bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Evaluation of Novel Functional Polymers Derived from Renewable Jasmine Lactone for Stimuli‐Responsive Drug Delivery
Authors: Bansal Kuldeep Kumar , Özliseli Ezgi , Rosling Ari , Rosenholm Jessica Marianne
Published: June 2021

Instances of synthetic polymers obtained from renewable feedstock with the possibility of post‐synthesis functionalization are scarce. Herein, the first ever synthesis and drug delivery application of amphiphilic block copolymer (mPEG‐b‐PJL) derived from renewable jasmine lactone with free allyl groups on the backbone is presented. The polymer is synthesized via facile ring‐opening polymerization and subsequently, UV mediated thiol‐ene click chemistry is utilized for post‐functionalization. The introduction of hydroxyl, carboxyl, and amine functionality to mPEG‐b‐PJL polymer is successfully established. As a proof‐of‐concept demonstration, doxorubicin (DOX) is conjugated on hydroxyl‐terminated polymer (mPEG‐b‐PJL‐OH) via redox responsive disulfide linkage to obtain PJL‐DOX. PJL‐DOX is readily self‐assembled into micelles with an average hydrodynamic size of ≈150 nm and demonstrates reduction‐responsive DOX release. Micelles are evaluated in vitro for cytocompatibility and selective drug release in cancer cells (MDA‐MB‐231) using 10 mm glutathione as a reducing agent. Cytotoxicity and microscopy results confirm a redox‐triggered release of DOX, which is further confirmed by flow cytometry. The introduction of these novel functional polymers can pave the way forward in designing polymer‐drug conjugate‐based smart nano‐carriers.
Curvature Induced by Deflection in Thick Meta‐Plates
Authors: Mirzaali Mohammad J. , Ghorbani Aref , Nakatani Kenichi , Nouri‐Goushki Mahdiyeh , Tümer Nazli , Callens Sebastien J. P. , Janbaz Shahram , Accardo Angelo , Bico José , Habibi Mehdi , Zadpoor Amir A.
Published: June 2021

The design of advanced functional devices often requires the use of intrinsically curved geometries that belong to the realm of non‐Euclidean geometry and remain a challenge for traditional engineering approaches. Here, it is shown how the simple deflection of thick meta‐plates based on hexagonal cellular mesostructures can be used to achieve a wide range of intrinsic (i.e., Gaussian) curvatures, including dome‐like and saddle‐like shapes. Depending on the unit cell structure, non‐auxetic (i.e., positive Poisson ratio) or auxetic (i.e., negative Poisson ratio) plates can be obtained, leading to a negative or positive value of the Gaussian curvature upon bending, respectively. It is found that bending such meta‐plates along their longitudinal direction induces a curvature along their transverse direction. Experimentally and numerically, it is shown how the amplitude of this induced curvature is related to the longitudinal bending and the geometry of the meta‐plate. The approach proposed here constitutes a general route for the rational design of advanced functional devices with intrinsically curved geometries. To demonstrate the merits of this approach, a scaling relationship is presented, and its validity is demonstrated by applying it to 3D‐printed microscale meta‐plates. Several applications for adaptive optical devices with adjustable focal length and soft wearable robotics are presented.
Exploiting Light Interferences to Generate Micrometer‐High Superstructures from Monomeric Azo Materials with Extensive Orientational Mobility
Authors: Rodriguez Florent , Jelken Joachim , Delpouve Nicolas , Laurent Adèle , Garnier Bertrand , Duvail Jean‐Luc , Lagugné‐Labarthet François , Ishow Eléna
Published: June 2021

Photochromic azo materials have stirred considerable interest for their ability to mechanically respond to polarized light through large photoinduced migration and orientation processes. In order to apprehend the microscopic dynamics behind the extensive mass transport occurring under interferential illumination, two azo compounds differing by their propensity to form hydrogen bonds are synthesized and processed as nondoped glassy thin films. Interferential irradiation using polarization and intensity patterns reveals fully distinct responses. Regular nanometer‐high surface relief gratings transform into micrometer superstructures with an amplitude ten times higher than the initial film thickness when using the latter polarization. Systematic comparisons between the azo materials in terms of thermal properties, photochromism in solution and in the solid state, and photomigration are carried out. The progressive formation of superstructures is ascribed to two successive processes. The first one relates to fast photoinduced migration due to the impinging structured light, and the second one is promoted by slower thermally activated “zig‐zag”‐like diffusion and Z‐E thermal relaxation, which in turn requests high orientational mobility of the azo compounds and causes large nanomechanical changes. Such studies should provide novel structural guidelines in terms of material fluidity to rapidly achieve highly structured and rewritable materials at low light irradiance.
Coffee‐Stain‐Free Perovskite Film for Efficient Printed Light‐Emitting Diode
Authors: Li Ya , Chen Zhewei , Liang Dong , Zang Jiaqing , Song Zheheng , Cai Lei , Zou Yatao , Wang Xuechun , Wang Yusheng , Li Pandeng , Gao Xingyu , Ma Zhongsheng , Mu Xinju , El‐Shaer Abdelhamid , Xie Liming , Su Wenming , Song Tao , Sun Baoquan
Published: June 2021

Inkjet printing is a powerful technology for realizing high‐density pixelated perovskite light‐emitting diodes (PeLEDs). However, the coffee‐stain effect in the inkjet printing process often leads to uneven thickness and poor crystallization of printed perovskite features, which deteriorates the performance of PeLEDs. Here, a strategy is developed to suppress the coffee‐stain effect via enhancing Marangoni flow strength. An interfacial poly(vinylpyrrolidone) (PVP) layer is incorporated to tune the surface tension of the underlying hole transport layer (HTL) and enhance the perovskite crystallization. The substrate temperature is also carefully controlled to tune the printing solvent evaporation rate rationally. By optimizing the thickness of the PVP layer and the temperature of the printing stage, the coffee‐stain effect is dramatically restrained. In addition, the interfacial insulating PVP layers play a positive role in suppressing leakage current level of PeLEDs by avoiding any direct electrical contact between HTL and electron transporting layer. Finally, an inkjet‐printed PeLED with a brightness of 3640 cd m–2 and external quantum efficiency of 9.0% is achieved. This work highlights the availability of inkjet‐printing technology for fabricating patterned PeLEDs in information display applications.
Perovskite Quantum Dots for Super‐Resolution Optical Microscopy: Where Strong Photoluminescence Blinking Matters
Authors: Feld Leon G. , Shynkarenko Yevhen , Krieg Franziska , Rainò Gabriele , Kovalenko Maksym V.
Published: June 2021

Blinking nanoscale emitters, typically single molecules, are employed in single‐molecule localization microscopy (SMLM), such as direct stochastic optical reconstruction microscopy (dSTORM), to overcome Abbe's diffraction limit, offering spatial resolution of few tens of nanometers. Colloidal quantum dots (QDs) feature high photostability, ultrahigh absorption cross‐sections and brightness, as well as wide tunability of the emission properties, making them a compelling alternative to organic molecules. Here, CsPbBr3 nanocrystals, the latest addition to the QD family, are explored as probes in SMLM. Because of the strongly suppressed QD photoluminescence blinking (ON/OFF occurrence higher than 90%), it is difficult to resolve emitters with overlapping point‐spread functions by standard dSTORM methods due to false localizations. A new workflow based on ellipticity filtering efficiently identifies false localizations and allows the precise localization of QDs with subwavelength spatial resolution. Aided by Monte‐Carlo simulations, the optimal QD blinking dynamics for dSTORM applications is identified, harnessing the benefits of higher QD absorption cross‐section and the enhanced QD photostability to further expand the field of QD super‐resolution microscopy toward sub‐nanometer spatial resolution.
High‐temperature resistant polyimide‐based sandwich‐structured dielectric nanocomposite films with enhanced energy density and efficiency
Authors: Cai Lixin , Wu Jima , Qin Hongmei , Li Ziwei , Wang Shan , Hu Guo‐Hua , Xiong Chuanxi
Published: June 2021

Development of advanced dielectric materials with both high‐electric energy density and high‐temperature resistant attributes is highly desirable in modern electronics and electrical systems. Herein, a series of polyimide (PI)‐based sandwich‐structured dielectric nanocomposite films have been attempted to develop the advanced high‐temperature resistant capacitor films, wherein the boron nitride nanosheets/PI nanocomposite acts as the outer layers and the zinc oxide (ZnO)/PI as the middle layer. Benefitting from the merits of both fillers and the unique structure, the resulting nanocomposite films can simultaneously achieve both high‐dielectric constant and high‐breakdown strength, as well as low‐electrical conduction loss, thus leading to improved discharged energy densities (Ue) and charge/discharge efficiency (η) at elevated temperatures. It is found that the sandwich‐structured nanocomposite film with 0.4 vol% ZnO (0.4ZnO/PI‐S) can deliver a maximum Ue of 5.29 J cm−3 at 400 MV m−1 and 150°C, which is about 1.9 times that of the pristine PI film. Moreover, outstanding dielectric stability over 10,000 charge/discharge cycles has been demonstrated in such PI‐based sandwich‐structured nanocomposite films at 150°C and 200 MV m−1. This research may provide a new paradigm to explore polymer nanocomposites having excellent energy storage and efficiency at elevated temperatures.
A desmoking algorithm for endoscopic images based on improved U‐Net model
Authors: Lin Jinzhao , Jiang Meiqiu , Pang Yu , Wang Huiqian , Chen Zhu , Yan Chongyuan , Liu Qinghui , Wang Yuanfa
Published: June 2021

In laparoscopic surgery, the smoke generated by operations including electrocautery and laser ablation seriously degrades the quality of endoscopic images. It not only reduces the visibility of the surgery, leading to increased risk of surgery, but also affects the performance of image processing in computer‐assisted surgery such as segmentation, 3D reconstruction and tracking. Therefore, a desmoking algorithm is required to eliminate smoke in endoscopic images. In this article, we study a U‐Net model that can eliminate smoke of the laparoscopic image in real‐time and preserve the natural appearance of the organ surface. Our method is based on the improved U‐Net in which convolutional block attention module is used as an embedded guide mask of the decoder part. The laparoscopic image dataset is provided by the Hamlyn Center, and the Blender software is used to simulate various situations of smoke added to the laparoscopic image for training and testing. For the proposed method, the peak signal‐to‐noise ratio value is up to 29.27 and the structural similarity index is up to 0.945 over the test images. The experimental results demonstrate that the proposed method achieves a better performance than other six existing methods, which is applicable for real‐time endoscopic image processing.
SM‐Detector: A security model based on BERT to detect SMiShing messages in mobile environments
Authors: Ghourabi Abdallah
Published: June 2021

The growing use of SMS by businesses to communicate with their customers has made attackers more interested in smishing attacks. Smishing is a security attack that involves sending a fake SMS message in order to steal the personal credentials of mobile users. This kind of attack has become a serious cyber‐security issue and has caused great financial losses for both people and businesses. In this article we propose a hybrid security model called “SM‐Detector” aiming to detect smishing messages in mobile environments. To increase the efficiency of “SM‐Detector,” we have combined three different detection methods: (i) identification of malicious URLs, (ii) identification of suspected words, phone numbers and emails with regular expression analysis, and (iii) classification of messages using BERT‐based algorithms to distinguish spam messages. “SM‐Detector” also includes a mobile application allowing the user to check their SMS and report smishing messages. Its strength is that it can deal with mixed text messages written in Arabic or English. The experimental evaluation conducted on English and Arabic datasets showed a remarkable accuracy of 99.63%.
Smartphone alcohol breath testing devices underestimate BAC
Authors: Knopf Alison
Published: June 2021

If people, including teens, rely on their phone to tell them if they're safe to drive based on their blood alcohol content (BAC), they may be wrong, a recent study has found. The accuracy of smartphone‐paired devices varies widely, and while some are suitable for both clinical and research purposes, others underestimate the BAC, which creates the potential to mislead intoxicated users.
HHS‐proposed rule gutting HIPAA would especially hurt patients with SUD
Authors: Knopf Alison
Published: June 2021

In the ongoing call to make 42 CFR like the Health Insurance Portability and Accountability Act (HIPAA), people who want access to patient records for alcohol and drug use disorders may be thinking “Be careful what you ask for.” Now the federal Department of Health and Human Services (HHS) has made good on a promise to try to get rid of most of the protections of HIPAA. The proposed modifications to the HIPAA Privacy Rule, published Jan. 21 in the Federal Register and released earlier, would have negative consequences for people with substance use disorder (SUD) — and to all patients — according to comments filed by the Legal Action Center and the American Medical Association.
Comparison of the influence of Martian and Earth's atmospheric environments on terahertz band electromagnetic waves
Authors: Diao Zhuo , Jing Qingfeng , Zhong Weizhi
Published: June 2021

Terahertz waves have wide application prospects in space communication because of their strong penetration ability, wide band, and strong directional antenna. Therefore, it is necessary to study the propagation characteristics of terahertz waves in space, such as in the environment on Mars. In space near Mars, the terahertz link is mainly affected by the absorption attenuation of its atmosphere and the scatter attenuation of heavy dust storms. In this paper, the absorption of 0.1–1 THz waves in the Martian atmosphere is analyzed. The absorption coefficient is calculated based on the theory of atmospheric radiative transfer and the HITRAN database. The influence of temperature, pressure, and altitude on the absorption coefficient is analyzed, and the calculation results are compared with those of Earth's atmosphere. The size distribution of Martian dust particles is then fitted by lognormal distribution, and the transmission characteristics of terahertz waves with different wavelengths are studied based on Mie theory. The research results show the transparent window positions of the attenuation peaks of water vapor and oxygen, which are the main factors of atmospheric transmission attenuation in the 0.1–1 THz band. The attenuation of Martian dust is affected by the size parameter, and it decreases with the visibility of the dust storm. The results provide a reference for terahertz communications in a Martian atmospheric environment and clarify the range of Martian atmospheric fading and dust fading.
The different impacts of the daytime and nighttime land surface temperatures on the alpine grassland phenology
Authors: Li Xiaoting , Guo Wei , Li Shuheng , Zhang Junzhe , Ni Xiangnan
Published: June 2021

Land surface temperature (LST) is often a direct control on herbaceous plants but has been underappreciated on the alpine grassland phenology in response to climate change. In the present study, we used satellite data of the Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) and LST products to study the land surface phenology (LSP) of alpine grasslands in response to LST changes in the Qinghai Lake Basin (QLB), which is on the northeastern Tibetan Plateau. Our results showed that LSP, including the start (SOS), end (EOS), and length (GSL) of the growing season, presented high spatial heterogeneity and had significant correlation with landform elevations. Both averaged SOS and EOS across QLB were advanced from 2001 to 2017, but the greater advancement of SOS compared to that of EOS led to an overall prolonged GSL. Daytime LST (LSTd) and nighttime LST (LSTn) had the contrasting effects on SOS (i.e., SOS can be delayed with the increase in LSTd, while it can be advanced with the increase in LSTn). However, increase in LSTd and LSTn in August had the same advancing effect on EOS. Moreover, LSTd played the dominant role in controlling the grassland phenology. Specifically, an 1°C increase in the LSTd in the nongrowing season (i.e., from previous October to April) significantly postponed the SOS by 2.2 d and advanced the EOS by 1.1 d in August. This study highlights the utility and biological relevance of LST in research of grassland phenology and differential impacts of daytime and nighttime LST on grassland phenology.
Self‐Healing All‐in‐One Energy Storage for Flexible Self‐Powering Ammonia Smartsensors
Authors: Ma Hongting , Lv Fengjuan , Shen Liuxue , Yang Kaizhou , Jiang Yu , Ma Junlin , Geng Xiaodong , Sun Tongrui , Pan Yuzhen , Xie Zhuang , Xue Mianqi , Zhu Nan
Published: June 2021

Self‐healable and flexible all‐in‐one self‐powering smartsensing devices have recently attracted great attention. Herein, a flexible all‐in‐one solid‐state electronic system of polyvinyl alcohol (PVA) hydrogel‐based supercapacitors for self‐powering ammonia smartsensors has been fabricated. Self‐healing supercapacitors are prepared by integrating polypyrrole (PPy) and boron cross‐linked PVA/KCl hydrogel as a sandwich configuration, exhibiting large specific capacitance of 244.81 mF cm−2 at 0.47 mA cm−2, and good charging/discharging stability of 2000 cycles, while ammonia sensors are realized by a SnO2/PPy‐modified conductive PVA hydrogel film, demonstrating an excellent sensing behavior toward NH3 vapor under 50 ppb–500 ppm. As a result, self‐healing supercapacitors could well store energy and then self‐power sensing unit for remotely real‐time detection via a smartphone, acquiring high flexibility of energy‐sensing system. With attractive biocompatibility and self‐healing performance toward various environment, this all‐in‐one flexible energy‐smartsensor system would pave the way to novel fabrication process in realization of wearable self‐healing smart devices.
Food safety and sanitation challenges of public university students in a developing country
Authors: Serrem Kevin , Illés Csaba Bálint , Serrem Charlotte , Atubukha Bridget , Dunay Anna
Published: June 2021

Inadequate catering facilities in Kenyan public universities compel students to handle and prepare their own food, in environments not designated for food preparation such as rooms in hostels. This study investigated the level of food safety and sanitation knowledge, attitude, and practice, among students in an effort to prevent food‐borne diseases. A cross‐sectional study was conducted among 535 students from two public universities in Kenya. Data were obtained through a piloted, structured questionnaire in line with Food and Agriculture Organization (FAO) guidelines, administered to students from seven different departments. Eighty percent of the students had adequate levels of food safety and hygiene knowledge, while 70% had a positive attitude toward food safety and sanitation. An average of 74% engaged in inadequate food safety and hygiene practices, with majority citing lack of equipment as a major contributor. ANOVA results revealed significant correlation between the gender and knowledge and practice of food safety and sanitation (F = 30.328, ρ = 0.000) and (F = 18.177,ρ = 0.000), respectively. Binary logistic regression showed that knowledge (β = 3.677, p < .000) fostered the practice of food safety and sanitation more in comparison with attitude (β = 2.244, p < .000). Kenyan universities should consider introducing food safety courses that emphasize Food Safety Management System (FSMS) and Hazard Analysis Critical Control Point (HACCP) practices and procedures especially to non‐science‐based courses, in addition to providing students with proper cooking and food handling facilities.
Making Climate Change Local: Municipalities and Communities Key to Decarbonization
Authors: Vangala Shreyas , Tomaszkiewicz Ellery , Brady Joe
Published: June 2021

In 2018, the Intergovernmental Panel on Climate Change (IPCC), the United Nations body tasked with assessing climate change and providing information for member nations, published a report including a call to action for world leaders to act quickly to prevent warming beyond 1.5°C. Governments across the world and at all levels are taking notice, and many are mobilizing to meet this challenge. As of May 2021, 1,935 jurisdictions and local governments spanning 826 million citizens have declared a state of climate emergency, including 138 local jurisdictions in the US.
Caregiver–infant and toddler interactions during diapering: Caregiver responsiveness and child well‐being and involvement
Authors: Laurin Deborah E. , Guss Shannon S. , Horm Diane
Published: June 2021

The findings of this empirical research provide new information about the importance of caregiver interactions during care routines, specifically diaper changing, in supporting infant and toddler involvement and well‐being. This correlational study involved observations of 144 separate diapering cycles by 31 caregivers with 74 infants and toddlers in 30 infant and toddler classrooms in a U.S. Midwest city. Based on these observations, caregiver responsiveness was found to be significantly related to both child involvement and child well‐being. Another feature of caregivers’ behavior, caregiver encouragement, was significantly associated with child well‐being, but not child involvement. The study results suggest that caregivers’ behaviors, specifically responsiveness and encouragement, during diapering are vital proximal processes in the moment‐to‐moment interactions between a caregiver and child. Thus, responsiveness and encouragement in care routines should be emphasized in infant care settings and be a focus for caregiver professional development, including pre‐ and in‐service training. Although training related to diapering is often restricted to health concerns, the findings suggest that specific caregiver–child interactions during this care routine may support or hinder children's well‐being and involvement in the moment. Caregiver responsiveness to children's cues in this context may enhance children's opportunities to practice involvement in bidirectional relationships and support children's well‐being.
Establishment of time‐resolved fluoroimmunoassay of IgG4 based on magnetic microspheres
Authors: Wu Qingqing , Hang Chen , Li Ting , Wang Binrong , Qin Yuan , Wang Yigang , Zhou Xiumei , Xia Pengguo , Sheng Huiming , Huang Pei , Huang Biao
Published: June 2021

Background

The abnormal increase in serum IgG4 level is an important clinical symptom of IgG4‐related disease (IgG4‐RD), and the detection of serum IgG4 level is a powerful tool for the diagnosis of IgG4‐RD. This study was conducted to establish a simple and rapid immunoassay for the determination of human serum IgG4 levels.

Methods

Based on the competition method, a novel immunoassay was established for the determination of human serum IgG4 using a combination of time‐resolved fluoroimmunoassay (TRFIA) and magnetic microspheres. IgG4 was coupled with magnetic microspheres and competed with IgG4 in the samples to bind the Eu3+‐labeled anti‐IgG4 antibody. The immunocomplex was separated and washed in a magnetic field, and the fluorescence counts were measured according to the number of dissociated europium ions.

Results

The analytical sensitivity of IgG4‐TRFIA based on magnetic microspheres was 0.006 g/L, and the detection range was 0.006–20 g/L under optimal conditions. The precision, recovery, and specificity of this immunoassay were demonstrated to be acceptable. The clinical application of IgG4‐TRFIA based on magnetic microspheres was evaluated and compared with that of immunonephelometry. The results showed that the two detection methods had a good correlation, with a correlation coefficient of .9871.

Conclusion

IgG4‐TRFIA based on magnetic microspheres has the advantages of high sensitivity, wide detection range, and short analysis time and has the potential to become a useful tool for the diagnosis of IgG4‐RD.
Gatekeeper training for friends and family of individuals at risk of suicide: A systematic review
Authors: Morton Michael , Wang Shijing , Tse Kristen , Chung Carolyn , Bergmans Yvonne , Ceniti Amanda , Flam Shelley , Johannes Robb , Schade Kathryn , Terah Flora , Rizvi Sakina
Published: June 2021

Aims

Gatekeeper training (GKT) is an important suicide prevention strategy. Studies have evaluated the effectiveness of GKT in different populations, often neglecting family and friends who play a vital role in caring for people with suicide risk. This review evaluated GKT programs targeting family and friends to determine their effectiveness in this specific population.

Methods

Academic databases were searched for studies on GKT programs. Programs involving family and friends caring for people with suicide risk were assessed for any impact on knowledge, self‐efficacy, attitudes, and suicide prevention skills.

Results

Seventeen studies were reviewed. GKT showed significant gains on outcomes of interest. Three studies targeted family and friends, with one involving them in program creation and conduction and another adjusting the program after their input.

Conclusions

GKT programs have potentially positive effects on family and friends caring for people with suicide risk. Few programs address the specific needs of this group, and programs adapted specifically for them are scarce. Future program development recommendations are discussed.
Fine structures and their impacts on the characteristic Raman spectra of molten binary alkali tungstates
Authors: Wang Jian , Wang Min , You Jinglin , Lu Liming , Wan Songming , Wu Yongquan , Zheng Shaobo
Published: June 2021

Comparing with the crystalline tungstate compounds, little work has been carried out and reported on the relation among the microstructure, W–O bond lengths, and characteristic Raman‐active vibration wavenumber of the molten tungstates, which allows us to diagnose and determine the structure of unknown clusters existing in and further predict the physicochemical properties of molten binary alkali tungstates. Raman spectra of an ensemble of eight model clusters were simulated in the present work by density functional theory (DFT) to establish the effect of the fine structures and W–Onb (non‐bridging oxygen) bond lengths of W–O complexes on the characteristic wavenumber of W–Onb Raman‐active vibration modes of the molten tungstates. Results show that the characteristic wavenumbers of the symmetric stretching vibration modes of W–Onb bonds increase almost linearly with the decreasing bond length. The characteristic wavenumbers of W–Onb symmetric stretching vibration modes generally follow [WO4]2− > [WO5]4− > [WO6]6− present in the melt simultaneously. The characteristic wavenumbers were also found to increase with the number of bridging oxygen for the same W–O complex. In situ Raman spectra of molten A2WnO3n + 1 (A = Li, Na, K; n = 1, 2, 3) were then measured in order to verify the correlation observed among the microstructure, W–O bond lengths, and characteristic Raman‐active vibration mode wavenumbers. The correlation was successfully applied to deconvolute the in situ Raman spectrum of the molten Na2W3O10.
Numerical Simulations of Gas Sorption Experiments in Polymers: Influence of Aspect Ratio and Pressure Increase Rate on the Determination of Diffusion Coefficient
Authors: Kargar Mahboubeh , Handge Ulrich A.
Published: June 2021

Diffusion and sorption phenomena of gases in polymers are of relevance for a number of technological applications, e.g., polymer foaming and membrane technology. The diffusion coefficient and the solubility, which depend on temperature and applied gas pressure, can be determined using the buoyancy method. In this work, the influence of two important parameters are investigated, i.e., the dimensions of the polymer sample and the pressure increase rate, on the accuracy of the determination of the diffusion coefficient D using gas sorption measurements. Numerical simulations on effectively two‐dimensional diffusion phenomena in polymers are performed in order to obtain “ideal” experimental data. This set of “ideal” experimental data for polymer samples with specified geometrical dimensions is used for determination of the diffusion coefficient based on the analytical solution of Fickian diffusion in one spatial dimension. Different fitting procedures for determination of the diffusion coefficient are compared. Because of the finite time, which is necessary for pressure increase in a sorption experiment, the influence of pressure increase rate is also studied. This analysis reveals that an aspect ratio larger than 32 and a time for pressure increase smaller than approximately 3 × 10−9 m2D−1 is necessary for a reliable determination of diffusion coefficient D.
Theoretical–Experimental Study of the Release of Chlorine during the Synthesis of BHET in the Presence of PVC
Authors: Victoria‐Valenzuela David , Morales‐Cepeda Ana Beatriz , Rivera‐Armenta José Luis , Angel‐Hernandez Miguel Ángel Del
Published: June 2021

This work studies the chlorine (Cl) release during the esterification of terephthalic acid (TPA) and ethylene glycol (EG) due to the addition of different amounts of polyvinyl chloride (PVC) that emulates its presence as an impurity. With the aim to explore the possible effects of PVC presence and its dehydrochlorination during the syntheses of bis(2‐hydroxyethyl) terephthalate (BHET) and with the aid of a mathematical model, the evolution releasing of Cl during PVC dehydrochlorination is analyzed. Theoretical results present a good correlation with experimental data that indicate the presence of Cl in the composition of the final product because the dehydrochlorination is incomplete. Additionally, the model predicts the temperature in that Cl can be completely released avoiding its presence in BHET. These kinds of studies are of particular interest when products with a high degree of purity are required, and Cl is detrimental to end applications.
Improving distortion correction for isotropic high‐resolution 3D diffusion MRI by optimizing Jacobian modulation
Authors: Liu Simin , Xiong Yuhui , Dai Erpeng , Zhang Jieying , Guo Hua
Published: June 2021

Purpose

To improve distortion correction for isotropic high‐resolution whole‐brain 3D diffusion MRI when in a time‐saving acquisition scenario.

Theory and methods

Data were acquired using simultaneous multi‐slab (SMSlab) acquisitions, with a b = 0 image pair encoded by reversed polarity gradients (RPG) for phase encoding (PE) and diffusion weighted images encoded by a single PE direction. Eddy current‐induced distortions were corrected first. During the following susceptibility distortion correction, image deformation was first corrected by the field map estimated from the b = 0 image pair. Intensity variation was subsequently corrected by Jacobian modulation. Two Jacobian modulation methods were compared. They calculated the Jacobian modulation map from the field map, or from the deformation corrected b = 0 image pair, termed as JField and JRPG, respectively. A modified version of the JRPG method, with proper smoothing, was further proposed for improved correction performance, termed as JRPG‐smooth.

Results

Compared to JField modulation, less remaining distortions are observed when using the JRPG and JRPG‐smooth methods, especially in areas with large B0 field inhomogeneity. The original JRPG method causes signal‐to‐noise ratio (SNR) deficiency problem, which manifests as degraded SNR of the diffusion weighted images, while the JRPG‐smooth method maintains the original image SNR. Less estimation errors of diffusion metrics are observed when using the JRPG‐smooth method.

Conclusion

This study improves the distortion correction for isotropic high‐resolution whole‐brain 3D diffusion MRI by optimizing Jacobian modulation. The optimized method outperforms the conventional JField method regarding intensity variation correction and accuracy of diffusion metrics estimation, and outperforms the original JRPG method regarding SNR performance.
AZD8055 enhances in vivo efficacy of afatinib in chordomas
Authors: Zhao Tianna , Siu I‐Mei , Williamson Tara , Zhang Haoyu , Ji Chenchen , Burger Peter C , Connis Nick , Ruzevick Jacob , Xia Menghang , Cottone Lucia , Flanagan Adrienne M , Hann Christine L , Gallia Gary L
Published: June 2021

Chordomas are primary bone tumors that arise in the cranial base, mobile spine, and sacrococcygeal region, affecting patients of all ages. Currently, there are no approved agents for chordoma patients. Here, we evaluated the anti‐tumor efficacy of small molecule inhibitors that target oncogenic pathways in chordoma, as single agents and in combination, to identify novel therapeutic approaches with the greatest translational potential. A panel of small molecule compounds was screened in vivo against patient‐derived xenograft (PDX) models of chordoma, and potentially synergistic combinations were further evaluated using chordoma cell lines and xenograft models. Among the tested agents, inhibitors of EGFR (BIBX 1382, erlotinib, and afatinib), c‐MET (crizotinib), and mTOR (AZD8055) significantly inhibited tumor growth in vivo but did not induce tumor regression. Co‐inhibition of EGFR and c‐MET using erlotinib and crizotinib synergistically reduced cell viability in chordoma cell lines but did not result in enhanced in vivo activity. Co‐inhibition of EGFR and mTOR pathways using afatinib and AZD8055 synergistically reduced cell viability in chordoma cell lines. Importantly, this dual inhibition completely suppressed tumor growth in vivo, showing improved tumor control. Together, these data demonstrate that individual inhibitors of EGFR, c‐MET, and mTOR pathways suppress chordoma growth both in vitro and in vivo. mTOR inhibition increased the efficacy of EGFR inhibition on chordoma growth in several preclinical models. The insights gained from our study potentially provide a novel combination therapeutic strategy for patients with chordoma. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.
Multi‐institutional analysis of treatment modalities in basal ganglia and thalamic germinoma
Authors: Graham Richard T. , Abu‐Arja Mohammad H. , Stanek Joseph R. , Cappellano Andrea , Coleman Christina , Chi Susan , Cooney Tabitha , Dhall Girish , Ellen Jacob G. , Finlay Jonathan L. , Fisher Michael J. , Friedman Gregory K. , Gajjar Amar , Gauvain Karen , Hoffman Lindsey M. , Hukin Juliette , Lucas John T. , Mueller Sabine , Navalkele Pournima , Ronsley Rebecca , Tinkle Christopher , Villeneuve Stephanie , Yeo Kee Kiat , Su Jack M. , Margol Ashley , Gottardo Nicholas G. , Allen Jeffrey , Packer Roger , Bartels Ute , Abdelbaki Mohamed S.
Published: June 2021

Background

Central nervous system (CNS) germinomas are treatment‐sensitive tumors with excellent survival outcomes. Current treatment strategies combine chemotherapy with radiotherapy (RT) in order to reduce the field and dose of RT. Germinomas originating in the basal ganglia/thalamus (BGTGs) have proven challenging to treat given their rarity and poorly defined imaging characteristics. Craniospinal (CSI), whole brain (WBI), whole ventricle (WVI), and focal RT have all been utilized; however, the best treatment strategy remains unclear.

Methods

Retrospective multi‐institutional analysis has been conducted across 18 institutions in four countries.

Results

For 43 cases of nonmetastatic BGTGs, the 5‐ and 10‐year event‐free survivals (EFS) were 85.8% and 81.0%, respectively, while the 5‐ and 10‐year overall survivals (OS) were 100% and 95.5%, respectively (one patient fatality from unrelated cause). Median RT doses were as follows: CSI: 2250 cGy/cGy(RBE) (1980–2400); WBI: 2340 cGy/cGy(RBE) (1800–3000); WVI: 2340 cGy/cGy(RBE) (1800–2550); focal: 3600 cGy (3060–5400). Thirty‐eight patients (90.5%) received chemotherapy. There was no statistically significant difference in the EFS based on initial field extent (p = .84). Nevertheless, no relapses were reported in patients who received CSI or WBI. Chemotherapy alone had significantly inferior EFS compared to combined therapy (p = .0092), but patients were salvageable with RT.

Conclusion

Patients with BGTGs have excellent outcomes and RT proved to be an integral component of the treatment plan. This group of patients should be included in future prospective clinical trials and the best RT field should be investigated further.
Trinuclear salphen–chromium(III)chloride complexes as catalysts for the alternating copolymerization of epoxides and cyclic anhydrides
Authors: Cui Lei , Ren Bai‐Hao , Lu Xiao‐Bing
Published: June 2021

Although the alternating copolymerization of epoxides and cyclic anhydrides is a promising route to aliphatic polyesters, improved catalysts are required to realize commercialization of this process. Herein, trinuclear chromium complexes of salicylaldimine, in conjunction with a nucleophilic cocatalyst, are demonstrated as excellent catalysts for epoxide/cyclic anhydride copolymerization, selectively affording perfectly alternating polyesters. The effect of the distance between the chromium species is investigated by varying the bridging skeleton in a series of trinuclear salphen–Cr(III)Cl complexes for obtaining different Cr–Cr distances. Trinuclear salphenCr(III)–complexes with Cr–Cr distances of approximately 7.3 Å are found to be efficient copolymerization catalysts, even at high temperatures and extremely low catalyst loadings. In particular, a high activity of 10,620 h−1 is obtained for the copolymerization of cyclohexene oxide (CHO) and phthalic anhydride (PA) under a low catalyst loading (<0.01 mol%) at 100 °C. In situ infrared spectroscopy studies suggest that the activation energy of the trinuclear Cr(III)–salphen catalyst for CHO/PA copolymerization is 15 kJ mol−1 lower than that of the corresponding mononuclear catalyst owing to an intramolecular synergistic effect among the metal atoms.
Surface Charge Regulated Asymmetric Ion Transport in Nanoconfined Space
Authors: Wu Yadong , Qian Yongchao , Niu Bo , Chen Jianjun , He Xiaofeng , Yang Linsen , Kong Xiang‐Yu , Zhao Yifei , Lin Xiangbin , Zhou Teng , Jiang Lei , Wen Liping
Published: June 2021

The asymmetric ion transport in the nanoconfined space, similar to that of natural ion channels, has attracted broad interest in sensor, energy conversion, and other related fields. Among these systems, the surface charge plays an important role in regulating ion transport behaviors. Herein, this surface charge‐regulated asymmetric ion transport behavior is systematically explored in the nanoconfined space and the influence on the performance of nanofluidic energy conversion system. The ion transport behaviors in the nanoconfined space are classified into pure diffusion, electrical double layer, and the polarization controlled state. The asymmetric solution environment or surface charge distribution induces asymmetric ion transport behavior which is largely controlled by the low concentration side. The ion‐selectivity and the energy conversion performance can be effectively enhanced by improving the local apparent surface charge (more active sites and higher charge strength) or introducing a selective layer with dense surface charge on the low concentration side. These material design concepts for asymmetric ion transport are further supported by both simulation and experiment. The results provide a significant comprehension for ion behaviors in nanoconfined space and the development of high‐performance energy storage and conversion systems.
A model‐driven approach for semantic web service modeling using web service modeling languages
Authors: Mohseni Mohsen , Sohrabi Mohammad Karim , Dorrigiv Morteza
Published: June 2021

The service‐oriented software engineering approach has been increasingly utilized to design and develop complex distributed systems. Exploiting semantic web technologies to increase utilization of the web services at the semantic level leads to create semantic web services (SWSs). This paper proposes a model‐driven architecture (MDA) to model the SWS and to transform it from a high‐level modeling language, such as the Unified Modeling Language (UML), to a low‐level semantic description, such as the Web Service Modeling Language (WSML). To annotate all aspects of the SWS, a UML profile is provided by extending the UML metamodel. Some stereotypes and tagged values are also defined to support WSML. Therefore, the structure aspects of the SWS are modeled with a class diagram based on stereotypes that are defined in the UML profile. The logical and behavioral aspects of the SWS are modeled and expressed using activity diagrams, sequence diagrams, and Object Constraint Language (OCL). Experimental results show that the proposed approach not only increases the level of independence, accuracy, expressiveness, understandability, and machine processability but also significantly reduces the complexity and heterogeneity. Moreover, the proposed method is also evaluated in comparison with the previous methods of the literature, and the results will show that the proposed method outperforms the other methods in terms of expressiveness, understandability, scalability, level of independence, and accuracy.
“New” Military History
Authors: Hoffenaar Jan
Published: June 2021

This chapter provides an overview of the development of “New military history,” a general term for the broadening – in subject, approaches and methods – of the traditional, narrow operational military historiography. It first deals with the influence of the social, cultural, gender, and global “turns” in general historiography on military historiography. Next, the benefits and possibilities of these new perspectives in military historiography are analyzed, followed by the risks and potential dangers. Finally, the question of what the core of military history should be is discussed and an attempt is made to describe a “comprehensive approach” to analyze military action taken in the past, with a multifaceted “plan of attack” with several possible “axes of attack.” “New” military historians who use a comprehensive approach are best placed to explain how the course of military action has influenced the general course of history and thereby can make a full-fledged contribution to general historiography. This unique quality also gives them the ability and the right to participate in or even initiate broader academic debates.
Three-loop vertex integrals at symmetric point
Authors: Pikelner Andrey
Published: June 2021

Abstract

This paper provides details of the massless three-loop three-point integrals calculation at the symmetric point. Our work aimed to extend known two-loop results for such integrals to the three-loop level. Obtained results can find their application in regularization-invariant symmetric point momentum-subtraction (RI/SMOM) scheme QCD calculations of renormalization group functions and various composite operator matrix elements. To calculate integrals, we solve differential equations for auxiliary integrals by transforming the system to the ε-form. Calculated integrals are expressed through the basis of functions with uniform transcendental weight. We provide expansion up to the transcendental weight six for the basis functions in terms of harmonic polylogarithms with six-root of unity argument.
Low-x improved TMD approach to the lepto- and hadroproduction of a heavy-quark pair
Authors: Altinoluk Tolga , Marquet Cyrille , Taels Pieter
Published: June 2021

Abstract

We study the lepto- and hadroproduction of a heavy-quark pair in the ITMD factorization framework for dilute-dense collisions. Due to the presence of a nonzero quark mass and/or nonzero photon virtuality, new contributions appear compared to the cases of photo- and hadroproduction of dijets, for which the ITMD framework was originally derived. These extra terms are sensitive to gluons that are not fully linearly polarized. At small x, those gluons emerge only when all saturation effects are carefully taken into account. Therefore, the resulting contributions are absent in linear small-x frameworks, where gluons are fully linearly polarized. We show, however, that even for large gluon transverse momentum, these contributions are not always negligible, due to the behavior of the off-shell hard factors.
Correction to: Better outcomes after mini‑subvastus approach for primary total knee arthroplasty: a Bayesian network meta‑analysis
Authors: Migliorini Filippo , Aretini Paolo , Driessen Arne , El Mansy Yasser , Quack Valentin , Tingart Markus , Eschweiler Jörg
Published: June 2021

A correction to this paper has been published: https://doi.org/10.1007/s00590-021-03026-9
On the stability of planetary orbits in binary star systems I. The S-type orbits
Authors: De Cesare G. , Capuzzo-Dolcetta R.
Published: June 2021

Many exoplanets are discovered in binary star systems in internal or in circumbinary orbits. Whether the planet can be habitable or not depends on the possibility to maintain liquid water on its surface, and therefore on the luminosity of its host stars and on the dynamical properties of the planetary orbit. The trajectory of a planet in a double star system can be determined, approximating stars and planet with point masses, by solving numerically the equations of motion of the classical three-body system. In this study, we analyze a large data set of planetary orbits, made up with high precision long integration at varying: the mass of the planet, its distance from the primary star, the mass ratio for the two stars in the binary system, and the eccentricity of the star motion. To simulate the gravitational dynamics, we use a 15th order integration scheme (IAS15, available within the REBOUND framework), that provides an optimal solution for long-term integration. In our data analysis, we evaluate if an orbit is stable or not and also provide the statistics of different types of instability: collisions with the primary or secondary star and planets ejected away from the binary star system. Concerning the stability, we find a significant number of orbits that are only marginally stable, according to the classification introduced by Musielak et al. (Astron. Astrophys. 434:355, 2005). For planets of negligible mass, we estimate the critical semi-major axis $a_{c}$

a
c

as a function of the mass ratio and the eccentricity of the binary, in agreement with the results of Holman and Wiegert (Astron. J. 117:621, 1999). However we find that for very massive planets (Super-Jupiters) the critical semi-major axis decrease in some cases by a few percent, compared to cases in which the mass of the planet is negligible.