bluuebunny/crossref_metadata_2025 huggingface dataset:
Modular organization of balance control following perturbations during walking
Authors: Oliveira Anderson Souza Castelo , Gizzi Leonardo , Kersting Uwe Gustav , Farina Dario
Published: July 2012

Balance recovery during walking requires complex sensory-motor integration. Mechanisms to avoid falls are active concomitantly with human locomotion motor patterns. It has been suggested that gait can be described by a set of motor modules (synergies), but little is known on the modularity of gait during recovery of balance due to unexpected slips. Our hypothesis was that muscular activation during reactive recovery of balance during gait has a modular organization. The aim of the study was to verify this hypothesis when perturbations were delivered in different directions. Eight healthy men walked on a 7-m walkway, which had a moveable force platform embedded in the middle. Subjects experienced unperturbed walking as well as perturbations delivered in the sagittal (forward and backward) and frontal (leftward and rightward) planes. Bilateral full-body kinematics and surface electromyography (EMG) from lower limbs, trunk, and neck were recorded during walking. Synergies and activation signals were extracted from surface EMG signals. Four modules were sufficient to explain the unperturbed gait and the gait perturbed in any of the perturbation directions. Moreover, three of four modules extracted from the unperturbed gait were the same for gait perturbed forward, leftward, and rightward (similarity in synergies = 0.94 ± 0.03). On the other hand, the activation signals were different between unperturbed and perturbed gait (average correlation coefficient = 0.55 ± 0.16). These strategies to recover balance were robust across subjects. In conclusion, changes in lower limb and trunk kinematics provoked by perturbations were reflected in minimal adjustments in the muscular modular organization of walking, with three of four modules preserved from normal walking. Conversely, the activation signals were all substantially influenced by the perturbations, being the result of integration of afferent information and supraspinal control.
Receptive field properties and intensity-response functions of polarization-sensitive neurons of the optic tubercle in gregarious and solitarious locusts
Authors: el Jundi Basil , Homberg Uwe
Published: July 2012

Many migrating insects rely on the plane of sky polarization as a cue to detect spatial directions. Desert locusts ( Schistocerca gregaria), like other insects, perceive polarized light through specialized photoreceptors in a dorsal eye region. Desert locusts occur in two phases: a gregarious swarming phase, which migrates during the day, and a solitarious nocturnal phase. Neurons in a small brain area, the anterior optic tubercle (AOTu), are critically involved in processing polarized light in the locust brain. While polarization-sensitive intertubercle cells [lobula-tubercle neuron 1 (LoTu1) and tubercle-tubercle neuron 1 (TuTu1)] interconnect the AOTu of both hemispheres, tubercle-lateral accessory lobe tract (TuLAL1) neurons transmit sky compass signals to a polarization compass in the central brain. To better understand the neural network underlying polarized light processing in the AOTu and to investigate possible adaptations of the polarization vision system to a diurnal versus nocturnal lifestyle, we analyzed receptive field properties, intensity-response relationships, and daytime dependence of responses of AOTu neurons in gregarious and solitarious locusts. Surprisingly, no differences in the physiology of these neurons were found between the two locust phases. Instead, clear differences were observed between the different types of AOTu neurons. Whereas TuTu1 and TuLAL1 neurons encoded E-vector orientation independent of light intensity and would thus be operational in bright daylight, LoTu1 neurons were inhibited by high light intensity and provided strong polarization signaling only under dim light conditions. The presence of high- and low-intensity polarization channels might, therefore, allow solitarious and gregarious locusts to use the same polarization coding system despite their different activity cycles.
Selective bilateral activation of leg muscles after cutaneous nerve stimulation during backward walking
Authors: Hoogkamer Wouter , Massaad Firas , Jansen Karen , Bruijn Sjoerd M. , Duysens Jacques
Published: July 2012

During human locomotion, cutaneous reflexes have been suggested to function to preserve balance. Specifically, cutaneous reflexes in the contralateral leg's muscles (with respect to the stimulus) were suggested to play an important role in maintaining stability during locomotor tasks where stability is threatened. We used backward walking (BW) as a paradigm to induce unstable gait and analyzed the cutaneous reflex activity in both ipsilateral and contralateral lower limb muscles after stimulation of the sural nerve at different phases of the gait cycle. In BW, the tibialis anterior (TA) reflex activity in the contralateral leg was markedly higher than TA background EMG activity during its stance phase. In addition, in BW a substantial reflex suppression was observed in the ipsilateral biceps femoris during the stance-swing transition in some participants, while for medial gastrocnemius the reflex activity was equal to background activity in both legs. To test whether the pronounced crossed responses in TA could be related to instability, the responses were correlated with measures of stability (short-term maximum Lyapunov exponents and step width). These measures were higher for BW compared with forward walking, indicating that BW is less stable. However, there was no significant correlation between these measures and the amplitude of the crossed TA responses in BW. It is therefore proposed that these crossed responses are related to an attempt to briefly slow down (TA decelerates the center of mass in the single-stance period) in the light of unexpected perturbations, such as provided by the sural nerve stimulation.
Foetal Haemoglobin, Erythrocytes Containing Foetal Haemoglobin, and Hematological Features in Congolese Patients with Sickle Cell Anaemia
Authors: Tshilolo L. , Summa V. , Gregorj C. , Kinsiama C. , Bazeboso J. A. , Avvisati G. , Labie D.
Published: July 2012

High HbF levels and F cells are correlated with reduced morbidity and mortality in sickle cell disease (SCD). This paper was designed to determine the HbF and F cells levels in Congolese sickle cell anemia (SCA) patients in order to determine their impact on the expression of SCD.Population and Method. HbF levels were measured in 89 SCA patients (mean age 11.4 yrs) using a standard HPLC method. F cell quantitation was done in a second group of SCA patients (, mean age 8.9 yrs) and compared with a control group (, mean age 5 yrs). F cells were quantified by a cytofluorometric system (MoAb-HbF—FITC; cut off at 0.5%).Results. The mean value of HbF was 7.2%  5.0 with heterogeneous distribution, most patients (76%) having HbF < 8%. Mean values of F-cells in SCA patients and control group were 5.4%  7.6 (median: 2.19% ; range 0,0–30,3%) and 0.5%  1.6 (median 0.0, range 0–5.18), respectively. SCA patients with F cells >4.5% developed less painful crisis and had higher percentage of reticulocytes.Conclusion. Congolese SCA patients displayed low levels of HbF and F-cells that contribute to the severity of SCD.
Nanotechnological Strategies for Biofabrication of Human Organs
Authors: Rezende Rodrigo A. , Azevedo Fábio de Souza , Pereira Frederico David , Kasyanov Vladimir , Wen Xuejun , de Silva Jorge Vicente Lopes , Mironov Vladimir
Published: July 2012

Nanotechnology is a rapidly emerging technology dealing with so-called nanomaterials which at least in one dimension have size smaller than 100 nm. One of the most potentially promising applications of nanotechnology is in the area of tissue engineering, including biofabrication of 3D human tissues and organs. This paper focused on demonstrating how nanomaterials with nanolevel size can contribute to development of 3D human tissues and organs which have macrolevel organization. Specific nanomaterials such as nanofibers and nanoparticles are discussed in the context of their application for biofabricating 3D human tissues and organs. Several examples of novel tissue and organ biofabrication technologies based on using novel nanomaterials are presented and their recent limitations are analyzed. A robotic device for fabrication of compliant composite electrospun vascular graft is described. The concept of self-assembling magnetic tissue spheroids as an intermediate structure between nano- and macrolevel organization and building blocks for biofabrication of complex 3D human tissues and organs is introduced. The design of in vivo robotic bioprinter based on this concept and magnetic levitation of tissue spheroids labeled with magnetic nanoparticles is presented. The challenges and future prospects of applying nanomaterials and nanotechnological strategies in organ biofabrication are outlined.
Monitoring Murder Crime in Namibia Using Bayesian Space-Time Models
Authors: Neema Isak , Böhning Dankmar
Published: July 2012

This paper focuses on the analysis of murder in Namibia using Bayesian spatial smoothing approach with temporal trends. The analysis was based on the reported cases from 13 regions of Namibia for the period 2002–2006 complemented with regional population sizes. The evaluated random effects include space-time structured heterogeneity measuring the effect of regional clustering, unstructured heterogeneity, time, space and time interaction and population density. The model consists of carefully chosen prior and hyper-prior distributions for parameters and hyper-parameters, with inference conducted using Gibbs sampling algorithm and sensitivity test for model validation. The posterior mean estimate of the parameters from the model using DIC as model selection criteria show that most of the variation in the relative risk of murder is due to regional clustering, while the effect of population density and time was insignificant. The sensitivity analysis indicates that both intrinsic and Laplace CAR prior can be adopted as prior distribution for the space-time heterogeneity. In addition, the relative risk map show risk structure of increasing north-south gradient, pointing to low risk in northern regions of Namibia, while Karas and Khomas region experience long-term increase in murder risk.
Demonstrated Wavelength Portability of Raman Reference Data for Explosives and Chemical Detection
Authors: Johnson Timothy J. , Su Yin-Fong , Jarman Kristin H. , Kunkel Brenda M. , Birnbaum Jerome C. , Joly Alan G. , Stephan Eric G. , Tonkyn Russell G. , Ewing Robert G. , Dunham Glen C.
Published: July 2012

As Raman spectroscopy continues to evolve, questions arise as to the portability of Raman data: dispersive versus Fourier transform, wavelength calibration, intensity calibration, and in particular the frequency of the excitation laser. While concerns about fluorescence arise in the visible or ultraviolet, most modern (portable) systems use near-infrared excitation lasers, and many of these are relatively close in wavelength. We have investigated the possibility of porting reference data sets from one NIR wavelength system to another: We have constructed a reference library consisting of 145 spectra, including 20 explosives, as well as sundry other compounds and materials using a 1064 nm spectrometer. These data were used as a reference library to evaluate the same 145 compounds whose experimental spectra were recorded using a second 785 nm spectrometer. In 128 cases of 145 (or 88.3% including 20/20 for the explosives), the compounds were correctly identified with a mean “hit score” of 954 of 1000. Adding in criteria for when to declare a correct match versus when to declare uncertainty, the approach was able to correctly categorize 134 out of 145 spectra, giving a 92.4% accuracy. For the few that were incorrectly identified, either the matched spectra were spectroscopically similar to the target or the 785 nm signal was degraded due to fluorescence. The results indicate that imported data recorded at a different NIR wavelength can be successfully used as reference libraries, but key issues must be addressed: the reference data must be of equal or higher resolution than the resolution of the current sensor, the systems require rigorous wavelength calibration, and wavelength-dependent intensity response should be accounted for in the different systems.
Characteristics of InGaN‐Based Light‐Emitting Diodes on Patterned Sapphire Substrates with Various Pattern Heights
Authors: Yu Sheng-Fu , Chang Sheng-Po , Chang Shoou-Jinn , Lin Ray-Ming , Wu Hsin-Hung , Hsu Wen-Ching
Published: July 2012

The optical and electrical characteristics of InGaN‐based blue light‐emitting diodes (LEDs) grown on patterned sapphire substrates (PSSs) with different pattern heights and on planar sapphire by atmospheric‐pressure metal‐organic chemical vapor deposition were investigated. Compared with planar sapphire, it was found that the LED electroluminescence intensity is significantly enhanced on PSSs with pattern heights of 0.5 (21%), 1.1 (57%), 1.5 (81%), and 1.9 (91%) μm at an injected current of 20 mA. The increased light intensity exhibits the same trend in a TracePro simulation. In addition, it was also found that the level of leakage current depends on the density of V‐shape defects, which were measured by scanning electron microscopy.
Higher‐Harmonic Generation Analysis in Complex Waveguides via a Nonlinear Semianalytical Finite Element Algorithm
Authors: Nucera Claudio , Lanza di Scalea Francesco
Published: July 2012

Propagation of nonlinear guided waves is a very attracting phenomenon for structural health monitoring applications that has received a lot of attention in the last decades. They exhibit very large sensitivity to structural conditions when compared to traditional approaches based on linear wave features. On the other hand, the applicability of this technology is still limited because of the lack of a solid understanding of the complex phenomena involved when dealing with real structures. In fact the mathematical framework governing the nonlinear guided wave propagation becomes extremely challenging in the case of waveguides that are complex in either materials (damping, anisotropy, heterogeneous, etc.) or geometry (multilayers, geometric periodicity, etc.). The present work focuses on the analysis of nonlinear second‐harmonic generation in complex waveguides by extending the classical Semianalytical Finite Element formulation to the nonlinear regime, and implementing it into a powerful commercial Finite Element package. Results are presented for the following cases: a railroad track and a viscoelastic plate. For these case‐studies optimum combinations of primary wave modes and resonant double‐harmonic nonlinear wave modes are identified. Knowledge of such combinations is critical to the implementation of structural monitoring systems for these structures based on higher‐harmonic wave generation.
Tocotrienol Supplementation Improves Late-Phase Fracture Healing Compared to Alpha-Tocopherol in a Rat Model of Postmenopausal Osteoporosis: A Biomechanical Evaluation
Authors: Mohamad Sharlina , Shuid Ahmad Nazrun , Mokhtar Sabarul Afian , Abdullah Shahrum , Soelaiman Ima Nirwana
Published: July 2012

This study investigated the effects ofα-tocopherol and palm oil tocotrienol supplementations on bone fracture healing in postmenopausal osteoporosis rats. 32 female Sprague-Dawley rats were divided into four groups. The first group was sham operated (SO), while the others were ovariectomised. After 2 months, the right femora were fractured under anesthesia and fixed with K-wire. The SO and ovariectomised-control rats (OVXC) were given olive oil (vehicle), while both the alpha-tocopherol (ATF) and tocotrienol-enriched fraction (TEF) groups were given alpha-tocopherol and tocotrienol-enriched fraction, respectively, at the dose of 60 mg/kg via oral gavages 6 days per week for 8 weeks. The rats were then euthanized and the femora dissected out for bone biomechanical testing to assess their strength. The callous of the TEF group had significantly higher stress parameter than the SO and OVXC groups. Only the SO group showed significantly higher strain parameter compared to the other treatment groups. The load parameter of the OVXC and ATF groups was significantly lower than the SO group. There was no significant difference in the Young’s modulus between the groups. In conclusion, tocotrienol is better thanα-tocopherol in improving the biomechanical properties of the fracture callous in postmenopausal osteoporosis rat model.
Global Solutions to the Spherically Symmetric Compressible Navier‐Stokes Equations with Density‐Dependent Viscosity
Authors: Lian Ruxu , Huang Lan , Liu Jian
Published: July 2012

We consider the exterior problem and the initial boundary value problem for the spherically symmetric isentropic compressible Navier‐Stokes equations with density‐dependent viscosity coefficient in this paper. For regular initial density, we show that there exists a unique global strong solution to the exterior problem or the initial boundary value problem, respectively. In particular, the strong solution tends to the equilibrium state as t → +∞.
Preparation of SiO2-Capped Sr2MgSi2O7:Eu,Dy Nanoparticles with Laser Ablation in Liquid
Authors: Ishizaki Mika , Katagiri Takao , Sasagawa Takao , Kitamoto Yoshitaka , Odawara Osamu , Wada Hiroyuki
Published: July 2012

The effect of SiO2capping on the optical properties of nanoparticles was investigated. The photoluminescence (PL) intensity was successfully improved by SiO2-capping. Sr2MgSi2O7:Eu,Dy nanoparticles were prepared by laser ablation in liquid. The SiO2capping was performed using the Stöber method with ultrasonication. The TEM images indicated that the Sr2MgSi2O7:Eu,Dy nanocrystal was capped with amorphous SiO2, and the shape of the completely capped nanoparticle was an elliptical nanorod, which aggregated after a long SiO2capping reaction time. The peak wavelength and the shape of the PL spectra were not changed by the pelletization and the laser ablation in liquid. The PL intensity of SiO2capped nanoparticles was significantly increased. Nonradiative relaxation via surface defects and energy transfer to water molecules decrease the PL intensity. These phenomena accelerate in the case of nanoparticles. SiO2capping would prevent these phenomena and improve the optical properties of nanoparticles. The combination of laser ablation in liquid and the chemical reaction is important to expand the applications of this method in various research fields.
An Insight into the Sialomes of Bloodsucking Heteroptera
Authors: Ribeiro José M. C. , Assumpção Teresa C. , Francischetti Ivo M. B.
Published: July 2012

Saliva of bloodsucking arthropods contains dozens or hundreds of proteins that affect their hosts' mechanisms against blood loss (hemostasis) and inflammation. Because acquisition of the hematophagous habit evolved independently in several arthropod orders and at least twice within the true bugs, there is a convergent evolutionary scenario that creates a different salivary potion for each organism evolving independently to hematophagy. Additionally, the immune pressure posed by their hosts creates additional evolutionary pressure on the genes coding for salivary proteins, including gene obsolescence, which opens the niche for coopting new genes (exaptation). In the past 10 years, several salivary transcriptomes from bloodsucking Heteroptera and one from a seed-feeding Pentatomorpha were produced, allowing insight into the salivary potion of these organisms and the evolutionary pathway to the blood-feeding mode.
Attacks on One Designated Verifier Proxy Signature Scheme
Authors: Kang Baoyuan
Published: July 2012

In a designated verifier proxy signature scheme, there are three participants, namely, the original signer, the proxy signer, and the designated verifier. The original signer delegates his or her signing right to the proxy signer, then the proxy signer can generate valid signature on behalf of the original signer. But only the designated verifier can verify the proxy signature. Several designated verifier proxy signature schemes have been proposed. However, most of them were proven secure in the random oracle model, which has received a lot of criticism since the security proofs in the random oracle model are not sound with respect to the standard model. Recently, by employing Water′s hashing technique, Yu et al. proposed a new construction of designated verifier proxy signature. They claimed that the new construction is the first designated verifier proxy signature, whose security does not rely on the random oracles. But, in this paper, we will show some attacks on Yu et al.′s scheme. So, their scheme is not secure.
Degenerate‐Generalized Likelihood Ratio Test for One‐Sided Composite Hypotheses
Authors: Xiang Dongdong , Pu Xiaolong , Wang Lei , Li Yan
Published: July 2012

We propose the degenerate‐generalized likelihood ratio test (DGLRT) for one‐sided composite hypotheses in cases of independent and dependent observations. The theoretical results show that the DGLRT has controlled error probabilities and stops sampling with probability 1 under some regularity conditions. Moreover, its stopping boundaries are constants and can be easily determined using the provided searching algorithm. According to the simulation studies, the DGLRT has less overall expected sample sizes and less relative mean index (RMI) values in comparison with the sequential probability ratio test (SPRT) and double sequential probability ratio test (2‐SPRT). To illustrate the application of it, a real manufacturing data are analyzed.
In SilicoandIn VitroComparison of HIV-1 Subtypes B and CRF02_AG Integrases Susceptibility to Integrase Strand Transfer Inhibitors
Authors: Ni Xiaoju , Abdel-Azeim Safwat , Laine Elodie , Arora Rohit , Osemwota Osamuede , Marcelin Anne-Geneviève , Calvez Vincent , Mouscadet Jean-François , Tchertanov Luba
Published: July 2012

Most antiretroviral medical treatments were developed and tested principally on HIV-1 B nonrecombinant strain, which represents less than 10% of the worldwide HIV-1-infected population. HIV-1 circulating recombinant form CRF02_AG is prevalent in West Africa and is becoming more frequent in other countries. Previous studies suggested that the HIV-1 polymorphisms might be associated to variable susceptibility to antiretrovirals. This study is pointed to compare the susceptibility to integrase (IN) inhibitors of HIV-1 subtype CRF02_AG IN respectively to HIV-1 B. Structural models of B and CRF02_AG HIV-1 INs as unbound enzymes and in complex with the DNA substrate were built by homology modeling. IN inhibitors—raltegravir (RAL), elvitegravir (ELV) and L731,988—were docked onto the models, and their binding affinity for both HIV-1 B and CRF02_AG INs was compared. CRF02_AG INs were cloned and expressed from plasma of integrase strand transfer inhibitor (INSTI)-naïve infected patients. Ourin silicoandin vitrostudies showed that the sequence variations between the INs of CRF02_AG and B strains did not lead to any notable difference in the structural features of the enzyme and did not impact the susceptibility to the IN inhibitors. The binding modes and affinities of INSTI inhibitors to B and CRF02_AG INs were found to be similar. Although previous studies suggested that several naturally occurring variations of CRF02_AG IN might alter either IN/vDNA interactions or INSTIs binding, our study demonstrate that these variations do affect neither IN activity nor its susceptibility to INSTIs.
A Bayesian Analysis of Spectral ARMA Model
Authors: Bezerra Manoel I. Silvestre , Moala Fernando Antonio , Iano Yuzo
Published: July 2012

Bezerra et al. (2008) proposed a new method, based on Yule‐Walker equations, to estimate the ARMA spectral model. In this paper, a Bayesian approach is developed for this model by using the noninformative prior proposed by Jeffreys (1967). The Bayesian computations, simulation via Markov Monte Carlo (MCMC) is carried out and characteristics of marginal posterior distributions such as Bayes estimator and confidence interval for the parameters of the ARMA model are derived. Both methods are also compared with the traditional least squares and maximum likelihood approaches and a numerical illustration with two examples of the ARMA model is presented to evaluate the performance of the procedures.
Increased Cell-Matrix Adhesion upon Constitutive Activation of Rho Proteins by Cytotoxic Necrotizing Factors fromE. coliandY. pseudotuberculosis
Authors: May Martin , Kolbe Tanja , Wang Tianbang , Schmidt Gudula , Genth Harald
Published: July 2012

Cytotoxic necrotizing factors (CNFs) encompass a class of autotransporter toxins produced by uropathogenicE. coli(CNF1) orY. pseudotuberculosis(CNFy). CNF toxins deamidate and thereby constitutively activate RhoA, Rac1, and Cdc42. In this study, the effects of CNF1 on cell-matrix adhesion are analysed using functional cell-adhesion assays. CNF1 strongly increased cell-matrix binding of suspended Hela cells and decreased the susceptibly of cells to trypsin-induced cell detachment. Increased cell-matrix binding was also observed upon treatment of Hela cells with isomeric CNFy, that specifically deamidates RhoA. Increased cell-matrix binding thus appears to depend on RhoA deamidation. In contrast, increased cell spreading was specifically observed upon CNF1 treatment, suggesting that it rather depended on Rac1/Cdc42 deamidation. Increased cell-matrix adhesion is further presented to result in reduced cell migration of adherent cells. In contrast, migration of suspended cells was not affected upon treatment with CNF1 or CNFy. CNF1 and CNFy thus reduced cell migration specifically under the condition of pre-established cell-matrix adhesion.
Metformin-Associated Lactic Acidosis following Intentional Overdose Successfully Treated with Tris-Hydroxymethyl Aminomethane and Renal Replacement Therapy
Authors: Lam Ngan , Sekhon Gurbir , House Andrew A.
Published: July 2012

A 43-year-old woman was brought to the hospital with severe metabolic acidosis (pH 6.56, bicarbonate 3 mmol/L, and lactate 18.4 mmol/L) and a serum creatinine of 162 μmol/L with a serum potassium of 7.8 mmol/L. A delayed diagnosis of metformin-associated lactic acidosis was made, and she was treated with tris-hydroxymethyl aminomethane (THAM) and renal replacement therapy (RRT). Following a complete recovery, she admitted to ingesting 180 tablets (90 grams) of metformin. Her peak serum metformin concentration was 170 μg/mL (therapeutic range 1-2 μg/mL). Our case demonstrates an intentional metformin overdose resulting in lactic acidosis in a nondiabetic patient who was successfully treated with THAM and RRT.
Index of CD34+ Cells and Mononuclear Cells in the Bone Marrow of Spinal Cord Injury Patients of Different Age Groups: A Comparative Analysis
Authors: Dedeepiya Vidyasagar Devaprasad , Rao Yegneswara Yellury , Jayakrishnan Gosalakkal A. , Parthiban Jutty K. B. C. , Baskar Subramani , Manjunath Sadananda Rao , Senthilkumar Rajappa , Abraham Samuel J. K.
Published: July 2012

Introduction. Recent evidence of safety and efficacy of Bone Marrow Mononuclear Cells (BMMNC) in spinal cord injury makes the Bone Marrow (BM) CD34+ percentage and the BMMNC count gain significance. The indices of BM that change with body mass index and aging in general population have been reported but seldom in Spinal Cord Injury (SCI) victims, whose parameters of relevance differ from general population. Herein, we report the indices of BMMNC in SCI victims. Materials and Methods. BMMNCs of 332 SCI patients were isolated under GMP protocols. Cell count by Trypan blue method and CD34+ cells by flow cytometry were documented and analysed across ages and gender. Results. The average BMMNC per ml in the age groups 0–20, 21–40, 41–60, and 61–80 years were 4.71, 4.03, 3.67, and 3.02 million and the CD34+ were 1.05%, 1.04%, 0.94%, and 0.93% respectively. The decline in CD34+ was sharp between 20–40 and 40–60 age groups. Females of reproductive age group had lesser CD34+. Conclusion. The BMMNC and CD34+ percentages decline with aging in SCI victims. Their lower values in females during reproductive age should be analysed for relevance to hormonal influence. This study offers reference values of BMMNC and CD34+ of SCI victims for successful clinical application.
Multithreshold Segmentation Based on Artificial Immune Systems
Authors: Cuevas Erik , Osuna-Enciso Valentin , Zaldivar Daniel , Pérez-Cisneros Marco , Sossa Humberto
Published: July 2012

Bio‐inspired computing has lately demonstrated its usefulness with remarkable contributions to shape detection, optimization, and classification in pattern recognition. Similarly, multithreshold selection has become a critical step for image analysis and computer vision sparking considerable efforts to design an optimal multi‐threshold estimator. This paper presents an algorithm for multi‐threshold segmentation which is based on the artificial immune systems(AIS) technique, also known as theclonal selection algorithm (CSA). It follows the clonal selection principle (CSP) from the human immune system which basically generates a response according to the relationship between antigens (Ag), that is, patterns to be recognized and antibodies (Ab), that is, possible solutions. In our approach, the 1D histogram of one image is approximated through a Gaussian mixture model whose parameters are calculated through CSA. Each Gaussian function represents a pixel class and therefore a thresholding point. Unlike the expectation‐maximization (EM) algorithm, the CSA‐based method shows a fast convergence and a low sensitivity to initial conditions. Remarkably, it also improves complex time‐consuming computations commonly required by gradient‐based methods. Experimental evidence demonstrates a successful automatic multi‐threshold selection based on CSA, comparing its performance to the aforementioned well‐known algorithms.
Markers of Sleep-Disordered Breathing and Prediabetes in US Adults
Authors: Alshaarawy Omayma , Teppala Srinivas , Shankar Anoop
Published: July 2012

Background. Prediabetes is a preclinical stage in the hyperglycemia continuum where subjects are at increased risk of developing diabetes. Several studies reported a positive association between markers of sleep-disordered breathing (SDB) and diabetes. However, few studies investigated the relationship between SDB markers and prediabetes.Methods. We examined 5,685 participants ≥20 years from the National Health and Nutrition Examination Survey (NHANES) 2005–2008. The exposure of interest was SDB markers including sleep duration, snoring, snorting, and daytime sleepiness. The outcome was prediabetes (n=2058), among subjects free of diabetes.Results. SDB markers were associated with prediabetes. Compared to those without any sleep disturbance, the multivariable odds ratio (OR) (95% confidence interval (CI)) of prediabetes among those with three or more SDB markers was 1.69 (1.28–2.22). In subgroup analyses, the association between SDB markers and prediabetes was stronger among women (OR (95% CI) = 2.09 (1.36–3.23) when compared to men (1.52 (1.00–2.35)) and was present among non-Hispanic whites (2.66 (1.92–3.69)) and Mexican Americans (1.99 (1.13–3.48)), but not among non-Hispanic blacks (1.10 (0.70–1.73)).Conclusion. SDB markers were associated with prediabetes. This association was stronger in women and was present mainly in non-Hispanic whites and Mexican Americans.
Effects of Rosiglitazone with Insulin Combination Therapy on Oxidative Stress and Lipid Profile in Left Ventricular Muscles of Diabetic Rats
Authors: Kavak Servet , Ayaz Lokman , Emre Mustafa
Published: July 2012

Purpose. In this study, we tested the hypothesis that rosiglitazone (RSG) with insulin is able to quench oxidative stress initiated by high glucose through prevention of NAD(P)H oxidase activation.Methods and Materials. Male albino Wistar rats were randomly divided into an untreated control group (C), a diabetic group (D) that was treated with a single intraperitoneal injection of streptozotocin (45 mgkg−1), and rosiglitazone group that was treated with RSG twice daily by gavage and insulin once daily by subcutaneous injection (group B). HbA1c and blood glucose levels in the circulation and malondialdehyde and 3-nitrotyrosine levels in left ventricular muscle were measured.Result. Treatment of D rats with group B resulted in a time-dependent decrease in blood glucose. We found that the lipid profile and HbA1c levels in group B reached the control group D rat values at the end of the treatment period. There was an increase in 3-nitrotyrosine levels in group D compared to group C. Malondialdehyde and 3-nitrotyrosine levels were found to be decreased in group B compared to group D(P<0.05).Conclusion. Our data suggests that the treatment of diabetic rats with group B for 8 weeks may decrease the oxidative/nitrosative stress in left ventricular tissue of rats. Thus, in diabetes-related vascular diseases, group B treatment may be cardioprotective.
Structural Behavior and Design of Barrier-Overhang Connection in Concrete Bridge Superstructures Using AASHTO LRFD Method
Authors: Chang Byungik , Mirtalaei Kamal , Lee Seungyeol , Leitch Kenneth
Published: July 2012

The U.S. Departments of Transportation adopted the AASHTO LRFD Bridge Design Specifications during the year 2007, which is mandated by AASHTO and FHWA. The application of LRFD specification initiated numerous research works in this field. This investigation addresses the LRFD and Standard design methodologies of concrete deck slab, deck overhang, barrier and combined barrier-bridge overhang. The purpose of this study is to propose a simplified manual design approach for the barrier-deck overhang in concrete bridges. For concrete deck slab overhang and barrier, application ofNational Cooperative Highway Research Programcrash test is reviewed. The failure mechanism, design philosophy and load cases including extreme event limit states for barrier and overhang are discussed. The overhang design for the combined effect of bending moment and axial tension is probably the most important part of the design process. The overhang might be a critical design point of the deck with significantly higher amount of reinforcement. The design process becomes complicated due to combined force effect, LRFD crash test level requirement and the existence of several load combinations. Using this program, different LRFD load combinations are plotted together with the interaction diagram and the design is validated.
Model-Corrected Microwave Imaging through Periodic Wall Structures
Authors: Chang Paul C. , Burkholder Robert J. , Volakis John L.
Published: July 2012

A model-based imaging framework is applied to correct the target distortion seen in microwave imaging through a periodic wall structure. In addition to propagation delays caused by the wall, it is shown that the structural periodicity induces high-order space harmonics leading to other ghost artifacts in the through-wall image. To overcome these distortions, the periodic layer Green’s function is incorporated into the forward model. A linear back-projection solution and a nonlinear minimization solution are applied to solve the inverse problem. The model-based back-projection image corrects the distortion and has higher resolution compared with free space due to the inclusion of multipath propagation through the periodic wall, but considerable sidelobe clutter is present. The nonlinear solution not only corrects target distortion without clutter but also reduces the solution to a sparse form.
Correlation of LINE-1 Methylation Levels in Patient-Matched Buffy Coat, Serum, Buccal Cell, and Bladder Tumor Tissue DNA Samples
Authors: van Bemmel Dana , Lenz Petra , Liao Linda M. , Baris Dalsu , Sternberg Lawrence R. , Warner Andrew , Johnson Alison , Jones Michael , Kida Masatoshi , Schwenn Molly , Schned Alan R. , Silverman Debra T. , Rothman Nathaniel , Moore Lee E.
Published: July 2012

Background: Evidence suggests that global methylation levels in blood cell DNA may be a biomarker for cancer risk. To date, most studies have used genomic DNA isolated from blood or urine as a surrogate marker of global DNA methylation levels in bladder tumor tissue.

Methods: A subset of 50 bladder cancer cases was selected from the New England Bladder Cancer Case–Control Study. Genomic DNA was isolated from buffy coat, buccal cells, serum, and formalin-fixed, paraffin-embedded tissue for each participant. DNA methylation at four CpG sites within the long interspersed nucleotide element (LINE-1) repetitive element was quantified using pyrosequencing and expressed as a mean methylation level across sites.

Results: Overall, the mean percent (%) LINE-1 5-methylcytosine (%5MeC) level was highest in serum (80.47% ± 1.44%) and lowest in bladder tumor DNA (61.36% ± 12.74%) and levels varied significantly across tissue types (P = 0.001). An inverse association between LINE-1 mean %5MeC and tumor stage (P = 0.001) and grade (P = 0.002) was observed. A moderate correlation between patient-matched serum and buffy coat DNA LINE-1 %5MeC levels was found (r = 0.32, P = 0.03) but levels were uncorrelated among other matched genomic DNA samples.

Conclusions: The mean promoter LINE-1 %5MeC measurements were correlated between buffy coat and serum DNA samples. No correlation was observed between genomic DNA sources and tumor tissues; however a significant inverse association between tumor percent LINE-1 methylation and tumor stage/grade was found.

Impact:LINE-1 methylation measured in case blood DNA did not reflect that observed in bladder tumor tissue but may represent other factors associated with carcinogenesis. Cancer Epidemiol Biomarkers Prev; 21(7); 1143–8. ©2012 AACR.
Expression of Kallikrein-Related Peptidase 7 Predicts Poor Prognosis in Patients with Unresectable Pancreatic Ductal Adenocarcinoma
Authors: Iakovlev Vladimir , Siegel Eric R. , Tsao Ming-Sound , Haun Randy S.
Published: July 2012

Background: Kallikrein-related peptidase 7 (KLK7) is overexpressed in pancreatic ductal adenocarcinomas (PDAC). The aims of this study were to examine the expression of KLK7 during progression of pancreatic intraepithelial neoplasia (PanIN) to invasive PDAC and to assess its prognostic significance for PDAC.

Methods: Immunohistochemistry was used to assess KLK7 expression using a tissue microarray (TMA) and full sections of pancreatic tissue containing normal tissue, PanIN, and invasive adenocarcinoma, and the association between KLK7 expression and prognosis was examined by a population-based pancreatic cancer TMA.

Results: Normal pancreatic epithelium was negative for KLK7 in either TMAs or full sections. Analysis by TMAs showed that 91% of cases showed KLK7 positivity in the adenocarcinoma component, which was significantly higher than PanIN 2/3. In full tissue sections of PDAC, KLK7 expression was detected in less than 1% of cells among PanIN 1A lesions, and increased with grade among PanIN 1B and PanIN2/3 lesions before reaching 69% in the invasive PDAC. In patients with unresected PDAC, KLK7 positivity was significantly associated with shorter overall survival.

Conclusions: Aberrant KLK7 expression starts in intermediate-to-late stages of PanIN progression, and KLK7-positive staining is associated with almost a three-fold increase in mortality rate of patients with unresected PDAC.

Impact: The association of KLK7 expression and poor outcome of patients with unresectable PDAC suggests that inhibiting either KLK7 expression and/or activity could be a therapeutic strategy. Because the vast majority of patients present with unresectable disease, such an intervention could have a significant impact upon the overall survival of this patient population. Cancer Epidemiol Biomarkers Prev; 21(7); 1135–42. ©2012 AACR.
Cancer Prevention and Screening Practices of Siblings of Childhood Cancer Survivors: A Report from the Childhood Cancer Survivor Study
Authors: Buchbinder David , Mertens Ann C. , Zeltzer Lonnie K. , Leisenring Wendy , Goodman Pam , Lown E. Anne , Alderfer Melissa A. , Recklitis Christopher , Oeffinger Kevin , Armstrong Gregory T. , Hudson Melissa , Robison Leslie L. , Casillas Jacqueline
Published: July 2012

Background: To compare the skin and breast/cervical cancer prevention/screening practices of adult siblings of childhood cancer survivors with controls and to identify modifying factors for these practices.

Methods: Cross-sectional, self-report data from 2,588 adult siblings of 5+ year survivors of childhood cancer were analyzed to assess cancer prevention/screening practices. Two age, sex, and race/ethnicity-matched samples (N = 5,915 and N = 37,789) of the Behavioral Risk Factor Surveillance System participants served as the comparison populations. Sociodemographic and cancer-related data were explored as modifying factors for sibling cancer prevention/screening practices through multivariable logistic regression.

Results: Compared with controls, siblings were more likely to practice skin cancer prevention behaviors: use of protective clothing [OR, 2.85; 95% confidence interval (CI), 2.39–3.39], use of shade (OR, 2.11; 95% CI, 1.88–2.36), use of sunscreen (OR, 1.27; 95% CI, 1.14–1.40), and wearing a hat (OR, 1.77; 95% CI, 1.58–1.98). No differences were noted for breast/cervical cancer screening including mammography and Pap testing. Having less than a high school education and lack of health insurance were associated with diminished cancer prevention/screening behaviors. Survivor diagnosis, treatment intensity, adverse health, chronic health conditions, and second cancers were not associated with sibling cancer prevention/screening behaviors.

Conclusions: Siblings of cancer survivors report greater skin cancer prevention practices when compared with controls; however, no differences were noted for breast/cervical cancer screening practices. Access to care and lack of education may be associated with decreased cancer prevention/screening behaviors. Interventions are needed to address these barriers.

Impact: Research should be directed at understanding the impact of the cancer experience on sibling health behaviors. Cancer Epidemiol Biomarkers Prev; 21(7); 1078–88. ©2012 AACR.
Rotating Night Shift Work and Mammographic Density
Authors: Peplonska Beata , Bukowska Agnieszka , Sobala Wojciech , Reszka Edyta , Gromadzinska Jolanta , Wasowicz Wojciech , Lie Jenny Anne , Kjuus Helge , Ursin Giske
Published: July 2012

Background: An increased risk of breast cancer has been observed in night shift workers. Exposure to artificial light at night and disruption of the endogenous circadian rhythm with suppression of the melatonin synthesis have been suggested mechanisms. We investigated the hypothesis that rotating night shift work is associated with mammographic density.

Methods: We conducted a cross-sectional study on the association between rotating night shift work characteristics, 6-sulfatoxymelatonin (MT6s) creatinine adjusted in a spot morning urine sample, and a computer-assisted measure of mammographic density in 640 nurses and midwives ages 40 to 60 years. The associations were evaluated using regression models adjusted for age, body mass index, menopausal status, age at menopause, age at menarche, smoking, and the calendar season of the year when mammography was conducted.

Results: The adjusted means of percentage of mammographic density and absolute density were slightly higher among women working rotating night shifts but not statistically significant [percentage of mammographic density = 23.6%, 95% confidence interval (CI), 21.9%–25.4% vs. 22.5%, 95% CI, 20.8%–24.3%; absolute density = 23.9 cm2, 95% CI, 21.4–26.4 cm2 vs. 21.8 cm2, 95% CI, 19.4–24.3 cm2 in rotating night shift and day shift nurses, respectively). There were no significant associations between the current or cumulative rotating night shift work exposure metrics and mammographic density. No association was observed between morning MT6s and mammographic density.

Conclusions: The hypothesis on the link between rotating night shift work, melatonin synthesis disruption, and mammographic density is not supported by the results of the present study.

Impact: It is unlikely that the development of breast cancer in nurses working rotating night shifts is mediated by an increase in mammographic density. Cancer Epidemiol Biomarkers Prev; 21(7); 1028–37. ©2012 AACR.
Reliability of Serum Biomarkers of Inflammation from Repeated Measures in Healthy Individuals
Authors: Navarro Sandi L. , Brasky Theodore M. , Schwarz Yvonne , Song Xiaoling , Wang C.Y. , Kristal Alan R. , Kratz Mario , White Emily , Lampe Johanna W.
Published: July 2012

Background: Biomarkers of low-grade systemic inflammation are used to study the associations of inflammation with chronic diseases, including cancer. However, relatively little is known about the intraindividual variability of most of these measures.

Methods: Fasting serum samples, collected at baseline and the end of ≥3-week washout periods in a four-diet crossover feeding trial, were used to measure the inflammatory markers high sensitivity C-reactive protein (hsCRP), interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-8, and soluble TNF receptor (sTNFR) I and II. Participants included 62 men and women for analyses of IL-6 and CRP and 56 for analyses of IL-8, TNF-α, and sTNFRs, aged 20 to 40, who were free of factors known to influence inflammation, for example, chronic disease, medication use, heavy alcohol use, smoking, and obesity (body mass index >30 kg/m2). Intraclass correlations (ICC) were estimated using random effects ANOVA, across all four time points (∼6 weeks apart).

Results: ICCs for TNF-α and sTNFR I and II were very high: ICC = 0.92 [95% confidence interval (CI), 0.89–0.96], 0.92 (95% CI, 0.88–0.95), and 0.90 (95% CI, 0.85–0.94), respectively. ICCs for IL-8 and hsCRP were 0.73 (95% CI, 0.63–0.83) and 0.62 (95% CI, 0.49–0.75), respectively. The ICC for IL-6 was considerably lower, ICC = 0.48 (95% CI, 0.36–0.62). Three measures of IL-6 would be needed to achieve a reliability coefficient (Cronbach α) of 0.75.

Conclusions: With the exception of IL-6, reliability of all inflammatory markers in our panel was high.

Impact: This suggests that a single measure accurately captures the short-term (e.g., 4–6 months) variability within an individual. Cancer Epidemiol Biomarkers Prev; 21(7); 1167–70. ©2012 AACR.
Circadian Disruption, Sleep Loss, and Prostate Cancer Risk: A Systematic Review of Epidemiologic Studies
Authors: Sigurdardottir Lara G. , Valdimarsdottir Unnur A. , Fall Katja , Rider Jennifer R. , Lockley Steven W. , Schernhammer Eva , Mucci Lorelei A.
Published: July 2012

Disruption of the circadian system has been hypothesized to increase cancer risk, either because of direct disruption of the molecular machinery generating circadian rhythms or because of disruption of parameters controlled by the clock such as melatonin levels or sleep duration. This hypothesis has been studied in hormone-dependent cancers among women, but data are sparse about potential effects of circadian disruption on the risk of prostate cancer. This review systematically examines available data evaluating the effects of light at night, sleep patterns, and night shift work on prostate cancer risk. Cancer Epidemiol Biomarkers Prev; 21(7); 1002–11. ©2012 AACR.