bluuebunny/crossref_metadata_2025 huggingface dataset:
Body motion detection and correction in cardiac PET: Phantom and human studies
Authors: Sun Tao , Petibon Yoann , Han Paul K. , Ma Chao , Kim Sally J. W. , Alpert Nathaniel M. , El Fakhri Georges , Ouyang Jinsong
Published: September 2019

Purpose

Patient body motion during a cardiac positron emission tomography (PET) scan can severely degrade image quality. We propose and evaluate a novel method to detect, estimate, and correct body motion in cardiac PET.

Methods

Our method consists of three key components: motion detection, motion estimation, and motion‐compensated image reconstruction. For motion detection, we first divide PET list‐mode data into 1‐s bins and compute the center of mass (COM) of the coincidences’ distribution in each bin. We then compute the covariance matrix within a 25‐s sliding window over the COM signals inside the window. The sum of the eigenvalues of the covariance matrix is used to separate the list‐mode data into “static” (i.e., body motion free) and “moving” (i.e. contaminated by body motion) frames. Each moving frame is further divided into a number of evenly spaced sub‐frames (referred to as “sub‐moving” frames), in which motion is assumed to be negligible. For motion estimation, we first reconstruct the data in each static and sub‐moving frame using a rapid back‐projection technique. We then select the longest static frame as the reference frame and estimate elastic motion transformations to the reference frame from all other static and sub‐moving frames using nonrigid registration. For motion‐compensated image reconstruction, we reconstruct all the list‐mode data into a single image volume in the reference frame by incorporating the estimated motion transformations in the PET system matrix. We evaluated the performance of our approach in both phantom and human studies.

Results

Visually, the motion‐corrected (MC) PET images obtained using the proposed method have better quality and fewer motion artifacts than the images reconstructed without motion correction (NMC). Quantitative analysis indicates that MC yields higher myocardium to blood pool concentration ratios. MC also yields sharper myocardium than NMC.

Conclusions

The proposed body motion correction method improves image quality of cardiac PET.
Comparison of surface guidance and target matching for image‐guided accelerated partial breast irradiation (APBI)
Authors: Zhao Hui , Williams Ned , Poppe Matthew , Sarkar Vikren , Wang Brian , Rassiah‐Szegedi Prema , Huang Y. Jessica , Kokeny Kristine , Gaffney David , Salter Bill
Published: September 2019

Purpose

We investigate the feasibility of surface guided radiation therapy (SGRT) for accelerated partial breast irradiation (APBI) by comparing it with in‐room, fan beam kV computed tomography on rails (CTOR) imaging of the targeted region. The uniqueness of our study is that all patients have multiple daily CTOR scans to compare corresponding SGRT AlignRT (VisionRT, United Kingdom) images to.

Methods/materials

Twelve patients receiving APBI were enrolled in this study. Before each treatment fraction, after patients were setup on tattoos, SGRT was performed using AlignRT, and then target matching was performance using CTOR. The average and maximum difference in shifts between SGRT and CTOR were calculated and analyzed for each patient, so as the correlation between surgical cavity size and shift difference.

Results

Our study showed that SGRT agreed well with CTOR for patients with small surgical cavity volume changes (<10%). There were nine patients who had a ≥5 mm maximum shift difference between SGRT and CTOR along any direction, and in two patients the difference was more than 10 mm (one patient with surgical cavity change 44.3% and one patient with 27 cc cavity volume decrease). All patients, except one, had a mean shift difference < 5 mm along any direction.

Conclusion

For the patients studied here, SGRT appears to be a reasonable and potentially valuable image guidance approach for APBI for patients who experience small changes in surgical cavity volume (<10%) between CT simulation and treatment. However, there is potential for larger alignment errors (up to 11 mm) when using SGRT for patients who experience larger surgical cavity changes.
Immunosuppressive and immunomodulatory therapies for neuromuscular diseases. Part I: Traditional agents
Authors: Farmakidis Constantine , Dimachkie Mazen M. , Pasnoor Mamatha , Barohn Richard J.
Published: September 2019

Immunosuppressive and immunomodulatory therapies have had a major effect on the treatment of immune‐mediated neuromuscular diseases. After the landmark introduction of synthetic corticosteroids, other therapies have become available, including plasma exchange (PLEX), immunoglobulin G (IgG), and steroid‐sparing immunosuppressive drugs. More recently, novel biologically derived and antigen‐specific pharmaceuticals have entered neuromuscular practice. Various levels of evidence guide the use of these treatments. This article reviews current immune‐based therapies in neuromuscular diseases and is divided into two parts. Part I provides an update on the evidence and use of traditional therapies, such as corticosteroids, PLEX, intravenously delivered IgG (IVIG), and steroid‐sparing immunosuppressive drugs. Part II focuses on the recently US Food and Drug Administration–approved therapies eculizumab and subcutaneous IgG (SCIG), the current indications for rituximab in neuromuscular disease, and on novel immunosuppressive therapeutic approaches under development.
On accuracy improvement of microscopic stress/stress sensitivity analysis with the mesh superposition method for heterogeneous materials considering geometrical variation of inclusions
Authors: Sakata S. , Chan Y. , Arai Y.
Published: September 2019

In this paper, a new method is proposed for improving accuracy of microscopic stress analysis/stress sensitivity analysis of heterogeneous materials considering a geometrical variation of inclusions using the mesh superposition method‐based approach. In particular, the analysis, which considers a location variation of inclusions in heterogeneous materials with location change of a local mesh, is a target problem. This problem must be accurately solved for, eg, reliability evaluation with the multiscale stochastic stress analysis considering a microscopic geometrical variation of composites. The influence of a geometrical random variation of inclusions on the stress field is not negligible; further, a finite element mesh must be substantially updated for the evaluation of stress field for a significant realization. Therefore, the mesh superposition method based approach is adopted. In this paper, a problem point in the stress/stress sensitivity analysis considering the geometrical variation of inclusions when using the mesh superposition method is discussed, and improved approaches based on an improved formulation and a relocalization analysis are proposed. The proposed approaches are applied to a stress/stress sensitivity analysis of a heterogeneous material associated with a microstructure of composites. With the numerical results, effectiveness of the proposed approach is discussed.
Marketing challenges and organic farming in India—Does farm size matter?
Authors: Azam Md Sikandar , Shaheen Musarrat , Narbariya Sonali
Published: September 2019

The growing health consciousness among the consumer and increasing awareness about organic food has led numerous opportunities for organic producers. Along with opportunities, there also arise challenges; thus, the main purpose of this study is to explore the marketing challenges faced by the organic and conventional farmers in India. The study also aims to examine the differential association of the marketing challenges on various farm sizes. The sample comprised 400 Indian farmers including both conventional and organic producers. A sequential form of mixed‐method design, that is, qualitative–quantitative, was applied. In the first phase, an exploratory study was convened to find out the marketing challenges among organic and conventional farmers. In the second (quantitative) phase, binomial and multinomial logistics regression was applied to ascertain the differential impact of the marketing challenges on the type of farming and different farm sizes. The results of the qualitative analysis revealed six major marketing challenges faced by the farmers, namely, lack of warehousing facility, lack of price information, inadequate demand for crop, costly transportation, market price variations, and lack of government support. The results suggest there are significant differences in the marketing challenges faced by the conventional and organic farmers across farm sizes. This study is among the few to examine the marketing challenges of organic and conventional farmers in a developing country such as India. The findings will help different stakeholders to frame policies and build strategies to promote organic farming, which will lead to sustainable and responsible consumption in India.
Data variability across Canadian administrative health databases: Differences in content, coding, and completeness
Authors: Doyle Carla M. , Lix Lisa M. , Hemmelgarn Brenda R. , Paterson J. Michael , Renoux Christel
Published: September 2019

Purpose

The Canadian Network for Observational Drug Effect Studies (CNODES) is a network of Canadian research centres using administrative data to conduct distributed drug safety and effectiveness studies. In this study, we compare the provincial administrative databases and illustrate the potential impact of database differences on a CNODES study about domperidone and the risk of ventricular tachyarrhythmia and sudden cardiac death (VT/SCD).

Methods

We assessed the impact of varying versions and precision of the International Classification of Diseases coding system in physician claims data, and the content and completeness of hospital discharge abstracts across CNODES sites, as these variations can introduce differences in the study cohorts formed and affect study results.

Results

In our study of 214 962 patients, hospital diagnosis type (such as most responsible, admitting, or secondary diagnosis) was missing in some provinces, resulting in misclassification of the outcome and variation in rates and risk estimates. Incidence rates of VT/SCD ranged from 19.8 (95% confidence interval [CI] 17.7‐22.2) per 10 000 person‐years in British Columbia to 53.4 (95% CI 50.3‐56.5) in Quebec. While most provinces reported an increased risk of VT/SCD, a null effect was observed in Quebec (rate ratio 1.06; 95% CI 0.79‐1.41).

Conclusions

Distributed analyses allow for rapid responses to drug safety signals. However, variation in characteristics of the administrative data across research centres can influence study results. By identifying the sources of database heterogeneity, one can evaluate the potential biases these differences may introduce, highlighting the importance of considering such variation in distributed networks.
Structural and functional analysis of the Hsp70/Hsp40 chaperone system
Authors: Liu Qinglian , Liang Ce , Zhou Lei
Published: September 2019

As one of the most abundant and highly conserved molecular chaperones, the 70‐kDa heat shock proteins (Hsp70s) play a key role in maintaining cellular protein homeostasis (proteostasis), one of the most fundamental tasks for every living organism. In this role, Hsp70s are inextricably linked to many human diseases, most notably cancers and neurodegenerative diseases, and are increasingly recognized as important drug targets for developing novel therapeutics for these diseases. Hsp40s are a class of essential and universal partners for Hsp70s in almost all aspects of proteostasis. Thus, Hsp70s and Hsp40s together constitute one of the most important chaperone systems across all kingdoms of life. In recent years, we have witnessed significant progress in understanding the molecular mechanism of this chaperone system through structural and functional analysis. This review will focus on this recent progress, mainly from a structural perspective.
Prediction of protein oligomer structures using GALAXY in CASP13
Authors: Baek Minkyung , Park Taeyong , Woo Hyeonuk , Seok Chaok
Published: September 2019

Many proteins need to form oligomers to be functional, so oligomer structures provide important clues to biological roles of proteins. Prediction of oligomer structures therefore can be a useful tool in the absence of experimentally resolved structures. In this article, we describe the server and human methods that we used to predict oligomer structures in the CASP13 experiment. Performances of the methods on the 42 CASP13 oligomer targets consisting of 30 homo‐oligomers and 12 hetero‐oligomers are discussed. Our server method, Seok‐assembly, generated models with interface contact similarity measure greater than 0.2 as model 1 for 11 homo‐oligomer targets when proper templates existed in the database. Model refinement methods such as loop modeling and molecular dynamics (MD)‐based overall refinement failed to improve model qualities when target proteins have domains not covered by templates or when chains have very small interfaces. In human predictions, additional experimental data such as low‐resolution electron microscopy (EM) map were utilized. EM data could assist oligomer structure prediction by providing a global shape of the complex structure.
Population Pharmacokinetic Analysis for Imipenem–Relebactam in Healthy Volunteers and Patients With Bacterial Infections
Authors: Bhagunde Pratik , Patel Parul , Lala Mallika , Watson Kenny , Copalu William , Xu Ming , Kulkarni Pooja , Young Katherine , Rizk Matthew L.
Published: September 2019

Relebactam is a small‐molecule β‐lactamase inhibitor developed as a fixed‐dose combination with imipenem/cilastatin. The pharmacokinetics of relebactam and imipenem across 10 clinical studies were analyzed using data from adult healthy volunteers and patients with bacterial infections. Renal function estimated by creatinine clearance significantly affected the clearance of both compounds, whereas weight and health status were of less clinical significance. Simulations were used to calculate probability of joint target attainment (ratio of free drug area under the curve from 0 to 24 hours to minimum inhibitory concentration (MIC) for relebactam and percentage of time the free drug concentration exceeded the MIC for imipenem) for the proposed imipenem/relebactam dose of 500/250 mg, with adjustments for patients with renal impairment, administered as a 30‐minute intravenous infusion four times daily. These dosing regimens provide sufficient antibacterial coverage (MIC ≤ 4 μg/mL) for all renal groups.
Nonvertical Sidewall Angle Influence on the Efficiency of Diamond‐on‐Insulator Grating Couplers
Authors: Yu. Troschiev Sergey , Trofimov Sergei D. , Tarelkin Sergey A. , Golovanov Anton V. , Luparev Nikolay V. , Prikhodko Dmitrii D. , Bormashov Vitaly S.
Published: September 2019

Planar devices for light transmission between diamond integrated optical circuits and optical fibers or microscope objectives (called grating couplers) can be fabricated by capacitively coupled reactive ion etching (RIE) through contact hard masks micropatterned by e‐beam lithography. However, sidewalls of such etched structures cannot be vertical because their steepness is limited by etching conditions. This study is devoted to numerical simulations of wall steepness influence on diamond‐based grating coupler efficiency at 637 and 1550 nm wavelengths. A simple genetic algorithm to find the optimal device geometry is used herein. The maximum grating coupler efficiency remains almost constant at the wall steepness from 90° to 60° and decreases at lower values. In the specified range, changes in the wall steepness can be fully compensated by changing the width of grating coupler ridges (fill factor). Lowering the wall steepness gives rise to other parameters' tolerances. The study proves that fast and robust capacitively coupled RIE of diamond is a suitable method for creating diamond grating couplers.
Simulation of Structure Parameters' Influence on the Threshold Voltage of Normally‐Off p‐GaN/AlGaN/GaN Transistors
Authors: Osvald Jozef
Published: September 2019

The influence of different parameters of p‐GaN/AlGaN/GaN structure on a threshold voltage of transistors is studied. The parameters that are varied are the thickness of the p‐type GaN layer, its doping concentration, doping concentration of the GaN channel layer, and Schottky barrier height. Increasing the thickness of the p‐GaN layer is found to increase the threshold voltage. Also, increasing doping concentration of the p‐GaN layer increases the threshold voltage. The doping concentration of the GaN channel layer has the decisive effect on the possibility to use capacitance measurement for the threshold voltage assessment. Simulations show an interesting result of the Schottky barrier height threshold voltage dependence. For higher Schottky barrier height, lower threshold voltage is received, which is connected with the contribution of the negative differential capacitance of the p‐GaN layer. This starts to increase for higher positive voltage if the Schottky barrier height is lower.
First‐Principles Study of Metal Atoms Adsorption on 2D Dumbbell C4N
Authors: Xu Min , Wang Hongyan , Sun Songsong , Li Hengtao , Li Xiumei , Chen Yuanzheng , Ni Yuxiang
Published: September 2019

Similar to graphene, zero bandgap is found in the recently proposed 2D dumbbell C4N (DB C4N), which limits its applications as electronic devices. Surface adsorption effectively modifies the electronic and magnetic properties of the 2D materials. Herein, the adsorption behaviors of 16 metal atoms adsorbed on the DB C4N, including alkali metals, alkaline earth metals, 3d transition metals (TMs), and precious metals, are investigated using the density functional theory. The electronic and magnetic properties of the adatom–C4N systems are systematically explored by analyzing the adsorption energies, the density of states (DOS), the band structures, the charge transfer, the total magnetic moments, the work function, and the dipole moment. It is revealed that the alkali metals (Li, Na), alkaline‐earth metals (Be, Mg), 3d TMs (Ti, V, Cr, Mn, Fe, Co), and precious metals (Ag, Pt, Au) open the zero bandgap of DB C4N via charge transfer between the adatoms and the DB C4N surface. Moreover, the 3d transition and precious metals adatoms induce magnetism in the monolayer C4N. These results qualify the metal‐adsorbed C4N systems as promising candidates for building outstanding electronic and spintronic devices in the future.
Consequences of regularizing the Sawyer–Eliassen equation in balance models for tropical cyclone behaviour
Authors: Wang Shanghong , Smith Roger K.
Published: September 2019

The consequences of regularizing the Sawyer–Eliassen equation to calculate the stream function for the axisymmetric secondary circulation of a tropical cyclone are explored. Regularization is an ad hoc procedure in which the coefficients of the equation are suitably modified to replace negative values of the discriminant by small positive values, thereby ensuring that the equation is globally elliptic. The consequences of the procedure may be understood in terms of the analogue behaviour of a stretched membrane subject to a particular force distribution. Several regularization procedures are assessed by comparing the azimuthally averaged radial flow from a three‐dimensional numerical simulation of a tropical cyclone with that from an axisymmetric balance calculation of the Sawyer–Eliassen equation, forced by diabatic and frictional terms diagnosed from the simulation. The comparison shows that the largest challenge for regularization occurs in regions of inertial instability, especially when the diagnosed forcing overlaps with such regions. In the example shown, the diagnosed balanced flow is sensitive to the particular regularization procedure and none of the procedures examined give a flow that is structurally and quantitatively close to that obtained from the numerical solution in and near the region of regularization. The flow in regions of large vertical shear that are common in the lower part of the boundary layer is less sensitive to the regularization procedure, even though such regions are ones in which there is (frictional) forcing. Nevertheless, there are comparatively large differences between the low‐level inflow in the azimuthally averaged numerical solution and the axisymmetric balance solution. These differences can be attributed to the intrinsic lack of balance in the boundary layer. This finding, together with the issues associated with regularization, is further confirmation that balance dynamics is unable to adequately capture the flow in the boundary layer, contrary to recent claims.
Electrospray ionization enters the final frontier: Mass spectrometry's role in understanding electrospray thrusters and their plumes
Authors: Patrick Amanda L.
Published: September 2019

Electrospray thrusters using ionic liquid (IL)‐based propellants are quickly gaining popularity in spacecraft design. Mass spectrometry is especially well‐suited to provide important knowledge on the fundamentals of how these systems work and on evaluating their efficiencies and impacts, given that the operating principles of electrospray thrusters closely mimics the mass spectrometry experiment – in both ions are generated by electrospray and then enter a vacuum. Here, electrospray thruster technology and IL‐based propellants are briefly introduced. This introduction is then followed by a discussion of mass spectrometry's current contribution to the study of IL‐based electrospray thrusters – with a focus on electrospray, dissociation, and spectroscopy studies – and a brief discussion of areas ripe for immediate contributions from the mass spectrometry community.
Math matters: mathematical knowledge plays an essential role in Chinese undergraduates' stock‐and‐flow task performance
Authors: Qi Liang , Gonzalez Cleotilde
Published: September 2019

People's understanding of accumulation (stock) and of rates of change (flows) is essential to successful decision making in dynamic environments. However, past research suggests that highly educated Western people are often unable to infer the behavior of stock–flow systems. In an empirical study involving a population of university students in China, we tested whether mathematical knowledge, global–local processing and domain experience affect participants' performance in stock–flow tasks. We find that Chinese undergraduates had good performance in general, and individuals with more mathematical knowledge performed better on stock–flow tasks. We discuss the possible reasons that explain these participants' success. Future research needs to extend our work to more diverse populations across different cultures, nations and education systems. Comparative studies on the content of math education under a cross‐cultural frame are desirable to uncover more essential factors for people's understanding of stock–flow structures.

© 2019 System Dynamics Society
When do investors prefer copycats? Conditions influencing the evaluation of innovative and imitative ventures
Authors: Fu Yingzhu , Tietz Matthias A.
Published: September 2019

Research Summary

This article investigates the conditions under which investors preferentially evaluate fast follower business model copycats (BMCs)—less novel, imitative ventures—over novel ventures. Employing a conjoint experiment, we find that venture investors prefer fast follower BMCs when the venture team has major capability advantages in exploitation (compared to exploration). Further, we find that investors' experience reduces their preference for fast follower BMCs when the team's capability advantage is in exploitation, and reduces their preference for novel ventures when the team is strong in exploration. These findings provide important theoretical and managerial implications.

Managerial Summary

Business model copycats represent a popular phenomenon in the global market. Fast follower BMCs are especially influential as many of them received millions of dollars of investment, and achieved billions of dollars in evaluations, both resulting in worldwide recognition. But although fast follower BMCs have the potential to conquer any market, they are not always highly valued by investors when initiating their businesses. We investigate when this is the case and find that team exploration–exploitation capabilities influence investors' evaluation preference toward novel ventures and fast follower BMCs. If entrepreneurs are skilled in exploitation, creating a fast follower BMC venture might be a great pitch to secure investment. Yet, if entrepreneurs are mostly competitive in exploration, creating fast follower BMCs does not attract investment easily.
Effects of Silver Ions on High‐Speed Electroless Copper
Authors: Wu Minxian , Xu Chao , Wang Wenchang , Wang Shiying , Mitsuzaki Naotoshi , Chen Zhidong
Published: September 2019

Formaldehyde is one of the mostly used reductants in electroless copper. Silver ions were introduced into the plating bath to improve the plating rates and the film ductility. The linear scan voltammetry was used to study the influence of silver ions on the reduction behavior of copper, which indicates that the silver ions were co‐reduced with copper. The incorporation of silver increased copper deposition rate. The plating rate increased from 17 μm h−1 in the silver‐free solution to 29 μm h−1 as 25 mg L−1 Ag2SO4 was added. Folding tests were performed to illustrate the effect of silver on film ductility. The addition of silver ions in the plating baths improved the folding endurance of copper layers. The stability of the plating bath containing 20 mg L−1 Ag2SO4 was investigated using UV/Vis absorption spectroscopy. The bath was stable for at least 2 weeks.
Enhanced Skin Permeation of Hydrocortisone Using Nanoemulsion as Potential Vehicle
Authors: Altamimi Mohammad , Haq Nazrul , Alshehri Sultan , Qamar Wajhul , Shakeel Faiyaz
Published: September 2019

The current work was performed to estimate the solubility and Hansen solubility parameters of a poorly soluble corticosteroid hydrocortisone (HCN) in various components of nanoemulsion and to enhance the skin permeation rate of HCN using nanoemulsions as potential vehicles. Screening studies suggested the use of Capryol‐90 (oil), Triton‐X100 (surfactant) and Transcutol‐HP (cosurfactant) in the preparation of HCN nanoemulsions. HCN nanoemulsions were developed using low energy emulsification technique and characterized for droplet size, plolydispersity index (PDI), zeta potential (ZP), refractive index (RI), percent of transmittance (% T) and transmission electron microscopy (TEM) and evaluated for drug release behavior. Selected nanoemulsions and control (HCN suspension) were subjected to in vitro skin permeation studies. Optimized formula HSN8 showed droplet size of 52.6 nm, PDI of 0.109, ZP of −33.72 mV, RI of 1.337 and % T of 97.68%. TEM confirmed spherical‐shaped droplets in nanometer range. In vitro drug release evaluation suggested significant release of HCN from optimized nanoemulsion (98.52%) compared with control (35.85%). Skin permeation profile of HCN from optimized nanoemulsion was also significant compared with control. These results suggested the potential of nanoemulsion in enhancing the transdermal delivery of HCN via rat skin.
Does it pay to be a multinational? A large‐sample, cross‐national replication assessing the multinationality–performance relationship
Authors: Pisani Niccolò , Garcia‐Bernardo Javier , Heemskerk Eelke
Published: September 2019

Research Summary

Does it pay to be a multinational? Despite decades of empirical research, we still do not know. We undertake a large‐sample, cross‐national replication of Lu and Beamish (2004) and Berry and Kaul's (2016) works to examine whether the multinationality–performance relationship is S‐shaped in a 2009–2016 panel of 889,865 firm‐year observations. Using a two‐stage least squares fixed‐effects model that accounts for endogeneity on a subsample of 32,835 multinationals from 64 countries, we find no evidence of an S‐shaped relationship; nor do we see it in any of the single‐country contexts. Our results show no evidence of any within‐firm effect of multinationality on performance, highlighting the need for more contextually‐grounded research focused on explaining between‐firm effects to advance our theoretical and empirical understanding of the multinationality‐performance relationship.

Managerial Summary

We replicate two studies that examined the relationship between a firm's multinationality and its performance. Lu and Beamish (2004) found evidence of an S‐shaped relationship—with performance first decreasing, then increasing, then decreasing again as firms expanded abroad—in a sample of Japanese firms; Berry and Kaul (2016) found no evidence of an S‐shaped pattern in a sample of U.S. multinationals. We test for the same relationship using data from nearly 250,000 firms based in over 100 countries from 2009 to 2016 and find no evidence of an S‐shaped pattern or of any effect of multinationality. Our study thus adds substantial evidence to the one shown by Berry and Kaul (2016), emphasizing the need to focus on how contextual differences influence the multinationality–performance relationship.
Investor experience and innovation performance: The mediating role of external cooperation
Authors: Boh Wai Fong , Huang Cheng‐Jen , Wu Anne
Published: September 2019

Research Summary

We add to the literature examining the ownership‐innovation relationship by examining two major investor types: corporate investors and family investors. We use organizational environmental scanning as a new perspective to understand how these investors' capabilities influence firms' external cooperation and innovation performance. We found that corporate investors with broad investment experience strengthen a firm's environmental scanning, enhancing innovation performance by increasing the number of external cooperation activities the firm engages in. Conversely, family investors' broad investment experience tend to be negatively associated with the number of external cooperation and with firm innovation. Our results show that investors influence firm innovation not simply through a monitoring role but also by affecting firms' abilities to innovate, once we factor in the types of investors and their capabilities.

Managerial Summary

We investigate how two different types of investors, corporate and family, influence the innovation performance of publicly‐traded high‐tech firms in Taiwan. We found that the presence of major corporate investors with broad investment experience enhances firms' innovation performance by increasing external cooperation activities firms engage in. Corporate investors appear to enhance organizations' environmental scanning abilities and, in turn, their innovation performance. Conversely, family investors' broad investment experience is negatively associated with firm innovation because such firms engage in fewer external cooperation activities. A focus on control and social cohesion in family firms appears to decrease the emphasis on external knowledge acquisition when family investors have broad investment experience. In summary, our results show that investors' breadth of investment experience influences firms' ability to innovate.
Efficient Copper‐Doped Antimony Sulfide Thin‐Film Solar Cells via Coevaporation Method
Authors: Ishaq Muhammad , Deng Hui , Farooq Umar , Zhang Huan , Yang Xiaokun , Shah Usman Ali , Song Haisheng
Published: September 2019

Sb2S3 being a light‐absorbing material is used for photovoltaic (PV) application due to its superior stability and progressive power conversion efficiency (PCE) benefiting from its low cost, less toxic, earth‐abundant, and facile nature. Due to the difficulty in efficient doping for such 1D structure, the performance of as‐fabricated thin‐film solar cells is limited by high resistivity and hole extraction barrier. Herein, a coevaporation scheme is introduced for copper‐doped Sb2S3 by rapid thermal evaporation (RTE). The Cu‐doped Sb2S3 thin film discloses the enhanced crystallinity with a grain diameter greater than 1 µm and conductivity along with improved carrier concentration. At the same time, the deep valance band obtains a minor upshift, favoring the hole extraction at back contact. Consequently, all the PV parameters are enhanced leading to the PCE boosting from 4.18% to 4.61%. Herein, a facile doping technique is demonstrated to improve its performance without any modification of the present RTE method.
An Investigation on the Strengthening Mechanism Based on Grain‐Boundary Misorientation of High‐Strength Pipeline Steel
Authors: Duan Qiang , Pan Hongbo , Fu Bin , Yan Jun
Published: September 2019

The microstructure and grain‐boundary misorientation of X80 high‐strength pipeline steel are analyzed using the scanning electron microscope, the electron backscatter diffraction, and the transmission electron microscope, and the effect of grain‐boundary orientation on slip dislocation is investigated by constructing a grain‐boundary dislocation model. The results show that the anisotropy of the mechanical properties of X80 pipeline steel is related not only to grain size and microstructure type but also to grain‐boundary orientation, which the obstruction effect of the high‐angle grain boundary on slip dislocation is significantly greater than that of the low‐angle grain boundary. The larger the orientation difference is, the more disorderly the arrangement of atoms on both sides of grain boundary is, and the more difficult it is for dislocations to slip across grain boundary, so the strengthening effect is more remarkable. Also, when the grain‐boundary misorientation is greater than 15°, the strengthening effect tends to stabilize due to the influence of the interfacial superposition.
Coupled shear‐flexural model for dynamic analysis of fixed‐base tall buildings with tuned mass dampers
Authors: Huergo Iván F. , Hernández Hugo
Published: September 2019

An equivalent discrete model is developed for time domain dynamic analysis of uniform high‐rise shear wall‐frame buildings with fixed base and carrying any number of tuned mass dampers (TMDs). The equivalent model consists of a flexural cantilever beam and a shear cantilever beam connected in parallel by a finite number of axially rigid members that allow the consideration of intermediate modes of lateral deformation. The proposed model was validated by a building whose lateral resisting system consists of a combination of shear walls and braced frames. The results showed the effectiveness of TMDs to reduce the peak displacements, interstory drift ratio, and accelerations when the building is subjected to a seismic load. The root mean square accelerations due to along‐wind loads also decrease if TMDs are attached to the building.
Effects of cigarette smoke components on myocardial differentiation of mouse embryonic stem cells
Authors: Kim Cho‐Won , Go Ryeo‐Eun , Ko Eul Bee , Jeung Eui‐Bae , Kim Min‐Seok , Choi Kyung‐Chul
Published: September 2019

The heart is the first organ formed in the developing fetus, and abnormal development of the heart is a major cause of fetal death. The adverse effects of cigarette smoke on the heart have been well established, but it is not well understood how cigarette smoke components regulate signaling molecules and cardiac specific functions during the early differentiation stage of the embryonic heart. In this study, we identified changes in the size of mouse embryoid bodies (mEBs) in response to treatment with cigarette smoke extract (CSE) via regulation of HDAC2, p53, p21, and cyclin D1 protein expression, which are cardiac differentiation and cell‐cycle markers, respectively. In addition, exposure of mouse embryonic stem cells (mESCs) to cigarette smoke components inhibited myocardial differentiation and development through the expression of HDAC1, HDAC2, GATA4, NKX2‐5, TBX5, HAND1, and Troponin I. Long‐term exposure studies showed that CSE and nicotine may delay the development of mouse cardiomyocytes from mESCs and inhibit the contractibility, which is a fundamental function of the heart. Taken together, these findings suggest that cigarette smoke components, including nicotine, may affect abnormal myocardial differentiation and development.
Incorporating local ecological knowledge to explore wolverine distribution in Alberta, Canada
Authors: Webb Shevenell M. , Anderson Robert B. , Jokinen Michael E. , Abercrombie Bill , Bildson Brian , Manzer Douglas L.
Published: September 2019

Wolverines (Gulo gulo) occur at low densities in remote areas that are typically difficult to access, which has resulted in a lack of baseline data and uncertain status across parts of their range. We surveyed trappers in 2012 to gather information on local ecological knowledge of wolverine occurrence across a range of latitudes (49–59°N) in Alberta, Canada. We received questionnaires from 164 trapping areas in the Boreal Forest, Foothills, and Rocky Mountains. Similar to results from other methods of data collection, trapper observations of wolverines were associated with cooler climates and less anthropogenic disturbance. When we included data from all regions, the best model that explained recent wolverine observations included percent intact forest within the surrounding area. The odds ratio suggested that each increase of 1% in the amount of intact forest increased the odds of a trapper observing wolverine sign by 4%. In the Boreal Forest, the top model indicated that wolverines were more likely to be found in areas that had a cooler climate and more intact forest. Insights from trappers provided valuable baseline data on a sensitive species that is complementary to other research findings, and stimulated hypotheses that wolverines are linked to cooler climates and less disturbed environments. © 2019 Alberta Conservation Association. Wildlife Society Bulletin Published by Wiley Periodicals, Inc on behalf of The Wildlife Society.
TLR7 activation in epilepsy of tuberous sclerosis complex
Authors: Dombkowski Alan A. , Cukovic Daniela , Bagla Shruti , Jones McKenzie , Caruso Joseph A. , Chugani Harry T. , Chugani Diane C.
Published: September 2019

Background

Neuroinflammation and toll-like receptors (TLR) of the innate immune system have been implicated in epilepsy. We previously reported high levels of microRNAs miR-142-3p and miR-223-3p in epileptogenic brain tissue resected for the treatment of intractable epilepsy in children with tuberous sclerosis complex (TSC). As miR-142-3p has recently been reported to be a ligand and activator of TLR7, a detector of exogenous and endogenous single-stranded RNA, we evaluated TLR7 expression and downstream IL23A activation in surgically resected TSC brain tissue.

Methods

Gene expression analysis was performed on cortical tissue obtained from surgery of TSC children with pharmacoresistent epilepsy. Expression of TLRs 2, 4 and 7 was measured using NanoString nCounter assays. Real-time quantitative PCR was used to confirm TLR7 expression and compare TLR7 activation, indicated by IL-23A levels, to levels of miR-142-3p. Protein markers characteristic for TLR7 activation were assessed using data from our existing quantitative proteomics dataset of TSC tissue. Capillary electrophoresis Western blots were used to confirm TLR7 protein expression in a subset of samples.

Results

TLR7 transcript expression was present in all TSC specimens. The signaling competent form of TLR7 protein was detected in the membrane fraction of each sample tested. Downstream activation of TLR7 was found in epileptogenic lesions having elevated neuroinflammation indicated by clinical neuroimaging. TLR7 activity was significantly associated with tissue levels of miR-142-3p.

Conclusion

TLR7 activation by microRNAs may contribute to the neuroinflammatory cascade in epilepsy in TSC. Further characterization of this mechanism may enable the combined of use of neuroimaging and TLR7 inhibitors in a personalized approach towards the treatment of intractable epilepsy.
On-line Search in Two-Dimensional Environment
Authors: Dereniowski Dariusz , Osula Dorota
Published: September 2019

We consider the following on-line pursuit-evasion problem. A team of mobile agents called searchers starts at an arbitrary node of an unknown network. Their goal is to execute a search strategy that guarantees capturing a fast and invisible intruder regardless of its movements using as few searchers as possible. We require that the strategy is connected and monotone, that is, at each point of the execution the part of the graph that is guaranteed to be free of the fugitive is connected and whenever some node gains a property that it cannot be occupied by the fugitive, the strategy must operate in such a way to keep this property till its end. As a way of modeling two-dimensional shapes, we restrict our attention to networks that are embedded into partial grids: nodes are placed on the plane at integer coordinates and only nodes at distance one can be adjacent. Agents do not have any knowledge about the grapha priori, but they recognize the direction of the incident edge (up, down, left or right). We give an on-line algorithm for the searchers that allows them to compute a connected and monotone strategy that guarantees searching any unknown partial grid with the use of$O(\sqrt {n})$O(n)searchers, wherenis the number of nodes in the grid. As for a lower bound, there exist partial grids that require${\varOmega }(\sqrt {n})$Ω(n)searchers. Moreover, we prove that for each on-line searching algorithm there is a partial grid that forces the algorithm to use${\varOmega }(\sqrt {n})$Ω(n)searchers but$O(\log n)$O(logn)searchers are sufficient in the off-line scenario. This gives a lower bound on${\varOmega }(\sqrt {n}/\log n)$Ω(n/logn)in terms of achievable competitive ratio of any on-line algorithm.
No head regeneration here: regeneration capacity and stem cell dynamics of Theama mediterranea (Polycladida, Platyhelminthes)
Authors: Bertemes Philip , Grosbusch Alexandra L. , Egger Bernhard
Published: September 2019

Research on the regeneration potential of flatworms (Platyhelminthes) has been mainly undertaken with planarians (Tricladida), where most species can regenerate a head and no proliferation takes place in the blastema, i.e. the early undifferentiated regenerative tissue. Only few studies are available for an early-branching group within the Platyhelminthes, the Polycladida. Head regeneration in polyclads is not possible, with a single exception from a study performed more than 100 years ago:Cestoplanawas reported to be able to regenerate a head if cut a short distance behind the brain. Here, we show that ‘Cestoplana’ was misdetermined and most likely was the small interstitial polycladTheama mediterranea. We revisited regeneration capacity and dynamics ofT. mediterraneawith live observations and stainings of musculature, nervous system, and proliferating and differentiating stem cells. In our experiments, after transversal amputation, only animals retaining more than half of the brain could fully restore the head including the brain. If completely removed, the brain was never found to regenerate to any extent. Different from planarians, but comparable to other free-living flatworms we detected cell proliferation within the posterior regeneration blastema inT. mediterranea. Similar to other free-living flatworms, proliferation did not occur within, but only outside, the differentiating organ primordia. Our results strongly imply that brain regeneration in the absence of the latter is not possible in any polyclad studied so far. Also, it appears that proliferation of stem cells within the regeneration blastema is a plesiomorphy in flatworms and that planarians are derived in this character.
CT-based study of vertebral and intravertebral rotation in right thoracic adolescent idiopathic scoliosis
Authors: Brink Rob C. , Homans Jelle F. , Schlösser Tom P. C. , van Stralen Marijn , Vincken Koen L. , Shi Lin , Chu Winnie C. W. , Viergever Max A. , Castelein René M. , Cheng Jack C. Y.
Published: September 2019

Purpose

To define the longitudinal rotation axis around which individual vertebrae rotate, and to establish the various extra- and intravertebral rotation patterns in thoracic adolescent idiopathic scoliosis (AIS) patients, for better understanding of the 3D development of the rotational deformity.

Methods

Seventy high-resolution CT scans from an existing database of thoracic AIS patients (Cobb angle: 46°–109°) were included to determine the vertebral axial rotation, rotation radius, intravertebral axial rotation, and local mechanical torsion for each spinal level, using previously validated image processing techniques.

Results

For all levels, the longitudinal rotation axis, from which the vertebrae rotate away from the midline, was localized posterior to the spine. The axis became closer to the spine at the apex: apex, r = 11.5 ± 5.1 cm versus two levels above (radius = 15.8 ± 8.5 cm; p < 0.001) and beneath (radius = 14.2 ± 8.2 cm; p < 0.001). The vertebral axial rotation, intravertebral axial rotation, and local mechanical torsion of the vertebral bodies were largest at the apex (21.9° ± 7.4°, 8.7° ± 13.5° and 3.0° ± 2.5°) and decreased toward the neutral, junctional zones (p < 0.001).

Conclusion

In AIS, the vertebrae rotate away around an axis that is localized posterior to the spine. The distance between this axis and the spine is minimal at the apex and increases gradually to the neutral zones. The vertebral axial rotation is accompanied by smaller amounts of intravertebral rotation and local mechanical torsion, which increases toward the apical region. The altered morphology and alignment are important for a better understanding of the 3D pathoanatomical development of AIS and better therapeutic planning for bracing and surgical intervention.

Graphic abstract

These slides can be retrieved under Electronic Supplementary Material.
Effectiveness of a brief psychotherapeutic intervention compared with treatment as usual for adolescent nonsuicidal self-injury: a single-centre, randomised controlled trial
Authors: Kaess Michael , Edinger Alexandra , Fischer-Waldschmidt Gloria , Parzer Peter , Brunner Romuald , Resch Franz
Published: September 2019

Although nonsuicidal self-injury (NSSI) is a clinically significant behavior, evidence-based, specific, time-, and cost-effective treatment approaches are lacking. The aim of this study was to compare the efficacies of a brief cognitive-behavioral psychotherapy manual, the Cutting Down Programme (CDP), and treatment as usual (TAU) in the treatment of adolescent NSSI. We conducted a single-centre randomised controlled trial (RCT). Eligible participants were aged 12–17 years engaging in repetitive NSSI (at least 5 times within the past 6 months). We randomly allocated 74 participants to CDP (n = 37) or TAU (n = 37; in a 1:1 ratio). Outcome measures were administered before treatment (T0), directly after CDP or 4 months after baseline evaluation in the TAU group (T1), and another 6 months later (T2; primary endpoint). Primary outcome was a 50% reduction in NSSI frequency within the past 6 months at 10-month follow-up (T2). Regarding the primary outcome, there were no significant differences between the CDP (n = 26; 70.3%) and TAU group [n = 27; 73.0%; χ2(1) = 0.07; p = 0.797]; NSSI frequency within the past 6 months was significantly reduced at T2 [χ2(1) = 12.45; p < 0.001] with no between-group difference [χ2(1) = 0.14; p = 0.704]. However, we found a significant group x point of measurement interaction [χ2(2) = 7.78; p = 0.021] regarding NSSI within the last month indicating at T1. CDP was equally effective and achieved faster recovery compared to a significantly more intensive TAU in treating adolescent NSSI. The CDP could provide a brief and pragmatic first treatment within a stepped-care model for NSSI in routine clinical care.

Clinical Trial Registration The trial was prospectively registered in the German Registry of Clinical Trials (https://www.drks.de; DRKS00003605) and is now complete.