Decays Z' -> \gamma\gamma\gamma{} and Z -> \gamma\gamma\gamma{} in the minimal 331 model

The possibility of a significant effect of exotic particles on the Z'->\gamma\gamma\gamma{} and Z->\gamma\gamma\gamma{} decays is investigated in the context of the minimal 331 model. This model, which is based in the SU_C(3)xSU_L(3)xU_X(1) gauge group, predicts the existence of many exotic charged particles that can significantly enhance the decay widths. It is found that the standard model prediction for the Z->\gamma\gamma\gamma{} decay remains essentially unchanged, as the new physics effects quickly decouples. On the other hand, it is found that the contributions of the new exotic quarks and gauge bosons predicted by this model lead to a branching fraction for the Z'->\gamma\gamma\gamma{} decay of about 10^(-6), which is about three orders of magnitude larger than that of the Z->\gamma\gamma\gamma{} decay.Comment: 20 pages and 20 figure

Bilepton effects on the WWV^* vertex in the 331 model with right-handed neutrinos via a SU_L(2)XU_Y(1) covariant quantization scheme

In a recent paper, we investigated the effects of the massive charged gauge bosons (bileptons) predicted by the minimal 331 model on the off-shell vertex WWV^* (V=gamma, Z) using a SU_L(2) X U_Y(1) covariant gauge-fixing term for the bileptons. We proceed along the same lines and calculate the effects of the gauge bosons predicted by the 331 model with right-handed neutrinos. It is found that the bilepton effects on the WWV^* vertex are of the same order of magnitude than those arising from the SM and several of its extensions, provided that the bilepton mass is of the order of a few hundred of GeVs. For heavier bileptons, their effects on the WWV^* vertex are negligible. The behavior of the form factors at high energies is also discussed as it is a reflect of the gauge invariance and gauge independence of the WWV^* Green function obtained via our quantization method.Comment: Replaced to match published versio

Understanding atrioventricular septal defect: Anatomoechocardiographic correlation

<p>Abstract</p> <p>Objective</p> <p>Correlate the anatomic features of atrioventricular septal defect with echocardiographic images.</p> <p>Materials and methods</p> <p>Sixty specimen hearts were studied by sequential segmental analysis. Echocardiograms were performed on 34 patients. Specimen hearts with findings equivalent to those of echocardiographic images were selected in order to establish an anatomo-echocardiographic correlation.</p> <p>Results</p> <p>Thirty-three specimen hearts were in situs solitus, 19 showed dextroisomerism, 6 were in situs inversus and 2 levoisomerism. Fifty-eight had a common atrioventricular valve and 2 had two atrioventricular valves. Rastelli types were determined in 21 hearts. Nine were type A, 2 intermediate between A and B, 1 mixed between A and B, 4 type B and 5 type C. Associated anomalies included pulmonary stenosis, pulmonary atresia atrial septal defect, patent ductus arteriosus and anomalous connection of pulmonary veins. Echocardiograms revealed dextroisomerism in 12 patients, situs solitus in 11, levoisomerism in 7 and situs inversus in 4. Thirty-one patients had common atrioventricular valves and three two atrioventricular valves. Rastelli types were established in all cases with common atrioventricular valves; 17 had type A canal defects, 10 type B, 3 intermediate between A and B, 1 mixed between A and B and 3 type C. Associated anomalies included regurgitation of the atrioventricular valve, pulmonary stenosis, anomalous connection of pulmonary veins, pulmonary hypertension and pulmonary atresia.</p> <p>Conclusion</p> <p>Anatomo-echocardiographic correlation demonstrated a high degree of diagnostic precision with echocardiography.</p

Carrageenan from Chondracanthus Chamissoi Algae: Extraction process and experimental evaluation as green corrosion inhibitor for P22 steel in HCl

In this study, the extraction yield of carrageenan from the algae Chondracanthus Chamissoi and its efficiency as an ecological corrosion inhibitor for P22 steel in 1 M HCl at 65°C were evaluated. The extraction of carrageenan from the algae Chondracanthus chamissoi was carried out in cold water at 25°C (CC) and hot water at 80°C (HC), with different degreasing stages prior to the extraction (0, 1 and 2 stages). The codes of the six samples of carrageenan obtained were selected in terms of the production temperature and degreasing stages as: CC-0, CC-1, CC-2, HC-0, HC-1 and HC-2. All the carrageenan samples were characterized using: Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy and energy dispersive spectrum. The CC shows crystallinity and is mainly composed of κ-carrageenan in the presence of KCl, NaCl and K3Na(SO4)2; while the degreasing stages reduce the content of KCl and NaCl. The HC presents an amorphous structure composed of κ/ι carrageenans. The highest carrageenan extraction yielded in cold water was 21.43%, without the degreasing stage (CC-0); while, the highest carrageenan extraction yielded in hot water was 28.96% with 2 degreasing stages (HC-2). The inhibition performance was investigated using gravimetric analysis, potentiodynamic polarization, linear polarization resistance, electrochemical impedance spectroscopy and electrochemical frequency modulation. The experimental results demonstrated that all six carrageenan inhibitors act as good corrosion inhibitors for P22 steel in 1 M HCl at 65°C. However, the CC-0 presented the maximum corrosion inhibition efficiency (IEc) of 85.53% (EIS technique). In the HC, the degrease does not significantly affect IEc, allows to obtain 82.56% without degrease (EIS technique). Based on the results obtained, the extraction CC-0 and HC-0 in the same extraction process, allows to obtain a semi-refined, economical carrageenan, with a total carrageenan yield of 45.91%, and with a high IEc.Fil: Zavaleta Gutiérrez, N.. Universidad Nacional de Trujillo.; PerúFil: Alvarado Loyola, L.. Universidad Nacional de Trujillo.; PerúFil: Angelats Silva, L.. Universidad Privada Atenor Orrego; PerúFil: Ñique Gutierrez, N.. Universidad Nacional de Trujillo.; PerúFil: Duffó, Gustavo Sergio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica; Argentina. Universidad Nacional de San Martín; Argentin

One-loop effects of extra dimensions on the WW\gamma and WWZ vertices

The one-loop contribution of the excited Kaluza-Klein (KK) modes of the $SU_L(2)$ gauge group on the off-shell $WW\gamma$ and $WWZ$ vertices is calculated in the context of a pure Yang-Mills theory in five dimensions and its phenomenological implications discussed. The use of a gauge-fixing procedure for the excited KK modes that is covariant under the standard gauge transformations of the $SU_L(2)$ group is stressed. A gauge-fixing term and the Faddeev-Popov ghost sector for the KK gauge modes that are separately invariant under the standard gauge transformations of $SU_L(2)$ are presented. It is shown that the one-loop contributions of the KK modes to the off-shell $WW\gamma$ and $WWZ$ vertices are free of ultraviolet divergences and well-behaved at high energies. It is found that for a size of the fifth dimension of $R^{-1}\sim 1TeV$, the one-loop contribution of the KK modes to these vertices is about one order of magnitude lower than the corresponding standard model radiative correction. This contribution is similar to the one estimated for new gauge bosons contributions in other contexts. Tree-level effects on these vertices induced by operators of higher canonical dimension are also investigated. It is found that these effects are lower than those generated at the one-loop order by the KK gauge modes.Comment: 19 pages, 9 figures. Some typos were correcte

Performance of Dual-Purpose Cows on a Native Pasture-\u3ci\u3eArachis pintoi\u3c/i\u3e Association in the Humid Tropics of Mexico

Native grasslands (NG) are the main feed supply of dual-purpose (DP) cows of the Mexican humid tropics. NG comprise about 85% of Paspalum, Axonopus and Cynodon species, about 5% of native legumes, mainly of Desmodium, and the remaining 10% are narrow and broad leafed weeds. Arachis pintoi (AP) is a persistent grazing tolerant tropical legume. In association with sown grasses, it has improved dry matter (DM) yield, nutritive quality of forage, and milk yield up to 9 kg/cow/day (González et al., 1996). The objective was to determine if productive performance of DP cows could be improved by the introduction of AP into NG grassland

Economically Optimum Irrigation Patternsfor Grain Sorghum Production: Texas High Plains

Agricultural production and associated economic effects of irrigation on the Texas High Plains are seriously threatened by a rapidly declining groundwater supply and a swift upward trend in energy costs. To optimize the amount of irrigation water to be applied during specified periods of the production process, a stochastic open-loop feedback control policy was built into a grain sorghum growth simulation model. The control policy operated under the basis of constant revision of the expectations generated at every starting point for each of the production periods. If discrepancies between the expected and the realized values existed, then, based on current conditions a reevaluation of the control variable, irrigation water, was made and the decision for the first period adopted. This process continued throughout each period of the growing season. Within the stochastic policy designed, the values for the control variable were obtained by numerical search. The model was applied to estimate optimal irrigation strategies and the impact of fuel curtailments on them. Initially, optimal irrigation strategies were developed under the assumption of perfect knowledge. Under this assumption, the results indicated there was not a unique strategy to be applied at all times. The quantities of irrigation water to apply at each period depended on the initial or starting conditions. Since one of the purposes of building the model was to make it perform under stochastic or real world conditions, the assumption of complete knowledge was relaxed to consider the case where the climatic environment was unknown. As in the deterministic case, the optimal amounts of irrigation water, by period. It was also observed, that with the open-loop feedback control, the results obtained for yields did not differ substantially from those obtained in the perfect knowledge case. The discrepancies among the two cases were primarily in the optimal amount of water applied and therefore in net returns. In the stochastic case, the use of irrigation water had a mean value approximately 25 percent more than in the case of perfect knowledge. The effect of a fuel or irrigation curtailment was estimated for alternative time spans. When curtailments had a length of 10 days, there were no perceptible changes in the amount of net returns or yields, as compared to the no-curtailment case. The implication drawn was that by having frequent irrigation periods and applying optimal amounts of water, the adverse effects of 10-day curtailment periods were buffered. The cases of twenty and thirty-day periods were found to have highly negative effects on the outcomes, especially net revenues, which decreased about 50 percent (from $99 to$50) in the curtailment case of 40 - 70 days after plant emergence compared to the no-curtailment value. The effects were not only on a decreased amount of returns perceived but also on an increased spectrum of relative fluctuation (from 18 percent to 68 percent for the same situations mentioned above). It was also found that for the same time-span type of curtailments the effects were conditioned to the period in which they Occurred. However, the 20 or 30 day curtailment period might be applicable to much shorter actual fuel curtailment periods. Producers lose not only the time of fuel curtailments, but also, they must cover many acres with a limited number of wells. As a result, a 10-day fuel curtailment could easily result in a 20 to 30 day delayed irrigation. To summarize, improved irrigation distribution technology could result in increased yields and less irrigation water by simply having very close control on timing and quantity of water applied

The State of Capacity Development Evaluation in Biodiversity Conservation and Natural Resource Management

Capacity development is critical to long-term conservation success, yet we lack a robust and rigorous understanding of how well its effects are being evaluated. A comprehensive summary of who is monitoring and evaluating capacity development interventions, what is being evaluated and how, would help in the development of evidence-based guidance to inform design and implementation decisions for future capacity development interventions and evaluations of their effectiveness. We built an evidence map by reviewing peer-reviewed and grey literature published since 2000, to identify case studies evaluating capacity development interventions in biodiversity conservation and natural resource management. We used inductive and deductive approaches to develop a coding strategy for studies that met our criteria, extracting data on the type of capacity development intervention, evaluation methods, data and analysis types, categories of outputs and outcomes assessed, and whether the study had a clear causal model and/or used a systems approach. We found that almost all studies assessed multiple outcome types: most frequent was change in knowledge, followed by behaviour, then attitude. Few studies evaluated conservation outcomes. Less than half included an explicit causal model linking interventions to expected outcomes. Half of the studies considered external factors that could influence the efficacy of the capacity development intervention, and few used an explicit systems approach. We used framework synthesis to situate our evidence map within the broader literature on capacity development evaluation. Our evidence map (including a visual heat map) highlights areas of low and high representation in investment in research on the evaluation of capacity development

Efectividad de cepas de Aspergillus y Penicillium en la degradación de polietileno de baja densidad aislados en los botaderos de los Distritos de Sicuani y Calca- Cusco.

Se evaluó la eficiencia de degradación de Polietileno de baja densidad por cepas de Aspergillus y Penicillium,aislados de los botaderos de los distritos de Calca y Sicuani- Cusco. &nbsp;Para el aislamiento de hongos de residuos de plástico, se utilizó el método por incrustación, la identificación taxonómica de las cepas se realizó utilizando el sistema de identificación para especies de Aspergillus y Penicillium propuesto por Pitt. La concentración de esporas y la actividad degradadora de polietileno se determinó por el Método de Kavelman. &amp; Kendrick. Se aislaron 7 cepas degradadoras de polietileno, de las cuales 4 corresponden a Aspergillus flavus, y 1 cepa a Penicillium sp, proveniente del botadero de Sicuani; 2 cepas a Aspergillus terreus aisladas del botadero de Calca. Las cepas más eficientes en degradación de polietileno fueron 3AS y 3BS aisladas de superficie con 50 y 29 % de eficiencia y la cepa 1BS aislada a 50 cm de profundidad con una eficiencia de degradación de 29 %, todas pertenecen a la especie de Aspergillus flavus, la cepa 2AS de Penicillium sp, se aisló a 50 cm de profundidad, con 15 % de eficiencia, aisladas del botadero de Sicuani. &nbsp;Las cepas 1AC, 1EC de Aspergillus terreus, con 15 y 17 % de eficiencia, fueron aisladas de superficie del botadero de Calca respectivamente. &nbsp;El Consorcio I constituido por 3 cepas de Aspergillus flavus fue el más eficiente degradando 44.3 % de polietileno, los consorcios II y III presentaron la misma eficiencia de degradación estadísticamente con 26 y 19 %

A GLOBAL ANALYSIS OF THE INFLUENCE OF GOVERNANCE ON IMPROVING TOURISM COMPETITIVENESS

Objective: The objective of the study was to identify the influence of governance on tourism competitiveness as measured by tourism GDP per capita, using structural equation modeling.Methodology: The study was descriptive correlational and applied quantitative documentary approach. Data from secondary sources from the World Bank and The World Travel & Tourism were used to obtain measures of governance and tourism GDP for 172 countries during the year 2021.Results: Governance was found to have a significant influence on tourism competitiveness, with government effectiveness, regulatory quality and rule of law emerging as the main predictors of governance. It was also found that most countries with high tourism performance have good governance, especially those countries that are small and specialized in tourism. Developed countries enjoy a high governance index, but do not lead the ranking in tourism GDP per capita.  Countries with low tourism performance have poor governance.Conclusions: Governance is a crucial factor in the success or failure of the tourism sector, and the positive and significant relationship between governance and tourism competitiveness has important implications for the formulation of policies and strategies to promote sustainable tourism development