bluuebunny/crossref_metadata_2025 huggingface dataset:
Dissociable age and memory relationships with hippocampal subfield volumes in vivo:Data from the Irish Longitudinal Study on Ageing (TILDA)
Authors: Carey Daniel , Nolan Hugh , Kenny Rose Anne , Meaney James
Published: July 2019

The heterogeneous specialisation of hippocampal subfields across memory functions has been widely shown in animal models. Yet, few in vivo studies in humans have explored correspondence between hippocampal subfield anatomy and memory performance in ageing. Here, we used a well-validated automated MR segmentation protocol to measure hippocampal subfield volumes in 436 non-demented adults aged 50+. We explored relationships between hippocampal subfield volume and verbal episodic memory, as indexed by word list recall at immediate presentation and following delay. In separate multilevel models for each task, we tested linearity and non-linearity of associations between recall performance and subfield volume. Fully-adjusted models revealed that immediate and delayed recall were both associated with cubic fits with respect to volume of subfields CA1, CA2/3, CA4, molecular layer, and granule cell layer of dentate gyrus; moreover, these effects were partly dissociable from quadratic age trends, observed for subiculum, molecular layer, hippocampal tail, and CA1. Furthermore, analyses of semantic fluency data revealed little evidence of robust associations with hippocampal subfield volumes. Our results show that specific hippocampal subfields manifest associations with memory encoding and retrieval performance in non-demented older adults; these effects are partly dissociable from age-related atrophy, and from retrieval of well-consolidated semantic categories.
Complex resistivity characteristics of saltwater-intruded sand contaminated by heavy metal
Authors: Nai Changxin , Sun Xiaochen , Wang Zeya , Xu Ya , Liu Yuqiang , Liu Jingcai , Dong Lu , Huang Qifei , Wang Yuling
Published: July 2019

Different pollutants affect electrical characteristics of soil, e.g., electric resistivity and capacity. The most extensively used non-intrusive methods in mapping these physical characteristics are electrical method. To better understand the effect of different hydrogeological and environmental process on resistivity and phase of complex resistivity under water-saturated soil, we carried out a controlled laboratory experiment where the host material was simulated by sand soil and the hydrogeological and environmental processes by groundwater table rise, seawater intrusion and heavy metal contamination. The experiment measured the resistivity and phase of soil saturated and unsaturated, with different pollutants added, together with their time-lapse change in a well-controlled column. With the involvement of more measurement parameters, complex resistivity method can provide more information than resistivity method, thereby having better performance in the detection and monitoring of changes in electrical properties of complex contaminated sites. For example, it is capable of discriminating the different contamination process, in this case, e.g., seawater intrusion and heavy metal contamination. In addition, it is still sensitive to the change of pollutant concentration even in site with high added concentration. Furthermore, simulating the saltwater-intruded site contaminated by manganese, it was found that the change of resistivity (ρ) can hardly be observed, while the responses of phase (φ) are so obvious that can be clearly observed.
Hyaluronan abrogates imatinib-induced senescence in chronic myeloid leukemia cell lines
Authors: Lompardía Silvina , Díaz Mariángeles , Pibuel Matías , Papademetrio Daniela , Poodts Daniela , Mihalez Cintia , Álvarez Élida , Hajos Silvia
Published: July 2019

Hyaluronan (HA) is the main glycosaminoglycan of the extracellular matrix. CD44 is the most important HA receptor, and both have been associated with poor prognosis in cancer. Chronic myeloid leukemia (CML) is characterized by the presence of a constitutively activated tyrosine kinase (Breakpoint Cluster Region - Abelson murine leukemia viral oncogene homolog1, BCR-ABL). It is mainly treated with BCR-ABL inhibitors, such as imatinib. However, the selection of resistant cells leads to treatment failure. The aim of this work was to determine the capacity of HA (high molecular weight) to counteract the effect of imatinib in human CML cell lines (K562 and Kv562). We demonstrated that imatinib decreased HA levels and the surface expression of CD44 in both cell lines. Furthermore, HA abrogated the anti-proliferative and pro-senescent effect of Imatinib without modifying the imatinib-induced apoptosis. Moreover, the inhibition of HA synthesis with 4-methylumbelliferone enhanced the anti-proliferative effect of imatinib. These results suggest that Imatinib-induced senescence would depend on the reduction in HA levels, describing, for the first time, the role of HA in the development of resistance to imatinib. These findings show that low levels of HA are crucial for an effective therapy with imatinib in CML.
Osteoporosis Recognition in Rats under Low-Power Lens Based on Convexity Optimization Feature Fusion
Authors: Cai Jie , He Wen-guang , Wang Long , Zhou Ke , Wu Tian-xiu
Published: July 2019

Considering the poor medical conditions in some regions of China, this paper attempts to develop a simple and easy way to extract and process the bone features of blurry medical images and improve the diagnosis accuracy of osteoporosis as much as possible. After reviewing the previous studies on osteoporosis, especially those focusing on texture analysis, a convexity optimization model was proposed based on intra-class dispersion, which combines texture features and shape features. Experimental results show that the proposed model boasts a larger application scope than Lasso, a popular feature selection method that only supports generalized linear models. The research findings ensure the accuracy of osteoporosis diagnosis and enjoy good potentials for clinical application.
A new regulatory mechanism for Raf kinase activation, retinoic acid-bound Crabp1
Authors: Park Sung Wook , Nhieu Jennifer , Persaud Shawna D. , Miller Michelle C. , Xia Youlin , Lin Yi-Wei , Lin Yu-Lung , Kagechika Hiroyuki , Mayo Kevin H. , Wei Li-Na
Published: July 2019

The rapidly accelerated fibrosarcoma (Raf) kinase is canonically activated by growth factors that regulate multiple cellular processes. In this kinase cascade Raf activation ultimately results in extracellular regulated kinase 1/2 (Erk1/2) activation, which requires Ras binding to the Ras binding domain (RBD) of Raf. We recently reported that all-trans retinoic acid (atRA) rapidly (within minutes) activates Erk1/2 to modulate cell cycle progression in stem cells, which is mediated by cellular retinoic acid binding protein 1 (Crabp1). But how atRA-bound Crabp1 regulated Erk1/2 activity remained unclear. We now report Raf kinase as the direct target of atRA-Crabp1. Molecularly, Crabp1 acts as a novel atRA-inducible scaffold protein for Raf/Mek/Erk in cells without growth factor stimulation. However, Crabp1 can also compete with Ras for direct interaction with the RBD of Raf, thereby negatively modulating growth factor-stimulated Raf activation, which can be enhanced by atRA binding to Crabp1. NMR heteronuclear single quantum coherence (HSQC) analyses reveal the 6-strand β-sheet face of Crabp1 as its Raf-interaction surface. We identify a new atRA-mimicking and Crabp1-selective compound, C3, that can also elicit such an activity. This study uncovers a new signal crosstalk between endocrine (atRA-Crabp1) and growth factor (Ras-Raf) pathways, providing evidence for atRA-Crabp1 as a novel modulator of cell growth. The study also suggests a new therapeutic strategy by employing Crabp1-selective compounds to dampen growth factor stimulation while circumventing RAR-mediated retinoid toxicity.
Tumor intrinsic immunity related proteins may be novel tumor suppressors in some types of cancer
Authors: Xiong Donghai , Wang Yian , You Ming
Published: July 2019

Immune checkpoint blockade therapy (ICBT) can unleash T-cell responses against cancer. However, only a small fraction of patients exhibited responses to ICBT. The role of immune checkpoints in cancer cells is not well understood. In this study, we analyzed T-cell coinhibitory/costimulatory genes across more than 1100 samples of the Cancer Cell Line Encyclopedia (CCLE). Nearly 90% of such genes were not expressed or had low expression across the CCLE cancer cell lines. Cell line screening showed the enrichment of cancer cells deprived of the expression ofCD27,CEACAM1,CTLA4,LRIG1,PDCD1LG2, orTNFRSF18, suggesting their role as tumor suppressor. The metagene expression signature derived from these six genes - Immu6Metagene was associated with prolonged survival phenotypes. A common set of five oncogenic pathways were significantly inhibited in different types of tumors of the cancer patients with good survival outcome and high Immu6Metagene signature expression. These pathways were TGF-β signaling, angiogenesis, EMT, hypoxia and mitotic process. Our study showed that oncoimmunology related molecules especially the six genes of the Immu6Metagene signature may play the tumor suppressor role in certain cancers. Therefore, the ICBT targeting them should be considered in such context to improve the efficacy.
Mitochondrial DNA sequencing reveals association of variants and haplogroup M33a2′3 with High altitude pulmonary edema susceptibility in Indian male lowlanders
Authors: Sharma Swati , Singh Sayar , Gupta Rajinder K. , Ganju Lilly , Singh Shashi Bala , Kumar Bhuvnesh , Singh Yamini
Published: July 2019

High Altitude Pulmonary Edema (HAPE) is a threatening disorder caused due to acute exposure to high altitude above 3000 m. Apart from multiple factors involved, the genetic factors also play an important function in the pathogenesis of HAPE. This study aims to evaluate the role of mtDNA polymorphism and their association with haplogroup in understanding the etiology of HAPE. In this study, all the HAPE susceptible and acclimatized control subjects could be classified into nine haplogroups pertaining mostly to Macrohaplogroup M and U. The frequency of haplogroup M was significantly higher in HAPE susceptibles whereas the haplogroup M33a2′3 was found only in HAPE susceptibles. The variant G4491A and A4944G of MT-ND2, A14002G of MT-ND5, and C8562T of MT-ATP8, were definition site of haplogroup M33a2′3. The frequency of A10398G of MT-ND3, A8701G of MT-ATP6 and C14766T of MT-CYB genes were significantly higher in HAPE susceptibles. mtDNA copy number also plays a significant synergistic role in HAPE susceptibility. Our findings suggests that variants in MT-ND2 and MT-ND5 were predicted to confer decreased protein stability in HAPE susceptibles and in particular, highly conserved variants G4491A, A4944G and A14002G associated with haplogroup M33a2′3 may be the primary cause of susceptibility to HAPE in Indian male lowlanders.
Role of procalcitonin as a predictor in difficult laparoscopic cholecystectomy for acute cholecystitis case: A retrospective study based on the TG18 criteria
Authors: Wu Tianchong , Luo Minjun , Guo Yuehua , Bi Jiangang , Guo Yusheng , Bao Shiyun
Published: July 2019

Difficult laparoscopic cholecystectomy (DLC) is difficult to precisely predict before operation. This observational cohort study aimed to evaluate the predictive value of procalcitonin (PCT) for DLC in patients with acute cholecystitis (AC). A total of 115 patients were included in the study from January 2017 to April 2018. Multiple logistic regression and receiver-operating characteristic (ROC) were performed to evaluate the predictive value of PCT levels in DLC. Patients with DLC had significantly higher Tokyo Guidelines 2018 (TG18) grade (P = 0.002) and levels of C-reactive protein (CRP) (P = 0.007) and PCT (P < 0.001). The cut-off value of PCT for predicting DLC was 1.50 ng/ml. The sensitivity and specificity were 91.3% (95% CI 78.3–97.1) and 76.8% (95% CI 64.8–85.8), respectively. The area under ROC curve was 92.7% (95% CI 88.2–97.3, P < 0.001). Our results suggested that PCT was a good predictor for DLC in the AC patients, but further research is necessary. Monitoring of PCT trends in AC patients may be useful for preoperative risk assessment.
Rubber-state NMR Spectroscopy
Authors: Kawahara Seiichi , Yamamoto Yoshimasa , Saito Takayuki
Published: July 2019

Vulcanized rubbers, i.e., vulcanized natural rubber and vulcanized chloroprene rubber, were characterized by rubber-state NMR spectroscopy. High resolution 1H and 13C-NMR spectra were accomplished for the vulcanized rubbers due to fast magic angle spinning. The correlation between 1H and 13C of the vulcanized rubbers was investigated by one- and two-dimensional measurements. As for vulcanized natural rubber, the signals, appearing between 40 and 60 ppm, were well assigned by rubber-state NMR spectroscopy; for instance, the signal at 40 ppm was assigned to C1 of trans-1,4-isoprene units, while the signal at 44 ppm was assigned to secondary carbons linking to an S atom and signals at 58 ppm were assigned to tertiary and quaternary carbons linking to S atoms. In contrast, for chloroprene rubber, a 1H-signal at 0.9 ppm, appearing after vulcanization, was correlated to a 13C-signal at 14.5 ppm and the 1H signal at 1.3 ppm was correlated to a 13C-signal at 22.5, 29.5, and 31.8 ppm. A constitutional unit, i.e., CH3–CH2–CH2–S–R was found for vulcanized chloroprene rubber by rubber-state NMR spectroscopy.
Chain Proximity of Polystyrene in Bulk Polymer, Polymer Blend and Nanocomposites
Authors: Wang Xiaoliang
Published: July 2019

Chain proximity in polymer glasses was investigated by a new strategy combining preparation of a 2H enriched polymer blend with analysis by 1H dipolar filtered solid-state NMR under fast magic angle spinning (MAS). Fast MAS at 25 kHz induces crucial changes in spin dynamics and selectively isolates the proton signals of hydrogenous polymer chains in which protons are sufficiently close to the 2H nuclei of deuterated polymer chains. The present NMR method is robust for characterizing the chain interpenetration in bulk polymer glasses, e.g., hydrogenated polystyrene (PS-H)/deuterated polystyrene (PS-D) blends, and chain compatibility in polymer blends, e.g., PS-D/hydrogenated poly(2,6-dimethyl-1,4-phenylene oxide) (PPO), even though the chemical shifts are completely undistinguishable for the two components, which is extremely challenging for traditional NMR techniques. In polymer/inorganic nanoparticle nanocomposites, the chain proximity could be explored by 1H dipolar filtered solid-state NMR under fast MAS, on the basis of the dynamics difference generated by the inorganic interface. The understanding of chain proximity at a short length scale of 0.5 nm provides us better insights into achieving better performance of polymer materials.
Applications of Solid-state NMR in Crystalline Solid Polymer Electrolytes
Authors: Fu Xiaobin , Chen Qun , Yao Ye-Feng
Published: July 2019

Recent progress in solid-state NMR studies on the structure and dynamics of solid crystalline polymer electrolytes has been reviewed in this chapter. The content of the chapter is arranged as follows: firstly, the background knowledge about solid-state polymer electrolyte (SPE) materials is introduced briefly. Secondly, we will review the solid-state 13C NMR studies on the structure and dynamics of the crystalline PEO/Li+ complex SPEs, focusing on the helical jump motions of the chain segments in the complex crystal. Afterwards, 2H/1H NMR studies on cyclodextrin-PEOn/Li+ (CD-PEOn/Li+) complex crystalline SPEs are discussed, demonstrating how the complicated structure and dynamics of the PEO chains in these crystalline SPE systems can be well tackled by well-designed solid-state NMR techniques. In the final part of this chapter, the application of 7Li NMR on crystalline SPEs is reviewed. We intend to demonstrate that advanced NMR combined with other analytical techniques now can provide very detailed knowledge about the structure and dynamics of solid crystalline polymer electrolyte systems.
Mesoporous graphitic carbon nitride@NiCo2O4 nanocomposite as a solid phase microextraction coating for sensitive determination of environmental pollutants in human serum samples
Authors: Zhang Jing , Li Wenqi , Zhu Wenli , Qin Peige , Lu Minghua , Zhang Xuebin , Miao Yuchen , Cai Zongwei
Published: July 2019

Mesoporous graphitic carbon nitride (MCN)@NiCo2O4 was prepared and used as an SPME coating for high efficiency extraction of trace environmental pollutants.
Drug–drug salts of mefenamic acid\tolfenamic acid and piperazine to improve physicochemical properties for potential veterinary use
Authors: Wang Xinyi , Xu Shijie , Jia Lina , Yang Yujia , Liu Yu , Gong Junbo , Wu Songgu
Published: July 2019

Drug–drug salts of mefenamic acid\tolfenamic acid and piperazine were designed to improve the solubility and hygroscopicity, which could possibly extend the drug–drug salt form into veterinary use.
Unoccupied electronic band structure of pentagonal Si nanoribbons on Ag(110)
Authors: Kleimeier Nils Fabian , Wenzel Gabi , Urban Adrian Joe , Tchalala Mohamed Rachid , Oughaddou Hamid , Dedkov Yuriy , Voloshina Elena , Zacharias Helmut
Published: July 2019

The unoccupied band structure of silicon nanoribbons on Ag(110) was investigated using k-resolved inverse photoemission spectroscopy and DFT calculations.
Role of conductive binder to direct solid–electrolyte interphase formation over silicon anodes
Authors: Browning Katie L. , Browning James F. , Doucet Mathieu , Yamada Norifumi L. , Liu Gao , Veith Gabriel M.
Published: July 2019

With the use of in situ neutron reflectometry (NR) we show how the addition of an electronically conductive polymeric binder, PEFM, mediates the solid–electrolyte interphase (SEI) formation and composition on an amorphous Si (a-Si) electrode as a function of the state-of-charge.
The addition of methanol to Criegee intermediates
Authors: Aroeira Gustavo J. R. , Abbott Adam S. , Elliott Sarah N. , Turney Justin M. , Schaefer Henry F.
Published: July 2019

High level ab initio methods are employed to study the addition of methanol to the simplest Criegee intermediates and its methylated analogue. Kinetic rate constants over a range of temperatures are computed and compared to experimental results.
Effect of interfacial recombination, bulk recombination and carrier mobility on the J–V hysteresis behaviors of perovskite solar cells: a drift-diffusion simulation study
Authors: Xiang Jin , Li Yana , Huang Feng , Zhong Dingyong
Published: July 2019

A J–V hysteresis loop with a large gap near the VOC (or JSC) region appears by interfacial recombination (or bulk recombination).
Assessment of heteronuclear long-lived states at ultralow magnetic fields
Authors: Zhukov Ivan V. , Kiryutin Alexey S. , Yurkovskaya Alexandra V. , Ivanov Konstantin L.
Published: July 2019

A study of long-lived spin states in hetero-nuclear spin systems is presented.
Synthesis, structural properties and reactivity of ruthenocene-based pincer Pd(ii) tetrahydroborate
Authors: Safronov Sergey V. , Gutsul Evgenii I. , Golub Igor E. , Dolgushin Fedor M. , Nelubina Yulia V. , Filippov Oleg A. , Epstein Lina M. , Peregudov Alexander S. , Belkova Natalia V. , Shubina Elena S.
Published: July 2019

Non-covalent interactions determine the structure, crystal packing and reactivity of isolated ruthenocene-based pincer Pd(ii) complexes. Bifurcate dihydrogen-bonded complexes are active intermediates of tetrahydroborate alcoholysis.
A sustainable biochar catalyst synergized with copper heteroatoms and CO2 for singlet oxygenation and electron transfer routes
Authors: Wan Zhonghao , Sun Yuqing , Tsang Daniel C. W. , Yu Iris K. M. , Fan Jiajun , Clark James H. , Zhou Yaoyu , Cao Xinde , Gao Bin , Ok Yong Sik
Published: July 2019

Engineered biochar synergized from copper heteroatoms and CO2 fosters non-radical persulfate activation for sustainable remediation.
A naphthalimide-indole fused chromophore-based fluorescent probe for the detection of biothiol with red emission and a large Stokes shift
Authors: Rong Yifan , Wang Chen , Chuai Panfeng , Song Yunfan , Zhou Shuang , Hou Peng , Liu Xingjiang , Wei Liuhe , Song Xiangzhi
Published: July 2019

This probe exhibited red emission (λmax = 590 nm) and a large Stokes shift (143 nm) for the detection of biothiols.
Controllable digital resistive switching for artificial synapses and pavlovian learning algorithm
Authors: Kumar Mohit , Abbas Sohail , Lee Jung-Ho , Kim Joondong
Published: July 2019

Synaptic response has been enhanced by 340 times by geometrical modulation of a ZnO-based memristor. The device showed a variety of comprehensive synaptic functions, including the Pavlovian associative learning process in the human brain.
Tailoring the shape and size of wet-chemical synthesized FePt nanoparticles by controlling nucleation and growth with a high magnetic field
Authors: Wu Chun , Wang Xiaoyang , Pei Wenli , Zhao Dong , Wang Kai , Li Guojian , Wang Qiang
Published: July 2019

A 6 Tesla high magnetic field (HMF) was separately introduced into the nucleation stage and growth stage and into both stages during the wet-chemical synthesis of FePt nanoparticles.
Rational design and facile fabrication of biocompatible triple responsive dendrimeric nanocages for targeted drug delivery
Authors: Zhong Dan , Wu Huayu , Wu Yahui , Li Yunkun , Xu Xianghui , Yang Jun , Gu Zhongwei
Published: July 2019

We developed a biocompatible triple-responsive dendrimeric nanocage (TDN) through a simple method for targeted drug delivery.
Dynamic optical activity induction in theN-alkyl-N′-trityl ureas and thioureas
Authors: Prusinowska Natalia , Czapik Agnieszka , Wojciechowska Martika , Kwit Marcin
Published: July 2019

Stereodynamic trityl group, utilized as a reporter of chirality, hampers hydrogen bonding network in optically active urea and thiourea derivatives.
Visible-light-mediated difunctionalization of vinylcyclopropanes for the synthesis of 1-sulfonylmethyl-3,4-dihydronaphthalenes
Authors: Wang Qiao-Lin , Zhang Wen-Zheng , Zhou Quan , Zhou Cong-Shan , Xiong Bi-Quan , Tang Ke-Wen , Liu Yu
Published: July 2019

An efficient method for the visible-light-mediated sulfonylation/arylation of the C–C σ-bond in vinylcyclopropanes with sulfonyl chlorides to synthesize 1-sulfonylmethyl-substituted 3,4-dihydronaphalenes has been developed.
Mild C–H functionalization of alkanes catalyzed by bioinspired copper(ii) cores
Authors: Kirillova Marina V. , Fernandes Tiago A. , André Vânia , Kirillov Alexander M.
Published: July 2019

Three new copper(ii) coordination compounds with aminoalcohol and carboxylate type ligands were self-assembled, fully characterized, and applied as efficient homogeneous catalysts for the mild oxidation and carboxylation of saturated hydrocarbons.
Correction: (E)-Selective Friedel–Crafts acylation of alkynes to β-chlorovinyl ketones: defying isomerizations in batch reactions by flow chemistry approaches
Authors: Koo Hyungmo , Young Kim Hun , Oh Kyungsoo
Published: July 2019

Correction for ‘(E)-Selective Friedel–Crafts acylation of alkynes to β-chlorovinyl ketones: defying isomerizations in batch reactions by flow chemistry approaches’ by Hyungmo Koo et al., Org. Chem. Front., 2019, 6, 1868–1872.
Correction: Effects of water, ammonia and formic acid on HO2 + Cl reactions under atmospheric conditions: competition between a stepwise route and one elementary step
Authors: Zhang Tianlei , Zhang Yongqi , Wen Mingjie , Tang Zhuo , Long Bo , Yu Xiaohu , Zhao Caibin , Wang Wenliang
Published: July 2019

Correction for ‘Effects of water, ammonia and formic acid on HO2 + Cl reactions under atmospheric conditions: competition between a stepwise route and one elementary step’ by Tianlei Zhang et al., RSC Adv., 2019, 9, 21544–21556.
An examination of pre-service chemistry teachers’ meaningful understanding and learning difficulties about aromatic compounds using a systemic assessment questions diagram
Authors: Sendur Gulten
Published: July 2019

In order for students to reach a level of meaningful understanding of chemistry, it is vital that they are able to form accurate relationships between different concepts. In particular, in organic chemistry, identifying intermolecular reactions, considering these reactions as a whole, and defining their results will make important contributions to attaining meaningful understanding. This study aims to explore how pre-service chemistry teachers identify aromatic compound reactions and form associations between them and to discover what kinds of learning difficulties they encounter in forming these associations. In this context, the study, conducted as phenomenographical research, was carried out at a faculty of education in Turkey with 15 pre-service teachers enrolled in the Department of Chemistry Education who had taken the Organic Chemistry 1 and 2 courses. Selected on the basis of purposive sampling, the pre-service chemistry teachers were first asked systemic assessment questions (SAQs) related to aromatic compound reactions. In these questions, the pre-service chemistry teachers were asked to identify 7 molecules in the class of aromatic compounds and complete a diagram by taking into consideration synthesis and reaction conditions. The pre-service chemistry teachers were also asked to indicate two reactions that were not included in the SAQs diagram, together with their reagents and conditions. After completing their responses to the SAQs diagram, individual interviews were held with each of the pre-service chemistry teachers using the think-aloud technique. The research revealed at the end of the quantitative analysis of the data obtained from the SAQs diagram that most of the pre-service chemistry teachers achieved moderate-level scores. At the same time, the qualitative analysis of the data obtained from the SAQs diagram and from the interviews showed that the pre-service chemistry teachers were more successful in identifying and forming associations with the reactions of “nitration” and “sulfonation of aromatic compounds” but had difficulty with the “Friedel–Crafts alkylation,” “oxidation” and “reduction” reactions and with the “bromination of alkenylbenzenes” and the “addition reaction of the double bond of alkenylbenzenes.” Another important finding resulting from this study was that only a few pre-service chemistry teachers were able to identify a new reaction on the SAQs diagram. All of these findings indicate that the pre-service teachers are not very equipped to form meaningful relationships in the context of aromatic compounds, which is one of the basic topics of organic chemistry.
Helical supramolecular polymer nanotubes with wide lumen for glucose transport: towards the development of functional membrane-spanning channels
Authors: Zhang Chenyang , Deng Xiaoli , Wang Chenxi , Bao Chunyan , Yang Bing , Zhang Houyu , Qi Shuaiwei , Dong Zeyuan
Published: July 2019

Helical supramolecular polymers with a wide lumen structure can puncture the lipid bilayer membrane to facilitate the transport of glucose.
Drop/bubble transportation and controllable manipulation on patterned slippery lubricant infused surfaces with tunable wettability
Authors: Li Qi , Wu Daheng , Guo Zhiguang
Published: July 2019

A patterned slippery film with reversible wettability was prepared successfully for directional transportation and manipulation of droplets and bubbles.
Laparoendoscopic single-site nephrectomy versus conventional laparoendoscopic nephrectomy for kidney tumor: a systematic review and meta-analysis
Authors: Feng Dengyuan , Cong Rong , Cheng Hong , Wang Yi , Zhou Jiajun , Xia Jiadong , Gu Min
Published: July 2019

With the increasing application of laparoendoscopic single-site nephrectomy (LESS-N) in kidney tumor, accumulating studies compared it with conventional laparoendoscopic nephrectomy (CL-N). However, controversial outcomes were reported. Hence, this meta-analysis was carried out to clarify these issues. Online databases PubMed, EMBASE and the Cochrane Library were searched comprehensively for eligible studies published before 24 July 2018. Odds ratios (ORs) or standardized mean differences (SMDs) with corresponding 95% confidence intervals (CIs) were collected for evaluating the pooled results of relevant outcomes. Ultimately, 13 eligible articles were enrolled. Meanwhile, compared with CL-N, LESS-N was related to a longer operation time (SMD: 0.40; 95% CI, 0.23–0.58; P=0.000), a shorter length of hospital stay (LOS) (SMD: −0.32; 95% CI, −0.62 to −0.02; P=0.034), a lower visual analog scale (VAS) score (SMD: −0.89; 95% CI, −1.22 to −0.56; P=0.000) and a lower analgesic requirement (SMD: −0.55; 95% CI, −0.87 to −0.23; P=0.001). There was no statistical difference in the postoperative day of oral intake, estimated blood loss (EBL), conversion rate, perioperative complications, intraoperative complications, postoperative complications, minor complications and major complications between LESS-N and CL-N. Patients with LESS-N for kidney tumor could have a longer operation time and shorter LOS, and meanwhile could need less analgesics and suffer less pain after LESS-N.
MiR-216a-5p-containing exosomes suppress rTp17-induced inflammatory response by targeting TLR4
Authors: Peng Rui-Rui , Shang Shu-Xian , Zhao Li-Shi , Long Fu-Quan
Published: July 2019

Syphilis caused by Treponema pallidum (T. pallidum) infection is accompanied by inflammatory injury of tissue, and has a worldwide distribution and increasing incidence over the past decade. Tp17 has been reported to be a strong membrane immunogen, and was initially observed to play a role in inflammation during syphilis, reacting intensely with human syphilitic sera. We therefore used recombinant Tp17 (rTp17) as a stimulator in our study. Increasing evidence has demonstrated that microRNA (miRNA)-containing exosomes have emerged as a potential effective therapeutic target for many diseases. However, the biological functions and molecular mechanisms of miR-216a-5p in syphilis pathogenesis remain unknown. Our study first identified dramatically decreased miR-216a-5p in plasma of syphilis patients compared with the healthy control, which was negatively correlated with the expression of inflammatory cytokines, including IL-1β, IL-6, and TNF-α. Moreover, endothelial cells treated with miR-216a-5p-containing exosomes significantly attenuated the rTp17-induced inflammatory response. More importantly, we identified that miR-216a-5p could bind to the 3′-untranslated region (UTR) of Toll-like receptor (TLR) 4 (TLR4), and overexpression of TLR4 largely rescued the miR-216a-5p-mediated suppression of rTp17-induced inflammatory cytokine production and the TLR4-MYD88 signaling pathway. Thus, our results reveal a novel role of miR-216a-5p-containing exosomes in endothelial cells, implying a potential therapeutic target for inflammation in syphilis patients.
FIRTEZ-dz
Authors: Pastor Yabar A. , Borrero J. M. , Ruiz Cobo B.
Published: July 2019

We present a numerical code that solves the forward and inverse problem of the polarized radiative transfer equation in geometrical scale under the Zeeman regime. The code is fully parallelized, making it able to easily handle large observational and simulated datasets. We checked the reliability of the forward and inverse modules through different examples. In particular, we show that even when properly inferring various physical parameters (temperature, magnetic field components, and line-of-sight velocity) in optical depth, their reliability in height-scale depends on the accuracy with which the gas-pressure or density are known. The code is made publicly available as a tool to solve the radiative transfer equation and perform the inverse solution treating each pixel independently. An important feature of this code, that will be exploited in the future, is that working in geometrical-scale allows for the direct calculation of spatial derivatives, which are usually required in order to estimate the gas pressure and/or density via the momentum equation in a three-dimensional volume, in particular the three-dimensional Lorenz force.
Multiply-periodic hypersurfaces with constant nonlocal mean curvature
Authors: Minlend Ignace Aristide , Niang Alassane , Thiam El hadji Abdoulaye
Published: July 2019

We study hypersurfaces with fractional mean curvature inN-dimensional Euclidean space. These hypersurfaces are critical points of the fractional perimeter under a volume constraint. We use local inversion arguments to prove existence of smooth branches of multiply-periodic hypersurfaces bifurcating from suitable parallel hyperplanes.
A numerical model of electrical characteristics for the monolayer graphene field effect transistors
Authors: Xiao Xiang-Jie , Xu Piao-Rong , Liu Gen-Hua , Zhou Hui-Ying , Li Jian-Jun , Chen Ai-Bin , Zhang Yong-Zhong , Huang Hong-Xu
Published: July 2019

A numerical model of carrier saturation velocity and drain current for the monolayer graphene field effect transistors (GFETs) is proposed by considering the exponential distribution of potential fluctuations in disordered graphene system. The carrier saturation velocity of GFET is investigated by the two-region model, and it is found to be affected not only by the carrier density, but also by the graphene disorder. The numerical solutions of the carrier density and carrier saturation velocity in the disordered GFETs yield clear and physical-based results. The simulated results of the drain current model show good consistency with the reported experimental data.
Effects of vapor injection modes on the heating performance of heat pumps
Authors: Liu Bin , Chai Lin , Chen Aiqiang , Tang Fuhui , Sefiane Khellil , Achkar Georges E.I.
Published: July 2019

Heat pumps are widely investigated for their versatile use in a wide range of applications. In this study, three types of heat pumps were experimentally compared. These heat pumps include an one-stage without injection vapor heat pump, an one-stage injection vapor heat hump and a two-stage injection vapor heat pump with an economizer. The results showed that the heating capacity of all three variants of heat pumps decreases with the decrease of the evaporation temperature. However, the attenuation ratio of the heating capacity is found to be different from one pump to another. On the one hand, the largest attenuation rate is found to be 68.84% for evaporating temperatures ranging from −1 °C to −23 °C and for the case of one-stage heat pump. On the other hand, the smallest attenuation rate is found to be 31% for the two-stage injection vapor heat pump in the same temperature range. It is worth noting that the heating efficiency is improved by the amount of vapor injection, nevertheless, there is a maximum value due to the limitations of the economizer. The two-stage injection vapor heat pump can exhibit an enhanced heating efficiency of 127% compared to the one-stage without injection vapor heat pump and 13% compared to the one-stage injection vapor heat pump for an evaporating temperature of −23 °C.
Bedeutung des Prozessreifegrads für die Patientenorientierung im Gesundheitswesen
Authors: Bogodistov Yevgen , Moormann Jürgen , Sibbel Rainer , Krupskyi Oleksandr , von Hanstein Moritz , Grytsenko Stanyslav
Published: July 2019

Zielsetzung Eine gute Organisation der internen Prozesse ist für ein funktionierendes Gesundheitswesen essenziell. Von besonderer Bedeutung ist der Prozess der Behandlung und Interaktion mit den Patienten, da die Wahrnehmung von Behandlung und Interaktion in einem direkten Zusammenhang mit der Patientenzufriedenheit steht. Letztere hat einen großen Einfluss auf die Gesundung der Patienten. Welche Auswirkungen der Reifegrad des Behandlungs- und Interaktionsprozesses auf die Patientenorientierung hat, wird am Beispiel einer umfangreichen Befragung von Krankenhausmanagern in der Ukraine untersucht.

Methodik Die Analyse basiert auf einer empirischen Erhebung, die bei Chefärzten und deren Stellvertretern in einer ukrainischen Großstadt, die als Modell-Stadt einer umfassenden Gesundheitsreform fungiert, durchgeführt wurde. Anhand des Business Process Maturity Model (BPMM) haben wir unsere Hypothese, dass ein hoher Prozessreifegrad zu einem hohen Maß an Patientenorientierung führt, getestet. Dazu haben wir eine Methode zur Messung des Prozessreifegrads entwickelt und diese auf Validität und Reliabilität geprüft. An der Befragung haben 79 Chefärzte und Stellvertreter teilgenommen, die alle öffentlichen Gesundheitseinrichtungen der Stadt (Krankenhäuser, Familienärztehäuser etc.) repräsentieren.

Ergebnisse Die Untersuchung zeigt einen klaren Zusammenhang zwischen der Reife des Behandlungs- und Interaktionsprozesses und dem Grad der Patientenorientierung der jeweiligen Gesundheitseinrichtung. Die Varianz, die durch die unabhängige Variable Prozessreifegrad erklärt wird, liegt bei 16,3 %. Alle formativen Dimensionen zeigen einen stark signifikanten Einfluss auf das Konstrukt „Patientenorientierung”. Der Reifegrad des Behandlungs- und Interaktionsprozesses weist ebenfalls einen stark signifikanten Einfluss auf die Patientenorientierung auf.

Schlussfolgerung Für Gesundheitseinrichtungen ist es von großer Bedeutung, einen hohen Reifegrad des Behandlungs- und Interaktionsprozesses zu erreichen, um damit dem Anspruch von Patientenorientierung gerecht werden zu können. Die Reife des Prozesses kann mit dem im Rahmen dieser Studie entwickelten Fragebogen getestet werden.
Current Status of Expiry of Homeopathic Medicines in Brazil, Germany, India and the United States: A Critical Review
Authors: Valavan Ramachandran , Cesar Amarilys
Published: July 2019

Background Assignment of expiry date to homeopathic medicines is a subject of important concern to its pharmacists and practitioners. This study compares the regulatory framework for the expiry of homeopathic medicines in four countries: Brazil, Germany, India and the United States.

Findings Different or no expiry periods are variously followed. Whereas Germany, with some exceptions, employs a maximum expiry of 5 years for both potencies and finished products, Brazil adopts a 5-year expiry for finished products only, potencies used in manufacture being exempted from an assigned expiry date. In India, all homeopathic medicines except dilutions and back potencies have a maximum of 5 years' shelf-life, including those supplied to consumers. In the United States, homeopathic medicines are exempted from expiry dates.

Comments There is neither a rational basis nor scientific evidence for assigning a short (3–5 years) expiry period for homeopathic medicines as followed in some of the countries, particularly in light of the fact that some studies have shown homeopathic medications to be effective even after 25 years. Homeopathic ultra-dilutions seem to contain non-material activity that is maintained over time and, since these exhibit different chemical properties compared to the original starting material, it is quite possible they possess properties of longer activity than conventional medicines. Regulators should acknowledge this feature and differentiate expiry of homeopathic medicinal products from that of conventional drugs.
Postoperative Complications Causing Readmission in 30 Days after Total Knee Arthroplasty: A Retrospective Nested Case-Control Study of Risk Factors Based on Propensity Score Matching
Authors: Tang Haozheng , Li Hui , Zhang Shutao , Wang You , Qu Xinhua , Yue Bing
Published: July 2019

We performed this study to identify independent risk factors for life-threatening postoperative complications causing 30-day readmissions after total knee arthroplasty (TKA). Improved understanding of these risks may improve efficiency and safety of treatment. We performed a retrospective, nested case-control study using an open-access database of 2,622 patients who underwent primary TKA at a tertiary academic medical center in Singapore between January 2013 and June 2014. Patients were grouped according to the incidence of complications. Multivariate logistic analysis was performed to identify predictive factors for TKA complications. The incidence of postoperative complications was 1.72%. Compared with cases performed with an operative time < 70 minutes, increased operative time was associated with a higher risk of complications. Case duration > 90 minutes was associated with an increased risk (adjusted odds ratio [aOR] = 4.57, p = 0.001; case duration ≥ 111 minutes, aOR = 4.64, p = 0.04; and case duration between 91 and 110 minutes, aOR = 3.20, p = 0.03). The correlation between operative time and complications was nonlinear. Cerebrovascular accident (CVA) or transient ischemic attack (TIA) was an independent risk factor for increased complication rate (aOR = 11.59, p = 0.02). Operative duration has been identified as an independent risk factor for complications after TKA. As it remains a modifiable factor to which doctors are interested in bringing quality improvement, the risk of postoperative complications will be reduced by minimizing the operative duration.
Exploration of the Vaginal and Gut Microbiome in African American Women by Body Mass Index, Class of Obesity, and Gestational Weight Gain: A Pilot Study
Authors: Faucher Mary Ann , Greathouse Kristen Leigh , Hastings-Tolsma Marie , Padgett Robert Noah , Sakovich Kimberly , Choudhury Ankan , Sheikh Aadil , Ajami Nadim J. , Petrosino Joseph F.
Published: July 2019

Objective This study determines the differences in the distal gut and vaginal microbiome in African American (AA) women by prepregnancy body mass index and gestational weight gain (GWG) comparing women with and without obesity and by obesity class.

Study Design We prospectively sampled the vaginal and distal gut microbiome in pregnant AA women at two time points during pregnancy. Samples were analyzed using high-throughput sequencing of the V4 region of the 16S ribosomal ribonucleic acid gene.

Results Distinct differences in vaginal and distal gut α-diversity were observed at time point 1 between women with and without obesity by total GWG. Significant differences in distal gut β-diversity were also found at time point 1 in obese women by GWG. Within the Bacteroides genus, a significant association was observed by total GWG among obese women which was absent in nonobese women. Women with class III obesity who experienced low GWG had the lowest abundance of distal gut Bacteroides and appreciably higher relative abundance of a consortia of vaginal taxa including Atopobium, Gardnerella, Prevotella, and Sneathia.

Conclusion These results contribute new evidence showing that GWG in combination with obesity and obesity class is associated with an altered distal gut and vaginal composition early in pregnancy among AA women.
Factors Associated with Timeliness of Surgical Repair among Infants with Myelomeningocele: California Perinatal Quality Care Collaborative, 2006 to 2011
Authors: Kancherla Vijaya , Ma Chen , Grant Gerald , Lee Henry C. , Shaw Gary M. , Hintz Susan R. , Carmichael Suzan L.
Published: July 2019

Objective This study aimed to examine factors associated with timely (0–2 days after birth) myelomeningocele surgical repair.

Study Design We examined 2006 to 2011 births from the California Perinatal Quality Care Collaborative, linking to hospital discharge and vital records. Selected maternal, infant, and delivery hospital characteristics were evaluated to understand disparities in timely repair. Poisson regression was used to estimate adjusted risk ratios (aRRs) and 95% confidence intervals (CIs).

Results Overall, 399 of the 450 (89%) infants had a timely repair and approximately 80% of them were delivered in level III/IV hospitals. Infants with hydrocephalus were significantly less likely to have a delayed myelomeningocele repair compared with those without (aRR = 0.22; 95% CI = 0.13, 0.39); infants whose medical care was paid by Medi-Cal or other nonprivate insurance were 2.2 times more likely to have a delayed repair compared with those covered by a private insurance (aRR = 2.23; 95% CI = 1.17, 4.27). Low birth weight was a significant predictor for delayed repair (aRR = 2.06; 95% CI = 1.10, 3.83).

Conclusion There was a significant disparity in myelomenigocele repair based on medical care payer. Families and hospitals should work together for timely repair in hospitals having specialized multidisciplinary teams. Findings from the study can be used to follow best clinical practices for myelomeningocele repair.
Simulation in Neonatal-Perinatal Medicine Fellowship Programs
Authors: Sawyer Taylor , Stavroudis Theodora A. , Ades Anne , Dadiz Rita , Dammann Christiane E. L. , Halamek Louis P. , Moussa Ahmed , Soghier Lamia , Gupta Arika , Aliaga Sofia , Umoren Rachel , French Heather ,   for the Organization of Neonatal-Perinatal Training Program Directors Task Force on Simulation
Published: July 2019

Objective This study aimed to investigate the use of simulation in neonatal-perinatal medicine (NPM) fellowship programs.

Study Design This was a cross-sectional survey of program directors (PDs) and simulation educators in Accreditation Council for Graduate Medical Education (ACGME) accredited NPM fellowship programs.

Results Responses were received from 59 PDs and 52 simulation educators, representing 60% of accredited programs. Of responding programs, 97% used simulation, which most commonly included neonatal resuscitation (94%) and procedural skills (94%) training. The time and scope of simulation use varied significantly. The majority of fellows (51%) received ≤20 hours of simulation during training. The majority of PDs (63%) wanted fellows to receive >20 hours of simulation. Barriers to simulation included lack of faculty time, experience, funding, and curriculum.

Conclusion While the majority of fellowship programs use simulation, the time and scope of fellow exposure to simulation experiences are limited. The creation of a standardized simulation curriculum may address identified barriers to simulation.
Induction of Labor versus Cesarean Delivery in Twin Pregnancies
Authors: Zafman Kelly B. , Rebarber Andrei , Melka Stephanie , Naqvi Mariam , Fox Nathan S.
Published: July 2019

Objective This study was aimed to compare maternal and neonatal outcomes between women with twin pregnancies who underwent induction of labor with those women who had planned Cesarean delivery (CD).

Study Design This is a retrospective cohort study of women with twin pregnancies ≥ 24 weeks with an indication for delivery but not in labor. Two groups were examined, women who underwent induction and women who underwent planned CD. Maternal and neonatal outcomes were compared between groups both for deliveries at gestational age ≥ 37 weeks and < 37 weeks.

Results A total of 453 patients were included. Overall, 212 (46.8%) women underwent induction and 241 (53.2%) underwent planned CD. Women who underwent induction of labor had a high rate of VD, both in the term and preterm groups (69.8 and 73.6%, respectively). Women who underwent induction of labor had reduced maternal length of stay, neonatal length of stay, and blood loss, without any increase in adverse outcomes. Neonatal ventilation of either twin delivered < 37 weeks was higher in the CD compared with induction group (27.5 vs. 9.4%, p < 0.01), but this was not significant on adjusted odds ratio analysis (aOR = 0.71, 95% CI: 0.19–2.66).

Conclusion Labor induction in twin gestations have improved maternal outcomes and similar neonatal outcomes compared with planned CD.