bluuebunny/crossref_metadata_2025 huggingface dataset:
Interference Mitigation through Successive Cancellation in Heterogeneous Networks
Authors: Sahin Onur , Li Jialing , Lu Enoch , Li Yingxue , Pietraski Philip J.
Published: March 2013

We present a practical interference management scheme for heterogeneous networks (HetNets). The underlying ideas are based on (i) Han-Kobayashi-type message splitting (MS) where the receivers decode and cancel “part” of the interference which is accordingly optimized by the transmitters to ensure decoding and (ii) opportunistic interference cancellation (OIC) where the interfering transmitters act independently of the receivers that employ interference cancellation. We develop a novel transmission and reception scheme, called joint MS and OIC (MS-OIC), that engages both MS and OIC to account for a practical HetNet system with multiple macrocells and femtocells. The MS component includes a precoder design that judiciously maximizes the weighted sum throughput via the enabling of interference cancellation. A system design along with a novel scheduler that facilitates MS-OIC in a general HetNet system is also developed. System level simulations for a general HetNet system are presented, and the proposed MS-OIC scheme is compared with benchmark schemes such as Coordinated Beamforming (CBF) and joint CBF and Almost Blank Subframes (CBF-ABS). It is observed that the proposed MS-OIC scheme improves the macrocell throughput substantially, balances the achievable rates between the macrocell and femtocell users, and provides significant outage performance improvement in the system.
A Multipath Routing Approach for Secure and Reliable Data Delivery in Wireless Sensor Networks
Authors: Alwan Hind , Agarwal Anjali
Published: March 2013

The severe resource constraints and challenging deployment environments of wireless sensor networks (WSNs) pose challenges for the security and reliability of data transmission for these networks. In this paper, we present and evaluate a secure and reliable routing mechanism offering different levels of security in an energy-efficient way for WSNs. Our approach uses node-disjoint routing and the selection mechanism of these paths depends on different application requirements in terms of security. The original data message is split into packets that are coded using Reed-Solomon (RS) codes and, to provide diverse levels of security, different number of fragments is encrypted related to the requested security level before being transmitted along independent node-disjoint paths. This technique makes encryption feasible for energy-constrained and delay-sensitive applications while still maintaining a robust security protection. We describe how to find the secure multipath, the number of these paths, and how to allocate fragments on each path seeking to enhance security and improve data reliability. Extensive analysis and performance evaluation show that data transmission security and reliability can be enhanced while respecting the resource constraints of WSNs.
On Fixed Point Theory of Monotone Mappings with Respect to a Partial Order Introduced by a Vector Functional in Cone Metric Spaces
Authors: Li Zhilong , Jiang Shujun
Published: March 2013

We presented some maximal and minimal fixed point theorems of set-valued monotone mappings with respect to a partial order introduced by a vector functional in cone metric spaces. In addition, we proved not only the existence of maximal and minimal fixed points but also the existence of the largest and the least fixed points of single-valued increasing mappings. It is worth mentioning that the results on single-valued mappings in this paper are still new even in the case of metric spaces and hence they indeed improve the recent results.
Mitral Valve Regurgitation: A Severe Complication following Left Ventricular Biopsy 15 Years after Heart Transplantation
Authors: Vollroth Marcel , Seeburger Joerg , Kiefer Philipp , Garbade Jens , Mohr Friedrich W. , Barten Markus J.
Published: March 2013

A 71-year-old male patient underwent orthotopic heart transplantation in 1995. Due to left heart catheterization 15 years later, biopsy from the left ventricular apex was performed for rejection screening. Two days later, echocardiography revealed severe mitral valve regurgitation requiring mitral valve replacement. This is a very rare case showing that left heart biopsy may lead to severe hemodynamic complications with the need for surgical intervention.
Two-Dimensional Stress Intensity Factor Analysis of Cracks in Anisotropic Bimaterial
Authors: Tu Chia-Huei , Dong Jia-Jyun , Chen Chao-Shi , Ke Chien-Chung , Jhan Jyun-Yong , Yu Hsien Jui
Published: March 2013

This paper presents a 2D numerical technique based on the boundary element method (BEM) for the analysis of linear elastic fracture mechanics (LEFM) problems on stress intensity factors (SIFs) involving anisotropic bimaterials. The most outstanding feature of this analysis is that it is a singledomain method, yet it is very accurate, efficient, and versatile (i.e., the material properties of the medium can be anisotropic as well as isotropic). A computer program using the BEM formula translation (FORTRAN 90) code was developed to effectively calculate the stress intensity factors (SIFs) in an anisotropic bi-material. This BEM program has been verified and showed good accuracy compared with the previous studies. Numerical examples of stress intensity factor calculation for a straight crack with various locations in both finite and infinite bimaterials are presented. It was found that very accurate results can be obtained using the proposed method, even with relatively simple discretization. The results of the numerical analysis also show that material anisotropy can greatly affect the stress intensity factor.
A New Similarity Measure of Generalized Trapezoidal Fuzzy Numbers and Its Application on Rotor Fault Diagnosis
Authors: Zuo Xin , Wang Lijun , Yue Yuanlong
Published: March 2013

Fault diagnosis technology plays a vital role in the variety of critical engineering applications. Fuzzy approach is widely employed to cope with decision-making problems because it is in the simplest and most used form. This paper proposed a new similarity measure of generalized trapezoidal fuzzy numbers used for fault diagnosis. The presented similarity measure combines concepts of the geometric distance, the center of gravity point, the perimeter, and the area of the generalized trapezoidal fuzzy numbers for calculating the degree of similarity between generalized trapezoidal fuzzy numbers. This method is proposed to deal with both standardized and nonstandardized generalized trapezoidal fuzzy numbers. Some properties of the proposed similarity measure have been proved, and 12 sets of generalized fuzzy numbers have been used to compare the calculation results of the proposed similarity measures with the existing similarity measures. Comparison results indicate that the proposed similarity measure can overcome the drawbacks of existing similarity measures. Finally, a fault diagnosis experiment is carried out in laboratory based on multifunctional flexible rotor experiment bench. Experimental results demonstrate that the proposed similarity measure is more effective than other methods in terms of rotor fault diagnosis.
Hormonal Risk Factors for Breast Cancer and DNA Methylation
Authors: H Nichols , D Sandler , L DeRoo , Z Xu , J Taylor
Published: March 2013

Epigenetic modifications influence gene expression and have been implicated in the development of breast cancer. Few studies have evaluated breast cancer risk factors in relation to DNA methylation. We examined known reproductive and hormonal risk factors for breast cancer and epigenome-wide methylation patterns. Participants included 612 women enrolled in the Sister Study prospective cohort who did not have breast cancer. DNA methylation profiling was performed using an Illumina array at the NIH Center for Inherited Disease (CIDR) on DNA extracted from whole blood. Methylation data was obtained at single CpG site resolution for 27,578 CpG sites covering >14,000 genes across 23 chromosomes. Statistical analyses were performed using normalized methylation residuals from a linear model adjusting for age and experimental variables. Controlling for a false discovery rate of 5% (q < 0.05), 1,452 methylation sites (1,220 in CpG islands) were differentially methylated in postmenopausal women compared to premenopausal women. Average methylation was increased at 1,040 sites and decreased at 412 sites. Gene ontology (GO) analysis suggested enrichment of several biological pathways including lobular involution. Among parous women, only 2 sites (1 CpG island) were differentially methylated among women with older versus younger ages at first birth. A single CpG site demonstrated lower average methylation values among long-term users of postmenopausal hormones compared to short-term users. No further statistically significant differences in methylation patterns (q < 0.05) were observed according to age at menarche, parity, breastfeeding history, or postmenopausal hormone use. These data support the menopausal transition as an influential period for epigenetic modifications; few associations between DNA methylation and other classical reproductive and hormonal breast cancer risk factors were observed.
A Prospective Study of Circulating Adipokine Levels and Risk of Multiple Myeloma
Authors: J Hofmann , L Liao , M Pollak , Y Wang , R Pfeiffer , D Baris , G Andreotti , Q Lan , O Landgren , N Rothman , M Purdue
Published: March 2013

Purpose: Obesity is associated with an increased risk of multiple myeloma (MM), although the biologic mechanisms underlying this association are unclear. We conducted a nested case-control study in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial to evaluate the hypothesis that altered circulating levels of adipokines, polypeptide hormones with pro- and anti-inflammatory properties secreted by adipose tissue, may partly explain the association between obesity and MM. Methods: We investigated whether circulating levels of leptin, total adiponectin, and high-molecular-weight (HMW) adiponectin are associated with MM among 174 cases and 348 controls in PLCO. Two controls were matched to each case on age at baseline, sex, race, date of phlebotomy, time of day of phlebotomy, and study year of specimen collection. Plasma adipokine concentrations were measured by enzyme-linked immunosorbent assay; overall coefficients of variation were ≤8.5%. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using conditional logistic regression. Results: Inverse associations with MM were observed for total adiponectin (highest quartile vs. lowest: OR = 0.49, 95% CI = 0.26–0.93, P-trend = 0.03) and HMW adiponectin (OR = 0.44, 95% CI = 0.23–0.85, P-trend = 0.01). These associations remained after adjusting for body mass index (BMI), stratifying by sex, and restricting to cases diagnosed approximately eight years or more after blood collection. We observed a modest association between BMI and MM (OR per 5 kg/m2 increase = 1.14, 95% CI = 0.94–1.39), which was attenuated by approximately 40% after adjusting for adiponectin. Leptin levels were not associated with MM. Conclusions: These results suggest that higher circulating levels of adiponectin are protective against MM, and that adiponectin may play an important role in obesity-related myelomagenesis. This study is, to our knowledge, the first prospective investigation of circulating adipokines and MM. Our findings are particularly intriguing in light of recent evidence that host-derived adiponectin is tumor-suppressive and a potential novel therapeutic target for MM and associated bone disease.
Aspirin and Colorectal Cancer Incidence and Mortality by CTNNB1 Expression: A Molecular Pathological Epidemiology (MPE) Study
Authors: R Sun , R Nishihara , ZR Qian , AT Chan , S Ogino
Published: March 2013

Purpose: Experimental studies showed that aspirin down-regulates the WNT/CTNNB1 (β-catenin) signaling pathway in colon cancer cells. We investigated whether aspirin use was associated with lower incidence and superior survival in nuclear CTNNB1-positive colorectal cancer. Methods: In two large prospective studies (the Nurses' Health Study and the Health Professionals Follow-up Study), we collected the information on aspirin use every 2 years from 1980 through 2008. We used Cox proportional hazards regression to compute the multivariate hazard ratio for incidence and mortality according to tumor CTNNB1 expression patterns. Results: During 28 years and 3,166,091 person-years of follow-up, we documented 931 incident cases of colorectal cancer with available CTNNB1 expression data. Regular aspirin use was associated with a significantly lower risk of CTNNB1-positive cancer (multivariate HR = 0.65; 95% CI, 0.53–0.80), but not with the risk of CTNNB1-negative cancer (multivariate HR = 0.84; 95% CI, 0.70–1.01). A formal test of heterogeneity of the association according to CTNNB1 expression status did not reach statistical significance (P = 0.07). Regular aspirin use after diagnosis of colorectal cancer was associated with better colorectal cancer-specific survival among CTNNB1-positive tumor patients (multivariate HR = 0.53; 95% CI, 0.30–0.95). In contrast, among CTNNB1-negative tumor patients, post-diagnosis regular aspirin use was not associated with colorectal cancer-specific survival (multivariate HR = 1.06; 95% CI, 0.62–1.83) (P = 0.04 for interaction test between aspirin use and CTNNB1 status). Conclusions: Regular aspirin use was associated with lower incidence of nuclear CTNNB1-positive cancer, and better survival among patients with nuclear CTNNB1-positive cancer. Our molecular pathological epidemiology (MPE) study revealed the anti-tumor mechanism of aspirin, which might prevent cancer incidence and mortality by inhibiting tumor initiation and/or progression in the WNT/CTNNB1-related carcinogenesis pathway.
Human Papillomavirus Vaccine Knowledge and Uptake among Adolescent Boys and Girls in an Appalachian Ohio County
Authors: MP Bhatta , L Phillips , S Frew , J Burns , N Cascarelli
Published: March 2013

Background: Population-based studies of human papillomavirus (HPV) vaccine uptake among both adolescent boys and girls are limited. The purpose of this study was to examine middle and high school student knowledge and behaviors surrounding the HPV vaccine in a rural Appalachian Ohio county. Methods: Five questions regarding the HPV vaccine were added to 2012 Youth Risk Behavior Survey (YRBS) administered in an Ohio Appalachian county. The participants were asked whether or not they had heard of the HPV vaccine; been given the vaccine and, if yes, the number of shots received; and whether their health care provider and/or their parents had discussed the vaccine with them. The voluntary and anonymous survey was completed by a total of 1,300 adolescent boys and girls. Results: Of the 596 and 704 high school students who completed the survey, 51.9% were male and 48.1% were female, and 95% were white. Regarding whether they had ever heard of the HPV vaccine, 49.1%, 29.6%, 21.2% respectively reported ‘yes’, ‘no’, and ‘don't know/not sure’. Girls were more likely to report having heard of the HPV vaccine than boys (56.7% vs. 42.19%; p < 0.001). In all, 19.5% and 24.5% of the participants indicated having their parents and a health care provider respectively having discussed the HPV vaccine with them. Girls were two times as likely to report having a parent discuss the HPV vaccine with them than boys (P < 0.01). They were also almost three times as likely than boys to report a health care provider having discussed the vaccine with them (p < 0.01). Overall, 11.4% boys and 21.3% girls reported having received at least one dose of the vaccine (p < 0.001). The HPV uptake rates among middle and high school boys and girls respectively were 9.2%, 13.2%, 14.4%, and 27.4%. Conclusion: The HPV vaccine knowledge, as well as parental and health care provider communication regarding the HPV vaccine, particularly with the boys, remains low among these rural Appalachian adolescents. The role of these two factors on the HPV vaccine uptake among this adolescent population needs to be further explored.
Differences in Mammographic Density Decline over Time in Breast Cancer Cases and Women at High Risk for Breast Cancer
Authors: ME Work , LL Reimers , AS Quante , KD Crew , A Whiffen , MB Terry
Published: March 2013

Introduction: High absolute breast density and increased breast density over time are strongly associated with breast cancer risk, and breast density generally decreases with increasing age. We examined mammographic density data from members of the Women At Risk High-Risk Registry at Columbia University Medical Center (WAR), a cohort defined as at high risk for breast cancer due to family history of breast cancer, history of lobular carcinoma in situ, and/or benign breast disease, to determine changes in their breast density over time. Methods: Within the WAR cohort of 1598 women, we conducted a nested case-control study of 66 incident cases of invasive breast cancer and 70 women without cancer, matched on age and time between first and second mammogram. For each participant, we collected two mammograms (for the cases, both mammograms occurred before cancer diagnosis), to examine differences in absolute density, percent density, and change in density between cases and controls. The average time between first and second mammogram was 4.6 years for both cases and controls, with a range of between 1 and 15 years. Results: Using linear regression with change in percent density as the outcome, and time between first and second mammogram as the independent variable, we found that among women without breast cancer, density decreased as time between first and second mammogram increased (β = −2.15, p = 0.005). In contrast, there was no overall change in density among the cases associated with time between first and second mammogram (β = 0.69, p = 0.39). In an ANCOVA comparing the slopes of the regression lines, the slopes were significantly different for cases versus controls (p = 0.009). Conclusion: In a cohort of women at high risk for breast cancer, breast density does not decrease as time between mammograms increases, for women who go on to develop breast cancer. For women who do not develop breast cancer, breast density decreases significantly over time.
Breast cancer susceptibility loci in association with age at menarche, age at natural menopause and the reproductive lifespan
Authors: Warren Andersen S , Trentham-Dietz A , Gangnon RE , Hampton JM , Figueroa JD , Skinner HG , Engelman CD , Klein BE , Titus LJ , Egan KM , Newcomb PA
Published: March 2013

Purpose: Genome wide association studies have identified common single nucleotide polymorphisms (SNPs) associated with breast cancer risk. Many of these SNPs have an unknown biologic significance. Hormonal risk factors may mediate the relationships between these loci and breast cancer risk. We explored the relation between breast cancer susceptibility loci and menstrual factors using data from two population-based studies. Methods: In the first dataset, composed of 1328 women ages 20–74 years without a breast cancer diagnosis who participated in an established population-based study conducted in three U.S. states, we used linear regression to assess the associations between 13 previously-identified breast cancer loci with age at menarche, age at natural menopause and the reproductive lifespan. The reproductive lifespan is defined as the time between age at menarche and age at natural menopause, excluding time for pregnancy, oral contraceptive use and lactation. A polygenic risk score created as the sum of the number of risk allele copies in the SNPs was also evaluated for an association with menstrual traits. Significant results were then evaluated in the second dataset comprised of 1353 women ages 43–86 years recruited as part of a cohort study based in Beaver Dam, WI. Results: Polygenic score and 13 loci were not associated with either age at menarche or reproductive lifespan. Two SNPs were associated with age at natural menopause; each increase in the number of copies of the minor allele (A) of rs17468277 (CASP8) was associated with a 1.12 year decrease in age at natural menopause (p = 0.02). The minor allele (G) of SNP rs10941679 (5p12) (p = 0.01) was associated with a 1.01 year increase in age at natural menopause, although these results were not replicated in the follow-up study (p = 0.14 and 0.98, respectively). Conclusions: We did not find evidence to support the hypothesis that breast cancer susceptibility loci are related to menstrual factors.
DiI Labeling of Human Adipose-Derived Stem Cells: Evaluation of DNA Damage, Toxicity and Functional Impairment
Authors: Froelich K. , Steussloff G. , Schmidt K. , Ramos Tirado M. , Technau A. , Scherzed A. , Hackenberg S. , Radeloff A. , Hagen R. , Kleinsasser N.
Published: March 2013

Introduction: Adipose tissue-derived stem cells (ASCs) have become the primary focus of tissue engineering research. To understand their functions and behavior in in vitro and in vivo models, it is mandatory to track the implanted cells and distinguish them from the resident or host cells. A common labeling method is the use of fluorescent dyes, e.g. the lipophilic carbocyanine dye, DiI. This study aimed to analyze potential DNA damage, toxicity and impairment of the functional properties of human ASCs after labeling with DiI. Methods: Cytotoxicity was measured using the MTT assay and DNA damage was determined by means of the comet assay. Potential apoptotic effects were determined using the annexin V-propidium iodide test. Differentiation potential was evaluated by trilineage differentiation procedures in labeled and unlabeled ASCs. Proliferation as well as migration capability was analyzed, and the duration and stability of DiI labeling in ASCs during in vitro expansion was observed over a period of 35 days. Results: DiI labeling did not cause genotoxic effects 15, or 30 min or 24 h after the labeling procedure, and there were no cytotoxic effects until 72 h afterwards. No impairment of proliferation or migration capability or differentiation potential could be determined. However, after 35 days, only 37% of labeled cells could be detected using the fluorescence microscope, which indicates a decrease in staining stability during in vitro expansion. Conclusion: DiI is a convenient method for ASCs labeling which causes no toxic effects and does not impair the proliferation, migration or differentiation potential of ASCs after the labeling procedure.
Evaluation of Surgical Outcome of Penile Augmentation and Lengthening Procedures
Authors: Nabil Nashaat , Hosny Hossam , Kadah Amr , Shamloul Rany
Published: March 2013

Our study included 280 patients complaining of small-sized penis. They were seen in the outpatient clinic of the Andrology Department, Kasr El Aini, Cairo University. Patients were collected from 2002 till 2008 and classified into 4 categories from an etiological point of view. Eleven patients (3.9%) were operated upon according to fine selection criteria; six patients were selected for lengthening procedures, while two patients were selected for increasing girth procedures and three patients for combined operation of lengthening and increasing girth techniques. Seven patients showed subjective satisfaction after lengthening procedures and four patients showed subjective satisfaction after increasing girth techniques. In conclusion, detailed analysis of short penis complaint with a proper diagnosis and patient education are required for accurate management of patients complaining of a short penis.
Should an Appendectomy Be Performed for the Treatment of Amyand's Hernia with Non-Inflamed Vermiform Appendix? A Case Report and Review of the Literature
Authors: Kuru Serdar , Bulgurcu Abdullah , Kismet Kemal , Ertas Ertugrul
Published: March 2013

Background: Presence of vermiform appendix in an inguinal hernia, whether inflamed or not, is called Amyand's hernia. We present a case that was operated on for Amyand's hernia and discuss whether or not an appendectomy should be performed in such a patient, even in the case of a non-inflamed appendix. Case Report: We report a case of Amyand's hernia with non-inflamed appendix, adhering to the inguinal sac wall. A 36-year-old man who was scheduled for elective surgery was referred to our hospital for a large right-side inguinal hernia. During the operation, the appendix was found within the indirect sliding hernia sac. The appendix was non-inflamed and adhered to the inguinal sac wall. The appendix and cecum were freed from adhesions to the sac. Then, appendectomy was performed. The hernioplasty was carried out with synthetic mesh. The postoperative course of the patient was uneventful while pathological examination revealed a normal appendix with lymphoid hyperplasia. The patient had no problems on the postoperative follow-ups after 3 and 6 months. Conclusions: The treatment approach of Amyand's hernia depends on the inflammatory state of the appendix. If the appendix is inflamed, appendectomy is mandatory. If the appendix is normal, appendectomy is controversial. Although there is a general consensus by most authors that a normal appendix in the hernia sac does not require appendectomy because of the risk of infectious complications, it is important to be aware of all clinical settings. The decision to perform an appendectomy and/or to use the mesh technique should always be individualized to the patient.
Selbstbezogenes Unvollständigkeitserleben bei Zwangsstörungen
Authors: Ecker Willi , Kupfer Jochen , Gönner Sascha
Published: March 2013

Hintergrund: Unvollständigkeitserleben wird zunehmend als klinisch relevante Motivdimension der Zwangsstörung diskutiert. Hierbei wird primär der Aspekt des «Nicht-genau-richtig-Erlebens» betont, während selbstbezogenes Unvollständigkeitserleben (SU) als zwangsspezifische Ausprägungsform von Depersonalisationserleben bislang kaum untersucht wurde. Ziel dieser Studie ist es, ein ökonomisches Selbstbeurteilungsinstrument zur Messung der Schwere von SU zu entwickeln. Methodik: 190 Patienten mit einer Zwangsstörung erhielten 24 Items, die inhaltlich SU abbilden, und zusätzlich eine Reihe weiterer Messinstrumente zur Untersuchung der Konstruktvalidität. Ergebnisse: Auf der Basis inhaltlicher und statistischer Überlegungen wurde der Fragebogen zum SU (FSU-12) entwickelt, der mit je 3 Items 4 Dimensionen des SU abbildet (Depersonalisationserleben, Derealisationserleben, Selbsterleben als automatenhaft, Fehlen lebendiger Gefühle). Ein lineares Strukturgleichungsmodell zeigt eine gute Passung der empirischen Daten und der Modellstruktur. Die innere Konsistenz der FSU-12-Gesamtskala und der einzelnen Subskalen ist hervorragend. SU und Nicht-genau-richtig-Erleben liefern voneinander unabhängige Beiträge zur Vorhersage der Schwere von Zwängen und zeigen unterschiedliche Zusammenhänge mit Depersonalisation/Derealisation und zwanghaften Persönlichkeitszügen. Sie stellen also voneinander abgrenzbare, gleichermaßen zwangsrelevante Aspekte von Unvollständigkeitserleben dar. Schlussfolgerung: Der FSU-12 ist ein reliables und valides Screening-Instrument zur Einschätzung des individuellen Ausprägungsgrads von SU bei Zwangsstörungen.
Neurodegeneration in Streptozotocin-Induced Diabetic Rats Is Attenuated by Treatment with Resveratrol
Authors: Jing Yu-Hong , Chen Kuan-Hsing , Kuo Pei-Ching , Pao Chia-Chi , Chen Jan-Kan
Published: March 2013

Aim: Diabetes mellitus-associated hyperglycemia and oxidative stress have been shown to have detrimental effects on the brain and may lead to impairment of cognitive functions. Resveratrol (Rsv), a polyphenolic antioxidant, has been shown to have moderate hypoglycemic and prominent hypolipidemic effects in diabetic rats. In the present study, we examined if Rsv improves the diabetic encephalopathy and explored its possible underlying mechanisms. Methods: Male SD rats were treated with streptozotocin (65 mg/kg), and the diabetic rats were orally fed with Rsv (0.75 mg/kg, every 8 h) or normal saline for 4 weeks. Animals were then sacrificed and the brain tissues (hippocampus) processed for biochemical and histological studies. Results: Neurodegeneration and astrocytic activation were noted in the hippocampus of the diabetic rats. Tumor necrosis factor-α, IL-6 transcripts and nuclear factor-κB expression were increased in the brain. In addition, neuropathic alterations in the hippocampus were evident in diabetic rats, including increased blood vessel permeability and VEGF expression, decreased mitochondrial number and AMP-activated protein kinase activity. In Rsv-treated diabetic rats, the aforementioned abnormalities were all attenuated. Conclusion: These observations suggest that Rsv significantly attenuated neurodegeneration and astrocytic activation in the hippocampus of diabetic rats. Our results suggested that Rsv could potentially be a new therapeutic agent for diabetic encephalopathy and neurodegeneration.
Regional Myocardial Wall Thinning at Multidetector Computed Tomography Correlates to Arrhythmogenic Substrate in Postinfarction Ventricular Tachycardia
Authors: Komatsu Yuki , Cochet Hubert , Jadidi Amir , Sacher Frédéric , Shah Ashok , Derval Nicolas , Scherr Daniel , Pascale Patrizio , Roten Laurent , Denis Arnaud , Ramoul Khaled , Miyazaki Shinsuke , Daly Matthew , Riffaud Matthieu , Sermesant Maxime , Relan Jatin , Ayache Nicholas , Kim Steven , Montaudon Michel , Laurent François , Hocini Mélèze , Haïssaguerre Michel , Jaïs Pierre
Published: March 2013

Background—

A majority of patients undergoing ablation of ventricular tachycardia have implanted devices precluding substrate imaging with delayed-enhancement MRI. Contrast-enhanced multidetector computed tomography (MDCT) can depict myocardial wall thickness with submillimetric resolution. We evaluated the relationship between regional myocardial wall thinning (WT) imaged by MDCT and arrhythmogenic substrate in postinfarction ventricular tachycardia.

Methods and Results—

We studied 13 consecutive postinfarction patients undergoing MDCT before ablation. MDCT data were integrated with high-density 3-dimensional electroanatomic maps acquired during sinus rhythm (endocardium, 509±291 points/map; epicardium, 716±323 points/map). Low-voltage areas (<1.5 mV) and local abnormal ventricular activities (LAVA) during sinus rhythm were assessed with regard to the WT. A significant correlation was found between the areas of WT <5 mm and endocardial low voltage (correlation-
R
=0.82;
P
=0.001), but no such correlation was found in the epicardium. The WT <5 mm area was smaller than the endocardial low-voltage area (54 cm
2
[Q1–Q3, 46–92] versus 71 cm
2
[Q1–Q3, 59–124];
P
=0.001). Among a total of 13 060 electrograms reviewed in the whole study population, 538 LAVA were detected and analyzed. LAVA were located within the WT <5 mm (469/538 [87%]) or at its border (100% within 23 mm). Very late LAVA (>100 ms after QRS complex) were almost exclusively detected within the thinnest area (93% in the WT<3 mm).

Conclusions—

Regional myocardial WT correlates to low-voltage regions and distribution of LAVA critical for the generation and maintenance of postinfarction ventricular tachycardia. The integration of MDCT WT with 3-dimensional electroanatomic maps can help focus mapping and ablation on the culprit regions, even when MRI is precluded by the presence of implanted devices.
Hyobanche thinophila (Orobanchaceae), a new species from the Western Cape of South Africa
Authors: WOLFE ANDREA D.
Published: March 2013

The new species Hyobanche thinophila is described and illustrated. It is distinguished from H. sanguinea by the absence of glandular hairs on the interior surface of the corolla, and differences in the shape and color of the corolla and inflorescence. The interior surface of the H. thinophila corolla is glabrous except for a zone of long multicellular hairs at the level of stamen insertion. Hyobanche sanguinea lacks this character. The new species occurs in dune areas along the coast of Western Cape, South Africa.
Outcome of patients with advanced solitary fibrous tumors: the Centre Léon Bérard experience
Authors: Levard Alice , Derbel Olfa , Méeus Pierre , Ranchère Dominique , Ray-Coquard Isabelle , Blay Jean-Yves , Cassier Philippe A
Published: March 2013

Background

Solitary Fibrous Tumor is a rare type of soft tissue tumor of intermediate malignant potential which may recur or metastasize in 15-20% of cases. Data on the management of patients with advanced SFT is scarce: chemotherapy has been described as ineffective, while recent data suggests that anti-angiogenic therapies may be more efficient.

Methods

We conducted a retrospective study on patients treated for advanced SFT at a single institution: from January 1994 to December 2011, 30 patients were treated in the Centre Léon Bérard for an advanced SFT.

Results

Twenty-three patients received cytotoxic chemotherapy as first-line therapy. Best responses were 2 (9%) partial responses, 13 (57%) stable diseases (SD) and 8 (35%) progressive diseases (PD). Median Progression Free Survival (PFS) was 5.2 (95% CI: 3.2-7.1) months and 9 patients were free of progression at 6 months. Ten patients received an anti-angiogenic treatment (sunitinib or pazopanib) as a 2nd, 3rd or 4th line. Best responses were 5 SD and 5 PD; median PFS was 5.1 months (95% CI 0.7-9.6). Four patients (36%) were progression-free for more than 6 months. Two patients receiving pazopanib were without progression at 6 and 8 months and two patients receiving sunitinib were free of progression at 30 months.

Conclusion

Response rate with standard chemotherapy was low and PFS appear similar between cytotoxic chemotherapy and anti-angiogenic agents.
Insulin and insulin like growth factor II endocytosis and signaling via insulin receptor B
Authors: Giudice Jimena , Barcos Lucia Soledad , Guaimas Francisco F , Penas-Steinhardt Alberto , Giordano Luciana , Jares-Erijman Elizabeth A , Coluccio Leskow Federico
Published: March 2013

Background

Insulin and insulin-like growth factors (IGFs) act on tetrameric tyrosine kinase receptors controlling essential functions including growth, metabolism, reproduction and longevity. The insulin receptor (IR) binds insulin and IGFs with different affinities triggering different cell responses.

Results

We showed that IGF-II induces cell proliferation and gene transcription when IR-B is over-expressed. We combined biotinylated ligands with streptavidin conjugated quantum dots and visible fluorescent proteins to visualize the binding of IGF-II and insulin to IR-B and their ensuing internalization. By confocal microscopy and flow cytometry in living cells, we studied the internalization kinetic through the IR-B of both IGF-II, known to elicit proliferative responses, and insulin, a regulator of metabolism.

Conclusions

IGF-II promotes a faster internalization of IR-B than insulin. We propose that IGF-II differentially activates mitogenic responses through endosomes, while insulin-activated IR-B remains at the plasma membrane. This fact could facilitate the interaction with key effector molecules involved in metabolism regulation.
Interferon block to HIV-1 transduction in macrophages despite SAMHD1 degradation and high deoxynucleoside triphosphates supply
Authors: Dragin Loic , Nguyen Laura Anh , Lahouassa Hichem , Sourisce Adèle , Kim Baek , Ramirez Bertha Cecilia , Margottin-Goguet Florence
Published: March 2013

Background

Interferon-α (IFN-α) is an essential mediator of the antiviral response, which potently inhibits both early and late phases of HIV replication. The SAMHD1 deoxynucleoside triphosphate (dNTP) hydrolase represents the prototype of a new antiviral strategy we referred to as “nucleotide depletion”. SAMHD1 depletes dNTP levels in myeloid cells below those required for optimal synthesis of HIV viral DNA. HIV-2 and its SIVsm and SIVmac close relatives encode a protein termed Vpx, which counteracts SAMHD1. The potentiality of IFN-α to cooperate with nucleotide depletion has been poorly investigated so far. Here we wondered whether IFN-α affects SAMHD1 expression, Vpx-induced SAMHD1 degradation, Vpx-mediated rescue of HIV-1 transduction and the dNTP supply in monocyte-derived macrophages (MDMs).

Results

IFN-α inhibited HIV-1 transduction in monocytes and in MDMs while SAMHD1 expression was not up-regulated. Vpx triggered SAMHD1 degradation in IFN-α treated cells, and weakly restored HIV-1 transduction from the IFN-α block. Vpx helper effect towards HIV-1 transduction was gradually inhibited with increasing doses of IFN-α. dNTP levels were not significantly affected in MDMs and CD4+ primary activated T lymphocytes by IFN-α and, in correlation with SAMHD1 degradation, restoration of dNTP levels by Vpx was efficient in MDMs treated with the cytokine. In contrast, IFN-α inhibited Vpx-mediated SAMHD1 degradation in THP-1 cells, where, accordingly, Vpx could not rescue HIV-1 transduction.

Conclusion

Our results suggest that the early antiviral effect of IFN-α results from a mechanism independent of nucleotide depletion in MDMs. In addition, they indicate that the macrophage-like THP-1 cell line may provide a system to characterize an IFN-α-induced cell response that inhibits Vpx-mediated SAMHD1 degradation.
PolyViNE: policy-based virtual network embedding across multiple domains
Authors: Samuel Fady , Chowdhury Mosharaf , Boutaba Raouf
Published: March 2013

Intra-domain virtual network embedding is a well-studied problem in the network virtualization literature. For most practical purposes, however, virtual networks (VNs) must be provisioned across heterogeneous administrative domains managed by multiple infrastructure providers (InPs).

In this paper, we present PolyViNE, a policy-based inter-domain VN embedding framework that embeds end-to-end VNs in a decentralized manner. PolyViNE introduces a distributed protocol that coordinates the VN embedding process across participating InPs and ensures competitive prices for service providers (SPs), i.e., VN owners, while providing monetary incentives for InPs to participate in the process even under heavy competition. We also present a location-aware VN request forwarding mechanism – basd on a hierarchical addressing scheme (COST) and a location awareness protocol (LAP) – to allow faster embedding. We outline scalability and performance characteristics of PolyViNE through quantitative and qualitative evaluations.
Foundation News
Authors: Blythe Natalie
Published: March 2013

With all of the excitement the glittering lights of Las Vegas brings, attendees of the Foundation's Annual Donor Luncheon, held during SEG's 2012 Annual Meeting, found themselves caught up in the midst of excitement as the Foundation highlighted its 2012 successes and the road traveled since incorporation as a SEG supporting organization in 1987. Tom Smith, chairman of the SEG Foundation Board of Directors, thanked everyone for making possible the important work of the SEG Foundation, and began the event with announcements about major financial donations to key programs. He first revealed that Paradigm Geophysical is the latest company to support the Distinguished Lecture Program, joining others with a five-year commitment of US $250,000 to help bring leading geophysical advances to SEG members around the world. “It is always a great pleasure for us to support our new students and industry training. It's an important cause for us, and we are happy to continue supporting the Foundation,” said Eldad Weiss, chairman and CEO.
Shear-wave high-resolution seismic reflection in Ottawa and Quebec City, Canada
Authors: Pugin André J.-M. , Pullan Susan E. , Hunter James A.
Published: March 2013

Two examples of multicomponent shear (S)-wave, shallow, seismic reflection profiling from urban en-vironments in eastern Canada are presented to examine the benefits of shear-wave reflection data and the latest developments in acquisition methodology, as well as our evolving understanding of the complex nature of seismic-wave propagation. In “soft” soils characterized by low shear-wave velocities, high-resolution shear-wave reflection sections can be obtained, with the highest-resolution data related to horizontal or vertical components of motion. Multicomponent recording provides the capacity to record valuable shear-wave velocity information for earthquake amplification and engi-neering investigations in urban environments.
Pseudo-random sweeps for built-up area seismic surveys
Authors: Scholtz Péter
Published: March 2013

Optimized pseudo-random sequences proved effective, both theoretically and empirically, in increasing data quality while reducing possible damage to buildings by vibratory sources during seismic reflection data acquisition. The linear sweeps commonly used for vibratory measurements can cause resonance in nearby infrastructure; hence, there is a potential for property damage. A pseudo-random sweep signal can be designed to decrease resonance effects and therefore reduce damage thresholds. The sweep sequences produced by simple random number generators, like the ones given by the vibrator manufacturers, have marked disadvantages, such as high correlation noise, large fluctuations in spectral amplitudes, and reduced seismic energy. To overcome some of these problems, an optimization process can be developed to produce pseudo-random sweeps for site-specific conditions. Two strategies are considered for preprocessing: crosscorrelation and deterministic deconvolution. Analysis of examples for an optimum pseudo-random sweep and simple pseudo-random sweep demonstrates that the total seismic energy is increased, while side-lobe energy is decreased and spectral fluctuations are reduced when the pseudo-random sweep is optimized. A limited-scope field test reveals that the peak particle velocity values are lowered substantially, while correlated and deconvolved records generated by the optimized pseudo-random sweep are of similar quality to a linear-sweep record. Application of optimized pseudo-random sweeps has the potential to increase productivity, while maintaining data quality and reducing resonance in surveys of built-up areas.
Imaging of a shallow gas horizon using high-resolution reflection seismic within urban Vienna, Austria
Authors: Schreilechner Marcellus Gregor , Eichkitz Christoph Georg
Published: March 2013

To support plans to expand the current subway network in Vienna to the south, several exploratory wells were drilled along one possible corridor. In one well, gas was encountered in a 20-cm sand layer at a depth of 38 m. The gas-bearing layer is stratigraphically part of zone D of the Pannonian. Detailed information on the stratigraphy of the Pannonian of the Vienna Basin can be found in Friedl (1931) and Papp (1951, 1953). The gas-bearing horizon consists of sand and gravel layers that probably correlate to the braided stream deposits described by Bernhard (1993). In the area where this well was drilled, the subway was planned to come to the surface and continue on elevated tracks. The foundation for the elevated railway section would likely penetrate the gas-bearing horizon. Therefore, it was important to map this horizon to determine its lateral extent and uniformity.
Passive near-surface seismic data where all else fails
Authors: Sirles Phil , Sheehan Jacob , Pendrigh Nicole
Published: March 2013

Geotechnical engineers remain busy assessing and rebuilding U.S. infrastructure, as part of the American Recovery and Reinvestment Act (ARRA) of 2009. Opportunities abound in the reconstruction of bridges and interstate highways, and also in the construction of mass transit systems. Acquiring useful shallow (< 200 ft) seismic data in noisy urban conditions has always been difficult. The site conditions beneath bridges or in high-volume traffic corridors generally preclude acquisition of quality seismic data. Acquisition adjustments historically have not been practical, and the results were seldom useful to the project engineer. But just because these sites are located in difficult urban settings does not mean geophysical imaging should be overlooked as a source of valuable information for engineering design or construction. With the advent of surface wavefield methods, particularly passive surface-wave recording, urban site conditions no longer pose the same limitations to all surface-based geophysics.
SEG's digital evolution continues at the 2012 Annual Meeting
Authors: Swiney Mick
Published: March 2013

Over the course of the past two decades it has become increasingly common to see people walking around with their phones in their hands, and the most recent SEG Annual Meeting was no different … except that they were all looking at the same thing. The 2012 SEG Annual Meeting, which took place 4–7 November 2012 in Las Vegas, USA, marked the debut of the SEG 2012 Annual Meeting app, a useful tool designed to place schedules, maps, news, and information quite literally in the palm of your hand.
Student Zone
Authors: Swidinsky Andrei , Smiarowski Adam , Bongajum Emmanuel , Saleh Ramin , Mir Reza
Published: March 2013

In June 2010 and November 2010, members of SEG's University of Toronto Student Chapter organized geo-physical field trips, sponsored by the SEG Foundation, to Miller Lake on the Bruce Peninsula, 300 km north of Toronto. Figure 1 shows the location of the peninsula and Miller Lake within southern Ontario. The field trip had three main objectives: To teach students the basics of geophysical field work and familiarize them with various geophysical survey methods; to determine the depth to the water table to help the landowner decide where to drill a well for drinking water; and to detect the presence of any shale layers, some of which may be saturated with saline water and thus to be avoided (a particular problem in the area).
Nephron filtration rate and proximal tubular fluid reabsorption in the Akita mouse model of type I diabetes mellitus
Authors: Schnermann Jurgen , Oppermann Mona , Huang Yuning
Published: March 2013

An increase of glomerular filtration rate (hyperfiltration) is an early functional change associated with type I or type II diabetes mellitus in patients and animal models. The causes underlying glomerular hyperfiltration are not entirely clear. There is evidence from studies in the streptozotocin model of diabetes in rats that an increase of proximal tubular reabsorption results in the withdrawal of a vasoconstrictor input exerted by the tubuloglomerular feedback (TGF) mechanism. In the present study, we have used micropuncture to assess single nephron function in wild type (WT) mice and in two strains of type I diabetic Ins2+/- mice in either a C57Bl/6 (Akita) or an A1AR-/- background (Akita/A1AR-/-) in which TGF is non-functional. Kidney glomerular filtration rate (GFR) of anesthetized mice was increased by 25% in Akita mice and by 52% in Akita/A1AR-/-, but did not differ between genotypes when corrected for kidney weight. Single nephron GFR (SNGFR) measured by end-proximal fluid collections averaged 11.8 ± 1 nl/min (n=17), 13.05 ± 1.1 nl/min (n=23; p=0.27), and 15.4 ± 0.84 nl/min (n=26; p=0.009 compared to WT; p=0.09 compared to Akita) in WT, Akita, and Akita/A1AR-/- mice respectively. Proximal tubular fluid reabsorption was not different between WT and diabetic mice and correlated with SNGFR in all genotypes. We conclude that glomerular hyperfiltration is a primary event in the Akita model of type I diabetes, perhaps driven by an increased filtering surface area, and that it is ameliorated by TGF to the extent that this regulatory system is functional.