bluuebunny/crossref_metadata_2025 huggingface dataset:
Statistical Patterns of Ionospheric Convection Derived From Mid‐latitude, High‐Latitude, and Polar SuperDARN HF Radar Observations
Authors: Thomas E. G. , Shepherd S. G.
Published: March 2018

Over the last decade, the Super Dual Auroral Radar Network (SuperDARN) has undergone a dramatic expansion in the Northern Hemisphere with the addition of more than a dozen radars offering improved coverage at mid‐latitudes (50°–60° magnetic latitude) and in the polar cap (80°–90° magnetic latitude). In this study, we derive a statistical model of ionospheric convection (TS18) using line‐of‐sight velocity measurements from the complete network of mid‐latitude, high‐latitude, and polar radars for the years 2010–2016. These climatological patterns are organized by solar wind, interplanetary magnetic field (IMF), and dipole tilt angle conditions. We find that for weak solar wind driving conditions the TS18 model patterns are largely similar to the average patterns obtained using high‐latitude radar data only. For stronger solar wind driving the inclusion of mid‐latitude radar data at the equatorward extent of the ionospheric convection can increase the measured cross‐polar cap potential (ΦPC) by as much as 40%. We also derive an alternative model organized by the Kp index to better characterize the statistical convection under a range of magnetic activity conditions. These Kp patterns exhibit similar IMF By dependencies as the TS18 model results and demonstrate a linear increase in ΦPC with increasing Kp for a given IMF orientation. Overall, the mid‐latitude radars provide a better specification of the flows within the nightside Harang reversal region for moderate to strong solar wind driving or geomagnetic activity, while the polar radars improve the quality of velocity measurements in the deep polar cap under all conditions.
Monitoring frequency of intra‐fraction patient motion using the ExacTrac system for LINAC‐based SRS treatments
Authors: Lewis Benjamin C. , Snyder William J. , Kim Siyong , Kim Taeho
Published: March 2018

Purpose

The aim of this study was to investigate the intra‐fractional patient motion using the ExacTrac system in LINAC‐based stereotactic radiosurgery (SRS).

Method

A retrospective analysis of 104 SRS patients with kilovoltage image‐guided setup (Brainlab ExacTrac) data was performed. Each patient was imaged pre‐treatment, and at two time points during treatment (1st and 2nd mid‐treatment), and bony anatomy of the skull was used to establish setup error at each time point. The datasets included the translational and rotational setup error, as well as the time period between image acquisitions. After each image acquisition, the patient was repositioned using the calculated shift to correct the setup error. Only translational errors were corrected due to the absence of a 6D treatment table. Setup time and directional shift values were analyzed to determine correlation between shift magnitudes as well as time between acquisitions.

Results

The average magnitude translation was 0.64 ± 0.59 mm, 0.79 ± 0.45 mm, and 0.65 ± 0.35 mm for the pre‐treatment, 1st mid‐treatment, and 2nd mid‐treatment imaging time points. The average time from pre‐treatment image acquisition to 1st mid‐treatment image acquisition was 7.98 ± 0.45 min, from 1st to 2nd mid‐treatment image was 4.87 ± 1.96 min. The greatest translation was 3.64 mm, occurring in the pre‐treatment image. No patient had a 1st or 2nd mid‐treatment image with greater than 2 mm magnitude shifts.

Conclusion

There was no correlation between patient motion over time, in direction or magnitude, and duration of treatment. The imaging frequency could be reduced to decrease imaging dose and treatment time without significant changes in patient position.
Physical validation of UF‐RIPSA: A rapid in‐clinic peak skin dose mapping algorithm for fluoroscopically guided interventions
Authors: Borrego David , Marshall Emily L. , Tran Trung , Siragusa Daniel A. , Bolch Wesley E.
Published: March 2018

Purpose

The purpose of this study was to experimentally validate UF‐RIPSA, a rapid in‐clinic peak skin dose mapping algorithm developed at the University of Florida using optically stimulated luminescent dosimeters (OSLDs) and tissue‐equivalent phantoms.

Methods

The OSLDs used in this study were InLightTM Nanodot dosimeters by Landauer, Inc. The OSLDs were exposed to nine different beam qualities while either free‐in‐air or on the surface of a tissue equivalent phantom. The irradiation of the OSLDs was then modeled using Monte Carlo techniques to derive correction factors between free‐in‐air exposures and more complex irradiation geometries. A grid of OSLDs on the surface of a tissue equivalent phantom was irradiated with two fluoroscopic x ray fields generated by the Siemens Artis zee bi‐plane fluoroscopic unit. The location of each OSLD within the grid was noted and its dose reading compared with UF‐RIPSA results.

Results

With the use of Monte Carlo correction factors, the OSLD's response under complex irradiation geometries can be predicted from its free‐in‐air response. The predicted values had a percent error of −8.7% to +3.2% with a predicted value that was on average 5% below the measured value. Agreement within 9% was observed between the values of the OSLDs and RIPSA when irradiated directly on the phantom and within 14% when the beam first traverses the tabletop and pad.

Conclusions

The UF‐RIPSA only computes dose values to areas of irradiated skin determined to be directly within the x ray field since the algorithm is based upon ray tracing of the reported reference air kerma value, with subsequent corrections for air‐to‐tissue dose conversion, x ray backscatter, and table/pad attenuation. The UF‐RIPSA algorithm thus does not include the dose contribution of scatter radiation from adjacent fields. Despite this limitation, UF‐RIPSA is shown to be fairly robust when computing skin dose to patients undergoing fluoroscopically guided interventions.
Fully automated searching for the optimal VMAT jaw settings based on Eclipse Scripting Application Programming Interface (ESAPI) and RapidPlan knowledge‐based planning
Authors: Huang Yuliang , Yue Haizhen , Wang Meijiao , Li Sha , Zhang Jian , Liu Zhuolun , Zhang Yibao
Published: March 2018

Purpose

Eclipse treatment planning system has not been able to optimize the jaw positions for Volumetric Modulated Arc Therapy (VMAT). The arbitrary and planner‐dependent jaw placements define the maximum field size within which multi‐leaf‐collimator (MLC) sequences can be optimized to modulate the beam. Considering the mechanical constraints of MLC transitional speed and range, suboptimal X jaw settings may impede the optimization or undermine the deliverability. This work searches optimal VMAT jaw settings automatically based on Eclipse Scripting Application Programming Interface (ESAPI) and RapidPlan knowledge‐based planning.

Methods and materials

Using an ESAPI script, the X jaws of rectal VMAT plans were initially set to conform the planning‐target‐volume (PTV), and were gradually extended toward the isocenter (PTV center) in 5–7 mm increments. Using these jaw pairs, 592 plans were automatically created for 10 patients and quantitatively evaluated using a comprehensive scoring function. A published RapidPlan model was evoked by ESAPI to generate patient‐specific optimization objectives without manual intervention. All candidate plans were first stored as text files to save storage space, and only the best, worst, and conformal plans were consequently recreated for comparison.

Results

Although RapidPlan estimates dose‐volume histogram (DVH) based on individual anatomy, the geometry‐based expected dose (GED) algorithm does not recognize different jaw settings but uses PTV‐conformal jaws as default; hence, identical DVHs were observed regardless of planner‐defined jaws. Therefore, ESAPI finalized dose‐volume calculation and eliminated the plans with unacceptable hotspots before comparison. The plan quality varied dramatically with different jaw settings. Trade‐offs among different organs‐at‐risk (OARs) were collectively considered by the proposed scoring method, which identified the best and worst plans correctly. The plans using conformal jaws were neither the best nor the worst of all candidates.

Conclusions

VMAT plans using optimal jaw locations can be created automatically using ESAPI and RapidPlan. Conformal jaws are not the optimal choice.
Quantification of beam steering with an ionization chamber array
Authors: Gao Song , Balter Peter A. , Tran Benjamin , Rose Mark , Simon William E.
Published: March 2018

Routine quality assurance for linear accelerators (linacs) usually involves verification of beam steering with a water scanning system. We established a beam steering procedure that uses a 2D ionization chamber array (ICA) and verified the equivalence of beam symmetry between the ICA and a water scanning system. The ICA calibration accuracy, reproducibility and stability were evaluated and the uncertainty in the measurement of beam symmetry due to the array calibration was examined. Forty‐five photon beams and 80 electron beams across 7 Varian C‐series and 4 TrueBeam linacs were steered in the radial and transverse directions using an ICA. After beam steering, profiles were re‐measured using the ICA and in‐water using a 3D Scanner (3DS). Beam symmetries measured with the ICA and 3DS were compared by (a) calculating the difference in point‐by‐point symmetry, (b) plotting the histogram distribution of the symmetry differences, and (c) comparing ICA and 3DS differences with their respective Varian symmetry protocol analysis. Array calibrations from five different occurrences (2012 to 2016) over six different beams reproduced within 0.5%. The uncertainty in beam symmetry was less than 0.5% due to the uncertainties in the array calibration. After all beams were steered using the ICA, the point‐by‐point symmetry differences between ICA and 3DS at the off‐axis positions of 20% and 80% of field size for all beam profiles indicated that 95% of point‐by‐point symmetry comparisons agreed within 0.7%, and 100% agreed within 1.0%; after steering with the ICA 97.8% of photon beam profiles (88 of 90) and 97.5% of electron beam profiles (156 of 160) had symmetry within 1% when measured with the 3DS. All photon and electron beam profiles had symmetry within 1.1% and 1.2%, respectively, for profiles measured with the 3DS. Our data demonstrate that a calibrated ICA can be used to steer photon and electron beams achieving beam symmetry within 1% when re‐measured with a 3D water scanning system.
Genomic analysis identifies masqueraders of full‐term cerebral palsy
Authors: Takezawa Yusuke , Kikuchi Atsuo , Haginoya Kazuhiro , Niihori Tetsuya , Numata‐Uematsu Yurika , Inui Takehiko , Yamamura‐Suzuki Saeko , Miyabayashi Takuya , Anzai Mai , Suzuki‐Muromoto Sato , Okubo Yukimune , Endo Wakaba , Togashi Noriko , Kobayashi Yasuko , Onuma Akira , Funayama Ryo , Shirota Matsuyuki , Nakayama Keiko , Aoki Yoko , Kure Shigeo
Published: March 2018

Objective

Cerebral palsy is a common, heterogeneous neurodevelopmental disorder that causes movement and postural disabilities. Recent studies have suggested genetic diseases can be misdiagnosed as cerebral palsy. We hypothesized that two simple criteria, that is, full‐term births and nonspecific brain MRI findings, are keys to extracting masqueraders among cerebral palsy cases due to the following: (1) preterm infants are susceptible to multiple environmental factors and therefore demonstrate an increased risk of cerebral palsy and (2) brain MRI assessment is essential for excluding environmental causes and other particular disorders.

Methods

A total of 107 patients—all full‐term births—without specific findings on brain MRI were identified among 897 patients diagnosed with cerebral palsy who were followed at our center. DNA samples were available for 17 of the 107 cases for trio whole‐exome sequencing and array comparative genomic hybridization. We prioritized variants in genes known to be relevant in neurodevelopmental diseases and evaluated their pathogenicity according to the American College of Medical Genetics guidelines.

Results

Pathogenic/likely pathogenic candidate variants were identified in 9 of 17 cases (52.9%) within eight genes: CTNNB1, CYP2U1, SPAST, GNAO1, CACNA1A, AMPD2, STXBP1, and SCN2A. Five identified variants had previously been reported. No pathogenic copy number variations were identified. The AMPD2 missense variant and the splice‐site variants in CTNNB1 and AMPD2 were validated by in vitro functional experiments.

Interpretation

The high rate of detecting causative genetic variants (52.9%) suggests that patients diagnosed with cerebral palsy in full‐term births without specific MRI findings may include genetic diseases masquerading as cerebral palsy.
Antibodies against cell adhesion molecules and neural structures in paraneoplastic neuropathies
Authors: Siles Ana M. , Martínez‐Hernández Eugenia , Araque Josefa , Diaz‐Manera Jordi , Rojas‐Garcia Ricard , Gallardo Eduard , Illa Isabel , Graus Francesc , Querol Luis
Published: March 2018

Objective

Paraneoplastic neurological syndromes (PNS) are rare neurological disorders in which ectopic expression of neural antigens by a tumor results in an autoimmune attack against the nervous system. Onconeural antibodies not only guide PNS diagnosis but may also help detecting underlying malignancies. Our project aims to uncover new potential antibodies in paraneoplastic neuropathies (PN).

Methods

Thirty‐four patients fulfilling diagnostic criteria of possible (n = 9; 26.5%) and definite (n = 25; 73.5%) PN without onconeural antibodies and 28 healthy controls were included in our study. Sera were tested for known antibodies against neural cell adhesion molecules and screened for novel IgG and IgM reactivities against nerve components: dorsal root ganglia (DRG) neurons, motor neurons, and Schwann cells. Patients showing autoantibodies against any of these cell types were used for immunoprecipitation (IP) studies.

Results

Overall, 9 (26.5%) patients showed significant reactivity against DRG neurons, motor neurons, or Schwann cells, whereas 5 (17.9%) healthy controls only showed moderate reactivity. Compared with control sera, serum samples from patients with paraneoplastic sensory‐motor neuropathies had a higher frequency of IgM antibodies against Schwann cells (0% vs. 40%; P = 0.0028). No novel antigens were identified from our IP experiments. Antibodies against the neural adhesion molecules CNTN1, NF155, NF140, NF186, NCAM1, L1CAM, and the CNTN1/CASPR1 complex were not detected in patients with PN. One (2.9%) patient with CIDP and thymoma had CASPR2 antibodies.

Interpretation

Almost 30% of patients with PN harbor antibodies targeting neural structures, suggesting that novel neoplasm‐associated antigens remain to be discovered.
Gout Severity, Socioeconomic Status, and Work Absence: A Cross‐Sectional Study in Primary Care
Authors: Bowen‐Davies Zachary , Muller Sara , Mallen Christian D. , Hayward Richard A. , Roddy Edward
Published: March 2018

Objective

To examine the association between gout severity and socioeconomic status (SES) and gout severity and work absence.

Methods

Postal questionnaires were sent to adult patients who were registered with 20 general practices and who had consultations regarding gout or had been prescribed allopurinol or colchicine in the preceding 2 years. Gout severity was defined using the following proxy measures: number of attacks, history of oligoarticular/polyarticular attacks, disease duration, and allopurinol use. SES was defined using the English index of multiple deprivation (area level) and using self‐reported educational attainment (individual level). Work absence was defined as taking time off from work in the past 6 months because of gout. Adjusted odds ratios (ORadj; 95% confidence intervals [95% CIs]) were calculated using logistic regression models (adjusted for age, sex, body mass index, gout severity, and comorbidities).

Results

A total of 1,184 completed questionnaires were returned. The mean age of patients was 65.6 years, and 84% were male. Not having attended further education (“further education” is defined as attendance after the statutory minimum school‐leaving age of 16 years) was associated with having had ≥2 gout attacks in the last year (ORadj 0.54 [95% CI 0.36–0.81]) and oligoarticular/polyarticular attacks (ORadj 0.72 [95% CI 0.50–1.05]). Lower area–level deprivation was associated with fewer attacks (≥2) (ORadj 0.71 [95% CI 0.51–0.98]). Work absence was associated with having had ≥2 gout attacks in the last year (ORadj 2.91 [95% CI 1.22– 6.92]), oligoarticular/polyarticular attacks (ORadj 3.10 [95% CI 1.46–6.61]), and shorter disease duration (>18 years) (ORadj 0.13 [95% CI 0.03–0.50]).

Conclusion

Gout severity was associated with individual‐level deprivation, countering the historic and negative perception of gout as a “rich man's disease.” The association of gout severity with work absence reinforces the argument for earlier urate‐lowering therapy to prevent attacks from becoming frequent and debilitating.
Introduction of Planar High Pressure Torsion (P‐HPT) for Fabrication of Nanostructured Sheets
Authors: Hohenwarter Anton , Pippan Reinhard
Published: March 2018

A new severe plastic deformation process based on conventional high pressure torsion is introduced. The process, called planar high pressure torsion (P‐HPT), is capable of inducing large shear strains into materials with planar geometries, such as sheets or strips and can basically be implemented on every standard HPT machine. The principles of this technique will be presented and accompanied by a case‐study, where P‐HPT will be applied on a sheet of pure copper with dimensions of 220 × 110 mm2 and a thickness of 0.75 mm. For comparison, the material is deformed by conventional high pressure torsion using standard specimens with a diameter of 8 mm as well. It will be shown that the mechanical properties and microstructure obtained by P‐HPT correspond well to conventional high pressure torsion results.
Highly Boosted Microbial Extracellular Electron Transfer by Semiconductor Nanowire Array with Suitable Energy Level
Authors: Bian Ruixin , Jiang Yan , Wang Yuan , Sun Jian‐Kun , Hu Jinsong , Jiang Lei , Liu Huan
Published: March 2018

Microbial extracellular electron transfer (EET) with high performance and good controllability is always desired in various bioelectric applications. Depending on the redox state, C‐type cytochromes located across the outer membranes (OMCs) mediate EET with different behaviors. Here, by incorporating Sn‐doped In2O3 nanowire array with flat F‐doped In2O3 (FTO), a composite electrode is developed that can highly boost EET by over 60 times at a certain potential of 0.2 V, where normally only limited EET current is observed on a conductive electrode. It is proposed that the underlay FTO with bias 0.2 V promotes EET via OMCs by physical contacting with microbes, while the semiconductor nanowires provide a suitable energy level to facilitate the EET via OMC‐flavins cofactor, breaking the stereotype of the certain redox state of OMCs at a given potential. As a synergistic effect, EET via both OMCs and flavins is highly boosted simultaneously to achieve the dual‐pathway EET, which could be further amplified by the nanostructured topology of the as‐prepared electrode. Moreover, the EET current shows a positive correlation with the nanowire length, showing good controllability. This work provides an applicable method for constructing various highly efficient bioelectric devices.
Giant Thermal Expansion in 2D and 3D Cellular Materials
Authors: Zhu Hanxing , Fan Tongxiang , Peng Qing , Zhang Di
Published: March 2018

When temperature increases, the volume of an object changes. This property was quantified as the coefficient of thermal expansion only a few hundred years ago. Part of the reason is that the change of volume due to the variation of temperature is in general extremely small and imperceptible. Here, abnormal giant linear thermal expansions in different types of two‐ingredient microstructured hierarchical and self‐similar cellular materials are reported. The cellular materials can be 2D or 3D, and isotropic or anisotropic, with a positive or negative thermal expansion due to the convex or/and concave shape in their representative volume elements respectively. The magnitude of the thermal expansion coefficient can be several times larger than the highest value reported in the literature. This study suggests an innovative approach to develop temperature‐sensitive functional materials and devices.
Traceable Nanoparticles with Dual Targeting and ROS Response for RNAi‐Based Immunochemotherapy of Intracranial Glioblastoma Treatment
Authors: Qiao Chenmeng , Yang Jun , Shen Qi , Liu Ruiyuan , Li Yanhui , Shi Yuanjie , Chen Jingli , Shen Yanqin , Xiao Zuobing , Weng Jie , Zhang Xin
Published: March 2018

The chemotherapy of glioblastoma is severely hindered by the immunosuppressive tumor microenvironment, especially the tumor growth factor β (TGF‐β), an immunosuppressive cytokine. In this study, it is proposed to employ RNAi‐based immunomodulation to modify the tumor immune microenvironment and improve the effect of chemotherapy. Herein, a nanotheranostic system (Angiopep LipoPCB(Temozolomide+BAP/siTGF‐β), ALBTA) with dual targeting and ROS response is established for intracranial glioblastoma treatment. The traceable nanoparticles exhibit strong siRNA condensation, high drug loading efficiency, good serum stability, and magnetic property. They can efficiently cross the blood–brain barrier and target to glioblastoma cells via receptor‐mediated transcytosis. The zwitterionic lipid (distearoyl phosphoethanol‐amine‐polycarboxybetaine lipid) in ALBTA promotes endosomal/lysosomal escape, and thus enhances the cytotoxicity of temozolomide and improves gene silencing efficiency of siTGF‐β. ALBTA significantly improves the immunosuppressive microenvironment and prolongs the survival time of glioma‐bearing mice. Moreover, ALBTA can be accurately traced by MRI in brain tumors. The study indicates that this immunochemotherapeutic platform can serve as a flexible and powerful synergistic system for treatment with brain tumors as well as other brain diseases in central nervous system.
Near‐Infrared‐Light‐Activatable Nanomaterial‐Mediated Phototheranostic Nanomedicines: An Emerging Paradigm for Cancer Treatment
Authors: Vankayala Raviraj , Hwang Kuo Chu
Published: March 2018

Cancer is one of the most deadly diseases threatening the lives of humans. Although many treatment methods have been developed to tackle cancer, each modality of cancer treatment has its own limitations and drawbacks. The development of minimally invasive treatment modalities for cancers remains a great challenge. Near‐infrared (NIR) light‐activated nanomaterial‐mediated phototherapies, including photothermal and photodynamic therapies, provide an alternative means for spatially and temporally controlled minimally invasive treatments of cancers. Nanomaterials can serve as nanocargoes for the delivery of chemo‐drugs, diagnostic contrast reagents, and organic photosensitizers, and can be used to directly generate heat or reactive oxygen species for the treatment of tumors without the need for organic photosensitizers with NIR‐light irradiation. Here, current progress in NIR‐light‐activated nanomaterial‐mediated photothermal therapy and photodynamic therapy is summarized. Furthermore, the effects of size, shape, and surface functionalities of nanomaterials on intracellular uptake, macrophage clearance, biodistribution, cytotoxicities, and biomedical efficacies are discussed. The use of various types of nanomaterials, such as gold nanoparticles, carbon nanotubes, graphene, and many other inorganic nanostructures, in combination with diagnostic and therapeutic modalities for solid tumors, is briefly reviewed.
Hydroxyl‐Directed Rhodium‐Catalyzed C−H Bond Activation and Cyclization Leading to Naphtho[1,8‐bc]pyran Derivatives and its Analogues
Authors: Yan Kelu , Li Bin , Wang Baiquan
Published: March 2018

Rhodium‐catalyzed C−H activation and cyclization of 1‐naphthols and other related compounds with cyclic 2‐diazo‐1,3‐dione compounds leading to naphtho[1,8‐bc]pyran derivatives and its analogues have been developed. Most of the corresponding products were obtained in good to excellent yields. It offers an alternative approach for the synthesis of useful diverse naphtho[1,8‐bc]pyran derivatives.

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Giant Asymmetric Radiation from an Ultrathin Bianisotropic Metamaterial
Authors: Peng Liang , Wang Kewen , Yang Yihao , Chen Yuntian , Wang Gaofeng , Zhang Baile , Chen Hongsheng
Published: March 2018

Unidirectional radiation is of particular interest in high‐power lasing and optics. Commonly, however, it is difficult to achieve a unidirectional profile in such a system without breaking reciprocity. Recently, assisted by metamaterials without structural symmetry, antennas that radiate asymmetrically have been developed, hence providing the possibility of achieving unidirectionality. Nevertheless, it has been challenging to achieve extremely high radiation asymmetry in such antennas. Here, it is demonstrated that this radiation asymmetry is further enhanced when magnetic plasmons are present in the metamaterials. Experimentally, it is shown that a thin metamaterial with a thickness of ≈λ0/8 can exhibit a forward‐to‐backward emission asymmetry of up to 1:32 without any optimization. The work paves the way for manipulating asymmetric radiation by means of metamaterials and may have a variety of promising applications, such as directional optical and quantum emitters, lasers, and absorbers.
Efficient Planar Perovskite Solar Cells Using Passivated Tin Oxide as an Electron Transport Layer
Authors: Lee Yonghui , Lee Seunghwan , Seo Gabseok , Paek Sanghyun , Cho Kyung Taek , Huckaba Aron J. , Calizzi Marco , Choi Dong‐won , Park Jin‐Seong , Lee Dongwook , Lee Hyo Joong , Asiri Abdullah M. , Nazeeruddin Mohammad Khaja
Published: March 2018

Planar perovskite solar cells using low‐temperature atomic layer deposition (ALD) of the SnO2 electron transporting layer (ETL), with excellent electron extraction and hole‐blocking ability, offer significant advantages compared with high‐temperature deposition methods. The optical, chemical, and electrical properties of the ALD SnO2 layer and its influence on the device performance are investigated. It is found that surface passivation of SnO2 is essential to reduce charge recombination at the perovskite and ETL interface and show that the fabricated planar perovskite solar cells exhibit high reproducibility, stability, and power conversion efficiency of 20%.
The effect of mixing on Co‐precipitation and evolution of microstructure of Cu‐ZnO catalyst
Authors: Jiang Xin , Qin Xiangfei , Ling Chen , Wang Zhiyong , Lu Jiangang
Published: March 2018

The influence of feeding point in conventional stirred tank reactor and flow characteristics in micro‐reactor on the microstructure of Cu‐ZnO catalyst was studied. Cu‐Zn distribution in co‐precipitate was characterized by EDS and Zn fraction in zincian malachite was estimated from the 20
peak shift in XRD pattern. The theory analysis and experimental results, combining with measurement of segregation index, show that the contact pattern and mixing of reactants in precipitation process determine the uniformity of Cu‐Zn distribution in initial co‐precipitates at the micro‐scale. The uniform Cu‐Zn distribution is favorable for the formation of zincian malachite with higher Zn fraction, whereas the uneven distribution could lead to either zincian malachite with lower Zn fraction or aurichalcite‐like nonmalachite. These differences in the precursor structure act on subsequent calcination and reduction, as well as their products. Along this path, mixing affects the evolution of the catalyst microstructure by means of Cu‐Zn distribution. © 2018 American Institute of Chemical Engineers AIChE J, 64: 2647–2654, 2018
Morphology evolution and dynamics of droplet coalescence on superhydrophobic surfaces
Authors: Wang Kai , Liang Qianqing , Jiang Rui , Zheng Yi , Lan Zhong , Ma Xuehu
Published: March 2018

In this work, the coalescence of two equal‐sized water droplets on superhydrophobic surfaces (SHSs) is experimentally investigated. The morphologies of droplet coalescence are observed from side‐view and bottom‐view using high‐speed camera system. The related morphology evolution and dynamics of droplet coalescence are explored. The dynamic behaviors of droplet coalescence on SHSs can be decomposed into liquid bridge growth, contact line evolution, and droplet jumping. The liquid bridge radius is proportional to the square root of time, whereas the dimensionless prefactor is decreased from 1.18 to 0.83 due to the transition of interface curvature. The retraction velocity of the contact line shows limited dependence on initial droplet radii as the retraction dynamics considered here are governed by the capillary–inertial effect. The coalesced droplet finally departs the substrate with a dimensionless jumping velocity of around 0.2. A heuristic argument is made to account for the nearly constant dimensionless jumping velocity. © 2018 American Institute of Chemical Engineers AIChE J, 64: 2913–2921, 2018
A Feasibility Trial of Mental Health First Aid First Nations: Acceptability, Cultural Adaptation, and Preliminary Outcomes
Authors: Crooks Claire V. , Lapp Andrea , Auger Monique , van der Woerd Kim , Snowshoe Angela , Rogers Billie Jo , Tsuruda Samantha , Caron Cassidy
Published: March 2018

The Mental Health First Aid First Nations course was adapted from Mental Health First Aid Basic to create a community‐based, culturally safe and relevant approach to promoting mental health literacy in First Nations contexts. Over 2.5 days, the course aims to build community capacity by teaching individuals to recognize and respond to mental health crises. This feasibility trial utilized mixed methods to evaluate the acceptability, cultural adaptation, and preliminary effectiveness of MHFAFN. Our approach was grounded in community‐based participatory research principles, emphasizing relationship‐driven procedures to collecting data and choice for how participants shared their voices. Data included participant interviews (n = 89), and surveys (n = 91) from 10 groups in four provinces. Surveys contained open‐ended questions, retrospective pre‐post ratings, and a scenario. We utilized data from nine facilitator interviews and 24 facilitator implementation surveys. The different lines of evidence converged to highlight strong acceptability, mixed reactions to the cultural adaptation, and gains in participants’ knowledge, mental health first aid skill application, awareness, and self‐efficacy, and reductions in stigma beliefs. Beyond promoting individual gains, the course served as a community‐wide prevention approach by situating mental health in a colonial context and highlighting local resources and cultural strengths for promoting mental well‐being.
Ammonium Ylide Mediated Cyclization Reactions
Authors: Roiser Lukas , Zielke Katharina , Waser Mario
Published: March 2018

The use of readily accessible ammonium ylides for (asymmetric) transformations, especially cyclization reactions, has received considerable attention over the past two decades. A variety of highly enantioselective protocols to facilitate annulation reactions have recently been introduced as an alternative to other common methods including S‐ylide‐mediated strategies. It is the intention of this short review to provide an introduction to this field by highlighting the potential of ammonium ylides for (asymmetric) cyclization reactions as well as to present the limitations and challenges of these methods.
Morphological variation in the genus Chlorocebus: Ecogeographic and anthropogenically mediated variation in body mass, postcranial morphology, and growth
Authors: Turner Trudy R. , Schmitt Christopher A. , Cramer Jennifer Danzy , Lorenz Joseph , Grobler J. Paul , Jolly Clifford J. , Freimer Nelson B.
Published: March 2018

Objectives

Direct comparative work in morphology and growth on widely dispersed wild primate taxa is rarely accomplished, yet critical to understanding ecogeographic variation, plastic local variation in response to human impacts, and variation in patterns of growth and sexual dimorphism. We investigated population variation in morphology and growth in response to geographic variables (i.e., latitude, altitude), climatic variables (i.e., temperature and rainfall), and human impacts in the vervet monkey (Chlorocebus spp.).

Methods

We trapped over 1,600 wild vervets from across Sub‐Saharan Africa and the Caribbean, and compared measurements of body mass, body length, and relative thigh, leg, and foot length in four well‐represented geographic samples: Ethiopia, Kenya, South Africa, and St. Kitts & Nevis.

Results

We found significant variation in body mass and length consistent with Bergmann's Rule in adult females, and in adult males when excluding the St. Kitts & Nevis population, which was more sexually dimorphic. Contrary to Rensch's Rule, although the South African population had the largest average body size, it was the least dimorphic. There was significant, although very small, variation in all limb segments in support for Allen's Rule. Females in high human impact areas were heavier than those with moderate exposures, while those in low human impact areas were lighter; human impacts had no effect on males.

Conclusions

Vervet monkeys appear to have adapted to local climate as predicted by Bergmann's and, less consistently, Allen's Rule, while also responding in predicted ways to human impacts. To better understand deviations from predicted patterns will require further comparative work in vervets.
Questioning the Recent Observation of Quantum Hawking Radiation
Authors: Leonhardt Ulf
Published: March 2018

A recent article [J. Steinhauer, Nat. Phys. 2016, 12, 959] has reported the observation of quantum Hawking radiation and its entanglement in an analogue black hole. Here, the published evidence, its consistency with theoretical bounds, and the statistical significance of the results are analyzed. The analysis raises severe doubts on the observation of Hawking radiation.
Geometric Structures of Fractional Dynamical Systems in Non‐Riemannian Space: Applications to Mechanical and Electromechanical Systems
Authors: Yajima Takahiro , Nagahama Hiroyuki
Published: March 2018

Based on a non‐Riemannian treatment of geometric objects, the geometric structures of fractional‐order dynamical systems are investigated. A fractional derivative describes non‐local effects across a space or a history encoded in memory features of the system. A system of fractional‐order differential equations is formulated in film space that includes fictitious forces. Film space is a geometric space whose coordinates comprise time, and the geometric quantities vary in time. Fractional‐order torsion tensors that appear are related to the dissipated energy and the energy conversions between subsystems and power of the system. The geometric treatment is then applied to damped‐harmonic and fractional oscillators and the hybrid electromechanical Rikitake system. The damped‐harmonic oscillator is characterized by two torsion tensors, whereas the fractional oscillator is characterized by one torsion tensor. Herein, the fractional order of the derivative of the metric tensor is used to characterize the damping of the fractional oscillator. The energy conversions between electromechanical subsystems in the Rikitake system are characterized by the torsion tensor. These results suggest that the non‐Riemannian geometric objects can represent the non‐local properties of fractional‐order dynamical systems.
Comment on “Questioning the Recent Observation of Quantum Hawking Radiation” [Ann. Phys. (Berlin) 2018, 530, 1700114]
Authors: Steinhauer Jeff
Published: March 2018

The observation of quantum Hawking radiation and its entanglement in an analogue black hole was recently reported. A subsequent article presented critical comments of the study. The article suffers from technical difficulties which invalidate its claims. These include the misunderstanding of a simple Fourier transform, the unnecessary modification of experimental data, and the assertion that the experiment measured a strictly‐zero population.
Local Atomic Arrangements and Band Structure of Boron Carbide
Authors: Rasim Karsten , Ramlau Reiner , Leithe‐Jasper Andreas , Mori Takao , Burkhardt Ulrich , Borrmann Horst , Schnelle Walter , Carbogno Christian , Scheffler Matthias , Grin Yuri
Published: March 2018

Boron carbide, the simple chemical combination of boron and carbon, is one of the best‐known binary ceramic materials. Despite that, a coherent description of its crystal structure and physical properties resembles one of the most challenging problems in materials science. By combining ab initio computational studies, precise crystal structure determination from diffraction experiments, and state‐of‐the‐art high‐resolution transmission electron microscopy imaging, this concerted investigation reveals hitherto unknown local structure modifications together with the known structural alterations. The mixture of different local atomic arrangements within the real crystal structure reduces the electron deficiency of the pristine structure CBC+B12, answering the question about electron precise character of boron carbide and introducing new electronic states within the band gap, which allow a better understanding of physical properties.
Transport of Nucleoside Triphosphates into Cells by Artificial Molecular Transporters
Authors: Zawada Zbigniew , Tatar Ameneh , Mocilac Pavle , Buděšínský Miloš , Kraus Tomáš
Published: March 2018

Chemically modified nucleoside triphosphates (NTPs) are widely exploited as unnatural metabolites in chemical biology and medicinal chemistry. Because anionic NTPs do not permeate cell membranes, their corresponding neutral precursors are employed in cell‐based assays. These precursors become active metabolites after enzymatic conversion, which often proceeds insufficiently. Here we show that metabolically‐active NTPs can be directly transported into eukaryotic cells and bacteria by the action of designed synthetic nucleoside triphosphate transporters (SNTTs). The transporter is composed of a receptor, which forms a non‐covalent complex with a triphosphate anion, and a cell‐penetrating agent, which translocates the complex across the plasma membrane. NTP is then released from the complex in the intracellular milieu and accumulates in nuclei and nucleoli in high concentration. The transport of NTPs proceeds rapidly (seconds to minutes) and selectively even in the presence of other organic anions. We demonstrate that this operationally simple and efficient means of transport of fluorescently labelled NTPs into cells can be used for metabolic labeling of DNA in live cells.
Thermo‐Driven Controllable Emulsion Separation by a Polymer‐Decorated Membrane with Switchable Wettability
Authors: Zhang Weifeng , Liu Na , Zhang Qingdong , Qu Ruixiang , Liu Yanan , Li Xiangyu , Wei Yen , Feng Lin , Jiang Lei
Published: March 2018

A thermoresponsive Poly(N‐isopropylacrylamide) (PNIPAAm)‐modified nylon membrane was fabricated via hydrothermal route. Combining rough structure, proper pore size, and thermoresponsive wettability, the membrane can separate at least 16 types of stabilized oil‐in‐water and water‐in‐oil emulsions at different temperatures. Below the LCST (ca. 25 °C), the material exhibits hydrophilicity and underwater superoleophobicity, which can be used for the separation of various kinds of oil‐in‐water emulsions. Above the LCST (ca. 45 °C), the membrane shows the opposite property with high hydrophobicity and superoleophilicity, and it can then separate stabilized water‐in‐oil emulsions. The material exhibits excellent recyclability and high separation efficiency for various kinds of emulsions and the hydrothermal method is facile and low‐cost. The membrane shows good potential in real situations such as on‐demand oil‐spill cleanup, industrial wastewater treatment, remote operation of oil/water emulsion separation units, and fuel purification.
Dynamic Changes in the Structure, Chemical State and Catalytic Selectivity of Cu Nanocubes during CO2 Electroreduction: Size and Support Effects
Authors: Grosse Philipp , Gao Dunfeng , Scholten Fabian , Sinev Ilya , Mistry Hemma , Roldan Cuenya Beatriz
Published: March 2018

In situ and operando spectroscopic and microscopic methods were used to gain insight into the correlation between the structure, chemical state, and reactivity of size‐ and shape‐controlled ligand‐free Cu nanocubes during CO2 electroreduction (CO2RR). Dynamic changes in the morphology and composition of Cu cubes supported on carbon were monitored under potential control through electrochemical atomic force microscopy, X‐ray absorption fine‐structure spectroscopy and X‐ray photoelectron spectroscopy. Under reaction conditions, the roughening of the nanocube surface, disappearance of the (100) facets, formation of pores, loss of Cu and reduction of CuOx species observed were found to lead to a suppression of the selectivity for multi‐carbon products (i.e. C2H4 and ethanol) versus CH4. A comparison with Cu cubes supported on Cu foils revealed an enhanced morphological stability and persistence of CuI species under CO2RR in the former samples. Both factors are held responsible for the higher C2/C1 product ratio observed for the Cu cubes/Cu as compared to Cu cubes/C. Our findings highlight the importance of the structure of the active nanocatalyst but also its interaction with the underlying substrate in CO2RR selectivity.
Singlet Oxygen and the Origin of Oxygen Functionalities on the Surface of Carbon Electrodes
Authors: Chaisiwamongkhol Korbua , Batchelor‐McAuley Christopher , Palgrave Robert G. , Compton Richard G.
Published: March 2018

The generation of oxygen‐containing functionalities on pristine carbon surfaces is investigated and shown to be light sensitive, specifically to infra‐red radiation. A mechanistic route involving singlet oxygen, 1O2, is proposed and evidenced.
Another Unprecedented Wieland Mechanism Confirmed: Hydrogen Formation from Hydrogen Peroxide, Formaldehyde, and Sodium Hydroxide
Authors: Czochara Robert , Litwinienko Grzegorz , Korth Hans‐Gert , Ingold Keith U.
Published: March 2018

In 1923, Wieland and Wingler reported that in the molecular hydrogen producing reaction of hydrogen peroxide with formaldehyde in basic solution, free hydrogen atoms (H.) are not involved. They postulated that bis(hydroxymethyl)peroxide, HOCH2OOCH2OH, is the intermediate, which decomposes to yield H2 and formate, proposing a mechanism that would nowadays be considered as a “concerted process”. Since then, several other (conflicting) “mechanisms” have been suggested. Our NMR and Raman spectroscopic and kinetic studies, particularly the determination of the deuterium kinetic isotope effect (DKIE), now confirm that in this base‐dependent reaction, both H atoms of H2 derive from the CH2 hydrogen atoms of formaldehyde, and not from the OH groups of HOCH2OOCH2OH or from water. Quantum‐chemical CBS‐QB3 and W1BD computations show that H2 release proceeds through a concerted process, which is strongly accelerated by double deprotonation of HOCH2OOCH2OH, thereby ruling out a free radical pathway.
Singly and Doubly 1,2‐Phenylene‐Inserted Porphyrin Arch‐Tape Dimers: Synthesis and Highly Contorted Structures
Authors: Fukui Norihito , Osuka Atsuhiro
Published: March 2018

Singly and doubly 1,2‐phenylene‐inserted NiII porphyrin arch‐tape dimers 3 and 9 were synthesized from the corresponding β‐to‐β 1,2‐phenylene‐bridged NiII porphyrin dimers 5 and 11 via Ni0‐mediated reductive cyclization and DDQ/Sc(OTf)3‐promoted oxidative cyclization as key steps, respectively. Owing to the fused eight‐membered ring(s), 3 showed a more contorted structure than those of previously reported arch‐tape dimers 2 a and 2 b possessing a fused seven‐membered ring. Furthermore, 9 displayed much larger molecular contortion. As the molecular contortion increases, the Q band of the absorption spectrum becomes more red‐shifted and the electrochemcial HOMO–LUMO gap becomes smaller, reaching at 1294 nm and 0.77 eV in 9, respectively. The effect of molecular contortion on the electronic properties was studied by means of DFT calculations.
Hydrodynamics and separation regimes in a cyclonic–static microbubble flotation column
Authors: Yan Xiaokang , Meng Shiqi , Wang Ai , Wang Lijun , Cao Yijun
Published: March 2018

A cyclonic–static microbubble flotation column (FCSMC) operates under multiple flow regimes, which significantly improves recovery and selectivity. To understand the flow behavior and separation in an FCSMC, unsteady gas–fluid flow numerical simulations are performed. The computational fluid dynamics model is validated against the particle image velocimetry measurements applied to a lab‐scale FCSMC. Hydrodynamic features and qualitative mineralization characteristics are studied. Global analysis reveals that an FCSMC operates under plug flow, swirling flow, and jet and pipe flow regimes along the pulp flow direction, through which the flow velocity, gas holdup, and turbulence gradually increase. This gradual intensification should overcome the mineral's decreased floatability over time. Local hydrodynamic and separation analyses indicate that the gas and liquid in the column unit move axially in opposite directions with very‐low velocities, which results in countercurrent collisions, a low recovery capacity and high selectivity. In the cyclone unit, both phases rotate clockwise with high tangential, low radial, and axial velocities. Both axial and radial velocities of the gas and liquid have different magnitudes and opposite directions, which indicates the countercurrent collisions in the axial and radial directions. The density‐based separation of tailings and surface flotation of middling takes place in this zone. In the pipe unit, the flow velocity, gas holdup, and turbulence are the highest of the entire FCSMC. Minerals with the lowest floatability are recovered in this zone, but the selectivity is low. Overall, the presence of multiple flow regimes allows the integration of multiple mineralization steps in one column and provides conditions for overcoming the decreased mineral floatability over flotation time, improving both mineralization and selectivity.
Electrically insulating ZnOs/ZnOw/silicone rubber nanocomposites with enhanced thermal conductivity and mechanical properties
Authors: Li Chuanbin , Liu Bin , Gao Zhaodongfang , Wang Huan , Liu Ming , Wang Shan , Xiong Chuanxi
Published: March 2018

In this work, hybrids of surface modified zinc oxide spherical (ZnOs) nanoparticles and tetrapod‐shaped whiskers (ZnOw) were incorporated into the silicon rubber (SR) to prepare the ZnOs/ZnOw/SR nanocomposites. The incorporation of the ZnOs/ZnOw facilitated the formation of three‐dimensional thermally conducting network. It was found that the thermal conductivity of the ZnOs/ZnOw/SR reached up to 1.309 W m−1 K−1 when the ZnOs/ZnOw content was 20 vol % (Vm‐ZnOs:VZnOw = 7:3), which was nearly 6.5 times that of the pristine SR. The dielectric and resistivity measurements showed that the incorporation of the ZnOs/ZnOw hybrids did not cause much change in the electrical properties. In addition, the results show that the tensile strength of ZnOs/ZnOw/SR nanocomposites is higher than that of pristine SR. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46454.