Peat leachmound treatment of residential wastewater in sub-Arctic Alaska     

Raymond Z. Riznyk  Julius Rockwell Jr.  Leroy C. Reid Jr.  Sabra L. Reid 《Water, air, and soil pollution》1993,69(1-2):165-177

In many areas of the North, conventional septic systems cannot be installed or have failed because of inadequate drainage. Conventional domestic, on-site wastewater may contaminate shallow water tables and surface waters. The effectiveness of two pilot peat leachfields in treating septic wastewater was investigated for approximately two years by comparing the quality of the untreated wastewater collected from the septic system lift stations to the quality of the peat leachate. The quality of the leachate, based on parameters such as BOD, COD, TSS, NO₃-N, TKN, total-P, pH, fecal and total coliform bacteria, color, turbidity, and DO, is similar to wastewater that has undergone tertiary treatment. Temperatures below the leachmound distribution pipes ranged between 1° and 6 °C. Clogging of the interstices with an organic slime was not encountered. The results of the study show that peat leachmounds can be adopted to treat residential wastewater in rural sub-Arctic Alaska and other northern tier countries without compromising ground or surface water quality.  相似文献   

Late Holocene erosion in NW Anatolia from sediments of Lake Manyas, Lake Ulubat and the southern shelf of the Marmara Sea, Turkey   总被引：1，自引：0，他引：1  

N. Kazanc&#x;  S. Leroy   . Ileri   . Emre  M. Kibar  S. ncel 《CATENA》2004,57(3):277-308

This paper deals with modern and ancient sedimentation in fresh water lakes and the marine shelf of the southern Marmara region, NW Anatolia, Turkey. Most of the information has been obtained from monitoring of suspended load discharged into two lakes (Manyas and Ulubat) in the last 45 years and from 8 to 11 m thick lacustrine sediments, in addition to radiocarbon-dated shelf sediments. This allows a holistic approach to the drainage basin denudation over time. The results show that the sedimentation rates in the lakes were low 0.22 cm year⁻¹, from 4000 to 2000 years BP and then they increased (0.29 cm year⁻¹) up to sub-recent times and reached 0.44 cm year⁻¹ in the last century. It is suggested that deforestation created high rates of sedimentation in the basins and/or strong denudation of the region during the Late Holocene. This study also shows that for shallow freshwater lakes the calculation of sedimentation rates must include fine particles lost by the outlets and coarse-grained bed load deposited on their shores. In addition, a high rate of sedimentation has been created by short, but repetitive intense depositions. During the last century particularly during the last 45 years, the rate of sedimentation or denudation has increased dramatically in NW Turkey. The two World Wars and mismanagement of the land had important local effects by increasing deforestation and resulting in the present erosive conditions.  相似文献   

Chronic effects of low ph and elevated aluminum on survival,maturation, spawning and embryo-larval development of the fathead minnow in soft water     

J. Howard McCormick  Kathleen M. Jensen  Leroy E. Anderson 《Water, air, and soil pollution》1989,43(3-4):293-307

Fathead minnows (Pimephales promelas) were exposed to a range of pH and A1 concentrations in soft water (8 mg Ca L^?1) to determine effect levels at various life stages. The tested pH levels ranged from 8.0 through 5.2 and inorganic monomeric Al from 15 through 60 μg L^?1. Reproductive processes including spawning, embryogenesis and early larval survival were more sensitive to acid stress than were juvenile growth and survival. Juvenile survival was significantly reduced at pH 5.2 + 60 μg Al L^?1 (P <0.05). Spawning success was reduced at pH 6.0 and 5.5 (P <0.10) and failed completely at pH 5.2, regardless of Al concentration. An apparant beneficial effect of added Al was observed during spawning at pH 7.5 + 35 μg Al L^?1, but this effect was not significantly greater than at pH 7.5 + 15 μg Al L^?1. A significant (P <0.05) decrease in larval survival occurred at pH 6.0 + 15 μg Al L^?1 and lower compared to the survival at pH 7.5 + 15 μg Al L^?1. Aluminum at 30 μg L^?1 provided protection resulting in short term increased embryo-larval survival at pH 5.5. The effect of parental exposure on progeny survival was assessed by an interchange of embryos from the spawning treatment to all tested exposure conditions. When reared at pH 8.0 + 15 μg Al L^?1 through 6.0 + 15 μg Al L^?1 or at pH 5.5 + 30 μg Al L^?1, parental exposure did not significantly influence progeny survival. However, survival was significantly reduced among progeny from brood fish reared at pH 5.5 + 15 μg Al L^?1 as compared to those spawned at pH 6.0 + 15 μg Al L^?1 and above, or at pH 5.5 + 30 μg Al L^?1 (P <0.05). Juvenile or 14 d larval growth effects were not detected under any exposure condition (P >0.05). Ultimately, fathead minnow young-of-the-year recruitment and production potential can be expected to diminish when environmental pH falls to 6.0, and to fail completely at 5.5 and lower.  相似文献   

Chemical Composition of Rainwater Near Two Historical Monuments The Thann Collegiate (Alsace,France) and the Tours Cathedral (Indre et Loire,France)     

Millet  Maurice  Wortham  Henri  Mirabel  Philippe  Flori  Jean-Paul  Lakkis  Dominique  Leroy  Maurice 《Water, air, and soil pollution》2001,132(1-2):105-126

In the present study, included within the framework of a Franco-German Research Program for Conservation of HistoricalMonuments, the chemical composition of rainwater was investigated in Thann (Alsace, France) and in Tours (Indre etLoire, France) between 1992 and 1993. A total of 78 and 24samples, respectively, were collected, near the Thann collegiateand the Tours cathedral on a weekly basis and analysed for Cl^-, NO₃ ^-, SO₄ ^2-, Na⁺, NH₄ ⁺, K⁺, Mg²⁺ and Ca²⁺. Results showpH ranged from 3.60 to 6.58 and from 5.49 to 7.01 for Thann andTours, respectively. In Thann, SO₄ ^2- is the major anion and rainwater acidity is neutralised by compounds ofterrigenic origin which come from the soil of the upper Rhinevalley (Ca²⁺; ‘loess’) and the potash mines of Alsace. In Tours, SO₄ ^2- is also the major anion and the acidity is neutralised partially by atmospheric ammonia and partially by compounds of terrigenic origin and by dust fromthe erosion of the cathedral and the works of restoration, in the form of CaCO₃.  相似文献   

Plant Age and Growing Season Nutritional Content Relationships of Three Artemisia tridentata Subspecies     

Barry L. Perryman  Teshome Shenkoru  Leroy B. Bruce  Hussein S. Hussein 《Strength and Conditioning Journal》2011,64(1):78-84

The effect of plant age on growing season chemical compositions and rumen fermentation characteristics was determined for three subspecies of big sagebrush: basin (Artemisia tridentata [Nutt.] subsp. tridentata), mountain (A. tridentata subsp. vaseyana [Rybd.] Beetle), and Wyoming (A. tridentata subsp. wyomingensis [Beetle and Young]). In vitro dry matter (IVDMD) and organic matter (IVOMD) disappearance, ammonia nitrogen (NH₃N), and volatile fatty acid (VFA) content were determined at the end of two fermentation periods (24 h and 48 h) by combining rumen inocula with age-classified vegetative samples from each sagebrush subspecies. An additional one-way analysis of variance was performed to investigate potential differences among subspecies in IVDMD, IVOMD, total VFA, and NH₃N following a 48-h fermentation period. Crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) components were also compared among sagebrush subspecies. Age class responses were variable across the spectrum of sagebrush subspecies and response variables. Where plant age effects were indicated, the small numeric differences probably have little biological or ecological significance. Mountain sagebrush was lower in IVOMD and total VFA concentrations (P < 0.0001) than basin and Wyoming. NH₃N concentration and CP were higher (P < 0.0001) in basin sagebrush than the other two subspecies, while Wyoming sagebrush was higher in NDF, ADF, and ADL than basin and mountain subspecies (P < 0.0001). NH₃N concentration for all three subspecies was lower than the minimum level (20 mg · 100 mL^?1) required for uninhibited rumen activity. Overall, this research questions the contention that older sagebrush plants offer less nutritional value than younger ones, at least for growing season conditions. The results also provide information that can be utilized in designing supplementation strategies for domestic animals on diets with characteristically high utilization of big sagebrush.  相似文献   

Whole-genome shotgun assembly and analysis of the genome of Fugu rubripes   总被引：2，自引：0，他引：2  

Aparicio S  Chapman J  Stupka E  Putnam N  Chia JM  Dehal P  Christoffels A  Rash S  Hoon S  Smit A  Gelpke MD  Roach J  Oh T  Ho IY  Wong M  Detter C  Verhoef F  Predki P  Tay A  Lucas S  Richardson P  Smith SF  Clark MS  Edwards YJ  Doggett N  Zharkikh A  Tavtigian SV  Pruss D  Barnstead M  Evans C  Baden H  Powell J  Glusman G  Rowen L  Hood L  Tan YH  Elgar G  Hawkins T  Venkatesh B  Rokhsar D  Brenner S 《Science (New York, N.Y.)》2002,297(5585):1301-1310

The compact genome of Fugu rubripes has been sequenced to over 95% coverage, and more than 80% of the assembly is in multigene-sized scaffolds. In this 365-megabase vertebrate genome, repetitive DNA accounts for less than one-sixth of the sequence, and gene loci occupy about one-third of the genome. As with the human genome, gene loci are not evenly distributed, but are clustered into sparse and dense regions. Some "giant" genes were observed that had average coding sequence sizes but were spread over genomic lengths significantly larger than those of their human orthologs. Although three-quarters of predicted human proteins have a strong match to Fugu, approximately a quarter of the human proteins had highly diverged from or had no pufferfish homologs, highlighting the extent of protein evolution in the 450 million years since teleosts and mammals diverged. Conserved linkages between Fugu and human genes indicate the preservation of chromosomal segments from the common vertebrate ancestor, but with considerable scrambling of gene order.  相似文献   

A human Y-linked DNA polymorphism and its potential for estimating genetic and evolutionary distance   总被引：29，自引：0，他引：29  

M Casanova  P Leroy  C Boucekkine  J Weissenbach  C Bishop  M Fellous  M Purrello  G Fiori  M Siniscalco 《Science (New York, N.Y.)》1985,230(4732):1403-1406

A human DNA sequence (p12f2), derived from a partial Y-chromosome genomic library and showing homology with the X and Y chromosomes and with an undetermined number of autosomes, detected two Y-specific restriction fragment length variants on male DNA that had been digested with Taq I and Eco RI. These variants may have been generated through a deletion-insertion mechanism and their pattern of holoandric transmission indicates that they represent a two-allele Y-linked polymorphism (RFLP). By means of DNA from patients with inborn deletions in chromosome Y, this polymorphic DNA site was mapped to the interval Yq11.1-Yq11.22. The frequency of the rarest allele was about 35 percent in Algerian and Sardinian human males, whereas it was only 4 percent among Northern Europeans. The p12f2 probe also detected Y-specific DNA fragments in the gorilla and chimpanzee. In view of the monosomy of the Y chromosome in mammalian species, Y-linked RFLP's may prove to be more useful than autosomal or X-linked markers in estimating genetic distances within and between species.  相似文献   

The IL-10 homologue encoded by cyprinid herpesvirus 3 is essential neither for viral replication in vitro nor for virulence in vivo     

Ping Ouyang  Krzysztof Rakus  Maxime Boutier  Anca Reschner  Baptiste Leroy  Maygane Ronsmans  Guillaume Fournier  Sophie Scohy  Bérénice Costes  Ruddy Wattiez  Alain Vanderplasschen 《Veterinary research》2013,44(1):53

  相似文献   

Normal Canine Prostate Gland: Repeatability,Reproducibility, Observer‐Dependent Variability of Ultrasonographic Measurements of the Prostate in Healthy Intact Beagles     

C. Leroy  F. Conchou  C. Layssol‐Lamour  A. Deviers  J. Sautet  D. Concordet  G. Mogicato 《Anatomia, histologia, embryologia》2013,42(5):355-361

Most prostatic diseases in dogs are associated with prostatomegaly, and transabdominal ultrasonography has become the imaging modality of choice for evaluation of the prostate gland in the dog. The aim of the present study was to assess the reproducibility, the repeatability and interobserver variations of sonographic measurements of prostate and to determine which measurement had the lowest variability. Length and height of prostate gland were measured on longitudinal views, width of the prostate gland and height of left and right lobes of the gland on transversal views. The within‐day and between‐day variabilities of the prostatic parameters were determined by performing 1350 (270 length, 270 height, 270 width, 270 height of right lobe and 270 height of left lobe) examinations on ten healthy intact beagle dogs on six different days, in a two‐week period (three days for the five dogs, three different days for the five others). Three observers with different levels of experience in ultrasonography performed the examinations. The lowest within‐day and between‐day standard deviation and coefficient of variation values were observed for the width of the prostate. The width of the gland measured on transverse frozen images seems to be the most reliable measurement for evaluating size of prostate glands in healthy dogs, although the shape, position, outline, and echogenicity of the prostate should also be assessed.  相似文献   

An alternative rotational stocking management designed to favour butterflies in permanent grasslands     

A. Farruggia  B. Dumont  A. Scohier  T. Leroy  P. Pradel  J.‐P. Garel 《Grass and Forage Science》2012,67(1):136-149

Grassland butterflies are on the decline throughout Europe. We tested an ‘alternative rotational stocking’ (ARS) strategy based on theoretical and practical aspects of grassland ecology, designed to increase butterfly diversity while also meeting farmers’ production objectives. This management strategy implies taking animals away from one subplot of the rotation during the main flowering period. Its feasibility and benefits on butterfly diversity were tested by comparing ARS with continuous stocking (CS) in plots grazed by cattle at the same stocking rate: high in 2005 and 2006 then lenient in 2007 and 2008. At the high stocking rate, butterfly abundance (21·9 vs. 8·3, P < 0·01) and butterfly species richness (7·4 vs. 3·7, P < 0·001) were significantly higher in ARS than in CS plots, matching the increase in pasture flowering intensity and sward structural diversity. ARS was led according to the pre‐planned schedule in 2005, but in 2006, the number of heifer grazing days in ARS was reduced by 19% because of unfavourable spring grass growth. At the lenient stocking rate, ARS was less beneficial for butterflies (abundance: 17·4 vs. 13·0, P < 0·10; species richness: 5·9 vs. 5·2, P = 0·35) but would present less risk for farmers in terms of providing livestock with sufficient forage. Alternative rotational stocking thus has potential to be integrated into grassland‐based systems, but would require earlier grazing on the excluded subplot of the rotation in the event of unfavourable grass growth during spring.  相似文献