bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient Estimation of the Partly Linear Additive Hazards Model with Current Status Data
Authors: Lu Xuewen , Song Peter X.‐K.
Published: August 2014

This paper focuses on efficient estimation, optimal rates of convergence and effective algorithms in the partly linear additive hazards regression model with current status data. We use polynomial splines to estimate both cumulative baseline hazard function with monotonicity constraint and nonparametric regression functions with no such constraint. We propose a simultaneous sieve maximum likelihood estimation for regression parameters and nuisance parameters and show that the resultant estimator of regression parameter vector is asymptotically normal and achieves the semiparametric information bound. In addition, we show that rates of convergence for the estimators of nonparametric functions are optimal. We implement the proposed estimation through a backfitting algorithm on generalized linear models. We conduct simulation studies to examine the finite‐sample performance of the proposed estimation method and present an analysis of renal function recovery data for illustration.
Image analysis of skin color heterogeneity focusing on skin chromophores and the age‐related changes in facial skin
Authors: Kikuchi Kumiko , Masuda Yuji , Yamashita Toyonobu , Kawai Eriko , Hirao Tetsuji
Published: August 2014

Background/purpose

Heterogeneity with respect to skin color tone is one of the key factors in visual perception of facial attractiveness and age. However, there have been few studies on quantitative analyses of the color heterogeneity of facial skin. The purpose of this study was to develop image evaluation methods for skin color heterogeneity focusing on skin chromophores and then characterize ethnic differences and age‐related changes.

Methods

A facial imaging system equipped with an illumination unit and a high‐resolution digital camera was used to develop image evaluation methods for skin color heterogeneity. First, melanin and/or hemoglobin images were obtained using pigment‐specific image‐processing techniques, which involved conversion from Commission Internationale de l'Eclairage XYZ color values to melanin and/or hemoglobin indexes as measures of their contents. Second, a spatial frequency analysis with threshold settings was applied to the individual images. Cheek skin images of 194 healthy Asian and Caucasian female subjects were acquired using the imaging system. Applying this methodology, the skin color heterogeneity of Asian and Caucasian faces was characterized.

Results

The proposed pigment‐specific image‐processing techniques allowed visual discrimination of skin redness from skin pigmentation. In the heterogeneity analyses of cheek skin color, age‐related changes in melanin were clearly detected in Asian and Caucasian skin. Furthermore, it was found that the heterogeneity indexes of hemoglobin were significantly higher in Caucasian skin than in Asian skin.

Conclusion

We have developed evaluation methods for skin color heterogeneity by image analyses based on the major chromophores, melanin and hemoglobin, with special reference to their size. This methodology focusing on skin color heterogeneity should be useful for better understanding of aging and ethnic differences.
Islet xenotransplantation: what is the optimal age of the islet‐source pig?
Authors: Nagaraju Santosh , Bottino Rita , Wijkstrom Martin , Trucco Massimo , Cooper David K. C.
Published: August 2014

Background

The need for pig islet xenotransplantation in patients with type 1 diabetes is compelling; however, the ideal age at which islets should be isolated from the donor pig remains uncertain. Pig islet transplantation in primates, as a valuable pre‐clinical model, has been explored using adult, neonatal, fetal pig islets, and also pancreatic primordia from pig embryos as beta cell donors. Neonatal pig islets have some advantages over adult and fetal islets, but the optimal age within the first month of life at which neonatal islets should be isolated and transplanted is as yet unclear.

Methods

In an attempt to answer this question, we carried out a literature search, but limited the search primarily to evidence in the clinically‐relevant pig‐to‐non‐human primate model.

Results

We identified surprisingly few studies in this model directed to this topic. Even in pig‐to‐rodent models, there were few definitive data.

Conclusion

From the few data available to us, we conclude that pancreatectomy and islet isolation from neonatal pigs may have advantages over adult pigs and that isolation during the first week of life may have minor advantages over later weeks.
Conjugate Heat Transfer Computational Fluid Dynamic Predictions of Impingement Heat Transfer: The Influence of Hole Pitch to Diameter Ratio X/D at Constant Impingement Gap Z
Authors: El-Jummah A. M. , Abdul Husain R. A. A. , Andrews G. E. , Staggs J. E. J.
Published: August 2014

Conjugate heat transfer (CHT) computational fluid dynamic (CFD) predictions were carried out for a 10 × 10 square array of impingement holes, for a range of pitch to diameter ratio X/D from 1.9 to 11.0 at a constant impingement gap Z of 10 mm and pitch X of 15.24 mm. The variation of X/D changes the impingement wall pressure loss for the same coolant mass flow rate and also changes the interaction with the impingement gap cross-flow. The experimental technique to determine the surface averaged heat transfer used the lumped capacity method with Nimonic-75 metal walls with imbedded thermocouples and a step change in the hot wall cooling to determine the heat transfer coefficient h from the transient cooling of the metal wall. The test wall was electrically heated to about 80  °C and then transiently cooled by the impingement flow and the lumped capacitance method was used to measure the locally surface average heat transfer coefficient. The predictions and measurements were carried out at an impingement jet mass flux of 1.93 kg/s m2 bar, which is a typical coolant flow rate for regenerative impingement cooling of low NOx gas turbine combustor walls. The computations were conducted for a fixed hot side temperature of 353 K that was imposed at the hot face of the target wall. The wall temperatures as a function of distance along the gap were computed together with the impingement gap aerodynamics. Surface average heat transfer coefficient h and pressure loss predictions were in good agreement with the experimental measurements. However, there was less good agreement for the axial variation of the local surface averaged h for lower values of X/D. The surface averaged heat transfer to the impingement jet wall was also computed and shown to be roughly 70% of target wall impingement heat transfer.
Ultrashort Nacelles for Low Fan Pressure Ratio Propulsors
Authors: Peters Andreas , Spakovszky Zoltán S. , Lord Wesley K. , Rose Becky
Published: August 2014

As the propulsor fan pressure ratio (FPR) is decreased for improved fuel burn, reduced emissions and noise, the fan diameter grows and innovative nacelle concepts with short inlets are required to reduce their weight and drag. This paper addresses the uncharted inlet and nacelle design space for low-FPR propulsors where fan and nacelle are more closely coupled than in current turbofan engines. The paper presents an integrated fan–nacelle design framework, combining a spline-based inlet design tool with a fast and reliable body-force-based approach for the fan rotor and stator blade rows to capture the inlet–fan and fan–exhaust interactions and flow distortion at the fan face. The new capability enables parametric studies of characteristic inlet and nacelle design parameters with a short turn-around time. The interaction of the rotor with a region of high streamwise Mach number at the fan face is identified as the key mechanism limiting the design of short inlets. The local increase in Mach number is due to flow acceleration along the inlet internal surface coupled with a reduction in effective flow area. For a candidate short-inlet design with length over diameter ratio L/D = 0.19, the streamwise Mach number at the fan face near the shroud increases by up to 0.16 at cruise and by up to 0.36 at off-design conditions relative to a long-inlet propulsor with L/D = 0.5. As a consequence, the rotor locally operates close to choke resulting in fan efficiency penalties of up to 1.6% at cruise and 3.9% at off-design. For inlets with L/D < 0.25, the benefit from reduced nacelle drag is offset by the reduction in fan efficiency, resulting in propulsive efficiency penalties. Based on a parametric inlet study, the recommended inlet L/D is suggested to be between 0.25 and 0.4. The performance of a candidate short inlet with L/D = 0.25 was assessed using full-annulus unsteady Reynolds-averaged Navier–Stokes (RANS) simulations at critical design and off-design operating conditions. The candidate design maintains the propulsive efficiency of the baseline case and fuel burn benefits are conjectured due to reductions in nacelle weight and drag compared to an aircraft powered by the baseline propulsor.
Analysis of the Rotordynamic Response of a Centrifugal Compressor Subject to Aerodynamic Loads Due to Rotating Stall
Authors: Biliotti Davide , Bianchini Alessandro , Vannini Giuseppe , Belardini Elisabetta , Giachi Marco , Tapinassi Libero , Ferrari Lorenzo , Ferrara Giovanni
Published: August 2014

In the current industrial research on centrifugal compressors, manufacturers are showing increasing interest in the extension of the minimum stable flow limit in order to improve the operability of each unit. The aerodynamic performance of a compressor stage is indeed often limited before surge by the occurrence of diffuser rotating stall. This phenomenon generally causes an increase of the radial vibrations, which, however, is not always connected with a remarkable performance detriment. In case the operating curve has been limited by a mechanical criterion, i.e., based on the onset of induced vibrations, an investigation on the evolution of the aerodynamic phenomenon when the flow rate is further reduced can provide some useful information. In particular, the identification of the real thermodynamic limit of the system could allow one to verify if the new load condition could be tolerated by the rotordynamic system in terms of radial vibrations. Within this context, recent works showed that the aerodynamic loads due to a vaneless diffuser rotating stall can be estimated by means of test-rig experimental data of the most critical stage. Moreover, by including these data into a rotordynamic model of the whole machine, the expected vibration levels in real operating conditions can be satisfactorily predicted. To this purpose, a wide-range analysis was carried out on a large industrial database of impellers operating in presence of diffuser rotating stall; the analysis highlighted specific ranges for the resultant rotating force in terms of intensity and excitation frequency. Moving from these results, rotordynamic analyses have been performed on a specific case study to assess the final impact of these aerodynamic excitations.
Full Fluid–Solid Cohesive Finite-Element Model to Simulate Near Wellbore Fractures
Authors: Salehi Saeed , Nygaard Runar
Published: August 2014

This paper presents finite-element simulation for hydraulic fracture's initiation, propagation, and sealing in the near wellbore region. A full fluid solid coupling module is developed by using pore pressure cohesive elements. The main objective of this study is to investigate the hypothesis of wellbore hoop stress increase by fracture sealing. Anisotropic stress state has been used with assignment of individual criteria for fracture initiation and propagation. Our results demonstrate that fracture sealing in “wellbore strengthening” cannot increase the wellbore hoop stress beyond its upper limit when no fractures exist. However, this will help to restore part or all of the wellbore hoop stress lost during fracture propagation.
Task Space Impedance Control of the Manipulator Driven Through the Multistage Nonlinear Flexible Transmission
Authors: Pitakwatchara Phongsaen
Published: August 2014

This paper addresses the task space impedance control of a robot driven through the multistage nonlinear flexible transmission. The proposed controller uses limited information of the angle and the current of the motors to regulate the end point compliance at the specified set point. In particular, motor angle is employed to estimate the stationary robot link angle and joint velocity in real time. They are then used to constitute the stationary force on the attempt to cancel the robot gravity force and to form the task space interacting force according to the desired impedance characteristics. Motor current is used to infer the transmitted torque to the robot. This torque is fed back to mitigate the effect of the motor inertia from deteriorating the desired impedance. Asymptotic stability of this controller with the flexible joint robot is guaranteed with additional damping. Passivity of the system is also investigated. Simulation and experiments of the proposed control scheme on a two degrees-of-freedom (DOF) cable-pulley driven flexible joint robot model are examined.
Optimization of Thermoelectric Coolers for Hotspot Cooling in Three-Dimensional Stacked Chips
Authors: Redmond Matthew , Kumar Satish
Published: August 2014

Three-dimensional (3D) chip stacking architecture is expected to reduce form factor, improve performance, and decrease power consumption in future microelectronics. High power density and nonuniform power distribution in stacked dies are expected to bring significant thermal challenges for 3D packages due to localized hot spots. Embedded thermoelectric coolers (TECs) have potential to provide reliable and localized cooling at these hot spots. In this work, peak package temperature or active cooling per power consumption of TECs are optimized, considering applied current and thickness of TECs as parameters, for a 3D electronic package with two stacked dies. Each die has two hot spots and one TEC is paired with each hot spot. Three different optimization methods are considered in order to ensure a robust solution. The optimization suggests that both the peak temperature in package and energy efficiency of the cooling system can be significantly improved through the optimization of TECs. TECs are also compared against a configuration where they are replaced by copper blocks or thermal vias. A total of 4.7 °C of additional localized cooling is observed using TECs which is beyond what is achievable with copper vias in place of the TECs. The study also suggests that it is better to use TECs to cool only the hottest portions of the package to avoid introducing additional thermal resistance and Joule heating in the package.
Analysis and Methodology to Characterize Heat Transfer Phenomena in Automotive Turbochargers
Authors: Serrano J. R. , Olmeda P. , Arnau F. J. , Dombrovsky A. , Smith L.
Published: August 2014

In the present work a comprehensive study of turbocharger heat transfer phenomena is discussed, showing their relevance compared to gas enthalpy variations through the turbomachinery. The study provides an experimental methodology to consider the different heat fluxes in the turbocharger and modeling them by means of a lumped capacitance heat transfer model (HTM). The input data required for the model are obtained experimentally by a proper combination of both steady and transient tests. These tests are performed in different test benches, in which incompressible fluids (oil) and compressible fluids (gas) are used in a given sequence. The experimental data allows developing heat transfer correlations for the different turbocharger elements. These correlations take into account all the possible heat fluxes, discriminating between internal and external heat transfer. In order to analyze the relative importance of heat transfer phenomena in the predictability of the turbocharger performance and the different related variables; model results, in hot and cold conditions, have been compared with those provided by the standard technique, consisting on using look up maps (LUM) of the turbocharger. The analysis of these results evidences the highly diabatic operative areas of the turbocharger and it provides clearly ground rules for using hot or cold turbocharger maps. In addition, paper discussion advises about using or not aHTM, depending on the turbocharger variables and the operative conditions that one desires to predict. Paper concludes that an accurate prediction of gas temperatures at turbine and compressor outlet and of fluid temperatures at water and oil ports outlet is not always possible without considering heat transfer phenomena in the turbocharger.
Modified Chrispin-Norman Score: Correlation With Peak Exercise Capacity and Efficiency of Ventilation in Children With Cystic Fibrosis
Authors: Sovtic Aleksandar , Minic Predrag , Kosutic Jovan , Markovic-Sovtic Gordana , Gajic Milan
Published: August 2014

The modified Chrispin-Norman radiography score (CNS) is used in evaluation of radiographic changes in children with cystic fibrosis (CF). We evaluated the correlation of modified CNS with peak exercise capacity (Wpeak) and ventilatory efficiency (reflected by breathing reserve index—BRI) during progressive cardiopulmonary exercise testing (CPET). Thirty-six children aged 8–17 years were stratified according to their CNS into 3 groups: mild (<10), moderate (10–15), and severe (>15). CPET was performed on a cycle ergometer. Lung function tests included spirometry and whole-body plethysmography. Patients with higher CNS had lower FEV1 (p < .001), Wpeak predicted (%; p = .01) and lower mean peak oxygen consumption (VO2peak/kg; p = .014). The BRI at the anaerobic threshold and at Wpeak was elevated in patients with the highest CNS values (p < .001). The modified CNS correlates moderately with Wpeak (R = −0.443; p = .007) and BRI (R = −0.419; p = .011). Stepwise multiple linear regression showed that RV/TLC was the best predictor of Wpeak/pred (%; B = −0.165; b = −0.494; R2 = .244; p = .002). Children with CF who have high modified CNS exhibit decreased exercise tolerance and ventilatory inefficacy during progressive effort.
Effect of a low-starch/low-dairy diet on fat oxidation in overweight and obese women with polycystic ovary syndrome
Authors: Pohlmeier Ali M. , Phy Jennifer L. , Watkins Phillip , Boylan Mallory , Spallholz Julian , Harris Kitty S. , Cooper Jamie A.
Published: August 2014

Polycystic ovary syndrome (PCOS) affects between 4%–18% of reproductive-aged women and is associated with increased risk of obesity and obesity-related disease. PCOS is associated with hyperinsulinemia, which is known to impair fat oxidation. Research shows that carbohydrates from dairy and starch-based foods cause greater postprandial insulin secretion than carbohydrates from nonstarchy vegetables and fruits. The purpose of this study was to determine whether an ad libitum 8-week low-starch/low-dairy diet would improve fasting and postprandial fat oxidation after a high saturated fat liquid meal (HSFLM) in overweight and obese women with PCOS. Prospective 8-week dietary intervention using a low-starch/low-dairy diet in 10 women (body mass index ≥25 kg/m2 and ≤45 kg/m2) with PCOS. Indirect calorimetry was used at fasting and for 5 h following consumption of the HSFLM to determine respiratory exchange ratio (RER), macronutrient oxidation, and energy expenditure (EE) at week 0 and week 8. Participants had a reduction in body weight (–8.1 ± 1.8 kg, p < 0.05) and fasting insulin (–19.5 ± 8.9 μg/mL, p < 0.05) after dietary intervention; however, these were not significantly correlated with improved fat oxidation. There was a reduction in fasting RER, and fasting and postprandial carbohydrate oxidation, and an increase in fasting and postprandial fat oxidation after adjusting for body weight. There was also significant difference in incremental area under the curve from pre- to post-diet for fat (0.06 ± 0.00 g/kg per 5 h; p < 0.001) and carbohydrate oxidation (–0.29 ± 0.06 g/kg per 5 h; p < 0.001), but not for RER or EE. In conclusion, an 8-week low-starch/low-dairy diet increased fat oxidation in overweight and obese women with PCOS.
Pollen limitation is uncommon in an endangered oak savannah ecosystem
Authors: Gielens Grahame , Gillespie Sandra , Neame Lisa , Elle Elizabeth
Published: August 2014

Pollen receipt limits reproduction in many plants, potentially affecting population viability and trait evolution. Despite considerable research, there is little consensus on the causes of pollen limitation (PL). Reviews suggest spatial and temporal variation in PL may be important for plant reproductive fitness, yet few studies have examined PL in multiple species across sites and years. We examined how pollinator communities affected PL in six wildflower species across six sites and 2 years. Although our study was conducted in a fragmented ecosystem and on perennial species (both are associated with PL in meta-analyses), we found that PL was uncommon. The degree of PL was highly variable among years, sites, and species, with no species or site showing consistent PL. Variation in PL among sites and years was not explained by variation in diversity or visit rate of the pollinating fauna. The rarity of PL in this study may limit our assessment of the importance of pollinators, but our results do suggest that PL is highly context-dependent, which should be a focus for future work.
Stable spin states of boron, aluminum and silicon dimers in a self-consistent GW calculation
Authors: Kuwahara Riichi , Ohno Kaoru
Published: August 2014

Some small clusters, in particular dimers (diatomic molecules), composed of nonmagnetic atoms exhibit intrinsic spin magnetic moments. In this paper, we discuss the most stable spin state of boron, aluminum and silicon dimers. In order to treat the dynamically screened exchange interaction between electrons correctly, we adopt the self-consistent GW approximation in many-body perturbation theory. We find that the energy gain of the triplet ground state from the singlet excited state as a reference is mainly caused by the dynamically screened exchange interaction, although other contributions to the total energy do not have the same tendency between the triplet and singlet states. We also explicitly show the resulting quasiparticle energy spectra which can be compared with the photoemission and inverse photoemission spectroscopy measurements.
Experimental Investigation and Theoretical Modeling of Nanosilica Activity in Concrete
Authors: Lee Han-Seung , Cho Hyeong-Kyu , Wang Xiao-Yong
Published: August 2014

This paper presents experimental investigations and theoretical modeling of the hydration reaction of nanosilica blended concrete with different water‐to‐binder ratios and different nanosilica replacement ratios. The developments of chemically bound water contents, calcium hydroxide contents, and compressive strength of Portland cement control specimens and nanosilica blended specimens were measured at different ages: 1 day, 3 days, 7 days, 14 days, and 28 days. Due to the pozzolanic reaction of nanosilica, the contents of calcium hydroxide in nanosilica blended pastes are considerably lower than those in the control specimens. Compared with the control specimens, the extent of compressive strength enhancement in the nanosilica blended specimens is much higher at early ages. Additionally, a blended cement hydration model that considers both the hydration reaction of cement and the pozzolanic reaction of nanosilica is proposed. The properties of nanosilica blended concrete during hardening were evaluated using the degree of hydration of cement and the reaction degree of nanosilica. The calculated chemically bound water contents, calcium hydroxide contents, and compressive strength were generally consistent with the experimental results.
Histological Distinction between the Granular and Nongranular Types of Laterally Spreading Tumors of the Colorectum
Authors: Goto Shingo P. , Sakamoto Naoto , Mitomi Hiroyuki , Murakami Takashi , Ritsuno Hideaki , Ueyama Hiroya , Matsumoto Kenshi , Shibuya Tomoyoshi , Osada Taro , Nagahara Akihito , Ogihara Tatsuo , Yao Takashi , Watanabe Sumio
Published: August 2014

Colorectal laterally spreading tumors (LSTs), which are classified into granular (LST-G) and nongranular (LST-NG) types, are a good indication for endoscopic treatment. In practice, the nongranular type is more difficult to remove endoscopically than the granular type. It might be assumed that some histological differences exist between these subtypes. The objective of this study was to analyze histological features of laterally spreading tumors and compare between the granular and the nongranular types. A total of 32 cases of LSTs resected endoscopically being intramucosal tumors with no previous treatment were analyzed. The disposition of the muscularis mucosae, the vascular density, and the degree of fibrosis of the submucosal layer were determined. The outline of the muscularis mucosae in LST-NG was almost flat, but that of LST-G was wavy. The submucosal vascular density was significantly greater in the LST-NGs (61.4±24.3/mm2) than in the LST-Gs (43±22.4/mm2;P=0.033). There was no clear difference in the degree of submucosal fibrosis between the subtypes. A flat disposition of the muscularis mucosae and a more densely vascularized submucosal layer were characteristics of LST-NGs compared to the LST-Gs. These findings may play a role when performing the endoscopic resection of LSTs.
The Impact of Cooperative Social Organization on Reducing the Prevalence of Malaria and Intestinal Parasite Infections in Awramba, a Rural Community in South Gondar, Ethiopia
Authors: Yihenew Gebeyehu , Adamu Haileeyesus , Petros Beyene
Published: August 2014

Introduction.Parasitic diseases are the major causes of human health problem in Ethiopia. The high prevalence of parasitic infections is closely correlated with poverty, poor environmental hygiene, and impoverished health services.Objective.The study was conducted to assess the impact of health-conscious Awramba cooperative community and its neighboring communities on the prevalence of parasitic infections in South Gondar, Ethiopia.Methods.Single stool specimens were collected from 392 individuals from Awramba and the neighboring communities. Specimens were examined microscopically for the presence of parasites using microscopy. Questionnaire was administered to determine the knowledge attitude and practice (KAP) of study participants.Results.Of the total 392 study participants examined, 58(14.8%) were positive for malaria and 173 (44.1%) for intestinal parasites. The prevalence of malaria in Awramba community (5.1%) was less than that in neighboring communities (24.5%). The prevalence of parasitic infections in Awramba (18.8%) was less than that of the neighboring communities (69.4%).Conclusion.This study showed that good household and environmental hygiene, good toilet construction and usage, and proper utilization of ITN in Awramba cooperative community have significantly contributed to the reduction of the burden of parasitic infections. Thus, the positive achievement in reducing parasitic infections in Awramba cooperative community could be used as a model for affordable health intervention in the neighboring communities, in particular, and the whole country in general.
Pseudo Asymptotic Behavior of Mild Solution for Nonautonomous Integrodifferential Equations with Nondense Domain
Authors: Xia Zhinan
Published: August 2014

By the weighted ergodic function based on the measure theory, we study pseudo asymptotic behavior of mild solution for nonautonomous integrodifferential equations with nondense domain. The existence and uniqueness ofμ-pseudo antiperiodic (μ-pseudo periodic,μ-pseudo almost periodic, andμ-pseudo automorphic) solution are investigated. Some interesting examples are presented to illustrate the main findings.
Small Bowel Endoscopy Diagnostic Yield and Reasons of Obscure GI Bleeding in Chinese Patients
Authors: He Ya-Fei , Hao Ning-Bo , Yang Wu-Chen , Yang Li , Liao Zhong-Li , Fan Chao-Qiang , Yu Jin , Bai Jian-Ying , Yang Shi-Ming , Guo Hong
Published: August 2014

Aim. To investigate the diagnostic yield and etiologies of patients with obscure gastrointestinal bleeding (OGIB) using capsule endoscopy (CE) or double-balloon enteroscopy (DBE).Method. We studied the data of 532 consecutive patients with OGIB that were referred to Xinqiao Hospital in Chongqing from December 2005 to January 2012. A lesion that was believed to be the source of the bleeding (ulceration, mass lesion, vascular lesion, visible blood, inflammation, or others) was considered to be a positive finding. We analyzed the diagnostic yield of CE and SBE and the etiologies of OGIB.Result. CE and SBE have similar diagnostic yields, at 71.9% (196/231) and 71.8% (251/304), respectively. The most common etiology was erosions/ulceration (27.1%) followed by mass lesion (19.4%) and angiodysplastic/vascular lesions (13.9%). By stratified analysis, we found that erosions/ulceration (27.1%) was the most common etiology for the 21–40-year age group. Mass lesion was the most common etiology in the 41–60-year age group. However, in the >60 years age group, angiodysplastic/vascular lesions were significantly increased compared with the other groups, even though erosions/ulceration was most common.Conclusion. In this study, we found that CE and SBE have similar diagnostic yields and erosions/ulceration was the most common reason for OGIB, followed by mass lesion and angiodysplasias.
Aerosol Number Concentrations and Visibility during Dense Fog over a Subtropical Urban Site
Authors: Mohan Manju , Payra Swagata
Published: August 2014

There is now enough evidence of greater frequencies and extent of fog formation in urban areas. These could easily be linked to rapid increase in aerosol number concentration (ANC) peculiar to polluted urban environments. It is therefore pertinent to study ANC and visibility alongside the meteorological parameters in order to investigate the relationships which may possibly exist between these parameters especially during foggy conditions. This study based on field measurements of ANC for aerosol spectrum varying from 0.3 µm to 20 µm attempts to investigates whether a threshold ANC could be associated with a given visibility range during low visibility conditions including dense fog episodes. Thus, the present work explores relationship between ANC size spectrum and visibility (100 m–4500 m) in a polluted urban environment in India with specific reference to episodes of dense fog during winter period. The study depicts a threshold minimum value of ANC during foggy conditions. A power relationship between ANC and visibility is obtained. Further, aerosol number distribution and size distribution function are also studied and empirical relation is compared with previous studies. Further work is suggested to strengthen the findings presented here.
Ticlopidine in Its Prodrug Form Is a Selective Inhibitor of Human NTPDase1
Authors: Lecka Joanna , Fausther Michel , Künzli Beat , Sévigny Jean
Published: August 2014

Nucleoside triphosphate diphosphohydrolase-1 (NTPDase1), like other ectonucleotidases, controls extracellular nucleotide levels and consequently their (patho)physiological responses such as in thrombosis, inflammation, and cancer. Selective NTPDase1 inhibitors would therefore be very useful. We previously observed that ticlopidine in its prodrug form, which does not affect P2 receptor activity, inhibited the recombinant form of human NTPDase1 (Ki=14 μM). Here we tested whether ticlopidine can be used as a selective inhibitor of NTPDase1. We confirmed that ticlopidine inhibits NTPDase1 in different forms and in different assays. The ADPase activity of intact HUVEC as well as of COS-7 cells transfected with human NTPDase1 was strongly inhibited by 100 µM ticlopidine, 99 and 86%, respectively. Ticlopidine (100 µM) completely inhibited the ATPase activity of NTPDase1in situas shown by enzyme histochemistry with human liver and pancreas sections. Ticlopidine also inhibited the activity of rat and mouse NTPDase1 and of potato apyrase. At 100 µM ticlopidine did not affect the activity of human NTPDase2, NTPDase3, and NTPDase8, nor of NPP1 and NPP3. Weak inhibition (10–20%) of NTPDase3 and -8 was observed at 1 mM ticlopidine. These results show that ticlopidine is a specific inhibitor of NTPDase1 that can be used in enzymatic and histochemistry assays.
NIM: A Node Influence Based Method for Cancer Classification
Authors: Wang Yiwen , Yao Min , Yang Jianhua
Published: August 2014

The classification of different cancer types owns great significance in the medical field. However, the great majority of existing cancer classification methods are clinical-based and have relatively weak diagnostic ability. With the rapid development of gene expression technology, it is able to classify different kinds of cancers using DNA microarray. Our main idea is to confront the problem of cancer classification using gene expression data from a graph-based view. Based on a new node influence model we proposed, this paper presents a novel high accuracy method for cancer classification, which is composed of four parts: the first is to calculate the similarity matrix of all samples, the second is to compute the node influence of training samples, the third is to obtain the similarity between every test sample and each class using weighted sum of node influence and similarity matrix, and the last is to classify each test sample based on its similarity between every class. The data sets used in our experiments are breast cancer, central nervous system, colon tumor, prostate cancer, acute lymphoblastic leukemia, and lung cancer. experimental results showed that our node influence based method (NIM) is more efficient and robust than the support vector machine,K-nearest neighbor, C4.5, naive Bayes, and CART.
Myeloid-Derived microRNAs, miR-223, miR27a, and miR-652, Are Dominant Players in Myeloid Regulation
Authors: Gilicze Anna B. , Wiener Zoltán , Tóth Sára , Buzás Edit , Pállinger Éva , Falcone Franco H. , Falus András
Published: August 2014

In the past few years expanding knowledge has been accumulated about the role of microRNAs (miRNAs) not only in hematopoiesis and cancer, but also in inflammatory and infectious diseases. Regarding myeloid cells, our knowledge is relatively insufficient, therefore we intended to collect the available data of miRNA profiles of myeloid cells. In addition to a rather general myeloid regulator miR-223, two other miRNAs seem to be useful subjects in understanding of myeloid miRNA biology: miR-27a and miR-652. We review functions of these three miRNAs and other myeloid miRNAs focusing on their roles in monocytes, neutrophils, eosinophils, basophils and mast cells.
Phenolic Acids (Gallic and Tannic Acids) Modulate Antioxidant Status and Cisplatin Induced Nephrotoxicity in Rats
Authors: Akomolafe Seun F. , Akinyemi Ayodele J. , Anadozie Scholarstical O.
Published: August 2014

Cisplatin (cis-diamminedichloroplatinum (II) or CDDP), used in the treatment of many solid-tissue cancers, has its chief side-effect in nephrotoxicity. Hence, this study sought to investigate and compare the protective effect of gallic acid (GA) and tannic acid (TA) against cisplatin induced nephrotoxicity in rats. The rats were given a prophylactic treatment of GA and TA orally at a dose of 20 and 40 mg/kg body weight for 7 consecutive days before the administration of a single intraperitoneal (i.p.) injection of cisplatin (CP) at 7.5 mg/kg bwt. The protective effects of both GA and TA on CP induced nephrotoxicity were investigated by assaying renal function, oxidative stress biomarkers, and histopathological examination of kidney architecture. A single dose of cisplatin (7.5 mg/kg bwt) injected i.p. caused a significant increase in some biomarkers of renal function (creatinine, uric acid, and urea levels), with a marked elevation in malondialdehyde (MDA) content accompanied by a significant (P<0.05) decrease in reduced glutathione (GSH) content (103.27%) of kidney tissue as compared to control group. Furthermore, a significant (P<0.05) reduction in kidney antioxidant enzymes (SOD, catalase, GPx, and GST) activity was observed. However, pretreatment with oral administration of tannic acid and gallic acid at a dose of 20 and 40 mg/kg body weight, respectively, for 7 days prior to cisplatin administration reduced histological renal damage and suppressed the generation of ROS, lipid peroxidation, and oxidative stress in kidney tissues. These results indicate that both gallic and tannic acids could serve as a preventive strategy against cisplatin induced nephrotoxicity.
Performance Assessment of Patient on Dialysis
Authors: Manfredini Fabio , Lamberti Nicola
Published: August 2014

Patients on dialysis are poorly active and show a low level of physical functioning. Questionnaires and objective measurements of spontaneous physical activity are available as well as complex-expensive or simple-unexpensive tests useful to assess the patient's exercise capacity. Performance assessment unravels patients' capabilities, enables a tailored exercise prescription and provides predictive information on main clinical outcomes and therefore this topic should be of interest for nephrologists. A routinary minimal pool of tests might be usefully performed in a dialysis centre to stratify the patient's risk and to recognize patients in need of exercise training in order to address them to community-based or rehabilitative programs.
A “Nephrological” Approach to Physical Activity
Authors: Aucella Filippo , Gesuete Antonio , Battaglia Yuri
Published: August 2014

Despite consensus among nephrologists that exercise is important and probably beneficial for their patients, assessment of physical function or encouragement of physical activity is not a part of the routine management of patients with CKD. In order to plan an useful strategy for exercise training we need to clearly define some questions. First of all, nephrologists need to be aware of physical exercise benefits; lack of motivation and increased perceived risk by health care professionals have been identified as contributing factors to physical inactivity. Moreover, the main elements necessary for sustaining exercise programs in this population have to take in account, such as the requirement of exercise professionals, equipment and space, individual prescription, adequate commitment from dialysis and medical staff. When PA may not be implemented, a comprehensive, individualized occupational therapy program may improve functional independence and activity of daily living. Finally, physical function has to be careful monitored and assesses by medical staff.
Physical Performance and Clinical Outcomes in Dialysis Patients: A Secondary Analysis of the Excite Trial
Authors: Torino Claudia , Manfredini Fabio , Bolignano Davide , Aucella Filippo , Baggetta Rossella , Barillà Antonio , Battaglia Yuri , Bertoli Silvio , Bonanno Graziella , Castellino Pietro , Ciurlino Daniele , Cupisti Adamasco , D'Arrigo Graziella , De Paola Luciano , Fabrizi Fabrizio , Fatuzzo Pasquale , Fuiano Giorgio , Lombardi Luigi , Lucisano Gaetano , Messa Piergiorgio , Rapanà Renato , Rapisarda Francesco , Rastelli Stefania , Rocca-Rey Lisa , Summaria Chiara , Zuccalà Alessandro , Tripepi Giovanni , Catizone Luigi , Zoccali Carmine , Mallamaci Francesca ,   EXCITE Working Group
Published: August 2014

Background/Aims: Scarce physical activity predicts shorter survival in dialysis patients. However, the relationship between physical (motor) fitness and clinical outcomes has never been tested in these patients. Methods: We tested the predictive power of an established metric of motor fitness, the Six-Minute Walking Test (6MWT), for death, cardiovascular events and hospitalization in 296 dialysis patients who took part in the trial EXCITE (ClinicalTrials.gov Identifier: NCT01255969). Results: During follow up 69 patients died, 90 had fatal and non-fatal cardiovascular events, 159 were hospitalized and 182 patients had the composite outcome. In multivariate Cox models - including the study allocation arm and classical and non-classical risk factors - an increase of 20 walked metres during the 6MWT was associated to a 6% reduction of the risk for the composite end-point (P=0.001) and a similar relationship existed between the 6MWT, mortality (P<0.001) and hospitalizations (P=0.03). A similar trend was observed for cardiovascular events but this relationship did not reach statistical significance (P=0.09). Conclusions: Poor physical performance predicts a high risk of mortality, cardiovascular events and hospitalizations in dialysis patients. Future studies, including phase-2 EXCITE, will assess whether improving motor fitness may translate into better clinical outcomes in this high risk population.
Monitoring Disease Activity and Progression in Crohn's Disease. A Swiss Perspective on the IBD Ahead ‘Optimised Monitoring' Recommendations
Authors: Sauter Bernhard , Beglinger Christoph , Girardin Marc , Macpherson Andrew , Michetti Pierre , Schoepfer Alain , Seibold Frank , Vavricka Stephan R. , Rogler Gerhard ,   IBD Ahead Swiss National Steering Committee
Published: August 2014

Background and Aims: The structured IBD Ahead ‘Optimised Monitoring' programme was designed to obtain the opinion, insight and advice of gastroenterologists on optimising the monitoring of Crohn's disease activity in four settings: (1) assessment at diagnosis, (2) monitoring in symptomatic patients, (3) monitoring in asymptomatic patients, and (4) the postoperative follow-up. For each of these settings, four monitoring methods were discussed: (a) symptom assessment, (b) endoscopy, (c) laboratory markers, and (d) imaging. Based on literature search and expert opinion compiled during an international consensus meeting, recommendations were given to answer the question ‘which diagnostic method, when, and how often'. The International IBD Ahead Expert Panel advised to tailor this guidance to the healthcare system and the special prerequisites of each country. The IBD Ahead Swiss National Steering Committee proposes best-practice recommendations adapted for Switzerland. Methods: The IBD Ahead Steering Committee identified key questions and provided the Swiss Expert Panel with a structured literature research. The expert panel agreed on a set of statements. During an international expert meeting the consolidated outcome of the national meetings was merged into final statements agreed by the participating International and National Steering Committee members - the IBD Ahead ‘Optimized Monitoring' Consensus. Results: A systematic assessment of symptoms, endoscopy findings, and laboratory markers with special emphasis on faecal calprotectin is deemed necessary even in symptom-free patients. The choice of recommended imaging methods is adapted to the specific situation in Switzerland and highlights the importance of ultrasonography and magnetic resonance imaging besides endoscopy. Conclusion: The recommendations stress the importance of monitoring disease activity on a regular basis and by objective parameters, such as faecal calprotectin and endoscopy with detailed documentation of findings. Physicians should not rely on symptoms only and adapt the monitoring schedule and choice of options to individual situations.
Liquid-Based Cytology in Fine-Needle Aspiration of Breast Lesions: A Review
Authors: Gerhard Rene , Schmitt Fernando C.
Published: August 2014

Objective: Fine-needle aspiration (FNA) is a safe and cost-effective technique for the diagnosis of breast lesions, especially when correlated with clinical and imaging studies. However, the success of breast FNA is highly dependent on the adequate preparation of cytological conventional smears (CS). The liquid-based cytology (LBC) technique consists of an automated method for preparing thin-layer cytological samples from cell suspensions collected in alcohol-based preservative. LBC is designed to improve CS by avoiding limiting factors such as obscuring material, air-drying and smearing artifacts. Study Design: We performed a review of the published literature about LBC applied to breast FNA. Results: LBC preparations of breast aspirates demonstrated better cellular preservation, less cell overlapping and elimination of blood and excessive inflammation compared to CS. Conversely, alterations in architecture and cell morphology as well as loss of myoepithelial cells and stromal elements have been described in LBC specimens, requiring training before applying this technique for diagnosis. Studies have shown a similar accuracy between LBC and CS for the diagnosis of breast lesions. LBC also permits the use of residual material for ancillary tests, which is an important advantage compared to CS. Conclusions: LBC can be safely applied to breast FNA, showing a similar diagnostic accuracy to CS.
Role of Dietary Fats in the Prevention and Treatment of the Metabolic Syndrome
Authors: Nettleton Joyce A. , Jebb Susan , Risérus Ulf , Koletzko Berthold , Fleming Jennifer
Published: August 2014

A symposium on the health significance of dietary fat in the prevention and treatment of the metabolic syndrome (MetS) was held at the 20th International Congress of Nutrition in Granada, Spain, on September 19, 2013. Four nutrition experts addressed the topics of dietary fat and obesity, effects of dietary fat quality in obesity and insulin resistance, influence of early nutrition on the later risk of MetS and the relative merits of high- or low-fat diets in counteracting MetS. Participants agreed that preventing weight gain and achieving weight loss in overweight and obese patients were key strategies for reducing MetS. Both low-fat and low-carbohydrate diets are associated with weight loss, but adherence to the diet is the most important factor in achieving success. Avoidance of high saturated fats contributes to lower health risks among obese, MetS and diabetic patients. Further, healthy maternal weight at conception and in pregnancy is more important that weight gain during pregnancy for reducing the risk of obesity in the offspring. The effects of different polyunsaturated fatty acids on MetS and weight loss require clarification.
Accuracy of Cytotechnologist Evaluation of Specimen Adequacy and Screening Interpretation of Malignancy in Fine-Needle Aspiration of the Liver
Authors: Ahmed Aadil , Novak Anna B. , Farhat Sheerin Aisha , Boonyaarunnate Thiraphon , Ali Syed Z. , Olson Matthew T.
Published: August 2014

Objective: To evaluate the performance of cytotechnologists in assessing the adequacy and accuracy of the preliminary diagnosis for fine-needle aspirates of the liver. Study Design: We retrospectively analyzed 10 years of data and found 589 cases of ultrasound-guided fine-needle aspiration (FNA) of the liver with on-site evaluation of adequacy (OSEA). All the OSEA were performed by the cytopathologist because OSEA of liver FNA is not performed by cytotechnologists at our institution at present. After OSEA, the material was seen by cytotechnologists who rendered an adequacy assessment and preliminary diagnosis. We calculated the adequacy and accuracy statistics and compared the performance of the cytotechnologists with the OSEA and final interpretation. Results: There was no statistically significant difference in adequacy downgrade rate for cytotechnologist versus cytopathologist assessment during the study period (5 vs. 3%, p = 0.06). A total agreement of 88% was noted in overall diagnosis with 97% agreement in malignant cases. Conclusion: Cytotechnologists assess the adequacy of liver FNA accurately and there is therefore potential for them to perform OSEA for liver FNA.