THE ROLE OF ENVIRONMENTAL EDUCATION IN PREDICTING ADOPTION OF WIND EROSION CONTROL PRACTICES

Logit and ordered probit analyses were used to identify factors associated with reduced tillage adoption, continuous spring cropping, and the number of changes made in response to wind erosion. Contrary to previous results for water erosion control, simple perception of a wind erosion problem or membership in a particular socioeconomic category did not significantly explain adoption of wind erosion control practices, but participating in a targeted educational program did. This educational program: (a) highlighted the threats of wind erosion to human health and to soil productivity, and (b) described specific potentially profitable farming practices for solving the wind erosion problem.Environmental Economics and Policy,

Advanced onboard storage concepts for natural gas-fueled automotive vehicles

The evaluation of several advanced concepts for storing natural gas at reduced pressure is presented. The advanced concepts include adsorption on high surface area carbon, adsorption in high porosity zeolite, storage in clathration compounds, and storage by dissolution in liquid solvents. High surface area carbons with high packing density are the best low pressure storage mediums. A simple mathematical model is used to compare adsorption storage on a state of the art carbon with compression storage. The model indicates that a vehicle using adsorption storage of natural gas at 3.6 MPa will have 36 percent of the range, on the EPA city cycle, of a vehicle operating on a compression storage system having the same physical size and a peak storage pressure of 21 MPa. Preliminary experiments and current literature suggest that the storage capacity of state of the art carbons could be improved by as much as 50 percent, and that adsorption systems having a capacity equal to compression storage at 14 MPa are possible without exceeding a maximum pressure of 3.6 MPa

Human papilloma virus genotype distribution and risk factor analysis amongst reproductive aged women in urban Gambia

Purpose. Cervical cancer is the most frequently diagnosed female cancer in The Gambia, representing approximately 30% of cases. In 2014, the quadrivalent human papilloma virus (HPV) vaccine was introduced, which offers protection against HPV genotypes 6, 11, 16 and 18. To evaluate the potential effectiveness of this vaccine, genotype distribution and risk factor analysis were assessed. Methodology. Endocervical samples (n=232) were collected from women aged 20-49 years residing in urban Gambia. A questionnaire was administered to capture socio-demographic and cervical cancer risk factors. HPV detection and genotyping was performed by PCR amplification of the L1 major capsid gene and analysis of sequenced PCR products. Results/ Key Findings. The prevalence of HPV was 12% (28/232) and the high risk (HR) genotype HPV 52 (5/28) was the most prevalent genotype. HR-HPV sequences had high identity (≥ 90 %) to isolates which originated from America, Europe and Asia but not from Africa. Half (14/28) of participants were co-infected with Ureaplasma urealyticum/parvum, which increases the risk of progression to cervical cancer. Female genital mutilation and the use of hormone contraception for >5 years were identified as potential risk factors for HPV infection. Ethnicity-associated differences were also noted; participants of the Fula ethnic group had a higher prevalence of HR-HPV infection (31.3%) compared to the Mandinka (18.8%) and Wollof (12.5%) groups. Conclusion. These data may have a significant public health impact as the HPV quadrivalent vaccine may be of limited value if the circulating non-HPV 16/18 HR-genotypes are responsible for cytological abnormalities of the cervix

Human papillomavirus Genotype Distribution and Co-infection with Sexually Transmitted Pathogens in Reproductive age Women in Urban Gambia

Cervical cancer is the second most common female cancer in The Gambia, and there have been few studies carried out on the causative agent, human papillomavirus (HPV) in this country. The Gambia introduced the quadrivalent HPV vaccine for girls between the ages of 9-13 years in the urban area in 2014; nationwide immunization will take place in 2019. This study determined the common circulating oncogenic HPV types in the urban region where most cervical cancer cases were reported. Two hundred and thirty-two women between 20 – 49 years of age from the urban region who attended a polyclinic were recruited for this work. Endocervical and high vaginal swabs were collected, and a socio-demographic questionnaire was administered to capture potential risk characteristics associated with HPV. Nucleic acid amplification techniques and DNA sequencing were carried out to determine the HPV genotype using PGMY09/11 consensus primers. Phylogenetic analysis was carried out on the Gambian HPV sequences to further confirm the identification of The Gambian HPV genotypes and its relatedness to sequences of the same types from other geographical locations. Microbiological and nucleic acid amplification analyses were used to determine the prevalence of other sexually transmitted pathogens in the participants. Blood samples, endocervical swab, and Pap smear were collected from HIV positive participants and these participants were followed up and re-examined every nine months for 24 months, to determine the persistence of cervical HPV infection, HPV antibodies, and cytological cervical changes. Pseudo-typed neutralisation assays were performed to characterise high-risk HPV antibodies in HIV positive women. Among the sample population studied, HPV prevalence was found to be 12% (28/232). HPV 52 was the most prevalent (17.9%) genotype detected in cervical samples. The Gambian high-risk HPV genotypes, except for a novel putative HPV 35 genotype, were 98 -100% identical to those submitted in the GenBank database. Prolonged (> 5 years) use of hormone contraceptive was the only variable found to associate statistically with HPV infection. Fifty percent (14/28) of participants infected with HPV were co-infected with Ureaplasma urealyticum/parvum and 25% (7/28) with HIV. HPV sero-prevalence was found to be 51.7% (15/29) in HIV positive participants. HIV positive women had been exposed to multiple HPV types and HPV 52 antibody was more prevalent 24% (7/29). Other high-risk HPV genotypes were found to cause high-grade cervical lesions and cancer in HIV positive women. Future studies to investigate oncogenic HPV genotypes in cervical cancer specimens will be useful in providing evidence for policies and future evaluation of the quadrivalent HPV vaccine in The Gambia

NON-DARCY FLOW EVALUATION OF UNCONSOLIDATED POROUS MEDIA IN A CLOSED LOOP PERMEAMETER

A new closed loop permeameter was implemented in this work to study the fluid flow through two different unconsolidated porous media. An apparent permeability, similar to that proposed by Barree and Conway, was described in this work in terms of the absolute permeability combined with a new fluid property description, the inertial contribution factor that accounts for the domain of viscous and inertial forces. Such approach discriminate those properties of the rock as intrinsic permeability from those related to the fluid as the inertial contribution factor. The apparent permeability equation of Barree and Conway was applied to different intervals of the experimental data in which it was possible to obtain the Forchheimer coefficients as well as the inertial contribution factors according to each interval. Two different types of unconsolidated porous media materials were utilized in the new Closed Loop Permeameter, sand (1-2 mm) and glass spheres (3.96 mm). The equation of Barree and Conway provided a great agreement fitting the experimental data in a wide non-Darcy Reynolds number range. It was observed an increase in the Forchheimer coefficient and decrease in the apparent permeability with the flow rate increase. The results indicate a correlation between the permeability and the inertial effects in the non-Darcy turbulent regions in which the porous media materials with low permeability values are probably more subjected to flow losses due to the inertial effects

Protection by Inhaled Hydrogen Therapy in a Rat Model of Acute Lung Injury can be Tracked \u3cem\u3ein vivo\u3c/em\u3e Using Molecular Imaging

Inhaled hydrogen gas (H2) provides protection in rat models of human acute lung injury (ALI). We previously reported that biomarker imaging can detect oxidative stress and endothelial cell death in vivo in a rat model of ALI. Our objective was to evaluate the ability of 99mTc-hexamethylpropyleneamineoxime (HMPAO) and 99mTc-duramycin to track the effectiveness of H2 therapy in vivo in the hyperoxia rat model of ALI. Rats were exposed to room air (normoxia), 98% O2 + 2% N2 (hyperoxia) or 98% O2 + 2% H2 (hyperoxia+H2) for up to 60 h. In vivo scintigraphy images were acquired following injection of 99mTc-HMPAO or 99mTc-duramycin. For hyperoxiarats, 99mTc-HMPAO and 99mTc-duramycin lung uptake increased in a time-dependent manner, reaching a maximum increase of 270% and 150% at 60 h, respectively. These increases were reduced to 120% and 70%, respectively, in hyperoxia+H2 rats. Hyperoxia exposure increased glutathione content in lung homogenate (36%) more than hyperoxia+H2 (21%), consistent with increases measured in 99mTc-HMPAO lung uptake. In 60-h hyperoxia rats, pleural effusion, which was undetectable in normoxia rats, averaged 9.3 gram/rat, and lung tissue 3-nitrotyrosine expression increased by 790%. Increases were reduced by 69% and 59%, respectively, in 60-h hyperoxia+H2 rats. This study detects and tracks the anti-oxidant and anti-apoptotic properties of H2 therapy in vivo after as early as 24 h of hyperoxia exposure. The results suggest the potential utility of these SPECT biomarkers for in vivo assessment of key cellular pathways in the pathogenesis of ALI and for monitoring responses to therapies

Dimensionnement de structures composites par une méthode FE2 simplifiée. Application au calcul de réservoirs composites

National audienceOn propose dans cette étude la modélisation des phénomènes physiques à l'origine et induits par celui de rupture de fibre au sein d'un composite unidirectionnel. Cette modélisation, faite à l'échelle microscopique, permet de construire une base de données qui va décrire cette échelle au sein d'un procédé multiéchelles FE2 simplifié. Ce procédé est ensuite utilisé pour réaliser le dimensionnement à l'éclatement d'un réservoir composite bobiné