Enlèvement du chrome par infiltration verticale sur lits de Phragmites australis (Cav.) Steudel

L'objectif de la présente étude est de mettre en évidence les potentialités d'un hélophyte : Phragmites australis (Cav.) Steudel à épurer l'effluent du tannage riche en chrome sous un régime d'écoulement vertical et les comparer à celles d'un sol non planté sous climat aride.Le pilote expérimental est constitué de pots de capacité 120 litres, remplis sur une épaisseur de 15 cm de graviers et de 60 cm de sol (texture : limono - argilo- sableuse). Trois pots sont plantés de jeunes tiges de Phragmites australis (36 tiges /m2). Trois autres pots non plantés sont pris comme témoin. L'alimentation du système se fait par l'eau du tannage au chrome diluée à 50%. L’alimentation des systèmes se fait par bâchées de 10 litres/jour pendant 3 jours successifs suivie d’une période de repos de 4 jours. L'écoulement se fait par translation verticale à travers le substrat.L'étude du fonctionnement hydrologique des pilotes testés a montré que le débit moyen à la sortie du système planté est trois fois plus élevé que celui du lit non planté, ce qui permet de traiter un volume d’eau usée plus important ou bien de réduire la superficie nécessaire par équivalent habitant. Aucun signe de colmatage n’a été détecté aussi bien dans les pots plantés de Phragmites australis que dans les pots non plantés.Le suivi des performances épuratoires du système à Phragmites australis montre que le pH à la sortie des deux systèmes pilotes augmente de deux à trois unités par rapport à celui des rejets du tannage. La conductivité électrique des effluents traités augmente respectivement pour les deux systèmes.L’élimination moyenne de la DCO totale est de 74% pour le système planté et de 60,5% pour le système non planté. La différence entre les performances épuratoires des deux systèmes pour l’abattement de la DCO totale est statistiquement significative (p<0,05).Le Cr total subit globalement un abattement de 99% pour les deux pilotes qui fournissent des eaux épurées limpides. En effet, la concentration moyenne en chrome total dans les eaux usées brutes appliquées à l'entrée des différents pilotes varie de 534 mg/l à 1000 mg/l avec une concentration moyenne de 780±196 mg/l. Les teneurs de chrome total enregistrées à la sortie du lit à Phragmites varient de 2,2 mg/l à 3 mg/l avec une concentration moyenne de 2±0,5 mg/l. La concentration en chrome total des eaux usées à la sortie du sol non planté varie de 2,5 mg/l à 4 mg/l avec une valeur moyenne de 2,4±1,3 mg/l.La présence de Phragmites australis dans le système planté permet de maintenir une porosité suffisante pour assurer la percolation des eaux en traitement et réduire les risques de colmatage. Avec des temps de résidence hydraulique trois fois plus réduit, le système planté assure un abattement du chrome total comparable à celui du système non planté.The aim of this study was to investigate the potential of a helophytic plant, Phragmites australis (Cav.) Steudel, to remove chromium from concentrated tannery effluent in comparison to unplanted soil, under arid climate conditions. The experiment was conducted from August 2002 to August 2003. Six plots (capacity: 120 L, diameter: 50 cm) were filled to depths of 15 cm and 60 cm with gravel and soil respectively (texture: 3.5% clay, 8.5% silt, and 88% sand). Three plots were planted with Phragmites australis (Cav.) Steudel. Young shoots of plants (36 stems/m2) were taken from local and natural reed stands. Three unplanted plots were used as controls. The soil for the study was from the Tensift River (Marrakech). The experimental plots were supplied exclusively with diluted tannery wastewater, 3 times a week (approximately 10 L each time). The water flowed vertically through the substratum.To investigate the capacity of the systems to increase pH, to decrease conductivity chemical oxygen demand (COD), and to remove total chromium, concentrations in the inflow and outflow of each plot were determined during the experiment. System hydrology indicated that for planted systems, the mean flow varied from 18 mL/min (in winter) to 49 mL/min (in summer), with an average value of 35 mL/min. For the unplanted system, the mean flow varied from 5 mL/min (in winter) to 15 mL/min (in summer) with an average value of 12 mL/min. Water recovery at the outflow of the planted system (PP) and unplanted system (NPP) was 40% and 60% respectively. This may be related to the phenomenon of evapotranspiration from the PP system, which was more significant than simple evaporation from the NPP system. No sign of clogging was observed in the planted systems due to the plant rhizomes that ensure a better aeration of the soil. The study of the hydrological operation showed that mean flow in the planted system was three times higher than that in the unplanted soil, which makes it possible to treat a larger volume of wastewater and to reduce the required per capita surface for treatment. The presence of Phragmites australis ensured a sufficient porosity for the percolation of water for treatment.The pH of the effluent at the outlets of the planted and unplanted systems increased by two to three units in comparison with the raw wastewater at the inlet. The average inflow pH was 5.5; at the outflow of the two systems, the pH was 7.30 and 8.20 respectively for the planted and unplanted soil. The electrical conductivity (EC) of the treated wastewater increased for the two systems. The average inflow conductivity was 54±5.5ms/cm. At the outflow of the two systems, the EC was about 75±14 ms/cm and 68±11 ms/cm respectively for the planted and unplanted systems. The EC removal for all systems varied significantly from season to another (p< 0.05).The planted system was more efficient in removing total COD (74%) than the unplanted one (61%). There were significant differences (ANOVA) between the PP and NPP systems (p<0.05). Total chromium concentrations at the inflow varied from 534 mg/L to 1000 mg/L with an average content of 780±196 mg/L. At the outflow, total chromium concentrations varied from 2.2 mg/L to 3 mg/L with an average content of 2±0.5 mg/L for the PP system and from 2.5 mg/L to 4 mg/L with an average value of 2.4±1.3 mg/L for the NPP system. Total chromium removal of 99% occurred for the two pilots, which provides limpid purified water. Despite the shorter retention time for the planted system, which was three times less than in the unplanted one, total chromium was almost completely removed.The aquatic macrophyte plant seemed to play a physical role by enhancing the hydrological conductivity of the substratum and consequently the operation and management of these systems. Phragmites australis (Cav.) Steudel has the ability to transfer oxygen from the rhizome towards the roots through an internal lacunar system, which offers the creation of an aerobic zone around the roots. This aerobic zone allows the proliferation of micro-organisms, which are the principal decomposers of the organic matter in the root zone.The treatment of tannery effluent by reed beds is a clean approach from an ecological point of view and constitutes a viable economic alternative in comparison to purely chemical approaches and is thus better adapted to the complexity of the systems used in the leather industry

Dried Distillers Grains Supplementation of Calves Grazing Irrigated Corn Residue

Steer calves grazing irrigated corn residue received supplementation of dried distillers grains plus solubles (DGS) at 0.3, 0.5, 0.7, 0.9, or 1.1% of body weight. Steers were individually supplemented daily through Calan gates. Daily gain improved linearly (0.77 lb/head/day to 2.21 lb/head/day) with increasing supplementation (1.5 lb/day to 7 lb/day). Supplementing DGS to calves grazing corn residue increased gain during the winter period

Outcome Measures for Interventions to Reduce Inappropriate Chronic Drugs: A Narrative Review

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/163374/3/jgs16697-sup-0001-Supinfo.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163374/2/jgs16697_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163374/1/jgs16697.pd

Evaluation of Changes in Nutritional Quality of Corn Residue Over Time

Irrigated corn residue was sampled across time in order to determine changes in quality and proportion of corn residue as the plant dried and was exposed to effects of weathering. Corn plants from two hybrids were planted on two different planting dates and harvested at periodic intervals from August 2012 to December 2012. Proportions of stem, blade/sheath, husk/shank, and cob made up smaller components of total plant DM as it matured, with the largest relative reduction occurring in the blade/sheath or stem. Hybrid impacted TDN values primarily because the 119 day hybrid was less mature at the early sampling dates

Comparison of Commercial Lick Tubs to Distillers Grains Supplementation for Calves Grazing Corn Residue

Steer calves grazing irrigated corn residue were supplemented dried distillers grains plus solubles (DGS) or allowedcontinuous access to a commercial lick tub. Dried DGS was fed at 2.94 lb/steer/day and the lick tubs were consumed at 2.04 lb/steer/day (DM basis). Gain was greater for cattle supplemented with dried DGS (1.36 lb/day) compared to those with access to lick tubs (0.83 lb/day). Supplement efficiency varied between calves receiving dried DGS (46%) and those with continuous access to the lick tub (43%) when expressed on a DM basis. Values for dried DGS supplementation (48%) were not different for supplement efficiencyon an OM basis when compared to cattle on the lick tub treatment (50%). Economic analysis shows that as the price of DGS increases, the difference in profit between supplementation strategiesis reduced

The Safe Use of Pesticides: A Risk Assessment Procedure for the Enhancement of Occupational Health and Safety (OHS) Management

The attention paid to the use of pesticides has increased notably in recent years as demonstrated by the issue of laws and regulations requiring their safe and environmentally-conscious use (e.g. Directive 2009/128/EC and Regulation (EC) no. 1272/2008). Despite the benefits that can be achieved by pursuing the targets of stricter legislative framework, the difficulties for farmers in complying with it are remarkable, especially for small-sized companies. In fact, in contrast to other occupational health and safety (OHS) contexts, in the case of pesticides even a preliminary analysis on the relationship between pesticide use and the consequent exposure risks for the workers is a complex task. In order to reduce the above-mentioned gap, the present study is focused on the development of an easy-to-use tool for carrying out occupational risk assessment of agricultural activities related to the use of pesticides. The procedure was developed by starting from the Agricultural Health Study (AHS) approach and its improvements, and continuing to the thorough development of a tool for preliminary risk assessment, providing a simplified model for its practical application by farmers. A case study concerning olive cultivation was used for its first verification. The results achieved should be considered as an initial step for the promotion of safer practices when using pesticides, providing a consistent base for their further validation

Splenectomy through the laparoscopic approach and how I do it

Scopul lucrării. Studierea cazurilor de splenectomie prin abord laparoscopic și clasic în vederea stabilirii cauzalității tip procedurăincidente perioperatorii și demonstrării superiorității abordului laparoscopic. Materiale și metode. Au fost selectate cazurile de splenectomie efectuate prin abord clasic și laparoscopic în Clinica de Chirurgie Colțea, perioada 01.01.2019-31.12.2022. Am revăzut filmările intraoperatorii, am evaluat factorii generali și locali asociați abordului chirurgical preferat. Rezultate. Au fost selectate 29 de cazuri, vârsta medie 54.8 ani, 72.4% femei, 27.6% barbati, 55.2% (16) cu multiple comorbidități: antecedente chirurgicale majore, insuficiența cardiacă, asmul bronșic sever etc. Cazurile au fost împărțite în 2 grupe: Gr. I- cu abord laparoscopic 34.5% (10), Gr. II- cu abord clasic 65.5% (19). Incidența comorbidităților a fost de 10% (1) în Gr.I, cu dimensiunea medie a splinei de 13.2 cm (min 8.5 cm, max 21 cm) și 84.2 % (16) în Gr.II cu dimensiunea medie a splinei de 20.4 cm (min 10 cm, max 34 cm). Doar în Gr.II au fost înregistrate sângerări intraoperatorii în 78.9% (15), iar in 15.8% (3) au fost complicații postoperatorii. Pacienții din Gr.I au avut o perioadă de spitalizare postoperatorie medie de 4 zile, iar cei din Gr. II de 7 zile și au fost externați cu o evoluție postoperatorie favorabilă. Concluzie. Abordul laparoscopic are aceleași indicații ca abordul clasic conform EAES, cu avantajul complicațiilor perioperatorii mult reduse și o spitalizare postoperatorie mai mică comparativ cu abordul clasic, iar în cazul echipelor experimentate este posibil abordul laparoscopic inclusiv la pacienții cu splenomegalii masive (>20cm), care poate fi asistat manual.Aim of study. Study of cases of splenectomy by laparoscopic and classic approach in order to establish causality type procedureperioperative incidents and demonstrate the superiority of the laparoscopic approach. Materials and methods. The cases of splenectomy performed by classical and laparoscopic approach in the Colțea Surgery Clinic, period 01.01.2019-31.12.2022, were selected. We reviewed intraoperative films, assessed general and local factors associated with the preferred surgical approach. Results. 29 cases were selected, average age 54.8 years, 72.4% women, 27.6% men, 55.2% (16) with multiple comorbidities: major surgical antecedents, heart failure, severe bronchial asthma, etc. The cases were divided into 2 groups: Gr. I- with laparoscopic approach 34.5% (10), Gr. II- with classic approach 65.5% (19). The incidence of comorbidities was 10% (1) in Gr.I, with mean spleen size of 13.2 cm (min 8.5 cm, max 21 cm) and 84.2% (16) in Gr.II with mean spleen size of 20.4 cm (min 10 cm, max 34 cm). Only in Gr.II, intraoperative bleeding was recorded in 78.9% (15), and in 15.8% (3) there were postoperative complications. The patients in Gr. I had an average postoperative hospitalization period of 4 days, and those in Gr. II of 7 days, and were discharged with a favorable postoperative evolution. Conclusions. The laparoscopic approach has the same indications as the classic one according to EAES, with the advantage of reduced perioperative complications and a shorter postoperative hospitalization, and in the case of experienced teams, the laparoscopic approach is possible, including patients with massive splenomegaly (>20cm), being manually assisted