Search for a Standard Model Higgs in the mass range 200--600 GeV in the channel H→ZZ→ℓ+ℓ−qq¯ with the ATLAS detector

We describe the searches for a Standard Model (SM) Higgs boson in the channel H → ZZ → + −qq¯ ( = e, μ), in the range 200–600 GeV, using 4.71 fb−1 of pp collision data collected by the ATLAS experiment at √s = 7 TeV taken in 2011. Events with two b-tagged jets, which have a better signal-tobackground ratio, are treated as a separate channel. No significant excess of events above the estimated background is found and upper limits at 95% confidence level (CL) on the production cross section (relative to that expected from the Standard Model) of the Higgs boson with a mass in the range between 200 and 600 GeV are derived

Assessing land use/cover change in Costa Rica

The need for accurate estimates of forest cover and forest fragmentation is a critical issue for developing countries such as Costa Rica. Accurate estimates of forest cover can help in several sectors related to the environment and economic development. This dissertation focuses on providing an accurate and precise estimate of forest cover in Costa Rica. The year 1991 was used as a baseline. Landsat Thematic Mapper was the remote sensing sensor used in this analysis. This dissertation concludes that: (1) Twenty-nine percent ($\sim$1,400,000 ha) of the country was under primary forest (80% canopy closure) in 1991. Of the total forest cover, 71% is outside national parks and 29% is protected by the national parks. (2) Forest loss (for scene path 15/row 53) during five years period (1986-1991) was 224,970 ha, and it was estimated that the rate was $\sim$44,994 ha/yr. (3) Deforestation produced an increase in island fragments during the study period. Between 1986 and 1991, the total number of islands between three and 50 ha, and 50 and 100 ha increased by 524 and 45, respectively. Fifteen new islands with areas greater than 500 ha were created. (4) Results suggest that the extent of tropical deforestation go beyond estimations of total forest loss at the national level. The impacts at the national level have greater roots deeper roots when the data at the life zone level is considered. The results have important implication for biodiversity conservation and restoration, water resource management and climate change. The issue of partial sampling of remote sensing data base was also explored through this dissertation. Partial sampling is important for the definition of sound deforestation monitoring systems in tropical environments. A data set from the Brazilian Amazon was analyzed in order to understand how stratified sampling, using persistence, would improve estimates of tropical deforestation over random sampling. Results show that stratification based on persistence contributes to the reduction of error, regarding estimates of total deforestation, when contrasted against random sampling without stratification (FAO methodology). Results are important to future monitoring programs in Costa Rica and the Central American region

The Public Institutiones Of Higher Education: Analysis Of The Factors That Affects The Educational System

En la presente investigación se retoma la teoría de la motivación humana que propone jerarquías de las necesidades, puesto que los seres humanos son motivados por necesidades múltiples y que solo existen en un orden jerárquico. Sin embargo, en las instituciones Públicas de Educación Superior en México, no hay resultados contundentes de la aplicación de esta teoría, ya que las áreas de oportunidad en el factor de motivación refleja que el personal que labora en estas instituciones no es se siente motivado por el trabajo que desempeña. Se analizaron siete instituciones de educación superior donde se encuestaron 224 sujetos divididos en directivo, mandos medios y personal operativo, en los subsistemas de educación Tecnológicas, Autónomas, Politécnicas, Tecnológicos de Estudios Superiores e Institutos Tecnológicos Superiores, en los estados de México, Puebla e Hidalgo. Considerando los factores de comunicación, motivación, satisfacción laboral, identidad, trabajo en equipo y liderazgo. Se logró comprobar la hipótesis estadística planteada, para lo cual se analizaron los factores de comunicación, motivación, satisfacción laboral, identidad, trabajo en equipo y liderazgo en los directivos, mandos medios y personal operativo. A partir de lo anterior, se acepta la hipótesis alternativa, es decir, que existe correlación significativa entre todas las variables estudiadas y se puede afirmar que son generalizables para toda la población.The purpose of the present research is to study the effects of statistical data on the behavior of Higher Education Faculties (IPES) in some states of the Mexican Republic. According to the ANUIES (2012) data base, in Hidalgo State 17% of students concluded their career, while 10.7% is graduated, this is associated that some students delay the academic process. In Mexico State 14.4% students complete the higher studies, but only 74.25% obtain their professional grade. Puebla indicates that 18% finished their studies and only 76% are graduated. Therefore, the most outstanding problems in higher education are the following situations: • Inequity in access to the detriment of young people from low economic status. • Limited relations with industrial-productive areas. • Discrepancy with other educational levels. • Insufficient economical support for research in public Universities and restricted relationship with the science and technology system. • Weak relevance and quality. • Growth of student population in higher institutions. Finally, the problematic considers that IPES has influences in the commitment of human resource to improve the results of the academic institutions, since in the higher education is one of the main factors in the educational process. Within the functional areas of the IPES, the main component to be studied is the academic employees, who provide the institution with knowledge, skills, abilities and capacities, which become human resource advantages; In return for this, the employees obtain benefits of salary, rewards, gratuities and promotions, therefore the degree of satisfaction increases its disposition when maintaining lines of activity with the educational organization. In this relationship of economic-social interchange the norm of reciprocity and variables such as communication, motivation, job satisfaction, identity, teamwork and leadership, so the degree of employee satisfaction generates a sense of belonging that favors the achievement of organizational objectives

Contribution of Lianas to Plant Area Index and Canopy Structure in A Panamanian Forest

Lianas are an important component of tropical forests, where they reduce tree growth, fecundity, and survival. Competition for light from lianas may be intense; however, the amount of light that lianas intercept is poorly understood. We used a large-scale liana-removal experiment to quantify light interception by lianas in a Panamanian secondary forest. We measured the change in plant area index (PAI) and forest structure before and after cutting lianas (for 4 yr) in eight 80 m × 80 m plots and eight control plots (16 plots total). We used ground-based LiDAR to measure the 3-dimensional canopy structure before cutting lianas, and then annually for 2 yr afterwards. Six weeks after cutting lianas, mean plot PAI was 20% higher in control vs. liana removal plots. One yr after cutting lianas, mean plot PAI was ~17% higher in control plots. The differences between treatments diminished significantly 2 yr after liana cutting and, after 4 yr, trees had fully compensated for liana removal. Ground-based LiDAR revealed that lianas attenuated light in the upper- and middle-forest canopy layers, and not only in the upper canopy as was previously suspected. Thus, lianas compete with trees by intercepting light in the upper- and mid-canopy of this forest

Tropical Dry Forest Succession and the Contribution of Lianas to Wood Area Index (WAI)

The transmission and interception of light through the canopy is an important indicator of forest productivity in tropical forest ecosystems, and the amount of light that eventually reaches the forest floor is influenced by its interactions with leaves, branches, fruits, and flowers among many different canopy elements. While most studies of forest canopy light interception focus on leaf area index (LAI), very few studies have examined wood area index (WAI), which may account for a substantial component of light interception in tropical forests. The influence of lianas on the interception of light and their overall contribution to WAI is a potentially important factor, but it is generally overlooked because of its difficulty to assess. In this paper we evaluate the relative contribution that lianas have to the overall WAI and canopy openness as function of successional stage via a latitudinal comparison of sites across the Americas (Mexico, Costa Rica and Brazil). Our results suggest that lianas significantly increase WAI and decreases canopy openness. However, lianas were absent at all of our study sites where canopy openness exceeded 60%. Our data are the first to explicitly document the role of lianas in the estimation of WAI and, overall, they will contribute to better estimations of ecosystem level LAI in tropical environments, where there is a lack of data on WAI

Accuracy assessment on the number of flux terms needed to estimate in situ fAPAR

The fraction of Absorbed Photosynthetically Active Radiation (fAPAR) is a crucial variable for assessing global carbon balances and currently, there is an urgent need for reference data to validate satellite-derived fAPAR products. However, it is well-known that fAPAR ground measurements are associated with considerable uncertainties. Generally, fAPAR measurements can be carried out with two-, three- and four-flux approaches, depending on the number of flux terms measured. Currently, not much is known about the number of flux terms needed to satisfactorily reduce systematic errors. This study investigates the accuracy of different fAPAR estimates based on permanent, 10-min PAR measurements using Wireless Sensor Networks (WSNs) at three forest sites, located in Central Europe (mixed-coniferous forest), North America (boreal-deciduous forest) and Central America (tropical dry forest). All fAPAR estimates reflect the seasonal course of fAPAR. The highest average biases of different fAPAR estimates account to 0.02 at the temperate, 0.08 at the boreal and -0.05 at the tropical site, respectively, thereby generally fulfilling the uncertainty threshold of a maximum of 10 % or 0.05 fAPAR units set by the Global Climate Observing System (GCOS, 2016). During high wind speed conditions at the boreal site, the bias of the two-flux fAPAR estimate exceeded the 0.05-uncertainty threshold. Three-flux fAPAR estimates were not found to be advantageous, especially at the tropical site. Our findings are beneficial for the development of sampling protocols that are needed to validate global satellite-derived fAPAR products

Multi-Annual Evaluation of Time Series of Sentinel-1 Interferometric Coherence as a Tool for Crop Monitoring

Interferometric coherence from SAR data is a tool used in a variety of Earth observation applications. In the context of crop monitoring, vegetation indices are commonly used to describe crop dynamics. The most frequently used vegetation indices based on radar data are constructed using the backscattered intensity at different polarimetric channels. As coherence is sensitive to the changes in the scene caused by vegetation and its evolution, it may potentially be used as an alternative tool in this context. The objective of this work is to evaluate the potential of using Sentinel-1 interferometric coherence for this purpose. The study area is an agricultural region in Sevilla, Spain, mainly covered by 18 different crops. Time series of different backscatter-based radar vegetation indices and the coherence amplitude for both VV and VH channels from Sentinel-1 were compared to the NDVI derived from Sentinel-2 imagery for a 5-year period, from 2017 to 2021. The correlations between the series were studied both during and outside the growing season of the crops. Additionally, the use of the ratio of the two coherences measured at both polarimetric channels was explored. The results show that the coherence is generally well correlated with the NDVI across all seasons. The ratio between coherences at each channel is a potential alternative to the separate channels when the analysis is not restricted to the growing season of the crop, as its year-long temporal evolution more closely resembles that of the NDVI. Coherence and backscatter can be used as complementary sources of information, as backscatter-based indices describe the evolution of certain crops better than coherence.This research work was supported by the the European Space Agency under Project SEOM-S14SCI-Land (SInCohMap), and by the Spanish Ministry of Science and Innovation (State Agency of Research, AEI) and the European Funds for Regional Development (Project PID2020-117303GB-C22)

Quality of social housing in Metropolitan Lima

ABSTRACT This article studies the quality and the satisfaction variables of the current situation as the housing in Metropolitan Lima, the Peruvian city with the highest population number, the largest number of homes from self-construction and, the lack of land to build new houses. Two instruments were designed to measure each one of the variables, and research was required to have a quantitative, transversal, and non-experimental approach. This study verified the direct relationship that exists between the variables and had determined the current state of each one. Besides, they will rank the dimensions of satisfaction for housing quality

The Dynamics of Deforestation: Evidence From Costa Rica

In this paper we estimate deforestation patterns (across time and 436 districts within Costa Rica) with an econometric method explicitly derived from a dynamic microeconomic model. While the underlying model is similar to that used by Stavins and Jaffe 1990, we use different econometric tools which permit us to condition on previous optimal selection of land as well as a plot's currents forest/clearing status, and allow for dynamic adjustments of unobserved variables. As our coefficients are estimated from forest transitions, this yields a theoretical basis for deforestation regressions in which the estimated coefficients can be linked to theory. Our methodology is most naturally applied to plot data, but can be applied to aggregates including districts (as in this paper) or even to countries. The paper starts with a model of individual land use choices. It then discusses how these decisions will change over time in response to observable and unobservable economic factors. As usual the effects of unobservable factors lie behind error distributions, and allow us to derive a testable econometric model. Both the model and econometric analysis explicitly recognize that, because of unobservable adjustment costs and other endogenous but unobservable economy wide changes in the profitability of land clearing the observed level of forest at a given time is likely to differ from the equilibrium level predicted by complete adjustment to the vector of observable independent variables (i.e., factors that affect relative returns from production using cleared versus using forested land). Observed forest levels (for districts) move gradually toward long-run equilibrium as well as responding to shocks in the level of the equilibrium resulting from changes in the factors that drive relative returns. This dynamic adjustment process means current district deforestation rates are conditional on past deforestation. The results could be used not only to understand deforestation and agricultural extensification pattern, but also as the basis for creating carbon baseline projections. The Kyoto Protocol requires credible baseline estimates in order to allow the Clean Development Mechanism to provide credit for avoided deforestation without damaging the integrity of the global climate change effort

The Mexican Non-toxic Jatropha curcas L., Food Resource or Biofuel?

Jatropha curcas L. is a promising natural resource which has been promoted globally for biodiesel production by policy makers and researchers in tropical and subtropical countries. However, both J. curcas seeds and oil have been found to be toxic to humans and domestic animals when consumed. A non-toxic genotype of J. curcas has been reported from some rural communities in southern Mexico, and is suitable for human consumption. This non-toxic germplasm has been used in traditional Totonacan cuisine in Mexico. However, increasing demand for J. curcas to be used in biofuel production is exerting pressure on the non-toxic genotype. In this work we analyze the possible origins and dispersal of non-toxic Jatropha by the Totonaca culture; the traditional uses of J. curcas seeds as a food; its status with respect to the Mexican commercial forestry regulations; and the risks associated with the demands of biofuels on this Mexican germplasm