bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ecological and cultural shifts of hunter‐gatherers of the Jomon period paralleled with environmental changes
Authors: Kusaka Soichiro , Yamada Yasuhiro , Yoneda Minoru 
Published: August 2018

AbstractObjectivesHolocene hunter‐gatherers adapted to climatic and environmental changes over time. Carbon and nitrogen stable isotope analysis of human skeletal remains from the Inariyama shell mound of the Final Jomon period have revealed large dietary variations in the population. This study analyzed radiocarbon dates of these individuals to test temporal changes in diet and its relationship with tooth ablation.Materials and MethodsTwenty‐nine human skeletal remains from Inariyama were included in this study. Extracted bone collagen samples were purified to graphite. Then, radiocarbon dating of these samples was performed using the accelerator mass spectrometer.ResultsThe radiocarbon ages of Inariyama ranged about, 3,230–2,140 cal BP and showed three peaks of occupation. In the early and late phases, terrestrial resource consumption and incisor extraction were observed, while marine resource consumption and canine extraction were observed in the middle phase.DiscussionThese temporal changes of diet and tooth ablation types occurred in parallel with climatic cooling and environmental change and help reveal how Holocene hunter‐gatherers adapted to the changing environments.
Female status, food security, and stature sexual dimorphism: Testing mate choice as a mechanism in human self‐domestication
Authors: Gleeson Ben Thomas , Kushnick Geoff 
Published: August 2018

AbstractObjectivesHumans exhibit multiple anatomical and behavioral signatures of domestication syndrome, leading evolutionary‐minded scholars to suggest Homo sapiens is a “self‐domesticated” species. We examined one of three mechanisms proposed to explain human self‐domestication—that is, intersexual selection against reactive aggression. We hypothesized that this process has been, at least in part, caused by context‐dependent female preferences for less‐aggressive males. We predicted that societies where women have higher social status will show relatively elevated signs of self‐domestication—as indicated by lower stature sexual dimorphism (SSD)—and that this relationship should be mediated by food security.Materials and methodsTo test our prediction, we used male and female stature data for 28 societies from the Standard Cross‐Cultural Sample. We applied multivariate regression to examine our hypothesis while controlling for theoretically important confounders.ResultsWe found convincing support for the prediction that the relationship between SSD and female status is mediated by food security. As predicted, higher female status was associated with less sexual dimorphism and the effect is stronger when food resources are secure.DiscussionContext‐dependent female mate choices significantly contribute to lower SSD, suggesting female mate choice is likely to have played an influential role in human self‐domestication. Future research on this theme will benefit by including more of the expected symptoms of human self‐domestication and examining other potential drivers of this process.
Variation in obstetric dimensions of the human bony pelvis in relation to age‐at‐death and latitude
Authors: Auerbach Benjamin M. , King Kathyrn A. , Campbell Ryan M. , Campbell Meadow L. , Sylvester Adam D. 
Published: August 2018

AbstractObjectivesPrevious studies associate females who died in young adulthood with narrower obstetric pelvic dimensions, presumably in association with obstetric insufficiency (though this causal relationship is unresolved). In this study, we examine whether females within groups living at higher latitudes present this pattern, as high‐latitude groups have larger pelvic dimensions than groups previously examined. These patterns are compared with males. We assess whether there is evidence for younger ages‐at‐death in females to have been in response to natural selection against narrower true pelvis dimensions.MethodsWe measured 14 pelvic dimensions in 327 adults (188 females, 139 males), representing archaeological sites from mid‐latitude and high‐latitude North America. Individuals were placed into a “young” or “not young” age‐at‐death category. Latitude, sex, and age‐at‐death groups were compared using ANOVAs and scaled variance, and evidence for selection was examined with F‐tests.ResultsPelvic dimensions were larger in high‐latitude females and males. Females but not males who died at younger ages had smaller pelvic canals than older individuals, especially in the mediolateral inlet and anteroposterior outlet dimensions. Variance in all pelvic dimensions is equal between the two female age‐at‐death groups.ConclusionsWe found narrower obstetrical dimensions in the female pelvis among individuals who died at younger ages. However, statistically equivalent variances in the two female age‐at‐death groups does not support natural selection on pelvic dimensions as leading to younger ages at death. We instead argue that this difference is result of continued growth due to remodeling in the pelvis occurring in females, but not males, after early adulthood.
Event‐related deep brain stimulation of the subthalamic nucleus affects conflict processing
Authors: Ghahremani Ayda , Aron Adam R. , Udupa Kaviraja , Saha Utpal , Reddy Duemani , Hutchison William D. , Kalia Suneil K. , Hodaie Mojgan , Lozano Andres M. , Chen Robert 
Published: August 2018

ObjectiveMany lines of evidence suggest that response conflict recruits brain regions in the cortical–basal ganglia system. Within the basal ganglia, deep brain recordings from the subthalamic nucleus (STN) have shown that conflict triggers a transient increase in low‐frequency oscillations (LFOs; 2–8Hz). Here, we deployed a new method of delivering short trains of event‐related deep brain stimulation (DBS) to the STN to test the causal role of the STN and its associated circuits in conflict‐related processing.MethodsIn a double‐blind design, we stimulated the STN in patients with Parkinson disease by locking brief trains of DBS to specific periods of the trial within a Stroop task.ResultsStimulation had a specific effect on conflict compared to nonconflict trials by relatively speeding responses on conflict trials (ie, reducing the Stroop effect, defined as the difference in reaction time between conflict and nonconflict trials) when it was delivered in the preresponse period in the preparation phase. Stimulation also increased errors when it was delivered early in the response window. This latter result corresponded to the timing of the conflict‐induced increase in LFOs observed in the absence of stimulation but was not directly related to the reduction in the Stroop effect.InterpretationThese results support the theory that the time of LFO increase recorded from the STN corresponds to a conflict‐processing function. They also provide one of the first demonstrations of event‐related DBS of the STN in humans during a cognitive control paradigm. Ann Neurol 2018;84:515–526
Synthese und Charakterisierung von Cs4Ga6Q11 (Q=S, Se) – Chalkogenogallate mit außergewöhnlichen polymeren Anionen
Authors: Friedrich Daniel , Greim Dominik , Schlosser Marc , Siegel Renée , Senker Jürgen , Pfitzner Arno 
Published: August 2018

AbstractDurch kontrollierte thermische Zersetzung von CsN3 in Gegenwart stöchiometrischer Mengen binärer Galliumchalkogenide und der elementaren Chalkogene wurden zwei neue ternäre Chalkogenogallate Cs4Ga6Q11 (Q=S, Se) gewonnen. Beide Verbindungen kristallisieren isotyp in der Raumgruppe P
(Nr. 2). Das auffälligste Strukturmerkmal dieser Chalkogenogallate sind die ungewöhnlichen strangförmigen anionischen Dreier‐Doppelketten
[Ga6Q11]4− aus sechs ecken‐ und kantenverknüpften GaQ4‐Tetraedern in der kleinsten Translationseinheit. 133Cs‐NMR‐spektroskopische Messungen und Rechnungen auf DFT‐Niveau zeigen einen ionischen Bindungscharakter der Caesiumteilstruktur. Die halbleitenden Verbindungen Cs4Ga6S11 (Eg=3.14 eV) und Cs4Ga6Se11 (Eg=2.41 eV) wurden weiterhin mittels UV/Vis‐Spektroskopie und ergänzenden DFT‐Rechnungen studiert. Die 133Cs‐MAS‐NMR‐Spektren sind charakteristisch für kationisches Caesium, und Schwingungsspektren zeigen zwei deutlich getrennte Bereiche, die jeweils den Ga‐Q‐Valenz‐ und Ga‐Q‐Deformationsschwingungen zugeordnet werden können.
Backbone‐Enabled Directional Peptide Macrocyclization through Late‐Stage Palladium‐Catalyzed δ‐C(sp2)−H Olefination
Authors: Bai Zengbing , Cai Chuangxu , Yu Zonglun , Wang Huan 
Published: August 2018

AbstractC−H activation methods for peptide macrocyclization have the potential to provide peptidomimetics and cyclic peptides with expanded structural diversity. Now, a highly versatile peptide macrocyclization strategy via late‐stage palladium‐catalyzed δ‐C(sp2)−H olefination of phenylalanine residues has been developed. This method utilizes peptide backbone amides as internal directing groups and allows facile macrocyclization of peptides in the N‐to‐C direction. Combined with the previously developed β‐C(sp3)−H arylation method for peptide macrocyclization in the C‐to‐N direction, a pair of palladium‐catalyzed reactions were obtained that are directionally orthogonal, and the first example of one‐pot synthesis of bicyclic peptides via Pd‐catalyzed β‐C(sp3)−H and δ‐C(sp2)−H activation is demonstrated.
Barcoding mit Nukleinsäuren: Anwendung der DNA‐Sequenzierung als molekulares Zählwerk
Authors: Liszczak Glen , Muir Tom W. 
Published: August 2018

AbstractTechniken der Hochdurchsatz‐DNA‐Sequenzierung haben eine Revolution in der Genomik ausgelöst, die in viele Bereiche der Lebens‐ und Naturwissenschaften eingedrungen ist. Die bemerkenswerten Eigenschaften der parallelen DNA‐Sequenzierung, wie hohe Sensitivität und Spezifität, hoher Durchsatz und Multiplexkapazität, führten zu Anwendungen als “molekulare Zählwerke” (molecular counter) für die Entdeckung niedermolekularer und peptidbasierter Inhibitoren, für die Hochdurchsatzbiochemie, die Protein‐ und Zelldetektion, die Diagnostik und sogar die Materialienwissenschaften. Ein wichtiger Aspekt bei der Extrapolation der DNA‐Sequenzierung auf “nichtklassische” Anwendungen besteht in der Anforderung, Nukleinsäure‐Barcodes an die interessierenden Entitäten anzuhängen. In diesem Aufsatz werden die chemischen und biochemischen Ansätze beschrieben, die ein einfaches Nukleinsäure‐Barcoding von proteinhaltigen und nichtproteinhaltigen Materialien ermöglicht haben. Wir zeigen Beispiele für die Verwendung von nachgelagerten Technologien, die durch DNA‐codierte Moleküle ermöglicht wurden. In Anbetracht der Tatsache, dass kommerziell erhältliche Hochdurchsatzsequenzer vor weniger als 15 Jahren eingeführt wurden, glauben wir, dass sich diesbezügliche Anwendungen auch in den kommenden Jahren zur Marktreife entwickeln werden.
Ultrafast Dynamics of a “Super” Photobase
Authors: Sheng Wei , Nairat Muath , Pawlaczyk Patrick D. , Mroczka Elizabeth , Farris Benjamin , Pines Ehud , Geiger James H. , Borhan Babak , Dantus Marcos 
Published: August 2018

AbstractMolecular reactivity can change dramatically with the absorption of a photon due to the difference of the electronic configurations between the excited and ground states. Here we report on the discovery of a modular system (Schiff base formed from an aldehyde and an amine) that upon photoexcitation yields a more basic imine capable of intermolecular proton transfer from protic solvents. Ultrafast dynamics of the excited state conjugated Schiff base reveals the pathway for proton transfer, culminating in a 14‐unit increase in pKa to give the excited state pKa*>20 in ethanol.
Enhancing Selectivity and Kinetics in Oxidative Photocyclization by Supramolecular Control
Authors: Haldar Ritesh , Diring Stéphane , Samanta Pralok K. , Muth Marius , Clancy William , Mazel Antoine , Schlabach Sabine , Kirschhöfer Frank , Brenner‐Weiß Gerald , Pati Swapan K. , Odobel Fabrice , Wöll Christof 
Published: August 2018

AbstractPhotochemical reactions typically proceed via multiple reaction pathways, yielding a variety of isomers and products. Enhancing the selectivity is challenging. Now, the potential of supramolecular control for oxidative photocyclization of a tetraarylethylene, containing a stereogenic −C=C− bond, is demonstrated. In solution, this photochemical reaction produces three constitutional isomers (substituted phenanthrenes), with slow kinetics. When the reactant is assembled into a crystalline framework, only one product forms with accelerated kinetics. Key to this selectivity enhancement is the integration into a surface grown metal–organic framework (SURMOF); the dramatic gain in selectivity is ascribed to the hindrance of the rotational freedom of the −C=C− double bond. The structure of the MOF is key; the corresponding reaction in the solid does not result in such a high increase in selectivity. A striking change of luminescence properties after photocyclization is observed.
Enzymatic Cascade Reactions in Biosynthesis
Authors: Walsh Christopher T. , Moore Bradley S. 
Published: August 2018

AbstractEnzyme‐mediated cascade reactions are widespread in biosynthesis. To facilitate comparison with the mechanistic categorizations of cascade reactions by synthetic chemists and delineate the common underlying chemistry, we discuss four types of enzymatic cascade reactions: those involving nucleophilic, electrophilic, pericyclic, and radical reactions. Two subtypes of enzymes that generate radical cascades exist at opposite ends of the oxygen abundance spectrum. Iron‐based enzymes use O2 to generate high valent iron‐oxo species to homolyze unactivated C−H bonds in substrates to initiate skeletal rearrangements. At anaerobic end, enzymes reversibly cleave S‐adenosylmethionine (SAM) to generate the 5′‐deoxyadenosyl radical as a powerful oxidant to initiate C−H bond homolysis in bound substrates. The latter enzymes are termed radical SAM enzymes. We categorize the former as “thwarted oxygenases”.
Effects of addition mode on Zn–Co double metal cyanide catalyst for synthesis of oligo(propylene‐carbonate) diols
Authors: An Na , Li Qifeng , Yin Ning , Kang Maoqing , Wang Junwei 
Published: August 2018

Zn–Co double metal cyanide (DMC) complexes are promising catalytic systems for copolymerization of epoxide and CO2. In the work reported, Zn–Co DMC catalysts were prepared by parallel‐flow dropping, forward dropping and reverse dropping methods, aiming to provide an insight into the effect of addition mode on catalyst structure and catalytic performance. Catalytic properties were evaluated using the copolymerization reaction of propylene oxide (PO) and CO2 in the presence of chain transfer agent. The results indicated that the factors that affect crystalline state are different for different modes. And excess zinc chloride is the prerequisite for organic ligands to be retained in the catalyst and affect the structure. In addition, a catalyst with flower‐like morphology was obtained with the parallel‐flow dropping method which provided larger surface area. An appropriate O/Zn value ensured abundant active PO which would suppress the backbiting process by forming consecutive PO units adjacent to CO2 units. Oligo(propylene‐carbonate) diols with average molecular weight of 1020 g mol−1, CO2 incorporation of 24.92% and WPC of 5.14 wt% were obtained at 80 °C and 2 MPa.
Effect of hydrophilic additive and PVC polymerization degree on morphology and electrochemical properties of PVC‐based heterogeneous cation‐exchange membrane
Authors: Khoiruddin Khoiruddin , Ariono Danu , Subagjo Subagjo , Wenten I Gede 
Published: August 2018

ABSTRACTMembrane solution composition is one of the important factors that determine properties of ion‐exchange membranes. In this study, PVC‐based heterogeneous cation‐exchange membranes were prepared by the solution casting method. Effects of a hydrophilic additive [poly(ethylene glycol), PEG400] and degree of polymerization of poly(vinyl chloride) (PVC) on the morphology and electrochemical properties of the cation‐exchange membranes were investigated. The results revealed that the hydrophilic additive can improve membrane properties, including water uptake (Wu), ion‐exchange capacity (IEC), conductivity, and permselectivity. The improvements might be associated with an increase in accessibility of functional sites in the membrane matrix due to a higher hydrophilicity, indicated by a reduction of water contact angle and the greater void fraction shown by scanning electron microscopy. However, the permselectivity slightly decreased when the additive concentration was increased further. Meanwhile, increasing the degree of polymerization and PVC concentration resulted in higher permselectivity and lower conductivity, which might be due to a better resin distribution and a lower void fraction. Overall, the prepared membranes had relatively good conductivities (up to ∼2.5 mS/cm) and permselectivities (up to ∼0.92). In general the conductivity increased with increasing Wu and IEC, while the permselectivity showed the opposite trends. This could be associated with the efficacy of Donnan exclusion indicated by the IEC/Wu ratio and the Donnan equilibrium constant of the cation (K+). © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46690.
A phase separation method toward PPTA–polypropylene nanocomposite separator for safe lithium ion batteries
Authors: He Lianyuan , Qiu Teng , Xie Chunjie , Tuo Xinlin 
Published: August 2018

ABSTRACTThe building of separators with high thermal stability and security is important for lithium ion batteries. A novel, simple and successive process, which aims at coating poly‐p‐phenylene terephthamide (PPTA) onto commercial polypropylene (PP) separators, has been demonstrated. Without any additional binder, the PPTA nanofiber coating layer sticks to the porous PP separators by physical anchoring, endowing the composite separators with modified wettability toward electrolytes and heat resistance. Meanwhile, migration routes for lithium ions are guaranteed by the porous structure controlled by the self‐assembly of the fibrillar units during the nonsolvent induced phase separation. The cells equipped with the composite separators show better cycling performances. Moreover, the system based on the composite separators shows a sharp drop in ion conductivity after heat treatment at 200 °C for a certain period, indicating the shutdown effect of the composite separators, which can contribute to additional safety of lithium ion batteries. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 134, 46697
Temperature, pH, and reduction triple‐stimuli‐responsive inner‐layer crosslinked micelles as nanocarriers for controlled release
Authors: Zhang Kehu , Liu Jiangtao , Ma Xiao , Lei Lei , Li Yan , Yang Hong , Lei Zhongli 
Published: August 2018

ABSTRACTTemperature, pH, and reduction triple‐stimuli‐responsive inner‐layer crosslinked micelles as nanocarriers for drug delivery and release are designed. The well‐defined tetrablock copolymer poly(polyethylene glycol methacrylate)–poly[2‐(dimethylamino) ethyl methacrylate]–poly(N‐isopropylacrylamide)–poly(methylacrylic acid) (PPEGMA‐PDMAEMA‐PNIPAM‐PMAA) is synthesized via atom transfer radical polymerization, click chemistry, and esterolysis reaction. The tetrablock copolymer self‐assembles into noncrosslinked micelles in acidic aqueous solution. The core‐crosslinked micelles, shell‐crosslinked micelles, and shell–core dilayer‐crosslinked micelles are prepared via quaternization reaction or carbodiimide chemistry reaction. The crosslinked micelles are used as drug carriers to load doxorubicin (DOX), and the drug encapsulation efficiency with 20% feed ratio reached 59.2%, 73.1%, and 86.1%, respectively. The cumulative release rate of DOX is accelerated by single or combined stimulations. The MTT (3‐(4,5‐Dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) assay verifies that the inner‐layer crosslinked micelles show excellent cytocompatibility, and DOX‐loaded micelles exhibit significantly higher inhibition for HepG2 cell proliferation. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46714.
Hybrid organosiloxane material/metal oxide composite as efficient anticorrosive coatings for mild steel in a saline medium
Authors: Suleiman Rami K. , Kumar A. Madhan , Sorour Ahmad A. , Al‐Badour Fadi A. , El Ali Bassam 
Published: August 2018

ABSTRACTHybrid sol–gel materials have been found very promising anticorrosive coatings for metal substrates. In this article, the synthesis of novel hybrid organic‐inorganic sol–gel polymer; starting from tetraethyl orthosilicate, (3‐aminopropyl) trimethoxysilane, dimethoxy‐methyl‐octadecylsilane and polydimethylsiloxane, silanol terminated precursors, is reported. The hybrid polymer has been further loaded individually as well with five different metal oxides, then deposited on mild steel panels. All cured coating formulations have been characterized using thermogravimetric analysis, contact angle measurements, electrochemical impedance spectroscopy, vicker‐microhardness, surface roughness, and critical load analyses. Results have revealed that the parent coating exhibits excellent thermal stability and hydrophobic nature with minor observed changes on the two properties for the metal oxide‐loaded coatings. Electrochemical impedance and visual inspection results indicated excellent corrosion protection performance for all metal oxide composite coatings (except magnesium oxide) on steel when immersed in 3.5% NaCl solution for a prolonged time. Furthermore, the coating containing molybdenum oxide exhibited a maximum hardness, homogeneity, and adherence to the steel surface. The developed coating formulations in this study can be considered as a promising alternative to the currently‐used toxic chromate and phosphate coatings. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 134, 46718
Electrospun‐electrosprayed hydroxyapatite nanostructured composites for bone tissue regeneration
Authors: Gandhimathi Chinnasamy , Venugopal Jayarama Reddy , Ramakrishna Seeram , Srinivasan Dinesh Kumar 
Published: August 2018

ABSTRACTElectrospinning and electrospraying process provides a versatile approach for the fabrication of biocomposite nanofibrous scaffolds (NFS) with structural, mechanical, and biological properties is to mimick the native extracellular matrix. The present study was aimed to fabricate NFS of poly(l‐lactic acid)‐co‐poly(3‐caprolactone) (PLACL), silk fibroin (SF) and hydroxyapatite (HA) by blending (b) and spraying (s) methods. The biocomposite NFS were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy, water contact angle, tensile strength, fourier transform infrared spectroscopy (FTIR) analysis. The fabricated biocomposite NFS showed pore size around 1.5–7.8 μm and porosity of 68–93% with fiber diameter ranging from 213 ± 78 to 340 ± 52 nm. Furthermore, the mesenchymal stem cells (MSCs) were cultured on the biocomposite NFS and the cell interaction, proliferation, mineralization, and osteocalcin expression were analyzed by FESEM, MTS assay, alizarin Red S staining, and immunofluorescence analysis, respectively. The presence of bioactive SF/HA molecules supported biological functions namely cell attachment, proliferation, and differentiation of MSCs into osteoblasts. The observed results suggested that the biocomposite PLACL/SF/HA(s) NFS stimulated osteogenic differentiation of MSCs as evident from alkaline phosphatase activity, mineralization, and expression of osteocalcin for bone tissue engineering. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46756.