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Background Biotin, a water-soluble B-vitamin, has been shown to have anti-inflammatory properties. A biotin-deficient diet was recently shown to induce a colitis-like phenotype in mice, alleviated by biotin substitution. Mice with DSS colitis showed biotin deficiency and significantly reduced levels of SDMT, a protein involved in biotin absorption. Oral biotin substitution reversed DSS colitis and induced remission by inhibiting NF-κB, a transcription factor that hinders inflammatory cytokine expression and plays a role in intestinal barrier integrity and IBD. We investigated for the first time a possible clinical role of biotin status in IBD. Methods In a comparative, cross-sectional study, serum samples of IBD patients were compared with samples of 80 healthy blood donors (40f;18-65y). CBC, albumin and hsCRP were determined by standard tests and samples assessed for presence/absence of inflammation (serum hsCRP, cutoff Results 138 IBD patients (67f;72 CD/66 UC;42.5±14.3y) were enrolled. Of these, 83/138 had inflammation (39f;43CD/40UC;42.5±14.6y) and 55/138 no inflammation (28f;29CD/26UC;42.5±13.9y). In IBD patients, mean serum 3HIAc levels were significantly higher vs. controls but similar with vs. without inflammation (Table 1). The reference serum 3HIAc level was calculated as 11.0–27.3 nmol/L from controls; biotin deficiency was defined as >27.3 nmol/L 3HIAc (90thPC), since no validated cut-off exists. Biotin deficiency in IBD patients was significantly greater than in controls (Table 1). Conclusion High serum 3HIAc levels were associated with IBD. In line with preclinical studies, biotin deficiency was more pronounced in IBD patients than controls. No relation was found with inflammatory activity or disease type. Our findings suggest that biotin may have a bigger role than thought in IBD; whether as a cause or effect in IBD pathogenesis warrants investigation. Routine assessment and correction of biotin status may ameliorate IBD and help maintain intestinal integrity. Table 1: 3-hydroxyisovaleryl carnitine levels and biotin deficiency

Analysis of dilute protein samples is a challenging task for scientific and industrial labs all over the world. Although there are different methods available that allow for protein enrichment from various biological sources, all of them have serious limitations apart from their advantages. In order to perform highly reproducible and sensitive protein analysis of lowest concentrated samples, we optimized a method to enrich proteins on affinity beads (StrataClean) recently. This chapter describes the general protocol of this strategy, thereby discussing the power as well as the limits of this technique for qualitative and quantitative proteomic studies. Moreover, additional application and protocol variants will be discussed, expanding the number of compatible up- and downstream processing techniques compared to the originally published method. Hence, we evaluated the reduction of time for sample preparation by use of preprimed affinity beads and shorter incubation durations as well as the influence of high concentration of salts or urea in the sample buffer.

This paper reports a 6-to-18 GHz integrated phased- array receiver implemented in 130-nm CMOS. The receiver is easily scalable to build a very large-scale phased-array system. It concurrently forms four independent beams at two different frequencies from 6 to 18 GHz. The nominal conversion gain of the receiver ranges from 16 to 24 dB over the entire band while the worst-case cross-band and cross-polarization rejections are achieved 48 dB and 63 dB, respectively. Phase shifting is performed in the LO path by a digital phase rotator with the worst-case RMS phase error and amplitude variation of 0.5deg and 0.4 dB, respectively, over the entire band. A four-element phased-array receiver system is implemented based on four receiver chips. The measured array patterns agree well with the theoretical ones with a peak-to-null ratio of over 21.5 dB.

An agreement between the governments of the province of Québec and the State of Vermont calls for a 41% decrease in phosphorus (P) loads reaching Missisquoi Bay, the northern portion of Lake Champlain. The agreement particularly targets the agricultural sector, since 80% of non-point source P inputs to the bay are associated with cultivated lands. In order to identify sustainable cropping practices likely to help meet the target P loads, the SWAT (soil and water assessment tool) model was employed to assess hydrological performance, erosion processes and P mobility on the bay’s principal Québec P contributing tributary, the 630 km2 Pike River watershed. Strong in-watershed spatial clustering of vulnerability to non-point source exports highlights the need for targeted implementation of sustainable agricultural practices and soil conservation works to derive the reduction in P loads. Planting cover crops over the 10% most vulnerable lands would result in roughly a 21% d rop in overall P exports at the watershed outlet, whereas the same 10% randomly distributed over the watershed would only contribute to a 6% drop in P exports. The study of different field-scale management scenarios indicated that achieving the targeted 41% reduction in P exports would require the widespread (half the land devoted to annual crops) implementation of sustainable cropping practices, and the conversion of a specific 10% of the territory to either cover crops or permanent prairie land. Meeting the P target-loads would require additional investments in the protection of floodplains and riparian strips, the targeted construction of runoff-control structures, and the rapid soil incorporation of manures on lands dedicated to annual crops. Key words: Soil and water assessment tool, modelling, sediment, phosphorus, cropping system, scenario, best agricultural management practices

The hydrology, erosion processes and phosphorus mobility were modelled for the 630 km2 Pike River watershed, an important Quebec tributary of Lake Champlain. Given the recurring issue of cyanobacterial blooms in Missisquoi Bay, intervening to reduce the influx of phosphorus to the bay became a priority and led to an agreement between the governments of the province of Quebec and the state of Vermont. The model's parameterization was supported by a characterization and spatial representation of agricultural landscapes and production systems according to a field-scale partitioning of cultivated lands into over 2,400 hydrological response units, each distinctive in its combination of soil properties, topography, fertilizer inputs, and inclusion within one of 99 subwatersheds in the region under study. The model's calibration and validation were based on data from four hydrometric stations as well as the monitoring of water quality at the outlet of two small (six to eight km2) experimental watersheds of contr...

The Guadalentin basin, located in the SE of Spain, has a semiarid climate and presents typical characteristics of Mediterranean landscapes vulnerable to land degradation processes and desertification risks. In such an environment, when the vegetation cover is low, the signal received by satellites is dominated by the spectral properties of soils. Changes in these properties can be interpreted in terms of varying soil surface conditions. These optical changes underline the major modifications affecting soil surface under land degradation processes. The present research uses remote sensing techniques to characterise land degradation based on two approaches: spectral mixture analysis and a set of indices describing the spectrum shape. It also presents an integrated approach for evaluating ecosystem vulnerability to land degradation, through the combined analysis of spectrally-derived land units and geomorphometric units. Specific objectives consist of evaluating the potential of extending the indices describ...

This article presents a method to study and correct radiometric distortions caused by topography in SAR images. The method is easy to implement and requires neither sophisticated software nor code-level programming. It also considers the case of a flat surface having an elevation different from the one for which calibration parameters were derived. An ortho-image of the slant range distance is used with a Digital Elevation Model to generate images of the local incident angle along the range and azimuth directions. The method compensates for variations in the terrain area of each pixel and for the angular dependence of backscatter, allowing the choice of either an empirical or semi-empirical scattering model. The method is applied to high-resolution C-SAR subsets of an agricultural area in the Central Cordillera of Costa Rica. The removal of topographic features appears excellent for local incident angles up to 80, but small-scale structures have pronounced effects on the radar return for higher local incident angles and are not adequately corrected.

Cette etude porte sur l'analyse du potentiel et de l'interet du moyen infrarouge pour la detection et la cartographie des residus de cultures. Les resultats obtenus montrent que, sans contredit, le moyen infrarouge est la region spectrale qui possede la meilleure sensibilite a la presence des residus. Les indices NDI et SACRI montrent une sensibilite reduite en terme de detection des residus. Bien que l'indice NDI5-7 presente une bonne sensibilite a la variation du taux de couverture par les residus, il reste sensible aux proprietes optiques des sols nus sous-jacents, notamment lorsque le sol est sec et de couleur claire et brillante. Le MSACRI (Modified Soil Adjusted Crop Residue Index) montre un tres bon potentiel pour minimiser l'effet des sols sous-jacents et une assez bonne dynamique, avec des valeurs moyennes voisines de ± 0,03 pour les sols nus et proches de 0,20 pour des residus couvrants. L'introduction d'une constante multiplicative egale a 5 permet de resoudre le probleme de la saturation et ramene les valeurs de MSACRI dans une gamme qui varie entre 0 et 1 avec un coefficient de correlation egal a 0,97.

We evaluated the potential of a digital ground-penetrating radar (GPR) for soil moisture determination. Ground-penetrating radar offers a fast and nondestructive way for estimating the soil dielectric constant and may be an interesting tool for low-cost mapping of soil moisture. Two modes of operation were considered: (i) the ground mode where signal propagation between the antennas placed on the surface was studied; (ii) the airborne mode where the antennas are raised 5-15 m above the soil surface. Variables describing the GPR response were defined and related to the soil moisture. It is shown from field experiments that the GPR measurements performed at 200 MHz in both modes are mainly affected by the moisture in the 10- to 20-cm topsoil layer. In the ground mode, the obtained soil moisture error after calibration was lower than 0.03 m 3 /m 3 . In the airborne mode, soil moisture estimations were less accurate (0.046 m 3 /m 3 ). The wave spreading loss characterization has to be improved to get an altitude-independent GPR measurement.

Objective: The aim of this double-masked, placebo-controlled trial was to confirm the anaesthetic effect of EMLA cream compared with placebo when used for sharp debridement of venous leg ulcers and to test its feasibility with respect to the usual procedure. Methods: One hundred and ten patients with venous ulcers were randomised to EMLA or placebo cream treatment for 30-45 min. Pain from debridement was evaluated by the patient on a 100 mm visual analogue scale (VAS) and by the physician on a verbal scale. Results: The median VAS scores were 16.5 and 52 in EMLA- and placebo-treated patients, respectively (pConclusion: Debridement of venous leg ulcers using topical anaesthesia is easy and safe, with adequate pain relief in both in- and outpatients.

This paper presents a simulation comparative study of the effect of salt on the imaginary part (/spl epsiv/") of the dielectric constant (/spl epsiv/) and therefore on the backscattering coefficient (/spl sigma//sub 0/). Mixing model is adapted to estimate this effect on Soil of Wadi El-Natrun area, west desert of Egypt, as a representative area of salt affected soils in the arid zone. Small perturbation backscattering coefficient model (SPM) is also used to estimate the best mode of RADARSAT-1. S1 and S3 were found to be the best choice to detect such type of soil for this area and similar one.

Spatial modelling of hydrological and erosion processes at watershed scale is subject to an increasing development simultaneously with the expanded use of remote sensing and geographical information systems (GIS). Nevertheless, the raster structure of available spatial erosion models does not take into account some human landscape dimensions. Linear and directional features are commonly neglected in water and sediment transport modelling. This paper presents an attempt for integrating influences of spatial pattern discontinuities and directivity effects due to tillage and row of plants on the distribution of flows in agricultural watersheds. Introduction of these improvements in the ANSWERS (Areal Nonpoint Source Watershed Environment Response Simulation) model are in process.

A highly integrated single chip 3 volt GaAs transceiver MMIC has been developed for wireless local area networks (WLAN). The multi-function chip includes a low noise amplifier (LNA), down mixer, diversity switching, transmit-receive (Tx/Rx) switching and a power amplifier (PA). The chip was fabricated based on a 3 volt GaAs MESFET implant process which was optimized for the multiple sub-circuits. The transceiver MMIC achieved excellent performance over the 2.45 GHz Industrial, Scientific and Medical (ISM) frequency band. This multi-function IC is packaged in a low cost ceramic package to meet cost goals for the commercial market. The fabricated circuits have achieved excellent performance. Typical circuits achieve 19.5 dB small signal conversion gain (antenna to mixer output) and 6 dB noise figure while consuming 12 mA with a 3 volt supply. The mixer and LNA include CMOS compatible enable/disable circuitry to conserve current during standby operation. In the transmit mode, the transceiver MMIC provides an output power of 22 dBm with greater than 50% efficiency. In addition, power control circuitry is included within the power amplifier to provide an adjustable output power and has pulse shaping circuitry to minimize spectral splatter under pulsed bias operation levels.

A low noise amplifier for Global Positioning System (GPS) applications has been designed and tested with good results. The amplifier can operate from 2-5 V with 1.0 dB NF and 18.4 dB of gain at 5 V and 6.5 mA. The device is packaged in a low cost 8 lead SOIC and features a DC coupled RF output for remote antenna applications.

The authors present a new index for mapping and estimating the crop residue cover fraction: the MSACRI (Modified Soil Adjusted Crop Residue Index). This index exploits the mid infrared channels: 1.55 /spl mu/m to 1.75 /spl mu/m and 2.10 /spl mu/m to 2.35 /spl mu/m. Compared to the visible, these channels are characterized by large transparence in relation to atmospheric constituents. In extreme atmospheric conditions, the MSACRI is subject to a slight reduction of approximately 4%. It offers better discrimination of soils/residue and shows quite good dynamics in the presence of residue with average values close to /spl plusmn/0.03 for bare soil and close to 0.70 for full cover residue.

A study was conducted in 1996 and 1997 to develop a model that would simulate radar backscatter in histosols with different field managements. Measurements were made under various soil moisture content using the Canadian Remote Sensing Centre scatterometer. Seedbed and harrow in 1996, and harrow, moldboard and chisel treatments in 1997, were applied to plots with rows oriented parallel and perpendicular to the view angle of the antennas. The scatterometer operated in two bands (C, L), four polarisations (HH, HV, VH, VV) and four incidence angles (25/spl deg/, 30/spl deg/, 40/spl deg/, 50/spl deg/). This paper presents the methodology, the models and some results from 1996 data analysis. Actual models were not adequate to simulate the backscatter in seedbed plots except at some combinations of incidence angle and polarisation. They were not able to simulate the angular response of the signal when rows were perpendicular to view angle. Calibration and further development is on-going with 1997 data.

L'emission micro-onde d'une surface partiellement recouverte de vegetation est influencee par la teneur en eau de la surface du sol (θ s ), la vegetation et le mode de repartition spatial de la vegetation au sein de la surface de mesure. L'etude de ce dernier facteur, peu etudie jusqu'a present, constitue l'objet principal de cet article. Un modele simple d'emission micro-onde par une surface couverte de vegetation est utilise dans cette etude afin d'interpreter les mesures radiometriques et les inverser pour estimer θ s . Les donnees experimentales ont ete acquises a 1,4 GHz, 5,05 GHz et 10,65 GHz en milieu controle sur des cultures de sorgho et de ble presentant une couverture spatiale partielle et heterogene. L'analyse a porte dans un premier temps sur les parametres de vegetation et de rugosite. Nous nous sommes ensuite interesses aux variables du modele micro-onde qui sont: le contenu en eau de la vegetation (w c ) et θ s . Nous montrons qu'a 10.65 GHz, l'indice de polarisation definit par PDh=(T BV -T BH ) * T BH (ou T Bp est la temperature de brillance micro-onde en polarisation p: horizontale ou verticale) permet d'estimer W c selon une relation unique pour le sorgho et le ble et ceci independamment du mode de repartition spatiale de la vegetation qui etait dans notre etude soit eparse, soit sous forme de tache. L'estimation de θ s en inversant le modele d'emission micro-onde a ete testee. L'inversion a ete realisee en combinant les mesures a 1,4 ou 5,05 GHz et celles a 10,65 GHz. Nous avons obtenu des estimations satisfaisantes sur les estimations de θ s lorsque les parametres du modele sont connus.

In the field of remote sensing applications, scientists have developed vegetation indices (VI) for qualitatively and quantitatively evaluating vegetative covers using spectral measurements. The spectral response of vegetated areas presents a complex mixture of vegetation, soil brightness, environmental effects, shadow, soil color and moisture. Moreover, the VI is affected by spatial‐temporal variations of the atmosphere. Over forty vegetation indices have been developed during the last two decades in order to enhance vegetation response and minimize the effects of the factors described above. This paper summarizes, refers and discusses most of the vegetation indices found in the literature. It presents different existing classifications of indices and proposes to group them in a new classification.

The objective of this study was to evaluate the incidence of morbidity (at least one hospitalization) during the first twelve months of hemodialysis (thrice weekly for 4 hours) in 54 (27 males and 27 females) sex and age matched patients, of whom 32 were treated with AN 69 (M/F = 13/19, 62 +/- 14 years) and 22 with Cuprophan (M/F = 14/8, 61 +/- 14 years). Patients were classified according to the value of TAC urea during the period under study: constantly superior or equal to 20 mmol/liter in Group A (high TAC urea) or inferior to 20 mmol/liter in Group B (low TAC urea). Dialysis quantification (Kt/V) and estimation of the patient's protein catabolic rate (PCR) were based on measurement of the midweek pre- and post-dialysis blood urea nitrogen. In the patients of Group B, incidence of morbidity was significantly increased when age was over 50 years and when AN 69 membrane was used (P0.02). Furthermore, in Group A, the risk of hospitalization was significantly higher in patients treated by Cuprophan than in those treated by AN 69 (P0.02). The survival rate was also studied. Better survival (70%) at four years was observed in patients with high TAC urea who were treated by AN 69. The difference was highly significant with the survival rate (22%) in patients with high TAC urea who were treated by Cuprophan (P0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

The combined effects of topography, slope, look angle, and aspect on C-band synthetic-aperture radar (SAR) data on the radiometric quality of SAR images in a region of moderate relief are examined. A correction method was used to attenuate the change of illumination across the swath due to the antenna pattern. Ground data were integrated into the analysis using a digital terrain model (DTM). Correction functions based on the cosine of the incidence angle were applied to the thematic classes and to the grouped classes in order to reduce the effects related to topography. It was found that it is possible to eliminate part of the radiometric variations created by moderate topographic relief. After the corrections were applied, a reduction was noted of the variance in the radiometric values of the spectral signatures of the cover types, which ranged between 3.03% and 9.47%, depending on the correction function used. >

Two airborne surveys, simulating the spectral and spatial resolution of the Thematic Mapper sensor of Landsat-5 were made during the summer of 1982 (10 June and 18 Aug.). The Agriculture Canada Research Station at Lennoxville was surveyed and two common field crops in Quebec were studied. The digital image analysis revealed two parameters which influence the spectral signatures of the vegetation: the alfalfa plots presented spectral variations relative to cover structure which were associated with growth stage, and the corn plot analysis suggests a relation between the drainage conditions of the soil and growth characteristics.Key words: Remote sensing, airborne surveys, Thematic Mapper simulation, field crops, digital image analysis, spectral and multidate analysis

33 patients with chronic renal failure were divided into two groups. Group I consisted of 8 non-dialysed patients without any clinical or biochemical sign of liver disturbance nor any iron supplementation. Group II consisted of 25 maintenance hemodialysis (MHD) patients treated from 2 to 13 years. 19 subjects had chronic B hepatitis. Total exogenous iron load parenteral iron and/or blood transfusions) was calculated. Body iron overload (hemosiderosis) was assessed by liver iron concentration (LIC) in needle biopsy specimens according to Barry's method (less than 200 microgram/100 mg dry weight) and serum ferritin levels (less than 360 ng/ml). 4 patients whose serum ferritin was increased with or without hepatic fibrosis and with or without any organ dysfunction due to hemochromatosis received i.v. infusions of desferrioxamine in doses of 2 g at each dialysis. Serum ferritin levels were correlated with LIC (p less than 0.001) and iron load (p less than 0.001). Hemosiderosis was noted in 16 MHD patients (group II) and correlated with iron load. Hemochromatosis was noted in 4 patients (group II). 4 hemodialysed patients with iron overload were treated by desferrioxamine from 6 to 18 months. During this therapy, body iron stores fell and organ dysfunction (heart failure, hepatic cytolysis, anaemia, diabetes mellitus improved. Long-term chelation therapy by desferrioxamine was effective and the chelated iron was readily removed by dialysis. These data show the importance of precise evaluation of iron stores in MHD patients.

En niai 1996, un projet fut mene dans la region de Sherrington et Ste-Clotilde (Quebec) afin de determiner le potentiel des capteurs hyperfrequences, visible et proche infrarouge pour estimer la variation des teneurs en eau dans les histosols au printemps. Des donnees hyperfrequences aeroportees furent acquises avec un radiometre SLF MR (Scanning Low Frequency Microwave Radiometerj. Des images furent prises dans le visible et proche infrarouge avec un spectrometre imageur CASI (Compact Airborne Spectrographic Imager) monte en parallele avec le radiometre. Une image RADARSAT a haute resolution fut aussi acquise. Les donnees d'humidite du sol et des informations complementaires furent prises dans vingt champs pendant le survol (26 mai 96) et le passage de RADARSAT (30 mai 96). Les resultats preliminaires ont montre que les champs pouvaient etre discrimines selon qu'ils sont nus ou avec cultures/residus en utilisant les spectres de reflectance du CASI. Dans les sols nus. les valeurs de reflectance ont augmente avec la diminution des teneurs en eau. La relation entre la reflectance dans le proche infrarouge (850 ou 870nm) et la teneur en eau etait bien ajustee par une fonction polynomiale du second ordre. Les indices de vegetation (NDVI) calcules au-dessus de champs de cereales etaient correles avec la densite du couvert (gamme 10-25%). Les temperatures de brillance ont presente une relation lineaire avec les teneurs en eau a la surface. Cette relation etait independante de la rugosite et de la presence ou non de cereales. Cependant, la relation entre les coefficients de retrodiffusion de RADARSAT et les teneurs en eau etait dependante de ces deux parametres. Les champs nus lisses (semes en planches) presentaient des valeurs de retrodiffusion plus faibles. Il fut donc possible de distinguer les champs nus lisses des autres champs.

Le potentiel des capteurs actifs a hyperfrequences, et plus particulierement RADARSAT, pour des applications en sols organiques a ete evalue a l'aide d'un diffusiometre monte sur un camion. Les objectifs de l'etude etaient de modeliser la relation entre la teneur en eau du sol, la constante dielectrique et le signal radar et d'evaluer l'impact de la culture et des pratiques culturales sur le signal, Une collecte hebdomadaire de donnees fut menee sur un sol organique a la ferme experimentale de Ste-Clotilde (Quebec) entre juin et septembre 1996. Les resultats obtenus ont montre que le suivi des teneurs en eau devait se faire de preference aux faibles angles d'incidence (25°-HH, 30°-VV) en l'absence de vegetation. Par contre, l'estimation de la biomasse, de la teneur en eau dans la plante et de la hauteur du couvert etait preferable aux grands angles d'incidence (50°). Le moment et le type de pratiques culturales ont eu un effet sur le comportement angulaire du signal et par consequent l'estimation de la teneur en eau. Une relation lineaire entre le signal et la constante dielectrique a ete derivee pour une surface hersee et une surface semee; elle a montre que la rugosite avait influence surtout aux plus fortes teneurs en eau. L'orientation perpendiculaire des sillons par rapport a la visee du capteur dans un champ herse a produit un accroissement du signal en bande L a tous les angles. Le signal en bande C a ete plus fortement correle avec la hauteur des plants et la biomasse seche qu'avec l'humidite des plants; on a observe l'inverse en bande L. La biomasse seche a pu etre estimee par le signal CHH. L'ajout de la hauteur du couvert dans le modele de regression a permis d'expliquer 85% de la variation de la biomasse seche a 50° d'angle d'incidence. Les correlations entre les parametres de la vegetation et le signal etaient plus elevees en bande L qu'en bande C.

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