bluuebunny/crossref_metadata_2025 huggingface dataset:
Micro morphological observation and mechanism analysis of boundary layer evolution in mixed powder lubrication
Authors: Wang Chao , Wang Wei , Liu Yong , Liu Kun
Published: December 2017

In mixed‐powder‐lubricated interfaces, the lubrication performance is strongly affected by evolution of the boundary layer features. Therefore, the current investigation uses a laser microscopy system to observe the behaviours of boundary layer formed on the brass specimens during the process of graphite‐lubricated 0.45 C steel (HRC56) sliding upon brass alloy (HV160). The evolution process of mixed powder lubrication can be divided into 4 typical stages: running‐in, stable, deterioration, and damage. Multiple micro phenomena are observed in the boundary layers at different stages. These include extent of layer coverage, flaking, local adhesion, lamellar shedding, blisters, pits, and abrasion damage. These phenomena indicate that the boundary layer deteriorates from full coverage to a damaged powdery film, and eventually the serious wear on metal substrate. Moreover, an interface model of mixed powder lubrication is established to explain the changes in boundary layers. The model displays that the typically micro events above are related to the quantitative degree of overlapping of the asperities between opposing surfaces. At first, many particles bear the load collectively and adapt to velocity differences through inner shearing in powder layer. Later, plastic deformation and abrasion between asperities play a major role in surface velocity accommodation, and the metal substrates bear the load more directly.
Experimental study on mechanical properties of corroded steel fibers under static and dynamic loading
Authors: Chen Hui , Li Bo , Wang Yanru
Published: December 2017

The influences of corrosion and the strain rate on the mechanical performance of corroded steel fibers were assessed in this paper. The steel fibers were corroded to different corrosion degrees by drying‐wetting cycling in a 5% sodium chloride solution and a 50° centigrade oven. The static and dynamic tensile tests of corroded steel fibers were investigated by using a static and dynamic test system. The results showed that the mechanical properties of the corroded steel fibers were strain‐rate dependent. With an increase in strain rate, the ultimate load increased, whereas, the strain‐rate effect decreased with an increase in the corrosion degree. However, variations in Young's modulus with strain rate and corrosion degree were not obvious. With an increase in the corrosion degree, both the nominal tensile strength and elongation of the corroded steel fibers decreased. However, the ultimate strength based on the minimum cross‐sectional area did not decrease. The strength could be attributed to the uneven distribution of the cross‐sectional area along the bar. Based on the experimental results, a time‐dependent assessment method for the mechanical behavior of corroded steel fibers under the static and dynamic loading conditions was proposed.
Assessment of an Objective Method of Dyskinesia Measurement in Parkinson's Disease
Authors: Chung Kathryn A. , Lobb Brenna M. , Murchison Charles F. , Mancini Martina , Hogarth Penelope , Nutt John G.
Published: December 2017

Background

The goal of this study was to validate an objective method of measuring levodopa induced dyskinesia in Parkinson's disease (PD).

Methods

To characterize agreement between the clinician‐based measure and a force plate, we assessed dyskinesia in PD subjects participating in a randomized and blinded clinical trial of an adenosine A2A anatagonist. Convergent validity and intra‐class correlations were evaluated between the objective force plate measure and clinician assessments.

Results

All measures correlated across time and detected differences in treatments.

Conclusion

Our results indicate that objective measure from a force plate is in scale agreement with clinical ratings of dyskinesia severity, indicating it as a reliable method to measure LID objectively but with greater resolution to detect changes in LID.
Inference of economic truth from financial statements for detecting earnings management: inventory costing methods from an information economics perspective
Authors: Herath Hemantha S.B. , Lu Xiaoting
Published: December 2017

We introduce uncertainty in the classic inventory costing choice problem to investigate the underlying partitions imposed by two accounting inquiries (processes of generating information): variable costing and absorption costing. In a contemporaneous reporting environment, we show that absorption costing provides a finer partition of the state space compared to variable costing when a firm arbitrarily increases the production level (opportunistic overproduction), and the predetermined fixed overhead rate is adjusted. Grounded in an information economics perspective, the intent of the article is to propose an approach to detect real earnings management by extracting information from financial statements. The resulting managerial biases arising from earnings management are also discussed.
Basic understanding and therapeutic approaches to target toll‐like receptors in cancerous microenvironment and metastasis
Authors: Khajeh Alizadeh Attar Mojtaba , Anwar Muhammad Ayaz , Eskian Mahsa , Keshavarz‐Fathi Mahsa , Choi Sangdun , Rezaei Nima
Published: December 2017

Toll‐like receptors (TLRs) are transmembrane components that sense danger signals, like damage‐ and pathogen‐associated molecular pattern molecules, as receptors, and maintain homeostasis in tissues. They are mainly involved in immune system activation through a variety of mediators, which either carry out (1) elimination of pathogenic threats and redressing homeostatic imbalances or (2) contribution to the initiation and worsening of pathological conditions, including cancers. Under physiological conditions, TLRs coordinate the innate and adaptive immunity, and inhibit autoimmune disorders. In pathological conditions, such as cancer, they can present both tumor and receptor‐specific roles. Although the roles of individual TLRs in various cancers have been described, the effects of targeting TLRs to treat cancer and prevent metastasis are still controversial. A growing body of literature has suggested contribution of both activators and inhibitors of TLR signaling pathway for cancer treatment, dependent on several context‐specific factors. In short, TLRs can play dual roles with contradictory outcomes in neoplastic conditions. This hampers the development of TLR‐based therapeutic interventions. A better understanding of the interwoven TLR pathways in cancerous microenvironment is necessary to design TLR‐based therapies. In this review, we consider the molecular mechanisms of TLRs signaling and their involvement in tumor progression. Therapeutic modalities targeting TLRs for cancer treatment are discussed as well.
Decision curve analysis as a framework to estimate the potential value of screening or other decision‐making aids
Authors: Martin Michael S. , Wells George A. , Crocker Anne G. , Potter Beth K. , Colman Ian
Published: December 2017

Objectives

There is an increasing debate about the impact of mental health screening. We illustrate the use of a decision making framework that can be applied when there is no sufficient data to support a traditional cost‐benefit analysis.

Methods

We conducted secondary analyses of data from 459 male prisoners who were screened upon intake. We compared the potential benefit of different approaches (screening, history taking, and universal interventions) to allocating treatment resources using decision curve analysis.

Results

Screening prisoners for distress at typical levels of sensitivity (75%) and specificity (71%) were estimated to provide the greatest net benefit if between 2 and 5 false positives per detected illness are tolerable. History taking and self‐harm screening provide the largest net benefit when only 1 or 2 false positives per detected illness would be tolerable. The benefits of screening were less among those without a recent psychiatric history, ethnic minorities, and those with fewer psychosocial needs.

Conclusions

Although screening has potential to increase detection of treatment, important subgroup differences exist. Greater consideration of responses to positive screens or alternatives to screening are needed to maximize the impact of efforts to improve detection and treatment of mental illness.
Triangulation of simple arbitrarily shaped polyhedra by cutting off one vertex at a time
Authors: Zhang Qi‐Hua , Lin Shao‐Zhong , Ding Xiu‐Li , Wu Ai‐Qing
Published: December 2017

We describe a heuristic method of triangulating arbitrarily shaped polyhedra without the addition of Steiner points. The polyhedra are simple, with each vertex connected to at least 3 other vertices (ie, coplanarity and colinearity are not considered). They may, however, be convex or concave and consist of dozens or even hundreds of facets. This makes the treatment universal enough to well meet the requirements of models used to simulate fractured rock masses. Certain concepts are defined in the work, eg, adjacent vertices, polygon of adjacent vertices, and closed cone of a vertex. A polygon of adjacent vertices of an apex can be subdivided into a set of nonoverlapping triangles without adding any vertices. These triangles, together with the apex, form tetrahedra whose union is the closed cone of the apex. The polyhedron is thus the union of the closed cones. Subsequently, we triangulate the polyhedron by gradually removing the closed cones of its vertices. The number of vertices of the polyhedron decreases by one each time a closed cone is removed. A block with n vertices can produce no more than n−3 tetrahedra. We present the analysis procedure and discuss the core issues of the method proposed.
Achieving high thermal and mechanical properties of epoxy nanocomposites via incorporation of dopamine interfaced clay
Authors: Chen Bin , Li Jingyu , Li Xiangyu , Liu Tong , Dai Zhendong , Zhao Haichao , Wang Liping
Published: December 2017

The uniform dispersion of clay in epoxy matrix and strong interfacial bonding between clay platelet and epoxy chains are crucial for achieving epoxy/clay with enhanced thermal and mechanical properties. In this study, dopamine hydrochloride was intercalated into the galleries of clay via ion‐exchange reaction with an aim to improve the dispersion and interfacial bonding with the epoxy matrix. Dopamine intercalated clay (D‐clay) was characterized by X‐ray photoelectron spectrum, Fourier Transform Infrared Spectroscopy, and X‐ray diffraction (XRD), respectively. Epoxy/D‐clay nanocomposites had been prepared by curing process of epoxy E51, Jeffamine D230, and D‐clay with 1, 2, 3, and 4 wt%, respectively. The structure of epoxy/D‐clay nanocomposites was characterized by XRD, scanning electron microscopy, and Transmission electron microscopy, respectively. The enhanced thermal properties and mechanical properties such as tensile strength, tensile modulus, and hardness were enhanced considerably compared with neat epoxy resin. The results found that the inclusion of 3 wt% D‐clay in the epoxy resin showed increase in Tg of 10.09°C, 29.34% increase in tensile strength, 23.19% increase in tensile modulus, and 53.87% increase in vickers hardness compared with neat epoxy resin. The uniform dispersion of clay platelets and strong interfacial hydrogen bonding between D‐clay and epoxy matrix afforded efficient load transfer across the epoxy‐clay interface, leading to significantly improved thermal and mechanical properties. POLYM. COMPOS., 39:E2407–E2414, 2018. © 2017 Society of Plastics Engineers
RNAi technique, how far is it from pediatrics?
Authors: Zhaori Getu
Published: December 2017

The new technology of ribonucleic acid interference (RNAi) or small/short interfering RNA (siRNA) can be used to reduce expression of genes in a sequence specific manner, and thereby can treat various diseases caused by expression or overexpression of genes. Phase 1 and phase 2 clinical studies on application of this technology to treat diseases have demonstrated efficacy and safety of this approach in a few specialties/subspecialties. However, no clinical trials have been reported in the fields of pediatrics. This article aimed to describe very briefly what the RNAi technique is, examples of demonstration of the efficacy and safety of RNAi techniques in a few different fields of clinical medicine, and to encourage pediatricians and pediatric researchers to actively participate in studies on this new therapeutic approach for treatment of various pediatric diseases.
Evolution of cell cracks in PV‐modules under field and laboratory conditions
Authors: Buerhop Claudia , Wirsching Sven , Bemm Andreas , Pickel Tobias , Hohmann Philipp , Nieß Monika , Vodermayer Christian , Huber Alexander , Glück Bernhard , Mergheim Julia , Camus Christian , Hauch Jens , Brabec Christoph J.
Published: December 2017

Damaged modules, especially with cell cracks, can be observed quite often in photovoltaic‐installations. Little knowledge exists about long‐term stability of precracked modules at real operating conditions. Previous investigations and existing standards focus on the degradation of new, defect‐free modules. This work highlights a twofold approach for life‐time study of precracked modules: (1) outdoor exposure of 54 precracked modules for 1 year and (2) artificial stressing of 20 representative precracked modules with a novel load test setup simulating snow and wind loads. The outdoor exposure reveals that at moderate weather conditions, no changes were detectable, neither in electric performance nor in EL‐images. However, the accelerated static load tests with stepwise increasing pressures point out that above a certain threshold, cracks grow. Below this threshold, formerly unseen cracks become visible at the loaded stage. In addition, modules with a smaller number of damaged cells have a stronger tendency to degrade further than modules with an already large number of cracked cells. Remarkably, the power output measured with a solar simulator after a stress test up to 2500 Pa (describing conservative proof conditions for severe snow loads according IEC 61215) remains unchanged for almost all modules.
Bonding and in‐channel microfluidic functionalization using the huisgen cyclization
Authors: Rambarran Talena , Gonzaga Ferdinand , Fatona Ayodele , Coulson Michael , Saem Sokunthearath , Moran‐Mirabal Jose , Brook Michael A.
Published: December 2017

The bonding of layers of silicone elastomers during the manufacturing of microfluidic devices is often accomplished using plasma oxidation. The process can be costly, may require a clean room and materials that ensure the flatness of the bonding layers and, as a consequence of hydrophobic recovery, can lead to high variability in the degree of adhesion. As importantly, the process precludes incorporation of chemical functionalities that work as anchors to immobilize biomolecules within the microfluidic channel. We hypothesized that it would be possible to fabricate microfluidic channels using the Huisgen 1,3‐dipolar cycloaddition of azides to alkynes to crosslink silicones and form PDMS elastomers and, in a subsequent step, bond one PDMS layer to another simply by heating, with the added advantage of producing microfluidic channels with embedded chemical functionalities. After thermal bonding, the microfluidic devices underwent cohesive failure (rupture of the elastomer layer) at ∼145 kPa during pressure tests, but did not exhibit adhesive failure (delamination), showing that the azide–alkyne reaction provides a strong bond between elastomer layers. Furthermore, the internal microfluidic channel surfaces retained alkyne and azide functionality during the process, as shown by the grafting of one or more fluorescent dyes, through Huisgen cyclization. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 589–597
Acetalization of poly(vinyl alcohol) by a fatty aldehyde in water medium: Model study, kinetics, and structure analysis
Authors: Piluso Pierre , Da‐Cruz Boisson Fernande , Bounor‐Legaré Véronique , Espuche Eliane
Published: December 2017

Acid catalyzed poly(vinyl alcohol) (PVA) acetalization was investigated in aqueous medium at 80 °C for a PVA concentration of 8 wt %. The reactant, 10‐undecenal, was composed of a long alkyl chain with a vinyl end group, and the functionalization reaction was studied in heterogeneous media for low reactant concentrations (from 0.33 to 2.0 mol % compared with PVA hydroxyl groups concentration). First, the reaction was scrutinized with pentane‐2,4‐diol, as a model compound of PVA. Besides the expected reaction, the oxidation of the aldehyde into 10‐undecenoic acid in the presence of water was evidenced. This carboxylic acid appeared unreactive toward esterification of pentane‐2,4‐diol and PVA in water. Characterization of acetal stereochemical structure formed on the PVA backbone was performed by NMR spectroscopy in accordance to the model approach. A protocol based on 1H NMR analysis was developed to quantify grafted aldehyde, residual aldehyde, and created carboxylic acid through direct sampling of the reaction medium. Conversions and reaction rate constants were calculated for pH ranging from 1 to 3. Finally, the acetalization yield was found to be enhanced at low pH and, in such conditions, the oxidation reaction contribution was limited. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 661–671
Facile measurement of surface heat loss from polymer thin films via fluorescence thermometry
Authors: Firestone Gabriel , Bochinski Jason R. , Meth Jeffrey S. , Clarke Laura I.
Published: December 2017

Quantitative determination of heat loss and transport within complex systems having inhomogeneous temperatures and several different components is important for applications ranging from electronics to solar cells. An approach and material system to study heat transport within and heat loss from polymer thin films is presented. In a thin film configuration with a cylindrical heating source, the theoretical solution for temperature as a function of radial position can be determined from fundamental principles. Use of embedded fluorescent molecules as temperature probes and manipulation of the relative location of heating and thermometry light sources allows experimental measurements of temperature versus position within the plane of the film. For a large range of practical cases, the exact theoretical solution can be well‐approximated by a single term, which enables a fit to experimental data, and subsequent determination of either the heat loss coefficient at the film's surface or the material's effective thermal conductivity. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 643–651
A Lipidomics Approach to Identifying Key Lipid Species Involved in VEGF‐Inhibitor Mediated Attenuation of Bleomycin‐Induced Pulmonary Fibrosis
Authors: Kulkarni Yogesh M. , Dutta Sucharita , Iyer Anand Krishnan V. , Wright Clayton A. , Ramesh Vani , Kaushik Vivek , Semmes Oliver John , Azad Neelam
Published: December 2017

Purpose

Poor molecular characterization of idiopathic pulmonary fibrosis (IPF) has led to insufficient understanding of the pathogenesis of the disease, resulting in lack of effective therapies and poor prognosis. Particularly, the role of lipid imbalance due to impaired lipid metabolism in the pathogenesis of IPF has been poorly studied.

Experimental design

The authors have used shotgun lipidomics in a bleomycin (BLM) mouse model of pulmonary fibrosis with vascular endothelial growth factor (VEGF)‐inhibitor CBO‐P11 as a therapeutic measure, to identify a comprehensive set of lipids that contribute to the pathogenesis of pulmonary fibrosis.

Results

The authors report that attenuation of BLM‐induced fibrotic response with CBO‐P11 cotreatment is accompanied by a decrease in total lipid content and specific downregulation of lipids, which are upregulated in response to BLM treatment.

Conclusion and clinical relevance

Dysregulated lipids identified in this study hold the potential of being future biomarkers for IPF.
Frequency and circumstances of falls for people with Charcot–Marie–Tooth disease: A cross sectional survey
Authors: Ramdharry Gita M. , Reilly‐O'Donnell Louise , Grant Robert , Reilly Mary M.
Published: December 2017

Objective

People with Charcot–Marie–Tooth (CMT) disease may be at risk of falls due to distal muscle weakness and sensory impairment. We aimed to understand the frequency of falls in a cohort, where they occurred, injury and to what people attributed the possible cause.

Design

A cross‐sectional survey design was used. It was sent by post to ascertain the frequency of falls and near falls, plus the circumstances of the last three falls events they could recall.

Setting

The survey was administered to 252 people with CMT who were patients at a specialist neuromuscular centre.

Participants

People were approached who had a clinical diagnosis by a neuromuscular specialist neurologist.

Interventions

Not applicable.

Main Outcome Measure

The Falls Event Questionnaire.

Results

Responses were received from 107 people with CMT. Falls and near falls were reported by 86% of survey respondents. The majority of falls occurred at home, and muscular weakness appeared to be blamed the most, with participants describing tripping due to foot drop or joints giving way. A similar pattern was observed for near falls, but they tended to be more frequent. Moderate and major injuries were relatively rare, with the majority of falls resulting in scrapes and bruises or the faller feeling shaken by the experience.

Discussion

The impact of falls is far reaching, in terms of injury risk and the consequences of the fear of falling. Interventions to improve balance and reduce falls are an important rehabilitation focus for people with CMT.
Impurity Gettering by Atomic‐Layer‐Deposited Aluminium Oxide Films on Silicon at Contact Firing Temperatures
Authors: Liu AnYao , Macdonald Daniel
Published: December 2017

Aluminium oxide (Al2O3) thin films deposited on silicon surfaces, synthesised by plasma‐assisted atomic layer deposition, are recently reported to possess impurity gettering effects for the silicon wafer bulk during annealing at 425 °C, a typical temperature used for activating the surface passivation quality of the Al2O3 films. This paper investigates the gettering effects of Al2O3 films at higher temperatures of 700–900 °C, which are commonly used for contact firing in silicon solar cell fabrication. Iron is used as a marker impurity in silicon to study the gettering effectiveness. Results show that Al2O3 films also generate strong impurity gettering effects at 700–900 °C, through a segregation gettering mechanism. The as‐deposited Al2O3 films are found to be more effective at gettering than the 425 °C‐activated Al2O3 films, demonstrating gettering processes that are largely limited by the impurity diffusivity in silicon. For both as‐deposited and activated Al2O3 films, gettering during high temperature annealing occurs by impurity accumulation at the Al2O3/Si interfaces, similar to the gettering action at 425 °C. However, some iron is found to redistribute into the bulk of the Al2O3 films after long annealing at a high temperature.
Use of a historical control group in a noninferiority trial assessing a new antibacterial treatment: A case study and discussion of practical implementation aspects
Authors: Dejardin David , Delmar Paul , Warne Charles , Patel Katie , van Rosmalen Joost , Lesaffre Emmanuel
Published: December 2017

When recruitment into a clinical trial is limited due to rarity of the disease of interest, or when recruitment to the control arm is limited due to ethical reasons (eg, pediatric studies or important unmet medical need), exploiting historical controls to augment the prospectively collected database can be an attractive option. Statistical methods for combining historical data with randomized data, while accounting for the incompatibility between the two, have been recently proposed and remain an active field of research. The current literature is lacking a rigorous comparison between methods but also guidelines about their use in practice. In this paper, we compare the existing methods based on a confirmatory phase III study design exercise done for a new antibacterial therapy with a binary endpoint and a single historical dataset. A procedure to assess the relative performance of the different methods for borrowing information from historical control data is proposed, and practical questions related to the selection and implementation of methods are discussed. Based on our examination, we found that the methods have a comparable performance, but we recommend the robust mixture prior for its ease of implementation.
Sensitivity analysis and metamodels for the bulk parametrization of turbulent air–sea fluxes
Authors: Pelletier C. , Lemarié F. , Blayo E.
Published: December 2017

State‐of‐the‐art climate models rely on bulk formulae arising from the Monin–Obukhov semi‐empirical theory to estimate turbulent air–sea fluxes. The mathematical structure of those formulae implies several difficulties when trying to study the numerical properties of coupling algorithms used for practical applications. This article introduces a methodology for building physically realistic approximations of existing bulk formulae which would also satisfy suitable mathematical properties (explicit character, regularity, differentiability). This is achieved by applying the Sobol' method to compute sensitivity indices in order to reduce the number of inputs and derive a simple metamodel for the parametrization of turbulent air–sea fluxes. Numerical results show excellent agreement between our approximations and the standard bulk formulae. In particular, single‐column simulations using the TOGA–COARE experiment within the LMDZ atmospheric model show negligible changes in numerical results.
Sample size determination for jointly testing a cause‐specific hazard and the all‐cause hazard in the presence of competing risks
Authors: Yang Qing , Fung Wing K. , Li Gang
Published: December 2017

This article considers sample size determination for jointly testing a cause‐specific hazard and the all‐cause hazard for competing risks data. The cause‐specific hazard and the all‐cause hazard jointly characterize important study end points such as the disease‐specific survival and overall survival, which are commonly used as coprimary end points in clinical trials. Specifically, we derive sample size calculation methods for 2‐group comparisons based on an asymptotic chi‐square joint test and a maximum joint test of the aforementioned quantities, taking into account censoring due to lost to follow‐up as well as staggered entry and administrative censoring. We illustrate the application of the proposed methods using the Die Deutsche Diabetes Dialyse Studies clinical trial. An R package “powerCompRisk” has been developed and made available at the CRAN R library.
Identifying the Genotypes of Hepatitis B Virus (HBV) with DNA Origami Label
Authors: Liu Ke , Pan Dun , Wen Yanqin , Zhang Honglu , Chao Jie , Wang Lihua , Song Shiping , Fan Chunhai , Shi Yongyong
Published: December 2017

The hepatitis B virus (HBV) genotyping may profoundly affect the accurate diagnosis and antiviral treatment of viral hepatitis. Existing genotyping methods such as serological, immunological, or molecular testing are still suffered from substandard specificity and low sensitivity in laboratory or clinical application. In a previous study, a set of high‐efficiency hybridizable DNA origami‐based shape ID probes to target the templates through which genetic variation could be determined in an ultrahigh resolution of atomic force microscopy (AFM) nanomechanical imaging are established. Here, as a further confirmatory research to explore the sensitivity and applicability of this assay, differentially predesigned DNA origami shape ID probes are also developed for precisely HBV genotyping. Through the specific identification of visualized DNA origami nanostructure with clinical HBV DNA samples, the genetic variation information of genotypes can be directly identified under AFM. As a proof‐of‐concept, five genotype B and six genotype C are detected in 11 HBV‐infected patients' blood DNA samples of Han Chinese population in the single‐blinded test. The AFM image‐based DNA origami shape ID genotyping approach shows high specificity and sensitivity, which could be promising for virus infection diagnosis and precision medicine in the future.
Biological Functions and Current Advances in Isolation and Detection Strategies for Exosome Nanovesicles
Authors: Boriachek Kseniia , Islam Md. Nazmul , Möller Andreas , Salomon Carlos , Nguyen Nam‐Trung , Hossain Md. Shahriar A. , Yamauchi Yusuke , Shiddiky Muhammad J. A.
Published: December 2017

Exosomes are nanoscale (≈30–150 nm) extracellular vesicles of endocytic origin that are shed by most types of cells and circulate in bodily fluids. Exosomes carry a specific composition of proteins, lipids, RNA, and DNA and can work as cargo to transfer this information to recipient cells. Recent studies on exosomes have shown that they play an important role in various biological processes, such as intercellular signaling, coagulation, inflammation, and cellular homeostasis. These functional roles are attributed to their ability to transfer RNA, proteins, enzymes, and lipids, thereby affecting the physiological and pathological conditions in various diseases, including cancer and neurodegenerative, infectious, and autoimmune diseases (e.g., cancer initiation, progression, and metastasis). Due to these unique characteristics, exosomes are considered promising biomarkers for the diagnosis and prognosis of various diseases via noninvasive or minimally invasive procedures. Over the last decade, a plethora of methodologies have been developed for analyzing disease‐specific exosomes using optical and nonoptical tools. Here, the major biological functions, significance, and potential role of exosomes as biomarkers and therapeutics are discussed. Furthermore, an overview of the most commonly used techniques for exosome analysis, highlighting the major technical challenges and limitations of existing techniques, is presented.
Low‐Temperature Processed Nanostructured Rutile TiO2 Array Films for Perovskite Solar Cells With High Efficiency and Stability
Authors: Wu Shufang , Cheng Chi , Jin Jingpeng , Wang Jinming , Peng Tianyou
Published: December 2017

The rutile TiO2 array (RTA) films consisting of vertically oriented nanoneedles and/or nanosheets are grown on a fluorine‐doped tin oxide (FTO) glass substrate via a chemical bath deposition (CBD) process at 70 °C, and are utilized as electron transport layer (ETL) for CH3NH3PbI3‐based perovskite solar cells (PSCs). The morphology and microstructure of the RTA films can be tuned by varying the CBD time. A mixed nanoneedles/nanosheets array film (∼250 nm thickness) derived from 60 min CBD process achieve a power conversion efficiency (PCE) up to 15.4% with reduced hysteresis, improved reproducibility, and stability as compared to those PSCs based on traditional mesoscopic‐TiO2 or planar‐TiO2 ETLs, which is due to the lower charge recombination, more efficient hole‐blocking, and electron transport. After aging and storage in the dark, the optimal PSC exhibits a slightly improved PCE (16.3%), which is the highest one among those CH3NH3PbI3‐based PSCs fabricated with low‐temperature processed RTAs reported previously. This work is the first example of vertically oriented nanosheets and/or nanoneedles RTA film grown on a conductive glass to serve as ETL of PSC, and the low‐temperature procedure of the RTA film paves a promising low‐cost way for fabricating large‐scale PSCs.
Bmi1+ Progenitor Cell Dynamics in Murine Cornea During Homeostasis and Wound Healing
Authors: Kalha Solja , Shrestha Bideep , Sanz Navarro Maria , Jones Kyle B. , Klein Ophir D. , Michon Frederic
Published: December 2017

The outermost layer of the eye, the cornea, is renewed continuously throughout life. Stem cells of the corneal epithelium reside in the limbus at the corneal periphery and ensure homeostasis of the central epithelium. However, in young mice, homeostasis relies on cells located in the basal layer of the central corneal epithelium. Here, we first studied corneal growth during the transition from newborn to adult and assessed Keratin 19 (Krt19) expression as a hallmark of corneal maturation. Next, we set out to identify a novel marker of murine corneal epithelial progenitor cells before, during and after maturation, and we found that Bmi1 is expressed in the basal epithelium of the central cornea and limbus. Furthermore, we demonstrated that Bmi1+ cells participated in tissue replenishment in the central cornea. These Bmi1+ cells did not maintain homeostasis of the cornea for more than 3 months, reflecting their status as progenitor rather than stem cells. Finally, after injury, Bmi1+ cells fueled homeostatic maintenance, whereas wound closure occurred via epithelial reorganization.
Ecosystem engineers in rivers: An introduction to how and where organisms create positive biogeomorphic feedbacks
Authors: Polvi Lina E. , Sarneel Judith M.
Published: December 2017

Ecosystem engineers substantially alter physical flow characteristics and shape a river's form and function. Because the recurrence interval of geomorphic processes and disturbances in rivers commonly match the temporal scale of plants’ life cycles or alterations by animals, the resulting feedbacks are an important component of rivers. In this review, we focus on biota that directly or indirectly induce a physical change in rivers and cause positive feedbacks on the functioning of that organism. We provide an overview of how various ecosystem engineers affect rivers at different temporal and spatial scales and plot them on a conceptual gradient of river types. Various plants engineer the river environment through stabilizing sediment and reducing flow velocities, including macrophytes, woody plants, and algal mats and biofilms. Among animals that engineer, beaver that build dams cause substantial changes to river dynamics. In addition, benthic macroinvertebrates and mussels can stabilize sediment and reduce velocities, and aquatic and riparian grazers modulate the effect of plants. Humans are also considered river ecosystem engineers. Most of the ecosystem engineers reported in literature occur in rivers with low to intermediate relative stability, intermediate channel widths, and small to intermediate grain sizes. Ecosystem engineers that create positive biogeomorphic feedbacks are important to take into account when managing river systems, as many common invasive species are successful due to their engineering capabilities. River restoration can use ecosystem engineers to spur holistic recovery. Future research points towards examining ecosystem engineers on longer spatial and temporal scales and understanding the co‐evolution of organisms and landforms through engineering. WIREs Water 2018, 5:e1271. doi: 10.1002/wat2.1271

This article is categorized under:

Water and Life > Nature of Freshwater Ecosystems

Water and Life > Conservation, Management, and Awareness
Inductive reasoning 2.0
Authors: Hayes Brett K. , Heit Evan
Published: December 2017

Inductive reasoning entails using existing knowledge to make predictions about novel cases. The first part of this review summarizes key inductive phenomena and critically evaluates theories of induction. We highlight recent theoretical advances, with a special emphasis on the structured statistical approach, the importance of sampling assumptions in Bayesian models, and connectionist modeling. A number of new research directions in this field are identified including comparisons of inductive and deductive reasoning, the identification of common core processes in induction and memory tasks and induction involving category uncertainty. The implications of induction research for areas as diverse as complex decision‐making and fear generalization are discussed.

This article is categorized under:

Psychology > Reasoning and Decision Making

Psychology > Learning
The elemental composition of Stradivari's musical instruments: new results through non‐invasive EDXRF analysis
Authors: Rovetta T. , Invernizzi C. , Licchelli M. , Cacciatori F. , Malagodi M.
Published: December 2017

During recent decades, many researchers have tried to understand the main influences on the extraordinary sound and beauty of the masterpieces made by the ancient violin makers. This is still a challenge for many others today. Mainly because of a lack of written historical documents, the rediscovery of some of the ancient violin‐making processes was made possible thanks to scientific analyses performed on their materials by means of diagnostic techniques. However, understanding which substances were adopted is a very hard task, because the analyses are influenced by many factors: for example, alterations, wear, retouches, and the heterogeneity of materials. This paper presents some new EDXRF results collected on eight‐stringed musical instruments made by Antonio Stradivari between 1669 and 1734 (“Clisbee” 1669, “Hellier” 1679, “Ford‐Rougemont” 1703, “Joachim‐Ma” 1714, “Russian Federation” viola 1715, “Cremonese” 1715, “Vesuvius” 1727, and “Scotland” 1734) and now preserved at the Museo del Violino in Cremona. A brief comparison with a modern violin made by Simone Ferdinando Sacconi (“Hellier copy” 1941), one of the most eminent violin makers of the 20th century and one of the greatest experts on Stradivari's work, is also provided. This represents the first comparative analysis of a wide number of ancient musical instruments made by the same violin maker over an extended period. A non‐destructive and non‐invasive approach was followed to (a) understand the elemental composition differences between the best conserved and most worn‐out surfaces; (b) check if there are elemental similarities among the finishing materials of violins made in different years by the same violin maker; (c) give new suggestions about the materials used. To distinguish the best conserved areas from the worn‐out ones, a preliminary investigation by UV‐induced fluorescence photography was performed. In addition, stereomicroscopic observations and Fourier transform infrared spectroscopy (FTIR) analyses were performed on selected areas to validate the hypotheses. The results, in some cases comparable with previous research on Stradivari instruments, have increased the pool of information about materials and treatments adopted in the Stradivari workshop.
Long-term Hydrochemical Earthquake Precursor Studies at the Koyna-Warna Reservoir Site in Western India
Authors: Reddy D. V. , Kumar Devender , Rao N. Purnachandra
Published: December 2017

Koyna-Warna region of western India is an active seismic zone due to the Reservoir Triggered Seismicity (RTS). Earthquake precursor studies are carried out monitoring hydrochemical and stable isotope signatures in the groundwater from 15 bore wells since January 2005, for more than 12 years (January 2005 to February 2017). Depth of these boreholes ranges from 100 to 250 m. Cyclic or temporal variation in hydrochemistry is observed in few sensitive wells in Koyna region. The Govare well in Koyna is found to be most sensitive and the observed hydrochemical cycle is closely associated with local earthquakes of M > 5. The earth-quakes M <5 occurring either in Warna cluster or close to the observation wells, did not generate hydrochemical precursory changes. The increase in hydrochemistry is hypothesized as mixing of two aquifer waters with different hydrochemistry. It is noted that a precursory hydrochemical cycle is observed during first quarter of 2015, but no earthquake M > 5.0 occurred till date. The cyclic changes in hydrochemistry, however, indicate on-going earthquake processes and an impending earthquake of M > 5 in the region.
Sustained Seismicity near Koyna-Warna Reservoir: A Mish-mash of Physical Processes
Authors: Gahalaut Kalpna , Gahalaut Vineet K.
Published: December 2017

Earthquakes in Koyna-Warna region are triggered by the reservoirs but the reasons for sustained seismicity, in terms of magnitude and time, remain enigmatic. We critically review the proposed models/processes, which include fault interaction, flexure of Western Ghat escarpment, velocity heterogeneity, and earthquakes being considered as aftershocks. We suggest that each of these processes or models have limitations and are not capable of explaining all the features of seismicity individually. It is possible that all put together and some other unknown additional processes are at work and there is a mish-mash of several processes attending the region, causing continuing seismicity for past five decades.
Rock Strength and Elastic Properties of Basement Granitoids from Koyna Region, Deccan Volcanic Province, India
Authors: Goswami Deepjyoti , Akkiraju Vyasulu V. , Singh Santosh K. , Shalivahan  , Roy Sukanta
Published: December 2017

Unconfined compressive strength measurements on 20 borehole core samples constrain the elastic properties of basement granitoids underlying the Deccan basalts in the Koyna region for the first time. Test specimens were taken from the basement section below 1251 m depth in borehole KBH-7, which is located in proximity to the Donichawadi surface rupture associated with the 1967 M6.3 Koyna earthquake. Specimens of granite, granite-gneiss and migmatitic gneiss were tested in the laboratory under dry state and room temperature. Salient results of the study are as follows: (i) The granitoids are characterised by variable compressive strength in the range 22-98 MPa, (ii) Stress-strain response of the basement rock indicate varying degrees of deformation even for the same rock type. (iii) Young’s modulus and Poisson’s ratio of the granitoids, computed from the linear elastic portion of the stress-strain curves, vary in the range 8-23 GPa and 0.1-0.3 respectively, (iv) The low and variable rock strength of the Koyna granitoids when compared to granitic rocks from aseismic areas indicates their generally weak nature, probably induced by the recurrent seismicity in the Koyna seismogenic zone.
High Resolution Core Scan Facility at BGRL-MoES, Karad, India
Authors: Tiwari Sanjay , Mishra Satrughna , Srihariprasad G. , Vyas Digant , Warhade Ashish , Nikalje Dinesh , Bartakke Vikrant , Mahesh B. , Tembhurnikar Pallavi , Roy Sukanta
Published: December 2017

A high-resolution, optical core scan laboratory has been set up at Borehole Geophysics Research Laboratory (BGRL), Ministry of Earth Sciences (MoES), Karad. The facility provides a DMT® CoreScan3 optical core scanner and digital drill core data management system for core logging and analysis since July 2016. High resolution images are being produced in 360° mode for detailed unwrapped full circumference of drill core or plane mode for top surface image of slabbed drill core. Planar images of fractured cores and cuttings are also obtained. Image resolution ranges from 5 pix/mm (∼16 megapixel equivalent) to 40 pix/mm (∼1024 megapixel equivalent) for mapping of ultra high resolution data. The scanned core images are combined to create a digital core library. The facility helps in core sample analysis, structural analysis, textural and grain-size analysis, geotechnical studies, and integration with geophysical log data.
Bullying and negative appearance feedback among adolescents: Is it objective or misperceived weight that matters?
Authors: Lee Kirsty , Dale Jeremy , Guy Alexa , Wolke Dieter
Published: December 2017

This study investigated (1) whether involvement in bullying as a bully, victim or bully‐victim was associated with objectively measured overweight or underweight, or whether it was related to weight misperception (i.e., inaccurate perceptions), and (2) whether appearance‐specific feedback mediated the relationship between bullying and weight misperception. In Stage 1, 2782 adolescents aged 11–16 years from British secondary schools were screened for peer bullying and victimisation. In Stage 2, 411 adolescents with weight and height data (objective n = 319, self‐report n = 92) also self‐reported on their weight perception and appearance‐specific feedback. Neither bullying nor victimisation were related to objective underweight or overweight. Victims were at increased odds of overweight misperception, while bully‐victims were at increased odds of underweight misperception. Additionally, there was an indirect effect of appearance feedback on overweight misperception in bully‐victims. Both victims and bully‐victims are at increased risk of weight misperception, posing further detrimental effects to their health and wellbeing.
Overview of colorectal resections in a reference center in Curitiba – Brazil: Experience with open and laparoscopic approach
Authors: Domingos Micheli Fortunato , Pinho Renato Valmassoni , Coelho Júlio Cezar Uili , Ferronatto Guilherme Figueiró , Savio Mariane Christina , Blum Caroline , Weiss Andre Gubert , Aguilera Yan Sacha Hass
Published: December 2017

Introduction Minimally invasive approach has become the preferential option for the treatment of surgical diseases of the Gastrointestinal Tract, due to its numerous advantages. However, in the Colorectal Surgery field, the acceptance of videolaparoscopy was slower. For example, an American study showed that the percentage of laparoscopic cholecystectomy increased from 2.5% in 1988 to 73.7% in 1992, the rate of laparoscopic sigmoidectomy increased from 4.3% in 2000 to only 7.6% in 2004.

Objecties Our goal was to compare several variables between patients submitted to colorectal resections performed through open surgery or videolaparoscopy.

Methods This is a retrospective observational study performed in a Teaching Private Hospital of the City of Curitiba, Brazil, with the revision of 395 medical charts of patients subjected to colorectal resections from January 2011 through June 2016.

Results 349 patients were included in the study. 243 (69.6%) were subjected to laparoscopic colon resection (LCR) and 106 (30.4%) to open colon resection (OCR). Mean age was 62.2 years for patients undergoing LCR and 68.8 year for OCR (p = 0.0082). Among emergency procedures, 92.5% consisted of OCR and 7.5% were LCRs. Surgery duration was similar in both types of access (196 min in OCR versus 195 min in LCR; p = 0.9864). Diet introduction was earlier in laparoscopic surgery and anastomotic fistula rate was similar in both groups (OCR 7.5% and LCR 6.58%; p = 0.7438). Hospital stay was shorter in patients undergoing laparoscopic resections (7.53 ± 7.3 days) than in the ones undergoing open surgery (17.2 ± 19.3) (p < 0.001). In the OCR group, 70 patients needed ICU admission (66%), and stayed a mean of 12.3 days under intensive care. In the LCR group, however, only 30 needed ICU (12.3%), and the ones who needed it stayed a mean of 5.6 days (p < 0.001).

Conclusions Videolaparoscopic approach is a safe and effective option in the treatment of colorectal diseases. Surgery duration and anastomotic fistula rates are similar to the open resections. Hospital stay and ICU stay durations, however, were shorter in patients submitted to laparoscopic colectomies.
SPACE OF RICCI FLOWS (II)—PART A: MODULI OF SINGULAR CALABI–YAU SPACES
Authors: CHEN XIUXIONG , WANG BING
Published: December 2017

We establish the compactness of the moduli space of noncollapsed Calabi–Yau spaces with mild singularities. Based on this compactness result, we develop a new approach to study the weak compactness of Riemannian manifolds.