bluuebunny/crossref_metadata_2025 huggingface dataset:
A three‐dimensional perspective of Daphnia’s swimming behavior with and without predator cues
Authors: Langer Sina M. , Weiss Linda C. , Ekvall Mikael T. , Bianco Giuseppe , Hansson Lars‐Anders , Tollrian Ralph
Published: February 2019

Behavioral adaptations play an important role in predator–prey interactions as they reduce predation risk. Prey organisms have therefore evolved a tremendous variability in behavioral adaptations. In case of small crustaceans of the genus Daphnia, which are common and important herbivores transferring energy from primary producers to higher trophic levels, such as predatory fish, and insects, altered migration patterns, swarming, or adaptive swimming speeds may increase survival rates. However, hitherto it has been difficult to analyze predator‐induced behavioral adaptations as the small body size, as well as the low contrast between the transparent animals and their environment, most often impede behavioral movement analysis of individual animals. Therefore, we worked with a newly established technique providing higher contrast. We tagged daphniids with fluorescent nanoparticles and used a three‐dimensional movement analysis system. We analyzed behavioral defense strategies of Daphnia clones from three species against different types of predators by measuring their behavior in presence and absence of predator cues. We analyzed swimming speed, depth selection, and motion patterns of Daphnia, as well as swarming behavior. We observed differences in the general swimming behavior in all analyzed aspects and show that daphniids change their behavioral strategies in the presence of predator cues, e.g., decrease their swimming speed as well as their vertical position or increase their nearest neighbor distance. Based on the observed changes in behavioral patterns, we conclude that the swimming behavior of daphniids may play an important role as inducible defense strategy that has the potential to improve prey survival chances.
Multi‐Responsive Bilayer Hydrogel Actuators with Programmable and Precisely Tunable Motions
Authors: Wang Xiaojie , Huang Heqin , Liu Huan , Rehfeldt Florian , Wang Xiaohui , Zhang Kai
Published: February 2019

Multi‐responsive hydrogel actuators show promising applications for soft robotics, biomedical engineering, and artificial muscles, but the uncontrollable nature of their motions poses a barrier to practical applications. Herein, a novel type of bilayer hydrogel actuators (BHAs) is presented comprising of a poly(N‐isopropylacrylamide) (PNIPAm) and a poly (N‐hydroxyethyl acrylamide) (PHEAm) hydrogel layer with various compositions, which demonstrate thermal‐responsive and novel solvent‐responsive actuation under water or within solvents. These BHAs exhibit a wide range of regulable bidirectional motions due to the simultaneous co‐nonsolvency property of PNIPAm and the shrinking behavior of PHEAm in ethanol/water mixtures with various ethanol contents. By adjusting the compositions of ethanol/water mixtures, the bending directions and amplitudes of BHAs are precisely regulable and the curvatures of actuators are tunable between −0.34 and 0.3. Because of the temperature‐responsive character of PNIPAm, BHAs fulfilled thermal‐driven motions to lift items. By reinforcing PHEAm layers with cellulose nanocrystals (CNCs) or CNCs bearing methacylamide moieties on the surface, the weight‐lifting capability of BHAs is highly improved to 18 times the weight of their own polymer weights. This design concept with bilayer structures provides a new strategy for the construction of precisely regulable hydrogel actuators, which allows using solvents to exactly control their motions.
Dysregulations of sonic hedgehog signaling in MED12‐related X‐linked intellectual disability disorders
Authors: Srivastava Siddharth , Niranjan Tejasvi , May Melanie M. , Tarpey Patrick , Allen William , Hackett Anna , Jouk Pierre‐Simon , Raymond Lucy , Briault Slyvain , Skinner Cindy , Toutain Annick , Gecz Jozef , Heath William , Stevenson Roger E. , Schwartz Charles E. , Wang Tao
Published: February 2019

Background

Mutations in mediator of RNA polymerase II transcription subunit 12 homolog (MED12, OMIM 300188) cause X‐linked intellectual disability (XLID) disorders including FG, Lujan, and Ohdo syndromes. The Gli3‐dependent Sonic Hedgehog (SHH) signaling pathway has been implicated in the original FG syndrome and Lujan syndrome. How are SHH‐signaling defects related to the complex clinical phenotype of MED12‐associated XLID syndromes are not fully understood.

Methods

Quantitative RT‐PCR was used to study expression levels of three SHH‐signaling genes in lymophoblast cell lines carrying four MED12 mutations from four unrelated XLID families. Genotype and phenotype correlation studies were performed on these mutations.

Results

Three newly identified and one novel MED12 mutations in six affected males from four unrelated XLID families were studied. Three mutations (c.2692A>G; p.N898D, c.3640C>T; p.R1214C, and c.3884G>A; p.R1295H) are located in the LS domain and one (c.617G>A; p.R206Q) is in the L domain of MED12. These mutations involve highly conserved amino acid residues and segregate with ID and related congenital malformations in respective probands families. Patients with the LS‐domain mutations share many features of FG syndrome and some features of Lujan syndrome. The patient with the L‐domain mutation presented with ID and predominant neuropsychiatric features but little dysmorphic features of either FG or Lujan syndrome. Transcript levels of three Gli3‐dependent SHH‐signaling genes, CREB5, BMP4, and NEUROG2, were determined by quantitative RT‐PCR and found to be significantly elevated in lymphoblasts from patients with three mutations in the MED12‐LS domain.

Conclusions

These results support a critical role of MED12 in regulating Gli3‐dependent SHH signaling and in developing ID and related congenital malformations in XLID syndromes. Differences in the expression profile of SHH‐signaling genes potentially contribute to variability in clinical phenotypes in patients with MED12‐related XLID disorders.
Diffusion tensor distribution imaging
Authors: Topgaard Daniel
Published: February 2019

Conventional diffusion MRI yields voxel‐averaged parameters that suffer from ambiguities for heterogeneous anisotropic materials such as brain tissue. Using principles from solid‐state NMR spectroscopy, we have previously introduced the shape of the diffusion encoding tensor as a separate acquisition dimension that disentangles isotropic and anisotropic contributions to the observed diffusivities, thereby allowing for unconstrained data inversion into diffusion tensor distributions with “size,” “shape,” and orientation dimensions. Here we combine our recent non‐parametric data inversion algorithm and data acquisition protocol with an imaging pulse sequence to demonstrate spatial mapping of diffusion tensor distributions using a previously developed composite phantom with multiple isotropic and anisotropic components. We propose a compact format for visualizing two‐dimensional arrays of the distributions, new scalar parameters quantifying intra‐voxel heterogeneity, and a binning procedure giving maps of all relevant parameters for each of the components resolved in the multidimensional distribution space.
Practitioner Knowledge, Personal Values, and Work Setting Influence Registered Dietitians’ Feeding Tube Recommendations for Patients With Advanced Dementia
Authors: Douglas Joy W. , Lawrence Jeannine C. , Turner Lori W. , Knol Linda L. , Ellis Amy C.
Published: February 2019

Background

Current guidelines discourage tube‐feeding older adults with advanced dementia (AD), as this practice does not improve nutrition status or survival and decreases quality of life in these patients. Because registered dietitians (RDs) often provide feeding recommendations for patients with AD, this study aimed to identify factors that influenced RDs’ feeding tube recommendations for older adults with AD.

Methods

A random sample of RDs who work with older adults in the United States completed a validated, electronic survey. Logistic regression analysis was used to identify factors related to the likelihood of RDs recommending a feeding tube for patients with AD. Independent variables included participant demographics and the 6 subscales of the Attitudes Toward Tube‐Feeding in Advanced Dementia Questionnaire, which measured individual and environmental influences on RDs’ recommendations.

Results

Among the 662 RDs who responded, 72.2% were unlikely to recommend a feeding tube in patients with AD, and 15.4% were likely to do so (with the remaining being “neutral”). Factors associated with avoiding recommending a feeding tube include significantly higher total knowledge [odds ratio (OR) = 1.47, 95% CI (1.30, 1.66)] and personal values scores [OR = 7.51, 95% CI (3.96, 14.24)] and employment in long‐term care settings [OR 3.29, 95% CI (1.38, 7.80)].

Conclusion

In this survey, most RDs were likely to make recommendations that are consistent with current guidelines for tube feeding patients with AD. RDs who work outside the long‐term care setting may benefit from additional training. Future research is needed to understand how personal values may influence recommendations.
Malignant melanoma incidence among children and adolescents in Texas and SEER 13, 1995–2013
Authors: Danysh Heather E. , Navai Shoba A. , Scheurer Michael E. , Hunt Raegan , Venkatramani Rajkumar
Published: February 2019

Background

Epidemiological knowledge and predictors of melanoma among children and adolescents in multiethnic populations are limited.

Procedure

Using data from the Texas Cancer Registry (TCR) and the Surveillance, Epidemiology, and End Results (SEER) 13 database, we identified incident melanoma cases diagnosed at 0–20 years old during 1995–2013 in Texas and the United States, respectively. Using negative binomial regression, associations between demographic factors and melanoma incidence rates (IR) were evaluated by calculating incidence rate ratios (IRR) and 95% confidence intervals (CI). Annual percent change in IRs was assessed with joinpoint regression.

Results

Overall, the melanoma IR was 4.16 (TCR, n = 634) and 4.84 (SEER, n = 1260) per million. Females, adolescents, non‐Hispanic (NH) whites, and Hispanics had higher IRs compared with other groups (P < 0.05). In adjusted analyses, Hispanics had a higher incidence of melanoma than NH non‐whites (Texas IRR = 2.17; 95% CI, 1.30–3.61; SEER IRR = 2.88; 95% CI, 1.97–4.21). In Texas, NH whites with melanoma were more likely to live in low poverty areas, whereas the opposite trend was observed in Hispanics. Melanoma IRs increased throughout 1995–2004 followed by an average annual decrease of 7.6% (95% CI, −12.6%, −2.2%) in Texas and 6.0% (95% CI, −8.5%, −3.4%) in SEER during 2005–2013 (P < 0.05). However, these decreasing trends were not observed among Hispanics or those <10 years old.

Conclusion

Although the overall melanoma IR in children and adolescents appears to be decreasing, this trend is not evident among Hispanics and young children, implicating the need for further research investigating the etiologies and risk factors in these groups.
Hydroxyurea use in young infants with sickle cell disease
Authors: Schuchard Sarah B. , Lissick Jennifer R. , Nickel Amanda , Watson David , Moquist Kristin L. , Blaylark Rae M. , Nelson Stephen C.
Published: February 2019

Background

Hydroxyurea (HU) reduces complications and improves quality and duration of life in sickle cell disease. Evidence supports the use of HU starting after nine months of age.

Procedures

We performed a retrospective study of patients starting HU at less than five years of age between January 1, 2008, and December 31, 2016. We evaluated clinical events, laboratory data, and toxicity between three different age groups: cohort 1 (0–1 year), cohort 2 (1–2 years), and cohort 3 (2–5 years).

Results

Sixty‐five patients were included in the analysis. The mean age was 7.2 months (n = 35), 19.5 months (n = 13), and 35.5 months (n = 17) for cohorts 1, 2, and 3, respectively. Cohort 1 had higher hemoglobin (P = 0.0003) and MCV (P = 0.0199) and lower absolute reticulocyte count (P = 0.0304) at 24 months of age compared with cohort 3. The absolute neutrophil count (ANC) was lower compared with both older cohorts (P = 0.0364, 0.0025). The mean baseline hemoglobin F in cohort 1 was 31.5% compared with 19.7% and 16.5% in cohorts 2 and 3, respectively (P = 0.002, P < 0.0001). The mean duration of therapy was 31.3 months, 57.6 months (P = 0.018), and 29.1 months (P = 0.401), respectively. Mean Hb F levels remained higher in cohort 1 (29.9%) compared with cohorts 2 and 3 (20.4%, P = 0.007; 20.6%, P = 0.003). Cohort 1 experienced fewer hospitalizations (P = 0.0025), pain crises (P = 0.0618), and transfusions (P = 0.0426). There was no difference in toxicity between groups.

Conclusion

HU is safe and effective in patients 5 to 12 months of age and generated a more robust response compared with initiation in older patients.
The uptake of pan‐ethnic expanded carrier screening is higher when offered during preconception or early prenatal genetic counseling
Authors: Larsen Dana , Ma Jingmei , Strassberg Melissa , Ramakrishnan Rajesh , Van den Veyver Ignatia B.
Published: February 2019

Objective

To examine factors that influence uptake of expanded carrier screening (ECS) among women undergoing preconception and prenatal genetic counseling.

Methods

We retrospectively reviewed 500 medical records from women with prenatal or preconception genetic counseling at a prenatal genetic counseling service. We tabulated acceptance of ECS by indication for genetic counseling along with demographic and pregnancy‐related factors.

Results

ECS was offered to 483 of 500 women, and 192 (39.8%) accepted. Of the 67 women counseled preconceptionally, 46 (68.7%) accepted ECS. This was significantly more than for 416 women counseled during pregnancy, of whom 146 (35.1%) accepted (P ≤ 0.001). For pregnant patients, the mean gestational age of those accepting ECS (12 weeks 3 days; n = 146) was significantly lower than those declining (13 weeks 4 days; n = 270; P ≤ 0.001). The acceptance rates were 7 of 12 (58.3%, P = 0.195) for Ashkenazi Jewish women, 12 of 41 (29.3%; P = 0.186) for Asian women, and 7 of 25 (28.0%; P = 0.241) for women of mixed ethnicity.

Conclusions

These results suggest that receiving genetic counseling prior to or earlier in the first trimester is associated with acceptance of ECS and support the importance of early genetic counseling about carrier screening options.
Peptide with endothelial cell affinity and antiplatelet adhesion property to improve hemocompatibility of blood‐contacting biomaterials
Authors: Munisso Maria Chiara , Yamaoka Tetsuji
Published: February 2019

Clinical applications of various blood‐contacting biomaterials have been limited by the complications associated with hemolysis and coagulation on material surfaces. We have been developing anticoagulant‐free polymeric mechanical heart valves with an expanded polytetrafluoroethylene (ePTFE) sewing cuff and have found that the insufficient hemocompatibility of ePTFE is one of the biggest problems to be overcome for their durability. In this work, we present a set of novel peptide sequences that bind selectively to endothelial cells (ECs) and have low platelet activation properties. Five 7mer‐oligopeptides selected from a phage display library were immobilized onto the ePTFE surface by a simple manufacturing protocol and evaluated in vitro. All sequences displayed a better EC‐binding property than the REDV. Two of the peptides displayed extremely low platelet adhesion and activation. In particular, HGGVRLY displayed the highest EC affinity and maximally reduced platelet adhesion. HGGVRLY is a promising peptide for modifying various types of blood‐contacting biomaterials.
Eumelanin for nature‐inspired UV‐absorption enhancement of plastics
Authors: Di Mauro Eduardo , Camaggi Matteo , Vandooren Nils , Bayard Caleb , De Angelis Jordan , Pezzella Alessandro , Baloukas Bill , Silverwood Richard , Ajji Abdellah , Pellerin Christian , Santato Clara
Published: February 2019

In the human body, the black‐brown biopigment eumelanin blocks harmful ultraviolet (UV) radiation. In the plastics industry, additives are often added to polymers to increase their UV‐absorption properties. We herein report an assessment of the biopigment eumelanin as a nature‐inspired additive for plastics to enhance their UV absorption. Since eumelanin is produced by natural sources and is nontoxic, it is an interesting candidate in the field of sustainable plastic additives. In this work, the eumelanin‐containing films of commercial ethylene–vinyl acetate copolymer, a plastic used for packaging applications, were obtained by melt compounding and compression molding. The biopigment dispersion in the films was improved by means of the melanin free acid treatment. It was observed that eumelanin amounts as low as 0.8 wt% caused an increase of the UV absorption, up to one order of magnitude in the UVA range. We also evaluated the effect of eumelanin on the thermal stability and photostability of the films: the biopigment proved to be double‐edged, working both as UV‐absorption enhancer and photo‐prooxidant, as thermogravimetric analysis and infrared spectroscopy revealed. © 2019 Society of Chemical Industry
Should There Be A Part II ABPMR Examination?: A Psychometric Inquiry
Authors: Chiodo Anthony , Raddatz Mikaela , Driscoll Sherilyn W. , Sliwa James A. , Clark Gary S. , Robinson Lawrence R.
Published: February 2019

Background

Certification by the American Board of Physical Medicine and Rehabilitation (ABPMR) requires passing both a written multiple choice examination (Part I) and an oral examination (Part II), but it has been unclear whether the two examinations measure the same or different dimensions of knowledge.

Objective

To evaluate the concordance between the Part I and Part II examinations for ABPMR initial certification with regard to candidate performance on the examinations and their subsets. Our question is whether the Part II examination provides additional assessment of a candidate beyond what Part I provides.

Design

Retrospective psychometric evaluation of deidentified board examination scores.

Setting

ABPMR database of Part I and Part II examination scores.

Participants

Candidates for the ABPMR Part I and Part II examinations after 2005, with a more detailed analysis of candidates for the Part I examination from 2014 to 2016. Examination scores of candidates who took the Part II examination both before and after the examination was standardized in 2005 were also used for an additional analysis.

Methods

Correlations, simple linear regressions, and principal components analysis.

Main Outcome Measurements

Correlation coefficients, variance analysis, and unexplained variance in the principal components analysis.

Results

There is a weak to moderate correlation between performance on the Part I and Part II examinations: r = 0.33, P < .001. There is an additional dimension of assessment that is demonstrated on the Part II examination, with this being primarily in the domains of systems‐based practice and interpersonal communication skills.

Conclusion

The Part I and Part II examinations, although with some overlap, contribute different and meaningful components to the overall evaluation of candidates for board certification in PM&R.

Level of Evidence

III.
Joint Hypermobility among Female Patients Presenting with Chronic Myofascial Pelvic Pain
Authors: Hastings Julie , Forster Jeri E. , Witzeman Kathryn
Published: February 2019

Background

Female chronic pelvic pain is estimated to affect up to 24% of adult women, many of whom have a component of myofascial pelvic pain. Although an association of joint hypermobility and pelvic pain has been hypothesized, limited data are available that estimate the prevalence of joint hypermobility in this population.

Objective

To estimate the prevalence of generalized hypermobility spectrum disorder (G‐HSD) among female patients with chronic myofascial pelvic pain and examine the association between G‐HSD and other frequent pelvic pain‐associated complaints.

Study Design

Retrospective case control.

Setting

Tertiary referral center within a university‐affiliated public health system.

Patients

Adult women who were diagnosed with myofascial pelvic pain during a 1‐year period (n = 77 with G‐HSD and n = 241 without G‐HSD).

Methods

Data were abstracted via chart review of patients meeting inclusion criteria.

Outcomes

The primary outcome of this study was the prevalence of G‐HSD among patients with persistent myofascial pelvic pain. Secondary outcomes included the prevalence of dyspareunia, provoked vestibulodynia, stress urinary incontinence, irritable bowel syndrome, hip pain, low back pain, and fibromyalgia in patients with persistent myofascial pelvic pain with and without G‐HSD.

Results

Twenty‐four percent (N = 77; 95% CI: 19.6, 29.4) of myofascial pelvic pain patients also met criteria for G‐HSD. After adjusting for confounders, the odds in favor of having G‐HSD was 3.55 higher (95% CI: 1.50, 8.40) (P = .004) in females with dyspareunia; 7.46 higher (95% CI: 2.41, 23.1) (P < .001) with low back pain; 3.76 higher (95% CI: 1.35, 10.5) (P = .02) with stress urinary incontinence; 4.72 higher (95% CI: 2.00, 11.2) (P < .001) with irritable bowel syndrome; and 3.12 higher (95% CI: 1.36, 7.13) (P = .007) with hip pain. There was no significant association identified between provoked vestibulodynia or fibromyalgia and G‐HSD.

Conclusion

The estimated prevalence of G‐HSD is higher in chronic myofascial pelvic pain patients than in the general population with statistically significant associations with several comorbid conditions. Characterizing these associations is the first step in developing effective, evidence‐based screening recommendations.

Level of Evidence

III
Water depth‐dependent notonectid predatory impacts across larval mosquito ontogeny
Authors: Dalal Arpita , Cuthbert Ross N , Dick Jaimie TA , Gupta Susmita
Published: February 2019

BACKGROUND

Context‐dependencies can modulate the strength of predatory interactions and often remain unquantified. In particular, differences in water depth within aquatic systems could influence predator efficiencies towards prey which utilise three‐dimensional space through the water column. Differences in prey size could drive prey size–refuge effects, influencing the efficacy of natural enemies towards vector species. We thus quantify the predatory impact of two notonectid predators,Anisops breddiniandAnisops sardeus, towards four different larval instars ofCulex quinquefasciatusprey across a water depth gradient, using functional responses (FRs).

RESULTS

Consumption rates differed significantly between the predators, and interspecific differences in responses to variations in water depth were emergent. Both notonectids were able to handleC. quinquefasciatusprey across all instar stages, yet predation rates were generally higher towards early as opposed to late instar prey.Anisops sardeuswas most voracious, and differential predation rates of this species were most pronounced in shallow waters. Type II FRs were displayed by notonectids in the majority of treatments; however, Type III FRs were emergent in specific treatment groups, with potential implications for prey population stability. Both capture rates and handling times were often greater at greater depths, and thus maximum feeding rates reduced as depth increased. Our results further demonstrate substantial predatory impacts of notonectid predators towards mosquito, and quantify biotic and abiotic context‐dependencies which modulate their impact.

CONCLUSION

Given notonectids are capable of aerial dispersal between ephemeral aquatic habitats of varied volumes, their promotion in aquatic systems could help reduce proliferations of medically important mosquitoes. © 2019 Society of Chemical Industry
Non‐interacting Symmetric Single‐Impurity Anderson Model on a Lattice at Finite Temperatures
Authors: Mahmoud Zakaria M. M. , Gebhard Florian
Published: February 2019

We study the non‐interacting single‐impurity Anderson model (resonant level model) on a lattice at finite temperature as an illustrative example for an exactly solvable quantum‐mechanical problem, and derive the free energy, various thermodynamic potentials (internal energy, entropy, magnetization), and response functions (specific heat, zero‐field magnetic susceptibility). We calculate the magnetic screening cloud, and derive the corresponding correlation length in one dimension beyond which the correlations decay exponentially. The present results remain qualitatively applicable for the interacting single‐impurity Anderson model when the energy scale Г of the resonant‐level model is replaced by the Kondo scale TK.
Electronic and Optoelectronic Applications Based on ReS2
Authors: Xiong Yan , Chen HuaWei , Zhang David Wei , Zhou Peng
Published: February 2019

With continuous research into two‐dimensional transition metal dichalcogenides (TMDs), a great number of high‐performance devices are emerging due to the unique structures and versatile properties of TMDs. As a representative of the group‐VII TMDs, rhenium disulfide (ReS2) has attracted increasing attention because the distorted octahedral crystal structure makes it distinctive from more widely known TMDs members, such as MoS2 and WSe2. It features layer‐independent electrical and anisotropic optical properties which are suitable for the applications of field effect transistors (FETs) and photodetectors. This review focuses on the recent research work about the electronic and optoelectronic applications based on novel 2D ReS2. In the first part, the unique crystal structures and properties are introduced. This is followed by the various preparation methods. Next, high‐performance FETs and photodetectors based on ReS2 are presented. Finally, conclusions are drawn and prospects proposed.
Silibinin protects rat pancreatic β‐cell through up‐regulation of estrogen receptors' signaling against amylin‐ or Aβ1–42‐induced reactive oxygen species/reactive nitrogen species generation
Authors: Yang Jing , Sun Yue , Xu Fanxing , Liu Weiwei , Hayashi Toshihiko , Hattori Shunji , Ushiki‐Kaku Yuko , Onodera Satoshi , Tashiro Shin‐ichi , Ikejima Takashi
Published: February 2019

Amylin and amyloid‐β (Aβ) were found to induce reactive oxygen species (ROS) and reactive nitrogen species (RNS) in rat pancreatic β‐cell line, INS‐1 cells, leading to cell death. In this study, we report on reciprocal relationship between the expression of estrogen receptors (ERs) α and β (ERα and ERβ) and generation of ROS/RNS in amylin/Aβ1–42‐treated INS‐1 cells. That is, pharmacological activation of ERs in INS‐1 cells significantly decreases ROS/RNS generation, but blockage of ERs increases ROS/RNS generation. Silibinin is a natural polyphenolic flavonoid isolated from milk thistle with phytoestrogen activities, also known as silybin. Treatment with silibinin down‐regulated ROS/RNS production induced by treatment with amylin/Aβ1–42 in the cells. Silencing ERs expression with siRNAs targeting ERs showed that the protective effect of silibinin was markedly weakened, indicating that silibinin protection is largely attributed to activation of ERs' signaling. The binding of silibinin to ERs implies that the protective effect of silibinin on amylin/Aβ1–42‐treated INS‐1 cells owes to down‐regulation of ROS/RNS through the activation of ERs phosphorylation. Amylin and Aβ1–42 cotreatment enhanced furthermore ROS/RNS generation and cytotoxicity through further down‐regulation of ERs phosphorylation, and this was reversed by silibinin. Silibinin also protects INS‐1 cells from amylin and Aβ1–42 cotreatment. These results indicate that protective effect of silibinin is mediated by enhancement of ERs phosphorylation that depresses ROS/RNS generation in amylin/Aβ1–42‐treated INS‐1 cells.
Updates of HITRAN spectroscopic database from 2008 to 2016 and implications for near‐infrared radiative transfer calculations
Authors: Menang Kaah P.
Published: February 2019

Spectroscopic information on atmospheric gases, such as absorption line positions, intensities and widths, is important for radiative transfer calculations in climate and weather models. The widely used HIgh resolution TRANsmission (HITRAN) spectroscopic database is updated regularly. A line‐by‐line radiative transfer model has been used to investigate the impacts of the updates of HITRAN from 2008 to 2016 on clear‐sky calculations of absorption and solar heating rates in the near‐infrared region from 4,000 to 10,000 cm−1 (1.0–2.5 µm). These calculations were carried out for the tropical and sub‐arctic atmospheres at solar zenith angles of 30° and 75° using HITRAN absorption line parameters for H2O, CO2, O3, N2O, CO, CH4 and O2 as well as the MT_CKD 2.5 (Mlawer‐Tobin‐Clough‐Kneizys‐Davies) continua for H2O, CO2, O3 and O2. It was found that the improvements in HITRAN absorption line parameters led to modest increases in the spectrally integrated absorbed downward solar fluxes and heating rates. The differences in absorbed fluxes are larger between HITRAN2016 and HITRAN2008 (maximum difference ∼1.3%) than between HITRAN2016 and HITRAN2012 (largest difference ∼0.3%). The corresponding maximum differences in heating rates are less than 2%. In order to improve accuracy, HITRAN2016 should be used in preference to earlier line‐lists for calculating near‐infrared absorbed solar fluxes and heating rates; but for calculations of clear‐sky heating rates in the near‐infrared region that do not require better than 2% accuracy, line parameters from HITRAN2012 and HITRAN2008 may still be used. Although the revisions of HITRAN led to relatively small differences in the spectrally integrated quantities, the improved quality of near‐infrared line parameters will have a significant impact on other atmospheric applications such as the measurements of CO2 concentrations at a precision of less than 1% in Greenhouse Gases Observatory Satellite (GOSAT) and Orbiting Carbon Observatory‐2 (OCO‐2) missions.
The Control of Colloidal Grain Boundaries through Evaporative Vertical Self‐Assembly
Authors: Suh Youngjoon , Pham Quang , Shao Bowen , Won Yoonjin
Published: February 2019

Self‐assembly continuously gains attention as an excellent method to create novel nanoscale structures with a wide range of applications in photonics, optoelectronics, biomedical engineering, and heat transfer applications. However, self‐assembly is governed by a diversity of complex interparticle forces that cause fabricating defectless large scale (>1 cm) colloidal crystals, or opals, to be a daunting challenge. Despite numerous efforts to find an optimal method that offers the perfect colloidal crystal by minimizing defects, it has been difficult to provide physical interpretations that govern the development of defects such as grain boundaries. This study reports the control over grain domains and intentional defect characteristics that develop during evaporative vertical deposition. The degree of particle crystallinity and evaporation conditions is shown to govern the grain domain characteristics, such as shapes and sizes. In particular, the grains fabricated with 300 and 600 nm sphere diameters can be tuned into single‐column structures exceeding ≈1 mm by elevating heating temperature up to 93 °C. The understanding of self‐assembly physics presented in this work will enable the fabrication of novel self‐assembled structures with high periodicity and offer fundamental groundworks for developing large‐scale crack‐free structures.
Gas Sensors Based on Nano/Microstructured Organic Field‐Effect Transistors
Authors: Zhang Shiqi , Zhao Yiwei , Du Xiaowen , Chu Yingli , Zhang Shen , Huang Jia
Published: February 2019

Benefiting from the advantages of organic field‐effect transistors (OFETs), including synthetic versatility of organic molecular design and environmental sensitivity, gas sensors based on OFETs have drawn much attention in recent years. Potential applications focus on the detection of specific gas species such as explosive, toxic gases, or volatile organic compounds (VOCs) that play vital roles in environmental monitoring, industrial manufacturing, smart health care, food security, and national defense. To achieve high sensitivity, selectivity, and ambient stability with rapid response and recovery speed, the regulation and adjustment of the nano/microstructure of the organic semiconductor (OSC) layer has proven to be an effective strategy. Here, the progress of OFET gas sensors with nano/microstructure is selectively presented. Devices based on OSC films one dimensional (1D) single crystal nanowires, nanorods, and nanofibers are introduced. Then, devices based on two dimensional (2D) and ultrathin OSC films, fabricated by methods such as thermal evaporation, dip‐coating, spin‐coating, and solution‐shearing methods are presented, followed by an introduction of porous OFET sensors. Additionally, the applications of nanostructured receptors in OFET sensors are given. Finally, an outlook in view of the current research state is presented and eight further challenges for gas sensors based on OFETs are suggested.
Probing the Active Sites of Carbon‐Encapsulated Cobalt Nanoparticles for Oxygen Reduction
Authors: Yan Xuecheng , Dong Chung‐Li , Huang Yu‐Cheng , Jia Yi , Zhang Longzhou , Shen Shaohua , Chen Jun , Yao Xiangdong
Published: February 2019

Great effort has been contributed to exploring efficient and cost‐effective oxygen reduction reaction (ORR) catalysts for fuel cell applications in the past decades. Now various electrocatalysts can be synthesized for high‐performance ORR catalysis. However, the identification of the ORR active sites in many nonprecious metal‐based catalysts is still difficult. This is due to the heterogeneity and complexity of the catalyst structures. For example, the active site of core–shell ORR electrocatalysts has been a continuously debatable issue, hampering the exploration of new ORR catalysts. Herein, a carbonized Co metal organic framework (Co@C) is used to uncover the ORR active sites in core–shell electrocatalysts. The surface Co particles in the Co@C sample are removed by HCl wash, and the Co cores are removed using an electrochemical activation method. The characterizations reveal that both the samples before and after the electrochemical activation show the existence of single Co species. The corresponding electrocatalysis test results indicate that neither the surface Co particles nor the encapsulated Co cores influence the ORR performance of the samples. It is deduced that the single Co species coordinated with the nitrogen in the carbon layers of the core–shell catalysts are the actual ORR active sites.
“I Couldn't Just Sit There”: Leadership Learning Through Activism
Authors: Elkins Becki , Elkins Jackson
Published: February 2019

This chapter explores the meaning one high school student and parent/educator make of the concepts of identity, leadership, and activism.
Stepan Prokofievich Timoshenko and America
Authors: Elishakoff Isaac
Published: February 2019

In this essay, we describe relationship of S. P. Timoshenko (1878–1972), who is often identified as “the father of American engineering mechanics” with America, where he arrived in 1922 and stayed until 1964. His autobiography appeared in 1963 in Paris in the Russian language; Timoshenko former students and colleagues at Stanford University arranged its translation into English that appeared in 1968 when Timoshenko became 90 years old. The book provides a testimony of the complex relationship that he developed towards America and Americans. Drawing from various documents in addition to his autobiography, this essay discusses in some detail various facets of his relationship. The main goal of this paper is to show that along harsh criticisms towards United States in his autobiographical book, in various documents he expressed positive views about US.
Thermodynamic bootstrap program for integrable QFT’s: form factors and correlation functions at finite energy density
Authors: Cortés Cubero Axel , Panfil Miłosz
Published: February 2019

Abstract

We study the form factors of local operators of integrable QFT’s between states with finite energy density. These states arise, for example, at finite temperature, or from a generalized Gibbs ensemble. We generalize Smirnov’s form factor axioms, formulating them for a set of particle/hole excitations on top of the thermodynamic background, instead of the vacuum. We show that exact form factors can be found as minimal solutions of these new axioms. The thermodynamic form factors can be used to construct correlation functions on thermodynamic states. The expression found for the two-point function is similar to the conjectured LeClair-Mussardo formula, but using the new form factors dressed by the thermodynamic background, and with all singularities properly regularized. We study the different infrared asymptotics of the thermal two-point function, and show there generally exist two different regimes, manifesting massive exponential decay, or effectively gapless behavior at long distances, respectively. As an example, we compute the few-excitations form factors of vertex operators for the sinh-Gordon model.
Bubbling the NHEK
Authors: Heidmann Pierre
Published: February 2019

Abstract

We build the first family of smooth bubbling microstate geometries that are asymptotic to the near-horizon region of extremal five-dimensional Kerr black holes (NHEK). These black holes arise as extremal non-supersymmetric highly-rotating D1-D5- P solutions in type IIB string theory on T4×S1. Our solutions are asymptotically NHEK in the UV and end in the IR with a smooth cap. In the context of the Kerr/CFT correspondence, these bubbling geometries are dual to pure states of the 1+1 dimensional chiral conformal field theory dual to NHEK. Since our solutions have a bubbling structure in the IR, they correspond to an IR phase of broken conformal symmetry, and their existence supports the possibility that all the pure states whose counting gives the Kerr black hole entropy correspond to horizonless bulk configurations.
Coloured coannihilations: dark matter phenomenology meets non-relativistic EFTs
Authors: Biondini S. , Vogl S.
Published: February 2019

Abstract

We investigate the phenomenology of a simplified model with a Majorana fermion as dark matter candidate which interacts with Standard Model quarks via a colourcharged coannihilation partner. Recently it has been realized that non-perturbative dynamics, including the Sommerfeld effect, bound state formation/dissociation and thermal corrections, play an important role in coannihilations with coloured mediators. This calls for a careful analysis of thermal freeze-out and a new look at the experimental signatures expected for a thermal relic. We employ a state of the art calculation of the relic density which makes use of a non-relativistic effective theory framework and calculate the effective annihilation rates by solving a plasma-modified Schrödinger equation. We determine the cosmologically preferred parameter space and confront it with current experimental limits and future prospects for dark matter detection.
Quantum Wilson surfaces and topological interactions
Authors: Chekeres Olga
Published: February 2019

Abstract

We introduce the description of a Wilson surface as a 2-dimensional topological quantum field theory with a 1-dimensional Hilbert space. On a closed surface, the Wilson surface theory defines a topological invariant of the principal G-bundle P → Σ. Interestingly, it can interact topologically with 2-dimensional Yang-Mills and BF theories modifying their partition functions. This gives a new interpretation of the results obtained in [1]. We compute explicitly the partition function of the 2-dimensional Yang-Mills theory interacting with a Wilson surface for the cases G = SU(N)/ℤ
m
, G = Spin(4l)/(ℤ2 ⊕ ℤ2) and obtain a general formula for any compact connected Lie group.
The Universal Geometry of heterotic vacua
Authors: Candelas Philip , de la Ossa Xenia , McOrist Jock , Sisca Roberto
Published: February 2019

Abstract

We consider a family of perturbative heterotic string backgrounds. These are complex threefolds X with c
1 = 0, each with a gauge field solving the Hermitian Yang-Mill’s equations and compatible B and H fields that satisfy the anomaly cancellation conditions. Our perspective is to consider a geometry in which these backgrounds are fibred over a parameter space. If the manifold X has coordinates x, and parameters are denoted by y, then it is natural to consider coordinate transformations

$$ x\to \tilde{x}\left(x,y\right)\kern0.5em \mathrm{and}\kern0.5em y\to \tilde{y}(y) $$

x
→

x
˜

x
y

and

y
→

y
˜

y

. Similarly, gauge transformations of the gauge field and B field also depend on both x and y. In the process of defining deformations of the background fields that are suitably covariant under these transformations, it turns out to be natural to extend the gauge field A to a gauge field

$$ \mathbb{A} $$

A

on the extended (x, y)-space. Similarly, the B, H, and other fields are also extended. The total space of the fibration of the heterotic structures is the Universal Geometry of the title. The extension of gauge fields has been studied in relation to Donaldson theory and monopole moduli spaces. String vacua furnish a richer application of these ideas. One advantage of this point of view is that previously disparate results are unified into a simple tensor formulation. In a previous paper, by three of the present authors, the metric on the moduli space of heterotic theories was derived, correct through

$$ \mathcal{O} $$

O

(α′), and it was shown how this was related to a simple Kähler potential. With the present formalism, we are able to rederive the results of this previously long and involved calculation, in less than a page.
Discovery of novel glycerolated quinazolinones from Streptomyces sp. MBT27
Authors: Machushynets Nataliia V , Wu Changsheng , Elsayed Somayah S , Hankemeier Thomas , van Wezel Gilles P
Published: February 2019

Actinobacteria are a major source of novel bioactive natural products. A challenge in the screening of these microorganisms lies in finding the favorable growth conditions for secondary metabolite production and dereplication of known molecules. Here, we report that Streptomyces sp. MBT27 produces 4-quinazolinone alkaloids in response to elevated levels of glycerol, whereby quinazolinones A (1) and B (2) form a new sub-class of this interesting family of natural products. Global Natural Product Social molecular networking (GNPS) resulted in a quinazolinone-related network that included anthranilic acid (3), anthranilamide (4), 4(3H)-quinazolinone (5), and 2,2-dimethyl-1,2-dihydroquinazolin-4(3H)-one (6). Actinomycins D (7) and X2 (8) were also identified in the extracts of Streptomyces sp. MBT27. The induction of quinazolinone production by glycerol combined with biosynthetic insights provide evidence that glycerol is integrated into the chemical scaffold. The unprecedented 1,4-dioxepane ring, that is spiro-fused into the quinazolinone backbone, is most likely formed by intermolecular etherification of two units of glycerol. Our work underlines the importance of varying the growth conditions for the discovery of novel natural products and for understanding their biosynthesis.
High-power, Joule-class, temporally shaped multi-pass ring laser amplifier with two Nd:glass laser heads
Authors: Guo Jiangtao , Wang Jiangfeng , Wei Hui , Huang Wenfa , Huang Tingrui , Xia Gang , Fan Wei , Lin Zunqi
Published: February 2019

A high-power, Joule-class, nanosecond temporally shaped multi-pass ring laser amplifier system with two neodymium-doped phosphate glass (Nd:glass) laser heads is demonstrated. The laser amplifier system consists of three parts: an all-fiber structure seeder, a diode-pumped Nd:glass regenerative amplifier and a multi-pass ring amplifier, where the thermally induced depolarization of two laser heads is studied experimentally and theoretically. Following the injection of a square pulse with the pulse energy of 0.9 mJ and pulse width of 6 ns, a 0.969-J high-energy laser pulse at 1 Hz was generated, which had the ability to change the waveform arbitrarily, based on the all-fiber structure front end. The experimental results show that the proposed laser system is promising to be adopted in the preamplifier of high-power laser facilities.
Condensates in thin-layer turbulence
Authors: van Kan Adrian , Alexakis Alexandros
Published: February 2019

We examine the steady state of turbulent flows in thin layers using direct numerical simulations. It is shown that when the layer thickness is smaller than a critical height, an inverse cascade arises which leads to the formation of a steady state condensate where most of the energy is concentrated in the largest scale of the system. For layers of thickness smaller than a second critical height, the flow at steady state becomes exactly two-dimensional. The amplitude of the condensate is studied as a function of layer thickness and Reynolds number. Bi-stability and intermittent bursts are found close to the two critical points. The results are interpreted based on a mean-field three-scale model that reproduces some of the basic features of the numerical results.
Resolving the horizontal direction of internal tide generation
Authors: Pollmann Friederike , Nycander Jonas , Eden Carsten , Olbers Dirk
Published: February 2019

The mixing induced by breaking internal gravity waves is an important contributor to the ocean’s energy budget, shaping, inter alia, nutrient supply, water mass transformation and the large-scale overturning circulation. Much of the energy input into the internal wave field is supplied by the conversion of barotropic tides at rough bottom topography, which hence needs to be described realistically in internal gravity wave models and mixing parametrisations based thereon. A new semi-analytical method to describe this internal wave forcing, calculating not only the total conversion but also the direction of this energy flux, is presented. It is based on linear theory for variable stratification and finite depth, that is, it computes the energy flux into the different vertical modes for two-dimensional, subcritical, small-amplitude topography and small tidal excursion. A practical advantage over earlier semi-analytical approaches is that the new one gives a positive definite conversion field. Sensitivity studies using both idealised and realistic topography allow the identification of suitable numerical parameter settings and corroborate the accuracy of the method. This motivates the application to the global ocean in order to better account for the geographical distribution of diapycnal mixing induced by low-mode internal gravity waves, which can propagate over large distances before breaking. The first results highlight the significant differences of energy flux magnitudes with direction, confirming the relevance of this more detailed approach for energetically consistent mixing parametrisations in ocean models. The method used here should be applicable to any physical system that is described by the standard wave equation with a very wide field of sources.