bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance analysis of RTS/CTS scheme in WLAN with the impact of bit errors
Authors: Peng Xiangyu , Jiang Letian , Xu Guozhi 
Published: November 2010

ABSTRACTTo estimate the system performance of RTS/CTS scheme in an error‐prone WLAN channel, this paper proposes a new three‐dimensional Markov model, which considers the impact of bit error on all kinds of frames, and both station short retry limit and long retry limit. The system performance parameters including saturation throughput, packet drop probability, drop time, and average delay are derived using the new Markov model. By comparing the numerical results with simulation results, the model is proved to be more accurate than previous work. The numerical results show that the channel bit error rate has a significant impact not only on system performance, but also on the sensitivity of other system parameters including network scale, channel data rate, and packet length. Copyright © 2010 John Wiley & Sons, Ltd.
Recursion: what is it, who has it, and how did it evolve?
Authors: Coolidge Frederick L. , Overmann Karenleigh A. , Wynn Thomas 
Published: November 2010

AbstractRecursion is a topic of considerable controversy in linguistics, which stems from its varying definitions and its key features, such as its universality, uniqueness to human language, and evolution. Currently, there appear to be at least two common senses of recursion: (1) embeddedness of phrases within other phrases, which entails keeping track of long‐distance dependencies among phrases and (2) the specification of the computed output string itself, including meta‐recursion, where recursion is both the recipe for an utterance and the overarching process that creates and executes the recipes. There are also at least two evolutionary scenarios for the adaptive value of recursion in human language. The gradualist position posits precursors, such as animal communication and protolanguages, and holds that the selective purpose of recursion was for communication. The saltationist position assumes no gradual development of recursion and posits that it evolved for reasons other than communication. In the latter view, some heritable event associated with a cognitive prerequisite of language, such as Theory of Mind or working memory capacity, allowed recursive utterances. Evolutionary adaptive reasons for recursive thoughts were also proffered, including diplomatic speech, perlocutionary acts, and prospective cognitions. WIREs Cogni Sci 2011 2 547–554 DOI: 10.1002/wcs.131This article is categorized under:

Linguistics > Evolution of Language
Clipless Cholecystectomy: Which Sealer Should be Used?
Authors: Kavlakoglu Burak , Pekcici Recep , Oral Suleyman 
Published: November 2010

AbstractBackgroundThe use of the Harmonic Scalpel (HS) for cystic duct ligation began with little data about its efficacy or safety. On the other hand, there is not any literature available about the use of PlasmaKinetic Sealer (PK) for closing the cystic duct in laparoscopic cholecystectomy (LC). Therefore, this study was designed to compare the efficacy and safety of HS and PK for achieving safe closure of the cystic ducts after LC.MethodsNinety patients with symptomatic gallstone disease were enrolled in this prospective case control study. The patients were operated with laparoscopic technic and divided into three groups (n = 30) randomly. After the dissection of Calot’s triangle, proximal cystic ducts on common bile ducts were sealed with single surgical clips (SC) in all groups, and in the first group, distal of the cystic ducts also was sealed with single SC and the gallbladders were removed with SC. In the second and third groups, distal of the cystic ducts were sealed with HS and PK, respectively. The gallbladders were removed as sealed cystic ducts with HS and PK. Then, gallbladders were connected to a transducer set and increasing pressure with saline was applied. The bursting pressures of gallbladders were measured and differences between the groups were calculated by using Student’s t test. The value of P < 0.05 was accepted as significant.ResultsIn this study, the mean cystic duct bursting pressures were 332.46 ± 4.62 mmHg with SC, 326.56 ± 4.53 mmHg with PK, and 343.06 ± 4.28 mmHg with HS. Differences of the mean cystic duct bursting pressures between the groups were indicated the superior results of HS.ConclusionsThe results of this study indicated that HS is more effective than PK and as safe and effective as SC for cystic duct closure.
Measures to Prevent Surgical Site Infections: What Surgeons (Should) Do
Authors: Diana Michele , Hübner Martin , Eisenring Marie‐Christine , Zanetti Giorgio , Troillet Nicolas , Demartines Nicolas 
Published: November 2010

AbstractBackgroundThe present study was designed to evaluate surgeons’ strategies and adherence to preventive measures against surgical site infections (SSIs).Materials and methodsAll surgeons participating in a prospective Swiss multicentric surveillance program for SSIs received a questionnaire developed from the 2008 National (United Kingdom) Institute for Health and Clinical Excellence (NICE) clinical guidelines on prevention and treatment of SSIs. We focused on perioperative management and surgical technique in hernia surgery, cholecystectomy, appendectomy, and colon surgery (COL).ResultsForty‐five of 50 surgeons contacted (90%) responded. Smoking cessation and nutritional screening are regularly propagated by 1/3 and 1/2 of surgeons, respectively. Thirty‐eight percent practice bowel preparation before COL. Preoperative hair removal is routinely (90%) performed in the operating room with electric clippers. About 50% administer antibiotic prophylaxis within 30 min before incision. Intra‐abdominal drains are common after COL (43%). Two thirds of respondents apply nonocclusive wound dressings that are manipulated after hand disinfection (87%). Dressings are usually changed on postoperative day (POD) 2 (75%), and wounds remain undressed on POD 2–3 or 4–5 (36% each).ConclusionsSurgeons’ strategies to prevent SSIs still differ widely. The adherence to the current NICE guidelines is low for many procedures regardless of the available level of evidence. Further research should provide convincing data in order to justify standardization of perioperative management.
Simplified Alternative to the TRISS Method for Resource‐Constrained Settings
Authors: Nakahara Shinji , Ichikawa Masao , Kimura Akio 
Published: November 2010

AbstractBackgroundWe developed simple methods of risk adjustment for evaluating the quality of injury care (predicting survival probabilities of the injured) by fully utilizing routinely collected data in injury surveillance and clinical practices. Widely used methods of risk adjustment require additional data that are difficult to collect in resource‐constrained settings.MethodsWe developed logistic regression models that predict survival using data obtained from 9,840 victims aged 15 years or older with blunt traumatic injuries who were registered in the Japan Trauma Data Bank, Japan’s national trauma registry, between January 2004 and December 2007. The models included three predictors: age, an anatomical injury severity parameter such as a simplified severity categorization (minor, moderate, and severe) described in the Injury Surveillance Guidelines, and a physiological status parameter. The models’ abilities to predict survival probabilities were evaluated using the area under the receiver‐operating characteristic curve (AUROCC).ResultsThe simplified three‐predictor models showed good performance with the AUROCC ranging from 0.86 to 0.94. In particular, the models with a consciousness level indicator as a physiological parameter showed a high AUROCC, ranging from 0.93 to 0.94, which was not much different from the performance of the widely used method that shows an AUROCC of 0.96.ConclusionsSimplified methods of risk adjustment that require only routinely collected data will facilitate evaluation and improvement in the quality of injury care in resource‐constrained low‐ and middle‐income countries, where injuries are a growing public health concern.
Oxidative Stability of Marine Phospholipids in the Liposomal Form and Their Applications
Authors: Henna Lu F. S. , Nielsen N. S. , Timm‐Heinrich M. , Jacobsen C. 
Published: November 2010

AbstractMarine phospholipids (MPL) have attracted a great deal of attention recently as they are considered to have a better bioavailability, a better resistance towards oxidation and a higher content of eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) than oily triglycerides (fish oil) from the same source. Due to their tight intermolecular packing conformation at thesn‐2 position and their synergism with α‐tocopherol present in MPL extracts, they can form stable liposomes which are attractive ingredients for food or feed applications. However, MPL are still susceptible to oxidation as they contain large amounts polyunsaturated fatty acids and application of MPL in food and aquaculture industries is therefore a great challenge for researchers. Hence, knowledge on the oxidative stability of MPL and the behavior of MPL in food and feed systems is an important issue. For this reason, this review was undertaken to provide the industry and academia with an overview of (1) the stability of MPL in different forms and their potential as liposomal material, and (2) the current applications and future prospects of MPL in both food and aquaculture industries with special emphasis on MPL in the liposomal form.
Modulation of innate immunity by African Trypanosomes
Authors: PAULNOCK DONNA M. , FREEMAN BAILEY E. , MANSFIELD JOHN M. 
Published: November 2010

SUMMARYThe experimental studies ofBruceigroup trypanosomes presented here demonstrate that the balance of host and parasite factors, especially IFN-γGPI-sVSG respectively, and the timing of cellular exposure to them, dictate the predominant MP and DC activation profiles present at any given time during infection and within specific tissues. The timing of changes in innate immune cell functions following infection consistently support the conclusion that the key events controlling host resistance occur within a short time following initial exposure to the parasite GPI substituents. Once the changes in MP and DC activities are initiated, there appears little that the host can do to reverse these changes and alter the final outcome of these regulatory events. Instead, despite the availability of multiple innate and adaptive immune mechanisms that can control parasites, there is an inability to control trypanosome numbers sufficiently to prevent the emergence and establishment of virulent trypanosomes that eventually kill the host. Overall it appears that trypanosomes have carefully orchestrated the host innate and adaptive immune response so that parasite survival and transmission, and alterations of host immunity, are to its ultimate benefit.
An empirical study of the expressiveness of the functional basis
Authors: Caldwell Benjamin W. , Sen Chiradeep , Mocko Gregory M. , Summers Joshua D. 
Published: November 2010

AbstractFunction models are frequently used in engineering design to describe the technical functions that a product performs. This paper investigates the use of the functional basis, a function vocabulary developed to aid in communication and archiving of product function information, in describing consumer products that have been decomposed, analyzed, modeled functionally, and stored in a Web-based design repository. The frequency of use of function terms and phrases in 11 graphical and 110 list-based representations in the repository is examined and used to analyze the organization and expressiveness of the functional basis and function models. Within the context of reverse engineering, we determined that the modeling resolution provided by the hierarchical levels, especially the tertiary level, is inadequate for function modeling; the tertiary terms are inappropriate for capturing sufficient details desired by modelers for archiving and reuse, and there is a need for a more expressive flow terms and flow qualifiers in the vocabulary. A critical comparison is also presented of two representations in the design repository: function structures and function lists. The conclusions are used to identify new research opportunities, including the extension of the vocabulary to incorporate flow qualifiers in addition to more expressive terms.
Making the case for plant diversity
Authors: Smith Paul , Dickie John , Linington Simon , Probert Robin , Way Michael 
Published: November 2010

AbstractThe Millennium Ecosystem Assessment estimates that between 60,000 and 100,000 plant species are threatened with extinction–equivalent to around one-quarter of the total number of known plant species. Why should we care? There are a number of reasons. The first is that these plants may be useful to us in unknown ways. Secondly, ecology has taught us that resilience is found in diversity. Thirdly, we should be saving plant species from extinction because we can–there is no technological reason why any plant species should become extinct. Where we can't protect and manage plant diversity in situ, we should be employing ex situ conservation techniques, ranging from seed banks to habitat restoration. The Millennium Ecosystem Assessment describes such interventions as ‘techno-gardening’. This is not an abstract concept–it is already a reality in the majority of man-managed landscapes. In this context the perception of ex situ conservation as simply a back-up strategy for in situ conservation is mistaken. We are all involved in ex situ conservation to some degree, from cultivating our back gardens, to farming, to management of protected areas. Ex situ conservation should be seen as a complementary approach to in situ conservation and on the same spectrum. Kew's Millennium Seed Bank Partnership, comprising more than 120 plant science institutions in 50 countries, epitomizes this philosophy in action. We work actively on every seed collection we bank, finding out how useful it is and how we can grow it to enable human innovation, adaptation and resilience. Challenges remain at the policy level; for example, the need to factor-in the value of natural capital to development decision making, and better defining a role for public-sector science. At the technical level, also, there is much to do. Perhaps the greatest technical challenges relate to the restoration and management of complex, self-sustaining habitats or species assemblages. If we are to techno-garden effectively, in order to maintain ecosystem services and sustain biodiversity, then a multidisciplinary approach will be required. Many plant science institutions have recognized this and are becoming engaged increasingly in restoration activities and in situ management. Ultimately, humanity's ability to innovate and adapt is dependent on our having access to the full range of plant species and the alleles they contain.
Impact of internal waves on the spatial distribution of Planktothrix rubescens (cyanobacteria) in an alpine lake
Authors: Cuypers Yannis , Vinçon-Leite Brigitte , Groleau Alexis , Tassin Bruno , Humbert Jean-François 
Published: November 2010

Abstract
The vertical and horizontal distribution of the cyanobacterium, Planktothrix rubescens, was studied in a deep alpine lake (Lac du Bourget) in a 2-year monitoring program with 11 sampling points, and a 24-h survey at one sampling station. This species is known to proliferate in the metalimnic layer of numerous deep mesotrophic lakes in temperate areas, and also to produce hepatotoxins. When looking at the distribution of P. rubescens at the scale of the entire lake, we found large variations (up to 10 m) in the depth of the biomass peak in the water column. These variations were closely correlated to isotherm displacements. We also found significant variations in the distribution of the cyanobacterial biomass in the northern and southern parts of the lake. We used a physical modeling approach to demonstrate that two internal wave modes can explain these variations. Internal waves are generated by wind events, but can still be detected several days after the end of these events. Finally, our 24-h survey at one sampling point demonstrated that the V1H1 sinusoidal motion could evolve into nonlinear fronts. All these findings show that internal waves have a major impact on the distribution of P. rubescens proliferating in the metalimnic layer of a deep lake, and that this process could influence the growth of this species by a direct impact on light availability.
The Human Microbiome and Recurrent Abdominal Pain in Children
Authors: Raza Sabeen , Gibbs Richard , Mandal Debasmita , Qin Xiang , Lynch Susan , Versalovic James , Shulman Robert , Riehle Kevin , Saulnier Delphine , Mistretta Toni-Ann , Petrosino Joseph , Diaz Maria 
Published: November 2010

AbstractThis project explores the nature of the human intestinal microbiome in healthy children and children with recurrent abdominal pain. The overall goal is to obtain a robust knowledge base of the intestinal microbiome in children without evidence of pain or gastrointestinal disease and in those with recurrent abdominal pain (functional abdominal pain (FAP) and FAP associated with changes in bowel habits, i.e., irritable bowel syndrome or IBS). Specific aims include: 1. Characterize the composition of the gut microbiome in healthy children by DNA sequencing. 2. Determine the presence of disease-specific organism signatures of variable gut microbiomes in children with recurrent abdominal pain. 3. Perform functional gut metagenomics by evaluation of whole community gene expression profiles and discovery of disease-specific pathway signatures. Multiple strategies have been deployed to navigate and understand the nature of the intestinal microbiome in childhood. These strategies included 454 pyrosequencing-based strategies to sequence 16S rRNA genes and understand the detailed composition of microbes in healthy and disease groups. Microarray-based hybridization with the PhyloChip and quantitative real-time PCR (qPCR) probes were applied as complementary strategies to gain an understanding of the intestinal microbiome from various perspectives. Data collected and analyzed during the HMP UH2 Demo project, from a set of healthy and IBS children (7-12 yo) may enable the identification of core microbiomes in children, in addition to variable components that may distinguish healthy from diseased pediatric states. Twenty-two children with IBS and twenty-two healthy children were enrolled and analyzed in the UH2 phase of this study. The planned enrollment targets for the UH2/3 phases include 50 healthy children, 50 children with FAP and 50 children with IBS (minimum of 3 time points per child). We are currently analyzing the dataset for the presence of disease-specific signatures in the human microbiome, and correlating these microbial signatures with pediatric health or IBS disease status in addition to IBS subtype (e.g., diarrhea-vs constipation-predominant). In the next phase, whole genome shotgun sequencing and metatranscriptomics will be performed with a subset of children in each group. This study explores the nature of core and variable human microbiome in pre-adolescent healthy children and children with IBS.
Drug resistance against HCV NS3/4A inhibitors is defined by the balance of substrate recognition versus inhibitor binding
Authors: Romano Keith P. , Ali Akbar , Royer William E. , Schiffer Celia A. 
Published: November 2010

Hepatitis C virus infects an estimated 180 million people worldwide, prompting enormous efforts to develop inhibitors targeting the essential NS3/4A protease. Resistance against the most promising protease inhibitors, telaprevir, boceprevir, and ITMN-191, has emerged in clinical trials. In this study, crystal structures of the NS3/4A protease domain reveal that viral substrates bind to the protease active site in a conserved manner defining a consensus volume, or substrate envelope. Mutations that confer the most severe resistance in the clinic occur where the inhibitors protrude from the substrate envelope, as these changes selectively weaken inhibitor binding without compromising the binding of substrates. These findings suggest a general model for predicting the susceptibility of protease inhibitors to resistance: drugs designed to fit within the substrate envelope will be less susceptible to resistance, as mutations affecting inhibitor binding would simultaneously interfere with the recognition of viral substrates.
Superfamily-wide portrait of serine hydrolase inhibition achieved by library-versus-library screening
Authors: Bachovchin Daniel A. , Ji Tianyang , Li Weiwei , Simon Gabriel M. , Blankman Jacqueline L. , Adibekian Alexander , Hoover Heather , Niessen Sherry , Cravatt Benjamin F. 
Published: November 2010

Serine hydrolases (SHs) are one of the largest and most diverse enzyme classes in mammals. They play fundamental roles in virtually all physiological processes and are targeted by drugs to treat diseases such as diabetes, obesity, and neurodegenerative disorders. Despite this, we lack biological understanding for most of the 110+ predicted mammalian metabolic SHs, in large part because of a dearth of assays to assess their biochemical activities and a lack of selective inhibitors to probe their function in living systems. We show here that the vast majority (> 80%) of mammalian metabolic SHs can be labeled in proteomes by a single, active site-directed fluorophosphonate probe. We exploit this universal activity-based assay in a library-versus-library format to screen 70+ SHs against 140+ structurally diverse carbamates. Lead inhibitors were discovered for ∼40% of the screened enzymes, including many poorly characterized SHs. Global profiles identified carbamate inhibitors that discriminate among highly sequence-related SHs and, conversely, enzymes that share inhibitor sensitivity profiles despite lacking sequence homology. These findings indicate that sequence relatedness is not a strong predictor of shared pharmacology within the SH superfamily. Finally, we show that lead carbamate inhibitors can be optimized into pharmacological probes that inactivate individual SHs with high specificity in vivo.