1,361 research outputs found
Phototube tests in the MiniBooNE experiment
The MiniBooNE neutrino oscillation experiment at Fermilab uses 1520 8-inch
PMTs: 1197 PMTs are Hamamatsu model R1408 and the rest are model R5912. All of
the PMTs were tested to qualify for inclusion in the detector, sorted according
to their charge and time resolutions and dark rates. Seven PMTs underwent
additional low light level tests. The relative detection efficiency as a
function of incident angle for seven additional PMTs was measured. Procedures
and results are presented.Comment: 4 pages, 7 figures. Presented at Beaune 2005: 4th International
Conference on New Developments in Photodetection, Beaune, France, 19-24 June
200
Influence of the asexual parasite biomass on in vitro susceptibility of Plasmodium falciparum to antimalarial drugs in Abidjan
The in vitro activities of artemisinin, dihydroartemisinin (the biologically active metabolite of artemisinin derivatives), chloroquine and pyronaridine were assessed in 32 isolates of Plasmodium falciparum from Abobo in the northern of Abidjan district (Cote dfIvoire) using a test based on the standard microtechnique recommended by the World Health Organization (WHO). The parasites densities were ranged between 8,000 and 540,000 rings/ƒÊl of blood. The geometric means 50% inhibitory concentration (GMIC50) values for chloroquine, pyronaridine and artemisinin were 145.5 nM (95% confidence interval (CI) =65-226 nM), 17.69 nM (95% CI=9.1-26.3 nM) and 5.72 nM (95% CI=2.3-9.1 nM), respectively. Dihydroartemisinin was the most potent drug against chloroquine-sensitive and chloroquine-resistant isolates with a geometric mean of 2.72 nM. There was no correlation between the parasite densities and the responses to chloroquine (r2=0.01, p<0.5), pyronaridine (r2=0.13, p<0.05), artemisinin (r2=0.13, p<0.05) and dihydroartemisinin (r2=0.07, p<0.1)
When Do Security Markets Aggregate Dispersed Information?
We attempt to replicate a seminal paper that offered support for the rational expectations hypothesis and reported evidence that markets with certain features aggregate dispersed information. The original results are based on only a few observations, and our attempt to replicate the key findings with an appropriately powered experiment largely fails. The resulting poststudy probability that market performance is better described by rational expectations than the prior information (Walrasian) model under the conditions specified in the original paper is very low. As a result of our failure to replicate, we investigate an alternate set of market features that combines aspects of the original experimental design. For these markets, which include both contingent claims and homogeneous dividend payments (as in many prediction markets), we do find robust evidence of information aggregation in support of the rational expectations model. In total, our results indicate that information aggregation in asset markets is fragile and should only be expected in limited circumstances
Reconsidering Rational Expectations and the Aggregation of Diverse Information in Laboratory Security Markets
The ability of markets to aggregate diverse information is a cornerstone of economics and finance, and empirical evidence for such aggregation has been demonstrated in previous laboratory experiments. Most notably Plott and Sunder (1988) find clear support for the rational expectations hypothesis in their Series B and C markets. However, recent studies have called into question the robustness of these findings. In this paper, we report the result of a direct replication of the key information aggregation results presented in Plott and Sunder. We do not find the same strong evidence in support of rational expectations that Plott and Sunder report suggesting information aggregation is a fragile property of markets
Reconsidering Rational Expectations and the Aggregation of Diverse Information in Laboratory Security Markets
The ability of markets to aggregate dispersed information is a cornerstone of economics and finance. In a seminal experiment, Plott and Sunder (1988) offer support for the rational expectations hypothesis. However, recent laboratory experiments have called into question the robustness of those initial results. In this paper, we offer the first attempt to directly replicate key findings of the original study. Failing to replicate their results, the post-study probability that market performance is better described by rational expectations than the prior information (Walrasian) model is low. Given this result, we introduce a new treatment that implements a market structure consistent with naturally occurring prediction markets, which can be viewed as completing the original experimental design. In this new treatment, we find strong support for the rational expectations model. Thus, while the original paper showed conditions where markets can aggregate information, we attempt to identify sufficient conditions for such aggregation to be robust
Factores que inciden en la convivencia escolar en la sede 02 concentraci?n de desarrollo rural ?La Granja? de la Instituci?n Educativa T?cnica los Andes del municipio de Planadas Tolima
289 p. Recurso Electr?nicoLa investigaci?n ten?a como prop?sito evidenciar los factores que afectan la convivencia
escolar en la comunidad educativa Sede 02 ?La Granja? Instituci?n Educativa T?cnica
Los Andes Municipio de Planadas Tolima; determinados permitieron la creaci?n e
implementaci?n de una estrategia que con la ayuda de unas herramientas digitales
contribuir?n al fortalecimiento de la convivencia escolar, hacia el ejercicio real y efectivo
de los derechos humanos.
Por lo anterior la investigaci?n se fundament? en el dise?o cualitativo, apoyada en
encuestas y entrevistas semiestructuradas, las cuales miraron la problem?tica desde
aspectos sociales, culturales y pedag?gicos, que permitieron establecer las situaciones
m?s relevantes de la convivencia en la sede motivo de estudio, a su vez originaron las
conclusiones que dar?an luces a la soluci?n de una problem?tica socio-educativa.
Palabras Clave: Investigaci?n, Convivencia Escolar, Integridad.The purpose of the research was to highlight the factors that affect school coexistence in
the educational community Headquarters 02 "La Granja" Los Andes Technical
Educational Institution Municipality of Planadas Tolima; determined allowed the creation
and implementation of a strategy that with the help of digital tools will contribute to the
strengthening of school coexistence, towards the real and effective exercise of human
rights.
Therefore, the research was based on qualitative design, supported by surveys and semistructured
interviews, which looked at the problem from social, cultural and pedagogical
aspects, which allowed to establish the most relevant situations of coexistence in the field
of study, they originated the conclusions that would shed light on the solution of a socioeducational
problem.
Keywords: Research, School Coexistence, Integrity
Patient-Specific Surgical Correction of Adolescent Idiopathic Scoliosis: A Systematic Review
The restoration of sagittal alignment is fundamental to the surgical correction of adolescent idiopathic scoliosis (AIS). Despite established techniques, some patients present with inadequate postoperative thoracic kyphosis (TK), which may increase the risk of proximal junctional kyphosis (PJK) and imbalance. There is a lack of knowledge concerning the effectiveness of patient-specific rods (PSR) with measured sagittal curves in achieving a TK similar to that planned in AIS surgery, the factors influencing this congruence, and the incidence of PJK after PSR use. This is a systematic review of all types of studies reporting on the PSR surgical correction of AIS, including research articles, proceedings, and gray literature between 2013 and December 2023. From the 28,459 titles identified in the literature search, 81 were assessed for full-text reading, and 7 studies were selected. These included six cohort studies and a comparative study versus standard rods, six monocentric and one multicentric, three prospective and four retrospective studies, all with a scientific evidence level of 4 or 3. They reported a combined total of 355 AIS patients treated with PSR. The minimum follow-up was between 4 and 24 months. These studies all reported a good match between predicted and achieved TK, with the main difference ranging from 0 to 5 degrees, p > 0.05, despite the variability in surgical techniques and the rods' properties. There was no proximal junctional kyphosis, whereas the current rate from the literature is between 15 and 46% with standard rods. There are no specific complications related to PSR. The exact role of the type of implants is still unknown. The preliminary results are, therefore, encouraging and support the use of PSR in AIS surgery
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