bluuebunny/crossref_metadata_2025 huggingface dataset:
Autism spectrum disorders in Hispanics and non-Hispanics
Authors: Chaidez Virginia , Hansen Robin L. , Hertz-Picciotto Irva
Published: March 2012

Objectives

To compare differences in autism between Hispanic and non-Hispanics. We also examined the relationship between multiple language exposure and language function and scores of children.

Methods

The Childhood Autism Risks from Genetics and the Environment (CHARGE) study is an ongoing population-based case-control study with children sampled (n=1061) from three strata: those with autism (AU) or autism spectrum disorder (ASD); developmental delay (DD); or the general population (GP).

Results

Non-Hispanic cases demonstrated higher cognitive composite scores for the Mullen Scales of Early Learning (MSEL). There were significant associations between multiple language exposure and MSEL subscales for receptive language and expressive language, in both cases (AU/ASD) and TD controls, but not DD controls. Results of multivariate regression analyses suggest several predictors to be associated with lower Mullen expressive language scores including: diagnosis of ASD/AU, speaking to the child in a second language 25-50% of the time and Hispanic ethnicity; while maternal college education was associated with higher scores.

Conclusion

Overall, the CHARGE Hispanic group displayed more similarities than differences compared to non-Hispanics in terms of autistic phenotypes and maladaptive & adaptive scores for cases. The relationship between multiple language use and cognitive scores warrants a closer look.
Beneath the ‘Digital Native’ myth
Authors: Smith Jonathan , Skrbis Zlatko , Western Mark
Published: March 2012

As young people’s internet use shapes their experiences of education, work and personal relationships, their portrayal as ‘Digital Natives’ suggests that they are invariably better positioned than preceding generations to capitalize on such changes. Recent debates in internet use research undermine this view. While acknowledging socio-demographic differences in use, theorists disagree as to whether these reflect disparities in internet access, processes of social stratification, or users’ rational assessment of risks and opportunities. Incorporating these views, this article develops a framework for investigating differences in academic and social internet use by using data from 6444 high school students in Queensland, Australia. The results show that different factors structure students’ entry into these use pathways. Since social use depends on one’s home access context, remote students with poorer access spent less time on this activity, whereas students at independent and Catholic schools were heavier academic users, because they possessed the requisite academic orientation.
The Implications of Increasing Age on Erectile Dysfunction
Authors: Wagle Kamal C. , Carrejo Maurita H. , Tan Robert S.
Published: March 2012

Erectile dysfunction (ED) has long been correlated with psychological well-being. More recently, an understanding has developed of ED being, in some cases, a vascular condition of the penile artery. Given the narrowness of the penile artery, a small amount of atherosclerosis may result in ED before any other manifestations are evident, making ED a useful marker for other vascular conditions with potentially greater clinical implications. In light of this, possible underreporting of ED takes on added significance. A questionnaire regarding ED prevalence and management was distributed for self-administration to men in the waiting room of primary care clinics; the data were analyzed with a focus on the relationship between ED and age. The study had a remarkable response rate of >95%. The prevalence of ED in the ≥70-year age-group was 77%, compared with 61% in the 40- to 69-year age-group ( p = .0001). ED correlated linearly with age ( R2 = .80, p < .0001). Among those who had ED, more than half had not discussed it with any provider; the likelihood of discussing ED did increase with the reported severity of symptoms ( p < .0001). Older men had more severe ED than younger men ( p < .0001). Furthermore, 72% of men with a history of ED were never treated. Younger men were more likely to be treated than older men ( p = .004). Given the potential implications of underreporting ED, and the willingness of the men in this study to complete the questionnaire, further work may be merited on new models for ED assessment and follow-up.
Predictors of Serum Vitamin D Levels in African American and European American Men in Chicago
Authors: Murphy Adam B. , Kelley Brian , Nyame Yaw A. , Martin Iman K. , Smith Demetria J. , Castaneda Lauren , Zagaja Gregory J. , Hollowell Courtney M. P. , Kittles Rick A.
Published: March 2012

Vitamin D deficiency is epidemiologically linked to prostate, breast, and colon cancer. When compared with European American (EA) men, African American (AA) men have increased risk of prostate cancer, but few studies evaluate vitamin D status in AA men. The authors evaluate the biological and environmental predictors of vitamin D deficiency in AA and EA men in Chicago, Illinois, a low ultraviolet radiation environment. Blood samples were collected from 492 men, aged between 40 and 79 years, from urology clinics at three hospitals in Chicago, along with demographic and medical information, body mass index, and skin melanin content using a portable narrow-band reflectometer. Vitamin D intake and ultraviolet radiation exposure were assessed using validated questionnaires. The results demonstrated that Black race, cold season of blood draw, elevated body mass index, and lack of vitamin D supplementation increase the risk of vitamin D deficiency. Supplementation is a high-impact, modifiable risk factor. Race and sunlight exposure should be taken into account for recommended daily allowances for vitamin D intake.
Constitutional Theory and its Limits – Reflections on Comparative Political Theologies
Authors: Diamantides Marinos
Published: March 2012

This article first argues that the thinking behind different theories of collective self-constitution – normative political and reflexive – is commonly restricted by the particularly occidental metaphysics of medieval natural theology which rendered transcendence immanent and domesticated and absolutized God’s unlimited power. The article then shows how this “defective immanence” of constitutional thinking functions ideologically through retroactively colonizing other forms of “theo-politics” in non-occidental monotheistic socio-political organizations.
Characterisation and quantification of microstructural banding in dual phase steels Part 1 – General 2D study
Authors: McGarrity K S , Sietsma J , Jongbloed G
Published: March 2012

In order to quantify the degree of banding in dual phase steel, optical micrographs of various dual phased steel microstructures have been analysed. From the binary images of the micrographs, greyscale profiles are created and used to define the bands within the image. Two parameters are calculated from the defined bands: band continuity index Cb and perpendicular continuity index Cp. The first parameter quantitatively describes the continuity of each band along the direction of banding, while the second parameter quantitatively describes the continuity of the bands perpendicular to the banding direction. Both parameters are bounded on [0,1], with 0 indicating no banding and 1 indicating strong banding.
Interstitial hardening of duplex 2205 stainless steel by low temperature carburisation: enhanced mechanical and electrochemical performance
Authors: Kahn H , Heuer A H , Michal G M , Ernst F , Sharghi-Moshtaghin R , Ge Y , Natishan P M , Rayne R J , Martin F J
Published: March 2012

The mechanical properties and corrosion resistance of duplex (ferrite–austenite) grade 2205 stainless steel have been substantially improved by interstitial hardening using low temperature carburisation. The austenite phase of the duplex stainless steel responds to low temperature carburisation in a similar manner as single phase austenitic stainless steels, forming ‘expanded’ austenite (also called S phase). The surface layer that forms on the ferritic portion of 2205 steel consists of a paraequilibrium carbide, a carbide with the same metal composition as the underlying ferrite. This two-phase case has about three times the Vickers hardness of non-treated material, an improved ultimate tensile strength and increased fatigue resistance, and much improved crevice corrosion resistance.
Influence of number of coatings on properties of sol–gel spin coated CdO thin films
Authors: Rajammal R , Rajaram K , Savarimuthu E , Arumugam S
Published: March 2012

Cadmium oxide (CdO) semiconducting thin films have been obtained by sol–gel spin coating technique on glass substrates by varying the number of coatings. It has been found that the prepared thin films have exhibited very good structural, electrical, optical and surface morphological properties. The experimental results confirm that the number of coatings has a strong influence on the properties of these CdO films. The X-ray diffraction patterns of the films show well defined rock salt cubic structure. The films deposited at the optimised number of coatings exhibited a resistivity of 2·55×10−3 Ω cm, a transmittance of 80% at 600 nm and a band gap of 2·28 eV with a good uniform smooth surface.
Influence of HVOF process parameters on microstructure and bond strength of NiCrAlY coatings
Authors: Taheri M , Valefi Z , Zangeneh-Madar K
Published: March 2012

In the present study, NiCrAlY coatings were applied on steel substrate using high velocity oxygen fuel spraying process. The spray parameters were varied in order to study their influence on the coating properties. Powder and coating microstructures were investigated by a combination of X-ray diffraction, optical and scanning electron microscopy as well as energy dispersive spectroscopy analysis. Bond strength and microhardness tests were also performed on the coatings. It was found that the propane flowrate, the oxygen flowrate, the spray distance and powder feedrate have a significant effect on the coating characteristics. Finally, with the aim of minimising oxygen content and maximising bond strength, the optimum parameters were selected as the preferred spray parameters.
Phytic acid conversion coating on AZ31B magnesium alloy
Authors: Gao H F , Zhang S T , Liu C L , Xu J Q , Li J
Published: March 2012

A phytic acid conversion coating was formed on AZ31B magnesium alloy and its optimum processing parameters were also investigated by hydrogen evolution method in this work. The surface morphology, element compositions and corrosion resistance of coating were examined by atomic force microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy electrochemical measurements, and hydrogen evolution method. The results show that the optimum processing parameters of coating are pH value of 2, treating time of 40 min, treating temperature of 40°C and solution concentration of 4 g L−1. The conversion coating, composed of O, C, P, Mg, Al and Zn, consists of two layers, the compact inner layer and the outer layer with some fine cracks. The treated sample has better corrosion resistance and protection characteristic than the untreated sample.
Deposition of carbon based materials by continuous and pulsed discharges
Authors: Cicala G
Published: March 2012

This review surveys the recent developments in the plasma deposition of polycrystalline diamond (PCD) films from highly diluted (1%CH4 in H2) gas mixture and superhydrophobic fluorocarbon films from C2F4 gas. Specifically, the pulsed plasmas are also used and examined at different duty cycles and pulse periods. Emphasis is given to the role of pulsed plasmas with respect to continuous ones in controlling the gas surface interaction and the growth chemistry and in determining the material properties. The obtained materials have been characterised using a wide range of methods: scanning electron microscopy, atomic force microscopy, Raman spectroscopy, X-ray diffractometry, spectroscopic ellipsometry, water contact angle, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. Power modulation affects the PCD film morphology but deteriorates their optical and structural properties: the refractive index and the quality factor of continuous films are better than pulsed ones. As for fluorocarbon films, the control of both the plasma phase and the film deposited is improved under pulsed conditions. The pulsed plasmas, contrary to the continuous ones, allow to tune the CF2 growth precursor and correspondingly the composition, structure and morphology of the film, exhibiting a superwater repellent surface with contact angles of up to 170°.
Ultrasound enhanced plasma surface modification at atmospheric pressure
Authors: Kusano Y , Singh S V , Norrman K , Drews J , Leipold F , Rozlosnik N , Bardenshtein A , Krebs N
Published: March 2012

Efficiency of atmospheric pressure plasma treatment can be highly enhanced by simultaneous high power ultrasonic irradiation onto the treating surface. It is because ultrasonic waves with a sound pressure level (SPL) above ∼140 dB can reduce the thickness of a boundary gas layer between the plasma and the material surface, and thus, many reactive species generated in the plasma can reach the surface before they are inactivated and can be efficiently utilised for surface modification. In the present work, glass fibre reinforced polyester plates were treated using a dielectric barrier discharge and a gliding arc at atmospheric pressure to study adhesion improvement. The effect of ultrasonic irradiation with the frequency diapason between 20 and 40 kHz at the SPL of ∼150 dB was investigated. After the plasma treatment without ultrasonic irradiation, the wettability was significantly improved. The ultrasonic irradiation during the plasma treatment consistently enhanced the treatment efficiency. The principal effect of ultrasonic irradiation can be attributed to enhancing surface oxidation during plasma treatment. In addition, ultrasonic irradiation can suppress arcing, and the uniformity of the treatment can be improved.
Porosity measurement of electroless Ni–P coatings reinforced by CNT or SiC particles
Authors: Zarebidaki A , Allahkaram S-R
Published: March 2012

Ni–P composite coatings containing SiC nanoparticles or carbon nanotubes (CNTs) were deposited on steel substrates via electroless plating technique. An electrochemical polarisation technique was employed to measure the porosity of Ni–P and composite coatings in as plated condition. The technique was based on the changes observed in the corrosion potential with varying cathode and/or anode area on a bimetallic corroding system. Electrochemical impedance spectroscopy (EIS) test was used to assess the corrosion resistance of the coatings. Results showed that incorporation of nanoscaled second phases could decrease the area fraction of porosity from 2··5×10−5 for Ni–P coating to 2×10−7 for Ni–P–CNT coating. Ni–P–CNT coating exhibited the least porosity that it could be attributed to the morphology of CNTs and their ability to fill out the pores more effectively as compared to SiC nanoparticles. EIS results were in agreement with the porosity results as Ni–P–CNT coatings illustrated the highest corrosion resistance.
Influence of solvothermal time on oxidation resistance of carbon/carbon composites modified by borate sol
Authors: Huang J -F , Zhu J , Cao L -Y , Fei J , Wu J -P
Published: March 2012

Carbon/carbon (C/C) composites were modified with a borate sol–gel precursor by a novel process integrating sol–gel and solvothermal processes in order to improve the low temperature antioxidation properties of the C/C composites. Results show that the surface of the modified composites is covered by a molten B2O3 layer, and the oxidation resistance of the composites is improved with the extension of solvothermal time increasing from 12 to 48 h. After oxidation at 600°C for 6 h, the oxidation rates of the modified C/C composites are gradually decreased. The mass loss of the modified C/C composites at 600°C is due to the diffusion of oxygen along the molten B2O3 layer and the vaporisation of a small amount of B2O3.
Effect of pickling on plating porosity and related electrochemical test
Authors: Guan W , Yu H Y , Jin Y , Sun D B
Published: March 2012

In many previous studies, it was stated well that acid pickling could improve the density and adhesive strength of plating. In this work, it focused on the relationship observed between the pickling time and the porosity of plating. A group of field emission SEM, EDX and profilograph detections showed that the parent metal surface profile and chemical constituent were both changed after the pickling process. Two kinds of electrochemical tests were adopted and gave a quantitative analysis to the porosity of plating. A three-dimensional nucleation model was established to explain how the porosity of plating was influenced by overvoltage and three kinds of interfacial tension. Coupled with previous investigation, it finally revealed that the pickling time should be restricted in a proper condition or the plating porosity would be increased.
Comparative behaviour of cobalt and iron base hardfacing alloys
Authors: Liu D S , Liu R P , Wei Y H , Qiu Y , Pan P , Zhu K , Gao W L
Published: March 2012

This paper aims to compare the behaviour of cobalt and iron base hardfacing alloys on hot forging dies under temper, shock and wear. Tempering resistance, shocking behaviour and wear resistance were investigated using a tubular furnace, press and pin on disc tribometer respectively. The results showed that the thermal stability of commercial iron base hardfacing alloy (named RMD248) is good below 550°C but poor in the case of higher temperature, whereas the cobalt base hardfacing alloy presents superior tempering resistance. The cobalt base hardfacing alloy possesses excellent shock hardening properties at all the experimental temperatures, but RMD248 does not, especially at high temperature (600°C). Compared with the hardfacing layer produced by RMD248, the cobalt base hardfacing layer produces high wear resistance at 600°C and high temperature oxidation resistance at 600°C for 100 h.
Electrodeposition of copper on aligned multi-walled carbon nanotubes
Authors: Schneider M , Weiser M , Dörfler S , Althues H , Kaskel S , Michaelis A
Published: March 2012

In this work, the electrochemical deposition of copper on aligned multi-walled carbon nanotubes (MWCNTs) from an aqueous electrolyte is described. The addition of sodium dodecyl sulphate has been applied to enhance wettability of the hydrophobic MWCNT surface. The transfer of the MWCNT–copper composite film from nickel substrates, as applied for the chemical vapour deposition process for carbon nanotube synthesis, onto adhesive tapes is performed. Moreover, a sandwich layer consisting of copper top layers and copper incorporated MWCNT interlayer was produced. The structure of the resulting composite material of MWCNTs and copper was characterised by scanning electron microscopy. An electrochemical investigation of the MWCNTs on nickel foil and on conductive carbon ribbon by cyclic voltammetry is presented.
Basis of CTLA-4 function in regulatory and conventional CD4+ T cells
Authors: Tai Xuguang , Van Laethem François , Pobezinsky Leonid , Guinter Terry , Sharrow Susan O. , Adams Anthony , Granger Larry , Kruhlak Michael , Lindsten Tullia , Thompson Craig B. , Feigenbaum Lionel , Singer Alfred
Published: March 2012

CTLA-4 proteins contribute to the suppressor function of regulatory T cells (Tregs), but the mechanism by which they do so remains incompletely understood. In the present study, we assessed CTLA-4 protein function in both Tregs and conventional (Tconv) CD4+ T cells. We report that CTLA-4 proteins are responsible for all 3 characteristic Treg functions of suppression, TCR hyposignaling, and anergy. However, Treg suppression and anergy only required the external domain of CTLA-4, whereas TCR hyposignaling required its internal domain. Surprisingly, TCR hyposignaling was neither required for Treg suppression nor anergy because costimulatory blockade by the external domain of CTLA-4 was sufficient for both functions. We also report that CTLA-4 proteins were localized in Tregs in submembrane vesicles that rapidly recycled to/from the cell surface, whereas CTLA-4 proteins in naive Tconv cells were retained in Golgi vesicles away from the cell membrane and had no effect on Tconv cell function. However, TCR signaling of Tconv cells released CTLA-4 proteins from Golgi retention and caused activated Tconv cells to acquire suppressor function. Therefore, the results of this study demonstrate the importance of intracellular localization for CTLA-4 protein function and reveal that CTLA-4 protein externalization imparts suppressor function to both regulatory and conventional CD4+ T cells.
Helicobacter pylori eradication therapy is effective in the treatment of early-stage H pylori–positive gastric diffuse large B-cell lymphomas
Authors: Kuo Sung-Hsin , Yeh Kun-Huei , Wu Ming-Shiang , Lin Chung-Wu , Hsu Ping-Ning , Wang Hsiu-Po , Chen Li-Tzong , Cheng Ann-Lii
Published: March 2012

An explorative study evaluates the efficacy of Helicobacter pylori (HP) eradication (HPE) therapy on early-stage gastric diffuse large B-cell lymphomas (DLBCLs) without features of mucosa-associated lymphoid tissue (MALT), the pure (de novo) DLBCLs, in comparison with its efficacy on high-grade transformed gastric MALT lymphomas, the DLBCL(MALT). In total, 50 patients of stage IE/IIE1 HP-positive gastric DLBCLs with frontline HPE treatment were included. HP infection was successfully eradicated in 100% (16/16) of the pure (de novo) DLBCL patients and 94.1% (32/34) of the DLBCL(MALT) patients. In total, 68.8% (11/16) of pure (de novo) DLBCL patients and 56.3% (18/32) of DLBCL(MALT) patients achieved complete pathologic remission (pCR) after HPE therapy. The median time to pCR was 2.1 months (95% confidence interval, 0.6%-3.7%) for pure (de novo) DLBCLs and 5.0 months (95% confidence interval, 2.8%-7.5%; P = .024) for DLBCL(MALT). At a median follow-up of 7.7 years, all patients with pCR after HPE therapy were alive and free of lymphomas, except for one patient with pure (de novo) DLBCL who died of lung cancer. Similar to DLBCL(MALT), a substantial portion of early-stage HP-positive gastric pure (de novo) DLBCLs remains HP-dependent and responds to antibiotic treatment. Prospective studies to validate the findings are warranted.
Dome-type carcinoma of the colon; a rare variant of adenocarcinoma resembling a submucosal tumor: a case report
Authors: Yamada Masayoshi , Sekine Shigeki , Matsuda Takahisa , Yoshida Masayuki , Taniguchi Hirokazu , Kushima Ryoji , Sakamoto Taku , Nakajima Takeshi , Saito Yutaka , Akasu Takayuki
Published: March 2012

Background

Dome-type carcinoma (DC) is a distinct variant of colorectal adenocarcinoma and less than 10 cases have been described in the literature. Most of the previously reported cases were early lesions and no endoscopic observations have been described so far. We herein report a case of a DC invading the subserosal layer, including endoscopic findings.

Case presentation

A highly elevated lesion in the transverse colon was diagnosed by colonoscopy in a 77-year-old man. The tumor appeared to be similar to a submucosal tumor (SMT), however, a demarcated area of reddish and irregular mucosa was observed at the top of the tumor. There were no erosions or ulcers. Laparoscopic-assisted right hemicolectomy was performed and pathological examination revealed a well-circumscribed tumor invading the subserosal layer. The tumor was a well-differentiated adenocarcinoma associated with a dense lymphocytic infiltration and showed expansive growth. The overlying mucosal layer showed high-grade dysplasia.

Conclusion

The present lesion was diagnosed as a DC of the colon invading the subserosal layer. Because the association of mucosal dysplasia is common in DCs, the detection of dysplastic epithelium would be important to discriminate DCs from SMTs.
North Korean refugee health in South Korea (NORNS) study: study design and methods
Authors: Lee Yo Han , Lee Won Jin , Kim Yun Jeong , Cho Myong Jin , Kim Joo Hyung , Lee Yun Jeong , Kim Hee Young , Choi Dong Seop , Kim Sin Gon , Robinson Courtland
Published: March 2012

Background

Understanding the health status of North Korean refugees (NKRs), and changes in health during the resettlement process, is important from both the humanitarian standpoint and the scientific perspective. The NOrth Korean Refugee health iN South Korea (NORNS) study aims to document the health status and health determinants of North Korean refugees, to observe various health outcomes as they occur while adapting to the westernized lifestyle of South Korea, and to explain the mechanisms of how health of migrants and refugees changes in the context of new environmental risks and opportunities.

Methods

The NORNS study was composed of an initial survey and a follow-up survey 3.5 years apart. Participants were recruited voluntarily among those aged 30 or more living in Seoul. The survey consists of a health questionnaire and medical examination. The health questionnaire comprises the following six domains: 1) demographic and migration information 2) disease history, 3) mental health, 4) health-related lifestyle, 5) female reproductive health, and 6) sociocultural adaptation. The medical examination comprises anthropometric measurements, blood pressure and atherosclerosis, and various biochemical measurements. Prevalence of several diseases able to be diagnosed from the medical examination, the changes between the two surveys, and the association between the outcome and other measurements, such as length of stay and extent of adaptation in South Korea will be investigated. Furthermore, the outcome will be compared to a South Korean counterpart cohort to evaluate the relative health status of NKRs.

Discussion

The NORNS study targeting adult NKRs in South Korea is a valuable study because various scales and medical measurements are employed for the first time. The results obtained from this study are expected to be utilized for developing a health policy for NKRs and North Korean people after unification. Additionally, since NKRs are an immigrant group who are the same race and have the same genetic characteristics as South Koreans, this study has the characteristics of a unique type of migrant health study.
Assessment of providers' referral decisions in Rural Burkina Faso: a retrospective analysis of medical records
Authors: Ilboudo Tegawende Pierre , Chou Yiing-Jenq , Huang Nicole
Published: March 2012

Background

A well-functioning referral system is fundamental to primary health care delivery. Understanding the providers' referral decision-making process becomes critical. This study's aim was to assess the correctness of diagnoses and appropriateness of the providers' referral decisions from health centers (HCs) to district hospitals (DHs) among patients with severe malaria and pneumonia.

Methods

A record review of twelve months of consultations was conducted covering eight randomly selected HCs to identify severe malaria (SM) cases among children under five and pneumonia cases among adults. The correctness of the diagnosis and appropriateness of providers' referral decisions were determined using the National Clinical Guidebook as a 'gold standard'.

Results

Among the 457 SM cases affecting children under five, only 66 cases (14.4%) were correctly diagnosed and of those 66 correctly diagnosed cases, 40 cases (60.6%) received an appropriate referral decision from their providers. Within these 66 correctly diagnosed SM cases, only 60.6% were appropriately referred. Among the adult pneumonia cases, 5.9% (79/1331) of the diagnoses were correctly diagnosed; however, the appropriateness rate of the provider's referral decision was 98.7% (78/79). There was only one case that should not have been referred but was referred.

Conclusions

The adherence to the National Guidelines among the health center providers when making a diagnosis was low for both severe malaria cases and pneumonia cases. The appropriateness of the referral decisions was particularly poor for children with severe malaria. Health center providers need to be better trained in the diagnostic process and in disease management in order to improve the performance of the referral system in rural Burkina Faso.
Comparative genomics and transcriptional profiles of Saccharopolyspora erythraea NRRL 2338 and a classically improved erythromycin over-producing strain
Authors: Peano Clelia , Talà Adelfia , Corti Giorgio , Pasanisi Daniela , Durante Miriana , Mita Giovanni , Bicciato Silvio , De Bellis Gianluca , Alifano Pietro
Published: March 2012

Background

The molecular mechanisms altered by the traditional mutation and screening approach during the improvement of antibiotic-producing microorganisms are still poorly understood although this information is essential to design rational strategies for industrial strain improvement. In this study, we applied comparative genomics to identify all genetic changes occurring during the development of an erythromycin overproducer obtained using the traditional mutate-and- screen method.

Results

Compared with the parental Saccharopolyspora erythraea NRRL 2338, the genome of the overproducing strain presents 117 deletion, 78 insertion and 12 transposition sites, with 71 insertion/deletion sites mapping within coding sequences (CDSs) and generating frame-shift mutations. Single nucleotide variations are present in 144 CDSs. Overall, the genomic variations affect 227 proteins of the overproducing strain and a considerable number of mutations alter genes of key enzymes in the central carbon and nitrogen metabolism and in the biosynthesis of secondary metabolites, resulting in the redirection of common precursors toward erythromycin biosynthesis. Interestingly, several mutations inactivate genes coding for proteins that play fundamental roles in basic transcription and translation machineries including the transcription anti-termination factor NusB and the transcription elongation factor Efp. These mutations, along with those affecting genes coding for pleiotropic or pathway-specific regulators, affect global expression profile as demonstrated by a comparative analysis of the parental and overproducer expression profiles. Genomic data, finally, suggest that the mutate-and-screen process might have been accelerated by mutations in DNA repair genes.

Conclusions

This study helps to clarify the mechanisms underlying antibiotic overproduction providing valuable information about new possible molecular targets for rationale strain improvement.
Gene expression profiling of HCV genotype 3a initial liver fibrosis and cirrhosis patients using microarray
Authors: Ahmad Waqar , Ijaz Bushra , Hassan Sajida
Published: March 2012

Background

Hepatitis C virus (HCV) causes liver fibrosis that may lead to liver cirrhosis or hepatocellular carcinoma (HCC), and may partially depend on infecting viral genotype. HCV genotype 3a is being more common in Asian population, especially Pakistan; the detail mechanism of infection still needs to be explored. In this study, we investigated and compared the gene expression profile between initial fibrosis stage and cirrhotic 3a genotype patients.

Methods

Gene expression profiling of human liver tissues was performed containing more than 22000 known genes. Using Oparray protocol, preparation and hybridization of slides was carried out and followed by scanning with GeneTAC integrator 4.0 software. Normalization of the data was obtained using MIDAS software and Significant Microarray Analysis (SAM) was performed to obtain differentially expressed candidate genes.

Results

Out of 22000 genes studied, 219 differentially regulated genes found with P ≤ 0.05 between both groups; 107 among those were up-regulated and 112 were down-regulated. These genes were classified into 31 categories according to their biological functions. The main categories included: apoptosis, immune response, cell signaling, kinase activity, lipid metabolism, protein metabolism, protein modulation, metabolism, vision, cell structure, cytoskeleton, nervous system, protein metabolism, protein modulation, signal transduction, transcriptional regulation and transport activity.

Conclusion

This is the first study on gene expression profiling in patients associated with genotype 3a using microarray analysis. These findings represent a broad portrait of genomic changes in early HCV associated fibrosis and cirrhosis. We hope that identified genes in this study will help in future to act as prognostic and diagnostic markers to differentiate fibrotic patients from cirrhotic ones.
Immobilization of enzyme and antibody on ALD-HfO2-EIS structure by NH3 plasma treatment
Authors: Wang I-Shun , Lin Yi-Ting , Huang Chi-Hsien , Lu Tseng-Fu , Lue Cheng-En , Yang Polung , Pijanswska Dorota G , Yang Chia-Ming , Wang Jer-Chyi , Yu Jau-Song , Chang Yu-Sun , Chou Chien , Lai Chao-Sung
Published: March 2012

Thin hafnium oxide layers deposited by an atomic layer deposition system were investigated as the sensing membrane of the electrolyte-insulator-semiconductor structure. Moreover, a post-remote NH3 plasma treatment was proposed to replace the complicated silanization procedure for enzyme immobilization. Compared to conventional methods using chemical procedures, remote NH3 plasma treatment reduces the processing steps and time. The results exhibited that urea and antigen can be successfully detected, which indicated that the immobilization process is correct.
Rapid identification of Mycobacterium tuberculosis infection by a new array format-based surface plasmon resonance method
Authors: Hsieh Shang-Chen , Chang Chia-Chen , Lu Chia-Chen , Wei Chia-Fong , Lin Chuan-Sheng , Lai Hsin-Chih , Lin Chii-Wann
Published: March 2012

Tubercle bacillus [TB] is one of the most important chronic infectious diseases that cause millions of deaths annually. While conventional smear microscopy and culture methods are widely used for diagnosis of TB, the former is insensitive, and the latter takes up to 6 to 8 weeks to provide a result, limiting the value of these methods in aiding diagnosis and intermediate decisions on treatment. Therefore, a rapid detection method is essential for the diagnosis, prognosis assessment, and recurrence monitoring. A new surface plasmon resonance [SPR] biosensor based on an array format, which allowed immobilizing nine TB antigens onto the sensor chip, was constructed. Simultaneous determination of multiple TB antibodies in serum had been accomplished with this array-based SPR system. The results were compared with enzyme-linked immunosorbent assay, a conventional immunological method. Array-based SPR showed more advantages in providing label-free and real-time detection. Additionally, the high sensitivity and specificity for the detection of TB infection showed its potential for future development of biosensor arrays for TB diagnosis.
Nanocomposites of ZnS and poly-(dimethyl)-block-(phenyl)siloxane as a new high-refractive-index polymer media
Authors: Sergienko Natalia , Godovsky Dmitri , Zavin Boris , Lee Minjong , Ko Minjin
Published: March 2012

In the present paper, we describe a new and original method to obtain transparent, siloxane-based composites, with high refractive index (up to 1.68). The method is based on the decomposition of Zn-siloxane, mixed with a poly-(dimethyl)-block-(phenyl)siloxane matrix in different ratios. It was found that after treatment of such mixed metal-containing polymer blend with H2S, the nanoparticles of ZnS are formed, with the size in a 1- to 5-nm range, which allow effective increase of the refractive index of the nanocomposite mixture with poly-(dimethyl)-block-(phenyl)siloxane without loss of film transparency. We succeded to increase the refractive index from 1.54 (pure matrix) up to 1.68 (composite with a ZnS content of 4.6 vol.%). The siloxane-based compositions are optically transparent, which makes it possible to use them as light-emitting diodes or solar cell sealants or adhesives.
Measurement of tibial nerve excursion during ankle joint dorsiflexion in a weight‐bearing position with ultrasound imaging
Authors: Carroll Matthew , Yau Janet , Rome Keith , Hing Wayne
Published: March 2012

Background

The ability of peripheral nerves to stretch and slide is thought to be of paramount importance to maintain ideal neural function. Excursion in peripheral nerves such as the tibial can be measured by analysis of ultrasound images. The aim of this study was to assess the degree of longitudinal tibial nerve excursion as the ankle moved from plantar flexion to dorsiflexion in a standardised weight‐bearing position. The reliability of ultrasound imaging to measure tibial nerve excursion was also quantified.

Methods

The tibial nerve was imaged over two separate sessions in sixteen asymptomatic participants in a weight‐bearing position. Longitudinal nerve excursion was calculated from a three‐second video loop captured by ultrasound imaging using frame‐by‐frame cross‐correlation analysis. Intraclass correlation coefficients (ICC) with 95% confidence intervals (CI) were used to assess the intra‐rater reliability. Standard error of the measurement (SEM) and smallest real difference (SRD) were calculated to assess measurement error.

Results

Mean nerve excursion was 2.99 mm SEM ± 0.22 mm. The SRD was 0.84 mm for session 1 and 0.66 mm for session 2. Intra‐rater reliability was excellent with an ICC = 0.93.

Conclusions

Assessment of real‐time ultrasound images of the tibial nerve via frame‐by‐frame cross‐correlation analysis is a reliable non‐invasive technique to assess longitudinal nerve excursion. The relationship between foot posture and nerve excursion can be further investigated.
Gender‐sensitive reporting in medical research
Authors: Heidari Shirin , Abdool Karim Quarraisha , Auerbach Judith D , Buitendijk Simone E , Cahn Pedro , Curno Mirjam J , Hankins Catherine , Katabira Elly , Kippax Susan , Marlink Richard , Marsh Joan , Marusic Ana , Nass Heidi M , Montaner Julio , Pollitzer Elizabeth , Ruiz‐Cantero Maria Teresa , Sherr Lorraine , Sow Papa Salif , Squires Kathleen , Wainberg Mark A
Published: March 2012

Sex and gender differences influence the health and wellbeing of men and women. Although studies have drawn attention to observed differences between women and men across diseases, remarkably little research has been pursued to systematically investigate these underlying sex differences. Women continue to be underrepresented in clinical trials, and even in studies in which both men and women participate, systematic analysis of data to identify potential sex‐based differences is lacking. Standards for reporting of clinical trials have been established to ensure provision of complete, transparent and critical information. An important step in addressing the gender imbalance would be inclusion of a gender perspective in the next Consolidated Standards of Reporting Trials (CONSORT) guideline revision. Uniform Requirements for Manuscripts Submitted to Biomedical Journals, as a set of well‐recognized and widely used guidelines for authors and biomedical journals, should similarly emphasize the ethical obligation of authors to present data analyzed by gender as a matter of routine. Journal editors are also promoters of ethical research and adequate standards of reporting, and requirements for inclusion of gender analyses should be integrated into editorial policies as a matter of urgency.
Moving instead of asking? Performance-based tests and BASFI-questionnaire measure different aspects of physical function in ankylosing spondylitis
Authors: van Weely Salima FE , van Denderen J Christiaan , Steultjens Martijn PM , van der Leeden Marike , Nurmohamed Michael T , Dekker Joost , Dijkmans Ben AC , van der Horst-Bruinsma Irene E
Published: March 2012

Introduction

Ankylosing Spondylitis (AS) is characterised by limitations in physical function. The Bath Ankylosing Spondylitis Functional Index (BASFI) is considered to be the gold-standard to assess physical function in AS patients. However, the BASFI questionnaire is a self-reported outcome measure and susceptible to subjective interpretation (under- or over-estimation). More objective outcome measures, like performance-based tests, could provide an objective outcome measurement for the evaluation of limitations in physical function. Therefore, the primary aim of this study was to determine the association between performance-based measures and the BASFI questionnaire.

Methods

In this cross-sectional study 126 AS patients completed the BASFI questionnaire and eight performance-based tests based on BASFI-items. Each test received three scores: one for performance (time or points) and a score for exertion and pain experienced during performance (using modified Borg-scale and VAS 0-100 mm, respectively). Linear regression analyses were used to assess the associations between the BASFI questionnaire and performance-based tests.

Results

The univariable association between performance and BASFI-score was moderate with a R-square of 0.31 and Beta of 0.56 (p's < 0.05). In a multivariable analysis, the association between performance, exertion and pain on the one hand and BASFI-score on the other was assessed; R-square increased to 0.54: the Beta's for exertion and pain during performance were 0.38 and 0.26, respectively; the Beta for performance decreased to 0.19 (p's < 0.05).

Conclusions

This study demonstrates that alongside actual performance, patients seem to incorporate exertion and pain in their assessment of perceived physical function on the BASFI questionnaire. Performance-based tests could provide an objective outcome measurement for the evaluation of physical function and give relevant new information in addition to the BASFI questionnaire.
3D migration for rapid imaging of total-magnetic-intensity data
Authors: Zhdanov Michael S. , Liu Xiaojun , Wilson Glenn A. , Wan Le
Published: March 2012

Three-dimensional potential field migration for rapid imaging of entire total-magnetic-intensity (TMI) surveys is introduced, and real time applications are discussed. Potential field migration is based on a direct integral transformation of the measured TMI data into a 3D susceptibility model, which could be directly used for interpretation or as an a priori model for subsequent regularized inversion. The advantage of migration is that it does not require any a priori information about the type of the sources present, nor does it rely on regularization as per inversion. Migration is very stable with respect to noise in measured data because the transform is reduced to the downward continuation of a function that is analytical everywhere in the subsurface. The 3D migration of TMI data acquired over the Reid-Mahaffy test site in Ontario, Canada is used as a test study. Our results are shown to be consistent with those results obtained from 3D regularized inversion as well as the known geology of the area. Interestingly, the migration of raw TMI data produces results very similar to the inversion of diurnally corrected and microleveled TMI data, suggesting that migration could be applied directly to real-time imaging during the acquisition.
Transforming Spatial Point Processes into Poisson Processes Using Random Superposition
Authors: Møller Jesper , Berthelsen Kasper K.
Published: March 2012

Most finite spatial point process models specified by a density are locally stable, implying that the Papangelou intensity is bounded by some integrable functionβdefined on the space for the points of the process. It is possible to superpose a locally stable spatial point processXwith a complementary spatial point processYto obtain a Poisson processX⋃Ywith intensity functionβ. Underlying this is a bivariate spatial birth-death process (Xt,Yt) which converges towards the distribution of (X,Y). We study the joint distribution ofXandY, and their marginal and conditional distributions. In particular, we introduce a fast and easy simulation procedure forYconditional onX. This may be used for model checking: given a model for the Papangelou intensity of the original spatial point process, this model is used to generate the complementary process, and the resulting superposition is a Poisson process with intensity functionβif and only if the true Papangelou intensity is used. Whether the superposition is actually such a Poisson process can easily be examined using well-known results and fast simulation procedures for Poisson processes. We illustrate this approach to model checking in the case of a Strauss process.
Bounds for the Availabilities of Multistate Monotone Systems Based on Decomposition into Stochastically Independent Modules
Authors: Gåsemyr J.
Published: March 2012

Multistate monotone systems are used to describe technological or biological systems when the system itself and its components can perform at different operationally meaningful levels. This generalizes the binary monotone systems used in standard reliability theory. In this paper we consider the availabilities and unavailabilities of the system in an interval, i.e. the probabilities that the system performs above or below the different levels throughout the whole interval. In complex systems it is often impossible to calculate these availabilities and unavailabilities exactly, but it is possible to construct lower and upper bounds based on the minimal path and cut vectors to the different levels. In this paper we consider systems which allow a modular decomposition. We analyse in depth the relationship between the minimal path and cut vectors for the system, the modules, and the organizing structure. We analyse the extent to which the availability bounds are improved by taking advantage of the modular decomposition. This problem was also treated in Butler (1982) and Funnemark and Natvig (1985), but the treatment was based on an inadequate analysis of the relationship between the different minimal path and cut vectors involved, and as a result was somewhat inaccurate. We also extend to interval bounds that have previously only been given for availabilities at a fixed point of time.
Central Limit Theorems for Law-Invariant Coherent Risk Measures
Authors: Belomestny Denis , Krätschmer Volker
Published: March 2012

In this paper we study the asymptotic properties of the canonical plugin estimates for law-invariant coherent risk measures. Under rather mild conditions not relying on the explicit representation of the risk measure under consideration, we first prove a central limit theorem for independent and identically distributed data, and then extend it to the case of weakly dependent data. Finally, a number of illustrating examples is presented.
Weak Convergence Limits for Closed Cyclic Networks of Queues with Multiple Bottleneck Nodes
Authors: Stenzel Ole , Daduna Hans
Published: March 2012

We consider a sequence of cycles of exponential single-server nodes, where the number of nodes is fixed and the number of customers grows unboundedly. We prove a central limit theorem for the cycle time distribution. We investigate the idle time structure of the bottleneck nodes and the joint sojourn time distribution that a test customer observes at the nonbottleneck nodes during a cycle. Furthermore, we study the filling behaviour of the bottleneck nodes, and show that the single bottleneck and multiple bottleneck cases lead to different asymptotic behaviours.