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Damages caused by cotton rat, Sigmodon hispidus zanjonensis, on sugar cane in San Pedrosula, Honduras
Technical assistance was given to Compañía Azucarera Hondureña, S.A. (Agro-Industrial Co.), Honduras, Central America, to determine if a campaign against noxious rodents to agriculture crops was needed. Several trappings were carried out at different places using snap traps to determine the population structure of rodents associated with the crop, and live traps to determine the index or density of the Sigmodon hispidus rat population, which was identified as being responsible for the damage to sugarcane. Results were 43.24% adult males, 14.86% young males, 31.41% adult females, and 10.47% young females. Of the adult females captured, 54.83% were pregnant with an average of 3 to 4 embryos per rat. A control demonstration combat was carried out at one of the experimental stations with a bait prepared with 2% zinc phosphide in a place where it had been previously determined there was a population of 39 rats per hectare. After such control, the population was reduced to 18 rats per hectare, which represents an efficiency of 53.85%. An evaluation of damages was also measured at different places to determine the degree of loss caused by the rats, which proved to be 22.79% damage. The size of the sample was estimated in 3 samples per hectare, with a level of confidence of 95%
Building Energy System Design and Planning: The Universidad de Santander Case
Renewable generation is gaining more thrust as the time passes, however, the growth rate of such production has been faster than the rate of the electrical grid modernization. This growth comes with great opportunities and challenges for building energy system (BES) design and planning. In this respect, this paper presents the experience and lessons learned from the design and planning of the BES of the “Universidad de Santander” (UDES) central campus. This BES renewable generation is composed of a rooftop PV system distributed across the campus buildings. The system started with 30 kWp of installed capacity (100 kWh/day on average) and now is ready to deliver near 300 kWh/day thanks to 70 kWp of extra capacity installed. In general, the implementation has been a success that now is being replied in other UDES’ campuses, and the decision taking involved highlighted the importance of a proper energy efficiency policy and electrical regulation analysis
On the Past Asymptotic Dynamics of Non-minimally Coupled Dark Energy
We apply dynamical systems techniques to investigate cosmological models
inspired in scalar-tensor theories written in the Einstein frame. We prove that
if the potential and the coupling function are sufficiently smooth functions,
the scalar field almost always diverges into the past. The dynamics of two
important invariant sets is investigated in some detail. By assuming some
regularity conditions for the potential and for the coupling function, it is
constructed a dynamical system well suited to investigate the dynamics where
the scalar field diverges, i.e. near the initial singularity. The critical
points therein are investigated and the cosmological solutions associated to
them are characterized. We find that our system admits scaling solutions. Some
examples are taken from the bibliography to illustrate the major results. Also
we present asymptotic expansions for the cosmological solutions near the
initial space-time singularity, which extend in a way previous results of other
researchers.Comment: 38 pages, 2 figures, accepted for publication in CQ
Robotic Navigation based in Statics Patterns using the CMUcam3 Embedded System
Este artículo presenta un método de navegación Robótico basado en patrones estáticos usando técnicas de visión artificial implementadas sobre el sistema embebido CMUcam3, además presenta un análisis de procesamiento de cómputo para este sistema embebido. El patrón a determinar es una línea negra con cruces, guiando al agente robótico a través de ésta. Luego de la adquisición de las imágenes mediante la CMUcam3, se utiliza un algoritmo de segmentación basado en umbral, se determina el esqueleto de los patrones y luego se aplica la transformada de Hough lineal para determinar, las líneas, los ángulos y los tipos de cruces. Debido a que la transformada de Hough lineal es un método que requiere alto procesamiento, en este trabajo, se limita el rango de los ángulos y se normaliza su espacio de acumulaciones. En los resultados obtenidos se pudo determinar que el método desarrollado para la navegación es preciso y confiable, ya que en un 87% de los segmentos de decisión se pudo determinar correctamente el tipo de cruce y el ángulo de corrección. Él sistema embebido CMUcam3 logró procesar una imagen entre 0.15 y 0.28 segundos, dependiendo del tipo de cruce que encuentre.This paper presents a method based on static patterns for robotic navigation using computer vision techniques implemented on CMUcam3 embedded system, also presents an analysis of computational complexity for this embedded system. The pattern to be determined is a black line with intersections, driving the robotic agent over the line. A segmentation algorithm based in threshold is used after the images acquisition by the CMUcam3, then defines the thinning patterns and then the linear Hough transform is applied to determine the lines, the angles and the type of the intersections. Due to the linear Hough transform is a method that requires high processing, in this project, the range of the angles are limited and the accumulation space is normalized. The results showthat the method developed for the navigation is accurate and reliable, because in 87% of the decision segments it could determine correctly the type of intersection and the correction angle. The CMUcam3 embedded system succeeded to process an image between 0.15 and 0.28 seconds, depending of the type of the intersection
Qualitative properties of scalar-tensor theories of Gravity
The qualitative properties of spatially homogeneous stiff perfect fluid and
minimally coupled massless scalar field models within general relativity are
discussed. Consequently, by exploiting the formal equivalence under conformal
transformations and field redefinitions of certain classes of theories of
gravity, the asymptotic properties of spatially homogeneous models in a class
of scalar-tensor theories of gravity that includes the Brans-Dicke theory can
be determined. For example, exact solutions are presented, which are analogues
of the general relativistic Jacobs stiff perfect fluid solutions and vacuum
plane wave solutions, which act as past and future attractors in the class of
spatially homogeneous models in Brans-Dicke theory.Comment: 19 page
Additional chromosome abnormalities in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and chemotherapy
Background Acute promyelocytic leukemia is a subtype of acute myeloid leukemia characterized by the t(15;17). The incidence and prognostic significance of additional chromosomal abnormalities in acute promyelocytic leukemia is still a controversial matter. Design and Methods Based on cytogenetic data available for 495 patients with acute promyelocytic leukemia enrolled in two consecutive PETHEMA trials (LPA96 and LPA99), we analyzed the incidence, characteristics, and outcome of patients with acute promyelocytic leukemia with and without additional chromosomal abnormalities who had been treated with all-trans retinoic acid plus anthracycline monochemotherapy for induction and consolidation. Results Additional chromosomal abnormalities were observed in 140 patients (28%). Trisomy 8 was the most frequent abnormality (36%), followed by abn(7q) (5%). Patients with additional chromosomal abnormalities more frequently had coagulopathy (P=0.03), lower platelet counts (P=0.02), and higher relapse-risk scores (P=0.02) than their counterparts without additional abnormalities. No significant association with FLT3/ITD or other clinicopathological characteristics was demonstrated. Patients with and without additional chromosomal abnormalities had similar complete remission rates (90% and 91%, respectively). Univariate analysis showed that additional chromosomal abnormalities were associated with a lower relapse-free survival in the LPA99 trial (P=0.04), but not in the LPA96 trial. However, neither additional chromosomal abnormalities overall nor any specific abnormality was identified as an independent risk factor for relapse in multivariate analysis. Conclusions The lack of independent prognostic value of additional chromosomal abnormalities in acute promyelocytic leukemia does not support the use of alternative therapeutic strategies when such abnormalities are found
Neumotórax espontáneo idiopático secundario a neumotórax catamenial no asociado a endometriosis: reporte de caso
El neumotórax espontáneo idiopático constituye una causa poco frecuente de neumotórax, si se le atribuyen causas no pulmonares como el neumotórax catamenial y/o neumotórax catamenial no asociado a endometriosis, esta condición se hace aún más rara. El abordaje terapéutico está en estrecha relación al control de las complicaciones generadas por el neumotórax. Se presenta a continuación el caso de una paciente femenina de 34 años, quien debuta con su primer episodio de neumotórax espontáneo, el cual se presume a características catameniales por la coincidencia con el ciclo menstrual de la misma
Neumotórax espontáneo idiopático secundario a neumotórax catamenial no asociado a endometriosis: reporte de caso
Idiopathic spontaneous pneumothorax is a rare cause of pneumothorax, if non-pulmonary causes such as catamenial pneumothorax and/or catamenial pneumothorax not associated with endometriosis are attributed to it, this condition becomes even rarer. The therapeutic approach is closely related to the control of the complications generated by the pneumothorax. The following is the case of a 34-year-old female patient, who debuts with her first episode of spontaneous pneumothorax, which is presumed to have catamenial characteristics due to the coincidence with her menstrual cycle.El neumotórax espontáneo idiopático constituye una causa poco frecuente de neumotórax, si se le atribuyen causas no pulmonares como el neumotórax catamenial y/o neumotórax catamenial no asociado a endometriosis, esta condición se hace aún más rara. El abordaje terapéutico está en estrecha relación al control de las complicaciones generadas por el neumotórax. Se presenta a continuación el caso de una paciente femenina de 34 años, quien debuta con su primer episodio de neumotórax espontáneo, el cual se presume a características catameniales por la coincidencia con el ciclo menstrual de la misma
Cruciate-Retaining vs Posterior-Stabilized Primary Total Arthroplasty. Clinical Outcome Comparison With a Minimum Follow-Up of 10 Years
Background: Controversy continues regarding whether the posterior cruciate ligament should be retained or removed during total knee arthroplasty (TKA) procedure. The objective was to compare the clinical outcomes with a minimum follow-up of 10 years between patients who received contemporary cruciate-retaining or posterior-stabilized primary TKA. Methods: Case-control study of 268 patients who underwent cruciate-retaining TKA vs 211 to posterior-stabilized design, with the same arthroplasty system, and a minimum follow-up of 10 years. Clinical assessment was performed by Knee Society scores, Western Ontario and MacMasters Universities and Short-Form 12 questionnaires, range of motion, and patient satisfaction. Results: Successful outcomes were found for both designs. No significant differences in functional scores, range of motion, patient-related scores, or patient satisfaction. Between the 5-year and last postoperative follow-up, there were a significant decrease of all clinical scores in both groups. In addition, complication rate and implant survival were similar between groups. Conclusion: The superiority of one design over the other was not found. Both designs can be used expecting long-term successful outcomes and high survival. The choice of the design depended on the status of the posterior cruciate ligament and surgeon preference
Relationship between cognition and age at onset of first-episode psychosis: comparative study between adolescents, young adults, and adults
Psychotic disorders typically manifest from late adolescence to early adulthood, and an earlier onset might be associated with greater symptom severity and a worse long-term prognosis. This study aimed to compare the cognitive characteristics of patients with first-episode psychosis (FEP) by their age at onset. We included 298 patients diagnosed with FEP and classified them as having an early onset (EOS), youth onset (YOS), or adult onset (AOS) based on age limits of = 25 years (N = 116), respectively. Socio-demographic and clinical variables included age at baseline, gender, socio-economic status, antipsychotic medication, DSM-IV diagnoses assessed by clinical semi-structured interview, psychotic symptom severity, and age at onset. Neuropsychological assessment included six cognitive domains: premorbid intelligence, working memory, processing speed, verbal memory, sustained attention, and executive functioning. The EOS group had lower scores than the YOS or AOS groups in global cognition, executive functioning, and sustained attention. Although the scores in the YOS group were intermediate to those in the EOS and AOS groups for most cognitive factors, no statistically significant differences were detected between the YOS and AOS groups. Age at onset results in specific patterns of cognitive interference. Of note, impairment appears to be greater with EOS samples than with either YOS or AOS samples. A longitudinal study with a larger sample size is needed to confirm our findings
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