bluuebunny/crossref_metadata_2025 huggingface dataset:
Interference of Seasonal Variation on the Antimicrobial and Cytotoxic Activities of the Essential Oils from the Leaves of Iryanthera polyneura in the Amazon Rain Forest
Authors: Martins Erika R. , Díaz Ingrit E. C. , Paciencia Mateus L. B. , Fana Sergio A. , Morais Damila , Eberlin Marcos N. , Silva Jefferson S. , Silveira Elielson R. , Barros Matheus P. , Suffredini Ivana B.
Published: August 2019

The essential oils (EOs) obtained from the leaves of Iryanthera polyneura Ducke trees was chemically Assessed and tested for the ability of inhibiting the growth of Candida albicans, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus mutans and S. sanguinis. The oil was also tested against breast (MCF‐7) and prostate (PC‐3) cancer cell lines. Minimum bactericidal concentrations (MBCs) and 50 % inhibition concentrations (IC50) values were obtained. EOs were active against Gram‐positive bacteria. Spathulenol, α‐cadinol and τ‐muurolol were major components of EOs. The oils showed a higher cytotoxicity against PC‐3 than MCF‐7 cells, although the oils were active against both cell types. Oils obtained from leaves collected in the dry season were more active against E. faecalis, S. aureus and PC‐3, while the oils obtained from leaves collected in the rainy season were more active against S. mutans, S. sanguinis and MCF‐7. The antibacterial and cytotoxic activities of the essential oils from the leaves of I. polyneura are related to the seasonal climate variation and are influenced by compounds that are minor components of the oils.
Successful cryoballoon ablation of a focal atrial tachycardia in a patient with situs inversus and dextrocardia
Authors: Akkaya Ersan , Sözener Korkut , Rixe Johannes , Erkapic Damir
Published: August 2019

Cryoballoon ablation of an arrhythmogenic focus alongside a pulmonary vein as an alternative to radiofrequency ablation may be feasible and safe in patients with situs inversus and dextrocardia.
A practical convolutional neural network model for discriminating Raman spectra of human and animal blood
Authors: Dong Jialin , Hong Mingjian , Xu Yi , Zheng Xiangquan
Published: August 2019

A practical convolutional neural network (CNN) model is proposed to discriminate the Raman spectra of human and animal blood. The proposed network, which discards the pooling layers to avoid loss of data, consists of preprocessing and fully connected classifier layers. Two preprocessing layers, namely, denoising and baseline correction layer, are designed to allow only one kernel for each layer to explicitly suppress the noise and subtract varying background of the spectra. The network combines the preprocessing and discrimination to form a whole processing unit and learns parameters adaptively by training from 217 of 326 Raman spectra of human, dog, and rabbit blood samples. The trained network is evaluated by remaining 109 samples and shows better classification accuracy, as compared with the PLSDA and SVM.
A Selective Cucurbit[8]uril‐Peptide Beacon Ensemble for the Ratiometric Fluorescence Detection of Peptides
Authors: Maity Debabrata , Assaf Khaleel I. , Sicking Wilhelm , Hirschhäuser Christoph , Nau Werner M. , Schmuck Carsten
Published: August 2019

A convenient supramolecular strategy for constructing a ratiometric fluorescent chemosensing ensemble, consisting of a macrocyclic host (cucurbit[8]uril CB[8]), and a pyrene‐tagged amphiphilic peptide beacon (AP 1), is reported. AP 1 unfolds upon encapsulation of the pyrene termini into the hydrophobic CB[8] cavity. This changes pyrene excimer to monomer emission. Substrates with higher affinity for the CB[8] cavity can displace AP 1 from the ensemble. The released AP 1 folds again to form a pyrene excimer, which allows for the ratiometric fluorescence monitoring of the substrate. In this report, the ensemble capacity for ratiometric fluorescence monitoring of biological substrates, such as amino acid derivatives, specific peptides, and proteins, in aqueous media is demonstrated.
SiO2‐Coated ZnO Nanoflakes Decorated with Ag Nanoparticles for Photocatalytic Water Oxidation
Authors: Bettini Simona , Pagano Rosanna , Semeraro Paola , Ottolini Michela , Salvatore Luca , Marzo Fabio , Lovergine Nicola , Giancane Gabriele , Valli Ludovico
Published: August 2019

Many strategies have been adopted to improve the photoinduced features of zinc oxide nanostructures for different application fields. In this work, zinc oxide has been synthesised and decorated by plasmonic metal nanoparticles to enhance its photocatalytic activity in the visible range. Furthermore, an insulating layer of SiO2 has been grown between the surface of zinc oxide nanoflakes and silver nanoparticles. A synthetic procedure that allows the accurate modulation of the insulating layer thickness in the range 5–40 nm has been developed. Evidences highlight the crucial role of the SiO2 layer in dramatically increasing photocatalytic water oxidation promoted by the nanostructure under both UV and visible illumination. An ideal thickness value of about 10 nm has been demonstrated to guarantee the plasmon‐induced resonance energy‐transfer process and to quench the Förster resonance energy‐transfer mechanism; thus, optimising the local surface plasmon resonance effect and water oxidation properties.
Synthesis and Cyclization‐Induced Charge Transfer of Rectangular Bisterthiophenesiloxanes
Authors: Li Chensen , Hu Jian , Tashiro Kohji , Ren Zhongjie , Yan Shouke
Published: August 2019

Cyclization‐modified terthiophene displays the change of emission behavior from locally excited (LE) to the intramolecular charge transfer (ICT) state. The rectangular bisterthiophenesiloxanes (DSiTh) was successfully prepared by π–π‐stacking‐aided hydrogen‐bonding interactions. Cyclization‐induced ICT in DSiTh could be observed, which was confirmed by absorption spectra, fluorescence spectra, and quantum chemistry analysis. The cyclization produces a strong intramolecular electron redistribution of a highly packed π‐conjugated terthiophene. Thus, a distinctive variation of the dipole moment and a through‐space ICT happen.
Efficacy of increased dose of rupatadine up to 20 mg on itching in Japanese patients due to chronic spontaneous urticaria, dermatitis, or pruritus: A post hoc analysis of phase III clinical trial
Authors: Hide Michihiro , Suzuki Takamasa , Tanaka Ayaka , Aoki Hiroshi
Published: August 2019

Objectives

The effect of rupatadine, a novel H1 antihistamine with platelet‐activating factor antagonist activity, had been demonstrated for itching in Japanese patients with chronic spontaneous urticaria, dermatitis, or pruritus in a 12‐month, open‐label clinical trial (JapicCTI‐152787). However, patients could have received an updose at various timings due to distinct reasons in the study; timing of updose was not evaluated. This study aimed to elucidate the relationship between performance of rupatadine and timing of updose.

Methods

For 206 enrolled patients was evaluated the total pruritus score (TPS) to Week 2 with 10 mg rupatadine. From Week 3 to Week 52, rupatadine was updosed to 20 mg accordingly. Subpopulation was categorized by absence/presence of updosing and timing of updose (Week 3 or ≥Week 5).

Results

Reduction of TPS from baseline to Week 2 in patients updosed at Week 3 was significantly lower than those given an updose at ≥Week 5 and fixed dose. However, significant improvement in the change in mean TPS from 1 week pre‐updose to the second week post‐updose was achieved regardless of updose timing, scoring −0.903 for Week 3 and −0.983 for ≥Week 5 (P < 0.001).

Conclusions

The results inferred the inclusivity of patients who either updosed during the earlier phase due to lack of efficacy, or later due to aggravation of symptoms. The results of this subgroup analysis produced evidence of appropriateness for using 10 mg rupatadine as the starting dose, and evaluating the necessity of updose to 20 mg during the first 2 weeks for nonresponsive patients.
Risikobewertung von Lebensmittel‐Kontaminanten
Authors: Schrenk Dieter
Published: August 2019

Chemische Kontaminanten in Lebensmitteln sind Stoffe, die unbeabsichtigt in das Lebensmittel gelangt sind und es belasten. Hierzu zählen zum Beispiel Dioxine, Schwermetalle oder Mykotoxine. Als solche stehen sie häufig im Fokus des Interesses von Journalisten und Verbrauchern. Ihre Aufdeckung wird oft irrtümlich als Indikator für eine ungenügende Sicherheit unserer Lebensmittel betrachtet. Im Gegensatz dazu beweist ihre Identifizierung, auf welch weltweit hohem Niveau die Lebensmittelsicherheit in Deutschland und Europa steht.

Ein wichtiges Element des Verbraucherschutzes gegenüber Lebensmittel‐Kontaminanten ist die wissenschaftliche Risikobewertung, das ‚risk assessment‘. Es beruht auf einer möglichst genauen Kenntnis der Gehalte der Kontaminante in verschiedenen Produkten, der Verzehrsmengen belasteter Lebensmittel, der toxikologischen Eigenschaften des Stoffes insbesondere seiner Wirkmechanismen und der quantitativen Dosis‐Wirkungs‐Beziehungen. Von ausschlaggebender Bedeutung für die Wahl der anzuwenden Methode des risk assessment ist dabei die Frage, ob die Substanz als gentoxisches Kanzerogen wirkt oder nicht. Vorschläge für Grenzwerte oder Analysen der existierenden Sicherheitsmargen sollen den Entscheidungsträgern in Politik und Behörden als Grundlage für regulatorische Maßnahmen dienen.
Sliding filament and fixed filament mechanisms contribute to ring tension in the cytokinetic contractile ring
Authors: Alonso‐Matilla Roberto , Thiyagarajan Sathish , O'Shaughnessy Ben
Published: August 2019

A fundamental challenge in cell biology is to understand how cells generate actomyosin‐based contractile force. Here we study the actomyosin contractile ring that divides cells during cytokinesis and generates tension by a mechanism that remains poorly understood. Long ago a muscle‐like sliding filament mechanism was proposed, but evidence for sarcomeric organization in contractile rings is lacking. We develop a coarse‐grained model of the fission yeast cytokinetic ring, incorporating the two myosin‐II isoforms Myo2 and Myp2 and severely constrained by experimental data. The model predicts that ring tension is indeed generated by a sliding filament mechanism, but a spatially and temporally homogeneous version of that in muscle. In this mechanism all pairs of oppositely oriented actin filaments are rendered tense as they are pulled toward one another and slide through clusters of myosin‐II. The mechanism relies on anchoring of actin filament barbed ends to the plasma membrane, which resists lateral motion and enables filaments to become tense when pulled by myosin‐II. A second fixed filament component is independent of lateral anchoring, generated by chains of like‐oriented actin filaments. Myo2 contributes to both components, while Myp2 contributes to the sliding filament component only. In the face of instabilities inherent to actomyosin contractility, organizational homeostasis is maintained by rapid turnover of Myo2 and Myp2, and by drag forces that resist lateral motion of actin, Myo2 and Myp2. Thus, sliding and fixed filament mechanisms contribute to tension in the disordered contractile ring without the need for the sarcomeric architecture of muscle.
CUDA offloading for energy‐efficient and high‐frame‐rate simulations using tablets
Authors: Martinez‐Noriega Edgar Josafat , Yazaki Syunji , Narumi Tetsu
Published: August 2019

The multiple sensors and touch capabilities of mobile devices are defining new methods of computer interaction. However, the computing power of such devices is not currently sufficient for new applications that require compute‐intensive applications. Using graphics processing units (GPUs) for general‐purpose computing with GPU programming models such as Compute Unified Device Architecture (CUDA) has been proved to accelerate simulations in supercomputers. Although, CUDA‐capable chips such as the Tegra K1 have been released on tablets can accelerate computer simulations, their absolute computing power and performance per watt are not comparable with ordinary GPUs. In this paper, we analyze a heterogeneous system composed of both of a tablet (client) and notebook with a low‐power GPU (server). Intensive computations on a tablet device are offloaded to a notebook GPU using the rCUDA middleware. Molecular dynamics (MD) simulations are performed using our test system, and the computing speed and performance per watt are reported. Implementing dynamic parallelism (DP) reduced the latency, doubling the total frames per second in some cases. Our system achieves better computational performance, and higher performance per watt than a tablet powered by a CUDA‐capable GPU. We achieved 21.7 Gflops/W by combining multiple client tablets and server, compared with 21.3 Gflops/W from the server itself.
Unveiling the Photo‐ and Thermal‐Stability of Cesium Lead Halide Perovskite Nanocrystals
Authors: Boote Brett W. , Andaraarachchi Himashi P. , Rosales Bryan A. , Blome‐Fernández Rafael , Zhu Feng , Reichert Malinda D. , Santra Kalyan , Li Jingzhe , Petrich Jacob W. , Vela Javier , Smith Emily A.
Published: August 2019

Lead halide perovskites possess unique characteristics that are well‐suited for optoelectronic and energy capture devices, however, concerns about their long‐term stability remain. Limited stability is often linked to the methylammonium cation, and all‐inorganic CsPbX3 (X=Cl, Br, I) perovskite nanocrystals have been reported with improved stability. In this work, the photostability and thermal stability properties of CsPbX3 (X=Cl, Br, I) nanocrystals were investigated by means of electron microscopy, X‐ray diffraction, thermogravimetric analysis coupled with FTIR (TGA‐FTIR), ensemble and single particle spectral characterization. CsPbBr3 was found to be stable under 1‐sun illumination for 16 h in ambient conditions, although single crystal luminescence analysis after illumination using a solar simulator indicates that the luminescence states are changing over time. CsPbBr3 was also stable to heating to 250 °C. Large CsPbI3 crystals (34±5 nm) were shown to be the least stable composition under the same conditions as both XRD reflections and Raman bands diminish under irradiation; and with heating the γ (black) phase reverts to the non‐luminescent δ phase. Smaller CsPbI3 nanocrystals (14±2 nm) purified by a different washing strategy exhibited improved photostability with no evidence of crystal growth but were still thermally unstable. Both CsPbCl3 and CsPbBr3 show crystal growth under irradiation or heat, likely with a preferential orientation based on XRD patterns. TGA‐FTIR revealed nanocrystal mass loss was only from liberation and subsequent degradation of surface ligands. Encapsulation or other protective strategies should be employed for long‐term stability of these materials under conditions of high irradiance or temperature.
In‐Situ Infrared Spectroscopy Applied to the Study of the Electrocatalytic Reduction of CO2: Theory, Practice and Challenges
Authors: Kas Recep , Ayemoba Onagie , Firet Nienke J. , Middelkoop Joost , Smith Wilson A. , Cuesta Angel
Published: August 2019

The field of electrochemical CO2 conversion is undergoing significant growth in terms of the number of publications and worldwide research groups involved. Despite improvements of the catalytic performance, the complex reaction mechanisms and solution chemistry of CO2 have resulted in a considerable amount of discrepancies between theoretical and experimental studies. A clear identification of the reaction mechanism and the catalytic sites are of key importance in order to allow for a qualitative breakthrough and, from an experimental perspective, calls for the use of in‐situ or operando spectroscopic techniques. In‐situ infrared spectroscopy can provide information on the nature of intermediate species and products in real time and, in some cases, with relatively high time resolution. In this contribution, we review key theoretical aspects of infrared reflection spectroscopy, followed by considerations of practical implementation. Finally, recent applications to the electrocatalytic reduction of CO2 are reviewed, including challenges associated with the detection of reaction intermediates.
1H NMR Chemosensing of Potassium Ions Enabled by Guest‐Induced Selectivity Switch of a Gold Nanoparticle/Crown Ether Nanoreceptor
Authors: Sun Xiaohuan , Rosa‐Gastaldo Daniele , De Biasi Federico , Rastrelli Federico , Mancin Fabrizio
Published: August 2019

Invited for this month's cover is the group of Prof. Fabrizio Mancin from the University of Padova, Italy. The cover picture shows an 18‐crown‐6‐functionalized gold nanoparticle that switches its molecular recognition preference from organic cations to organic anions in the presence of potassium ions, thus allowing 1H NMR sensing of potassium. Read the full text of the article at 10.1002/cplu.201900028.
Differential Effects of Ticagrelor With or Without Aspirin on Platelet Reactivity and Coagulation Activation: A Randomized Trial in Healthy Volunteers
Authors: Traby Ludwig , Kollars Marietta , Kaider Alexandra , Siller‐Matula Jolanta M. , Wolkersdorfer Martin F. , Wolzt Michael , Kyrle Paul A. , Eichinger Sabine
Published: August 2019

Dual antiplatelet therapy (DAPT) is standard in acute coronary heart disease but confers a bleeding risk. To compare the effects of ticagrelor‐monotherapy with ticagrelor‐based DAPT on hemostatic system activation, we conducted a randomized controlled trial in 44 volunteers using a loading‐dose regimen and measured platelet‐aggregometry triggered by adenosine diphosphate (multiple electrode aggregometry (MEA)‐ADP) and arachidonic acid (MEA‐AA), the vasodilator‐stimulated phosphoprotein (VASP), prothrombin fragment 1.2 (f1.2), and d‐Dimer. Ticagrelor‐based DAPT and ticagrelor‐monotherapy significantly decreased MEA‐ADP (Δmean: −51.4 (−56.9; −45.8) and −46.2 (−51.7; −40.7)) and VASP (Δmean: −70.3 (−76.2; −64.4) and −69.6 (−75.5; −63.7)) at 2 hours and over 24 hours. MEA‐AA was reduced significantly by both treatments (Δmean: −72.9 (−80.6; −65.3) and −25.7 (−33.3; −18.0)) at 2 hours, and stronger by ticagrelor‐based DAPT over 24 hours. Both treatments decreased f1.2 (geometric mean ratio (GMR): 0.92 (0.84; 1.01) and 0.88 (0.80; 0.96)) and d‐Dimer (GMR: 0.89 (0.86; 0.92) and 0.91 (0.88; 0.94)) at 2 hours and d‐Dimer over 24 hours. Ticagrelor‐monotherapy and ticagrelor‐based DAPT comparably affect hemostatic system activation.
Vertical Bridgman Growth of 42°RY‐Oriented LiTaO3 Single Crystal
Authors: Nishimura Eiichiro , Okano Katsuhiko , Terashima Akira , Hoshikawa Keigo
Published: August 2019

Crack‐free single crystals of 42°RY‐oriented lithium tantalate, 42°RY‐LiTaO3 (42°RY‐LT), are grown by the vertical Bridgman (VB) technique, using pure platinum bottomless crucibles to avoid cracking the seed crystal. The fundamental technical issues for 42°RY‐LT growth by the VB technique are clarified.
Analytical characterization of cache replacement policy impact on content delivery time in information‐centric networks
Authors: Seyyed Hashemi Seyyed Naser , Bohlooli Ali
Published: August 2019

Information‐centric networking (ICN) has emerged as a promising candidate for designing content‐based future Internet paradigms. ICN increases the utilization of a network through location‐independent content naming and in‐network content caching. In routers, cache replacement policy determines which content to be replaced in the case of cache free space shortage. Thus, it has a direct influence on user experience, especially content delivery time. Meanwhile, content can be provided from different locations simultaneously because of the multi‐source property of the content in ICN. To the best of our knowledge, no work has yet studied the impact of cache replacement policy on the content delivery time considering multi‐source content delivery in ICN, an issue addressed in this paper. As our contribution, we analytically quantify the average content delivery time when different cache replacement policies, namely, least recently used (LRU) and random replacement (RR) policy, are employed. As an impressive result, we report the superiority of these policies in term of the popularity distribution of contents. The expected content delivery time in a supposed network topology was studied by both theoretical and experimental method. On the basis of the obtained results, some interesting findings of the performance of used cache replacement policies are provided.
Discovery of a new family of heterocyclic amine linked plastoquinone analogs for antimicrobial evaluation
Authors: Tuyun Amaç F. , Yıldız Mahmut , Bayrak Nilüfer , Yıldırım Hatice , Mataracı Kara Emel , Jannuzzi Ayse T. , Ozbek Celik Berna
Published: August 2019

A series of aminobenzoquinones, denoted as PQ analogs (PQ1‐13), were synthesized by employing a green methodology approach using water as solvent developed by Tandon et al. Subsequently, in vitro antimicrobial potential of all PQ analogs was evaluated in a panel of seven bacterial strains (three gram positive and four gram negative bacteria) and three fungi. The antifungal profile of all PQ analogs indicated that four analogs (while PQ2, PQ9, and PQ10 were effective against Candida tropicalis, PQ11 is effective against Candida albicans) have potent antifungal activity. The results revealed that PQ9 showed similar antibacterial activity against Staphylococcus epidermidis compared clinically prevalent antibacterial drugs cefuroxime. PQ11 exhibited the highest antibacterial activity against S. epidermidis, which was about fourfold better than that of cefuroxime. Owing to their outstanding activities, PQ9 and PQ11 were chosen for a further investigation for biofilm and cytotoxicity evaluation. Based on the tests performed, there was a significant positive correlation between inhibition of the biofilm attachment and time. In addition, PQ9 and PQ11 showed cytotoxic effects at high concentrations on Balb/3T3, HaCaT, HUVEC, and NRK‐52E cells (>24 and >18 μg/mL, respectively). Thus, two analogs (PQ9 and PQ11) were identified as the hits with the strong antibacterial efficiency against the S. epidermidis with low MIC values.
Evaluation of body mass index as a prognostic indicator from two rough‐toothed dolphin (Steno bredanensis) mass strandings in Florida
Authors: Karns Bree L. , Ewing Ruth Y. , Schaefer Adam M.
Published: August 2019

Rough‐toothed dolphins (Steno bredanensis) are a common mass stranding species in Florida. These large stranding events typically include a small number of sick or injured individuals and a much larger number of healthy individuals, making rapid triage essential. Little data exist on rehabilitation outcomes, and historically, successful outcomes are limited. Furthermore, very little data exist on the feeding habits and dietary needs of this species. This study compared morphology and body mass index (BMI) in two rough‐toothed dolphin mass stranding events in Florida: August 2004 (n = 36) and March 2005 (n = 32). The two groups were significantly different in morphologic measurements, with age and gender‐adjusted intake BMI significantly (p < .01) different (2004 = 0.34 ± 0.02; 2005 = 0.41 ± 0.02) between groups. Ten animals from 2005 had weights tracked throughout the rehabilitation process and demonstrated an initial drop in BMI followed by an increase and a plateau prior to release. When comparing initial BMI by stranding outcome, individuals that were rehabilitated and released had a significantly (p = .03) higher BMI than individuals who were euthanized. However, there was no difference between dolphins that died of natural causes (p = .56) and animals successfully rehabilitated. Analysis of BMI can be a useful marker in triage during a stranding, when resources are limited to identify individuals most likely to survive, as well as in determining the appropriate body condition for release. The data reported here can provide guidance on evaluating the nutritive status on this uncommon species that would otherwise be difficult to obtain among wild populations.
Construction of Spiro[indoline‐3,3′‐pyridazines] and Spiro[indene‐2,3′‐pyridazines] via TEMPO‐Mediated Oxidative Aza‐Diels‐Alder Reactions
Authors: Ye Rong , Yan Chao‐Guo
Published: August 2019

A TEMPO promoted oxidative aza‐Diels‐Alder reaction of ketohydrazones with 3‐methyleneoxindoles or 2‐arylidene‐1,3‐indanediones were successfully developed, This reaction provided an efficient synthetic protocol for novel functionalized spiro[indoline‐3,3′‐pyridazines] and spiro[indene‐2,3′‐pyridazines]. This reaction showed high diastereoselectivity and strict substituent's electron effect, which might be due to the reaction mechanisms process including sequential oxidative generation of 1,2‐diaza‐1,3‐dien and normal electron‐demand aza‐Diels‐Alder reaction.
Carbon‐ and SO2‐Locked Diarylnitroxides: Quantum Chemical Consideration, Synthesis, and Electrochemistry
Authors: Levitskiy Oleg A. , Dulov Dmitry A. , Bogdanov Alexey V. , Magdesieva Tatiana V.
Published: August 2019

Selection of linkers connecting two phenyl rings as a part of molecular design of diarylnitroxides with increased kinetic stability of redox forms was performed using quantum chemical estimation of the geometry and oxidation potential values. It revealed that introduction of the carbon bridge cannot be considered as efficient “instrument” for structural tuning of the nitroxide properties since altering neither the length of the bridge nor its position results in significant changes in the oxidation potential, in contrast to a heteroatomic bridge, which makes more perturbation in the electronic structure of diarylnitroxide. To support the prediction, new SO2‐bridged diarylnitroxide was synthesized and characterized using spectral and electrochemical methods. It is extremely stable in benzene solution, exhibits the maximal anodic potential value achieved for reversibly oxidized nitroxides to date (1.33 V, Ag/AgCl/KCl) and seems promising as cathodic redox active material providing maximal potential gap as compared to the previously reported compounds.
One‐Pot Synthesis of 3‐Sulfenyl/Selenylimidazo[1,5‐a]quinolines from 2‐Methylquinolines, Aliphatic Amines/Amino Acids, and Dichalcogenides
Authors: Sandeep Mummadi , Muzaffar‐ur‐Rehman MD. , Pradeep Kumar Geetala , Sridhar Balasubramanian , Reddy Kallu Rajender
Published: August 2019

One‐pot sulfenylation/selenylation reaction have been developed to access 3‐sulfenyl/selenylimidazo[1,5‐a]quinolines from 2‐methylquinolines, aliphatic amines/amino acids and dichalcogenides. This developed method gives direct access to 3‐chalcogenylimidazo[1,5‐a]quinolines in moderate to good yields with good functional group tolerance from readily available starting materials. Moreover, this protocol can avoid the prior synthesis of fused imidazoles as starting materials for the synthesis of 3‐chalcogenylimidazo[1,5‐a]quinolines. Further, we have shown synthetic utility of 3‐sulfenylimidazo[1,5‐a]quinolines with m‐CPBA to afford corresponding sulfones in good to excellent yields.
Ultrasensitive Organic Humidity Sensor with High Specificity for Healthcare Applications
Authors: Bahuguna Gaurav , Adhikary Vinod S. , Sharma Rakesh K. , Gupta Ritu
Published: August 2019

Humidity sensors have gained immense importance as non‐invasive, wearable healthcare devices for personal care as well as disease diagnostics. However, non‐specificity, poor stability at extreme conditions, and low sensitivity of the humidity sensor inhibit its usage as a health monitoring device. In the present study, N−F containing organic molecule, SelectfluorTM (F‐TEDA) based humidity sensors with ∼1–2 mm long needle‐shaped crystals is fabricated on interdigitated electrodes resulting in excellent performance. The unidirectional growth of crystals led to the formation of a conduction pathway for water molecules across the crystal, which otherwise are non‐conducting. The as‐fabricated humidity sensor at an operational voltage of 0.8 V displays a sensitivity of six orders in magnitude, best reported so far. The sensor does not exhibit any response upon exposure to various volatile organic compounds and reactive gases, indicating remarkable specificity. The sensor is tolerant to high moisture of 95 % for prolonged hours followed by monitoring over several days and degrades to 50 % of its original sensitivity only after continuous exposure for several days. Electrochemical impedance spectroscopy (EIS) shows reversal from resistive to capacitive behavior with increasing humidity levels. The fabricated humidity sensor acts as a healthcare device for breath rate monitoring and touch‐free examination of skin moisture.
Assessment of Pig‐a, Micronucleus, and Comet Assay Endpoints in Tg.RasH2 Mice Carcinogenicity Study of Aristolochic Acid I
Authors: Chen Ruixue , Zhou Changhui , Cao Yiyi , Xi Jing , Ohira Toko , He Liang , Huang Pengcheng , You Xinyue , Liu Weiying , Zhang Xinyu , Ma Shuangcheng , Xie Tianpei , Chang Yan , Luan Yang
Published: August 2019

A newly developed in vivo Pig‐a gene mutation assay displays great potential for integration into genotoxicity tests. To obtain more evidence for application of the Pig‐a assay, we integrated this assay, micronucleus test in peripheral blood (MN‐pb test) and bone marrow (MN‐bm test), as well as a Comet assay into a transgenic RasH2 mice carcinogenicity study. Fourteen male RasH2 mice and five wild‐type (WT) mice were treated with a strong mutagen aristolochic acid I at a dose of 5 mg/kg/day for 4 consecutive weeks. Mice recovered in 5 weeks. Peripheral bloods were collected for Pig‐a assay, MN‐pb test, and Comet assay at several time points, while bone marrow and target organs were harvested for the MN‐bm test and pathological diagnosis after mice were euthanized. Finally, 13 of the 14 RasH2 mice developed squamous cell carcinomas in the forestomach, while there were no carcinomas in the WT mice. Pig‐a mutant frequencies (MFs) consecutively increased throughout the study to a maximum value of approximately 63‐fold more than background. These frequencies were relative to the incidence, size, and malignant degree of tumors. Micronucleated reticulocytes increased from Day 1 to Day 49, before returning to background levels. No positive responses were observed in either the MN‐bm test or the Comet assay. Results suggested that, when compared with the other two tests, the Pig‐a assay persistently contributed to sustaining MFs, enhanced detection sensitivity due to the accumulation of Pig‐a mutations, and demonstrated better predictability for tumorigenicity. Environ. Mol. Mutagen. 61:266–275, 2020. © 2019 Wiley Periodicals, Inc.
The Enhanced Photovoltaic Performance of Sb2S3 Solar Cells by Thermal Decomposition of Antimony Ethyl Xanthate with Thiourea Doping
Authors: Li Jihong , Liu Xiaolong , Yao Jianxi
Published: August 2019

The thermal decomposition method is regarded as a simple and effective way to prepare Sb2S3 films. Herein, Sb2S3 films are prepared by thermal decompositions of antimony ethyl xanthate (Sb(xt)3). During the thermal decompositions process, sulfur vacancy defects are easily formed because of high temperatures. To reduce the sulfur vacancy defects in the final Sb2S3 films, thiourea (TU) is introduced in the Sb(xt) precursor. By doping with TU, the crystallinity of the Sb2S3 films improves and dense Sb2S3 films are formed. With the decrease in sulfur defects, the carrier concentrations are greatly increased from 2.5 × 1016 to 6.2 × 1016 cm−3. Compared with the no‐doping Sb2S3 solar cells, the power conversion efficiency of Sb2S3 solar cells with doping 25% TU is improved from 2.85% to 3.70%.
Spatio‐temporal classification in point patterns under the presence of clutter
Authors: Siino Marianna , Rodríguez‐Cortés Francisco J. , Mateu Jorge , Adelfio Giada
Published: August 2019

We consider the problem of detection of features in the presence of clutter for spatio‐temporal point patterns. In previous studies, related to the spatial context, Kth nearest‐neighbor distances to classify points between clutter and features. In particular, a mixture of distributions whose parameters were estimated using an expectation‐maximization algorithm. This paper extends this methodology to the spatio‐temporal context by considering the properties of the spatio‐temporal Kth nearest‐neighbor distances. For this purpose, we make use of a couple of spatio‐temporal distances, which are based on the Euclidean and the maximum norms. We show close forms for the probability distributions of such Kth nearest‐neighbor distances and present an intensive simulation study together with an application to earthquakes.
Submarine platform development by erosion of a Surtseyan cone at Capelinhos, Faial Island, Azores
Authors: Zhao Zhongwei , Mitchell Neil C. , Quartau Rui , Tempera Fernando , Bricheno Lucy
Published: August 2019

Erosion of volcanic islands ultimately creates shallow banks and guyots, but the ways in which erosion proceeds to create them over time and how the coastline retreat rate relates to wave conditions, rock mass strength and other factors are unclear. The Capelinhos volcano was formed in 1957/58 during a Surtseyan and partly effusive eruption that added an ~2.5 km2 tephra and lava promontory to the western end of Faial Island (Azores, central North Atlantic). Subsequent coastal and submarine erosion has reduced the subaerial area of the promontory and created a submarine platform. This study uses historical information, photos and marine geophysical data collected around the promontory to characterize how the submarine platform developed following the eruption. Historical coastline positions are supplemented with coastlines interpreted from 2004 and 2014 Google Earth images in order to work out the progression of coastline retreat rate and retreat distance for lava‐ and tephra‐dominated cliffs. Data from swath mapping sonars are used to characterize the submarine geometry of the resulting platform (position of the platform edge, gradient and morphology of the platform surface). Photographs collected during SCUBA and ROV dives on the submarine platform reveal a rugged surface now covered with boulders. The results show that coastal retreat rates decreased rapidly with time after the eruption and approximately follow an inverse power‐law relationship with coastal retreat distance. We develop a finite‐difference model for wave attenuation over dipping surfaces to predict how increasing wave attenuation contributed to this trend. The model is verified by reproducing the wave height variation over dipping rock platforms in the UK (platform gradient 1.2° to 1.8°) and Ireland (1.8°). Applying the model to the dipping platform around Capelinhos, using a diversity of cliff resistance predicted from known lithologies, we are able to predict erosion rate trends for some sectors of the edifice. We also explore wider implications of these results, such as how erosion creates shallow banks and guyots in reef‐less mid‐oceanic archipelagos like the Azores. © 2019 John Wiley & Sons, Ltd. © 2019 John Wiley & Sons, Ltd.
Petrography of detrital zircons from sandstones of the Lower Devonian Accraian Formation, SE Ghana: Implications on provenance
Authors: Anani Chris Y. , Anim Richard O. , Armah Benjamin N. , Atichogbe Joseph F. , Sakyi Patrick Asamoah , Mahu Edem , Asiedu Daniel K.
Published: August 2019

Integrated petrographic studies entailing quartz‐type analysis and zircon typologic studies were carried out on sandstones of the Lower Devonian Accraian Formation of southern Ghana to constrain their provenance and tectonic setting. The stratigraphic succession of the Devonian Accraian Group consists mainly of sandstones in the Lower Accraian Formation, shales in the Middle Accraian Formation, and sandstone–shale intercalations in the Upper Accraian Formation. Systematic sampling of sandstones was conducted in the Lower Devonian Accraian Formation. Modal petrographic analysis indicates that the sandstones are quartz arenites with their framework grains consisting on average of, 99.8% quartz, 0.14% lithics with little or no feldspars. They are subangular to subrounded in shape. Modal mineralogy of the sandstones suggests that they are of craton interior origin with an affinity to recycled orogenic provenance. Quartz‐type analysis was used to unravel distinct characteristic features of the quartz grain, namely its polycrystallinity, nonundulose, and undulose nature to constrain the source rock. This pointed to multiple sediment supply from both a plutonic origin and a medium‐ to high‐grade metamorphic terrain. Furthermore, a comprehensive zircon typology study on 298 zircon grains indicate multiple provenances of calc‐alkaline affinity. This study revealed that the Lower Accraian Formation sandstones probably received sediment input from the Paleoproterozoic Birimian Basin granitoids and their associated metasedimentary rocks and some additional supply from the Neoproterozoic sedimentary rocks from the Volta Basin which are inclusive of sediments derived from the Dahomeyide Belt of the Pan‐African Orogeny.
Exploring the psychometric properties of the CES‐D‐10 and its practicality in detecting depressive symptomatology in 27 low‐ and middle‐income countries
Authors: James Caryl , Powell Marvin , Seixas Azizi , Bateman André , Pengpid Supa , Peltzer Karl
Published: August 2019

The Center for Epidemiological Studies Depression‐10 (CES‐D‐10) scale is known for its good psychometric properties in measuring depressive symptoms, however, some researchers question its applicability across various settings. This study explored the factor structure of the CES‐D‐10 in low‐ and middle‐income countries (LMICs). This cross‐sectional survey consisted of 16,723 university students across 27 LMICs that completed self‐report instruments assessing socio‐demographic information and depressive symptoms using the CES‐D‐10. Data analysis included: exploratory factor analysis, item response theory and differential item functioning. Results indicate that a two‐factor model (depressive affect and positive affect) had the best fit for this population and accounted for 52% of the total observed variance with an internal consistency, α = .77 for the depressive affect items and α = .57 for the positive affect items. The graded response model (GRM), however, indicated that the depressive affect factor had a good fit, unlike the positive affect factor. The depressive affect factor was found to consistently model depression for females better than males. Relative to their Asian counterparts, African, Caribbean and South American participants of similar depressive affect responded differently on all items of the depressive affect factor. The depressive affect factor seems most ideal for LMICs and shows gender and cross‐cultural variability.
Primary Bone Tumors: Challenges and Opportunities for CAR-T Therapies
Authors: Folkert Ian W , Devalaraja Samir , Linette Gerald P , Weber Kristy , Haldar Malay
Published: August 2019

Primary malignant bone tumors are rare, occur in all age groups, and include distinct entities such as osteosarcoma, Ewing sarcoma, and chondrosarcoma. Traditional treatment with some combination of chemotherapy, surgery, and radiation has reached the limit of efficacy, with substantial room for improvement in patient outcome. Furthermore, genomic characterization of these tumors reveals a paucity of actionable molecular targets. Against this backdrop, recent advances in cancer immunotherapy represent a silver lining in the treatment of primary bone cancer. Major strategies in cancer immunotherapy include stimulating naturally occurring anti-tumor T cells and adoptive transfer of tumor-specific cytotoxic T cells. Chimeric antigen receptor T cells (CAR-T cells) belong to the latter strategy and are an impressive application of both insights into T cell biology and advances in genetic engineering. In this review, we briefly describe the CAR-T approach and discuss its applications in primary bone tumors. © 2019 American Society for Bone and Mineral Research.
TGFβ Inhibition Stimulates Collagen Maturation to Enhance Bone Repair and Fracture Resistance in a Murine Myeloma Model
Authors: Green Alanna C , Lath Darren , Hudson Katie , Walkley Brant , Down Jennifer M , Owen Robert , Evans Holly R , Paton-Hough Julia , Reilly Gwendolen C , Lawson Michelle A , Chantry Andrew D
Published: August 2019

Multiple myeloma is a plasma cell malignancy that causes debilitating bone disease and fractures, in which TGFβ plays a central role. Current treatments do not repair existing damage and fractures remain a common occurrence. We developed a novel low tumor phase murine model mimicking the plateau phase in patients as we hypothesized this would be an ideal time to treat with a bone anabolic. Using in vivo μCT we show substantial and rapid bone lesion repair (and prevention) driven by SD-208 (TGFβ receptor I kinase inhibitor) and chemotherapy (bortezomib and lenalidomide) in mice with human U266-GFP-luc myeloma. We discovered that lesion repair occurred via an intramembranous fracture repair-like mechanism and that SD-208 enhanced collagen matrix maturation to significantly improve fracture resistance. Lesion healing was associated with VEGFA expression in woven bone, reduced osteocyte-derived PTHrP, increased osteoblasts, decreased osteoclasts, and lower serum tartrate-resistant acid phosphatase 5b (TRACP-5b). SD-208 also completely prevented bone lesion development in mice with aggressive JJN3 tumors, and was more effective than an anti-TGFβ neutralizing antibody (1D11). We also discovered that SD-208 promoted osteoblastic differentiation (and overcame the TGFβ-induced block in osteoblastogenesis) in myeloma patient bone marrow stromal cells in vitro, comparable to normal donors. The improved bone quality and fracture-resistance with SD-208 provides incentive for clinical translation to improve myeloma patient quality of life by reducing fracture risk and fatality. © 2019 American Society for Bone and Mineral Research.
Green, rapid, and highly efficient syntheses of α,α′‐bis[(aryl or allyl)idene]cycloalkanones and 2‐[(aryl or allyl)idene]‐1‐indanones as potentially biologic compounds via solvent‐free microwave‐assisted Claisen–Schmidt condensation catalyzed by MoCl5
Authors: Bakhshi Reza , Zeynizadeh Behzad , Mousavi Hossein
Published: August 2019

A new, green, and highly efficient protocol for the expeditious preparation of some α,α′‐bis[(aryl or allyl)idene]cycloalkanones and 2‐[(aryl or allyl)idene]‐1‐indanones via a simple microwave‐assisted Claisen–Schmidt condensation reaction catalyzed by MoCl5 was successfully developed. Outstanding features of the current methodology include the use of solvent‐free conditions, simple operation, use of a very inexpensive and available catalyst, low catalyst loading, short reaction times, high yields of the pure products, no harmful by‐products, easy workup, and also the applicability of microwave irradiation as a clean source of energy. Furthermore, a gram‐scale reaction was successfully conducted, proving the scalability of this current Claisen–Schmidt condensation reaction.
Flexible gold nanoparticles/rGO and thin film/rGO papers: novel electrocatalysts for hydrogen evolution reaction
Authors: Topçu Ezgi , Dağcı Kıranşan Kader
Published: August 2019

BACKGROUND

Fabrication of cost‐effective and durable materials for efficient hydrogen production in splitting water (hydrogen evolution reaction) is of importance for the successful utilization of hydrogen‐based green energy technologies. Therefore, electrocatalytic materials have been designed with a simple approach using electrodeposition of gold nanoparticles (AuNPs) and thin film (AuTF) directly on reduced graphene oxide (rGO) paper. As‐prepared paper electrocatalysts (AuNPs/rGO and AuTF/rGO) were characterized by X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM).

RESULTS

Free‐standing and flexible AuNPs/rGO and AuTF/rGO electrocatalysts have exhibited excellent performances on HER with low Tafel slopes (88 and 112 mV dec−1), low onset potentials (−47 and −55 mV), small overpotentials of only −176 and −204 mV to drive 10 mA cm−2, respectively, and high durability even with the rolled design. The outstanding performance of these two electrocatalysts can be attributed to the uniform distribution of 20‐nm‐sized AuNPs and the deposition of well‐ordered AuTF on rGO paper, providing an increment in the surface area and an enhancement of the electron density.

CONCLUSION

The controllable design of AuNPs/rGO and AuTF/rGO electrocatalysts, together with their high flexibility, good stability and promising results, suggest potential use in future applications of H2 production in splitting water. © 2019 Society of Chemical Industry
Platelet‐rich fibrin and collagen membrane in the preservation of the alveolar bone: Feasibility of the elemental inorganic composition and scanning electron microscopy analysis
Authors: Dias Fernando José , Arias Alain , Borie Eduardo , Fuentes Ramón
Published: August 2019

The success of dental implants is related to the amount, quality, and composition of the alveolar bone. The placement of platelet‐rich fibrin (PRF) clot associated with a resorbable collagen membrane (RCM) in a postextraction alveolus is a technique used for ridge preservation. This case report study analyzed the ultrastructural characteristics of cross‐sectioned alveolar bone that received PRF and RCM using scanning electron microscopy and the inorganic composition using “energy dispersive X‐ray spectrometry,” in order to explore the feasibility of this method to clinical studies. Three alveolar bone samples from two male patients (37 and 58 years old), obtained in the procedure of placing the dental implant, were analyzed. Two bone samples previously received PRF and RCM (M37 and M58), the third sample represented a physiological bone formation without treatment (M37‐control). The bone sample M37 showed irregularly shaped islets of calcified material intermingled with connective tissue. The other samples, from the 58‐year‐old patient with PRF and RCM (M58); and the other untreated bone sample from the same 37‐year‐old patient (M37‐control) showed similar ultrastructural morphology with trabecular conformation without islets agglomerations. The inorganic composition analysis showed higher concentrations of calcium and phosphorus in both samples treated with PRF and RCM in comparison to the untreated bone sample. The Ca/P ratio was higher in the M37 sample compared to the others samples. The results showed morphology and inorganic composition differences among the treatments used, suggesting that this method is feasible to analyze parameters of the alveolar bone tissue.