279 research outputs found

    Calcium carbonate accumulation in deep strata and calcrete in Quaternary alluvial formations of Morocco

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    Morphological studies on various scales of calcium carbonate accumulation which cements the Quaternary alluvial formations of the Sebou and the Moulouya (Morocco), show that there are two types of accumulation. The first, a thin layer always found near the surface, appears to be derived from the local redistribution of calcium carbonate under the influence of pedogenetical phenomena. The second, found in deeper strata, is a homogeneous thicker layer. It develops below the water table, after a long displacement of calcium carbonate in solution. These cemented layers affect the evolution of landscape

    Reducing Ammonia Losses By Adding FeCI3 During Composting Of Sewage Sludge

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    The release of ammonia nitrogen during composting of sewage sludge mixed with a lignocellulosic bulking agent leads to a reduction in the agronomic value of the final compost and to harmful effects on the environment. We propose adding a cheap salt FeCl3 which can be used without special precaution to reduce ammonia losses by decreasing pH conditions. An in-vessel co-composting experiment was conducted in a large reactor (100 L) in which FeCl3 was added to sludge mixed with a bulking agent (pine shavings and sawdust) and compared with a control mixture without FeCl3. Temperature, oxygen consumption and pH were monitored throughout the composting of both mixtures. The final balance of organic matter, organic and inorganic nitrogen permitted to conclude that the addition of FeCl3 reduced nitrogen loss (by a factor of 2.4 in relation to the control) and increased mineralisation of the organic nitrogen by 1.6

    Astrocytes in Pathogenesis of Multiple Sclerosis and Potential Translation into Clinic

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    Astrocytes are the most abundant glial cells in the central nervous system (CNS) and play a pivotal role in CNS homeostasis and functionality. Malfunction of astrocytes was implicated in multiple neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), Parkinson’s disease (PD), Alzheimer’s disease (AD), and multiple sclerosis (MS). The involvement of astrocytes in the pathology of neurodegenerative disorders supports the rationale of transplantation of healthy human astrocytes that can potentially compensate for diseased endogenous astrocytes. In this review, we will focus on the roles of astrocytes in the healthy CNS and under MS conditions. We will describe the cell sources and current cell-based therapies for MS with a focus on the potential of astrocyte transplantation. In addition, we will cover immerging early-stage clinical trials in MS that are currently being conducted using cell-based therapies

    Agronomic and environmental impacts of a single application of heat-dried sludge on an Alfisol

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    A field experiment was conducted on Alfisols in South-West France to assess the agronomic and environmental impacts of a single application of heat-dried sludge pellets at 11.1 Mg dry matter ha-1. The sludge pellets, with a moisture level of 9.5%, were spread on an irrigated crop of maize (Zea mays L.). This treatment was compared with inorganic fertilization (urea and diammonium phosphate mixed with KCl). Soil properties, yield and the composition of maize and the quality of drained water were monitored over 1 year to detect any changes resulting from sludge application. Amongst several determined soil properties, only two were significantly modified by the sludge application: The nitric nitrogen stock of the soil was higher in the inorganic fertilized plot, whereas Olsen-P soil content was higher in the sludge-amended plot. Agronomic recovery rates of N and P added by sludge were high: For the first crop following application, total amounts of N and P supplied by the sludge had the same efficiency as approximately 45% of the N and P amounts supplied by inorganic fertilizer. This ratio was 7% for the N uptake by the second maize crop. The quality and quantity of maize were equally good with both types of fertilization. During the 2 years following sludge spreading, N leaching remained as low in the sludged plot as in the inorganically fertilized one. The Cu, Zn, Cr, Cd, Pb and Ni composition of the drainage water was affected by neither of the types of amendment. From the heavy-metal contents of the soil, water and maize monitored over 1 year in the field experiment and from literature data for cow manure and atmospheric emissions, a theoretical balance between crop soil heavy-metal input and output over one century was drawn up. The long-term impact of cow manure on Zn, Ni and Cr in soil is higher than that of the studied heat-dried sludge. Obviously, sludge tended to cause a strong increase in soil Cu storage, valued for these soils, which are otherwise very Cu deficient

    7200 years of RhĂ´ne river flooding activity in Lake Le Bourget, France: a high-resolution sediment record of NW Alps hydrology.

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    Magnetic susceptibility (MS) was measured with high resolution (5 mm) on a 9 m long, 14C dated core from Lake Le Bourget (Savoie, France), spanning the last 7200 years. The strong correlation (R = 0.85) of the MS with the silicate-borne suite of elements (Si, Al, Fe,Mg, K) and anti-correlation with the carbonate content (R = -0.87) allows it to be used as a proxy for the fluctuations of the abundance of riverborne clastic fraction versus authigenic carbonates in sediment. As the RhĂ´ne is the only river bringing a significant amountof silicate minerals to the coring site, the MS downstream is interpreted as a proxy of the RhĂ´ne suspended load discharge in Lake Le Bourget. This is confirmed over the last 3000 years by the good match with the evolution of hydrological activity of the RhĂ´ne as it is known throughgeomorphological studies of well-dated archaeological sites. Over the last 7200 years, the record is consistent with the regional record of lake water-level fluctuations. While the intensity of the MS signal might be widely affected by the human impact on soil stability, the timing of theperiod of enhanced hydrological activity appears to be mostly climate-related, and should thus constitute a first step toward a high-resolution (<8 yr) continuous history of hydrological conditions in the NW Alps

    Astrocytes in Pathogenesis of ALS Disease and Potential Translation into Clinic

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    Astrocytes are the major cell population in the central nervous system (CNS) and play pivotal role in CNS homeostasis and functionality. Malfunction of astrocytes were implicated in multiple neurodegenerative diseases and disorders, including amyotrophic lateral sclerosis (ALS), spinal cord injury (SCI), brain stroke, Parkinson’s disease (PD), and Alzheimer disease (AD). These new insights led to the rationale that transplantation of healthy and functional human astrocytes could support survival of neurons and be of therapeutic value in treating neurodegenerative diseases. Here, we will mainly focus on the role of astrocytes in ALS disease, the major cell sources for generation of human astrocytes, or astrocyte like cells and show how multiple preclinical studies demonstrate the efficacy of these cells in animal models. In addition, we will cover immerging early stage clinical trials that are currently being conducted using human astrocytes or human astrocyte like cell population

    Preventing acute decrease in renal function induced by coronary angiography (PRECORD): a prospective randomized trial

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    SummaryBackgroundInfusion of saline attenuates the decrease in renal function induced by radiographic contrast agents among patients with chronic renal insufficiency.AimThe Preventing Renal alteration in Coronary Disease (PRECORD) trial was a randomized trial to assess the effect on renal function of saline infusion during and after coronary angiography in 201 patients without severe chronic renal insufficiency (serum creatinine<140μmol/L).MethodsAll patients received standard oral hydration: 2000mL of tap water within the 24hours after coronary angiography. Patients were randomized before the procedure to intravenous hydration (1000mL of 0.9% saline infusion) or no additional hydration. The infusion was started in the catheterization laboratory and continued for 24hours. The primary endpoint was the change in calculated creatinine clearance between baseline and 24hours after coronary angiography. The same ionic low osmolar radiographic contrast agent (ioxaglate) was used in all patients.ResultsBoth groups had similar baseline characteristics, including age, serum creatinine, volume of contrast and proportion of patients undergoing ad hoc coronary angioplasty. The overall decrease in serum creatinine clearance 24hours after the procedure was –3.44 (0.68)mL/min. The change in serum creatinine clearance 24hours after the procedure was –2.81 (1.07)mL/min in the infusion group vs –4.09 (0.91)mL/min in the control group (p=0.38).ConclusionRenal function is altered only slightly 24hours after coronary angiography with standard oral hydration alone and is not affected by saline infusion started at the beginning of coronary angiography, even in patients with mild-to-moderate renal dysfunction

    McMaster-Toronto Arthritis Patient Preference Disability Questionnaire Sensitivity to Change in Low Back Pain: Influence of Shifts in Priorities

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    To assess the sensitivity to change of the McMaster Toronto Arthritis Patient Preference Disability Questionnaire (MACTAR) in chronic low back pain (CLBP) and shifts in patients' priorities of disabling activities over time.A prospective longitudinal survey of 100 patients (38 males) with CLBP in a tertiary care teaching hospital. Evaluation at baseline and 6 months by the MACTAR, Quebec Back Pain Disability Questionnaire (QUEBEC), Hospital Anxiety and Depression scale (HAD), Fear-Avoidance Beliefs Questionnaire (FABQ), Coping Strategies Questionnaire (CSQ), and pain and handicap visual analogue scales (VASs). Patients' perceived improvement or worsening of condition was assessed at 6 months. Effect size (ES) and Standardized response mean (SRM) and effect size (ES) were used to evaluate sensitivity to change of the MACTAR.The MACTAR SRM and ES values (SRM = 0.25; ES = 0.37) were among the highest for the instruments evaluated. For patients considering their condition as improved, the SRM was 0.66 and the ES 1. The 3 disability domains, classified by the International Classification of Functioning, Disability and Health (ICF), most often cited as priorities at baseline remained the most cited at follow-up: mobility (40.9% of patients); community, social and civic life (22.7%); and domestic life (22.4%). At 6 months, 48 patients shifted their priorities, for a decrease in MACTAR SRM and ES values for patients considering their condition improved and an increase in these values for those considering their condition deteriorated.Although the MACTAR has similar sensitivity to change as other outcome measures widely used in CLBP, shifts in patient priorities over time are common and influence scores and sensitivity to change

    Structural characterization of fulvic acids, extracted from sewage sludge during composting, by thermochemolysis–gas chromatography–mass spectrometry

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    Thermochemolysis coupled with gas chromatography and mass spectrometry were applied to determine the chemical structure of fulvic acids (FA) extracted from a sewage sludge and straw mixture at different steps of composting. The FA starting structures were composed mainly of mono-, di- and tri-methoxy (alkyl) benzoic acids representing lignin derivatives in an advanced stage of oxidation, as well as of methylated polyphenols and a series of fatty acids saturated C15, C16, C18, unsaturated and branched C18:1. Besides, there are many unidentified structures suspected to be N-containing compounds. During the composting process, the fate of the three structural typical monomer units of lignin was followed. The p-hydroxyphenyl units showed a strong relative decrease especially at the beginning of composting. The guiaicyl units showed a steady increase in course of composting. A relative decrease of syringyl units was noted at the beginning of composting, but they then relatively increased towards the end of composting. These changes support the formation during composting of more oxidized units. All subunits composing the fulvic acid structures have been subdivided into main five groups of similar chemical structure. The lignin-like C6–C3 subunits showed a relative decrease during composting attributed to microbial oxidation, but there was a relative increase during the intermediate step of composting related probably of an enhancing of lignin solubility. The C6–C1 subunits were reduced at the beginning of composting, which mainly attributed to the oxidation of 4-methoxybenzaldehyde to hydroquinones derivatives under the composting conditions. Although, the relative increase of these subunits (C6–C1) at the end of composting originates from oxidation of C6–C3 lignin side-chains or could be partly attributed to microbial neosynthesis. The unidentified N-containing compounds increased strongly during course of composting. The rise in the level of fatty acids at the beginning of composting is attributed to an increase of branched-chain fatty acids such as C18:1 commonly used as bacterial biomarkers. Their amounts were greatly reduced at the end of composting. Both the Shannon–Weaver and similitude indices show a relative increase in structural diversity at the start of composting conditions following the appearance of hydroquinone derivatives and unidentified nitrogen compounds in the FA network. But, the produced FA structure reaches a certain level of homogeneity at the end of composting through self-polycondensation or recombination of C6–C1 subunits and hydroquinones derivatives with N-containing compounds

    Comparative study of humic acids of the mound of a wood-feeding termite and of the litter directly below in the Amazon river delta

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    In order to determine the role of termites in the recycling of organic matter and in humification processes, organic matter from the mound of a wood-feeding termite (Nasutitermes sp.) and from the litter directly below has been studied in secondary forest on the campus of Belem University, in Brazil. The carbon content was slightly lower in the litter ( just beneath the mound) than in the mound, but nitrogen was much more abundant in the mound. As a consequence, the C/N ratio of fragmented litter total organic matter is very high, which shows that the humification process is not complete. Therefore, plant debris seemed to be more degraded in the mound than in the litter, indicating a humification gradient from mound to litter. Humic acid extracted from the mound and from the litterwas compared by using elemental, E4/E6 ratio, spectroscopic (FTIR) analyses, and Sephadex gel chromatography. First, humic acids were more abundant in the mound than in the litter, showing that humification processes were more advanced in the mound than in the litter. Gel-permeation chromatography showed that the humic acids of the mound contained more low-molecular-weight fractions than those of the litter. In addition, the results of infrared spectra, E4/E6 ratio and elemental composition can confirm the fulvic character of mound material and the humic character of litter material. Therefore, the plant debris seems to follow two different humification pathways in the two environments, as long as the mound is alive
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