bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Unusual Dehydratase Acting on Glycerate and a Ketoreducatse Stereoselectively Reducing α‐Ketone in Polyketide Starter Unit Biosynthesis
Authors: He Hai‐Yan , Yuan Hua , Tang Man‐Cheng , Tang Gong‐Li 
Published: August 2014

AbstractPolyketide synthases (PKSs) usually employ a ketoreductase (KR) to catalyze the reduction of a β‐keto group, followed by a dehydratase (DH) that drives the dehydration to form a double bond between the α‐ and β‐carbon atoms. Herein, a DH*‐KR* involved in FR901464 biosynthesis was characterized: DH* acts on glyceryl‐S‐acyl carrier protein (ACP) to yield ACP‐linked pyruvate; subsequently KR* reduces α‐ketone that yields L‐lactyl‐S‐ACP as starter unit for polyketide biosynthesis. Genetic and biochemical evidence was found to support a similar pathway that is involved in the biosynthesis of lankacidins. These results not only identified new PKS domains acting on different substrates, but also provided additional options for engineering the PKS starter pathway or biocatalysis.
Trans‐Selective Radical Silylzincation of Ynamides
Authors: Romain Elise , Fopp Carolin , Chemla Fabrice , Ferreira Franck , Jackowski Olivier , Oestreich Martin , Perez‐Luna Alejandro 
Published: August 2014

AbstractThe silylzincation of terminal ynamides is achieved through a radical‐chain process involving (Me3Si)3SiH and R2Zn. A potentially competing polar mechanism is excluded on the basis of diagnostic control experiments. The unique feature of this addition across the CC bond is its trans selectivity. One‐pot electrophilic substitution of the CZn bond by CuI‐mediated CC bond formation and subsequent manipulation of the CSi bond provides a modular access to Z‐α,β‐disubstituted enamides.
An Unusual Ring‐Contraction/Rearrangement Sequence for Making Functionalized Di‐ and Triquinanes
Authors: Nagaraju Chinta , Prasad Kavirayani R. 
Published: August 2014

AbstractA novel ring contraction/rearrangement sequence leading to functionalized 2,8‐oxymethano‐bridged di‐ and triquinane compounds is observed in the reaction of various substituted 1‐methyl‐4‐isopropenyl‐6‐oxabicylo[3.2.1]octan‐8‐ones with Lewis acids. The reaction is novel and is unprecedented for the synthesis of di‐ and triquinane frameworks.
Combining Rhodium and Photoredox Catalysis for CH Functionalizations of Arenes: Oxidative Heck Reactions with Visible Light
Authors: Fabry David C. , Zoller Jochen , Raja Sadiya , Rueping Magnus 
Published: August 2014

AbstractDirect, oxidative metal‐catalyzed CH functionalizations of arenes are important in synthetic organic chemistry. Often, (over‐)stoichoimetric amounts of organic or inorganic oxidants have to be used in these reactions. The combination of rhodium and photoredox catalysis with visible light allows the direct CH olefination of arenes. Small amounts (1 mol %) of a photoredox catalyst resulted in the efficient CH functionalization of a broad range of substrates under mild conditions.
A “Schizophotonic” All‐In‐One Nanoparticle Coating for Multiplexed SE(R)RS Biomedical Imaging
Authors: Iacono Pasquale , Karabeber Hazem , Kircher Moritz F. 
Published: August 2014

AbstractSERS nanoprobes for in vivo biomedical applications require high quantum yield, long circulation times, and maximum colloidal stability. Traditional synthetic routes require high metal–dye affinities and are challenged by unfavorable electrostatic interactions and limited scalability. We report the synthesis of a new near‐IR active poly(N‐(2‐hydroxypropyl) methacrylamide) (pHPMA). The integration of various SERS reporters into a biocompatible polymeric surface coating allows for controlled dye incorporation, high colloidal stability, and optimized in vivo circulation times. This technique allows the synthesis of very small (<20 nm) SERS probes, which is crucial for the design of excretable and thus highly translatable imaging agents. Depending on their size, the “schizophotonic” nanoparticles can emit both SERS and fluorescence. We demonstrate the capability of this all‐in‐one gold surface coating and SERS reporter for multiplexed lymph‐node imaging.
Switchable Charge‐Transfer in the Photoelectrochemical Energy‐Conversion Process of Ferroelectric BiFeO3 Photoelectrodes
Authors: Cao Dawei , Wang Zhijie , Nasori  , Wen Liaoyong , Mi Yan , Lei Yong 
Published: August 2014

AbstractInstead of conventional semiconductor photoelectrodes, herein, we focus on BiFeO3 ferroelectric photoelectrodes to break the limits imposed by common semiconductors. As a result of their prominent ferroelectric properties, the photoelectrodes are able to tune the transfer of photo‐excited charges generated either in BiFeO3 or the surface modifiers by manipulating the poling conditions of the ferroelectric domains. At 0 V vs Ag/AgCl, the photocurrent could be switched from 0 μA cm−2 to 10 μA cm−2 and the open‐circuit potential changes from 33 mV to 440 mV, when the poling bias of pretreatment is manipulated from −8 V to +8 V. Additionally, the pronounced photocurrent from charge injection of the excited surface modifiers could be quenched by switching the poling bias from +8 V to −8 V.
Super‐Resolution Imaging of Plasma Membrane Glycans
Authors: Letschert Sebastian , Göhler Antonia , Franke Christian , Bertleff‐Zieschang Nadja , Memmel Elisabeth , Doose Sören , Seibel Jürgen , Sauer Markus 
Published: August 2014

AbstractMuch of the physiology of cells is controlled by the spatial organization of the plasma membrane and the glycosylation patterns of its components, however, studying the distribution, size, and composition of these components remains challenging. A bioorthogonal chemical reporter strategy was used for the efficient and specific labeling of membrane‐associated glycoconjugates with modified monosaccharide precursors and organic fluorophores. Super‐resolution fluorescence imaging was used to visualize plasma membrane glycans with single‐molecule sensitivity. Our results demonstrate a homogeneous distribution of N‐acetylmannosamine (ManNAc)‐, N‐acetylgalactosamine (GalNAc)‐, and O‐linked N‐acetylglucosamine (O‐GlcNAc)‐modified plasma membrane proteins in different cell lines with densities of several million glycans on each cell surface.
Dialdehydes Lead to Exceptionally Fast Bioconjugations at Neutral pH by Virtue of a Cyclic Intermediate
Authors: Schmidt Pascal , Zhou Linna , Tishinov Kiril , Zimmermann Kaspar , Gillingham Dennis 
Published: August 2014

AbstractOne of the open challenges in chemical biology is to identify reactions that proceed with large rate constants at neutral pH values. As shown here, dialdehydes react with O‐alkylhydroxylamines at rates of 500 M−1 s−1 at neutral pH values in the absence of catalysts. The key to these conjugations is an unusually stable cyclic intermediate, which ultimately undergoes dehydration to yield an oxime. The scope and limitations of the method are outlined, as well as its application in bioconjugation and a mechanistic interpretation that will facilitate further developments of reactions with alkylhydroxylamines at low substrate concentrations.
Wood‐derived phenol novolaks and their wood/epoxy biocomposites
Authors: Enjoji Motohiro , Yamamoto Asami , Shibata Mitsuhiro 
Published: August 2014

ABSTRACTGuaiacol novolak (GCN) and wood‐tar creosote novolak (WCN) were synthesized by the reactions of wood‐derived guaiacol and creosote with formalin, respectively, and used as hardeners of sorbitol polyglycidyl ether (SPE). Thermal and mechanical properties of the cured resins (SPE‐GCN and SPE‐WCN) and their biocomposites with wood flour (WF) were compared with those of the materials prepared by using a petroleum‐based phenol novolak (PN). Although tan δ peak temperatures of SPE‐GCN and SPE‐WCN were lower than that of SPE‐PN, that (58.5–70.8°C) of SPE‐GCN/WF(40–50 wt %) was higher than that (56.6–57.0°C) of SPE‐PN/WF(40–50 wt %). Tensile moduli of all the biocomposites increased by the addition of WF, while tensile strengths were rather reduced. When the biocomposites with the same WF content were compared, tensile modulus of SPE‐GCN/WF was higher than that of SPE‐PN/WF. The 5% weight loss temperatures (346–291°C) of SPE‐GCN and SPE‐GCN/WF were comparable to those (338–284°C) of SPE‐PN and SPE‐PN/WF. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41347.
Effects of melt structure on crystallization behavior of isotactic polypropylene nucleated with α/β compounded nucleating agents
Authors: Zhang Qiyan , Chen Zhengfang , Wang Bing , Chen Jinyao , Yang Feng , Kang Jian , Cao Ya , Xiang Ming , Li Huilin 
Published: August 2014

ABSTRACTIn this study, the melt structure of isotactic polypropylene (iPP) nucleated with α/β compounded nucleating agents (α/β‐CNA, composed of the α‐NA of 0.15 wt % Millad 3988 and the β‐NA of 0.05 wt % WBG‐II) was tuned by changing the fusion temperature Tf. In this way, the role of melt structure on the crystallization behavior and polymorphic composition of iPP were investigated by differential scanning calorimetry (DSC), wide‐angle X‐ray scattering (WAXD) and scanning electron microscopy (SEM). The results showed that when Tf = 200°C (iPP was fully molten), the α/β‐CNA cannot encourage β‐phase crystallization since the nucleation efficiency (NE) of the α‐NA 3988 was obviously higher than that of the β‐NA WBG‐II. Surprisingly, when Tf was in 179–167°C, an amount of ordered structures survived in the melt, resulting in significant increase of the proportion of β‐phase (achieving 74.9% at maximum), indicating that the ordered structures of iPP played determining role in β‐phase crystallization of iPP nucleated with the α/β‐CNA. Further investigation on iPP respectively nucleated with individual 3988 and WBG‐II showed that as Tf decreased from 200°C to 167°C, the crystallization peak temperature Tc of iPP/3988 stayed almost constant, while Tc of iPP/WBG‐II increased gradually when Tf < 189°C and became higher than that of iPP/3988 when Tf decreased to 179°C and lower, which can be used to explain the influence of ordered structure and α/β‐CNA on iPP crystallization. Using this method, the selection of α‐NA for α/β‐CNA can be greatly expanded even if the inherent NE of β‐NA is lower than that of the α‐NA. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41355.
The role of the interphase on the shear induced failure of multiwall carbon nanotubes reinforced epoxy nanocomposites
Authors: Chiacchiarelli Leonel Matías , Escobar Mariano Martín , Kenny José María , Torre Luigi , Vazquez Analía 
Published: August 2014

ABSTRACTMultiwall Carbon Nanotubes (MWCNT) with an elevated aspect ratio were chemically functionalized with amines and two types of epoxide groups. Thermogravimetric analysis and Fourier Transform‐Infrared Spectroscopy (FTIR) analysis corroborated that the functionalization degree was substantial (up to 30 wt %) and the presence of a covalent bond with the MWCNT. The functionalized MWCNT (f‐CNT) were incorporated into an epoxy matrix after its dispersion in the diglycidyl ether of bisphenol A (DGEBA) precursor. To induce a shear failure mode, a short‐beam (SB) experimental setup was implemented. The SB shear strength (SBSS) proved that the functionalization had a strong influence on its value. For the case of pristine CNT, a neutral effect was obtained. A strong detrimental effect (−17.2% ± 9.5) was measured for the amine type f‐CNT and a positive effect (up to 10.9% ± 8.9) was measured of the epoxide type f‐CNT. Fractographic analysis of each formulation was correlated with SBSS performance, proving that the surface texture of the fractured samples was strongly correlated to its value. Furthermore, dynamic mechanical analysis proved that the damping factor and the crosslink molecular weight were correlated with the SBSS performance. A lower full width at half maximum of the damping factor was associated to an improvement of SBSS. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41364.
Random and aligned PLLA : PRGF electrospun scaffolds for regenerative medicine
Authors: Díaz‐Gómez Luis , Ballarin Florencia Montini , Abraham Gustavo A. , Concheiro Angel , Alvarez‐Lorenzo Carmen 
Published: August 2014

ABSTRACTRandom and aligned electrospun scaffolds were prepared combining poly(l‐lactic acid) (PLLA) and activated platelet‐rich plasma (PRGF) at various proportions, with the aim of elucidating the role of nanofibers orientation and growth factors on cell attachment and proliferation. PRGF is released from scaffolds in a sustained way for at least 3 weeks, without an initial burst effect. Mesenchymal stem cells (MSCs) seeded on the random scaffolds present a polygonal and random orientation in any direction of the scaffold. On the other hand, aligned scaffolds are able to promote cell attachment and proliferation in the direction of the nanofibers. The incorporation of PRGF in the scaffolds enhances cell proliferation for at least 2 weeks. Overall, aligned electrospun PLLA : PRGF scaffolds can encapsulate growth factors at relatively large proportions and sustain their release to enhance cell attachment and proliferation as well as eliciting cell alignment. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2015,132, 41372.
The use of gait parameters to evaluate pedestrian behavior at scramble phase signalized intersections
Authors: Hediyeh Houman , Sayed Tarek , Zaki Mohamed H. 
Published: August 2014

SummaryPedestrian scramble phasing is usually implemented to reduce pedestrian‐vehicle conflicts and therefore increase the safety of the intersection. However, to adequately determine the benefits of scramble phasing, it is necessary to understand how pedestrians react to such an unconventional design. This study investigates changes in pedestrian crossing behavior following the implementation of a scramble phase by examining the spatiotemporal gait parameters (step length and step frequency). This detailed microscopic‐level analysis provides insight into changes in pedestrian walking mechanisms as well as the effect of various pedestrian and intersection characteristics. The study uses video data collected at a scramble phase signalized intersection in Oakland, California. Gait parameters were found to be influenced by pedestrian gender, age, group size, crosswalk length, and pedestrian signal indications. Both average step length and walking speed were significantly higher for diagonally crossing pedestrians compared with pedestrians crossing on the conventional crosswalks. Pedestrians were found to have the tendency to increase their step length more than their step frequency to increase walking speed. It was also found that, compared with men, women generally increase their walking speed by increasing their step frequency more than step length. However, when in non‐compliance with signal indications, women increase their walking speed by increasing their step length more than step frequency. It was also found that older pedestrians do not significantly change their walking behavior when in non‐compliance with signal indications. Copyright © 2014 John Wiley & Sons, Ltd.
Formation of fluorescent carbon nanodots from kitchen wastes and their application for detection of Fe3+
Authors: Xu Jinjin , Lai Tiantian , Feng Zhiling , Weng Xuexiang , Huang Chaobiao 
Published: August 2014

AbstractThis work reports a scalable synthesis of water‐dispersible fluorescent carbon nanodots based on the simple hydrothermal method (180 °C for 6 h) of kitchen wastes (grape peel for example). We discuss the feasibility of synthesis from kitchen wastes both experimentally and theoretically, and the as‐prepared nanodots have high selectivity for Fe3+ ions based on fluorescence quenching which is due to the complexes between nanodots and metal ions. Copyright © 2014 John Wiley & Sons, Ltd.
The Role of Neglect in Child Fatality and Serious Injury
Authors: Brandon Marian , Bailey Sue , Belderson Pippa , Larsson Birgit 
Published: August 2014

Although there is improved recognition of the pernicious long‐term harm that stems from living with neglect during childhood, neglect is rarely associated with child fatality. This article offers a re‐analysis of neglect in serious case reviews (cases of child death or serious injury related to maltreatment) in England (2003–11) from four consecutive government‐commissioned national two‐yearly studies. It draws on anonymised research information from 46 cases out of a total of over 800 cases. Each case was examined in depth using an ecological transactional approach, grounded in the child's experience, which promotes a dynamic understanding and assessment of the interactions between children and their families and the helping practitioners. The qualitative findings reported explore how circumstances came together when neglect had a catastrophic impact on the child and family presenting in six different ways (deprivational neglect, medical neglect, accidents with elements of forewarning, sudden unexpected deaths in infancy, physical abuse combined with neglect and young suicide). Each of the six categories raised particular issues over and above a common core of concerns around the relationship between the child and his or her parent or carer, and between parents/carers and professionals. © 2014 The Authors. Child Abuse Review published by John Wiley & Sons Ltd.‘neglect is rarely associated with child fatality’‘Each of the six categories raised particular issues’Key Practitioner Messages:

There are no easy answers to curbing potentially fatal neglect – practitioners should be supported to make careful well‐reasoned judgements.
That neglect is not only harmful but can also be fatal should be part of any practitioner's mindset, as with other maltreatment.
To guard against catastrophic neglect, children need to be physically and emotionally healthy and have a safe, healthy living environment.
Practitioners need to be compassionate and sensitively attuned to the relationship between parents and children.‘practitioners need to be compassionate and sensitively attuned to the relationship between parents and children.’
Working Effectively with Neglected Children and Their Families – What Needs To Change?
Authors: Farmer Elaine , Lutman Eleanor 
Published: August 2014

Since practitioners have little research to inform them about how to keep neglected children safe and improve their outcomes, we conducted a study about how risks are managed over time. The research in seven local authorities involved 138 neglected children who were returned from care to their parents and followed up for another five years through reviews of case files and interviews with social workers.‘We conducted a study about how risks are managed over time’Work with neglected children and their families was dogged by ‘inescapable errors’, which we argue will always occur in work over time and need to be deliberately interrupted. Parents were difficult to engage, and over time abuse and neglect were often minimised so that referrals about harm to children did not lead to sufficient protective action. Parents were given too many chances to change, and files lacked information on the development of children on which decisions about intervention could be based. Using written contracts with parents would assist practitioners to assess parental capacity to make the changes required. A new approach to working with neglected children is required which will allow patterns of children's developmental and other progress to be recognised over time, rooted in collecting evidence which could be used in care proceedings if required. Copyright © 2014 John Wiley & Sons, Ltd.‘A new approach is required which will allow patterns of children's developmental and other progress to be recognised over time’Key Practitioner Messages

A new approach to working with neglected children is required which will chart patterns of children's developmental and other progress so that they can be recognised over time – rooted in collecting evidence which could be used in care proceedings if required.
Using written contracts with parents would assist practitioners to assess parental capacity to make the changes required to keep children safe and allow them to develop normally.‘Using written contracts with parents would assist practitioners to assess parental capacity to make the changes required’
Transforming a Wild World: Helping Children and Families to Address Neglect in the Province of Quebec, Canada
Authors: Lacharité Carl 
Published: August 2014

Neglect is a complex social problem with serious consequences for the fulfilment of the needs of a child by adults in the child's immediate family and social network – not only parents, but other adults who come into contact with the child (including professionals). However, child protection systems have difficulty taking into account the social nature and the relational complexity of this issue. In fact, they have, consequently, a tendency to concentrate on the parents' deficiencies with regard to their responsibility to their children. This article describes the theoretical foundation of an ecosystemic and developmental model that forms the basis for the development of integrated child neglect services in Quebec, Canada. It also describes the components and activities that aim to operationalise this ecosystemic and developmental model of child neglect. Copyright © 2014 John Wiley & Sons, Ltd.‘This article describes the theoretical foundation of an ecosystemic and developmental model’Key Practitioner Messages:

Child neglect is characterised by the collapse of the social organisation surrounding children and their parents.
Social action targeting neglect must be based on:

an ecosystemic and developmental understanding of the child's needs and the parents' responsibilities;
a participatory approach involving parents and children;
allowance for the parents' experience of their role in the development of their children;
the creation of normative developmental experiences for the children.‘Child negelct is characterised by the collapse of the social organisation surrounding children and their parents’
Organotin–Oxido Cluster‐Based Multiferrocenyl Complexes Obtained by Hydrolysis of Ferrocenyl‐Functionalized Organotin Chlorides
Authors: You Zhiliang , Möckel Robert , Bergunde Jakob , Dehnen Stefanie 
Published: August 2014

AbstractThree organotin–oxido clusters were formed by hydrolysis of ferrocenyl‐functionalized organotin chloride precursors in the presence of NaEPh (E=S, Se). [RFcSnCl3⋅HCl] (C; RFc = CMe2CH2C(Me)NNC(Me)Fc) and [SnCl6]2− formed {(RFcSnCl2)3[Sn(OH)6]}[SnCl3] (3 a) and {(RFcSnCl2)3[Sn(OH)6]}[PhSeO3] (3 b), bearing an unprecedented [Sn4O6] unit, in a one‐pot synthesis or stepwise through [(RFcSnCl2)2Se] (1) plus [(RFcSnCl2)SePh] (2). A one‐pot reaction starting out from FcSnCl3 gave [(FcSn)9(OH)6O8Cl5] (4), which represents the largest Fc‐decorated Sn/O cluster reported to date.
The Importance of Hydration Thermodynamics in Fragment‐to‐Lead Optimization
Authors: Ichihara Osamu , Shimada Yuzo , Yoshidome Daisuke 
Published: August 2014

AbstractUsing a computational approach to assess changes in solvation thermodynamics upon ligand binding, we investigated the effects of water molecules on the binding energetics of over 20 fragment hits and their corresponding optimized lead compounds. Binding activity and X‐ray crystallographic data of published fragment‐to‐lead optimization studies from various therapeutically relevant targets were studied. The analysis reveals a distinct difference between the thermodynamic profile of water molecules displaced by fragment hits and those displaced by the corresponding optimized lead compounds. Specifically, fragment hits tend to displace water molecules with notably unfavorable excess entropies—configurationally constrained water molecules—relative to those displaced by the newly added moieties of the lead compound during the course of fragment‐to‐lead optimization. Herein we describe the details of this analysis with the goal of providing practical guidelines for exploiting thermodynamic signatures of binding site water molecules in the context of fragment‐to‐lead optimization.