bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of International Classification of Diseases, Ninth Revision, Clinical Modification, Codes to Identify Inpatient Fall‐Related Injuries
Authors: Waters Teresa M. , Chandler A. Michelle , Mion Lorraine C. , Daniels Michael J. , Kessler Lori A. , Miller Stephen T. , Shorr Ronald I.
Published: November 2013

Objectives

To compare falls and fall‐related injuries that a fall evaluator or hospital incident report identified with injuries identified according to discharge International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) codes for the same set of inpatient episodes of care.

Design

Prospective, descriptive study.

Setting

Sixteen adult general medical and surgical units in a major urban teaching hospital.

Participants

All adults who sustained a fall with injury during a 5‐year period (380 falls with injury).

Measurements

Falls that a fall evaluator or hospital incident report identified were classified according to their injury severity. Discharge abstracts provided diagnosis codes (ICD‐9‐CM) for the discharge, including fall‐related injury codes.

Results

Three hundred forty‐three inpatient falls with injury (90.2%) resulted in temporary harm to the individual; the remaining 37 falls (9.8%) resulted in more‐serious harm. Sixteen of the 37 falls with injury extending hospitalization or resulting in death were identified using Centers for Medicare and Medicaid Services (CMS)‐targeted injury code ranges combined with present‐on‐admission indicators. Of the 21 falls with injury that were not identified, nine (42.9%) lacked documentation of any injury, and seven (33.3%) identified other injuries outside the CMS‐targeted injury code ranges.

Conclusion

The CMS‐targeted ICD‐9‐CM codes used to identify fall‐related injuries in claims data do not always detect the most‐serious falls.
The suitability of caffeinated drinks for children: a systematic review of randomised controlled trials, observational studies and expert panel guidelines
Authors: Ruxton C. H. S.
Published: November 2013

Background

The increased availability of caffeinated drinks raises questions about the level of caffeine that is appropriate for children, as well as the benefits and risks associated with their consumption.

Methods

Using the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines, this systematic review evaluates evidence from randomised controlled trials investigating the effects of caffeine on cognition, behaviour, mood and exercise performance in children. Observational studies and expert panel guidelines are also discussed.

Results

One hundred and nine studies were found, with 11 randomised controlled trials and 13 observational studies meeting the criteria. High caffeine intakes (e.g. >5 mg kg–1 body weight day–1) were associated with an increased risk of anxiety and withdrawal symptoms. However, smaller amounts were not linked with such effects and may benefit cognitive function and sports performance based on adult studies. The evidence suggests that children and adolescents should limit daily caffeine consumption to 2.5 mg kg–1 body weight day–1, equating to one or two cups of tea or one small cup of coffee. Lower contributors of caffeine, such as tea, may be more appropriate for children because they contribute to daily fluid intakes and provide flavonoids. By contrast, caffeinated soft drinks may be less suitable options for children as a result of their acidity, higher caffeine content, presence of added sugar (in some cases) and absence of bioactive compounds.

Conclusions

More studies are needed to determine the intakes that represent a risk and whether there may be benefits for alertness and sports performance with moderate intakes of caffeine.
The GLT‐1 (EAAT2; slc1a2) glutamate transporter is essential for glutamate homeostasis in the neocortex of the mouse
Authors: Bjørnsen Lars Petter , Hadera Mussie G. , Zhou Yun , Danbolt Niels C. , Sonnewald Ursula
Published: November 2013

Glutamate is the major excitatory neurotransmitter, and is inactivated by cellular uptake catalyzed mostly by the glutamate transporter subtypes GLT‐1 (EAAT2) and GLAST (EAAT1). Astrocytes express both GLT‐1 and GLAST, while axon terminals in the neocortex only express GLT‐1. To evaluate the role of GLT‐1 in glutamate homeostasis, we injected GLT‐1 knockout (KO) mice and wild‐type littermates with [1‐13C]glucose and [1,2‐13C]acetate 15 min before euthanization. Metabolite levels were analyzed in extracts from neocortex and cerebellum and 13C labeling in neocortex. Whereas the cerebellum in GLT‐1‐deficient mice had normal levels of glutamate, glutamine, and 13C labeling of metabolites, glutamate level was decreased but labeling from [1‐13C] glucose was unchanged in the neocortex. The contribution from pyruvate carboxylation toward labeling of these metabolites was unchanged. Labeling from [1,2‐13C] acetate, originating in astrocytes, was decreased in glutamate and glutamine in the neocortex indicating reduced mitochondrial metabolism in astrocytes. The decreased amount of glutamate in the cortex indicates that glutamine transport into neurons is not sufficient to replenish glutamate lost because of neurotransmission and that GLT‐1 plays a role in glutamate homeostasis in the cortex.

image

Glutamate is the major excitatory neurotransmitter, and is inactivated by uptake via GLT‐1 (EAAT2) and GLAST (EAAT1) transporters, while axon terminals in the neocortex only express GLT‐1. To evaluate the role of GLT‐1 in glutamate homeostasis, we used [1‐13C]glucose and [1,2‐13C]acetate injection and NMR spectroscopy. The results indicate that glutamine transport into neurons is not sufficient to replenish glutamate lost because of neurotransmission and that GLT‐1 plays a role in glutamate homeostasis in the neocortex.
The putative multidrug resistance proteinMRP‐7 inhibits methylmercury‐associated animal toxicity and dopaminergic neurodegeneration inCaenorhabditis elegans
Authors: VanDuyn Natalia , Nass Richard
Published: November 2013

Parkinson's disease (PD) is the most prevalent neurodegenerative motor disorder worldwide, and results in the progressive loss of dopamine (DA) neurons in the substantia nigra pars compacta. Gene–environment interactions are believed to play a significant role in the vast majority ofPDcases, yet the toxicants and the associated genes involved in the neuropathology are largely ill‐defined. Recent epidemiological and biochemical evidence suggests that methylmercury (MeHg) may be an environmental toxicant that contributes to the development ofPD. Here, we report that a gene coding for the putative multidrug resistance proteinMRP‐7 inCaenorhabditis elegansmodulates whole animal andDAneuron sensitivity to MeHg. In this study, we demonstrate that genetic knockdown ofMRP‐7 results in a twofold increase in Hg levels and a dramatic increase in stress response proteins associated with the endoplasmic reticulum, golgi apparatus, and mitochondria, as well as an increase in MeHg‐associated animal death. Chronic exposure to low concentrations of MeHg inducesMRP‐7 gene expression, while exposures inMRP‐7 genetic knockdown animals results in a loss ofDAneuron integrity without affecting whole animal viability. Furthermore, transgenic animals expressing a fluorescent reporter behind the endogenousMRP‐7 promoter indicate that the transporter is expressed inDAneurons. These studies show for the first time that a multidrug resistance protein is expressed inDAneurons, and its expression inhibits MeHg‐associatedDAneuron pathology.

image

Methylmercury (MeHg) exposure is a risk factor for Parkinson's disease. Yet, the molecular basis for Hg transport and neurotoxicity is poorly defined. Our studies identify the first multidrug resistance protein that is targeted to dopamine (DA) neurons. We show that the transporter inhibits MeHg‐associated accumulation of Hg, intracellular toxicant‐associated stress response, and DA neurodegeneration. This model should facilitate the identification of molecular pathways and potential therapeutic targets involved in MeHg‐associated dopamine neuron pathology. hsp = heat‐shock protein.
Meaning‐in‐life in nursing‐home patients: a valuable approach for enhancing psychological and physical well‐being?
Authors: Haugan Gørill
Published: November 2013

Aims and objectives

To investigate the associations between meaning‐in‐life and physical, emotional, functional and social well‐being in a cognitively intact nursing‐home population.

Background

Meaning‐in‐life is understood as an influential psychological variable that promotes health and well‐being; meaning‐in‐life has been found to be a mediating variable in both psychological and physical health.

Design and methods

The study employed a cross‐sectional design. Data were collected in 2008 and 2009 using the purpose‐in‐life test and theFACT‐G quality‐of‐life questionnaire. A total of 250 cognitively intact nursing‐home patients who met the inclusion criteria were approached and 202 attended. The hypothesised relationships between meaning and multidimensional well‐being were tested by means of structural equation modelling.

Results

The structural equation modelling model fit well with the present data, showing significant direct relationships between meaning‐in‐life and emotional and functional well‐being, and a significant mediated influence of meaning on social and physical well‐being.

Conclusion

Meaning‐in‐life is associated with all dimensions of well‐being and likely plays an important role in both emotional and physical well‐being.

Relevance to clinical practice

Facilitating patients' perceived meaning‐in‐life might help ease emotional distress and physical symptoms, thus fostering well‐being in cognitively intact nursing‐home patients. Therefore, advancing staff nurses' competence in facilitating meaningful involvement, connectedness, nurse–patient interaction and symptom management is important for care quality and global well‐being in nursing homes.
On the statistical model of the two-stage designs in bioequivalence assessment
Authors: Karalis Vangelis , Macheras Panos
Published: November 2013

Objectives

Two-stage clinical designs are currently recommended by the regulatory authorities for the assessment of bioequivalence (BE). A specific statistical methodology was recently proposed by the European Medicines Agency (EMA). The aims of this article are to elaborate on the suggested statistical design from the EMA and to compare it with the existing statistical methods reported in the literature.

Methods

Monte Carlo simulations were used to simulate the conditions of a two-stage BE design. The starting sample size was either 24 or 48, whereas the coefficient of variation of the within-subject variability was equal to 20% and 40%. Several geometric mean ratio levels of the BE metric were considered. Under each condition, 1 000 000 studies were simulated.

Key findings

The overall performance, in terms of percentage of BE acceptance, is identical. The additional term, ‘sequence × stage’, suggested in the EMA method is in most cases nonsignificant. The same results were obtained regardless of the type (fixed or random) of the effect applied to the ‘subjects’ term.

Conclusions

Any BE study either finished or in progress which relies on the existing literature methodology leads to the same percentage of BE acceptance as if it was analysed with the recently proposed EMA method.
Osteoarthritis of the hand II: chemistry, pharmacokinetics and pharmacodynamics of naproxen, and clinical outcome studies
Authors: Leung Garvin J , Rainsford K D , Kean Walter F
Published: November 2013

Objective

This article aims to review osteoarthritis of the hand and the role of the non-steroidal anti-inflammatory drug (NSAID) naproxen on its management. We discuss the chemical and pharmacological properties of naproxen and the NSAID class, with an emphasis on its mechanism and adverse reactions. In the context of part I of this paper in characterizing hand osteoarthritis (OA), we review clinical trials that have been conducted involving hand OA and naproxen.

Key findings

The therapeutic effect of NSAIDs stems from its role on inhibiting cyclo-oxygenase (COX)-1 or COX-2 enzyme activity in the body. These enzymes play a major role in maintaining several functions in the body and due NSAIDs' inhibitory effects; many principle adverse reactions occur with the use of NSAIDs such as: gastrointestinal tract issues, cardiovascular risks, renal, hepatic, central nervous system and cutaneous. Review of clinical trials involving naproxen and hand OA show that it is significantly more efficacious when compared with placebo.

These studies, along with the finding that naproxen is of least cardiovascular risk in the NSAID class, may show that it can be part of one of the approaches in managing the condition. It is important to note that the optimal NSAID to use varies for each individual. The finding that the use of naproxen leads to the smallest increase in cardiovascular risk appeals to those at-risk individuals who suffer from OA and require pharmacological treatment for relief.
Homocysteine in dogs with systemic inflammatory response syndrome
Authors: Patterson B. E. , Barr J. W. , Fosgate G. T. , Berghoff N. , Steiner J. M. , Suchodolski J. S. , Black D. M.
Published: November 2013

Objectives

To compare serum concentrations of homocysteine in healthy dogs and those fitting the criteria for systemic inflammatory response syndrome and to compare these values to commonly measured B‐vitamins.

Methods

Study dogs were classified into non‐infectious systemic inflammatory response syndrome or sepsis groups and blood was drawn on Day 1 of the patient's hospitalisation for measurement of serum homocysteine, folate and cobalamin concentrations. Homocysteine concentration was measured in 51 clinically healthy dogs to serve as the control group.

Results

A statistically significant difference was found between the homocysteine concentrations of the healthy group when compared to non‐infectious systemic inflammatory response syndrome and sepsis groups. Homocysteine values were not correlated with folate, cobalamin or APPLEfast severity scores. Homocysteine concentrations were significantly lower in sick dogs when compared to the control group, which is dissimilar to the human population.

Clinical Significance

The clinical significance of homocysteine changes in critically ill dogs is currently unknown.
TheLeporidDatum: a lateMiocene biotic marker
Authors: Flynn Lawrence J. , Winkler Alisa J. , Erbaeva Margarita , Alexeeva Nadia , Anders Ulrike , Angelone Chiara , Čermák Stanislav , Fladerer Florian A. , Kraatz Brian , Ruedas Luis A. , Ruf Irina , Tomida Yukimitsu , Veitschegger Kristof , Zhang Zhaoqun
Published: November 2013

AlthoughLagomorpha (rabbits, hares and pikas) have a long evolutionary history inEurasia andAfrica, including primitive genera ofEurasia historically considered assignable at the family level toLeporidae, the predecessors of modern rabbits were absent throughout this vast region for most of theMiocene until late in that epoch. During the early and middleMiocene, crown groupLeporidae differentiated inNorthAmerica, then dispersed to northernAsia in the lateMiocene around 8 Ma(million years before present) and afterward. They then spread widely and apparently rapidly throughoutEurasia, reachingSouthAsia by 7.4 Maand penetratingAfrica about 7 Ma.

The apparently abrupt introduction ofLeporidae is a striking lateMiocene event that we call theLeporidDatum. Perceived in terms of biochrons, theLeporidDatum includes localities inEurope and westernAsia of lateMN11 (MammifèresNéogènes system) age and younger, and precedes by less than one million years theBahean‐Baodean land mammal age boundary inChina.

The lateMiocene spread ofLeporidae throughoutEurasia was a successful invasion in terms of the numerous occurrences and abundant fossils preserved. Where dating is sufficiently robust, theLeporidDatum is lateMiocene, nowhere certainly more than ∼8 Ma.

In contrast to this sudden and widespread invasion, rare older finds suggest two possible refinements to this scenario: stem lagomorphs close to modernLeporidae may have lingered into the middleMiocene ofEurasia, or an independent, unsuccessful leporid invasion fromNorthAmerica may have preceded the 8 Madatum.

TheLeporidDatum marks an important palaeoecological event for theOldWorld and complements the significance of molecular dates for origins of modern genera.
A complex regulatory network controlling intrinsic multidrug resistance in Mycobacterium smegmatis
Authors: Bowman Joshua , Ghosh Pallavi
Published: November 2013

Mycobacteria are intrinsically resistant to a variety of stresses including many antibiotics. Although a number of pathways have been described to account for the observed resistances, the mechanisms that control the expression of genes required in these processes remain poorly defined. Here we report the role of a predicted anti‐sigma factor, MSMEG_6129 and a predicted eukaryotic like serine/threonine protein kinase, MSMEG_5437, in the intrinsic resistance of Mycobacterium smegmatis to a variety of stresses including the genotoxic agent mitomycin C, hydrogen peroxide and at least four different antibiotics – isoniazid, chloramphenicol, erythromycin and tetracycline. We show that MSMEG_5437 influences the phosphorylation state of MSMEG_6129. Further, MSMEG_6129 controls the expression of a plethora of genes including efflux pumps, ABC transporters, catalases and transcription factors, either directly or via regulators like WhiB7, which account for the observed multi‐drug resistance phenotypes. MSMEG_6129 in turn phosphorylates a contiguously located putative anti‐anti‐sigma factor, MSMEG_6127. We therefore propose that MSMEG_5437, MSMEG_6129 and MSMEG_6127 are components of a master regulatory network, upstream of whiB7, that controls the activity of one or more of the 28 sigma factors in M. smegmatis. Together, this network controls the expression of a regulon required for resistance to several unrelated antibiotics.
Stem girdling affects the quantity of CO2 transported in xylem as well as CO2 efflux from soil
Authors: Bloemen Jasper , Agneessens Laura , Van Meulebroek Lieven , Aubrey Doug P. , McGuire Mary Anne , Teskey Robert O. , Steppe Kathy
Published: November 2013

There is recent clear evidence that an important fraction of root‐respired CO2 is transported upward in the transpiration stream in tree stems rather than fluxing to the soil. In this study, we aimed to quantify the contribution of root‐respired CO2 to both soil CO2 efflux and xylem CO2 transport by manipulating the autotrophic component of belowground respiration.

We compared soil CO2 efflux and the flux of root‐respired CO2 transported in the transpiration stream in girdled and nongirdled 9‐yr‐old oak trees (Quercus robur) to assess the impact of a change in the autotrophic component of belowground respiration on both CO2 fluxes.

Stem girdling decreased xylem CO2 concentration, indicating that belowground respiration contributes to the aboveground transport of internal CO2. Girdling also decreased soil CO2 efflux.

These results confirmed that root respiration contributes to xylem CO2 transport and that failure to account for this flux results in inaccurate estimates of belowground respiration when efflux‐based methods are used. This research adds to the growing body of evidence that efflux‐based measurements of belowground respiration underestimate autotrophic contributions.
Travertine: Distinctive depositional fabrics of carbonates from thermal spring systems
Authors: Gandin Anna , Capezzuoli Enrico
Published: November 2013

The terrestrial limestones forming at the emergence of thermal springs show a variety of unusual depositional facies. The specific lithological and petrological features of these deposits have few counterparts in the marine, and continental, karst‐related carbonates, but they are typical of the epigean limestone that has been quarried since antiquity in the surroundings of Tivoli (Rome) under the name of travertine, where it is still forming in hydro‐geothermal fields linked to extensional tectonics. The physicochemical, hydrodynamic and geological conditions specific to the Tivoli thermal spring system imply hypersaturated alkaline–sulphate, warm to hot waters, upwelling from springs fed through open fractures/faults in extensional and/or volcanic regimes. These features, together with the hydrodynamic behaviour of the water flows running from the vents, control the petrogenetic features of the travertine, a well‐bedded, mostly finely laminated, porous but quite compact limestone. The results of a detailed comparative petrological analysis carried out on the lithofacies of travertine limestones, and of those observed during formation within numerous active thermal spring fields, provide the elements required for an exhaustive textural classification of the travertine lithofacies, which has not yet been described systematically. According to the genetic processes and fabrics, the thermal deposits that originate from such hypersaturated alkaline–sulphate, warm to hot waters, can be subdivided into: abiotic crystalline crusts, microbially mediated crusts (microbialites) and granular deposits mostly represented by small accumulations of lime‐mudstone. Some of the granular deposits and the microbialites are only partially comparable with analogous sediments forming on tidal flats/sabkhas or other continental sites; however, the facies association of crystalline crusts and laminar curled microbialites has no counterpart in the marine realm. The widespread presence of thermophile bacteria and sulphobacteria, and the general absence of autochthonous eukaryote organisms, unable to live in poisonous sulphate waters, are also undeniable evidence of their thermal origin.
AtRH57, a DEAD‐box RNA helicase, is involved in feedback inhibition of glucose‐mediated abscisic acid accumulation during seedling development and additively affects pre‐ribosomal RNA processing with high glucose
Authors: Hsu Yi‐Feng , Chen Yun‐Chu , Hsiao Yu‐Chun , Wang Bing‐Jyun , Lin Shih‐Yun , Cheng Wan‐Hsing , Jauh Guang‐Yuh , Harada John J. , Wang Co‐Shine
Published: November 2013

The Arabidopsis thaliana T‐DNA insertion mutant rh57‐1 exhibited hypersensitivity to glucose (Glc) and abscisic acid (ABA). The other two rh57 mutants also showed Glc hypersensitivity similar to rh57‐1, strongly suggesting that the Glc‐hypersensitive feature of these mutants results from mutation of AtRH57. rh57‐1 and rh57‐3 displayed severely impaired seedling growth when grown in Glc concentrations higher than 3%. The gene, AtRH57 (At3g09720), was expressed in all Arabidopsis organs and its transcript was significantly induced by ABA, high Glc and salt. The new AtRH57 belongs to class II DEAD‐box RNA helicase gene family. Transient expression of AtRH57‐EGFP (enhanced green fluorescent protein) in onion cells indicated that AtRH57 was localized in the nucleus and nucleolus. Purified AtRH57‐His protein was shown to unwind double‐stranded RNA independent of ATP in vitro. The ABA biosynthesis inhibitor fluridone profoundly redeemed seedling growth arrest mediated by sugar. rh57‐1 showed increased ABA levels when exposed to high Glc. Quantitative real time polymerase chain reaction analysis showed that AtRH57 acts in a signaling network downstream of HXK1. A feedback inhibition of ABA accumulation mediated by AtRH57 exists within the sugar‐mediated ABA signaling. AtRH57 mutation and high Glc conditions additively caused a severe defect in small ribosomal subunit formation. The accumulation of abnormal pre‐rRNA and resistance to protein synthesis‐related antibiotics were observed in rh57 mutants and in the wild‐type Col‐0 under high Glc conditions. These results suggested that AtRH57 plays an important role in rRNA biogenesis in Arabidopsis and participates in response to sugar involving Glc‐ and ABA signaling during germination and seedling growth.
Recognize and Manipulate Pressure to Influence How Components Will Self-Assemble
Authors: Bayles Brenda K. Krkosska
Published: November 2013

How can we engineer components to assemble into complex structures in a reliable manner? Experimental methods rely on interactions such as surface properties, magnetic dipoles, charge, and polarizability. Here pressure is shown to have the power to hold a system together, or to take it apart. Specific diagrams give visual clues to the nature of the pressure that is present. The ability to identify the properties of pressure will allow researchers to manipulate pressure’s power to their advantage. DNA base pairing, polynucleotide chain properties, and an enzyme-catalyzed reaction are used as examples of self-assembling structures conforming to laws of pressure.
Spatiotemporal Temperature in a Tumor During Nanorod Assisted Thermal Therapy
Authors: Soni Sanjeev , Tyagi Himanshu , Taylor Robert A. , Kumar Amod
Published: November 2013

Gold nanoparticles, especially nanorods, are emerging as a promising future material to achieve targeted thermal treatment for cancer. The treatment involves nanoparticle-radiation interaction phenomenon to generate the heat confined to a specific region. Obtaining effective treatments requires a more detailed theoretical understanding of this phenomenon. This study evaluates the temperature field in a tumor tissue embedded with gold nanorods, considering a two dimensional domain representing a skin tumor, irradiated with near infrared radiation. The results indicate that it is possible to localize the heat damage to the tumor region while surrounding healthy tissues are spared. The developed numerical model predicts the temperature through various input of the involved process parameters like size, concentration and irradiation intensity.
Nature Nanocomposite Versus Man-Made Nanocomposites: Studies of Nanoscale Structural, Chemical and Mechanical Hierarchy of a Fish Scale in Contrast With Man-Made Polymer Nanocomposites
Authors: Devaprakasam D.
Published: November 2013

Hierarchical designs of biological structures have remarkable physical, chemical mechanical and biological properties and functionalities over the wide range of length scales [1–4]. Man-made nanocomposites have dramatic improvement of the structural and mechanical properties but however they have very limited hierarchy [5]. Fish scales are bone-like tissues, which form a protective layer on the body of the fish and enable the fish to swim efficiently. Bones and bone-like parts in living organism are formed as tissues by self-assembly of bio-minerals and protein matrix. These tissues are bio-nanocomposites and have hierarchical structure ranging from nanoscale to macroscale [2–4]. Bio-hierarchy contains different bio-macromolecules, bio-minerals, interfacial bonds and porosity which result in gradient mechanical properties at multiple length scales [1–6]. Fish scale consists of inorganic bio-minerals and organic collagens [3,4]. Multilevel hierarchy influences elasticity, hardness and fracture toughness of fish scale. They have additional functions related to movement including reduction or increase of drag [7] and rapid manoeuvre while they are hunting or avoiding predators. In this article we report comparison studies of hierarchical nanocomposite of sardina pilchardus(sp) fish scale and man-made SiO2 nanoparticles filled nanocomposites.
A Multiscale Pressure-Volume Model of Celebrospinal Fluid Dynamics: Application to Hydrocephalus
Authors: Kauffman Justin , Drapaca Corina S.
Published: November 2013

Hydrocephalus is a brain disease characterized by abnormalities in the cerebrospinal fluid (CSF) circulation. The treatment is surgical in nature and continues to suffer of poor outcomes. The first mathematical model for studying the CSF pressure-volume relationship in hydrocephalus was proposed by Marmarou in the 1970s. However, the model fails to fully capture the complex CSF dynamics controlled by CSF-brain tissue interactions. In this paper we use fractional calculus to introduce multiscaling effects in Marmarou’s model. We solve our fractional order non-linear differential equation analytically using a modified Adomian decomposition method.
Carbon Nanobrushes Embedded Within Hydrogel Composites for Tissue Engineering
Authors: Marks William H. , Yang Sze C. , Dombi George W. , Bhatia Sujata K.
Published: November 2013

The objective of this work is to study the effect of carbon nanobrushes embedded within hydrogel composites on tissue engineering. The carbon nanobrushes, providing electrical conductivity to the hydrogels, influence the growth and proliferation of clinically relevant cell lines within the hydrogel composite. The composite is comprised of carbon nanobrushes embedded in a biocompatible poloxamer gel. This work assesses the ability of such composite gels to support the growth of tissue by studying fibroblasts and myoctes, which serve as indicators on the feasibility of this platform eventually serving as a matrix to stimulate wound closure and repair injured tissue. In such a model, fibroblasts and myocytes are seeded separately on the composite hydrogel and bathed in culture medium. The experimental model assesses the ability of fibroblasts and myocytes to grow into and adhere to the gel containing carbon nanobrushes. The work demonstrates that carbon nanobrushes can be dispersed within poloxamer gels, and that fibroblasts and myoctyes can proliferate within a poloxamer gel containing homogenously dispersed carbon nanobrushes. The work also examines the role of the carbon nanobrushes in altering the physical properties of the hydrogel composite. This work has relevance for tissue engineering and tissue regeneration in clinical medicine, with a focus on utilizing biomimetic and bioinspired materials, like the carbon nanobrushes, to enhance growth capabilities.
Effects of Freezing on Collagen Nanoscale Structure in Engineered Tissues
Authors: Ozcelikkale Altug , Li Yan , Xu Xianfan , Han Bumsoo
Published: November 2013

The present study aims to systematically investigate the freezing-induced changes that occur at multiple levels of organization of collagen nanostructure in the engineered tissues (ET). Collagen is a major constituent of the extracellular matrix (ECM) of biological tissues, and is also used for scaffold of engineered tissues and biomaterials [1, 2]. Given its abundance and widespread physiological function in vivo, a proper understanding of the relationships between the collagen’s structure, properties, and function is essential for the improvement of current tissue cryopreservation protocols that suffer from highly variable and tissue specific outcomes [3, 4].
Modeling and Simulation of Hydrodynamic Interaction of DNA in a Micro-Fluidic Channel
Authors: Raghavan Sunitha , Maahapatra D. Roy , Samanta Arnab
Published: November 2013

The motion of DNA (in the bulk solution) and the non-Newtonian effective fluid behavior are considered separately and self-consistently with the fluid motion satisfying the no-slip boundary condition on the surface of the confining geometry in the presence of channel pressure gradients. A different approach has been developed to model DNA in the micro-channel. In this study the DNA is assumed as an elastic chain with its characteristic Young’s modulus, Poisson’s ratio and density. The force which results from the fluid dynamic pressure, viscous forces and electromotive forces is applied to the elastic chain in a coupled manner. The velocity fields in the micro-channel are influenced by the transport properties. Simulations are carried out for the DNAs attached to the micro-fluidic wall. Numerical solutions based on a coupled multiphysics finite element scheme are presented. The modeling scheme is derived based on mass conservation including biomolecular mass, momentum balance including stress due to Coulomb force field and DNA-fluid interaction, and charge transport associated to DNA and other ionic complexes in the fluid. Variation in the velocity field for the non-Newtonian flow and the deformation of the DNA strand which results from the fluid-structure interaction are first studied considering a single DNA strand. Motion of the effective center of mass is analyzed considering various straight and coil geometries. Effects of DNA statistical parameters (geometry and spatial distribution of DNAs along the channel) on the effective flow behavior are analyzed. In particular, the dynamics of different DNA physical properties such as radius of gyration, end-to-end length etc. which are obtained from various different models (Kratky-Porod, Gaussian bead-spring etc.) are correlated to the nature of interaction and physical properties under the same background fluid environment.
Critical Long Bone Defect Treated by Magnetic Scaffolds and Fixed by Permanent Magnets
Authors: Russo Alessandro , Panseri Silvia , Shelyakova Tatiana , Sandri Monica , Dionigi Chiara , Ortolani Alessandro , Meikle Steve , Lacey Joe , Tampieri Anna , Dediu Valentin , Santin Matteo , Marcacci Maurilio
Published: November 2013

Diaphyseal bone defect represents a significant problem for orthopaedic surgeons and patients. In order to improve and fasten bone regenerating process we implanted HA biodegradable magnetized scaffolds in a large animal model critical bone defect.

A critical long bone defect was created in 6 sheep metatarsus diaphysis; then we implanted a novel porous ceramic composite scaffold (20.0 mm in length; 6.00 mm inner diameter and 17.00 mm outer diameter), made of Hydroxyapatite that incorporates magnetite (HA/Mgn 90/10), proximally fixated by two small cylindrical permanent parylene coated NdFeB magnets (one 6.00 mm diameter magnetic rod firmly incorporated into the scaffold and one 8.00 mm diameter magnetic rods fitted into proximal medullary canal, both 10.00 mm long); to give stability to the complex bone-scaffold-bone, screws and plate was used as a bridge. Scaffolds biocompatibility was previously assessed in vitro using human osteoblast-like cells. Magnetic forces through scaffold were calculated by finite element software (COMSOL Multiphysics, AC/DC Model).

One week after surgery, magnetic nanoparticles functionalized with vascular endothelial growth factor (VEGF) were injected at the mid portion of the scaffold using a cutaneous marker positioned during surgery as reference point. After sixteen weeks, sheep were sacrificed to analyze metatarsi. Macroscopical, radiological and microCT examinations were performed.

Macroscopical examination shows bone tissue formation inside scaffold pores and with complete coverage of scaffolds, in particular at magnetized bone-scaffold interface. X-rays show a good integration of the scaffold with a good healing process of critical bone defect, and without scaffolds mobilization. These datas were confirmed by the microCT that shown new formation of bone inside the scaffolds, in particular at magnetized bone-scaffold interface.

These preliminary results lead our research to exploiting magnetic forces to stimulate bone formation, as attested in both in vitro and in vivo models and to improve fixation at bone scaffold interface, as calculated by finite element software, and moreover to guide targeted drug delivery without functionalized magnetic nanoparticles dissemination in all body.

Histological analysis will be performed to confirm and quantify bone tissue regeneration at both interfaces.
In Vivo Biomarker Capture via the Skin Using Surface-Modified Microprojection Arrays
Authors: Corrie Simon R. , Coffey Jacob W. , Kendall Mark A. F.
Published: November 2013

Whilst blood is the sample most often collected for diagnostic purposes, testing is complicated by the need to purify or concentrate biomarkers prior to detection. While needle/syringe or lancet technology is most often used for bulk sample collection, devices have not yet been developed that selectively capture biomarkers of interest in vivo, simplifying downstream detection requirements. Our group developed the Micropatch Array — a device comprising an array of microprojections which breach the outer layers of the skin to selectively capture biomarkers from the dermis. In this presentation we will describe our emerging data focused on the mechanisms of biomarker capture in vivo, and our investigations into improving the capture efficiency of the devices for important biomarkers.
Advanced Biomimetic Nanodevice Using Nanotechnology Addressable Lipid Rafts Nanoarrays Toward Advanced Nanomaterials
Authors: Lee HeaYeon , Lee JuKyung
Published: November 2013

In recent years, a new paradigm of nanobiomedical devices combining miniaturization and integration has been exploited in areas such as combinational chemistry, biotechnology, engineering, proteomics and clinical diagnostics. One of the critical issues in the development of nanobiomedical system is how to differentiate signal-to-noise ratio per very small amount of signal. Biocompatible integrated nanopattern requires the fabrication of appropriately designed nanomatrix for high sensitivity homogenous assays, which are capable of ultimately mimic the physiological environment. We reported the nanomatrix geometry of a well-oriented nanowell array derived from nanofabrication technology which can easily be employed for digital detection with a high S/N ratio, miniaturization, integrated assays and single molecule analysis. In this present, we describe a nano(submicro) array of tethered lipid bilayer raft membranes comprising a biosensing platform.
Applying distance sampling to fin whale calls recorded by single seismic instruments in the northeast Atlantic
Authors: Harris Danielle , Matias Luis , Thomas Len , Harwood John , Geissler Wolfram H.
Published: November 2013

Automated methods were developed to detect fin whale calls recorded by an array of ocean bottom seismometers (OBSs) deployed off the Portuguese coast between 2007 and 2008. Using recordings collected on a single day in January 2008, a standard seismological method for estimating earthquake location from single instruments, the three-component analysis, was used to estimate the relative azimuth, incidence angle, and horizontal range between each OBS and detected calls. A validation study using airgun shots, performed prior to the call analysis, indicated that the accuracy of the three-component analysis was satisfactory for this preliminary study. Point transect sampling using cue counts, a form of distance sampling, was then used to estimate the average probability of detecting a call via the array during the chosen day. This is a key step to estimating density or abundance of animals using passive acoustic data. The average probability of detection was estimated to be 0.313 (standard error: 0.033). However, fin whale density could not be estimated due to a lack of an appropriate estimate of cue (i.e., vocalization) rate. This study demonstrates the potential for using a sparse array of widely spaced, independently operating acoustic sensors, such as OBSs, for estimating cetacean density.
Measurement of complex acoustic intensity in an acoustic waveguide
Authors: Duan Wenbo , Kirby Ray , Prisutova Jevgenija , Horoshenkov Kirill V.
Published: November 2013

Acoustic intensity is normally treated as a real quantity, but in recent years, many articles have appeared in which intensity is treated as a complex quantity where the real (active) part is related to local mean energy flow and the imaginary (reactive) part to local oscillatory transport of energy. This offers the potential to recover additional information about a sound field and then to relate this to the properties of the sound source and the environment that surrounds it. However, this approach is applicable only to multi-modal sound fields, which places significant demands on the accuracy of the intensity measurements. Accordingly, this article investigates the accuracy of complex intensity measurements obtained using a tri-axial Microflown intensity probe by comparing measurement and prediction for sound propagation in an open flanged pipe. Under plane wave conditions, comparison between prediction and experiment reveals good agreement, but when a higher order mode is present, the reactive intensity field becomes complicated and agreement is less successful. It is concluded that the potential application of complex intensity as a diagnostic tool is limited by difficulties in measuring reactive intensity in complex sound fields when using current state of the art acoustic instrumentation.
Finite difference time domain simulation for the brass instrument bore
Authors: Bilbao Stefan , Chick John
Published: November 2013

In this article, interleaved finite difference time domain methods are developed for the purpose of simulating the dynamics of the acoustic bore, using, as a starting point, an impedance formulation of wave propagation in an acoustic tube; attention is focused here on modeling of viscothermal and radiation losses in the time domain. In particular, in contrast to other methods, the bore, including the mouth-piece and bell, is treated as a unit, and is not subdivided into smaller units such as cylindrical or conical segments. Numerical simulations of input impedances are then compared with measurement for a variety of brass instruments.
Native language affects rhythmic grouping of speech
Authors: Bhatara Anjali , Boll-Avetisyan Natalie , Unger Annika , Nazzi Thierry , Höhle Barbara
Published: November 2013

Perceptual attunement to one's native language results in language-specific processing of speech sounds. This includes stress cues, instantiated by differences in intensity, pitch, and duration. The present study investigates the effects of linguistic experience on the perception of these cues by studying the Iambic–Trochaic Law (ITL), which states that listeners group sounds trochaically (strong-weak) if the sounds vary in loudness or pitch and iambically (weak-strong) if they vary in duration. Participants were native listeners either of French or German; this comparison was chosen because French adults have been shown to be less sensitive than speakers of German and other languages to word-level stress, which is communicated by variation in cues such as intensity, fundamental frequency (F0), or duration. In experiment 1, participants listened to sequences of co-articulated syllables varying in either intensity or duration. The German participants were more consistent in their grouping than the French for both cues. Experiment 2 was identical to experiment 1 except that intensity variation was replaced by pitch variation. German participants again showed more consistency for both cues, and French participants showed especially inconsistent grouping for the pitch-varied sequences. These experiments show that the perception of linguistic rhythm is strongly influenced by linguistic experience.
Integrated tuned vibration absorbers: A theoretical study
Authors: Gardonio Paolo , Zilletti Michele
Published: November 2013

This article presents a simulation study on two integrated tuned vibration absorbers (TVAs) designed to control the global flexural vibration of lightly damped thin structures subject to broad frequency band disturbances. The first one consists of a single axial switching TVA composed by a seismic mass mounted on variable axial spring and damper elements so that the characteristic damping and natural frequency of the absorber can be switched iteratively to control the resonant response of three flexural modes of the hosting structure. The second one consists of a single three-axes TVA composed by a seismic mass mounted on axial and rotational springs and dampers, which are arranged in such a way that the suspended mass is characterized by uncoupled heave and pitch-rolling vibrations. In this case the three damping and natural frequency parameters of the absorber are tuned separately to control three flexural modes of the hosting structure. The simulation study shows that the proposed single-unit absorbers produce, respectively, 5.3 and 8.7 dB reductions of the global flexural vibration of a rectangular plate between 20 and 120 Hz.
An inverse method for estimating the electromechanical parameters of moving-coil loudspeakers
Authors: Tsai Yu-Ting , Wang Chi-Chang , Huang Jin H.
Published: November 2013

This article presents an inverse method for estimating the electromechanical parameters of a moving-coil loudspeaker with or without the eddy current and suspension creep effects. With known voice-coil displacement, voice-coil current, and stimulus signal as inputs, four calculation procedures for the direct problem, adjoint problem, sensitivity problem, and conjugate gradient method are involved in inversely solving the unknown electromechanical parameters. The proposed method features high efficiency in solving the direct problem through a hybrid spline difference method. It requires a small number of iterations for the computational algorithm, while offering excellent accuracy in parameter estimations. Analysis results demonstrate small differences between the estimated and measured electromechanical parameters under a variety of stimulus signals, excitation times, and initial guesses. The results are also confirmed by experimental measurements. These results indicate that the proposed method has a strong potential for estimating the electromechanical parameters of moving-coil loudspeakers.
Developmental and gender-related trends of intra-talker variability in consonant production
Authors: Romeo Rachel , Hazan Valerie , Pettinato Michèle
Published: November 2013

This study investigates the effect of age and gender on the internal structure, cross-category distance, and discriminability of phonemic categories for two contrasts varying in fricative place of articulation (/s/-/∫/) and stop voicing (/b/-/p/) in word-initial tokens spoken by adults and normally developing children aged 9–14 yr. Vast between- and within-talker variability was observed with 16% of speakers exhibiting some degree of overlap between phonemic categories—a possible contribution to the range of talker intelligibility found in the literature. Females of all ages produced farther and thus more discriminable categories than males, although gender-marking for fricative between-category distance did not emerge until approximately 11 yr of age. Children produced farther yet also much more dispersed categories than adults with increasing discriminability with age, such that by age 13, children's categories were no less discriminable than those of adults. However, children's ages did not predict category distance or dispersion, indicating that convergence on adult-like category structure must occur later in adolescence.
Analytical and numerical modeling of an axisymmetrical electrostatic transducer with interior geometrical discontinuity
Authors: Honzík Petr , Podkovskiy Alexey , Durand Stéphane , Joly Nicolas , Bruneau Michel
Published: November 2013

The main purpose of the paper is to contribute at presenting an analytical and a numerical modeling which would be relevant for interpreting the couplings between a circular membrane, a peripheral cavity having the same external radius as the membrane, and a thin air gap (with a geometrical discontinuity between them), and then to characterize small scale electrostatic receivers and to propose procedures that could be suitable for fitting adjustable parameters to achieve optimal behavior in terms of sensitivity and bandwidth expected. Therefore, comparison between these theoretical methods and characterization of several shapes is dealt with, which show that the models would be appropriate to address the design of such transducers.