bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanisms and pathways of anti‐inflammatory activity of DPP‐4 inhibitors in cardiovascular and renal protection
Authors: Tomovic Katarina , Lazarevic Jelena , Kocic Gordana , Deljanin‐Ilic Marina , Anderluh Marko , Smelcerovic Andrija
Published: May 2018

Dipeptidyl peptidase‐4 (DPP‐4) cleaves N‐terminal dipeptides, with Pro, Ala or Ser at the penultimate position, and, in that way, modulates biological activity of certain polypeptides. Due to its ubiquitous distribution, many pathological processes are associated with altered DPP‐4 expression and activity. Besides the regulation of glucose metabolism, DPP‐4 also exhibits many other systemic effects, and the inhibition of its activity might lead to cardiovascular and renal protection. Mechanisms underlying these protective effects of DPP‐4 inhibition are ascribed to elevated bioavailability of its substrates, to impacts on mediators and signaling pathways that ameliorate cardiovascular and renal function through the suppression of oxidative stress, inflammation, fibrosis and apoptosis, improved endothelial function and tissue reparation. Inflammation contributes to and promotes progression of cardiovascular and renal disorders. Herein, we discuss cellular and molecular mechanisms mediating the anti‐inflammatory activity of clinically used DPP‐4 inhibitors in cardiovascular and renal protection.
Supplementation of the Diet by Exogenous Myrosinase via Mustard Seeds to Increase the Bioavailability of Sulforaphane in Healthy Human Subjects after the Consumption of Cooked Broccoli
Authors: Okunade Olukayode , Niranjan Keshavan , Ghawi Sameer K. , Kuhnle Gunter , Methven Lisa
Published: May 2018

Scope

Broccoli contains glucosinolate glucoraphanin, which, in the presence of myrosinase, can hydrolyze to isothiocyanate sulforaphane, reported to have anticarcinogenic activity. However, the myrosinase enzyme is denatured on cooking. Addition of an active source of myrosinase, such as from powdered mustard seed, to cooked Brassica vegetables can increase the release of health beneficial isothiocyanates; however, this has not previously been proven in vivo.

Methods and results

The concentration of sulforaphane metabolite (sulforaphane N‐acetyl‐l‐cysteine [SF‐NAC]) in 12 healthy adults after the consumption of 200 g cooked broccoli, with and without 1 g powdered brown mustard, was studied in a randomized crossover design. During the 24‐h period following the consumption of the study sample, all urine was collected. SF‐NAC content was assayed by HPLC. When study subjects ingested cooked broccoli alone, mean urinary SF‐NAC excreted was 9.8 ± 5.1 μmol per g creatinine, and when cooked broccoli was consumed with mustard powder, this increased significantly to 44.7 ± 33.9 μmol SF‐NAC per gram creatinine.

Conclusion

These results conclude that when powdered brown mustard is added to cooked broccoli, the bioavailability of sulforaphane is over four times greater than that from cooked broccoli ingested alone.
Dielectric properties of colon polyps, cancer, and normal mucosa: Ex vivo measurements from 0.5 to 20 GHz
Authors: Guardiola Marta , Buitrago Santiago , Fernández‐Esparrach Glòria , O'Callaghan Joan M. , Romeu Jordi , Cuatrecasas Miriam , Córdova Henry , González Ballester Miguel Ángel , Camara Oscar
Published: May 2018

Purpose

Colorectal cancer is highly preventable by detecting and removing polyps, which are the precursors. Currently, the most accurate test is colonoscopy, but still misses 22% of polyps due to visualization limitations. In this paper, we preliminary assess the potential of microwave imaging and dielectric properties (e.g., complex permittivity) as a complementary method for detecting polyps and cancer tissue in the colon. The dielectric properties of biological tissues have been used in a wide variety of applications, including safety assessment of wireless technologies and design of medical diagnostic or therapeutic techniques (microwave imaging, hyperthermia, and ablation). The main purpose of this work is to measure the complex permittivity of different types of colon polyps, cancer, and normal mucosa in ex vivo human samples to study if the dielectric properties are appropriate for classification purposes.

Methods

The complex permittivity of freshly excised healthy colon tissue, cancer, and histological samples of different types of polyps from 23 patients was characterized using an open‐ended coaxial probe between 0.5 and 20 GHz. The obtained measurements were classified into five tissue groups before applying a data reduction step with a frequency dispersive single‐pole Debye model. The classification was finally compared with pathological analysis of tissue samples, which is the gold standard.

Results

The complex permittivity progressively increases as the tissue degenerates from normal to cancer. When comparing to the gold‐standard histological tissue analysis, the sensitivity and specificity of the proposed method is the following: 100% and 95% for cancer diagnosis; 91% and 62% for adenomas with high‐grade dysplasia; 100% and 61% for adenomas with low‐grade dysplasia; and 100% and 74% for hyperplastic polyps, respectively. In addition, complex permittivity measurements were independent of the lesion shape and size, which is also an interesting property comparing to current colonoscopy techniques.

Conclusions

The contrast in complex permittivities between normal and abnormal colon tissues presented here for the first time demonstrate the potential of these measurements for tissue classification. It also opens the door to the development of a microwave endoscopic device to complement the outcomes of colonoscopy with functional tissue information.
Towards the complex dependence of MTRasym on T1w in amide proton transfer (APT) imaging
Authors: Zu Zhongliang
Published: May 2018

Amide proton transfer (APT) imaging is a variation of chemical exchange saturation transfer MRI that has shown promise in diagnosing tumors, ischemic stroke, multiple sclerosis, traumatic brain injury, etc. Specific quantification of the APT effect is crucial for the interpretation of APT contrast in pathologies. Conventionally, magnetization transfer ratio with asymmetric analysis (MTRasym) has been used to quantify the APT effect. However, some studies indicate that MTRasym is contaminated by water longitudinal relaxation time (T1w), and thus it is necessary to normalize T1w in MTRasym to obtain specific quantification of the APT effect. So far, whether to use MTRasym or the T1w‐normalized MTRasym is still under debate in the field. In this paper, the influence of T1w on the quantification of APT was evaluated through theoretical analysis, numerical simulations, and phantom studies for different experimental conditions. Results indicate that there are two types of T1w effect (T1w recovery and T1w‐related saturation), which have inverse influences on the steady‐state MTRasym. In situations with no or weak direct water saturation (DS) effect, there is only the T1w recovery effect, and MTRasym linearly depends on T1w. In contrast, in situations with significant DS effects, the dependence of MTRasym on T1w is complex, and is dictated by the competition of these two T1w effects. Therefore, by choosing appropriate irradiation powers, MTRasym could be roughly insensitive to T1w. Moreover, in non‐steady‐state acquisitions with very short irradiation time, MTRasym is also roughly insensitive to T1w. Therefore, for steady‐state APT imaging at high fields or with very low irradiation powers, where there are no significant DS effects, it is necessary to normalize T1w to improve the specificity of MTRasym. However, in clinical MRI systems (usually low fields or non‐steady‐state acquisitions), T1w normalization may not be necessary when appropriate sequence parameters are chosen.
Daily associations between objective sleep and consumption of highly palatable food in free‐living conditions
Authors: Chan W. S.
Published: May 2018

Objectives

Prior studies have shown that individuals with shorter sleep duration and later sleep timing consume more highly palatable food (HPF). It is unclear if this relationship exists at the within‐individual level, e.g. if sleeping less or later on one night is associated with greater HPF consumption in the following day in naturalistic environments. This study examined the daily associations between naturalistic sleep and HPF consumption.

Methods

Data were obtained from 78 healthy young adults (age = 20.38 [SD = 2.40] years). Participants carried a wrist actigraph and completed daily diaries tracking food consumption and covariates for seven consecutive days. Data were analysed using mixed models.

Results

Individuals with later bedtime were less likely to consume HPF at breakfast in the following day (odds ratio, OR [between] = 0.55 [0.44, 0.70], p < 0.001). This association was also significant at the within‐individual level (OR (within) = 0.85 [0.74, 0.97], p = 0.016) – sleeping later on one night was associated with 15% decrease in the odds of consuming HPF at breakfast in the following day. Individual with later wake time had greater likelihood of consuming HPF at dinner (OR = 1.34 [1.03, 1.75], p = 0.027).

Conclusions

Sleep schedules characterized by later bedtimes and later wake times were associated with lower HPF consumption earlier in the following day but greater HPF consumption later in the day. This pattern of energy intake might mediate the association between sleep and the risk of obesity.
Optimization of UHMWPE/graphene nanocomposite preparation by single‐supported Ziegler‐Natta catalytic system via RSM
Authors: Shafiee Mojtaba , Akbari Ali
Published: May 2018

In this study, the preparation of ultra‐high molecular weight polyethylene/graphene nanocomposite was carried out using single‐supported Ziegler‐Natta catalyst, and the operational conditions were optimized via response surface methodology. For this purpose, the effect of 3 parameters, monomer pressure, temperature, and molar ratio of [Al] respect to [Ti] on the catalyst productivity and molecular weight of the synthesized nanocomposite polymer, was investigated using the Box‐Behnken experimental design at 3 levels. Monomer pressure, temperature, and molar ratio of [Al] respect to [Ti] were considered as independent variables and catalyst productivity and molecular weight as dependent variables. The highest catalyst productivity and molecular weight were equal to 923 (grPE/mmolTi.h) and 2.04 (million gr/mol), respectively, which were obtained under optimal reaction conditions: temperature of 60°C, pressure of 8 bar, and molar ratio of 185. Finally, in order to investigate the morphology and nanoparticle dispersion in polymer matrix, scanning electron microscope and X‐ray diffraction were used. The results indicate the homogenous dispersion of graphene nanoparticles in polymer matrix.
Preparation and characterization of PVDF‐based blend membranes as polymer electrolyte membranes in fuel cells: Study of factor affecting the proton conductivity behavior
Authors: Ahmadian‐Alam Leila , Mahdavi Hossein
Published: May 2018

There is a huge demand especially for polyvinylidene fluoride (PVDF) and its copolymers to provide high performance solid polymer electrolytes for use as an electrolyte in energy supply systems. In this regard, the blending approach was used to prepare PVDF‐based proton exchange membranes and focused on the study of factor affecting their proton conductivity behavior. Thus, a series of copolymers consisting of poly (methyl methacrylate) (PMMA), polyacrylonitrile (PAN), and poly(2‐acrylamido‐2‐methyl‐l‐propanesulfonic acid) (PAMPS) as sulfonated segments were synthesized and blended with PVDF matrix in order to create proton transport sites in PVDF matrix. It was found that addition of PMMA‐co‐PAMPS and PAN‐co‐PAMPS copolymers resulted in a significant increase in porosity, which favored the water uptake and proton transport at ambient temperature. Furthermore, crystallinity degree of the PVDF‐based blend membranes was increased by addition of the related copolymers, which is mainly attributed to formation of hydrogen bonding interaction between PVDF matrix and the synthesized copolymers, and led to a slight decrease in proton conductivity behavior of blend membranes. From impedance data, the proton conductivity of the PVDF/PMMA‐co‐PAMPS and PVDF/PAN‐co‐PAMPS blend membranes increases to 10 and 8.4 mS cm−1 by adding only 50% of the related copolymer (at 25°C), respectively. Also, the blend membranes containing 30% sulfonated copolymers showed a power density as high as 34.30 and 30.10 mW cm−2 at peak current density of 140 and 79.45 mA cm−2 for the PVDF/PMMA‐co‐PAMPS and PVDF/PAN‐co‐PAMPS blend membranes, respectively. A reduction in the tensile strength was observed by the addition of amphiphilic copolymer, whereas the elongation at break of all blend membranes was raised.
Effect of continuous elongational flow on structure and properties of poly(L‐lactic acid)/poly(ethylene glycol) blend and its organo‐modified montmorillonite nanocomposites
Authors: Wu Ting , He Yue , Qu Jin‐Ping
Published: May 2018

An innovative eccentric rotor extruder, which can generate continuous elongation flow, was used to fabricate the poly(L‐lactic acid) (PLLA)/poly(ethylene glycol) (PEG) blends and PLLA/PEG/organo‐modified montmorillonite (OMMT) nanocomposites in different PEG and OMMT content. The morphology was characterized by X‐ray diffractometer (XRD) and transmission electron microscope, showing that the OMMT nanoparticles were highly intercalated or/and exfoliated in the polymer matrix. The rheological behavior was investigated by dynamic rheological measurements, showing that the OMMT nanoparticles dispersed well in the matrix to form OMMT percolation network structure. The crystallization behavior and crystalline structures were studied by differential scanning calorimetry and XRD, respectively, showing that the addition of PEG significantly increased the crystallinity of PLLA and the presence of OMMT further speed up the crystallization rate of plasticized PLLA, which was also proved by the increasing spherulite growth rate and the formation of more perfect crystal structure acquired from polarizing optical microscopy test. However, the crystallization rate and crystallinity had a slight downward trend at high OMMT content because of the inhibition effect of OMMT percolation network structure. Moreover, the thermogravimetric analyzer measurement indicated that the presence of OMMT can significantly improve the thermal stability of PLLA/PEG blends. POLYM. COMPOS., 40:E617–E628, 2019. © 2018 Society of Plastics Engineers
Preschool teachers and classroom aides: Same context, similar perceptions of children's behaviors?
Authors: Major Sofia O. , Seabra‐Santos Maria J. , Gaspar Maria F.
Published: May 2018

This study explored the correspondence and differences between school staff perceptions of preschool children's social skills and behavior problems. One hundred preschoolers were assessed by 14 pairs of teachers and classroom aides with the Preschool and Kindergarten Behavior Scales – 2nd Edition (PKBS‐2 Portuguese version). Indexes of agreement and disagreement were calculated. Risk levels and item analyses of PKBS‐2 scores according to both informants' ratings were compared. A higher level of agreement was obtained for social skills scores than for behavior problems (mean correlation of .62). No statistically significant differences between informants were obtained for the risk levels, and item analyses revealed a similar pattern of behaviors that were most and least rated by both informants. Results indicate that the classroom aides' perspective on preschool assessment represents a reliable input, which justifies that they network with teachers in addressing preschoolers' social‐emotional and behavioral challenges.
In Silico Prediction and Validation of Novel RNA Binding Proteins and Residues in the Human Proteome
Authors: Chowdhury Shomeek , Zhang Jian , Kurgan Lukasz
Published: May 2018

Deciphering a complete landscape of protein–RNA interactions in the human proteome remains an elusive challenge. We computationally elucidate RNA binding proteins (RBPs) using an approach that complements previous efforts. We employ two modern complementary sequence‐based methods that provide accurate predictions from the structured and the intrinsically disordered sequences, even in the absence of sequence similarity to the known RBPs. We generate and analyze putative RNA binding residues on the whole proteome scale. Using a conservative setting that ensures low, 5% false positive rate, we identify 1511 putative RBPs that include 281 known RBPs and 166 RBPs that were previously predicted. We empirically demonstrate that these overlaps are statistically significant. We also validate the putative RBPs based on two major hallmarks of their RNA binding residues: high levels of evolutionary conservation and enrichment in charged amino acids. Moreover, we show that the novel RBPs are significantly under‐annotated functionally which coincides with the fact that they were not yet found to interact with RNAs. We provide two examples of our novel putative RBPs for which there is recent evidence of their interactions with RNAs. The dataset of novel putative RBPs and RNA binding residues for the future hypothesis generation is provided in the Supporting Information.
Terbium‐Doped Layered Yttrium Hydroxide Nanocone: Controlled Synthesis, Structure Variations, Phase Conversion to Oxide/Oxysulfate Nanocone and Their Luminescence Properties
Authors: Xiao Yan , Zhong Yishun , Liu Xiaohe , Zhang Ning , Liang Shuquan , Ma Renzhi
Published: May 2018

It is demonstrated herein that a series of terbium ions (Tb3+)‐doped layered yttrium hydroxide (LYH:Tb) nanocones (NCs) intercalating dodecyl sulfate (C12H25SO4, DS) anions can be successfully synthesized in large quantities through a facile hydrothermal strategy. The DS anions in the interlayer gallery of LYH:Tb NCs can be readily modified with various anions (such as NO3
−, Cl−, and CH3COO−) through a convenient anion‐exchange procedure. The luminescent properties of LYH:Tb NCs are sensitively influenced by the dopant concentration and the interlayer anions. In particular, the original DS−‐intercalated form and the anion‐exchanged product can be topotactically converted into oxysulfates and oxides with original conical features through a calcination process at 750 °C for 2 h, respectively. Compared with Y2O3:Tb NCs, Y2O2SO4:Tb NCs exhibit efficient luminescent properties due to the stronger deformation of the crystal field. More interestingly, the conical structures also exhibit superior luminescent properties over the lamellar objects, originating from the extreme curvature and perturbation of crystal field, which are promising candidates for potential applications in optical and display devices.
Bottom‐Up Synthesis of Carbon Quantum Dots With High Performance Photo‐ and Electroluminescence
Authors: Kim Hong Hee , Lee Yeon Ju , Park Chanho , Yu Seunggun , Won Sung Ok , Seo Won‐Seon , Park Cheolmin , Choi Won Kook
Published: May 2018

Although carbon quantum dots (CQDs) are of great interest because of cost effectiveness and environmental compatibility with the facile tunability of their optical properties, poor photo‐ and electroluminescence (EL) of CQDs limits further implementation. Here, a novel bottom‐up synthetic route for fabricating highly crystalline CQDs suitable for high‐brightness blue light‐emitting diodes is demonstrated. The two‐step solution process is based on time‐controlled thermal carbonization of citric acid, followed by ligand exchange of the CQDs with oleylamine (OA) in solution. Carbonization allows for the nucleation and growth of crystalline CQDs, while OA treatment disperses the CQDs and stabilizes the solution, giving rise to CQDs with low structural defects and uniform sizes. The systematic study reveals the origin of the light emission of OA‐treated CQDs by photoluminescence (PL) analysis, which yields a high quantum efficiency of ≈30%. The photoluminescence‐optimized OA‐treated CQDs exhibit excellent blue EL performance with a low turn‐on voltage of ≈4 V and high brightness of 308 cd m−2; a negligible voltage‐dependent color shift when they are employed to an inverted light‐emitting diode.
The use of light's criteria in hospitalized children with a pleural effusion of unknown etiology
Authors: McGraw Matthew D. , Robison Kyle , Kupfer Oren , Brinton John T. , Stillwell Paul C.
Published: May 2018

Objective

Pleural effusions are common in pediatrics. When the etiology of a pleural effusion remains unknown, adult literature recommends the use of Light's criteria to differentiate a transudate from an exudate. Pediatricians may rely on adult literature for the diagnostic management of pleural effusions as Light's criteria has not been validated in children. The purpose of this study was to review the use of Light's criteria in hospitalized children with a pleural effusion of unknown etiology.

Methods

Retrospective review was performed on children hospitalized with a pleural effusion requiring chest tube placement or thoracentesis between January 1, 2016 to January 1, 2017 at Children's Hospital Colorado. Charts were reviewed for primary team, use of Light's criteria, pleural effusion diagnosis, and 30‐day recurrence of repeat intervention or fluid analysis.

Results

Sixty‐eight patients were hospitalized with a pleural effusion of unknown etiology requiring intervention. Only 16 pleural effusions (24%) were classified using Light's criteria. In those patients for whom Light's criteria was used, a diagnosis or change in management occurred in 10 of 16 patients (63%). Pleural effusions were most common on the cardiology service (26/68). Use of Light's criteria was most frequent on the oncology service (7/8). Thirty‐day need for repeat intervention was lower in those with Light's criteria (13%) compared to those without (27%).

Conclusions

Light's criteria were utilized infrequently in hospitalized children with a pleural effusion of unknown etiology at a single institution. There was considerable practice variation among provider teams. When utilized, Light's criteria assisted in making a diagnosis or changing management in many patients, and may lead to a reduction in 30‐day recurrence requiring repeat intervention.
Target site mutations and cytochrome P450s confer resistance to fenoxaprop‐P‐ethyl and mesosulfuron‐methyl in Alopecurus aequalis
Authors: Zhao Ning , Yan Yanyan , Ge Lu'an , Zhu Baolin , Liu Weitang , Wang Jinxin
Published: May 2018

BACKGROUND

Shortawn foxtail (Alopecurus aequalis Sobol.) is a competitive grass weed infesting winter wheat‐ and canola‐growing fields in China. In May 2016, a suspected A. aequalis resistant population AHTC‐06 that survived fenoxaprop‐P‐ethyl and mesosulfuron‐methyl applied at their field‐recommended rates was collected from a wheat field in Jinji County, Anhui Province, China. This study aimed to determine the resistance profile of this AHTC‐06 population to ACCase‐ and ALS‐inhibitors, and to investigate its mechanisms of resistance to fenoxaprop‐P‐ethyl and mesosulfuron‐methyl.

RESULTS

Two mutations, a common Ile‐2041‐Asn (ACCase gene) and a very rare Pro‐197‐Tyr (ALS1 gene), were both identified in resistant individual plants. The homozygous subpopulation AHTC‐06F1 for the two mutations was generated, and it showed broad‐spectrum resistance to APPs, DENs, and ALS‐inhibiting herbicides of all five chemical families tested, with resistance index (RI) values that ranged from 2.2 to 36.5. In vitro ALS activity assays showed the ALS from the resistant population was insensitive to all the tested ALS inhibitors, with RI values ranging from 3.10 to 22.51. Pre‐treatment with piperonyl butoxide (PBO) and malathion significantly (P < 0.05) reversed the weed's resistance to fenoxaprop‐P‐ethyl and mesosulfuron‐methyl, respectively. Two P450 genes, c21190_g1 and c43350_g3, were constitutively overexpressed and mesosulfuron‐methyl‐induced upregulated in resistant plants, for which c43350_g3 was also fenoxaprop‐P‐ethyl‐induced upregulated.

CONCLUSION

This study confirms the first case of a grass weed featuring broad‐spectrum resistance to ALS‐inhibiting herbicides due to a Pro‐197‐Tyr mutation in the ALS gene. Fenoxaprop‐P‐ethyl and mesosulfuron‐methyl resistances in AHTC‐06 plants were conferred by target site mutations and P450s‐based metabolism. © 2018 Society of Chemical Industry
An investigation of the effects of curcumin on iron overload, hepcidin level, and liver function in β‐thalassemia major patients: A double‐blind randomized controlled clinical trial
Authors: Mohammadi Elahe , Tamaddoni Ahmad , Qujeq Durdi , Nasseri Esmat , Zayeri Farid , Zand Hamid , Gholami Mahdi , Mir Seyed Mostafa
Published: May 2018

This study investigated the effects of curcumin, the active polyphenol in turmeric, on iron overload, hepcidin level, and liver function in β‐thalassemia major patients. This double‐blind randomized controlled clinical trial was conducted on 68 β‐thalassemia major patients. The subjects were randomly divided into 2 groups to receive either 500 mg curcumin capsules (total: 1,000 mg) twice daily or placebo for 12 weeks. Dietary intakes and biochemical variables including hemoglobin, transferrin saturation, total iron binding capacity, nontransferrin bound iron (NTBI), ferritin, hepcidin, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were assessed at the beginning and end of the trial. Curcumin significantly reduced serum levels of NTBI (2.83 ± 1.08 compared with 2.22 ± 0.97 μmol/L, p = .001), ALT (42.86 ± 11.15 compared with 40.60 ± 9.89 U/L, p = .018), and AST (49.45 ± 12.39 compared with 46.30 ± 10.85 U/L, p = .002) at the end of the study. Based on analysis of covariance, a significant decrease was also observed in levels of NTBI (2.22 ± 0.97 vs. 2.55 ± 0.94 μmol/L, p = .026), ALT (40.60 ± 9.89 vs. 45.01 ± 10.42 U/L, p = .004), and AST (46.30 ± 10.85 vs. 50.99 ± 9.36 U/L, p = .009) in curcumin group in comparison with placebo group. There were no significant changes in hepcidin and other variables in any of the 2 groups. Curcumin administration alleviated iron burden and liver dysfunction by reducing NTBI, ALT, and AST levels in patients with β‐thalassemia major.
Intervention of curcumin on oral pharmacokinetics of daclatasvir in rat: A possible risk for long‐term use
Authors: Dogra Ashish , Bhatt Shipra , Magotra Asmita , Sharma Anjna , Kotwal Pankul , Gour Abhishek , Wazir Priya , Singh Gurdarshan , Nandi Utpal
Published: May 2018

Curcumin, a natural diarylheptanoid, is extensively used as a food additive or dietary supplement on the regular basis. It is known to have potential to encumber the drug transporters and hepatic drug metabolizing enzymes that lead to pharmacokinetic interactions with drug or food. Daclatasvir is a new orally acting drug for the treatment of chronic Hepatitis C Virus infections. This is a substrate of P‐glycoprotein and CYP3A4 that are involved in the major pharmacokinetic interaction. Hence, the studies' aim is to assess for any possible pharmacokinetic interactions. Pharmacokinetic studies of daclatasvir in presence or absence of curcumin were carried out in Wistar rats following oral administration. Parallelly, the oral pharmacokinetics of daclatasvir was also determined in the presence of ketoconazole or quinidine. Studies revealed that plasma level of daclatasvir was not altered significantly during concomitant single dose administration of curcumin, whereas significantly decreased upon pretreatment for 7 days with curcumin at high dose level. Ketoconazole and quinidine markedly increase daclatasvir exposure following concomitant administration with daclatasvir. It can be concluded that dose adjustment is unlikely to be required for intermittent use of curcumin at low dose but cautious for chronic and concomitant use of curcumin at a high dose.
Improving writing skills through technology‐based instruction: A meta‐analysis
Authors: Little Callie W. , Clark Jacourie C. , Tani Novell E. , Connor Carol McDonald
Published: May 2018

The present study examined the effect of technology‐based writing instruction on writing outcomes using meta‐analytic methods. Additionally, this study investigated whether characteristics of study, sample, and outcome moderated the effect of technology‐based writing instruction. Six studies were coded resulting in 11 extracted effect sizes. Results revealed that the weighted average effect size for technology‐based writing instruction was 0.28, suggesting an educationally relevant and impactful effect of education technology on writing outcomes. Several moderators were included in this meta‐analysis, but did not significantly influence effect sizes. One exception was learning disability (LD) status; however, these results should be interpreted with caution as only one study included an LD sample. Overall, these results support previous research and provide knowledge of the populations that are potentially impacted by technology‐based writing instruction. Previous literature suggests technology‐based writing instruction may supplement teachers’ efforts to deliver instruction and provide practice time to students, affording students extra opportunities to engage with writing both in and out of the classroom; however, more research is required to determine the exact mechanisms through which technology may impact writing skills. Recommendations for reporting techniques and directions for future research in development and implementation of technology‐based writing instruction are discussed.
Content of highly unsaturated fatty acids in fish from rivers of contrasting temperature
Authors: Sushchik N.N. , Zuev I.V. , Kalachova G.S. , Ageev A.V. , Gladyshev M.I.
Published: May 2018

Contents of highly unsaturated long‐chain fatty acids of omega‐3 family (HUFA); eicosapentaenoic acid (EPA; 20:5n‐3); and docosahexaenoic acid (DHA; 22:6n‐3) are the principal indicators of the nutritive quality of fish for humans. Effects of environmental factors, first of all water temperature, on EPA and DHA contents in fish tissue are not currently completely understood. To reveal the putative effect of water temperature, fatty acid composition and contents were studied for 6 fish species, inhabiting the cold waters of the Yenisei River (Siberia, Russia) downstream of a dam (hypolimnetic release from reservoir) and its adjacent warm water tributaries (the Mana River and the Kacha River). It was hypothesized that (a) fish species from the cold river would have higher HUFA contents than fish from the warm rivers and (b) temperature would be negatively correlated with HUFA content in fish species. Using gas chromatography–mass spectrometry, distinct species‐specific fatty acid profiles were observed, whereas contents of the essential fatty acids, EPA and DHA, in fish species from the cold Yenisei River were in general similar to that from warm tributaries. Thus, in contrast to the first hypothesis, phylogenetic factors overweighed the effect of water temperature and food (benthic invertebrate) composition, on fatty acid composition and HUFA content in fish. For the second hypothesis, for the 2 species inhabiting both cold and warm rivers, only one had higher EPA and DHA content at lower temperatures. Consequently, the response of EPA and DHA content in fish tissue to temperature variations may be species‐specific.
Biofilm early stage development in two nutrient‐rich streams with different urban impacts
Authors: Cochero J. , Nicolosi Gelis M.M. , Sathicq M.B. , Gómez N.
Published: May 2018

The aim of this study was to describe the colonization of the biofilm during its early stages under different concentrations of nutrients and organic matter, specifically in urban streams influenced by agriculture and urbanization. We hypothesized that in a stream with higher concentrations of nutrients and organic matter, the initial biomass growth would be faster, and the changes in the structure of the community would be greater. Sterile glass substrates were placed in 2 urban streams that differed in nutrient and organic matter concentrations; samples were collected during their first week of colonization to measure total biomass, bacterial biomass, chlorophyll a, activity of the electron transfer system, and the community composition. Results show that biofilm development in both streams began within a few hours and differed under different conditions of nutrients; in the stream with a better water quality, the colonization dynamics consisted of 2 increments of bacterial biomass linked with an increase of algal biomass. In the urban stream with higher nutrient and organic matter concentrations, biofilm development was slower and consisted of a simultaneous increase of bacteria and algae, consistent with a lower electron transfer system activity. Therefore, the dynamics of the colonization process in addition to those characteristics of the fully developed biofilm could have potential applications in water monitoring of urban streams.
Graphene oxide layers modified by irradiation with 1.0 MeV Au+ ions
Authors: Malinský Petr , Cutroneo Mariapompea , Macková Anna , Hnatowicz Vladimir , Szökölová Kateřina , Bohačová Marie , Luxa Jan , Sofer Zdeněk
Published: May 2018

Graphene oxide (GO) foils were modified by irradiation using 1.0 MeV Au+ ions, and their elemental composition before and after the ion irradiation was investigated using Rutherford back‐scattering spectroscopy (RBS). The surface morphology was studied using SEM, and changes in elemental composition and structure of GO in shallow subsurface were characterized by various spectroscopy techniques including X‐ray photoelectron spectroscopy and Raman spectroscopy. Electrical properties were determined using standard 2‐point method. The analyses indicate that the Au irradiation up to 1.0 × 1015 cm−1 results in removal of oxygen functionalities and growth of graphene domains, leading to a surface conductivity increase dependent on the applied ion fluence. The Au irradiation with excessive ion fluencies leads to the amorphization of GO foil structure.
Some findings on zero‐inflated and hurdle poisson models for disease mapping
Authors: Corpas‐Burgos Francisca , García‐Donato Gonzalo , Martinez‐Beneito Miguel A.
Published: May 2018

Zero excess in the study of geographically referenced mortality data sets has been the focus of considerable attention in the literature, with zero‐inflation being the most common procedure to handle this lack of fit. Although hurdle models have also been used in disease mapping studies, their use is more rare. We show in this paper that models using particular treatments of zero excesses are often required for achieving appropriate fits in regular mortality studies since, otherwise, geographical units with low expected counts are oversmoothed. However, as also shown, an indiscriminate treatment of zero excess may be unnecessary and has a problematic implementation. In this regard, we find that naive zero‐inflation and hurdle models, without an explicit modeling of the probabilities of zeroes, do not fix zero excesses problems well enough and are clearly unsatisfactory. Results sharply suggest the need for an explicit modeling of the probabilities that should vary across areal units. Unfortunately, these more flexible modeling strategies can easily lead to improper posterior distributions as we prove in several theoretical results. Those procedures have been repeatedly used in the disease mapping literature, and one should bear these issues in mind in order to propose valid models. We finally propose several valid modeling alternatives according to the results mentioned that are suitable for fitting zero excesses. We show that those proposals fix zero excesses problems and correct the mentioned oversmoothing of risks in low populated units depicting geographic patterns more suited to the data.
Metal‐Free Debromination of 5‐Bromopyrimidine Derivatives Using DMF/Trialkylamine as the Hydrogen Source
Authors: Mousavi Mahsa , Bakavoli Mehdi , Shiri Ali , Tajabadi Javad
Published: May 2018

Attempted heterocyclization of 5‐bromo‐2,4‐diamino‐6‐substituted pyrimidines in a mixture of DMF and trialkylamines (Et3N or N,N‐diisopropylethylamine) under mild conditions, led to the formation of new dehalogenated derivatives as the main product. This metal‐free catalyzed debromination process presents DMF/R3N combination as a potential metal‐free reductive system.
A Two‐Stage Annealing Strategy for Crystallization Control of CH3NH3PbI3 Films toward Highly Reproducible Perovskite Solar Cells
Authors: Zhang Jing , Liang Wensheng , Yu Wei , Yu Shuwen , Wu Yiliang , Guo Xin , Liu Shengzhong (Frank) , Li Can
Published: May 2018

The solvent‐engineering method is widely used to fabricate top‐performing perovskite solar cells, which, however, usually exhibit inferior reproducibility. Herein, a two‐stage annealing (TSA) strategy is demonstrated for processing of perovskite films, namely, annealing the intermediate phase at 60 °C for the first stage then at 100 °C for the second stage. Compared to conventional direct annealing temperature (DHA) at 100 °C, using this strategy, MAPbI3 films become more controllable, leading to superior film uniformity and device reproducibility with the champion device efficiency reaching 19.8%. More specifically, the coefficient of variation of efficiency for 49 cells is reduced to 5.9%, compared to 9.8% for that using DHA. The TSA process is carefully studied using Fourier transform infrared spectroscopy, X‐ray diffraction, and UV–vis absorption spectroscopy. It is found that in comparison with DHA the formation of hydrogen bonding and crystallization of perovskite are much slower and can be better controlled when using TSA. The improvements in film uniformity and device reproducibility are attributed to: 1) controllable MAPbI3 crystal growth stemming from the progressive formation of hydrogen bonding between methylammonium and halide; 2) suppression of intermediate phase film dewetting, which is believed to be due to its decreased mobility at the initial low‐temperature annealing stage.
Biological Spiking Synapse Constructed from Solution Processed Bimetal Core–Shell Nanoparticle Based Composites
Authors: Zhou Li , Mao Jing‐Yu , Ren Yi , Yang Jia‐Qin , Zhang Shi‐Rui , Zhou Ye , Liao Qiufan , Zeng Yu‐Jia , Shan Haiquan , Xu Zongxiang , Fu Jingjing , Wang Yan , Chen Xiaoli , Lv Ziyu , Han Su‐Ting , Roy Vellaisamy A. L.
Published: May 2018

Inspired by the highly parallel processing power and low energy consumption of the biological nervous system, the development of a neuromorphic computing paradigm to mimic brain‐like behaviors with electronic components based artificial synapses may play key roles to eliminate the von Neumann bottleneck. Random resistive access memory (RRAM) is suitable for artificial synapse due to its tunable bidirectional switching behavior. In this work, a biological spiking synapse is developed with solution processed Au@Ag core–shell nanoparticle (NP)‐based RRAM. The device shows highly controllable bistable resistive switching behavior due to the favorable Ag ions migration and filament formation in the composite film, and the good charge trapping and transport property of Au@Ag NPs. Moreover, comprehensive synaptic functions of biosynapse including paired‐pulse depression, paired‐pulse facilitation, post‐tetanic potentiation, spike‐time‐dependent plasticity, and the transformation from short‐term plasticity to long‐term plasticity are emulated. This work demonstrates that the solution processed bimetal core–shell nanoparticle‐based biological spiking synapse provides great potential for the further creation of a neuromorphic computing system.
Recent Advances in Novel Nanostructuring Methods of Perovskite Electrocatalysts for Energy‐Related Applications
Authors: Xu Xiaomin , Wang Wei , Zhou Wei , Shao Zongping
Published: May 2018

Perovskite oxides hold great promise as efficient electrocatalysts for various energy‐related applications owing to their low cost, flexible structure, and high intrinsic catalytic activity. However, conventional synthetic methods can only obtain perovskite catalysts with large particle sizes, small surface areas, and few morphological features, leading to limited catalytic activity and thus posing a major challenge toward real‐world applications. Reducing the size of bulk perovskites down to the nanosize represents an efficient way to improve the electrocatalytic performance. A comprehensive overview of recent progress in the nanostructuring of perovskites for catalyzing several key reactions in metal–air batteries, water splitting, and solid oxide fuel cells is provided. A range of synthetic protocols for making perovskite nanostructures are summarized, followed by an emphasis on how each method can be tailored to obtain high‐performing perovskite nanocatalysts. These recent advances highlight the enormous potential of nanosized perovskites for facilitating the electrocatalytic reactions. The remaining challenges and future directions are pointed out for the development of next‐generation perovskite‐based nanostructured catalysts.
Application of systems engineering to structuring acquisition decisions for marine emission reduction technologies
Authors: Aspen Dina Margrethe , Haskins Cecilia , Fet Annik Magerholm
Published: May 2018

Due to increasingly strict environmental regulation of marine transportation, vessel operators and other stakeholders are required to evaluate feasible compliance measures in the face of multiple criteria and with attention to uncertainties and risks. Several methods and models within operations research have been applied to explore such decision contexts, but little is reported on the problem structure itself and the key values, concerns, and uncertainties that apply to them. The objective of the paper is to present a problem structure for acquisition of marine emission reduction technologies in the Norwegian ferry fleet drawing on methods from decision science and systems engineering. To attain this objective, we utilize the SPADE methodology, which details five problem‐solving activities covering stakeholders, problem formulation, alternatives, decisions, and continuous evaluation. Each activity is informed by data collected through stakeholder interviews and literature analysis to establish an initial representation of acquisition decision issues. To keep a consistent and traceable problem structure, we provide a stakeholder diagram, value network, systemigram, and decision hierarchy centered around stakeholders and their values. These models may serve to inform decision‐makers in the development and appraisal of emission reduction technologies and strategies. The paper demonstrates the application of systems engineering as a problem‐structuring framework for complex, multidimensional marine technology acquisition decisions.
Software obsolescence risk assessment approach using multicriteria decision‐making
Authors: Bowlds Ted F. , Fossaceca John M. , Iammartino Ronald
Published: May 2018

System obsolescence issues are a routine occurrence, especially for systems with a high utilization of commercial electronic components or software applications with a long operational life. The extended length of a system's development can often result in obsolescence well before system production and fielding begins. Obsolescence affects individual electronic components and availability of materials, as well as access to experienced personnel, processes, and software. Legacy application software obsolescence is influenced by multiple factors. Included in these factors are hardware obsolescence, increased software maintenance, commercial off‐the‐shelf software obsolescence, growth in technical debt, growth in complexity, and a lack of embedded business rule documentation. These criteria influence subjective management decisions in the remediation of current or future obsolescence risk. A multicriteria decision‐making (MCDM) approach is proposed to evaluate the impact of multiple obsolescence elements over the life cycle of a software application with consideration for the knowledge, preference, and subjectivity of experts to better inform the risk assessment and timing of future mitigation strategies. The resulting MCDM score provides a break point for a quantifiable increase in obsolescence risk.
Using a systems engineering framework for additive manufacturing
Authors: Togwe Thembani , Tanju Bereket , Eveleigh Timothy J.
Published: May 2018

System engineering life cycles can be used by enterprises to make assessments that facilitate the effective insertion of technology into existing practices. The updated systems life cycle processes standard, ISO/IEC/IEEE 15288:2015, is examined to assess additive manufacturing (AM), also known as 3D printing. AM's digital nature emerges as a major theme. AM's introduction into the aviation spare part supply chain is also explored using a project crashing illustration. The illustration showed that AM could be leveraged as a project crashing tool. In addition, the use of the ISO/IEC/IEEE 15288:2015 standard revealed network configurations that could be explored to broaden AM's use and obtain additional value, both of which could justify the use of AM. In this study, we suggest the multiple effects of AM on the systems engineering development life cycle.
Entropy‐based system assessment metric for determining architecture's robustness to different stakeholder perspectives
Authors: Ahn Jaemyung , Choi Minkyu , Suh Eun Suk
Published: May 2018

In this study, a new system assessment metric is proposed to evaluate the robustness of system architectures to different stakeholder perspectives and decomposition preferences. Typically, the decomposition of a system architecture into a modular configuration is based on the function‐based perspective of the design teams, which can be different from the perspectives of other stakeholders such as the manufacturing teams and field service organization. In this paper, a system architecture is decomposed into different modular configurations on the basis of the preferred perspectives of various stakeholders. The generated configurations are then compared to function‐based modular configurations in terms of the diffusion of the original function‐based module components into modules generated from different perspectives. The degree of diffusion is measured using a newly proposed entropy based metric referred to as the module diffusion index. The proposed metric provides stakeholders with a quantifiable measure of the robustness of a particular system architecture with respect to the preferred decomposition strategy of different stakeholders. The proposed metric can be used to assess different system architectures in terms of their robustness to perspective‐based decompositions. A case study is conducted wherein different mechanical clock architectures are assessed in terms of the robustness to different perspective‐based decompositions to demonstrate the effectiveness of the proposed metric.
Cu(I)‐Catalyzed Cross‐Coupling of Diazo Compounds with Terminal Alkynes: An Efficient Access to Allenes
Authors: Hossain Mohammad Lokman , Wang Jianbo
Published: May 2018

Cu(I)‐catalyzed reaction of diazo compounds generates a Cu(I)‐carbene intermediate that undergoes diverse transformations. In the past few years, the diazo compounds (or their precursor N‐tosylhydrazones) have been established as cross‐coupling partners under transition‐metal catalysis, affording various organic compounds. Particularly the breakthrough has been made in allene synthesis by Cu(I)‐catalyzed carbene coupling with terminal alkynes. Moreover, the Cu(I)‐catalyzed coupling reaction of diazo compounds with terminal alkynes generates allene intermediate that undergoes tandem cyclization/coupling to afford cyclic compounds. This review article summarizes the most recent developments in allene synthesis based on the Cu(I)‐carbene coupling reactions and the utilization of allene intermediates in tandem reactions.