bluuebunny/crossref_metadata_2025 huggingface dataset:
Alu expression in human cell lines and their retrotranspositional potential
Authors: Oler Andrew J , Traina-Dorge Stephen , Derbes Rebecca S , Canella Donatella , Cairns Brad R , Roy-Engel Astrid M
Published: June 2012

Background

The vast majority of the 1.1 million Alu elements are retrotranspositionally inactive, where only a few loci referred to as ‘source elements’ can generate new Alu insertions. The first step in identifying the active Alu sources is to determine the loci transcribed by RNA polymerase III (pol III). Previous genome-wide analyses from normal and transformed cell lines identified multiple Alu loci occupied by pol III factors, making them candidate source elements.

Findings

Analysis of the data from these genome-wide studies determined that the majority of pol III-bound Alus belonged to the older subfamilies Alu S and Alu J, which varied between cell lines from 62.5% to 98.7% of the identified loci. The pol III-bound Alus were further scored for estimated retrotransposition potential (ERP) based on the absence or presence of selected sequence features associated with Alu retrotransposition capability. Our analyses indicate that most of the pol III-bound Alu loci candidates identified lack the sequence characteristics important for retrotransposition.

Conclusions

These data suggest that Alu expression likely varies by cell type, growth conditions and transformation state. This variation could extend to where the same cell lines in different laboratories present different Alu expression patterns. The vast majority of Alu loci potentially transcribed by RNA pol III lack important sequence features for retrotransposition and the majority of potentially active Alu loci in the genome (scored high ERP) belong to young Alu subfamilies. Our observations suggest that in an in vivo scenario, the contribution of Alu activity on somatic genetic damage may significantly vary between individuals and tissues.
Variability of insulin sensitivity during the first 4 days of critical illness: implications for tight glycemic control
Authors: Pretty Christopher G , Le Compte Aaron J , Chase J Geoffrey , Shaw Geoffrey M , Preiser Jean-Charles , Penning Sophie , Desaive Thomas
Published: June 2012

Background

Effective tight glycemic control (TGC) can improve outcomes in critical care patients, but it is difficult to achieve consistently. Insulin sensitivity defines the metabolic balance between insulin concentration and insulin-mediated glucose disposal. Hence, variability of insulin sensitivity can cause variable glycemia. This study quantifies and compares the daily evolution of insulin sensitivity level and variability for critical care patients receiving TGC.

Methods

This is a retrospective analysis of data from the SPRINT TGC study involving patients admitted to a mixed medical-surgical ICU between August 2005 and May 2007. Only patients who commenced TGC within 12 hours of ICU admission and spent at least 24 hours on the SPRINT protocol were included (N = 164). Model-based insulin sensitivity (SI) was identified each hour. Absolute level and hour-to-hour percent changes in SI were assessed on cohort and per-patient bases. Levels and variability of SI were compared over time on 24-hour and 6-hour timescales for the first 4 days of ICU stay.

Results

Cohort and per-patient median SI levels increased by 34% and 33% (p < 0.001) between days 1 and 2 of ICU stay. Concomitantly, cohort and per-patient SI variability decreased by 32% and 36% (p < 0.001). For 72% of the cohort, median SI on day 2 was higher than on day 1. The day 1–2 results are the only clear, statistically significant trends across both analyses. Analysis of the first 24 hours using 6-hour blocks of SI data showed that most of the improvement in insulin sensitivity level and variability seen between days 1 and 2 occurred during the first 12–18 hours of day 1.

Conclusions

Critically ill patients have significantly lower and more variable insulin sensitivity on day 1 than later in their ICU stay and particularly during the first 12 hours. This rapid improvement is likely due to the decline of counter-regulatory hormones as the acute phase of critical illness progresses. Clinically, these results suggest that while using TGC protocols with patients during their first few days of ICU stay, extra care should be afforded. Increased measurement frequency, higher target glycemic bands, conservative insulin dosing, and modulation of carbohydrate nutrition should be considered to minimize safely the outcome glycemic variability and reduce the risk of hypoglycemia.
Exercise training in pulmonary arterial hypertension associated with connective tissue diseases
Authors: Grünig Ekkehard , Maier Felicitas , Ehlken Nicola , Fischer Christine , Lichtblau Mona , Blank Norbert , Fiehn Christoph , Stöckl Frank , Prange Felix , Staehler Gerd , Reichenberger Frank , Tiede Henning , Halank Michael , Seyfarth Hans-Jürgen , Wagner Simone , Nagel Christian
Published: June 2012

Introduction

The objective of this prospective study was to assess short- and long-term efficacy of exercise training (ET) as add-on to medical therapy in patients with connective tissue disease-associated pulmonary arterial hypertension (CTD-APAH).

Methods

Patients with invasively confirmed CTD-APAH received ET in-hospital for 3 weeks and continued at home for 12 weeks. Efficacy parameters have been evaluated at baseline and after 15 weeks by blinded-observers. Survival rate has been evaluated in a follow-up period of 2.9 ± 1.9 years.

Results

Twenty-one consecutive patients were included and assessed at baseline, and after 3 weeks, 14 after 15 weeks. Patients significantly improved the mean distance walked in 6 minutes compared to baseline by 67 ± 52 meters after 3 weeks (p < 0.001) and by 71 ± 35 meters after 15 weeks (p = 0.003), scores of quality of life (p < 0.05), heart rate at rest, peak oxygen consumption, oxygen saturation and maximal workload. Systolic pulmonary artery pressure and diastolic systemic blood pressure improved significantly after 3 weeks of ET. The 1- and 2-year overall-survival rates were 100%, the 3-year survival 73%. In one patient lung transplantation was performed 6 months after ET.

Conclusion

ET as add-on to medical therapy is highly effective in patients with CTD-APAH to improve work capacity, quality of life and further prognostic relevant parameters and possibly improves the 1-, 2- and 3-year survival rate. Further randomized controlled studies are needed to confirm these results.

Trial registration

ClinicalTrials.gov: NCT00491309.
Hydroxychloroquine is associated with impaired interferon-alpha and tumor necrosis factor-alpha production by plasmacytoid dendritic cells in systemic lupus erythematosus
Authors: Sacre Karim , Criswell Lindsey A , McCune Joseph M
Published: June 2012

Introduction

Plasmacytoid dendritic cells (pDCs) constitutively express two members of the Toll-like receptor (TLR) family, TLR-9 and TLR-7, through which they can be stimulated to produce high levels of interferon (IFN)-α, a key mediator of the pathogenesis of systemic lupus erythematosus (SLE). Given the known efficacy of hydroxychloroquine (HCQ) in the treatment of SLE, we examined its ability to inhibit such pDC function in vivo.

Methods

Peripheral blood mononuclear cells (PBMCs) from SLE subjects treated or not with HCQ and from healthy controls were stimulated with the TLR-9 agonist, CpG oligodeoxynucleotides (CpG-A ODN)-2216, and the TLR-7 agonist, imiquimod. The proportion of monocytes, B cells, myeloid dendritic cells, pDCs, and natural killer (NK) cells producing IFN-α and tumor necrosis factor alpha (TNF-α) was then analyzed by multiparameter flow cytometry.

Results

After TLR-9/7 stimulation in both SLE and healthy subjects, significant production of IFN-α and TNF-α was only observed in pDCs. TLR-7 and TLR-9 induced IFN-α and TNF-α production by pDCs from subjects with SLE was decreased relative to that found in controls (TLR-9/IFN-α, P < 0.0001; TLR-9/TNF-α P < 0.0001; TLR-7/TNF-α P = 0.01). TLR-9 and TLR-7 induced IFN-α and TNF-α production by pDCs was severely impaired in 36% (TLR-9) and 33% (TLR-7) of SLE subjects. In almost all cases, these subjects were being treated with HCQ (HCQ vs. no HCQ: impaired TLR-9/IFN-α, P = 0.0003; impaired TLR-7/IFN-α, P = 0.07; impaired TLR-9/TNF-α, P < 0.009; impaired TLR-7/TNF-α, P < 0.01).

Conclusions

Treatment with HCQ is associated with impaired ability of pDCs from subjects with SLE to produce IFN-α and TNF-α upon stimulation with TLR-9 and TLR-7 agonists.
Centromere protein-A, an essential centromere protein, is a prognostic marker for relapse in estrogen receptor-positive breast cancer
Authors: McGovern Susan L , Qi Yuan , Pusztai Lajos , Symmans William F , Buchholz Thomas A
Published: June 2012

Introduction

Centromere protein A (CENP-A), an essential centromere protein, has been associated with high grade cancers. This study was undertaken to determine if CENP-A is a prognostic factor for breast cancer patients not receiving systemic therapy or predictive of response to tamoxifen or neoadjuvant chemotherapy.

Methods

mRNA levels of CENP-A and CENP-B, a centromere protein that binds independently of CENP-A, were measured in breast cancer specimens from 484 patients receiving no systemic therapy, 276 patients receiving tamoxifen, and 233 patients treated with neoadjuvant chemotherapy. Associations between CENP-A, CENP-B, Ki-67, relapse, and chemotherapy response were determined.

Results

CENP-A but not CENP-B was higher in estrogen receptor (ER)-negative tumors than ER-positive tumors and positively correlated with Ki-67 expression. Among patients with ER-positive disease who received no systemic therapy or tamoxifen, higher levels of CENP-A were associated with lower rates of 5-year distant relapse free survival (DRFS). On multivariate analyses including Ki-67, high CENP-A expression had a hazard ratio of 10.9 for relapse in patients with ER-positive disease not receiving systemic therapy (95% CI, 2.86 to 41.78; P = 0.00047) and 1.64 for patients with ER-positive disease receiving tamoxifen (95% CI, 0.99 to 2.71; P = 0.054). CENP-A was not an independent prognostic marker in ER-negative tumors. For both ER-positive and ER-negative tumors, CENP-A was not a significant independent predictor of chemotherapy response.

Conclusions

CENP-A was a significant independent prognostic marker for patients with ER-positive breast cancer not treated with systemic therapy but had limited predictive value in tamoxifen treated patients and was not predictive of response to neoadjuvant chemotherapy.
Four hour creatinine clearance is better than plasma creatinine for monitoring renal function in critically ill patients
Authors: Pickering John W , Frampton Christopher M , Walker Robert J , Shaw Geoffrey M , Endre Zoltán H
Published: June 2012

Introduction

Acute kidney injury (AKI) diagnosis is based on an increase in plasma creatinine, which is a slowly changing surrogate of decreased glomerular filtration rate. We investigated whether serial creatinine clearance, a direct measure of the glomerular filtration rate, provided more timely and accurate information on renal function than serial plasma creatinine in critically ill patients.

Methods

Serial plasma creatinine and 4-hour creatinine clearance were measured 12-hourly for 24 hours and then daily in 484 patients. AKI was defined either as > 50% increase in plasma creatinine from baseline, or > 33.3% decrease in creatinine clearance. The diagnostic and predictive performance of the two AKI definitions were compared.

Results

Creatinine clearance decrease diagnosed AKI in 24% of those not diagnosed by plasma creatinine increase on entry. These patients entered the ICU sooner after insult than those diagnosed with AKI by plasma creatinine elevation (P = 0.0041). Mortality and dialysis requirement increased with the change in creatinine clearance-acute kidney injury severity class (P = 0.0021). Amongst patients with plasma creatinine < 1.24 mg/dl on entry, creatinine clearance improved the prediction of AKI considerably (Net Reclassification Improvement 83%, Integrated Discrimination Improvement 0.29). On-entry, creatinine clearance associated with AKI severity and duration (P < 0.0001) predicted dialysis need (area under the curve: 0.75) and death (0.61). A > 33.3% decrease in creatinine clearance over the first 12 hours was associated with a 2.0-fold increased relative risk of dialysis or death.

Conclusions

Repeated 4-hour creatinine clearance measurements in critically ill patients allow earlier detection of AKI, as well as progression and recovery compared to plasma creatinine.

Trial Registration

Australian New Zealand Clinical Trials Registry ACTRN012606000032550.
Marine CSEM of the Scarborough gas field, Part 1: Experimental design and data uncertainty
Authors: Myer David , Constable Steven , Key Kerry , Glinsky Michael E. , Liu Guimin
Published: June 2012

We describe the planning, processing, and uncertainty analysis for a marine CSEM survey of the Scarborough gas field off the northwest coast of Australia, consisting of 20 transmitter tow lines and 144 deployments positioned along a dense 2D profile and a complex 3D grid. The purpose of this survey was to collect a high-quality data set over a known hydrocarbon prospect and use it to further the development of CSEM as a hydrocarbon mapping tool. Recent improvements in navigation and processing techniques yielded high-quality frequency domain data. Data pseudosections exhibit a significant anomaly that is laterally confined within the known reservoir location. Perturbation analysis of the uncertainties in the transmitter parameters yielded predicted uncertainties in amplitude and phase of just a few percent at close ranges. These uncertainties may, however, be underestimated. We introduce a method for more accurately deriving uncertainties using a line of receivers towed twice in opposite directions. Comparing the residuals for each line yields a Gaussian distribution directly related to the aggregate uncertainty of the transmitter parameters. Constraints on systematic error in the transmitter antenna dip and inline range can be calculated by perturbation analysis. Uncertainties are not equal in amplitude and phase, suggesting that inversion of these data would be better suited in these components rather than in real and imaginary components. One-dimensional inversion showed that the reservoir and a confounding resistive layer above it cannot be separately resolved even when the roughness constraint is modified to allow for jumps in resistivity and prejudices are provided, indicating that this level of detail is beyond the single-site CSEM data. Further, when range-dependent error bars are used, the resolution decreases at a shallower depth than when a fixed-error level is used.
Stochastic inversion of magnetotelluric data using a sharp boundary parameterization and application to a geothermal site
Authors: Chen Jinsong , Hoversten G. Michael , Key Kerry , Nordquist Gregg , Cumming William
Published: June 2012

We developed a Bayesian model to invert magnetotelluric (MT) data using a 2D sharp boundary parameterization. We divided the 2D cross section into layers and considered the locations of interfaces and resistivity of the regions formed by the interfaces as random variables. We assumed that those variables are independent in the vertical direction and dependent along the lateral direction, whose spatial dependence is described by either pairwise difference or multivariate Gaussian priors. We used a parallel, adaptive finite-element algorithm to rapidly forward simulate frequency-domain MT responses of the 2D resistivity structure and used Markov chain Monte Carlo methods to draw many samples from the joint posterior probability distribution. We applied the Bayesian model to a synthetic case that mimics a geothermal exploration scenario. Our results demonstrated that the developed method is effective in estimating the resistivity and depths to interfaces and in quantifying uncertainty on the estimates. We also applied the developed method to the field MT data collected from the Darajat geothermal site in Indonesia. We compared our inversion results with those obtained from a deterministic inversion of 3D MT data; they are consistent even if the two inversion methods are very different and the amount of information used for inversion is different.
Endocrine-Disrupting Chemicals and Public Health Protection: A Statement of Principles from The Endocrine Society
Authors: Zoeller R. Thomas , Brown T. R. , Doan L. L. , Gore A. C. , Skakkebaek N. E. , Soto A. M. , Woodruff T. J. , Vom Saal F. S.
Published: June 2012

An endocrine-disrupting chemical (EDC) is an exogenous chemical, or mixture of chemicals, that can interfere with any aspect of hormone action. The potential for deleterious effects of EDC must be considered relative to the regulation of hormone synthesis, secretion, and actions and the variability in regulation of these events across the life cycle. The developmental age at which EDC exposures occur is a critical consideration in understanding their effects. Because endocrine systems exhibit tissue-, cell-, and receptor-specific actions during the life cycle, EDC can produce complex, mosaic effects. This complexity causes difficulty when a static approach to toxicity through endocrine mechanisms driven by rigid guidelines is used to identify EDC and manage risk to human and wildlife populations. We propose that principles taken from fundamental endocrinology be employed to identify EDC and manage their risk to exposed populations. We emphasize the importance of developmental stage and, in particular, the realization that exposure to a presumptive “safe” dose of chemical may impact a life stage when there is normally no endogenous hormone exposure, thereby underscoring the potential for very low-dose EDC exposures to have potent and irreversible effects. Finally, with regard to the current program designed to detect putative EDC, namely, the Endocrine Disruptor Screening Program, we offer recommendations for strengthening this program through the incorporation of basic endocrine principles to promote further understanding of complex EDC effects, especially due to developmental exposures.
Estrogen Promotes Prostate Cancer Cell Migration via Paracrine Release of ENO1 from Stromal Cells
Authors: Yu Lin , Shi Jiandang , Cheng Sa , Zhu Yan , Zhao Xiulan , Yang Kuo , Du Xiaoling , Klocker Helmut , Yang Xiaoli , Zhang Ju
Published: June 2012

As a key glycolytic enzyme, enolase 1 (ENO1) is critical for cellular energy metabolism. Recent studies have revealed its important role in growth and metastasis of lung, head and neck, and breast cancer. However, the regulatory mechanisms of ENO1 expression and secretion remain unclear. We observed that conditioned medium from estradiol-stimulated prostate stromal cells significantly promoted the migration of prostate cancer (PCa) cells. Two-dimensional protein electrophoresis, mass spectrometry, and immunodepletion assays identified one of the major active factors in the conditioned medium as α-type enolase (α-enolase, or ENO1). Moreover, in prostate stromal cells, estradiol not only enhanced the stability of ENO1 at the protein level in an estrogen receptor-α-dependent manner but also promoted its secretion to the extracellular matrix. Furthermore, recombinant ENO1 bound to the surface of PCa cells and promoted cell migration via their plasminogen receptor activity in a paracrine manner. Immunohistochemistry suggested that stromal ENO1 levels increased in PCa compared with those in normal tissue.
Microtubule assembly during mitosis – from distinct origins to distinct functions?
Authors: Meunier Sylvain , Vernos Isabelle
Published: June 2012

The mitotic spindle is structurally and functionally defined by its main component, the microtubules (MTs). The MTs making up the spindle have various functions, organization and dynamics: astral MTs emanate from the centrosome and reach the cell cortex, and thus have a major role in spindle positioning; interpolar MTs are the main constituent of the spindle and are key for the establishment of spindle bipolarity, chromosome congression and central spindle assembly; and kinetochore-fibers are MT bundles that connect the kinetochores with the spindle poles and segregate the sister chromatids during anaphase. The duplicated centrosomes were long thought to be the origin of all of these MTs. However, in the last decade, a number of studies have contributed to the identification of non-centrosomal pathways that drive MT assembly in dividing cells. These pathways are now known to be essential for successful spindle assembly and to participate in various processes such as K-fiber formation and central spindle assembly. In this Commentary, we review the recent advances in the field and discuss how different MT assembly pathways might cooperate to successfully form the mitotic spindle.
The mechanical properties of the non-sticky spiral inNephilaorb webs (Araneae, Nephilidae)
Authors: Hesselberg Thomas , Vollrath Fritz
Published: June 2012

Detailed information on web geometry and the material properties of the various silks used elucidates the function of the web's different structures. In this study we investigated the non-sticky spiral in Nephila edulis webs, which in this species is not removed during web-building. This permanent non-sticky spiral shows several modifications compared to other, i.e. temporary non-sticky spirals; it is zigzag shaped and wrapped around the radial thread at the elongated junctions. Material properties of silk in the non-sticky spiral and other scaffolding structures (i.e. radii, frame and anchor threads) were comparable. However, the fibre diameters differed with the non-sticky spiral threads being significantly smaller. We used the measured data in a finite element (FE) model of the non-sticky spiral in a segment of the web. The FE analysis suggested that the observed Zigzag index resulted from the application of very high pre-stresses to the outer turns of the non-sticky spiral. However, final pre-stresses in the non-sticky spiral after reorganisation were down to 300 MPa or 1.5-2 times the stress in the radii, which is probably closer to the stress applied by the spider during web-building.
The proximal costs of case construction in caddisflies: antioxidant and life history responses
Authors: Mondy Nathalie , Rey Benjamin , Voituron Yann
Published: June 2012

Animal construction allows organisms to cope with environmental variations but the physiological costs of such behaviour are still poorly understood. The aim of the present study was to measure the physiological cost of construction behaviour through the oxidative balance that is known to affect the ability of organs to function, stimulate senescence processes and ultimately impact the fitness of the organism. We used larvae of caddisfly, Limnephilus rhombicus, by experimentally modifying the effort associated with case-building. Larvae that were forced to build a new case showed a significant increase in both total antioxidant capacity and the specific activity of superoxide dismutase 48 hours and 72 hours, respectively, after the initiation of the reconstruction. These results strongly suggest that the larval construction behaviour triggered the production of reactive oxygen species but their effects were reversed 7 days after the reconstruction. In the animals that were forced to build a new case, oxidative stress appeared to be mitigated by a network of antioxidant defences because no oxidative damage was observed in proteins compared to the control larvae. At the adult stage, while the longevity was not sex-dependant and not affected by the treatment, the body weight and the body size of adult males from the reconstruction treatment were significantly lower than the control ones. Such unexpected sex effect together with data on oxidative stress highlight the difficulty to determine the physiological cost associated with energy demanding behaviours implying a consideration of both their energetic and non-energetic components.
The Cyclicality of Skill Acquisition: Evidence from Panel Data
Authors: Méndez Fabio , Sepúlveda Facundo
Published: June 2012

This paper presents new empirical evidence regarding the cyclicality of skill acquisition activities. The paper studies both training and schooling episodes at the individual level using quarterly data from the NLSY79 for a period of 19 years. We find that aggregate schooling is strongly countercyclical, while aggregate training is acyclical. Several training categories, however, behave procyclically. The results also indicate that firm-financed training is procyclical, while training financed through other means is countercyclical; and that the cyclicality of skill acquisition investments depends significantly on the educational level and the employment status of the individual. (JEL E24, E32, I20, J24)
64 multidetector CT findings of influenza A (H1N1) virus in patients with hematologic malignancies
Authors: El-Badrawy Adel , Zeidan Amany , Ebrahim Mohamed A
Published: June 2012

Background

The pandemic of swine-origin H1N1 influenza that began in early 2009 has provided evidence that radiology can assist in the early diagnosis of severe cases. Immunocompromised patients are at increased risk for morbidity and mortality. MDCT is superior to radiography in showing the distribution of the disease.

Purpose

To review the 64 multidetector CT thoracic findings of novel swine-origin influenza A (H1N1) virus in patients with hematologic malignancies.

Material and Methods

This study included 12 patients (3 women, 9 men; mean age, 32.2 years). All patients proved to be infected with influenza A (H1N1) virus. The hematologic malignancies were acute myeloid leukemia ( n = 8), chronic lymphocytic leukemia ( n = 2), multiple myeloma ( n = 1), and myelodysplastic syndrome ( n = 1). All the patients underwent CT scanning using a 64 multidetector CT scanner. Chest CT scans were reviewed for ground-glass opacities (GGOs), consolidation, airway thickening/dilatation, nodules, mediastinal lymphadenopathy, and pleural effusion.

Results

More than one CT finding was detected in every patient. Pulmonary affection was bilateral, more on the left side. The affections were mainly peribronchial. Airway wall thickening and dilatation were detected in all 12 patients, GGO in 9/12 patients, nodules in 6/12 patients, consolidation in 6/12 patients, hilar lymphadenopathy in 3/12 patients, and pleural effusion in 2/12 patients.

Conclusion

Acute myeloid leukemia is the most common hematologic malignancy affected by influenza A (H1N1) virus. The left lung is affected more than the right one. The most common multidetector CT findings are unilateral or bilateral airway thickening and dilatation. Multidetector CT can be used for early and accurate assessment of pulmonary affection with influenza A H1N1 virus infection.
Putting Money Where the Mouths Are: The Relation Between Venture Financing and Electronic Word-of-Mouth
Authors: Aggarwal Rohit , Gopal Ram , Gupta Alok , Singh Harpreet
Published: June 2012

External financing is critical to ventures that do not have a revenue source but need to recruit employees, develop products, pay suppliers, and market their products/services. There is an increasing belief among entrepreneurs that electronic word-of-mouth (eWOM), specifically blog coverage, can aid in achieving venture capital financing. Conflicting findings reported by past studies examining eWOM make it unclear what to make of such beliefs of entrepreneurs. Even if there were generally agreed-upon results, a stream of literature indicates that because of the differences in traits between the prior investigated contexts and venture capital financing, the findings from the prior studies cannot be generalized to venture capital financing. Extant studies also fall short in examining the role of time and the status of entities generating eWOM in determining the influence of eWOM on decision making. To address this dearth of literature in a context that attracts billions of dollars every year, we investigate the effect of eWOM on venture capital financing. This study entails the challenging task of gathering data from hundreds of ventures along with other sources including VentureXpert, surveys, Google Blogsearch, Lexis-Nexis, and Archive.org.

The key findings of our econometric analysis are that the impact of negative eWOM is greater than is the impact of positive eWOM and that the effect of eWOM on financing decreases with the progress through the financing stages. We also find that the eWOM of popular bloggers helps ventures in getting higher funding amounts and valuations. The empirical model used in this work accounts for inherent selection biases of entrepreneurs and venture capitalists, and we conduct numerous robustness checks for potential issues of endogeneity, selection bias, nonlinearities, and popularity cutoff for blogs. The findings have important implications for entrepreneurs and suggest ways by which entrepreneurs can take advantage of eWOM.
Fighting Fire with Fire: Commercial Piracy and the Role of File Sharing on Copyright Protection Policy for Digital Goods
Authors: Tunca Tunay I. , Wu Qiong
Published: June 2012

In recent years, with the emergence and growth of illegal file sharing on the Internet, individual piracy of digital goods, i.e., consumers making illegal copies on their own rather than relying on purchasing copies from commercial pirates, has stirred substantial controversy. Threatened by this growth, the information goods industry took legal action by suing the file sharing peer-to-peer networks and the consumers who illegally share copyrighted material on these networks. In this paper we demonstrate that each one of these two actions aimed to fight individual piracy can backfire by providing strategic disadvantage to legal publishers of information goods. In particular, we show that in the presence of commercial piracy (i) a higher population of consumers who are capable of individual piracy can increase a legal publisher's profits; and (ii) a higher detection and prosecution rate for individual piracy can reduce a legal publisher's profits. Both effects can be observed in markets where commercial piracy is suppressed because the legal publisher can be coerced to take a price cut to minimize the loss of market share. The latter effect can also be observed in markets with active commercial piracy presence because the legal publisher can be forced to raise prices and concede market share to piracy. Our results suggest that information goods producers may be better off by considering their copyright protection policies concerning individual piracy from a more strategic point of view.
How to undertake a research project and write a scientific paper
Authors: Rhodes M
Published: June 2012

Research and publishing are essential aspects of lifelong learning in a surgical career. Many surgeons, especially those in training, ask for guidance on how they might start a simple project that may lead to a publication. This short paper offers some practical guidelines on the subject.
Prior Funding Approval in Orthopaedics
Authors: Mulligan A , de Roeck N , Jeyaseelan L
Published: June 2012

In November 2009 the Bedfordshire and hertfordshire Priorities forum produced guidance on the referral and surgery thresholds for total hip and knee arthroplasties. This guidance is based on sources from the British orthopaedic Association, the American Association of orthopaedic Surgeons, the department of health and epidemiological studies. The guidance relating to thresholds for surgery focuses on assessment of patient symptomatology against appropriateness criteria as described by Quintana et al. These criteria include pain severity, functional limitation, age, bone quality, surgical risk (ASA [American Society of Anesthesiologists] grade) and attempts at non-surgical management. Quintana et al found that those patients thought to have appropriate criteria prior to surgery have a significantly greater improvement in health-related quality of life scoring systems postoperatively.
It's all about commissioning
Authors: Williams Norman
Published: June 2012

We are being told on an almost daily basis that the European financial position is dire and that implosion is imminent. If Greece does leave the euro as predicted there will be a significant fallout for the rest of the European economy and that includes the UK. Like most surgeons, I am an optimist by nature and feel that no matter how difficult the situation our nation is strong enough to ride the storm and come out stronger. Nevertheless, we may be in for a hard time and the healthcare system will not be immune.
Issues to consider when developing a fluoride strategy
Authors: Batchelor Paul
Published: June 2012

The relatively low levels of caries in the UK call for a reassessment of what strategies are appropriate for using fluorides. To date, the scientific basis for selecting the optimal fluoride strategy is weak. Research on combinations of fluoride agents is limited and the importance of existing fluoride exposure and disease levels has largely been ignored when selecting a strategy. This article describes the issues and proposes a framework that will help ensure that the fluoride agent, namely fluoride toothpaste, which has made the largest contribution to the decline in caries, is the main method for preventing caries throughout life.
3D imaging: the role of cone-beam computed tomography in dentistry: special reference to current guidelines
Authors: Makdissi Jimmy
Published: June 2012

Cone-beam computed tomography (CBCT) is a relatively new modality providing 3D imaging that has become more accessible than ever to dental practice. This brings in new challenges that need to be addressed. This article discusses the role of CBCT in dentistry and highlights the availability of current guidelines.
Validation of a Dosage Individualization Table for Extended-Interval Gentamicin in Neonates
Authors: Dersch-Mills Deonne , Akierman Albert , Alshaikh Belal , Yusuf Kamran
Published: June 2012

BACKGROUND:

Extended-interval aminoglycoside dosing is increasingly used in neonates; however, guidance on how to monitor concentrations and adjust dosages accordingly is limited.

OBJECTIVE:

To prospectively validate the use of a 22-hour gentamicin concentration dosing table for the individualization of extended-interval dosing in the neonatal population by examining the peak and trough concentrations achieved through its use.

METHODS:

A prospective observational study was carried out on gentamicin concentrations achieved using a 22-hour post–first-dose gentamicin concentration dosing table for determining dosing intervals in neonates. Neonates (N = 104) in the first week of life, gestational age 23 weeks to full term, in level II and III neonatal intensive care units were included. Neonates were given gentamicin 5 mg/kg intravenously; a table using 22-hour post-first-dose gentamicin concentrations was then used to individualize dosing intervals. Pre- and post-serum gentamicin concentrations on the dosing interval indicated were measured with the second or third doses and used to calculate the peak and trough concentrations achieved.

RESULTS:

Use of the 22-hour post-first-dose gentamicin concentration dosing table resulted in dosing intervals that provided appropriate peak (mean 10.55 mg/L) and trough (mean 0.75 mg/L) concentrations (with second or third doses) in all neonates. All patients had trough concentrations less than 2 mg/L, and 73% had a trough concentration less than 1 mg/L. No peak concentrations were less than 5 mg/L, 82% of patients had a peak concentration from 5 to 12 mg/L, and the remaining 18% had concentrations from 12.1 to 16 mg/L. Peak and trough concentrations were similar across all gestational ages.

CONCLUSIONS:

Use of a 22-hour post-first-dose gentamicin concentration dosing table to individualize extended-interval gentamicin dosages in neonates resulted in appropriate peak and trough concentrations in all neonates studied. Use of this table will result in appropriate extended-interval aminoglycoside dosages in neonates early in treatment, using a single serum concentration.
Laboratory automation based on flow techniques
Authors: Cerdà Víctor , Avivar Jessica , Cerdà Amalia
Published: June 2012

Flow techniques have undoubtedly aroused special interest in relation to many other automatic methodologies of analysis. Ever since segmented flow analysis (SFA) was developed by Skeggs in 1957, flow techniques have been in continuous evolution toward new develop-ments. There is no solid argument in favor of using any particular flow technique separately; rather, substantial advantages can be derived from their combination. Since flow-based methods are nonseparative tools, the advantages of combining flow techniques with separation techniques are noteworthy. High selectivity can be achieved by coupling them with liquid chromatography (LC), gas chromatography (GC), solid-phase extraction (SPE), or capillary electrophoresis (CE). Thus, a detailed description of flow techniques, their evolution, their hyphenation advantages, and a critical comparison between current developed methods exploiting flow techniques aimed at solving present analytical needs are reviewed in this article.
Bifunctional antioxidant enzyme mimics of albumin-binding salphen Schiff-base metal complexes
Authors: Yin Xiao-Chun , Li Xiao-Xiao , Wang Rong-Min , Li Gang , He Yu-Feng
Published: June 2012

New kinds of bifunctional antioxidant enzyme mimics were prepared, and their superoxide anion radical (O2
•–) and hydroxyl radical (•OH) scavenging activity was investigated. These conjugates were prepared by binding insoluble salphen [N,N-(phenylene)salicylidene] Schiff-base metal complexes (HO-salphen-M, M = Co, Mn, Cu) with bovine serum albumin (BSA). They were characterized by UV–vis spectra, circular dichroism (CD), and native polyacrylamide gel electrophoresis (PAGE). It showed that the binding mode was an axial coordination between HO-salphen-Co and amino acid residue of BSA. The structure of BSA was maintained when the binding amount of HO-salphen-Co was less than 10. After combining HO-salphen-Co into BSA, the low solubility of HO-salphen-Co was overcome, and the O2
•– and •OH scavenging activity of BSA was improved two orders of magnitude. In similar inhibitory value, the scavenging rate of salphen-Co20@BSA was far higher than -others. The scavenging activity of different proportion salphen-Co@BSA was salphen-Co20@BSA > salphen-Co10@BSA > salphen-Co5@BSA > salphen-Co2@BSA. But salphen-Cu@BSA and salphen-Mn@BSA did not show •OH scavenging activity.
A Solid-Cladding/Liquid-Core/Liquid-Cladding Sandwich Optical Waveguide for the Study of Dynamic Extraction of Dye by Ionic Liquid BmimPF6
Authors: Chen Xuwei , Sakurazawa Atsushi , Sato Kiichi , Tsunoda Kin-Ichi , Wang Jianhua
Published: June 2012

We present a sandwich liquid-core waveguide for the study of the dynamic extraction of dye molecules by ionic liquid (IL). The incident light was introduced into the core of the IL phase directly via a fused silica prism to form total reflection at the IL/cladding interface. The changes in light intensity and absorbance spectra over time were monitored during the extraction process by maintaining an optical focus on the IL/water interface. The dynamic extraction of the dye Eriochrome Black-T (EBT) by the IL 1-n-butyl-3-methylimidazolium hexafluorophosphate (BmimPF6) at different concentrations and various pH conditions was investigated. The results indicated that the accumulation of the dye at the IL/water interface and the dynamic extraction of the dye into the IL phase both contributed to the increase in absorbance. The increased signal along with the increase in pH suggests that electrostatic interaction might be the main driving force for the extraction of EBT by BmimPF6, and the micro-circumstance provided by IL also has a decisive effect on the characteristics of the spectra recorded by the waveguide system.
Proposed supramolecular structure of lignin in softwood tracheid compound middle lamella regions
Authors: Terashima Noritsugu , Yoshida Masato , Hafrén Jonas , Fukushima Kazuhiko , Westermark Ulla
Published: June 2012

The structure of lignin in the compound middle lamella (CML) of softwood tracheids differs from that in the secondary wall (SW) in regard to the content of condensed structures (5-5′-biphenyl, dibenzodioxocin and 4-O-5′-diphenyl ether). In an early stage of cell wall formation, random coarse networks composed of thin cellulose microfibrils (CMFs), hemicelluloses, and pectin are formed in the CML, then globular p-hydroxyphenyl/guaiacyl lignin (HG-lignin) is deposited quickly into the network. The globular lignin is assumed to be a micellar aggregate of oligolignols folded at the β-O-4 bond with their phenolic ends on the outer part of the aggregate. When 3D clusters of the globules are deposited on the preformed network of polysaccharides, further growth of the oligolignols by endwise addition of new monolignols is spatially limited, so frequent condensation occurs between growing aromatic ends of adjacent HG-oligolignols within the globule and between the wide contact boundaries of the 3D clustered globules to produce a highly condensed supramolecule in CML. In SW, the folded G-oligolignols are deposited slowly in the narrow tubular space surrounding thick CMFs coated with hemicelluloses. Condensation occurs mostly between adjacent growing ends of the oligolignols within the tubular aggregates. Spatial regulation of condensation of folded polylignols is one of the factors producing a different supramolecular structure for CML lignin than for SW lignin.
Experimental Bend Tests to Study Mechanical Descaling of Hot-Rolled Steel Rod
Authors: Yang Wengai , Li YaoHou , Sellars Christopher Michael
Published: June 2012

Simple cantilever bend testing to assess mechanical descaling of industrial hot-rolled steel rods has been developed and analysed. This test method has no contact damage to the scale, and produces a range of strains along the rod, which always include those for scale behaviour from crack initiation to complete spallation. A series of methods has been used to assess the variation of the plastic strain along the bent rods and the results have been compared with finite element modelling. Using a cyclone scanner for these measurements provides an accurate and efficient testing procedure. To compare with industrial practice, constrained bending around cylinders was also carried out.
Experimental Study of Thermal Contact Conductance Based on Heat-Transfer Theory with Variable Thermal Conductivity
Authors: Wang Zong Ren , Yang Jun , Yang Mingyuan , Zhang Weifang
Published: June 2012

To calculate the interface temperature drop ΔT during the thermal contact conductance (TCC) testing, an optimization computing method based on the one-dimensional steady heat-transfer theory with variable thermal conductance is proposed in this paper. This method takes into account the physical process of heat transfer adequately, which can calculate the temperature drop (ΔT) accurately. Besides, a practical engineering example is utilized to demonstrate the applicability of the proposed approach. By using the optimization computing method along with traditional linear fitting method, the testing values of TCC obtained from the interfaces of the structural materials GH4169 and K417 used in aero-engines are studied and compared. The results show that there are large errors and poor stability in the traditional linear fitting method, and the relative errors of these two methods vary from about 3 % to 17 %.
A Gauge Study for Dynamic Light Scattering and Differential Mobility Analyzer Instruments
Authors: Wang F. K. , Chern H. L. , Yu T. C.
Published: June 2012

This paper presents the performance of dynamic light scattering (DLS) and differential mobility analyzer (DMA) instruments in measuring nanoparticle size data using a gauge repeatability and reproducibility (GR&R) study based on the mixed model. The adequacy of the measurement process was evaluated using a measure of %GR&R with its confidence interval. The results show that the performance of the DMA instrument is superior to that of the DLS with regard to all variance components of a GR&R study. However, both instruments performed poorly in terms of %GR&R. Therefore, the part and measurement system require further improvement. Using these empirical study applications, this research promotes and maintains measurement quality through procedure analysis.
Reliability Evaluation of Failure Data with Poor Information
Authors: Xia Xintao
Published: June 2012

For costly and dangerous experiments, growing attention has been paid to the problem of the reliability of failure data with small sample sizes. The existing reliability theory relies on a given probability distribution, such as the Weibull distribution and the exponential distribution; thus it is ineffective if the probability distribution is unknown. This paper proposes the grey bootstrap method for the reliability analysis of very few failure data with a known or unknown probability distribution. The grey bootstrap method can be employed to generate many simulated data with few data outputted by a population, as well as to imitate the probability distribution of this population. The experimental investigation shows that the grey bootstrap method is effective in analyzing reliability with small sample sizes without any prior information of the probability distribution.
Correlation of Flow Number with Stiffness Obtained from Dynamic Shear Rheometer Testing of Extracted Binder from Asphalt Concrete Containing Recycled Asphalt Pavement
Authors: Apeagyei Alex K. , Diefenderfer Stacey D.
Published: June 2012

This paper describes the results of a study that used the flow number (FN) test to evaluate the rutting susceptibility of asphalt concrete (AC) mixtures containing recycled asphalt pavement (RAP). The study compared the rut depths determined using an asphalt pavement analyzer (APA) (APA rut depth) with binder stiffness test data obtained with a dynamic shear rheometer. Both APA rut depths and binder stiffness are used to evaluate the rutting susceptibility of AC mixtures in Virginia. However, recent studies suggest that the results of the FN test might correlate better with field rutting than most existing rut tests. In addition, because currently almost all AC mixtures produced in Virginia contain RAP, extraction and recovery (ER) tests are required to obtain binder for testing. Therefore, another objective of the study was to determine whether the correlation between FN and the stiffness of recovered asphalt binders would allow the FN test to be used as a surrogate for the recovered binder stiffness. For the mixtures evaluated, the APA rut depth ranged from 0.61 to 1.99 mm, the FN from about 700 to 7500 cycles, and the binder stiffness from 1.637 to 8.498 kPa. The results show that FN was positively correlated with binder stiffness (r = 0.8507, p < 0.0001) but not correlated with APA rut depth (r = −0.2666, p = 0.3010). The results also show that APA rut depth and binder stiffness were not correlated (r = 0.01829, p = 0.944). The study concluded that FN is sensitive to binder stiffness for the mixtures considered. This suggests that the FN test could be used as a new approach for evaluating the effect of RAP on asphalt mixtures and thereby replace or minimize the use of binder ER test methods.