bluuebunny/crossref_metadata_2025 huggingface dataset:
Canonical PRC1 controls sequence-independent propagation of Polycomb-mediated gene silencing
Authors: Moussa Hagar F. , Bsteh Daniel , Yelagandula Ramesh , Pribitzer Carina , Stecher Karin , Bartalska Katarina , Michetti Luca , Wang Jingkui , Zepeda-Martinez Jorge A. , Elling Ulrich , Stuckey Jacob I. , James Lindsey I. , Frye Stephen V. , Bell Oliver
Published: April 2019

Polycomb group (PcG) proteins play critical roles in the epigenetic inheritance of cell fate. The Polycomb Repressive Complexes PRC1 and PRC2 catalyse distinct chromatin modifications to enforce gene silencing, but how transcriptional repression is propagated through mitotic cell divisions remains a key unresolved question. Using reversible tethering of PcG proteins to ectopic sites in mouse embryonic stem cells, here we show that PRC1 can trigger transcriptional repression and Polycomb-dependent chromatin modifications. We find that canonical PRC1 (cPRC1), but not variant PRC1, maintains gene silencing through cell division upon reversal of tethering. Propagation of gene repression is sustained by cis-acting histone modifications, PRC2-mediated H3K27me3 and cPRC1-mediated H2AK119ub1, promoting a sequence-independent feedback mechanism for PcG protein recruitment. Thus, the distinct PRC1 complexes present in vertebrates can differentially regulate epigenetic maintenance of gene silencing, potentially enabling dynamic heritable responses to complex stimuli. Our findings reveal how PcG repression is potentially inherited in vertebrates.
LncRNA EPR controls epithelial proliferation by coordinating Cdkn1a transcription and mRNA decay response to TGF-β
Authors: Rossi Martina , Bucci Gabriele , Rizzotto Dario , Bordo Domenico , Marzi Matteo J. , Puppo Margherita , Flinois Arielle , Spadaro Domenica , Citi Sandra , Emionite Laura , Cilli Michele , Nicassio Francesco , Inga Alberto , Briata Paola , Gherzi Roberto
Published: April 2019

Long noncoding RNAs (lncRNAs) are emerging as regulators of fundamental biological processes. Here we report on the characterization of an intergenic lncRNA expressed in epithelial tissues which we termed EPR (Epithelial cell Program Regulator). EPR is rapidly downregulated by TGF-β and its sustained expression largely reshapes the transcriptome, favors the acquisition of epithelial traits, and reduces cell proliferation in cultured mammary gland cells as well as in an animal model of orthotopic transplantation. EPR generates a small peptide that localizes at epithelial cell junctions but the RNA molecule per se accounts for the vast majority of EPR-induced gene expression changes. Mechanistically, EPR interacts with chromatin and regulates Cdkn1a gene expression by affecting both its transcription and mRNA decay through its association with SMAD3 and the mRNA decay-promoting factor KHSRP, respectively. We propose that EPR enables epithelial cells to control proliferation by modulating waves of gene expression in response to TGF-β.
Quantifying the factors limiting rate performance in battery electrodes
Authors: Tian Ruiyuan , Park Sang-Hoon , King Paul J. , Cunningham Graeme , Coelho João , Nicolosi Valeria , Coleman Jonathan N.
Published: April 2019

One weakness of batteries is the rapid falloff in charge-storage capacity with increasing charge/discharge rate. Rate performance is related to the timescales associated with charge/ionic motion in both electrode and electrolyte. However, no general fittable model exists to link capacity-rate data to electrode/electrolyte properties. Here we demonstrate an equation which can fit capacity versus rate data, outputting three parameters which fully describe rate performance. Most important is the characteristic time associated with charge/discharge which can be linked by a second equation to physical electrode/electrolyte parameters via various rate-limiting processes. We fit these equations to ~200 data sets, deriving parameters such as diffusion coefficients or electrolyte conductivities. It is possible to show which rate-limiting processes are dominant in a given situation, facilitating rational design and cell optimisation. In addition, this model predicts the upper speed limit for lithium/sodium ion batteries, yielding a value that is consistent with the fastest electrodes in the literature.
A tightly-bonded and flexible mesoporous zeolite-cotton hybrid hemostat
Authors: Yu Lisha , Shang Xiaoqiang , Chen Hao , Xiao Liping , Zhu Yihan , Fan Jie
Published: April 2019

Achieving rapid definitive hemostasis is essential to ensure survival of patients with massive bleeding in pre-hospital care. It is however challenging to develop hemostatic agents or dressings that simultaneously deliver a fast, long-lasting and safe treatment of hemorrhage. Here, we integrate meso-/micro-porosity, blood coagulation and stability into a flexible zeolite-cotton hybrid hemostat. We employ an on-site template-free growth route that tightly binds mesoporous single-crystal chabazite zeolite onto the surface of cotton fibers. This hemostatic material maintains high procoagulant activity after water flow treatment. Chabazite particles are firmly anchored onto the cotton surface with < 1% leaching after 10 min of sonication. The as-synthesized hemostatic device has superior hemostatic performance over most other clay or zeolite-based inorganic hemostats, in terms of higher procoagulant activity, minimized loss of active components and better scalability for practical applications (a hemostatic T-shirt is hereby demonstrated as an example).
Stand-off nuclear reactor monitoring with neutron detectors for safeguards and non-proliferation applications
Authors: van der Ende B. M. , Li L. , Godin D. , Sur B.
Published: April 2019

Safeguards measures are employed at nuclear reactor facilities worldwide, to ensure that nuclear material is not diverted from peaceful uses. Typical safeguards measures involve periodic inspections, off-line verification and video surveillance of fuel cycle activities. Real-time verification of the fissile contents via stand-off monitoring can enhance continuity of knowledge for non-traditional reactor types, including research reactors and small modular reactors. Here we demonstrate the feasibility of using large-area neutron detectors for monitoring nuclear reactors at stand-off distances up to 100 m outside reactor shielding, as a potential reactor safeguards tool. Since the neutron yield per unit reactor power depends upon the isotopic composition of the reactor core, declared changes in fissile composition can be verified without accessing the core. The supporting results of experiments conducted at the National Research Universal reactor in Canada, are presented.
800-kyr land temperature variations modulated by vegetation changes on Chinese Loess Plateau
Authors: Lu Hongxuan , Liu Weiguo , Yang Hong , Wang Huanye , Liu Zhonghui , Leng Qin , Sun Youbin , Zhou Weijian , An Zhisheng
Published: April 2019

The complicity of long-term land surface temperature (LST) changes has been under investigated and less understood, hindering our understanding of the history and mechanism of terrestrial climate change. Here, we report the longest (800 thousand years) LSTs based on distributions of soil fossil bacterial glycerol dialkyl glycerol tetraethers preserved in well-dated loess-paleosol sequences at the center of the Chinese Loess Plateau. We have found a previously-unrecognized increasing early and prolonged warming pattern toward the northwestern plateau at the onset of the past seven deglaciations, corresponding to the decrease in vegetation coverage, suggesting underlying surface vegetation or lack of has played an important role in regulating LSTs, superimposed on the fundamental global glacial–interglacial changes. Our results support that LSTs in semi-humid and semi-arid regions with little vegetation will be more sensitive to the anticipated global temperature rise, while improving vegetation coverage would reduce LSTs and thus ecological impacts.
Augmented reality near-eye display using Pancharatnam-Berry phase lenses
Authors: Moon Seokil , Lee Chang-Kun , Nam Seung-Woo , Jang Changwon , Lee Gun-Yeal , Seo Wontaek , Sung Geeyoung , Lee Hong-Seok , Lee Byoungho
Published: April 2019

An augmented reality (AR) near-eye display using Pancharatnam-Berry (PB) phase lenses is proposed. PB phase lenses provide different optical effects depending on the polarization state of the incident light. By exploiting this characteristic, it is possible to manufacture an AR combiner with a small form factor and a large numerical aperture value. The AR combiner adopted in the proposed system operates as a convex lens for right-handed circularly polarized light and operates as transparent glass for left-handed circularly polarized light. By merging this combiner with a transparent screen, such as diffuser-holographic optical elements (DHOEs), it is possible to make an AR near-eye display with a small form factor and a wide field of view. In addition, the proposed AR system compensates the chromatic aberration that occurs in PB phase lens by adopting three-layered DHOEs. The operating principle of the proposed system is covered, and its feasibility is verified with experiments and analysis.
The contribution of washing processes of synthetic clothes to microplastic pollution
Authors: De Falco Francesca , Di Pace Emilia , Cocca Mariacristina , Avella Maurizio
Published: April 2019

Microplastic pollution caused by washing processes of synthetic textiles has recently been assessed as the main source of primary microplastics in the oceans. Therefore, understanding the effective contribution of the washing process of synthetic clothes to this environmental problem, is of great importance. In this study, wash trials at real scale were performed on commercial clothes by using a household washing machine in order to gain reliable data about the release of microplastics, and to identify possible influences of textile characteristics on the release. The wastewater was collected and filtered through subsequent filters with decreasing porosity, and the amount and dimensions of microfibres were determined. Microfibre release was analysed in relation to the nature and characteristics of the washed clothes. Results showed that microfibres released during washing range from 124 to 308 mg for kg of washed fabric depending from the type of washed garment that corresponds to a number of microfibres ranging from 640,000 to 1,500,000. Some textile characteristics, such as the type of fibres constituting the yarns and their twist, influenced the release of microfibres during washing. A great amount of microfibres of cellulosic nature was also released during washing of clothes made with a blend of polyester/cellulose. Finally the most abundant fraction of microfibres shed was retained by filters with pore size of 60 µm, presenting an average length of 360–660 μm and an average diameter of 12–16 μm, indicating dimensions that could pass through wastewater treatment plants and pose a threat for marine organisms.
Development and characterization of a new rat ocular hypertension model induced by intracameral injection of conjunctival fibroblasts
Authors: Nakagawa Ayumi , Sakai Osamu , Tokushige Hideki , Fujishiro Takashi , Aihara Makoto
Published: April 2019

Glaucoma is a chronic optic neuropathy that leads to visual field loss. Elucidating the mechanisms underlying glaucoma is essential for developing new treatments, such as neuroprotective drugs. Various glaucoma models based on the induction of intraocular pressure (IOP) elevation have been established for use in glaucoma studies. However, the time-dependent pathological changes accompanying IOP elevation have not been fully elucidated. In this study, rat conjunctival fibroblasts were injected into the anterior chamber of rat eyes, and IOP elevation was induced for 28 days. Glaucomatous signs such as optic nerve head cupping, retinal thinning, glial activation and apoptotic signaling in the retina were obvious in the cell-injected eyes on the 14th day after injection. The pattern of retinal ganglion cell (RGC) loss differed by the magnitude of IOP elevation. The number of RGCs decreased by 37.5% in eyes with IOP lower than 50 mmHg (Under-50) and by 88.0% in those with IOP higher than 50 mmHg (Over-50) 28 days after cell injection. The RGC counts were correlated with IOP in the Under-50 group but not in the Over-50 group. Our model may contribute to the investigation of pathogenic mechanisms of glaucoma and the development of new glaucoma treatments.
UM171 expands distinct types of myeloid and NK progenitors from human pluripotent stem cells
Authors: Mesquitta Walatta-Tseyon , Wandsnider Matthew , Kang HyunJun , Thomson James , Moskvin Oleg , Suknuntha Kran , Slukvin Igor I.
Published: April 2019

Scaling up blood cell production from hPSCs is critical to advancing hPSC technologies for blood transfusion, immunotherapy, and transplantation. Here we explored the potential of the HSC agonist pyrimido-indole derivative UM171, to expand hematopoietic progenitors (HPs) derived from hPSCs in chemically defined conditions. We revealed that culture of hPSC-HPs in HSC expansion conditions (SFEM with added TPO, SCF, FLT3L, IL3 and IL6) in the presence of UM171 predominantly expanded HPs with a unique CD34+CD41aloCD45+ phenotype that were enriched in granulocytic progenitors (G-CFCs). In contrast, in lymphoid cultures on OP9-DLL4, in the presence of SCF, FLT3L, and IL7, UM171 selectively expanded CD34+CD45+CD7+ lymphoid progenitors with NK cell potential, and increased NK cell output up to 10-fold. These studies should improve our understanding of the effect of UM171 on de novo generated HPs, and facilitate development of protocols for robust granulocyte and lymphoid cell production from hPSCs, for adoptive immunotherapies.
Atomic-scale diffusion rates during growth of thin metal films on weakly-interacting substrates
Authors: Jamnig A. , Sangiovanni D. G. , Abadias G. , Sarakinos K.
Published: April 2019

We use a combined experimental and theoretical approach to study the rates of surface diffusion processes that govern early stages of thin Ag and Cu film morphological evolution on weakly-interacting amorphous carbon substrates. Films are deposited by magnetron sputtering, at temperatures TS between 298 and 413 K, and vapor arrival rates F in the range 0.08 to 5.38 monolayers/s. By employing in situ and real-time sheet-resistance and wafer-curvature measurements, we determine the nominal film thickness Θ at percolation (Θperc) and continuous film formation (Θcont) transition. Subsequently, we use the scaling behavior of Θperc and Θcont as a function of F and Ts, to estimate, experimentally, the temperature-dependent diffusivity on the substrate surface, from which we calculate Ag and Cu surface migration energy barriers $${{\boldsymbol{E}}}_{{\boldsymbol{D}}}^{{\bf{\exp }}}$$

E

D

exp

and attempt frequencies $${{\boldsymbol{\nu }}}_{{\bf{0}}}^{{\bf{\exp }}}$$

ν

0

exp

. By critically comparing $${{\boldsymbol{E}}}_{{\boldsymbol{D}}}^{{\bf{\exp }}}$$

E

D

exp

and $${{\boldsymbol{\nu }}}_{{\bf{0}}}^{{\bf{\exp }}}$$

ν

0

exp

with literature data, as well as with results from our ab initio molecular dynamics simulations for single Ag and Cu adatom diffusion on graphite surfaces, we suggest that: (i) $${{\boldsymbol{E}}}_{{\boldsymbol{D}}}^{{\bf{\exp }}}$$

E

D

exp

and $${{\boldsymbol{\nu }}}_{{\bf{0}}}^{{\bf{\exp }}}$$

ν

0

exp

correspond to diffusion of multiatomic clusters, rather than to diffusion of monomers; and (ii) the mean size of mobile clusters during Ag growth is larger compared to that of Cu. The overall results of this work pave the way for studying growth dynamics in a wide range of technologically-relevant weakly-interacting film/substrate systems—including metals on 2D materials and oxides—which are building blocks in next-generation nanoelectronic, optoelectronic, and catalytic devices.
Role of Weak Materials in Earthquake Rupture Dynamics
Authors: Hirono Tetsuro , Tsuda Kenichi , Kaneki Shunya
Published: April 2019

Weak materials in seismic slip zones are important in studies of earthquake mechanics. For instance, the exceptionally large slip during the 2011 Tohoku-Oki earthquake has been attributed to the presence of smectite in the fault zone. However, weak fault rocks cannot accumulate large amounts of elastic strain, which is thought to counter their ability to enhance seismic rupture. It is well known that if the permeability of a weak fault is low enough to allow friction-induced thermal pressurization of interstitial fluid, the fault strength decreases dramatically. However, whether intrinsic weakness of fault material or thermal pressurization more efficiently produces large slip on faults bearing weak materials has not been determined. To investigate the role of weak materials in earthquake rupture dynamics, we conducted friction experiments and dynamic rupture simulations using pure smectite and pure graphite to represent weak fault materials. Even when we assumed no thermal pressurization, simulated faults in both media were able to trigger large slip because their extremely low friction was insufficient to arrest the inertial motion of rupture propagating along the fault. We used similar rupture simulations to investigate the cause of the huge slip near the trench during the 2011 Tohoku-Oki earthquake and demonstrated that it can be attributed to thermal pressurization, although our findings suggest that the presence of smectite in the plate-boundary fault may also be required.
Genetic risk score has added value over initial clinical grading stage in predicting disease progression in age-related macular degeneration
Authors: Heesterbeek Thomas J. , de Jong Eiko K. , Acar Ilhan E. , Groenewoud Joannes M. M. , Liefers Bart , Sánchez Clara I. , Peto Tunde , Hoyng Carel B. , Pauleikhoff Daniel , Hense Hans W. , den Hollander Anneke I.
Published: April 2019

Several prediction models for progression of age-related macular degeneration (AMD) have been developed, but the added value of using genetic information in those models in addition to clinical characteristics is ambiguous. In this prospective cohort study, we explored the added value of genetics using a genetic risk score (GRS) based on 52 AMD-associated variants, in addition to the clinical severity grading at baseline as quantified by validated drusen detection software, to predict disease progression in 177 AMD patients after 6.5 years follow-up. The GRS was strongly associated with the drusen coverage at baseline (P < 0.001) and both the GRS and drusen coverage were associated with disease progression. When the GRS was added as predictor in addition to the drusen coverage, R2 increased from 0.46 to 0.56. This improvement by the GRS was predominantly seen in patients with a drusen coverage <15%. In patients with a larger drusen coverage, the GRS had less added value to predict progression. Thus, genetic information has added value over clinical characteristics in predicting disease progression in AMD, but only in patients with a less severe disease stage. Patients with a high GRS should be made aware of their risk and could be selected for clinical trials for arresting progression.
Collective Motion as an Ultimate Effect in Crowded Selfish Herds
Authors: Yang Wen-Chi , Schmickl Thomas
Published: April 2019

The selfish herd hypothesis explains how social prey can assemble cohesive groups for maximising individual fitness. However, previous models often abstracted away the physical manifestation of the focal animals such that the influence of getting stuck in a crowded herd on individual adaptation was less intensively investigated. Here, we propose an evolutionary model to simulate the adaptation of egoistic social prey to predation given that individual mobility is strictly restrained by the presence of other conspecifics. In our simulated evolutionary races, agents were set to either be confined by neighbours or move to empty cells on the lattice, and the behavioural traits of those less exposed were selected and inherited. Our analyses show that under this crowded environment, cohesive and steady herds were consistently replaced by morphing and moving aggregates via the attempt of border agents to share predation risk with the inner members. This kind of collective motion emerges purely from the competition among selfish individuals regardless of any group benefit. Our findings reveal that including the crowding effect with the selfish herd scenario permits additional diversity in the predicted outcomes and imply that a wider set of collective animal behaviours are explainable purely by individual-level selection.
Bruch’s Membrane Thickness and Retinal Pigment Epithelium Cell Density in Experimental Axial Elongation
Authors: Dong Li , Shi Xu Han , Kang Yi Kun , Wei Wen Bin , Wang Ya Xing , Xu Xiao Lin , Gao Fei , Jonas Jost B.
Published: April 2019

To assess anatomical changes in eyes with progressive myopia, we morphometrically examined the eyes of guinea pigs with lens-induced axial elongation. Starting at an age of 3–4 weeks, guinea pigs in the experimental group (n = 20 animals) developed unilateral lens-induced axial elongation by wearing goggles for 5 weeks compared to a control group of 20 animals without intervention (axial length:8.91 ± 0.08 mm versus 8.74 ± 0.07 mm; P < 0.001). Five weeks after baseline, the animals were sacrificed, and the eyes enucleated. As measured histomorphometrically, Bruch’s membrane thickness was not significantly correlated with axial length in either group at the ora serrata (P = 0.41), equator (P = 0.41), midpoint between equator and posterior pole (MBEPP) (P = 0.13) or posterior pole (P = 0.89). Retinal pigment epithelium (RPE) cell density decreased with longer axial length at the MBEPP (P = 0.04; regression coefficient beta = −0.33) and posterior pole (P = 0.01; beta = −0.40). Additionally, the thickness of the retina and sclera decreased with longer axial length at the MBEPP (P = 0.01; beta = −0.42 and P < 0.001; beta = −0.64, respectively) and posterior pole (P < 0.001; beta = −0.51 and P < 0.001; beta = −0.45, respectively). Choroidal thickness decreased at the posterior pole (P < 0.001; beta = −0.51). Experimental axial elongation was associated with a thinning of the retina, choroid and sclera and a decrease in RPE cell density, most markedly at the posterior pole. Bruch’s membrane thickness was not related to axial elongation.
Identification and functional prediction of cold-related long non-coding RNA (lncRNA) in grapevine
Authors: Wang Pengfei , Dai Lingmin , Ai Jun , Wang Yongmei , Ren Fengshan
Published: April 2019

Plant long non-coding RNA (lncRNA) undergoes dynamic regulation and acts in developmental and stress regulation. In this study, we surveyed the expression dynamics of lncRNAs in grapevine (Vitis vinifera L.) under cold stress using high-throughput sequencing. Two-hundred and three known lncRNAs were significantly up-regulated and 144 known lncRNAs were significantly down-regulated in cold-treated grapevine. In addition, 2 088 novel lncRNA transcripts were identified in this study, with 284 novel lncRNAs significantly up-regulated and 182 novel lncRNAs significantly down-regulated in cold-treated grapevine. Two-hundred and forty-two differentially expressed grapevine lncRNAs were predicted to target 326 protein-coding genes in a cis-regulatory relationship. Many differentially expressed grapevine lncRNAs targeted stress response-related genes, such as CBF4 transcription factor genes, late embryogenesis abundant protein genes, peroxisome biogenesis protein genes, and WRKY transcription factor genes. Sixty-two differentially expressed grapevine lncRNAs were predicted to target 100 protein-coding genes in a trans-regulatory relationship. The expression of overall target genes in both cis and trans-regulatory relationships were positively related to the expression of lncRNAs in grapevines under cold stress. We identified 31 known lncRNAs as 34 grapevine micro RNA (miRNA) precursors and some miRNAs may be derived from multiple lncRNAs. We found 212 lncRNAs acting as targets of miRNAs in grapevines, involving 150 miRNAs; additionally, 120 grapevine genes were predicted as targets of grapevine miRNAs and lncRNAs. We found one gene cluster that was up-regulated and showed the same expression trend. In this cluster, many genes may be involved in abiotic stress response such as WRKY, Hsf, and NAC transcription factor genes.
Eomes transcription factor is required for the development and differentiation of invariant NKT cells
Authors: Shimizu Kanako , Sato Yusuke , Kawamura Masami , Nakazato Hiroshi , Watanabe Takashi , Ohara Osamu , Fujii Shin-ichiro
Published: April 2019

Eomes regulates the differentiation of CD8+ T cells into effector and memory phases. However, its role in invariant (i)NKT cells remains unknown. Here, we show the impact of Eomes on iNKT cells in the thymus and peripheral tissue using conditional knockout (Eomes-cKO) mice. In the thymus, CD1d-tetramer+CD24+CD44−NK1.1−CD69+stage 0 iNKT cells express higher levels of Eomes than the other iNKT stages. We also found that Eomes regulates NKT1 cell differentiation predominantly. Interestingly, the expression of Eomes in the steady state is low, but can be upregulated after TCR stimulation. We also showed epigenetic changes in the Eomes locus after activation. In addition, vaccination of C57BL/6, but not Eomes-cKO mice with iNKT ligand-loaded dendritic cells generated KLRG1+iNKT cells in lung, characterized as effector memory phenotype by transcriptome profiling. Thus, Eomes regulates not only the differentiation of NKT1 cells in the thymus, but also their differentiation into memory-like KLRG1+iNKT cells in the periphery.
High loading nanoconfinement of V-decorated Mg with 1 nm carbon shells: hydrogen storage properties and catalytic mechanism
Authors: Chen Ming , Hu Miaomiao , Xie Xiubo , Liu Tong
Published: April 2019

A Mg92V8@C nanocomposite with over 94% loading shows high capacity and superb kinetics from the synergetic effects of nanoconfinement and the V catalyst.
Fabrication of superhydrophobic fabrics with outstanding self-healing performance in sunlight
Authors: Zhang Jin , Zhao Jianguo , Qu Wenshan , Wang Zhenxing
Published: April 2019

Superhydrophobic fabrics with an outstanding self-healing performance in sunlight have been prepared by loading all-water-based octadecylamine@polydopamine core–shell nanospheres.
Concisely modularized assembling of graphene-based thin films with promising electrode performance
Authors: Wei Weiwei , Vekariy Rohit L. , You Chuanting , He Yafei , Liu Ping , Wu Dongqing , Zhang Fan
Published: April 2019

Highly dense thin films assembled from cellulose nanofibers and reduced graphene oxide via van der Waals interactions to realize ultrahigh volumetric double-layer capacitances.
Enhanced-performance of self-powered flexible quantum dot photodetectors by a double hole transport layer structure
Authors: Shen Ting , Binks David , Yuan Jifeng , Cao Guozhong , Tian Jianjun
Published: April 2019

Flexible quantum dot photodetectors with large specific detectivity, excellent weak-light responsivity, and outstanding mechanical and electrical stability were successfully fabricated.
Correlation between the translational and rotational diffusion of rod-shaped nanocargo on a lipid membrane revealed by single-particle tracking
Authors: He Liangna , Li Yiliang , Wei Lin , Ye Zhongju , Liu Hua , Xiao Lehui
Published: April 2019

Revealing the diffusion dynamics of nanoparticles on a lipid membrane plays an important role in a better understanding of the cellular translocation process and provides a theoretical basis for the rational design of delivery cargo.
Construction of a luminescent sensor based on a lanthanide complex for the highly efficient detection of methyl parathion
Authors: Hu Xuan , Wang Fengyi , Peng Qianqian , Hu Jing , Peng Huaqiao , Li Lin , Zheng Baozhan , Du Juan , Xiao Dan
Published: April 2019

A lanthanide complex sensor HL–Eu3+ based on an aromatic cyclic polyamine ligand was constructed for MP detection.
Automated glycan assembly of Lewis type I and II oligosaccharide antigens
Authors: Guberman Mónica , Bräutigam Maria , Seeberger Peter H.
Published: April 2019

Lewis antigens are fucosylated oligosaccharides that play crucial roles in various biological processes. Here, we illustrate how automated glycan assembly (AGA) provides quick access to a series of more than ten defined Lewis type-I and type-II antigens.
Multiple local σ-aromaticity of nonagermanide clusters
Authors: Tkachenko Nikolay V. , Boldyrev Alexander I.
Published: April 2019

A new chemical bonding picture of various nonagermanide species were presented. The stability of Ge9 fragments could be well described via the concept of multiple local σ-aromaticity.
Selective decontamination of the reactive air pollutant nitrous acid via node-linker cooperativity in a metal–organic framework
Authors: McGrath Devon T. , Ryan Michaela D. , MacInnis John J. , VandenBoer Trevor C. , Young Cora J. , Katz Michael J.
Published: April 2019

The environmental pollutant nitrous acid is rapidly and selectively sorbed and converted to benign products in the metal–organic framework UiO-66-NH2.
A bimetallic Co4Mo8 cluster built from Mo8 oxothiomolybdate capped by a Co4-thiacalix[4]arene unit: the observation of the Co–Mo synergistic effect for binder-free electrocatalysts
Authors: Zhang Min , Chen Mengwei , Bi Yanfeng , Huang Liangliang , Zhou Kun , Zheng Zhiping
Published: April 2019

Fabricating Co4-thiacalix[4]arene capped Mo8 oxothiomolybdate bimetallic Co4Mo8 nanoclusters on nickel foam serves as efficient binder-free oxygen evolution reaction electrocatalyst with Co–Mo synergistic effect.
B3S monolayer: prediction of a high-performance anode material for lithium-ion batteries
Authors: Jana Saibal , Thomas Siby , Lee Chi Ho , Jun Byeongsun , Lee Sang Uck
Published: April 2019

A high performance B3S monolayer for LIB anode material with high storage capacity, low OCV and low Li diffusion energy barrier.
Degradation of CH3NH3PbI3 perovskite materials by localized charges and its polarity dependency
Authors: Kim Min-cheol , Ahn Namyoung , Lim Eunhak , Jin Young Un , Pikhitsa Peter V. , Heo Jiyoung , Kim Seong Keun , Jung Hyun Suk , Choi Mansoo
Published: April 2019

The breakdown process of CH3NH3PbI3 perovskite crystals by localized charges and its polarity-dependency have been revealed.
In situ incorporation of nanostructured antimony in an N-doped carbon matrix for advanced sodium-ion batteries
Authors: Wu Zhibin , Johannessen Bernt , Zhang Wenchao , Pang Wei Kong , Mao Jianfeng , Liu Hua Kun , Guo Zaiping
Published: April 2019

A one-step and solvent-free pyrolysis method was developed to control the synthesis of an Sb/C composite by structural remolding of liquid Sb.
Thermoelectric transport properties of Ni-, Pd-, and Pt- doped skutterudites with S-filling as charge compensation
Authors: Tu Zhikang , Sun Xin , Li Xin , Li Ruoxi , Xi Lili , Yang Jiong
Published: April 2019

Unlike typical electronegative guest filled skutterudites, which are doped with electron donors at Sb sites to form thermodynamically stable compounds. In this study, substituting at Co sites with Ni, Pd, and Pt atoms instead of at the Sb sites was analyzed. The influence of Ni, Pd, and Pt on the electronic band structure of Ni-, Pd-, and Pt-doped skutterudites was thoroughly analyzed. The degree of band splitting caused by the doping elements was analyzed and shown to be correlated with the strength of anti-bonding between the doping elements and neighboring Sb atoms. The electronic structures in the conduction band minimum (CBM) of the S-filled skutterudites did not undergo a significant change when compared to those of the doped skutterudites. Therefore, the thermoelectric (TE) performance was optimized because of the reduction in the degree of energy band splitting due to the addition of elements ranging from Ni to Pt.
Calibration of the Dermal Advanced REACH Tool (dART) Mechanistic Model
Authors: McNally Kevin , Gorce Jean-Philippe , Goede Henk A , Schinkel Jody , Warren Nick
Published: April 2019

The dermal Advanced REACH Tool (dART) is a Tier 2 exposure modelling tool currently in development for estimating dermal exposure to the hands (mg min−1) for non-volatile liquid and solids-in-liquid products. The dART builds upon the existing ART framework and describes three mass transport processes [deposition (Dhands), direct emission and direct contact (Ehands), and contact transfer (Thands)] that may each contribute to dermal exposure. The mechanistic model that underpins the dART and its applicability domain has already been described in previous work. This paper describes the process of calibrating the mechanistic model such that the dimensionless score that results from encoding contextual information about a task into the determinants of the dART can be converted into a prediction of exposure (mg min−1). Furthermore, as a consequence of calibration, the uncertainty in a dART prediction may be quantified via a confidence interval. Thirty-six experimental studies were identified that satisfied the conditions of: (i) high-quality contextual information that was sufficient to confidently code the dART mechanistic model determinants; (ii) reliable exposure measurement data sets were available. From these studies, 40 exposure scenarios were subsequently developed. A non-linear log-normal mixed-effect model was fitted to the data set of Dhands,   Ehands, and    Thands scores and corresponding measurement data. The dART model was shown to be consistent with activities covering a broad range of tasks [spray applications, activities involving open liquid surfaces (e.g. dipping, mixing), handling of contaminated objects, spreading of liquid products, and transfer of products (e.g. pouring of liquid)]. Exposures resulting from a particular task were each dominated by one or two of the identified mass transport processes. As a consequence of calibration, an estimate of the uncertainty associated with a mechanistic model estimate is available. A 90% multiplicative interval is approximately a factor of six. This represents poorer overall precision than the (inhalation) ART model for dusts and vapours, although better than the ART model for mists. Considering the complexity of the conceptual model compared with the ART, the wide variety of exposure scenarios considered with differing dominant routes, and the particular challenges that result from the consideration of measurement data both above and beneath a protective glove, the precision of the calibrated dART mechanistic model is reasonable for well-documented exposure scenarios coded by experts. However, as the inputs to the model are based upon user judgement, in practical use, the reliability of predictions will be dependent upon both the competence of users and the quality of contextual information available on an exposure scenario.
Delayed onset Takotsubo syndrome following exercise ECG: a case report
Authors: Ghose Aruni , Banerjee Suvro
Published: April 2019

Background

Takotsubo syndrome usually occurs immediately following a physical or emotional trigger. In some cases, a triggering stress may not be evident. A delayed manifestation of the syndrome may account for such cases.

Case summary

An asymptomatic 69-year-old woman presented for a routine cardiac check-up, which revealed normal electrocardiogram (ECG), echocardiography, and exercise ECG. She did not complain of any chest pain during or immediately after the tests. After about 24 h, she developed chest pain for which she was admitted with the provisional diagnosis of acute coronary syndrome. ECG showed dynamic T-wave changes with QTc prolongation. Cardiac biomarkers were mildly elevated. Characteristic reversible left ventricular dysfunction in absence of coronary stenosis ultimately led to the diagnosis of Takotsubo syndrome.

Discussion

Our case represents a delayed occurrence of Takotsubo syndrome triggered by a treadmill exercise stress test, which manifested about 24 h following the stressor. Such delayed manifestation may account for those cases of Takotsubo syndrome where no immediate triggering stressor is evident.
Addressing the Diversity–Validity Dilemma Using Situational Judgment Tests
Authors: Juster Fern R. , Baum Robin Camhi , Zou Christopher , Risucci Don , Ly Anhphan , Reiter Harold , Miller D. Douglas , Dore Kelly L.
Published: April 2019

Purpose

To examine the magnitudes of score differences across different demographic groups for three academic (grade point average [GPA], old Medical College Admission Test [MCAT], and MCAT 2015) and one nonacademic (situational judgment test [SJT]) screening measures and one nonacademic (multiple mini-interview [MMI]) interview measure (analysis 1), and the demographic implications of including an SJT in the screening stage for the pool of applicants who are invited to interview (analysis 2).

Method

The authors ran the analyses using data from New York Medical College School of Medicine applicants from the 2015–2016 admissions cycle. For analysis 1, effect sizes (Cohen d) were calculated for GPA, old MCAT, MCAT 2015, CASPer (an online SJT), and MMI. Comparisons were made across gender, race, ethnicity (African American, Hispanic/Latino), and socioeconomic status (SES). For analysis 2, a series of simulations were conducted to estimate the number of underrepresented in medicine (UIM) applicants who would have been invited to interview with different weightings of GPA, MCAT, and CASPer scores.

Results

A total of 9,096 applicants were included in analysis 1. Group differences were significantly smaller or reversed for CASPer and MMI compared with the academic assessments (MCAT, GPA) across nearly all demographic variables/indicators. The simulations suggested that a higher weighting of CASPer may help increase gender, racial, and ethnic diversity in the interview pool; results for low-SES applicants were mixed.

Conclusions

The inclusion of an SJT in the admissions process has the potential to widen access to medical education for a number of UIM groups.
Co-cultural Communicative Practices of African American Women Seeking Depression Care
Authors: Wardlaw Cassie , Shambley-Ebron Donna
Published: April 2019

African Americans face unique communication challenges when interfacing with the health care system that has a history of discrimination and power differentials. In response to the trifecta of race, class, and gender oppression when seeking health care, African American women make critical decisions regarding how to communicate during the clinical encounter for depression care. The purpose of this study was to use focused ethnography to explore the co-cultural communicative practices that African American women use when seeking depression care. The concept of intersectionality was used to contextualize 5 domains that explained the depth and breadth of African American women's experiences and communication strategies when seeking care for depression.
Semicircumferential Detachment of the Extensor Enthesis For Surgical Treatment of Chronic Lateral Epicondylitis: A Prospective Study
Authors: Rocchi Lorenzo , Fulchignoni Camillo , Donsante Simone , Fanfani Francesco
Published: April 2019

About 10% of patients with lateral epicondylitis are nonresponsive to conservative treatment; as controversy persists on etiology and pathogenesis of this pathology, there is no surgical technique universally approved. The purpose of this study is to describe and evaluate the clinical outcomes of our technique consisting in a semicircumferential and partial detachment of the entire extensor apparatus enthesis. The technique was performed on 14 consecutive patients affected by painful chronic epicondylitis between January 2010 and April 2016. Two patients were lost during follow-up. At 6 months, 1 year, and 2 years after surgery patients were revaluated. Outcomes were assessed using Visual Analog Scale, DASH score (Disability of the Arm, Shoulder, and Hand), Jamar test, and time to return to work. The mean surgical time was 16 minutes. The postoperative outcomes were excellent in most patients as mean Visual Analog Scale score improved from 9.25 to 2.6 and mean DASH score improved from 82.9 to 29.6. No recurrence was recorded at 2 years of follow-up. The procedure is rapid to perform, reproducible and provides low complication rates and no relapse in our experience. As a result, we recommend this technique in nonresponding to conservative treatment lateral epicondylitis.
Poly-Drug Intoxication with Diffuse Muscle Weakness and Impaired Coordination: A Case Report
Authors: Talbot Annie , Marsan Stephanie
Published: April 2019

This report describes a complex set of neurological complications following a history of poly-drug intoxication.
Neuropathic insult increases the responsiveness to acetic acid in mice
Authors: Gurdap Cenk O. , Markwalter Patrick S. , Neddenriep Bradley , Bagdas Deniz , Damaj M. Imad
Published: April 2019

Chronic neuropathic pain is a burden to millions of patients every day. Patients with neuropathic pain will also experience acute pain throughout their everyday lives adding to their nociceptive burden. Using nociceptive models in mice this study aimed to investigate the relationship between acute visceral pain and chronic neuropathic pain in spontaneous and affective behaviors. Neuropathic pain was induced by chronic constriction injury (CCI) of the sciatic nerve of C57BL/6J male mice and examined in assays of acetic acid (AA)-induced stretching or conditioned place aversion to assess nociceptive and aversive behaviors. Stretching induced by a low concentration (0.32%) of AA given intraperitoneally was significantly increased in CCI and paclitaxel-treated animals compared to control animals. A higher concentration (1.2%) of AA was able to induce stretching equally in both neuropathic and control mice. In the conditioned place aversion test, an AA concentration of 0.32% did not induce place aversion in either sham or CCI animals. However, the 1.2% concentration of AA-induced higher place aversion scores in CCI mice compared to sham mice. No difference in place conditioning was observed between paclitaxel and vehicle-treated mice. Overall, our results show that peripheral nerve injury and paclitaxel treatment induces hypersensitivity to AA-induced nociception and place aversion.
Preanalytical Stability of Piperacillin, Tazobactam, Meropenem, and Ceftazidime in Plasma and Whole Blood Using Liquid Chromatography–Tandem Mass Spectrometry
Authors: Mortensen Janni S. , Jensen Berit P. , Zhang Mei , Doogue Matthew
Published: April 2019

Background:

Therapeutic drug monitoring (TDM) is increasingly used to optimize the dosing of beta-lactam antibiotics in critically ill patients. However, beta-lactams are inherently unstable and degrade over time. Hence, patient samples need to be appropriately handled and stored before analysis to generate valid results for TDM. The appropriate handling and storage conditions are not established, with few and conflicting studies on the stability of beta-lactam antibiotics in clinical samples. The aim of this study was to assess the preanalytical stability of piperacillin, tazobactam, meropenem, and ceftazidime in human plasma and whole blood using a liquid chromatography–tandem mass spectrometry method for simultaneous quantification.

Methods:

A reverse phase liquid chromatography–tandem mass spectrometry method for the quantification of piperacillin, tazobactam, meropenem, and ceftazidime in plasma after protein precipitation was developed and validated. The preanalytical stability of these beta-lactams was assessed in EDTA- and citrate-anticoagulated plasma at 24, 4, and −20°C. The whole blood stability of the analytes in EDTA-anticoagulated tubes was assessed at 24°C. Stability was determined by nonlinear regression analysis defined by the lower limit of the 95th confidence interval of the time to 15% of degradation.

Results:

Based on the lower limit of the 95th confidence interval of the time to 15% of degradation, piperacillin, tazobactam, meropenem, and ceftazidime were stable in EDTA-anticoagulated plasma for at least 6 hours at 24°C, 3 days at 4°C, and 4 days at −20°C. Stability in EDTA- and citrate-anticoagulated plasma was similar. Stability in whole blood was similar to plasma at 24°C.

Conclusions:

Plasma samples for the TDM of piperacillin, tazobactam, meropenem, and ceftazidime should be processed within 6 hours if kept at room temperature and within 3 days if kept at 4°C. All long-term storage of samples should be at −80°C.
Radiographic Manifestations of Diffuse Pulmonary Alveolar Derecruitment
Authors: Raja Junaid , Menn Kirsten , Jindal Gaurav , Bokhari Syed A. Jamal
Published: April 2019

Pulmonary alveolar derecruitment is a process of alveolar collapse that occurs in critically ill patients. While the entity and its physiological manifestations are described in the anesthesiology and critical care literature, the radiographic manifestations of alveolar derecruitment have not yet been thoroughly described. This phenomenon can have a similar appearance to pulmonary edema; however, patients often have severe intravascular volume depletion. As the treatment for these 2 entities is essentially contradictory, it is important to be familiar with alveolar derecruitment and consider it as a differential diagnosis when clinically appropriate.
Interventional Therapies for Central Airways
Authors: Dunlap Daniel G. , Ravenel James , Sechrist Jacob , Semaan Roy
Published: April 2019

Central airway obstruction (CAO) is a dangerous and increasingly common problem. CAO refers to lesions causing narrowing of the trachea or mainstem bronchi and is generally divided into malignant and nonmalignant categories. These 2 entities may be caused by a variety of thoracic and extrathoracic diseases. Imaging is critical during the initial assessment of CAO and may help thoracic physicians focus the differential diagnosis and plan the safest and most appropriate diagnostic and therapeutic interventions. However, direct visualization via flexible or rigid bronchoscopy is often necessary for diagnostic and treatment purposes. A large number of procedures can be performed through bronchoscopy, with the goal of relieving the obstruction and improving patency of the airway. Deciding which procedure to perform is based both upon the type of lesion and whether the lesion is due to a malignant or nonmalignant process. Possible interventions include mechanical debridement, laser therapy, argon plasma coagulation, electrocautery, brachytherapy, and stent placement. Immediate postoperative and follow-up imaging is crucial to monitor for immediate, subacute, and chronic complications as well as disease progression and recurrence.
Modulation of DNA polymerase IV activity by UmuD and RecA* observed by single-molecule time-lapse microscopy
Authors: Henrikus Sarah S. , McGrath Amy E. , Jergic Slobodan , Ritger Matthew L. , Pham Phuong T. , Wood Elizabeth A. , Goodman Myron F. , Cox Michael M. , van Oijen Antoine M. , Ghodke Harshad , Robinson Andrew
Published: April 2019

DNA polymerase IV (pol IV) is expressed at increased levels inEscherichia colicells suffering high levels of DNA damage. In a recent single-molecule imaging study, we demonstrated that elevating the pol IV concentration is not sufficient to provide access to binding sites on the nucleoid, suggesting that other factors may recruit pol IV to its substrates once the DNA becomes damaged. Here we extend this work, investigating the proteins UmuD and RecA as potential modulators of pol IV activity. UmuD promotes long-lived association of pol IV with the nucleoid, whereas its cleaved form, UmuD’, which accumulates in DNA-damaged cells, inhibits binding. In agreement with proposed roles for pol IV in homologous recombination, up to 40% of pol IV foci colocalise with a probe for RecA* nucleoprotein filaments in ciprofloxacin-treated cells. A hyperactive RecA mutant,recA(E38K), allows pol IV to bind the nucleoid even in the absence of exogenous DNA damage.In vitro,RecA(E38K) forms RecA*-like structures that can recruit pol IV, even on double-stranded DNA, consistent with a physical interaction between RecA and pol IV. Together, the results indicate that UmuD and RecA modulate the binding of pol IV to its DNA substrates, which frequently coincide with RecA* structures.