882 resultados para Ineffective Nodulation


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Kenya has experienced a rapid expansion of the education system partly due to high government expenditure on education. Despite the high level of expenditure on education, primary school enrolment has been declining since early 1990s and until 2003 when gross primary school enrolment increased to 104 percent after the introduction of free primary education. However, with an estimated net primary school enrolment rate of 77 percent, the country is far from achieving universal primary education. The worrying scenario is that the allocations of resources within the education sector seems to be ineffective as the increasing expenditure on education goes to recurrent expenditure (to pay teachers salaries). Kenya's Poverty Reduction Strategy Paper (PRSP) and the Economic Recovery Strategy for wealth and Employment Creation (ERS) outlines education targets of reaching universal primary education by 2015. The Government is faced with budget constrains and therefore the available resources need to be allocated efficiently in order to realize the education targets. The paper uses Budget Negotiation Framework (BNF) to analyze the cost effective ways of resource allocation in the primary education sector to achieve universal primary education and other education targets. Budget Negotiation Framework is a tool that aims at achieving equity and efficiency in resource allocation. Results from the analysis shows that universal primary education by the year 2015 is a feasible target for Kenya. The results also show that with a more cost- effective spending of education resources - increased trained teachers, enhanced textbook supplies and subsidies targeting the poor - the country could realize higher enrolment rates than what has been achieved with free primary education.

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Standard models of law enforcement involve the apprehension and punishment of a single suspect, but in many contexts, punishment is actually imposed on an entire group known to contain the offender. The advantages of .group punishment. are that the offender is punished with certainty and detection costs are saved. The disadvantage is that innocent individuals are punished. We compare individual and group punishment when social welfare depends on fairness, and when it depends on deterrence. We show that group punishment may dominate in the former case if the detection technology is ineffective but never in the latter case. We discuss our results in the context of several examples.

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Tuberculosis is the leading cause of death in the world due to a single infectious agent, making it critical to investigate all aspects of the immune response mounted against the causative agent, Mycobacterium tuberculosis , in order to better treat and prevent disease. Previous observations show a disparity in the ability to control mycobacterial growth between mouse strains sufficient in C5, such as C57BL/6 and B10.D2/nSnJ, and those naturally deficient in C5, such as A/J and B10.D2/nSnJ, with C5 deficient mice being more susceptible. It has been shown that during M. tuberculosis infection, C5 deficient macrophages have a defect in production of interleukin (IL)-12, a cytokine involved in the cyclical activation between infected macrophages and effector T cells. T cells stimulated by IL-12 produce interferon (IFN)-γ, the signature cytokine of T helper type 1 (Th1) cells. It is known that a cell-mediated Th1 response is crucial for control of M. tuberculosis in the lungs of humans and mice. This study demonstrates that murine T cells express detectable levels of CD88, a receptor for C5a (C5aR), following antigen presentation by macrophages infected with mycobacteria. T cells from C5 deficient mice infected with M. tuberculosis were found to secrete less IFN-γ and had a reduced Th1 phenotype associated with fewer cells expressing the transcription factor, T-box expressed in T cells (T-bet). The altered Th1 phenotype in M. tuberculosis infected C5 deficient mice coincided with a rise in IL-4 and IL-10 secretion from Th2 cells and inducible regulatory T cells, respectively. It was found that the ineffective T cell response to mycobacteria in C5 deficient mice was due indirectly to a lack of C5a via poor priming by infected macrophages and possibly by a direct interaction between T cells and C5a peptide. Therefore, these studies show a link between the cells of the innate and adaptive arms of the immune system, macrophages and T cells respectively, that was mediated by C5a using a mouse model of M. tuberculosis infection. ^

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Naltrexone, an opioid antagonist, was the second drug approved for treatment of alcohol dependence in the U.S. Its approval followed two landmark studies published in the U.S. in 1992. [1, 2] These studies showed that a combined treatment of naltrexone and behavioral therapy reduced alcohol consumption in alcoholics. Opioid antagonists decrease craving for alcohol and help to reduce drinking by blocking opioid peptide receptors in the body that are active in a dopamine chemical reward system. ^ Despite their usefulness, opioid antagonists have been underutilized. Health providers not educated in the use of opioid antagonists hold the view that opioid antagonist therapy is ineffective. However, it is apparent from the relevant literature that this therapy, when properly understood and targeted, has the potential to make a positive contribution in treating alcohol dependent patients. ^ This thesis will review the scientific literature and the present body of knowledge regarding opioid antagonists (naltrexone) and their pharmacological role in treating alcohol dependence.^

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Physical activity is an important health-promoting behavior to prevent and control chronic disease. Interventions to increase physical activity are vitally needed. Women are not meeting the recommended goals for physical activity - a behavior that has been shown to effectively reduce the incidence of chronic disease and the medical costs associated with treating it. Among many factors predicting physical activity and the different forms of interventions that have been applied, physician counseling is one potentially cost-effective approach that may produce at least modest effects on women's behavior. The Centers for Disease Control and Prevention has published standards for physician counseling of patients regarding physical activity. This study used a short questionnaire to assess the degree to which a group practice of cardiology physicians in Texas queried and discussed physical activity recommendations to older women that they treat and whether they are meeting the physical activity counseling goals of the Centers for Disease Control and Prevention. The majority of this group of physicians counseled patients without benefit of exploring patient behavior. Although these physicians "agreed" that physical activity delayed or prevented disease, the outcome suggests that low self-efficacy hampered efforts to counsel older women on this. Physicians' perceptions that counseling may be ineffective could explain the lower rate of physical activity counseling that does not meet the goals of the Centers for Disease Control and Prevention. ^

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Hemophilia A is a clotting disorder caused by functional factor VIII (FVIII) deficiency. About 25% of patients treated with therapeutic recombinant FVIII develop antibodies (inhibitors) that render subsequent FVIII treatments ineffective. The immune mechanisms of inhibitor formation are not entirely understood, but circumstantial evidence indicates a role for increased inflammatory response, possibly via stimulation of Toll-like receptors (TLRs), at the time of FVIII immunization. I hypothesized that stimulation through TLR4 in conjunction with FVIII treatments would increase the formation of FVIII inhibitors. To test this hypothesis, FVIII K.O. mice were injected with recombinant human FVIII with or without concomitant doses of TLR4 agonist (lipopoysaccharide; LPS). The addition of LPS combined with FVIII significantly increased the rate and the production of anti-FVIII IgG antibodies and neutralizing FVIII inhibitors. In the spleen, repeated in vivo TLR4 stimulation with LPS increased the relative percentage of macrophages and dendritic cells (DCs) over the course of 4 injections. However, repeated in vivo FVIII stimulation significantly increased the density of TLR4 expressed on the surface of all spleen antigen presenting cells (APCs). Culture of splenocytes isolated from mice revealed that the combined stimulation of LPS and FVIII also synergistically increased early secretion of the inflammatory cytokines IL-6, TNF-α, and IL-10, which was not maintained throughout the course of the repeated injections. While cytokine secretion was relatively unchanged in response to FVIII re-stimulation in culture, LPS re-stimulation in culture induced increased and prolonged inflammatory cytokine secretion. Re-stimulation with both LPS and FVIII induced cytokine secretion similar to LPS stimulation alone. Interestingly, long term treatment of mice with LPS alone resulted in splenocytes that showed reduced response to FVIII in culture. Together these results indicated that creating a pro-inflammatory environment through the combined stimulation of chronic, low-dose LPS and FVIII changed not only the populations but also the repertoire of APCs in the spleen, triggering the increased production of FVIII inhibitors. These results suggested an anti-inflammatory regimen should be instituted for all hemophilia A patients to reduce or delay the formation of FVIII inhibitors during replacement therapy.

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Documented risks of physical activity include reduced bone mineral density at high activity volume, and sudden cardiac death among adults and adolescents. Further illumination of these risks is needed to inform future public health guidelines. The present research seeks to 1) quantify the association between physical activity and bone mineral density (BMD) across a broad range of activity volume, 2) assess the utility of an existing pre-screening questionnaire among US adults, and 3) determine if pre-screening risk stratification by questionnaire predicts referral to physician among Texas adolescents. ^ Among 9,468 adults 20 years of age or older in the National Health and Nutrition Examination Survey (NHANES) 2007-2010, linear regression analyses revealed generally higher BMD at the lumbar spine and proximal femur with greater reported activity volume. Only lumbar BMD in women was unassociated with activity volume. Among men, BMD was similar at activity beyond four times the minimum volume recommended in the Physical Activity Guidelines. These results suggest that the range of activity reported by US adults is not associated with low BMD at either site. ^ The American Heart Association / American College of Sports Medicine Preparticipation Questionnaire (AAPQ) was applied to 6,661 adults 40 years of age or older from NHANES 2001-2004 by using NHANES responses to complete AAPQ items. Following AAPQ referral criteria, 95.5% of women and 93.5% of men would be referred to a physician before exercise initiation, suggesting little utility for the AAPQ among adults aged 40 years or older. Unnecessary referral before exercise initiation may present a barrier to exercise adoption and may strain an already stressed healthcare infrastructure. ^ Among 3181 athletes in the Texas Adolescent Athlete Heart Screening Registry, 55.2% of boys and 62.2% of girls were classified as high-risk based on questionnaire answers. Using sex-stratified contingency table analyses, risk categories were not significantly associated with referral to physician based on electrocardiogram or echocardiogram, nor were they associated with confirmed diagnoses on follow-up. Additional research is needed to identify which symptoms are most closely related to sudden cardiac death, and determine the best methods for rapid and reliable assessment. ^ In conclusion, this research suggests that the volume of activity reported by US adults is not associated with low BMD at two clinically relevant sites, casts doubts on the utility of two existing cardiac screening tools, and raises concern about barriers to activity erected through ineffective screening. These findings augment existing research in this area that may inform revisions to the Physical Activity Guidelines regarding risk mitigation.^

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Multi-center clinical trials are very common in the development of new drugs and devices. One concern in such trials, is the effect of individual investigational sites enrolling small numbers of patients on the overall result. Can the presence of small centers cause an ineffective treatment to appear effective when treatment-by-center interaction is not statistically significant?^ In this research, simulations are used to study the effect that centers enrolling few patients may have on the analysis of clinical trial data. A multi-center clinical trial with 20 sites is simulated to investigate the effect of a new treatment in comparison to a placebo treatment. Twelve of these 20 investigational sites are considered small, each enrolling less than four patients per treatment group. Three clinical trials are simulated with sample sizes of 100, 170 and 300. The simulated data is generated with various characteristics, one in which treatment should be considered effective and another where treatment is not effective. Qualitative interactions are also produced within the small sites to further investigate the effect of small centers under various conditions.^ Standard analysis of variance methods and the "sometimes-pool" testing procedure are applied to the simulated data. One model investigates treatment and center effect and treatment-by-center interaction. Another model investigates treatment effect alone. These analyses are used to determine the power to detect treatment-by-center interactions, and the probability of type I error.^ We find it is difficult to detect treatment-by-center interactions when only a few investigational sites enrolling a limited number of patients participate in the interaction. However, we find no increased risk of type I error in these situations. In a pooled analysis, when the treatment is not effective, the probability of finding a significant treatment effect in the absence of significant treatment-by-center interaction is well within standard limits of type I error. ^

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This paper reports a cost-effectiveness analysis of standard therapeutic interventions received by ambulatory dually diagnosed clients of a Community Mental Health Center (CMHC). For the purposes of this study dually diagnosed was defined as a DSM-III-R or IV diagnosis of a major mental disorder and a concomitant substance abuse disorder. The prevalence of dually diagnosed people among the mentally ill and their unique and problematic nature continues to challenge and encumber CMHCs and poses grave public health risks. An absence of research on these clients in community-based settings and the cost-effectiveness of their standard CMHC care has hindered the development of effective community-based intervention strategies. This exploratory and descriptive effort is a first step toward providing information on which to base programmatic management decisions.^ Data for this study were derived from electronic client records of a CMHC located in a large Southwestern, Sun-belt metropolitan area. A total of 220 records were collected on clients consecutively admitted during a two-and-one-half year period. Information was gathered profiling the clients' background characteristics, receipt of standard services and treatments, costs of the care they received, and length of CMHC enrollment and subsequent psychiatric hospitalizations. The services and treatments were compared with regard to their costs and predicted contributions toward maintaining clients in the community and out of public psychiatric hospitals.^ This study investigated: (1) the study groups' background, mental illness, and substance abuse characteristics; (2) types, extent, and patterns of their receipt of standard services and treatments; (3) associations between the receipt of services and treatments, community tenure, and risk of psychiatric hospitalization; and, (4) comparisons of average costs for services and treatments in terms of their contributions toward maintaining the clients in the community.^ The results suggest that substance abuse and other lifestyle factors were related to the dually diagnosed clients' admissions to the CMHC. The dually diagnosed clients' receipt of care was associated strongly with their insurability and global functioning. Medication Services were the most expensive yet effective service or treatment. Supported Education was the third most expensive and second most effective. Psychosocial Services, the second most expensive, were only effective in terms of maintaining clients in the community. Group Counseling, the fourth most expensive, had no effect on community maintenance and increased the risk of hospitalization when accompanied by Medication Services. Individual Counseling, the least expensive, had no effect on community maintenance. But it reduced the risk of hospitalization when accompanied by Medication Services. Networking/Referral, the fifth most expensive service or treatment, was ineffective.^ The study compared the results with findings in the literature. Implications are discussed regarding further research, study limitations, practical applications and benefits, and improvements to theoretical understandings, in particular, concepts underscoring Managed Care. ^

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Nuevo paradigma para algunos, o simple eslogan político-mediático para otros, el concepto de desarrollo sustentable levanta reacciones contradictorias en el mundo científico. Existen notables diferencias en el acercamiento al desarrollo sustentable entre los representantes de las ciencias naturales y los de las ciencias humanas. El carácter nómada del concepto (Stengers, 1987) de desarrollo sustentable es percibido por ciertos investigadores en geografía como una verdadera tara genética, cuando otros piensan por el contrario que puede servir de palanca para renovar el acercamiento geográfico a los grandes problemas contemporáneos. ¿Para la investigación en geografía, qué postura es conveniente adoptar? ¿El desarrollo sustentable, como concepto nómada, puede convertirse en una herramienta eficaz e innovadora? ¿O bien su incertidumbre semántica nos conduce de manera inexorable hacia un vagabundeo de las ideas? El objetivo central de esta reflexión es intentar situar el concepto de desarrollo sustentable en la órbita del pensamiento geográfico, en una óptica comparativa con disciplinas vecinas y cuestionando a su vez su interés para la investigación en nuestro campo disciplinario. Para ello, es necesario en primer lugar acercarse sin tabúes a los problemas planteados por este concepto: ¿Debe considerarse el nomadismo conceptual del desarrollo sustentable como una especie de pecado original que lo convertiría en un instrumento inoperante para la geografía? En segundo lugar, desmitificando la novedad aparente del concepto, conviene analizar cuáles son sus filiaciones con la geografía y otras disciplinas. Y finalmente, plantear casos concretos de utilización del concepto en la investigación geográfica (ciudad sustentable; bosques sustentables), subrayando sus aportes, pero también poniendo a la luz sus límites.

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En este trabajo se exponen los resultados obtenidos en pruebas de germinación realizadas durante los años 1947, 1948 y 1949 de semillas de Gymnocladus dioica L. producidas en esta región, previamente tratadas con ácido sulfúrico concentrado (d. 1,84) . Estos ensayos fueron efectuados con el objeto de lograr una buena germinación, ya que la aplicación del tratamiento empleado por Wiesehugel (1935) resultó ineficaz. Los porcentajes más altos de germinación, 72% y 75%, se obtuvieron con inmerciones de las semillas en ácido, durante 16 y 18 horas.

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The ice cap on Berkner Island is grounded on bedrock within the Filchner-Ronne Ice Shelf and is, therefore, expected to be a well-suited place to retrieve long-term ice-core records reflecting the environmental situation of the Weddell Sea region. Shallow firn cores were drilled to 11 m at the two main summits of Berkner Island and analysed in high depth resolution for electrical d.c. conductivity (ECM), stable isotopes, chloride, sulphate, nitrate and methane-sulphonate (MSA). From the annual layering of dD and non-sea-salt (nss) sulphate, a mean annual snow accumulation of 26.6 cm water at the north dome and 17.4 cm water at the south dome are obtained. As a result of ineffective wind scouring indicated by a relatively low near-surface snow density, regular annual cycles are found for all species at least in the upper 4-5 m. Post depositional changes are responsible for a substantial decrease of the seasonal dD and nitrate amplitude as well as for considerable migration of the MSA signal operating below a depth of 3-4 m. The mean chemical and isotopic firn properties at the south dome correspond to the situation on the Filchner-Ronne Ice shelf at a comparable distance to the coast, whereas the north dome is found to be more influenced by maritime air masses. Persistent high sea-salt levels in winter snow at Berkner Island heavily obscure the determination of nss sulphate probably due to sulphate fractionation in the Antartic sea-salt aerosols. Estimated time-scales predict ages at 400 m depth to be ca. 2000 years for the north and ca. 3000 years for the south dome. Pleistocene ice is expected in the bottom 200 and 300 m, respectively.

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Rising levels of atmospheric carbon dioxide could be curbed by large-scale sequestration of CO2 in the deep sea. Such a solution requires prior assessment of the impact of hypercapnic, acidic seawater on deep-sea fauna. Laboratory studies were conducted to assess the short-term hypercapnic tolerance of the deep-sea Tanner crab Chionoecetes tanneri, collected from 1000 m depth in Monterey Canyon off the coast of central California, USA. Hemolymph acid- base parameters were monitored over 24 h of exposure to seawater equilibrated with ~1% CO2 (seawater PCO2 ~6 torr or 0.8 kPa, pH 7.1), and compared with those of the shallow-living Dungeness crab Cancer magister. Short-term hypercapnia-induced acidosis in the hemolymph of Chionoecetes tanneri was almost uncompensated, with a net 24 h pH reduction of 0.32 units and a net bicarbonate accumulation of only 3 mM. Under simultaneous hypercapnia and hypoxia, short-term extracellular acidosis in Chionoecetes tanneri was completely uncompensated. In contrast, Cancer magister fully recovered its hemolymph pH over 24 h of hypercapnic exposure by net accumulation of 12 mM bicarbonate from the surrounding medium. The data support the hypothesis that deep-sea animals, which are adapted to a stable environment and exhibit reduced metabolic rates, lack the short-term acid-base regulatory capacity to cope with the acute hypercapnic stress that would accompany large-scale CO2 sequestration. Additionally, the data indicate that sequestration in oxygen-poor areas of the ocean would be even more detrimental to deep-sea fauna.

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Ocean acidification has the potential to cause dramatic changes in marine ecosystems. Larval damselfish exposed to concentrations of CO2 predicted to occur in the mid- to late-century show maladaptive responses to predator cues. However, there is considerable variation both within and between species in CO2 effects, whereby some individuals are unaffected at particular CO2 concentrations while others show maladaptive responses to predator odour. Our goal was to test whether learning via chemical or visual information would be impaired by ocean acidification and ultimately, whether learning can mitigate the effects of ocean acidification by restoring the appropriate responses of prey to predators. Using two highly efficient and widespread mechanisms for predator learning, we compared the behaviour of pre-settlement damselfish Pomacentrus amboinensis that were exposed to 440 µatm CO2 (current day levels) or 850 µatm CO2, a concentration predicted to occur in the ocean before the end of this century. We found that, regardless of the method of learning, damselfish exposed to elevated CO2 failed to learn to respond appropriately to a common predator, the dottyback, Pseudochromis fuscus. To determine whether the lack of response was due to a failure in learning or rather a short-term shift in trade-offs preventing the fish from displaying overt antipredator responses, we conditioned 440 or 700 µatm-CO2 fish to learn to recognize a dottyback as a predator using injured conspecific cues, as in Experiment 1. When tested one day post-conditioning, CO2 exposed fish failed to respond to predator odour. When tested 5 days post-conditioning, CO2 exposed fish still failed to show an antipredator response to the dottyback odour, despite the fact that both control and CO2-treated fish responded to a general risk cue (injured conspecific cues). These results indicate that exposure to CO2 may alter the cognitive ability of juvenile fish and render learning ineffective.

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In Kazakhstan, uncover of numerous corruption scandals involving government officials has become almost a normal feature of life. Behind the high-profile acts of waging a battle against corruption, however, is a serious and systemic phenomenon. The most endemic form of corruption is the various transfers of funds in the state structures and national companies which remain opaque and thus unaccounted for. There are questions about the volumes and spending of revenues earned from natural resources, and there is no independent monitoring and control of the flow of funds in national oil and gas companies. The main actors involved in the shadow economy are state officials and informal pressure groups, who distribute resources among themselves, and accumulate wealth by way of legalising informal incomes or obtaining official business using connections. While important decision making is carried out among the close circles of the elite, formal institutions remain weak and ineffective.