bluuebunny/crossref_metadata_2025 huggingface dataset:
A Nonfullerene Semitransparent Tandem Organic Solar Cell with 10.5% Power Conversion Efficiency
Authors: Chen Shangshang , Yao Huatong , Hu Bo , Zhang Guangye , Arunagiri Lingeswaran , Ma Lik‐Kuen , Huang Jiachen , Zhang Jianquan , Zhu Zonglong , Bai Fujin , Ma Wei , Yan He
Published: September 2018

Semitransparent organic solar cells have great potential for building integrated photovoltaics and power‐generating windows owing to their advantages of light weight, mechanical flexibility, and color tunability. However, the performance of previous semitransparent organic solar cells have been limited by their relatively weak optical absorptions. In this paper, an efficient nonfullerene semitransparent tandem organic solar cell that exhibits a broad absorption from 300 to 1000 nm is reported. The rear subcell is based on a narrow‐bandgap nonfullerene acceptor named IEICS‐4F that exhibits a strong crystallinity and high electron mobility. As a result, the IEICS‐4F‐based single‐junction opaque and semitransparent organic solar cells yield high efficiencies of 10.3% and 7.5%, respectively. To further enhance light harvesting of the single‐junction semitransparent organic solar cells while maintaining a decent transmittance, a semitransparent tandem organic solar cell is fabricated by incorporating a medium‐bandgap P3TEA:FTTB‐PDI4 blend as the front subcell. A high efficiency of 10.5% is recorded with an average transmittance of 20%.
Shortcut Scheme for One‐Step Implementation of a Three‐Qubit Nonadiabatic Holonomic Gate
Authors: Huang Bi‐Hua , Kang Yi‐Hao , Shi Zhi‐Cheng , Song Jie , Xia Yan
Published: September 2018

Nonadiabatic holonomic quantum computation has attracted increasing interest because of its robustness. Here, based on the shortcuts to adiabaticity, a scheme to construct a three‐qubit nonadiabatic holonomic gate in a cavity quantum electrodynamics system is proposed. In the scheme, the three‐qubit holonomic gate is implemented in a single step. In addition, by numerical simulations, it is shown that the constructed holonomic quantum gate holds characteristics such as high fidelity, decoherence‐resistance, and error‐immunity.
Novel 2D Germanene Dioxide Monolayers: Mechanical Properties, Hole‐Mobility Values, and Carrier Mobility
Authors: Dou Yan‐Mei , Ji Wei‐Xiao , Zhang Shu‐Feng , Zhang Chang‐Wen , Li Ping , Wang Pei‐Ji
Published: September 2018

Using first‐principles calculations, 2D germanene dioxide monolayers of freestanding and well‐ordered GeO 4 tetrahedrons (4‐GD) and GeO 6 tetrahedrons (6‐GD) building blocks are found to be stable. 4‐GD is formed by corner‐sharing GeO 4 tetrahedrons in a rectangular network, and 6‐GD consists of edge‐sharing GeO 6 octahedrons. However, the insulating 6‐GD is the strongest germanene dioxide monolayer with an energy difference of −4.93 eV, and can therefore play the role of a supporting substrate for nanostructures in sensing and catalytic applications. The bandgap of 4‐GD monolayers is 2.8 eV, and 6‐GD has slightly larger bandgaps of about 3.5 eV regardless of the chirality and width. It is found that both the imaginary part of the dielectric function and the absorption spectrum exhibit a consistent bandgap with the electronic structure diagram, suggesting the possibility of its use as an optical detector for ultraviolet light. Carrier mobility can be observed along the x and y directions; a maximum of 1.20 × 104 cm2 V−1 s−1 is observed. Their thermal stability can be confirmed by molecular dynamics at 300 and 500 K, suggesting that the novel 2D structures have a stable existence.
Facile Synthesis of a Stable Dihydroboryl {BH2}− Anion
Authors: Arrowsmith Merle , Mattock James D. , Hagspiel Stephan , Krummenacher Ivo , Vargas Alfredo , Braunschweig Holger
Published: September 2018

While the one‐electron reduction of (CAACMe)BH2Br (CAACMe=1‐(2,6‐diisopropylphenyl)‐3,3,5,5‐tetramethylpyrrolidin‐2‐ylidene) yields a hydride‐shift isomer of the corresponding tetrahydrodiborane, a further reversible reduction leads to the first stable parent boryl anion, [(CAACMe)BH2]−, which acts as a powerful boron nucleophile.
Identification of sieve elements and companion cell protoplasts by a combination of brightfield and fluorescence microscopy
Authors: Kaur Prabhjot , Gonzalez Pedro , Dutt Manjul , Etxeberria Ed
Published: September 2018

Premise of the Study

Phloem‐limited diseases are becoming increasingly pervasive, threatening the existence of crops worldwide. Studies of phloem diseases are complicated by the inaccessibility of the phloem tissue. Phloem cells are located deep inside the plant body, are interspersed with other cell types, are among the smallest cells in the plant kingdom, and make up a small percentage of the total cell population in a plant. These properties make phloem cells difficult to investigate.

Methods

We used leaf midrib protoplasts and a combination of organelle‐specific dyes including Neutral Red (acidic compartments), MitoTracker Green (mitochondria), Hoechst 3342 (nucleus), and chloroplast autofluorescence. We examined the protoplasts under light and fluorescence microscopy.

Results

When observed using brightfield and fluorescence microscopy, sieve element protoplasts were distinguished by the lack of vacuole and a nucleus, and by containing various mitochondria. Companion cells showed a dense cytoplasm and various small vacuoles. They also revealed their characteristic large nucleus and abundant mitochondria.

Discussion

We present evidence that a combination of organelle‐specific dyes and autofluorescence allows for the identification of sieve elements and companion cell protoplasts from citrus leaf tissue.
Photolithographically Patterned Hydrogels with Programmed Deformations
Authors: Li Chen Yu , Hao Xing Peng , Wu Zi Liang , Zheng Qiang
Published: September 2018

Programmed deformations are widespread in nature, providing elegant paradigms to design self‐morphing materials with promising applications in biomedical devices, flexible electronics, soft robotics, etc. In this emerging field, hydrogels are an ideal material to investigate the deformation principle and the structure‐deformation relationship. One crucial step is to construct heterogeneous structures in a facile yet effective way. Herein, we provide a focus review on different deformation modes and corresponding structural features of hydrogels. Photolithography is a versatile approach to control the outer shape of the hydrogel and spatial distribution of the component in the hydrogel, endowing the patterned hydrogels with programmed internal stress and thus controllable deformations. Specifically, cooperative deformations take place in periodically patterned hydrogels with in‐plane gradients, and multiple morphing structures are formed in one patterned hydrogel using selective preswelling to direct the buckling of each unit. The structural control strategy and deformation principles should be applicable to other materials with broad applications in diverse areas.
Composite Finite‐time Convergent Guidance Law for Maneuvering Targets with Second‐order Autopilot Lag
Authors: Wu Junxiong , Wang Hui , He Shaoming , Lin Defu
Published: September 2018

This paper aims to develop a new finite‐time convergent guidance law for intercepting maneuvering targets accounting for second‐order autopilot lag. The guidance law is applied to guarantee that the line of sight (LOS) angular rate converges to zero in finite time and results in a direct interception. The effect of autopilot dynamics can be compensated based on the finite‐time backstepping control method. The time derivative of the virtual input is avoided, taking advantage of integral‐type Lyapunov functions. A finite‐time disturbance observer (FTDOB) is used to estimate the lumped uncertainties and high‐order derivatives to improve the robustness and accuracy of the guidance system. Finite‐time stability for the closed‐loop guidance system is analyzed using the Lyapunov function. Simulation results and comparisons are presented to illustrate the effectiveness of the guidance strategy.
Determination of Penicillium griseofulvum‐oriented pyripyropene A, a selective inhibitor of acyl‐coenzyme A:cholesterol acyltransferase 2, in mouse plasma using liquid chromatography–tandem mass spectrometry and its application to pharmacokinetic studies
Authors: Lee Kyeong‐Ryoon , Chae Song‐Hee , Kim Min Ju , Chae Yoon‐Jee , Lee Myung Yeol , Lee Chang Woo , Kang Jong Soon , Yoon Won‐Kee , Won Young‐Suk , Lee Kihoon , Moon Og‐Sung , Kim Young‐Kook , Kim Hyoung‐Chin
Published: September 2018

In this study, we developed a method for the determination of Penicillium griseofulvum‐oriented pyripyropene A (PPPA), a selective inhibitor of acyl‐coenzyme A:cholesterol acyltransferase 2, in mouse and human plasma and validated it using liquid chromatography–tandem mass spectrometry. Pyripyropene A (PPPA) and an internal standard, carbamazepine, were separated using a Xterra MS C18 column with a mixture of acetonitrile and 0.1% formic acid as the mobile phase. The ion transitions monitored in positive‐ion mode [M + H]+ of multiple‐reaction monitoring (MRM) were m/z 148.0 from m/z 584.0 for PPPA and m/z 194.0 from m/z 237.0 for the internal standard. The detector response was specific and linear for PPPA at concentrations within the range from 1 to 5,000 ng/mL. The intra−/inter‐day precision and accuracy of the method was acceptable by the criteria for assay validation. The matrix effects of PPPA ranged from 97.6 to 104.2% and from 93.3 to 105.3% in post‐preparative mouse and human plasma samples, respectively. PPPA was also stable under various processing and/or handling conditions. Finally, PPPA concentrations in the mouse plasma samples could be measured after intravenous, intraperitoneal, or oral administration of PPPA, suggesting that the assay is useful for pharmacokinetic studies on mice and applicable to human studies.
UPLC–MS/MS determination of flavokawain B, a novel anti‐tumor chemotherapeutic agent in rat plasma and its application to a pharmacokinetic study in rats
Authors: Yang Xueqin , Zan Tao , Yan Huiyu , Liu Baohua
Published: September 2018

A sensitive, selective and rapid ultra‐performance liquid chromatography/tandem mass spectrometry method was developed and validated for the quantification of flavokawain B in rat plasma using myrislignan as an internal standard. Sample preparation was accomplished through a protein precipitation extraction process. Chromatographic resolution of flavokawain B and the IS was achieved on an Agilent XDB‐C18 column (2.1 × 100 mm, 1.8 μm) using a gradient mobile phase comprising 0.1% formic acid in water and acetonitrile delivered at a flow rate of 0.5 mL/min. Flavokawain B and the IS eluted at 3.27 and 1.96 min, respectively. The total chromatographic run time was 6.0 min. A linear response function was constructed in the concentration range 0.524–1048 ng/mL. Method validation was performed as per the US Food and Drug Administration guidelines and the results met the acceptance criteria. Intra‐ and inter‐day accuracy and precision were in the ranges of −14.3–13.2 and 3.4–11.8%, respectively. Flavokawain B was demonstrated to be stable under various stability conditions. This method has been applied to a pharmacokinetic study in rats.
New Dihydrostilbene Derivatives from Chloraea chrysantha
Authors: Tomassini Lamberto , Piovano Marisa , Ventrone Antonio , Pani Vincenzo , Frezza Claudio , Nicoletti Marcello
Published: September 2018

The study of the main components of the alcoholic extract obtained from Chloraea chrysantha Poepp. led to the isolation of two new dihydrostilbene derivatives together with the known gavilein (3). The new compounds have been assigned as 3‐methoxy‐5‐{2‐[3‐methoxy‐2‐(3‐methylbut‐2‐en‐1‐yl)phenyl]ethyl}phenol (1) and 1‐[2‐(3,5‐dimethoxyphenyl)ethyl]‐3‐methoxy‐2‐(3‐methylbut‐2‐en‐1‐yl)benzene (2). The presence of compounds 1–3 is perfectly in accordance with the current botanical classification of the genus.
Label‐Free Detection of Protein Tyrosine Phosphatase 1B (PTP1B) by Using a Rationally Designed Förster Resonance Energy Transfer (FRET) Probe
Authors: Durgannavar Trishaladevi , Kwon Se Jeong , Ghisaidoobe Amar B. T. , Rho Kyungmin , Kim Ju Hwan , Yoon Sun‐Young , Kang Hyo Jin , Chung Sang J.
Published: September 2018

A highly selective detection method of native protein tyrosine phosphatase 1B (PTP1B) is described using a target specific probe equipped with 1‐naphthylamine (λex=330 nm, λem=445 nm). Irradiation of a mixture of PTP1B and Probe 1 with ultraviolet light of 280 nm (corresponding to PTP1B excitation maximum) resulted in significant fluorescence increase at 445 nm, following FRET characteristics. This phenomenon does not occur with other closely related phosphatases or cellular abundant alkaline phosphatase (APP). Probe 1, the most potent and selective probe, was found to competitively inhibit PTP1B (Ki≈42 nm), whereas APP inhibition was found to be in the low micromolar range. Furthermore, Probe 1 discriminates between PTP1B and several other phosphatases. Here, we report real‐time label‐free FRET detection of pure PTP1B as well as induced human PTP1B in Escherichia coli cell lysate. In contrast to 6,8‐difluoro‐4‐methylumbelliferyl phosphate (DiFMUP), a representative fluorescence turn‐on PTP substrate, our FRET probe successfully differentiated human cervical carcinoma cell lysate, SiHa, which has a high expression level of PTP1B, from PTP1B‐knockdown SiHa cell lysate (that is, siRNA was used for PTP1B knockdown).
Dopaminergic induction of human adipose‐derived mesenchymal stem cells is accompanied by transcriptional activation of autophagy
Authors: Hasani Sanaz , Boroujeni Mahdi Eskandarian , Aliaghaei Abbas , Baghai Kaveh , Rostami Amin
Published: September 2018

Neural differentiation involves drastic morphological alterations, essentially performed by a cell‐homeostasis maintaining process known as autophagy. Here, we used the cocktail of choroid plexus epithelial cell‐conditioned medium (CPEC‐CM) and 15% knockout serum (KS) to induce human adipose‐derived mesenchymal stem cells (hASCs) into tyrosine hydroxylase (TH)‐positive neuron like cells. We showed that upon this induction, autophagy pathway was transcriptionally triggered. The expression levels of autophagy markers mTOR, BECN1, and MAP1LC3 were evidently changed throughout the dopaminergic (DAergic) differentiation of hASCs, highlighting the critical role of autophagy in this process at the level of transcription.
Ky‐2, a hybrid compound histone deacetylase inhibitor, regulated inflammatory response in LPS‐driven human macrophages
Authors: Kaneko Junya , Okinaga Toshinori , Ariyoshi Wataru , Hikiji Hisako , Fujii Seiko , Iwanaga Kenjiro , Tominaga Kazuhiro , Nishihara Tatsuji
Published: September 2018

Histone deacetylase has attracted much attention as an epigenetic factor, and the modulation of histone and transcription factor acetylation status is important for regulating gene expression. Moreover, histone deacetylase inhibitors are involved in cellular growth and differentiation. In the present study, we examined the effects of Ky‐2, a hybrid‐compound HDAC inhibitor, on inflammatory reactions and the polarization of macrophages in vitro. Human monocyte‐like THP‐1 cells were polarized to macrophage‐like cells using phorbol 12‐myristate 13‐acetate, and then polarized to M1 macrophages with LPS. Ky‐2 inhibited HDAC2 expression and enhanced the acetylation of histone H3 in THP‐1 cells. It also downregulated the expression of the IL‐1β‐encoding gene and the LPS‐induced phosphorylation of p38 mitogen‐activated protein kinases in THP‐1 cells. Moreover, the expression of nod‐like receptor protein 3 and cleaved caspase‐1 p20 was downregulated in Ky‐2‐treated THP‐1 cells. In contrast, this agent upregulated the expression of IL‐1ra in LPS‐treated THP‐1 cells. These results indicate that Ky‐2‐treatment downregulates the expression of the inflammatory cytokine, IL‐1β, in LPS‐treated THP‐1 cells, suggesting that Ky‐2 might regulate M1 macrophage polarization through the suppression of inflammatory responses such as NLRP3 inflammasome activation.
Dentoalveolar fracture: A complication of extraction of upper left first molar
Authors: Tay Zhuo Wei , Zakaria Sarah Sabrina , Zamhari Ahmad Khairuddin , Lee Sie Wei
Published: September 2018

Key Clinical Message

The current trend of managing maxillary tuberosity fractures is traumatic and results in the loss of bone and teeth. Treatment options that chose to retain the fractured segments and teeth have been perceived to be unfavorable. This case report shows that maxillary tuberosity fractures can be treated conservatively.
Intrinsic Electrocatalytic Activity of Gold Nanoparticles Measured by Single Entity Electrochemistry
Authors: Peng Yue‐Yi , Guo Dan , Ma Wei , Long Yi‐Tao
Published: September 2018

Understanding the real nature of the intrinsic electrocatalytic performance of the counter electrode is crucial for realizing high conversion efficiency of solar energy in photoelectric devices. However, owing to the average effects, a thorough insight into such electrocatalytic process remains challenging in ensemble measurements. Here, we realized the real‐time detection of electrocatalytic reduction of a single Au nanoparticle (NP) in sulfide/polysulfide redox electrolyte solution using single entity collision electrochemistry. Owing to the high‐sensitivity electrochemical measurement, size‐dependent electrocatalytic behaviors of polysulfide reduction were observed for single AuNP collision. Our approach allowed the electrocatalytic properties of AuNPs for polysulfide electrolyte reduction at the single NPs level to be quantified, and the turnover number as a function of particle size were further estimated. Our result has further pointed out the importance of NP size control in the electrocatalysis study.
Electrocatalytic Reduction of Hydrogen Peroxide by Pd−Ag Nanoparticles Based on the Collisional Approach
Authors: Li Mingzhi , Ge Zhiqiang , Zhang Shudong , He Peng , Gu Yaxiong , Qi Limin , Shao Yuanhua
Published: September 2018

Particles collision onto a surface or an interface is a novel electrochemical approach, which can be used to investigate the behavior of single entities. Benefiting from advantages including single particle/single event resolution, label‐free detection and high sensitivity, this technique has been widely employed in the study of electrocatalytic amplification of detection signal by nanoparticles. Herein, we report the investigation of the collisional electrocatalytic behaviors of novel Pd−Ag hyperbranched nanoparticles through the observation of catalysis of hydrogen peroxide (H2O2) oxidation. The newly prepared Pd−Ag hyperbranched nanoparticles have been characterized by cyclic voltammetry and surface techniques. They can obviously reduce the overpotential of the reduction of H2O2 and show the high electrocatalytic activity. When the nanoparticles collide onto the electrode via the Brownian random motion, electrocatalytic reaction occurs and results in significant current increases, which could provide information about nanoparticles and electrochemical reactions. Furthermore, concentration and potential dependence are also investigated in detail, which confirms the reliability and universality of this methodology as an ultra‐sensitive probe. Based on these results, it is clearly shown that such platform is promising in further applications for biosensing and single nanoparticle analysis.
Synthetic Strategies and Structural Arrangements of Isoreticular Mixed‐Component Metal–Organic Frameworks
Authors: Bitzer Johannes , Kleist Wolfgang
Published: September 2018

In recent years, the synthesis of mixed‐metal and mixed‐linker metal–organic frameworks with multiple metals and/or linker molecules combined in one framework has become a growing field of interest. These mixed‐component or multivariate metal–organic framework materials provide the possibility to introduce multiple functionalities inside one framework. The interaction of guest molecules with different functionalities in the same material is a promising approach in the fields of gas storage, separation, catalysis and drug delivery. Furthermore, the combination of different components may lead to synergistic effects that cannot be achieved otherwise. These mixed‐component approaches open up new pathways to an even larger range of possible customizations in the field of metal–organic frameworks.
Synthesis of chiral salalen ligands and their in‐situ generated Cu‐complexes for asymmetric Henry reaction
Authors: Dixit Ashish , Kumar Pramod , Singh Surendra
Published: September 2018

Chiral salalen ligands derived from (S)‐proline and derivatives of salicyaldehydes were synthesized, and their in‐situ generated Cu (II) complexes were evaluated in the asymmetric Henry reaction. Salalen ligand of different substituents on the phenyl moiety showed remarkable effect on the enantioselectivity of nitro‐aldol product of 4‐nitrobenzaldehyde and nitromethane. Cu (II) complex generated in situ with (S)‐2‐(tert‐butyl)‐6‐((2‐(((2‐hydroxy‐3‐methylbenzylidene)amino)methyl)pyrrolidin‐1‐yl)methyl) phenol (10 mol%) and Cu (OAc)2.H2O (10 mol%), found to be better catalyst for nitro‐aldol reaction between 4‐nitrobenzaldehyde and nitromethane, gave corresponding product in 85% yield and 88% enantiomeric excess (ee) in isopropanol at 35°C after 40 hours. The catalyst also used for the Henry reaction with different substituted benzaldehydes and corresponding products were obtained in 22% to 99% yields with 66% to 92% ee. Henry reaction of 4‐nitrobenzaldehyde and prochiral nitroethane gave anti‐selective product (dr = 79/21; anti/syn) in a 91% yield with 80% ee.
Insights into Noncovalent Binding Obtained from Molecular Dynamics Simulations
Authors: Baz Jörg , Gebhardt Julia , Kraus Hamzeh , Markthaler Daniel , Hansen Niels
Published: September 2018

The key to nanoscale control of physical, chemical, and biological processes lies in well‐founded models of noncovalent binding. Atomistic simulations probe the free‐energy surface underlying molecular assembly processes in solution. Two examples of noncovalent binding studied by molecular dynamics simulations are discussed, the dimerization of a water‐soluble perylene bisimide derivative in aqueous solution with a focus on the influence of solvent composition on the aggregation strength and the binding of 1‐butanol to α‐cyclodextrin at infinite dilution with the focus on the determination of method‐independent binding free energies.
Lernzuwachs in Blended‐Learning Laborpraktika transparent machen – Feedbackfunktionen des LMS erweitern
Authors: Hedtrich Sebastian , Graulich Nicole
Published: September 2018

Blended‐Learning‐Ansätze werden schon seit einiger Zeit in unterschiedlichen Lehr‐ und Lernformaten eingesetzt. Darunter auch Laborpraktika, zu denen sich die Studierenden online selbstständig vorbereiten können. Dabei werden Inhalte und Lernkontrollen über ein Lern‐Management‐System (LMS) angeboten. Bisher sind die Möglichkeiten der LMS noch unzureichend, um den Studierenden ein Feedback zu ihrem Lernzuwachs anzubieten. Mit einer neu entwickelten Software ist es uns erstmals möglich diesen Lernprozess zeitlich mitzuverfolgen. Die elektronische Lernkontrolle wird damit zu mehr als nur einem bloßen Ersatz für die Eingangskolloquien der Laborpraktika. Denn die Software nutzt die Daten der Lernkontrollen, um den Studierenden einen Einblick in ihren individuellen Lernzuwachs zu geben. Ein Feedback‐Text über Stärken und Schwächen kann schnell generiert und versendet werden.
Prolonged electromechanical delay as an early predictor of trastuzumab‐induced cardiotoxicity in patients undergoing treatment for breast cancer
Authors: Choe Jeong Cheon , Choi Jung Hyun , Choi Jong Hyun , Ahn Jinhee , Park Jin Sup , Lee Hye Won , Oh Jun‐Hyok , Lee Han Cheol , Cha Kwang Soo , Hong Taek Jong
Published: September 2018

Background

We aimed to investigate if left ventricular electromechanical delay (LVEMD) prolongation predicts trastuzumab‐induced cardiotoxicity (TIC) in breast cancer patients.

Hypothesis

LVEMD prolongation on serial echocardiograms could be an indicator of subclinical TIC.

Methods

We included 237 breast cancer patients receiving trastuzumab chemotherapy, who underwent echocardiography at baseline and at 6 and 12 months after trastuzumab initiation. LVEMD was defined as the time from electrical activation to myocardial contraction. TIC was defined as left ventricular ejection fraction (LVEF) worsening to <55%, either as symptomatic decrease of ≥5% or asymptomatic decrease of ≥10%.

Results

During a mean follow‐up of 547 days, TIC occurred in 27 patients (11.4%). Changes in the time intervals from QRS onset on electrocardiography to the beginning and peak of transaortic flow on pulsed‐wave Doppler echocardiography (ie, ΔLVEMDi and ΔLVEMDp, respectively) were independent predictors of TIC. On receiver operating characteristic curve analysis, the optimal cutoff value for TIC prediction was 23 milliseconds for ΔLVEMDi (sensitivity, 0.85; specificity, 0.78; area under the curve [AUC], 0.882) and 21 milliseconds for ΔLVEMDp (sensitivity, 0.96; specificity, 0.68; AUC, 0.860). The C‐index for TIC prediction increased significantly after adding ΔLVEMDi and ΔLVEMDp to conventional models that included clinical variables, baseline LVEF, and changes in global longitudinal peak systolic strain. Similarly, adding ΔLVEMDi or ΔLVEMDp to conventional models provided significant improvement in discrimination capability for TIC prediction (integrated discrimination improvement and continuous net reclassification improvement index).

Conclusion

ΔLVEMDi and ΔLVEMDp may serve as predictors of subclinical cardiac dysfunction in breast cancer patients receiving trastuzumab.
Vitamin D deficiency and electrocardiographic subclinical myocardial injury: Results from National Health and Nutrition Examination Survey‐III
Authors: Ahmad Muhammad I. , Chevli Parag A. , Li Yabing , Soliman Elsayed Z.
Published: September 2018

Background

Association of cardiovascular disease (CVD) with nontraditional risk factors such as vitamin D deficiency has been examined previously. An investigation of the association of vitamin D with subclinical myocardial injury (SC‐MI) based on an electrocardiographic score is a simple, cost‐effective and innovative way to explore this relationship.

Hypothesis

We hypothesize that low vitamin D levels will be associated with prevalent SC‐MI independent of traditional CVD risk factors, lifestyle factors, and socioeconomic status.

Methods

This analysis included 6079 participants (58.3 ± 13.1 years; 54.1% women) without CVD from the third National Health and Nutrition Examination Survey. A multivariable logistic regression model was used to examine the association between vitamin D categories (<20, 20‐29, and >30 ng/mL (reference) and cardiac injury score.

Results

There was an incremental increase in the prevalence of SC‐MI across vitamin D categories with the highest prevalence in <20 ng/mL, followed by 20 to 29 ng/mL and then >30 ng/mL (trend P‐value <0.0001). There was a statistically significant association between vitamin D deficiency (<20 ng/mL) and SC‐MI (odds ratio [OR] (95% confidence interval [CI]): 1.27 (1.04‐1.55), P = 0.04). This association was stronger in men than women (OR (95% CI): 1.74 (1.32‐2.30) vs 0.94 (0.70‐1.25) respectively; interaction P‐value 0.002).

Conclusions

Vitamin D deficiency is associated with SC‐MI, especially in men. These findings may further highlight the role of nontraditional risk factors in the development of CVD. The value of vitamin D supplementation in the prevention of myocardial ischemia and injury may warrant investigation.
Direct Evidence of the Benzylium and Tropylium Cations as the Two Long‐Lived Isomers of C7H7+
Authors: Jusko Pavol , Simon Aude , Banhatti Shreyak , Brünken Sandra , Joblin Christine
Published: September 2018

Disentangling the isomeric structure of C7H7+ is a longstanding experimental issue. We report here the full mid‐infrared vibrational spectrum of C7H7+ tagged with Ne obtained with infrared‐predissociation spectroscopy at 10 K. Saturation depletion measurements were used to assign the contribution of benzylium and tropylium isomers and demonstrate that no other isomer is involved. Recorded spectral features compare well with density functional theory calculations. This opens perspectives for a better understanding and control of the formation paths leading to either tropylium or benzylium ions.
Magneto‐Controlled Biocatalytic Cascades with Logically Processed Input Signals – Substrate Channeling versus Free Diffusion
Authors: Filipov Yaroslav , Zakharchenko Andrey , Minko Sergiy , Katz Evgeny
Published: September 2018

Magnetic nanoparticles (MNPs) functionalized with various enzymes (amyloglucosidase, glucose oxidase and horseradish peroxidase) were used to perform biocatalytic cascades in two different states, solute suspension or aggregated, produced in the absence or presence of an external magnetic field. The biocatalytic reactions proceeded through bulk solution diffusion of intermediate substrates or substrate channeling, when the systems were dispersed or aggregated, respectively. The both pathways have shown very similar kinetics, unless the intermediate substrate was consumed by an additional biocatalytic process called “filter” for brevity. In the presence of the “filter” process, the diffusional process in the bulk solution was significantly inhibited, while the process based on the substrate channeling was still active. The systems were switched reversibly between the inhibited dispersed state and the active aggregated state by removing and applying the external magnetic field, respectively. The signal‐controlled biocatalytic cascades were considered as Boolean logic circuits with the inputs consisting of biomolecules and the magnetic field on‐off.
Proximity Ligation Assay (PLA)
Authors: Alam Muhammad S.
Published: September 2018

Proximity ligation assay (PLA), also referred to as Duolink® PLA technology, permits detection of protein‐protein interactions in situ (at distances <40 nm) at endogenous protein levels. It exploits specific antibodies identifying (either directly or indirectly) the two proteins of interest and utilizes specific DNA primers covalently linked to the antibodies. A hybridization step followed by DNA amplification with fluorescent probes permit visualization of spots of proximity by fluorescence microscopy. Since the development of PLA in 2002, it has been increasingly used to detect the interaction between two proteins with high sensitivity and specificity. It is a simple and sensitive technique to study protein‐protein interaction in cells. © 2018 by John Wiley & Sons, Inc.
Enantioselective Activity of Hemin in Supramolecular Gels Formed by Co‐Assembly with a Chiral Gelator
Authors: Wang Song , Jiang Hejin , Zhang Li , Jiang Jian , Liu Minghua
Published: September 2018

Supramolecular co‐assembly provides an efficient way to combine structural and functional units through noncovalent interactions and produce materials with enhanced performance. Here, using a chiral amphiphilic histidine derivative (LHC18 or DHC18) as a gelator, we have successfully co‐assembled the gelator and hemin through gelation. During the co‐assembly, the chiral information of the gelator was transcribed into the assemblies, and thus right‐ and left‐handed helical ribbons from LHC18‐Hemin and DHC18‐Hemin co‐assemblies were obtained, respectively, which were confirmed by CD spectra and SEM observations. These helical ribbons were used as artificial enzymes to catalyse the oxidation reaction of 3,4‐dihydroxy‐L‐phenylalanine (L‐DOPA). The catalytic activity of hemin in supramolecular gels can be effectively enhanced over that of free hemin. Moreover, by virtue of induced chirality, the supramolecular gels of LHC18‐Hemin and DHC18‐Hemin exhibited obvious enantioselective activity. This work provides a way to combine chirality transfer and supramolecular asymmetric catalysis.
Pulsed Electrodeposition of Co3O4 Nanocrystals on One‐Dimensional ZnO Scaffolds for Enhanced Electrochemical Water Oxidation
Authors: Wu Hao , Li Shangyi , Lu Xinxin , Toe Cui Ying , Chung Hoi Ying , Tang Yiming , Lu Xunyu , Amal Rose , Li Laisheng , Ng Yun Hau
Published: September 2018

Invited for this month's cover are the collaborative groups of Dr. Yun Hau Ng at University of New South Wales, Australia and Dr. Yiming Tang at South China Normal University, China. The front cover picture shows ultrathin Co3O4 nanoflakes that are deposited on ZnO nanorods by pulsed electrodeposition. The performance of the nanostructured hybrid Co3O4/ZnO anode in electrochemical O2 evolution is better than that of neat Co3O4. Well‐aligned one‐dimensional ZnO nanorod arrays are integrated as a scaffold which functions as a “highway” to facilitate improved charge transfer, while the porosity of the anode material allows the penetration of the electrolyte, thus promoting efficient utilization of the catalytically active species. Read the full text of the article at 10.1002/cplu.201800218.
Vacuum‐Assisted Technique to Modify the SR Method for Unidirectional Crystal Growth
Authors: Saranraj Arumugam , Jenipriya Anthony Samy , Sahaya Jude Dhas Sathiyadhas , Jose Michael , Martin Britto Dhas Sathiyadhas Amalapusham
Published: September 2018

The design and fabrication of a vacuum‐assisted Sankaranarayanan–Ramasamy (SR) method is reported by making modifications in the original SR setup for the growth of bulk single crystals with selective orientation at room temperature using volatile solvents. Utilizing this technique, the growth of bulk‐sized and technologically important single crystals, such as KDP, TGS, ADP, and benzophenone, is demonstrated. The powder XRD patterns of the grown crystals are obtained so as to confirm the growth plane of each crystal. UV–visible spectra show good transparency in the entire visible region for the grown crystals. The crystalline perfection of the grown crystals is analyzed using HRXRD. This handy and cost‐effective technique will pave the way for the growth of single crystals satisfying the requirements of the photonic industry.
Controls on gross production in an aspen–sagebrush vegetation mosaic
Authors: Fellows Aaron W. , Flerchinger Gerald N. , Seyfried Mark S. , Lohse Kathleen A. , Patton Nicholas R.
Published: September 2018

The critical zone (CZ; defined as the zone between the top of the vegetation canopy and the groundwater) mediates the impact of precipitation amount and timing on water availability and plant productivity. However, CZ structure, including soil and subsurface properties, are almost always unknown, leading to considerable uncertainty in the links between precipitation, plant water availability, and gross production. Using multiyear records of gross ecosystem CO2 exchange (GEE), micrometeorology, and streamflow, we examined the sensitivity of GEE to environmental controls in a sagebrush shrubland and an aspen forest. The sites were within 500 m of each other and had similar precipitation and temperature but marked differences in CZ structure. Cumulative growing season GEE was approximately two times greater at the aspen compared with the sagebrush, underscoring the importance of CZ properties in structuring spatial “hot spots” for carbon cycling. Larger soil water holding capacity and topography that produced lateral subsurface flow to the aspen enabled marked difference in plant functional type. Annual variability in growing season GEE within each site was not driven by annual precipitation; this lack of relationship was attributed to the CZ's limited ability to store water and an associated increase in water yield. Instead, both seasonal timing and cumulative growing season GEE for the sagebrush varied with spring and summer rain, whereas aspen GEE responded to spring snowpack conditions. These results emphasized how mapping and understanding CZ structure will help predict the spatial variability in plant functional type and temporal sensitivity of growing season GEE.
Eddy covariance based surface‐atmosphere exchange and crop coefficient determination in a mountainous peatland
Authors: Gerling Lars , Weber Tobias K.D. , Reineke Daniela , Durner Wolfgang , Martin Sabrina , Weber Stephan
Published: September 2018

In the soil–plant–atmosphere continuum, fluxes of water, energy, and carbon determine the water and carbon balance of peat bogs. We used eddy covariance (EC) measurements to study surface atmosphere exchange and its drivers above an ombrotrophic peat bog (Odersprungmoor) in the Harz Mountains, Germany, with nonideal measurement conditions during the growing season in 2013. For montane peatlands, only very few EC flux measurements exist due to site constraints, for example, surface slope, limited fetch, and frequent dew formation on open path sensors. The measured data were carefully filtered resulting in valid and representative fluxes for the bog. The evapotranspiration (ET) was further characterized by determining the adjusted crop coefficient (Kc*) for July and August and comparing it with Kc* values from 7 years of the FLUXNET site Mer Bleue bog, Ontario, Canada. While soil moisture was taken into consideration, the adjustment was nevertheless necessary as plant health and nutrient supply were not evaluated as required by FAO guidelines. Actual ET at OM was well described by the Kc* model (Kc* = 0.85, R2 = 0.85). The primary control on ET was available energy and atmospheric conditions and, marginally, the soil moisture conditions. This Kc* value is comparable to the calculated Kc* values for MB, which ranged between 0.82 and 0.86 (R2 between 0.84 and 0.97). Since these Kc* ranges are narrow for the different sites and years, we hypothesize that these values are good estimates for the true crop coefficients of Sphagnum‐dominated peat bogs.
Enhancing Aromatic Foldamer Helix Dynamics to Probe Interactions with Protein Surfaces
Authors: Vallade Maëlle , Sai Reddy Post , Fischer Lucile , Huc Ivan
Published: September 2018

Dynamic helices that undergo exchange between P and M conformations can be used as sensors when their interactions with chiral substances results in a helix handedness bias. For instance, chiral induction in short helically folded aromatic oligoamides based on 8‐amino‐2‐quinoline carboxylic acid (Q) has been used to detect interactions with proteins and nucleic acids. However, the stability of these helices in water increases rapidly with oligomer length to the extent that helix dynamics become too slow for sensing applications. We have developed an approach to enhance the helix dynamics of these oligomers through the introduction of more flexible 6‐aminomethyl‐2‐pyridinecarboxylic acid units (P) while preserving helix integrity. A series of P/Q hybrid oligoamides were synthesized and their rate of helix handedness inversion was evaluated by monitoring induced circular dichroism so as to define the requirements to bring kinetics in a practical range for sequences as long as fourteen units. Proof of principle was then brought by confining such sequences at the surface of carbonic anhydrase and showing that protein‐mediated helix handedness induction occurs.
Synthesis of Benzofuroquinolines via Phosphine‐Free Direct Arylation of 4‐Phenoxyquinolines in Air
Authors: Shanahan Rachel M. , Hickey Aobha , Reen F. Jerry , O'Gara Fergal , McGlacken Gerard P.
Published: September 2018

A palladium‐catalysed, phosphine‐free, direct arylation of 4‐phenoxyquinolines, in air is described. Using an intramolecular approach, the ring‐closed products are formed in yields of up to 95 %. This approach allows access to a range of benzofuroquinolines. An array of functional groups on both the quinoline and phenoxy rings are tolerated.
One‐Pot Synthesis of 6‐Aminopyrido[2,3‐d]pyrimidin‐7‐ones
Authors: Zinchenko Anna M. , Muzychka Lyubov V. , Kucher Olexandr V. , Sadkova Iryna V. , Mykhailiuk Pavel K. , Smolii Oleg B.
Published: September 2018

One‐pot synthesis of 6‐aminopyrido[2,3‐d]pyrimidin‐7‐ones from 4‐aminopyrimidine‐5‐carbaldehydes and the in situ N‐protected methyl glycinate is developed. The obtained compounds have a polyfunctional character and provide opportunities for their use in drug design projects.
A Glucose Selective Non‐enzymatic Potentiometric Chitosan‐Goldnanoparticle Nanocomposite Sensor Based on Boronic Acid‐Diol Recognition
Authors: Çelik Filiz , Çiftçi Hakan , Tamer Uğur
Published: September 2018

A new non‐enzymatic glucose sensor based gold nanoparticle (AuNp)‐chitosan (Ch/AuNp) was developed in this study. Gold nanoparticles were synthesized by using the green synthesis method, in which chitosan is used as both reducing and stabilizing agent. Gold nanoparticle surfaces were modified with different molecular agents (4‐mercaptophenyl boronic acid,MPB, and 1‐decanethiol,DT) being sensitive to glucose. Modified gold nanoparticles were immobilized to electrode surfaces and used for the glucose measurements by the potentiometric method. The best working conditions were determined for the glucose measurements. It was found that linear working range is 0.5–30 mM, while limit of detection is 0.3 mM for the glucose measurement of the prepared non‐enzymatic sensor. It was stated that the prepared sensor could be used at least 6 times and glucose response decreased approximately 10.97 % when it is waited for 30 days. Interference effect of some molecules for glucose measurement was investigated and usability of developed sensor was tested in human blood serum.
Stripe‐shaped Electrochemical Biosensor for Organophosphate Pesticide
Authors: Celebanska Anna , Jedraszko Justyna , Lesniewski Adam , Jubete Elena , Opallo Marcin
Published: September 2018

Detection of organophosphate pesticides is indispensable to improve the quality of the water and therefore required by the European Union law. Here, we propose a novel architecture of a pesticide biosensor where the enzyme and the electrode are placed into neighboring zones in the stripe form. This separation permits to use the optimal conditions for their immobilization resulting in undisrupted mechanical stability of the biosensor. The enzyme, acetylcholinesterase, generates thiocholine which is further oxidized at the carbon nanoparticles film electrode, exhibiting high electrocatalytic activity. The whole device was tested as a biosensor for malaoxon employing a wild or recombinant acetylcholinesterase. The latter allowed for incubation time decrease down to 10 minutes and lowered the detection limit to 0.25 nM. Moreover, the encapsulated enzyme activity was visualised by a scanning electrochemical microscopy.
Efficient Electrochemical Reduction of Oxygen Catalyzed by Porous Carbon Containing Trace Amount of Metal Residues
Authors: Feng Xin , Dong Xiaomei , Zhang Qingcheng , Cui Cuixia , Zhang JingJing , Chen Zhen , Wu Changmi , Jin Huile , Wang Shun , Wang Jichang
Published: September 2018

In this study carbon materials with a hierarchical pore structure have been fabricated through a scalable and template free solvothermal method in the presence of metal catalysts, where the presence of metal catalysts was found to be essential for the initial polymerization process. The as‐prepared carbon contained trace amounts of metal residues and exhibited highly efficient catalytic activity toward the oxygen reduction reaction (ORR). Among all the metal catalysts studied, cobalt containing porous carbon exhibited the highest ORR electrocatalytic activity with great tolerance to methanol crossover and excellent long‐term cycling stability, outperforming the commercial 30 % (w/w) Pt/C catalysts. The great performance may be contributed to the unique porous structure, the large specific surface area of cobalt‐doped carbon and chemical activity of cobalt. The result provides useful guidance for the development of carbon‐based electrocatalysts.
The Effect of Metal Components in the Quaternary Electrocatalysts on the Morphology and Catalytic Performance of Transition Metal Phosphides
Authors: Cao Qiao , Gu Wenling , Li Jing , Wang Erkang
Published: September 2018

Development of low‐cost, earth‐abundant alternative electrocatalysts to platinum catalyst for hydrogen evolution reaction (HER) is of great significance. Some multimetallic transition metal phosphides have been synthesized recently. However, the impacts of metal components on the morphology and performance of catalyst were less discussed. In this communication, taking the quaternary phosphides CoxNiyMnzP (x+y+z=1) grown on carbon cloth (CC) as an example, the influence of proportion of metals in catalysts on the morphology and HER performance was investigated in detail. The results indicated that When x/y/z=6/1/1(Co0.75Ni0.125Mn0.125P), a nanowire morphology was grown on CC with the optimal HER performance, which had a Tafel slope of 48.87 mV/dec and needed 137 and 190 mV to realize a current density of 10 and 100 mA cm−2, respectively. Moreover, the electrocatalysts exhibited an excellent long‐term electrochemical durability for at least 12.5 h.
Critical Effect of Film Thickness on Preconcentration Electroanalysis with Oriented Mesoporous Silica Modified Electrodes
Authors: Nasir Tauqir , Vodolazkaya Natalya A. , Herzog Grégoire , Walcarius Alain
Published: September 2018

Electrogenerated silica thin films exhibiting a regular hexagonal packing of vertically‐aligned mesopore channels are promising for preconcentration electroanalysis. This work demonstrates the critical role of film thickness on their sensing performance using paraquat as a model analyte, based on mesoporous silica films prepared by electrochemically assisted self‐assembly performed for various deposition times. Films prepared with too short synthesis times (<10 s) led to deposits covering partially the electrode surface and suffered from rather poor sensing performance. Then, uniformly deposited films were obtained (between 10 and 15 s), and sensitivity rose up by increasing deposition times, whereas some limitations started to occur with much thicker films (>15 s deposition times) as a result of less electrochemically accessible paraquat accumulated far away from the electrode surface and restricted mass transport through the whole film thickness. These limitations were also confirmed on the basis of multi‐layered mesoporous silica films, suggesting a behavior that might be typical for other types of film‐modified electrodes.
Identifying and confirming demotivating factors for village health workers in rural communities of Bhutan
Authors: Tshering Dolley , Tejativaddhana Phudit , Siripornpibul Taweesak , Cruickshank Mary , Briggs David
Published: September 2018

Background

Bhutan achieved over 95% of health coverage through its primary health care network and geared towards achieving and ensuring Universal Health Coverage. About 62.2% of the Bhutanese people are rural dwellers, living in villages. Village health workers (VHWs) are essential for primary health care delivery at the community level in order to bridge the gap between the health care system and the communities. However, increasing numbers of VHWs leaving the health care system remain a challenge for Bhutan. This study intends to find existing problems of motivation and retention among VHWs in Bhutan and to devise appropriate strategies for making effective policy interventions.

Methods

This quantitative study with a cross‐sectional survey design aims to determine demotivating factors. One stage cluster sampling technique was applied for VHWs from 12 districts in three regions. Data were collected by the trained enumerators using a pre‐tested semi‐structured questionnaire.

Results

The Confirmatory factor analysis identified and confirmed a four‐factor model of demotivation among VHWs in Bhutan. Among the four factors, the social factor was the main factor for VHWs leaving the health care system. However, the holistic combination of both financial and non‐financial motivator needs to be taken into consideration. The content analysis revealed six areas of recommendation for improving motivation and retention among VHWs.

Conclusion

The study concluded that managers and policymakers must give more emphasis to non‐financial motivators through the holistic approach to existing altruism and intrinsic needs.