bluuebunny/crossref_metadata_2025 huggingface dataset:
Transiently disordered tails accelerate folding of globular proteins
Authors: Mallik Saurav , Ray Tanaya , Kundu Sudip
Published: June 2017

Numerous biological proteins exhibit intrinsic disorder at their termini, which are associated with multifarious functional roles. Here, we show the surprising result that an increased percentage of terminal short transiently disordered regions with enhanced flexibility (TstDREF) is associated with accelerated folding rates of globular proteins. Evolutionary conservation of predicted disorder at TstDREFs and drastic alteration of folding rates upon point‐mutations suggest critical regulatory role(s) of TstDREFs in shaping the folding kinetics. TstDREFs are associated with long‐range intramolecular interactions and the percentage of native secondary structural elements physically contacted by TstDREFs exhibit another surprising positive correlation with folding kinetics. These results allow us to infer probable molecular mechanisms behind the TstDREF‐mediated regulation of folding kinetics that challenge protein biochemists to assess by direct experimental testing.
A numerical study of the convection triggering and propagation associated with sea breeze circulation over Hainan Island
Authors: Liang Zhaoming , Wang Donghai , Liu Ying , Cai Qinbo
Published: June 2017

Based on high‐resolution numerical simulations, the effects of sea breeze circulation (SBC) on associated convective initiation and propagation over Hainan Island are investigated. The results show that the blocking of synoptic wind on the windward side of the mountains inhibits the occurrence of windward‐side valley breeze and sea breeze. In the context of low mountains, weak synoptic wind not only favors the combination of the SBC with the valley breeze circulation on the leeward side of the mountains but also makes the convergence zone between the synoptic wind and the leeward‐side combined circulation stay near the tops of the mountains, leading to the accumulation of large quantities of water vapor taking place over the mountaintops. The combined effect of enhanced water vapor and high temperatures over the mountaintops can result in the generation of much larger convective available potential energy (CAPE) than the surrounding areas. The coupling of the large CAPE with the considerable converging ascending motion and abundant water vapor near the tops of the mountains promotes the occurrence of a strong convection band (CB) over the mountaintops. During the CB propagation under the steering of synoptic wind, the flow across the CB continuously and strongly opposes the SBC front and the fronts of the Kelvin‐Helmholtz billows behind, resulting in successive and strong lifting motion as well as large quantities of water vapor and high CAPE near these fronts. These lead to an apparent downstream wave‐like propagation of the CB.
Could geoengineering research help answer one of the biggest questions in climate science?
Authors: Wood Robert , Ackerman Thomas , Rasch Philip , Wanser Kelly
Published: June 2017

Anthropogenic aerosol impacts on clouds constitute the largest source of uncertainty in quantifying the radiative forcing of climate, and hinders our ability to determine Earth's climate sensitivity to greenhouse gas increases. Representation of aerosol–cloud interactions in global models is particularly challenging because these interactions occur on typically unresolved scales. Observational studies show influences of aerosol on clouds, but correlations between aerosol and clouds are insufficient to constrain aerosol forcing because of the difficulty in separating aerosol and meteorological impacts. In this commentary, we argue that this current impasse may be overcome with the development of approaches to conduct control experiments whereby aerosol particle perturbations can be introduced into patches of marine low clouds in a systematic manner. Such cloud perturbation experiments constitute a fresh approach to climate science and would provide unprecedented data to untangle the effects of aerosol particles on cloud microphysics and the resulting reflection of solar radiation by clouds. The control experiments would provide a critical test of high‐resolution models that are used to develop an improved representation aerosol–cloud interactions needed to better constrain aerosol forcing in global climate models.
A new solar wind‐driven global dynamic plasmapause model: 1. Database and statistics
Authors: Zhang Xiao‐Xin , He Fei , Lin Rui‐Lin , Fok Mei‐Ching , Katus Roxanne M. , Liemohn Michael W. , Gallagher Dennis L. , Nakano Shinya
Published: June 2017

A large database, possibly the largest plasmapause location database, with 49,119 plasmapause crossing events from the in situ observations and 3957 plasmapause profiles (corresponding to 48,899 plasmapause locations in 1 h magnetic local time (MLT) intervals) from optical remote sensing from 1977 to 2015 by 18 satellites is compiled. The responses of the global plasmapause to solar wind and geomagnetic changes and the diurnal, seasonal, solar cycle variations of the plasmapause are investigated based on this database. It is found that the plasmapause shrinks toward the Earth globally and a clear bulge appears in the afternoon to premidnight MLT sector as the solar wind or geomagnetic conditions change from quiet to disturbed. The bulge is clearer during storm times or southward interplanetary magnetic field. The diurnal variations of the plasmapause are most probably the result of the difference between the magnetic dipole tilt and the Earth's spin axis. The seasonal variations of the plasmapause are characterized by equinox valleys and solstice peaks. It is also found that the plasmapause approaches the Earth during high solar activity and expands outward during low solar activity. This database will help us study and understand the evolution properties of the plasmapause shape and the interaction processes of the plasmasphere, the ring current, and the radiation belts in the magnetosphere.
Ionospheric Alfvén resonator and aurora: Modeling of MICA observations
Authors: Tulegenov B. , Streltsov A. V.
Published: June 2017

We present results from a numerical study of small‐scale, intense magnetic field‐aligned currents observed in the vicinity of the discrete auroral arc by the Magnetosphere‐Ionosphere Coupling in the Alfvén Resonator (MICA) sounding rocket launched from Poker Flat, Alaska, on 19 February 2012. The goal of the MICA project was to investigate the hypothesis that such currents can be produced inside the ionospheric Alfvén resonator by the ionospheric feedback instability (IFI) driven by the system of large‐scale magnetic field‐aligned currents interacting with the ionosphere. The trajectory of the MICA rocket crossed two discrete auroral arcs and detected packages of intense, small‐scale currents at the edges of these arcs, in the most favorable location for the development of the ionospheric feedback instability, predicted by the IFI theory. Simulations of the reduced MHD model derived in the dipole magnetic field geometry with realistic background parameters confirm that IFI indeed generates small‐scale ULF waves inside the ionospheric Alfvén resonator with frequency, scale size, and amplitude showing a good, quantitative agreement with the observations. The comparison between numerical results and observations was performed by “flying” a virtual MICA rocket through the computational domain, and this comparison shows that, for example, the waves generated in the numerical model have frequencies in the range from 0.30 to 0.45 Hz, and the waves detected by the MICA rocket have frequencies in the range from 0.18 to 0.50 Hz.
Ion velocity distributions in dipolarization events: Beams in the vicinity of the plasma sheet boundary
Authors: Birn J. , Chandler M. , Moore T. , Runov A.
Published: June 2017

Using combined MHD/test particle simulations, we further explore characteristic ion velocity distributions in relation to magnetotail reconnection and dipolarization events, focusing on distributions at and near the plasma sheet boundary layer (PSBL). Simulated distributions right at the boundary are characterized by a single earthward beam, as discussed earlier. However, farther inside, the distributions consist of multiple beams parallel and antiparallel to the magnetic field, remarkably similar to recent Magnetospheric Multiscale observations. The simulations provide insight into the mechanisms: the lowest earthward beam results from direct acceleration at an earthward propagating dipolarization front (DF), with a return beam at somewhat higher energy. A higher‐energy earthward beam results from dual acceleration, first near the reconnection site and then at the DF, again with a corresponding return beam resulting from mirroring closer to Earth. Multiple acceleration at the X line or the propagating DF with intermediate bounces may produce even higher‐energy beams. Particles contributing to the lower energy beams are found to originate from the PSBL with thermal source energies, increasing with increasing beam energy. In contrast, the highest‐energy beams consist mostly of particles that have entered the acceleration region via cross‐tail drift with source energies in the suprathermal range.
Deciphering the NH4PbI3 Intermediate Phase for Simultaneous Improvement on Nucleation and Crystal Growth of Perovskite
Authors: Si Haonan , Liao Qingliang , Kang Zhuo , Ou Yang , Meng JingJing , Liu Yichong , Zhang Zheng , Zhang Yue
Published: June 2017

The NH4PbI3‐based phase transformation is realized by simply adding NH4I additive, in order to simultaneously control perovskite nucleation and crystal growth. Regarding the nucleation process, the NH4+ with small ionic radius preferentially diffuses into the [PbI6]4− octahedral layer to form NH4PbI3, which compensates the lack of CH3NH3I (MAI) precipitation. The generation of NH4PbI3 intermediate phase results in extra heterogeneous nucleation sites and reduces the defects derived from the absence of MA+. Regarding the crystal growth process, the cation exchange process between MA+ and NH4+, instead of the MAs directly entering, successfully retards the crystal growth. Such NH4PbI3 consumption process slows down the crystal growth, which effectively improves the perovskite quality with lowered defect density. The cooperation of these two effects eventually leads to the high‐quality perovskite with enlarged grain size, prolonged photoluminescence lifetime, lowered defect density, and increased carrier concentration, as well as the finally enhanced photovoltaic performance. Moreover, NH3 as a byproduct further facilitates the proposed transformation process and no external residue remains even without any post‐treatment. Such methodology of introducing a novel phase transformation to simultaneously control nucleation and crystal growth processes is of universal significance for further devotion in the foreseeable perovskite solar cells (PSCs) evolution.
Skin‐Inspired Multifunctional Autonomic‐Intrinsic Conductive Self‐Healing Hydrogels with Pressure Sensitivity, Stretchability, and 3D Printability
Authors: Darabi Mohammad Ali , Khosrozadeh Ali , Mbeleck Rene , Liu Yuqing , Chang Qiang , Jiang Junzi , Cai Jun , Wang Quan , Luo Gaoxing , Xing Malcolm
Published: June 2017

The advent of conductive self‐healing (CSH) hydrogels, a class of novel materials mimicking human skin, may change the trajectory of the industrial process because of their potential applications in soft robots, biomimetic prostheses, and health‐monitoring systems. Here, the development of a mechanically and electrically self‐healing hydrogel based on physically and chemically cross‐linked networks is reported. The autonomous intrinsic self‐healing of the hydrogel is attained through dynamic ionic interactions between carboxylic groups of poly(acrylic acid) and ferric ions. A covalent cross‐linking is used to support the mechanical structure of the hydrogel. Establishing a fair balance between the chemical and physical cross‐linking networks together with the conductive nanostructure of polypyrrole networks leads to a double network hydrogel with bulk conductivity, mechanical and electrical self‐healing properties (100% mechanical recovery in 2 min), ultrastretchability (1500%), and pressure sensitivity. The practical potential of CSH hydrogels is further revealed by their application in human motion detection and their 3D‐printing performance.
Bilayer PbS Quantum Dots for High‐Performance Photodetectors
Authors: Ren Zhenwei , Sun Jiankun , Li Hui , Mao Peng , Wei Yuanzhi , Zhong Xinhua , Hu Jinsong , Yang Shiyong , Wang Jizheng
Published: June 2017

Due to their wide tunable bandgaps, high absorption coefficients, easy solution processabilities, and high stabilities in air, lead sulfide (PbS) quantum dots (QDs) are increasingly regarded as promising material candidates for next‐generation light, low‐cost, and flexible photodetectors. Current single‐layer PbS‐QD photodetectors suffer from shortcomings of large dark currents, low on–off ratios, and slow light responses. Integration with metal nanoparticles, organics, and high‐conducting graphene/nanotube to form hybrid PbS‐QD devices are proved capable of enhancing photoresponsivity; but these approaches always bring in other problems that can severely hamper the improvement of the overall device performance. To overcome the hurdles current single‐layer and hybrid PbS‐QD photodetectors face, here a bilayer QD‐only device is designed, which can be integrated on flexible polyimide substrate and significantly outperforms the conventional single‐layer devices in response speed, detectivity, linear dynamic range, and signal‐to‐noise ratio, along with comparable responsivity. The results which are obtained here should be of great values in studying and designing advanced QD‐based photodetectors for applications in future flexible optoelectronics.
Nonvolatile Perovskite‐Based Photomemory with a Multilevel Memory Behavior
Authors: Chen Jung‐Yao , Chiu Yu‐Cheng , Li Yen‐Ting , Chueh Chu‐Chen , Chen Wen‐Chang
Published: June 2017

Solution‐processable organic–inorganic hybrid perovskite materials with a wealth of exotic semiconducting properties have appeared as the promising front‐runners for next‐generation electronic devices. Further, regarding its well photoresponsibility, various perovskite‐based photosensing devices are prosperously developed in recent years. However, most exploited devices to date only transiently transduce the optical signals into electrical circuits while under illumination, which necessitates using additional converters to further store the output signals for recording the occurrence of light stimulation. Herein, a nonvolatile perovskite‐based floating‐gate photomemory with a multilevel memory behavior is demonstrated, for which a floating gate comprising a polymer matrix impregnated with perovskite nanoparticles is employed. Owing to the well photoresponsibility introduced by the embedded nanoparticles, the device is enabled to access multiple wavelength response and the functionalities of recording power/time‐dependent illumination under no vertical electrical field. Intriguingly, a nonvolatility of photorecording exceeding three months with a high On/Off current ratio over 104 can be achieved.
Organogelator–Cellulose Composite for Practical and Eco‐Friendly Marine Oil‐Spill Recovery
Authors: Prathap Annamalai , Sureshan Kana M.
Published: June 2017

Marine oil spills pose serious threats to the ecosystem and economy. There is much interest in developing sorbents that can tackle such spills. We have developed a novel sorbent by impregnating cellulose pulp with a sugar‐derived oleogelator, 1,2:5,6‐di‐O‐cyclohexylidene‐mannitol. The gelator molecules mask the surface‐exposed hydroxyl groups of cellulose fibrils by engaging them in H‐bonding and expose their hydrophobic parts making the fibers temporarily hydrophobic (water contact angle 110°). This sorbent absorbs oil effectively, selectively and instantly from oil–water mixtures due to its hydrophobicity. Then the gelator molecules get released uniformly in the oil and later self‐assemble to fibers, as evident from SEM analysis, congealing the oil within the matrix. This hierarchical entrapment of the oil by non‐covalent polymeric fibers within a covalent polymer matrix makes the gel very strong (230‐fold increase in the yield stress) and rigid, making it suitable for practical use.
From Borane to Borylene without Reduction: Ambiphilic Behavior of a Monovalent Silylisonitrile Boron Species
Authors: Arrowsmith Merle , Auerhammer Dominic , Bertermann Rüdiger , Braunschweig Holger , Celik Mehmet Ali , Erdmannsdörfer Julian , Krummenacher Ivo , Kupfer Thomas
Published: June 2017

Deprotonation of [(cAAC)BH2(CN)] provided clean access to the stable boryl anion, [(cAAC)BH(CN)]−. Whereas the addition of soft electrophiles occurred at the nucleophilic boron center, harder silyl electrophiles added to the harder terminal cyano nitrogen. The resulting [(cAAC)BH(CNSiPh3)] species behaved like a silylium boryl nucleophile as well as a neutral silylisonitrile borylene.
Design and in‐situ evaluation of a mixed‐initiative approach to information organization
Authors: Haraty Mona , Wang Zhongyuan , Wang Helen , Iqbal Shamsi , Teevan Jaime
Published: June 2017

Organizing personal information by folders or tags has proved to be effective for finding, remembering, and understanding information. However, past studies have shown that the cost of organization can be too high for some users to be worth the effort. Mixed‐initiative approaches attempt to reduce the burden of manual organization by automatically identifying and suggesting organizational units such as folders to users. However, little is known about how such mixed‐initiative approaches influence users' organizational experiences. In this paper, we explore a mixed‐initiative approach that suggests high‐level organizational units to users to facilitate e‐mail organization. In 2 in‐situ experiments with 34 knowledge workers, we study how our mixed‐initiative approach influenced users' experience with organization. We show that our approach made it easier to create organizational units without negatively affecting recall of those units, and led to the creation of units that otherwise would have not been created. Our findings suggest ways computers and people can most effectively work together to organize information.
Long‐term survival benefit of upfront chemotherapy in patients with newly diagnosed borderline resectable pancreatic cancer
Authors: Shrestha Bikram , Sun Yifei , Faisal Farzana , Kim Victoria , Soares Kevin , Blair Alex , Herman Joseph M. , Narang Amol , Dholakia Avani S. , Rosati Lauren , Hacker‐Prietz Amy , Chen Linda , Laheru Daniel A. , De Jesus‐Acosta Ana , Le Dung T. , Donehower Ross , Azad Nilofar , Diaz Luis A. , Murphy Adrian , Lee Valerie , Fishman Elliot K. , Hruban Ralph H. , Liang Tingbo , Cameron John L. , Makary Martin , Weiss Matthew J. , Ahuja Nita , He Jin , Wolfgang Christopher L. , Huang Chiung‐Yu , Zheng Lei
Published: June 2017

The use of neoadjuvant chemotherapy or radiation for borderline resectable pancreatic adenocarcinoma (BL‐PDAC) is increasing. However, the impact of neoadjuvant chemotherapy and radiation therapy on the outcome of BL‐PDAC remains to be elucidated. We performed a retrospective analysis of 93 consecutive patients who were diagnosed with BL‐PDAC and primarily followed at Johns Hopkins Hospital between February 2007 and December 2012. Among 93 patients, 62% received upfront neoadjuvant chemotherapy followed by chemoradiation, whereas 20% received neoadjuvant chemoradiation alone and 15% neoadjuvant chemotherapy alone. Resectability following all neoadjuvant therapy was 44%. Patients who underwent resection with a curative intent had a median overall survival (mOS) of 25.8 months, whereas those who did not undergo surgery had a mOS of 11.9 months. However, resectability and overall survival were not significantly different between the three types of neoadjuvant therapy. Nevertheless, 22% (95% CI, 0.13–0.36) of the 58 patients who received upfront chemotherapy followed by chemoradiation remained alive for a minimum of 48 months compared to none of the 19 patients who received upfront chemoradiation. Among patients who underwent curative surgical resection, 32% (95% CI, 0.19–0.55) of those who received upfront chemotherapy remained disease free at least 48 months following surgical resection, whereas none of the eight patients who received upfront chemoradiation remained disease free beyond 24 months following surgical resection. Neoadjuvant therapy with upfront chemotherapy may result in long‐term survival in a subpopulation of patients with BL‐PDAC.
Impact of postoperative complications on the colorectal cancer survival and recurrence: analyses of pooled individual patients’ data from three large phase III randomized trials
Authors: Aoyama Toru , Oba Koji , Honda Michitaka , Sadahiro Sotaro , Hamada Chikuma , Mayanagi Shuhei , Kanda Mitsuro , Maeda Hiromichi , Kashiwabara Kosuke , Sakamoto Junichi , Saji Shigetoyo , Yoshikawa Takaki
Published: June 2017

This study assessed the impact of postoperative complications on the colorectal cancer survival and recurrence after curative surgery using pooled individual patients’ data from three large phase III randomized trials. In total, 5530 patients were included in this study. The patients were classified as those with postoperative complications (C group) and those without postoperative complications (NC group). The risk factors for the overall survival (OS) and the disease‐free survival (DFS) were analyzed. Postoperative complications were found in 861 (15.6%) of the 5530 patients. The OS and DFS rates at 5 years after surgery were 68.9% and 74.8%, respectively, in the C group and 75.8% and 82.2%, respectively, in the NC group, values that were significantly different between the two groups (P < 0.001). The multivariate analysis demonstrated that postoperative complications were a significant independent risk factor for the OS and DFS. Postoperative complications can worsen the colorectal cancer survival and risk of recurrence. Surgical morbidity must be considered as a stratification factor in future phase III trials evaluating the effects of adjuvant chemotherapy on colorectal cancer.
The impact of comorbidity on mortality in multiple myeloma: a Danish nationwide population‐based study
Authors: Gregersen Henrik , Vangsted Annette Juul , Abildgaard Niels , Andersen Niels Frost , Pedersen Robert Schou , Frølund Ulf Christian , Helleberg Carsten , Broch Bettina , Pedersen Per Trøllund , Gimsing Peter , Klausen Tobias Wirenfeldt
Published: June 2017

To describe the prevalence of comorbidity and its impact on survival in newly diagnosed multiple myeloma patients compared with population controls. Cases of newly diagnosed symptomatic multiple myeloma during the 2005–2012 period were identified in the Danish National Multiple Myeloma Registry. For each myeloma patient, 10 members of the general population matched by age and sex were chosen from the national Civil Registration System. Data on comorbidity in the myeloma patients and the general population comparison cohort were collected by linkage to the Danish National Patient Registry (DNPR). Cox proportional hazards regression models were used to evaluate the prognostic significance of comorbidity. The study included 2190 cases of multiple myeloma and 21,900 population controls. The comorbidity was increased in multiple myeloma patients compared with population controls, odds ratio (OR) 1.4 (1.1–1.7). The registration of comorbidity was highly increased within the year preceding diagnosis of multiple myeloma (OR 3.0 [2.5–3.5]), which was attributable to an increased registration of various diseases, in particular, renal disease with OR 11.0 (8.1–14.9). The median follow‐up time from diagnosis of multiple myeloma for patients alive was 4.3 years (interquartile range 2.4–6.3). Patients with registered comorbidity had increased mortality compared with patients without comorbidity, hazard ratio 1.6 (1.5–1.8). Multiple myeloma patients have increased comorbidity compared with the background population, in particular during the year preceding the diagnosis of myeloma.
Acute changes in histopathology and intravascular imaging after catheter‐based renal denervation in a porcine model
Authors: Sakaoka Atsushi , Takami Akiyuki , Onimura Yuji , Hagiwara Hitomi , Terao Hisako , Kumagai Fumiaki , Matsumura Kiyoshi
Published: June 2017

Objectives

We first aimed to identify the histopathological changes occurring immediately after renal denervation (RDN) with radiofrequency energy, and then to assess the feasibility of determining procedural success using currently available clinical intravascular imaging techniques.

Background

Catheter‐based RDN has been used as an alternative therapy for hypertension. However, no practical endpoint to determine procedural success during treatment has been established.

Methods

A total of 39 ablation lesions were induced in vivo in eight porcine renal arteries and a total of 15 ablation lesions were induced ex vivo in five excised porcine renal arteries with a radiofrequency delivery device. Acute histological changes and appearance on intravascular imaging of the lesions were investigated with light microscopy, transmission electron microscopy, intravascular ultrasound (IVUS), and optical frequency domain imaging (OFDI).

Results

Marked changes were noted in media, adventitia, and perirenal‐arterial nerves immediately after in vivo ablation. Changes visualized on IVUS were characterized by focal adventitial thickening comprising a relatively echogenic layer around a heterogeneously hypoechoic interior region, and on OFDI as disappearance of the external elastic membrane signals with high scattering of signals in the surface layer. The changes after ex vivo ablation were histopathologically identical to those from in vivo ablation. There were statistically significant positive correlations in measured dimensions (area, depth, width, and diameter) of ablation lesions between histopathology and IVUS/OFDI findings (Pearson correlation coefficients = 0.69–0.77).

Conclusions

These findings suggest that observation of treated renal arteries by IVUS or OFDI immediately after RDN improves the success rate of RDN.
Carfilzomib and dexamethasone for extramedullary myeloma with pleuropericardial involvement
Authors: Español Ignacio , Romera Marta , Gutiérrez‐Meca María Dolores , García Maria del Carmen , Tejedor Aurelia , Martínez Antonio , Ibáñez Jerónima , De Arriba Felipe , Minguela Alfredo , Iturbe Teodoro , López Maria Dolores
Published: June 2017

Key Clinical Message

The dismal outcome of pleuropericardial extramedullary multiple myeloma (EMM) reflects both the selection of resistant disease and absence of useful drugs. Carfilzomib and dexamethasone should be explored in advanced EMM patients, even for bortezomib‐resistant patients, as may provide much longer overall survival than previously reported treatments.
Urticaria vasculitis in a child: a case report and literature review
Authors: Imbernón‐Moya Adrián , Vargas‐Laguna Elena , Burgos Fernando , Fernández‐Cogolludo Eva , Aguilar‐Martínez Antonio , Gallego‐Valdés Miguel Ángel
Published: June 2017

Key Clinical Message

Annular urticarial lesions in a child must establish a main differential diagnosis with urticaria multiforme, common urticaria, acute hemorrhagic edema of infancy, erythema marginatum, erythema annulare centrifugum, annular erythema in childhood, erythema multiforme, Sweet's syndrome, Schönlein‐Henoch purpura, erythematosus lupus, several systemic vasculitis, and serum sickness.
Auto‐Reduction Behavior of Cobalt on Graphitic Carbon Nitride Coated Alumina Supports for Fischer–Tropsch Synthesis
Authors: Park Hunmin , Kim Kwang Young , Youn Duck Hyun , Choi Yo Han , Kim Won Young , Lee Jae Sung
Published: June 2017

Graphitic carbon nitride (g‐C3N4)‐coated alumina (CN‐Al) is investigated as a support material for a cobalt‐based Fischer–Tropsch synthesis (FTS) catalyst. The g‐C3N4 blocks the interaction between cobalt and alumina to hinder the formation of irreducible cobalt oxide species, and improves the dispersion of metallic cobalt species on the CN‐Al support. Furthermore, the coated g‐C3N4 is decomposed during the pre‐annealing process even under inert conditions to evolve reductive carbon monoxide gas that directly reduces the cobalt oxide species to metallic cobalt. Hence, the catalyst can be activated without typical hydrogen pretreatment. Moreover, reduction promotion by expensive noble metals such as Pt is not needed either. Because of the improved dispersion and reducibility of the cobalt species on the CN‐Al support, the catalytic FTS activity of Co/CN‐Al is higher compared with the conventional Co/Al2O3 catalyst.
Electrocatalytic Properties of Cuprous Delafossite Oxides for the Alkaline Oxygen Reduction Reaction
Authors: Draskovic Thomas I. , Wu Yiying
Published: June 2017

Inspired by the oxygen‐binding copper sites in biomolecules, a series of cuprous delafossite oxides (CuBO2; B=Sc, Y, La) with similar interatomic copper distances were utilized as electrocatalysts for the oxygen reduction reaction (ORR). The carbon‐supported oxides showed improved onset potential, current, and electron‐transfer number over carbon black, with CuLaO2 having the highest prevalence of the complete four‐electron reduction. The oxygen electrocatalytic activity of the copper site in delafossite oxides was demonstrated.
Thermal Conductivity Measurement of Bulk Solids
Authors: Hlosta Jakub , Zurovec David , Gelnar Daniel , Zegzulka Jiri , Necas Jan
Published: June 2017

The coefficient of thermal conductivity of particulates and powders is of great importance in process engineering. The prediction of thermal properties of powders using empirical equations is still difficult due to the wide range of specific attributes. This article describes a new measurement methodology for a laboratory device that can be used to determine the thermal conductivity of bulk solids. The presented results show that the created device is highly applicable in industrial practice. It is possible to examine the coefficient of thermal conductivity depending on the sample temperature, the granulometry results and the morphological composition, the moisture content, the degree of consolidation, and other variables that may enter into the entire process and affect it significantly.
Catalytic Enantioselective Michael Addition Reactions of Tertiary Enolates Generated by Detrifluoroacetylation
Authors: Zhu Yi , Zhang Wenzhong , Mei Haibo , Han Jianlin , Soloshonok Vadim A. , Pan Yi
Published: June 2017

This work describes, for the first time, Michael addition reactions of tertiary fluoro‐enolates in situ generated by detrifluoroacetylation with 1‐(1‐(phenylsulfonyl) vinylsulfonyl)benzene. Excellent enantioselectivity and chemical yields were achieved with application of catalysts (10 mol %) derived from Cu(OTf)2 and (1S,2S)‐1,2‐diphenylethane‐1,2‐diamine. These reactions show a considerable degree of structural generality and allow the preparation of new types of biologically relevant molecules that contain quaternary C−F stereogenic carbon atoms and feature five‐, six‐, or seven‐membered rings as well as heterocyclic 3‐fluoro‐2,3‐dihydrochromen‐4‐one moieties.
Triplet Harvesting with a Simple Aromatic Carbonyl
Authors: Torres Ziegenbein Christian , Fröbel Sascha , Glöß Maria , Nobuyasu Roberto S. , Data Przemyslaw , Monkman Andrew , Gilch Peter
Published: June 2017

The efficiency of organic light‐emitting diodes crucially depends on triplet harvesters. These accept energy from triplet correlated electron hole pairs and convert it into light. Here, experimental evidence is given that simple aromatic carbonyls, such as thioxanthone, could serve this purpose. In these compounds, the emissive 1ππ* excitation may rapidly equilibrate with an upper triplet state (3nπ*). This equilibrium may persist for nanoseconds. Population of the 3nπ* state via energy transfer from an electron hole pair should result in fluorescence emission and thereby triplet harvesting. To demonstrate the effect, solutions of 1,4‐dichlorobenzene (triplet sensitizer) and thioxanthone (harvester) were excited at 266 nm with a nanosecond laser. The emission decay reveals a 100 ns decay absent in the thioxanthone only sample. This matches predictions for an energy transfer limited by diffusion and gives clear evidence that thioxanthone can convert triplet excitations into light.
Multilayer N‐doped Graphene Films as Photoelectrodes for H2 Evolution
Authors: Garcia Alejandra , Albero Josep , García Hermenegildo
Published: June 2017

Multilayer N‐doped graphene photoelectrodes have been prepared following a straightforward one‐step pyrolytic fabrication method. The N‐doped graphene photoelectrodes have been demonstrated to work both as semitransparent electrodes and as efficient photoelectrocatalysts for H2 evolution at low bias. N‐doped graphene photoelectrodes exhibited a constant H2 generation rate of 3.64 μmol h−1 cm2 at 0.2 V under 3443 W m−2 irradiation for 17 h, reaching an applied‐bias‐compensated solar‐to‐hydrogen efficiency of 1.8 %. The N‐doped graphene photoelectrodes show light‐intensity dependence as well as photocatalytic activity for H2 evolution in the UV/Vis spectral region. Impedance spectroscopy provides experimental evidence indicating that charge separation within N‐doped graphene increases upon positive bias polarization of the photoelectrode.
Effect of Interplay Between Isotropic Gases on Microstructural Evolution of Single Crystal Diamond
Authors: Jain L. , Mohapatra D. R. , Basu R. , Misra D. S. , Misra Abha , Samajdar I.
Published: June 2017

Homo‐epitaxial (100) single crystal diamond films of different isotopic (13C) compositions were synthesized by micro‐wave plasma chemical vapor deposition. An increase in 13C concentration (0 to 99%) demonstrated clear developments in microstructures. These are related to changes in: (i) morphology, (ii) residual strain and dislocations and (iii) mesoscopic defects. (i) was mainly through increased presence of steps/ledges and corresponding increase in surface roughness. This was accompanied by significantly higher residual strain and presence/energy of dislocations. 13C concentration also determined mesoscopic defects: presence of non‐(100) orientations, nature of grain boundaries and micro‐segregations of 13C and/or CH.A link has been established between various reproducible, experimental observations through stipulated increase in interfacial energy and stresses present at grain boundaries.
Arthropod communities on hybrid and parental cottonwoods are phylogenetically structured by tree type: Implications for conservation of biodiversity in plant hybrid zones
Authors: Jarvis Karl J. , Allan Gerard J. , Craig Ashley J. , Beresic‐Perrins Rebecca K. , Wimp Gina , Gehring Catherine A. , Whitham Thomas G.
Published: June 2017

Although hybridization in plants has been recognized as an important pathway in plant speciation, it may also affect the ecology and evolution of associated communities. Cottonwood species (Populus angustifolia and P. fremontii) and their naturally occurring hybrids are known to support different plant, animal, and microbial communities, but no studies have examined community structure within the context of phylogenetic history. Using a community composed of 199 arthropod species, we tested for differences in arthropod phylogenetic patterns within and among hybrid and parental tree types in a common garden. Three major patterns emerged. (1) Phylogenetic diversity (PD) was significantly different between arthropod communities on hybrids and Fremont cottonwood when pooled by tree type. (2) Mean phylogenetic distance (MPD) and net relatedness index (NRI) indicated that communities on hybrid trees were significantly more phylogenetically overdispersed than communities on either parental tree type. (3) Community distance (Dpw) indicated that communities on hybrids were significantly different than parental species. Our results show that arthropod communities on parental and hybrid cottonwoods exhibit significantly different patterns of phylogenetic structure. This suggests that arthropod community assembly is driven, in part, by plant–arthropod interactions at the level of cottonwood tree type. We discuss potential hypotheses to explain the effect of plant genetic dissimilarity on arthropod phylogenetic community structure, including the role of competition and environmental filtering. Our findings suggest that cottonwood species and their hybrids function as evolutionarily significant units (ESUs) that affect the assembly and composition of associated arthropod communities and deserve high priority for conservation.
In situ Detection of Microplastics: Single Microparticle‐electrode Impacts
Authors: Shimizu Kenichi , Sokolov Stanislav V. , Kätelhön Enno , Holter Jennifer , Young Neil P. , Compton Richard G.
Published: June 2017

Particle‐impact electrochemistry is employed to study spherical polyethylene microparticles suspended in an aqueous solution. This electrochemical method detects polyethylene microparticles impacting on a carbon fiber electrode generating a transient current response or “spike”. We interpret the physio‐chemical origin of the spikes and accurately identify particle size distributions and concentrations for microparticles of sizes 1–10 μm.
Cell specificity of magnetic cell seeding approach to hydrogel colonization
Authors: Singh Raminder , Wieser Anna , Reakasame Supachai , Detsch Rainer , Dietel Barbara , Alexiou Christoph , Boccaccini Aldo R. , Cicha Iwona
Published: June 2017

Tissue‐engineered scaffolds require an effective colonization with cells. Superparamagnetic iron oxide nanoparticles (SPIONs) can enhance cell adhesion to matrices by magnetic cell seeding. We investigated the possibility of improving cell attachment and growth on different alginate‐based hydrogels using fibroblasts and endothelial cells (ECs) loaded with SPIONs. Hydrogels containing pure alginate (Alg), alginate dialdehyde crosslinked with gelatin (ADA‐G) and Alg blended with G or silk fibroin (SF) were prepared. Endothelial cells and fibroblasts loaded with SPIONs were seeded and grown on hydrogels for up to 7 days, in the presence of magnetic field during the first 24 h. Cell morphology (fluorescent staining) and metabolic activity (WST‐8 assay) of magnetically‐seeded versus conventionally seeded cells were compared. Magnetic seeding of ECs improved their initial attachment and further growth on Alg/G hydrogel surfaces. However, we did not achieve an efficient and stable colonization of ADA‐G films with ECs even with magnetic cell seeding. Fibroblast showed good initial colonization and growth on ADA‐G and on Alg/SF. This effect was further significantly enhanced by magnetic cell seeding. On pure Alg, initial attachment and spreading of magnetically‐seeded cells was dramatically improved compared to conventionally‐seeded cells, but the effect was transient and diminished gradually with the cessation of magnetic force. Our results demonstrate that magnetic seeding improves the strength and uniformity of initial cell attachment to hydrogel surface in cell‐specific manner, which may play a decisive role for the outcome in tissue engineering applications. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2948–2956, 2017.
Regulation of the fate of dental‐derived mesenchymal stem cells using engineered alginate‐GelMA hydrogels
Authors: Ansari Sahar , Sarrion Patricia , Hasani‐Sadrabadi Mohammad Mahdi , Aghaloo Tara , Wu Benjamin M , Moshaverinia Alireza
Published: June 2017

Mesenchymal stem cells (MSCs) derived from dental and orofacial tissues provide an alternative therapeutic option for craniofacial bone tissue regeneration. However, there is still a need to improve stem cell delivery vehicles to regulate the fate of the encapsulated MSCs for high quality tissue regeneration. Matrix elasticity plays a vital role in MSC fate determination. Here, we have prepared various hydrogel formulations based on alginate and gelatin methacryloyl (GelMA) and have encapsulated gingival mesenchymal stem cells (GMSCs) and human bone marrow MSCs (hBMMSCs) within these fabricated hydrogels. We demonstrate that addition of the GelMA to alginate hydrogel reduces the elasticity of the hydrogel mixture. While presence of GelMA in an alginate‐based scaffold significantly increased the viability of encapsulated MSCs, increasing the concentration of GelMA downregulated the osteogenic differentiation of encapsulated MSCs in vitro due to decrease in the stiffness of the hydrogel matrix. The osteogenic suppression was rescued by addition of a potent osteogenic growth factor such as rh‐BMP‐2. In contrast, MSCs encapsulated in alginate hydrogel without GelMA were successfully osteo‐differentiated without the aid of additional growth factors, as confirmed by expression of osteogenic markers (Runx2 and OCN), as well as positive staining using Xylenol orange. Interestingly, after two weeks of osteo‐differentiation, hBMMSCs and GMSCs encapsulated in alginate/GelMA hydrogels still expressed CD146, an MSC surface marker, while MSCs encapsulated in alginate hydrogel failed to express any positive staining. Altogether, our findings suggest that it is possible to control the fate of encapsulated MSCs within hydrogels by tuning the mechanical properties of the matrix. We also reconfirmed the important role of the presence of inductive signals in guiding MSC differentiation. These findings may enable the design of new multifunctional scaffolds for spatial and temporal control over the fate and function of stem cells even post‐transplantation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2957–2967, 2017.
Titanium‐released from dental implant enhances pre‐osteoblast adhesion by ROS modulating crucial intracellular pathways
Authors: Rossi M. C. , Bezerra F. J. B. , Silva R. A. , Crulhas B. P. , Fernandes C. J. C. , Nascimento A. S. , Pedrosa V. A. , Padilha P. , Zambuzzi W. F.
Published: June 2017

It is important to understand the cellular and molecular events that occur at the cell–material interface of implants used for bone repair. The mechanisms involved in the initial stages of osteoblast interactions with the surface of the implant material must be decisive for cell fating surrounding them. In order to address this issue, we decided to investigate if conditioned medium for dental implants was able to modulate murine pre‐osteoblast metabolism. First, we determined the concentration of titanium (Ti)‐containing conditioned medium and found that it was 2‐fold increased (p < 0.0001). We have reported that this conditioned medium significantly up‐modulated pre‐osteoblast adhesion up to 24 h (p < 0.0001). In parallel, our results showed that both phosphorylations of FAK (focal adhesion kinase) at Y397 (p < 0.0011) and Cofilin at Ser03 (p < 0.0053) were also up‐modulated, as well as for Rac1 expression (p < 0.0175); both of them are involved with cell adaptation by rearranging cytoskeleton actin filaments. Thereafter, Ti‐containing medium stimulated ROS (reactive oxygen species) production by pre‐osteoblast cells, and it is very possible that ROS compromised PTP‐1B (protein tyrosine phosphatase 1B) activation since PTP1B was down‐phosphorylated (p < 0.0148). The low PTP activity guarantees the phosphorylation of FAK at Y‐residue, causing better pre‐osteoblast adhesion in response to Ti‐containing medium. Altogether, these data indicate that ROS indirectly modulate FAK phosphorylation in response to Ti‐released from dental implants. Taken the results in account, these data showed for the first time that the implanted dental device is able to dynamically affect surrounding tissues, mainly by promoting a better performance of the pre‐osteoblast cells. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2968–2976, 2017.
Nonimmediate allergic reactions induced by Mesna
Authors: Shimogori Kei , Araki Makoto , Shibazaki Shunichi , Tuda Katuji , Miura Kohei
Published: June 2017

Mesna (2‐mercaptoethane sulfonate Na), a drug that alleviates cyclophosphamide (CYC)‐induced hemorrhagic cystitis, is frequently used to treat cancer and collagen diseases. A 33‐year‐old woman presented with high fever during CYC‐based induction therapy for systemic lupus erythematosus. Her final diagnosis was mesna‐induced drug hypersensitivity. Although mesna is widely used, allergic reactions are rare. This may be because of misdiagnosis as a primary disease flare‐up, infection, or CYC‐induced hypersensitivity reaction, which are commonly reported. Thus, accurate diagnosis is important for completion of the CYC‐based regimen.
Two‐step irradiance schedule versus single‐dose cold compress for pain control during 5‐aminolevulinic acid‐based photodynamic therapy of condyloma acuminatum
Authors: Shao Xiaonan , Wang Fang , Xu Bin
Published: June 2017

Objective

The purpose of this study was to investigate the effect of two‐step irradiance schedule in relieving pain during PDT of CA.

Methods

The study was a prospective, controlled trial of 141 CA patients who were randomly divided into Group A (two‐step irradiance schedule) and Group B (single‐dose cold compress). The numeric rating scales (NRS) of patients’ pain were recorded at 5, 10, 15, and 20 minutes during each PDT.

Results

The efficacy of PDT and NRS scores of patients in the two groups were compared. There was no significant difference in gender, age, lesion site, and disease course between the two groups (P > 0.05). In addition, the cure rate of patients in the two groups was not significantly different (97.1% vs. 95.8%, χ2 = 0.000, P = 1.000). However, the NRS scores at different time points and number of PDT sessions were significantly different (F = 198.233 and 165.224, respectively, P < 0.05). The NRS scores of patients in Group A were significantly lower than those of patients in Group B (F = 82.762, P < 0.0001). Moreover, the NRS scores at different positions were significantly different (F = 28.286, P < 0.0001). The NRS scores of penis were significantly lower than those of the vulva and crissum (P < 0.05).

Conclusions

Compared with single‐dose cold compress, two‐step irradiance schedule could more significantly reduce the patients’ pain degree during treatment, especially for vulva and crissum. Lasers Surg. Med. 49:908–912, 2017. © 2017 Wiley Periodicals, Inc.
Prospective validation of pathologic complete response models in rectal cancer: Transferability and reproducibility
Authors: van Soest Johan , Meldolesi Elisa , van Stiphout Ruud , Gatta Roberto , Damiani Andrea , Valentini Vincenzo , Lambin Philippe , Dekker Andre
Published: June 2017

Purpose

Multiple models have been developed to predict pathologic complete response (pCR) in locally advanced rectal cancer patients. Unfortunately, validation of these models normally omit the implications of cohort differences on prediction model performance. In this work, we will perform a prospective validation of three pCR models, including information whether this validation will target transferability or reproducibility (cohort differences) of the given models.

Methods

We applied a novel methodology, the cohort differences model, to predict whether a patient belongs to the training or to the validation cohort. If the cohort differences model performs well, it would suggest a large difference in cohort characteristics meaning we would validate the transferability of the model rather than reproducibility. We tested our method in a prospective validation of three existing models for pCR prediction in 154 patients.

Results

Our results showed a large difference between training and validation cohort for one of the three tested models [Area under the Receiver Operating Curve (AUC) cohort differences model: 0.85], signaling the validation leans towards transferability. Two out of three models had a lower AUC for validation (0.66 and 0.58), one model showed a higher AUC in the validation cohort (0.70).

Discussion

We have successfully applied a new methodology in the validation of three prediction models, which allows us to indicate if a validation targeted transferability (large differences between training/validation cohort) or reproducibility (small cohort differences).