bluuebunny/crossref_metadata_2025 huggingface dataset:
Independent Roles of Estrogen Deficiency and Cellular Senescence in the Pathogenesis of Osteoporosis: Evidence in Young Adult Mice and Older Humans
Authors: Farr Joshua N , Rowsey Jennifer L , Eckhardt Brittany A , Thicke Brianne S , Fraser Daniel G , Tchkonia Tamar , Kirkland James L , Monroe David G , Khosla Sundeep
Published: March 2019

Estrogen deficiency is a seminal mechanism in the pathogenesis of osteoporosis. Mounting evidence, however, establishes that cellular senescence, a fundamental mechanism that drives multiple age-related diseases, also causes osteoporosis. Recently, we systematically identified an accumulation of senescent cells, characterized by increased p16Ink4a and p21Cip1 levels and development of a senescence-associated secretory phenotype (SASP), in mouse bone/marrow and human bone with aging. We then demonstrated that elimination of senescent cells prevented age-related bone loss using multiple approaches, eg, treating old mice expressing a “suicide” transgene, INK-ATTAC, with AP20187 to induce apoptosis of p16Ink4a-senescent cells or periodically treating old wild-type mice with “senolytics,” ie, drugs that eliminate senescent cells. Here, we investigate a possible role for estrogen in the regulation of cellular senescence using multiple approaches. First, sex steroid deficiency 2 months after ovariectomy (OVX, n = 15) or orchidectomy (ORCH, n = 15) versus sham surgery (SHAM, n = 15/sex) in young adult (4-month-old) wild-type mice did not alter senescence biomarkers or induce a SASP in bone. Next, in elderly postmenopausal women, 3 weeks of estrogen therapy (n = 10; 74 ± 5 years) compared with no treatment (n = 10; 78 ± 5 years) did not alter senescence biomarkers or the SASP in human bone biopsies. Finally, young adult (4-month-old) female INK-ATTAC mice were randomized (n = 17/group) to SHAM+Vehicle, OVX+Vehicle, or OVX+AP20187 for 2 months. As anticipated, OVX+Vehicle caused significant trabecular/cortical bone loss compared with SHAM+Vehicle. However, treatment with AP20187, which eliminates senescent cells in INK-ATTAC mice, did not rescue the OVX-induced bone loss or alter senescence biomarkers. Collectively, our data establish independent roles of estrogen deficiency and cellular senescence in the pathogenesis of osteoporosis, which has important implications for testing novel senolytics for skeletal efficacy, as these drugs will need to be evaluated in preclinical models of aging as opposed to the current FDA model of prevention of OVX-induced bone loss. © 2019 American Society for Bone and Mineral Research.
When do workarounds help or hurt patient outcomes? The moderating role of operational failures
Authors: Tucker Anita L. , Zheng Sarah , Gardner John W. , Bohn Roger E.
Published: March 2019

Hospital providers often use workarounds to circumvent processes so that patients can receive care. Workarounds in response to operational failures enable care to continue and therefore may be indicative of workers' commitment. On the other hand, workarounds in the absence of operational failures may signal an ineffective approach associated with lower quality of care and worse patient outcomes. Working closely with healthcare providers, we developed a survey to measure workaround behaviors and operational failures on medical/surgical units. The lead author surveyed over 4,000 nurses from 63 hospitals throughout the United States. We matched this data with audit data on the incidence of pressure injuries among over 21,000 patients on 262 nursing units in 56 survey hospitals. Hospital‐acquired pressure injuries are a significant risk to patient health and hospital costs. We do not find support for our hypothesis that workarounds are associated with a higher rate of hospital‐acquired pressure injuries. However, when we take into account the moderating role of operational failures on the relationship between workarounds and pressure injuries, we find significant results. When nursing units have lower levels of operational failures, workarounds are associated with higher rates of hospital‐acquired pressure injuries. Our results provide evidence that workarounds may be associated with negative patient outcomes, if they stem from a process‐avoiding approach. The best results can be achieved by reducing both operational failures and workarounds via instilling a process‐focused approach.
Diagnostic Performance of Automated Breast Ultrasound in Differentiating Benign and Malignant Breast Masses in Asymptomatic Women: A Comparison Study With Handheld Ultrasound
Authors: Niu Lin , Bao Lingyun , Zhu Luoqian , Tan Yanjuan , Xu Xiaojing , Shan Yanna , Liu Jian , Zhu Qingqing , Jiang Chenxiang , Shen Yingzhao
Published: March 2019

Objectives

Our aim was to investigate the diagnostic potential of an automated breast ultrasound (ABUS) system in differentiating benign and malignant breast masses compared with handheld ultrasound (HHUS).

Methods

Women were randomly and proportionally selected from outpatients and underwent both HHUS and ABUS examinations. Masses with final American College of Radiology Breast Imaging Reporting and Data System categories 2 and 3 were considered benign. Masses with final Breast Imaging Reporting and Data System categories 4 and 5 were considered malignant. The diagnosis was confirmed by pathologic results or at least a 1‐year follow‐up. Automated breast US and HHUS were compared on the basis of their sensitivity, specificity, positive predictive value, negative predictive value, and accuracy. Diagnostic consistency and areas under the receiver operating characteristic curves were analyzed. The maximum diameters of masses were compared among HHUS, ABUS, and pathologic results.

Results

A total of 599 masses in 398 women were confirmed by pathologic results or at least a 1‐year follow‐up; 103 of 599 masses were malignant, and 496 were benign. There were no significant differences between ABUS and HHUS in terms of diagnostic accuracy (80.1% versus 80.6%), specificity (77.62% versus 80.24%), positive predictive value (46.12% versus 46.46%), and negative predictive value (97.96% versus 95.67%). There were significant differences in sensitivity (92.23% versus 82.52%;P < .01) and areas under the curve (0.85 versus 0.81;P < .05) between ABUS and HHUS. The correlation of the maximum diameter was slightly higher between ABUS and pathologic results (r = 0.885) than between HHUS and pathologic results (r = 0.855), but the difference was not significant (P > .05).

Conclusions

Automated breast US is better than HHUS in differentiating benign and malignant breast masses, especially with respect to specificity.
Ultrasound Imaging for Detecting Metastasis to Level II and III Axillary Lymph Nodes after Axillary Lymph Node Dissection for Invasive Breast Cancer
Authors: Lin Xi , An Xin , Xiang Huiling , Pei Xiaoqing , Li Anhua , Tang Guoxue
Published: March 2019

Objectives

The diagnostic value of axillary ultrasound (US) for level II and III axillary lymph node metastasis after axillary lymph node dissection for invasive breast cancer is currently not clear. The objectives of this study were to retrospectively analyze the diagnostic value of axillar US for level II and III axillary lymph node metastasis and compare it with palpation and to analyze the US features of level II and III axillary lymph nodes that are predictive of metastatic recurrence during follow‐up.

Methods

Cases with level II or III axillary lymph nodes detected by US between January 2005 and December 2017 at a cancer center were divided into 2 groups according to a retrospective analysis of US findings: potential malignancy group and follow‐up group. Biopsy was performed in all patients in the potential malignancy group. In the follow‐up group, the patients were followed for at least 2 years, and biopsy was performed if suspicious US features were detected.

Results

The 401 enrolled cases were followed by axillary US and physical examination (PE) for comparison. Finally, 55 axillary metastases were pathologically confirmed (14%). The sensitivity, specificity, and area under the receiver operating characteristic curve for axillary US were 92.7%, 93.9%, and 0.933, respectively, and the corresponding values for PE were 49.1%, 91.3%, and 0.702 (P < .001). An increase in the major or minor axis diameter of the lymph nodes of greater than 2 mm, a Solbiati index value of less than 1.5, and the presence of new suspicious lesions in other regions were significant predictors of lymph node metastasis based on the US findings (P = .013, .006, .015, and .036).

Conclusions

Axillary is helpful in the follow‐up of level II and III axillary lymph nodes after axillary lymph node dissection for invasive breast cancer and can detect cancer recurrence earlier than PE.
A cross‐sectional follow‐up study of physical morbidities, neurocognitive function, and attention problems in post‐treatment childhood acute lymphoblastic leukemia survivors
Authors: Chiou Shyh‐Shin , Lin Pei‐Chin , Liao Yu‐Mei , Yang Pinchen
Published: March 2019

Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. While ALL therapies are highly effective, western studies have shown excesses late life effects of therapies in survivors. In this survey, we recruited subjects being diagnosed as ALL before the age of 18‐year‐old and had been in complete continuous remission for at least 3 years. Subjects were arranged to receive three cognitive tests (Wechsler intelligence test, Conners' continuous performance test, and Wisconsin card sorting test). Standardized questionnaires were used to inquiry about attention problem in real life context. Treatment outcome were compared between the standard risk and high/very high risk groups. Final survivors were 42 subjects (26 males, 16 females) with median current age of 17.8 years. Subjects were diagnosed to be with ALL at a median age of 4.8 years. The median survival time (from discontinuation of ALL treatment to the study date) was 8.4 years. Results indicated that 17 subjects (40.5%) had chronic physical conditions in need of clinical management and six subjects (14.3%) had mental condition. For the performance‐based cognitive outcome, the average full scale intelligence quotient was 91.7 ± 13.8. Ten percent of the subjects had problem in test of attention, 20% had problem in test of impulsivity and 42.8% of the subject had problems in executive function. When judged from real life contexts, 19 subjects (42%) were with obvious attention problems. Group comparison between standard risk vs high/very high risk patients revealed no difference in neurocognitive outcomes. We hope that this information may benefit the implementation of follow‐up program for Taiwanese pediatric leukemia survivors.
EDC‐Mediated Grafting of Quaternary Ammonium Salts onto Chitosan for Antibacterial and Thermal Properties Improvement
Authors: Oyervides‐Muñoz Ernesto , Avérous Luc , Sosa‐Santillán Gerardo de Jesús , Pollet Eric , Pérez‐Aguilar Nancy Verónica , Rojas‐Caldera Claudia Maribel , Fuentes‐Avilés José Guadalupe , García‐Astrain Clara
Published: March 2019

The present study provides antibacterial and thermal improvements of chitosan‐based systems through chemical modification with different quaternary ammonium salts using 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide (EDC) as mediator. Three different ammonium salts with a carboxylic acid end group are synthesized through a quaternization reaction between bromohexanoic acid and the respective tertiary amines (quinoline, N,N‐dimethylbenzylamine and pyridine). They are then chemically grafted along the chitosan backbone using EDC as a carboxyl activating agent for the coupling with the primary amine groups. This allows three different chitosan derivatives to be obtained: Quinolinium‐Chitosan (QA‐Cs), Benzalkonium‐Chitosan (BK‐Cs), and Pyridinium‐Chitosan (PA‐Cs), respectively. The chemical structures are characterized by 1H NMR analysis. The thermal stability is analyzed by thermogravimetric analysis. Antibacterial efficiencies of chitosan derivatives against Pseudomonas aeruginosa and Staphylococcus aureus strains are determined. All the chitosan derivatives show negligible antibacterial activity against Gram‐positive S. aureus strain. However, the antibacterial activity against Gram‐negative P. aeruginosa strain is significantly improved.
Facile Synthesis of Helical Rod–Coil Block Polymers by the Combination of ATRP and Pd(II)‐Initiated Isocyanides Polymerizations
Authors: Liu Na , Lu Hao‐Jun , Jiang Zhi‐Qiang , Lu Yu‐Bing , Zou Hui , Zhou Li , Wu Zong‐Quan
Published: March 2019

A bifunctional initiator containing propargyl bromoisobutyrate and alkyne‐Pd(II) (PBB‐Pd(II)) is designed and synthesized. The propargyl bromoisobutyrate unit of PBB‐Pd(II) can initiate the atom transfer radical polymerization (ATRP) of vinyl monomers, while the Pd(II) complex can initiate the polymerization of phenyl isocyanides. Both the ATRP and Pd(II)‐mediated isocyanide polymerization are proceeded in living/controlled manner. Thus, combining the two living polymerizations, a series of well‐defined block copolymers bearing rod poly(phenyl isocyanide)s and coil poly(acrylate) segments can be facilely prepared in high yield with tunable composition, controlled molar masses (Mns), and narrow molar mass distributions (Mw/Mns). What is more, benefiting from this synthetic strategy, well‐defined core cross‐linked star polymers are readily synthesized. Optically active block copolymers and star polymers can be facilely obtained by using chiral isocyanide monomers due to the formation of predominated one‐handed helix. The chiral star polymers show excellent enantioselective recognition ability in enantioselective crystallization of racemic compounds.
Semilinear subdiffusion with memory in multidimensional domains
Authors: Krasnoschok Mykola , Pata Vittorino , Vasylyeva Nataliya
Published: March 2019

For , we investigate the nonlinear integro‐differential equation on a multidimensional space domain urn:x-wiley:0025584X:media:mana201700405:mana201700405-math-0003where is the Caputo fractional derivative and and are uniform elliptic operators with smooth coefficients depending on time. Under suitable conditions on the nonlinearity, the global existence and uniqueness of the classical solution to the related initial and boundary value problems are established.
pyReSpect: A Computer Program to Extract Discrete and Continuous Spectra from Stress Relaxation Experiments
Authors: Shanbhag Sachin
Published: March 2019

An open‐source software package “pyReSpect” is presented to extract relaxation spectra from stress relaxation experiments. It employs nonlinear Tikhonov regularization to obtain the continuous relaxation spectrum (CRS), and robust new algorithm to automatically determine a discrete relaxation spectrum (DRS) with a parsimonious number of modes. The new algorithm uses the CRS to guess the location of the modes, a nonlinear least squares optimization to fine‐tine the guess, and an information criterion to determine an optimal number of modes. The program is subjected to three validation tests, where data are generated from synthetic spectra, and three additional tests drawn from a variety of macromolecular architectures and sources. On the validation tests, pyReSpect is able to extract the original spectra. In all cases, the DRS follows the shape of the CRS, and offers additional regularization. Overall, pyReSpect is an excellent choice to obtain the DRS when the number and placement of modes is not known in advance.
Modelling long term monthly rainfall using geographical inputs: assessing heuristic and geostatistical models
Authors: Kisi Ozgur , Mohsenzadeh Karimi Sahar , Shiri Jalal , Keshavarzi Ali
Published: March 2019

Modelling rainfall, an important element of the hydrological cycle, is of crucial importance in hydrology, water resources engineering, irrigation scheduling and environmental issues. In the current study, the monthly rainfall amounts were simulated through the least squares support vector machine (LSSVM), the model tree (MT) and the geostatistical kriging approaches using geographical inputs. So, the latitude, longitude, altitude and the periodicity component were introduced as model inputs for simulating monthly rainfall values. Long‐term rainfall records from 73 weather stations covering different climatic contexts of Iran were used for developing and evaluating the proposed methodology. Two modelling scenarios, namely the at station and pooled scenarios, were carried out for assessing the capability of the applied models in modelling rainfall values. First, two different heuristic methods, the LSSVM and MT methods, were compared with each other. The results obtained revealed that the LSSVM model produced more accurate results than the MT for the at station scenario. Both methods gave better results in arid/semi‐arid regions than humid stations. In the pooled scenario, the rainfall data of humid and arid training stations were pooled and used for calibration and then tested at each station. In this scenario, the LSSVM was superior to the MT in modelling long‐term monthly rainfall. The LSSVM and MT models were then compared with the geostatistical kriging method in both scenarios. It was observed that the kriging method generally performed better than the heuristic methods in spatial modelling of rainfall.
Fractional solution of the catenary curve
Authors: Martínez–Jiménez Leonardo , Cruz–Duarte Jorge Mario , Rosales–García J. Juan
Published: March 2019

The catenary curve has been used in a vast number of practical applications, and several mathematical models have been studied to approximate its behavior. This work, motivated by the success of fractional calculus, proposes a fractional model for the catenary curve, using the Caputo‐Fabrizio (CF) definition. It was analyzed how the fractional derivative order and the fractional initial condition directly affect the hanging cable shape. It was noticed that the proposed model provides the possibility of describing new scenarios and revealing new information about the system. Therefore, this work gives rise to a new family of curves that can be used in any practical problem involving catenaries, varying at most two parameters.
Kosovo: The development of interest groups in a fragile democracy
Authors: Krasniqi Naile
Published: March 2019

Kosovo offers a unique opportunity to study interest groups in both a transitional political system and a new country. As the youngest of the Balkan countries, both its pluralist democracy and its interest group system are in the early stages of development. The most significant influence on this development was Kosovo's grueling fight for independence from Serbia in the 1990s. This produced a particular form of interest and interest group activity quite different from most political systems in transition to democracy. As in all such systems, however, Kosovo's group system has also been shaped by its political culture, socioeconomic, including religious, factors, and particularly the international community. This article explains the various factors that shaped early interest group activity, its characteristics, and how it has evolved into a more traditional group system but one that remains bifurcated.
Effect of aromatic substitution on the cure reaction and network properties of anhydride cured triphenyl ether tetraglycidyl epoxy resins
Authors: Varley Russell J. , Dao Buu , Nguyen Tri , Lee Sunglin , Nishino Takashi
Published: March 2019

A systemic study of the impact of aromatic substitution on the reaction rate and network properties of the isomers of a tetraglycidylaniline triphenyl ether epoxy resin cured with anhydride hardeners is presented here. The epoxy resins synthesized in this work were based upon N,N,N,N‐tetraglycidyl bis(aminophenoxy)benzene (TGAPB), where the glycidyl aniline and ether groups change from being all meta (133 TGAPB), to meta and para (134 TGAPB), and finally to an all para substituted epoxy resin (144 TGAPB). Increasing para substitution increased reaction rate, promoted the onset of vitrification and increased epoxide conversion. Thermal properties such as glass transition temperatures (Tg) and coefficients of thermal expansion (CTE) both increased consistently with increasing para substitution, although thermal stability as measured via thermogravimetric analysis decreased. Mechanical properties also varied systematically with flexural strength and ductility increasing with increased para substitution, while the modulus decreased. Indeed, the ductility almost doubled, as measured by the work of fracture and displacement at failure highlighting the importance of substitution on properties.
Time perception and the experience of agency in meditation and hypnosis
Authors: Lush Peter , Dienes Zoltan
Published: March 2019

Mindfulness meditation and hypnosis are related in opposing ways to awareness of intentions. The cold control theory of hypnosis proposes that hypnotic responding involves the experience of involuntariness while performing an actually intentional action. Hypnosis therefore relies upon inaccurate metacognition about intentional actions and experiences. Mindfulness meditation centrally involves awareness of intentions and is associated with improved metacognitive access to intentions. Therefore, mindfulness meditators and highly hypnotizable people may lie at opposite ends of a spectrum with regard to metacognitive access to intention‐related information. Here we review the theoretical background and evidence for differences in the metacognition of intentions in these groups, as revealed by chronometric measures of the awareness of voluntary action: the timing of an intention to move (Libet's “W” judgments) and the compressed perception of time between an intentional action and its outcome (“intentional binding”). We review these measures and critically evaluate their proposed connection to the experience of volition and sense of agency.
Structural insights on P31‐43, a gliadin peptide able to promote an innate but not an adaptive response in celiac disease
Authors: Calvanese Luisa , Nanayakkara Merlin , Aitoro Rosita , Sanseverino Marina , Tornesello Anna Lucia , Falcigno Lucia , D'Auria Gabriella , Barone Maria Vittoria
Published: March 2019

Inflammation of intestinal tissue in patients affected by celiac disease (CD) originates from the adaptive and innate immune responses elicited by the undigested gliadin fragments through molecular mechanisms not yet completely described. Undigested A‐gliadin peptide P31‐43 is central to CD pathogenesis, entering enterocytes in vesicular compartments by endocytosis and inducing an innate immune response in CD intestinal mucosa. This study focused on the reasons why P31‐43 does not behave as adaptive immunogenic agent. Once obtained by NMR analysis, the three‐dimensional model of P31‐43 was used to implement a series of in silico experiments aimed to explore the ability of the peptide to interact with HLA‐DQ2 and the corresponding receptor onto T cells. Our results show that P31‐43 is a poor ligand for DQ2 and/or T‐cell receptor. This study was also aimed to investigate, from a structural point of view, the previous experimental findings by which P31‐43 is able to enhance the phosphorylation level of the protein ERK2, while some P31‐43 Ala‐mutants decrease or totally inhibit that process. The molecular models of P31‐43, P31‐43 P36A, and F37A mutants were used for in silico docking experiments onto the ERK2 structure. The experiments support the hypothesis that P31‐43 F37A works as an ERK2 phosphorylation inhibitor because it binds to the ERK2 phosphorylation site. This study reports on the structural properties of so far never NMR characterized gliadin peptides relevant in CD and explores details about their mechanisms of action.
Interplay of Electron–Electron Scattering with Size‐Effects, Impurities, and Magnetic Fields in Extremely Pure and W‐Doped Molybdenum Single Crystals
Authors: Elefant Dieter
Published: March 2019

The interaction of electron–electron scattering with the size‐effect, with electron–phonon scattering, and with electron‐impurity scattering is measured and interpreted on high‐purity and W‐doped single crystalline molybdenum in the temperature range T = 1.6…30 K. On a set of more than 30 single crystals with different axis orientations the range down to 1 at · ppm impurities was realized, resulting in residual resistance ratios up to RRRimp = 1 × 106 and in electron mean free paths up to λimp = 12 mm. The interference of normal electron–electron scattering (NEES) with the size‐effect (Gurzhi effect, Knudsen effect) is proved in crystals with RRRimp ≥ 100 000. Relaxation times for NEES and electron‐umklapp scattering are estimated. Different types of magnetoresistance (MR) are measured in longitudinal and transverse magnetic fields . An orientation‐independent ωCτ value for Mo is deduced. The size‐effect reduction in longitudinal field is shown to be consistent with the Chambers calculations under consideration of NEES. The high‐field transverse magnetoresistance (TMR) of the high‐purity crystals is dominated by the static skin effect: the surface TMR short circuits the compensation‐induced bulk TMR which is shown to follow over 10 orders of magnitude without any sign of saturation.
Multivariate two‐sample permutation tests for trials with multiple time‐to‐event outcomes
Authors: Persson Inger , Arnroth Lukas , Thulin Måns
Published: March 2019

Clinical trials involving multiple time‐to‐event outcomes are increasingly common. In this paper, permutation tests for testing for group differences in multivariate time‐to‐event data are proposed. Unlike other two‐sample tests for multivariate survival data, the proposed tests attain the nominal type I error rate. A simulation study shows that the proposed tests outperform their competitors when the degree of censored observations is sufficiently high. When the degree of censoring is low, it is seen that naive tests such as Hotelling'sT2outperform tests tailored to survival data. Computational and practical aspects of the proposed tests are discussed, and their use is illustrated by analyses of three publicly available datasets. Implementations of the proposed tests are available in an accompanying R package.
The stream evolution triangle: Integrating geology, hydrology, and biology
Authors: Castro Janine M. , Thorne Colin R.
Published: March 2019

The foundations of river restoration science rest comfortably in the fields of geology, hydrology, and engineering, and yet, the impetus for many, if not most, stream restoration projects is biological recovery. Although Lane's stream balance equation from the mid‐1950s captured the dynamic equilibrium between the amount of stream flow, the slope of the channel, and the amount and calibre of sediment, it completely ignored biology. Similarly, most of the stream classification systems used in river restoration design today do not explicitly include biology as a primary driver of stream form and process. To address this omission, we cast biology as an equal partner with geology and hydrology, forming a triumvirate that governs stream morphology and evolution. To represent this, we have created the stream evolution triangle, a conceptual model that explicitly accounts for the influences of geology, hydrology, and biology. Recognition of biology as a driver leads to improved understanding of reach‐scale morphology and the dynamic response mechanisms responsible for stream evolution and adjustment following natural or anthropogenic disturbance, including stream restoration. Our aim in creating the stream evolution triangle is not to exclude or supersede existing stream classifications and evolutionary models but to provide a broader “thinking space” within which they can be framed and reconsidered, thus facilitating thought outside of the alluvial box.
D‐optimal designs for multiarm trials with dropouts
Authors: Lee Kim May , Biedermann Stefanie , Mitra Robin
Published: March 2019

Multiarm trials with follow‐up on participants are commonly implemented to assess treatment effects on a population over the course of the studies. Dropout is an unavoidable issue especially when the duration of the multiarm study is long. Its impact is often ignored at the design stage, which may lead to less accurate statistical conclusions. We develop an optimal design framework for trials with repeated measurements, which takes potential dropouts into account, and we provide designs for linear mixed models where the presence of dropouts is noninformative and dependent on design variables. Our framework is illustrated through redesigning a clinical trial on Alzheimer's disease, whereby the benefits of our designs compared with standard designs are demonstrated through simulations.
Biomimetic Design of Hollow Flower‐Like g‐C3N4@PDA Organic Framework Nanospheres for Realizing an Efficient Photoreactivity
Authors: Wang Haihui , Lin Qianying , Yin Litian , Yang Yuling , Qiu Yuan , Lu Chunhua , Yang Huanghao
Published: March 2019

Organic framework polymers have attracted much interest due to the enormous potential design space offered by the atomically precise spatial assembly of organic molecular building blocks. The morphology control of organic frameworks is a complex issue that hinders the development of organic frameworks for practical applications. Biomimetic self‐assembly is a promising approach for designing and fabricating multiple‐functional nanoarchitectures. A bioinspired hollow flower‐like organic framework nanosphere heterostructure comprised of carbon nitride and polydopamine (g‐C3N4@PDA) is successfully synthesized via a mild and green method. This heterostructure can effectively avoid the agglomeration of nanosheets to better access the hollow nanospheres with high open‐up specific surface area. The electron delocalization of g‐C3N4 and PDA under visible light can largely promote photoelectron transfer and enhance the photocatalytic activity of the g‐C3N4@PDA. Furthermore, the g‐C3N4@PDA can effectively enhance the generation of reactive oxygen species under irradiation, which can lead to cell apoptosis and enhance the performance for cancer therapy. Therefore, the as‐prepared g‐C3N4@PDA provides a paradigm of highly efficient photocatalyst that can be used as nanomedicine toward cancer therapy. This study could open up a new avenue for exploiting more other potential hollow nanosphere organic frameworks.
High‐Efficient Preparation of Cross‐Linked Cassava Starch by Microwave‐Ultrasound‐Assisted and its Physicochemical Properties
Authors: Sun Jin , He Ri‐Mei , Gao Feng‐Yuan , Kou Zong‐Liang , Lan Li‐Hong , Lan Ping , Liao An‐Ping
Published: March 2019

Cross‐linked cassava starch (CCS) is prepared by a simple method assisted by microwave‐ultrasound using cassava starch as raw material. Several factors affecting cross‐linking reaction such as starch concentration, microwave–ultrasound power ratio, pH, reaction time, and amount of (NaPO3)6 are investigated by orthogonal experiment in terms of sedimentation volume for the CCS and the optimum conditions are established. Under these conditions, the sedimentation volume of the prepared CCS is 3.50. After cross‐linking, the crystallinity measured by X‐ray diffraction (XRD) decreases which is also confirmed by Fourier transform infrared (FTIR) spectroscopy. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) observations indicate that the obtained CCS is in rough spherical with the same average sizes as native starch. Thermogravimetric analysis (TGA) reports CCS exhibit higher thermal stability. In addition, the physicochemical properties of CCS are been studied. It is found that the freeze‐thaw stability, acid resistance, and thermal stability are highly improved, indicating that CCS has high application value in the food industry.
PDGF Signaling in Primitive Endoderm Cell Survival Is Mediated by PI3K-mTOR Through p53-Independent Mechanism
Authors: Bessonnard Sylvain , Vandormael-Pournin Sandrine , Coqueran Sabrina , Cohen-Tannoudji Michel , Artus Jérôme
Published: March 2019

Receptor tyrosine kinase signaling pathways are key regulators for the formation of the primitive endoderm (PrE) and the epiblast (Epi) from the inner cell mass (ICM) of the mouse preimplantation embryo. Among them, FGF signaling is critical for PrE cell specification, whereas PDGF signaling is critical for the survival of committed PrE cells. Here, we investigated possible functional redundancies among FGF, PDGF, and KIT signaling and showed that only PDGF signaling is involved in PrE cell survival. In addition, we analyzed the effectors downstream of PDGFRα. Our results suggest that the role of PDGF signaling in PrE cell survival is mediated through PI3K-mTOR and independently from p53. Lastly, we uncovered a role for PI3K-mTOR signaling in the survival of Epi cells. Taken together, we propose that survival of ICM cell lineages relies on the regulation of PI3K-mTOR signaling through the regulation of multiple signaling pathways. Stem Cells  2019;37:888–898
Numerical/experimental investigations on reducing drag penalty of passive vortex generators on a NACA 4415 airfoil
Authors: Fouatih Omar Madani , Imine Bachir , Medale Marc
Published: March 2019

A study emphasizing the effects of passive vortex generators (VGs) on aerodynamic characteristics of a NACA 4415 airfoil is presented. Both experimental and numerical works have been carried out on an array of VGs attached to a NACA 4415 airfoil. Lift and drag measurements are made at various angles of attack by using three‐axis component balance system. On the numerical side, Reynolds‐averaged Navier‐Stokes (RANS) equations have been solved with ANSYS FLUENT 14.5 commercial code with fully structured mesh and three turbulence models (realizable k‐ε, k‐ω shear stress transport [SST] and the Spalart‐Allmaras model) at Reynolds number Re = 2 × 105. Parametric studies have been conducted to find out optimal configurations with respect to span‐wise separation distance between VGs, along with their location along the chord. A very good agreement has been obtained between experimental and computational results indicating that this optimized configuration is robust for the considered parameters. It turns out that increasing the span‐wise separation length increases the aerodynamic performances (lift‐to‐drag ratio) at low attack angles for which low parasitic drag is achieved but conversely degrades it at higher ones. For the stream‐wise location along the chord, upstream position of VGs degrades the lift‐to‐drag ratio at low attack angles and conversely improves it at higher ones.
A review of international practices for energy efficiency and carbon emissions reduction and lessons learned for China
Authors: Liu Xu , Shen Bo , Price Lynn , Hasanbeigi Ali , Lu Hongyou , Yu Cong , Fu Guanyun
Published: March 2019

China's industrial sector dominates the country's total energy consumption, and improving energy efficiency in that sector is crucial to help China reach its energy and carbon dioxide emissions reduction goals. There are many energy efficiency policies in China, but the motivation and willingness of enterprises to improve energy efficiency has weakened. This article first identifies barriers that enterprises face to be self‐motivated to implement energy efficiency measures and then categorizes these barriers into four categories: awareness, information, technical capacity, and financial availability. It then reviews international policies and programs to improve energy efficiency, and evaluates how these policies have helped to address the barriers identified. We found that policies and programs in energy efficiency and carbon reduction need to go hand in hand to incentivize companies, and that those policies and programs send clearer signals and help change enterprises' decisions when they are persistent but dynamic. Our specific policy recommendations to China fall under three key categories: identification of energy efficiency potential, workforce development, and market channels for energy efficiency financing.

This article is categorized under:

Energy and Climate > Economics and Policy

Energy Efficiency > Economics and Policy

Energy Efficiency > Climate and Environment
Retracted: Acclimation of 2‐chlorophenol‐biodegrading activated sludge and microbial community analysis
Authors: Sun Zhirong , Zhang Jinwei , Yang Jie , Li Jiangyang , Wang Jianguang , Hu Xiang
Published: March 2019

Using glucose as cosubstrate, activated sludge that could effectively biodegrade 40 mg/L 2‐chlorophenol was successfully domesticated in sequencing batch reactors. To acclimate the sludge, 2‐chlorophenol was increased stepwise from 0 to 40 mg/L. High‐throughput sequencing revealed that the microbial community richness increased during the first 5 days of acclimation to 5 mg/L 2‐chlorophenol and then decreased after another 20 days as 2‐chlorophenol was increased. The original sludge obtained from a water resource recovery facility had the highest microbial diversity. As the acclimation continued further, community richness and diversity both increased, but they decreased again, significantly, when 2‐chlorophenol reached 40 mg/L. Saccharibacteria_norank, Bacillus, Saprospiraceae_uncultured, and Lactococcus were the dominant bacteria. Bacillus and Pseudomonas were the main known chlorophenol‐degrading bacteria. WCHB1‐60_norank, Tetrasphaera, Comamonadaceae_unclassified, and Haliangium showed poor tolerance to 2‐chlorophenol. Higher bacterial tolerance to chlorophenols does not mean higher degrading capability. The degradation of chlorophenols was not positively correlated with the detected abundance of known 2‐chlorophenol‐degrading bacteria.

Practitioner points

Activated sludge that could effectively biodegrade 40 mg/L 2‐chlorophenol was successfully domesticated using glucose as cosubstrate in sequencing batch reactors.

Saccharibacteria_norank, Bacillus, Saprospiraceae_uncultured, and Lactococcus were the dominant bacteria. Bacillus and Pseudomonas were the main known chlorophenol‐degrading bacteria detected in this study.

The degrading capability and tolerance of bacteria to chlorophenols were relatively independent and the degradation of chlorophenols may be the synergistic effect of various bacteria.
Compensation and Amplification of Attenuation Bias in Causal Effect Estimates
Authors: Sengewald Marie-Ann , Pohl Steffi
Published: March 2019

Covariate-adjusted treatment effects are commonly estimated in non-randomized studies. It has been shown that measurement error in covariates can bias treatment effect estimates when not appropriately accounted for. So far, these delineations primarily assumed a true data generating model that included just one single covariate. It is, however, more plausible that the true model consists of more than one covariate. We evaluate when a further covariate may reduce bias due to measurement error in another covariate and in which cases it is not recommended to include a further covariate. We analytically derive the amount of bias related to the fallible covariate’s reliability and systematically disentangle bias compensation and amplification due to an additional covariate. With a fallible covariate, it is not always beneficial to include an additional covariate for adjustment, as the additional covariate can extensively increase the bias. The mechanisms for an increased bias due to an additional covariate can be complex, even in a simple setting of just two covariates. A high reliability of the fallible covariate or a high correlation between the covariates cannot in general prevent from substantial bias. We show distorting effects of a fallible covariate in an empirical example and discuss adjustment for latent covariates as a possible solution.
It's Not Just What You Say, But How You Say It: The Effect of Language Style Matching on Perceived Quality of Consumer Reviews
Authors: Liu Angela Xia , Xie Ying , Zhang Jurui
Published: March 2019

This study explores the role of language style in the perceived quality of online reviews. Drawing from research in psychology and sociology, we posit that language style matching (LSM) of a review—the degree to which the language style of a review matches the language style of intended customers—directly influences the perceived quality of the review. We also propose that LSM should matter more when processing fluency is greatly needed such as when customers learn about new products and process complicated product information. Using restaurant reviews from Yelp, we calculate the LSM score for every review to measure the distance between the language style of the focal review and the typical language style of the restaurant's intended customers. We find that LSM has a significant and positive effect on the number of useful votes received by a review. In addition, the effect of LSM is more pronounced for less familiar restaurants and for more complicated reviews. We discuss the implications of these findings for online review platforms, restaurant managers, and online review writers and close by identifying several opportunities for further research.
Additive manufacturing of tantalum – A study of chemical and physical properties of printed tantalum
Authors: Sungail Craig , Abid Aamir D.
Published: March 2019

Global Advanced Metals (GAM), a leader for almost 70 years in the production of tantalum and niobium products, has undertaken to study the effect of oxygen on laser printed tantalum parts. Angular tantalum powder of low and high oxygen content was spheroidized via radio-frequency plasma under argon. The particle size distributions (PSD) were controlled before feeding the angular powder and the spherical powder PSD matched that of the feed powder, with no ‘fuzz’ or satellites and good Hall flow. The spherical powder was passivated slowly with oxygen to maintain nearly the same oxygen content as that of the feed angular powders. The samples of high and low oxygen powders were laser printed, under argon, providing tensile bars for stress–strain and microscopic investigations. Low oxygen spherical powder led to parts with higher elongations and ultimate tensile (UTS) and microscopic evidence of ductile fracture.
3115 Barriers and Resources in Career Development in Academic Medicine as Reported by Junior Faculty
Authors: Schweitzer Julie , Rainwater Julie , Giacinto Rebeca , Ton Hendry
Published: March 2019

OBJECTIVES/SPECIFIC AIMS: To identify the most frequently reported barriers/constraints and resources by junior faculty in achieving their goals at a large medical school in the Western United States. METHODS/STUDY POPULATION: We reviewed 222 individual development plans (IDPs) from 26 departments in an academic medical center for content regarding constraints and resources to achieve activities and barriers and/or resources to achieve new goals. The content and quality of the IDPs included was ascertained using quantitative data analysis as well a review of open-ended qualitative questions. In addition to analyzing the content, the quality and percent completion of data filled out for each field in the IDP was also assessed to help identify gaps with departments in successfully completing and submitting their IDPs. RESULTS/ANTICIPATED RESULTS: Junior faculty indicated the following barriers: time/time management (55%); work/life balance (32%); funding (8%) and other (5%). Junior faculty also indicated that they had resources to help them achieve their goals, including: mentors (60%); collaborators (26%); colleagues (6%); other (8%). DISCUSSION/SIGNIFICANCE OF IMPACT: The barriers in goal achievement (e.g., time/time management & work/life balance issues) at this academic medical setting suggest that further resources regarding time management and work - life balance need to be developed and disseminated in order to assist faculty in achieving their objectives. This project also reinforces the importance of having a robust mentor or mentoring team for junior faculty. Mentors and administrators should work collaboratively with junior faculty to identify resources to improve time management and work-life balance.
3143 DIAMOND: A Digital Platform for Workforce Development
Authors: Eakin Brenda , Samuels Elias M. , Ellingrod Vicki , Jones Carolynn , Martina Camille Anne , Peyre Sarah , Rushforth Alice M , Chung Haejung , Perorazio Thomas E
Published: March 2019

OBJECTIVES/SPECIFIC AIMS: The DIAMOND project encourages study team workforce development through the creation of a digital learning space that brings together resources from across the CTSA consortium. This allows for widespread access to and dissemination of training and assessment materials. DIAMOND also includes access to an ePortfolio that encourages CRPs to define career goals and document professional skills and training. METHODS/STUDY POPULATION: Four CTSA institutions (the University of Michigan, the Ohio State University, University of Rochester, and Tufts CTSI) collaborated to develop and implement the DIAMOND portal. The platform is structured around eight competency domains, making it easy for users to search for research training and assessment materials. Contributors can upload links to (and meta-data about) training and assessment materials from their institutions, allowing resources to be widely disseminated through the DIAMOND platform. Detailed information about materials included in DIAMOND is collected through an easy to use submission form. DIAMOND also includes an ePortfolio designed for CRPs. This encourages workforce development by providing a tool for self-assessment of clinical research skills, allowing users to showcase evidence of experience, training and education, and fosters professional connections. RESULTS/ANTICIPATED RESULTS: To date, more than 100 items have been posted to DIAMOND from nine contributors. In the first 30 days there were 229 active users with more than 500 page views from across the U.S. as well as China and India. Training materials were viewed most often from four competency domains: 1) Scientific Concepts & Research Design, 2) Clinical Study Operations, 3) Ethical & Participant Safety, and 4) Leadership & Professionalism. Additionally, over 100 CRPs have created a DIAMOND ePortfolio account, using the platform to document skills, connect with each other, and search for internships and job opportunities. DISCUSSION/SIGNIFICANCE OF IMPACT: Lessons learned during development of the DIAMOND digital platform include defining relevant information to collect for the best user experience; selection of a standardized, user-friendly digital platform; and integration of the digital network and ePortfolio. Combined, the DIAMOND portal and ePortfolio provide a professional development platform for clinical research professionals to contribute, access, and benefit from training and assessment opportunities relevant to workforce development and their individual career development needs.
3149 Embedding Implementation Science Within a Translational Health Sciences PhD: Educating Future Scientists to Bridge the Gap Between Research, Practice and Policy
Authors: Corcoran Mary , McDonald Paige , van der Wees Philip , Schlumpf Karen , Weaver Jennifer
Published: March 2019

OBJECTIVES/SPECIFIC AIMS: Determine the effectiveness of a curriculum designed to teach doctoral students to use implementation science theories, models and frameworks in optimizing scientific, social, political, cultural and organizational impact METHODS/STUDY POPULATION: Analysis of Integrated Final Projects across three cohorts of doctoral students (N=30) to identify sub-disciplinary knowledge integration and application. RESULTS/ANTICIPATED RESULTS: Integrated Final Projects indicate that the integration of IS, Program Theory and Research design within semester two yields application of integrated, sub-disciplinary knowledge to research design, identification of mechanisms of action and the address of barriers and facilitators to implementation of findings. Future analysis will be conducted to determine the degree to which dissertations reflect a similar level of sub-disciplinary integration and focus on implementation within the appropriate service setting. DISCUSSION/SIGNIFICANCE OF IMPACT: Training future translational researchers to understand and use implementation science theories, models and frameworks can potentially result in narrowing the science-to-service gap.