Chemical weathering and CO2 consumption in the upper Nyong Basin rivers (Central Africa): Insights on climatic and anthropogenic forcing in humid tropical environments.

A hydrological and hydrochemical database (produced by the M-TROPICS critical zone observatory) in the upper Nyong Basin from 1998 to 2017 was used to evaluate the river's response to climatic and anthropogenic forcing and examine chemical weathering processes. SiO2 and HCO3- constitute about 85 % of the Total dissolved solids (TDS) load, equivalent to 0.12 × 109 kg. y-1. Electrical conductivity (EC), Total dissolved solids (TDS), major cations, major anions (except F- and NO3-) and alkalinity (Alk) vary seasonally and follow a predictable model with discharge. Atlantic Meridional Mode oscillation controls the long-term water chemistry. Atmospheric input and silicate weathering are the main factors influencing the Nyong rivers chemistry. However, several indices supported the progressive water quality deterioration by human activities, namely: the excess of Cl- and SO42- after the substraction of atmospheric inputs, the basic pH observed for specific samples, long-term increase in the values of pH, EC, TDS, EC, Mg2+, Ca2+, F-, NO3-, HCO3-, Alk, SiO2 and Dissolved Organic Carbon. Runoff and physical erosion have an important control on chemical erosion in the upper Nyong Basin rivers. The chemical erosion rate (3.3 t.km-2.y-1) equals the silicate weathering rate. The CO2 consumption rate, in the Nyong rivers, is lower than the global average (98× 103 for silicate weathering and 246 × 103 mol.km-2.y-1 for chemical erosion) and estimated at 52.3 × 103 for silicate weathering and 54.1 × 103 mol.km-2.y-1 for chemical erosion. At Olama, the most downstream location of the monitoring setup, the Nyong River Basin consumed 1 × 109 mol.y-1 of CO2 by chemical erosion.

Quality of hematology and clinical chemistry results in laboratory and zoo nonhuman primates: Effects of the preanalytical phase. A review.

Most errors in clinical pathology originate in the preanalytical phase, which includes all steps from the preparation of animals and equipment to the collection of the specimen and its management until analyzed. Blood is the most common specimen collected in nonhuman primates. Other specimens collected include urine, saliva, feces, and hair. The primary concern is the variability of blood hematology and biochemistry results due to sampling conditions with the effects of capture, restraint, and/or anesthesia. Housing and diet have fewer effects, with the exception of food restriction to reduce obesity. There has been less investigation regarding the impact of sampling conditions of nonblood specimens.

Socio-Ecological Approach to a Forest-Swamp-Savannah Mosaic Landscape Using Remote Sensing and Local Knowledge: a Case Study in the Bas-Ogooué Ramsar Site, Gabon.

Studies of landscape dynamics in protected areas often rely exclusively on remotely-sensed data, leading to bias by neglecting how local inhabitants, who often have a long history of interaction with their environment, perceive and structure the landscape over time. Using a socio-ecological system (SES) approach in a forest-swamp-savannah mosaic within the Bas-Ogooué Ramsar site in Gabon, we assess how human populations participate in landscape dynamics over time. We first conducted a remote sensing analysis to produce a land-cover map representing the biophysical dimension of the SES. This map is based on pixel-oriented classifications, using a 2017 Sentinel-2 satellite image and 610 GPS points, that categorized the landscape in 11 ecological classes. To study the landscape's social dimension, we collected data on local knowledge to understand how local people perceive and use the landscape. These data were collected through 19 semi-structured individual interviews, three focus groups and 3 months of participant observation during an immersive field mission. We developed a systemic approach by combining data on biophysical and social dimensions of the landscape. Our analysis shows that in the absence of continued anthropic interventions, both savannahs and swamps dominated by herbaceous vegetation will experience closure by encroaching woody vegetation, leading to eventual biodiversity loss. Our methodology based on an SES approach to landscapes could improve the conservation programs developed by Ramsar site managers. Designing actions at the local scale, rather than applying one set of actions to the entire protected area, allows the integration of human perceptions, practices and expectations, a challenge that is more than essential in the context of global change.

Topography of mountain belts controlled by rheology and surface processes.

It is widely recognized that collisional mountain belt topography is generated by crustal thickening and lowered by river bedrock erosion, linking climate and tectonics1-4. However, whether surface processes or lithospheric strength control mountain belt height, shape and longevity remains uncertain. Additionally, how to reconcile high erosion rates in some active orogens with long-term survival of mountain belts for hundreds of millions of years remains enigmatic. Here we investigate mountain belt growth and decay using a new coupled surface process5,6 and mantle-scale tectonic model7. End-member models and the new non-dimensional Beaumont number, Bm, quantify how surface processes and tectonics control the topographic evolution of mountain belts, and enable the definition of three end-member types of growing orogens: type 1, non-steady state, strength controlled (Bm > 0.5); type 2, flux steady state8, strength controlled (Bm ≈ 0.4-0.5); and type 3, flux steady state, erosion controlled (Bm < 0.4). Our results indicate that tectonics dominate in Himalaya-Tibet and the Central Andes (both type 1), efficient surface processes balance high convergence rates in Taiwan (probably type 2) and surface processes dominate in the Southern Alps of New Zealand (type 3). Orogenic decay is determined by erosional efficiency and can be subdivided into two phases with variable isostatic rebound characteristics and associated timescales. The results presented here provide a unified framework explaining how surface processes and lithospheric strength control the height, shape, and longevity of mountain belts.

Improving the Quality of EDTA-treated Blood Specimens from Mice.

Nonterminal blood sampling in laboratory mice is a very common procedure. With the goal of improving animal welfare, different sampling sites and methods have been compared but have not achieved a consensus. Moreover, most of these studies overlooked the quality of blood specimens collected. The main preanalytical concern with EDTA-treated blood specimens for hematology analyses is platelet aggregation, which is known to cause analytical errors. Our objective was to find a nonterminal blood sampling method with minimal adverse effects on mice and few or no platelet aggregates. We tested and compared 2 collection sites, 4 sampling methods, and 3 antithrombotic drugs in 80 C57BL6/j male and female mice by evaluating platelet aggregates on blood smears and platelet, WBC, and RBC counts. In addition, the blood collection process was carefully evaluated, and adverse effects were recorded. Platelet aggregation was lower in specimens collected from the jugular vein than from the facial vein, with no effect of the sampling device or the presence of an antithrombotic additive. Highly aggregated specimens were significantly associated with lower platelet counts, whereas aggregation had no effect on WBC or RBC counts. Adverse events during sampling were significantly associated with more numerous platelet aggregates. The jugular vein is thus a satisfactory sampling site in mice in terms of both animal welfare and low platelet aggregation. Using antithrombotic agents appears to be unnecessary, whereas improving sampling conditions remains a key requirement to ensure the quality of EDTA-treated blood specimens from mice.

Ecological plasticity to ions concentration determines genetic response and dominance of Anopheles coluzzii larvae in urban coastal habitats of Central Africa.

In Central Africa, the malaria vector Anopheles coluzzii is predominant in urban and coastal habitats. However, little is known about the environmental factors that may be involved in this process. Here, we performed an analysis of 28 physicochemical characteristics of 59 breeding sites across 5 urban and rural sites in coastal areas of Central Africa. We then modelled the relative frequency of An. coluzzii larvae to these physicochemical parameters in order to investigate environmental patterns. Then, we assessed the expression variation of 10 candidate genes in An. coluzzii, previously incriminated with insecticide resistance and osmoregulation in urban settings. Our results confirmed the ecological plasticity of An. coluzzii larvae to breed in a large range of aquatic conditions and its predominance in breeding sites rich in ions. Gene expression patterns were comparable between urban and rural habitats, suggesting a broad response to ions concentrations of whatever origin. Altogether, An. coluzzii exhibits a plastic response to occupy both coastal and urban habitats. This entails important consequences for malaria control in the context of the rapid urban expansion in Africa in the coming years.

Validation of the Sysmex XN-V hematology analyzer for canine specimens.

BACKGROUND: The Sysmex XN-V is derived from the new Sysmex XN series of human hematology analyzers. The main changes from the previously validated XT-2000iV analyzer include an optic-fluorescent analysis for platelets and nucleated RBC count. OBJECTIVE: We aimed to validate the Sysmex XN-V for canine blood according to American College for Veterinary Clinical Pathology and International Council for Standardization in Hematology recommendations. MATERIALS AND METHODS: Canine EDTA blood specimens and quality control material were analyzed on the Sysmex XN-V to evaluate imprecision, bias, linearity, a comparison with the XT-2000iV analyzer, interference effects, carry-over, and stability. We also verified previously established Sysmex XT-2000iV reference intervals (RIs). RESULTS: Imprecision and bias were low (<5%) for most variables. Observed total error was lower than allowable total error for most measured variables except lymphocytes and monocytes. Visually determined linearity was excellent for all variables, except for lymphocytes. The correlation between the XN-V and XT-2000iV analyzers was high (>0.93) for all variables except MCHC and reticulocyte indices. Correlations between the Sysmex XN-V and manual differential counts were good for neutrophils and eosinophils, acceptable for lymphocytes, and fair for monocytes. Hemolysis, lipemia, and to a lesser extent icterus, had significant effects on measured hemoglobin concentration and associated variables. Carry-over was not visually observed for any variable. Changes in the Sysmex XN-V measurements after storage at 4℃ and 24℃ were similar to those described for the Sysmex XT-2000iV analyzer. The previously established Sysmex XT-2000iV RIs can be used to interpret results from the Sysmex XN-V analyzer for most variables except red blood cell distribution width and mean platelet volume. CONCLUSIONS: The performance of the Sysmex XN-V analyzer was excellent and compared favorably with the Sysmex XT-2000iV analyzer.

Reference Values for Hematology, Plasma Biochemistry, Bone Marrow Cytology and Bone Histology of NOD.Cg-Prkdcscid Il2rgtm1Wjl/ SzJ Immunodeficient Mice.

Highly immunodeficient NSG mice (NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ) are commonly used as a models in preclinical studies for patient-derived engraftment. However, despite the frequency of their use, reference values for their clinical pathology markers have not been determined. In accordance with the American Society of Veterinary Clinical Pathology (ASVCP) recommendations, we established de novo reference values for hematologic and biochemical variables and evaluated bone marrow cytology and histology in forty 9-wk-old male and female NSG mice. Hematologic analyses were performed using 2 separate analyzers (IDEXX ProCyte Dx, Sysmex XT-2000iV) and biochemical values were measured using a Scil VetScan2. The primary hematologic characteristic seen in NSG mice was a very low white blood cell (WBC) count (below 1.6 109/L). Lymphocyte and monocyte counts were respectively over- and under-estimated by the analyzers, as compared with manual counts, likely due to misidentification of the very low concentrations of these cell types by the analyzers. This analytical bias highlights the need for confirmatory microscopic observation of blood smears from these mice for WBC differential identification. Results for all other hematology and biochemistry variables were similar to those previously reported in inbred mice, except for MPV and an unexpectedly high glucose concentration (11.5 to 19.0 mmol/L), potentially due to the nonfasting status of the animals. The differential bone marrow cell count and Myeloid:Erythroid ratio (median 1.76) were also established. Megakaryocyte and adipocyte count differed significantly between the femoral diaphysis and metaphysis and between genders. These results provide a reliable resource of baseline data for hematologic variables for researchers monitoring graft rejection studies in NSG mice.

Reproduction Function in Male Patients With Bardet Biedl Syndrome.

PURPOSE: Bardet-Biedl syndrome (BBS) is a ciliopathy with a wide spectrum of symptoms due to primary cilia dysfunction, including genitourinary developmental anomalies as well as impaired reproduction, particularly in males. Primary cilia are known to be required at the following steps of reproduction function: (i) genitourinary organogenesis, (ii) in fetal firing of hypothalamo-pituitary axe, (iii) sperm flagellum structure, and (iv) first zygotic mitosis conducted by proximal sperm centriole. BBS phenotype is not fully understood. METHODS: This study explored all steps of reproduction in 11 French male patients with identified BBS mutations. RESULTS: BBS patients frequently presented with genitourinary malformations, such as cryptorchidism (5/11), short scrotum (5/8), and micropenis (5/8), but unexpectedly, with normal testis size (7/8). Ultrasonography highlighted epididymal cysts or agenesis of one seminal vesicle in some cases. Sexual hormones levels were normal in all patients except one. Sperm numeration was normal in 8 out of the 10 obtained samples. Five to 45% of sperm presented a progressive motility. Electron microscopy analysis of spermatozoa did not reveal any homogeneous abnormality. Moreover, a psychological approach pointed to a decreased self-confidence linked to blindness and obesity explaining why so few BBS patients express a child wish. CONCLUSIONS: Primary cilia dysfunction in BBS impacts the embryology of the male genital tract, especially epididymis, penis, and scrotum through an insufficient fetal androgen production. However, in adults, sperm structure does not seem to be impacted. These results should be confirmed in a greater BBS patient cohort, focusing on fertility.

The effects of storage at 4°C and 20°C on the hemograms of C57BL/6 mice and Wistar rats using the IDEXX ProCyte Dx and blood smear evaluations.

BACKGROUND: Delayed blood analysis might be unavoidable in laboratory practice, but little is known about rodent blood stability, especially cell morphology and scattergram results. OBJECTIVES: This study aimed to evaluate the stability of rodent blood cell counts and morphologies at different temperatures using the ProCyte Dx analyzer and performing manual observations. METHODS: Ten Wistar rats and 10 C57bl/6 mice were sampled on EDTA tubes and aliquoted for storage (4°C, 20°C). Hematologic analyses were performed immediately and at T6h, T24h, T48h (rats and mice), and T72h (rats only) after storage. RESULTS: In rats, at any temperature, red blood cell counts, hemoglobin concentrations (HGB), mean corpuscular hemoglobin (MCH) levels, and reticulocyte, white blood cell (WBC), eosinophil, and impedance platelet counts remained stable over time. The main changes were observed at 20°C for hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and WBC differential counts. Optical platelet counts (PLT-O) and platelet variables underwent changes at both temperatures from T24h. In mice, red blood cell counts by impedance (RBC-I), MCH, and WBC, lymphocyte, eosinophil, and platelet counts, and plateletcrit (PCT) were stable over time and at all temperatures. As in rats, the most significant changes were observed at 20°C and concerned the optical RBC (RBC-O) counts, HCTs, MCVs, MCHCs, and reticulocyte, neutrophil, and monocyte counts. For both species, blood cell morphologies were altered from T24h at all temperatures, and platelet clumps were more numerous at 4°C. CONCLUSIONS: When rodent blood analyses need to be delayed, storage at 4°C is preferred and should not exceed 24 hours. PLT counts should be interpreted cautiously in refrigerated specimens with mandatory blood smear evaluations when abnormal scattergrams are observed.

Urinalysis and determination of the urine protein-to-creatinine ratio reference interval in healthy cows.

BACKGROUND: There are no reference intervals for urinalysis in cattle. HYPOTHESIS/OBJECTIVES: Characterize the urine of healthy cows, establish urine protein-to-creatinine ratio (UPC) reference intervals, and test possible differences among dairy and beef cattle, age groups, or stage of lactation. ANIMALS: Seventy-seven dairy and 74 beef 2.5 to 17 year-old cows of different breeds housed mainly in free stall. METHODS: In this prospective study, urine specimens were collected by catheterization. Complete urinalysis was performed within 1 hour including specific gravity, dipstick evaluation, visual urine pH evaluation with 0.3 pH unit graded strips, and microscopic evaluation of the sediment. Urinary protein and creatinine concentrations and protein electrophoresis were determined on frozen aliquots. RESULTS: Overall reference intervals were 1.020 to 1.045 for USG, 7.0 to 8.7 for pH, and 0.04 to 0.25 for UPC; because of differences in creatinine concentration, UPC was lower in beef (0.04-0.14) than in dairy (0.05-0.25) cows and in the latter in dry than lactating cows. With dipstick evaluation, most analytes were absent except for blood, ketone, and protein in 24.7, 16.0, and 64.7% of cases, respectively. Microscopic evaluation revealed less than 3 red blood cells, leukocytes, and epithelial cells in 84, 99.3, and 100% cows, respectively. No band was observed at electrophoresis, except in 1 case at MW ~66 000. CONCLUSIONS AND CLINICAL IMPORTANCE: Creatininuria is higher in beef than dairy cows and proteinuria is likely more efficiently characterized by protein concentration than by UPC.

Glacial Steady State Topography Controlled by the Coupled Influence of Tectonics and Climate.

Glaciers and rivers are the main agents of mountain erosion. While in the fluvial realm empirical relationships and their mathematical description, such as the stream power law, improved the understanding of fundamental controls on landscape evolution, simple constraints on glacial topography and governing scaling relations are widely lacking. We present a steady state solution for longitudinal profiles along eroding glaciers in a coupled system that includes tectonics and climate. We combined the shallow ice approximation and a glacial erosion rule to calculate ice surface and bed topography from prescribed glacier mass balance gradient and rock uplift rate. Our approach is inspired by the classic application of the stream power law for describing a fluvial steady state but with the striking difference that, in the glacial realm, glacier mass balance is added as an altitude-dependent variable. From our analyses we find that ice surface slope and glacial relief scale with uplift rate with scaling exponents indicating that glacial relief is less sensitive to uplift rate than relief in most fluvial landscapes. Basic scaling relations controlled by either basal sliding or internal deformation follow a power law with the exponent depending on the exponents for the glacial erosion rule and Glen's flow law. In a mixed scenario of sliding and deformation, complicated scaling relations with variable exponents emerge. Furthermore, a cutoff in glacier mass balance or cold ice in high elevations can lead to substantially larger scaling exponents which may provide an explanation for high relief in high latitudes.

Hematology reference intervals for adult cows in France using the Sysmex XT-2000iV analyzer.

In order to develop bovine hematology reference intervals (RIs) in accordance with new international recommendations, we analyzed 156 blood specimens of healthy adult dairy and beef cows from 32 farms with a Sysmex XT-2000iV analyzer, and by manual scoring of platelet clumps and white blood cell (WBC) differential. We established RIs by the nonparametric method, and examined effects of age, production type (beef vs. dairy), and stage of lactation. RIs could not be determined for platelet count and indices because clumps were observed in 80% of specimens. Optical and impedance red blood cell (RBC) counts were similar, although statistically different. RIs for analyzer and manual WBC differentials were not different except for lymphocyte concentration, the subpopulations of which were counted manually. Hematocrit was higher in beef than dairy cattle, and hemoglobin was lower in early lactation. Increases in RBC count, mean corpuscular volume, mean corpuscular hemoglobin, and RBC distribution width were noted with increasing age, along with decreases in WBC count, neutrophils, and lymphocytes. Most RIs in our study, with the exception of neutrophils, were similar to those previously reported using a flow cytometry analyzer.

Polar pesticide contamination of an urban and peri-urban tropical watershed affected by agricultural activities (Yaoundé, Center Region, Cameroon).

Urban agriculture is crucial to local populations, but the risk of it contaminating water has rarely been documented. The aim of this study was to assess pesticide contamination of surface waters from the Méfou watershed (Yaoundé, Cameroon) by 32 selected herbicides, fungicides, and insecticides (mainly polar) according to their local application, using both grab sampling and polar organic compounds integrative samplers (POCIS). Three sampling campaigns were conducted in the March/April and October/November 2015 and June/July 2016 rainy seasons in urban and peri-urban areas. The majority of the targeted compounds were detected. The quantification frequencies of eight pesticides were more than 20% with both POCIS and grab sampling, and that of diuron and atrazine reached 100%. Spatial differences in contamination were evidenced with higher contamination in urban than peri-urban rivers. In particular, diuron was identified as an urban contaminant of concern because its concentrations frequently exceeded the European water quality guideline of 0.200 µg/L in freshwater and may thus represent an ecological risk due to a risk quotient > 1 for algae observed in 94% of grab samples. This study raises concerns about the impacts of urban agriculture on the quality of water resources and to a larger extent on the health of the inhabitants of cities in developing countries. Graphical abstract ᅟ.

Sculpting Mountains: Interactive Terrain Modeling Based on Subsurface Geology.

Most mountain ranges are formed by the compression and folding of colliding tectonic plates. Subduction of one plate causes large-scale asymmetry while their layered composition (or stratigraphy) explains the multi-scale folded strata observed on real terrains. We introduce a novel interactive modeling technique to generate visually plausible, large scale terrains that capture these phenomena. Our method draws on both geological knowledge for consistency and on sculpting systems for user interaction. The user is provided hands-on control on the shape and motion of tectonic plates, represented using a new geologically-inspired model for the Earth crust. The model captures their volume preserving and complex folding behaviors under collision, causing mountains to grow. It generates a volumetric uplift map representing the growth rate of subsurface layers. Erosion and uplift movement are jointly simulated to generate the terrain. The stratigraphy allows us to render folded strata on eroded cliffs. We validated the usability of our sculpting interface through a user study, and compare the visual consistency of the earth crust model with geological simulation results and real terrains.

Effects of storage conditions on results for quantitative and qualitative evaluation of proteins in canine urine.

OBJECTIVE To investigate effects of storage conditions on the canine urine protein-to-creatinine ratio (UPC) and on SDS-agarose gel electrophoresis (AGE) of urinary proteins. SAMPLE Urine specimens from 20 proteinuric (UPC > 0.5) and 20 nonproteinuric (UPC ≤ 0.2) dogs. PROCEDURES UPC and SDS-AGE were performed on urine specimens stored at room temperature (20°C) and 4°C for up to 5 days and at -20° and -80°C for up to 360 days; some specimens were subjected to 3 freeze-thaw cycles. Results were compared with those obtained for fresh urine specimens. RESULTS UPC was not affected by storage at room temperature or by freezing. A decrease in UPC was observed for specimens from nonproteinuric dogs after 5 days at 4°C (10%) and from both groups after 90 days at -20° and -80°C (≤ 20% and ≤ 15%, respectively). The SDS-AGE profiles revealed no visual changes regardless of duration of storage for specimens stored at room temperature, 4°C, and -80°C, except for 1 profile after 360 days at -80°C. Repeated freeze-thaw cycles did not affect SDS-AGE profiles. Appearance or strengthening of high-molecular-weight bands that could alter interpretation was evident in SDS-AGE profiles after storage at -20°C for ≥ 15 days (31/40 dogs). CONCLUSIONS AND CLINICAL RELEVANCE Storage of urine at -20° or -80°C for up to 1 year influenced the UPC without affecting clinical interpretation. Storage of urine specimens at -20°C impaired visual analysis of SDS-AGE. When SDS-AGE cannot be performed on fresh or recently refrigerated urine specimens, storage at -80°C is recommended.

Evaluation of CTAD (citrate-theophylline-adenosine-dipyridamole) as a universal anticoagulant in dogs.

CTAD (citrate-theophylline-adenosine-dipyridamole) has been shown to be an almost universal anticoagulant in human and feline medicine, allowing most hematology, coagulation, and biochemical analyses. Forty canine blood specimens were collected in CTAD, EDTA, heparin, and citrate for hematology, biochemistry, and coagulation analyses. CTAD partially limited platelet aggregation observed in EDTA blood smears. CTAD specimens gave similar and well-correlated results for most variables of a complete blood cell count, except for mean corpuscular volume, which was moderately higher, and mean corpuscular hemoglobin concentration, which was moderately lower in CTAD than in EDTA; reticulocyte and platelet indexes were poorly correlated. CTAD plasma gave similar results to citrate for fibrinogen, antithrombin, and D-dimers, and relatively similar results for prothrombin time, but activated partial thromboplastin time was poorly correlated. Triglycerides, cholesterol, glucose, total proteins, phosphate, iron, alanine aminotransferase, γ-glutamyl transferase, and lipase were similar and well correlated in CTAD and heparin plasmas. Urea, creatinine, albumin, alkaline phosphatase, amylase, and aspartate aminotransferase showed moderate-to-marked bias, but these variables could be measured in CTAD plasma if new reference intervals were determined. Creatine kinase activity, potassium, chloride, and total carbon dioxide measurements are not recommended in CTAD plasma. CTAD is a prospective candidate as an almost universal anticoagulant for routine hematology, some plasma coagulation, and many biochemistry variables in dogs. Definitive recommendations will require study of abnormal canine blood specimens.

Groundwater resource vulnerability and spatial variability of nitrate contamination: Insights from high density tubewell monitoring in a hard rock aquifer.

Agriculture has been increasingly relying on groundwater irrigation for the last decades, leading to severe groundwater depletion and/or nitrate contamination. Understanding the links between nitrate concentration and groundwater resource is a prerequisite for assessing the sustainability of irrigated systems. The Berambadi catchment (ORE-BVET/Kabini Critical Zone Observatory) in Southern India is a typical example of intensive irrigated agriculture and then an ideal site to study the relative influences of land use, management practices and aquifer properties on NO3 spatial distribution in groundwater. The monitoring of >200 tube wells revealed nitrate concentrations from 1 to 360mg/L. Three configurations of groundwater level and elevation gradient were identified: i) NO3 hot spots associated to deep groundwater levels (30-60m) and low groundwater elevation gradient suggest small groundwater reserve with absence of lateral flow, then degradation of groundwater quality due to recycling through pumping and return flow; ii) high groundwater elevation gradient, moderate NO3 concentrations suggest that significant lateral flow prevented NO3 enrichment; iii) low NO3 concentrations, low groundwater elevation gradient and shallow groundwater indicate a large reserve. We propose that mapping groundwater level and gradient could be used to delineate zones vulnerable to agriculture intensification in catchments where groundwater from low-yielding aquifers is the only source of irrigation. Then, wells located in low groundwater elevation gradient zones are likely to be suitable for assessing the impacts of local agricultural systems, while wells located in zones with high elevation gradient would reflect the average groundwater quality of the catchment, and hence should be used for regional mapping of groundwater quality. Irrigation with NO3 concentrated groundwater induces a "hidden" input of nitrogen to the crop which can reach 200kgN/ha/yr in hotspot areas, enhancing groundwater contamination. Such fluxes, once taken into account in fertilizer management, would allow optimizing fertilizer consumption and mitigate high nitrate concentrations in groundwater.

Hematologic and Biochemical Biologic Variation in Laboratory Cats.

The biologic variation associated with a clinical pathology result is important to consider before reference intervals (RI) are used. Most available RI are population-based RI, in which the analytical variability, interindividual variability, and intraindividual variability are confounded. In addition, when the intraindividual variability is considerably less than the interindividual variability, a population-based RI is insufficiently sensitive to detect changes in a subject over time. Here we determined the biologic variation and reference change value (RCV) of hematologic and biochemical variables in laboratory cats. Blood specimens from 14 (7 females and 7 males) overnight-fasted laboratory cats sampled 7 times (days 1, 2, 7, 14, 31, 42, and 100) were analyzed regarding hematology and biochemistry variables. For each variable, analytical, intraindividual, and interindividual coefficients of variation were estimated prior to calculation of the index of individuality and the RCV. RBC variables (count, Hgb, Hct, MCV, MCH, MCHC, and RBC distribution width) and 5 biochemical analytes (cholesterol, creatinine, triglycerides, ALP, and calcium) exhibited marked individuality, therefore indicating that subject-based reference intervals or RCV would be preferable when monitoring these variables in laboratory cats. Population-based RI were shown to be adequate for glucose and sodium, and both types of population and individual RI were similarly efficient for albumin, total protein, urea, ALT, AST, creatine kinase, chloride, carbon dioxide, iron, magnesium, inorganic phosphate, and potassium and reticulocyte, WBC, neutrophil, lymphocyte, monocyte, eosinophil, and platelet counts. The RCV determined in the present study provide a valuable tool for monitoring hematologic and biochemical variables in healthy laboratory cats.

A new, faster, and safe nasal provocation test method for diagnosing mite allergic rhinitis.

BACKGROUND: Diagnosing house dust mite (HDM) allergic rhinitis is difficult. The nasal provocation test (NPT) has been shown to be the most pertinent, but several methods are available. According to guidelines, the NPT requires a skin end-point titration and an objective measurement of nasal patency. Hence, NPT is time consuming and its use is limited. OBJECTIVE: To evaluate the sensitivity, specificity, and safety of a new, more rapid, and simple alternative NPT (NPT-R) to HDM. METHODS: Eighty-eight patients with from rhinitis (49 allergic to HDM and 39 controls with and without atopy) were included. Allergic rhinitis to HDM was confirmed by a "classic" NPT based on the Lebel score and rhinomanometry. After a period of 4 weeks, NPT-R was performed and only the clinical score was measured. RESULTS: The study population was young (mean ± SD, 27.7 ± 8.5 years old), composed mostly of women (61 vs 27 men), and 24% reported asthma. The sensitivity and specificity of NPT-R were 83.7% and 100%, respectively. The correlation between the NPTs was statistically significant (0.833, P < .0001, n = 88) and the 2 NPTs were completely safe. Performing NPT-R was more rapid (mean ± SD, 22 ± 8 minutes) than the classic NPT (97 ± 20 minutes). CONCLUSION: The NPT-R is safe and easier and faster than the classic NPT. This new method appears to be a very useful tool in the diagnosis of HDM allergic rhinitis when the diagnosis is uncertain or before initiating immunotherapy. TRIAL REGISTRATION: ClinicalTrials.gov, identifier NCT01485523.