bluuebunny/crossref_metadata_2025 huggingface dataset:
Histo-anatomical leaf variations related to depth in Posidonia oceanica
Authors: Nicastro Silvia , Innocenti Anna M. , Passalacqua Nicodemo G.
Published: February 2015

The purpose of our study is to explore the acclimation of Neptune seagrass (Posidonia oceanica (L.) Delile) to depth by characterising the histo-anatomical leaf modifications. P. oceanica is the dominant seagrass and main habitat constructor of seagrass meadows in the Mediterranean Sea. Meadows play an important biological and ecological role in marine ecosystems, serving as a habitat for a large diversity of species and an efficient erosion protection system for our coasts. Seagrasses are very sensitive to change in light availability and small changes can have significant effects on growth, abundance and distribution. In this study, we analyse changes in P. oceanica leaves collected at –5 m, –15 m and –25 m depth in the Cirella meadow (Tyrrhenian coast, Southern Italy) in order to determine their depth-related histo-anatomical variation. Two main changes were observed at depth: (1) photosynthetic epidermal cells showed smaller chloroplasts but in the same number; and (2) leaves showed smaller epidermal cells and in greater number. Hence, the photosynthetic surface of P. oceanica leaves remains the same at different depths but pigment absorption efficiency can be significantly enhanced with depth. This response supports the differential photoacclimatory response of seagrasses with respect to terrestrial plants previously documented. Mesophyll cells are smaller with depth and more numerous, with a consequent increase in leaf density. The number of vascular bundles also increases, which allows improved functional efficiency of the transport system and solute exchange. Our study is a new contribution to the morpho-functional implications of the histo-anatomy of P. oceanica.
The likelihood of ignition of dry-eucalypt forest litter by firebrands
Authors: Ellis P. F. M.
Published: February 2015

Ignition probability of litter of dry-eucalypt forest by standard flaming and glowing firebrand samples was tested in a wind tunnel. Standard flaming firebrands were sections of bamboo sate stick 50 mm long, and flamed for ~9 s in still air. Standard glowing samples were sections of shed bark of Eucalyptus globulus 50 mm long, 15 mm wide and ~2 mm in thickness. These were burnt at their terminal velocities and at deposition had a mean mass of 0.2 g and would remain glowing for 2.5 min in wind. Ignition was tested using air speeds of zero, 1 and 2 m s–1, and oven-dried fuel moisture contents between 4 and 21%. For flaming samples, ignition probability was insensitive to variation in fuel and airflow characteristics and was a function of wind (no wind or wind) and fuel moisture content. For glowing samples, ignition probability was a function of fuel moisture content and wind speed. The models confirm the dominating influence of fuel moisture, are consistent with expert observations in the field and provide a practical measure of ignition likelihood by firebrands. It is argued that airflow turbulence and relative humidity are potentially significant for ignition by glowing firebrands.
Identity as space
Authors: Goutsos Dionysis , Polymeneas George
Published: February 2015

The paper studies the textual, discursive and social practices of the Greek “aganaktismeni” (indignados) movements, which mainly took place in the public gathering of tens of thousands of Greeks in Syntagma Square, outside the Greek parliament from May to August 2011. Data come from multiple sources, including the General Assembly proceedings and resolutions, while a linguistically-informed approach is followed, which combines Critical Discourse Analysis concepts with corpus linguistic methods. It is argued that the Syntagma protests generated a new context in Greek politics, by introducing new genres and the innovative articulation of already existing discourses. It was also found that social/political identities and social/public space were co-articulated, since the identity of the movement was crucially constructed in terms of space.
The Association between School Bonding and Smoking Amongst Chilean Adolescents
Authors: Gaete Jorge , Montgomery Alan , Araya Ricardo
Published: February 2015

Background

The objective of the research was to study the association between school bonding dimensions (school commitment and school attachment) and current adolescent smoking in Chile, controlling for confounding variables using the fifth Chilean School Population National Substance Use Survey, 2003 (CHSS-2003) data set.

Methods

The CHSS-2003 is a stratified cross-sectional survey that gathers information about personal, familial, peer, and school factors and cigarette use using a self-reported questionnaire. Complete data from 21,956 adolescent students for all the variables of interest were used in the analyses. An exploratory factor analysis (EFA) was performed in order to explore the construct validity of the questionnaire and create the main exposure and potential confounding variables. Multivariable logistic regression analyses were undertaken to study the association between school bonding and smoking.

Results

The construct validity of the school attachment and school commitment scales was mainly supported by the EFA. Multivariable analyses showed strong evidence that, after adjusting for factors from different domains, school commitment (student's good grades and school attendance) appears to have a clear inverse association with current smoking (odds ratio [OR] = 0.46, 95% confidence interval [CI]: 0.38–0.56). On the other hand, school attachment (their feelings towards their school and their teachers) was not associated with adolescent smoking (OR = 1.16, 95% CI: 0.88–1.53).

Conclusions

School commitment was strongly associated with current smoking. It is important to further study this variable with the aim of ascertaining whether or not interventions that improve school commitment may prevent or reduce smoking amongst adolescent students.
The use of Technology in Participant Tracking and Study Retention: Lessons Learned from a Clinical Trials Network Study
Authors: Mitchell Shannon Gwin , Schwartz Robert P. , Alvanzo Anika A. H. , Weisman Monique S. , Kyle Tiffany L. , Turrigiano Eva M. , Gibson Martha L. , Perez Livangelie , McClure Erin A. , Clingerman Sara , Froias Autumn , Shandera Danielle R. , Walker Robrina , Babcock Dean L. , Bailey Genie L. , Miele Gloria M. , Kunkel Lynn E. , Norton Michael , Stitzer Maxine L.
Published: February 2015

Background

The growing use of newer communication and Internet technologies, even among low-income and transient populations, require research staff to update their outreach strategies to ensure high follow-up and participant retention rates. This paper presents the views of research assistants on the use of cell phones and the Internet to track participants in a multisite randomized trial of substance use disorder treatment.

Methods

Preinterview questionnaires exploring tracking and other study-related activities were collected from 21 research staff across the 10 participating US sites. Data were then used to construct a semistructured interview guide that, in turn, was used to interview 12 of the same staff members. The questionnaires and interview data were entered in Atlas.ti and analyzed for emergent themes related to the use of technology for participant-tracking purposes.

Results

Study staff reported that most participants had cell phones, despite having unstable physical addresses and landlines. The incoming call feature of most cell phones was useful for participants and research staff alike, and texting proved to have additional benefits. However, reliance on participants’ cell phones also proved problematic. Even homeless participants were found to have access to the Internet through public libraries and could respond to study staff e-mails. Some study sites opened generic social media accounts, through which study staff sent private messages to participants. However, the institutional review board (IRB) approval process for tracking participants using social media at some sites was prohibitively lengthy. Internet searches through Google, national paid databases, obituaries, and judiciary Web sites were also helpful tools.

Conclusions

Research staff perceive that cell phones, Internet searches, and social networking sites were effective tools to achieve high follow-up rates in drug abuse research. Studies should incorporate cell phone, texting, and social network Web site information on locator forms; obtain IRB approval for contacting participants using social networking Web sites; and include Web searches, texting, and the use of social media in staff training as standard operating procedures.
Native Language Influence on the Distributive Effect in Producing Second Language Subject–Verb Agreement
Authors: Wei Xiaoyan , Chen Baoguo , Liang Lijuan , Dunlap Susan
Published: February 2015

Three experiments were conducted to investigate the distributive effect when producing subject–verb agreement in English as a second language (L2) when the participant's first language either does or does not require subject–verb agreement. Both Chinese–English and Uygur–English bilinguals were included in Experiment 1. Chinese has no required subject–verb agreement, whereas Uygur does. Results showed that the distributive effect was observed in Uygur–English bilinguals but not in Chinese–English bilinguals, indicating that this particular first language (L1) syntactic feature is one significant factor affecting the distributive effect in the production of subject–verb agreement in L2. Experiment 2 further investigated the matter by choosing Chinese–English participants with higher L2 proficiency. Still, no distributive effect was observed, suggesting that the absence of distributive effect in Chinese–English bilinguals in Experiment 1 was not due to low proficiency in the target language. Experiment 3 changed the way the stimuli were presented, highlighting the singular or distributive nature of the subject noun phrases, and the distributive effect was observed in Chinese–English bilinguals. Altogether, the results show that the L1 syntactic feature of subject–verb agreement is one significant factor affecting the distributive effect in the production of subject–verb agreement in L2. More specifically, distributive effects rarely occur in L2 when L1 has no requirement on subject–verb agreement, whereas distributive effects are more likely to occur in L2 when the L1 also has required subject–verb agreement.
Topology of quadrature domains
Authors: Lee Seung-Yeop , Makarov Nikolai
Published: February 2015

We address the problem of topology of quadrature domains, namely we give upper bounds on the connectivity of the domain in terms of the number of nodes and their multiplicities in the quadrature identity.
Primes in intervals of bounded length
Authors: Granville Andrew
Published: February 2015

The infamous twin prime conjecture states that there are infinitely many pairs of distinct primes which differ by

2
2

. Until recently this conjecture had seemed to be far out of reach with current techniques. However, in April 2013, Yitang Zhang proved the existence of a finite bound

B
B

such that there are infinitely many pairs of distinct primes which differ by no more than

B
B

. This is a massive breakthrough, making the twin prime conjecture look highly plausible, and the techniques developed help us to better understand other delicate questions about prime numbers that had previously seemed intractable.

Zhang even showed that one can take

B
=
70000000

B = 70000000

. Moreover, a co-operative team, Polymath8, collaborating only online, had been able to lower the value of

B
B

to

4680

{4680}

. They had not only been more careful in several difficult arguments in Zhang’s original paper, they had also developed Zhang’s techniques to be both more powerful and to allow a much simpler proof (and this forms the basis for the proof presented herein).

In November 2013, inspired by Zhang’s extraordinary breakthrough, James Maynard dramatically slashed this bound to

600
600

, by a substantially easier method. Both Maynard and Terry Tao, who had independently developed the same idea, were able to extend their proofs to show that for any given integer

m
≥
1

m\geq 1

there exists a bound

B
m

B_m

such that there are infinitely many intervals of length

B
m

B_m

containing at least

m
m

distinct primes. We will also prove this much stronger result herein, even showing that one can take

B
m

=

e

8
m
+
5

B_m=e^{8m+5}

.

If Zhang’s method is combined with the Maynard–Tao setup, then it appears that the bound can be further reduced to

246
246

. If all of these techniques could be pushed to their limit, then we would obtain

B
B

(

=

B
2

=B_2

)

=
12

=12

(or arguably to

6
6

), so new ideas are still needed to have a feasible plan for proving the twin prime conjecture.

The article will be split into two parts. The first half will introduce the work of Zhang, Polymath8, Maynard and Tao, and explain their arguments that allow them to prove their spectacular results. The second half of this article develops a proof of Zhang’s main novel contribution, an estimate for primes in relatively short arithmetic progressions.
Integral representation and uniform limits for some Heckman-Opdam hypergeometric functions of type \textsl{BC}
Authors: Rösler Margit , Voit Michael
Published: February 2015

The Heckman-Opdam hypergeometric functions of typeBCextend classical Jacobi functions in one variable and include the spherical functions of non-compact Grassmann manifolds over the real, complex or quaternionic numbers. There are various limit transitions known for such hypergeometric functions. In the present paper, we use an explicit form of the Harish-Chandra integral representation as well as an interpolated variant in order to obtain two limit results, each of them for three continuous classes of hypergeometric functions of typeBCwhich extend the group cases over the fieldsR,C,H.\mathbb R, \mathbb C, \mathbb H.These limits are distinguished from the known results by explicit and uniform error bounds. The first limit realizes the approximation of the spherical functions of infinite dimensional Grassmannians of fixed rank; here hypergeometric functions of type A appear as limits. The second limit is a contraction limit towards Bessel functions of Dunkl type.
Identifying homelessness using health information exchange data
Authors: Zech John , Husk Gregg , Moore Thomas , Kuperman Gilad J , Shapiro Jason S
Published: February 2015

Background Homeless patients experience poor health outcomes and consume a disproportionate amount of health care resources compared with domiciled patients. There is increasing interest in the federal government in providing care coordination for homeless patients, which will require a systematic way of identifying these individuals.

Objective We analyzed address data from Healthix, a New York City–based health information exchange, to identify patterns that could indicate homelessness.

Methods Patients were categorized as likely to be homeless if they registered with the address of a hospital, homeless shelter, place of worship, or an address containing a keyword synonymous with “homelessness.”

Results We identified 78 460 out of 7 854 927 Healthix patients (1%) as likely to have been homeless over the study period of September 30, 2008 to July 19, 2013. We found that registration practices for these patients varied widely across sites.

Conclusions The use of health information exchange data enabled us to identify a large number of patients likely to be homeless and to observe the wide variation in registration practices for homeless patients within and across sites. Consideration of these results may suggest a way to improve the quality of record matching for homeless patients. Validation of these results is necessary to confirm the homeless status of identified individuals. Ultimately, creating a standardized and structured field to record a patient’s housing status may be a preferable approach.
Cost-effectiveness analysis of a hospital electronic medication management system
Authors: Westbrook Johanna I , Gospodarevskaya Elena , Li Ling , Richardson Katrina L , Roffe David , Heywood Maureen , Day Richard O , Graves Nicholas
Published: February 2015

Objective To conduct a cost–effectiveness analysis of a hospital electronic medication management system (eMMS).

Methods We compared costs and benefits of paper-based prescribing with a commercial eMMS (CSC MedChart) on one cardiology ward in a major 326-bed teaching hospital, assuming a 15-year time horizon and a health system perspective. The eMMS implementation and operating costs were obtained from the study site. We used data on eMMS effectiveness in reducing potential adverse drug events (ADEs), and potential ADEs intercepted, based on review of 1 202 patient charts before (n = 801) and after (n = 401) eMMS. These were combined with published estimates of actual ADEs and their costs.

Results The rate of potential ADEs following eMMS fell from 0.17 per admission to 0.05; a reduction of 71%. The annualized eMMS implementation, maintenance, and operating costs for the cardiology ward were A$61 741 (US$55 296). The estimated reduction in ADEs post eMMS was approximately 80 actual ADEs per year. The reduced costs associated with these ADEs were more than sufficient to offset the costs of the eMMS. Estimated savings resulting from eMMS implementation were A$63–66 (US$56–59) per admission (A$97 740–$102 000 per annum for this ward). Sensitivity analyses demonstrated results were robust when both eMMS effectiveness and costs of actual ADEs were varied substantially.

Conclusion The eMMS within this setting was more effective and less expensive than paper-based prescribing. Comparison with the few previous full economic evaluations available suggests a marked improvement in the cost–effectiveness of eMMS, largely driven by increased effectiveness of contemporary eMMs in reducing medication errors.
Harmonizing and extending standards from a domain-specific and bottom-up approach: an example from development through use in clinical applications
Authors: Harris Marcelline R , Langford Laura Heermann , Miller Holly , Hook Mary , Dykes Patricia C , Matney Susan A
Published: February 2015

Objective Currently, the processes for harmonizing and extending standards by leveraging the knowledge within local documentation artifacts are not well described. We describe a collaborative project to develop common information models, terminology bindings, and term definitions based on nursing documentation systems, and carry the findings through to the adoption in standards development organizations (SDOs) and technical implementations in clinical applications.

Materials and Methods Nursing flowsheet documents from six large organizations were analyzed to generate a common information model and terminologies that fully expressed documentation across all systems, and were sufficient for evidence-based decision support, reporting, and analysis.

Results Significant gaps in existing standards were identified. The models and terminologies were submitted to and incorporated by SDOs, are published, implemented, and now serving as a foundation for an eMeasure.

Discussion There are few examples in the literature of success working through the standards development process from a bottom-up perspective. Subsequently, standards do not yet fully address the need for detailed clinical data that enables, for example, decision support as well as a range of reporting and analytic requirements. Recommendations from this project include transparent processes within SDOs, registries that make models and associated terminologies freely available, and coordinated governance processes.

Conclusion We demonstrated the feasibility of using documentation artifacts in a bottom-up approach to develop common models and sets of terms that are complete from the perspective of clinical implementation. Importantly, we demonstrated a process by which a community of practice can contribute to closing gaps in existing standards using SDO processes.
Feasibility and utility of applications of the common data model to multiple, disparate observational health databases
Authors: Voss Erica A , Makadia Rupa , Matcho Amy , Ma Qianli , Knoll Chris , Schuemie Martijn , DeFalco Frank J , Londhe Ajit , Zhu Vivienne , Ryan Patrick B
Published: February 2015

Objectives To evaluate the utility of applying the Observational Medical Outcomes Partnership (OMOP) Common Data Model (CDM) across multiple observational databases within an organization and to apply standardized analytics tools for conducting observational research.

Materials and methods Six deidentified patient-level datasets were transformed to the OMOP CDM. We evaluated the extent of information loss that occurred through the standardization process. We developed a standardized analytic tool to replicate the cohort construction process from a published epidemiology protocol and applied the analysis to all 6 databases to assess time-to-execution and comparability of results.

Results Transformation to the CDM resulted in minimal information loss across all 6 databases. Patients and observations excluded were due to identified data quality issues in the source system, 96% to 99% of condition records and 90% to 99% of drug records were successfully mapped into the CDM using the standard vocabulary. The full cohort replication and descriptive baseline summary was executed for 2 cohorts in 6 databases in less than 1 hour.

Discussion The standardization process improved data quality, increased efficiency, and facilitated cross-database comparisons to support a more systematic approach to observational research. Comparisons across data sources showed consistency in the impact of inclusion criteria, using the protocol and identified differences in patient characteristics and coding practices across databases.

Conclusion Standardizing data structure (through a CDM), content (through a standard vocabulary with source code mappings), and analytics can enable an institution to apply a network-based approach to observational research across multiple, disparate observational health databases.
Dissecting the determinants of malaria chronicity: why within-host models struggle to reproduce infection dynamics
Authors: Childs Lauren M. , Buckee Caroline O.
Published: February 2015

The duration of infection is fundamental to the epidemiological behaviour of any infectious disease, but remains one of the most poorly understood aspects of malaria. In endemic areas, the malaria parasite
Plasmodium falciparum
can cause both acute, severe infections and asymptomatic, chronic infections through its interaction with the host immune system. Frequent superinfection and massive parasite genetic diversity make it extremely difficult to accurately measure the distribution of infection lengths, complicating the estimation of basic epidemiological parameters and the prediction of the impact of interventions. Mathematical models have qualitatively reproduced parasite dynamics early during infection, but reproducing long-lived chronic infections remains much more challenging. Here, we construct a model of infection dynamics to examine the consequences of common biological assumptions for the generation of chronicity and the impact of co-infection. We find that although a combination of host and parasite heterogeneities are capable of generating chronic infections, they do so only under restricted parameter choices. Furthermore, under biologically plausible assumptions, co-infection of parasite genotypes can alter the course of infection of both the resident and co-infecting strain in complex non-intuitive ways. We outline the most important puzzles for within-host models of malaria arising from our analysis, and their implications for malaria epidemiology and control.
Broadband and polarization reflectors in the lookdown,Selene vomer
Authors: Zhao Shulei , Brady Parrish Clawson , Gao Meng , Etheredge Robert Ian , Kattawar George W. , Cummings Molly E.
Published: February 2015

Predator evasion in the open ocean is difficult because there are no objects to hide behind. The silvery surface of fish plays an important role in open water camouflage. Various models have been proposed to account for the broadband reflectance by the fish skin that involve one-dimensional variations in the arrangement of guanine crystal reflectors, yet the three-dimensional organization of these guanine platelets have not been well characterized. Here, we report the three-dimensional organization and the optical properties of integumentary guanine platelets in a silvery marine fish, the lookdown (Selene vomer). Our structural analysis and computational modelling show that stacks of guanine platelets with random yaw angles in the fish skin produce broadband reflectance via colour mixing. Optical axes of the guanine platelets and the collagen layer are aligned closely and provide bulk birefringence properties that influence the polarization reflectance by the skin. These data demonstrate how the lookdown preserves or alters polarization states at different incident polarization angles. These optical properties resulted from the organization of these guanine platelets and the collagen layer may have implications for open ocean camouflage in varying light fields.
Massive migration from the steppe is a source for Indo-European languages in Europe
Authors: Haak Wolfgang , Lazaridis Iosif , Patterson Nick , Rohland Nadin , Mallick Swapan , Llamas Bastien , Brandt Guido , Nordenfelt Susanne , Harney Eadaoin , Stewardson Kristin , Fu Qiaomei , Mittnik Alissa , Bánffy Eszter , Economou Christos , Francken Michael , Friederich Susanne , Pena Rafael Garrido , Hallgren Fredrik , Khartanovich Valery , Khokhlov Aleksandr , Kunst Michael , Kuznetsov Pavel , Meller Harald , Mochalov Oleg , Moiseyev Vayacheslav , Nicklisch Nicole , Pichler Sandra L. , Risch Roberto , Rojo Guerra Manuel A. , Roth Christina , Szécsényi-Nagy Anna , Wahl Joachim , Meyer Matthias , Krause Johannes , Brown Dorcas , Anthony David , Cooper Alan , Alt Kurt Werner , Reich David
Published: February 2015

We generated genome-wide data from 69 Europeans who lived between 8,000-3,000 years ago by enriching ancient DNA libraries for a target set of almost four hundred thousand polymorphisms. Enrichment of these positions decreases the sequencing required for genome-wide ancient DNA analysis by a median of around 250-fold, allowing us to study an order of magnitude more individuals than previous studies and to obtain new insights about the past. We show that the populations of western and far eastern Europe followed opposite trajectories between 8,000-5,000 years ago. At the beginning of the Neolithic period in Europe, ~8,000-7,000 years ago, closely related groups of early farmers appeared in Germany, Hungary, and Spain, different from indigenous hunter-gatherers, whereas Russia was inhabited by a distinctive population of hunter-gatherers with high affinity to a ~24,000 year old Siberian6. By ~6,000-5,000 years ago, a resurgence of hunter-gatherer ancestry had occurred throughout much of Europe, but in Russia, the Yamnaya steppe herders of this time were descended not only from the preceding eastern European hunter-gatherers, but from a population of Near Eastern ancestry. Western and Eastern Europe came into contact ~4,500 years ago, as the Late Neolithic Corded Ware people from Germany traced ~3/4 of their ancestry to the Yamnaya, documenting a massive migration into the heartland of Europe from its eastern periphery. This steppe ancestry persisted in all sampled central Europeans until at least ~3,000 years ago, and is ubiquitous in present-day Europeans. These results provide support for the theory of a steppe origin of at least some of the Indo-European languages of Europe.
Patterns of Metabolite Changes Identified from Large-Scale Gene Perturbations in Arabidopsis Using a Genome-Scale Metabolic Network
Authors: Kim Taehyong , Dreher Kate , Nilo-Poyanco Ricardo , Lee Insuk , Fiehn Oliver , Lange Bernd Markus , Nikolau Basil J. , Sumner Lloyd , Welti Ruth , Wurtele Eve S. , Rhee Seung Y.
Published: February 2015

Metabolomics enables quantitative evaluation of metabolic changes caused by genetic or environmental perturbations. However, little is known about how perturbing a single gene changes the metabolic system as a whole and which network and functional properties are involved in this response. To answer this question, we investigated the metabolite profiles from 136 mutants with single gene perturbations of functionally diverse Arabidopsis (Arabidopsis thaliana) genes. Fewer than 10 metabolites were changed significantly relative to the wild type in most of the mutants, indicating that the metabolic network was robust to perturbations of single metabolic genes. These changed metabolites were closer to each other in a genome-scale metabolic network than expected by chance, supporting the notion that the genetic perturbations changed the network more locally than globally. Surprisingly, the changed metabolites were close to the perturbed reactions in only 30% of the mutants of the well-characterized genes. To determine the factors that contributed to the distance between the observed metabolic changes and the perturbation site in the network, we examined nine network and functional properties of the perturbed genes. Only the isozyme number affected the distance between the perturbed reactions and changed metabolites. This study revealed patterns of metabolic changes from large-scale gene perturbations and relationships between characteristics of the perturbed genes and metabolic changes.
Relationship between non‐alcoholic fatty liver disease and MIA syndrome
Authors: Mikolasevic Ivana , Stimac Davor , Racki Sanjin , Zaputovic Luka , Devcic Bosiljka , Jelic Ita , Lukenda Vesna , Radic Mladen , Orlic Lidija
Published: February 2015

Non‐alcoholic fatty liver disease (NAFLD) is an important factor in the pathogenesis of cardiovascular diseases in the general population. Recently, it has been shown that NAFLD is highly prevalent in chronic kidney disease (CKD) patients. Ninety‐four hemodialysis (HD) patients were followed for a time period of 18 months or until death. Patient's survival rate was determined in relation to their nutritional and inflammatory state, and the presence of NAFLD. We also investigated the association between the presence of NAFLD and the patients' nutritional and inflammatory state. We did not find any significant association between the clinical parameters of nutritional status and the mortality rate. However, the mortality rate was statistically significantly higher in patients with low serum albumin and high high‐sensitive C‐reactive protein (hs‐CRP) levels and in those who had NAFLD. Surprisingly, patients who had received enteral nutrition did not have a better survival rate. The severity of liver steatosis was negatively correlated with the serum albumin levels, while it was positively correlated with hs‐CRP values. Furthermore, serum albumin levels showed a negative correlation with hs‐CRP levels. We did not find any significant association between the presence of NAFLD and clinical parameters of nutrition. We have shown that NAFLD could be one more possible example of reverse epidemiology in patients undergoing HD. NAFLD may be the missing link that causally ties malnutrition, inflammation, and atherosclerosis syndrome to the morbidity and mortality in patients undergoing HD.
Empirical Estimation of Stream Discharge Using Channel Geometry in Low‐Gradient, Sand‐Bed Streams of the Southeastern Plains
Authors: Sefick Stephen A. , Kalin Latif , Kosnicki Ely , Schneid Brad P. , Jarrell Miller S. , Anderson Chris J. , Paller Michael H. , Feminella Jack W.
Published: February 2015

Manning's equation is used widely to predict stream discharge (Q) from hydraulic variables when logistics constrain empirical measurements of in‐bank flow events. Uncertainty in Manning's roughness (nM) is the major source of error in natural channels, and sand‐bed streams pose difficulties because flow resistance is affected by flow‐dependent bed configuration. Our study was designed to develop and validate models for estimatingQfrom channel geometry easily derived from cross‐sectional surveys and availableGISdata. A database was compiled consisting of 484Qmeasurements from 75 sand‐bed streams in Alabama, Georgia, South Carolina, North Carolina (Southeastern Plains), and Florida (Southern Coastal Plain), with six New Zealand streams included to develop statistical models to predictQfrom hydraulic variables. Model error characteristics were estimated with leave‐one‐site‐out jackknifing. Independent data of 317Qmeasurements from 55 Southeastern Plains streams indicated the model (Q = AcRH0.6906S0.1216; whereAcis the channel area,RHis the hydraulic radius, andSis the bed slope) best predictedQ, based on Akaike's information criterion and root mean square error. Models also were developed from smallerQrange subsets to explore if subsets increased predictive ability, but error fit statistics suggested that these were not reasonable alternatives to the above equation. Thus, we recommend the above equation for predicting in‐bankQof unbraided, sandy streams of the Southeastern Plains.
The Visceromotor and Somatic Afferent Nerves of the Penis
Authors: Diallo Djibril , Zaitouna Mazen , Alsaid Bayan , Quillard Jeanine , Ba Nathalie , Allodji Rodrigue Sètchéou , Benoit Gérard , Bedretdinova Dina , Bessede Thomas
Published: February 2015

Introduction

Innervation of the penis supports erectile and sensory functions.

Aim

This article aims to study the efferent autonomic (visceromotor) and afferent somatic (sensory) nervous systems of the penis and to investigate how these systems relate to vascular pathways.

Methods

Penises obtained from five adult cadavers were studied via computer-assisted anatomic dissection (CAAD).

Main Outcome Measures

The number of autonomic and somatic nerve fibers was compared using the Kruskal–Wallis test.

Results

Proximally, penile innervation was mainly somatic in the extra-albugineal sector and mainly autonomic in the intracavernosal sector. Distally, both sectors were almost exclusively supplied by somatic nerve fibers, except the intrapenile vascular anastomoses that accompanied both somatic and autonomic (nitrergic) fibers. From this point, the neural immunolabeling within perivascular nerve fibers was mixed (somatic labeling and autonomic labeling). Accessory afferent, extra-albugineal pathways supplied the outer layers of the penis.

Conclusions

There is a major change in the functional type of innervation between the proximal and distal parts of the intracavernosal sector of the penis. In addition to the pelvis and the hilum of the penis, the intrapenile neurovascular routes are the third level where the efferent autonomic (visceromotor) and the afferent somatic (sensory) penile nerve fibers are close. Intrapenile neurovascular pathways define a proximal penile segment, which guarantees erectile rigidity, and a sensory distal segment.
Time-Optimal Trajectory Planning of Cable-Driven Parallel Mechanisms for Fully Specified Paths With G1-Discontinuities
Authors: Barnett Eric , Gosselin Clément
Published: February 2015

Time-optimal trajectory planning (TOTP) is a well-studied problem in robotics and manufacturing, which involves the minimization of the time required for the operation point of a mechanism to follow a path, subject to a set of constraints. A TOTP technique, designed for fully specified paths that include abrupt changes in direction, was previously introduced by the first author of this paper: an incremental approach called minimum-time trajectory shaping (MTTS) was used. In the current paper, MTTS is converted to a dynamic technique and adapted for use with cable-driven parallel robots, which exhibit cable tension and motor torque constraints. For many applications, cable tensions along a path are verified after trajectory generation, rather than imposed during trajectory generation. For the technique proposed in this paper, the cable-tension constraints are imposed directly and fully integrated with MTTS, during trajectory generation, thus maintaining a time-optimal solution. MTTS is applied to a test system and path, and compared to the bang–bang technique. With the same constraints, the results obtained with both techniques are found to be very close. However, MTTS can be applied to a wider variety of paths, and accepts constraints on jerk and total acceleration that would be difficult to apply using the bang–bang approach.
Analysis of Heat Conduction in a Heterogeneous Material by a Multiple-Scale Averaging Method
Authors: White James
Published: February 2015

In order to better manage computational requirements in the study of thermal conduction with short-scale heterogeneous materials, one is motivated to arrange the thermal energy equation into an accurate and efficient form with averaged properties. This should then allow an averaged temperature solution to be determined with a moderate computational effort. That is the topic of this paper as it describes the development using multiple-scale analysis of an averaged thermal energy equation based on Fourier heat conduction for a heterogeneous material with isotropic properties. The averaged energy equation to be reported is appropriate for a stationary or moving solid and three-dimensional heat flow. Restrictions are that the solid must display its heterogeneous properties over short spatial and time scales that allow averages of its properties to be determined. One distinction of the approach taken is that all short-scale effects, both moving and stationary, are combined into a single function during the analytical development. The result is a self-contained form of the averaged energy equation. By eliminating the need for coupling the averaged energy equation with external local problem solutions, numerical solutions are simplified and made more efficient. Also, as a result of the approach taken, nine effective averaged thermal conductivity terms are identified for three-dimensional conduction (and four effective terms for two-dimensional conduction). These conductivity terms are defined with two types of averaging for the component material conductivities over the short-scales and in terms of the relative proportions of the short-scales. Numerical results are included and discussed.
Heat Conduction in Nanostructured Materials Predicted by Phonon Bulk Mean Free Path Distribution
Authors: Romano Giuseppe , Grossman Jeffrey C.
Published: February 2015

We develop a computational framework, based on the Boltzmann transport equation (BTE), with the ability to compute thermal transport in nanostructured materials of any geometry using, as the only input, the bulk cumulative thermal conductivity. The main advantage of our method is twofold. First, while the scattering times and dispersion curves are unknown for most materials, the phonon mean free path (MFP) distribution can be directly obtained by experiments. As a consequence, a wider range of materials can be simulated than with the frequency-dependent (FD) approach. Second, when the MFP distribution is available from theoretical models, our approach allows one to include easily the material dispersion in the calculations without discretizing the phonon frequencies for all polarizations thereby reducing considerably computational effort. Furthermore, after deriving the ballistic and diffusive limits of our model, we develop a multiscale method that couples phonon transport across different scales, enabling efficient simulations of materials with wide phonon MFP distributions length. After validating our model against the FD approach, we apply the method to porous silicon membranes and find good agreement with experiments on mesoscale pores. By enabling the investigation of thermal transport in unexplored nanostructured materials, our method has the potential to advance high-efficiency thermoelectric devices.
An Investigation on Sensitivity of Ignition Delay and Activation Energy in Diesel Combustion
Authors: Joshi Umashankar , Zheng Ziliang , Shrestha Amit , Henein Naeim , Sattler Eric
Published: February 2015

The auto-ignition process plays a major role in the combustion, performance, fuel economy, and emission in diesel engines. The auto-ignition quality of different fuels has been rated by its cetane number (CN) determined in the cooperative fuel research engine, according to ASTM D613. More recently, the ignition quality tester (IQT), a constant volume vessel, has been used to determine the derived cetane number (DCN) to avoid the elaborate, time consuming, and costly engine tests, according to ASTM D6890. The ignition delay (ID) period in these two standard tests and many investigations has been considered to be the time period between start of injection (SOI) and start of combustion (SOC). The ID values determined in different investigations can vary due to differences in instrumentation and definitions. This paper examines the different definitions and the parameters that effect ID period. In addition, the activation energy dependence on the ID definition is investigated. Furthermore, results of an experimental investigation in a single-cylinder research diesel engine will be presented, while the charge density is kept constant during the ID period. The global activation energy is determined and its sensitivity to the charge temperature is examined.
Multiattribute probabilistic prostate elastic registration (MAPPER): Application to fusion of ultrasound and magnetic resonance imaging
Authors: Sparks Rachel , Nicolas Bloch B. , Feleppa Ernest , Barratt Dean , Moses Daniel , Ponsky Lee , Madabhushi Anant
Published: February 2015

Purpose:

Transrectal ultrasound (TRUS)‐guided needle biopsy is the current gold standard for prostate cancer diagnosis. However, up to 40% of prostate cancer lesions appears isoechoic on TRUS. Hence, TRUS‐guided biopsy has a high false negative rate for prostate cancer diagnosis. Magnetic resonance imaging (MRI) is better able to distinguish prostate cancer from benign tissue. However, MRI‐guided biopsy requires special equipment and training and a longer procedure time. MRI‐TRUS fusion, where MRI is acquired preoperatively and then aligned to TRUS, allows for advantages of both modalities to be leveraged during biopsy. MRI‐TRUS‐guided biopsy increases the yield of cancer positive biopsies. In this work, the authors present multiattribute probabilistic postate elastic registration (MAPPER) to align prostate MRI and TRUS imagery.

Methods:

MAPPER involves (1) segmenting the prostate on MRI, (2) calculating a multiattribute probabilistic map of prostate location on TRUS, and (3) maximizing overlap between the prostate segmentation on MRI and the multiattribute probabilistic map on TRUS, thereby driving registration of MRI onto TRUS. MAPPER represents a significant advancement over the current state‐of‐the‐art as it requires no user interaction during the biopsy procedure by leveraging texture and spatial information to determine the prostate location on TRUS. Although MAPPER requires manual interaction to segment the prostate on MRI, this step is performed prior to biopsy and will not substantially increase biopsy procedure time.

Results:

MAPPER was evaluated on 13 patient studies from two independent datasets—Dataset 1 has 6 studies acquired with a side‐firing TRUS probe and a 1.5 T pelvic phased‐array coil MRI; Dataset 2 has 7 studies acquired with a volumetric end‐firing TRUS probe and a 3.0 T endorectal coil MRI. MAPPER has a root‐mean‐square error (RMSE) for expert selected fiducials of 3.36 ± 1.10 mm for Dataset 1 and 3.14 ± 0.75 mm for Dataset 2. State‐of‐the‐art MRI‐TRUS fusion methods report RMSE of 3.06–2.07 mm.

Conclusions:

MAPPER aligns MRI and TRUS imagery without manual intervention ensuring efficient, reproducible registration. MAPPER has a similar RMSE to state‐of‐the‐art methods that require manual intervention.
Speed and Heart-Rate Profiles in Skating and Classical Cross-Country-Skiing Competitions
Authors: Bolger Conor M. , Kocbach Jan , Hegge Ann Magdalen , Sandbakk Øyvind
Published: February 2015

Purpose:

To compare the speed and heart-rate profiles during international skating and classical competitions in male and female world-class cross-country skiers.

Methods:

Four male and 5 female skiers performed individual time trials of 15 km (men) and 10 km (women) in the skating and classical techniques on 2 consecutive days. Races were performed on the same 5-km course. The course was mapped with GPS and a barometer to provide a valid course and elevation profile. Time, speed, and heart rate were determined for uphill, flat, and downhill terrains throughout the entire competition by wearing a GPS and a heart-rate monitor.

Results:

Times in uphill, flat, and downhill terrain were ~55%, 15–20%, and 25–30%, respectively, of the total race time for both techniques and genders. The average speed differences between skating and classical skiing were 9% and 11% for men and women, respectively, and these values were 12% and 15% for uphill, 8% and 13% for flat (all P < .05), and 2% and 1% for downhill terrain. The average speeds for men were 9% and 11% faster than for women in skating and classical, respectively, with corresponding numbers of 11% and 14% for uphill, 6% and 11% for flat, and 4% and 5% for downhill terrain (all P < .05). Heart-rate profiles were relatively independent of technique and gender.

Conclusions:

The greatest performance differences between the skating and classical techniques and between the 2 genders were found on uphill terrain. Therefore, these speed differences could not be explained by variations in exercise intensity.
Factors Influencing Physical and Technical Variability in the English Premier League
Authors: Bush Michael D. , Archer David T. , Hogg Robert , Bradley Paul S.
Published: February 2015

Purpose:

To investigate match-to-match variability of physical and technical performances in English Premier League players and quantify the influence of positional and contextual factors.

Methods:

Match data (N = 451) were collected using a multicamera computerized tracking system across multiple seasons (2005–06 to 2012–13). The coefficient of variation (CV) was calculated from match to match for physical and technical performances in selected positions across different match contexts (location, standard, and result).

Results:

Wide midfielders demonstrated the greatest CVs for total distance (4.9% ± 5.9%) and central midfielders the smallest (3.6% ± 2.0%); nevertheless, all positions exhibited CVs <5% (P > .05, effect size [ES] 0.1–0.3). Central defenders demonstrated the greatest CVs and wide midfielders the lowest for both high-intensity running (20.2% ± 8.8% and 13.7% ± 7.7%, P < .05, ES 0.4–0.8) and sprint distance (32.3% ± 13.8% and 22.6% ± 11.2%, P < .05, ES 0.5–0.8). Technical indicators such as tackles (83.7% ± 42.3%), possessions won (47.2% ± 27.9%), and interceptions (59.1% ± 37.3%) illustrated substantial variability for attackers compared with all other positions (P < .05, ES 0.4–1.1). Central defenders demonstrated large variability for the number of times tackled per match (144.9% ± 58.3%) and passes attempted and received compared with other positions (39.2% ± 17.5% and 46.9% ± 20.2%, P < .001, ES 0.6–1.8). Contextual factors had limited impact on the variability of physical and technical parameters.

Conclusions:

The data demonstrate that technical parameters varied more from match to match than physical parameters. Defensive players (fullbacks and central defenders) displayed higher CVs for offensive technical variables, while attacking players (attackers and wide midfielders) exhibited higher CVs for defensive technical variables. Physical and technical performances are variable per se regardless of context.