bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Consumer Information on the Internet to the Current Evidence Base for Minimally Invasive Parathyroidectomy
Authors: McLean Timothy , Delbridge Leigh
Published: December 2009

Background

The Internet is increasingly used as a source of health information by patients. Under these circumstances, the opportunity exists for Internet sites ostensibly providing patient information to act to promote surgical referrals based on exaggerated claims. This study aims to assess quantitatively and qualitatively the Internet‐based consumer health information for minimally invasive parathyroidectomy (MIP) techniques.

Methods

This is a prospective analysis of Internet web sites. Descriptive information about specific published claims on each of the web sites was documented and compared to the published evidence base. Web sites were then rated using a validated composite score (CS) tool and an MIP score tool developed specifically for the study.

Results

The search yielded 308 web sites, which, after assessment by the inclusion criteria left 44 unique web sites suitable for analysis. “Exaggerated,” “misleading,” or “false” claims were present in 27.3% of the web sites analyzed. The false claims category had a high negative item‐total correlation with the overall score, and accuracy was found to have a statistically significant (p < 0.05) negative correlation with quality. However, analysis performed for country of origin and the organization responsible for the web site found no significant difference.

Conclusions

Web sites offering information in relation to MIP have a surprisingly high rate of claims that are not in accord with the evidence. Such claims may be posted to attract surgical referrals. It is difficult for consumers to differentiate quality consumer health web sites from poor ones as there are no hard and fast rules to differentiate them.
Risk Factors for Malignancy in Benign Papillomas of the Breast on Core Needle Biopsy
Authors: Jung So‐Youn , Kang Han‐Sung , Kwon Youngmee , Min Sun Young , Kim Eun‐A , Ko Kyoung Lan , Lee Seeyoun , Kim Seok Won
Published: December 2009

Background

This study was designed to evaluate the clinical and pathologic parameters of benign papillomas diagnosed on core needle biopsy (CNB) and predict malignancy risk after surgical excision.

Methods

We retrospectively reviewed clinicopathologic findings for 160 CNB‐diagnosed benign papillomas followed by surgical excision from 154 patients.

Results

Ten (6.3%) of the excised lesions were diagnosed as malignant. Univariate analysis showed that those that were palpable on physical examination, detected as a mass on mammography, or >1 cm on sonography were significantly associated with malignancy. In multivariate analysis, lesions that were palpable (odds ratio (OR), 29.2; 95% confidence interval (CI), 4.06–209.58; P = 0.001) or detected as a mass (OR, 5.68; 95% CI 1.08–29.87; P = 0.04) remained significantly associated with malignancy. In a CART analysis, including all variables, lesions that were palpable and associated with a mass on mammogram were confirmed as malignant.

Conclusions

Breast lesions diagnosed as benign papillomas on CNB had a 6.3% risk of being malignant. The risk was highest for lesions that were palpable and detectable as a mass on a mammogram. In addition, the low‐risk patients avoid immediate surgical excision, although they should be followed carefully.
Laparoscopic Liver Resection for Hepatocellular Carcinoma in the Left Liver: Pringle Maneuver Versus Tourniquet Method
Authors: Zhen Zuo Jun , Lau Wan Yee , Wang Feng Jie , Lai Eric C. H.
Published: December 2009

Background

A good postoperative outcome after partial hepatectomy is highly dependent on limiting operative blood loss. This study evaluated the feasibility and efficacy of the tourniquet method compared with the Pringle maneuver in laparoscopic liver resection for hepatocellular carcinoma (HCC) in the left liver.

Methods

A retrospective, nonrandomized, comparative study for laparoscopic liver resection for HCC in the left liver using the Pringle maneuver (group A) or the tourniquet method (group B) was initiated in our center between March 2004 and October 2008.

Results

Sixteen patients (group A) underwent laparoscopic liver resection using the Pringle maneuver, and 13 patients (group B) underwent laparoscopic liver resection using the tourniquet method. No differences in operation time, operative blood loss, perioperative blood transfusion, and perioperative morbidity were found between the two groups. Both groups had no postoperative mortality. The liver enzymes were significantly elevated in group A compared with group B. Group B patients also had significantly faster recovery of liver function. The postoperative hospital stay for group B was significantly shorter than group A (mean, 5.6 days vs. 8.3 days).

Conclusions

Both techniques of vascular control were equally safe, efficacious, and feasible for patients undergoing laparoscopic left‐sided liver resection. The tourniquet method gave a wider safety margin for patients with chronic liver disease with a compromised hepatic reserve by causing less ischemia‐reperfusion injury to the remnant liver.
Composition and Antioxidant Activity of Olive Leaf Extracts from Greek Olive Cultivars
Authors: Kiritsakis Kostas , Kontominas M. G. , Kontogiorgis C. , Hadjipavlou‐Litina D. , Moustakas A. , Kiritsakis A.
Published: December 2009

The olive leaf phenolic composition of the Greek cultivars koroneiki, megaritiki and kalamon was determined using LC/MS. Furthermore, the antioxidant activity of olive leaf extracts from the above three cultivars, using solvents of increasing polarity (petroleum ether, dichloromethane, methanol and methanol/water: 60/40) was evaluated using the stable free radical diphenylpicrylhydrazyl (DPPH) test. Furthermore the oxidative stability index (OSI) was compared to that of the synthetic antioxidant TBHQ and commercial oleoresin (rosemary extract). The ability of phenolic compounds to inhibit the lipoxygenase (LOX) activity was also investigated. The ten main components determined in the olive tree leaf extracts for the cultivars koroneiki and kalamon were: secologanoside, dimethyloleuropein, oleuropein diglucoside, luteolin‐7‐O‐glucoside, rutin, oleuropein, oleuroside, quercetin, ligstroside and verbascoside. Respective compounds for the cultivar megaritiki were: secologanoside, dimethyloleuropein, oleuropein diglucoside, luteolin7‐O‐glucoside, oleuropein, oleuroside, quercetin and ligstroside. In all three cultivars, oleuropein represented the main phenolic component. The solvent polarity influenced the total amount of the phenolic compounds determined. When methanol/water (60/40) was used, as solvent, more phenolic compounds were determined. The total amounts of phenols determined in the extracts, obtained by successive extractions using the above solvents, were 6,094, 5,579 and 6,196 mg/kg (mg gallic acid/kg dried olive leaves) for the cultivars megaritiki, kalamon and koroneiki, respectively. Among all extracts, methanol/water extracts exhibited the highest antioxidant activity as shown through the application of the DPPH and OSI methods. The OSI antioxidant activity followed the sequence: synthetic antioxidant TBHQ > commercial oleoresin > olive tree leaf extracts > control. Likewise, methanol/water olive leaf extracts significantly inhibited soybean lipoxygenase, although some small differences in the activity among the olive leaf extracts of the different cultivars were observed. The solvent polarity as well as the amount of the extract influenced the inhibitory activity. A positive correlation was shown between the antioxidant activity of leaf extracts and the total phenol content.
Evaluation of the Oxidative Stability of Diacylglycerol‐Enriched Soybean Oil and Palm Olein Under Rancimat‐Accelerated Oxidation Conditions
Authors: Wang Yong , Zhao Mouming , Tang Shuze , Song Keke , Han Xue , Ou Shiyi
Published: December 2009

The oxidative stability of diacylglycerol (DAG)‐enriched soybean oil and palm olein produced by partial hydrolysis using phospholipase A1 (Lecitase Ultra) and molecular distillation was investigated at 110 °C by the Rancimat method with and without addition of synthetic antioxidants. Compared with triacylglycerol oils, the DAG‐enriched oils displayed lower oxidative stability due to a higher content of unsaturated fatty acids and a lower level of tocopherols. With the addition (50–200 mg/kg) of tert‐butylhydroquinone (TBHQ) or ascorbyl palmitate (AP), the oxidative stability indicated by induction period (IP) of these DAG‐enriched oils under the Rancimat conditions was improved. The IP of the diacylglycerol‐enriched soybean oil increased from 4.21 ± 0.09 to 12.64 ± 0.42 h when 200 mg/kg of TBHQ was added, whereas the IP of the diacylglycerol‐enriched palm olein increased from 5.35 ± 0.21 to 16.24 ± 0.55 h when the same level of AP was added. Addition of TBHQ, alone and in combination with AP resulted in a significant (p ≤ 0.05) increase in oxidative stability of diacylglycerol‐enriched soybean oil. AP had a positive synergistic effect when used with TBHQ.
Subarachnoid transplantation of immortalized galanin‐overexpressing astrocytes attenuates chronic neuropathic pain
Authors: An Ke , Xu Ying , Yang Hui , Shu Hai‐hua , Xiang Hong‐bing , Tian Yu‐ke
Published: December 2009

Treatment of chronic neuropathic pain resulted from peripheral nerve injury is one of the most difficult problems in modern clinical practice. The use of cell lines as biologic “minipumps” to chronically deliver anti‐nociceptive molecules into the pain‐processing centers of spinal cord is a newly developing technique for the treatment of pain. Moreover, spinal administration of exogenous galanin (GAL) is a useful target for the treatment of chronic pain after nerve injury. Because of better histocompatibility, lower immunogenicity and reproducibility, immortalized astrocytes (IAST) have been served as a promising cellular vehicle to deliver therapeutic molecules into CNS. In this study, the rat IAST was transfected with rat preprogalanin cDNA and the galanin‐synthesizing and secreting cell line, IAST/GAL, was isolated. After cells were transplanted into the subarachnoid space of rats with chronic neuropathic pain induced by spared nerve injury (SNI) of sciatic nerve, their analgesic potential was evaluated by behavioral tests. The results showed that IAST/GAL transfected with preprogalanin gene could express and secrete significantly higher level of GAL protein in vitro and in vivo as compared with control cells. In addition, the pain‐related behaviors, thermal hyperalgesia and mechanical allodynia were significantly alleviated during the 1–7 weeks after grafts of IAST/GAL cells, which could be reversed by galanin receptor antagonist M35 temporarily. Taken together, these data suggest that subarachnoid transplant of immortalized galanin‐overexpressing astrocytes near the pain‐processing centers was able to reverse the development of chronic neuropathic pain, which offers an adjunct approach to currently used therapies for the pain management.
Estimating Contagion on the Internet: Evidence from the Diffusion of Digital/Information Products
Authors: Chandrashekaran Murali , Grewal Rajdeep , Mehta Raj
Published: December 2009

Even as the Internet continues to grow as a global platform for communication and commerce, the success of new value offerings on the Internet hinges on acquisition of new customers and retention of existing customers. Central to the flow of customers in and out of trial and repeat behavior in this burgeoning and dynamic environment, characterized by diversity among both producers and consumers of value offerings, is the process of social contagion—active word of mouth that flows among customers or passive observation of others. To estimate contagion on the Internet, the authors develop a trial-repeat purchase diffusion model for successive innovations in value offerings on the Internet. The model extends the state-of-the-art diffusion modeling by incorporating (i) dynamic market potential, (ii) heterogeneity among first-time triers, (iii) heterogeneity in word of mouth due to repeat buyers and non-repeaters (i.e., positive and negative word of mouth), and (iv) dynamic repeat purchase rate. The model also incorporates the influence of product characteristics, specifically source of innovation (i.e., whether the innovation is driven by environmental needs or competitive pressures) and product bundling, and competition. The authors test the model with weekly adoption data for 11 computer software products available on the shareware system, involving over 100 new versions in the period 1991–1994, and in a market whose size grows by a factor of fifty from early 1991 to late 1994. The findings clarify the role of word of mouth effects, competition, and product characteristics in fostering the diffusion process for digital information goods.
Variability in fatty acids of two marine copepods upon changing food supply in the coastal upwelling zone off Chile: importance of the picoplankton and nanoplankton fractions
Authors: Escribano Ruben , Pérez Claudia S.
Published: December 2009

Fatty acids composition of two marine copepods,Acartia tonsaandCentropages brachiatus, and lipid profiles of natural food assemblages were studied during the austral summer 2006 at three upwelling sites in the coastal upwelling zone off Chile, along with oceanographic conditions. Fatty acids of food supply were assessed for the picoplankton, nanoplankton and microplankton size fractions. There were marked differences in upwelling conditions among locations, as well as in their food supply in terms of quantity and quality. Differences in fatty acid composition were also found, both among food assemblages and between copepod species. Essential polyunsaturated fatty acids (PUFA; linoleic acid) and monounsaturated fatty acids (MUFA; oleic acid) dominated the picoplankton and nanoplankton size fractions of food, and they were highly represented in both species of copepods, indicating these size fractions were the major contributors to their diet. These fatty acids can thus be considered as useful trophic markers for copepods. Variation in lipid profiles between species depended on sampling sites, whereas differences in lipid composition among sampling sites were attributed to distinct upwelling conditions, which drive the changes in food quality, such that trophic response is highly dependent on food offer. Variation in fatty acids compositions of copepods may thus act as an indicator of upwelling variability. Our findings suggest that lipid transfer from primary producers to primary consumers can have a crucial role for carbon cycling in the marine food web, and that picoplankton and nanoplankton fractions are the key items of copepod diet in this upwelling system.
Reproductive biology of a bathyal hermaphrodite fish, Bathypterois mediterraneus (Osteichthyes: Ipnopidae) from the south-eastern Sardinian Sea (central-western Mediterranean)
Authors: Porcu Cristina , Follesa Maria Cristina , Grazioli Eleonora , Deiana Anna Maria , Cau Angelo
Published: December 2009

The reproductive biology of the bathyal hermaphrodite Bathypterois mediterraneus is described based on 348 specimens caught during experimental trawl surveys carried out between 800 and 1600 m depth off the south-eastern Sardinian Sea (central-western Mediterranean). Based on macroscopic and histological gonad analysis and monthly variation of GSI, the female component of the tripodfish shows a reproductive season from March to May. The male component shows, instead, a longer spawning period probably guaranteeing continuous spermatogenesis at any time of year. The oocyte size–frequency distributions in mature component indicated that the species exhibits a synchronous-group and monocyclic ovary characterized by deposition in a single batch of eggs per year (total spawner). The species has a late size at first maturity (L50) of 119 mm standard length (SL); the smallest mature specimen was 110 mm SL.
Morphogenetic observations on the marine ciliate Euplotes vannus during cell division (Protozoa: Ciliophora)
Authors: Jiang Jiamei , Shao Chen , Xu Henglong , Al-Rasheid Khaled A.S.
Published: December 2009

Morphogenetic events during the division of the marine ciliate, Euplotes vannus (Müller, 1786) Diesing, 1850 were investigated using protargol impregnation: (1) the opisthe's oral primordium develops de novo in a subsurface pouch above the marginal cirri; (2) the cirral anlagen for the frontal, ventral and transverse cirri in both dividers develop separately on the surface epi-apokinetally, cirrus I/1 and marginal anlagen for daughter cells are formed de novo separately; (3) the dorsal kinety anlagen occur in a non-typical primary pattern within the parental structures at mid-body, of which the 3 right-most ones produce the 3 caudal cirri for the proter; and (4) the opisthe acquires 2 caudal cirri from the end of the right-most 2 kineties. Based on the data available, the reasons for the variation in the number of caudal cirri in E. vannus are discussed.
The employment transitions of mid-life women: health and care effects
Authors: AUSTEN SIOBHAN , ONG RACHEL
Published: December 2009

This article provides information on the movements into and out of paid work by mid-life women. This is a group whose representation in the paid workforce is growing as population ageing proceeds and as educational qualifications expand. It is also a group that will be critical to any labour supply response to the economic challenges posed by population ageing. However, current understandings of the needs and circumstances of mid-life women in paid work are limited. To help address this knowledge gap we use data from the first five waves of the Household, Income and Labour Dynamics in Australia survey (2001–2005) to identify the causal influences of health, care and other factors on the ability of mid-life women to remain in and re-enter paid work. The results show that poor health and/or substantial care roles have a negative impact on the employment chances of this group. However, importantly, there is asymmetry in these health and care effects, in that improvements in health and/or reductions in care roles do not increase the chances of returning to paid work. This finding indicates that many mid-life women who experience poor health and/or undertake large care roles face substantial long-term negative consequences for their employment chances and, thus, their retirement and pre-retirement incomes.
Déjà vu? A decade of research on language laboratories, television and video in language learning
Authors: Vanderplank Robert
Published: December 2009

The developments in the last ten years in the form of DVD, streaming video, video on demand, interactive television and digital language laboratories call for an assessment of the research into language teaching and learning making use of these technologies and the learning paradigms underpinning them. This paper surveys research on language teaching and learning using these and older technologies since 1999, and maps out some pointers for future research. The evidence suggests that research on video and language learning using DVD and other recent technologies is already well established, bringing out a number of issues for further study. In contrast, research-led implementation of the enhanced functionality of digital language laboratories is hardly in its infancy and much language laboratory use is marginal at best.
The Patient Self-Determination Act: Potential Ethical Quandaries and Benefits
Authors: Young Ernlé W. D. , Jex Shelli A.
Published: December 2009

As Part of the Omnibus Budget Reconciliation Act of 1990, the Patient Self Determination Act (PSDA) legislates new responsibilites for healthcare facilities. The authors served as members of the California Consortium on Patient Self-Determination, and the materials produced by this group offer healthcare facilities a valuable guide for implementing the PSDA. The ACt follows a historical trend led by doctrines of informed consent and increasing patient autonomy regarding rights to accept or refuse medical treatment and to execute advance directives. The requirements of the Act will influence healthcare facilities and how they communicate with patients about advance directives. Although the Act seeks to increase awareness of advance directices among all participants in healthcare interactions, it could pose major stumbling blocks to providing sensitive and humane care if certain concerns are nor addressed adequatley. The benefits of the Act could be far reaching and substantial for patients and healthcare facilities alike.
Intersections of Western Biomedical Ethics and World Culture: Problematic and Possibility
Authors: Pellegrino Edmund D.
Published: December 2009

Culture and ethics are inextricably bound to each other. Culture provides the moral presuppositions and ethics the formal normative framework for our moral choices. Every ethical system, therefore, is ultimately a synthesis of intuitive and rational assertions, the proportions of each varying from culture to culture. There is also in every culture an admixture of the ethnocentric and the universal that is indissolubly bound to a particular geography, history, language, and ethic strain and is common to all humans as humans.
Transplant Recipients Seletion: Peacetime vs. Wartime Triage
Authors: Rhodes Rosamond , Miller Charles , Schwartz Myron
Published: December 2009

It is a common assumption in ethics that everyone is due equal access to basic human goods. In our modern society, at least since the French Revolution, healthcare is counted along with food, shelter, and security as such a basic good. Anyone suffering from a treatable life-threatening disease can therefore, be seen as having a prima facie claim on medical treatment.
Anti-Social Powers and the Regulation of Street Sex Work
Authors: Sagar Tracey
Published: December 2009

This article focuses on the use of anti-social behavior powers in relation to a group of vulnerable women – street sex workers. It illustrates how the use of legal tools – anti-social behavior orders and public nuisance injunctions – against sex workers has been both misplaced and ineffective. The article also considers the use of anti-social powers in light of the government's leaning towards the coercive (or some might argue the compulsory) rehabilitation of sex workers. In doing so, it draws attention to the lack of research on the impact of both exclusion orders and rehabilitation orders for sex workers. Whilst it is important to fill this knowledge gap, it is argued that future investigations in this area would benefit from social network research approaches.
Seasonal and interannual variability of downwelling in the Beaufort Sea
Authors: Yang Jiayan
Published: December 2009

In this paper, we examine the seasonal and interannual to decadal variability of oceanic downwelling in the Beaufort Sea. The surface wind stress is the primary driver for variability in the upper Arctic Ocean and sea ice. The seasonal variability of the surface wind over the western Arctic is strongly influenced by a high sea level pressure center that emerges in the fall and diminishes in the summer. The wind stress and sea ice velocity are both anticyclonic from fall to spring and thus force an upwelling along the Alaskan and Canadian coast and downwelling in the interior Beaufort Sea. The upwelling and downwelling varied significantly on the interannual to decadal time scales from 1979 to 2006. There was no significant correlation between the upwelling/downwelling rate in the Beaufort Sea and the Arctic Oscillation index over this 28 year period. The coastal upwelling and interior downwelling in the Beaufort Sea had gradually intensified from 1979 to 2006. This change was almost entirely due to the increase in sea ice velocity according to three additional sensitivity calculations. The anticyclonic ice velocity over the western Arctic Ocean accelerated in the 28 year period, and the acceleration was not driven solely by the wind stress. The geostrophic wind condition was actually similar between 1979–1986 and 1997–2004. However, the ice velocity was much greater in the latter period. We hypothesize that the change in ice dynamics (thinner and less areal coverage) was responsible for the change of ice velocity.
Dual nitrate isotopes in dry deposition: Utility for partitioning NOx source contributions to landscape nitrogen deposition
Authors: Elliott E. M. , Kendall C. , Boyer E. W. , Burns D. A. , Lear G. G. , Golden H. E. , Harlin K. , Bytnerowicz A. , Butler T. J. , Glatz R.
Published: December 2009

Dry deposition is a major component of total atmospheric nitrogen deposition and thus an important source of bioavailable nitrogen to ecosystems. However, relative to wet deposition, less is known regarding the sources and spatial variability of dry deposition. This is in part due to difficulty in measuring dry deposition and associated deposition velocities. Passive sampling techniques offer potential for improving our understanding of the spatial distribution and sources of gaseous and aerosol N species, referred to here as dry deposition. We report dual nitrate isotopic composition (δ15N and δ18O) in actively collected dry and wet deposition across the high‐deposition region of Ohio, New York, and Pennsylvania. We also present results from initial tests to examine the efficacy of using passive nitric acid collectors as a collection medium for isotopic analysis at a site in New York. Isotopic values in actively collected dry deposition, including particulate nitrate and gaseous nitric acid, are compared with those in wet nitrate deposition and surrounding NOx emission sources. δ15N values in dry and wet fractions are highest at the westernmost sites and lowest at the easternmost sites, and stationary source NOx emissions (e.g., power plants and incinerators) appear to be the primary control on δ15N spatial variability. In contrast, δ18O values show a less consistent spatial pattern in dry deposition. Both δ15N and δ18O show strong seasonality, with higher values in winter than summer. Seasonal variations in stationary source NOx emissions appear to be the most likely explanation for seasonal variations in δ15N, whereas seasonal variations in air temperature and solar radiation indicate variable chemical oxidation pathways control δ18O patterns. Additionally, we demonstrate the utility of passive samplers for collecting the nitric acid (HNO3) component of dry deposition suitable for isotopic analysis. We observe slight differences in δ15N‐HNO3 values between simultaneous samples collected actively and passively (0.6‰). However, we observe a larger offset in δ18O values between actively and passively collected samples; the causes for this offset warrant further investigation. Nonetheless, passive sample collection represents a significant cost savings over active sampling techniques and could allow a more extensive understanding of patterns of dry deposition and associated insights to nitrogen sources across landscapes.
A predictive model for reach morphology classification in mountain streams using multilayer perceptron methods
Authors: Altunkaynak Abdüsselam , Strom Kyle B.
Published: December 2009

This study uses multilayer perceptron (MP) methods to develop classification models for predicting cascade, step‐pool, plane bed, and pool‐riffle type reach morphologies in mountain streams. Several models were developed with MP and classical linear regression methods on the basis of the following input variables: channel slope (S), sediment size (d84), bankfull depth (h), and bankfull width (w). Data for model calibration and testing were compiled from previous studies in mountain environments. The data were divided into separate calibration (training) and testing (prediction) sets for both the MP and classical linear regression methods; model performance was based on the percentage of accurately predicted reach morphologies using the testing portion of the data. The results indicate that (1) the MP models outperformed the linear regression models for reach morphology classification; (2) relative submergence (h/d84) was useful for classifying step‐pool and pool‐riffle reaches but performed poorly in discriminating cascade and plane bed type reaches; (3) inclusion of channel slope in models was important for classifying cascade type reaches; and (4) plane bed reaches were the most difficult to classify and delineate from pool‐riffle reaches. The two best performing MP models included the input variables (S, h/d84) and (S, h/d84, w). The overall predictive accuracy for classification of reach type for the two models was 81% and 83%, respectively, with predictive accuracies by reach type as follows: cascade, 100%; step‐pool, 81%; plane bed, 67%; pool‐riffle, 88% (first model) and cascade, 100%; step‐pool, 87%; plane bed, 70%; pool‐riffle, 90% (second model).
Oct-4 controls cell-cycle progression of embryonic stem cells
Authors: Lee Jungwoon , Go Yeorim , Kang Inyoung , Han Yong-Mahn , Kim Jungho
Published: December 2009

Mouse and human ES (embryonic stem) cells display unusual proliferative properties and can produce pluripotent stem cells indefinitely. Both processes might be important for maintaining the ‘stemness’ of ES cells; however, little is known about how the cell-cycle fate is regulated in ES cells. Oct-4, a master switch of pluripotency, plays an important role in maintaining the pluripotent state of ES cells and may prevent the expression of genes activated during differentiation. Using ZHBTc4 ES cells, we have investigated the effect of Oct-4 on ES cell-cycle control, and we found that Oct-4 down-regulation in ES cells inhibits proliferation by blocking cell-cycle progression in G0/G1. Deletion analysis of the functional domains of Oct-4 indicates that the overall integrity of the Oct-4 functional domains is important for the stimulation of S-phase entry. We also show in the present study that the p21 gene is a target for Oct-4 repression. Furthermore, p21 protein levels were repressed by Oct-4 and were induced by the down-regulation of Oct-4 in ZHBTc4 ES cells. Therefore the down-regulation of p21 by Oct-4 may contribute to the maintenance of ES cell proliferation.
Proteomic identification and characterization of secreted N‐glycosylated NPC2 following cross‐linking of the high‐affinity receptor for IgE on mast cells
Authors: Pathak Ashutosh K. , Helm Birgit A.
Published: December 2009

Allergen‐mediated cross‐linking of the high‐affinity receptor for IgE on mast cells triggers the release of diverse preformed and de novo synthesized immunoregulatory mediators that further the allergic response. A proteomic screen applied to the detection of proteins secreted by the model rat mast cell line, RBL‐2H3 (rat basophilic leukaemia, subline 2H3.1), led to the identification of the cholesterol‐binding glycoprotein, NPC2/RE1 (Niemann–Pick Type C2/epididymal secretory protein 1). Glycosylated NPC2 is secreted early in response to an IgE‐mediated stimulus and co‐localizes with the lysosomal membrane marker, CD63. NPC2 belongs to the ML (MD‐2‐related lipid‐recognition) protein family (155 members), which includes the Toll‐like receptor co‐factors, MD‐1 and MD‐2, and perhaps most interestingly, seven major house dust mite allergens of unknown function (including Der p 2 and Der f 2). Possible role(s) for the protein in the allergic response and future applications of this approach are discussed.
Ethanol-induced vasoconstriction is mediated via redox-sensitive cyclo-oxygenase-dependent mechanisms
Authors: Yogi Alvaro , Callera Glaucia E. , Hipólito Ulisses V. , Silva Catiane R. , Touyz Rhian M. , Tirapelli Carlos R.
Published: December 2009

The present study investigated the role of ROS (reactive oxygen species) and COX (cyclo-oxygenase) in ethanol-induced contraction and elevation of [Ca2+]i (intracellular [Ca2+]). Vascular reactivity experiments, using standard muscle bath procedures, showed that ethanol (1–800 mmol/l) induced contraction in endothelium-intact (EC50: 306±34 mmol/l) and endothelium -denuded (EC50: 180±40 mmol/l) rat aortic rings. Endothelial removal enhanced ethanol-induced contraction. Preincubation of intact rings with L-NAME [NG-nitro-L-arginine methyl ester; non-selective NOS (NO synthase) inhibitor, 100μmol/l], 7-nitroindazole [selective nNOS (neuronal NOS) inhibitor, 100μmol/l], oxyhaemoglobin (NO scavenger, 10μmol/l) and ODQ (selective inhibitor of guanylate cyclase enzyme, 1μmol/l) increased ethanol-induced contraction. Tiron [O2− (superoxide anion) scavenger, 1 mmol/l] and catalase (H2O2 scavenger, 300 units/ml) reduced ethanol-induced contraction to a similar extent in both endothelium-intact and denuded rings. Similarly, indomethacin (non-selective COX inhibitor, 10μmol/l), SC560 (selective COX-1 inhibitor, 1μmol/l), AH6809 [PGF2α (prostaglandin F2α)] receptor antagonist, 10μmol/l] or SQ29584 [PGH2(prostaglandin H2)/TXA2 (thromboxane A2) receptor antagonist, 3μmol/l] inhibited ethanol-induced contraction in aortic rings with and without intact endothelium. In cultured aortic VSMCs (vascular smooth muscle cells), ethanol stimulated generation of O2− and H2O2. Ethanol induced a transient increase in [Ca2+]i, which was significantly inhibited in VSMCs pre-exposed to tiron or indomethacin. Our data suggest that ethanol induces vasoconstriction via redox-sensitive and COX-dependent pathways, probably through direct effects on ROS production and Ca2+ signalling. These findings identify putative molecular mechanisms whereby ethanol, at high concentrations, influences vascular reactivity. Whether similar phenomena occur in vivo at lower concentrations of ethanol remains unclear.
Pressure-induced complexation of NH3BH3–H2
Authors: Chellappa Raja S. , Somayazulu Maddury , Struzhkin Viktor V. , Autrey Thomas , Hemley Russell J.
Published: December 2009

High pressure Raman spectroscopy of NH3BH3–H2 mixtures up to 60GPa reveals unusual pressure-induced complexation and intermolecular interactions. Stretching modes of H2 in the complex arise at 6.7 and 10GPa, increasing in frequency with pressure of up to 60GPa with different pressure coefficients, and at ∼40GPa, the lower frequency mode approaches vibron frequency of bulk H2. Pressure-induced transformations in pure NH3BH3 studied up to 60GPa reveal a disorder-order transition at 1GPa (phase II) and further transitions at 5 (phase III) and 10GPa (phase IV). The spectra of both pure NH3BH3 and the NH3BH3–H2 complex provide evidence for strengthened of the N–Hδ+⋯Hδ−–B dihydrogen bonding linkages up to 50GPa, beyond which they weaken. The dihydrogen bonding breaks down due to interactions with H2 between 15 and 20GPa in the NH3BH3–H2 complex. The behavior of the ν(NH3) modes in the NH3BH3–H2 complex indicates a dominant role of the NH3 functional group in the observed interactions.
Comment on “Anticipating synchronization of chaotic systems with time delay and parameter mismatch” [Chaos 19, 013104 (2009)]
Authors: Zhang Yinping
Published: December 2009

In the referenced paper, the proof of Theorem 1 makes use of an incorrect inequality. Hence, there are concerns with conclusions drawn when the result is used to investigate anticipating synchronization for chaotic systems with time delay and parameter mismatch in the framework of the master-slave configuration.
Polar order and diffuse scatter in Ba(Ti1−xZrx)O3 ceramics
Authors: Miao S. , Pokorny J. , Pasha U. M. , Thakur O. P. , Sinclair D. C. , Reaney I. M.
Published: December 2009

The Ba(Ti1−xZrx)O3 (BTZ) system with x≤0.35 has been studied using a combination of x-ray diffraction, dielectric measurements, Raman spectroscopy, and electron diffraction with a view to better understand the changes in structure and correlation length of polar order as a function of composition and temperature. Careful fitting of Raman spectra has confirmed stabilization of the orthorhombic phase at room temperature in x=0.05 with mixed phase (orthorhombic and rhombohedral) present at 80 K. Raman data suggest that the rhombohedral phase is most likely to be present at low temperature for x=0.15 and 0.25 and that only short range polar order evolves in x=0.35. Interpretation of the Raman spectra is in broad agreement with the dielectric data as a function of composition and temperature. Diffuse scatter at room temperature in high order zone axis electron diffraction remains essentially identical for all compositions irrespective of structure and correlation length of polar order. The diffuse maxima are therefore considered not to relate directly to the correlation length of polar order in the BTZ system and therefore do not contribute to the dielectric behavior.
Using wave-packet interferometry to monitor the external vibrational control of electronic excitation transfer
Authors: Biggs Jason D. , Cina Jeffrey A.
Published: December 2009

We investigate the control of electronic energy transfer in molecular dimers through the preparation of specific vibrational coherences prior to electronic excitation, and its observation by nonlinear wave-packet interferometry (nl-WPI). Laser-driven coherent nuclear motion can affect the instantaneous resonance between site-excited electronic states and thereby influence short-time electronic excitation transfer (EET). We first illustrate this control mechanism with calculations on a dimer whose constituent monomers undergo harmonic vibrations. We then consider the use of nl-WPI experiments to monitor the nuclear dynamics accompanying EET in general dimer complexes following impulsive vibrational excitation by a subresonant control pulse (or control pulse sequence). In measurements of this kind, two pairs of polarized phase-related femtosecond pulses following the control pulse generate superpositions of coherent nuclear wave packets in optically accessible electronic states. Interference contributions to the time- and frequency-integrated fluorescence signals due to overlaps among the superposed wave packets provide amplitude-level information on the nuclear and electronic dynamics. We derive the basic expression for a control-pulse-dependent nl-WPI signal. The electronic transition moments of the constituent monomers are assumed to have a fixed relative orientation, while the overall orientation of the complex is distributed isotropically. We include the limiting case of coincident arrival by pulses within each phase-related pair in which control-influenced nl-WPI reduces to a fluorescence-detected pump-probe difference experiment. Numerical calculations of pump-probe signals based on these theoretical expressions are presented in the following paper [J. D. Biggs and J. A. Cina, J. Chem. Phys. 131, 224302 (2009)].
Planar silicon light emitting arrays for the 3–12 μm spectral band
Authors: Malyutenko V. K. , Malyutenko O. Yu. , Bogatyrenko V. V. , Tykhonov A. M. , Piotrowski Tadeusz , Grodecki Remigiusz , Pultorak Jerzy , Wegrzecki Maciej
Published: December 2009

Silicon light emitting diode arrays made by industrial planar technology and operating at T>300 K in the double injection mode have been shown to be an efficient emitters of the infrared (IR) radiation in the 3–12 μm spectral band. We show that due to free carrier injection in an optically thin base, which makes its emissivity to increase at the wavelengths of the free carrier absorption, the devices have thermal emission output power of 2–3 mW and local power density up to 1 mW/mm2 at T=473 K. The 0.5-mm-thick 6×6 mm2 emitting pixel of an array demonstrates the power conversion efficiency of 13%, a time response of 300 μs, and an apparent temperature of the IR radiation of 400 K, which make the device practical for use in IR dynamic scene simulation techniques.
Electronic excitations in doped monolayer graphenes
Authors: Chiu C. W. , Lee S. H. , Chen S. C. , Lin M. F.
Published: December 2009

The energy dispersions and the electronic excitations of doped monolayer graphenes are, respectively, calculated from the tight-binding model and the random phase approximation. The special features of excitation spectra are dominated by the Fermi energy, the band structure, the doping type, and the transferred momentum (q). Doping would induce free carriers, which further cause the intraband single-particle and collective excitations. Due to the band asymmetry of about EF=0, the low-frequency excitation spectra exhibit a huge difference between the electron and hole doping. The hole doping causes the excitations with lower frequency, and one intraband and interband plasmon changes into one intraband plasmon and one interband plasmon at certain q. However, the high-frequency excitations are independent of the Fermi energy and the doping type. The excitation properties extremely differ from those of the band symmetry systems. The main differences, caused by the band symmetry and the Fermi energy, include the consistency of spectra among the ±EF, the plasmon peak number in the hole doping, and the q dependence of plasmon frequency.
Enhanced three-dimensional excess conductivity in Be-doped Cu0.5Tl0.5Ba2Ca3−xBex Cu4O12−δ (x=,0.5,0.75,1.0,1.25,1.5) superconductors
Authors: Irfan M. , Hassan Najmul , Manzoor Syed Asad , Shabbir Babar , Khan Nawazish Ali
Published: December 2009

We report the enhanced fluctuation-induced conductivity of Be-doped Cu0.5Tl0.5Ba2Ca3−xBex Cu4O12−δ (x=0,0.5,0.75,1.0,1.25,1.5) samples. The analysis has been done with partial substitution of Be in place of Ca. In each case excess conductivity has been analyzed and we tried to make a fit with the Aslamasov–Larkin (AL) and Lawrence–Doniach equations. It is observed that our data fit well with the three-dimensional (3D) AL equation, and a crossover from two dimensions to three dimensions has been found in our samples. We have also employed this transition to estimate the Josephson coupling strength in our samples. This interlayer coupling strength J, which controls the superconducting transition, has been found to improve with increased Be content. The Ginzburg–Landau coherence lengths ξc(0) for all cases have also been calculated. The Fourier transform infrared spectroscopy (FTIR) absorption measurements also provide a clue for the enhanced 3D fluctuations. The higher electronegativity, as well as smaller ionic size, of Be compared to Ca is suggested to be the possible source of promoting enhanced 3D character in Be-doped samples.
Neumann type integrable reduction for nonlinear evolution equations in 1+1 and 2+1 dimensions
Authors: Chen Jinbing
Published: December 2009

A family of new Neumann type systems is given in view of the nonlinearization technique, realizing the variable separation of the modified Jaulent–Miodek hierarchy and a new coupled modified Kadomtsev–Petviashvili equation on the symplectic submanifold TSN−1. By two Casimir functions and a special solution of the Lenard eigenvalue equation, we deduce the Lax–Moser matrix of the Neumann type systems that yields integrals of motion and the constrained Hamiltonians whose vector fields are tangent to TSN−1. Based on the Dirac–Poisson bracket and a Lax equation on TSN−1, a new systematic way is proposed to prove the Liouville integrability of a family of Neumann type systems synchronously. The Dirac–Poisson bracket and the generating function are used to reveal the explicit relation between infinite dimensional integrable systems and Neumann type systems, and then we point out that compatible solutions of Neumann type systems yield the finite parametric solutions of 1+1 and 2+1 dimensional integrable nonlinear evolution equations and the finite-gap solutions of the Novikov equation.
Structure and properties of the Zn+–D2 complex
Authors: Dryza V. , Bieske E. J.
Published: December 2009

The infrared spectrum of the Z66n+–D2 complex is measured in the D–D stretch region (2815–2866 cm−1) by detecting Zn+ photofragments. The spectrum is consistent with the Zn+–D2 complex consisting of a slightly distorted D2 molecule attached to a ground state Zn+ ion in a T-shaped equilibrium configuration. From the rotational constants, the vibrationally averaged intermolecular bond length is deduced to be 2.32 Å, contracting by 0.02 Å upon excitation of the D–D stretch vibrational mode. The band center of the D–D stretch transition is shifted by −154.8 cm−1 from the Q01 transition of the free D2 molecule. Density functional theory calculations are performed to elucidate the molecular bonding in the complex. The current spectroscopic and calculated data for Zn+–D2, together with the previously determined binding energy for Zn+–H2 [1310 cm−1; P. Weis, et al., J. Phys. Chem. A 101, 2809 (1997)], result in a comprehensive characterization of the Zn+–D2 and Zn+–H2 complexes.
Micromagnetic study of spin-transfer driven ferromagnetic resonance: Equivalent circuit
Authors: Carpentieri Mario , Torres Luis , Martinez Eduardo
Published: December 2009

Micromagnetic computations are used to describe spin-transfer driven ferromagnetic resonance in a nanopillar spin-valve with elliptical cross section. Nonuniform magnetization resonance is found. With the aim of describing the resonance phenomena, an equivalent electrical circuit is proposed, and its electrical parameters are deduced from micromagnetic simulations. Comparisons of spin-torque nano-oscillators with conventional voltage-controlled oscillators are also provided.
Optical amplification in Er3+-doped transparent Ba2NaNb5O15 single crystal at 850 nm
Authors: Haro-González P. , Martín I. R. , Lahoz F. , González-Pérez S. , Cavalli E. , Capuj N. E.
Published: December 2009

Positive optical gain around 5 cm−1 (∼21 dB/cm) has been observed in Er3+-doped Ba2NaNb5O15 single crystal using a pump and probe experimental setup. High power laser pulses at 532 nm have been used as the pump source in order to strongly populate the S43/2(H211/2) levels of the Er3+ ions due to ground state absorption. Low signal beam cw laser radiation at 850 nm has been used as the probe beam to stimulate the emission associated with the S43/2(H211/2)→I413/2 electronic transition of the Er3+ ions. The process has been modelized as a four level system, and its population has been analyzed and simulated in order to study the gain dynamics. Optical amplification of the probe signal has been observed during the first 60 μs, which represents a good agreement between the measured lifetime of the S43/2(H211/2) levels and the reported simulation.
Determination of the electron temperature by optical emission spectroscopy in a 13.56 MHz dusty methane plasma: Influence of the power
Authors: Massereau-Guilbaud Véronique , Géraud-Grenier Isabelle , Plain André
Published: December 2009

Optical emission spectroscopy is applied to the study of a radiofrequency (13.56 MHz) discharge in methane used to obtain hydrogenated carbon films and particles. The methane dissociation allows the creation of species in the plasma bulk as H2, H, and CH. The emission lines of these species are studied as a function of time and of incident rf power. The electron temperature is determined from the two line radiance ratio method and the corona balance model using the Balmer lines (Hα, Hβ, and Hγ). The incident rf power enhancement in the range 40–120 W leads to the increase in the emission line intensities as the electron temperature decreases. The temporal variations of CH and hydrogen emission lines, of the dc self-bias voltage, and of the electron temperature are correlated both with the particle behavior and growth in the plasma, and with the coating that grows onto the powered electrode.