SOBRE O VALOR ECONÔMICO DO SISTEMA DE IDENTIFICAÇÃO ANIMAL DOS EUA (NAIS): NOTÍCIAS A RESPEITO DO MAU DA VACA LOUCA AFETAM O CONSUMO DE CARNES?

Esse artigo investiga os efeitos de notícias a respeito do mau da vaca louca ou BSE sobre o consumo das carnes bovina, suína e de aves nos EUA. Presume-se que o sistema nacional de identificação animal (NAIS) poderia em tese atenuar a percepção de risco dos consumidores sobre contrair o mau da vaca louca ao consumir carnes. Sistemas de equações de demanda são estimados incorporando-se, como proxy da percepção de risco do consumidor, três séries de índices de segurança do alimento separadamente construídos para as carnes bovina, suína e de aves considerando-se notícias veiculadas sobre BSE ou mau da vaca louca na imprensa escrita. Essas séries de índices são construídos somando-se o número de referências nos principais jornais norte americanos à problemas de food safety relacionados com cada uma das carnes. Utiliza-se o melhor modelo estimado, escolhido com base em testes de especificação, para se construir três cenários simulando-se respectivamente os casos em que o NAIS não está implementado, está implementado apenas para bovinos, e está implementado para suínos e bovinos. Utilizando-se as diferenças entre as receitas estimadas para cada cenário e para cada tipo de carne como uma medida do potencial ganho advindo da implementação do NAIS, conclui-se que o impacto do mau da vaca louca sobre o consumo de carnes nos EUA seria suficiente para cobrir os custos com a implementação do NAIS. Naturalmente, esse resultado fica condicionado a quanto dos ganhos com o NAIS seriam transmitidos aos pecuaristas que são aqueles que, em última instância, arcarão com os custos de implementação e manutenção do NAIS.----------------------------------------------This article investigates the willingness to pay for the National Animal Identification System (NAIS) in the US. We assume that with the NAIS in place, consumers’ concerns about Bovine Spongiform Encephalopathy (BSE) or mad cow disease will be reduced and by inference consumers will be willing to pay for the NAIS. To estimate this level of willingness to pay a generalized almost ideal demand system including beef, pork and poultry is estimated, including indexes of perception of BSE based on news coverage of BSE in the U.S. We found that while news indexes of BSE were not individually significant, that they were jointly significant in test of preferred models. Using the preferred model, we constructed three scenarios on the basis of hypothesized impacts of the NAIS on consumers' food safety concerns about meat. Our conclusion is that the impact of BSE on consumer demand for meat was in itself sufficient to cover previously estimated costs of implementing the NAIS. However, it does so at the expense of pork and poultry which lose consumption relative to beef if the NAIS reduces consumers concerns as assumed. Other disease and pathogen potential would be expected to further enhance its value.Sistema nacional de identificação animal, segurança do alimento, sistema de equações de demanda, setor de carnes, EUA, Animal Identification System, Food Safety, System of Demand Equations, Meat Industry, USA, Food Consumption/Nutrition/Food Safety, Livestock Production/Industries,

Economic Evidence of Willingness to Pay for the National Animal Identification System in the US

This article investigates the willingness to pay for the National Animal Identification System (NAIS) in the US. It is assumed that with the NAIS in place, consumers' risk perception about zoonosis, BSE or mad cow and residues in meat may be mitigated. Therefore, food safety indices for beef, pork and poultry summing the number of references to meat safety found in the top fifty English language news articles in circulation in the US have been constructed. These indices were incorporated in generalized almost ideal demand systems to estimate the effect of those food safety scares on the demand for meat in the US. It has been found that food safety impacts upon the final demand for meat in the US are small and do not show lagged effects. Using the preferred model, three scenarios have been constructed on the basis of hypothesized impacts of the NAIS on consumers' food safety concerns about meat. Finally, the differences in the predicted total revenue for beef, pork and poultry between scenarios are used as gross measures of the NAIS' economic value to the meat sector. The main conclusion is that if the defense of the NAIS is based on its effect on the demand side of the market for meats it is expected that the US Federal government will need to pay for a great part of the costs with the NAIS; otherwise the NAIS is likely to be economically unfeasible in the US.Animal Identification System, Food Safety, System of Demand Equations, Meat Industry, USA, Food Consumption/Nutrition/Food Safety, Livestock Production/Industries, C22, Q11, Q13, Q18,

Model tests on the control behaviour of a test air supply system in open or closed-loop operation

The Leibniz Universität Hannover is currently establishing a new mechanical engineering campus which includes a new research building "Dynamics of Energy Conversion" (DEW). This building provides a large compressor station for either steady or dynamic (transient) operation of turbomachinery and power plant test rigs (e.g. air turbine, axial compressor, combustion chamber, planar cascade, acoustic wind tunnel). The test air supply system is designed to enable investigations under high load gradients over wide operating ranges with Reynolds and Mach numbers controlled independently in order to fulfil aerodynamic similarity conditions between reality and model experiments. This is achieved by closed loop operation of the test air supply system which allows independent adjustment of pressure, temperature and volume flow rate as well as independence from environmental influences such as temperature or humidity. The compressor station utilizes as first stage two parallel Roots-type PD compressors and as second stage two parallel screw compressors. The test rigs operate at expansion ratios between 1 and 6. Test rig inlet pressures range from 1 bar(abs) to 8 bar(abs) with a maximum mass flow rate of 25 kg/s. At all conditions temperatures can be regulated between 60°C and 200°C. The test air supply system has a maximum electric power input of approximately 6 MW. As stringent demands on stability and reproducibility have to be met and automatic operation was requested, a scaled and simplified but fully functional model of the test air supply system was built, mainly to enable testing of control methods and devices prior to their final implementation on site. The functional model uses DN150 piping and consists of one Roots-type PD compressor as first stage and one screw compressors as second stage. Both compressors are driven by electric motors regulated by frequency converters. A turbine test rig is represented in the model by an adjustable throttle valve. Precise control of the mass flow rate is provided by a cascaded adjustable bypass around the test rig. The paper describes the test air supply system and the scaled model and presents experimental results on the achievable stability of pressure, temperature and mass flow rate at the test rig inlet in steady operation at several operating conditions of the model

cGMP-Phosphodiesterase Inhibition Enhances Photic Responses and Synchronization of the Biological Circadian Clock in Rodents

The master circadian clock in mammals is located in the hypothalamic suprachiasmatic nuclei (SCN) and is synchronized by several environmental stimuli, mainly the light-dark (LD) cycle. Light pulses in the late subjective night induce phase advances in locomotor circadian rhythms and the expression of clock genes (such as Per1-2). The mechanism responsible for light-induced phase advances involves the activation of guanylyl cyclase (GC), cGMP and its related protein kinase (PKG). Pharmacological manipulation of cGMP by phosphodiesterase (PDE) inhibition (e.g., sildenafil) increases low-intensity light-induced circadian responses, which could reflect the ability of the cGMP-dependent pathway to directly affect the photic sensitivity of the master circadian clock within the SCN. Indeed, sildenafil is also able to increase the phase-shifting effect of saturating (1200 lux) light pulses leading to phase advances of about 9 hours, as well as in C57 a mouse strain that shows reduced phase advances. In addition, sildenafil was effective in both male and female hamsters, as well as after oral administration. Other PDE inhibitors (such as vardenafil and tadalafil) also increased light-induced phase advances of locomotor activity rhythms and accelerated reentrainment after a phase advance in the LD cycle. Pharmacological inhibition of the main downstream target of cGMP, PKG, blocked light-induced expression of Per1. Our results indicate that the cGMP-dependent pathway can directly modulate the light-induced expression of clock-genes within the SCN and the magnitude of light-induced phase advances of overt rhythms, and provide promising tools to design treatments for human circadian disruptions

An expression module of WIPF1-coexpressed genes identifies patients with favorable prognosis in three tumor types

Wiskott–Aldrich syndrome (WAS) predisposes patients to leukemia and lymphoma. WAS is caused by mutations in the protein WASP which impair its interaction with the WIPF1 protein. Here, we aim to identify a module of WIPF1-coexpressed genes and to assess its use as a prognostic signature for colorectal cancer, glioma, and breast cancer patients. Two public colorectal cancer microarray data sets were used for discovery and validation of the WIPF1 co-expression module. Based on expression of the WIPF1 signature, we classified more than 400 additional tumors with microarray data from our own experiments or from publicly available data sets according to their WIPF1 signature expression. This allowed us to separate patient populations for colorectal cancers, breast cancers, and gliomas for which clinical characteristics like survival times and times to relapse were analyzed. Groups of colorectal cancer, breast cancer, and glioma patients with low expression of the WIPF1 co-expression module generally had a favorable prognosis. In addition, the majority of WIPF1 signature genes are individually correlated with disease outcome in different studies. Literature gene network analysis revealed that among WIPF1 co-expressed genes known direct transcriptional targets of c-myc, ESR1 and p53 are enriched. The mean expression profile of WIPF1 signature genes is correlated with the profile of a proliferation signature. The WIPF1 signature is the first microarray-based prognostic expression signature primarily developed for colorectal cancer that is instrumental in other tumor types: low expression of the WIPF1 module is associated with better prognosis

Increased Risk of Fragility Fractures among HIV Infected Compared to Uninfected Male Veterans

BACKGROUND: HIV infection has been associated with an increased risk of fragility fracture. We explored whether or not this increased risk persisted in HIV infected and uninfected men when controlling for traditional fragility fracture risk factors. METHODOLOGY/PRINCIPAL FINDINGS: Cox regression models were used to assess the association of HIV infection with the risk for incident hip, vertebral, or upper arm fracture in male Veterans enrolled in the Veterans Aging Cohort Study Virtual Cohort (VACS-VC). We calculated adjusted hazard ratios comparing HIV status and controlling for demographics and other established risk factors. The sample consisted of 119,318 men, 33% of whom were HIV infected (34% aged 50 years or older at baseline, and 55% black or Hispanic). Median body mass index (BMI) was lower in HIV infected compared with uninfected men (25 vs. 28 kg/m²; p<0.0001). Unadjusted risk for fracture was higher among HIV infected compared with uninfected men [HR: 1.32 (95% CI: 1.20, 1.47)]. After adjusting for demographics, comorbid disease, smoking and alcohol abuse, HIV infection remained associated with an increased fracture risk [HR: 1.24 (95% CI: 1.11, 1.39)]. However, adjusting for BMI attenuated this association [HR: 1.10 (95% CI: 0.97, 1.25)]. The only HIV-specific factor associated with fragility fracture was current protease inhibitor use [HR: 1.41 (95% CI: 1.16, 1.70)]. CONCLUSIONS/SIGNIFICANCE: HIV infection is associated with fragility fracture risk. This risk is attenuated by BMI