bluuebunny/crossref_metadata_2025 huggingface dataset:
Supporting Mentoring Relationships of Youth in Foster Care: Do Program Practices Predict Match Length?
Authors: Stelter Rebecca L. , Kupersmidt Janis B. , Stump Kathryn N.
Published: April 2018

Implementation of research‐ and safety‐based program practices enhance the longevity of mentoring relationships, in general; however, little is known about how mentoring programs might support the relationships of mentees in foster care. Benchmark program practices and Standards in the Elements of Effective Practice for Mentoring, 3rd Edition (MENTOR, 2009) were assessed in the current study as predictors of match longevity. Secondary data analyses were conducted on a national agency information management database from 216 Big Brothers Big Sisters agencies serving 641 youth in foster care and 70,067 youth not in care from across the United States (Mean = 11.59 years old at the beginning of their matches) in one‐to‐one, community‐based (55.06%) and school‐ or site‐based (44.94%) matches. Mentees in foster care had shorter matches and matches that were more likely to close prematurely than mentees who were not in foster care. Agency leaders from 32 programs completed a web‐based survey describing their policies and practices. The sum total numbers of Benchmark program practices and Standards were associated with match length for 208 mentees in foster care; however, neither predicted premature match closure. Results are discussed in terms of how mentoring programs and their staff can support the mentoring relationships of high‐risk youth in foster care.
Intermolecular Electronic Communication in Tetrathiafulvalene Derivatives with Hydrogen‐Bonding Amide Units
Authors: Kaneko Ryuji , Wu Guohua , Sugawa Kosuke , Otsuki Joe
Published: April 2018

As a basis for the design of electroactive materials, mono‐ and bis‐tetrathiafulvalene (TTF) derivatives with one and two amide units were prepared to investigate how hydrogen bonding induces electronic communication. The bis‐TTF compound exhibited a mixed‐valence state as a result of electronic interactions among the TTF units. Comparison with non‐hydrogen‐bonding N‐methylated analogues indicated that the electronic interaction observed occurs between intermolecular TTF units owing to the formation of supramolecular assemblies induced by hydrogen bonds.
Chiral Atropisomeric Indenocorannulene Bowls: Critique of the Cahn–Ingold–Prelog Conception of Molecular Chirality
Authors: Wang Yujia , Allemann Oliver , Balaban T. Silviu , Vanthuyne Nicolas , Linden Anthony , Baldridge Kim K. , Siegel Jay S.
Published: April 2018

Chiral corannulenes abound, but suffer generally from configurational lability associated with bowl‐to‐bowl inversion, thus obviating questions of stereogenicity and stereoelement construction. In contrast, peri‐annulated corannulenes show greatly increased barriers for bowl‐to‐bowl inversion; specifically indenocorannulenes invert on a time scale too slow to observe by normal NMR methods and raise the possibility of creating chiral atropisomeric bowl‐shaped aromatics. Two methods for preparing indenocorannulene from simple 2‐haloarylcorannulenes—silyl cation C–F activation, and Pd‐mediated C–Cl activation[5]—enable the synthesis of an array of such chiral atropisomeric indenocorannulenes. Resolution of the enantiomers by high‐performance liquid chromatography over chiral support phases motivates the study of chiroptical properties, the assignment of absolute “Cartesian” configuration, and the assessment of configurational stability. These studies bring into question any systematic assignment of nontrivial stereoelements (i.e. not the molecule in its entirety) and refute any assertion of congruence between “Cahn–Ingold–Prelog elements” and the physical or “Cartesian” basis of chirality.
Spatially Confined Assembly of Monodisperse Ruthenium Nanoclusters in a Hierarchically Ordered Carbon Electrode for Efficient Hydrogen Evolution
Authors: Wang Zhong‐Li , Sun Keju , Henzie Joel , Hao Xianfeng , Li Cuiling , Takei Toshiaki , Kang Yong‐Mook , Yamauchi Yusuke
Published: April 2018

The redox units of polyaniline (PAni) are used cooperatively, and in situ, to assemble ruthenium (Ru) nanoclusters in a hierarchically ordered carbon electrode. The oxidized quinonoid imine (QI) units in PAni bond Ru complex ions selectively, whereas reduced benzenoid amine (BA) units cannot. By electrochemically tuning the ratio of QI to BA, Ru complexes are spatially confined in the outer layer of hierarchical PAni frameworks. Carbonization of Ru‐PAni hybrids induces nucleation on the outer surface of the carbon support, generating nearly monodisperse Ru nanoclusters. The optimized catalyst has a low loading of approximately 2 wt % Ru, but exhibits a mass activity for the hydrogen evolution reaction that is about 6.8 times better than commercial 20 wt % Pt/C catalyst.
Generierung von Aryl‐ und Heteroarylmagnesium‐Reagenzien in Toluol mittels Br/Mg‐ oder Cl/Mg‐Austausch
Authors: Ziegler Dorothée S. , Karaghiosoff Konstantin , Knochel Paul
Published: April 2018

Das Alkylmagnesiumalkoxid sBuMgOR⋅LiOR (R=2‐Ethylhexyl), das als eine 1.5 m Lösung in Toluol hergestellt wurde, ermöglicht einen sehr schnellen Br/Mg‐Austausch mit Aryl‐ und Heteroarylbromiden, wobei Aryl‐ und Heteroarylalkoxide (ArMgOR⋅LiOR) in Toluol gebildet werden. Diese Grignard‐Reagenzien reagieren mit einer Vielzahl an Elektrophilen, einschließlich Aldehyden, Ketonen, Iminen, Allylbromiden, Acylchloriden, Epoxiden und Aziridinen in guten Ausbeuten. Bemerkenswerterweise ermöglicht das ähnliche Reagenz sBu2Mg⋅2 LiOR einen Cl/Mg‐Austausch mit verschiedenen elektronenreichen Arylchloriden in Toluol, wobei Diorganomagnesiumspezies des Typs Ar2Mg⋅2 LiOR gebildet werden, die gut mit Aldehyden und Allylbromiden reagieren.
Rational Fabrication of Anti‐Freezing, Non‐Drying Tough Organohydrogels by One‐Pot Solvent Displacement
Authors: Chen Fan , Zhou Dan , Wang Jiahui , Li Tianzhen , Zhou Xiaohu , Gan Tiansheng , Handschuh‐Wang Stephan , Zhou Xuechang
Published: April 2018

Tough hydrogels, polymeric network structures with excellent mechanical properties (such as high stretchability and toughness), are emerging soft materials. Despite their remarkably mechanical features, tough hydrogels exhibit two flaws (freezing around the icing temperatures of water and drying under arid conditions). Inspired by cryoprotectants (CPAs) used in the inhibition of the icing of water in biological samples, a versatile and straightforward method is reported to fabricate extreme anti‐freezing, non‐drying CPA‐based organohydrogels with long‐term stability by partially displacing water molecules within the pre‐fabricated hydrogels. CPA‐based Ca‐alginate/polyacrylamide (PAAm) tough hydrogels were successfully fabricated with glycerol, glycol, and sorbitol. The CPA‐based organohydrogels remain unfrozen and mechanically flexible even up to −70 °C and are stable under ambient conditions or even vacuum.
Creating a Low‐Potential Redox Polymer for Efficient Electroenzymatic CO2 Reduction
Authors: Yuan Mengwei , Sahin Selmihan , Cai Rong , Abdellaoui Sofiene , Hickey David P. , Minteer Shelley D. , Milton Ross D.
Published: April 2018

Increasing greenhouse gas emissions have resulted in greater motivation to find novel carbon dioxide (CO2) reduction technologies, where the reduction of CO2 to valuable chemical commodities is desirable. Molybdenum‐dependent formate dehydrogenase (Mo‐FDH) from Escherichia coli is a metalloenzyme that is able to interconvert formate and CO2. We describe a low‐potential redox polymer, synthesized by a facile method, that contains cobaltocene (grafted to poly(allylamine), Cc‐PAA) to simultaneously mediate electrons to Mo‐FDH and immobilize Mo‐FDH at the surface of a carbon electrode. The resulting bioelectrode reduces CO2 to formate with a high Faradaic efficiency of 99±5 % at a mild applied potential of −0.66 V vs. SHE.
Stishovite's Relative: A Post‐Coesite Form of Phosphorus Oxonitride
Authors: Vogel Sebastian , Baumann Dominik , Niklaus Robin , Bykova Elena , Bykov Maxim , Dubrovinskaia Natalia , Dubrovinsky Leonid , Schnick Wolfgang
Published: April 2018

Phosphorus oxonitride (PON) is isoelectronic with SiO2 and may exhibit a similar broad spectrum of intriguing properties as silica. However, PON has only been sparsely investigated under high‐pressure conditions and there has been no evidence on a PON polymorph with a coordination number of P greater than 4. Herein, we report a post‐coesite (pc) PON polymorph exhibiting a stishovite‐related structure with P in a (5+1) coordination. The pc‐PON was synthesized using the multianvil technique and characterized by powder X‐ray diffraction, solid‐state NMR spectroscopy, TEM measurements and in situ synchrotron X‐ray diffraction in diamond anvil cells. The structure model was verified by single‐crystal X‐ray diffraction at 1.8 GPa and the isothermal bulk modulus of pc‐PON was determined to K0=163(2) GPa. Moreover, an orthorhombic PON polymorph (o‐PON) was observed under high‐pressure conditions and corroborated as the stable modification at pressures above 17 GPa by DFT calculations.
Generation of Aryl and Heteroaryl Magnesium Reagents in Toluene by Br/Mg or Cl/Mg Exchange
Authors: Ziegler Dorothée S. , Karaghiosoff Konstantin , Knochel Paul
Published: April 2018

The alkylmagnesium alkoxide sBuMgOR⋅LiOR (R=2‐ethylhexyl), which was prepared as a 1.5 m solution in toluene, undergoes very fast Br/Mg exchange with aryl and heteroaryl bromides, producing aryl and heteroaryl magnesium alkoxides (ArMgOR⋅LiOR) in toluene. These Grignard reagents react with a broad range of electrophiles, including aldehydes, ketones, allyl bromides, acyl chlorides, epoxides, and aziridines, in good yields. Remarkably, the related reagent sBu2Mg⋅2 LiOR (R=2‐ethylhexyl) undergoes Cl/Mg exchange with various electron‐rich aryl chlorides in toluene, producing diorganomagnesium species of type Ar2Mg⋅2 LiOR, which react well with aldehydes and allyl bromides.
Investigation on hydrates blockage and restart process mechanisms of CO2 hydrate slurry flow
Authors: Shi Bo‐Hui , Ding Lin , Li Wen‐Qing , Lv Xiao‐Fang , Liu Yang , Song Shang‐Fei , Ruan Chao‐Yu , Wu Hai‐Hao , Wang Wei , Gong Jing
Published: April 2018

Being an alternative environment‐friendly fluid for the refrigeration process, CO2 hydrate slurry is undesired to result in hydrate blocking in the system. A series of water‐based CO2 hydrate slurry experiments were conducted to investigate hydrate blockages in a high‐pressure flow loop. Blocking would occur soon after CO2 hydrate formation onset. Rapid restart process after the first blocking was found to have serious consequence by inducing a fast hydrate regrowth and an irreversible secondary blocking. The mechanisms of the first blocking and the secondary blocking after the restart process were proposed, based on the observed phenomena and the particle chord length distribution data recorded by focused beam reflectance measurement probe. The influences of the initial flow rate on the supercooling, the induction time, the restart time, and the required time for the secondary blocking after the restart process were analyzed. The understanding on the blocking and restart process mechanisms of CO2 hydrate slurry is important not only in the development of hydrate‐based refrigeration system but also in the field of flow assurance in the oil and gas pipeline or for other applications such as the replacement of methane by CO2 in the naturally occurring hydrate exploration.
Biological evaluation of selected 3,4‐dihydro‐2(1H)‐quinoxalinones and 3,4‐dihydro‐1,4‐benzoxazin‐2‐ones: Molecular docking study
Authors: Petronijević Jelena , Janković Nenad , Stanojković Tatjana P. , Joksimović Nenad , Grozdanić Nađa Đ. , Vraneš Milan , Tot Aleksandar , Bugarčić Zorica
Published: April 2018

In order to investigate new potential therapeutically active agents, we investigated the biological properties of two small libraries of quinoxalinones and 1,4‐benzoxazin‐2‐ones. The results obtained showed that compounds 5, 9–11 have good cytotoxic activity against HeLa cells where the lowest IC50 value (10.46 ± 0.82 μM/mL) was measured for compound 10. Additionally, the most active compounds (5, 9–11) showed much better selectivity for MRC‐5 cells (up to 17.4) compared to cisplatin. In vitro evaluation of the inhibition of the enzyme α‐glucosidase showed that compounds 10 and 11 exert significant inhibition of the enzyme at 52.54 ± 0.09 and 40.09 ± 0.49 μM, respectively. Competitive experiments with ethidium bromide (EB) indicated that all tested compounds have affinity to displace EB from the EB‐DNA complex through intercalation, suggesting good competition with EB (Ksv = (3.1 ± 0.2), (5.1 ± 0.1), (5.6 ± 0.2), and (6.3 ± 0.2) × 103 M−1). A molecular docking study was also performed to better understand the binding modes and to conclude the structure–activity relationships of the synthesized compounds.
Design and synthesis of novel annulated thienopyrimidines as phosphodiesterase 5 (PDE5) inhibitors
Authors: El‐Sharkawy Lina Y. , El‐Sakhawy Rowaida A. , Abdel‐Halim Mohammad , Lee Kevin , Piazza Gary A. , Ducho Christian , Hartmann Rolf W. , Abadi Ashraf H.
Published: April 2018

Novel cycloalkene‐fused thienopyrimidine analogues with enhanced phosphodiesterase 5 (PDE5) inhibitory properties are presented. The structure of the reported scaffold was modulated through variation of the terminal cycloalkene ring size, as well as by varying the substituents at position 4 through the attachment of different groups including aniline, benzylamine, cyclohexylethylamine, methyl/acetyl/aryl piperazines, and aryl hydrazones. Compound 15Y with a benzylamine substituent and cycloheptene as terminal ring showed the highest PDE5 inhibitory activity with an IC50 value as low as 190 nM and with good selectivity versus PDE7 and PDE9.
Facile N‐Alkylation/N′‐Arylation Process: A Direct Approach to Aromatic Aminoalkyl Amines
Authors: Zhu Qiming , Chen Mingwei , Hu Jinyu , Yang Luyi
Published: April 2018

An intriguing C−N transformation involving a catalyst‐free N‐alkylation/N′‐arylation process in a multicomponent reaction with secondary amines, cyclic tertiary amines and electron‐deficient aryl halides has been described. In this case, the N‐alkylation of secondary amines, utilizing cyclic tertiary amines as alkyl group sources, is enabled by a facile C−N cleavage. Such an operationally simple method could facilitate access to aromatic aminoalkyl amines, nitrogen‐containing bioactive molecules, in good to excellent yields.
Period changes in the RR Lyrae stars of NGC 6171 (M107)
Authors: Arellano Ferro A. , Rosenzweig P. , Luna A. , Deras D. , Muneer S. , Giridhar S. , Michel R.
Published: April 2018

Based on photometric data obtained between 1935 and 2017, O − C diagrams were built for 22 RR Lyrae stars in the globular cluster NGC 6171, leading to the discovery of secular period changes in four variables for which we have calculated period change rates β. In contrast, we find that 82% of the sample stars have stable periods over the last 82 years. For the stable‐period stars, the whole database has been employed to refine their periods. Among the period‐changing stars, three (V10, V12, and V16) have decreasing periods that are larger than expected from stellar evolution. Despite these individual cases of significant period change rate, the global average of the measured period changes in the cluster is basically zero, in consonance with theoretical predictions for clusters with redder horizontal branches. The hitherto unpublished observations, now brought into public domain, are employed to calculate a set of times of maximum light, which is used in the present analysis.
Hyperactive cyclic motor activity in the distal colon after colonic surgery as defined by high-resolution colonic manometry
Authors: Vather R , O'Grady G , Lin A Y , Du P , Wells C I , Rowbotham D , Arkwright J , Cheng L K , Dinning P G , Bissett I P
Published: April 2018

Background

Recovery after colonic surgery is invariably delayed by disturbed gut motility. It is commonly assumed that colonic motility becomes quiescent after surgery, but this hypothesis has not been evaluated rigorously. This study quantified colonic motility through the early postoperative period using high-resolution colonic manometry.

Methods

Fibre-optic colonic manometry was performed continuously before, during and after surgery in the left colon and rectum of patients undergoing right hemicolectomy, and in healthy controls. Motor events were characterized by pattern, frequency, direction, velocity, amplitude and distance propagated.

Results

Eight patients undergoing hemicolectomy and nine healthy controls were included in the study. Colonic motility became markedly hyperactive in all operated patients, consistently dominated by cyclic motor patterns. Onset of cyclic motor patterns began to a minor extent before operation, occurring with increasing intensity nearer the time of surgery; the mean(s.d.) active duration was 12(7) per cent over 3 h before operation and 43(17) per cent within 1 h before surgery (P = 0.024); in fasted controls it was 2(4) per cent (P < 0·001). After surgery, cyclic motor patterns increased markedly in extent and intensity, becoming nearly continuous (active duration 94(13) per cent; P < 0·001), with peak frequency 2–4 cycles per min in the sigmoid colon. This postoperative cyclic pattern was substantially more prominent than in non-operative controls, including in the fed state (active duration 27(20) per cent; P < 0·001), and also showed higher antegrade velocity (P < 0·001).

Conclusion

Distal gut motility becomes markedly hyperactive with colonic surgery, dominated by cyclic motor patterns. This hyperactivity likely represents a novel pathophysiological aspect of the surgical stress response. Hyperactive motility may contribute to gut dysfunction after surgery, potentially offering a new therapeutic target to enhance recovery.
Trends in use of lymphadenectomy in surgery with curative intent for intrahepatic cholangiocarcinoma
Authors: Zhang X -F , Chakedis J , Bagante F , Chen Q , Beal E W , Lv Y , Weiss M , Popescu I , Marques H P , Aldrighetti L , Maithel S K , Pulitano C , Bauer T W , Shen F , Poultsides G A , Soubrane O , Martel G , Groot Koerkamp B , Guglielmi A , Itaru E , Pawlik T M
Published: April 2018

Background

The role of routine lymph node dissection (LND) in the surgical treatment of intrahepatic cholangiocarcinoma (ICC) remains controversial. The objective of this study was to investigate the trends of LND use in the surgical treatment of ICC.

Methods

Patients undergoing curative intent resection for ICC in 2000–2015 were identified from an international multi-institutional database. Use of lymphadenectomy was evaluated over time and by geographical region (West versus East); LND use and final nodal status were analysed relative to AJCC T categories.

Results

Among the 1084 patients identified, half (535, 49·4 per cent) underwent concomitant hepatic resection and LND. Between 2000 and 2015, the proportion of patients undergoing LND for ICC nearly doubled: 44·4 per cent in 2000 versus 81·5 per cent in 2015 (P < 0·001). Use of LND increased over time among both Eastern and Western centres. The odds of LND was associated with the time period of surgery and the extent of the tumour/T status (referent T1a: OR 2·43 for T2, P = 0·001; OR 2·13 for T3, P = 0·016). Among the 535 patients who had LND, lymph node metastasis (LNM) was noted in 209 (39·1 per cent). Specifically, the incidence of LNM was 24 per cent in T1a disease, 22 per cent in T1b, 42·9 per cent in T2, 48 per cent in T3 and 66 per cent in T4 (P < 0·001). AJCC T3 and T4 categories, harvesting of six or more lymph nodes, and presence of satellite lesions were independently associated with LNM.

Conclusion

The rate of LNM was high across all T categories, with one in five patients with T1 disease having nodal metastasis. The trend in increased use of LND suggests a growing adoption of AJCC recommendations in the treatment of ICC.
Fast and sensitive HPLC/UV method for cefazolin quantification in plasma and subcutaneous tissue microdialysate of humans and rodents applied to pharmacokinetic studies in obese individuals
Authors: Palma Eduardo Celia , Laureano João Victor , de Araújo Bibiana Verlindo , Meinhardt Nelson Guardiola , Stein Airton Tetelbom , Dalla Costa Teresa
Published: April 2018

Antimicrobial prophylactic dosing of morbidly obese patients may differ from normal weighted individuals owing to alterations in drug tissue distribution. Drug subcutaneous tissue distribution can be investigated by microdialysis patients and animals. The need for cefazolin prophylactic dose adjustment in obese patients remains under discussion. The paper describes the validation of an HPLC‐UV method for cefazolin quantification in plasma and microdialysate samples from clinical and pre‐clinical studies. A C18 column with an isocratic mobile phase was used for drug separation, with detection at 272 nm. Total and unbound cefazolin lower limit of quantitation was 5 μg/mL in human plasma, 2 μg/mL in rat plasma, and 0.5 and 0.025 μg/mL in human and rat microdialysate samples, respectively. The maximum intra‐ and inter‐day imprecisions were 10.7 and 8.1%, respectively. The inaccuracy was <9.7%. The limit of quantitation imprecision and inaccuracy were < 15%. Cefazolin stability in the experimental conditions was confirmed. Cefazolin plasma concentrations and subcutaneous tissue penetration were determined by microdialysis in morbidly obese patients (2 g i.v. bolus) and diet‐induced obese rats (30 mg/kg i.v. bolus) using the method. This method has the main advantages of easy plasma clean‐up and practicability and has proven to be useful in cefazolin clinical and pre‐clinical pharmacokinetic investigations.
Behavioral and neurophysiological abnormalities during cued continuous performance tasks in patients with mild traumatic brain injury
Authors: Zhao Weixiang , Wu Ruhong , Wang Suhong , Qi Haihui , Qian Yitao , Wang Suinuan
Published: April 2018

Objective

This study's aim was to investigate the features and neural mechanisms of sustained attention in patients with mild traumatic brain injury (mTBI) by comparing and analyzing neuropsychological, behavioral, event‐related potentials, and event‐related desynchronization and synchronization between mTBI patients and healthy controls.

Methods

Twenty mTBI patients with mTBI and 20 healthy controls underwent the Mini‐Mental State Examination (MMSE) and a cued continuous performance task (AX‐CPT). Neuropsychological, behavioral, and electroencephalogram (EEG) data were collected and analyzed.

Results

There were significant differences between the mTBI group and the control group in their MMSE total scores, attention, and calculation, but there were no significant differences in orientation, memory, recall, and verbal scores. There were significant differences between the mTBI group and the control group in hitting the number, reaction time, and the number of errors of omission, but there were no significant differences in the number of false errors. The amplitude of Go‐N2 and Nogo‐N2 was significantly smaller for the mTBI group than that for the control group. The amplitude of Go‐P3 was significantly smaller for the mTBI group than that for the control group, but not for the amplitude of Nogo‐P3. The Go‐αERS were significantly less for the mTBI group than for the control group during the 0–200 ms after the stimulus onset. The Go‐αERD and Nogo‐αERD were significantly less for the mTBI group than for the control group during the 600–1,000 ms after the stimulus onset. The Go‐βERS were significantly less for the mTBI group than for the control group during the 200–400 ms after the stimulus onset. There were no significant differences in the Nogo‐αERS and Nogo‐βERD/ERS between the mTBI group and the control group.

Conclusion

Patients with mTBI exhibited impairments in sustained attention and conflict monitoring, while response inhibition may have been spared.
Teaching modern power electronics—Computerized test stand design
Authors: Bonisławski Michał , Hołub Marcin
Published: April 2018

A unified, computer controlled, modern system design for power electronics experimental laboratory is presented. Proposed test stand configuration simplifies the introductory part of the lab and maximizes the time that the students can use for experimental measurements and calculations. Hardware test stands (not only simulations) have a common pre‐configuration for all exercises so that students do not need to learn the system design and measurement configuration of every particular test stand. Clear measurement setup and momentary and average electrical parameter readings are done using a computer user interface. Hardware and software protection loops are foreseen so the number of errors of the hardware during testing is minimized, simple arrangement minimizes errors during test preparation.
Understand how to manage eligibility issues for your foreign student‐athletes
Authors: O'Brien Timothy
Published: April 2018

Approximately 17,000 foreign student‐athletes participate in sports at National Collegiate Athletic Association member schools in the U.S. This means athletics departments must be as vigilant as ever in ensuring that the eligibility of each prospective international student‐athlete is clear and unassailable at the time of enrollment and throughout their attendance at the school, lest they risk potential sanctions as a result of the participation of an ineligible competitor.
Discover how the Runner Ambassador Program can create a home for international student‐athletes
Authors: Stribling Rosemary
Published: April 2018

When international student‐athletes are separated from their familiar surroundings and comforts of home, they suffer anxiety and stress, to the point of debilitation and depression. Their transition to the United States involves not only the typical academic pressures facing a first‐year college student, but they also have to manage their rigorous athletics schedules and adapt to their new identities as a temporary resident in a new country.
Was ‘qualified immunity’ sufficient to shield coach?
Authors: Gelpi Aileen
Published: April 2018

Smith Center High School student Jane Doe dated a football player in 2013. She also was on the wrestling team coached by Brock Hutchinson. In 2014, Hutchinson began asking Doe's boyfriend in the presence of his teammates about what kind of sexual acts she had performed.
Gain insight into setting clear priorities
Authors: Elfman Lois
Published: April 2018

In the world of intercollegiate athletics, there are only a handful of women who serve as athletics directors in the Power Five conferences. One of them is Jennifer Cohen, who was named AD of the University of Washington in May 2016.
siRNA Modified with 2′‐Deoxy‐2′‐C‐methylpyrimidine Nucleosides
Authors: Dellafiore María , Aviñó Anna , Alagia Adele , Montserrat Javier M. , Iribarren Adolfo M. , Eritja Ramon
Published: April 2018

(2′S)‐2′‐Deoxy‐2′‐C‐methyluridine and (2′R)‐2′‐deoxy‐2′‐C‐methyluridine were incorporated in the 3′‐overhang region of the sense and antisense strands and in positions 2 and 5 of the seed region of siRNA duplexes directed against Renilla luciferase, whereas (2′S)‐2′‐deoxy‐2′‐C‐methylcytidine was incorporated in the 6‐position of the seed region of the same constructions. A dual luciferase reporter assay in transfected HeLa cells was used as a model system to measure the IC50 values of 24 different modified duplexes. The best results were obtained by the substitution of one thymidine unit in the antisense 3′‐overhang region by (2′S)‐ or (2′R)‐2′‐deoxy‐2′‐C‐methyluridine, reducing IC50 to half of the value observed for the natural control. The selectivity of the modified siRNA was measured, it being found that modifications in positions 5 and 6 of the seed region had a positive effect on the ON/OFF activity.
6‐Minute walk test predicts prolonged hospitalization in patients undergoing transcatheter mitral valve repair by MitraClip
Authors: Saji Mike , Katz Marc R. , Ailawadi Gorav , Welch Timothy S. , Fowler Dale E. , Kennedy Jamie L.W. , Bergin James D. , Kuntjoro Ivandito , Dent John M. , Ragosta Michael , Lim D. Scott
Published: April 2018

Background

The 6‐minute walk test (6MWT) is a simple functional test that can predict exercise capacity and is widely employed to assess treatment outcomes. Although mortality with transcatheter mitral valve repair (TMVr) using the MitraClip (Abbott Vascular, Menlo Park, CA) is significantly less than for open mitral valve surgery in high‐risk patients, identifying which patient will benefit the most from TMVr remains a concern. There are limited prognostic metrics guiding patient selection and, no studies have reported relationship between prolonged hospitalization and 6MWT. This study aimed to determine if the 6MWT can predict prolonged hospitalization in patients undergoing TMVr by MitraClip.

Methods

We retrospectively reviewed 162 patients undergoing 6MWT before TMVr. Patients were divided into three groups according to the 6MWT distance (6MWTD) using the median (6MWTD ≥219 m, 6MWTD <219 m, and Unable to Walk). Multivariate logistic regression model was applied to select the demographic characteristics that were associated with the prolonged hospitalization defined as total length of stay ≥4 days in the study.

Results

We found that 6MWT (odds ratio 3.64, 95% confidence interval 2.03–6.52, P < 0.001) was independently associated with prolonged hospitalization after adjustment in multivariate analysis. Area under the curve of 6MWT for predicting prolonged hospitalization was 0.79 (95% confidence interval 0.72–0.85).

Conclusions

Our study demonstrates that 6MWT was independently associated with prolonged hospitalization in patients with TMVr, and has a good discriminatory performance for predicting prolonged hospitalization.
Quantitative Mapping of Nanoscale Chemical Dynamics in Sub‐Sampled Operando (S)TEM Images using Spatio‐Temporal Analytics
Authors: Stanfill Bryan A. , Reehl Sarah M. , Johnson Margaret C. , Browning Nigel D. , Mehdi B. Layla , Caragea Petruta C. , Bramer Lisa M.
Published: April 2018

One of the main limitations in the use of operando scanning transmission electron microscopes to study dynamic chemical processes is the effect of the electron beam on the kinetics of the reaction being observed. Here we demonstrate that a flexible Gaussian mixture model can be used to extract quantitative information directly from sub‐sampled images, that is, images in which not all the pixels in the image are illuminated with the beam. The use of this method is demonstrated on the growth of silver (Ag) nanoparticles in an aqueous solution and the charge/discharge cycle of a lithium battery. In both videos, the imaged chemical reactions can be accurately quantified for sub‐sampling levels down to 1 %. In addition, our analysis of the Ag nucleation video sheds new light on the interplay between heterogeneous and homogeneous nucleation dynamics. Performing operando imaging using a small fraction of the pixels means that the observations can significantly reduce the effect of the beam, automatically increase the imaging speed and decrease the total data transfer rate required. Such new software capabilities offer the potential to significantly widen the application of operando hardware approaches to study nanoscale dynamics in materials.
Selective Aerobic Oxidation of Alcohols with NO3− Activated Nitroxyl Radical/Manganese Catalyst System
Authors: Lagerblom Kalle , Keskiväli Juha , Parviainen Arno , Mannisto Jere , Repo Timo
Published: April 2018

A homogeneous Mn(NO3)2/2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl/2‐picolinic acid catalyst system is highly active and versatile for the selective aerobic oxidation of alcohols (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl=TEMPO, 2‐picolinic acid=PyCOOH). The catalytic method enables near quantitative conversion of various primary alcohols to the respective aldehydes using a very simple reaction setup and workup. This study presents findings on the catalyst stability and mechanisms of deactivation. The results show that NO3− plays a crucial catalytic role in the reaction as a source of oxygen activating NOx species. Yet, disproportionation of NO3− to the volatile NO2 during the reaction leads to catalyst deactivation under open air conditions. Catalyst deactivation through this route can be overcome by adding a catalytic amount of nitrate salt, for example NaNO3 into the reaction. This stabilizes the Mn(NO3)2/TEMPO/PyCOOH catalyst and enables oxidation of various primary alcohols to the respective aldehydes using low catalyst loadings under ambient conditions. Secondary alcohols can be oxidized with a modified catalyst utilizing sterically accessible nitroxyl radical 9‐azabicyclo[3.3.1]nonane N‐oxyl (ABNO) instead of TEMPO. At the end of the alcohol oxidation, pure carbonyl products and the reusable catalyst can be recovered simply by extracting with organic solvent and dilute aqueous acid, followed by evaporation of both phases.
Enhanced Activation of Coordinated Dinitrogen with p‐Block Lewis Acids
Authors: Simonneau Antoine , Etienne Michel
Published: April 2018

This Concept article highlights recent research on Lewis acid adducts of dinitrogen complexes, including our contributions. After a reminder of the early works, it is demonstrated that such kind of species offers a new platform for dinitrogen functionalization as well as valuable models for the understanding of elementary steps of (bio)catalytic cycles. When possible, parallels regarding this mode of activation from the orbital point of view are drawn between the different systems discussed herein.
Binding of Lanthanide Complexes to Histidine‐Containing Peptides Probed by Raman Optical Activity Spectroscopy
Authors: Brichtová Eva , Hudecová Jana , Vršková Nikola , Šebestík Jaroslav , Bouř Petr , Wu Tao
Published: April 2018

Lanthanide complexes are used as convenient spectroscopic probes for many biomolecules. Their binding to proteins is believed to be enhanced by the presence of histidine, but the strength of the interaction significantly varies across different systems. To understand the role of peptide length and sequence, short histidine‐containing peptides have been synthesized (His‐Gly, His‐Gly‐Gly, His‐Gly‐Gly‐Gly, Gly‐His, Gly‐His‐Gly, His‐His, and Gly‐Gly‐His) and circularly polarized luminescence (CPL) induced at the [Eu(dpa)3]3− complex has been measured by means of a Raman optical activity (ROA) spectrometer. The obtained data indicate relatively weak binding of the histidine residue to the complex, with a strong participation of other parts of the peptide. Longer peptides, low pH, and a histidine residue close to the N‐peptide terminus favor the binding. The binding strengths are approximately proportional to the CPL intensity and roughly correlate with predictions based on molecular dynamics (MD) simulations. The specificity of lanthanide binding to the peptide structure and its intense luminescence and high optical activity make the ROA/CPL technique suitable for probing secondary and tertiary structures of peptides and proteins.
Hydrogenation of Multiple Bonds by Geminal Aminoborane‐Based Frustrated Lewis Pairs
Authors: Yepes Diana , Jaque Pablo , Fernández Israel
Published: April 2018

The hydrogenation reaction of multiple bonds that is mediated by geminal aminoborane‐based frustrated Lewis pairs (FLPs) has been explored by means of density functional theory calculations. It was found that the release of the activated dihydrogen occurred in a concerted, yet highly asynchronous, manner. The physical factors that control the transformation were quantitatively described in detail by using the activation strain model of reactivity in combination with the energy decomposition analysis method. This approach suggested a cooperative double hydrogen‐transfer mechanism, which involves the initial migration of the protic (N)H followed by the nucleophilic attack of the (B)H hydride to the carbon atom of the multiple bond. The influence of both the substituents directly attached to the boron atom of the initial FLP and the nature of the multiple bond on the transformation was also investigated.
Coordination Complexes of Titanium(IV) and Indium(III) Phthalocyanines with Carbonyl‐Containing Dyes: The Formation of Singly Bonded Anionic Squarylium Dimers
Authors: Konarev Dmitri V. , Kuzmin Alexey V. , Khasanov Salavat S. , Fatalov Alexey M. , Yudanova Evgenia I. , Lyubovskaya Rimma N.
Published: April 2018

Reduction methods for the preparation of coordination complexes of titanium(IV) and indium(III) phthalocyanines (Pc) with organic dyes such as indigo, thioindigo, and squarylium dye III (SQ) have been developed, which allow one to obtain crystalline {cryptand(K+)}{(cis‐indigo‐O,O)2−TiIV(Pc2−)}(Cl−)⋅C6H4Cl2 (1), {cryptand(K+)}{(cis‐thioindigo‐O,O)2−InIII(Pc2−)}−⋅C6H4Cl2 (2), and {cryptand(K+)}{[(SQ)2‐O,O]2−InIII(Pc2−)}−⋅3.5 C6H4Cl2 (3) complexes. The formation of these complexes is accompanied by the reduction of the starting dyes to the anionic state. Transition of trans‐indigo or trans‐thioindigo to the cis conformation in 1 and 2 provides coordination of both carbonyl oxygen atoms of the dye to TiIVPc or InIIIPc. SQ is reduced to the radical anion state and forms unusual diamagnetic singly bonded (SQ−)2 dimers in 3. These dimers have two closely positioned carbonyl oxygen atoms coordinated to InIIIPc. Dianionic Pc2− macrocycles have been found in 1–3. The complexes contain two chromophore molecules at one metal center. However, their optical spectra are defined mainly by absorption bands of the metal phthalocyanines.
Rapid Electron Transfer of Stacked Heterodimers of Perylene Diimide Derivatives in a DNA Duplex
Authors: Takada Tadao , Ishino Syunya , Takata Ami , Nakamura Mitsunobu , Fujitsuka Mamoru , Majima Tetsuro , Yamana Kazushige
Published: April 2018

The preparation of homo‐ and heterocomplexes composed of the parent perylene diimide (PH) and pyrrolidine‐substituted perylene diimide (PN) in DNA and rapid electron transfer in these complexes, which has been analyzed by steady‐state fluorescence and femtosecond transient absorption measurements, have been demonstrated. The DNA molecules possessing PH and PN were prepared through a recently developed method that involved the reaction of enzymatically generated abasic sites with the amino groups of the perylene diimide molecules, through which these molecules can be incorporated as base surrogates within the DNA base stack. Melting temperature analysis showed that the PH and PN monomers, and their homo‐ and heterodimers, contribute to the stabilization of the DNA duplex, and is comparable to that of natural base pairs. Fluorescence measurements showed that PH in a single‐stranded oligopyrimidine showed a strong fluorescence, whereas the fluorescence of PH was completely quenched upon pairing with PN (PH/PN) through duplex formation. The transient absorption measurements showed that a rapid electron‐transfer reaction in the stacked PH/PN heterodimer occurred on a sub‐picosecond timescale, which allowed highly efficient fluorescence quenching. The PH/PN pair, which served as a fluorophore and quencher, were utilized to design molecular beacon probes with a high signal/noise ratio. The PH/PN pair was also capable of forming a stable, stacked dimer structure and induced rapid electron transfer that could serve as a good signal reporter for fluorescent nucleic acid detection.
Enantiospecific Total Syntheses of (+)‐Hapalindole H and (−)‐12‐epi‐Hapalindole U
Authors: Dethe Dattatraya H. , Das Saikat , Kumar Vijay B. , Mir Nisar A.
Published: April 2018

Enantiospecific total syntheses of (+)‐hapalindole H and (−)‐12‐epi‐hapalindole U as well as the formal syntheses of (+)‐hapalindole Q and (+)‐12‐epi‐fischerindole U isothiocyanate have been described. Key steps of our approach feature expedient, highly regio‐ and diastereoselective Lewis acid catalyzed Friedel–Crafts reaction of indole with cyclic allylic alcohols and intramolecular reductive Heck reaction. Efficiency of the synthetic route also relies on an alkynyl aluminate complex driven regioselective nucleophilic epoxide opening from a sterically hindered site.
Diastereoselective Synthesis of Highly Substituted, Amino‐ and Pyrrolidino‐Tetrahydrofurans as Lead‐Like Molecular Scaffolds
Authors: Wales Steven M. , Merisor Elena G. , Adcock Holly V. , Pearce Christopher A. , Strutt Ian R. , Lewis William , Hamza Daniel , Moody Christopher J.
Published: April 2018

A series of highly substituted tetrahydrofurans (THFs), decorated with modifiable 2‐aryl, 3‐carboxy and 4‐amino substituents, has been prepared for biological evaluation within the European Lead Factory. Diastereoselective reductive amination of pre‐functionalised 4‐oxofurans, readily prepared from cinnamate esters via oxa‐Michael/Dieckmann annulation, provided the requisite THF cores on gram scale with three contiguous stereocentres, including full substitution at C‐3. In a second series, a pyrrolidine ring was fused to the same oxofuran scaffold via an intramolecular reductive amination, inverting the configuration at C‐4 relative to the other ring substituents. The resulting compounds, which displayed desirable physical properties as lead‐like scaffolds, were derivatised into a small library of 24 compounds, demonstrating their ability to serve as starting points for drug discovery. Ultimately, this chemistry enabled the preparation of 1948 THF‐containing compounds for inclusion in the Joint European Compound Library.
Saturated Heterocyclic Aminosulfonyl Fluorides: New Scaffolds for Protecting‐Group‐Free Synthesis of Sulfonamides
Authors: Zhersh Sergey A. , Blahun Oleksandr P. , Sadkova Iryna V. , Tolmachev Andrey A. , Moroz Yurii S. , Mykhailiuk Pavel K.
Published: April 2018

Cyclic saturated aminosulfonyl fluorides were synthesized as their HCl salts. The compounds were found to be stable upon storage and could be used for the protecting‐group‐free synthesis of sulfonamides. In the presence of the −SO2F group, the nitrogen atom could be modified by means of acylation, arylation, or reductive amination to give products that have high potential for the synthesis of bioactive compounds.
Deep‐Ultraviolet Nonlinear Optical Crystal Cs2Al2(B3O6)2O: A Benign Member of the Sr2Be2(BO3)2O Family with [Al2(B3O6)2O]2− Double Layers
Authors: Fang Zhi , Jiang Xingxing , Duan Meihong , Hou Zhanyu , Tang Changcheng , Xia Mingjun , Liu Lijuan , Lin Zheshuai , Fan Feidi , Bai Lei , Chen Chuangtian
Published: April 2018

For the explorations of deep ultraviolet (DUV) nonlinear optical (NLO) borates, a type of important optoelectronic material, the (BO3)3− group has been long regarded as the sole microscopic optically‐active unit, and toxic Be‐containing raw materials are frequently‐adopted. Herein, a new DUV NLO crystal, Cs2Al2(B3O6)2O (CABO), was designed and synthesized by simultaneously replacing the (BO3)3− groups and Be2+ cations for (B3O6)3− units and Al3+ cations in Sr2Be2(BO3)2O, which possesses a favorable structure, through a chemical co‐substitution approach. CABO exhibits a considerable DUV NLO capability because of the wide band gap and large birefringence originating from the [Al2(B3O6)2O]2− double layers. Remarkably, CABO melts congruently and does not contain the toxic beryllium, which is favorable for bulk‐size crystal growth and practical applications.
Scale‐Up of Innovative Honeycomb Reactors for Power‐to‐Gas Applications – The Project Store&Go
Authors: Schollenberger Dominik , Bajohr Siegfried , Gruber Manuel , Reimert Rainer , Kolb Thomas
Published: April 2018

The German “Energiewende” is heavily based on electric power and, therefore, requests solutions to serve non‐electric energy uses and to store electric energy in large scale. Synthetic natural gas (SNG) produced with hydrogen from water electrolysis and with CO2 from mainly renewable sources is one approach. For the catalytic SNG production efficient removal and utilization of the reaction heat is the main issue. A metallic honeycomb‐like carrier‐based reactor proved in laboratory scale to match this challenge. This type of reactor shows good heat conductivity and enables optimized operation. In the EU‐funded project Store&Go the honeycomb methanation is scaled up to MW‐scale. For this, heat transfer and kinetic data were determined experimentally and used in CFD calculations for the reactor design. Finally a SNG plant with 1 MW feed‐in will be built and fully integrated operation will be shown.
Chemische Reaktionen in Bubble‐Tea‐Bällchen
Authors: Ducci Matthias , Syskowski Sabrina
Published: April 2018

Zusammenfassung und Ausblick

Es werden verschiedene chemische Reaktionen vorgestellt, die im Innern von Alginatbällchen ablaufen. Hierzu werden einige der Reaktanden in die Alginatbällchen bei deren Herstellung eingeschleust, andere diffundieren nachträglich durch den Calciumalginatmantel, der den Bällchen ihre Stabilität verleiht. Auf diese Weise wird zum Beispiel der Zusammenhang zwischen dem Redoxverhalten einiger Redoxsysteme und dem pH‐Wert in beeindruckender Weise sichtbar gemacht. Darüber hinaus treten faszinierende Fluoreszenz‐ und Chemolumineszenzeffekte auf. Insgesamt zeichnen sich die Experimente durch ihre besondere Ästhetik, der leichten Durchführbarkeit und ihrem ressourcenschonenden und damit nachhaltigen Charakter aus.

Zurzeit entwickeln die Autoren Experimente zu organisch‐chemischen Reaktionen in Alginatbällchen sowie zu chemolumineszierenden Alginatbällchen mit Laborchemikalien.
The Moderating Role of Strategic Integration in Performance Improvement Through Purchasing Social Responsibility in Thailand
Authors: Duangjan Chompunoot , Wang Haijun
Published: April 2018

This research aims to understand the performance of purchasing social responsibility (PSR) through moderating effect of purchasing strategic integration. The results show that PSR directly influences purchasing performance, while the relationship between PSR and purchasing performance is partially mediated by organizational learning. Moreover, strategic integration negatively moderates the relationship between PSR and purchasing performance. This study suggests that the adoption of PSR affects the operations of both buyers and suppliers in a supply chain that further encourage organizational learning and increases purchasing efficiency. The results also show that organizations may realize this effect of PSR practices but may focus on other purchasing practices, which affects purchasing performance. Copyright © 2018 ASAC. Published by John Wiley & Sons, Ltd.
The Role of Firms in Resilient Systems: A Multi‐Level Framework
Authors: McKnight Brent
Published: April 2018

In this paper, we articulate a multi‐level resilience‐based framework explaining how firms facilitate stronger system‐level resilience. The framework stresses the importance of firm interdependence, describing how pooled versus sequential/reciprocal patterns of interdependence influence the resilience antecedents of diversity, slack, and redundancy. We argue that the inter‐firm practices of self‐governance and supply chain collaboration function to maintain resilience antecedents at more moderate and effective levels. This work builds on prior resilience research that has remained focused on either firm or system levels of analysis by stressing the value of firm interdependence as an important contingency for effective system resilience. Copyright © 2018 ASAC. Published by John Wiley & Sons, Ltd.