bluuebunny/crossref_metadata_2025_split huggingface dataset:
Systematic evaluation of the biological variance within the Raman based colorectal tissue diagnostics
Authors: Vogler Nadine , Bocklitz Thomas , Subhi Salah Firas , Schmidt Carsten , Bräuer Rolf , Cui Tiantian , Mireskandari Masoud , Greten Florian R. , Schmitt Michael , Stallmach Andreas , Petersen Iver , Popp Jürgen 
Published: December 2015

Being among the most common cancers worldwide screening and early diagnosis of colorectal cancer is of high interest for the health system, the patients and for research. Raman microspectroscopy as a label‐free, non‐invasive and non‐destructive technique is a promising tool for an early diagnosis. However, to ensure a reliable diagnosis specially designed statistical analysis workflows are required. Several statistical approaches have been introduced leading to varying results in the overall accuracy, sensitivity and specificity. In this study a systematic evaluation of different statistical analysis approaches has been performed using a colon cancer mouse model with genotypic identical individuals. Based on the inter‐individual Raman spectral variances a measure for the biological variance can be estimated. By applying a leave‐one‐individual‐out cross‐validation a clinically relevant discrimination of healthy tissue versus adenoma and carcinoma with an accuracy of 95% is shown. Furthermore, the transfer of a model from tissue to biopsy specimen is demonstrated.
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Engineers at Play: Games as Teaching Tools for Undergraduate Engineering Students
Authors: Bodnar Cheryl A. , Anastasio Daniel , Enszer Joshua A. , Burkey Daniel D. 
Published: December 2015

AbstractBackgroundMany students may not respond strongly to instruction that they do not perceive as engaging. One pedagogical approach to help engage students involves the use of games. Educational games can provide students with a motivating and stimulating environment while providing them with immediate feedback to promote learning.PurposeThis systematic review examines research focused on the implementation of games to teach undergraduate engineering students; it summarizes prevailing features and cites examples from a variety of engineering disciplines.Scope/MethodThe systematic review was conducted through a detailed search of Science Direct journals and the Scopus, Web of Science, Compendex/Inspec, and ERIC Education Research Abstract databases using terms pertinent to games in engineering education. A total of 191 papers was included after application of the inclusion/exclusion criteria. After screening those to determine if assessment of student learning outcomes was performed, 62 papers were found suitable for more detailed analysis.ConclusionsResearch on the implementation of games in undergraduate engineering classrooms has shown that, despite diverse forms of assessment applied, there is a general trend that both student learning and attitudes are improved by game‐based activities. However, since only a relatively small subset of the literature demonstrates a systematic, validated approach in assessment, significant opportunities remain for future research.
Preparing Engineers for the Workplace through Service Learning: Perceptions of EPICS Alumni
Authors: Huff James L. , Zoltowski Carla B. , Oakes William C. 
Published: December 2015

AbstractBackgroundService‐learning programs that emphasize engineering design have been posited to bolster the professional preparedness of engineering alumni. However, we know little about how such programs actually prepare engineers for the workplace. Nor does prior literature fully explain how characteristics of these programs affect professional preparation.PurposeThis study investigates how alumni perceive the impact of one service‐learning program, Engineering Projects in Community Service (EPICS), in preparing them for the workplace. We seek to provide empirical and theoretical foundations about how this program affected the alumni's perceptions of how they were prepared for professional practice.Design/MethodThis investigation was an embedded, sequential mixed‐methods study, which began by administering a survey to 523 participants. On the basis of survey responses, we interviewed 27 participants and conducted a thematic analysis of transcripts to describe how participants related their EPICS experiences to the workplace.ResultsThe findings describe how alumni perceived the role of EPICS in preparing them for the workplace. The thematic analysis reveals how alumni perceived the nature of their preparation through three themes: EPICS was a bridge from education to practice, EPICS provided a means for gaining workplace experience, and EPICS developed a variety of professional skills.ConclusionsGrounded in alumni perspectives, this study demonstrates a strong link between participating in service‐learning activities and navigating the complexity of the workplace. Finally, we identify three key characteristics of EPICS that are transferable to other institutions.
Spectral engineering of coupled open‐access microcavities
Authors: Flatten L.C. , Trichet A.A.P. , Smith J.M. 
Published: December 2015

Open‐access microcavities are emerging as a new approach to confine and engineer light at mode volumes down to the λ3 regime. They offer direct access to a highly confined electromagnetic field while maintaining tunability of the system and flexibility for coupling to a range of matter systems. This article presents a study of coupled cavities, for which the substrates are produced using Focused Ion Beam milling. Based on experimental and theoretical investigation the engineering of the coupling between two microcavities with radius of curvature of 6 m is demonstrated. Details are provided by studying the evolution of spectral, spatial and polarisation properties through the transition from isolated to coupled cavities. Normal mode splittings up to 20 meV are observed for total mode volumes around . This work is of importance for future development of lab‐on‐a‐chip sensors and photonic open‐access devices ranging from polariton systems to quantum simulators.
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Aqueous Solutions of Poly[2‐(N‐morpholino)ethyl methacrylate]: Learning about Macromolecular Aggregation Processes from a Peculiar Three‐Step Thermoresponsive Behavior
Authors: Eggers Steffen , Fischer Birgit , Abetz Volker 
Published: December 2015

Aqueous solutions of narrowly distributed poly[2‐(N‐morpholino)ethyl methacrylate], a biocompatible multiple stimuli‐responsive polymer, show a peculiar three‐step aggregation behavior upon heating, an effect which has hitherto barely been reported for other polymers. The phenomenon is discussed in terms of mesoglobule formation (first step) as well as by an unusual distinct disruption of hydrophobic hydration (second step) and hydrogen bonding to the hydrophilic aggregate surface (third step). Macroscopic precipitation only takes place after the third step, a behavior which resembles the denaturation and limited aggregation of proteins. Furthermore, the influence of different anions along the Hofmeister series is investigated, identifying salting‐out (kosmotropic) and salting‐in (chaotropic) effects. As an experimental tool to monitor the thermally induced aggregate growth, dynamic light scattering is used. The reported findings might lead to a more detailed understanding of both aggregation behavior of (biological) macromolecules and mechanistic processes involved in thermoresponsivity and salt‐responsivity of water soluble polymers.
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Gradual Precipitation to Fabricate PLLA Materials with High Porosity and Tunable Strength Formed by High Crystalline Nanosheets
Authors: Yin Guangzhong , Zhao Donglin , Zhang Lianwei , Feng Jianyu , Ren Ye , Chen Guangxin , Zhou Zheng , Li Qifang 
Published: December 2015

In this study, a facile method about generating porous poly (l‐lactide) (PLLA) materials with uniform morphology by gradual precipitation is reported. By adjusting the solvents, concentrations of polymer solution, and drying process, petal‐like PLLA nanosheets can be conveniently obtained, which can further form porous materials with tunable porosities (85–92%). X‐ray diffraction affirms that α‐form crystals of PLLA with high crystallinity (51.66% according to differential scanning calorimetry) can be obtained. Mechanical test shows that the compression modulus is tunable with values ranging from 1.76 to 19.98 MPa. Notably, because of its high porosity, interconnected pore structure, and tunable mechanical properties, these versatile porous materials are especially fit for being utilized in polymer scaffold field.
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One‐Pot Preparation of Organic–Inorganic Composite Microspheres Comprising Silica Nanoparticles and End‐Functionalized Polymers
Authors: Satoh Hiroki , Yabu Hiroshi 
Published: December 2015

Colloidal assemblies of inorganic nanoparticles dispersed in liquid media hold particular promise for the creation of a unique class of functional materials with innovative applications. In the present report, “compound‐eye”‐like core–shell and Janus‐type silica and amino‐terminated 1,2‐polybutadiene (PB‐NH2) and polystyrene (PS) composite microspheres are successfully prepared by simply mixing an aqueous dispersion of silica particles into a tetrahydrofran (THF) solution of PB‐NH2, and PB‐NH2 and PS blends, followed by evaporation of the THF. This co‐precipitation process provides a new approach for producing organic–inorganic composite particles without the need for surface modification of the inorganic nanoparticles.
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MMP20, KLK4, and MMP20/KLK4 double null mice define roles for matrix proteases during dental enamel formation
Authors: Hu Yuanyuan , Smith Charles E. , Richardson Amelia S , Bartlett John D. , Hu Jan C.C. , Simmer James P. 
Published: December 2015

AbstractMatrix metalloproteinase 20 (MMP20) and kallikrein‐related peptidase 4 (KLK4) are secreted proteinases that are essential for proper dental enamel formation. We characterized and compared enamel formed in wild‐type, Mmp20−/−, Klk4−/−, Mmp20+/−Klk4+/−, and Mmp20−/−Klk4−/− mice using dissecting and light microscopy, backscattered scanning electron microscopy (bSEM), SEM, microcomputed tomography (μCT), and energy‐dispersive X‐ray analysis (EDX). Following eruption, fractures were observed on Mmp20−/−, Klk4−/−, Mmp20+/−Klk4+/−, and Mmp20−/−Klk4−/− molars. Failure of the enamel in the Mmp20+/−Klk4+/− molars was unexpected and suggested that digenic effects could contribute to the etiology of amelogenesis imperfecta in humans. Micro‐CT analyses of hemimandibles demonstrated significantly reduced high‐density enamel volume in the Mmp20−/− and Klk4−/− mice relative to the wild‐type, which was further reduced in Mmp20−/−Klk4−/− mice. bSEM images of 7‐week Mmp20−/− and Mmp20−/−Klk4−/− mandibular incisors showed rough, pitted enamel surfaces with numerous indentations and protruding nodules. The Mmp20+/− and Mmp20+/−Klk4+/− incisors showed prominent, evenly spaced, horizontal ridges that were more distinct in Mmp20+/−Klk4+/− incisors relative to Mmp20+/− incisors due to the darkening of the valleys between the ridges. In cross sections, the Mmp20−/− and Mmp20−/−Klk4−/− exhibited three distinct layers. The outer layer exhibited a disturbed elemental composition and an irregular enamel surface covered with nodules. The Mmp20 null enamel was apparently unable to withstand the sheer forces associated with eruption and separated from dentin during development. Cells invaded the cracks and interposed between the dentin and enamel layers. MMP20 and KLK4 serve overlapping and complementary functions to harden enamel by removing protein, but MMP20 potentially serves multiple additional functions necessary for the adherence of enamel to dentin, the release of intercellular protein stores into the enamel matrix, the retreat of ameloblasts to facilitate thickening of the enamel layer, and the timely transition of ameloblasts to maturation.
Obesity and hyperglycemia lead to impaired post‐ischemic recovery after permanent ischemia in mice
Authors: Tulsulkar Jatin , Nada Shadia E. , Slotterbeck Brandon D. , McInerney Marcia F. , Shah Zahoor A. 
Published: December 2015

ObjectiveObesity‐induced diabetes has increased over the years and has become one of the risk factors for stroke. We investigated the influence of diet‐induced obesity and hyperglycemia on permanent distal middle cerebral artery occlusion (pMCAO)‐induced ischemic stroke in mice.MethodsMale C57/Bl6 mice were treated with a high‐fat/high‐carbohydrate diet [HFCD/obese and hyperglycemia (O/H)] or a normal diet (control) for 3.5 months, subjected to pMCAO, and sacrificed after 7 days.ResultsInfarct volume analysis showed no differences between the O/H and control group, whereas neurological deficits were significantly higher in the O/H group compared to the control group. Sirtuin (Sirt1) was overexpressed and NADPH oxidase was reduced in the O/H group. O/H mice had significantly lower expression of Wnt and glycogen synthase kinase 3 α and β, a key component in the Wnt signaling pathway. Translocation of apoptosis inducing factor (AIF) to the nucleus was observed in both the O/H and control groups, but O/H mice showed a higher expression of AIF in the nucleus.ConclusionsThese data suggest that impaired Wnt signaling and active apoptosis result in reduced post‐stroke recovery in obese and hyperglycemic mice.
Nucleolipids of Canonical Purine ß‐d‐Ribo‐Nucleosides: Synthesis and Cytostatic/Cytotoxic Activities Toward Human and Rat Glioblastoma Cells
Authors: Knies Christine , Hammerbacher Katharina , Bonaterra Gabriel A. , Kinscherf Ralf , Rosemeyer Helmut 
Published: December 2015

AbstractWe report on the synthesis of two series of canonical purine ß‐d‐ribonucleoside nucleolipids derived from inosine and adenosine, which have been characterized by elemental analyses, electrospray ionization mass spectrometry (ESI MS) as well as by 1H and 13C NMR, and pH‐dependent UV/Vis spectroscopy. A selection of the novel nucleolipids with different lipophilic moieties were first tested on their cytotoxic effect toward human macrophages. Compounds without a significant inhibitory effect on the viability of the macrophages were tested on their cytostatic/cytotoxic effect toward human astrocytoma/oligodendroglioma GOS‐3 cells as well as against the rat malignant neuroectodermal BT4Ca cell line. In order to additionally investigate the potential molecular mechanisms involved in the cytotoxic effects of the derivatives on GOS‐3 or BT4Ca cells, we evaluated the induction of apoptosis and observed the particular activity of the nucleolipid ethyl 3‐{4‐hydroxymethyl‐2‐methyl‐6‐[6‐oxo‐1‐(3,7,11‐trimethyl‐dodeca‐2,6,10‐trienyl)‐1,6‐dihydro‐purin‐9‐yl]‐tetrahydro‐furo[3,4‐d][1,3]dioxol‐2‐yl}propionate (8 c) toward both human and rat glioblastoma cell lines in vitro.
Thermoelectric efficiency in the linear transport regime
Authors: Eltschka Christopher , Thierschmann Holger , Buhmann Hartmut , Siewert Jens 
Published: December 2015

Improving the efficiency of thermoelectric devices is a long‐term goal in thermoelectricity research. Deeper insight into the meaning of the related quantities, in particular the figure of merit is instrumental for progress in this direction. Here, we study the regime of linear transport where entirely general statements can be made for the electronic part of the thermoelectric efficiency. These results essentially do not depend on the type of device, its layout, or the involved transport mechanisms. For two‐terminal devices, where charge and heat currents flow along the same path, we find a particularly simple and intuitive expression for the figure of merit . In multi‐terminal devices with different paths for the currents, the thermoelectric efficiency does not admit such a simple interpretation. Nonetheless, nontrivial device‐independent statements can be made about the efficiency. As a practical example, we consider the heat‐to‐current converter Sánchez and Büttiker, Phys. Rev. B 83, 085428 (2011) ().
Teratoma: from spontaneous tumors to the pluripotency/malignancy assay
Authors: Bulic‐Jakus Floriana , Katusic Bojanac Ana , Juric‐Lekic Gordana , Vlahovic Maja , Sincic Nino 
Published: December 2015

A teratoma is a benign tumor containing a mixture of differentiated tissues and organotypic derivatives of the three germ layers, while a teratocarcinoma also contains embryonal carcinoma cells (EC cells). Experimental teratomas and teratocarcinomas have been derived from early mammalian embryos transplanted into the adult animal (ectopic sites). In the rat, the pluripotency of the transplanted epiblast was demonstrated and a quantifiable restriction of developmental potential persisted after subsequent transplantation of chemically defined cultivated postimplantation embryos. The rat is nonpermissive for teratocarcinoma development and rat pluripotent cell lines have been established only recently. Transplantation of mouse embryos, epiblast, or embryonic stem cells (mESCs) gave rise to teratocarcinomas. The pluripotency of reprogrammed human cells has been tested by a ‘gold standard’ trilaminar teratoma assay in immunocompromised mice in vivo. Human pluripotent stem cells proposed for use in regenerative medicine such as human embryonic stem cell (hESC), human nuclear‐transfer/therapeutic cloning embryonic stem cell (NT‐ESC), or human induced pluripotent stem cell (hiPSC) lines, once differentiated in vitro to the desired cell type, should be again tested in a long‐term animal teratoma assay to exclude their malignancy. Such an approach led to a recently implemented human therapy with retinal pigmented epithelium. For greater biosafety, the teratoma assay should be standardized and complemented by assessments of mutations/epimutations, RNA/protein expression, and possible immunogenicity of autologous pluripotent cells. Furthermore, the standardized teratoma assay should be directed more to the assessment of EC/malignant cell features than of differentiated tissues, especially after a unique case of human therapy with neural stem cells was found to lead to malignancy. WIREs Dev Biol 2016, 5:186–209. doi: 10.1002/wdev.219This article is categorized under:

Adult Stem Cells, Tissue Renewal, and Regeneration > Methods and Principles
Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cells and Disease
Comparative Development and Evolution > Model Systems
Controlling the properties of surface acoustic waves using graphene
Authors: Bandhu Lokeshwar , Nash Geoffrey R. 
Published: December 2015

Abstract
Surface acoustic waves (SAWs) are elastic waves that propagate on the surface of a solid, much like waves on the ocean, with SAW devices used widely in communication and sensing. The ability to dynamically control the properties of SAWs would allow the creation of devices with improved performance or new functionality. However, so far it has proved extremely difficult to develop a practical way of achieving this control. In this paper we demonstrate voltage control of SAWs in a hybrid graphene-lithium niobate device. The velocity shift of the SAWs was measured as the conductivity of the graphene was modulated using an ion-gel gate, with a 0.1% velocity shift achieved for a bias of approximately 1 V. This velocity shift is comparable to that previously achieved in much more complicated hybrid semiconductor devices, and optimization of this approach could therefore lead to a practical, cost-effective voltage-controlled velocity shifter. In addition, the piezoelectric fields associated with the SAW can also be used to trap and transport the charge carriers within the graphene. Uniquely to graphene, we show that the acoustoelectric current in the same device can be reversed, and switched off, using the gate voltage.
Reciprocal relations between body satisfaction and self‐esteem: A large 13‐year prospective study of adolescents☆
Authors: Wichstrøm Lars , von Soest Tilmann 
Published: December 2015

ABSTRACTPrevious research has demonstrated that body satisfaction and self‐esteem are highly correlated in adolescence, but reasons are poorly understood. We tested three explanations: (i) the two constructs are actually one; (ii) the correlation is explained by a third factor; (iii) there are prospective relationships between body satisfaction and self‐esteem. A population based sample of Norwegian adolescents (n = 3251) was examined four times over a 13‐year period. Confirmatory factor analysis showed that body satisfaction and self‐esteem were separate constructs and the correlation between them was not attenuated when adjusting for 3rd variables. Autoregressive cross‐lagged analysis showed reciprocal relations between body satisfaction and self‐esteem. The prospective relationship between body satisfaction during adolescence and self‐esteem in late adolescence and emerging adulthood was stronger than at later stages.
Parabolic equations and the bounded slope condition
Authors: Duzaar Frank , Marcellini Paolo , Signoriello Stefano , Bögelein Verena 
Published: December 2015

In this paper we establish the existence of Lipschitz-continuous solutions to the Cauchy Dirichlet problem of evolutionary partial differential equations

\begin{cases}
\partial _{t}u−\mathrm{div}\:Df(Du) = 0 &\text{in }\mathrm{\Omega }_{T}\text{,} \\
u = u_{o} &\text{on }\partial _{\mathcal{P}}\mathrm{\Omega }_{T}\text{.}
\end{cases}

The only assumptions needed are the convexity of the generating function

f:\mathbb{R}^{n}\rightarrow \mathbb{R}

, and the classical bounded slope condition on the initial and the lateral boundary datum

u_{o} \in W^{1,\infty }(\mathrm{\Omega })

. We emphasize that no growth conditions are assumed on

f

and that – an example which does not enter in the elliptic case

– u_{o}

could be any Lipschitz initial and boundary datum, vanishing at the boundary

∂Ω

, and the boundary may contain flat parts, for instance

Ω

could be a rectangle in

\mathbb{R}^{n}

.
Cerebrospinal fluid ratios with Aβ42 predict preclinical brain β‐amyloid accumulation
Authors: Racine Annie M. , Koscik Rebecca L. , Nicholas Christopher R. , Clark Lindsay R. , Okonkwo Ozioma C. , Oh Jennifer M. , Hillmer Ansel T. , Murali Dhanabalan , Barnhart Todd E. , Betthauser Tobey J. , Gallagher Catherine L. , Rowley Howard A. , Dowling N. Maritza , Asthana Sanjay , Bendlin Barbara B. , Blennow Kaj , Zetterberg Henrik , Carlsson Cynthia M. , Christian Bradley T. , Johnson Sterling C. 
Published: December 2015

AbstractIntroductionBiomarkers are urgently needed for the critical yet understudied preclinical stage of Alzheimer's disease (AD).MethodsCerebrospinal fluid (CSF) collection, [C‐11]Pittsburgh compound B (PiB) amyloid imaging, and magnetic resonance imaging were acquired in 104 cognitively healthy adults enriched with risk for sporadic AD. Image‐derived cerebral β‐amyloid (Aβ) burden, measured concurrently and longitudinally, was regressed on CSF measures of Aβ, neural injury, and inflammation, as well as ratios with Aβ42. Linear mixed‐effects regression was used to model the effect of the CSF measures that predicted longitudinal brain amyloid accumulation on longitudinal cognitive decline, measured by memory test scores.ResultsAt baseline, Aβ42/Aβ40 and all CSF ratios to Aβ42 were associated with PiB binding in AD‐vulnerable regions. Longitudinally, Aβ42/Aβ40 and ratios of total tau (t‐tau), phosphorylated‐tau (p‐tau), neurofilament light protein, and monocyte chemoattractant protein‐1 to Aβ42 were associated with increased Aβ deposition over 2 years, predominantly in lateral parietal and temporal cortex. However, these CSF ratios were not significantly associated with cognitive decline, and the effect seems to be largely driven by Aβ42 in the denominator.DiscussionThese results corroborate previous findings that t‐tau/Aβ42 and p‐tau/Aβ42 are the strongest candidate biomarkers during the preclinical time frame. They support a framework in which neural injury and amyloid deposition are likely occurring simultaneously. It may be that neurodegenerative processes influence progressive amyloid accumulation, even in the preclinical time frame. CSF biomarkers for nonspecific axonal injury and inflammation may provide more information at more advanced stages of the preclinical time course.