bluuebunny/crossref_metadata_2025 huggingface dataset:
Intravoxel Incoherent Motion Magnetic Resonance Imaging with Integrated Slice-specific Shimming for old myocardial infarction: A Pilot Study
Authors: Xiang Shi-Feng , Zhang Xue-Qiang , Yang Su-Jun , Gao Yun-Yun , Gao Bu-Lang , Shi Qing-Lei , Li Shuai
Published: December 2019

Currently, little is known regarding the value of quantitative parameters derived from the intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) with integrated slice-specific shimming (iShim) sequence in detecting old myocardial infarction and myocardial fibrosis. This study was to investigate the value of IVIM-MRI with iShim sequence in diagnosing old myocardial infarction and fibrosis. Thirty-five patients with both old myocardial infarction and myocardial fibrosis and 12 healthy volunteers were prospectively enrolled to undergo cardiac diffusion-weighted imaging (DWI) using seven b-values (0, 20, 60, 80, 120, 200 and 600 s/mm2). The iShim sequence was used for IVIM data acquisition, and the diffusion parameters, D, D* and f values for IVIM, and conventional apparent diffusion coefficient (ADC) were evaluated on the anterior, posterior and lateral walls of the ventricular septum using the short axis of the heart. Significant differences were found in the D, D* and f values between healthy subjects and patients with old myocardial infarction and myocardial fibrosis (P = 0.000), with the median value of the D and f significantly smaller in the myocardial infarction and fibrosis than in the normal control but the median value of D* significantly greater in the myocardial infarction and fibrosis than in the normal control. In the receiver operating curve analysis, the areas under the curve were 0.939, 0.988 and 0.959 for the D, D* and f values, respectively. The sensitivities and specificities were 84.6% and 94.4% for D, 88.9% and 84.6% for D* and 100% and 93.1% for the f values, respectively. In conclusion, the IVIM-derived parameters (D, D* and f) obtained using the iShim DWI technique showed high capacity in diagnosing old myocardial infarction and myocardial fibrosis by providing diffusion and perfusion information, which may have great importance in future clinical practice.
Fine-tuning the diradical character of molecular systems via the heteroatom effect
Authors: Wang Wenxiang , Ge Lingbing , Xue Guodong , Miao Fang , Chen Pingan , Chen Hanjiao , Lin Yiwei , Ni Yong , Xiong Jingyuan , Hu Yuanyuan , Wu Jishan , Zheng Yonghao
Published: December 2019

Heteroatoms were introduced as a novel modification strategy for fine-tuning the diradical character of molecular systems.
NAMI-A preferentially reacts with the Sp1 protein: understanding the anti-metastasis effect of the drug
Authors: Yuan Siming , Chen Siming , Wu Han , Jiang Huan , Zheng Shihui , Zhang Qianling , Liu Yangzhong
Published: December 2019

The anti-metastasis drug NAMI-A selectively reacts with Sp1, a protein associated with cancer metastasis.
Ti3+ self-doped TiO2−x nanowires for efficient electrocatalytic N2 reduction to NH3
Authors: Li Bingyue , Zhu Xiaojuan , Wang Jianwei , Xing Ruimin , Liu Qian , Shi Xifeng , Luo Yonglan , Liu Shanhu , Niu Xiaobin , Sun Xuping
Published: December 2019

Ti3+–TiO2−x/TM behaves as an efficient electrocatalyst for ambient N2-to-NH3 fixation with a high faradaic efficiency of 14.62% and a NH3 yield of 3.51 × 10−11 mol s−1 cm−2 at −0.55 V versus a reversible hydrogen electrode in 0.1 M Na2SO4.
Photocatalytic site-selective C–H difluoroalkylation of aromatic aldehydes
Authors: Tang Wei-Ke , Tang Fei , Xu Jun , Zhang Qi , Dai Jian-Jun , Feng Yi-Si , Xu Hua-Jian
Published: December 2019

The direct photocatalyzed site-selective CAr–H difluoroalkylation of aromatic aldehyde derivatives has been accomplished using a newly explored catalytic system.
Control of C3N4and C4N3carbon nitride nanosheets’ electronic and magnetic properties through embedded atoms
Authors: Bafekry Asadollah , Stampfl Catherine , Akgenc Berna , Ghergherehchi Mitra
Published: December 2019

In the present work, the effect of various embedded atom impurities on tuning electronic and magnetic properties of C3N4and C4N3nanosheets have been studied using first-principles calculations.
A review of defect structure and chemistry in ceria and its solid solutions
Authors: Schmitt Rafael , Nenning Andreas , Kraynis Olga , Korobko Roman , Frenkel Anatoly I. , Lubomirsky Igor , Haile Sossina M. , Rupp Jennifer L. M.
Published: December 2019

Doped and oxygen deficient ceria exhibits local bonding patterns that deviate from the average fluorite symmetry found in XRD.
Finger-powered agglutination lab chip with CMOS image sensing for rapid point-of-care diagnosis applications
Authors: Lu Chung Hsiang , Shih Ting-Sheng , Shih Po-Chen , Pendharkar Gaurav Prashant , Liu Cheng-En , Chen Chi-Kuan , Hsu Long , Chang Hwan-You , Yang Chia-Ling , Liu Cheng-Hsien
Published: December 2019

A finger-powered agglutination lab chip combined with a homemade CMOS image mini-system was developed for point-of-care testing applications related to agglutination effects.
The combined effect of light irradiation and chloride on the physicochemical properties of silver nanoparticles
Authors: Yuan Bojie , Sui Minghao , Lu Hongtao , Wang Jingyu , Qin Jie
Published: December 2019

The evolution of various properties of Ag NPs during light irradiation in Cl−-containing water were investigated, and the mechanism was deeply studied.
The acidic hydrolysis ofN-acetylneuraminic 4,5-oxazoline allows a direct functionalization of the C5 position of Neu5Ac2en (DANA)
Authors: Rota Paola , La Rocca Paolo , Cirillo Federica , Piccoli Marco , Allevi Pietro , Anastasia Luigi
Published: December 2019

The Neu5Ac 4,5-oxazoline ring-opening allows the direct generation of a free C5-amino group key to synthesize antiviral drugs.
A copper-clad lithiophilic current collector for dendrite-free lithium metal anodes
Authors: Chen Ke , Pathak Rajesh , Gurung Ashim , Reza Khan M. , Ghimire Nabin , Pokharel Jyotshna , Baniya Abiral , He Wei , Wu James J. , Qiao Qiquan (Quinn) , Zhou Yue
Published: December 2019

A flexible copper-clad lithiophilic current collector was designed for high coulombic efficiency dendrite-free Li metal anodes.
An in situ structural study on the synthesis and decomposition of LiNiO2
Authors: Bianchini Matteo , Fauth François , Hartmann Pascal , Brezesinski Torsten , Janek Jürgen
Published: December 2019

High-resolution in situ synchrotron XRD shades new light on structural evolution during solid-state synthesis and decomposition processes in LiNiO2.
Biocompatible chitosan-based composites with properties suitable for hyperthermia therapy
Authors: Barra Ana , Alves Zélia , Ferreira Nuno M. , Martins Manuel A. , Oliveira Helena , Ferreira Liliana P. , Cruz M. Margarida , Carvalho Maria de Deus , Neumayer Sabine M. , Rodriguez Brian J. , Nunes Cláudia , Ferreira Paula
Published: December 2019

Sustainably made, flexible and biocompatible composites, having environmentally friendly compositions and multifunctional capabilities, are promising materials for several emerging biomedical applications.
Study of photovoltaic performances for asymmetrical and symmetrical chlorinated thiophene-bridge-based conjugated polymers
Authors: Ma Kangqiao , An Cunbin , Zhang Tao , Lv Qianglong , Zhang Shaoqing , Zhou Pengxin , Zhang Jianqi , Hou Jianhui
Published: December 2019

Two conjugated polymers with asymmetrical and symmetrical chlorinated thiophene-bridges were synthesized to study their photovoltaic performances.
XEDAR inhibits the proliferation and induces apoptosis of gastric cancer cells by regulating JNK signaling pathway
Authors: Yang Lihong , Huang Xiaojun , Wang Wei , Jiang Tao , Ding Feifei
Published: December 2019

X-linked ectodermal dysplasia receptor (XEDAR) has been widely studied in epidermal morphogenesis, but few studies have been conducted on tumorigenesis and development, including gastric cancer. In the present research, we aimed to investigate the effect of XEDAR on gastric cancer and further explore the molecular mechanisms involved. The differential expression of XEDAR in 90 tissue specimens (30 gastric cancer tissues, 30 adjacent tissues and 30 normal tissues) was detected by real-time PCR (RT-PCR) and Western blot. Cell proliferation and apoptosis were explored using MTT and Annexin-V/propidium iodide (PI) assays, respectively. The results revealed that the expression of XEDAR was decreased in gastric cancer tissues and in gastric cancer cell lines, and its expression is regulated by p53 in BGC-823 cells. Furthermore, overexpression of XEDAR inhibited cell proliferation and induced apoptosis in BGC-823 cells. XEDAR moreover inhibited proliferation and induced apoptosis in gastric cancer cells by regulating the JNK signaling pathway. Collectively, the results of the present study suggested that XEDAR inhibits cell proliferation and induces apoptosis by participating in p53-mediated signaling pathway and inhibiting the downstream JNK signaling pathway in gastric cancer.
The energetics of protein–lipid interactions as viewed by molecular simulations
Authors: Corey Robin A. , Stansfeld Phillip J. , Sansom Mark S.P.
Published: December 2019

Membranes are formed from a bilayer containing diverse lipid species with which membrane proteins interact. Integral, membrane proteins are embedded in this bilayer, where they interact with lipids from their surroundings, whilst peripheral membrane proteins bind to lipids at the surface of membranes. Lipid interactions can influence the function of membrane proteins, either directly or allosterically. Both experimental (structural) and computational approaches can reveal lipid binding sites on membrane proteins. It is, therefore, important to understand the free energies of these interactions. This affords a more complete view of the engagement of a particular protein with the biological membrane surrounding it. Here, we describe many computational approaches currently in use for this purpose, including recent advances using both free energy and unbiased simulation methods. In particular, we focus on interactions of integral membrane proteins with cholesterol, and with anionic lipids such as phosphatidylinositol 4,5-bis-phosphate and cardiolipin. Peripheral membrane proteins are exemplified via interactions of PH domains with phosphoinositide-containing membranes. We summarise the current state of the field and provide an outlook on likely future directions of investigation.
Ant Router: An efficient routing protocol for social opportunistic networks using ant routing
Authors: Sharma Deepak Kr. , Singh Swati , Gautam Vishakha , Kumaram Shubham , Sharma Mehul , Pant Shrid
Published: December 2019

Social opportunistic networks are a subclass of opportunistic networks which rely upon the predictability and established patterns of human social behaviour to facilitate the sharing of information by performing message routing. While the forwarding step purely depends upon the movement paradigm of nodes in the network, the said movement makes the network unreliable due to frequent disconnections and delay, and spasmodically connected environment. Various protocols have been developed so far for routing in such networks, whose primary aim is to ensure efficient and reliable message delivery. This study proposes a heuristic‐based scheme for routing messages from the source to the destination using the Ant Algorithm. Problems related to frequent disconnections and inefficient routing are overcome in the proposed protocol through features such as pheromones. This protocol is thoroughly examined via simulation and analysis to assess the performance with other routing protocols in social opportunistic networks under various parameters. The performance criterion for the comparisons includes overhead ratio, average residual energy, average latency, number of dead nodes and average buffer time. The examinations have shown that the authors algorithm is superior to protocols such as Prophet, Epidemic and ProWait on the basis of average latency and buffer time.
Control of quality factor in laterally coupled vertical cavities
Authors: Chen Si , Francis Henry , Ho Chih‐Hua , Wang Yun‐Ran , Che Kai‐Jun , Hopkinson Mark , Jin Chao‐Yuan
Published: December 2019

In this work, the authors demonstrate the control of quality factor (Q‐factor) is laterally coupled vertical cavities. A 3 μm‐side‐length square cavity directly connected to a 1.5 μm‐width, 10 μm‐length Fabry–Perot (FP) cavity has been fabricated and measured. Dynamic tuning of the Q‐factor has been successfully observed by bringing the square cavity and FP cavity into resonance. The vertical‐cavity‐based Q‐factor control scheme provides a new choice for the modulation of light and holds potentials for applications associated with optical information processing.
Silicon nitride polarisation beam splitters: a review
Authors: Tosi Mauricio , Fasciszewki Alejandro , Bulus Rossini Laureano A. , Costanzo Caso Pablo A.
Published: December 2019

In this work, the authors review different design setups of polarisation beam splitters (PBSs) developed in Si3N4 platforms. They analyse different approaches based on directional couplers and interferometers. Then the authors present the design and simulation results of a PBS based on two cascaded multi‐mode interferometers that operate in the whole C‐band. Finally, the authors compare the devices in terms of insertion loss, extinction ratio, bandwidth, footprint and fabrication tolerances.
Classification of drones and birds using convolutional neural networks applied to radar micro‐Doppler spectrogram images
Authors: Rahman Samiur , Robertson Duncan A.
Published: December 2019

This study presents a convolutional neural network‐based drone classification method. The primary criterion for a high‐fidelity neural network‐based classification is a real dataset of large size and diversity for training. The first goal of the study was to create a large database of micro‐Doppler spectrogram images of in‐flight drones and birds. Two separate datasets with the same images have been created, one with RGB images and others with greyscale images. The RGB dataset was used for GoogLeNet architecture‐based training. The greyscale dataset was used for training with a series of architecture developed during this study. Each dataset was further divided into two categories, one with four classes (drone, bird, clutter and noise) and the other with two classes (drone and non‐drone). During training, 20% of the dataset has been used as a validation set. After the completion of training, the models were tested with previously unseen and unlabelled sets of data. The validation and testing accuracy for the developed series network have been found to be 99.6 and 94.4%, respectively, for four classes and 99.3 and 98.3%, respectively, for two classes. The GoogLenet based model showed both validation and testing accuracies to be around 99% for all the cases.
Latest developments on the shielding effectiveness measurements of materials and gaskets in reverberation chambers
Authors: Gifuni Angelo , Gradoni Gabriele , Smartt Christopher , Greedy Steve , Villalón Armando M. , Bastianelli Luca , Moglie Franco , Mariani Primiani Valter , Perna Stefano , Thomas David
Published: December 2019

In this study, the authors present the latest developments on the measurements for the shielding effectiveness (SE) of gaskets and materials in reverberation chambers (RCs). A variant method, where the insertion loss of the fixture is achieved from the SE of the fixture with no sample in the aperture is found; it is appropriate for gaskets and for any flat material having a sufficiently high reflectivity at least on one side. A simple and usable condition under which the simplest method for the SE measurements of gaskets and materials in RCs can be used is also given, as well as particular cases where it can be directly applied are shown. This method, whose applicability is enhanced in this study, can be used for gaskets and any flat sample. Such developments simplify measurement setup and associated procedures. Comparisons of results support the methods for the SE measurements of gaskets and material in RCs shown in this study.
Performance analysis of iterative linear regression‐based clustering in wireless sensor networks
Authors: Meenalochani Manickam , Hemavathi Natarajan , Sudha Selvaraj
Published: December 2019

Clustering, an energy efficient approach is preferred in wireless sensor network due to the limited energy consumption of sensor nodes. Clustering saves energy as the communication is restricted to a few nodes, thereby increasing the network lifetime. Recently, an iterative linear regression‐based clustering is proposed to improve the cluster quality in a wireless sensor network. The quality of clusters so obtained is evaluated through Matlab using the cluster validity analysis platform. However, the performance of the clusters so obtained using iterative linear regression in terms of energy efficiency is not dealt. Hence, an attempt is made to investigate the performance of the network through real time experiments. The network performances are studied in terms of intra‐cluster and inter‐cluster energy consumption, first node death, half node death and last node death. To prove the effectiveness of the proposed technique, it is compared with the standard k‐means clustering algorithm. The results reveal that the clusters obtained using iterative linear regression is efficient in enhancing the lifetime of the wireless sensor network.
Extensor Tendon Entrapment on Computed Tomography Imaging of Distal Radius Fractures
Authors: Nigh Evan D. , Emerson Christopher P. , To David , Barnhill Spencer , Rizzo Michael G. , Nguyen Duc M. , Ugarte Ane , Muñera Felipe , Greif Dylan N. , Jose Jean , Dodds Seth D.
Published: December 2019

Objective To examine the association between distal radius fractures and tendon entrapment identified on computed tomography (CT) imaging.

Patients and Methods After Institutional Review Board approval, we retrospectively reviewed distal radius fractures that underwent CT imaging from an electronic database between January 2006 to February 2018 at a single level 1 hospital trauma center. We categorized all distal radial fractures according to the AO-OTA (AO Foundation/Orthopaedic Trauma Association) classification. Distal upper extremity tendons were assessed for entrapment. Fisher's exact test was used for statistical analysis with significance at p < 0.05.

Results A total of 183 distal radius fractures were identified in 179 patients. A total of 16 fractures (13 males and 3 females) were associated with tendon entrapment. Mechanism of injury included falls (n = 7), motor vehicle accidents (n = 6), dog bites (n = 2), and gunshot wound (n = 1). Entrapped tendons were limited to the extensor compartment and included the extensor pollicis longus (EPL; n = 11), extensor pollicis brevis (n = 1), extensor carpi ulnaris (n = 1), extensor carpi radialis longus (n = 1), and extensor digitorum communis (n = 2). The most commonly associated AO-OTA fracture pattern with tendon entrapment was complete articular radial fractures (2R3C; 69%), eight of which were simple articular with metaphyseal multifragmentary fractures (2R3C2). Of the distal radius fractures, 81% were associated with additional ulnar fractures of varying severity and displacement.

Conclusion Approximately 8.7% of distal radius fractures were retrospectively identified to have tendon entrapment compared with a previously reported incidence of 1.3%. Wrist surgeons and radiologists should have higher suspicion for tendon entrapment and carefully review preoperative CT imaging for tendon entrapment in distal radius fractures especially if there is an intra-articular, multifragmentary injury pattern. Wrist surgeons and radiologists should also have increased suspicion for EPL tendon entrapments given its high incidence in association with distal radius fractures.

Level of Evidence This is a Level III, retrospective cross-sectional study.
The Reliability of the Evaluation of Diffusion-Weighted Imaging in Suspected Stroke by Emergency Physicians
Authors: Onder Halil , Guncu Onur , Hasgul Burak , Dayangac Ibrahim , Gungorer Bulent
Published: December 2019

BackgroundStroke is a leading cause of serious disability and death and its accurate and timely diagnosis is critical for better stroke outcomes. However, recent studies indicate that stroke is among the most common dangerous missed diagnoses. Diffusion-weighted imaging (DWI), which was first introduced in the early 1990s among clinical concerns, has become an invaluable tool in the evaluation processes of patients with suspected ischemic stroke.

ObjectiveHerein, it is aimed to investigate the reliability of the interpretation of DWI in the diagnosis of stroke by emergency physicians.

MethodsDWIs of the patients, evaluated in the Emergency Service of Yozgat City Hospital from April 1, 2017 to September 1, 2017, were retrospectively evaluated by four emergency physicians (specialists) separately in a blind and random fashion. The reliability of the evaluations was calculated using Kappa analyses on SPSS Statistics 20.

ResultsDWI of 154 patients was enrolled in this study. Kappa values were determined to be as 0.911 (almost perfect), 0.909 (almost perfect), 0.897 (almost perfect), 0.779 (substantial), respectively.

DiscussionThe results of this study may suggest that the reliability of DWI interpretation by emergency physicians was pretty high, even it can still be improved. Combining the literature data remarking a substantial number of misdiagnosed stroke patients in the emergency department (ED) and study results, it can be hypothesized that the major problem may be related with rather clinical evaluation processes as well as insufficient neurology consultation. Future reports are warranted to understand the basic problems of stroke evaluation processes in the ED. The results of these studies may aid to develop better solutions while constituting effective stroke programs and initiatives.
Fermion condensation and super pivotal categories
Authors: Aasen David , Lake Ethan , Walker Kevin
Published: December 2019

We study fermionic topological phases using the technique of fermion condensation. We give a prescription for performing fermion condensation in bosonic topological phases that contain a fermion. Our approach to fermion condensation can roughly be understood as coupling the parent bosonic topological phase to a phase of physical fermions and condensing pairs of physical and emergent fermions. There are two distinct types of objects in the resulting fermionic fusion categories, which we call “m-type” and “q-type” objects. The endomorphism algebras of q-type objects are complex Clifford algebras, and they have no analogs in bosonic theories. We construct a fermionic generalization of the tube category, which allows us to compute the quasiparticle excitations arising from the condensed theories. We prove a series of results relating data in fermionic theories to data in their parent bosonic theories; for example, if C is a modular tensor category containing a fermion, then the tube category constructed from the condensed theory satisfies Tube(C/ψ)≅C×(C/ψ). We also study how modular transformations, fusion rules, and coherence relations are modified in the fermionic setting, prove a fermionic version of the Verlinde dimension formula, construct a commuting projector lattice Hamiltonian for fermionic theories, and write down a fermionic version of the Turaev-Viro-Barrett-Westbury state sum. A large portion of this work is devoted to three detailed examples of performing fermion condensation to produce fermionic topological phases: we condense fermions in the Ising theory, the SO(3)6 theory, and the 12E6 theory and compute the quasiparticle excitation spectrum in each of the condensed theories.
Spectroscopic investigation of [Al,N,C,O] refractory molecules
Authors: Trabelsi Tarek , Davis Megan C. , Fortenberry Ryan C. , Francisco Joseph S.
Published: December 2019

As of yet, unexamined aluminum bearing molecules may help elucidate aluminum chemistry and associated refractory atom reactions in the interstellar medium. The flexibility of modern quantum chemistry in the construction and analysis of novel molecules makes it perfectly suited to analyze molecules of astrochemical significance. In this paper, high level ab initio electronic structure calculations using the coupled cluster CCSD(T) and explicitly correlated coupled cluster CCSD(T)-F12 methods with large basis sets extrapolated to the complete basis set limit have been performed on the various [Al,N,C,O] isomers. The anharmonic rotational and vibrational spectroscopic parameters for all isomers are produced with these same levels of theory via quartic force fields and vibrational perturbation theory in order to aid in their potential laboratory or even astrophysical identification. The most stable isomer is determined here to be the aluminum isocyanate radical with linear equilibrium geometry AlNCO (X1Σ+). The NCO antisymmetric stretch of AlNCO has an intensity of 1500 km/mol, which should greatly aid in its infrared detection in the region around 2305 cm−1. Additionally, the AlOCN isomer is relatively low lying, possesses a 5.12 D dipole moment, and has a notable kinetic stability, making it a viable candidate for astronomical observation. All isomers are characterized by small frequencies, which indicates that these are floppy molecules. Isomers with a terminal aluminum atom are especially floppy, with bending modes less than 100 cm−1.
Helicity-dependent terahertz photocurrent and phonon dynamics in hybrid metal halide perovskites
Authors: Cheng D. , Liu Z. , Luo L. , Vaswani C. , Park J.-M. , Yao Y. , Song Z. , Huang C. , Mudiyanselage D.-H. , Kim R. H. J. , Yan Y. , Ho K.-M. , Wang J.
Published: December 2019

We report the discovery of helicity-dependent ultrafast photocurrent generation in organic-inorganic perovskite by measuring terahertz (THz) electric field emissions in the time-domain. We find signatures of the circular photogalvanic effect (CPGE) where right circularly polarized light and left circularly polarized light lead to different photocurrent generation. The direction of photocurrent is also resolved by measuring the polarization of the emitted THz pulses. Furthermore, we observe distinct wavelength-dependent, coherent phonon dynamics using THz pump-induced differential reflectivity, indicative of multiple exciton resonances. Both the CPGE and exciton fine structure, together with theoretical simulations, provide compelling and complementary evidence for the existence of Rashba-type bands in perovskite.
Spin effects as a tool to study photoinduced processes in (S/R)-ketoprofen-(S)-N-methylpyrrolidine dyads
Authors: Polyakov Nikolay , Ageeva Aleksandra , Kiryutin Alexey , Timoshnikov Victor , Magin Ilya , Babenko Simon , Kuznetsova Polina , Kruppa Alexander , Purtov Peter , Stepanov Alexandr , Ivanov Mikhail , Fedin Matvey , Kuibida Leonid , Leshina Tatyana
Published: December 2019

(S/R)-Ketoprofen (KP) is considered to be the strongest photosensitizer among nonsteroidal anti-inflammatory drugs. The photosensitizing reactions are caused by a substituted benzophenone chromophore. It produces various toxic effects through the formation of active paramagnetic intermediates and photoproducts able to attack biological substrates. Photoinduced transformations of KP have been extensively studied in order to identify paramagnetic intermediates. Considerable attention is also paid to photoinduced processes in dyads, where KP is linked with chiral partners, since such processes believed to model the binding of chiral drugs with enzymes and receptors. In the present study, the dyads containing (S)/(R)-KP covalently linked with (S)-N-methylpyrrolidine have been synthesized to examine the peculiarities of photoinduced electron transfer (ET) and hydrogen transfer (HT) in chiral systems. To detect short-lived paramagnetic intermediates, in dyad’s excited triplet state, such as biradical zwitter ion (BZI) and neutral biradical (BR), spin chemistry methods [chemically induced dynamic nuclear polarization (CIDNP) and chemically induced dynamic electron polarization (CIDEP) in arbitrary magnetic fields], allowing indirect detection of transient paramagnetic particles by NMR, have been utilized. Both mentioned processes have been found to begin with the excitation of KP into the triplet state followed by the formation of BZI for ET and BR for HT, respectively. Products of stereoselective attachment of the N-methylpyrrolidine residue to the carbonyl carbon atom of KP occurring in both BZI and BR have been detected by NMR spectral analysis. The value of electronic exchange interaction in biradicals has been determined from the position of the characteristic maximum of hyperpolarization in the CIDNP magnetic field dependences.
Voltage-driven translocation: Defining a capture radius
Authors: Qiao Le , Ignacio Maxime , Slater Gary W.
Published: December 2019

Analyte translocation involves three phases: (i) diffusion in the loading solution, (ii) capture by the pore, and (iii) threading. The capture process remains poorly characterized because it cannot easily be visualized or inferred from indirect measurements. The capture performance of a device is often described by a capture radius generally defined as the radial distance R* at which diffusion-dominated dynamics cross over to field-induced drift. However, this definition is rather ambiguous and the related models are usually oversimplified and studied in the steady-state limit. We investigate different approaches to defining and estimating R* for a charged particle diffusing in a liquid and attracted to the nanopore by the electric field. We present a theoretical analysis of the Péclet number as well as Monte Carlo simulations with different simulation protocols. Our analysis shows that the boundary conditions, pore size, and finite experimental times all matter in the interpretation and calculation of R*.
The contribution of nonhuman primate research to the understanding of emotion and cognition and its clinical relevance
Authors: Bernardi Silvia , Salzman C. Daniel
Published: December 2019

Psychiatric disorders are often conceptualized as arising from dysfunctional interactions between neural systems mediating cognitive and emotional processes. Mechanistic insights into these interactions have been lacking in part because most work in emotions has occurred in rodents, often without concurrent manipulations of cognitive variables. Nonhuman primate (NHP) model systems provide a powerful platform for investigating interactions between cognitive operations and emotions due to NHPs’ strong homology with humans in behavioral repertoire and brain anatomy. Recent electrophysiological studies in NHPs have delineated how neural signals in the amygdala, a brain structure linked to emotion, predict impending appetitive and aversive stimuli. In addition, abstract conceptual information has also been shown to be represented in the amygdala and in interconnected brain structures such as the hippocampus and prefrontal cortex. Flexible adjustments of emotional behavior require the ability to apply conceptual knowledge and generalize to different, often novel, situations, a hallmark example of interactions between cognitive and emotional processes. Elucidating the neural mechanisms that explain how the brain processes conceptual information in relation to emotional variables promises to provide important insights into the pathophysiology accounting for symptoms in neuropsychiatric disorders.
Actin protrusions push at apical junctions to maintain E-cadherin adhesion
Authors: Li John Xiao He , Tang Vivian W. , Brieher William M.
Published: December 2019

Significance

All solid tissues rely on cadherin family cell–cell adhesion molecules for their cohesion and organization. Cadherin adhesive function depends on the actin cytoskeleton, but actin’s contribution to cell–cell adhesion is not fully understood. We demonstrate that actin polymerization-dependent protrusive activity operates continuously to push lateral membranes of neighboring cells together to keep cadherins in contact. Actin-dependent protrusive activity functions as a safety mechanism to quickly repair cadherin adhesive junctions whenever they fail and to prevent myosin-dependent contractile forces from tearing the junctions further apart. Since loss of cadherin adhesion is associated with a number of diseases including cancer progression, then misregulation of actin protrusive activity should be considered as a possible contributing factor to epithelial pathophysiology.
Enhanced expression of β cell Ca
V
3.1 channels impairs insulin release and glucose homeostasis
Authors: Yu Jia , Shi Yue , Zhao Kaixuan , Yang Guang , Yu Lina , Li Yuxin , Andersson Eva-Marie , Ämmälä Carina , Yang Shao-Nian , Berggren Per-Olof
Published: December 2019

Significance

We reveal that increased expression of Ca
V
3.1 channels in rat islets selectively impairs first-phase glucose-stimulated insulin secretion. This deterioration is recapitulated in human islets. Its causal role in diabetes development is clearly manifested in an in vivo diabetic model. Mechanistically, this is due to reduction of phosphorylated FoxO1 in the cytoplasm, elevated FoxO1 nuclear retention, and decreased syntaxin 1A, SNAP-25, and synaptotagmin III in a Ca
V
3.1 channel- and calcineurin-dependent manner. Our findings suggest that elevated expression of Ca
V
3.1 channels in pancreatic islets drives FoxO1-mediated down-regulation of exocytotic proteins resulting in the diabetic phenotypes of impaired insulin secretion and aberrant glucose homeostasis. This causal connection pinpoints β cell Ca
V
3.1 channels as a potential druggable target for antidiabetes therapy.
Identification of Ppar
γ
-modulated miRNA hubs that target the fibrotic tumor microenvironment
Authors: Winkler Ivana , Bitter Catrin , Winkler Sebastian , Weichenhan Dieter , Thavamani Abhishek , Hengstler Jan G. , Borkham-Kamphorst Erawan , Kohlbacher Oliver , Plass Christoph , Geffers Robert , Weiskirchen Ralf , Nordheim Alfred
Published: December 2019

Liver fibrosis interferes with normal liver function and facilitates hepatocellular carcinoma (HCC) development, representing a major threat to human health. Here, we present a comprehensive perspective of microRNA (miRNA) function on targeting the fibrotic microenvironment. Starting from a murine HCC model, we identify a miRNA network composed of 8 miRNA hubs and 54 target genes. We show that let-7, miR-30, miR-29c, miR-335, and miR-338 (collectively termed antifibrotic microRNAs [AF-miRNAs]) down-regulate key structural, signaling, and remodeling components of the extracellular matrix. During fibrogenic transition, these miRNAs are transcriptionally regulated by the transcription factor Ppar

γ

and thus we identify a role of Ppar

γ

as regulator of a functionally related class of AF-miRNAs. The miRNA network is active in human HCC, breast, and lung carcinomas, as well as in 2 independent mouse liver fibrosis models. Therefore, we identify a miRNA:mRNA network that contributes to formation of fibrosis in tumorous and nontumorous organs of mice and humans.
Insights into the lower torso in late Miocene hominoidOreopithecus bambolii
Authors: Hammond Ashley S. , Rook Lorenzo , Anaya Alisha D. , Cioppi Elisabetta , Costeur Loïc , Moyà-Solà Salvador , Almécija Sergio
Published: December 2019

Oreopithecus bambolii(8.3–6.7 million years old) is the latest known hominoid from Europe, dating to approximately the divergence time of thePan-hominin lineages. Despite being the most complete nonhominin hominoid in the fossil record, theO. bamboliiskeleton IGF 11778 has been, for decades, at the center of intense debate regarding the species’ locomotor behavior, phylogenetic position, insular paleoenvironment, and utility as a model for early hominin anatomy. Here we investigate features of the IGF 11778 pelvis and lumbar region based on torso preparations and supplemented by otherO. bamboliimaterial. We correct several crucial interpretations relating to the IGF 11778 anterior inferior iliac spine and lumbar vertebrae structure and identifications. We find that features of the early homininArdipithecus ramidustorso that are argued to have permitted both lordosis and pelvic stabilization during upright walking are not present inO. bambolii. However,O. bamboliialso lacks the complete reorganization for torso stiffness seen in extant great apes (i.e., living members of the Hominidae), and is more similar to large hylobatids in certain aspects of torso form. We discuss the major implications of theO. bamboliilower torso anatomy and howO. bamboliiinforms scenarios of hominoid evolution.
Analysis of allosteric communication in a multienzyme complex by ancestral sequence reconstruction
Authors: Schupfner Michael , Straub Kristina , Busch Florian , Merkl Rainer , Sterner Reinhard
Published: December 2019

Significance

Enzyme complexes consist of several protein subunits that often catalyze sequential reactions in the cell. The activities of the individual subunits must be kept in phase, which requires a sophisticated communication mechanism that is mediated by certain residues. We wanted to elucidate the communication mechanisms between the α-subunits and β-subunits of the tryptophan synthase (TS) complex, which catalyzes the last 2 steps of the biosynthesis of the essential amino acid tryptophan. To this end, an approach involving the reconstruction of TSs from extinct species was followed. The results of our experimental and computational analyses identified 4 residues that contribute to the communication between the α-subunits and β-subunits and provide an explanation of how they act.
Evolution of vascular plants through redeployment of ancient developmental regulators
Authors: Lu Kuan-Ju , van ’t Wout Hofland Nicole , Mor Eliana , Mutte Sumanth , Abrahams Paul , Kato Hirotaka , Vandepoele Klaas , Weijers Dolf , De Rybel Bert
Published: December 2019

Vascular plants provide most of the biomass, food, and feed on earth, yet the molecular innovations that led to the evolution of their conductive tissues are unknown. Here, we reveal the evolutionary trajectory for the heterodimeric TMO5/LHW transcription factor complex, which is rate-limiting for vascular cell proliferation in
Arabidopsis thaliana
. Both regulators have origins predating vascular tissue emergence, and even terrestrialization. We further show that TMO5 evolved its modern function, including dimerization with LHW, at the origin of land plants. A second innovation in LHW, coinciding with vascular plant emergence, conditioned obligate heterodimerization and generated the critical function in vascular development in
Arabidopsis
. In summary, our results suggest that the division potential of vascular cells may have been an important factor contributing to the evolution of vascular plants.
Structure, function, and evolution of
Gga
-AvBD11, the archetype of the structural avian-double-β-defensin family
Authors: Guyot Nicolas , Meudal Hervé , Trapp Sascha , Iochmann Sophie , Silvestre Anne , Jousset Guillaume , Labas Valérie , Reverdiau Pascale , Loth Karine , Hervé Virginie , Aucagne Vincent , Delmas Agnès F. , Rehault-Godbert Sophie , Landon Céline
Published: December 2019

Out of the 14 avian β-defensins identified in the
Gallus gallus
genome, only 3 are present in the chicken egg, including the egg-specific avian β-defensin 11 (
Gga
-AvBD11). Given its specific localization and its established antibacterial activity,
Gga
-AvBD11 appears to play a protective role in embryonic development.
Gga
-AvBD11 is an atypical double-sized defensin, predicted to possess 2 motifs related to β-defensins and 6 disulfide bridges. The 3-dimensional NMR structure of the purified
Gga-
AvBD11 is a compact fold composed of 2 packed β-defensin domains. This fold is the archetype of a structural family, dubbed herein as avian-double-β-defensins (Av-DBD). We speculate that
AvBD11
emanated from a monodomain gene ancestor and that similar events might have occurred in arthropods, leading to another structural family of less compact DBDs. We show that
Gga
-AvBD11 displays antimicrobial activities against gram-positive and gram-negative bacterial pathogens, the avian protozoan
Eimeria tenella
, and avian influenza virus.
Gga
-AvBD11 also shows cytotoxic and antiinvasive activities, suggesting that it may not only be involved in innate protection of the chicken embryo, but also in the (re)modeling of embryonic tissues. Finally, the contribution of either of the 2
Gga
-AvBD11 domains to these biological activities was assessed, using chemically synthesized peptides. Our results point to a critical importance of the cationic N-terminal domain in mediating antibacterial, antiparasitic, and antiinvasive activities, with the C-terminal domain potentiating the 2 latter activities. Strikingly, antiviral activity in infected chicken cells, accompanied by marked cytotoxicity, requires the full-length protein.
Alzheimer’s disease: A clinical perspective and future nonhuman primate research opportunities
Authors: Haque Rafi U. , Levey Allan I.
Published: December 2019

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder that is the sixth leading cause of death and the most common cause of dementia worldwide. Over the last few decades, significant advancements have been made in our understanding of AD by investigating the molecular mechanisms underlying amyloid-β and tau pathology. Despite this progress, no disease-modifying treatments exist for AD, an issue that will exacerbated by the rising costs and prevalence of the disorder. Moreover, effective therapies to address the devastating cognitive and behavioral symptoms are also urgently needed. This perspective focuses on the value of nonhuman primate (NHP) models in bridging the molecular, circuit, and behavioral levels of analysis to better understand the complex genetic and environmental/lifestyle factors that contribute to AD pathogenesis. These investigations could provide an opportunity for translating our understanding of the pathogenesis and physiological mechanisms underlying AD and related disorders into new diagnostic approaches and disease-modifying therapies to prevent disease or restore brain function for symptomatic individuals.
Quantitative determination of atomic buckling of silicene by atomic force microscopy
Authors: Pawlak Rémy , Drechsel Carl , D’Astolfo Philipp , Kisiel Marcin , Meyer Ernst , Cerda Jorge Iribas
Published: December 2019

The atomic buckling in 2D “Xenes” (such as silicene) fosters a plethora of exotic electronic properties such as a quantum spin Hall effect and could be engineered by external strain. Quantifying the buckling magnitude with subangstrom precision is, however, challenging, since epitaxially grown 2D layers exhibit complex restructurings coexisting on the surface. Here, we characterize using low-temperature (5 K) atomic force microscopy (AFM) with CO-terminated tips assisted by density functional theory (DFT) the structure and local symmetry of each prototypical silicene phase on Ag(111) as well as extended defects. Using force spectroscopy, we directly quantify the atomic buckling of these phases within 0.1-Å precision, obtaining corrugations in the 0.8- to 1.1-Å range. The derived band structures further confirm the absence of Dirac cones in any of the silicene phases due to the strong Ag-Si hybridization. Our method paves the way for future atomic-scale analysis of the interplay between structural and electronic properties in other emerging 2D Xenes.
Using machine learning to predict extreme events in complex systems
Authors: Qi Di , Majda Andrew J.
Published: December 2019

Extreme events and the related anomalous statistics are ubiquitously observed in many natural systems, and the development of efficient methods to understand and accurately predict such representative features remains a grand challenge. Here, we investigate the skill of deep learning strategies in the prediction of extreme events in complex turbulent dynamical systems. Deep neural networks have been successfully applied to many imaging processing problems involving big data, and have recently shown potential for the study of dynamical systems. We propose to use a densely connected mixed-scale network model to capture the extreme events appearing in a truncated Korteweg–de Vries (tKdV) statistical framework, which creates anomalous skewed distributions consistent with recent laboratory experiments for shallow water waves across an abrupt depth change, where a remarkable statistical phase transition is generated by varying the inverse temperature parameter in the corresponding Gibbs invariant measures. The neural network is trained using data without knowing the explicit model dynamics, and the training data are only drawn from the near-Gaussian regime of the tKdV model solutions without the occurrence of large extreme values. A relative entropy loss function, together with empirical partition functions, is proposed for measuring the accuracy of the network output where the dominant structures in the turbulent field are emphasized. The optimized network is shown to gain uniformly high skill in accurately predicting the solutions in a wide variety of statistical regimes, including highly skewed extreme events. The technique is promising to be further applied to other complicated high-dimensional systems.
Sweetening the hallmarks of cancer: Galectins as multifunctional mediators of tumor progression
Authors: Girotti María Romina , Salatino Mariana , Dalotto-Moreno Tomás , Rabinovich Gabriel A.
Published: December 2019

Hanahan and Weinberg have proposed 10 organizing principles that enable growth and metastatic dissemination of cancer cells. These distinctive and complementary capabilities, defined as the “hallmarks of cancer,” include the ability of tumor cells and their microenvironment to sustain proliferative signaling, evade growth suppressors, resist cell death, promote replicative immortality, induce angiogenesis, support invasion and metastasis, reprogram energy metabolism, induce genomic instability and inflammation, and trigger evasion of immune responses. These common features are hierarchically regulated through different mechanisms, including those involving glycosylation-dependent programs that influence the biological and clinical impact of each hallmark. Galectins, an evolutionarily conserved family of glycan-binding proteins, have broad influence in tumor progression by rewiring intracellular and extracellular circuits either in cancer or stromal cells, including immune cells, endothelial cells, and fibroblasts. In this review, we dissect the role of galectins in shaping cellular circuitries governing each hallmark of tumors, illustrating relevant examples and highlighting novel opportunities for treating human cancer.
Bulk-boundary quantum oscillations in inhomogeneous Weyl semimetals
Authors: Pikulin Dmitry I , Ilan Roni
Published: December 2019

In a Weyl semimetal, a spatially inhomogeneous Weyl node separation caused by lattice deformations can mimic the action of axial electromagnetic fields. Such fields can locally drive a chiral magnetic effect, a local macroscopic current, in equilibrium. In the present work, we study the interplay of external and intrinsic magnetic fields and explore the fate of bulk boundary oscillations in systems subjected to strain gradients. We show that the emerging intrinsic fields leave distinct hallmarks on the period of the oscillations by modifying the particle trajectories. This makes the oscillations depend on the geometry of the system in an analytically traceable manner. We, therefore, predict that quantum oscillations are a natural way to observe and quantify intrinsic magnetic fields, both of which have not been achieved yet in the solid state.