bluuebunny/crossref_metadata_2025_split huggingface dataset:
High‐Pressure Phase Transformations in TiPO4: A Route to Pentacoordinated Phosphorus
Authors: Bykov Maxim , Bykova Elena , Hanfland Michael , Liermann Hanns‐Peter , Kremer Reinhard K. , Glaum Robert , Dubrovinsky Leonid , van Smaalen Sander 
Published: October 2016

AbstractTitanium(III) phosphate, TiPO4 , is a typical example of an oxyphosphorus compound containing covalent P−O bonds. Single‐crystal X‐ray diffraction studies of TiPO4 reveal complex and unexpected structural and chemical behavior as a function of pressure at room temperature. A series of phase transitions lead to the high‐pressure phase V, which is stable above 46 GPa and features an unusual oxygen coordination of the phosphorus atoms. TiPO4‐V is the first inorganic phosphorus‐containing compound that exhibits fivefold coordination with oxygen. Up to the highest studied pressure of 56 GPa, TiPO4‐V coexists with TiPO4‐IV, which is less dense and might be kinetically stabilized. Above a pressure of about 6 GPa, TiPO4‐II is found to be an incommensurately modulated phase whereas a lock‐in transition at about 7 GPa leads to TiPO4‐III with a fourfold superstructure compared to the structure of TiPO4‐I at ambient conditions. TiPO4‐II and TiPO4‐III are similar to the corresponding low‐temperature incommensurate and commensurate magnetic phases and reflect the strong pressure dependence of the spin‐Peierls interactions.
The potential of nanoparticles in stem cell differentiation and further therapeutic applications
Authors: Dayem Ahmed Abdal , Choi Hye Yeon , Yang Gwang‐Mo , Kim Kyeongseok , Saha Subbroto Kumar , Kim Jin‐Hoi , Cho Ssang‐Goo 
Published: October 2016

AbstractTissue regeneration could offer therapeutic advantages for individuals experiencing organ or tissue damage. Recently, advances in nanotechnology have provided various nanomaterials, with a wide range of applications, for modulating stem cell behavior and for further therapeutic applications in tissue regeneration. Defects in cell proliferation and differentiation, a low mechanical strength of scaffolds, and inefficient production of factors that are essential for stem cell differentiation are the current challenges in tissue regeneration. This review provides a brief explanation about the link between nanotechnology and tissue engineering, highlighting the current literature about the interaction between nanoparticles (NPs) and stem cells, the promotional effect of NPs on stem cell differentiation into various lineages, and their possible therapeutic applications. We also tried to describe the mechanism through which NPs regulate the spatial‐temporal release and kinetics of vital growth and differentiation factors, enhance stem cell differentiation, and improve culture conditions for in vivo tissue regeneration. The field of nanotechnology is promising and provides novel nanomaterials and methods with valuable clinical applications in the regenerative medicine. Understanding the mechanism, as well as the toxic effects of NPs in stem cell biology will undoubtedly provide valuable insight into their clinical application in the regenerative medicine.
Applications of Chiral Thiourea‐Amine/Phosphine Organocatalysts in Catalytic Asymmetric Reactions
Authors: Sun Yao‐Liang , Wei Yin , Shi Min 
Published: October 2016

AbstractSince the first example of using a thiourea‐amine organocatalyst was reported in 2003, research on thiourea‐based amines and phosphines in asymmetric catalysis has shown the excellent performance of chiral thiourea‐amine/phosphine organocatalysts in a variety of highly enantioselective reactions. In this Minireview, the iconic catalysts and transformations are highlighted and discussed.
Potassium Poly(heptazine imides) from Aminotetrazoles: Shifting Band Gaps of Carbon Nitride‐like Materials for More Efficient Solar Hydrogen and Oxygen Evolution
Authors: Savateev Aleksandr , Pronkin Sergey , Epping Jan Dirk , Willinger Marc Georg , Wolff Christian , Neher Dieter , Antonietti Markus , Dontsova Dariya 
Published: October 2016

AbstractPotassium poly(heptazine imide) (PHI) is a photocatalytically active carbon nitride material that was recently prepared from substituted 1,2,4‐triazoles. Here, we show that the more acidic precursors, such as commercially available 5‐aminotetrazole, upon pyrolysis in LiCl/KCl salt melt yield PHI with the greatly improved structural order and thermodynamic stability. Tetrazole‐derived PHIs feature long‐range crystallinities and unconventionally small layer stacking distances, leading to the altered electronic band structures as shown by Mott–Schottky analyses. Under the optimized synthesis conditions, visible‐light driven hydrogen evolution rates reach twice the rate provided by the previous gold standard, mesoporous graphitic carbon nitride, which has a much higher surface area. More interestingly, the up to 0.7 V higher valence band potential of crystalline PHI compared with ordinary carbon nitrides makes it an efficient water oxidation photocatalyst, which works even in the absence of any metal‐based co‐catalysts under visible light. To our knowledge, this is the first case of metal‐free oxygen liberation from water.
On the Mechanism of Frustrated Lewis Pair Catalysed Hydrogenation of Carbonyl Compounds
Authors: Das Shubhajit , Pati Swapan K. 
Published: October 2016

AbstractWe have explored the reaction mechanism of the metal‐free B(C6F5)3‐catalysed hydrogenation of carbonyl compounds to the corresponding secondary alcohols by density functional theory calculations. Possible reaction routes have been investigated in detail and the results provide solid support for the mechanism proposed on the basis of experimental observations. The critical role of the ethereal solvent, as an active participant in the hydrogenation process, is highlighted with the ether–borane Lewis pair shown to be involved in the heterolytic activation of H2. The feasiblity of an alternative direct hydrogenation route featuring carbonyl–borane‐mediated H2 cleavage has also been examined. We have also investigated the moisture sensitivity of the catalyst and possible decomposition routes. We found that the catalyst shows appreciable water‐tolerance and that even in the presence of moisture the hydrogenation proceeds through the same mechanism as that followed under anhydrous conditions.
Reactivity of [Ge9{Si(SiMe3)3}3]− Towards Transition‐Metal M2+ Cations: Coordination and Redox Chemistry
Authors: Kysliak Oleksandr , Schrenk Claudio , Schnepf Andreas 
Published: October 2016

AbstractRecently the metalloid cluster compound [Ge9Hyp3]− (1; Hyp=Si(SiMe3)3) was oxidatively coupled by an iron(II) salt to give the largest metalloid Group 14 cluster [Ge18Hyp6]. Such redox chemistry is also possible with different transition metal (TM) salts TM2+ (TM=Fe, Co, Ni) to give the TM+ complexes [Fe(dppe)2][Ge9Hyp3] (3; dppe=1,2‐bis(diphenylphosphino)ethane), [Co(dppe)2][Ge9Hyp3] (4), [Ni(dppe)(Ge9Hyp3)] (5) and [Ni(dppe)2(Ge9Hyp3)]+ (6). Such a redox reaction does not proceed for Mn, for which a salt metathesis gives the first open shell [Hyp3Ge9‐M‐Ge9Hyp3] cluster (2; M=Mn). The bonding of the transition metal atom to 1 is also possible for Ni (e.g., compound 6), in which one or even two nickel atoms can bind to 1. In contrast to this in case of the Fe and Co compounds 3 and 4, respectively, the transition‐metal atom is not bound to the Ge9 core of 1. The synthesis and the experimentally determined structures of 2–6 are presented. Additionally the bonding within 2–6 is analyzed and discussed with the aid of EPR measurements and quantum chemical calculations.
Bifunctional RuII‐Complex‐Catalysed Tandem C−C Bond Formation: Efficient and Atom Economical Strategy for the Utilisation of Alcohols as Alkylating Agents
Authors: Roy Bivas Chandra , Chakrabarti Kaushik , Shee Sujan , Paul Subhadeep , Kundu Sabuj 
Published: October 2016

AbstractCatalytic activities of a series of functional bipyridine‐based RuII complexes in β‐alkylation of secondary alcohols using primary alcohols were investigated. Bifunctional RuII complex (3 a) bearing 6,6’‐dihydroxy‐2,2’‐bipyridine (6DHBP) ligand exhibited the highest catalytic activity for this reaction. Using significantly lower catalyst loading (0.1 mol %) dehydrogenative carbon−carbon bond formation between numerous aromatic, aliphatic and heteroatom substituted alcohols were achieved with high selectivity. Notably, for the synthesis of β‐alkylated secondary alcohols this protocol is a rare one‐pot strategy using a metal–ligand cooperative RuII system. Remarkably, complex 3 a demonstrated the highest reactivity compared to all the reported transition metal complexes in this reaction.
Synthesis of Quaternary‐Carbon‐Containing β2,2‐Amino Acids by the RhI‐Catalyzed Enantioselective Arylation of α‐Substituted β‐Nitroacrylates
Authors: Fang Jo‐Hsuan , Jian Jia‐Hong , Chang Hao‐Ching , Kuo Ting‐Shen , Lee Way‐Zen , Wu Ping‐Yu , Wu Hsyueh‐Liang 
Published: October 2016

AbstractAn enantioselective RhI‐catalyzed conjugate addition reaction of α‐substituted β‐nitroacrylates with various arylboronic acids by using chiral RhI diene catalysts is described for the first time. The addition reaction proceeds under mild conditions in a range of common organic solvents and additives, and it affords the corresponding quaternary‐carbon‐containing α,α‐disubstituted β‐nitropropionate products in up to 63 % yield and 99 % ee. Reaction of either (E)‐ or (Z)‐β‐nitroacrylates provided the same enantiomer of the product, and a range of esters and aryl groups were tolerated. To demonstrate the utility of the method, ethyl (R)‐1,1‐methyl‐1‐phenyl‐3‐nitropropionate, prepared herein, was converted to the non‐proteinogenic β2,2‐amino acid, (R)‐2‐(aminomethyl)‐2‐phenylpropanoic acid, and to the β2,2‐lactam, (R)‐3‐methyl‐3‐phenylazetidin‐2‐one. In addition, a tripeptide, which comprised l‐phenylalanine, l‐alanine, and β2,2‐amino acid 7, was also synthesized.
Glycerol Dehydration to Acrolein Catalyzed by ZSM‐5 Zeolite in Supercritical Carbon Dioxide Medium
Authors: Zou Bin , Ren Shoujie , Ye X. Philip 
Published: October 2016

AbstractSupercritical carbon dioxide (SC‐CO2) has been used for the first time as a reaction medium for the dehydration of glycerol to acrolein catalyzed by a solid acid. Unprecedented catalyst stability over 528 hours of time‐on‐stream was achieved and the rate of coke deposition on the zeolite catalyst was the lowest among extensive previous studies, showing potential for industrial application. Coking pathways in SC‐CO2 were also elucidated for future development. The results have potential implications for other dehydration reactions catalyzed by solid acids.
Agroecosystem research with big data and a modified scientific method using machine learning concepts
Authors: Moran M. Susan , Heilman Philip , Peters Debra P. C. , Holifield Collins Chandra 
Published: October 2016

AbstractLong‐term studies of agroecosystems distributed across the North American continent are providing an extraordinary understanding of regional environmental dynamics. The new Long‐Term Agro‐ecosystem Research (LTAR) network (organized in 2012) has designed an explicit cross‐site research program with multiple U.S. Department of Agriculture (USDA) experimental watersheds, ranges, and forests. Here, we report results from studies using a modified scientific method that includes learning through time that was implemented over the past five years with long‐term data from USDA experimental sites in coordination with other networks. The results offer a compelling argument for the LTAR concept of combining site‐based expertise with network‐wide coordination and collaboration to arrive at more accurate scientific conclusions than possible from individual researchers working alone. Simply put, without site‐based expertise and cross‐site communication working in parallel to provide input, feedback, and refinement to each subsequent step, similar to the way machine learning works, the interpretations and conclusions of these studies would have been incomplete, if not incorrect. Further, the up‐front time commitment to data processing and analytics above the time dedicated to place‐based studies increased the productivity of the team and the impact of the research, unlike the common perception that cross‐site research is often less efficient. In turn, this approach supported a non‐traditional system of credit for co‐authors based on citation impact of the journal selected as the publication outlet with less regard for author order. The LTAR network has embraced this modified scientific method in its shared research strategy and common experiment to address the problematic issues of mixed data quality across studies and sites, co‐author credit, research efficiency, and scientific impact on data‐intensive research. This approach can be combined with other types of collaborative and social media approaches, such as crowdsourcing, to take advantage of the wide range of expertise in the agroecological community as well as other disciplines to move science forward in the time of big data.
Economic Analysis and Potential Feed‐in Tariff of Grid‐Connected PV Systems in Nigeria
Authors: Adaramola Muyiwa S. , Paul Samuel S. 
Published: October 2016

This study presents a feasibility study of grid‐tied PV system in selected locations across the country with focus on cost of energy produced and incentives such as feed‐in tariff and investment support. Based on the study locations and assumptions used in this study, it was estimated that the annual energy generated by the PV system varies between 2885 kWh in Port‐Harcourt in southern region and 4391 kWh in Isa in northern region. The optimal simulation results reveal that the levelized cost of energy varies from one location to another: highest in very low‐energy site (Port‐Harcourt) and lowest in the very high‐energy (Isa). In addition, it is estimated that the feed‐in tariff varies between N76.54/kWh (or US$0.4556/kWh) in Port‐Harcourt and N50.25/kWh (or US$0.2991/kWh) in Isa. It was further observed that the ratio of levelized cost of energy to current electricity tariff is least at Bauchi with a value of 1.22 and highest in Ikeja with a value of 2.95. Consequently, it would easier to sell solar PV idea to individual in Bauchi than those in Ikeja to invest in solar PV. Some of the benefits and potential challenges of implementing feed‐in tariff in Nigeria were also presented. © 2016 American Institute of Chemical Engineers Environ Prog, 36: 305–314, 2017
MR‐guided percutaneous sclerotherapy of low‐flow vascular malformations: Clinical experience using a 1.5 tesla MR system
Authors: O'Mara Daniel M. , DiCamillo Paul A. , Gilson Wesley D. , Herzka Daniel A. , Wacker Frank K. , Lewin Jonathan S. , Weiss Clifford R. 
Published: October 2016

PurposeTo demonstrate the feasibility, safety, and effectiveness of image‐guided sclerotherapy of low‐flow vascular malformations using a 1.5 Tesla (T) MR scanner with real‐time imaging capability and in‐suite fluoroscopy.Materials and MethodsThirty‐three procedures were performed with real‐time 1.5T MR‐guidance on 22 patients with a vascular malformation in the neck (n = 2), chest (n = 6), abdomen and pelvis (n = 15), and extremities (n = 11). Quantitative analysis was performed for changes in (a) planning time, (b) targeting time (interval between needle skin puncture and lesion access), (c) intervention time (interval between needle skin puncture and needle removal), and (d) total procedure time. Qualitative analysis was performed for (a) success of therapy and (b) occurrence of complications.ResultsTechnical success was achieved in 29 of 33 procedures. The average planning time did not significantly change between the first seven procedures and the last seven procedures (P = 0.447). The average targeting time decreased by 0:24:45 (hours:minutes:seconds) (P = 0.043), the average intervention time decreased by 0:26:58 (P = 0.022), and the average procedure time decreased by 0:28:41 (P = 0.046) when comparing the first seven procedures and the last seven procedures. Overall, there was an improvement in the patients' predominant symptoms following 82% of procedures, including a significant decrease in average pain following therapy (P < 0.001). There was a minor complication rate of 3% with no major complications.ConclusionMR‐guided percutaneous sclerotherapy seems to be a safe, effective, and versatile technique for treating low‐flow vascular malformations.Level of Evidence: 3J. Magn. Reson. Imaging 2017;45:1154–1162
Can routine office‐based audiometry predict cochlear implant evaluation results?
Authors: Gubbels Samuel P. , Gartrell Brian C. , Ploch Jennifer L. , Hanson Kevin D. 
Published: October 2016

Objectives/HypothesisDetermining cochlear implant candidacy requires a specific sentence‐level testing paradigm in best‐aided conditions. Our objective was to determine if findings on routine audiometry could predict the results of a formal cochlear implant candidacy evaluation. We hypothesize that findings on routine audiometry will accurately predict cochlear implant evaluation results in the majority of candidates.Study DesignRetrospective, observational, diagnostic study.MethodsThe charts of all adult patients who were evaluated for implant candidacy at a tertiary care center from June 2008 through June 2013 were included. Routine, unaided audiologic measures (pure‐tone hearing thresholds and recorded monosyllabic word recognition testing) were then correlated with best‐aided sentence‐level discrimination testing (using either the Hearing in Noise Test or AzBio sentences test).ResultsThe degree of hearing loss at 250 to 4,000 Hz and monosyllabic word recognition scores significantly correlated with sentence‐level word discrimination test results. Extrapolating from this association, we found that 86% of patients with monosyllabic word recognition scores at or below 32% (or 44% for patients with private insurance) would meet candidacy requirements for cochlear implantation.ConclusionsRoutine audiometric findings can be used to identify patients who are likely to meet cochlear implant candidacy upon formal testing. For example, patients with pure‐tone thresholds (250, 500, 1,000 Hz) of ≥75 dB and/or a monosyllabic word recognition test score of ≤40% have a high likelihood of meeting candidacy criteria. Utilization of these predictive patterns during routine audiometric evaluation may assist hearing health professionals in deciding when to refer patients for a formal cochlear implant evaluation.Level of Evidence4 Laryngoscope, 127:216–222, 2017
Rapid maxillary expansion for pediatric obstructive sleep apnea: A systematic review and meta‐analysis
Authors: Camacho Macario , Chang Edward T. , Song Sungjin A. , Abdullatif Jose , Zaghi Soroush , Pirelli Paola , Certal Victor , Guilleminault Christian 
Published: October 2016

Objectives/HypothesisTo perform a systematic review with meta‐analysis for sleep study outcomes in children who have undergone rapid maxillary expansion (RME) as treatment for obstructive sleep apnea (OSA).Data SourcesPubMed/MEDLINE and eight additional databases.Review MethodsThree authors independently and systematically reviewed the international literature through February 21, 2016.ResultsSeventeen studies reported outcomes for 314 children (7.6 ± 2.0 years old) with high‐arched and/or narrow hard palates (transverse maxillary deficiency) and OSA. Data were analyzed based on follow‐up duration: ≤3 years (314 patients) and >3 years (52 patients). For ≤3‐year follow‐up, the pre‐ and post‐RME apnea–hypopnea index (AHI) decreased from a mean ± standard deviation (M ± SD) of 8.9 ± 7.0/hr to 2.7 ± 3.3/hr (70% reduction). The cure rate (AHI <1/hr) for 90 patients for whom it could be calculated was 25.6%. Random effects modeling for AHI standardized mean difference (SMD) is −1.54 (large effect). Lowest oxygen saturation (LSAT) improved from 87.0 ± 9.1% to 96.0 ± 2.7%. Random effects modeling for LSAT SMD is 1.74 (large effect). AHI improved more in children with previous adenotonsillectomy or small tonsils (73–95% reduction) than in children with large tonsils (61% reduction). For >3‐year follow‐up (range = 6.5–12 years), the AHI was reduced from an M ± SD of 7.1 ± 5.7/hr to 1.5 ± 1.8/hr (79% reduction).ConclusionsImprovement in AHI and lowest oxygen saturation has consistently been seen in children undergoing RME, especially in the short term (<3‐year follow‐up). Randomized trials and more studies reporting long‐term data (≥3‐year follow‐up) would help determine the effect of growth and spontaneous resolution of OSA. Laryngoscope, 2016 Laryngoscope, 127:1712–1719, 2017
Management of acute complicated mastoiditis at an urban, tertiary care pediatric hospital
Authors: Ghadersohi Saied , Young Nancy M. , Smith‐Bronstein Virginia , Hoff Stephen , Billings Kathleen R. 
Published: October 2016

Objectives/HypothesisTo describe the presentation and management of acute complicated mastoiditis in children.Study DesignRetrospective case series.MethodsAn analysis of pediatric patients with acute complicated mastoiditis treated at an urban, tertiary care children's hospital from 2007 to 2014 was performed.ResultsForty‐eight patients presented with a total of 67 complications of acute mastoiditis. Mean age at presentation was 4.8 years (range = 0.1–15.3 years). The most common complications were subperiosteal abscess (n = 22, 45.8%), epidural abscess (n = 16, 33.3%), and sigmoid sinus thrombosis (n = 14, 29.2%). The most common pathogens isolated included Streptococcus pneumoniae (n = 14, 29.2%) and group A streptococcus (n = 10, 20.8%). Multidrug resistance was not associated with complication type. Surgical management included myringotomy ± tympanostomy tube placement in 46 (95.8%) patients (the only surgery in 10), drainage of subperiosteal abscess without mastoidectomy in 18 (37.5%) patients, and mastoidectomy in 21 (43.8%) total patients. Patients presenting with intracranial complications were the most likely to undergo a mastoidectomy. Anticoagulation was used in the management of nine of 14 (64.3%) patients presenting with sigmoid sinus thrombosis. Neurosurgical interventions (n = 7, 14.6% patients) were primarily performed to manage increased intracranial pressure.ConclusionsSubperiosteal abscess was the most common complication of acute mastoiditis, and when occurring as the sole complication was successfully managed with antibiotics and surgical intervention that did not include mastoidectomy. Epidural abscess and sigmoid sinus thrombosis were more prevalent than reported in prior series and were managed more aggressively. These patients were more likely to need neurosurgical interventions.Level of Evidence4. Laryngoscope, 127:2321–2327, 2017
Innovative Technologies in Nanomedicines: From Passive Targeting to Active Targeting/From Controlled Pharmacokinetics to Controlled Intracellular Pharmacokinetics
Authors: Sato Yusuke , Sakurai Yu , Kajimoto Kazuaki , Nakamura Takashi , Yamada Yuma , Akita Hidetaka , Harashima Hideyoshi 
Published: October 2016

Nanomedicines promise to extend drug therapy from small molecular compounds to proteins/nucleic acids/genes. Multifunctional envelope‐type nanodevices (MENDs) have been developed for delivering such molecules to the site of action. The YSK‐MEND contains new types of pH‐responsive cationic lipids to efficiently deliver siRNA to hepatocytes via receptor‐mediated endocytosis and use in treating hepatitis C and B in model mice. The RGD ligand is introduced to target tumor endothelial cells (TEC) and RGD‐MEND is able to send siRNA to TEC to regulate the function of tumor microenvironments. The MITO‐Porter is also developed to target mitochondria via membrane fusion. Antisense oligo RNA in the MITO‐Porter permits the knock down of mitochondrial function. Finally, the ssPalms is designed based on a new concept of pH‐dependent protonation in endosomes and cleavage of SS bonds in the reducing conditions in cytosol. These new technologies promise to stimulate the use of Nanomedicines in the future.
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