SOCIAL WELFARE AND ENVIRONMENTAL DEGRADATION IN AGRICULTURE: THE CASE OF ECUADOR

A non-linear optimization model which maximizes total Ecuadorian social welfare, defined as the sum of consumers' and producers' surpluses for the four major crops (corn, bananas, rice and African palm) is developed to evaluate the tradeoff between welfare and environmental degradation in Ecuador. It was found that a total welfare loss of US$122 million (a 11 percent reduction - from US$ 1.112 billion to US$ 989.66 million) would be expected from a 30 percent reduction in the total pesticide load on the environment in the production of the four major crops. The distributional impacts of the welfare loss were found, however, to be significantly skewed toward the loss of consumers' surplus. Specifically, a 30 percent reduction of total pesticide load on the environment would result in a reduction of 3.86 percent of producers' total surplus while consumers would be expected to loose 19.46 percent of their total surplus.welfare tradeoff, environmental impacts, non-linear optimization, Environmental Economics and Policy,

Improving Communication between Doctors and Parents after Newborn Screening

Background: Newborn screening (NBS) enables early treatment, and some consider it a natural vehicle for genetic screening. Bioethicists argue for caution since families of infants with carrier status can develop psychosocial complications. This paper describes the methods and feasibility of Wisconsin’s statewide project for quality improvement of communication and psychosocial outcomes after NBS. Methods: When NBS identifies carrier status for cystic fibrosis or sickle cell, we contact primary care providers (PCPs), answer questions, and invite them to rehearse informing the parents. Three months later, we telephone the parents, assess knowledge and psychosocial outcomes, provide counseling, and assist with self-referral to further resources. Afterward, evaluation surveys are provided to the parents, to be returned anonymously. Results: Birthing facilities provided accurate PCP names for 73% of 817 infants meeting inclusion criteria; we identified PCPs for 21% more. We reached 47.3% of PCPs in time to invite a rehearsal; 60% of these accepted. We successfully called 50.2% of eligible parents; 61% recalled a PCP explanation, and 48.5% evaluated the explanation favorably. Evaluations by parents with limited health literacy were less favorable. Conclusion: It is feasible to follow parents for psychosocial outcomes after NBS. Preliminary data about communication is mixed, but further data will describe psychosocial outcomes and investigate outcomes’ associations with communication

The Status Of Nuisance Wildlife Damage Control In The States

State fish and wildlife agencies and nuisance wildlife control operators must work together whether or not they actively choose to. In this paper, their relationship is likened to a marriage between two (not so likely) partners. In an attempt to assess the status of this relationship the International Association of Fish and Wildlife Agencies, The Wildlife Society\u27s Wildlife Damage Management Working Group, and the National Animal Damage Control Association developed a survey that addressed the level of state agencies\u27 oversight of nuisance wildlife control operators (NWCOs). Responses were received from 47 states, 1 territory, and 17 ADC state offices. This report concentrates on the responses from the U.S. states and territories. Currently 77% of states perform nuisance wildlife control activities. Private agents may euthanize nuisance animals for property owners in 95% of the states, and are allowed to relocate nuisance wildlife in 91 % of the states. Most states do not require NWCO\u27s to carry general liability insurance. Some states do not have a well-defined method for monitoring compliance with laws and regulations dealing with nuisance wildlife control activities. There appears to be a great deal of gray area in the relationship between NWCOs and the state agencies. National guidelines for the nuisance wildlife control industry may help clarify the responsibilities of the states and NWCOs with respect to each other and the private landowner

Limitations of Absolute Current Densities Derived from the Semel & Skumanich Method

Semel and Skumanich proposed a method to obtain the absolute electric current density, |Jz|, without disambiguation of 180 degree in the transverse field directions. The advantage of the method is that the uncertainty in the determination of the ambiguity in the magnetic azimuth is removed. Here, we investigate the limits of the calculation when applied to a numerical MHD model. We found that the combination of changes in the magnetic azimuth with vanishing horizontal field component leads to errors, where electric current densities are often strong. Where errors occur, the calculation gives |Jz| too small by factors typically 1.2 ~ 2.0.Comment: 10 pages, 4 figures. To appear on Science in China Series G: Physics, Mechanics & Astronomy, October 200

Detecting and defeating advanced man-in-the-middle attacks against TLS

Sobre los derechos de acceso: Permission to make digital or hard copies of this publication for internal use within NATO and for personal or educational use when for non-profi t or non-commercial purposes is granted providing that copies bear this notice and a full citation on the first page. Any other reproduction or transmission requires prior written permission by NATO CCD COE.TLS es un bloque esencial para la construcción de redes privadas. Un aspecto crítico para la seguridad de TLS es la autenticación y el intercambio de claves, que habitualmente se realiza mediante certificados. Un intercambio inseguro de claves puede conducir a un ataque de hombre en el medio (MITM). La confianza en los certificados se consigue habitualmente gracias a la utilización de una infraestructura de clave pública (PKI), que emplea autoridades de certificación (CA) de confianza para el establecimiento de cadenas de validez de certificados. En los últimos años, han surgido una serie de problemas relacionados con el uso del PKI: lo certificados pueden ser emitidos para cualquier entidad de Internet, con independencia de la posición de la CA en el árbol jerárquico. Esto implica que un ataque exitoso contra una CA tiene el potencial de permitir la generación de certificados válidos que posibilitarán la realización de ataques de hombre en el medio. No podemos descartar la posibilidad de usos malicioso de CA intermedias para llevar a cabo ataques dirigidos mediante la emisión de certificados ad-hoc, que serían extremadamente difíciles de detectar. La infraestructura PKI actual es susceptible a este tipo de ataques, por lo que se hace necesaria la creación de nuevos mecanismos para la detección y neutralización de los mismos. El IETF y otros organismos de estandarización han lanzado distintas iniciativas para posibilitar la detección de certificados falsificados. La mayoría de estas iniciativas intentan solucionar los problemas existentes mantenimiento el modelo PKI y agregando la técnica de 'certificate pinning', que asocia certificados concretos a servidores. Estas técnicas tienen limitaciones significativas, como la necesidad de un proceso de arranque seguro, o el establecimiento de la asociación para cada host de forma individual y uno por uno. Este trabajo proporciona una evolución desde el esquema de 'pinning' realizado en el host a un esquema de 'pinning' en la red, mediante la habilitación de mecanismos para la validación de certificados cuando atraviesan una red determinada. Los certificados se clasificarán como confiables o no como resultado del cruce de información obtenida de distintas fuentes. Esto resultaría en la detección temprana de certificados sospechosos y lanzaría mecanismos para rechazar el ataque, minimizar su impacto y recopilar información sobre los atacantes. Junto con lo anterior, se podría realizar un análisis más detallado y pormenorizado.TLS is an essential building block for virtual private networks. A critical aspect for the security of TLS dialogs is authentication and key exchange, usually performed by means of certificates. An insecure key exchange can lead to a man-in-the-middle attack (MITM). Trust in certificates is generally achieved using Public Key Infrastructures (PKIs), which employ trusted certificate authorities (CAs) to establish certificate validity chains. In the last years, a number of security concerns regarding PKI usage have arisen: certificates can be issued for entities in the Internet, regardless of its position in the CA hierarchy tree. This means that successful attacks on CAs have the potential to generate valid certificates enabling man-in-the-middle attacks. The possibility of malicious use of intermediate CAs to perform targeted attacks through ad-hoc certificates cannot be neglected and are extremely difficult to detect. Current PKI infrastructure for TLS is prone to MITM attacks, and new mechanisms for detection and avoidance of those attacks are needed. IETF and other standardization bodies have launched several initiatives to enable the detection of “forged” certificates. Most of these initiatives attempt to solve the existing problems by maintaining the current PKI model and using certificate pinning, which associates certificates and servers on use. These techniques have significant limitations, such as the need of a secure bootstrap procedure, or pinning requiring some host-by-host basis. This study proposes an evolution from pinning-in-the-host to pinning-in-the-net, by enabling mechanisms to validate certificates as they travel through a given network. Certificates would be classified as trusted or not trusted as a result of cross-information obtained from different sources. This would result in early detection of suspicious certificates and would trigger mechanisms to defeat the attack; minimize its impact; and gather information on the attackers. Additionally, a more detailed and thorough analysis could be performed

La contribución de los videojuegos online de modalidad competitiva en la vida personal de los adolescentes

La presente investigación tiene como objetivo analizar cuáles son las contribuciones de los videojuegos online de modalidad competitiva en la vida personal de los adolescentes de Lima Metropolitana. La metodología a emplearse para esta investigación tiene un enfoque cualitativo descriptivo, para ello se utilizará la herramienta de las entrevistas para recopilar la información. Para las entrevistas, se ha dividido las preguntas en tres categorías. El motivo de esta investigación recae en el contexto de la situación mundial: la pandemia por el Covid- La interacción de los adolescentes con los videojuegos se ha reforzado vertiginosamente debido a la estancia excesiva en el hogar. Además, se sabe que los videojuegos implican efectos positivos y negativos a las personas que practican alguno de estos videojuegos, y en este caso, en particular, se va a referir a los aspectos positivos que fomentan los videojuegos.The present research aims to analyze what are the contributions of competitive online video games in the personal lives of adolescents in Metropolitan Lima. The methodology to be used for this research has a descriptive qualitative approach, for which the interview tool will be used to collect the information. For the interviews, the questions have been divided into three categories. The reason for this investigation lies in the context of the world situation: the Covid-19 pandemic. The interaction of adolescents with video games has been reinforced dramatically due to excessive stay at home. In addition, it is known that video games imply positive and negative effects on people who play any of these video games, and in this case, in particular, it is going to refer to the positive aspects that video games promote.Trabajo de investigació

A microarray analysis of gene expression in the free-living stages of the parasitic nematode Strongyloides ratti

BACKGROUND: The nematode Strongyloides ratti has two adult phases in its lifecycle: one obligate, female and parasitic and one facultative, dioecious and free-living. The molecular control of the development of this free-living generation remains to be elucidated. RESULTS: We have constructed an S. ratti cDNA microarray and used it to interrogate changes in gene expression during the free-living phase of the S. ratti life-cycle. We have found very extensive differences in gene expression between first-stage larvae (L1) passed in faeces and infective L3s preparing to infect hosts. In L1 stages there was comparatively greater expression of genes involved in growth. We have also compared gene expression in L2 stages destined to develop directly into infective L3s with those destined to develop indirectly into free-living adults. This revealed relatively small differences in gene expression. We find little evidence for the conservation of transcription profiles between S. ratti and S. stercoralis or C. elegans. CONCLUSION: This is the first multi-gene study of gene expression in S. ratti. This has shown that robust data can be generated, with consistent measures of expression within computationally determined clusters and contigs. We find inconsistencies between EST representation data and microarray hybridization data in the identification of genes with stage-specific expression and highly expressed genes. Many of the genes whose expression is significantly different between L1 and iL3s stages are unknown beyond alignments to predicted genes. This highlights the forthcoming challenge in actually determining the role of these genes in the life of S. ratti