bluuebunny/crossref_metadata_2025 huggingface dataset:
Polymer nanocomposites with improved resistance to ionizing radiation
Authors: Borjanović Vesna , Bistričić Lahorija , Mikac Lara , McGuire Gary E. , Zamboni Ivana , Jakšić Milko , Shenderova Olga
Published: June 2012

In the present study, three different nanocomposites of poly(dimethylsiloxane) (PDMS) with 1 wt. % of nanoparticles of detonation nanodiamond (DND) (PDMS-DNDS), zinc oxide (ZnO) (PDMS-ZnO), and single-walled carbon nanotubes (SWNTs) (PDMS-SWNTs) were irradiated under vacuum at room temperature with a 2 MeV proton beam with fluences in the 1013–1015 cm−2 range. Modification of the structures and properties of the nanocomposite materials were monitored as a function of proton fluence. Specifically, the vibrational dynamics of PDMS nanocomposites for unirradiated and irradiated samples were investigated using Raman and Fourier transform infrared spectroscopy in the attenuated total reflection mode (FTIR-ATR) and compared. The results were also compared with the results obtained for the unirradiated/irradiated pure PDMS polymer. The Raman and FTIR-ATR spectra of the PDMS nanocomposites exhibit an overall reduction in intensity of the characteristic vibrational bands of the irradiated samples. However, an important difference between the irradiated pure PDMS versus PDMS nanocomposites’ Raman and FTIR spectra appeared; comparable structural degradation of polymer nanocomposites with ZnO, DND, and SWNT fillers takes place at least at 1 or even 2 orders of magnitude higher fluence than for pure PDMS, indicating the potential use of ZnO-based, DND-based, and SWNT-based polymer composites in high radiation environments. The highest resistance to radiation was demonstrated for PDMS-ZnO samples. Since the benefit is realized at a low loading, the cost of the nanocomposite can be kept low and the polymer retains the other beneficial properties that make them attractive.
Correlation between Mutations in
liaFSR
of Enterococcus faecium and MIC of Daptomycin: Revisiting Daptomycin Breakpoints
Authors: Munita Jose M. , Panesso Diana , Diaz Lorena , Tran Truc T. , Reyes Jinnethe , Wanger Audrey , Murray Barbara E. , Arias Cesar A.
Published: June 2012

Mutations in
liaFSR
, a three-component regulatory system controlling cell-envelope stress response, were recently linked with the emergence of daptomycin (DAP) resistance in enterococci. Our previous work showed that a
liaF
mutation increased the DAP MIC of a vancomycin-resistant
Enterococcus faecalis
strain from 1 to 3 μg/ml (the DAP breakpoint is 4 μg/ml), suggesting that mutations in the
liaFSR
system could be a pivotal initial event in the development of DAP resistance. With the hypothesis that clinical enterococcal isolates with DAP MICs between 3 and 4 μg/ml might harbor mutations in
liaFSR
, we studied 38
Enterococcus faecium
bloodstream isolates, of which 8 had DAP MICs between 3 and 4 μg/ml by Etest in Mueller-Hinton agar. Interestingly, 6 of these 8 isolates had predicted amino acid changes in the LiaFSR system. Moreover, we previously showed that among 6 DAP-resistant
E. faecium
isolates (MICs of >4 μg/ml), 5 had mutations in
liaFSR
. In contrast, none of 16
E. faecium
isolates with a DAP MIC of ≤2 μg/ml harbored mutations in this system (
P
< 0.0001). All but one isolate with
liaFSR
changes exhibited DAP MICs of ≥16 μg/ml by Etest using brain heart infusion agar (BHIA), a medium that better supports enterococcal growth. Our findings provide a strong association between DAP MICs within the upper susceptibility range and mutations in the
liaFSR
system. Concomitant susceptibility testing on BHIA may be useful for identifying these
E. faecium
first-step mutants. Our results also suggest that the current DAP breakpoint for
E. faecium
may need to be reevaluated.
Contribution of Urease to Colonization by Shiga Toxin-Producing Escherichia coli
Authors: Steyert Susan R. , Kaper James B.
Published: June 2012

Shiga toxin-producing
Escherichia coli
(STEC) is a food-borne pathogen with a low infectious dose that colonizes the colon in humans and can cause severe clinical manifestations such as hemolytic-uremic syndrome. The urease enzyme, encoded in the STEC chromosome, has been demonstrated to act as a virulence factor in other bacterial pathogens. The NH
3
produced as urease hydrolyzes urea can aid in buffering bacteria in acidic environments as well as provide an easily assimilated source of nitrogen that bacteria can use to gain a metabolic advantage over intact microflora. Here, we explore the role of urease in STEC pathogenicity. The STEC urease enzyme exhibited maximum activity near neutral pH and during the stationary-growth phase. Experiments altering growth conditions performed with three phylogenetically distinct urease-positive strains demonstrated that the STEC
ure
gene cluster is inducible by neither urea nor pH but does respond to nitrogen availability. Quantitative reverse transcription-PCR (qRT-PCR) data indicate that nitrogen inhibits the transcriptional response. The deletion of the
ure
gene locus was constructed in STEC strain 88-0643, and the
ure
mutant was used with the wild-type strain in competition experiments in mouse models to examine the contribution of urease. The wild-type strain was twice as likely to survive passage through the acidic stomach and demonstrated an enhanced ability to colonize the intestinal tract compared to the
ure
mutant strain. These
in vivo
experiments reveal that, although the benefit STEC gains from urease expression is modest and not absolutely required for colonization, urease can contribute to the pathogenicity of STEC.
Age and structure of the Crevice pluton: overlapping orogens in west-central Idaho?
Authors: Gray Keith D. , Watkinson A. John , Gaschnig Richard M. , Isakson Vincent H.
Published: June 2012

New U–Pb zircon geochronology from the Riggins region of west-central Idaho refines the timing of contractional deformation across the Salmon River suture zone (SRSZ), a broad north- to northeast-striking belt (>25 km wide) of high strain recording Jura-Cretaceous island-arc–continent collision. Laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS) yields mid-Cretaceous crystallization ages on formerly undated plutonic rocks sampled from the Salmon River canyon. In the Crevice pluton (∼105 Ma), the development of steep to moderate northerly striking gneissic foliation (S1) was followed by tops-to-the-west slip on shallow mylonitic shear zones (S2) and brittle overprinting via systematic joints (Jn) of regional extent. Together, these structures form the pluton’s internal architecture. Subvertical gneissic foliation in the adjacent Looking Glass pluton (∼92 Ma) indicates ductile deformation was ongoing in the Late Cretaceous. Prior to this investigation, penetrative fabrics in local arc volcanogenic, plutonic, and continental rocks have been unequivocally linked to post-collisional dextral transpression on the narrow (<10 km wide) western Idaho shear zone (WISZ). As an alternative to this model which requires spatially overlapping but temporally distinct orogenic belts (WISZ–SRSZ), we consider a protracted history whereby regional synmetamorphic structures accumulated over a pre-118 Ma to post-92 Ma interval without an overprinting orogen-scale ductile shear zone. In our view, a progressive deformation history more accurately accounts for the time-transgressive nature and structural continuity of fabrics observed across the arc–continent transition. This tectonic history proposed for western Idaho may be analogous to other long-lived accretionary margins in the North American Cordillera (e.g., Omineca Belt of southeastern British Columbia).
U–Pb zircon age of an Ordovician tuff in southeast Yukon: implications for the age of the Cambrian–Ordovician boundary1Yukon Geological Survey Contribution 013.2Geological Survey of Canada Earth Science Sector (ESS) Contribution 20110362.
Authors: Pigage L.C. , Crowley J.L. , Pyle L.J. , Abbott J.G. , Roots C.F. , Schmitz M.D.
Published: June 2012

Three conodont fossil occurrences stratigraphically above and below a rhyolitic tuff in the Lower Ordovician Crow Formation, southeast Yukon, constrain the tuff to the early Tremadocian Rossodus manitouensis Zone and possibly the Rossodus tenuis Zone. U–Pb dates were obtained from zircon from the tuff that was imaged with cathodoluminescence and chemically abraded to reduce the likelihood of dating grains that contain older components or suffered Pb loss, respectively. Six dates from grains with oscillatory parallel zoning are equivalent, with a weighted mean 206Pb/238U date of 491.04 ± 0.13 Ma. These grains are interpreted as being primary volcanic crystals, and the date is therefore taken as the depositional age of the tuff. Four other dates from grains with sector zoning are slightly older, up to 492.0 Ma, and are interpreted as inherited or recycled from earlier volcanics. The currently defined Cambrian–Ordovician boundary is inferred to be below the tuff and separated from it by at least two conodont biostratigraphic zones that are estimated to span at least 2.25 Ma based on the top of the Rhabdinopora flabelliformis parabola graptolite zone being older than the base of the Rossodus tenuis conodont zone. We interpret the evidence in southeast Yukon to suggest that the global Cambrian–Ordovician boundary is older (>493.3 Ma) than previous estimates of ∼488 and 491 Ma based upon legacy 207Pb/206Pb zircon ages.
TORSION VECTOR AND TORSION AXIAL-VECTOR IN VAN STOCKUM SPACETIME
Authors: GAD RAGAB M.
Published: June 2012

In this paper, we work with teleparallel gravity and show that the values of the torsion vector and the torsion axial-vector depend on the choice of the tetrad field. We choose two different sets of tetrad fields, each of them satisfies the tetrad's conditions and leads to the Van Stockum spacetime. We obtain expressions for the torsion vector and the torsion axial-vector. In addition, we found that the obtained expressions are quite different for the two sets of tetrad fields. For the spacetime under consideration, if the metric coefficients are assumed to be functions of t only, it is then shown that the torsion axial-vector vanishes completely and the torsion vector still depends on the choice of tetrad fields. Finally, we found the spin precession of a Dirac particle in the spacetime under consideration.
INTERFERENCE EFFECTS, TIME REVERSAL VIOLATION AND SEARCH FOR NEW PHYSICS IN HADRONIC WEAK DECAYS
Authors: AJALTOUNI Z. J. , DI SALVO E.
Published: June 2012

We propose some methods for studying hadronic sequential two-body decays involving more spinning particles. It relies on the analysis of T-odd and T-even asymmetries, which are related to interference terms. The latter asymmetries turn out to be as useful as the former ones in inferring time reversal violating observables; these in turn may be sensitive, under some particular conditions, to possible contributions beyond the standard model. Our main result is that one can extract such observables even after integrating the differential decay width over almost all of the available angles. Moreover we find that the correlations based exclusively on momenta are quite general, since they provide as much information as those involving one or more spins. We generalize some methods already proposed in the literature for particular decay channels, but we also pick out a new kind of time reversal violating observables. Our analysis could be applied, for example, to data of LHCb experiment.
Analysis of Workload Behavior in Scientific and Historical Long-Term Data Repositories
Authors: Adams Ian F. , Storer Mark W. , Miller Ethan L.
Published: June 2012

The scope of archival systems is expanding beyond cheap tertiary storage: scientific and medical data is increasingly digital, and the public has a growing desire to digitally record their personal histories. Driven by the increase in cost efficiency of hard drives, and the rise of the Internet, content archives have become a means of providing the public with fast, cheap access to long-term data. Unfortunately, designers of purpose-built archival systems are either forced to rely on workload behavior obtained from a narrow, anachronistic view of archives as simply cheap tertiary storage, or extrapolate from marginally related enterprise workload data and traditional library access patterns.

To close this knowledge gap and provide relevant input for the design of effective long-term data storage systems, we studied the workload behavior of several systems within this expanded archival storage space. Our study examined several scientific and historical archives, covering a mixture of purposes, media types, and access models---that is, public versus private. Our findings show that, for more traditional private scientific archival storage, files have become larger, but update rates have remained largely unchanged. However, in the public content archives we observed, we saw behavior that diverges from the traditional “write-once, read-maybe” behavior of tertiary storage. Our study shows that the majority of such data is modified---sometimes unnecessarily---relatively frequently, and that indexing services such as Google and internal data management processes may routinely access large portions of an archive, accounting for most of the accesses. Based on these observations, we identify areas for improving the efficiency and performance of archival storage systems.
Comparison of Retinal Nerve Fiber Layer Thickness Measurements in Healthy Subjects Using Fourier and Time Domain Optical Coherence Tomography
Authors: Pinilla Isabel , Garcia-Martin Elena , Idoipe Miriam , Sancho Eva , Fuertes Isabel
Published: June 2012

Purpose. To compare the retinal nerve fiber layer (RNFL) measurements using two different ocular coherence tomography (OCT) devices: Cirrus Fourier domain OCT and Stratus time domain OCT. To analyze reproducibility of Fourier domain measurements in healthy subjects.Methods. One hundred and thirty-two eyes of 132 healthy subjects were scaned on the same day with both instruments, separated by 10 minutes from each other. Thickness of quadrant, average and the 12 different areas around the optic nerve were compared between Cirrus and Stratus. Repeatability, intraclass correlation coefficients (ICCs), and coefficients of variation (COVs) were calculated in RNFL measurements provided by Fourier domain device.Results. The average thickness in the optic cube was 95.50 μm using Cirrus and 97.85 μm using Stratus. Average thickness and temporal quadrant showed significant differences using Cirrus and Stratus methods. Reproducibility was better with Fourier domain OCT (mean COV of 4.54%) than with Stratus time-domain OCT (mean COV of 5.57%).Conclusions. Both scan options give reproducible RNFL thickness measurement, but there are differences between them. Measurements obtained using Fourier domain device show better reproducibility.
Parachute-Payload System Flight Dynamics and Trajectory Simulation
Authors: Guglieri Giorgio
Published: June 2012

The work traces a general procedure for the design of a flight simulation tool still representative of the major flight physics of a parachute-payload system along decelerated trajectories. An example of limited complexity simulation models for a payload decelerated by one or more parachutes is given, including details and implementation features usually omitted as the focus of the research in this field is typically on the investigation of mission design issues, rather than addressing general implementation guidelines for the development of a reconfigurable simulation tool. The dynamics of the system are modeled through a simple multibody model that represents the expected behavior of an entry vehicle during the terminal deceleration phase. The simulators are designed according to a comprehensive vision that enforces the simplification of the coupling mechanism between the payload and the parachute, with an adequate level of physical insight still available. The results presented for a realistic case study define the sensitivity of the simulation outputs to the functional complexity of the mathematical model. Far from being an absolute address for the software designer, this paper tries to contribute to the area of interest with some technical considerations and clarifications.
The Antioxidant Effects of a Polyphenol-Rich Grape Pomace ExtractIn VitroDo Not CorrespondIn VivoUsing Exercise as an Oxidant Stimulus
Authors: Veskoukis Aristidis S. , Kyparos Antonios , Nikolaidis Michalis G. , Stagos Dimitrios , Aligiannis Nektarios , Halabalaki Maria , Chronis Konstantinos , Goutzourelas Nikolaos , Skaltsounis Leandros , Kouretas Dimitrios
Published: June 2012

Fruits, such as grapes, are essential food of the Mediterranean diet. Grape extracts have potent antioxidant and chemopreventive propertiesin vitro. Numerous studies have examined the effects of plant extract administration on redox status at rest in animals and humans but their results are controversial. However, there are no studies comparing thein vitroandin vivoeffects of plant extracts on oxidative stress using exercise as an oxidant stimulus. Thus, the aim of this study was to investigate whether a polyphenol-rich grape pomace extract of theVitis viniferaspecies possessesin vitroantioxidant properties and to examine whether these properties apply in anin vivomodel at rest and during exercise. Our findings indicate that the tested extract exhibits potentin vitroantioxidant properties because it scavenges the DPPH•and ABTS•+radicals and inhibits DNA damage induced by peroxyl and hydroxyl radicals. Administration of the extract in rats generally induced oxidative stress at rest and after exercise whereas exercise performance was not affected. Our findings suggest that the grape pomace extract does not behave with the same wayin vitroandin vivo.
The Human Mandible and the Origins of Speech
Authors: Daegling David J.
Published: June 2012

Among the unique traits of human mandibles is the finding of relatively greater utilization of cortical bone with respect to other hominoids. The functional significance of this trait is not plausibly linked to masticatory demands given the diminution of the masticatory musculature in human evolution and the behavioral universal of extraoral food preparation in recent humans. Similarly, the presence of more mandibular bone is not a correlated effect of systemic skeletal robusticity, since gracilization of the skeleton is a feature diagnostic of modern humans. The mandibular symphysis in modern humans is manifested as the chin, and it is here where cortical bone hypertrophy is most pronounced. The potential covariation between the expression of the chin and bone hypertrophy is explored in an attempt to clarify their respective biomechanical roles. Current developments in skeletal biomechanics implicate low magnitude, high frequency strains in bone hypertrophy. The physiology of speech production likely produces strains in mandibular bone of greater frequency and lesser magnitude than those associated with mastication. Consequently, language acquisition plausibly accounts for cortical hypertrophy in modern human mandibles. Its role in the evolution and development of the chin is less clear.
A Perturbed Projection Algorithm with Inertial Technique for Split Feasibility Problem
Authors: Dang Yazheng , Gao Yan , Han Yanli
Published: June 2012

This paper deals with the split feasibility problem that requires to find a point closest to a closed convex set in one space such that its image under a linear transformation will be closest to another closed convex set in the image space. By combining perturbed strategy with inertial technique, we construct an inertial perturbed projection algorithm for solving the split feasibility problem. Under some suitable conditions, we show the asymptotic convergence. The results improve and extend the algorithms presented in Byrne (2002) and in Zhao and Yang (2005) and the related convergence theorem.
Severe Accident Simulation of the Laguna Verde Nuclear Power Plant
Authors: Espinosa-Paredes Gilberto , Camargo-Camargo Raúl , Nuñez-Carrera Alejandro
Published: June 2012

The loss-of-coolant accident (LOCA) simulation in the boiling water reactor (BWR) of Laguna Verde Nuclear Power Plant (LVNPP) at 105% of rated power is analyzed in this work. The LVNPP model was developed using RELAP/SCDAPSIM code. The lack of cooling water after the LOCA gets to the LVNPP to melting of the core that exceeds the design basis of the nuclear power plant (NPP) sufficiently to cause failure of structures, materials, and systems that are needed to ensure proper cooling of the reactor core by normal means. Faced with a severe accident, the first response is to maintain the reactor core cooling by any means available, but in order to carry out such an attempt is necessary to understand fully the progression of core damage, since such action has effects that may be decisive in accident progression. The simulation considers a LOCA in the recirculation loop of the reactor with and without cooling water injection. During the progression of core damage, we analyze the cooling water injection at different times and the results show that there are significant differences in the level of core damage and hydrogen production, among other variables analyzed such as maximum surface temperature, fission products released, and debris bed height.
Plasticity of Corticospinal Neural Control after Locomotor Training in Human Spinal Cord Injury
Authors: Knikou Maria
Published: June 2012

Spinal lesions substantially impair ambulation, occur generally in young and otherwise healthy individuals, and result in devastating effects on quality of life. Restoration of locomotion after damage to the spinal cord is challenging because axons of the damaged neurons do not regenerate spontaneously. Body-weight-supported treadmill training (BWSTT) is a therapeutic approach in which a person with a spinal cord injury (SCI) steps on a motorized treadmill while some body weight is removed through an upper body harness. BWSTT improves temporal gait parameters, muscle activation patterns, and clinical outcome measures in persons with SCI. These changes are likely the result of reorganization that occurs simultaneously in supraspinal and spinal cord neural circuits. This paper will focus on the cortical control of human locomotion and motor output, spinal reflex circuits, and spinal interneuronal circuits and how corticospinal control is reorganized after locomotor training in people with SCI. Based on neurophysiological studies, it is apparent that corticospinal plasticity is involved in restoration of locomotion after training. However, the neural mechanisms underlying restoration of lost voluntary motor function are not well understood and translational neuroscience research is needed so patient-orientated rehabilitation protocols to be developed.
Containment Control of Multiagent Systems with Multiple Leaders and Noisy Measurements
Authors: Tang Zhao-Jun , Huang Ting-Zhu , Shao Jin-Liang
Published: June 2012

We consider the distributed containment control of multiagent systems with multiple stationary leaders and noisy measurements. A stochastic approximation type and consensus‐like algorithm is proposed to solve the containment control problem. We provide conditions under which all the followers can converge both almost surely and in mean square to the stationary convex hull spanned by the leaders. Simulation results are provided to illustrate the theoretical results.
AttenuatedSalmonella typhimuriumSV4089 as a Potential Carrier of Oral DNA Vaccine in Chickens
Authors: Jazayeri Seyed Davoud , Ideris Aini , Zakaria Zunita , Omar Abdul Rahman
Published: June 2012

AttenuatedSalmonellahas been used as a carrier for DNA vaccine. However,in vitroandin vivostudies on the bacteria following transfection of plasmid DNA were poorly studied. In this paper, eukaryotic expression plasmids encoding avian influenza virus (AIV) subtype H5N1 genes, pcDNA3.1/HA, NA, and NP, were transfected into an attenuatedSalmonella enteric typhimuriumSV4089.In vitrostability of the transfected plasmids intoSalmonellawere over 90% after 100 generations. The attenuatedSalmonellawere able to invade MCF-7 (1.2%) and MCF-10A (0.5%) human breast cancer cells. Newly hatched specific-pathogen-free (SPF) chicks were inoculated once by oral gavage with 109colony-forming unit (CFU) of the attenuatedSalmonella. No abnormal clinical signs or deaths were recorded after inoculation. Viable bacteria were detected 3 days after inoculation by plating from spleen, liver, and cecum. Fluorescentin situhybridization (FISH) and polymerase chain reaction (PCR) were carried out for confirmation.Salmonellawas not detected in blood cultures although serum antibody immune responses toSalmonellaO antiserum group D1 factor 1, 9, and 12 antigens were observed in all the inoculated chickens after 7 days up to 35 days. Our results showed that live attenuatedS. typhimuriumSV4089 harboring pcDNA3.1/HA, NA, and NP may provide a unique alternative as a carrier for DNA oral vaccine in chickens.
Existence Results for Solutions of Nonlinear Fractional Differential Equations
Authors: Yakar Ali , Koksal Mehmet Emir
Published: June 2012

This paper deals with theoretical and constructive existence results for solutions of nonlinear fractional differential equations using the method of upper and lower solutions
which generate a closed set. The existence of solutions for nonlinear fractional differential equations involving Riemann‐Liouville differential operator in a closed set is obtained by utilizing various types of coupled upper and lower solutions. Furthermore, these results are extended to the finite systems of nonlinear fractional differential equations leading to more general results.
Prenatal Diagnosis and Postnatal Findings of Cephalothoracopagus Janiceps Disymmetros: A Case Report
Authors: Rios Lívia Teresa Moreira , Araujo Júnior Edward , Nardozza Luciano Marcondes Machado , Nacaratto Daniela Cristina , Moron Antonio Fernandes , Martins Marília da Glória
Published: June 2012

Conjoined twins are rare variants of monozygotic twins, which result from an incomplete division of the embryonic disk. Cephalothoracopagus is a rare twin pregnancy described as imperfect fusion of the head and chest, but separated columns, limbs, and pelvis. They occur with incidence rates that range from 1 per 50,000 to 1 per 100,000 births; however, the incidence of the cephalothoracopagus variety is 1 per 58 conjoined twins. In the case of identical and symmetric faces caused by the orientations of the 2 notochordal axes that are perfectly ventroventral, they are called janiceps disymmetros. We present a prenatal diagnosis of a typical case of cephalothoracopagus janiceps disymmetros and the diagnostic confirmation by image and pathology exams.
Genetically Engineered Islets and Alternative Sources of Insulin-Producing Cells for Treating Autoimmune Diabetes: Quo Vadis?
Authors: Chou Feng-Cheng , Huang Shing-Hwa , Sytwu Huey-Kang
Published: June 2012

Islet transplantation is a promising therapy for patients with type 1 diabetes that can provide moment-to-moment metabolic control of glucose and allow them to achieve insulin independence. However, two major problems need to be overcome: (1) detrimental immune responses, including inflammation induced by the islet isolation/transplantation procedure, recurrence autoimmunity, and allorejection, can cause graft loss and (2) inadequate numbers of organ donors. Several gene therapy approaches and pharmaceutical treatments have been demonstrated to prolong the survival of pancreatic islet grafts in animal models; however, the clinical applications need to be investigated further. In addition, for an alternative source of pancreaticβ-cell replacement therapy, theex vivogeneration of insulin-secreting cells from diverse origins of stem/progenitor cells has become an attractive option in regenerative medicine. This paper focuses on the genetic manipulation of islets during transplantation therapy and summarizes current strategies to obtain functional insulin-secreting cells from stem/progenitor cells.
Production Costs and Markets for Pellet Chips: Case Studies in Northern Sweden
Authors: Eriksson Gunnar , Athanassiadis Dimitris , Bergström Dan , Nordfjell Tomas , Bergsten Urban
Published: June 2012

Increasing use of woody fuels requires that nontraditional types of raw materials are exploited, including logging residues and small-diameter trees. Although medium-scale combustors often use pellets, they could conceivably use dried chips of sufficiently narrow size distribution (henceforth pellet chips). The influence of the following factors on the relative cost-effectiveness of producing pellets and pellet chips was investigated for three plant sites in northern Sweden: (1) harvesting and transporting of forest residues; (2) the potential of existing energy plants to supply drying heat in periods of capacity surplus; (3) the distance to potential end-users. Data from the national forest inventory were used to estimate raw material costs. The resulting production costs were 144–176 $ per oven-dry tonnes (OD t) for pellets (27.4–33.5 $ MWh−1) and 143–173 $ OD t−1(27.2–33.0 $ MWh−1) for pellet chips, with harvesting, forwarding, chipping, and transporting of logging residues to the sites amounting to 114–122 $ OD t−1(21.7–23.2 $ MWh−1) for both fuels. Even though the differences in production costs were minor, the production of pellet chips requires significantly less electricity input per OD t of produced fuel. For cost reductions improved methods for wood fuel procurement, compacting and transporting of chips, small-scale low-temperature drying and foliage and bark separation are needed.
5‐Fluorouracil Encapsulated Chitosan Nanoparticles for pH‐Stimulated Drug Delivery: Evaluation of Controlled Release Kinetics
Authors: Tığlı Aydın R. Seda , Pulat Mehlika
Published: June 2012

Nanoparticles consisting of human therapeutic drugs are suggested as a promising strategy for targeted and localized drug delivery to tumor cells. In this study, 5‐fluorouracil (5‐FU) encapsulated chitosan nanoparticles were prepared in order to investigate potentials of localized drug delivery for tumor environment due to pH sensitivity of chitosan nanoparticles. Optimization of chitosan and 5‐FU encapsulated nanoparticles production revealed 148.8 ± 1.1 nm and 243.1 ± 17.9 nm particle size diameters with narrow size distributions, which are confirmed by scanning electron microscope (SEM) images. The challenge was to investigate drug delivery of 5‐FU encapsulated chitosan nanoparticles due to varied pH changes. To achieve this objective, pH sensitivity of prepared chitosan nanoparticle was evaluated and results showed a significant swelling response for pH 5 with particle diameter of ~450 nm. In vitro release studies indicated a controlled and sustained release of 5‐FU from chitosan nanoparticles with the release amounts of 29.1–60.8% due to varied pH environments after 408 h of the incubation period. pH sensitivity is confirmed by mathematical modeling of release kinetics since chitosan nanoparticles showed stimuli‐induced release. Results suggested that 5‐FU encapsulated chitosan nanoparticles can be launched as pH‐responsive smart drug delivery agents for possible applications of cancer treatments.
Harmonic Morphisms Projecting Harmonic Functions to Harmonic Functions
Authors: Mustafa M. T.
Published: June 2012

For Riemannian manifolds M and N, admitting a submersion ϕ with compact fibres, we introduce the projection of a function via its decomposition into
horizontal and vertical components. By comparing the Laplacians on M and N, we determine conditions under which a harmonic function on U = ϕ−1(V) ⊂ M projects down, via its horizontal component, to a harmonic function on V ⊂ N.
Are Classification Criteria for IgG4-RD Now Possible? The Concept of IgG4-Related Disease and Proposal of Comprehensive Diagnostic Criteria in Japan
Authors: Okazaki Kazuichi , Umehara Hisanori
Published: June 2012

Recent studies suggest simultaneous or metachronous lesions in multiorgans characterized by elevated serum levels of IgG4 and abundant infiltration of IgG4-positive plasma cells with various degrees of fibrosis. Two Japanese research committees for IgG4-RD, one from fibrosclerosis (Okazaki team) and the other from lymph proliferation (Umehara team) supported by the “Research Program for Intractable Disease” of the Ministry of Health, Labor, and Welfare of Japan, have agreed with the unified nomenclature as “IgG4-RD” and proposed the comprehensive diagnostic criteria (CDC) for IgG4-RD. Validation of the CDC demonstrated satisfactory sensitivity for the practical use of general physicians and nonspecialists but low sensitivity in the organs to be difficult in taking biopsy specimens such as type1 autoimmune pancreatitis (IgG4-related AIP), compared with IgG4-related sialadenitis/dacryoadenitis (Mikulicz's disease) and IgG4-related kidney disease. Although the diagnostic criteria covering all IgG4-RD are hard to be established, combination with the CDC and organ-specific diagnostic criteria should improve sensitivity.
Overcoming Barriers in the Management of Hypertension: The Experience of the Cardiovascular Health Program in Chilean Primary Health Care Centers
Authors: Sandoval Daniela , Bravo Miguel , Koch Elard , Gatica Sebastián , Ahlers Ivonne , Henríquez Oscar , Romero Tomás
Published: June 2012

Objective. To assess the blood pressure control and cardiovascular risk factors (CVRFs) in a population of hypertensive patients with access to care under a government-financed program, the Cardiovascular Health Program (CHP).Design. A cross-sectional and multicenter study.Setting. 52 primary care centers, metropolitan area of Santiago, Chile.Participants. 1,194 patients were selected by a systematic random sampling from a universe of 316,654 hypertensive patients.Key Measurements. Demographic information, blood pressure (BP) measurements, and CVRF were extracted from medical records of patients followed for a 12-month period.Results. 59.7% of patients reached target BP<140/90 mmHg. More women were captured in the sampling (2.1 : 1), achieving better BP control than men. Diabetic patients (26.4%) had worse BP control than nondiabetics. Antihypertensive medications were used in 91.5%, with multidrug therapy more frequent in patients with higher BP and more difficult control.Conclusions. The success in improving the BP control to values <140/90 mmHg from 45.3% to 59.7% underscores the contribution of this program in the Chilean primary care cardiovascular preventive strategies. However, fewer hypertensive men than women were captured by this program, and it is of concern the underperforming of BP control observed in diabetics.
MicroRNAs and the Regulation of Tau Metabolism
Authors: Hébert Sébastien S. , Sergeant Nicolas , Buée Luc
Published: June 2012

Abnormal regulation of tau phosphorylation and/or alternative splicing is associated with the development of a large (>20) group of neurodegenerative disorders collectively known as tauopathies, the most common being Alzheimer's disease. Despite intensive research, little is known about the molecular mechanisms that participate in the transcriptional and posttranscriptional regulation of endogenous tau, especially in neurons. Recently, we showed that mice lackingDicerin the forebrain displayed progressive neurodegeneration accompanied by disease-like changes in tau phosphorylation and splicing. Dicer is a key enzyme in the biogenesis of microRNAs (miRNAs), small noncoding RNAs that function as part of the RNA-induced silencing complex (RISC) to repress gene expression at the posttranscriptional level. We identified miR-16 and miR-132 as putative endogenous modulators of neuronal tau phosphorylation and tau exon 10 splicing, respectively. Interestingly, these miRNAs have been implicated in cell survival and function, whereas changes in miR-16/132 levels correlate with tau pathology in human neurodegenerative disorders. Thus, understanding how miRNA networks influence tau metabolism and possibly other biological systems might provide important clues into the molecular causes of tauopathies, particularly the more common but less understood sporadic forms.
Advances in Agronomic Management of Indian Mustard (Brassica juncea(L.) Czernj. Cosson): An Overview
Authors: Shekhawat Kapila , Rathore S. S. , Premi O. P. , Kandpal B. K. , Chauhan J. S.
Published: June 2012

India is the fourth largest oilseed economy in the world. Among the seven edible oilseeds cultivated in India, rapeseed-mustard contributes 28.6% in the total oilseeds production and ranks second after groundnut sharing 27.8% in the India’s oilseed economy. The mustard growing areas in India are experiencing the vast diversity in the agro climatic conditions and different species of rapeseed-mustard are grown in some or other part of the country. Under marginal resource situation, cultivation of rapeseed-mustard becomes less remunerative to the farmers. This results in a big gap between requirement and production of mustard in India. Therefore site-specific nutrient management through soil-test recommendation based should be adopted to improve upon the existing yield levels obtained at farmers field. Effective management of natural resources, integrated approach to plant-water, nutrient and pest management and extension of rapeseed-mustard cultivation to newer areas under different cropping systems will play a key role in further increasing and stabilizing the productivity and production of rapeseed-mustard. The paper reviews the advances in proper land and seedbed preparation, optimum seed and sowing, planting technique, crop geometry, plant canopy, appropriate cropping system, integrated nutrient management and so forth to meet the ever growing demand of oil in the country and to realize the goal of production of 24 million tonnes of oilseed by 2020 AD through these advanced management techniques.
Ginkgo Biloba Extract EGB761 Protects against Aging-Associated Diastolic Dysfunction in Cardiomyocytes of D-Galactose-Induced Aging Rat
Authors: Liu Jing , Wang Junhong , Chen Xiangjian , Guo Changqing , Guo Yan , Wang Hui
Published: June 2012

The aim of the present study was to make use of the artificially induced aging model cardiomyocytes to further investigate potential anti-aging-associated cellular diastolic dysfunction effects of EGB761 and explore underlying molecular mechanisms. Cultured rat primary cardiomyocytes were treated with either D-galactose or D-galactose combined with EGB761 for 48 h. After treatment, the percentage of cells positive for SA-β-gal, AGEs production, cardiac sarcoplasmic reticulum calcium pump (SERCA) activity, the myocardial sarcoplasmic reticulum calcium uptake, and relative protein levels were measured. Our results demonstrated that in vitro stimulation with D-galactose induced AGEs production. The addition of EGB761 significantly decreased the number of cells positive for SA-β-gal. Furthermore, decreased diastolic [Ca2+]i, curtailment of the time from the maximum concentration of Ca2+to the baseline level and increased reuptake of Ca2+stores in the SR were also observed. In addition, the level of p-Ser16-PLN protein as well as SERCA was markedly increased. The study indicated that EGb761 alleviates formation of AGEs products on SERCA2a in order to mitigate myocardial stiffness on one hand; on other hand, improve SERCA2a function through increase the amount of Ser16 sites PLN phosphorylation, which two hands finally led to ameliorate diastolic dysfunction of aging cardiomyocytes.
Evaluation of Hepatoprotective Effect of Leaves ofCassia sopheraLinn.
Authors: Mondal Arijit , Karan Sanjay Kumar , Singha Tanushree , Rajalingam D. , Maity Tapan Kumar
Published: June 2012

In the present study, the hepatoprotective activity of ethanolic extracts ofCassia sopheraLinn. leaves was evaluated against carbon-tetrachloride- (CCl4-) induced hepatic damage in rats. The extracts at doses of 200 and 400 mg/kg were administered orally once daily. The hepatoprotection was assessed in terms of reduction in histological damage, changes in serum enzymes, serum glutamate oxaloacetate transaminase (AST), serum glutamate pyruvate transaminase (ALT), serum alkaline phosphatase (ALP), total bilirubin, and total protein levels. The substantially elevated serum enzymatic levels of AST, ALT, ALP, and total bilirubin were restored towards the normalization significantly by the extracts. The decreased serum total protein level was significantly normalized. Silymarin was used as standard reference and exhibited significant hepatoprotective activity against carbon tetrachloride-induced hepatotoxicity in rats. The biochemical observations were supplemented with histopathological examination of rat liver sections. The results of this study strongly indicate thatCassia sopheraleaves have potent hepatoprotective action against carbon tetrachloride-induced hepatic damage in rats. This study suggests that possible activity may be due to the presence of flavonoids in the extracts.
A Scheme for Evaluating Feral Horse Management Strategies
Authors: Eberhardt L. L. , Breiwick J. M.
Published: June 2012

Context. Feral horses are an increasing problem in many countries and are popular with the public, making management difficult.Aims. To develop a scheme useful in planning management strategies.Methods. A model is developed and applied to four different feral horse herds, three of which have been quite accurately counted over the years.Key Results. The selected model has been tested on a variety of data sets, with emphasis on the four sets of feral horse data. An alternative, nonparametric model is used to check the selected parametric approach.Conclusions. A density-dependent response was observed in all 4 herds, even though only 8 observations were available in each case. Consistency in the model fits suggests that small starting herds can be used to test various management techniques.Implications. Management methods can be tested on actual, confined populations.
Integrating Interactive Web-Based Technology to Assess Adherence and Clinical Outcomes in Pediatric Sickle Cell Disease
Authors: Crosby Lori E. , Barach Ilana , McGrady Meghan E. , Kalinyak Karen A. , Eastin Adryan R. , Mitchell Monica J.
Published: June 2012

Research indicates that the quality of the adherence assessment is one of the best predictors for improving clinical outcomes. Newer technologies represent an opportunity for developing high quality standardized assessments to assess clinical outcomes such as patient experience of care but have not been tested systematically in pediatric sickle cell disease (SCD). The goal of the current study was to pilot an interactive web-based tool, the Take-Charge Program, to assess adherence to clinic visits and hydroxyurea (HU), barriers to adherence, solutions to overcome these barriers, and clinical outcomes in 43 patients with SCD age 6–21 years. Results indicate that the web-based tool was successfully integrated into the clinical setting while maintaining high patient satisfaction (>90%). The tool provided data consistent with the medical record, staff report, and/or clinical lab data. Participants reported that forgetting and transportation were major barriers for adherence to both clinic attendance and HU. A greater number of self-reported barriers(P<.01)and older age(P<.05)were associated with poorer clinic attendance and HU adherence. In summary, the tool represents an innovative approach to integrate newer technology to assess adherence and clinical outcomes for pediatric patients with SCD.
On a Third‐Order System of Difference Equations with Variable Coefficients
Authors: Stević Stevo , Diblík Josef , Iričanin Bratislav , Šmarda Zdeněk
Published: June 2012

We show that the system of three difference equations , , and , n ∈ ℕ0, where all elements of the sequences , , , n ∈ ℕ0, i ∈ {1,2, 3}, and initial values x−j, y−j, z−j, j ∈ {0,1, 2}, are real numbers, can be solved. Explicit formulae for solutions of the system are derived, and some consequences on asymptotic behavior of solutions for the case when coefficients are periodic with period three are deduced.
Cellular Reprogramming Employing Recombinant Sox2 Protein
Authors: Thier Marc , Münst Bernhard , Mielke Stephanie , Edenhofer Frank
Published: June 2012

Induced pluripotent stem (iPS) cells represent an attractive option for the derivation of patient-specific pluripotent cells for cell replacement therapies as well as disease modeling. To become clinically meaningful, safe iPS cells need to be generated exhibiting no permanent genetic modifications that are caused by viral integrations of the reprogramming transgenes. Recently, various experimental strategies have been applied to accomplish transgene-free derivation of iPS cells, including the use of nonintegrating viruses, episomal expression, or excision of transgenes after reprogramming by site-specific recombinases or transposases. A straightforward approach to induce reprogramming factors is the direct delivery of either synthetic mRNA or biologically active proteins. We previously reported the generation of cell-permeant versions of Oct4 (Oct4-TAT) and Sox2 (Sox2-TAT) proteins and showed that Oct4-TAT is reprogramming-competent, that is, it can substitute for Oct4-encoding virus. Here, we explore conditions for enhanced Sox2-TAT protein stabilization and functional delivery into somatic cells. We show that cell-permeant Sox2 protein can be stabilized by lipid-rich albumin supplements in serum replacement or low-serum-supplemented media. Employing optimized conditions for protein delivery, we demonstrate that Sox2-TAT protein is able to substitute for viral Sox2. Sox2-piPS cells express pluripotency-associated markers and differentiate into all three germ layers.
Fibroblast Growth Factor Receptor 2: Expression, Roles, and Potential As a Novel Molecular Target for Colorectal Cancer
Authors: Matsuda Yoko , Ueda Junji , Ishiwata Toshiyuki
Published: June 2012

The fibroblast growth factor receptor (FGFR) family consists of four members, named FGFR1, 2, 3, and 4. All 4 FGFRs and their ligands, fibroblast growth factors (FGFs), are expressed in colorectal cancer (CRC). Recent studies have shown that FGFR2 plays important roles in cancer progression; therefore, it is of great interest as a novel target for cancers. Expression of FGFR2 regulates migration, invasion, and growth in CRC. Expression of the FGFR2 isoform FGFR2 IIIb was associated with well-differentiated histological types, and its specific ligand, FGF7, enhanced angiogenesis and adhesion to type-IV collagen via FGFR2 IIIb in CRC. FGFR2 IIIc is detected in CRC, but its roles have not been well elucidated. Interactions between FGFR2 IIIb and IIIc and FGFs may play important roles in CRC via autocrine and/or paracrine signaling. Several kinds of molecular-targeting agents against FGFR2 have been developed; however, it is not clear how a cancer treatment can most effectively inhibit FGFR2 IIIb or FGFR2 IIIc, or both isoforms. The aim of this paper is to summarize the roles of FGFR2 and its isoforms in CRC and clarify whether they are potent therapeutic targets for CRC.
Experimental Evaluation of Sulfur Dioxide Absorption in Water Using Structured Packing
Authors: Chavez Rosa-Hilda , Flores-Alamo Nicolas , Guadarrama Javier de J.
Published: June 2012

An experimental study of hydrodynamic and mass transfer processes was carried out in an absorption column of 0.252 m diameter and 3.5 m of packed bed height developed by Mexican National Institute of Nuclear Research (ININby its acronym in Spanish) of stainless steel gauze corrugated sheet packing by means of SO2-air-water systems. The experiments results include pressure drop, flows capacity, liquid hold-up, SO2composition, and global mass transfer coefficient and mass transfer unit height by mass transfer generalized performance model in order to know the relationship between two-phase countercurrent flow and the geometry of packed bed. Experimental results at loading regimen are reported as well as model predictions. The average deviation between the measured values and the predicted values is±5% of 48-data-point absorption test. The development of structured packing has allowed greater efficiency of absorption and lower pressure drop to reduce energy consumption. In practice, the designs of equipment containing structured packings are based on approximations of manufacturer recommendations.