddy simulation of turbulent flows in wave boundary layer, a modified method is proposed to calculate sediment transport rate under non-harmonic waves. It is further used to explore the influences of flow acceleration and the phase lead between the free stream velocity and bed shear stress on sediment transport rate in different phases of one wave cycle for forth-leaning. The net transport rate is found to increase with the degree of asymmetry and velocity-leaning index. Both the acceleration and the phase lead have a great influence on average transport rate in each phase.

Fishing with bed nets on Lake Tanganyika: a randomized survey.

BackgroundMalaria is among the most common causes of death along Lake Tanganyika, a problem which many aid organizations have attempted to combat through the distribution of free mosquito bed nets to high-risk communities. The Lake Tanganyika Floating Health Clinic (LTFHC), a health-based non-governmental organization (NGO), has observed residents of the Lake Tanganyika basin using bed nets to fish small fry near the shoreline, despite a series of laws that prohibit bed net use and other fine-gauge nets for fishing, implemented to protect the near-shore fish ecology. The LTFHC sought to quantify the sources of bed nets and whether they were being used for fishing.MethodsThe LTFHC conducted a survey of seven lakeside villages in Lagosa Ward, Tanzania. The government has divided each village into two to six pre-existing geographic sub-villages depending on population size. Seven households per sub-village were chosen at random for survey administration. The survey consisted of 23 questions regarding mosquito bed net practices, including the use of bed nets for fishing, as well as questions pertaining to any perceived changes to the fish supply.ResultsA total of 196 surveys were administered over a four-week period with a 100% response rate. Over 87% of households surveyed have used a mosquito bed net for fishing at some point. The majority of respondents reported receiving their bed net for free (96.4%), observing “many” residents of their village using bed nets for fishing (97.4%), and noticing a subjective decrease in the fish supply over time (64.9%).ConclusionsThe findings of this study raise concerns that the use of free malaria bed nets for fishing is widespread along Lake Tanganyika, and that this dynamic will have an adverse effect on fish ecology. Further studies are indicated to fully define the scope of bed net misuse and the effects of alternative vector control strategies in water-based communities.Electronic supplementary materialThe online version of this article (doi:10.1186/1475-2875-13-395) contains supplementary material, which is available to authorized users.

Free Condom Distribution: What We Don’t Know May Hurt Us

The provision of commodities is an important element of nearly all public health programs. In HIV programs, commodities can be very expensive, like antiretroviral drugs for treatment or prevention, or they can be relatively cheap, like male condoms. Because of the contrast between incomes in developing countries and the costs of life-saving medications like antiretroviral drugs, recipients are often provided expensive medications free of all charge to increase access and encourage adherence. Condoms, on the other hand, are equally essential for prevention of HIV infection, are relatively inexpensive and are often judged to be affordable for users, even in the most resource-constrained settings. Condoms are often sold at a subsidized price through social marketing programs in an effort to make them even more affordable and, in theory, more valued and likely to be used since they require payment. Recently, a debate over the relative merit of free versus subsidized distribution of commodities has developed in other areas of public health. [1] The benefits of free versus subsidized distribution of bed nets for malaria prevention, for example, has been debated and examined in a few small-scale studies. [2–4] Given the cost of bed nets relative to disposable income in many countries, the examination of the role of free bed nets is important in the effort to reduce malaria infection. The provision of relatively inexpensive or even heavily subsidized prevention commodities must be considered in the context of the severely constrained resource environments in which they may be provided. As Jim Yong Kim, President of the World Bank, observed in his speech to the 66th World Health Assembly, “Anyone who has provided health care to poor people knows that even tiny out-of-pocket charges can reduce their use of needed services. This is both unjust and unnecessary.” [5] With the question of whether subsidized pricing or free distribution of essential public health commodities results in greater use and better prevention outcomes being discussed anew, we explored this question for condom distribution as well. We attempted to conduct two parallel systematic reviews, one of condom social marketing and the other of free condom distribution, in low- and middle-income countries. Both reviews followed the PRISMA statement [6] and were an output of the Evidence Project, a joint effort of the Medical University of South Carolina, the World Health Organization and the Johns Hopkins Bloomberg School of Public Health, funded by the U.S. National Institutes of Mental Health. The review of condom social marketing yielded valuable information on that approach. [7] Though the number of studies that could be included was limited and the follow-up periods were short, a meta-analysis showed positive and statistically significant effects of social marketing activities on condom use. The analysis suggested that the cumulative effect of condom social marketing over multiple years could be substantial. The review of free condom distribution was not successful. Though we identified 34 studies that met our inclusion criteria (Figure 1), all provided free condoms as only one component of a more complete intervention package. As a result, we found that it was not possible to isolate the effect of free condom distribution from other co-occurring interventions in the available research literature. We also concluded that it is equally likely many other studies evaluating key interventions distributed condoms for free without noting that fact in the publication. Our main conclusion from this review is that insufficient attention has been paid to evaluating the effect of free condom distribution on condom use and other key HIV prevention outcomes. Figure 1 Free Condom Distribution: Flow chart depicting disposition of study citations Condoms are relatively inexpensive per item. Perhaps as a result, the impact of their cost as a potential barrier to their use has not been examined. The total annual expenditure for condoms worldwide is very large. With levelling or decreasing resources for HIV prevention, maximizing the effectiveness of prevention investments is becoming even more crucial. At the same time, the desire to decrease prevention expenditures by increasing users’ contributions to commodity costs is growing, supported by the belief that users value more what they purchase over what they receive for free. Research from behavioural economics demonstrates the attractiveness of “free” in marketing commodities [8] and evidence from malaria prevention has shown the effect of free commodities on increased use. Studies have been done on price sensitivity of socially marketed condoms and have shown a clear negative correlation between condom prices and sales. [9] However, given the vast number of free condoms distributed each year, it is surprising how little is known about the actual effect on condom use. We recommend well-designed studies to isolate the effect of free versus subsidized or socially marketed condom distribution on condom use.

Exploring the impact of targeted distribution of free bed nets on households bed net ownership, socio-economic disparities and childhood malaria infection rates: analysis of national malaria survey data from three sub-Saharan Africa countries

BackgroundThe last decade has witnessed increased funding for malaria control. Malaria experts have used the opportunity to advocate for rollout of such interventions as free bed nets. A free bed net distribution strategy is seen as the quickest way to improve coverage of effective malaria control tools especially among poorest communities. Evidence to support this claim is however, sparse. This study explored the effectiveness of targeted free bed net distribution strategy in achieving equity in terms of ownership and use of bed nets and also reduction of malaria prevalence among children under-five years of age.MethodsNational malaria indicator survey (MIS) data from Angola, Tanzania and Uganda was used in the analysis. Hierarchical multilevel logistic regression models were used to analyse the relationship between variables of interest. Outcome variables were defined as: childhood test-confirmed malaria infections, household ownership of any mosquito net and children’s use of any mosquito nets. Marginal effects of having free bed net distribution on households with different wealth status were calculated.ResultsAngolan children from wealthier households were 6.4 percentage points less likely to be parasitaemic than those in poorest households, whereas those from Tanzania and Uganda were less likely to test malaria positive by 7 and 11.6 percentage points respectively (p < 0.001). The study estimates and present results on the marginal effects based on the impact of free bed net distribution on children's malaria status given their socio-economic background. Poorest households were less likely to own a net by 21.4% in Tanzania, and 2.8% in Uganda, whereas both poorer and wealthier Angolan households almost achieved parity in bed net ownership (p < 0.001). Wealthier households had a higher margin of using nets than poorest people in both Tanzania and Uganda by 11.4% and 3.9% respectively. However, the poorest household in Angola had a 6.1% net use advantage over children in wealthier households (p < 0.001).ConclusionThis is the first study to use nationally representative data to explore inequalities in bed net ownership and related consequences on childhood malaria infection rates across different countries. While targeted distribution of free bed nets improved overall bed net ownership, it did not overcome ownership inequalities as measured by household socioeconomic status. Use of bed nets was disproportionately lower among poorest children, except for Angola where bed net use was higher among poorest households when compared to children in wealthier households. The study highlights the need for malaria control world governing bodies and policy makers to continue working on finding appropriate strategies to improve access to effective malaria control tools especially by the poorest who often times bears the brunt of malaria burden than their wealthier counterparts.

Household bed net ownership and use among under-5 children in Nigeria.

Malaria remains the leading cause of morbidity and mortality in sub-Saharan Africa, with children under 5 years accounting for 86% of all malaria deaths. For effective control of malaria, WHO recommends rapid diagnosis and effective treatment, insecticide-treated bed nets, and indoor residual spraying. The use of insecticide-treated bed nets has been shown to be the most cost-effective strategy in preventing this infection. However, despite the Roll Back Malaria subsidized and free bed net distribution initiatives in some Africa countries, bed net uptake and usage still remains low in many households. This study aimed to investigate household characteristics and child factors that determine bed net ownership and use amongst under-5 children and the effect of its usage on malaria parasitemia in under-5 children in Nigeria. Data from a nationally representative sample of 5895 households was obtained from the 36 states and the Federal Capital Territory in the 2010 Nigeria demographic and health survey, with a minimum of 67 households enrolled per state. Appropriate statistical tools were used to identify the characteristics of households that owned a bed net and to examine the association between the households and child-level factors that predict the use of bed net and malaria prevalence among under-5 children within these households. The rate of households bed net ownership in Nigeria is about 45.5%. About 48.5% of under-5 children in 33.9% of households surveyed, use a bed net during sleep. There was a strong correlation between households ownership and child sleeping under a bed net (r = 0.706, P < 0.001). Acquisition of these bed nets at no cost significantly determined ownership (P < 0.001) but not usage (P = 0.450). Ownership of a bed net was significantly higher in households in rural areas (P = 0.001), poorer households (P = 0.001), households with an under-5 child (P = 0.001), households whose heads were male (P = 0.001), and of lower educational attainment (P = 0.010). There was a greater likelihood of under-5 children sleeping under a bed net in households with two or more under-5 children (odds ratio [OR] 1.26; CI: 1.05-1.66), two or more bed nets (OR 2.03; CI: 1.56-2.66), and in households whose heads were younger ([OR 2.79; CI: 1.65-4.70] for household heads younger than 29 years and [OR 1.6; CI: 1.17-2.19] for those 30-49 years of age), female (OR 1.61; CI: 1.00-2.61), and poorer (OR 1.77; CI: 1.03-3.04), and less likely in households with more than three other (aside from the under-5 children) household members ([OR 0.23; CI: 0.08-0.69] for household with 4-6 family members and [OR 0.20; CI: 0.07-0.61] for households with 7 or more family members). Malaria parasitemia in under-5 children was higher in: households without a bed net (41.9% versus [vs] 34.2%) (P = 0.016), in children who did not sleep under a bed net (39.7% vs 35.0%) (P = 0.292), in poor households compared to middle and rich households (50.5% vs 44.9% vs 25.9%; P = 0.001), and households in rural settlements (42.6% vs 19.6%) (P = 0.001). Bed net ownership in households in Nigeria is poor and does not translate to usage. Governments and organizations should not just distribute these nets free of charge to households, but also follow up with regular visits and provision of household education to ensure consistent and correct use, especially amongst under-5 children and pregnant women, who are the most vulnerable to infections and complications from malaria.

Abstract P2-10-42: Gene expression profiling to predict the risk of locoregional recurrence in breast cancer

Abstract Background The 70-gene signature (Mammaprint™) has been developed to predict the risk of distant metastases in breast cancer and select those patients who will have benefit in survival from adjuvant treatment. Aside from distant metastases, the development of locoregional recurrence is a significant predictor of survival. Given the strong association between locoregional recurrence and distant recurrence, we hypothesize that the 70-gene signature will be predictive of locoregional recurrence as well. Methods We updated follow-up and radiotherapy details for all 1053 unique breast cancer patients treated at the NKI-AVL who previously participated in various 70-gene signature validation studies. Diagnosis was between 1984 and 2006. All patients were primarily treated surgically with either breast-conservation therapy or mastectomy. Adjuvant treatment consisted of radiotherapy, chemotherapy and/or endocrine therapy as indicated. Known risk factors for locoregional recurrence including age, tumor free resection margins, tumor size, grade, ER status, Her2 status, nodal irradiation and tumor bed boost were included in our analysis in addition to the 70-gene signature result. Results Through 10 years of follow-up, 80 locoregional recurrences occurred. Patients with a 70-gene signature high risk result (n = 492) had a locoregional recurrence risk of 8.8% (95%CI: 6.3–11.3) at 5 years and 13.5 % (95%CI: 10.2–16.8) at 10 years, which was 2.6% (95%CI: 1.2–4.0) at 5 years and 5.7% (95%CI:3.5–7.9) at 10 years for patients with a low risk 70-gene signature (n = 561)(Logrank: p &amp;lt; 0.0001). Accordingly, patients with a high risk 70-gene signature had an approximately 3 times higher risk of locoregional recurrence than patients with a low risk 70-gene signature (univariable hazard ratio (HR) 2.89; 95%CI: 1.80–4.63). Adding the 70-gene signature to a Cox proportional hazard model containing age, size, grade, ER status, involvement of axillary lymph nodes, surgical treatment and adjuvant treatment (radiotherapy, chemotherapy and/or endocrine therapy), significantly improved the model (likelihood ratio: p = 0.007). In that model, the multivariable HR for high versus low 70-gene signature risk was 2.27 (95%CI: 1.24–4.15). Conclusion The 70-gene signature is able to predict the risk of locoregional recurrence, independent of known risk factors. Using the 70-gene signature may help in selecting those patients who will benefit from extensive adjuvant treatment. Additionally, the 70-gene signature may also select a group of patients at a low risk of locoregional recurrence who may be cured with limited local treatment alone. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-10-42.

The Physician as Storyteller &amp; Poet: Quick Writes from East Bay Writers’ Workshops

One weekend day during my medical internship at Lincoln Hospital in the South Bronx, probably a Saturday, I received an admission. She was a woman in her mid thirties, well known to the medical service, with chronic renal failure. Every few weeks she would come into the emergency room with fluid retention and elevated potassium, and we would hustle around to get her to the ICU where we could initiate peritoneal dialysis. Our ICU had 7 beds for our indigent population of 350,000 and it was shared by all of the services: Medicine, Peds, Surgery, OB. There was never a free bed, so finding a bed for one patient always required a lot of negotiation and weight-throwing. To make it worse, she came at around shift change when it is always difficult to get anyone moved in or out of a bed. I have never been very good at weight-throwing and having started my career as an orderly and scrub nurse, I am very uncomfortable about “yelling” at the staff, which was what was required. Before I could get my patient into the ICU, place the catheter, and start the dialysis, she had a cardiac arrest and died. I took the full load of her death onto my shoulders. How had I let this woman die leaving her children (two, or three as I now remember) motherless? I had failed when my colleagues had succeeded and why couldn't I have been more forceful and aggressive? I went home the next day in a dark mood. I felt as if I was a harmful, dangerous person who had no business becoming a doctor. I thought about throwing myself under a bus or at least breaking my leg on a lamppost. It was all I could do to come in to rounds on Monday. I had to tell my team my story and how I had let them down. Our attending physician, who was also our nephrologist, listened patiently to my tale of failure then calmly told me that I had not killed the patient. The attending reassured me that the patient was killed by her kidney disease and a social system whose best solution was prolonged dialysis. She also reassured me that she would be happy to yell at the staff, if I ever needed help with that in the future.

On a momentum conservative z-layer unstructured C-grid ocean model with flooding

We present a z-layer unstructured C-grid finite volume hydrostatic model. An efficient and highly scalable implicit technique for solution of the free surface equation is combined with an Eulerian approach for the advection of momentum. We show that an accurate velocity reconstruction procedure is of crucial importance not only for discretization of the Coriolis term, but also for the correct advection of momentum, especially in the multilayer case. Unlike other z-layer models the method presented here ensures that the staircase representation of bathymetry and free surface has no influence on the vertical structure of the flow. The method is therefore guaranteed to be strictly momentum conservative, also in the layers containing the free surface and bed. A number of test cases are presented to show that the model is able to accurately simulate Coriolis dominated flows and flooding and drying processes both in the depth-averaged case and in the presence of multiple z-layers. We use a simulation of 2004 Indian Ocean tsunami to evaluate the ability of the method to simulate fast propagating tsunami waves and detailed inundation processes. Results obtained using two different rupture models are compared to the tide gauge arrival times, satellite altimetry data and the inundation observations in the Banda Aceh area. The comparison is used not only to assess the quality of the underlying rupture models but also to determine the value of the available data sources for such an assessment.

Meso-scale coupling model of DEM and CIP for nucleation processes in wet granulation

This paper presents a coupling of Discrete Element Method (DEM) and Constrained Interpolation Profile (CIP) mainly designed for simulations of the nucleation process in wet granulation. The governing equations for fluid (liquid and gas) phases are the volume averaged form of the Navier–Stokes equation, continuity and colour function equations. These equations are solved by use of a meso-scale fixed Cartesian grid whose cell is larger than individual particles. The solid–liquid–gas interfacial effects on both fluid and particle phases are taken into account in the simulation. The surface tension effect on the fluid motion was modelled in three different ways depending on the relative position of the liquid–gas interfaces to powder beds: the models outside, inside, and on the surface of powder beds correspond to a free surface, capillary action and bed surface wetting. A new model for the surface tension effect on the solid (particle) motion, i.e. the capillary force effect, is proposed in this paper. This capillary force model is particularly useful when using a meso-scale fixed grid, and it can be used with various types of multi-fluid scheme such as CIP, Volume of Fluid (VoF) and Level Set methods. The proposed models are validated by comparing the simulation results with theoretical and experimental results. It is also revealed that the capillary force model is crucial to obtain reasonable simulation results for nucleation process.

The use and misuse of mass distributed free insecticide-treated bed nets in a semi-urban community in Rivers State, Nigeria

Insecticide-treated bed net (ITN) is currently distributed free of charge to vulnerable groups in Nigeria, for malaria control. Consistent use of the nets is required for maximum effectiveness; but studies indicate that the nets are often jettisoned in periods of low mosquito activity and high night time temperature. The objective of this study has been to assess the use of mass distributed nets in a semi-urban community in Rivers State, south-south Nigeria, during the late dry season, when mosquito activity is at the lowest in the community. The study was carried out in Ishiodu - Emohua, using a cross-sectional study design. The data was collected using a structured, interviewer-administered questionnaire, administered to female head of households in the community, with under-five children. A total of 170 respondents were studied; they had an average age of 34.3 ± 7.6 years, most were married (86.5%), and had secondary school education (68.2%). All the households owned at least one ITN, and an average of 1.7 nets, with 75.3% of the households owning two or more ITNs. Almost all the nets (99.4%) were obtained free of charge. Of the 170 households that received the nets, 71.8% had hanged the nets as at the time of the survey; 83.6% of these hanged the nets over a bed, while 10.7% used the nets as window curtain. Of the 102 ITNs that were properly deployed, only 27.5% were occupied the night before the survey, by an average of 2.5 persons, mainly under-five children (37.7%). The distribution of free ITNs has resulted in universal household ownership, but the use of the nets is still very poor. Proper health education is required to encourage the consistent use of the nets, even in hot night, with low mosquito activity.

Kostennutzenanalyse der Therapie von Risikopatienten am Beispiel tiefer Sternuminfektionen

Each and every hospital of any kind is forced, due to increased cost pressure, to work as economically and as efficiently as possible. This even applies when the operational orientations of the hospitals institutions are different. In the present article an analysis of the repercussions of the treatment of postoperative complications in terms of entrepreneurial practice is given. Our focus is on the opportunity cost. A theoretical calculation of opportunity costs is made based on the example of postoperative infections following cardiac surgery and the resulting treatment. The bases of the examinations are the results collected at the hospital Mediclin Herzentrum Lahr / Baden in 2008. The wound healing disorders were recorded from November 2004 until November 2007 and include 3675 patients who were operated on using a median sternotomy. Out of the 3675 patients 45 (1.2 %) were affected. Various treatment options are at hand. The used therapy algorithm in our practice is dependent on the stage and the development of the infection. If the high trim point, the medial trim point and the low trim point of the mediastinitis patients, as well as the average revenue and the surcharge omission on exceeding the high trim point (these data can be found in the annual accounts) and knowledge of the actual length of stay of the mediastinitis patient are known, the opportunity cost, respectively potential turnover increases, can be calculated. Reducing the medial trim point from 48.43 to, for example, 36.37 days could potentially produce a turnover increase of as much as 10 633.41 €. Keeping patient safety in mind, significant turnover increases can be achieved with adequate planning. The considered sales situation, however, can only be achieved under the same terms: these being free operating room and bed capacities, available personnel, equal cost of materials as well as enough patients. The consideration of opportunity costs could be important for entrepreneurs if staff shortage continues and, in economical terms, non-expendable capacities are created.

Seasonal Performance of an Outdoor Constructed Wetland for Graywater Treatment in a Temperate Climate

The seasonal treatment efficiency of a pilot-scale constructed wetland system located outdoors in a semi-arid, temperate climate was evaluated for graywater in a comprehensive, 1-year study. The system consisted of two wetland beds in series--a free water surface bed followed by a subsurface flow bed. Water quality monitoring evaluated organics, solids, nutrients, microbials, and surfactants. The results showed that the wetland substantially reduced graywater constituents during fall, spring, and summer, including biochemical oxygen demand (BOD) (92%), total nitrogen (85%), total phosphorus (78%), total suspended solids (TSS) (73%), linear alkylbenzene sulfonate (LAS) surfactants (94%), and E. coli (1.7 orders of magnitude). Except for TSS, lower removals of graywater constituents were noted in winter--BOD (78%), total nitrogen (64%), total phosphorus (65%), LAS (87%), and E. coli (1.0 order), indicating that, although wetland treatment slowed during the winter, the system remained active, even when the average water temperature was 5.2 +/- 4.5 degrees C.

Stability analysis of flat- and corrugated-wall bubbling fluidized beds: Differential pressure, heat transfer coefficient, digital image analysis and CFD simulations

Corrugated walls were used in gas–solid bubbling fluidized beds to reduce minimum bubbling velocity and improve gas distribution. A thorough stability analysis of flat-wall (FWBFB) and corrugated-wall (CWBFB) bubbling fluidized beds was carried out using several geometrical bed declinations and operating conditions covering corrugation angles, clearances, initial rest bed heights and ratios of gas velocity to minimum bubbling velocity, U g/ U mb. Standard deviations of dynamic fluctuations for measured indicators such as bed differential pressure, wall-to-bed heat transfer coefficient, bed free surface and bed mean gray scale intensity (via digital image analysis), and simulated indicators (via 3-D CFD simulations) such as granular temperature and pressure, and solids volume fraction were monitored to compare the stability behaviors of FWBFB and CWBFB. It was concluded that at a given U g/ U mb, CWBFB offered more stable gas–solid fluidization operation than FWBFB. Every system turned more unstable with the increase in U g/ U mb, rest bed height and corrugation angle, but proved relatively insensitive to wall clearance. Full 3-D transient Euler–Euler CFD simulations were corroborated with experimental findings and further revealed that necks (narrowest clearances) were mainly responsible for the growth of instabilities in CWBFB as compared to hips (largest clearances).

Best practices for an insecticide-treated bed net distribution programme in sub-Saharan eastern Africa

Insecticide-treated bed nets are the preeminent malaria control means; though there is no consensus as to a best practice for large-scale insecticide-treated bed net distribution. In order to determine the paramount distribution method, this review assessed literature on recent insecticide treated bed net distribution programmes throughout sub-Saharan Eastern Africa. Inclusion criteria were that the study had taken place in sub-Saharan Eastern Africa, targeted malaria prevention and control, and occurred between 1996 and 2007. Forty-two studies were identified and reviewed. The results indicate that distribution frameworks varied greatly; and consequently so did outcomes of insecticide-treated bed net use. Studies revealed consistent inequities between urban and rural populations; which were most effectively alleviated through a free insecticide-treated bed net delivery and distribution framework. However, cost sharing through subsidies was shown to increase programme sustainability, which may lead to more long-term coverage. Thus, distribution should employ a catch up/keep up programme strategy. The catch-up programme rapidly scales up coverage, while the keep-up programme maintains coverage levels. Future directions for malaria should include progress toward distribution of long-lasting insecticide-treated nets.

1D numerical evaluation of dike erosion due to overtopping

Dike overtopping is an important issue in both scientific and practical aspects of sediment embankment erosion. This research is concerned with the validation of a one-dimensional numerical code applied to an unsteady two-phase flow over an initially trapezoidal-shaped sediment dike, including the transition from sub- to supercritical flows and the flow propagation over a steep slope. The approach is based on the shallow-water equations coupled with a sediment erosion code. The numerical results are compared with recent laboratory experiments, resulting in a reasonable prediction of the temporal free surface and bed evolution. The remaining model inaccuracies mainly originate from overflow initiation with extremely small flow depths, streamline curvature effects with the related underestimation of flow velocities close to the sediment surface, and the changing saturation in the dike body not accounted for in the model. Despite these deficiencies, the computational model will be helpful, particularly in flood risk assessment and management.

Palliative care for patients with hematological malignancies—a case series

Palliative care for patients with hematological malignancies—a case series

Bed net ownership in Kenya: the impact of 3.4 million free bed nets

BackgroundIn July and September 2006, 3.4 million long-lasting insecticide-treated bed nets (LLINs) were distributed free in a campaign targeting children 0-59 months old (CU5s) in the 46 districts with malaria in Kenya. A survey was conducted one month after the distribution to evaluate who received campaign LLINs, who owned insecticide-treated bed nets and other bed nets received through other channels, and how these nets were being used. The feasibility of a distribution strategy aimed at a high-risk target group to meet bed net ownership and usage targets is evaluated.MethodsA stratified, two-stage cluster survey sampled districts and enumeration areas with probability proportional to size. Handheld computers (PDAs) with attached global positioning systems (GPS) were used to develop the sampling frame, guide interviewers back to chosen households, and collect survey data.ResultsIn targeted areas, 67.5% (95% CI: 64.6, 70.3%) of all households with CU5s received campaign LLINs. Including previously owned nets, 74.4% (95% CI: 71.8, 77.0%) of all households with CU5s had an ITN. Over half of CU5s (51.7%, 95% CI: 48.8, 54.7%) slept under an ITN during the previous evening. Nearly forty percent (39.1%) of all households received a campaign net, elevating overall household ownership of ITNs to 50.7% (95% CI: 48.4, 52.9%).ConclusionsThe campaign was successful in reaching the target population, families with CU5s, the risk group most vulnerable to malaria. Targeted distribution strategies will help Kenya approach indicator targets, but will need to be combined with other strategies to achieve desired population coverage levels.

Modeling turbulent flow from dam break using slow manifolds

We present a novel approach based on centre manifold techniques to describe the large scale dynamics of the mean turbulent dam-break flow. We avoid empirical assumptions about the cross-stream profile of the velocity; instead a solution is obtained using free surface and bed boundary conditions that accommodate constant turbulent shear as an approximately neutral mode. We describe the turbulent dynamics across the flow, and identify important factors affecting the turbulent dissipation in the lateral direction. Available experimental data verify the results. References J. Carr. Applications of centre manifold theory, volume 35 of Applied Mathematical Sciences. Springer--Verlag, 1981. D. J. Georgiev, A. J. Roberts, and D. V. Strunin. The dynamics of the vertical structure of turbulence in flood flows. ANZIAM Journal, 48(CTAC-2006):C573--C590, 2007. http://anziamj.austms.org.au/ojs/index.php/ANZIAMJ/article/view/124. D. J. Georgiev, A. J. Roberts, and D. V. Strunin. Nonlinear dynamics on centre manifolds describing turbulent floods: $k$-$\omega $ model. Discrete and Continuous Dynamical Systems Supplements, (Special):419--428, 2007. http://aimsciences.org/journals/pdfs.jsp?paperID=2848&mode=full. A. J. Hogg and D. Pritchard. The effects of hydraulic resistance on dam-break and other shallow inertial flows. Journal of Fluid Mechanics, 501:179--212, 2004. I. M. Janosi, D. Jan, K. G. Szabo, and T. Tel. Turbulent drag reduction in dam-break flows. Experiments in Fluids, 37:219--229, 2004. P. Keast and P. H. Muir. {EPDCOL}: A more efficient {PDECOL} code. ACM Transactions on Mathematical Software, 17(2):153--166, 1991. Y. A. Kuznetsov. Elements of applied bifurcation theory, volume 112 of Applied Mathematical Sciences. Springer--Verlag, 1995. N. K. Madsen and R. F. Sincovec. {PDECOL}: General collocation software for partial differential equations. ACM Transactions on Mathematical Software, 5(3):326--351, 1979. I. Nezu. Open-channel flow turbulence and its research prospects in the 21st century. Journal of Hydraulic Engineering, 131(4):229--246, April 2005. T. M. Oezgoekmen, T. Iliescu, P. F. Fischer, A. Srinivasan, and J. Duan. Large eddy simulation of stratified mixing and two-dimensional dam-break problem in a rectagular enclosed domain. Ocean Modelling, 16:106--140, 2007. A. J. Roberts. Low-dimensional modelling of dynamics via computer algebra. Computer Physics Communications, 100:215--230, 1997. A. J. Roberts. Computer algebra describes flow of turbulent floods via the Smagorinsky large eddy closure. Technical report, University of Southern Queensland, 2008. http://eprints.usq.edu.au/4008/. A. J. Roberts, D. J. Georgiev, and D. V. Strunin. Model turbulent floods with the Smagorinski large eddy closure. http://arxiv.org/abs/0805.3192/. P. K. Stansby, A. Chegini, and T. C. D. Barnes. The initial stages of dam-break flow. Journal of Fluid Mechanics, 374:407--424, 1998.