bluuebunny/crossref_metadata_2025 huggingface dataset:
Streamlining and Core Genome Conservation among Highly Divergent Members of the SAR11 Clade
Authors: Grote Jana , Thrash J. Cameron , Huggett Megan J. , Landry Zachary C. , Carini Paul , Giovannoni Stephen J. , Rappé Michael S.
Published: September 2012

SAR11 is an ancient and diverse clade of heterotrophic bacteria that are abundant throughout the world’s oceans, where they play a major role in the ocean carbon cycle. Correlations between the phylogenetic branching order and spatiotemporal patterns in cell distributions from planktonic ocean environments indicate that SAR11 has evolved into perhaps a dozen or more specialized ecotypes that span evolutionary distances equivalent to a bacterial order. We isolated and sequenced genomes from diverse SAR11 cultures that represent three major lineages and encompass the full breadth of the clade. The new data expand observations about genome evolution and gene content that previously had been restricted to the SAR11 Ia subclade, providing a much broader perspective on the clade’s origins, evolution, and ecology. We found small genomes throughout the clade and a very high proportion of core genome genes (48 to 56%), indicating that small genome size is probably an ancestral characteristic. In their level of core genome conservation, the members of SAR11 are outliers, the most conserved free-living bacteria known. Shared features of the clade include low GC content, high gene synteny, a large hypervariable region bounded by rRNA genes, and low numbers of paralogs. Variation among the genomes included genes for phosphorus metabolism, glycolysis, and C1 metabolism, suggesting that adaptive specialization in nutrient resource utilization is important to niche partitioning and ecotype divergence within the clade. These data provide support for the conclusion that streamlining selection for efficient cell replication in the planktonic habitat has occurred throughout the evolution and diversification of this clade.

IMPORTANCE
The SAR11 clade is the most abundant group of marine microorganisms worldwide, making them key players in the global carbon cycle. Growing knowledge about their biochemistry and metabolism is leading to a more mechanistic understanding of organic carbon oxidation and sequestration in the oceans. The discovery of small genomes in SAR11 provided crucial support for the theory that streamlining selection can drive genome reduction in low-nutrient environments. Study of isolates in culture revealed atypical organic nutrient requirements that can be attributed to genome reduction, such as conditional auxotrophy for glycine and its precursors, a requirement for reduced sulfur compounds, and evidence for widespread cycling of C1 compounds in marine environments. However, understanding the genetic variation and distribution of such pathways and characteristics like streamlining throughout the group has required the isolation and genome sequencing of diverse SAR11 representatives, an analysis of which we provide here.
Transcriptome Changes Induced by Epstein-Barr Virus LMP1 and LMP2A in Transgenic Lymphocytes and Lymphoma
Authors: Shair Kathy H. Y. , Raab-Traub Nancy
Published: September 2012

Latent membrane protein 1 (LMP1) and LMP2A affect cell growth in both epithelial cells and lymphocytes. In this study, the effects on cellular gene expression were determined by microarray analysis of transgenic mice expressing LMP1, LMP2A, or both using the immunoglobulin heavy chain promoter and enhancer. Large differential changes were detected, indicating that LMP1 and LMP2A can both potently affect host gene transcription, inducing distinct transcriptional profiles. Seventy percent of the changes detected in LMP1/2A doubly transgenic lymphocytes were also modulated by LMP1 or LMP2A alone. These common and unique expression changes indicate that the combined effects of LMP1 and LMP2A may be additive, synergistic, or inhibitory. Using significant pathway analysis, the expression changes detected in LMP1, LMP2A, and LMP1/2A transgenic B lymphocytes were predicted to commonly target cancer and inflammatory pathways. Additionally, using the correlation coefficient to calculate the regulation of known c-Rel and Stat3 transcriptional targets, both were found to be enhanced in LMP1 lymphocytes and lymphomas, and a selection of Stat3 targets was further evaluated and confirmed using quantitative reverse transcription-PCR (RT-PCR). Analyses of the effects on cell growth and viability revealed that LMP2A transgenic lymphocytes had the greatest enhanced viability
in vitro
; however, doubly transgenic lymphocytes (LMP1/2A) did not have enhanced survival in culture and these mice were similar to negative littermates. These findings indicate that the combined expression of LMP1 and LMP2A has potentially different biological outcomes than when the two proteins are expressed individually.

IMPORTANCE
The Epstein-Barr virus proteins latent membrane protein 1 (LMP1) and LMP2A have potent effects on cell growth. In transgenic mice that express these proteins in B lymphocytes, the cell growth and survival properties are also affected. LMP1 transgenic mice have increased development of lymphoma, and the LMP1 lymphocytes have increased viability in culture. LMP2A transgenic lymphocytes have altered B cell development and enhanced survival. In this study, analysis of the cellular gene expression changes in transgenic LMP1 and LMP2A lymphocytes and LMP1 lymphomas revealed that both transgenes individually and in combination affected pathways important for the development of cancer and inflammation. Importantly, the combined expression of the two proteins had unique effects on cellular expression and cell viability. This is the first study to look at the combined effects of LMP1 and LMP2A on global changes in host gene expression.
Medication intensification in diabetes in rural primary care: a cluster-randomised effectiveness trial
Authors: Billue Katherine L , Safford Monika M , Salanitro Amanda H , Houston Thomas K , Curry William , Kim Yongin , Allison Jeroan J , Estrada Carlos A
Published: September 2012

Objective

To determine the effectiveness of a provider-based intervention to improve medication intensification among patients with diabetes.

Design

Effectiveness cluster-randomised trial. Baseline and follow-up cross-sections of diabetes physicians’ patients.

Setting

Eleven U.S. Southeastern states, 2006–2008.

Participants

205 Rural primary care physicians, 95 completed the study.

Intervention

Multicomponent interactive intervention including web-based continuing medical education (CME), performance feedback and quality improvement tools.

Primary outcome measures

Medication intensification, a dose increase of an existing medication or the addition of a new class of medication for glucose, blood pressure and lipids control on any of the three most recent office visits.

Results

Of 364 physicians attempting to register, 102 were randomised to the intervention and 103 to the control arms; 95 physicians (intervention, n=48; control, n=47) provided data on their 1182 of their patients at baseline (intervention, n=715; control, n=467) and 945 patients at follow-up (intervention, n=479; control, n=466). For A1c control, medication intensification increased in both groups (intervention, pre 26.4% vs post 32.6%, p=0.022; control, pre 24.8% vs post 31.1%, p=0.033) (intervention, adjusted OR (AOR) 1.37; 95% CI 1.06 to 1.76; control, AOR 1.41 (95% CI 1.06 to 1.89)); however, we observed no incremental benefit solely due to the intervention (group-by-time interaction, p=0.948). Among patients with the worst glucose control (A1c >9%), intensification increased in both groups (intervention, pre 34.8% vs post 62.5%, p=0.002; control, pre 35.7% vs post 61.4%, p=0.008).

Conclusions

A wide-reach, low-intensity, web-based interactive multicomponent intervention had no significant incremental effect on medication intensification for control of glucose, blood pressure or lipids for patients with diabetes of physicians practising in the rural Southeastern USA.

Trial registration

NCT00403091.
A NEW CLIMATE STRATEGY BEYOND 2012: LESSONS FROM MONETARY HISTORY
Authors: MCKIBBIN WARWICK J.
Published: September 2012

The Kyoto Protocol was the outcome of many years of multilateral negotiation and political compromise with the ultimate aim of reducing the risk of dangerous climate change. Unfortunately, most of the countries that ratified the Kyoto Protocol have not taken effective action to curb greenhouse gas emissions, with many Kyoto countries not looking likely to reach their targets. There is also a lack of enthusiasm from major developing countries to take on the binding targets that form the basis of the Kyoto Protocol Approach. This has raised serious doubts about the viability of the Kyoto policy of committing countries to targets and timetables especially as a model for the current negotiations. As the science becomes more compelling that action is needed to curb greenhouse gas emissions, countries are beginning to look for more sustainable alternatives for the period beyond 2012. This paper outlines the key features that are needed in a new climate change framework beyond Kyoto drawing on lessons from monetary history. Using the analogy to the way modern central banks run monetary policy, it outlines an alternative to the Kyoto Protocol, which is a system of national climate policies coordinated around a common global price for carbon.
THE CREATIVE TENSION BETWEEN STATISTICS AND ECONOMICS
Authors: HSIAO CHENG
Published: September 2012

This paper warns the risks of uncritically adopting the mind set of statisticians in empirical analysis. The examples of vector autoregressions, forecast combinations and measurement of treatment effects are used to illustrate the fragility of statistical inference when sample observations are limited.
THE EFFICIENT MARKET HYPOTHESIS REVISITED: EVIDENCE FROM THE FIVE SMALL OPEN ASEAN STOCK MARKETS
Authors: MUNIR QAISER , CHING KOK SOOK , FUROUKA FUMITAKA , MANSUR KASIM
Published: September 2012

The efficient market hypothesis (EMH), which suggests that returns of a stock market are unpredictable from historical price changes, is satisfied when stock prices are characterized by a random walk (unit root) process. A finding of unit root implies that stock returns cannot be predicted. This paper investigates the stock prices behavior of five ASEAN (Association of Southeast Asian Nations) countries i.e., Indonesia, Malaysia, Philippines, Singapore and Thailand, for the period from 1990:1 to 2009:1 using a two-regime threshold autoregressive (TAR) approach which allows testing nonlinearity and non-stationarity simultaneously. Among the main findings, our results indicate that stock prices of Malaysia and Thailand are a non-linear series and are characterized by a unit root process, consistent with the EMH. Furthermore, we find that stock prices of Indonesia, Philippines and Singapore follow a non-linear series, however, stock price indices are stationary processes that are inconsistent with the EMH.
Regulators of blood lipids and lipoproteins? PPARδ and AMPK, induced by exercise, are correlated with lipids and lipoproteins in overweight/obese men and women
Authors: Greene Nicholas P. , Fluckey James D. , Lambert Brad S. , Greene Elizabeth S. , Riechman Steven E. , Crouse Stephen F.
Published: September 2012

PPARδ is a transcription factor regulating the expression of genes involved in oxidative metabolism, which may regulate blood cholesterols through transcription of oxidative and lipoprotein metabolism genes. To determine the association of skeletal muscle PPARδ content with blood lipids and lipoproteins before and following exercise, overweight and obese men ( n = 9) and women ( n = 7) were recruited; age, BMI, body fat percentage, and V̇o2maxwere (means ± SE) 45 ± 2.5 yr, 31.9 ± 1.4 kg/m−2, 41.1 ± 1.5%, and 26.0 ± 1.3 mLO2·kg−1·min−1, respectively. Subjects performed 12 wk of endurance exercise training (3 sessions/wk, progressing to 500 kcal/session). To assess the acute exercise response, subjects performed a single exercise session on a treadmill (70% V̇o2max, 400 kcal energy expenditure) before and after training. Muscle and blood samples were obtained prior to any exercise and 24 h after each acute exercise session. Muscle was analyzed for protein content of PPARδ, PPARα, PGC-1α, AMPKα, and the oxidative and lipoprotein markers FAT/CD36, CPT I, COX-IV, LPL, F1ATPase, ABCAI, and LDL receptor. Blood was assessed for lipids and lipoproteins. Repeated-measures ANOVA revealed no influence of sex on measured outcomes. PPARδ, PGC-1α, FAT/CD36, and LPL content were enhanced following acute exercise, whereas PPARα, AMPKα, CPT I, and COX-IV content were enhanced only after exercise training. PPARδ content negatively correlated with total and LDL cholesterol concentrations primarily in the untrained condition ( r ≤ −0.4946, P < 0.05), whereas AMPKα was positively correlated with HDL cholesterol concentrations regardless of exercise ( r ≥ 0.5543, P < 0.05). Our findings demonstrate exercise-induced expression of skeletal muscle PPARs and their target proteins, and this expression is associated with improved blood lipids and lipoproteins in obese adults.
Dopamine exerts activation-dependent modulation of spinal locomotor circuits in the neonatal mouse
Authors: Humphreys Jennifer M. , Whelan Patrick J.
Published: September 2012

Monoamines can modulate the output of a variety of invertebrate and vertebrate networks, including the spinal cord networks that control walking. Here we examined the multiple changes in the output of locomotor networks induced by dopamine (DA). We found that DA can depress the activation of locomotor networks in the neonatal mouse spinal cord following ventral root stimulation. By examining disinhibited rhythms, where the Renshaw cell pathway was blocked, we found that DA depresses a putative recurrent excitatory pathway that projects onto rhythm-generating circuitry of the spinal cord. This depression was D2 but not D1 receptor dependent and was not due exclusively to depression of excitatory drive to motoneurons. Furthermore, the depression in excitation was not dependent on network activity. We next compared the modulatory effects of DA on network function by focusing on a serotonin and a N-methyl-dl-aspartate-evoked rhythm. In contrast to the depressive effects on a ventral root-evoked rhythm, we found that DA stabilized a drug-evoked rhythm, reduced the frequency of bursting, and increased amplitude. Overall, these data demonstrate that DA can potentiate network activity while at the same time reducing the gain of recurrent excitatory feedback loops from motoneurons onto the network.
Gating reaction mechanism of neuronal NMDA receptors
Authors: Borschel William F. , Myers Jason M. , Kasperek Eileen M. , Smith Thomas P. , Graziane Nicholas M. , Nowak Linda M. , Popescu Gabriela K.
Published: September 2012

The activation mechanisms of recombinant N-methyl-d-aspartate receptors (NRs) have been established in sufficient detail to account for their single channel and macroscopic responses; however, the reaction mechanism of native NRs remains uncertain due to indetermination of the isoforms expressed and possible neuron-specific factors. To delineate the activation mechanism of native NRs, we examined the kinetic properties of currents generated by individual channels located at the soma of cultured rat neurons. Cells were dissociated from the embryonic cerebral cortex or hippocampus, and on-cell single channel recordings were done between 4 and 50 days in vitro (DIV). We observed two types of kinetics that correlated with the age of the culture. When we segregated recordings by culture age, we found that receptors recorded from early (4–33 DIV) and late (25–50 DIV) cultures had smaller unitary conductances but had kinetic profiles that matched closely those of recombinant 2B- or 2A-containing receptors, respectively. In addition, we examined the effects of cotransfection with postsynaptic density protein 95 or neuropilin tolloid-like protein 1 on recombinant receptors expressed in human embryonic kidney-293 cells. Our results add support to the view that neuronal cultures recapitulate the developmental patterns of receptor expression observed in the intact animal and demonstrate that the activation mechanism of somatic neuronal NRs is similar to that described for recombinant receptors of defined subunit composition.
Carrier-Based Common Mode Voltage Control Techniques in Three-Level Diode-Clamped Inverter
Authors: Chaturvedi Pradyumn , Jain Shailendra , Agarwal Pramod
Published: September 2012

Switching converters are used in electric drive applications to produce variable voltage, variable frequency supply which generates harmful large dv/dt and high-frequency common mode voltages (CMV). Multilevel inverters generate lower CMV as compared to conventional two-level inverters. This paper presents simple carrier-based technique to control the common mode voltages in multilevel inverters using different structures of sine-triangle comparison method such as phase disposition (PD), phase opposition disposition (POD) by adding common mode voltage offset signal to actual reference voltage signal. This paper also presented the method to optimize the magnitude of this offset signal to reduce CMV and total harmonic distortion in inverter output voltage. The presented techniques give comparable performance as obtained in complex space vector-based control strategy, in terms of number of commutations, magnitude, and rate of change of CMV and harmonic profile of inverter output voltage. Simulation and experimental results presented confirm the effectiveness of the proposed techniques to control the common mode voltages.
MCP-1-Induced Histamine Release from Mast Cells Is Associated with Development of Interstitial Cystitis/Bladder Pain Syndrome in Rat Models
Authors: Lv Jianwei , Huang Yiran , Zhu Shiguo , Yang Ganggang , Zhang Yujian , Leng Jing , Bo Juanjie , Liu Dongming
Published: September 2012

Objective. Interstitial cystitis/bladder pain syndrome (IC/BPS) is characterized by overexpression of monocyte chemoattractant protein-1 (MCP-1) in bladder tissues and induction of mast cell (MC) degranulation. This study was undertaken to explore the mechanism of action of MCP-1 in the development of IC/BPS.Methods. A rat model of IC/BPS was developed by perfusing bladders of nine SPF- grade female Sprague-Dawley rats with protamine sulfate and lipopolysaccharide (PS+LPS). MCP-1 and histamine levels in bladder tissue and urine were detected by immunohistochemistry and ELISA. MC degranulation was measured by immunofluorescence techniques and chemokine (C-C motif) receptor 2 (CCR2) was assayed by flow cytometry.Results. Increased MCP-1 expression in bladder tissue and elevated MCP-1 and histamine levels were observed in the urine of LS+LPS-treated rats. This was accompanied by the expression of CCR2 on MC surfaces, suggesting MCP-1 may induce MC degranulation through CCR2. Exposure to LPS stimulated MCP-1 expression in bladder epithelial cells, and exposure to MCP-1 induced histamine release from MCs.Conclusions. MCP-1 upregulation in IC/BPS is one of possible contributing factors inducing histamine release from MCs. CCR2 is involved in the process of mast cell degranulation in bladder tissues. These changes may contribute to the development of symptoms of IC/BPS.
Association ofXmnI Polymorphism and Hemoglobin E Haplotypes on Postnatal Gamma Globin Gene Expression in Homozygous Hemoglobin E
Authors: Ekwattanakit Supachai , Monteerarat Yuwarat , Riolueang Suchada , Tachavanich Kalaya , Viprakasit Vip
Published: September 2012

Background and Objectives. To explore the role ofcis-regulatory sequences within theβglobin gene cluster at chromosome 11 on humanγglobin gene expression related to Hb E allele, we analyze baseline hematological data and Hb F values together withβglobin haplotypes in homozygous Hb E.Patients and Methods. 80 individuals with molecularly confirmed homozygous Hb E were analyzed for theβglobin haplotypes andXmnI polymorphism using PCR-RFLPs. 74 individuals with complete laboratory data were further studied for association analyses.Results. Eight differentβglobin haplotypes were found linked to Hb E alleles; three major haplotypes were (a) (III), (b) (V), and (c) (IV) accounting for 94% of Hb E chromosomes. A new haplotype (Th-1) was identified and most likely converted from the major ones. The majority of individuals had Hb F < 5%; only 10.8% of homozygous Hb E had high Hb F (average 10.5%, range 5.8–14.3%). No association was found on a specific haplotype orXmnI in these individuals with high Hb F, measured by alkaline denaturation. Conclusion. The cis-regulation ofγglobin gene expression might not be apparent under a milder condition with lesser globin imbalance such as homozygous Hb E.
Medical Image Compression Based on Vector Quantization with Variable Block Sizes in Wavelet Domain
Authors: Jiang Huiyan , Ma Zhiyuan , Hu Yang , Yang Benqiang , Zhang Libo
Published: September 2012

An optimized medical image compression algorithm based on wavelet transform and improved vector quantization is introduced. The goal of the proposed method is to maintain the diagnostic-related information of the medical image at a high compression ratio. Wavelet transformation was first applied to the image. For the lowest-frequency subband of wavelet coefficients, a lossless compression method was exploited; for each of the high-frequency subbands, an optimized vector quantization with variable block size was implemented. In the novel vector quantization method, local fractal dimension (LFD) was used to analyze the local complexity of each wavelet coefficients, subband. Then an optimal quadtree method was employed to partition each wavelet coefficients, subband into several sizes of subblocks. After that, a modifiedK-means approach which is based on energy function was used in the codebook training phase. At last, vector quantization coding was implemented in different types of sub-blocks. In order to verify the effectiveness of the proposed algorithm, JPEG, JPEG2000, and fractal coding approach were chosen as contrast algorithms. Experimental results show that the proposed method can improve the compression performance and can achieve a balance between the compression ratio and the image visual quality.
The Pain Crisis: What It Is and What Can Be Done
Authors: Sessle Barry J.
Published: September 2012

Chronic pain is present in epidemic proportions in most countries, is often unrelieved, and has a huge socioeconomic impact. It is not just a “medical” illness but indeed is a problem that faces all healthcare professional fields. Several steps are identified to address this crisis. These include approaches to enhance pain awareness and access to timely and effective care for pain, and educational and research approaches to improve the knowledge base of healthcare professionals and students and diagnostic and management procedures for pain. Several opportunities to enhance pain understanding, access, and management are also identified.
Molecular Markers with Predictive and Prognostic Relevance in Lung Cancer
Authors: Rose-James Alphy , TT Sreelekha
Published: September 2012

Lung cancer accounts for the majority of cancer-related deaths worldwide of which non-small-cell lung carcinoma alone takes a toll of around 85%. Platinum-based therapy is the stronghold for lung cancer at present. The discovery of various molecular alterations that underlie lung cancer has contributed to the development of specifically targeted therapies employing specific mutation inhibitors. Targeted chemotherapy based on molecular profiling has shown great promise in lung cancer treatment. Various molecular markers with predictive and prognostic significance in lung cancer have evolved as a result of advanced research. Testing of EGFR and Kras mutations is now a common practice among community oncologists, and more recently, ALK rearrangements have been added to this group. This paper discusses various predictive and prognostic markers that are being investigated and have shown significant relevance which can be exploited for targeted treatment in lung cancer.
Mechanisms and Mediators of Inflammation: Potential Models for Skin Rejection and Targeted Therapy in Vascularized Composite Allotransplantation
Authors: Hautz Theresa , Wolfram Dolores , Grahammer Johanna , Starzl Ravi , Krapf Christoph , Pratschke Johann , Lee W. P. Andrew , Brandacher Gerald , Schneeberger Stefan
Published: September 2012

Vascularized composite allotransplantation (VCA) is an effective treatment option for patients suffering from limb loss or severe disfigurement. However, postoperative courses of VCA recipients have been complicated by skin rejection, and long-term immunosuppression remains a necessity for allograft survival. To widen the scope of this quality-of-life improving procedure minimization of immunosuppression in order to limit risks and side effects is needed. In some aspects, the molecular mechanisms and dynamics of skin allograft rejection seem similar to inflammatory skin conditions. T cells are key players in skin rejection and are recruited to the skin via activation of adhesion molecules, cytokines, and chemokines. Blocking these molecules has not only shown success in the treatment of inflammatory dermatoses, but also prolonged graft survival in various models of solid organ transplantation. In addition to T cell recruitment, ectopic lymphoid structures within the allograft associated with chronic rejection in solid organ transplantation might contribute to the strong alloimmune response towards the skin. Selectively targeting the molecules involved offers exciting novel therapeutic options in the prevention and treatment of skin rejection after VCA.
Analysis of Edge Detection in Bar Code Symbols: An Overview and Open Problems
Authors: Krešić-Jurić Saša
Published: September 2012

Accurate edge localization is essential in bar code decoding. Since speckle noise is the most dominant form of noise in laser bar code scanners, it is important to fully understand its effects on edge detection. Starting with the basic statistical properties of speckle patterns, we present stochastic analysis of speckle noise. We derive the autocorrelation function and power spectral density (PSD) of the noise in terms of intensity distribution of the scanning beam. We then study the signal‐to‐noise ratio for signals that result from scanning different configurations of edges. Next, we consider statistical properties of edge localization error caused by speckle noise. We show that the standard deviation of the error is determined by the PSD of the noise and relative positions of edges in a bar code symbol. Based on the analysis presented here, we propose new criteria for system design.
Transitional Failure of Carbon Nanotube Systems under a Combination of Tension and Torsion
Authors: Jeong Byeong-Woo
Published: September 2012

Transitional failure envelopes of single‐ and double‐walled carbon nanotubes under combined tension‐torsion are predicted using classical molecular dynamics simulations. The observations reveal that while the tensile failure load decreases with combined torsion, the torsional buckling moment increases with combined tension. As a result, the failure envelopes under combined tension‐torsion are definitely different from those under pure tension or torsion. In such combined loading, there is a multitude of failure modes (tensile failure and torsional buckling), and the failure consequently exhibits the feature of transitional failure envelopes. In addition, the safe region of double‐walled carbon nanotubes is significantly larger than that of single‐walled carbon nanotubes due to the differences in the onset of torsional buckling.
An Optimization of Tree Topology Based Parallel Cryptography
Authors: Damrudi Masumeh , Ithnin Norafida
Published: September 2012

Public key cryptography has become of vital importance regarding the rapid development of wireless technologies. The RSA is one of the most important algorithms for secure communications in public‐key cryptosystems. Since the RSA is expensive in terms of computational task which is modular exponentiation, parallel processing and architecture is a reasonable solution to speedup RSA operations. In this paper, taking into account pipelining and optimization, we improve throughput and efficiency of the TRSA method, a parallel architecture solution for RSA security based on tree topology. The optimization and pipelining of the tree based architecture increases its efficiency and throughput. The experimental results demonstrate that these pipelined and optimized approaches outperform the main TRSA.
Pure Nano-Rotation Scanner
Authors: Lee Moo-Yeon , Park Eun-Joo , Yeom Jeong-Kuk , Hong Dong-Pyo , Lee Dong-Yeon
Published: September 2012

We developed and tested a novel rotation scanner for nano resolution and accurate rotary motion about the rotation center. The scanner consists of circular hinges and leaf springs so that the parasitic error at the center of the scanner in the X and Y directions is minimized, and rotation performance is optimized. Each sector of the scanner's system was devised to have nano resolution by minimizing the parasitic errors of the rotation center that arise due to displacements other than rotation. The analytic optimal design results of the proposed scanner were verified using finite element analyses. The piezoelectric actuators were used to attain nano-resolution performances, and a capacitive sensor was used to measure displacement. A feedback controller was used to minimize the rotation errors in the rotation scanner system under practical conditions. Finally, the performance evaluation test results showed that the resonance frequency was 542 Hz, the resolution was 0.09 μrad, and the rotation displacement was 497.2 μrad. Our test results revealed that the rotation scanner exhibited accurate rotation about the center of the scanner and had good nano precision.
Adsorption Kinetics for the Removal of Hazardous Dye Congo Red by Biowaste Materials as Adsorbents
Authors: Kaur Sumanjit , Rani Seema , Mahajan Rakesh Kumar
Published: September 2012

The present work aims to investigate the removal of dye congo red from aqueous solutions by two low‐cost biowaste adsorbents such as ground nut shells charcoal (GNC) and eichhornia charcoal (EC) under various experimental conditions. The effect of contact time, ionic strength, temperature, pH, dye concentration, and adsorbent dose on the removal of dye was studied. The kinetic experimental data were fitted to pseudo‐first order, pseudo‐second order, intraparticle diffusion, Elovich model, and Bangham’s model. Results imply that adsorption of congo red on these adsorbents nicely followed the second order kinetic model and maximum adsorption capacity was found to be 117.6 and 56.8 mg g−1 for GNC and EC at 318 K, however it increases with increase in temperature for both adsorbents. Equilibrium isotherms were analyzed by Langmuir, Freundlich, Temkin, Dubinin and Radushkevich, and Generalized Isotherms. Freundlich isotherm described the isotherm data with high‐correlation coefficients. The results of the present study substantiate that biowaste material GNC and EC are promising adsorbents for the removal of the dye congo red.
Biomarkers of HPV in Head and Neck Squamous Cell Carcinoma
Authors: Liang Caihua , Marsit Carmen J. , McClean Michael D. , Nelson Heather H. , Christensen Brock C. , Haddad Robert I. , Clark John R. , Wein Richard O. , Grillone Gregory A. , Houseman E. Andres , Halec Gordana , Waterboer Tim , Pawlita Michael , Krane Jeffrey F. , Kelsey Karl T.
Published: September 2012

Human papillomavirus (HPV) is an accepted cause of head and neck squamous cell carcinoma (HNSCC), and patients with HPV-associated HNSCC have a favorable prognosis. Currently, there is no general guidance on the most appropriate biomarkers for clinical assessment of HPV in these malignancies. We compared PCR-based and serologic HPV assays, as well as p16 immunohistochemistry, individually and in combination in a single population-based study to assess their associations with overall survival among patients with HNSCC, and thus their potential value as biomarkers. HPV16 serology was determined for 488 patients; immunohistochemical detection of p16 expression in tumors was conducted in a subset of 233 cases, and PCR-based methods to assess the presence of HPV16 DNA in a subset of 179 cases of tumors. Considering each biomarker individually in the subset of patients studied for all endpoints, seropositivity for the E6 and E7 proteins was significantly associated with enhanced all-cause survival in oropharyngeal disease [HRE6/E7+ = 0.1, 95% confidence interval (CI) = 0.02–0.3]. Neither the presence of HPV16 DNA nor p16 immunostaining was associated with significant enhanced overall survival in oropharyngeal disease (HRDNA = 0.9, 95% CI = 0.3–2.9; HRp16 = 0.3, 95% CI = 0.1–1.1). However, the combination of HPV-positive DNA and E6 or E7 serology was associated with enhanced overall survival in oropharyngeal disease (HRDNA+/E6/E7+ = 0.1, 95% CI = 0.02–1.0), whereas E6/E7 seronegative patients with evidence of HPV in tumor DNA did not show any evidence of favorable survival (HRDNA+/E6-/E7- = 3.4, 95% CI = 0.6–18.1). Furthermore, patients with p16 staining and E6 or E7 seropositivity had favorable survival from oropharyngeal disease (HRp16+/E6/E7+ = 0.1, 95% CI = 0.02–0.4), whereas patients who were p16 positive and E6/E7 seronegative had significantly increased hazard of all causes of death (HRp16+/E6-/E7- = 3.1, 95% CI = 1.2–7.7). A stronger association of HPV presence with prognosis (assessed by all-cause survival) is observed when “HPV-associated” HNSCC is defined using tumor status (HPV DNA status or P16) and HPV E6/E7 serology in combination rather using tumor HPV status alone. Cancer Res; 72(19); 5004–13. ©2012 AACR.
Arterial Spin Labeling Imaging Findings in Transient Ischemic Attack Patients: Comparison with Diffusion- and Bolus Perfusion-Weighted Imaging
Authors: Zaharchuk Greg , Olivot Jean-Marc , Fischbein Nancy J. , Bammer Roland , Straka Matus , Kleinman Jonathan T. , Albers Gregory W.
Published: September 2012

Background: Since transient ischemic attacks (TIAs) can predict future stroke, it is important to distinguish true vascular events from non-vascular etiologies. Arterial spin labeling (ASL) is a non-contrast magnetic resonance (MR) method that is sensitive to cerebral perfusion and arterial arrival delays. Due to its high sensitivity to minor perfusion alterations, we hypothesized that ASL abnormalities would be identified frequently in TIA patients, and could therefore help increase clinicians’ confidence in the diagnosis. Methods: We acquired diffusion-weighted imaging (DWI), intracranial MR angiography (MRA), and ASL in a prospective cohort of TIA patients. A subset of these patients also received bolus contrast perfusion-weighted imaging (PWI). Two neuroradiologists evaluated the images in a blinded fashion to determine the frequency of abnormalities on each imaging sequence. Kappa (ĸ) statistics were used to assess agreement, and the χ2 test was used to detect differences in the proportions of abnormal studies. Results: 76 patients met the inclusion criteria, 48 (63%) of whom received PWI. ASL was abnormal in 62%, a much higher frequency compared with DWI (24%) and intracranial MRA (13%). ASL significantly increased the MR imaging yield above the combined DWI and MRA yield (62 vs. 32%, p < 0.05). Arterial transit artifact in vascular borderzones was the most common ASL abnormality (present in 51%); other abnormalities included focal high or low ASL signal (11%). PWI was abnormal in 31% of patients, and in these, ASL was abnormal in 14 out of 15 cases (93%). In hemispheric TIA patients, both PWI and ASL findings were more common in the symptomatic hemisphere. Agreement between neuroradiologists regarding abnormal studies was good for ASL and PWI [ĸ = 0.69 (95% CI 0.53–0.86) and ĸ = 0.66 (95% CI 0.43–0.89), respectively]. Conclusion: In TIA patients, perfusion-related alterations on ASL were more frequently detected compared with PWI or intracranial MRA and were most frequently associated with the symptomatic hemisphere. Almost all cases with a PWI lesion also had an ASL lesion. These results suggest that ASL may aid in the workup and triage of TIA patients, particularly those who cannot undergo a contrast study.
Hepatitis C Virus Infection and Related Risk Factors among Injection Drug Users in Montenegro
Authors: Baćak Valerio , Laušević Dragan , Mugoša Boban , Vratnica Zoran , Terzić Nataša
Published: September 2012

Background: In Southeastern Europe, similar to other postsocialist regions on the continent, injection drug users (IDU) are exposed to a high risk of blood-borne infections. In this paper, we report the prevalence of HIV, hepatitis C (HCV) and hepatitis B (HBV) among IDUs in Montenegro. We also examine the risk factors associated with HCV diagnosis. Methods: In 2008, 322 IDUs in Montenegro participated in a respondent-driven sampling survey. Blood specimens were collected and tested for HIV, HCV and HBV. Behavioral data were collected with self-administered questionnaires. Results: In comparison to 2005, HCV prevalence had increased from an estimated 22 to 53.7%. Only one HIV and no HBV cases were detected. Anti-HCV positivity was associated with the region of origin, income, sharing injection equipment and frequency of injecting drugs. Conclusion: The increasing HCV prevalence among IDUs in Montenegro calls for increased and better designed programs to prevent its further spread and a potential HIV outbreak.
Hyperreflective Dots: A New Spectral-Domain Optical Coherence Tomography Entity for Follow-Up and Prognosis in Exudative Age-Related Macular Degeneration
Authors: Coscas Gabriel , De Benedetto Umberto , Coscas Florence , Li Calzi Concetta I. , Vismara Sabrina , Roudot-Thoraval Françoise , Bandello Francesco , Souied Eric
Published: September 2012

Purpose: Spectral-domain optical coherence tomography (SD-OCT) enables high-resolution analysis of retinal layers and previously unseen hyperreflective dots (HRD). HRD morphological characteristics, evolution, possible origin and prognostic value are discussed. Methods: We conducted a prospective study of 100 patients with exudative age-related macular degeneration (AMD), who were treated and followed up with monthly imaging examinations. Statistical correlations between visual acuity (VA) and pre-/post- treatment HRD characteristics were evaluated. Results: HRD were present in all cases, mainly in the outer retinal layers but also elsewhere. After treatment, HRD regressed in a few days, 1 month (p < 0.04) and 3 months (p < 0.01). Regression was evident in all VA and morphological subsets. Resolution was associated with better final VA (p < 0.001). Conclusions: Presence of initial/recurrent HRD, rapid treatment response and the growing role that early biological inflammatory reaction plays in AMD suggests HRD are activated microglia cells. The correlation between VA and HRD could make HRD a clinical marker for early decisions about treatment and retreatment.
Paneth Cells and Necrotizing Enterocolitis: A Novel Hypothesis for Disease Pathogenesis
Authors: McElroy Steven J. , Underwood Mark A. , Sherman Michael P.
Published: September 2012

Current models of necrotizing enterocolitis (NEC) propose that intraluminal microbes destroy intestinal mucosa and activate an inflammatory cascade that ends in necrosis. We suggest an alternate hypothesis wherein NEC is caused by injury to Paneth cells (PCs) in the intestinal crypts. PCs are specialized epithelia that protect intestinal stem cells from pathogens, stimulate stem cell differentiation, shape the intestinal microbiota, and assist in repairing the gut. Our novel model of NEC uses neonatal mice and ablates PCs followed by enteral infection. We contrast this model with other animal examples of NEC and the clinical disease. Selective destruction of PCs using dithizone likely releases tumor necrosis factor-α and other inflammatory mediators. We propose that this event produces inflammation in the submucosa, generates platelet-activating factor, and induces a coagulopathy. The role of PCs in NEC is consistent with the onset of disease in preterm infants after a period of PC-related maturation, the central role of PCs in crypt-related homeostasis, the anatomic location of pneumatosis intestinalis close to the crypts, and the proximity of PCs to occluded blood vessels that cause coagulation necrosis of the intestinal villi. We offer this hypothesis to promote new thoughts about how NEC occurs and its potential prevention.
Time is Brain(stem) in Basilar Artery Occlusion
Authors: Vergouwen Mervyn D. I. , Algra Ale , Pfefferkorn Thomas , Weimar Christian , Rueckert Christina M. , Thijs Vincent , Kappelle L. Jaap , Schonewille Wouter J. ,   on behalf of the Basilar Artery International Cooperation Study (BASICS) Study Group
Published: September 2012

Background and Purpose—

The frequent use of a longer time window for recanalization therapy in patients with basilar artery occlusion (BAO) in daily practice is not supported by any scientific evidence. We investigated the relationship between time to recanalization therapy and functional outcome in BAO with data from the Basilar Artery International Cooperation Study (BASICS).

Methods—

BASICS is a prospective multicenter registry of patients (n=619) with radiologically confirmed BAO. We analyzed patients receiving intravenous thrombolysis or intra-arterial treatment. Patients were divided into 4 groups based on the interval between estimated time of BAO and start of recanalization therapy: ≤3 hours (n=134), >3 to ≤6 hours (n=151), >6 to ≤9 hours (n=56), and >9 hours (n=68). Primary outcome measure was poor functional outcome (modified Rankin scale score 4–6) after 1 month. We calculated adjusted risk ratios with 95% CIs using Poisson regression analyses with the ≤3 hours group as the reference group.

Results—

Patients had an increased risk of poor functional outcome as time to recanalization therapy became longer (≤3 hours: 62%; >3 to ≤6 hours: 67% [adjusted risk ratio, 1.06; 0.91–1.25]; >6 to ≤9 hours: 77% [adjusted risk ratio, 1.26; 1.06–1.51]; >9 hours: 85% [adjusted risk ratio, 1.47; 1.26–1.72]).

Conclusions—

Early recanalization therapy in patients with BAO is associated with a more favorable outcome with a significant increased chance of a poor outcome when recanalization therapy is started >6 hours after estimated time of BAO.
Minimally Invasive Surgery for Spontaneous Supratentorial Intracerebral Hemorrhage
Authors: Zhou Xinyu , Chen Jianjun , Li Qi , Ren Gaoping , Yao Guoen , Liu Ming , Dong Qiang , Guo Jìng , Li Leilei , Guo Jing , Xie Peng
Published: September 2012

Background and Purpose—

There has been a nonstandard surgical procedure and extensive international controversy in minimally invasive surgery (MIS) for the management of spontaneous supratentorial intracerebral hemorrhage. This meta-analysis assessed the effectiveness of MIS as compared with other treatment options, including conservative medical treatment and conventional craniotomy, in patients with supratentorial intracerebral hemorrhage.

Methods—

PubMed, Embase, Cochrane Controlled Trials Register (CCTR), Web of Science, European Association for Grey Literature Exploitation (EAGLE), National Technical Information Service (NTIS), Current Controlled Trials, Clinical Trials, International Clinical Trials Registry, Internet Stroke Center, Chinese Biomedical Literature Database (CBM), Chinese National Knowledge Infrastructure (CNKI) (last searched December 2011) were searched. Randomized controlled trials on MIS in patients with computed tomography-confirmed supratentorial intracerebral hemorrhage were included. We excluded low-quality randomized controlled trials. The death or dependence at the end of follow-up was defined as the primary outcome, and the death at the end of follow-up was defined as the secondary outcome.

Results—

The 313 randomized controlled trials met the included criteria. We only analyzed 12 high-quality randomized controlled trials involving 1955 patients. The quality of the included trials was consistently high. OR of the primary outcome and secondary outcome of MIS both showed significant reductions (OR, 0.54,
P
<0.00001; OR, 0.53,
P
<0.00001).

Conclusions—

Patients with supratentorial intracerebral hemorrhage may benefit more from MIS than other treatment options. The most likely candidates to benefit from MIS are both sexes, age of 30 to 80 years with superficial hematoma, Glasgow Coma Scale score of ≥9, hematoma volume between 25 and 40mL, and within 72 hours after onset of symptoms. Our study could help select appropriate patients for MIS and guide clinicians to optimize treatment strategies in supratentorial intracerebral hemorrhage.
IMILAST: A Community Effort to Intercompare Extratropical Cyclone Detection and Tracking Algorithms
Authors: Neu Urs , Akperov Mirseid G. , Bellenbaum Nina , Benestad Rasmus , Blender Richard , Caballero Rodrigo , Cocozza Angela , Dacre Helen F. , Feng Yang , Fraedrich Klaus , Grieger Jens , Gulev Sergey , Hanley John , Hewson Tim , Inatsu Masaru , Keay Kevin , Kew Sarah F. , Kindem Ina , Leckebusch Gregor C. , Liberato Margarida L. R. , Lionello Piero , Mokhov Igor I. , Pinto Joaquim G. , Raible Christoph C. , Reale Marco , Rudeva Irina , Schuster Mareike , Simmonds Ian , Sinclair Mark , Sprenger Michael , Tilinina Natalia D. , Trigo Isabel F. , Ulbrich Sven , Ulbrich Uwe , Wang Xiaolan L. , Wernli Heini
Published: September 2012

The variability of results from different automated methods of detection and tracking of extratropical cyclones is assessed in order to identify uncertainties related to the choice of method. Fifteen international teams applied their own algorithms to the same dataset—the period 1989–2009 of interim European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERAInterim) data. This experiment is part of the community project Intercomparison of Mid Latitude Storm Diagnostics (IMILAST; see www.proclim.ch/imilast/index.html). The spread of results for cyclone frequency, intensity, life cycle, and track location is presented to illustrate the impact of using different methods. Globally, methods agree well for geographical distribution in large oceanic regions, interannual variability of cyclone numbers, geographical patterns of strong trends, and distribution shape for many life cycle characteristics. In contrast, the largest disparities exist for the total numbers of cyclones, the detection of weak cyclones, and distribution in some densely populated regions. Consistency between methods is better for strong cyclones than for shallow ones. Two case studies of relatively large, intense cyclones reveal that the identification of the most intense part of the life cycle of these events is robust between methods, but considerable differences exist during the development and the dissolution phases.