bluuebunny/crossref_metadata_2025 huggingface dataset:
Fatigue Determination of Photo chromic Dyes in Silica and Polyamide Matrices via Analysis of CIELAB Parameters
Authors: Durasevic Vedran , Parac-Osterman Durdica
Published: July 2014

To address reported problems in investigating photochromic dye fatigue, this paper describes a new method of “dissolved” photochromic organic dye analysis within polar silica matrices. Conditions under which a photochromic response occurs in a given material are defined by specifying the light source (irradiation wavelength) and exposure time that leads to photochromism. Fatigue, defined as poor lightfastness, is researched through consecutive cycles of exposure to the direct influence of a defined UV irradiation source. From the spectrophotometric graphic analysis in CIELAB, a conclusion can be made on the lifespan of photochromic textile products. This paper addresses issues regarding the rate of color development, and the controlled, predictable return to a colorless state, which is the base of any device working on the principle of reversibility.
Relación entre el tiempo de uso de las redes sociales en internet y la salud mental en adolescentes colombianos.
Authors: Rodríguez Puentes Adriana Paola , Fernández Parra Antonio
Published: July 2014

El objetivo de esta investigación es determinar si hay diferencias entre grupos de adolescentes de grado 7° de la ciudad de Bogotá, con diferentes tiempos de uso de las redes sociales en problemáticas de tipo internalizante, externalizante, la soledad percibida, el funcionamiento familiar y el sexo. El estudio con diseño ex post facto valoró el efecto del tiempo de uso de redes sociales a tres niveles (bajo, medio y alto) a través de un cuestionario socio demográfico diseñado para tal fin: el LSRQ, el FACES III, CDI y el YSR. Participaron 96 estudiantes con un rango de edades entre los 11 y 15 años. Se encontró que entre los participantes con un elevado tiempo de uso de las redes sociales, eran mayores los problemas de tipo externalizante (conducta agresiva, ruptura de reglas y problemas de atención). Se discute la necesidad de que en futuras investigaciones se enfaticen los factores positivos que para el desarrollo de los adolescentes puede tener el uso de las redes sociales a través de Internet.
Análisis del tipo de interacciones que ocurren entre investigadores durante la presentación de trabajos académicos.
Authors: Padilla Vargas Maria Antonia
Published: July 2014

Aunque se considera que el desarrollo científico y el progreso intelectual se producen a través del intercambio de ideas provocadas por la interacción entre los científicos, el tipo de interacciones que tienen lugar entre los investigadores de las mismas instituciones cuando uno de ellos presenta su trabajo a los colegas no se ha estudiado sistemáticamente. Dado lo anterior, se llevó a cabo un estudio preliminar cuyo objetivo fue analizar el tipo de interacciones que ocurrían entre investigadores miembros de una misma institución que trabajaban en proyectos distintos, cuando alguno de ellos presentaba un trabajo al resto de sus colegas. Se identificó el número de intervenciones hechas, el estatus académico de quién intervenía, los aspectos sobre los cuales versaba la intervención y el resultado de dicha intervención (acuerdo o no). Participaron ocho investigadores titulares, cinco asociados, 16 estudiantes de posgrado y cuatro becarios. Se grabaron, transcribieron y analizaron las interacciones ocurridas durante 13 presentaciones de trabajos. Los resultados mostraron que: a) a menor estatus académico del ponente, mayor fue el número de intervenciones; b) los que más intervinieron fueron los que tenían mayor estatus académico; c) las intervenciones fueron tanto teóricas como metodológicas, con una ligera ventaja de las primeras sobre las segundas, y d) a mayor diferencia de estatus entre el ponente y el que intervenía, mayor fue el número de acuerdos. Se discute cómo el estatus modula las interacciones de los grupos científicos, así como las relaciones de dominación que se presentan en el ámbito de la ciencia.
Riesgo sexual en adolescentes según la edad de debut sexual.
Authors: Espada José P. , Morales Alexandra , Orgilés Mireia
Published: July 2014

En España los jóvenes debutan sexualmente antes que en otros países; sin embargo, poco se sabe de la relación entre la edad de debut sexual y el comportamiento sexual en esta población. Se analizan las prácticas sexuales y el uso del preservativo según la edad de debut sexual en adolescentes españoles sexualmente experimentados (N = 351); la edad media fue 15.9 años (DT = .75, rango: 14-18). Se establecieron tres grupos a partir de la edad de debut sexual informada: debut sexual temprano (anterior a los 15 años), promedio (15 años) y tardío (posterior a los 15 años). El grupo con debut sexual temprano practicó en mayor medida masturbación mutua, coito vaginal y sexo oral, con un número de parejas sexuales superior al resto. El uso del preservativo en la primera relación sexual, el porcentaje de uso y el uso consistente del preservativo fue inferior en el grupo debut sexual temprano respecto a los otros dos. El debut sexual anterior a los 15 años se asoció con mayor riesgo de contraer infecciones sexuales por déficit en el uso del preservativo y mayor exposición sexual. Los hallazgos de este estudio sugieren que la edad de debut sexual tiene implicaciones en la salud sexual de los jóvenes.
Numerical and Experimental Investigation of the Effect of Geometrical Parameters on the Performance of a Contraction-Expansion Helical Mixer
Authors: Dong Liang , Shufen Zhang
Published: July 2014

In this study, the mixing efficiency of a passive contraction-expansion helical mixer, which combines several features, such as helical pipes for induction of secondary flows and sudden expansion and contraction array for expansion vortices, was numerically and experimentally studied. We employed the method of Box–Behnken to select the appropriate design points. Then, various configurations were investigated via computational fluid dynamics (CFD) simulations. The extent of mixing was evaluated by monitoring the residence time distribution (RTD) and observing the shape of the RTD curves. A fast competitive-consecutive diazo coupling reaction is carried out to validate the RTD results. The influences of radius of curvature of the helical mixer, ratio of the length of the contraction part to expansion part, pitch of helical mixer, and the Reynolds number (Re) on mixing efficiency, and pressure drop were also investigated. As expected, the radius of curvature of the helical mixer, ratio of the length of the contraction part to expansion part, and the Reynolds number affected significantly the mixing efficiency, while the pitch of helical mixer had little influence on mixing efficiency. Quadratic models for mixing efficiency and pressure drop were then proposed and could be used for designing the optimal contraction-expansion helical mixer for the required pumping power.
Recurrent pancreatitis in a patient with familial hypocalciuric hypercalcaemia treated successfully with cinacalcet
Authors: Gunganah Kirun , Grossman Ashley , Druce Maralyn
Published: July 2014

A 22-year-old female student presented with a history of recurrent pancreatitis. The commonest causes of pancreatitis, including drugs, gallstones, corticosteroids, excess alcohol and hypertriglyceridaemia, were excluded. She was found to have an elevated serum calcium level that was considered to be the cause of her pancreatitis, with a detectable serum parathyroid hormone (PTH). An initial diagnosis of primary hyperparathyroidism was made. However, two neck explorations failed to reveal a parathyroid adenoma. She was referred to our unit three years later as her episodes of pancreatitis were becoming more frequent and her calcium level remained persistently elevated. Her investigations were as follows: elevated adjusted calcium level of 2.79 mmol/l (2.2–2.58), PTH level of 4.2 pmol/l (0.6–6.0), low 24 h urine calcium of 0.3 mmol/l and a urine calcium:creatinine ratio of <0.003. A clinical diagnosis of familial hypocalciuric hypercalcaemia (FHH) was made and confirmed on genetic testing that showed a c.1703 G>A mutation in the calcium-sensing receptor gene. Although the hypercalcaemia of FHH is usually without sequelae due to the generalised changes in calcium sensing, in the presence of this complication she was started on cinacalcet 30 mg daily. She had one further episode of pancreatitis with calcium levels ranging between 2.53 and 2.66 mmol/l. Her cinacalcet was gradually increased to 30 mg three times daily, maintaining her calcium levels in the range of 2.15–2.20 mmol/l. She has not had a further episode of pancreatitis for more than 2 years.

FHH is usually a benign condition with minimal complications from hypercalcaemia. Pancreatitis has been reported rarely, and no clear management strategy has been defined in these cases. Cinacalcet was successfully used in treating recurrent pancreatitis in a patient with FHH by maintaining calcium levels in the lower part of the reference range. Whether or not this is an effective long-term treatment remains yet to be seen.

Learning points

FHH is an important differential diagnosis for hypercalcaemia.

FHH can rarely cause pancreatitis.

No clear strategy is available to help in the management of patients with pancreatitis due to FHH.

Cinacalcet was effective in lowering serum calcium levels and reducing the frequency of pancreatitis in our patient with FHH.
Consistent and Heritable Alterations of DNA Methylation Are Induced by Tissue Culture in Maize
Authors: Stelpflug Scott C , Eichten Steven R , Hermanson Peter J , Springer Nathan M , Kaeppler Shawn M
Published: July 2014

Plants regenerated from tissue culture and their progenies are expected to be identical clones, but often display heritable molecular and phenotypic variation. We characterized DNA methylation patterns in callus, primary regenerants, and regenerant-derived progenies of maize using immunoprecipitation of methylated DNA (meDIP) to assess the genome-wide frequency, pattern, and heritability of DNA methylation changes. Although genome-wide DNA methylation levels remained similar following tissue culture, numerous regions exhibited altered DNA methylation levels. Hypomethylation events were observed more frequently than hypermethylation following tissue culture. Many of the hypomethylation events occur at the same genomic sites across independent regenerants and cell lines. The DNA methylation changes were often heritable in progenies produced from self-pollination of primary regenerants. Methylation changes were enriched in regions upstream of genes and loss of DNA methylation at promoters was associated with altered expression at a subset of loci. Differentially methylated regions (DMRs) found in tissue culture regenerants overlap with the position of naturally occurring DMRs more often than expected by chance with 8% of tissue culture hypomethylated DMRs overlapping with DMRs identified by profiling natural variation, consistent with the hypotheses that genomic stresses similar to those causing somaclonal variation may also occur in nature, and that certain loci are particularly susceptible to epigenetic change in response to these stresses. The consistency of methylation changes across regenerants from independent cultures suggests a mechanistic response to the culture environment as opposed to an overall loss of fidelity in the maintenance of epigenetic states.
Unit of Measurement Used and Parent Medication Dosing Errors
Authors: Yin H. Shonna , Dreyer Benard P. , Ugboaja Donna C. , Sanchez Dayana C. , Paul Ian M. , Moreira Hannah A. , Rodriguez Luis , Mendelsohn Alan L.
Published: July 2014

BACKGROUND AND OBJECTIVES:

Adopting the milliliter as the preferred unit of measurement has been suggested as a strategy to improve the clarity of medication instructions; teaspoon and tablespoon units may inadvertently endorse nonstandard kitchen spoon use. We examined the association between unit used and parent medication errors and whether nonstandard instruments mediate this relationship.

METHODS:

Cross-sectional analysis of baseline data from a larger study of provider communication and medication errors. English- or Spanish-speaking parents (n = 287) whose children were prescribed liquid medications in 2 emergency departments were enrolled. Medication error defined as: error in knowledge of prescribed dose, error in observed dose measurement (compared to intended or prescribed dose); >20% deviation threshold for error. Multiple logistic regression performed adjusting for parent age, language, country, race/ethnicity, socioeconomic status, education, health literacy (Short Test of Functional Health Literacy in Adults); child age, chronic disease; site.

RESULTS:

Medication errors were common: 39.4% of parents made an error in measurement of the intended dose, 41.1% made an error in the prescribed dose. Furthermore, 16.7% used a nonstandard instrument. Compared with parents who used milliliter-only, parents who used teaspoon or tablespoon units had twice the odds of making an error with the intended (42.5% vs 27.6%, P = .02; adjusted odds ratio=2.3; 95% confidence interval, 1.2–4.4) and prescribed (45.1% vs 31.4%, P = .04; adjusted odds ratio=1.9; 95% confidence interval, 1.03–3.5) dose; associations greater for parents with low health literacy and non–English speakers. Nonstandard instrument use partially mediated teaspoon and tablespoon–associated measurement errors.

CONCLUSIONS:

Findings support a milliliter-only standard to reduce medication errors.
Sleep Environment Risks for Younger and Older Infants
Authors: Colvin Jeffrey D. , Collie-Akers Vicki , Schunn Christy , Moon Rachel Y.
Published: July 2014

OBJECTIVE:

Sudden infant death syndrome and other sleep-related causes of infant mortality have several known risk factors. Less is known about the association of those risk factors at different times during infancy. Our objective was to determine any associations between risk factors for sleep-related deaths at different ages.

METHODS:

A cross-sectional study of sleep-related infant deaths from 24 states during 2004–2012 contained in the National Center for the Review and Prevention of Child Deaths Case Reporting System, a database of death reports from state child death review teams. The main exposure was age, divided into younger (0–3 months) and older (4 months to 364 days) infants. The primary outcomes were bed-sharing, objects in the sleep environment, location (eg, adult bed), and position (eg, prone).

RESULTS:

A total of 8207 deaths were analyzed. Younger victims were more likely bed-sharing (73.8% vs 58.9%, P < .001) and sleeping in an adult bed/on a person (51.6% vs 43.8%, P < .001). A higher percentage of older victims had an object in the sleep environment (39.4% vs 33.5%, P < .001) and changed position from side/back to prone (18.4% vs 13.8%, P < .001). Multivariable regression confirmed these associations.

CONCLUSIONS:

Risk factors for sleep-related infant deaths may be different for different age groups. The predominant risk factor for younger infants is bed-sharing, whereas rolling into objects in the sleep area is the predominant risk factor for older infants. Parents should be warned about the dangers of these specific risk factors appropriate to their infant’s age.
Modeling chemical compositions of municipal solid waste
Authors: Chakma Sumedha , Vaishya Rakesh Chandra , Yadav Alok Kumar
Published: July 2014

The objective of the paper is to develop a mathematical model to compute the chemical compositions of the organic portion of municipal solid waste (MSW) using proximate analysis data. The validation of the developed models were done using test of hypothesis and field samples. In the study, MSW samples were collected from 23 different locations throughout the year and chemical compositions of the organic matter were determined such as carbon, hydrogen, oxygen, nitrogen and sulfur using elemental analyser. Proximate analysis such as combustible volatile matter (VM) and ash content were also measured for all the sites. The range of variation in the chemical compositions and proximate analysis were observed as 5·2% ≤ carbon ≤ 21·2%, 0·64% ≤ hydrogen ≤ 2·7%, 17·2% ≤ oxygen ≤ 67·6%, 0·3% ≤ nitrogen ≤ 1·1%, 0·1% ≤ sulfur ≤ 0·37%, 9·3% ≤ VM ≤ 35·5%, 18·6% ≤ ash ≤ 72·1% on dry basis. Various statistical analyses such as standard deviation, mean, P value and F value were also carried out in the study.
From Seed to Tree: Developing Community Support for Perinatally Bereaved Mothers
Authors: Wright Patricia Moyle , Shea Diane M. , Gallagher Robin
Published: July 2014

Despite burgeoning evidence on the positive effects of perinatal loss support groups, some communities still lack such services. Those wishing to begin a support group may find the task daunting, especially if there is little support for their efforts. In this article, the authors discuss the development of a pregnancy loss support group, which included a community assessment, launching a pilot program, and providing training for facilitators. Other practical considerations will also be reviewed, such as finding a location for the group and securing funding for advertising.
The role of logical interpretations in program development
Authors: Martins Manuel A. , Madeira Alexandre , Barbosa Luis S.
Published: July 2014

Stepwise refinement of algebraic specifications is a well known formal
methodology for program development. However, traditional notions of refinement
based on signature morphisms are often too rigid to capture a number of
relevant transformations in the context of software design, reuse, and
adaptation. This paper proposes a new approach to refinement in which signature
morphisms are replaced by logical interpretations as a means to witness
refinements. The approach is first presented in the context of equational
logic, and later generalised to deductive systems of arbitrary dimension. This
allows, for example, refining sentential into equational specifications and the
latter into modal ones.
Universal First-Order Logic is Superfluous for NL, P, NP and coNP
Authors: Borges Nerio , Bonet Blai
Published: July 2014

In this work we continue the syntactic study of completeness that began with
the works of Immerman and Medina. In particular, we take a conjecture raised by
Medina in his dissertation that says if a conjunction of a second-order and a
first-order sentences defines an NP-complete problems via fops, then it must be
the case that the second-order conjoint alone also defines a NP-complete
problem. Although this claim looks very plausible and intuitive, currently we
cannot provide a definite answer for it. However, we can solve in the
affirmative a weaker claim that says that all ``consistent'' universal
first-order sentences can be safely eliminated without the fear of losing
completeness. Our methods are quite general and can be applied to complexity
classes other than NP (in this paper: to NLSPACE, PTIME, and coNP), provided
the class has a complete problem satisfying a certain combinatorial property.
Revisiting Trace and Testing Equivalences for Nondeterministic and Probabilistic Processes
Authors: Bernardo Marco , De Nicola Rocco , Loreti Michele
Published: July 2014

Two of the most studied extensions of trace and testing equivalences to
nondeterministic and probabilistic processes induce distinctions that have been
questioned and lack properties that are desirable. Probabilistic
trace-distribution equivalence differentiates systems that can perform the same
set of traces with the same probabilities, and is not a congruence for parallel
composition. Probabilistic testing equivalence, which relies only on extremal
success probabilities, is backward compatible with testing equivalences for
restricted classes of processes, such as fully nondeterministic processes or
generative/reactive probabilistic processes, only if specific sets of tests are
admitted. In this paper, new versions of probabilistic trace and testing
equivalences are presented for the general class of nondeterministic and
probabilistic processes. The new trace equivalence is coarser because it
compares execution probabilities of single traces instead of entire trace
distributions, and turns out to be compositional. The new testing equivalence
requires matching all resolutions of nondeterminism on the basis of their
success probabilities, rather than comparing only extremal success
probabilities, and considers success probabilities in a trace-by-trace fashion,
rather than cumulatively on entire resolutions. It is fully backward compatible
with testing equivalences for restricted classes of processes; as a
consequence, the trace-by-trace approach uniformly captures the standard
probabilistic testing equivalences for generative and reactive probabilistic
processes. The paper discusses in full details the new equivalences and
provides a simple spectrum that relates them with existing ones in the setting
of nondeterministic and probabilistic processes.
Monadic second-order definable graph orderings
Authors: Blumensath Achim , Courcelle Bruno
Published: July 2014

We study the question of whether, for a given class of finite graphs, one can
define, for each graph of the class, a linear ordering in monadic second-order
logic, possibly with the help of monadic parameters. We consider two variants
of monadic second-order logic: one where we can only quantify over sets of
vertices and one where we can also quantify over sets of edges. For several
special cases, we present combinatorial characterisations of when such a linear
ordering is definable. In some cases, for instance for graph classes that omit
a fixed graph as a minor, the presented conditions are necessary and
sufficient; in other cases, they are only necessary. Other graph classes we
consider include complete bipartite graphs, split graphs, chordal graphs, and
cographs. We prove that orderability is decidable for the so called
HR-equational classes of graphs, which are described by equation systems and
generalize the context-free languages.
Unification modulo a 2-sorted Equational theory for Cipher-Decipher Block Chaining
Authors: Anantharaman Siva , Bouchard Christopher , Narendran Paliath , Rusinowitch Michaël
Published: July 2014

We investigate unification problems related to the Cipher Block Chaining
(CBC) mode of encryption. We first model chaining in terms of a simple,
convergent, rewrite system over a signature with two disjoint sorts: list and
element. By interpreting a particular symbol of this signature suitably, the
rewrite system can model several practical situations of interest. An inference
procedure is presented for deciding the unification problem modulo this rewrite
system. The procedure is modular in the following sense: any given problem is
handled by a system of `list-inferences', and the set of equations thus derived
between the element-terms of the problem is then handed over to any
(`black-box') procedure which is complete for solving these element-equations.
An example of application of this unification procedure is given, as attack
detection on a Needham-Schroeder like protocol, employing the CBC encryption
mode based on the associative-commutative (AC) operator XOR. The 2-sorted
convergent rewrite system is then extended into one that fully captures a block
chaining encryption-decryption mode at an abstract level, using no AC-symbols;
and unification modulo this extended system is also shown to be decidable.
Ordered Models of the Lambda Calculus
Authors: Salibra Antonino , Carraro Alberto
Published: July 2014

Answering a question by Honsell and Plotkin, we show that there are two
equations between lambda terms, the so-called subtractive equations, consistent
with lambda calculus but not simultaneously satisfied in any partially ordered
model with bottom element. We also relate the subtractive equations to the open
problem of the order-incompleteness of lambda calculus, by studying the
connection between the notion of absolute unorderability in a specific point
and a weaker notion of subtractivity (namely n-subtractivity) for partially
ordered algebras. Finally we study the relation between n-subtractivity and
relativized separation conditions in topological algebras, obtaining an
incompleteness theorem for a general topological semantics of lambda calculus.
Herbrand-Confluence
Authors: Hetzl Stefan , Straßburger Lutz
Published: July 2014

We consider cut-elimination in the sequent calculus for classical first-order
logic. It is well known that this system, in its most general form, is neither
confluent nor strongly normalizing. In this work we take a coarser (and
mathematically more realistic) look at cut-free proofs. We analyze which
witnesses they choose for which quantifiers, or in other words: we only
consider the Herbrand-disjunction of a cut-free proof. Our main theorem is a
confluence result for a natural class of proofs: all (possibly infinitely many)
normal forms of the non-erasing reduction lead to the same
Herbrand-disjunction.
Strong Turing Degrees for Additive BSS RAM's
Authors: Gaßner Christine
Published: July 2014

For the additive real BSS machines using only constants 0 and 1 and order
tests we consider the corresponding Turing reducibility and characterize some
semi-decidable decision problems over the reals. In order to refine,
step-by-step, a linear hierarchy of Turing degrees with respect to this model,
we define several halting problems for classes of additive machines with
different abilities and construct further suitable decision problems. In the
construction we use methods of the classical recursion theory as well as
techniques for proving bounds resulting from algebraic properties. In this way
we extend a known hierarchy of problems below the halting problem for the
additive machines using only equality tests and we present a further
subhierarchy of semi-decidable problems between the halting problems for the
additive machines using only equality tests and using order tests,
respectively.
Undecidable First-Order Theories of Affine Geometries
Authors: Kuusisto Antti , Meyers Jeremy , Virtema Jonni
Published: July 2014

Tarski initiated a logic-based approach to formal geometry that studies
first-order structures with a ternary betweenness relation \beta, and a
quaternary equidistance relation \equiv. Tarski established, inter alia, that
the first-order (FO) theory of (R^2,\beta,\equiv) is decidable. Aiello and van
Benthem (2002) conjectured that the FO-theory of expansions of (R^2,\beta) with
unary predicates is decidable. We refute this conjecture by showing that for
all n>1, the FO-theory of the class of expansions of (R^2,\beta) with just one
unary predicate is not even arithmetical. We also define a natural and
comprehensive class C of geometric structures (T,\beta), and show that for each
structure (T,\beta) in C, the FO-theory of the class of expansions of (T,\beta)
with a single unary predicate is undecidable. We then consider classes of
expansions of structures (T,\beta) with a restricted unary predicate, for
example a finite predicate, and establish a variety of related undecidability
results. In addition to decidability questions, we briefly study the
expressivities of universal MSO and weak universal MSO over expansions of
(R^n,\beta). While the logics are incomparable in general, over expansions of
(R^n,\beta), formulae of weak universal MSO translate into equivalent formulae
of universal MSO.
Participation in Sports Teams and Suicidal Behavior: An Analysis of the 1995 National College Health Risk Behavior Survey
Authors: Lester David
Published: July 2014

A 1995 data set from a survey of college students carried out by the Centers for Disease Control was examined to explore whether participation in sports was associated with recent suicidal behavior. Overall, participation in college sports was associated with a reduced incidence of suicidal ideation in the past year, but had no association with attempted suicide in the past year. However, this protective effect was found for European American students, Hispanic Americans, and Asian Americans, but not for African Americans, and was stronger for male students than for female students.
Noise Distraction and Mental Practice in Closed and Open Motor Skills
Authors: Jeon Hyunjeong , Kim Jingu , Ali Asif , Choi Sungmok
Published: July 2014

Two experiments were conducted to investigate whether mental practice can serve as an effective intervention strategy for decreasing interference effects of distracting noise at the time of executing open (badminton service return) and closed (badminton serve) skills. In Experiment 1, 44 male students participated and in Experiment 2, 36 students participated. In both experiments, students were randomly assigned to one of three groups: (a) mental practice, (b) mental practice plus noise distraction (MPD), and (c) control. All participants performed 40 trials in the acquisition phase and 20 trials in the retention phase. Absolute error and adjusted variable error were recorded to measure performance. Experiment 1 showed that for a closed skill, the MPD group served with greater accuracy than did the control group in both acquisition and retention phases. Experiment 2 showed that for the open skill, the MP group performed with less error than did the control group, but only in the acquisition trials. Results indicate that mental practice may function to block out noise disturbances and that mental practice may work differently with different skill sets.
Observation of Omni Scale of Perceived Exertion during Fire Suppression Training
Authors: Goss Fredric L. , Robertson Robert J. , Deldin Anthony , Gibbs Bethany Barone , Hostler David
Published: July 2014

Ratings of perceived exertion in 66 firefighters before, during, and immediately after performing 20min. of fire suppression training were self-reported by the participants using the OMNI Walk-Run Scale and also recorded by a trained observer. The observer used the same definition of perceived exertion, instructions, and high and low anchoring procedures as the participants. Self-reported and observed ratings of perceived exertion did not differ before or during fire suppression training. Significant differences were noted between the self-reported and observed ratings immediately after fire suppression training. These findings support the use of direct observation to provide estimates of ratings of perceived exertion during fire suppression training.
Enjoyment Perception during Exercise with Aerobic Machines
Authors: Carraro Attilio , Gobbi Erica , Ferri Ilaria , Benvenuti Paolo , Zanuso Silvano
Published: July 2014

This study investigated enjoyment and naturalness of movement perceived during short bouts of exercise with three aerobic machines: treadmill, elliptical crosstrainer, and Vario. The participants were 72 experienced and 60 inexperienced users. Immediately after the exercise with each machine, they filled in a 12-item form of the Physical Activity Enjoyment Scale (PACES) and a Visual Analogue Scales (VAS) about naturalness of movement. Results showed significant within-subjects differences on all scales; exercise with the treadmill and Vario were perceived to be similarly enjoyable and more enjoyable and natural in comparison with the elliptical crosstrainer. Differences in naturalness ratings between experienced and inexperienced users were observed. Exercise was not equally enjoyable when performed with different aerobic machines, and this should be considered by professionals when prescribing aerobic training to enhance motivation and adherence.
Polymer Supported Triphenylphosphine-Palladium Acetate Complex PS-TPP-Pd(OAc)2 as a Heterogeneous and Reusable Catalyst for Indirect Reductive Amination of Aldehydes
Authors: Ekbote Sunil , Gadge Sandip , Bhanage Bhalchandra
Published: July 2014

Indirect reductive amination of aldehydes, catalyzed by polymer supported triphenylphosphine-palladium acetate complex PS-TPP-Pd(OAc)2 catalyst have been developed. The imine is prepared with molecular sieves in the first stage, followed by reduction with potassium formate catalyzed by PS-TPP-Pd(OAc)2. The recovered catalyst could be reused for four consecutive cycles without loss in activity and provided an excellent yield of the desired products.
The Entropy-Based Quantum Metric
Authors: Balian Roger
Published: July 2014

The von Neumann entropy S( D ^ ) generates in the space of quantum density matrices D ^ the Riemannian metric ds2 = −d2S( D ^ ), which is physically founded and which characterises the amount of quantum information lost by mixing D ^ and D ^ + d D ^ . A rich geometric structure is thereby implemented in quantum mechanics. It includes a canonical mapping between the spaces of states and of observables, which involves the Legendre transform of S( D ^ ). The Kubo scalar product is recovered within the space of observables. Applications are given to equilibrium and non equilibrium quantum statistical mechanics. There the formalism is specialised to the relevant space of observables and to the associated reduced states issued from the maximum entropy criterion, which result from the exact states through an orthogonal projection. Von Neumann’s entropy specialises into a relevant entropy. Comparison is made with other metrics. The Riemannian properties of the metric ds2 = −d2S( D ^ ) are derived. The curvature arises from the non-Abelian nature of quantum mechanics; its general expression and its explicit form for q-bits are given, as well as geodesics.
Cloning and Expression Characteristics of the Pig Stra8 Gene
Authors: Wang Xiaoyan , Chen Tingfeng , Song Chengyi , Gao Bo , Zhang Yani
Published: July 2014

Stra8 (Stimulated by Retinoic Acid 8) is considered a meiotic gatekeeper gene. Using reverse transcriptase PCR and rapid amplification of cDNA ends (RACE), the complete sequence of the pig Stra8 gene was cloned. Bioinformatics analyses of this sequence were performed. Using semi-quantitative methods, the expression characteristics of Stra8 in Testis, cauda epididymis, body epididymis, caput epididymis, seminal vesicles, prostate gland, Cowper’s gland, heart, liver, spleen, lung, kidney, stomach, hypothalamus, pituitary gland, cerebrum, cerebellum, and hippocampus of adult Meishan boar and sow tissues were examined. The expression pattern in the testis of 2-, 30-, 60-, 90-, and 150-day old Meishan boars were analyzed using real-time PCR. We constructed a eukaryotic expression vector for the Stra8 gene and used it to transfect NIH-3T3 cells and third generation pig spermatogonial stem cells (SSCs) cultured in vitro. Testes weight and sperm count in the cauda epididymis were evaluated at various time points. The results showed that the length of the pig Stra8 gene cDNA was 1444 bp encoding 366 amino acids with one typical helix-loop-helix (HLH) domain. It is testes-specific expression. Expression was first detected in boar testis starting at day 2, and its expression significantly (p < 0.05) increased with age and body weight. When NIH-3T3 cells and pig SSCs were transfected with the eukaryotic expression vector EGFP (enhanced green fluorescent protein)-N1-pStra8, it was expressed in the cytoplasm of NIH-3T3 cells. However, in SSCs, Stra8 was expressed predominantly in cytoplasm and few in nucleus. Our data suggest that perhaps Stra8 acts as a transcription factor to initiate meiosis in young boar.
Baicalin Ameliorates H2O2 Induced Cytotoxicity in HK-2 Cells through the Inhibition of ER Stress and the Activation of Nrf2 Signaling
Authors: Lin Miao , Li Long , Zhang Yi , Zheng Long , Xu Ming , Rong Ruiming , Zhu Tongyu
Published: July 2014

Renal ischemia-reperfusion injury plays a key role in renal transplantation and greatly affects the outcome of allograft. Our previous study proved that Baicalin, a flavonoid glycoside isolated from Scutellaria baicalensis, protects kidney from ischemia-reperfusion injury. This study aimed to study the underlying mechanism in vitro. Human renal proximal tubular epithelial cell line HK-2 cells were stimulated by H2O2 with and without Baicalin pretreatment. The cell viability, apoptosis and oxidative stress level were measured. The expression of endoplasmic reticulum (ER) stress hallmarks, such as binding immunoglobulin protein (BiP) and C/EBP homologous protein (CHOP), were analyzed by western blot and real-time PCR. NF-E2-related factor 2 (Nrf2) expression was also measured. In the H2O2 group, cell viability decreased and cell apoptosis increased. Reactive Oxygen Species (ROS) and Glutathione/Oxidized Glutathione (GSH/GSSG) analysis revealed increased oxidative stress. ER stress and Nrf2 signaling also increased. Baicalin pretreatment ameliorated H2O2-induced cytotoxicity, reduced oxidative stress and ER stress and further activated the anti-oxidative Nrf2 signaling pathway. The inducer of ER stress and the inhibitor of Nrf2 abrogated the protective effects, while the inhibitor of ER stress and the inducer of Nrf2 did not improve the outcome. This study revealed that Baicalin pretreatment serves a protective role against H2O2-induced cytotoxicity in HK-2 cells, where the inhibition of ER stress and the activation of downstream Nrf2 signaling are involved.
Applications of Biosurfactants in the Petroleum Industry and the Remediation of Oil Spills
Authors: Silva Rita , Almeida Darne , Rufino Raquel , Luna Juliana , Santos Valdemir , Sarubbo Leonie
Published: July 2014

Petroleum hydrocarbons are important energy resources. However, petroleum is also a major pollutant of the environment. Contamination by oil and oil products has caused serious harm, and increasing attention has been paid to the development and implementation of innovative technologies for the removal of these contaminants. Biosurfactants have been extensively used in the remediation of water and soil, as well as in the main stages of the oil production chain, such as extraction, transportation, and storage. This diversity of applications is mainly due to advantages such as biodegradability, low toxicity and better functionality under extreme conditions in comparison to synthetic counterparts. Moreover, biosurfactants can be obtained with the use of agro-industrial waste as substrate, which helps reduce overall production costs. The present review describes the potential applications of biosurfactants in the oil industry and the remediation of environmental pollution caused by oil spills.
The Critical Role of Membrane Cholesterol in Salmonella-Induced Autophagy in Intestinal Epithelial Cells
Authors: Huang Fu-Chen
Published: July 2014

It was previously observed that plasma membrane cholesterol plays a critical role in the Salmonella-induced phosphatidylinositol 3-kinase-dependent (PI3K)-dependent anti-inflammatory response in intestinal epithelial cells (IECs). The PI3K/Akt pathway is associated with autophagy which has emerged as a critical mechanism of host defense against several intracellular bacterial pathogens. Plasma membrane contributes directly to the formation of early Atg16L1-positive autophagosome precursors. Therefore, this study aimed to investigate the role of plasma membrane cholesterol on the Salmonella-induced autophagy in IECs. By using methyl-beta-cyclodextrin (MBCD), it was demonstrated that disruption of membrane cholesterol by MBCD enhanced NOD2 and Atg16L1 proteins expression in membrane, and autophagic LC3II proteins expression and LC3 punctae in Salmonella-infected Caco-2 cells, which was counteracted by Atg16L1 siRNA. Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) siRNA enhanced the Salmonella-induced activation of Akt in Caco-2 cells. However, inhibitors of Akt or extracellular signal-regulated kinases (ERK) had no significant effect on Salmonella-induced autophagy Beclin 1 or LC3 proteins expression. In conclusion, our study suggests that cholesterol accumulation in the plasma membrane at the entry site of Salmonella results in the formation of Salmonella-containing vacuole (SCV) and decreased autophagy. Our results offer mechanistic insights on the critical role of membrane cholesterol in the pathogenesis of Salmonella infection in intestinal epithelial cells and the therapeutic potential of its antagonists.
Fucoxanthin Enhances the Level of Reduced Glutathione via the Nrf2-Mediated Pathway in Human Keratinocytes
Authors: Zheng Jian , Piao Mei , Kim Ki , Yao Cheng , Cha Ji , Hyun Jin
Published: July 2014

Fucoxanthin, a natural carotenoid, is abundant in seaweed with antioxidant properties. This study investigated the role of fucoxanthin in the induction of antioxidant enzymes involved in the synthesis of reduced glutathione (GSH), synthesized by glutamate-cysteine ligase catalytic subunit (GCLC) and glutathione synthetase (GSS), via Akt/nuclear factor-erythroid 2-related (Nrf2) pathway in human keratinocytes (HaCaT) and elucidated the underlying mechanism. Fucoxanthin treatment increased the mRNA and protein levels of GCLC and GSS in HaCaT cells. In addition, fucoxanthin treatment promoted the nuclear translocation and phosphorylation of Nrf2, a transcription factor for the genes encoding GCLC and GSS. Chromatin immune-precipitation and luciferase reporter gene assays revealed that fucoxanthin treatment increased the binding of Nrf2 to the antioxidant response element (ARE) sequence and transcriptional activity of Nrf2. Fucoxanthin treatment increased phosphorylation of Akt (active form), an up-regulator of Nrf2 and exposure to LY294002, a phosphoinositide 3-kinase (PI3K)/Akt inhibitor, suppressed the fucoxanthin-induced activation of Akt, Nrf2, resulting in decreased GCLC and GSS expression. In accordance with the effects on GCLC and GSS expression, fucoxanthin induced the level of GSH. In addition, fucoxanthin treatment recovered the level of GSH reduced by ultraviolet B irradiation. Taken together, these findings suggest that fucoxanthin treatment augments cellular antioxidant defense by inducing Nrf2-driven expression of enzymes involved in GSH synthesis via PI3K/Akt signaling.
An Erbium-Based Bifuctional Heterogeneous Catalyst: A Cooperative Route Towards C-C Bond Formation
Authors: Oliverio Manuela , Costanzo Paola , Macario Anastasia , De Luca Giuseppina , Nardi Monica , Procopio Antonio
Published: July 2014

Heterogeneous bifuctional catalysts are multifunctional synthetic catalysts enabling efficient organic transformations by exploiting two opposite functionalities without mutual destruction. In this paper we report the first Er(III)-based metallorganic heterogeneous catalyst, synthesized by post-calcination MW-assisted grafting and modification of the natural aminoacid L-cysteine. The natural acid–base distance between sites was maintained to assure the cooperation. The applicability of this new bifunctional heterogeneous catalyst to C-C bond formation and the supposed mechanisms of action are discussed as well.
Strategy for Designing a Synthetic Tumor Vaccine: Multi-Component, Multivalency and Antigen Modification
Authors: Huang Zhi-Hua , Sun Zhan-Yi , Gao Yue , Chen Pu-Guang , Liu Yan-Fang , Chen Yong-Xiang , Li Yan-Mei
Published: July 2014

Synthetic tumor vaccines have been proven to be promising for cancer immunotherapy. However, the limitation of the specificity and efficiency of the synthetic tumor vaccines need further improvements. To overcome these difficulties, additional tumor-associated targets need to be identified, and optimized structural designs of vaccines need to be elaborated. In this review, we summarized the main strategies pursued in the design of synthetic tumor vaccines, such as multi-component, multivalency, antigen modification and other possible ways to improve the efficiency of synthetic tumor vaccines.
From the “Damsel in Distress” to Girls' Games and Beyond
Authors: King Alyson E. , Douai Aziz
Published: July 2014

In this chapter, the authors critically assess the gendered nature of the products developed by the computer gaming industry. The chapter takes a historiographical approach to examining the nature of children's video and computer games as a type of toy that immerses children into current gender stereotypes even as they hold the potential for social change. New ways of bridging the gap between stereotypes and change is explored through a virtual world for children. In addition to an introductory section, the chapter is organized in three main sections: First, the authors place existing computer and video games into a broad and historical context. Second, the chapter takes into consideration feminist critiques of video games for adults. Third, the authors analyze the case of WebkinzWorld, a toy-based social-networking portal offering less gendered video game environments for kids. The authors argue that this mixed method analysis is important not only for computer game designers and marketers who aim to appeal to broad demographics, but also for educators, parents, and caregivers who need to understand the underlying or hidden messages of games for children.
Women and Men in Computer Science
Authors: Denner Jill , Ortiz Eloy , Werner Linda
Published: July 2014

Playing digital games is described as a pathway to computer science (CS) classes and majors, but not all gamers want to study CS. The goal of this chapter is to explore which gaming motivations and practices are most strongly related to an interest in studying computer science, and whether the connection between gaming and computer science is similar for men and women. The data are from 545 male and female gamers taking an introductory computer science class at one of 15 community colleges in the US. Survey responses were analyzed to provide a picture of what, how often, and why they play, and interviews from 39 of the most avid gamers were analyzed for why and how they play. The results show that, on average, men play more frequently than women, and there are gender differences in the type of games they like to play and why they play them. However, playing more frequently was not associated with greater interest in studying CS for either gender. Interest in CS was highest among men who were motivated to play in order to increase skills, be with friends, connect with the game features, and by the art or graphics. However, CS interest was highest among women who consider themselves to be more serious gamers, play racing and puzzle games, play on a game console, and are motivated by fun, relaxation and social interaction. The results can inform efforts to increase the number of women that pursue computer science. The chapter concludes with recommendations for future research on how game play and interest in CS are related.
The Only Girl in the Class!
Authors: Elliott Lauren , Prescott Julie
Published: July 2014

Four female students studying a games course at one UK University took part in a qualitative study of face-to-face semi-structured interviews. Although a small sample, the study provided an interesting insight into the experiences of the females on the course as well as their views of entering (or at least potentially entering) the male dominated computer games industry. The findings related by the chapter reveal that females choose to study games because they enjoyed playing games. Despite all participants experiencing the course positively, there was some apprehension about going into the industry. Interestingly, the study suggests the male dominated working environment may be off-putting to women, even to women studying and interested in going into that area of work. The main themes that emerged in regard to the negativity associated with the industry were the long hours culture and potential sexism within the industry.