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Hydroliquefaction of green wastes to produce fuels   总被引:1,自引:0,他引:1  
The direct liquefaction of a biomass composed of a mixture of wastes (straw, wood and grass) was studied using Nickel Raney as catalyst and tetralin as a solvent. Tetralin allows to solubilize green waste from 330 °C at relatively low hydrogen pressure, and avoids the recondensation of the intermediate products. The green waste deoxygenation results mainly from a decarboxylation reaction. The addition of Raney Ni in the feed, increases the gas yield due to methane formation, without diminishing the yield in solvolysis oil. The catalyst hydrogenolyses the small molecules present in the light fraction. Moreover, it improves the quality of the oil by increasing the hydrogen transfer between the solvent and the solvolysis oil. As a consequence, the oxygen content decreases and the yield of oil soluble in hexane strongly increases. The catalyst allows to obtain straight long chain alkanes (C13-C26), which result from the hydrogenation of the extractives compounds of the green waste.  相似文献   
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Background

Vitamin D is involved in brain physiology and lower-extremity function. We investigated spectroscopy in a cohort of older adults to explore the hypothesis that lower vitamin D status was associated with impaired neuronal function in caudal primary motor cortex (cPMC) measured by proton magnetic resonance spectroscopic imaging.

Methods

Twenty Caucasian community-dwellers (mean±standard deviation, 74.6±6.2 years; 35.0% female) from the ‘Gait and Brain Study’ were included in this analysis. Ratio of N-acetyl-aspartate to creatine (NAA/Cr), a marker of neuronal function, was calculated in cPMC. Participants were categorized according to mean NAA/Cr. Lower vitamin D status was defined as serum 25-hydroxyvitamin D (25OHD) concentration <75 nmol/L. Age, gender, number of comorbidities, vascular risk, cognition, gait performance, vitamin D supplements, undernourishment, cPMC thickness, white matter hyperintensities grade, serum parathyroid hormone concentration, and season of evaluation were used as potential confounders.

Results

Compared to participants with high NAA/Cr (n = 11), those with low NAA/Cr (i.e., reduced neuronal function) had lower serum 25OHD concentration (P = 0.044) and more frequently lower vitamin D status (P = 0.038). Lower vitamin D status was cross-sectionally associated with a decrease in NAA/Cr after adjustment for clinical characteristics (β = −0.41, P = 0.047), neuroimaging measures (β = −0.47, P = 0.032) and serum measures (β = −0.45, P = 0.046).

Conclusions

Lower vitamin D status was associated with reduced neuronal function in cPMC. These novel findings need to be replicated in larger and preferably longitudinal cohorts. They contribute to explain the pathophysiology of gait disorders in older adults with lower vitamin D status, and provide a scientific base for vitamin D replacement trials.  相似文献   
4.

Background

Breast cancer with oestrogen receptor expression is common in older women. Several factors, such as age and reproductive hormone exposure, have been associated with oestrogen receptor expression in breast cancer. However, the association between comorbidities and the oestrogen receptor expression has been poorly studied. We hypothesized that there was an association between burden comorbidity and breast cancer with oestrogen receptor expression in older women.

Objective

To determine whether oestrogen receptor expression in breast cancer was associated with burden comorbidity in community-dwelling women.

Methods

A total of 1,707 women with breast cancer registered on the list of a breast cancer registry were included. The recorded data included: age, Charlson Comorbidity Index score≥1, breast cancer characteristics (coded according to the International Classification of Diseases for Oncology), and breast cancer pathological stage (the pathological-tumour-node-metastasis, Scarff Bloom Richardson, and hormonal status of oestrogen receptor, progesterone receptor, and human epidermal growth factor receptor).

Results

Breast cancer with oestrogen receptor expression was identified in 1,378 patients (80·7%). The fully-adjusted logistic regression showed that oestrogen receptor expression was associated with Charlson Comorbidity Index score≥1 (odds ratio [OR] = 1·91,95%confidence interval [CI] = [1.01–3.61], P = 0·048), progesterone receptor expression (OR = 16·64, 95%CI = [11.62–23.81], P<0·001), human epidermal growth factor receptor (OR = 0·54, 95%CI = [0.34–0.84], P = 0·007), age (OR = 1.02, 95%CI = [1.00–1.03], P = 0.008), Scarff Bloom Richardson grade II and grade III (OR = 0·21with 95%CI = [0.10–0.44] and OR = 0·06 with 95%CI = [0.03–0.12], P<0·001).

Conclusion

Our findings provide new data showing an independent positive association between burden comorbidity and breast cancer with oestrogen receptor expression. This result confirms that evaluation of oestrogen receptor expression in breast cancer should not be limited to hormonal factors stratified by age.  相似文献   
5.
Purpose

Improving the environmental performances of viticulture practices is particularly complicated during unfavorable climatic conditions because of the need for fungal and other pest pressure and the variability of phytosanitary control methods available for winegrowers. However, winegrowers wish to improve the environmental performances of their practices regardless of climatic conditions. The objective of the study was to quantify the variability in environmental impacts due to climatic variations, and changes in viticulture practices induced by climatic variability.

Methods

Life cycle assessment was used to evaluate the environmental impacts of viticulture technical management routes (TMR) implemented on five plots in the Loire Valley for the Chenin Blanc grape variety. These TMRs are representative of the range of practices used in the region, including intensive conventional practices to moderate organic practices. The study covered two different years of production (2011 and 2013) under contrasting climatic conditions. The first year (2011) was hot and dry, which are favorable conditions for viticulture, while the second year (2013) was cold and humid, which are unfavorable conditions.

Results and discussion

During the unfavorable year, the number of phytosanitary treatments and soil maintenance interventions increased for most of the studied TMRs. This meant that the inter-annual variability in environmental impact was significant, depending on the type of TMR, with differences in impacts ranging from 19% to more than 40% between 2011 and 2013. Managing environmental impacts was found to be more difficult for the organic systems when climatic conditions are unfavorable (in 2013). The non-organic TMRs showed less variation in environmental impacts than the organic TMRs between the 2 years studied.

Conclusions

This study shows the importance of taking into account inter-annual variability in environmental assessments of viticulture systems. Indeed, winegrowers do not respond the same way to climate variability mainly with regard to plant protection and soil maintenance. Viticulture is very sensitive to inter-annual climate variations due to the parasitic pressure variability. The different production systems do not give to winegrowers the same possibilities for adapting practices to limit their impact on the environment.

  相似文献   
6.

Background

The aims of this study were 1) to confirm that combinations of brief geriatric assessment (BGA) items were significant risk factors for prolonged LHS among geriatric patients hospitalized in acute care medical units after their admission to the emergency department (ED); and 2) to determine whether these combinations of BGA items could be used as a prognostic tool of prolonged LHS.

Methods

Based on a prospective observational cohort design, 1254 inpatients (mean age ± standard deviation, 84.9±5.9 years; 59.3% female) recruited upon their admission to ED and discharged in acute care medical units of Angers University Hospital, France, were selected in this study. At baseline assessment, a BGA was performed and included the following 6 items: age ≥85years, male gender, polypharmacy (i.e., ≥5 drugs per day), use of home-help services, history of falls in previous 6 months and temporal disorientation (i.e., inability to give the month and/or year). The LHS in acute care medical units was prospectively calculated in number of days using the hospital registry.

Results

Area under receiver operating characteristic (ROC) curves of prolonged LHS of different combinations of BGA items ranged from 0.50 to 0.57. Cox regression models revealed that combinations defining a high risk of prolonged LHS, identified from ROC curves, were significant risk factors for prolonged LHS (hazard ratio >1.16 with P>0.010). Kaplan-Meier distributions of discharge showed that inpatients classified in high-risk group of prolonged LHS were discharged later than those in low-risk group (P<0.003). Prognostic value for prolonged LHS of all combinations was poor with sensitivity under 77%, a high variation of specificity (from 26.6 to 97.4) and a low likelihood ratio of positive test under 5.6.

Conclusion

Combinations of 6-item BGA tool were significant risk factors for prolonged LHS but their prognostic value was poor in the studied sample of older inpatients.  相似文献   
7.

Background

Surveys measuring effectiveness of public awareness campaigns in reducing cardiovascular disease (CVD) incidence have yielded equivocal findings. The aim of this study was to describe cardiovascular risk factors (CVRFs) changes over the years in an untreated population-based study.

Methods

Between 2007 and 2012, we conducted a screening campaign for CVRFs in men aged 40 to 65 yrs and women aged 50 to 70 yrs in the western suburbs of Paris. Data were complete for 20,324 participants of which 14,709 were untreated.

Results

The prevalence trend over six years was statistically significant for hypertension in men from 25.9% in 2007 to 21.1% in 2012 (p=0.002) and from 23% in 2007 to 12.7% in 2012 in women (p<0.0001). The prevalence trend of tobacco smoking decreased from 38.6% to 27.7% in men (p=0.0001) and from 22.6% to 16.8% in women (p=0.113). The Framingham 10-year risk for CVD decreased from 13.3 ± 8.2 % in 2007 to 11.7 ± 9.0 % in 2012 in men and from 8.0 ± 4.1 % to 5.9 ± 3.4 % in women. The 10-year risk of fatal CVD based on the European Systematic COronary Risk Evaluation (SCORE) decreased in men and in women (p <0.0001).

Conclusions

Over a 6-year period, several CVRFs have decreased in our screening campaign, leading to decrease in the 10-year risk for CVD and the 10-year risk of fatal CVD. Cardiologists should recognize the importance of community prevention programs and communication policies, particularly tobacco control and healthier diets to decrease the CVRFs in the general population.  相似文献   
8.
BackgroundRespective and combined effects of impairments in sensorimotor systems and cognition on gait performance have not been fully studied. This study aims to describe the respective effects of impairments in muscle strength, distance vision, lower-limb proprioception and cognition on the Timed Up & Go (TUG) scores (i.e., performed TUG [pTUG], imagined TUG [iTUG] and the time difference between these two tests [delta TUG]) in older community-dwellers; and to examine their combined effects on TUG scores.MethodsBased on a cross-sectional design, 1792 community-dwellers (70.2±4.8 years; 53.6% female) were recruited. Gait performance was assessed using pTUG, iTUG and delta TUG. Participants were divided into healthy individuals and 15 subgroups of individuals according to the presence of impairment in one or more subsystems involved in gait control (i.e., muscle strength and/or distance vision and/or lower-limb proprioception and/or cognition [episodic memory and executive performance]). Impairment in muscle strength, distance vision and lower-limb proprioception was defined as being in the lowest tertile of performance. Impairment in cognition was defined as abnormal episodic memory and executive tests.ResultsA total of 191 (10.7%) exhibited impairment in muscle strength, 188 (10.5%) in distance vision, 302 (16.9%) in lower-limb proprioception, and 42 (2.3%) in cognition. Linear regressions showed that cognitive impairment as well as dual combinations of impairments were associated with increased pTUG (P<0.02). Impairment in lower-limb proprioception was associated with decreased iTUG (P=0.015). All combinations of impairments, except those including muscle strength and the combinations of the 4 subsystems, were associated with increased delta TUG (P<0.04).ConclusionCognitive integrity is central for efficient gait control and stability, whereas lower-limb proprioception seems to be central for gait imagery.  相似文献   
9.

Background

Vitamin D deficiency is associated with smaller volume of optic chiasm in older adults, indicating a possible loss of the visual axons and their cellular bodies. Our objective was to determine whether vitamin D deficiency in older adults is associated with reduced thickness of the ganglion cell complex(GCC) and of the retinal nerve fibre layer(RNFL), as measured with high-definition optical coherence tomography(HD-OCT).

Methods

Eighty-five French older community-dwellers without open-angle glaucoma and patent age-related macular degeneration(mean, 71.1±4.7years; 45.9%female) from the GAIT study were separated into 2 groups according to serum 25OHD level(i.e., deficient≤25nmol/L or sufficient>25nmol/L). Measurements of GCC and RNFL thickness were performed using HD-OCT. Age, gender, body mass index, number of comorbidities, dementia, functional autonomy, intracranial volume, visual acuity, serum calcium concentration and season of testing were considered as potential confounders.

Results

Mean serum 25OHD concentration was 58.4±26.8nmol/L. Mean logMAR visual acuity was 0.03±0.06. Mean visual field mean deviation was -1.25±2.29dB. Patients with vitamin D deficiency(n=11) had a reduced mean GCC thickness compared to those without vitamin D deficiency(72.1±7.4μm versus 77.5±7.5μm, P=0.028). There was no difference of the mean RNFL thickness in these two groups(P=0.133). After adjustment for potential confounders, vitamin D deficiency was associated with reduced GCC thickness(ß=-5.12, P=0.048) but not RNFL thickness(ß=-9.98, P=0.061). Specifically, vitamin D deficiency correlated with the superior medial GCC area(P=0.017) and superior temporal GCC area(P=0.010).

Conclusions

Vitamin D deficiency in older patients is associated with reduced mean GCC thickness, which can represent an early stage of optic nerve damage, prior to RNFL loss.  相似文献   
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