Construction of some new three associate class partially balanced incomplete block designs in two replicates

Paper presented at the 2nd Strathmore International Mathematics Conference (SIMC 2013), 12 - 16 August 2013, Strathmore University, Nairobi, Kenya.Search for experimental designs which aid in research studies involving large number of treatments with minimal experimental units has been desired overtime. This paper constructs some new series of three associate Partially Balanced Incomplete Block (PBIB) designs having n(n - 2) /4 treatments with three associate classes in two replicates using the concept of triangular association scheme. The design is constructed from an even squared array of n rows and n columns (n _> 8) with its both diagonal entries bearing no treatment entries and that given the location of any treatment in the squared array, the other location of the same treatment in the array is predetermined. The design and association parameters for a general case of an even integer n >_8 are obtained with an illustrated case for n = 8. Efficiencies of the designs within the class of designs are obtained for a general case of even n >_8 with a listing of efficiencies of designs with blocks sizes in the interval [8,22]. The designs constructed have three associate classes and are irreducible to minimum number of associate classes.Search for experimental designs which aid in research studies involving large number of treatments with minimal experimental units has been desired overtime. This paper constructs some new series of three associate Partially Balanced Incomplete Block (PBIB) designs having n(n - 2) /4 treatments with three associate classes in two replicates using the concept of triangular association scheme. The design is constructed from an even squared array of n rows and n columns (n _> 8) with its both diagonal entries bearing no treatment entries and that given the location of any treatment in the squared array, the other location of the same treatment in the array is predetermined. The design and association parameters for a general case of an even integer n >_8 are obtained with an illustrated case for n = 8. Efficiencies of the designs within the class of designs are obtained for a general case of even n >_8 with a listing of efficiencies of designs with blocks sizes in the interval [8,22]. The designs constructed have three associate classes and are irreducible to minimum number of associate classes

Estudo in vitro e in vivo da eficácia anti leishmaniótica de terapêutica combinada de Diminazene e Artesunate contra Leishmania donovani em camundongos Balb/c

The in vitro and in vivo activity of diminazene (Dim), artesunate (Art) and combination of Dim and Art (Dim-Art) against Leishmania donovani was compared to reference drug; amphotericin B. IC50 of Dim-Art was found to be 2.28 ± 0.24 µg/mL while those of Dim and Art were 9.16 ± 0.3 µg/mL and 4.64 ± 0.48 µg/mL respectively. The IC50 for Amphot B was 0.16 ± 0.32 µg/mL against stationary-phase promastigotes. In vivo evaluation in the L. donovani BALB/c mice model indicated that treatments with the combined drug therapy at doses of 12.5 mg/kg for 28 consecutive days significantly (p < 0.001) reduced parasite burden in the spleen as compared to the single drug treatments given at the same dosages. Although parasite burden was slightly lower (p < 0.05) in the Amphot B group than in the Dim-Art treatment group, the present study demonstrates the positive advantage and the potential use of the combined therapy of Dim-Art over the constituent drugs, Dim or Art when used alone. Further evaluation is recommended to determine the most efficacious combination ratio of the two compounds.A atividade in vitro e in vivo de Diminazene (Dim), Artezunate (Art) e a combinação Dim e Art (Dim-Art) contra Leishmania donovani foi comparada com a droga de referência Anfotericina B. IC50 da Dim-Art foi 2,28 ± 0,24 µg/mL enquanto aquelas de Dim e Art foram 9,16 ± 0,3 µg/mL e 4,64 ± 0,48 µg/mL respectivamente. O IC50 da Anfotericina B foi 0,16 ± 0,32 µg/mL contra a fase estacionária de promastigotas. A avaliação in vivo do modelo de L. donovani em camundongos Balb/c indicou que os tratamentos com a terapêutica de drogas combinadas em doses de 12,5 mg/kg por 28 dias consecutivos significantemente (p < 0,001) reduziu a carga parasitária no baço quando comparada a tratamentos com uma única droga dada nas mesmas dosagens. Embora a carga parasitária tenha sido levemente mais baixa (p < 0.05) no grupo Anfotericina B quando comparada com o grupo tratado Dim-Art, o estudo presente demonstra a vantagem positiva do uso potencial da terapêutica combinada Dim-Art sobre drogas como Dim ou Art quando usadas isoladamente. Posterior avaliação é recomendada para determinar a média de combinação mais eficaz dos dois compostos

Engineering standards for trauma and orthopaedic implants worldwide : a systematic review protocol

Introduction Despite multiple scandals in the medical implant sector, premarket testing has been the attention of little published research. Complications related to new devices, such as the DePuy Articular Surface Replacement (ASR, DePuy Synthes, USA), have raised the issue of how designs are tested and whether engineering standards remain up to date with our understanding of implant biomechanics. Despite much work setting up national joint registries to improve implant monitoring, there have been few academic studies examining the premarket engineering standards new implants must meet. Emerging global economies mean that the markets have changed, and it is unknown to what degree engineering standards vary around the world. Governments, industry and independent regulatory bodies all produce engineering standards; therefore, the comparison of surgical implants across different manufacturers and jurisdictions is difficult. In this review, we will systematically collate and compare engineering standards for trauma and orthopaedic implants around the world. This will help inform patient, hospital and surgeon choice and provide an evidence base for future research in this area. Methods and analysis This protocol is based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocol (PRISMA-P) guidelines. We will conduct a systematic review of trauma and orthopaedic engineering standards from four main sources of information as identified in our preliminary scoping searches: governments, industry, independent regulatory bodies and engineering and medical publications. Any current standard relevant to trauma and orthopaedic implants will be included. We will use a predefined search strategy and follow the recommendations of the Cochrane handbook where applicable. We will undertake a narrative synthesis with qualitative evaluation of homogeneity between engineering standards. Ethics and dissemination No ethics approval is required as no primary data are being collected. The results will be made available by peer-reviewed publication and reported according to PRISMA-P guidelines

Aspects determining the risk of pesticides to wild bees: risk profiles for focal crops on three continents.

In order to conduct a proper risk assessment of pesticides to bees, information is needed in three areas: (i) the toxicity of the pesticide; (ii) the probability of bee exposure to that pesticide; and (iii) the population dynamics of the bee species in question. Information was collected on such factors affecting pesticide risk to (primarily wild) bees in several crops in Brazil, Kenya and The Netherlands. These data were used to construct ?risk profiles? of pesticide use for bees in the studied cropping systems. Data gaps were identified and potential risks of pesticides to bees were compared between the crops. Initially, risk profiling aims to better identify gaps in our present knowledge. In the longer term, the established risk profiles may provide structured inputs into risk assessment models for wild and managed bees, and lead to recommendations for specific risk mitigation measures.Edição dos Proceedings of the 11 International Symposium Hazards of Pesticides to Bees, Wageningen, nov. 2011

Using the WHO-AIMS to inform development of mental health systems: the case study of Makueni County, Kenya

Background In order to develop a context appropriate in mental health system, there is a need to document relevant existing resources and practices with a view of identifying existing gaps, challenges and opportunities at baseline for purposes of future monitoring and evaluation of emerging systems. The World Health Organization Assessments Instrument for Mental Health Systems (WHO-AIMS) was developed as a suitable tool for this purpose. Our overall objective of this study, around which research questions and specific aims were formulated, was to establish a baseline on mental health system as at the time of the study, at Makueni County in Kenya, using the WHO-AIMS. Methods To achieve our overall objective, answer our research questions and achieve specific aims, we conducted a mixed methods approach in which we did an audit of DHIS records and county official records, and conducted qualitative interviews with the various officers to establish the fidelity of the data according to their views. The records data was processed via the prescribed WHO-Aims 2.2 excel spreadsheet while the qualitative data was analyzed thematically. This was guided by the six domains stipulated in the WHO AIMS. Results We found that at the time point of the study, there were no operational governance, policy or administrative structures specific to mental health, despite recognition by the County Government of the importance of mental health. The identified interviewees and policy makers were cooperative and participatory in identifying the gaps, barriers and potential solutions to those barriers. The main barriers and gaps were human and financial resources and low prioritization of mental health in comparison to physical conditions. The solutions lay in bridging of the gaps and addressing the barriers. Conclusion There is a need to address the identified gaps and barriers and follow up on solutions suggested at the time of the study, if a functional mental health system is to be achieved at Makueni County

Perceived impacts as narrated by service users and providers on practice, policy and mental health system following the implementation of the mhGAP-IG using the TEAM model in a rural setting in Makueni County, Kenya: a qualitative approach

Background A team approach is key to reduction of the mental health treatment gap. It requires collaborative effort of all formal and informal community based service providers and the consumers of the services. Qualitative evaluations of such an approach add value to the quantitative evaluations. Methods A qualitative study was conducted among 205 participants. These were grouped into a total of 19 focus group discussions for community health workers (CHW), traditional healers (TH), faith healers (FH) and patients. For nurses and clinical officers we held 10 key informant interviews and three key informant discussions. We aimed to document personal perceptions as expressed in narratives on mental health following a community based application of the WHO mental health treatment Gap-intervention guideline (mhGAP-IG) using the TEAM model. We also aimed to document how the narratives corroborated key findings on the quantitative wing of the TEAM model. Results There were three categories of perceptions: (i) patient-related, (ii) health provider-related and, (iii) health system related. The patient related narratives were linked to improvement in their mental and physical health, increased mental health awareness, change in lifestyle and behavior, enhanced social functioning and an increase in family productivity. Health provider perceptions were related to job satisfaction, capacity building and increased interest in mental health training. Mental health system related narratives included effectiveness and efficiency in service delivery and increase in number of referrals at the primary health care facilities. Conclusion The TEAM is a feasible model for the implementation of the mhGAP-IG. It led to positive perceptions and narratives by service provides and service consumers. The qualitative findings corroborated the quantitative findings of TEAM

In vitro and in vivo antileishmanial efficacy of a combination therapy of diminazene and artesunate against Leishmania donovani in BALB /c mice

The in vitro and in vivo activity of diminazene (Dim), artesunate (Art) and combination of Dim and Art (Dim-Art) against Leishmania donovani was compared to reference drug; amphotericin B. IC50 of Dim-Art was found to be $2.28 \pm 0.24 \mu$ g/mL while those of Dim and Art were $9.16 \pm 0.3 \mu$ g/mL and $4.64 \pm 0.48 \mu$ g/mL respectively. The IC50 for Amphot B was $0.16 \pm 0.32 \mu$ g/mL against stationary-phase promastigotes. In vivo evaluation in the L. donovani BALB/c mice model indicated that treatments with the combined drug therapy at doses of 12.5 mg/kg for 28 consecutive days significantly ($p < 0.001$) reduced parasite burden in the spleen as compared to the single drug treatments given at the same dosages. Although parasite burden was slightly lower ($p < 0.05$) in the Amphot B group than in the Dim-Art treatment group, the present study demonstrates the positive advantage and the potential use of the combined therapy of Dim-Art over the constituent drugs, Dim or Art when used alone. Further evaluation is recommended to determine the most efficacious combination ratio of the two compounds.Comment: 4 Pages, 3 Figure

Studies on the mechanical stretchability of transparent conductive film based on graphene-metal nanowire structures

Transparent electrodes with superior flexibility and stretchability as well as good electrical and optical properties are required for applications in wearable electronics with comfort designs and high performances. Here, we present hybrid nanostructures as stretchable and transparent electrodes based on graphene and networks of metal nanowires, and investigate their optical, electrical, and mechanical properties. High electrical and optical characteristics, superb bendability (folded in half), excellent stretchability (10,000 times in stretching cycles with 100% in tensile strain toward a uniaxial direction and 30% in tensile strain toward a multi-axial direction), strong robustness against electrical breakdown and thermal oxidation were obtained through comprehensive study. We believe that these results suggest a substantial promise application in future electronicsopen1