Normal Pool Research Articles

The Power Function for Representing the Reservoir Rating Curve: Morphological Meaning and Suitability for Dam Breach Modelling

In this paper the authors demonstrate that the simple power function gives a good description of the reservoir morphology. This function proved to be suitable for application on 97 reservoirs taken from three different geographical regions in the world. The power function is suitable to obtain an accurate fitting of the reservoir rating curve using a very limited number of surveyed elevations and volumes or areas. In particular it is shown that two points are enough for a good fitting of the curve, or even only one if volume and surface for an elevation close to normal or maximum pool are both available. The results obtained for dam breach calculations using this equation, have the same quality of those achieved using the elevation-volume table. The paper stresses that the exponent of power equation can be expressed by a formula which has a precise morphological meaning, as it represents the ratio between the volume which the reservoir would have if it were a cylinder with its base area and height equal to the respective maximum values of the actual reservoir, and the real volume of the reservoir.

Abstract 3336: ST6Gal-I glycosyltransferase promotes an undifferentiated cell phenotype and enhances c-kit signaling

Abstract Acute myelogenous leukemia (AML) is characterized by an increased number of myeloid cells in the bone marrow. These cells are arrested in their maturation process, frequently resulting in hematopoietic insufficiency. Recent advancements in molecular genetics have identified new markers that may be useful in diagnosing AML, including mutant c-kit (CD117). c-kit is a receptor tyrosine kinase and activating mutations in this receptor have been identified as a functional driver of AML and other myeloproliferative diseases. c-kit also plays a major role in maintaining normal stem cell pools. Prior studies suggest that ST6Gal-I, a unique glycosyltransferase upregulated in many cancers, promotes a stem-like cell phenotype in epithelial tumor cells. ST6Gal-I is a sialyltransferase that adds a negatively charged sialic acid in an α2-6 linkage to membrane glycoproteins. In this study, we show c-kit to be a substrate of ST6Gal-I, with increased sialylation correlating to increased c-kit activation. In order to study the effects of sialylation on signaling, we forced constitutive expression of ST6Gal-I in the U937 monocytic leukemia cell line. c-kit signaling was then induced by treating U937 cells with stem cell factor (SCF), the c-kit ligand. Here we show enhanced SCF-mediated c-kit activation, indicated by increased levels of phospho-c-kit in ST6Gal-I overexpressing cells. This, in turn, is associated with increased activation of downstream effecters of c-kit signaling, phospho-Erk and phospho-Akt. We further hypothesize that ST6Gal-I might play a role in the cell differentiation process. To test the effects of sialylation on differentiation, we used a well-established model to induce monocyte cell differentiation, treatment with the phorbol ester, PMA. PMA is known to induce macrophage differentiation in U937 cells, evidenced by exit from the cell cycle and upregulation of differentiation markers, including CD11b. Macrophage differentiation induces downregulation of endogenous ST6Gal-I, thereby reducing surface sialylation of specific receptors. However, forced overexpression of ST6Gal-I inhibits PMA-induced exit from the cell cycle, suggesting that ST6Gal-I acts to maintain cells in an undifferentiated state. To further understand the effects of receptor sialylation on PMA-induced differentiation, we used flow cytometric analysis to evaluate surface markers on U937 cells with or without ST6Gal-I overexpression. We show that forced expression of ST6Gal-I inhibits PMA-induced upregulation of CD11b, whereas c-kit expression is elevated in ST6Gal-I overexpressing cells relative to parental cells. These results suggest a novel mechanism by which ST6Gal-I contributes to an undifferentiated state in part through the regulation of the c-kit receptor. Citation Format: Kaitlyn A. Dorsett, Susan L. Bellis. ST6Gal-I glycosyltransferase promotes an undifferentiated cell phenotype and enhances c-kit signaling. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3336.

171. Quantification of Human FVIII and Estimation of Its Molecular Weight: Potential Applications in Gene Therapy for Hemophilia A

Current protocols for measurement of FVIII rely on chromogenic or coagulation assays, and are not designed for quantification of FVIII antigen. Development of assays for measuring FVIII antigen may be necessary and beneficial for determining the efficiency of newer therapeutic approaches for Hemophilia A such as gene therapy. Herein, we describe the development of proprietary assays for quantification of human FVIII in plasma matrices from heterologous species, and estimation of the human FVIII molecular weight.A variety of monoclonal antibodies against the FVIII heavy and light chain were screened for their ability to recognize human FVIII from normal human plasma pool, or CHO cell derived recombinant human FVIII-B domain deleted (FVIII-BDD) spiked in mouse and non-human primate (NHP) plasma. Based on the initial screen, a monoclonal each against the human FVIII heavy or the light chain was selected for enrichment, followed by detection using a sheep anti-FVIII polyclonal antibody. Using this sandwich ELISA procedure, a standard curve was generated for human FVIII-BDD antigen in the range of 100 ng/ml - 0.1 ng/ml, and minimal cross reactivity was observed when tested with mouse and NHP plasma pools containing endogenous FVIII antigen. Furthermore, individual mouse strain plasma pools, and individual NHP samples representing different genetic origins were also screened for cross-reactivity to endogenous FVIII antigen and found to be negative. The sandwich ELISA was used to quantify FVIII antigen in defined plasma samples from normal or Hemophilia A human subjects, and antigen levels correlated with the reported FVIII activity.The ELISA procedure was modified and adapted for estimation of the human FVIII antigen molecular weight. FVIII heavy and light chains, from normal human plasma pool or recombinant human FVIII-B domain deleted (FVIII-BDD), were enriched followed by resolution using a denaturing reducing PAGE and western blotting. The apparent migration of heavy and light chain was at the appropriate molecular weights; 90-185 kDa for heavy chain and 70 kDa for light chain. In case of heavy chain from normal human plasma pool, a ladder of differing molecular weights was seen and may be indicative of the differential furin and thrombin dependent processing of the B-domain.Thus, these newly developed assays for quantification of human FVIII and estimation of its molecular weights will be useful for further characterization of gene therapy for Hemophilia A.

Partial Nucleate Pool Boiling at Low Heat Flux: Preliminary Ground Test for SOBER-SJ10

Focusing on partial nucleate pool boiling at low heat flux, SOBER-SJ10, one of 27 experiments of the program SJ-10, has been proposed to study local convection and heat transfer around an isolated growing vapor bubble during nucleate pool boiling on a well characterized flat surface in microgravity. An integrated micro heater has been developed. By using a local pulse overheating method in the experimental mode of single bubble boiling, a bubble nucleus can be excited with accurate spatial and temporal positioning on the top-side of a quartz glass substrate with a thickness of 2 mm and an effective heating area of 4.5 mm in diameter, and then grows under an approximate constant heat input provided by the main heater on the back-side of the substrate. Ten thin film micro-RTDs are used for local temperature measurements on the heating surface underneath the growing bubble. Normal pool boiling experiments can also be carried out with step-by-step increase of heating voltage. A series of ground test of the flight module of SOBER-SJ10 have been conducted. Good agreement of the measured data of single phase natural convection with the common-used empirical correlation warrants reasonable confidence in the data. It is found that the values of the incipience superheat of pool boiling at different subcooling are consistent with each others, verifying that the influence of subcooling on boiling incipience can be neglected. Pool boiling curves are also obtained, which shows great influence of subcooling on heat transfer of partial nucleate pool boiling, particularly in lower heat flux.

Evaluating Blind Image Quality Using RBF Neural Network

Blind Image Quality Assessment (BIQA) methods are the most part feeling mindful. The BIQA method learns regression models from preparing images with human subjective scores to predict the perceptual nature of test images. The general quality of image and the nature of every image patches are measured by normal pooling. By coordinating the components of normal picture measurements got from different signs, we take a multivariate Gaussian model of picture patches from an accumulation of unblemished regular pictures. The proposed radial bias function neural network method is used to evaluate the quality of images and this method represents the structure of picture distortions with flexibility.

Evaluating Blind Image Quality Using RBF Neural Network


 
 
 Blind Image Quality Assessment (BIQA) methods are the most part feeling mindful. The BIQA method learns regression models from preparing images with human subjective scores to predict the perceptual nature of test images. The general quality of image and the nature of every image patches are measured by normal pooling. By coordinating the components of normal picture measurements got from different signs, we take a multivariate Gaussian model of picture patches from an accumulation of unblemished regular pictures. The proposed radial bias function neural network method is used to evaluate the quality of images and this method represents the structure of picture distortions with flexibility.
 
 

Extreme dNTP pool changes and hypermutability in dcd ndk strains

Cells lacking deoxycytidine deaminase (DCD) have been shown to have imbalances in the normal dNTP pools that lead to multiple phenotypes, including increased mutagenesis, increased sensitivity to oxidizing agents, and to a number of antibiotics. In particular, there is an increased dCTP pool, often accompanied by a decreased dTTP pool. In the work presented here, we show that double mutants of Escherichia coli lacking both DCD and NDK (nucleoside diphosphate kinase) have even more extreme imbalances of dNTPs than mutants lacking only one or the other of these enzymes. In particular, the dCTP pool rises to very high levels, exceeding even the cellular ATP level by several-fold. This increased level of dCTP, coupled with more modest changes in other dNTPs, results in exceptionally high mutation levels. The high mutation levels are attenuated by the addition of thymidine. The results corroborate the critical importance of controlling DNA precursor levels for promoting genome stability. We also show that the addition of certain exogenous nucleosides can influence replication errors in DCD-proficient strains that are deficient in mismatch repair.

Stability analysis and treatment of a reservoir landslide under impounding conditions: a case study

The Muchanghe landslide is located on the left bank of the Muchang River in Dongping reservoir, Hubei Province, China. During reservoir impoundment, cracking and dislocation deformations occurred at the front and middle parts of the Muchanghe landslide. Once the landslide was triggered, the river could be blocked, which would lead to a serious threat to upstream flood control safety. In this study, the engineering geological properties and deformation characteristics of the Muchanghe landslide during impoundment were analyzed. A 3-D limit equilibrium method was proposed for the stability analysis of this asymmetric landslide. Based on the proposed 3-D method, a visualization program (JSlope3D) was developed and applied to evaluate the stability of the Muchanghe landslide. The results indicated that the stability of the landslide gradually decreases with the rise of impounding water level in the Dongping reservoir. When the impounding water level reaches an elevation of 490 m (normal pool level), the calculated factor of safety predicted that the landslide would be in an unstable state. To prevent the generation of a landslide failure, a reinforcement scheme involving the cutting back of the slope and backfill was proposed to improve the stability of the landslide. Using the proposed 3-D method, the Muchanghe landslide, after stabilization, was stable at different impoundment water levels and can satisfy the requirements of the design specification.

Leptin and Adiponectin Modulate the Self-renewal of Normal Human Breast Epithelial Stem Cells.

Multiple mechanisms are likely to account for the link between obesity and increased risk of postmenopausal breast cancer. Two adipokines, leptin and adiponectin, are of particular interest due to their opposing biologic functions and associations with breast cancer risk. In the current study, we investigated the effects of leptin and adiponectin on normal breast epithelial stem cells. Levels of leptin in human adipose explant-derived conditioned media positively correlated with the size of the normal breast stem cell pool. In contrast, an inverse relationship was found for adiponectin. Moreover, a strong linear relationship was observed between the leptin/adiponectin ratio in adipose conditioned media and breast stem cell self-renewal. Consistent with these findings, exogenous leptin stimulated whereas adiponectin suppressed breast stem cell self-renewal. In addition to local in-breast effects, circulating factors, including leptin and adiponectin, may contribute to the link between obesity and breast cancer. Increased levels of leptin and reduced amounts of adiponectin were found in serum from obese compared with age-matched lean postmenopausal women. Interestingly, serum from obese women increased stem cell self-renewal by 30% compared with only 7% for lean control serum. Taken together, these data suggest a plausible explanation for the obesity-driven increase in postmenopausal breast cancer risk. Leptin and adiponectin may function as both endocrine and paracrine/juxtacrine factors to modulate the size of the normal stem cell pool. Interventions that disrupt this axis and thereby normalize breast stem cell self-renewal could reduce the risk of breast cancer.

Persistent Requirement and Alteration of the Key Targets of PRDM1 During Primordial Germ Cell Development in Mice.

Primordial germ cells (PGCs) are the foundation of totipotency and vital for reproduction and heredity. PGCs in mice arise from the epiblast around Embryonic Day (E) 7.0, migrate through the hindgut endoderm, and colonize and proliferate in the embryonic gonads until around E13.5 prior to their differentiation either into prospermatogonia or oogonia. PRDM1, a transcriptional repressor, plays an essential role in PGC specification that includes robustly repressing a somatic mesodermal program. Using an inducible conditional knockout system, we show here that PRDM1 is critically required throughout PGC development. When Prdm1 was deleted in migrating PGCs at E9.5 or E10.5, or in male gonadal PGCs at E11.5, PGCs were eliminated by apoptosis from around E10.5, E11.5, or E13.5, respectively. When Prdm1 was deleted in female gonadal PGCs at E11.5, PGCs progressed into the first meiotic prophase in an apparently normal fashion, but the oogonia exhibited an aberrant pachytene phenotype, undergoing abrupt apoptosis from around E16.5. The escape of a fraction of PGCs (∼10%) from the Prdm1 deletion was sufficient to recover fairly normal germ cell pools, both in male and female adults. The key targets of PRDM1 in migrating and/or gonadal PGCs, including genes for development, apoptosis, and prospermatogonial differentiation, showed only a modest overlap with those upon PGC specification, and were enriched with histone H3 lysine 27 trimethylation (H3K27me3). Our findings provide critical insight into the mechanism for maintaining the transcriptional integrity of PGCs.

Fibrin clot structure in patients with congenital dysfibrinogenaemia

The clinical phenotype of patients with congenital dysfibrinogenaemia is highly heterogeneous, from absence of symptoms to mild bleeding, or thrombosis. A few mutations are associated with a specific phenotype, but generally the clinical course is not predictable. We investigated whether fibrin clot properties are correlated with the patient's phenotype and/or genotype. Ex vivo plasma fibrin clot characteristics, including turbidity, fibrinolysis, clot permeability and fibrin fibre density assessed by laser scanner confocal microscopy were investigated in 24 genotyped patients with congenital dysfibrinogenaemia compared to normal pool plasma. Compared to normal pool plasma, the patients were characterised by slower fibrin polymerisation (lag time, 345.10±22.98 vs. 166.00s), thinner fibrin fibres (maximum absorbance, 0.15±0.01 vs. 0.31), prolonged clot lysis time (23.72±0.97 vs. 20.32min) and larger clot pore size (21.5×10−9±4.48×10−9 vs. 7.96×10−9cm2). Laser scanning confocal microscopy images confirmed disorganised fibrin networks in all patients. Patients with tendency to bleed showed an increased permeability compared to asymptomatic patients (p=0.01) and to patients with a thrombotic history (p=0.02) while patients with thrombotic history had a tendency to have a prolonged clot lysis time. Fibrin clot properties were similar among hotspot mutations. Further studies including a larger number of patients are needed to evaluate whether analysis of permeability and clot lysis time may help to distinguish the clinical phenotype in these patients and to assess differences according to the genotype.

Identification of immunodominant antigens for the laboratory diagnosis of toxocariasis

To identify immunodominant antigens of Toxocara canis recognised by Toxocara-infected sera as recombinant reagents for immunodiagnosis of toxocariasis. Pooled sera from human cases of toxocariasis were used to identify immunodominant antigens by immunoscreening a T. canis larval expression cDNA library. The positive clones were sequenced to reveal the identity of the antigens. The recombinant proteins were expressed in E. coli and then used to confirm their immunoreaction with sera of humans with toxocariasis. Two chosen antigens were also used to differentiate Toxocara infection from other helminth infections in mice. Eleven antigens with immunodiagnostic potential were identified, including two C-type lectins (CTLs) that reacted strongly with the Toxocara-positive serum pool. The first CTL (Tc-CTL-1) is the same as TES-32, previously identified as a major immunodominant component of TES; the second CTL (Tc-CTL-2) is a novel C-type lectin sharing 83% amino acid sequence identity within the functional domain of Tc-CTL-1. The E. coli-expressed recombinant Tc-CTL-1 was strongly recognised by the Toxocara-positive serum pool or sera from animals experimentally infected with T. canis. Reactivity with recombinant Tc-CTL-1 was higher when the unreduced protein was used in an enzyme-linked immunosorbent assay (ELISA), dot-blot assay or Western blot test compared to the protein under reduced condition. Both recombinant Tc-CTL-1- and Tc-CTL-2-based ELISAs were able to differentiate T. canis infection from other helminth infections in experimentally infected mice. Both Tc-CTL-1 and Tc-CTL-2 were able to differentiate Toxocara infection from other helminth infections and could potentially be used as sensitive and specific immunodiagnostic antigens.

Prediction of Changes in Left Ventricular Ejection Fraction after Off-Pump Coronary Artery Bypass Grafting Surgery by Myocardial Perfusion Single-Photon Emission Computed Tomography

Introduction: Left ventricular ejection fraction (LVEF) is considered to be the single most important prognostic factor in patients with previous myocardial infarction. LVEF is not improved in all patients after coronary artery bypass grafting (CABG). This study aimed to assess the possibility of prediction of LVEF changes after CABG using myocardial perfusion gated signle photon emission computed tomography (GSPECT). Materials and Methods: Overall, 48 patients with mean LVEF of 30.2% (±4.7) underwent Echocardiography and GSPECT after injection of Tc-99m-MIBI at rest. Myocardial uptake was evaluated in 17 myocardial segments and was compared with age and gender matched normal data pool. The risks and benefits of CABG were explained to the patients and 16 cases (15 male and 1 female) with the mean age of 61.1 years (±10.8) accepted to undergo off-pump CABG. All the patients were followed-up for at least six months and echocardiography and GSPECT were repeated at the end of follow up. Results: The mean LVEF was increased from of 31.1% (±3.5) to 34.5% (±3.6) after surgery (P<0.001). Delta LVEF was defined as ΔLVEF=LVEF (before CABG) - LVEF (after CABG). ΔLVEF was within the range of 0-8% with the mean of 3.4% (±2.5). The number of non-viable myocardial segments was not significantly different between patients with ΔLVEF ≥ 5% and those with smaller changes. Myocardial perfusion was estimated for all segments, and the mean global uptake was defined by adding the mean uptake in all segments, divided by 17. The mean global uptake was 53.1% in our patients. Regression analysis revealed that ΔLVEF after CABG can be predicted reliably using the following formula: ΔLVEF= -33.8 + (0.77 × mean global uptake) (P<0.01). Conclusion: Our study showed that change of LVEF after CABG can be predicted reliably using mean global uptake in preoperative myocardial perfusion SPECT at rest.

초기 변동수위를 고려한 제방 월류에 따른 안정성 분석

지반공학적으로 제방(또는 댐) 월류에 대한 근거를 제시하기 어렵다. 수문학적인 안정성 평가에서 댐의 초기수위(만수위)를 고정시키고 강우량을 계산하기 때문에 월류 가능성은 매우 희박하다. 그러나 Copula 함수를 사용하여 초기수위가 고정된 댐의 만수위가 아닌 변동성 있는 확률수위를 적용해서 국내 40년간의 빈도를 고려할 때, 월류 가능성을 확인할 수 있었다. 수문학적 댐의 위험성 분석은 다양한 불확실성 인자 중 댐 초기수위에 대한 모의기법 개발이 필요한 복잡한 수문학적 해석을 요구한다. 본 연구에서는 기존 댐 위험도 분석 시 초기수위는 상시만수위 또는 홍수기 제한수위로 가정하지만, 이러한 보수적인 가정에 의한 연구는 기상변동성 및 기후변화의 영향을 고려하지 못하며, 댐의 월류확률 및 이에 따른 붕괴확률을 추정하는데 있어서 지반공학적인 접근이 필요하다. Copula 함수를 이용하여 댐 특성에 맞는 초기수위를 결정하였으며, HEC-5 모형을 활용하여 강우-유출 모형 매개변수의 사후분포를 정량적으로 추정하여 댐 월류확률을 산정하였다. 지반공학적인 측면에서 댐 안정성 해석은 상류사면(upstream)의 수위급강하(drawdown)에 대한 안전율과 하류사면(downstream) 월류상태에서의 불안정성을 비교하여 지반공학적 위험도를 비교 분석하였다. It is not possible to provide resonable evidence for embankment (or dam) overtopping in geotechnical engineering, and conventional analysis by hydrologic design has not provided the evidence for the overflow. However, hydrologic design analysis using Copula function demonstrates the possibility that dam overflow occurs when estimating rainfall probability with rainfall data for 40 years based on fluctuating water level of a dam. Hydrologic dam risk analysis depends on complex hydrologic analyses in that probabilistic relationship needs to be established to quantify various uncertainties associated with modeling process and inputs. The systematic approaches to uncertainty analysis for hydrologic risk analysis have not been addressed yet. In this paper, the initial level of a dam for stability of a dam is generally determined by normal pool level or limiting the level of the flood, but overflow of probability and instability of a dam depend on the sensitivity analysis of the initial level of a dam. In order to estimate the initial level, Copula function and HEC-5 rainfall-runoff model are used to estimate posterior distributions of the model parameters. For geotechnical engineering, slope stability analysis was performed to investigate the difference between rapid drawdown and overtopping of a dam. As a result, the slope instability in overtopping of a dam was more dangerous than that of rapid drawdown condition.

AN INTRUSION DETECTION MODEL BASED ON FUZZY MEMBERSHIP FUNCTION USING GNP

As the Internet facilities increasing over the world, threats, attacks or intrusions over the Internet are also increasing. Therefore, an intrusion detection model is required to detect intrusion that going to threaten CIA of internet resources. A GNP based fuzzy membership function is much more suitable for identifying such kind of intrusions. A GNP which is a combination of GA and GP applied to extract association rules. A combined GNP-fuzzy membership method would help us to extract important association rules from DARPA 98/99 dataset rather than all rules from DARPA 98/99 dataset. Then the extracted association rules would be updated using genetic operations and also stored into rule pool. In classification, association rules will be classified as normal or intrusion based on calculated match degree. The classified association rules will be stored separately in two different rule pools. Normal rules in normal rule pool and intrusion rules in intrusion rule pool. For the new data match degree will be calculated based on available normal rules and intrusion rules. Then this calculated match degree will help us to identify whether the new data normal or intrusion.

UV Radiation Induces the Epidermal Recruitment of Dendritic Cells that Compensate for the Depletion of Langerhans Cells in Human Skin

UVR causes skin injury and inflammation, resulting in impaired immune function and increased skin cancer risk. Langerhans cells (LCs), the immune sentinels of the epidermis, are depleted for several days following a single UVR exposure and can be reconstituted from circulating monocytes. However, the differentiation pathways leading to the recovery of a normal pool of LCs is still unclear. To study the dynamic changes in human skin with UV injury, we exposed a cohort of 29 healthy human volunteers to a clinically relevant dose of UVR and analyzed sequential epidermal biopsies for changes in leukocyte and dendritic cell (DC) subsets. UV-induced depletion of CD1a(high) LC was compensated by sequential appearance of various epidermal leukocytes. CD14(+) monocytes were recruited as early as D1 post exposure, followed by recruitment of two inflammatory DC subsets that may represent precursors of LCs. These CD1a(low) CD207(-) and the heretofore unknown CD1a(low) CD207(+) DCs appeared at day 1 and day 4 post UVR, respectively, and were endowed with T-cell-activating properties similar to those of LCs. We conclude that recruitment of monocytes and inflammatory DCs appear as a physiological response of the epidermis in order to repair UVR-induced LC depletion associated with immune suppression.

Assessment of accumulation rates in small reservoirs by core analysis, 137Cs measurements and bathymetric mapping in Burkina Faso

AbstractReservoir siltation is one of the most important off‐site effects of soil erosion. In Burkina Faso a large number of small dams have been built to store rainfall and runoff water in the rainy season, which is much needed for domestic use, irrigation and stock watering in the dry season. This study quantifies the siltation rates of two small reservoirs in southwestern Burkina Faso by comparing the initial and current reservoir bed morphology and by analyzing variations in accumulated sediment in terms of stratigraphical changes and 137Cs concentrations. Results of a bathymetric survey show that both reservoirs have already lost approximately 10% to 15% of their original storage capacity at normal pool level and more than 60% of their initial inactive storage volume at spillway level in the last 15 to 20 years. During this period, inflow sediment had accumulated on the bottom of the reservoir to a thickness of 0.3 m to 0.5 m. Sediment core measurements confirmed this thickness by showing a clear stratigraphical change in core properties with significant variations in the 137Cs concentrations at these specific depths. The thickness of accumulated sediment on top of the relict soil indicates that the reservoirs have a ‘half‐life’ of about 40 to 45 years before siltation might affect its water supply and flood control. Compared with other reservoir studies in West Africa these siltation rates can be seen as reasonable but not alarmingly high. Nevertheless, many of the small dams built during the 1980s are likely to reach their ‘half‐life’ in about 10 to 20 years causing hydrological and geomorphological changes upstream and downstream of the dams. Therefore, further research studies should focus on prevention measures to reduce the off‐site effects of erosion and thus to slow down the process of siltation. Copyright © 2015 John Wiley &amp; Sons, Ltd.

IL-33 Reverses an Obesity-Induced Deficit in Visceral Adipose Tissue ST2+ T Regulatory Cells and Ameliorates Adipose Tissue Inflammation and Insulin Resistance.

Obesity is associated with insulin resistance and inflammation thought to be caused by a visceral adipose tissue (VAT)-localized reduction in immunoregulatory cells and increase in proinflammatory immune cells. We previously found that VAT regulatory T cells (Tregs) normally express high levels of IL-10 and that expression of this cytokine in VAT Tregs is specifically reduced in mice fed a high-fat diet. In this study, we further investigated the phenotype of VAT Tregs and found that the majority of IL-10-expressing Tregs in the VAT of lean mice also expressed the ST2 chain of the IL-33R. In addition to high expression of IL-10, ST2(+) Tregs in lean VAT expressed higher proportions of Th2-associated proteins, including GATA3 and CCR4, and Neuropillin-1 compared with ST2(-) Tregs. The proportion of ST2(+) Tregs in VAT was severely diminished in obese mice that had been fed a high-fat/sucrose diet, and this effect could be completely reversed by treatment with IL-33. IL-33 treatment also reversed VAT inflammation in obese mice and resulted in a reduction of hyperinsulinemia and insulin resistance. These data suggest that IL-33 contributes to the maintenance of the normal pool of ST2(+) Tregs in the VAT, and that therapeutic administration of IL-33 results in multiple anti-obesity effects, including the reversal of VAT inflammation and alleviation of insulin resistance.

Performance in Measurement of Serum Cystatin C by Laboratories Participating in the College of American Pathologists 2014 CYS Survey.

Cystatin C is becoming an increasingly popular biomarker for estimating glomerular filtration rate, and accurate measurements of cystatin C concentrations are necessary for accurate estimates of glomerular filtration rate. To assess the accuracy of cystatin C concentration measurements in laboratories participating in the College of American Pathologists CYS Survey. Two fresh frozen serum pools, the first from apparently healthy donors and the second from patients with chronic kidney disease, were prepared and distributed to laboratories participating in the CYS Survey along with the 2 usual processed human plasma samples. Target values were established for each pool by using 2 immunoassays and ERM DA471/IFCC international reference material. For the normal fresh frozen pool (ERM-DA471/IFCC-traceable target of 0.960 mg/L), the all-method mean (SD, % coefficient of variation [CV]) reported by all of the 123 reporting laboratories was 0.894 mg/L (0.128 mg/L, 14.3%). For the chronic kidney disease pool (ERM-DA471/IFCC-traceable target of 2.37 mg/L), the all-method mean (SD, %CV) was 2.258 mg/L (0.288 mg/L, 12.8%). There were substantial method-specific biases (mean milligram per liter reported for the normal pool was 0.780 for Siemens, 0.870 for Gentian, 0.967 for Roche, 1.061 for Diazyme, and 0.970 for other/not specified reagents; and mean milligram per liter reported for the chronic kidney disease pool was 2.052 for Siemens, 2.312 for Gentian, 2.247 for Roche, 2.909 for Diazyme, and 2.413 for other/not specified reagents). Manufacturers need to improve the accuracy of cystatin C measurement procedures if cystatin C is to achieve its full potential as a biomarker for estimating glomerular filtration rate.

Estimation of dynamic time activity curves from dynamic cardiac SPECT imaging

Whole-heart coronary flow reserve (CFR) may be useful as an early predictor of cardiovascular disease or heart failure. Here we propose a simple method to extract the time-activity curve, an essential component needed for estimating the CFR, for a small number of compartments in the body, such as normal myocardium, blood pool, and ischemic myocardial regions, from SPECT data acquired with conventional cameras using slow rotation.We evaluated the method using a realistic simulation of 99mTc-teboroxime imaging. Uptake of 99mTc-teboroxime based on data from the literature were modeled. Data were simulated using the anatomically-realistic 3D NCAT phantom and an analytic projection code that realistically models attenuation, scatter, and the collimator-detector response. The proposed method was then applied to estimate time activity curves (TACs) for a set of 3D volumes of interest (VOIs) directly from the projections. We evaluated the accuracy and precision of estimated TACs and studied the effects of the presence of perfusion defects that were and were not modeled in the estimation procedure.The method produced good estimates of the myocardial and blood-pool TACS organ VOIs, with average weighted absolute biases of less than 5% for the myocardium and 10% for the blood pool when the true organ boundaries were known and the activity distributions in the organs were uniform. In the presence of unknown perfusion defects, the myocardial TAC was still estimated well (average weighted absolute bias <10%) when the total reduction in myocardial uptake (product of defect extent and severity) was ≤5%. This indicates that the method was robust to modest model mismatch such as the presence of moderate perfusion defects and uptake nonuniformities. With larger defects where the defect VOI was included in the estimation procedure, the estimated normal myocardial and defect TACs were accurate (average weighted absolute bias ≈5% for a defect with 25% extent and 100% severity).