bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancing the Equating of Item Difficulty Metrics: Estimation of Reference Distribution
Authors: Ali Usama S. , Walker Michael E. 
Published: May 2014

AbstractTwo methods are currently in use at Educational Testing Service (ETS) for equating observed item difficulty statistics. The first method involves the linear equating of item statistics in an observed sample to reference statistics on the same items. The second method, or the item response curve (IRC) method, involves the summation of conditional observed item statistics across the reference population total score frequencies. This article introduces a quick and effective method for obtaining the reference distribution for the transition from the linear equating method to the IRC method without recalculating all the item difficulties. More specifically, a mathematical formula is derived to estimate the score distribution of a reference group that maintains the current item difficulty scale. Future research is needed to compare the performance of the two approaches.
Raman spectroscopy as an analytical tool for analysis of vegetable and essential oils
Authors: Vargas Jentzsch Paul , Ciobotă Valerian 
Published: May 2014

ABSTRACTVegetable and essential oils are very important raw materials in the food, cosmetic and/or pharmaceutical industries. Vegetable oils are composed fundamentally of triglycerides (esters derived from glycerol and fatty acids). Triglycerides have different chemical characteristics depending on the seed or fruit from which they are extracted, with those containing unsaturated fatty acids being the most appreciated. Essential oils are composed of volatile compounds extracted from aromatic plants. Some of these volatile compounds are highly appreciated by the cosmetic and pharmaceutical industries. The economic relevance of vegetable and essential oils implies the need of appropriate analytical techniques to evaluate their quality. Raman spectroscopy is a remarkable non‐destructive and versatile analytical technique that provides a fast identification of vegetable and essential oils. In this work, measurements were performed on 19 vegetable oils and 9 essential oils using a portable Raman spectrometer. The most important bands observed in the Raman spectra are discussed. It is difficult to distinguish vegetable oils from each other only by visual inspection of their spectra, because the spectra show important similarities. However, identification can be performed successfully using chemometric methods. On the other hand, essential oils can be distinguished by visual inspection, because their spectra show sharp characteristic bands. This work may serve as a basis for future works using Raman spectroscopy not only to confirm the authenticity of oils and the presence/absence of certain compounds in essential oils, but also to trace back their origin and the extraction methods used during the production process. Copyright © 2014 John Wiley & Sons, Ltd.
Brainstem abnormalities in attention deficit hyperactivity disorder support high accuracy individual diagnostic classification
Authors: Johnston Blair A. , Mwangi Benson , Matthews Keith , Coghill David , Konrad Kerstin , Steele J. Douglas 
Published: May 2014

AbstractDespite extensive research, psychiatry remains an essentially clinical and, therefore, subjective clinical discipline, with no objective biomarkers to guide clinical practice and research. Development of psychiatric biomarkers is consequently important. A promising approach involves the use of machine learning with neuroimaging, to make predictions of diagnosis and treatment response for individual patients. Herein, we describe predictions of attention deficit hyperactivity disorder (ADHD) diagnosis using structural T1 weighted brain scans obtained from 34 young males with ADHD and 34 controls and a support vector machine. We report 93% accuracy of individual subject diagnostic prediction. Importantly, automated selection of brain regions supporting prediction was used. High accuracy prediction was supported by a region of reduced white matter in the brainstem, associated with a pons volumetric reduction in ADHD, adjacent to the noradrenergic locus coeruleus and dopaminergic ventral tegmental area nuclei. Medications used to treat ADHD modify dopaminergic and noradrenergic function. The white matter brainstem finding raises the possibility of “catecholamine disconnection or dysregulation” contributing to the ADHD syndrome, ameliorated by medication. Hum Brain Mapp 35:5179–5189, 2014. © 2014 Wiley Periodicals, Inc.
In vitrobiological response of micro‐ and nano‐sized monosodium titanates and titanate–metal compounds
Authors: Drury Jeanie L. , Jang Yoonji , Taylor‐Pashow Kathryn M. L. , Elvington Mark , Hobbs David T. , Wataha John C. 
Published: May 2014

AbstractPrevious studies report that microsized monosodium titanates (MSTs) deliver metal ions and species to mammalian cells and bacteria with cell‐specific and metal‐specific effects. In this study, we explored the use of MST and a new synthesized nanosized monosodium titanate (nMST) to deliver gold(III),cisplatin, or platinum(IV) to two human cell lines with different population doubling times,in vitro. The effect was measured using a fluorescent mitochondrial activity assay (CellTiter‐Blue®Assay). This fluorescence assay was implemented to mitigate optical density measurement errors owing to particulate titanate interference and allowed for the studies to be extended to higher titanate concentrations than previously possible. Overall, native MST significantly (p < 0.05) decreased mitochondrial activity of both cell types by 50% at concentrations of >50 mg/L. Native nMST significantly suppressed the rapidly dividing cell line (by 50%) over untreated cultures, but had no effect on the more slowly dividing cells. For both cell types, increased titanate concentrations resulted in increased effects from delivered metals. However, there was no difference in the effect of metal delivered from micro‐ versus nano‐sized MST. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 254–260, 2015.
Potent antimicrobial activity of bone cement encapsulating silver nanoparticles capped with oleic acid
Authors: Prokopovich Polina , Köbrick Mathias , Brousseau Emmanuel , Perni Stefano 
Published: May 2014

AbstractBone cement is widely used in surgical treatments for the fixation for orthopaedic devices. Subsequently, 2–3% of patients undergoing these procedures develop infections that are both a major health risk for patients and a cost for the health service providers; this is also aggravated by the fact that antibiotics are losing efficacy because of the rising resistance of microorganisms to these substances. In this study, oleic acid capped silver nanoparticles (NP) were encapsulated into Poly(methyl methacrylate) (PMMA)‐based bone cement samples at various ratios. Antimicrobial activity against Methicillin Resistant Staphylococcus aureus, S. aureus, Staphylococcus epidermidis, Acinetobacter baumannii was exhibited at NP concentrations as low as 0.05% (w/w). Furthermore, the mechanical properties and cytotoxicity of the bone cement containing these NP were assessed to guarantee that such material is safe to be used in orthopaedic surgical practice. © 2014 The Authors. Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 273–281, 2015.
Experimental and numerical evaluation of drug release from nanofiber mats to brain tissue
Authors: Nakielski Paweł , Kowalczyk Tomasz , Zembrzycki Krzysztof , Kowalewski Tomasz A. 
Published: May 2014

AbstractDrug delivery systems based on nanofibrous mats appear to be a promising healing practice for preventing brain neurodegeneration after surgery. One of the problems encountered during planning and constructing optimal delivery system based on nanofibrous mats is the estimation of parameters crucial for predicting drug release dynamics. This study describes our experimental setup allowing for spatial and temporary evaluation of drug release from nanofibrous polymers to obtain data necessary to validate appropriate numerical models. We applied laser light sheet method to illuminate released fluorescent drug analog and CCD camera for imaging selected cross‐section of the investigated volume. Transparent hydrogel was used as a brain tissue phantom. The proposed setup allows for continuous observation of drug analog (fluorescent dye) diffusion for time span of several weeks. Images captured at selected time intervals were processed to determine concentration profiles and drug release kinetics. We used presented method to evaluate drug release from several polymers to validate numerical model used for optimizing nanofiber system for neuroprotective dressing. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 282–291, 2015.
Downregulation of Homeodomain‐Interacting Protein Kinase‐2 Contributes to Bladder Cancer Metastasis by Regulating Wnt Signaling
Authors: Tan Mingyue , Gong Hua , Zeng Yigang , Tao Le , Wang Jun , Jiang Juntao , Xu Dongliang , Bao Erdun , Qiu Jianxin , Liu Zhihong 
Published: May 2014

ABSTRACTHomeodomain‐interacting protein kinase‐2 (Hipk2) has been shown to have important regulatory roles in cancer biology, such as cancer cell proliferation, cell cycle, and cell invasion. However, the contributions of Hipk2 to bladder cancer metastasis remain largely unknown. In the current study, we assayed the expression level of Hipk2 in bladder cancer tissues by real‐time PCR, and defined its biological functions. We found that Hipk2 levels were downregulated in most bladder cancer tissues compared with adjacent normal tissues, and Hipk2 levels were remarkably decreased in metastasized tumor tissues when compared with primary tumors. SiRNA‐mediated Hipk2 silencing increased bladder cancer cell invasion. Hipk2 knockdown resulted in decrease of E‐cadherin expression and increase of N‐cadherin and fibronectin expression, indicated that epithelial‐mesenchymal transition (EMT) was induced. We further demonstrated that Hipk2 knockdown induced Wnt signaling activation and β‐catenin nuclear localization. Finally, we confirmed that Hipk2 inhibition promoted EMT and subsequent cell invasion, at least in part by activating Wnt signaling. These data suggest an important role of Hipk2 in regulating metastasis of bladder cancer and implicate the potential application of Hipk2 in bladder cancer therapy. J. Cell. Biochem. 115: 1762–1767, 2014. © 2014 Wiley Periodicals, Inc.
mTORC1 Is Involved in Hypoxia‐Induced Pulmonary Hypertension Through the Activation of Notch3
Authors: Wang Wang , Liu Jie , Ma Aiping , Miao Ran , Jin Yuling , Zhang Hongbing , Xu Kaifeng , Wang Chen , Wang Jun 
Published: May 2014

AbstractHypoxia‐induced pulmonary hypertension (HPH) is a clinical syndrome associated with high morbidity and mortality. However, the underlying mechanisms remain unclear. Both the mammalian target of rapamycin (mTOR) and the Notch3 signaling pathways have been reported to be involved in HPH; however, it is unknown whether there is a connection between these two signaling pathways in HPH. This study was designed to investigate the relationship between mTOR and Notch3 in HPH. After treatment with 10% O2 for 4 weeks, male C57BL/6 mice developed HPH with gradually increased right ventricular systolic pressure (RVSP), right ventricular hypertrophy index (RVHI), and pulmonary arteriolar remodeling accompanied by the activation of mTOR complex 1 (mTORC1) and Notch3 in the lung tissue and pulmonary arterioles. Pretreatment with the mTORC1 inhibitor rapamycin not only alleviated pulmonary arterial pressure and pulmonary arteriolar remodeling but also suppressed hypoxia‐induced mTORC1 and Notch3 activation. Prophylactic N‐[N‐(3,5‐difluorophenacetyl)‐L‐alanyl]‐S‐phenylglycine t‐butyl ester (DAPT) administration, a Notch signaling inhibitor, protected against the effects of hypoxia. These in vivo data were confirmed by in vitro experiments on human pulmonary arterial smooth muscle cell (PASMC) exposed to 3% O2. Furthermore, overexpression of Notch3 intracellular domain partially abrogated the inhibitory effects of rapamycin on human PASMC proliferation. These data indicate that both mTORC1 and Notch3 signaling are involved in HPH and the downstream effects of mTORC1 activation in HPH are partially dependent on the activation of Notch3 signaling. J. Cell. Physiol. 229: 2117–2125, 2014. © 2014 Wiley Periodicals, Inc.
Gender Differences in the Associations of PTSD Symptom Clusters With Relationship Distress in U.S. Vietnam Veterans and Their Partners
Authors: Renshaw Keith D. , Campbell Sarah B. , Meis Laura , Erbes Christopher 
Published: May 2014

AbstractResearch has consistently linked symptoms of posttraumatic stress disorder (PTSD) with relationship distress in combat veterans and their partners. Studies of specific clusters of PTSD symptoms indicate that symptoms of emotional numbing/withdrawal (now referred to as negative alterations in cognition and mood) are more strongly linked with relationship distress than other symptom clusters. These findings, however, are based predominantly on samples of male veterans. Given the increasing numbers of female veterans, research on potential gender differences in these associations is needed. The present study examined gender differences in the multivariate associations of PTSD symptom clusters with relationship distress in 465 opposite‐sex couples (375 with male veterans and 90 with female veterans) from the National Vietnam Veterans Readjustment Study. Comparisons of nested path models revealed that emotional numbing/withdrawal symptoms were associated with relationship distress in both types of couples. The strength of this association, however, was stronger for female veterans (b = .46) and female partners (b = .28), compared to male veterans (b = .38) and male partners (b = .26). Results suggest that couples‐based interventions (e.g., psychoeducation regarding emotional numbing symptoms as part of PTSD) are particularly important for both female partners of male veterans and female veterans themselves.
Identification of Aurora‐A Inhibitors by Ligand and Structure‐Based Virtual Screening
Authors: Morshed Mohammad Neaz 
Published: May 2014

AbstractAurora kinase A has been identified as one of the most attractive targets for cancer therapy because of its critical role in the regulation of the cell cycle. In order to identify active compounds with structural diversity we performed virtual screening. 3D‐QSAR pharmacophore models were developed and the best model was used as a query for screening the databases. Ligand and structure‐based virtual screening protocol was conducted sequentially by applying the common feature pharmacophore and molecular docking to discover potent Aurora‐A inhibitors. A total of eighty‐eight compounds were selected for the in vitro activities against various human cancer cell lines (DU145 and HT29). Considering the activity data, we have identified seven compounds to be considered for the next step, among which four compounds had high inhibition rate (above 50 %) at 10 µM with GI50 lower than 10 µM. Based on the cell line and enzyme assay (Aurora‐A & B) result, these four compounds were used as template/query molecule for similarity search. The best result was obtained for similarity hit SH3. It had IC50 of 0.578 and 11.77 µM for Aurora‐A and B respectively, which implies 20‐fold selectivity over Aurora‐B. The hits obtained from this screening scheme could be potential drug candidates after further optimization.
Investigating and Predicting how Biology Changes Molecules and Their Properties
Authors: Tyzack Jonathan D. , Glen Robert C. 
Published: May 2014

AbstractMost molecules are transformed and transported by specific metabolising enzymes and transporters resulting in changes in their bioactivities, pharmacokinetics and toxicity profiles. This is a key consideration in the design of drugs. Ideally, when medicines have performed their task, they need to fade away gracefully, and not introduce unexpected or untoward biological effects. Some examples of predictive metabolism, transport and interesting design considerations of drugs are described.
Optimizing perfectly matched layers in discrete contexts
Authors: Modave A. , Delhez E. , Geuzaine C. 
Published: May 2014

SUMMARYPerfectly matched layers (PMLs) are widely used for the numerical simulation of wave‐like problems defined on large or infinite spatial domains. However, for both time‐dependent and time‐harmonic cases, their performance critically depends on the so‐called absorption function. This paper deals with the choice of this function when classical numerical methods are used (based on finite differences, finite volumes, continuous finite elements and discontinuous finite elements). After reviewing the properties of the PMLs at the continuous level, we analyze how they are altered by the different spatial discretizations. In the light of these results, different shapes of absorption function are optimized and compared by means of both one‐dimensional and two‐dimensional representative time‐dependent cases. This study highlights the advantages of the so‐called shifted hyperbolic function, which is efficient in all cases and does not require the tuning of a free parameter, by contrast with the widely used polynomial functions. Copyright © 2014 John Wiley & Sons, Ltd.
Occupation‐based Assessments and Treatments of Trigger Finger: A Survey of Occupational Therapists from Israel and the United States
Authors: Langer Danit , Luria Shai , Maeir Adina , Erez Asnat 
Published: May 2014

AbstractThe purpose of this study was to describe the reported evaluation and treatment methods commonly administered by occupational therapy (OT) specialists in hand therapy for patients with trigger finger (TF).Sixty‐one therapists from Israel and the United States completed an electronic survey.Sixty‐nine per cent of the therapists reported evaluating TF symptoms (body function level) as part of their assessment protocol; however, only 25% reported the use of occupation‐based measures for the assessment of people with TF. All therapists reported using orthoses to treat TF, yet significant differences were found between the groups regarding the frequency of using physical agent modalities, exercise and activity modifications.The results of the study point to the limited use of occupation‐based assessments and to a lack of consensus regarding treatment guidelines for TF. The study is limited by a restricted sample size and a low response rate from US therapists, which warrant caution in generalization of the findings. Further research is needed to study the broad implications of TF in order to inform the assessment of TF in OT and to establish the foundations for future treatment efficacy studies. Copyright © 2014 John Wiley & Sons, Ltd.
The Implications of Monitoring Frequency for Describing Riverine Water Quality Regimes
Authors: Sergeant C. J. , Nagorski S. 
Published: May 2014

AbstractStrategies to characterize water quality vary widely, but regulatory approaches mainly consider single‐value thresholds for individual parameters (e.g. minimum dissolved oxygen concentration). Distributions of parameter values across multiple temporal and spatial scales, commonly referred to as regimes, add greater context and interpretability to point measurements. Although uncommon among monitoring programmes, continuous water quality data collected at high frequency (e.g. hourly) can characterize waterbody health more accurately than infrequent point measurements. We used multivariate analysis to describe water quality regimes based on hourly measurements of dissolved oxygen, pH, specific conductance and water temperature from three divergent stream types in Southeast Alaska national parks. We also assessed whether less frequent measurements drawn from the original hourly data set resulted in similar water quality regime descriptions. The monthly means and standard deviations of the four water quality parameters created ordinations with interpretable, stream‐specific environmental gradients. Procrustean analysis revealed that ordination results were strikingly similar across all temporal monitoring frequencies. Univariate medians and distributions of weekly, twice monthly and monthly measurements were similar across all parameters, but hourly monitoring was necessary to accurately characterize extreme values. These analyses demonstrated the ability of commonly collected water quality parameters to define unique physical–chemical properties across regional stream types and present scientists with common analytical tools to determine appropriate monitoring scales for accurately characterizing water quality regimes. Copyright © 2014 John Wiley & Sons, Ltd.
Merkle tree‐based wormhole attack avoidance mechanism in low power and lossy network based networks
Authors: Idris Khan Faraz , Shon Taeshik , Lee Taekkyeun , Kim Ki‐Hyung 
Published: May 2014

ABSTRACTSmart metering application has received a lot of attention from the research community lately. Usually, low power and lossy network runs on routing protocol for low power and lossy networks protocol, which constructs a directed acyclic graph structure for its normal operation. In this paper, we devise a wormhole attack scenario in such a network. Furthermore, we propose a Merkle tree‐based authentication mechanism, which runs on the notion of constructing a tree of hashed security information. We analyze the approach by formulating the wormhole attack scenario as a graph theoretic problem and show the effectiveness of the proposed Merkle tree‐based approach for authenticating communications. Furthermore, we perform simulations in network simulator 2 to observe the network performance by adopting a Merkle tree‐based approach to prevent from disrupting the links, and we observe better throughput, reduction in jitter, and end‐to‐end delay as compared with scenarios with wormhole attacks and no avoidance mechanism. In the end, we take a step toward optimizing the performance of the mechanism by proposing an effective tree traversal algorithm, which works on the notion of electing nodes as a root in a large scale network from where a Merkle tree will be originated. The mechanism with the traversal algorithm assists in managing the authentication in a huge network, which is broken down into many trees avoiding wormhole attacks in the network. Copyright © 2014 John Wiley & Sons, Ltd.
Printable solar cells
Authors: Ito Seigo 
Published: May 2014

Printable solar cells attract academic and industrial interests because solar cells should be cost‐effective systems and have to be fabricated by non‐vacuum methods such as screen printing, doctor blading, spin coating, spray deposition, and electrochemical deposition. In order to be a cost‐effective solar system, the solar cells neither include expensive (indium) and toxic materials (cadmium and mercury) nor expensive processes such as chemical vapor deposition and sputtering. Similar to printed solar cells, many types of solar cells have been investigated in the past two decades: organic, dye‐sensitized solar cells, Cu(In,Ga)(S,Se)2, Cu2ZnSn(S,Se)4, organic thin‐film photovoltaic cells, and so on. Now, the photoenergy conversion efficiencies of printed solar cells have been improved by more than 10% with the efforts of scientists. In this review, prominent progress has been presented for the future of our society. WIREs Energy Environ 2015, 4:51–73. doi: 10.1002/wene.112This article is categorized under:

Photovoltaics > Science and Materials
Photovoltaics > Economics and Policy