bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phase Diversity of Nickel Phosphides in Oxygen Reduction Catalysis
Authors: Razmjooei Fatemeh , Pak Chanho , Yu Jong‐Sung 
Published: April 2018

AbstractMotivated by the challenge to find a low‐cost catalyst with high activity for the oxygen reduction reaction (ORR), transition metal phosphides (TMPs) appear to be one of the most burgeoning alternatives to noble metal based electrocatalysts. In addition to the low cost, TMPs have numerous interesting features such as high conductivity and chemical stability. Since, the catalytic activity of TMPs is highly dependent on the metal/phosphorous ratio, herein, we report the investigation of nickel‐phosphide/carbon composites of different stoichiometries (NixPy/C) with tractable nickel phosphide phases as promising electrocatalyst for ORR under alkaline and acidic conditions. The NixPy/C composites are obtained by carbonization of a Ni‐struvite (NiNH4PO4 ⋅ H2O) coated phenol‐formaldehyde resin at different temperatures, resulting in variations of the formed NixPy phases. As expected, it is found that the electrocatalytic ORR performance of the NixPy/C composites highly depends on the predominant phase of nickel phosphide formed. The highest catalytic activity for ORR in alkaline as well as acidic media was found for the NixPy/C composite with the highest proportion of Ni2P as a predominant phase, obtained at 800 °C. For composites with NiP2 and Ni12P5 as the predominant phase, obtained at lower and higher temperatures, respectively, a lower catalytic activity was found.
Supramolecular Assembly of Peptide and Metallopeptide Gelators and Their Stimuli‐Responsive Properties in Biomedical Applications
Authors: Falcone Natashya , Kraatz Heinz‐Bernhard 
Published: April 2018

AbstractSupramolecular gels are a fascinating class of soft materials that have attracted significant attention in recent years. They are composed of small molecule gelators that assemble into supramolecular network structures. The resulting space is filled with solvent. Some gel materials are able to respond to various stimuli making them attractive drug delivery vehicles and as matrices for tissue regeneration. Peptide‐based gel materials are particularly attractive as they possess numerous advantages including biocompatibility and biodegradability. Stimuli‐responsive peptides that alter properties as a function of pH, redox, temperature, and enzymes offer the potential to create materials with tunable characteristics. In addition, the ability of metal ions to improve the strength of gelation or act as a scaffold has become an interesting approach to develop dynamic peptide gel materials. In this review, the stimuli‐responsive properties (pH, redox, temperature, and enzyme responsive properties), as well as the biocompatible/‐degradable nature of the peptide gelators are highlighted. In addition, metal ions are discussed as a stimulus to enhance peptide gelation and a number of potential applications of these peptide gelators are provided with an outlook on future directions.
DNA Oxidation Photoinduced by Norharmane Rhenium(I) Polypyridyl Complexes: Effect of the Bidentate N,N′‐Ligands on the Damage Profile
Authors: Maisuls Iván , Cabrerizo Franco M. , David‐Gara Pedro M. , Epe Bernd , Ruiz Gustavo T. 
Published: April 2018

AbstractReI‐polypyridyl complexes have interesting and distinctive photochemical and photosensitizing properties. This work describes the capability to induce (or photoinduce) DNA damage of three ReI‐complexes with a naturally occurring alkaloid called norharmane (nHo) as ligand: [Re(CO)3(nHo)(L)]CF3SO3 where L=2,2′‐bipyridine (ReBpy), phenanthroline (RePhen) or dipyrido[3,2‐a:2′,3′‐c]phenazine (ReDppz). The interaction of the complexes with DNA was investigated by steady‐state and time‐resolved spectroscopy. Data show that the mode and strength of interaction depend on the chemical structure of the bidentate ligand. The complexes show a major static contribution to the overall interaction, giving rise to the formation of noncovalent adducts with DNA, and the particular trend observed was RePhen>ReDppz>ReBpy. Photo‐oxidation at the purine bases represents the major DNA damaging mechanism. RePhen also induces single‐strand breaks in a yield similar to that of base damage, suggesting an additional photosensitizing pathway. We also performed the Ames test to evaluate the cytotoxic and mutagenic properties of both non‐irradiated and photoexcited complexes. RePhen, but not the other complexes, turned out to be both toxic and phototoxic for the bacteria.
Ultrafast Adiabatic Photodehydration of 2‐Hydroxymethylphenol and the Formation of Quinone Methide
Authors: Škalamera Đani , Antol Ivana , Mlinarić‐Majerski Kata , Vančik Hrvoj , Phillips David Lee , Ma Jiani , Basarić Nikola 
Published: April 2018

AbstractThe photochemical reactivity of 2‐hydroxymethylphenol (1) was investigated experimentally by photochemistry under cryogenic conditions, by detecting reactive intermediates by IR spectroscopy, and by using nanosecond and femtosecond transient absorption spectroscopic methods in solution at room temperature. In addition, theoretical studies were performed to facilitate the interpretation of the experimental results and also to simulate the reaction pathway to obtain a better understanding of the reaction mechanism. The main finding of this work is that photodehydration of 1 takes place in an ultrafast adiabatic photochemical reaction without any clear intermediate, delivering quinone methide (QM) in the excited state. Upon photoexcitation to a higher vibrational level of the singlet excited state, 1 undergoes vibrational relaxation leading to two photochemical pathways, one by which synchronous elimination of H2O gives QM 2 in its S1 state and the other by which homolytic cleavage of the phenolic O−H bond produces a phenoxyl radical (S0). Both are ultrafast processes that occur within a picosecond. The excited state of QM 2 (S1) probably deactivates to S0 through a conical intersection to give QM 2 (S0), which subsequently delivers benzoxete 4. Elucidation of the reaction mechanisms for the photodehydration of phenols by which QMs are formed is important to tune the reactivity of QMs with DNA and proteins for the potential application of QMs in medicine as therapeutic agents.
Unraveling the Mechanism of 1,3‐Diyne Cross‐Metathesis Catalyzed by Silanolate‐Supported Tungsten Alkylidyne Complexes
Authors: Schnabel Tobias M. , Melcher Daniel , Brandhorst Kai , Bockfeld Dirk , Tamm Matthias 
Published: April 2018

AbstractThe benzylidyne complex [PhC≡W{OSi(OtBu)3}3] (1) catalyzed the cross‐metathesis between 1,4‐bis(trimethylsilyl)‐1,3‐butadiyne (2) and symmetrical 1,3‐diynes (3) efficiently, which gave access to TMS‐capped 1,3‐diynes RC≡C−C≡CSiMe3 (4). Diyne cross‐metathesis (DYCM) studies with 13C‐labeled diyne PhC≡13C−13C≡CPh (3*) revealed that this reaction proceeds through reversible carbon–carbon triple‐bond cleavage and formation according to the conventional mechanism of alkyne metathesis. The reaction between 1 and 3* afforded the 3‐phenylpropynylidyne complex PhC≡13C−13C≡W{OSi(OtBu)3}3] (5*), indicating that alkynylalkylidyne complexes are likely to act as catalytically active species. Attempts to isolate 5* from mixtures of 1 and 3* afforded crystals of the ditungsten 2‐butyne‐1,4‐diylidyne complex [(tBuO)3SiO}3W≡13C−13C≡13C−13C≡W{OSi(OtBu)3}3] (6*), which was additionally characterized by X‐ray diffraction analysis. Depolymerization‐macrocyclization of a carbazole‐butadiyne polymer, obtained from 3,6‐diethynyl‐9‐dodecylcarbazole (7) under copper‐catalyzed Hay coupling conditions, was also efficiently catalyzed by 1 and afforded a mixture of mono‐, diyne‐ and triyne‐containing tetrameric macrocycles, revealing that diyne disproportionation into monoynes and triynes occurs as a slow side reaction that interferes with a high diyne metathesis selectivity. Potential catalytic pathways were studied by means of quantum‐chemical calculations, and kinetic studies were performed to substantiate an α,α‐mechanism for the catalytic diyne metathesis reaction, which involves intermediate alkynylalkylidyne and α,α′‐dialkynylmetallacyclobutadiene intermediates.
Treatment in a preventive cardiology clinic utilizing advanced practice providers effectively closes atherosclerotic cardiovascular disease risk‐management gaps among a primary‐prevention population compared with a propensity‐matched primary‐care cohort: A team‐based care model and its impact on lipid and blood pressure management
Authors: Fentanes Emilio , Vande Hei Anthony G. , Holuby R. Scott , Suarez Norma , Slim Yousif , Slim Jennifer N. , Slim Ahmad M. , Thomas Dustin 
Published: April 2018

BackgroundAdvanced practice providers (APPs) can fill care gaps created by physician shortages and improve adherence/compliance with preventive ASCVD interventions.HypothesisAPPs utilizing guideline‐based algorithms will more frequently escalate ASCVD risk factor therapies.MethodsWe retrospectively reviewed data on 595 patients enrolled in a preventive cardiology clinic (PCC) utilizing APPs compared with a propensity‐matched cohort (PMC) of 595 patients enrolled in primary‐care clinics alone. PCC patients were risk‐stratified using Framingham Risk Score (FRS) and coronary artery calcium scoring (CACS).ResultsBaseline demographics were balanced between the groups. CACS was more commonly obtained in PCC patients (P < 0.001), resulting in reclassification of 30.6% patients to a higher risk category, including statin therapy in 26.6% of low‐FRS PCC patients with CACS ≥75th MESA percentile. Aspirin initiation was higher for high and intermediate FRS patients in the PCC (P < 0.001). Post‐intervention mean LDL‐C, non–HDL‐C, and triglycerides (all P < 0.05) were lower in the PCC group. Compliance with appropriate lipid treatment was higher in intermediate to high FRS patients (P = 0.004) in the PCC group. Aggressive LDL‐C and non–HDL‐C treatment goals (<70 mg/dL, P = 0.005 and < 130 mg/dL, P < 0.001, respectively), were more commonly achieved in high‐FRS PCC patients. Median post‐intervention SBP was lower among intermediate and low FRS patients (P = 0.001 and P < 0.001, respectively). Cumulatively, this resulted in a reduction in median post‐intervention PCC FRS across all initial FRS risk categories (P < 0.001 for all).ConclusionsAPPs within a PCC effectively risk‐stratify and aggressively manage ASCVD risk factors, resulting in a reduction in post‐intervention FRS.
Patient views and correlates of radiotherapy omission in a population‐based sample of older women with favorable‐prognosis breast cancer
Authors: Shumway Dean A. , Griffith Kent A. , Hawley Sarah T. , Wallner Lauren P. , Ward Kevin C. , Hamilton Ann S. , Morrow Monica , Katz Steven J. , Jagsi Reshma 
Published: April 2018

BACKGROUNDThe omission of radiotherapy (RT) after lumpectomy is a reasonable option for many older women with favorable‐prognosis breast cancer. In the current study, we sought to evaluate patient perspectives regarding decision making about RT.METHODSWomen aged 65 to 79 years with AJCC 7th edition stage I and II breast cancer who were reported to the Georgia and Los Angeles County Surveillance, Epidemiology, and End Results registries were surveyed (response rate, 70%) regarding RT decisions, the rationale for omitting RT, decision‐making values, and understanding of disease recurrence risk. We also surveyed their corresponding surgeons (response rate, 77%). Patient characteristics associated with the omission of RT were evaluated using multilevel, multivariable logistic regression, accounting for patient clustering within surgeons.RESULTSOf 999 patients, 135 omitted RT (14%). Older age, lower tumor grade, and having estrogen receptor‐positive disease each were found to be strongly associated with omission of RT in multivariable analyses, whereas the number of comorbidities was not. Non‐English speakers were more likely to omit RT (adjusted odds ratio, 5.9; 95% confidence interval, 1.4‐24.5). The most commonly reported reasons for RT omission were that a physician advised the patient that it was not needed (54% of patients who omitted RT) and patient choice (41%). Risk of local disease recurrence was overestimated by all patients: by approximately 2‐fold among those who omitted RT and by approximately 8‐fold among those who received RT. The risk of distant disease recurrence was overestimated by approximately 3‐fold on average.CONCLUSIONSTo some extent, decisions regarding RT omission are appropriately influenced by patient age, tumor grade, and estrogen receptor status, but do not appear to be optimally tailored according to competing comorbidities. Many women who are candidates for RT omission overestimate their risk of disease recurrence. Cancer 2018;124:2714‐2723. © 2018 American Cancer Society
Retracted: Development and validation of algorithms to differentiate ductal carcinoma in situ from invasive breast cancer within administrative claims data
Authors: Hirth Jacqueline M. , Hatch Sandra S. , Lin Yu‐Li , Giordano Sharon H. , Silva H. Colleen , Kuo Yong‐Fang 
Published: April 2018

BackgroundOvertreatment is a common concern for patients with ductal carcinoma in situ (DCIS), but this entity is difficult to distinguish from invasive breast cancers in administrative claims data sets because DCIS often is coded as invasive breast cancer. Therefore, the authors developed and validated algorithms to select DCIS cases from administrative claims data to enable outcomes research in this type of data.MethodsThis retrospective cohort using invasive breast cancer and DCIS cases included women aged 66 to 70 years in the 2004 through 2011 Texas Cancer Registry (TCR) data linked to Medicare administrative claims data. TCR records were used as “gold” standards to evaluate the sensitivity, specificity, and positive predictive value (PPV) of 2 algorithms. Women with a biopsy enrolled in Medicare parts A and B at 12 months before and 6 months after their first biopsy without a second incident diagnosis of DCIS or invasive breast cancer within 12 months in the TCR were included. Women in 2010 Medicare data were selected to test the algorithms in a general sample.ResultsIn the TCR data set, a total of 6907 cases met inclusion criteria, with 1244 DCIS cases. The first algorithm had a sensitivity of 79%, a specificity of 89%, and a PPV of 62%. The second algorithm had a sensitivity of 50%, a specificity of 97%. and a PPV of 77%. Among women in the general sample, the specificity was high and the sensitivity was similar for both algorithms. However, the PPV was approximately 6% to 7% lower.ConclusionsDCIS frequently is miscoded as invasive breast cancer, and thus the proposed algorithms are useful to examine DCIS outcomes using data sets not linked to cancer registries. Cancer 2018;124:2815‐2823. © 2018 American Cancer Society
Risk factors for hepatocellular carcinoma by age, sex, and liver disorder status: A prospective cohort study in Korea
Authors: Yi Sang‐Wook , Choi Ja‐Sung , Yi Jee‐Jeon , Lee Yong‐ho , Han Ki Jun 
Published: April 2018

BACKGROUNDTo the authors' knowledge, relatively little is known regarding the interaction of risk factors for hepatocellular carcinoma (HCC) with age, sex, and liver disorder status.METHODSThe authors followed 504,646 Korean patients aged 40 to 80 years who underwent routine health checkups between 2002 and 2003 until 2013 via linkage to national hospital discharge records.RESULTSHCC occurred in 2744 individuals. In the sex‐adjusted and age‐adjusted analysis, cirrhosis increased the incidence of HCC by 42‐fold, followed by hepatitis B virus (21‐fold), hepatitis C virus (HCV; 19‐fold), male sex (4.3‐fold), and each 5‐year age increment (1.24‐fold). In the multivariable adjusted analysis, diabetes increased the risk of HCC by 80%, alcohol consumption ≥80 g/day increased the risk by 75%, alcohol consumption of 40 to 79 g/day increased the risk by 37%, and being a current smoker increased the risk by 25%. The multivariable adjusted hazard ratios of male sex and HCV were 6.27 and 5.72, respectively, at age <50 years, but were 2.09 and 22.51, respectively, at age ≥70 years. Each 20 g/day of alcohol consumption increased the risk of HCC by 6% (P = .11), 8% (P = .02), 16% (P<.001), and 30% (P<.001), respectively, in individuals aged <50 years, 50 to 59 years, 60 to 69 years, and 70 to 80 years. In individuals without a liver disorder, body mass index was found to be positively associated with HCC, whereas patients with a liver disorder demonstrated an inverse association. Women had higher adjusted hazard ratios associated with age and cirrhosis compared with men.CONCLUSIONSWith advancing age, the effects of alcohol use and HCV on the development of HCC become stronger, whereas the effect of male sex weakens. Lifetime moderate alcohol consumption may cause HCC in the elderly. Smoking increases the risk of HCC irrespective of viral hepatitis, and diabetes increases the risk of HCC independent of cirrhosis. Cancer 2018;124:2748‐2757. © 2018 American Cancer Society
A soft cooperative spectrum sensing in the presence of most destructive smart PUEA using energy detector
Authors: Emami Mohammad , Zarrabi Houman , Jabbarpour Mohammad Reza , Sadat Taheri Masumeh , Jung Jason J. 
Published: April 2018

SummaryRecently, the growth of Internet of Things (IoT) and its remarkable impacts on human well‐being life style are deniable. On the connectivity side, IoT is highly related to Wireless Sensor Network (WSN) concept. The key elements include the data, which is machine‐produced, specifically by sensors, and the data communication through connectivity technologies. On the security side, primary user emulation attack (PUE) is one of the well‐defined attacks in cognitive radio (CR)–based WSN. Here, we investigate a smart primary user emulation attacker that has the most destructive effect on the spectrum sensing unit of cognitive radio users. To deal with this attack, a soft cooperative spectrum sensing using an energy detector is proposed. In the proposed method, the values of sensing information of each secondary user are sent to a fusion center. Once the values are received, they will be combined with some appropriate coefficients in order to minimize spectrum sensing probability of error for a given probability of false alarm. The coefficients are the variables of a constrained optimization problem. Based on simulation results, our method has a lower error probability in spectrum sensing in comparison to hard combination schemes (eg, OR rule) and soft combination schemes (eg, CSINR method).
Molecular Dynamics Analysis of Charge Transport in Ionic‐Liquid Electrolytes Containing Added Salt with Mono, Di, and Trivalent Metal Cations
Authors: Vicent‐Luna José Manuel , Azaceta Eneko , Hamad Said , Ortiz‐Roldán José Manuel , Tena‐Zaera Ramón , Calero Sofía , Anta Juan Antonio 
Published: April 2018

AbstractAmong many other applications, room‐temperature ionic liquids (ILs) are used as electrolytes for storage and energy‐conversion devices. In this work, we investigate, at the microscopic level, the structural and dynamical properties of 1‐methyl‐1‐butyl‐pyrrolidinium bis(trifluoromethanesulfonyl) imide [C4PYR]+[Tf2N]− IL‐based electrolytes for metal‐ion batteries. We carried out molecular dynamics simulations of electrolytes mainly composed of [C4PYR]+[Tf2N]− IL with the addition of Mn+‐[Tf2N]− metal salts (M=Li+, Na+, Ni2+, Zn2+, Co2+, Cd2+, and Al3+, n=1, 2, and 3) dissolved in the IL. The addition of low salt concentrations lowers the charge transport and conductivity of the electrolytes. This effect is due to the strong interaction of the metal cations with the [Tf2N]− anions, which allows for molecular aggregation between them. We analyze how the conformation of the [Tf2N]− anions surrounding the metal cations determine the charge‐transport properties of the electrolyte. We found two main conformations based on the size and charge of the metal cation: monodentate and bidentate (number of oxygen atoms of the anion pointing to the metal atoms). The microscopic local structure of the Mn+‐[Tf2N]− aggregates influences the microscopic charge transport as well as the macroscopic conductivity of the total electrolyte.
Dynamic model development and control for multiple‐output flyback converters in DCM and CCM
Authors: Delavaripour Hossein , Mirzaeian Dehkordi Behzad , Adib Ehsan , Abootorabi Zarchi Hossein 
Published: April 2018

SummaryMultiple‐output flyback converters are widely used in switching power supplies due to their low component count and cost‐effective structure. The main problem of this structure is how to balance output voltages in different load conditions. This paper proposes a new approach for single‐input multiple‐output flyback converters operating in DCM and CCM by a small‐signal averaged model. The averaged model is derived by presenting the piecewise‐linear waveform for the inductor currents inside the converter. In DCM, the magnetizing current and currents through the output windings reach zero when the switch is turned off. In CCM, the magnetizing current of the converter is continuous over a switching interval and this possibility exists that only some of the output diodes completely conduct when the switch is off. The proposed model of the converter can be used in a wide range of operations within identical and non‐identical loading conditions. Using a laboratory prototype, several case studies and input‐to‐output transfer functions are considered to verify the proposed model. The controller design is performed for the both CCM and DCM, and then dynamic characteristics of the overall system are evaluated.
Beta cell stress in a 4‐year follow‐up of patients with type 2 diabetes: A longitudinal analysis of the BetaDecline Study
Authors: Russo Giuseppina T. , Giorda Carlo B. , Cercone Stefania , De Cosmo Salvatore , Nicolucci Antonio , Cucinotta Domenico ,   the BetaDecline Study Group
Published: April 2018

AbstractBackgroundType 2 diabetes mellitus (T2DM) is associated with a progressive deterioration in beta cell function and loss of glycaemic control. Clinical predictors of beta cell failure are needed to guide appropriate therapy.MethodsA prospective evaluation of a large set of potential predictors of beta cell stress, measured as change in the proinsulin/insulin (PI/I) ratio, was conducted in a cohort of 235 outpatients with T2DM on stable treatment with oral hypoglycaemic agents or diet followed up for ~4 years (median value 3.9 years; interquartile range 3.8‐4.1 years).ResultsOverall, metabolic control deteriorated over time, with a significant increase in glycated haemoglobin (HbA1c; P < .0001), proinsulin (P < .0001), and PI/I ratio (P = .001), without significant changes in the homeostatic model assessment of insulin resistance. Multivariate regression analysis showed that for each 1% (10.9 mmol/mol) increase from baseline in HbA1c, the risk of beta cell stress increased by 3.8 times; for each 1% (10.9 mmol/mol) incremental increase in HbA1c during the study, risk of beta cell stress increased by 2.25 times that at baseline. By contrast, baseline anthropometric and clinical variables, lipid profile, inflammatory markers (PCR, IL‐6), non‐esterified fatty acids, and current therapies did not independently influence PI/I ratio variation during follow‐up.ConclusionsIn this cohort of patients with T2DM, beta cell function progressively deteriorated despite current therapies. Among a large set of clinical and biochemical predictors, only baseline HbA1c levels and their deterioration overtime were associated with higher beta cell stress over time.