Protein Losses and Urea Nitrogen Underestimate Total Nitrogen Losses in Peritoneal Dialysis and Hemodialysis Patients

Objective: Muscle wasting is associated with increased mortality and is commonly reported in dialysis patients. Hemodialysis (HD) and peritoneal dialysis (PD) treatments lead to protein losses in effluent dialysate. We wished to determine whether changes in current dialysis practice had increased therapy-associated nitrogen losses. / Design: Cross-sectional cohort study. / Methods: Measurement of total protein, urea and total nitrogen in effluent dialysate from 24-hour collections from PD patients, and during haemodiafiltration (HDF) and haemodialysis (HD) sessions. / Subjects: One hundred eight adult dialysis patients. / Intervention: Peritoneal dialysis, high-flux haemodialysis and haemodiafiltration. / Main Outcome Measure: Total nitrogen and protein losses. / Results: Dialysate protein losses were measured in 68 PD and 40 HD patients. Sessional losses of urea (13.9 [9.2-21.1] vs. 4.8 [2.8-7.8] g); protein (8.6 [7.2-11.1] vs. 6.7 [3.9-11.1] g); and nitrogen (11.5 [8.7-17.7] vs. 4.9 [2.6-9.5] g) were all greater for HD than PD, P < .001. Protein-derived nitrogen was 71.9 (54.4-110.4) g for HD and 30.8 (16.1-59.6) g for PD. Weekly protein losses were lower with HD 25.9 (21.5-33.4) versus 46.6 (27-77.6) g/week, but nitrogen losses were similar. We found no difference between high-flux HD and HDF: urea (13.5 [8.8-20.6] vs. 15.3 [10.5-25.5] g); protein (8.8 [7.3-12.2] vs. 7.6 [5.8-9.0] g); and total nitrogen (11.6 [8.3-17.3] vs. 10.8 [8.9-22.5] g). Urea nitrogen (UN) only accounted for 45.1 (38.3-51.0)% PD and 63.0 (55.3-62.4)% HD of total nitrogen losses. / Conclusion: Although sessional losses of protein and UN were greater with HD, weekly losses were similar between modalities. We found no differences between HD and HDF. However, total nitrogen losses were much greater than the combination of protein and UN, suggesting greater nutritional losses with dialysis than previously reported

The effect of reverse current on the dark properties of photovoltaic solar modules

AbstractForward and reverse dark current-voltage (I-V) and capacitance-voltage (C-V) characteristics of commercial amorphous silicon solar modules, were measured in order to study their performance under the influence of induced reverse currents. Maximum module surface temperatures were directly related to each value of the induced reverse current and in to the amount of current leakage respectively. Microscopic changes as a result of hot spots defects and overheating of the solar module, linked to reverse current effects, were also documented and discussed. Experimental evidence showed that different levels of reverse currents are confirmed to be a major degrading factor affecting the performance, efficiency, and power of solar modules

Determinación de hormonas esteroides en heces de borrego cimarrón (Ovis canadensis Shaw) silvestres en Baja California, México

Objective: Determination of steroids hormones in wild bighorn sheep feces with a non-invasive method. Design/methodology/approach: In this study we analyze progestogens, androgens and estradiol, concentrations in wild bighorn sheep feces of Sierra San Felipe in Baja California during Spring, Winter and Summer seasons of the year 2007. Steroids were quantified by enzime immunoassay and evaluated using a micro titer plate. Results: With the hormonal profile it was identified that 96 feces were from males and 65 from females. The concentration of progestogens in the feces identified as females varied among the seasons of the year with spring being the highest concentration (280 ng/gr). Progestogen and estrogen concentrations in females increased as environmental conditions improved from winter to spring, coinciding with male androgen increase of 23.78 ng/gr. Limitations on study/implications: With this method it was not possible to assign the sex of samples that were identified as coming from juvenile individuals. We recommended to analyze fresh feces samples to relate the hormone concentrations with seasonal reproductive events. Findings/conclusions: The increase in progestogen and estrogen concentrations in feces of females and androgens in males during the spring suggests the initiation of reproductive activity. The concentrations of these hormones in both sexes during the summer are very low (&lt;5 ng/gr), which suggests low reproductive activityObjetivo: Determinación de hormonas esteroides en heces de borrego cimarrón silvestre mediante un método no invasivo. Diseño / metodología / enfoque: En este estudio se detectaron progestágenos, andrógenos y estradiol en heces de borrego cimarrón silvestres que habitan en la Sierra San Felipe en Baja California, durante la primavera, invierno y verano del año 2007. Los esteroides se cuantificaron mediante inmunoensayo enzimático y la cuantificación se realizó en una placa de micro titulación. Resultados: Con el perfil hormonal se identificó que 96 eran heces provenientes de machos y 65 de hembras. La concentración de progestágenos en las heces identificadas como hembras varió entre las estaciones del año siendo la primavera con la concentración más alta (280 ng/gr). Las concentraciones de progestágenos y estrógenos en las hembras aumentaron a medida que las condiciones ambientales mejoraron desde el invierno hasta la primavera, coincidiendo con el aumento de andrógenos en los machos de 23.78 ng / gr. Limitaciones en el estudio / implicaciones: con este método no fue posible asignar el sexo de las muestras que se identificaron que provienen de individuos juveniles. Se recomienda analizar muestras de heces frescas para relacionar las concentraciones de hormonas con eventos reproductivos estacionales. Hallazgos / conclusiones: El aumento de las concentraciones de progestágenos y estrógenos en las heces de las hembras y los andrógenos en los machos en la primavera sugiere el inicio de la actividad reproductiva. Las concentraciones de estas hormonas en ambos sexos durante el verano son muy bajas (&lt;5 ng / gr), lo que sugiere una actividad reproductiva baja. &nbsp

Short-Term Memory Maintenance of Object Locations during Active Navigation: Which Working Memory Subsystem Is Essential?

The goal of the present study was to examine the extent to which working memory supports the maintenance of object locations during active spatial navigation. Participants were required to navigate a virtual environment and to encode the location of a target object. In the subsequent maintenance period they performed one of three secondary tasks that were designed to selectively load visual, verbal or spatial working memory subsystems. Thereafter participants re-entered the environment and navigated back to the remembered location of the target. We found that while navigation performance in participants with high navigational ability was impaired only by the spatial secondary task, navigation performance in participants with poor navigational ability was impaired equally by spatial and verbal secondary tasks. The visual secondary task had no effect on navigation performance. Our results extend current knowledge by showing that the differential engagement of working memory subsystems is determined by navigational ability

Visuospatial working memory in children and adolescents with 22q11.2 deletion syndrome; an fMRI study

22q11.2 deletion syndrome (22q11DS) is a genetic disorder associated with a microdeletion of chromosome 22q11. In addition to high rates of neuropsychiatric disorders such as schizophrenia and attention deficit hyperactivity disorder, children with 22q11DS have a specific neuropsychological profile with particular deficits in visuospatial and working memory. However, the neurobiological substrate underlying these deficits is poorly understood. We investigated brain function during a visuospatial working memory (SWM) task in eight children with 22q11DS and 13 healthy controls, using fMRI. Both groups showed task-related activation in dorsolateral prefrontal cortex (DLPFC) and bilateral parietal association cortices. Controls activated parietal and occipital regions significantly more than those with 22q11DS but there was no significant between-group difference in DLPFC. In addition, while controls had a significant age-related increase in the activation of posterior brain regions and an age-related decrease in anterior regions, the 22q11DS children showed the opposite pattern. Genetically determined differences in the development of specific brain systems may underpin the cognitive deficits in 22q11DS, and may contribute to the later development of neuropsychiatric disorders

Progress and Research Needs of Plant Biomass Degradation by Basidiomycete Fungi

Peer reviewe

Trials

BACKGROUND: Postoperative upper gastrointestinal fistula (PUGIF) is a devastating complication, leading to high mortality (reaching up to 80%), increased length of hospital stay, reduced health-related quality of life and increased health costs. Nutritional support is a key component of therapy in such cases, which is related to the high prevalence of malnutrition. In the prophylactic setting, enteral nutrition (EN) is associated with a shorter hospital stay, a lower incidence of severe infectious complications, lower severity of complications and decreased cost compared to total parenteral nutrition (TPN) following major upper gastrointestinal (GI) surgery. There is little evidence available for the curative setting after fistula occurrence. We hypothesize that EN increases the 30-day fistula closure rate in PUGIF, allowing better health-related quality of life without increasing the morbidity or mortality. METHODS/DESIGN: The NUTRILEAK trial is a multicenter, randomized, parallel-group, open-label phase III trial to assess the efficacy of EN (the experimental group) compared with TPN (the control group) in patients with PUGIF. The primary objective of the study is to compare EN versus TPN in the treatment of PUGIF (after esophagogastric resection including bariatric surgery, duodenojejunal resection or pancreatic resection with digestive tract violation) in terms of the 30-day fistula closure rate. Secondary objectives are to evaluate the 6-month postrandomization fistula closure rate, time of first fistula closure (in days), the medical- and surgical treatment-related complication rate at 6 months after randomization, the fistula-related complication rate at 6 months after randomization, the type and severity of early (30 days after randomization) and late fistula-related complications (over 30 days after randomization), 30-day and 6-month postrandomization mortality rate, nutritional status at day 30, day 60, day 90 and day 180 postrandomization, the mean length of hospital stay, the patient's health-related quality of life (by self-assessment questionnaire), oral feeding time and direct costs of treatment. A total of 321 patients will be enrolled. DISCUSSION: The two nutritional supports are already used in daily practice, but most surgeons are reluctant to use the enteral route in case of PUGIF. This study will be the first randomized trial testing the role of EN versus TPN in PUGIF. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03742752. Registered on 14 November 2018.This research program is funded by the French Ministry of Health through Programme Hospitalier de Recherche Clinique 2016

From short-term store to multicomponent working memory: The role of the modal model

The term “modal model” reflects the importance of Atkinson and Shiffrin’s paper in capturing the major developments in the cognitive psychology of memory that were achieved over the previous decade, providing an integrated framework that has formed the basis for many future developments. The fact that it is still the most cited model from that period some 50 years later has, we suggest, implications for the model itself and for theorising in psychology more generally. We review the essential foundations of the model before going on to discuss briefly the way in which one of its components, the short-term store, had influenced our own concept of a multicomponent working memory. This is followed by a discussion of recent claims that the concept of a short-term store be replaced by an interpretation in terms of activated long-term memory. We present several reasons to question these proposals. We conclude with a brief discussion of the implications of the longevity of the modal model for styles of theorising in cognitive psychology

Etude d'un moteur à réluctance variable à disques imbriqués alimenté à tension constante

Dans cet article, nous présentons une étude théorique et expérimentale d'un moteur à réluctance variable à disques imbriqués alimenté directement à 50 Hz par un réseau triphasé industriel à tension efficace constante. Les deux principales hypothèses faites dans ce travail sont les suivantes : les circuits magnétiques de la machine à réluctance variable sont non saturés et la ligne d'arbre entraînée est supposée infiniment rigide. Dans ce cadre, nous présentons les caractéristiques des divers fonctionnements synchrones possibles ainsi que leurs conditions de stabilité