bluuebunny/crossref_metadata_2025 huggingface dataset:
A new high‐order accurate conservative finite difference scheme for the coupled nonlinear Schrödinger equations
Authors: He Yuyu , Wang Xiaofeng , Dai Weizhong , Deng Yaqing
Published: June 2021

In this paper, a fourth‐order accurate conservative finite difference scheme for solving the coupled nonlinear Schrödinger (CNLS) equations is proposed. Conservation of the discrete energy and masses, priori estimates, existence and uniqueness of numerical solutions, convergence with second‐order in time and fourth‐order in space, and stability of the present scheme are proved by the discrete energy method. A convergent iterative method for the present scheme is developed. Numerical experiments are given to support the theoretical analysis.
Ppb level detection of carbonyl sulfide and ethene and study resonant frequencies using laser photoacoustic spectroscopy
Authors: Mohebbifar Mohammad Reza
Published: June 2021

Laser photoacoustic spectroscopy is a laser measurement method with high sensitivity, good selectivity, nondestructive, and fast response (real‐time). In the present work, to detect carbonyl sulfide and ethene gases and measure resonant frequencies and signals, the photoacoustic spectroscopy system was designed and set up. The detection limit of this system to trace ethene and carbonyl sulfide was measured 3 ppb and 8 ppb, respectively. Also, for these two gases at the presence of different buffer gases, the resonant frequency and photoacoustic signal were recorded. The results showed that among the used buffer gases, xenon has the best acoustic performance and gives the highest photoacoustic signal. The signal also increased with increasing pressure of buffer gas, because increasing the pressure leads to improved collisional processes. The study of resonant frequencies of this system for these two gases in the presence of buffer gases showed that with increasing the pressure of xenon, argon, and nitrogen buffer gases from 65 to 765 Torr, the resonant frequency does not change significantly. But in the case of helium buffer gas, these resonant frequency changes are significant, and as the helium pressure increases by 65 to 765 Torr, the resonant frequencies of carbonyl sulfide and ethene change from 2016 to 2630 Hz and from 2100 to 2740 Hz, respectively. The reason for the different behavior of helium is the higher speed of sound in helium than in other buffer gases.
Reflector antenna shaping by regularized B‐spline in conjunction with one‐sided least square optimization
Authors: Mirhadi Salma , Aryanian Iman
Published: June 2021

In this paper, we have proposed to use regularized B‐spline for shaping a reflector antenna surface to realize a contoured beam for satellite applications. In order to meet fabrication constraints, this method allows the user to control the smoothness of the surface using only one parameter. In fact, instead of imposing constraints on the radius of curvature, for the selected points of the reflector surface, the whole smoothness of the surface can be controlled. For this purpose, a regularization term based on the strain energy of B‐spline functions must be added to the objective function of the optimization. Due to the fact that the regularization term is a quadratic function of the optimization variables, it is suggested to use one‐sided least square optimization. The results show the flexibility of the proposed method, in which the surface smoothness and performance goodness of the antenna can be tuned using only one parameter.
A compact circular polarized metamaterial‐inspired fabric antenna for WBAN applications
Authors: Pathan Tarannum , Karn Rajneesh
Published: June 2021

A compact textile antenna with circular polarization (CP) is implemented for Industrial, Scientific, and Medical applications for wireless body area network with radio band 2.4 GHz. A metamaterial‐inspired radiating element is used to achieve a size reduction of up to 85% against the conventional textile antenna. The CP is obtained by trimming the corners of the radiating element. A rectangular slot place with strip line construct a metamaterial‐inspired radiator and U‐slot is imparted below the radiator by using defected ground structure technique to enhance the antenna bandwidth. This antenna has a physical area of 0.25 × 0.22 × 0.016 λg and is implemented on denim jeans substrate of thickness h = 1.6 mm and εr = 1.6. With the presented design, measured bandwidth of 5.8% (2.37–2.51 GHz). The axial ratio bandwidth of 80 MHz (2.40−2.48 GHz), and a peak gain of 2.70 dBi has been acquired. A perfect matching is observed between measured and simulated results. This novel integrated design is suitable for all body area network communication systems where flexibility and compactness are desirable.
Interfractional diaphragmatic position variation according to stomach volume change during respiratory‐gated radiotherapy for hepatocellular carcinoma
Authors: Kim Tae Gyu , Kang Ki Mun , Park Byungdo , Park Jeehoon , Song Yun Gyu , Kim Kwang Min , Shim Sanggoon , Yu Kil Jong , Lee Hyoun Wook
Published: June 2021

Purpose

We evaluated the correlation between stomach volume change and interfractional baseline shifts of the diaphragm in image‐guided radiotherapy (IGRT) for hepatocellular carcinoma (HCC).

Materials and methods

Twenty‐four patients with HCC underwent ten fractions of IGRT, and a total of 240 cone beam computed tomography (CBCT) and on‐board imager (OBI) kV image sets were acquired. These image sets were retrospectively analyzed. Baseline shifts of the diaphragm relative to bone and stomach volume change ratios were evaluated using four‐dimensional simulation CT, kV image, and CBCT images. Associations between baseline shifts and patient physiologic factors were investigated.

Results

The average baseline shift of the diaphragm in the superior‐inferior (SI) direction was 1.5 mm (standard deviation 4.6 mm), which was higher than the shift in other directions (0.7, 2.0 mm and 0.9, 2.6 mm in right‐left (RL) and anterior‐posterior (AP) directions, respectively). Interfractional baseline shifts of the diaphragm in the SI and AP directions were positively correlated with the stomach volume change ratio (Pearson's r: 0.416 and 0.302, p‐value: <0.001 and <0.001, respectively).

Conclusions

The interfractional baseline shifts of the diaphragm in the SI and AP directions correlated well with stomach volume changes. Efforts to maintain a constant stomach volume before the simulation and each treatment, such as fasting, may reduce interfractional baseline shifts of liver tumors.
Assessment of the impact of CT calibration procedures for proton therapy planning on pediatric treatments
Authors: Bär Esther , Collins‐Fekete Charles‐Antoine , Rompokos Vasilis , Zhang Ying , Gaze Mark N. , Warry Alison , Poynter Andrew , Royle Gary
Published: June 2021

Purpose

Relative stopping powers (RSPs) for proton therapy are estimated using single‐energy computed tomography (SECT), calibrated with standardized tissues of the adult male. It is assumed that those tissues are representative of tissues of all age and sex. Female, male, and pediatric tissues differ from one another in density and composition. In this study, we use tabulated pediatric tissues and computational phantoms to investigate the impact of this assumption on pediatric proton therapy. The potential of dual‐energy CT (DECT) to improve the accuracy of these calculations is explored.

Methods

We study 51 human body tissues, categorized into male/female for the age groups newborn, 1‐, 5‐, 10‐, and 15‐year‐old children, and adult, with given compositions and densities. CT numbers are simulated and RSPs are estimated using SECT and DECT methods. Estimated tissue RSPs from each method are compared to theoretical RSPs. The dose and range errors of each approach are evaluated on three computational phantoms (Ewing's sarcoma, salivary sarcoma, and glioma) derived from pediatric proton therapy patients.

Results

With SECT, soft tissues have mean estimation errors and standard deviation up to (1.96 ± 4.18)% observed in newborns, compared to (0.20 ± 1.15)% in adult males. Mean estimation errors for bones are up to (−3.35 ± 4.76)% in pediatrics as opposed to (0.10 ± 0.66)% in adult males. With DECT, mean errors reduce to (0.17 ± 0.13)% and (0.23 ± 0.22)% in newborns (soft tissues/bones). With SECT, dose errors in a Ewing's sarcoma phantom are exceeding 5 Gy (10% of prescribed dose) at the distal end of the treatment field, with volumes of dose errors >5 Gy of  mm3. Similar observations are made in the head and neck phantoms, with overdoses to healthy tissue exceeding 2 Gy (4%). A systematic Bragg peak shift resulting in either over‐ or underdosage of healthy tissues and target volumes depending on the crossed tissues RSP prediction errors is observed. Water equivalent range errors of single beams are between −1.53 and 5.50 mm (min, max) (Ewing's sarcoma phantom), −0.78 and 3.62 mm (salivary sarcoma phantom), and −0.43 and 1.41 mm (glioma phantom). DECT can reduce dose errors to <1 Gy and range errors to <1 mm.

Conclusion

Single‐energy computed tomography estimates RSPs for pediatric tissues with systematic shifts. DECT improves the accuracy of RSPs and dose distributions in pediatric tissues compared to the SECT calibration curve based on adult male tissues.
Fast dynamic brain PET imaging using stochastic variational prediction for recurrent frame generation
Authors: Sanaat Amirhossein , Mirsadeghi Ehsan , Razeghi Behrooz , Ginovart Nathalie , Zaidi Habib
Published: June 2021

Purpose

We assess the performance of a recurrent frame generation algorithm for prediction of late frames from initial frames in dynamic brain PET imaging.

Methods

Clinical dynamic18F‐DOPA brain PET/CT studies of 46 subjects with ten folds cross‐validation were retrospectively employed. A novel stochastic adversarial video prediction model was implemented to predict the last 13 frames (25–90 minutes) from the initial 13 frames (0–25 minutes). The quantitative analysis of the predicted dynamic PET frames was performed for the test and validation dataset using established metrics.

Results

The predicted dynamic images demonstrated that the model is capable of predicting the trend of change in time‐varying tracer biodistribution. The Bland‐Altman plots reported the lowest tracer uptake bias (−0.04) for the putamen region and the smallest variance (95% CI: −0.38, +0.14) for the cerebellum. The region‐wise Patlak graphical analysis in the caudate and putamen regions for eight subjects from the test and validation dataset showed that the average bias forand distribution volume was 4.3%, 5.1% and 4.4%, 4.2%, (P‐value <0.05), respectively.

Conclusion

We have developed a novel deep learning approach for fast dynamic brain PET imaging capable of generating the last 65 minutes time frames from the initial 25 minutes frames, thus enabling significant reduction in scanning time.
Evaluating the effects of transcutaneous tibial nerve stimulation or pelvic floor muscle training on sexual dysfunction in female multiple sclerosis patients reporting overactive bladder
Authors: Polat Dunya Cansu , Tülek Zeliha , Kürtüncü Murat , Gündüz Tuncay , Panicker Jalesh N. , Eraksoy Mefkure
Published: June 2021

Aims

Sexual dysfunction (SD) is common in female patients with multiple sclerosis (MS) reporting overactive bladder (OAB) symptoms. The aim of the study was to evaluate the effects of transcutaneous tibial nerve stimulation (TTNS) and pelvic floor muscle training (PFMT) with biofeedback on SD in female patients with MS reporting OAB symptoms.

Methods

Patients with overactive bladder and SD were allocated to receive TTNS or PFMT daily. Overactive bladder symptoms, sexual functions, and sexual quality of life were assessed at baseline and 6th weeks. Female Sexual Function Index (FSFI), Overactive Bladder Questionnaire (OABv‐8), and Sexual Quality of Life‐Female (SQoL‐F) questionnaires were used.

Results

Thirty patients (TTNS = 10, PFMT = 20) were included in the study. Compared to baseline, total FSFIOABv‐8, and SQoL‐F scores improved in both TTNS (p = 0.005, p = 0.011, p = 0.444, respectively) and PFMT (p = 0.002, p = 0.001, p = 0.001, respectively) groups. Between‐group comparisons did not show any significant differences.

Conclusion

This study demonstrates the efficacy of both TTNS and PFMT for improving sexual function in female MS patients with OAB symptoms, but did not show superiority of any particular method. Further studies are required to investigate the differences between these two non‐invasive methods.
Business analytics in service operations—Lessons from healthcare operations
Authors: Baron Opher
Published: June 2021

We present an expanded framework for the use of business analytics in projects. To the commonly used descriptive, predictive, and prescriptive analytics, we add comparative analytics, wherein we compare the performance of systems under different interventions. This framework provides a conceptual roadmap for the implementation of business analytics projects. We then demonstrate this framework using recent operations research literature on analytics in healthcare, summarizing papers focusing on one of these aspects. Next, we discuss queue mining as an example of theory and practice illustrative of these aspects. We conclude there is room for further work by operations researchers and management scientists within business analytics projects generally and the healthcare industry more specifically. We argue future work should consider both theory and practice, especially within prescriptive analytics projects, where analysis through the lens of operations research and management science is imperative. We provide some thoughts on the current and future state of operations research and management science in business analytics.
Investigating critical factors that encourage public‐private partnership in infrastructure projects in emerging economies: Evidence from the Republic of India
Authors: Sharma Rakesh Kumar , Bhalla Neba , Goyal Abhimanyu
Published: June 2021

Using a distinctive set of data from 2006 to 2018, this study inquires into the various factors of Public‐Private Partnerships (PPPs) in infrastructure projects. Sixteen exogenous variables from extant literature are used to identify significant factors to forecast the future flow of PPPs in the different states of the Republic of India. Two measures of PPP infrastructure projects that is, cost of the project (log value) and the percentage of total project cost are used as endogenous variables. The used data set is associated with a total of 62 PPP projects financed in 10 states of the Republic of India. Three alternative methods namely, OLS, FMOLS, and DOLS are used to check the consistency of the findings. According to three techniques of unit root tests, the data series of different variables are found to be stationary at the first difference. Johansen's cointegration technique reflects that there is cointegration in both the proposed models for the PPPs. Further, the empirical findings of the study reflect that the size (population), capital and revenue budgets & development expenditures have a positive relationship with the dependent variables. On the other side, some of the exogenous variables namely, regional disparities, GDP, FDI, political stability, debt, and fiscal indicator showcase an adverse effect on the flow of the PPP projects. The present study shall be lucrative for the state governments in addition to the private parties involved in the PPP projects. The identified significant variables of the present study will be useful to forecast the upcoming number of PPP projects in the various Indian States.
Local response to the COVID‐19 pandemic: The case of Nepal
Authors: Mainali Raju , Tosun Mehmet S. , Yilmaz Serdar
Published: June 2021

Outbreak of the coronavirus pandemic is testing governments' capacity. Generally, considerable attention is paid to the capacity and response of the central or national governments; however, COVID‐19 pandemic is local in nature. Although central authorities have important roles to play in COVID‐19 response, local governments, being closer to people, are best‐positioned to form the first line of defense.
Single‐cell analysis of mouse and human prostate reveals novel fibroblasts with specialized distribution and microenvironment interactions
Authors: Joseph Diya B , Henry Gervaise H , Malewska Alicia , Reese Jeffrey C , Mauck Ryan J , Gahan Jeffrey C , Hutchinson Ryan C , Malladi Venkat S , Roehrborn Claus G , Vezina Chad M , Strand Douglas W
Published: June 2021

Stromal–epithelial interactions are critical to the morphogenesis, differentiation, and homeostasis of the prostate, but the molecular identity and anatomy of discrete stromal cell types is poorly understood. Using single‐cell RNA sequencing, we identified and validated the in situ localization of three smooth muscle subtypes (prostate smooth muscle, pericytes, and vascular smooth muscle) and two novel fibroblast subtypes in human prostate. Peri‐epithelial fibroblasts (APOD+) wrap around epithelial structures, whereas interstitial fibroblasts (C7+) are interspersed in extracellular matrix. In contrast, the mouse displayed three fibroblast subtypes with distinct proximal–distal and lobe‐specific distribution patterns. Statistical analysis of mouse and human fibroblasts showed transcriptional correlation between mouse prostate (C3+) and urethral (Lgr5+) fibroblasts and the human interstitial fibroblast subtype. Both urethral fibroblasts (Lgr5+) and ductal fibroblasts (Wnt2+) in the mouse contribute to a proximal Wnt/Tgfb signaling niche that is absent in human prostate. Instead, human peri‐epithelial fibroblasts express secreted WNT inhibitors SFRPs and DKK1, which could serve as a buffer against stromal WNT ligands by creating a localized signaling niche around individual prostate glands. We also identified proximal–distal fibroblast density differences in human prostate that could amplify stromal signaling around proximal prostate ducts. In human benign prostatic hyperplasia, fibroblast subtypes upregulate critical immunoregulatory pathways and show distinct distributions in stromal and glandular phenotypes. A detailed taxonomy of leukocytes in benign prostatic hyperplasia reveals an influx of myeloid dendritic cells, T cells and B cells, resembling a mucosal inflammatory disorder. A receptor–ligand interaction analysis of all cell types revealed a central role for fibroblasts in growth factor, morphogen, and chemokine signaling to endothelia, epithelia, and leukocytes. These data are foundational to the development of new therapeutic targets in benign prostatic hyperplasia. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Adrenocortical tumours in children and adolescents: The EXPeRT/PARTNER diagnostic and therapeutic recommendations
Authors: Virgone Calogero , Roganovic Jelena , Vorwerk Peter , Redlich Antje , Schneider Dominik T. , Janic Dragana , Bien Ewa , López‐Almaraz Ricardo , Godzinski Jan , Osterlundh Gustaf , Stachowicz‐Stencel Teresa , Brugières Laurence , Brecht Ines B. , Thomas‐Teinturier Cécile , Fresneau Brice , Surun Aurore , Ferrari Andrea , Bisogno Gianni , Orbach Daniel
Published: June 2021

Adrenocortical tumours (ACTs) are rare during childhood. A complete surgical resection provides the best chance of cure, but the role and efficacy of the adjuvant therapy are still controversial. Various histologic criteria of malignancy for ACTs adopted in children do not facilitate comparative studies and are not completely shared. Therefore, a sharp demarcation between benign and malignant lesions has not been recognised, making it difficult to identify who potentially needs perioperative therapy. This manuscript presents the internationally harmonised recommendations for the diagnosis and treatment of ACTs in children and adolescents, established by the European Cooperative Study Group for Paediatric Rare Tumours (EXPeRT) group within the EU‐funded project PARTNER (Paediatric Rare Tumours Network ‐ European Registry).
Salivary gland carcinoma in children and adolescents: The EXPeRT/PARTNER diagnosis and treatment recommendations
Authors: Surun Aurore , Schneider Dominik T. , Ferrari Andrea , Stachowicz‐Stencel Teresa , Rascon Jelena , Synakiewicz Anna , Agaimy Abbas , Martinova Kata , Kachanov Denis , Roganovic Jelena , Bien Ewa , Bisogno Gianni , Brecht Ines B. , Kolb Frédéric , Thariat Juliette , Moya‐Plana Antoine , Orbach Daniel
Published: June 2021

Salivary gland carcinomas (SGCs) are rare during childhood and adolescence. Consequently, no standardized recommendations for the diagnosis and therapeutic management of pediatric SGC are available, and pediatric oncologists and surgeons generally follow adult guidelines. Complete surgical resection with adequate margins constitutes the cornerstone of treatment. However, the indications and modalities of adjuvant therapy remain controversial and may be challenging in view of the potential long‐term toxicities in the pediatric population. This paper presents the consensus recommendations for the diagnosis and treatment of children and adolescents with SGCs, established by the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT) within the EU‐funded PARTNER project (Paediatric Rare Tumours Network ‐ European Registry).
Influence of the reinforcement on prepreg tack
Authors: Mbotto Tonye Desire , Buet Gautier Karine
Published: June 2021

In composite manufacturing processes, such as automated placement technologies, it is essential to master the tackiness of thermoset prepregs. Obviously, the resin is responsible of this character, however the present experimental work aims at highlighting the influence of the textile reinforcement. A rheometer is used to carry out a probe‐tack test on several industrial carbon/epoxy prepregs. The results are interpreted in a phenomenological point of view, and the relationship between the failure modes and the shape of the stress–displacement curve is established. Thus, it is shown that textile reinforcement plays a crucial role in tack properties, by means of its organization (fabric or UD), thickness, or the roughness it induces.
Major bleeding in users of direct oral anticoagulants in atrial fibrillation: A pooled analysis of results from multiple population‐based cohort studies
Authors: van den Ham Hendrika A. , Souverein Patrick C. , Klungel Olaf H. , Platt Robert W. , Ernst Pierre , Dell'Aniello Sophie , Schmiedl Sven , Grave Birgit , Rottenkolber Marietta , Huerta Consuelo , Martín Merino Elisa , León‐Muñoz Luz M. , Montero Dolores , Andersen Morten , Aakjær Mia , De Bruin Marie L. , Gardarsdottir Helga
Published: June 2021

Objective

To establish the risk of major bleeding in direct oral anticoagulant (DOAC) users (overall and by class) versus vitamin K antagonist (VKA) users, using health care databases from four European countries and six provinces in Canada.

Methods

A retrospective cohort study was performed according to a similar protocol. First‐users of VKAs or DOACs with a diagnosis of non‐valvular atrial fibrillation (NVAF) were included. The main outcome of interest was major bleeding and secondary outcomes included gastrointestinal (GI) bleeding and intracranial haemorrhage (ICH). Incidence rates of events per 1000 person years were calculated. Hazard ratios (HRs) and 95% confidence intervals (95% CI) were estimated using a Cox proportional hazard regression model. Exposure and confounders were measured and analysed in a time‐dependant way. Risk estimates were pooled using a random effect model.

Results

421 523 patients were included. The risk of major bleeding for the group of DOACs compared to VKAs showed a pooled HR of 0.94 (95% CI: 0.87–1.02). Rivaroxaban showed a modestly increased risk (HR 1.11, 95% CI: 1.06–1.16). Apixaban and dabigatran showed a decreased risk of respectively HR 0.76 (95% CI: 0.69–0.84) and HR 0.85 (95% CI: 0.75–0.96).

Conclusions

This study confirms that the risk of major bleeding of DOACs compared to VKAs is not increased when combining all DOACs. However, we observed a modest higher risk of major bleeding for rivaroxaban, whereas for apixaban and dabigatran lower risks of major bleeding were observed compared to VKAs.
Aza‐Michaelsilicone cure is accelerated byβ‐hydroxyalkylesters
Authors: Lu Guanhua , Yepremyan Akop , Godfrey Simon , Mohr Corinne , Herrlein Mathias , Brook Michael A.
Published: June 2021

The aza‐Michael reaction is proving to be a practical, catalyst free method by which a variety of polymers, including silicones, can be cured. However, its adoption may be compromised by slow cure rates; for many applications is it not practical to accelerate cure by heating. OH groups on the amine, acrylate partner or solvent are known to lead to accelerated rates of aza‐Michael reactions. The impact of the location of OH groups on reaction partners is demonstrated using both small molecules and small molecules plus telechelic silicones. While all OH groups are shown to increase reaction rates, a special enhancement is provided by β‐hydroxyalkyl acrylate esters, which have significantly higher rates of reaction than simple acrylates per se, and yet higher reactivities in hydroxylic media. Using this motif, in the absence of solvents, silicone elastomer cure based on the β‐hydroxyalkyl acrylate motif is facile and complete in less than 30 min at room temperature.
Comparison of the reactivity of isomeric 2H‐ and 3H‐naphthopyran mechanophores
Authors: Osler Skylar K. , McFadden Molly E. , Robb Maxwell J.
Published: June 2021

Naphthopyrans are molecular switches that produce highly colored merocyanine dyes upon photochemical or mechanochemical activation in polymers. The mechanochromic behavior of these molecular force probes enables the straightforward visualization of stress and/or strain in materials. To date, research on the mechanochemistry of naphthopyran has largely focused on the 3H‐naphtho[2,1‐b]pyran (3H) scaffold, whereas isomeric 2H‐naphtho[1,2‐b]pyrans (2H) exhibit complementary properties as suggested from their photochemical reactivity. Here we directly compare the reactivity of two isomeric 2H‐ and 3H‐naphthopyran mechanophores in solution‐phase ultrasonication experiments and in crosslinked polydimethylsiloxane elastomers subjected to uniaxial tensile deformation. The prototypical 3H‐naphthopyran mechanophore produces a yellow merocyanine dye that reverts quickly, while the 2H‐naphthopyran mechanophore generates a red merocyanine dye that reverts significantly slower. The trends in absorption and reversion measured in solution are also reflected in solid polymeric materials activated in tension. Building on recent research into substituent effects, this study identifies naphthopyran isomerism as a simple lever for modulating the mechanochromic properties of the naphthopyran mechanophore used in the development of force‐responsive polymers.
Overcoming the Inhibition Effects of Citrate: Precipitation of Ferromagnetic Magnetite Nanoparticles with Tunable Morphology, Magnetic Properties, and Surface Charge via Ferrous Citrate Oxidation
Authors: Granath Tim , Mandel Karl , Löbmann Peer
Published: June 2021

This study demonstrates how the method of thermally assisted oxidative precipitation in water can be opened for—the so far neglected—metal organic iron(II) complexes (herein: citrate) in order to obtain, in one step, ferromagnetic magnetite nanoparticles, possessing essential ligand properties. Based on a dedicated analysis of the specific precursor in combination with the consideration of known properties of the ligand, it is possible to identify existing inhibition‐attributes of the iron organyl such that these can be overcome. Moreover, they can be exploited in a targeted manner; thus, simply by changing concentrations, a variety of magnetite nanoparticle morphologies with distinct properties can be obtained. In the case of the herein investigated ferrous citrate, three major inhibition effects are identified. While two of them efficiently prevent the formation of magnetite and need to be addressed to be overcome, the third can be exploited to selectively synthesize, for example, relatively stable carboxyl group‐bearing nuclei clusters, exhibiting the properties of magnetically responsive photonic crystals, or relatively large mesocrystals, whose intraparticular magnetic interactions are apparently disturbed.
Synthesis, Characterization and Decomposition of 4‐Diazo‐2,6‐dinitrophenol
Authors: Wang Jian‐long , Cao Cai , Cao Jun‐yan , Yan Yu‐min , Chen Li‐zhen , Cao Duan‐lin
Published: June 2021

A high energetic compound 4‐diazo‐2,6‐dinitrophenol was synthesized by employing one‐pot facile method from 4‐chloro‐3,5‐dinitroaniline. Its structure was characterized by Fourier transform infrared spectroscopy (FT‐IR), elemental analysis (EA), and nuclear magnetic resonance spectroscopy (1H NMR, 13C NMR and 15N NMR). The crystal structure was determined using an X‐ray single crystal diffractometer. The detonation properties of 4‐diazo‐2,6‐dinitrophenol and 6‐diazo‐3,5‐dichloro‐2,4‐dinitrophenol were compared by using Kamlet formula. Besides, the thermal behavior of 4‐diazo‐2,6‐dinitrophenol was analyzed by differential scanning calorimetry (DSC) and accelerating rate calorimeter (ARC), then according to the thermal analysis data, the thermal decomposition kinetics parameters were calculated using the thermal analysis data based on Kissinger method and Flynn‐Wall‐Ozawa method.
The amounts of thermal vibrations and static disorder in protein X‐ray crystallographic B‐factors
Authors: Na Hyuntae , Hinsen Konrad , Song Guang
Published: June 2021

Crystallographic B‐factors provide direct dynamical information on the internal mobility of proteins that is closely linked to function, and are also widely used as a benchmark in assessing elastic network models. A significant question in the field is: what is the exact amount of thermal vibrations in protein crystallographic B‐factors? This work sets out to answer this question. First, we carry out a thorough, statistically sound analysis of crystallographic B‐factors of over 10 000 structures. Second, by employing a highly accurate all‐atom model based on the well‐known CHARMM force field, we obtain computationally the magnitudes of thermal vibrations of nearly 1000 structures. Our key findings are: (i) the magnitude of thermal vibrations, surprisingly, is nearly protein‐independent, as a corollary to the universality for the vibrational spectra of globular proteins established earlier; (ii) the magnitude of thermal vibrations is small, less than 0.1 Å2 at 100 K; (iii) the percentage of thermal vibrations in B‐factors is the lowest at low resolution and low temperature (<10%) but increases to as high as 60% for structures determined at high resolution and at room temperature. The significance of this work is that it provides for the first time, using an extremely large dataset, a thorough analysis of B‐factors and their thermal and static disorder components. The results clearly demonstrate that structures determined at high resolution and at room temperature have the richest dynamics information. Since such structures are relatively rare in the PDB database, the work naturally calls for more such structures to be determined experimentally.
Effects of Surface States on the Green Luminescence in ZnO
Authors: Hu Bei-Chen , Zhou Nan , Zhang Qing-Yu , Ma Chun-Yu
Published: June 2021

The origin of green luminescence (GL) band is an issue long‐term pending in the research of ZnO. Herein, three GL bands (GL1, GL2, and GL‐S bands) are unambiguously identified using the single‐crystal samples with and without a SiOx passivation layer and the polycrystal samples annealed in H2 and O2 atmospheres. Solid evidence demonstrates that the GL1 band can be assigned to the optical emissions from the sample inside and the intensity is decreased with the decrease in temperature. The GL2 and GL‐S bands, which correspond to the structureless and structured GL bands of H‐ and O‐annealed samples, respectively, are found to come from the sample surface and enhanced at low temperatures. Excitons or free electrons and holes generated through interband absorption are found to play an important role in exciting both the GL2 and GL‐S bands. For the light with photon energy lower than the bandgap, however, the GL‐S and GL2 bands exhibit different excitation behaviors. The deficiency of oxygen on the sample surface is confirmed to be the reason resulting in the GL2 band and probably also the reason leading to the GL‐S band.
Preparation of Carbon Nanodots with Ultraviolet Emission by Pulsed Laser Ablation
Authors: Yang Min-Jie , Shi Jian-Xuan , Yin Ying , Shi Chuan-Guo
Published: June 2021

To date, it is still a challenge to acquire carbon nanomaterials with ultraviolet (UV) emission due to the trapping of excited carriers by defect states and surface groups. Herein, a pulsed laser ablation (PLA) method without any post‐treatments is developed to prepare carbon nanodots (CNDs). The cores of the resulting CNDs are graphitic carbon with negligible defects, whereas the surfaces are passivated by simple oxygen‐related groups, which is demonstrated by high‐resolution transmission electron microscope (HRTEM) image, X‐ray diffraction (XRD) pattern, and Raman spectra. Thus, the trapping of excited carriers by defect states and surface groups is substantially suppressed. As a consequence, the CNDs exhibit inherent UV emission of carbon nanostructures. The excitation‐independent UV emission peak contains three sub‐bands at 305, 325, and 335 nm. This work develops an approach for the preparation of UV‐emissive CNDs, which expands the applications of CNDs to UV‐related areas.
Mechanical Properties Analysis on a Novel Negative Poisson's Ratio Voronoi Foam‐Filled Corrugated Tube Under Impact Loading
Authors: Shen Guoyang , Wang Xin , Li Dong
Published: June 2021

A novel negative Poisson's ratio (NPR) foam‐filled corrugated tube, made up of a corrugated tube and NPR isotropic foam core, is established by the finite element method. The 3D NPR isotropic foam core is achieved by using the triaxial compression method on a cubic Voronoi model, which is created based on the Voronoi tessellation technique. The triaxial compression ratio is defined as η. The Poisson's ratio of Voronoi foam decreases sharply and then increases gradually with an increasing η. A minimum Poisson's ratio, −0.076, is obtained when η = 0.2. Moreover, the Voronoi foam‐filled corrugated tube with minimum Poisson's ratio foam core exhibits the highest energy absorption capacity, which is 10.8% higher than that of the Voronoi foam‐filled corrugated tubes with uncompressed foam core.
2D V–VI Binary Nanosheets with Square Lattice: A Theoretical Investigation
Authors: Qiao Xin , Lv Xiaodong , Dong Yinan , Yang Yanping , Li Fengyu
Published: June 2021

It is of paramount importance to explore novel 2D materials with unique structural and physical properties that are promising for application in a specific field. Herein, eleven monolayers with novel square lattice are studied, including S‐SeN2, S‐TeN2, S‐SP2, S‐SeP2, S‐TeP2, S‐SAs2, S‐SeAs2, S‐TeAs2, S‐SSb2, S‐SeSb2, and S‐TeSb2, via first‐principles calculations. Through stability screening, only the S‐SeN2 monolayer, where each Se atom is tetracoordinated with four N atoms, and each N atom bridges two atoms, thus forming a tri‐sublayer structure with square lattice, is verified as a stable 2D crystal because it has high cohesive energy, all positive modes in the phonon spectrum, and structural integrity through the molecular dynamics simulation up to 500 K. It is an indirect‐bandgap semiconductor with high hole mobility, and the direct‐bandgap feature can be easily obtained under external uniaxial compressions or biaxial tensions, which can be applied in electronics, photoelectronics, etc.
Phytochemical characterization and biological properties of two standardized extracts from a non‐psychotropic Cannabis sativa L. cannabidiol (CBD)‐chemotype
Authors: Muscarà Claudia , Smeriglio Antonella , Trombetta Domenico , Mandalari Giuseppina , La Camera Erminia , Grassi Gianpaolo , Circosta Clara
Published: June 2021

The aim of study was to evaluate and compare the phytochemical profile, the antioxidant and antimicrobial properties of two standardized extracts from non‐psychotropic (Δ9‐tetrahydrocannabinol ≤0.2%) Cannabis sativa L. var. fibrante rich in cannabidiol (CBD). The two extracts, namely Cannabis Fibrante Hexane Extract 1 (CFHE1) and Cannabis Fibrante Hexane Extract 2 (CFHE2), were obtained by extraction with acidified hexane from dried flowering tops as such and after hydrodistillation of the essential oil, respectively. Gas chromatographic analysis showed that cannabinoids remained the predominant class of compounds in both extracts (82.56% and 86.38%, respectively), whereas a marked depletion of the terpenes occurred. Moreover, liquid chromatographic analysis highlighted a high titer of cannabidiol acid (CBDA) and CBD in CFHE1 and CFHE2, respectively. Both extracts showed a strong and concentration‐dependent antioxidant activity and a potent antimicrobial activity against both Staphylococcus aureus ATCC 6538 (MIC and MBC of 4.88 μg/ml for CFHE1, and 4.88 and 19.53 μg/ml, respectively, for CFHE2) and methicillin resistant clinical strains (MIC values between 1.22 and 9.77 μg/ml and MBC values between 4.88 and 78.13 μg/ml). Considering this, the obtained results suggest that standardized extracts of C. sativa var. fibrante could find promising applications as novel antimicrobial agents.
Laboratory studies on the effect of adsorbed microbial extracellular polymeric substances on the acidity of selected variable‐charge soils
Authors: Nkoh Jackson Nkoh , Hong Zhi‐Neng , Xu Ren‐Kou
Published: June 2021

Extracellular polymeric substances (EPS) secreted by rhizobacteria are ubiquitous in the environment and can enhance the negative charge of variable‐charge soils. Soil negative charge is directly related to pH buffering capacity (pHBC); it is essential to examine the effect of EPS on soil acidity and pHBC. We investigated the effect of adsorbed EPS on the acidification of five variable‐charge soils in China, which were subjected to different land use: an Oxisol and four Ultisols. Spectroscopic analysis revealed that EPS was specifically adsorbed onto soil surfaces through iron–oxygen–phosphorus/aluminum–oxygen–phosphorus (Fe‐O‐P/Al‐O‐P) bonds formed between phosphoryl groups of EPS and soil Al/Fe oxides. During the formation of Fe‐O‐P/Al‐O‐P bonds, there was ligand exchange between the EPS phosphoryl groups and the surface hydroxyl groups of Fe/Al oxides of the soils. The released OH– played an important role in soil acidity amelioration by the adsorbed EPS through neutralizing H+ and increasing soil suspension pH. After acidification, the pH of EPS‐treated soils was higher than that of the controls. This was attributed to a combined effect of enhanced soil pHBC, and protonation of organic anions (e.g., COO– to COOH) of EPS to decrease the activity of protons. The adsorbed EPS ameliorated prior soil acidity, inhibited new soil acidification, and promoted hydrolysis and re‐adsorption of Al. This was evident as the proportion of organically bound Al and adsorbed hydroxyl Al increased, whereas that of exchangeable Al decreased after EPS adsorption. Therefore, this study can serve as a reference for the molecular design of cost‐effective and environmentally friendly amendments for acid soils.
Peritumoral Microgel Reservoir for Long‐Term Light‐Controlled Triple‐Synergistic Treatment of Osteosarcoma with Single Ultra‐Low Dose
Authors: Yan Jiaqi , Wang Yichuan , Ran Meixin , Mustafa Rawand A. , Luo Huanhuan , Wang Jixiang , Smått Jan‐Henrik , Rosenholm Jessica M. , Cui Wenguo , Lu Yong , Guan Zhenpeng , Zhang Hongbo
Published: June 2021

Local minimally invasive injection of anticancer therapies is a compelling approach to maximize the utilization of drugs and reduce the systemic adverse drug effects. However, the clinical translation is still hampered by many challenges such as short residence time of therapeutic agents and the difficulty in achieving multi‐modulation combination therapy. Herein, mesoporous silica‐coated gold nanorods (AuNR@SiO2) core‐shell nanoparticles are fabricated to facilitate drug loading while rendering them photothermally responsive. Subsequently, AuNR@SiO2 is anchored into a monodisperse photocrosslinkable gelatin (GelMA) microgel through one‐step microfluidic technology. Chemotherapeutic drug doxorubicin (DOX) is loaded into AuNR@SiO2 and 5,6‐dimethylxanthenone‐4‐acetic acid (DMXAA) is loaded in the microgel layer. The osteosarcoma targeting ligand alendronate is conjugated to AuNR@SiO2 to improve the tumor targeting. The microgel greatly improves the injectability since they can be dispersed in buffer and the injectability and degradability are adjustable by microfluidics during the fabrication. The drug release can, in turn, be modulated by multi‐round light‐trigger. Importantly, a single super low drug dose (1 mg kg−1 DOX with 5 mg kg−1 DMXAA) with peritumoral injection generates long‐term therapeutic effect and significantly inhibited tumor growth in osteosarcoma bearing mice. Therefore, this nanocomposite@microgel system can act as a peritumoral reservoir for long‐term effective osteosarcoma treatment.
Accelerating Electron‐Transfer and Tuning Product Selectivity Through Surficial Vacancy Engineering on CZTS/CdS for Photoelectrochemical CO2 Reduction
Authors: Zhou Shujie , Sun Kaiwen , Huang Jialiang , Lu Xinxin , Xie Bingqiao , Zhang Doudou , Hart Judy N. , Toe Cui Ying , Hao Xiaojing , Amal Rose
Published: June 2021

Copper‐based chalcogenides have been considered as potential photocathode materials for photoelectrochemical (PEC) CO2 reduction due to their excellent photovoltaic performance and favorable conduction band alignment with the CO2 reduction potential. However, they suffer from low PEC efficiency due to the sluggish charge transfer kinetics and poor selectivity, resulting from random CO2 reduction reaction pathways. Herein, a facile heat treatment (HT) of a Cu2ZnSnS4(CZTS)/CdS photocathode is demonstrated to enable significant improvement in the photocurrent density (−0.75 mA cm−2 at −0.6 V vs RHE), tripling that of pristine CZTS, as a result of the enhanced charge transfer and promoted band alignment originating from the elemental inter‐diffusion at the CZTS/CdS interface. In addition, rationally regulated CO2 reduction selectivity toward CO or alcohols can be obtained by tailoring the surficial sulfur vacancies by HT in different atmospheres (air and nitrogen). Sulfur vacancies replenished by O‐doping is shown to favor CO adsorption and the CC coupling pathway, and thereby produce methanol and ethanol, whilst the CdS surface with more S vacancies promotes CO desorption capability with higher selectivity toward CO. The strategy in this work rationalizes the interface charge transfer optimization and surface vacancy engineering simultaneously, providing a new insight into PEC CO2 reduction photocathode design.
Graphene‐Based Hybrid Functional Materials
Authors: Anichini Cosimo , Samorì Paolo
Published: June 2021

Graphene is a 2D material combining numerous outstanding physical properties, including high flexibility and strength, extremely high thermal conductivity and electron mobility, transparency, etc., which make it a unique testbed to explore fundamental physical phenomena. Such physical properties can be further tuned by combining graphene with other nanomaterials or (macro)molecules to form hybrid functional materials, which by design can display not only the properties of the individual components but also exhibit new properties and enhanced characteristics arising from the synergic interaction of the components. The implementation of the hybrid approach to graphene also allows boosting the performances in a multitude of technological applications. This review reports the hybrids formed by graphene combined with other low‐dimensional nanomaterials of diverse dimensionality (0D, 1D, and 2D) and (macro)molecules, with emphasis on the synthetic methods. The most important applications of these hybrids in the fields of sensing, water purification, energy storage, biomedical, (photo)catalysis, and opto(electronics) are also reviewed, with a special focus on the superior performances of these hybrids compared to the individual, nonhybridized components.
Photonic Multilayer Structure Induced High Near‐Infrared (NIR) Blockage as Energy‐Saving Window
Authors: Kim Jiwon , Baek Sangwon , Park Jae Yong , Kim Kwang Ho , Lee Jong‐Lam
Published: June 2021

Energy‐saving window that selectively blocks near‐infrared (NIR) is a promising technology to save energy consumption. However, it is hard to achieve both high transmittance in visible light and high reflectance in NIR for the energy‐saving windows. Here, a TiO2/Ag/TiO2/SiO2/TiO2 multilayer is demonstrated on a glass substrate to selectively block NIR while maintaining high transmittance to visible light. The thickness of a TiO2/Ag/TiO2 structure is first design and optimized; the metal layer reflects NIR and the dielectric layers increase transmittance of visible light with zero reflection condition. To further enhance NIR‐blocking capability, a TiO2 back reflector is implemented with a SiO2 spacer to TiO2/Ag/TiO2 structure. The back reflector can induce additional Fresnel reflection without sacrificing transmittance to visible light. The optimal TiO2 (32 nm)/Ag (22 nm)/TiO2 (30 nm)/SiO2 (100 nm)/TiO2 (110 nm)/glass shows solar energy rejection 89.2% (reflection 86.5%, absorption 2.7%) in NIR, visible transmittance 69.9% and high long‐wave (3 ≤ λ ≤ 20 µm) reflectance > 95%. This proposed visible‐transparent, near‐infrared‐reflecting multilayer film can be applied to the windows of buildings and automobiles to reduce the energy consumption.
Dipole‐Moment Induced Phototaxis and Fuel‐Free Propulsion of ZnO/Pt Janus Micromotors
Authors: He Xiaoli , Jiang Huaide , Li Jianjie , Ma Yanmei , Fu Bi , Hu Chengzhi
Published: June 2021

Light‐driven micromotors have stimulated considerate interests due to their potentials in biomedicine, environmental remediation, or serving as the model system for non‐equilibrium physics of active matter. Simultaneous control over the motion direction and speed of micro/nanomotors is crucial for their functionality but still difficult since Brownian motion always randomizes the orientations. Here, a highly efficient light‐driven ZnO/Pt Janus micromotor capable of aligning itself to illumination direction and exhibiting negative phototaxis at high speeds (up to 32 µm s−1) without the addition of any chemical fuels is developed. A light‐triggered self‐built electric field parallel to the light illumination exists due to asymmetrical surface chemical reactions induced by the limited penetration depth of light along the illumination. The phototactic motion of the motor is achieved through electrophoretic rotation induced by the asymmetrical distribution of zeta potential on the two hemispheres of the Janus micromotor, into alignment with the electric field. Notably, similar phototactic propulsion is also achieved on TiO2/Pt and CdS/Pt micromotors, which presents explicit proof of extending the mechanism of dipole‐moment induced phototactic propulsion in other light‐driven Janus micromotors. Finally, active transportation of yeast cells are achieved by the motor, proving its capability in performing complex tasks.