bluuebunny/crossref_metadata_2025 huggingface dataset:
Les figures des plantes et animaux d'usage en medecine, a rare work published by F. A. P. de Garsault in 1764
Authors: WELTER-SCHULTES F. W. , KLUG R. , LUTZE A.
Published: July 2008

Between 1764 and 1767 the artist and naturalist F. A. P. de Garsault published several editions of the five-volume work Les figures des plantes et animaux d'usage en medecine, in which hundreds of plants (four volumes) and animals (one volume) were figured and presented with French and Latin names. A strict absence of polynominal Latin names in the animal volume is a surprising contrast to the botanical volumes where many polynominal names were used. Although several Latin zoological names entered taxonomy in the years after 1764, some of which are still in current usage, the rare work has remained almost unknown to zoologists. Zoologists presumably have not found the work any more in libraries since long before 1900, because in zoological publications work and taxa have erroneously been attributed to the physician and zoologist E. L. Geoffroy, while in botanical bibliographies Garsault's true authorship was maintained.
Aristotle's observations of the foraging interactions of the red mullet (Mullidae: Mullus spp) and sea bream (Sparidae: Diplodus spp)
Authors: TIPTON JASON A.
Published: July 2008

A brief but detailed observation which Aristotle made regarding the foraging behavior of the red mullet (Mullus surmuletus) is examined closely in order to better understand the substance of the discussion. Aristotle's description of the heterospecific red mullet/sea bream foraging behavior is evaluated in light of contemporary observations and life history characteristics. Possible methods, including underwater observations with the use of diving equipment and observations in fish ponds, employed by Aristotle in making these observations are discussed. I also speculate on the ways in which the red mullet/sea bream interaction might be thought of as gregarious behavior according to Aristotle.
Hybrid CdSe Nanoparticle–Carbazole Dendron Boxes: Electropolymerization and Energy‐Transfer Mechanism Shift
Authors: Park Yushin , Taranekar Prasad , Park Jin Young , Baba Akira , Fulghum Timothy , Ponnapati Ramakrishna , Advincula Rigoberto C.
Published: July 2008

Carbazole containing ligand dendrons are designed based on second generation polybenzyl ether dendrons (2GPO). This is subsequently used for directly synthesizing and capping CdSe nanoparticles in contrast to ligand exchange for introducing functionality. The stable hybrid CdSe‐2GPO quantum dot nanoparticles have characteristic energy‐transfer properties from the donor carbazole peripheral groups to the acceptor CdSe nanoparticles, i.e., overlap of the fluorescence of the carbazole with the absorbance of the CdSe nanoparticle resulting in an enhanced fluorescence with concentration through Förster resonance energy transfer (FRET). However, electropolymerization of the peripheral electroactive carbazole units result in a red‐shift in absorbance and quenching in fluorescence. This is attributed to a reversed molecular orbital energy order with respect to the electropolymerized carbazole dendron and CdSe nanoparticle. The hole‐transfer results in fluoresence quenching and charge transfer between the CdSe nanoparticles and the polycarbazole peripheral units. The photoelectric alteration may yet provide for an interesting electro‐optical or sensing device application based on electrochemical properties of the hybrid material.
Microwave Arcing Induced Formation and Growth Mechanisms of Core/Shell Metal/Carbon Nanoparticles in Organic Solutions
Authors: Hsin Yu‐Lin , Lin Chia‐Fen , Liang Yu‐Chia , Hwang Kuo Chu , Horng Jia‐Cherng , Ho Ja‐an Annie , Lin Chun‐Cheng , Hwu Jih Ru
Published: July 2008

Well‐graphitized core/shell iron/carbon nanoparticles (Fe@CNPs) were formed in toluene solutions containing Fe(CO)5‐C60/70 via an novel microwave arcing process. High temperature γ‐Fe phase was found to be stable at room temperature when encapsulated inside graphene shells. In the absence of C60/70, the structures of graphene shells are poor. Pre‐synthesized Co nanoparticles were used as templates for the growth of graphene shells in toluene‐C60/70 solutions. Via acid etching and removal of the central core Co nanoparticles, hollow carbon nanoparticles could be obtained. Further thermal annealing by focused microwave irradiation leads to merging of small core/shell metal/carbon nanoparticles into large ones, as well as conversion of body centered cubic (bcc) α‐Fe to face centered cubic (fcc) γ‐Fe. The possible growth mechanisms of core/shell metal/carbon nanoparticles were discussed.
Imaging Surface Immobilization Chemistry: Correlation with Cell Patterning on Non‐Adhesive Hydrogel Thin Films
Authors: Takahashi Hironobu , Emoto Kazunori , Dubey Manish , Castner David G. , Grainger David W.
Published: July 2008

High‐fidelity surface functional group (e.g., N‐hydroxysuccinimide (NHS) reactive ester) patterning is readily and reliably achieved on commercial poly(ethylene glycol) (PEG)‐based polymer films already known to exhibit high performance non‐fouling properties in full serum and in cell culture conditions. NHS coupling chemistry co‐patterned with methoxy‐capped PEG using photolithographic methods is directly spatially imaged using imaging time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) and principal components statistical analysis. Patterned NHS surface reactive zones are clearly resolved at high sensitivity despite the complexity of the polymer matrix chemistry. ToF‐SIMS imaging also reveals the presence of photo‐resist residue remaining from typical photolithography processing methods. High cross‐correlation between various ion‐derived ToF‐SIMS images is observed, providing sensitive chemical corroboration of pattern chemistry and biological reactivity in complex milieu. Surface‐specific protein coupling is observed first by site‐selective reaction of streptavidin with NHS patterns, followed by identical patterns of biotinylated Alexa‐labeled albumin coupling. This suggests that streptavidin immobilized on the patterns remains bioactive. Fluorescently labeled full serum is shown to react selectively with NHS‐reactive regions, with minimal signal from methoxy‐capped regions. Insufficient serum is adsorbed under any conditions to these surfaces to support cell attachment in serum‐containing media. This reflects the high intrinsic non‐adsorptive nature of this chemistry. Fibroblasts attach and proliferate in serum culture only when a cell adhesion peptide (RGD) is first grafted to NHS regions on the PEG‐based surfaces. Longer‐term serum‐based cell culture retains high cell‐pattern fidelity that correlates with chemical imaging of both the NHS and RGD patterns and also lack of cell adhesion to methoxy‐capped regions. Cell staining shows orientation of adherent cells within the narrow patterned areas. Cell patterns are consistently retained beyond 15 days in serum media.
Directed Self‐Assembly of Gradient Concentric Carbon Nanotube Rings
Authors: Hong Suck Won , Jeong Wonje , Ko Hyunhyub , Kessler Michael R. , Tsukruk Vladimir V. , Lin Zhiqun
Published: July 2008

Hundreds of gradient concentric rings of linear conjugated polymer, (poly[2‐methoxy‐5‐(2‐ethylhexyloxy)‐1,4‐ phenylenevinylene], i.e., MEH‐PPV) with remarkable regularity over large areas were produced by controlled “stick‐slip” motions of the contact line in a confined geometry consisting of a sphere on a flat substrate (i.e., sphere‐on‐flat geometry). Subsequently, MEH‐PPV rings were exploited as a template to direct the formation of gradient concentric rings of multiwalled carbon nanotubes (MWNTs) with controlled density. This method is simple, cost effective, and robust, combining two consecutive self‐assembly processes, namely, evaporation‐induced self‐assembly of polymers in a sphere‐on‐flat geometry, followed by subsequent directed self‐assembly of MWNTs on the polymer‐templated surfaces.
Microcapsules Containing a Biomolecular Motor for ATP Biosynthesis
Authors: He Qiang , Duan Li , Qi Wei , Wang Kewei , Cui Yue , Yan Xuehai , Li Junbai
Published: July 2008

Over the past two decades, advances in modern biology and nanotechnology have enabled a rapid development in the design and building of biomimetic functional materials. ATP synthase is one of the most extensively studied molecular machines because it can be used as a rotary motor in the design of novel nanodevices and it can also continuously synthesize ATP in an artificial environment. A lot of research efforts have focused on assembling ATP synthase in biomimetic systems so that a complex cellular process can be constructed in a controllable manner. As we summarize here, layer‐by‐layer assembled microcapsules have proved to be a suitable cellular mimetic structure, which can be applied for engineering active biomimetic systems with a cellular process. An added benefit is that these assembled microcapsules can be used as bioenergy containers and thus ATP supply on demand.

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Nanostructured Materials for Electrochemical Energy Conversion and Storage Devices
Authors: Guo Yu‐Guo , Hu Jin‐Song , Wan Li‐Jun
Published: July 2008

One of the greatest challenges for our society is providing powerful electrochemical energy conversion and storage devices. Rechargeable lithium‐ion batteries and fuel cells are amongst the most promising candidates in terms of energy densities and power densities. Nanostructured materials are currently of interest for such devices because of their high surface area, novel size effects, significantly enhanced kinetics, and so on. This Progress Report describes some recent developments in nanostructured anode and cathode materials for lithium‐ion batteries, addressing the benefits of nanometer‐size effects, the disadvantages of ‘nano’, and strategies to solve these issues such as nano/micro hierarchical structures and surface coatings, as well as developments in the discovery of nanostructured Pt‐based electrocatalysts for direct methanol fuel cells (DMFCs). Approaches to lowering the cost of Pt catalysts include the use of i) novel nanostructures of Pt, ii)new cost‐effective synthesis routes, iii) binary or multiple catalysts, and iv) new catalyst supports.

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Organic Functional Molecules towards Information Processing and High‐Density Information Storage
Authors: Jiang Guiyuan , Song Yanlin , Guo Xuefeng , Zhang Deqing , Zhu Daoben
Published: July 2008

In this Progress Report, we discuss our recent achievements in design and synthesis of new functional molecules towards information processing at the molecular level and high‐density information storage. These include: 1) new molecular switches, logic gates, and combinational logic circuits based on molecules and ensembles with photochromic spiropyran units that undergo reversible structural transformation among multistates, in response to external inputs such as light, protons, and metal ions; 2) high‐density information storage, mainly focusing on nanometer‐scale electrical recording based on the conductance transition of organic molecules, and multimode data storage on multiresponsive molecules. Relevant progress and an outlook in this area are also discussed.

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Supramolecular Chiroptical Switches Based on Achiral Molecules
Authors: Qiu Yunfeng , Chen Penglei , Guo Peizhi , Li Yuangang , Liu Minghua
Published: July 2008

Chirality plays an important role in biological and material sciences. By introducing chiral elements into functional materials, new properties are created and an increase in information density can be achieved. Chiral properties of functional materials do not only rely on molecular structure, but also on supramolecular interaction between the building blocks. In contrast to the generally accepted opinion that chiral systems should include chiral molecules, this Research News introduces the role of achiral molecules in realizing chiral properties in films and gel‐like materials. Even a system that is entirely composed of achiral molecules can exhibit interesting chiroptical properties in supramolecular ultrathin films. This article demonstrates how achiral molecules can be assembled into supramolecular chiral films and organogels. It further shows how the incorporated achiral molecules can be used to switch the chiral properties of these supramolecular films and organogels.
Solid‐Phase Synthesis of [5.5]‐Spiroketals
Authors: Sommer Stefan , Kühn Marc , Waldmann Herbert
Published: July 2008

An efficient and reliable multi‐step synthesis of 251 natural product‐like [5.5]‐spiroketals on solid supports has been developed. As central key step, a double intramolecular hetero‐Michael (DIHMA) reaction to alkynones was applied. The sequence allows for introduction of numerous substituents on the scaffold and for variation of stereochemistry. [5.5]‐Spiroketals bearing an additional ketone were obtained in high overall yields. Further diversification was achieved by reduction of the ketone and reductive amination using polymer‐supported borohydride, Grignard reaction and conversion to oxime derivatives in the solution phase.
Studies toward the Synthesis of (−)‐Zampanolide: Preparation of the Macrocyclic Core
Authors: Troast Dawn M. , Yuan Jiayi , Porco John A.
Published: July 2008

Studies towards the synthesis of the macrocyclic core of (−)‐zampanolide are reported. The synthetic approach features a one‐pot reduction/vinylogous aldol reaction for construction of the C‐15–C‐20 fragment, an intramolecular silyl‐modified Sakurai (ISMS) reaction for construction of the 2,6‐cis‐disubstitutedexo‐methylene pyran subunit, and use of ansp2‐sp3Stille reaction for macrocyclization.
Enzyme‐Catalyzed Synthesis of a Hybrid N‐Linked Oligosaccharide using N‐Acetylglucosaminyltransferase I
Authors: Chen Rui , Pawlicki Mark A. , Hamilton Brian S. , Tolbert Thomas J.
Published: July 2008

The soluble catalytic domain of human N‐acetylglucosaminyltransferase I was purified from Escherichia coli and utilized in the enzyme‐catalyzed conversion of high mannose N‐linked oligosaccharide 1 into the rare hybrid oligosaccharide 2. Analysis of the reaction showed that the conversion of high mannose 1 into hybrid oligosaccharide 2 proceeded to 100% completion as assessed by MALDI‐TOF‐MS. Purification of the large polar oligosaccharide by gel filtration and silica gel chromatography afforded a 42% isolated yield of oligosaccharide 2. This enzyme‐catalyzed reaction can be utilized to produce rare hybrid oligosaccharides for biochemical and structural studies.
Chiral Lithium Salts of Phosphoric Acids as Lewis Acid–Base Conjugate Catalysts for the Enantioselective Cyanosilylation of Ketones
Authors: Hatano Manabu , Ikeno Takumi , Matsumura Tokihiko , Torii Shinobu , Ishihara Kazuaki
Published: July 2008

The catalytic enantioselective cyanosilylation of aromatic ketones was developed by using chiral lithium salts of (R)‐BINOL‐ or (S)‐BINAM‐derived phosphoric acid compounds. In the presence of 10 mol% of chiral conjugate lithium salts, the corresponding tertiary cyanohydrins were obtained in high yields with moderate to high enantioselectivities. This is the first efficient example of asymmetric catalysis using lithium salts of synthetically useful chiral phosphoric acid compounds. A possible catalytic mechanism and transition states are also discussed as a preliminary working hypothesis.
A pK determination method for proteins from titration curves using principle component analysis
Authors: Shim Jaesool , Dutta Prashanta , Ivory Cornelius F.
Published: July 2008

Principal component analysis (PCA) technique is used for the precise determination of pK values from titration curves of amphoteric molecules, such as proteins and amino acids. A regression model is developed based on the effective charge of amphoteric molecules. Partial domain method, a new algorithm, is introduced to minimize or remove errors in extracted pK values from experimental (titration curve) data with hidden errors, such as sampling errors or experimental uncertainties. For the validation of our algorithm, 3 pK values are determined from the titration curves of glutamic acid and lysine. The extracted pKs are in exact agreement with the original pKs if partial domain method is used to obtain pKs from an exact (uncertainty free) titration curve. In addition, the effects of various uncertainty levels (1%, 2% and 3% noise) in the experimental titration curves are tested using both partial and full domain methods. Analytic results show that partial domain method is very effective in reducing the errors in extracted pKs especially at larger value of redundant number. Next, partial domain based PCA method is applied to extract 5 pKs from the experimental titration curve of hen egg‐white lysozyme protein. These pK values are then used to simulate the isoelectric focusing of lysozyme protein in the presence of 25 biprotic ampholytes in a 2‐D (two‐dimensional) straight microchannel. The transient, as well as focused state behaviors of lysozyme protein are compared between original titration curve (20 pKs) and approximated titration curve (5 pKs) cases. Although there are minor differences at the early stages of focusing, the focusing time, position, and shapes of protein and ampholytes are identical at focused state. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Approximations for unsteady‐state diffusion and reaction in porous catalyst and their application to packed‐bed reactor
Authors: Kim Dong Hyun
Published: July 2008

In this study, three approximations for unsteady‐state diffusion, a linear adsorption, and a first‐order reaction in a catalyst particle are presented. The time‐domain approximations are based on a first‐, a second‐, and a third‐order approximation of the Laplace‐domain solution of the exact partial differential equation for the catalyst. All the coefficients in the approximate equations are obtained as explicit functions of the Thiele modulus and easy to evaluate. In reactor modeling with the approximations, it is observed that the ratio of the space time in the reactor and the diffusion time in the catalyst is also an important parameter affecting the accuracy of the resulting model. A longer space time or shorter diffusion time improves the prediction of the approximate reactor model so that even the first‐order approximation is found to be sufficiently accurate when the ratio is over 0.9. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Investigation of solid–gas reaction heat transformer system with the consideration of multistep reactions
Authors: Wang C. , Zhang P. , Wang R. Z.
Published: July 2008

The performance of solid–gas reaction heat transformer system using MnCl2 and CaCl2 was investigated with the consideration of multistep reactions between CaCl2 and NH3. The reactions between CaCl2 and NH3 could be CaCl2·2/4NH3 and CaCl2·4/8NH3. The simulated results were verified by the experimental data. From the analysis results, it was concluded that the two reactions between CaCl2 and NH3 existed simultaneously. The favored conditions for the simultaneous occurrence of multistep reactions were discussed. The main reaction in the system with the initial state of CaCl2·2NH3 and CaCl2·4NH3 were designated as the reaction of CaCl2·2/4NH3 and CaCl2·4/8NH3, respectively. It was concluded that high driving temperature TM, large relative gas volume, and large specific heat transfer area were the favored conditions for the simultaneous occurrence of multistep reactions in the systems both with the initial state of CaCl2·2NH3 and CaCl2·4NH3. High initial charging pressure P0 was favored for the system with the initial state of CaCl2·2NH3, while low P0 was favored for the system with the initial state of CaCl2·4NH3. The impacts of the simultaneous occurrence of multistep reactions on the system performance indicators [temperature lift, specific power, and system coefficient of performance (COP)] were also investigated in this article. It was concluded that the occurrence of the reaction of CaCl2·4/8NH3 for the initial state of CaCl2·2NH3 led to better system performance, i.e., larger temperature lift, larger specific power, and larger system COP. However, the occurrence of the reaction of CaCl2·2/4NH3 for the initial state of CaCl2·4NH3 would lead to lower specific power. The temperature lift and system COP were larger for the initial state of CaCl2·4NH3; while the cycle period was shorter for the initial state of CaCl2·2NH3. © 2008 American Institute of Chemical Engineers AIChE J, 2008
COMT val158met modulates association between brain white matter architecture and IQ
Authors: Li Jun , Yu Chunshui , Li Yonghui , Liu Bing , Liu Yong , Shu Ni , Song Ming , Zhou Yuan , Zhu Wanlin , Li Kuncheng , Jiang Tianzi
Published: July 2008

The intelligence quotient (IQ) is typically associated with the architecture of gray and white matter in specific brain regions, and this association appears to be genetically based. However, specific sources of genetic variation for the association have not been studied extensively. Using diffusion tensor imaging in 15 mental retardation patients and 80 healthy volunteers, we studied the association between white matter architecture and IQ and also investigated the effects of COMT val158met on this association. The results showed that fractional anisotropy (FA) values in the prefrontal lobe and the hippocampus formation were associated with IQ and that val158met may affect this association. Subjects who were val homozygous showed steeper slopes for regression of the FA value on IQ than met carriers. Our findings suggest that COMT val158met may contribute to intelligence by affecting the association between IQ and the white matter architecture in the prefrontal lobe and the hippocampal formation. © 2008 Wiley‐Liss, Inc.
Taste difference thresholds for monosodium glutamate and sodium chloride in pigtail macaques (Macaca nemestrina) and spider monkeys (Ateles geoffroyi)
Authors: Laska Matthias , Persson Suorra Josefin , Bautista Rosa Mariela Rivas , Hernandez Salazar Laura Teresa
Published: July 2008

The purpose of this study was to determine taste difference thresholds for monosodium glutamate (MSG) and sodium chloride (NaCl) in pigtail macaques (Macaca nemestrina) and spider monkeys (Ateles geoffroyi). Using a two‐bottle preference test of brief duration, three animals of each species were presented with four different reference concentrations of 50, 100, 200, and 400 mM of a tastant and tested for their ability to discriminate these from lower concentrations of the same tastant. The just noticeable differences (JNDs), expressed as Weber ratios (ΔI/I), were found to range from 0.1 to 0.5 for MSG and 0.2 to 0.45 for NaCl in the pigtail macaques, with a significant tendency for higher Weber ratios with higher reference concentrations. In the spider monkeys, JNDs ranged from 0.15 to 0.4 for MSG and 0.1 to 0.25 for NaCl, with Weber ratios staying fairly constant across the reference concentrations tested. Thus, the JNDs were found to be generally similar in both species and to be at least as low as those found in humans for MSG and NaCl, as well as those found in spider monkeys for sucrose. The results support the assumption that both pigtail macaques and spider monkeys may use differences in perceived intensity of MSG and NaCl as a criterion for food selection. Am. J. Primatol. 70:839–847, 2008. © 2008 Wiley‐Liss, Inc.
Female social dynamics in a provisioned free‐ranging band of the Sichuan snub‐nosed monkey (Rhinopithecus roxellana) in the Qinling mountains, China
Authors: Zhang Peng , Watanabe Kunio , Li Baoguo
Published: July 2008

Little information is available on the social dynamics of the Sichuan snub‐nosed monkeys (Rhinopithecus roxellana). Here, we provide 5‐year observational data on a provisioned free‐ranging band in the Qinling Mountains, central China, from October 2001 to December 2005. The results of this study suggested that females place a high priority on maintaining long‐term relationships with other female in their one‐male units (OMUs). Females had more social interactions with unit members than with nonunit individuals. They showed relatively high rates of affiliation with their unit females, intermediate levels with the resident males, and low levels with individuals outside the unit. Females had few interactions with other resident males. Social interactions, especially affiliative interactions, were more symmetrical between focal females and their unit females than between focal females and the resident males. Thus female social interactions appeared to resemble those of other female‐bonded primate societies. On the other hand, female transfers occurred sometimes. We recorded 11 cases of female immigration and 5 cases of female disappearance, 1 case of female intraband shift, and 2 cases of “merging of OMUs,” which suggested that unit females might be loose‐knit in this species. We discussed influencing factors on female Sichuan snub‐nosed monkey social dynamics, by comparing them with those of Hamadryas and gelada baboons that also have multilevel societies. Am. J. Primatol. 70:1013–1022, 2008. © 2008 Wiley‐Liss, Inc.
Food transfer in common marmosets: parents change their tolerance depending on the age of offspring
Authors: Saito Atsuko , Izumi Akihiro , Nakamura Katsuki
Published: July 2008

Food transfer is considered to provide infants with additional nutrients during weaning, and in fact, its frequency peaks around this time. However, the mechanisms underlying such food transfer remain unclear. In this study, we investigated whether adult common marmosets (Callithrix jacchus) change their tolerance to offspring begging for food depending on the offspring's age. We used four families consisting of breeding pairs, older offspring (29–49 weeks old), and younger offspring (7–15 weeks old). To directly compare the responses of a parent with its older and younger offspring, we placed one parent and one offspring in a testing space at one time. We presented foods where only the parent could reach them to ensure that the foods were transferred from the parent to offspring. Younger offspring showed more interest in food being held by the parents than older offspring. Parents refused older offspring more frequently than younger offspring and transferred food more often to younger offspring than to older offspring. There was no difference in all behavioral categories between fathers and mothers. These results suggest that both fathers and mothers are more tolerant to weanlings, but their tolerance decreases as offspring mature. Am. J. Primatol. 70:999–1002, 2008. © 2008 Wiley‐Liss, Inc.
Assessing mandibular shape variation within Gigantopithecus using a geometric morphometric approach
Authors: Miller Steven F. , White Jessica L. , Ciochon Russell L.
Published: July 2008

This study provides a survey of mandibular shape in a sample of extant hominoids (Pan, Gorilla, Pongo, and Hylobates), as well as extinct Asian and Eurasian taxa (Ouranopithecus, Sivapithecus, and Gigantopithecus) in order to compare overall shape similarity. Results presented call into question differences in mandible shape recently used to distinguish Gigantopithecus giganteus from Gigantopithecus blacki and to justify resurrecting a different generic designation, “Indopithecus,” for the former. It is concluded that while the two large‐bodied Asian taxa may have been adapted to slightly different dietary niches with different geographic and temporal ranges, the unique mandibular/dental characters that the two taxa share should not be viewed as independent evolutionary developments. Am J Phys Anthropol, 2008. © 2008 Wiley‐Liss, Inc.
What is it going to be? Pattern and potential function of natal coat change in sexually dichromatic redfronted lemurs (Eulemur fulvus rufus)
Authors: Barthold Julia , Fichtel Claudia , Kappeler Peter
Published: July 2008

In some primate species, pelage colorations at birth contrast with adult colorations. The intensity of natal coats and their phylogenetic distribution is highly variable within primates. Natal coat coloration seems to change to adult coloration in most species when infants become independent from their mothers, but an accepted functional explanation for natal coats is not available. Here we describe pelage coloration change in sexually dichromatic redfronted lemurs (Eulemur fulvus rufus) in Kirindy Forest, and propose a new functional hypothesis for this phenomenon. In this species, infants are born with adult male coloration and female infants subsequently undergo a change in coloration. Using digital pictures and behavioral data collected on eight mother‐offspring dyads from birth until the end of the coloration change, we 1) described timing and pattern of pelage developmentin redfronted lemur infants and 2) examined behavioral developmental correlates of the coloration change. The color change took place between 7 and 17 weeks of age and coincided with advanced physical independence; a pattern also found in monochromatic primate species with natal coats. No behavioral differences between male and female infants were found. Hypotheses about the ultimate function of natal coats focusing on enhanced infant care or reduced infanticide risk did not explain the pelage change in redfronted lemurs. The natal pelage pattern in this species may instead serve as sexual mimicry. Accordingly, female infants may mimic males during the most vulnerable developmental phase to avoid sex‐specific aggression by adult females in a species with intense female–female aggression and competition. Am J Phys Anthropol, 2009. © 2008 Wiley‐Liss, Inc.
Craniometric variation of the Ainu: An assessment of differential gene flow from Northeast Asia into Northern Japan, Hokkaido
Authors: Hanihara Tsunehiko , Yoshida Kohzo , Ishida Hajime
Published: July 2008

In and after the latest Neolithic period in Japan (∼B.P. 2,300 years), there were two distinct waves of migration from eastern Asia. One is well known as successive episodes in which indigenous inhabitants of main‐island Japan were intruded on by new arrivals with advanced technology, and of a different genetic stock. Another migration of people and culture, identified as the Okhotsk culture, reached the northeastern part of Hokkaido. As opposed to main‐island Japan, the morphological continuity from the Neolithic to recent inhabitants in Hokkaido (Ainu) is notable, so that the evidence of admixture easily could have escaped notice. In this study, the effects of gene flow from an outside source on the pattern of among‐group variation of Hokkaido Ainu are examined by means of two models. One is the R‐matrix model comparing observed and expected craniometric variation for estimating differential external gene flow into a region. The other is a simple simulation model that estimates admixture in a population with two parental populations. The two approaches give similar results. The results suggest the possibility of admixture between the migrants from Northeast Asia, the Okhotsk culture people, and the indigenous inhabitants in Hokkaido during the 5th to 12th centuries A.D., at least in northeastern Hokkaido. Such gene flow may have a certain degree of effect on the genetic structure of recent Ainu. The findings further suggest morphological heterogeneity in Northeast Asia during the Holocene that has relevance for understanding the morphological heterogeneity seen through time in the New World. Am J Phys Anthropol 2008. © 2008 Wiley‐Liss, Inc.
Brief communication: Skeletal biology past and present: Are we moving in the right direction?
Authors: Hens Samantha M. , Godde Kanya
Published: July 2008

In 1982, Spencer's edited volume A History of American Physical Anthropology: 1930–1980 allowed numerous authors to document the state of our science, including a critical examination of skeletal biology. Some authors argued that the first 50 years of skeletal biology were characterized by the descriptive‐historical approach with little regard for processual problems and that technological and statistical analyses were not rooted in theory. In an effort to determine whether Spencer's landmark volume impacted the field of skeletal biology, a content analysis was carried out for the American Journal of Physical Anthropology from 1980 to 2004. The percentage of skeletal biology articles is similar to that of previous decades. Analytical articles averaged only 32% and are defined by three criteria: statistical analysis, hypothesis testing, and broader explanatory context. However, when these criteria were scored individually, nearly 80% of papers attempted a broader theoretical explanation, 44% tested hypotheses, and 67% used advanced statistics, suggesting that the skeletal biology papers in the journal have an analytical emphasis. Considerable fluctuation exists between subfields; trends toward a more analytical approach are witnessed in the subfields of age/sex/stature/demography, skeletal maturation, anatomy, and nonhuman primate studies, which also increased in frequency, while paleontology and pathology were largely descriptive. Comparisons to the International Journal of Osteoarchaeology indicate that there are statistically significant differences between the two journals in terms of analytical criteria. These data indicate a positive shift in theoretical thinking, i.e., an attempt by most to explain processes rather than present a simple description of events. Am J Phys Anthropol 2008. © 2008 Wiley‐Liss, Inc.
Temporal squama shape in fossil hominins: Relationships to cranial shape and a determination of character polarity
Authors: Terhune Claire E. , Deane Andrew S.
Published: July 2008

In 1943, Weidenreich described the squamosal suture of Homo erectus as long, low, and simian in character and suggested that this morphology was dependent upon the correlation between the size of the calvarium and the face. Many researchers now consider this character to be diagnostic of H. erectus. The relationship between cranial size and shape and temporal squama morphology, however, is unclear, and several authors have called for detailed measurements of squamosal variation to be collected before any conclusions are drawn regarding the nature of the morphology observed in H. erectus. Thirteen fossil and extant taxa were examined to address two questions: 1) Are size and shape of the temporal squama correlated with cranial vault morphology? and 2) Is the H. erectus condition plesiomorphic? To answer these questions, measurements were collected and indices were calculated for squamosal suture height, length, and area in relation to metric variables describing cranial size and shape. A two‐dimensional morphometric study was also completed using High Resolution‐Polynomial Curve Fitting (HR‐PCF) to investigate correlations between curvature of the squamosal suture and curvature of the cranial vault. Results of both analyses indicate that squamosal suture form is related to cranial size and shape. Furthermore, the plesiomorphic condition of the squamosal suture for hominins was identified as high and moderately arched; this condition is retained in H. erectus and is distinct from the great ape condition. It is suggested that this similarity is the result of increased cranial length without a corresponding increase in cranial height. Am J Phys Anthropol, 2008. © 2008 Wiley‐Liss, Inc.
The mineralized osteocyte: A living fossil
Authors: Bell Lynne S. , Kayser Mike , Jones Chris
Published: July 2008

We report here on an enigmatic and biologically mysterious event in which a single cell, the osteocyte, mineralizes in vivo and in this process the cell's organelles, cytoskeleton and membrane, are mineralized in a dying state. That the bony lacuna in which the lone osteocyte resides becomes infilled with mineral in vivo is not a new observation and was noted by early microscopists. This study has applied scanning and transmission electron microscopy to modern, archaeological, and fossil bone to investigate the mineral and organic structure and content of this cell. The results from this study revealed that within this mineral lies a visibly identifiable cell, which has an apoptotic‐like morphology. The mechanisms by which this cell mineralizes are so intimate chemically that remnant cell organelles, membranes, cytoskeleton, and potentially nucleic bodies are morphologically identifiable. We have further identified mineralized osteocytes surviving in archaeological and fossil mammal bone up to 5 million years BP. The significance of our findings demonstrates that a single cell may itself mineralize in vivo via an unknown set of biochemical events. Importantly, the location and survival of extra cellular and cellular proteins, including nuclear and mitochondrial DNA in bone after death, has been an area of some speculation, and this unique fossil cell provides a preservation locus within human and mammalian bone, which might be fruitfully targeted in future biomolecular studies. Am J Phys Anthropol, 2008. © 2008 Wiley‐Liss, Inc.
Brief Communication: Latent toxoplasmosis and salivary testosterone concentration—Important confounding factors in second to fourth digit ratio studies
Authors: Flegr Jaroslav , Lindová Jitka , Pivoñková Věra , Havlíček Jan
Published: July 2008

A sexually dimorphic characteristic, the second to fourth digit ratio (2D:4D ratio), has been shown to reflect the prenatal concentration of sex steroid hormones and to correlate with many personality, physiological, and life history traits. The correlations are usually stronger for the right than the left hand. Most studies have shown that the 2D:4D ratio does not vary with age or postnatal concentration of sex steroid hormones. Recently, a strong association between left hand 2D:4D ratio and infection with a common human parasite Toxoplasma has been reported. We hypothesized that the confounding effect of Toxoplasma infection on left hand 2D:4D ratio could be responsible for the stronger association between different traits and right hand rather than left hand 2D:4D ratio. This confounding effect of toxoplasmosis could also be responsible for the difficulty in finding an association between 2D:4D ratio and age or postnatal steroid hormone concentration. To test this hypothesis, we analyzed the association between sex and age and 2D:4D ratio in a population of 194 female and 106 male students with and without controlling for the confounding variables of Toxoplasma infection and testosterone concentration. Our results showed that the relationship between age and sex and 2D:4D ratio increased sharply when Toxoplasma infection and testosterone concentration were controlled. These results suggest that left hand 2D:4D ratio is more susceptible to postnatal influences and that the confounding factors of Toxoplasma infection, testosterone concentration and possibly also age, should be controlled in future 2D:4D ratio studies. Because of a stronger 2D:4D dimorphism in Toxoplasma‐infected than Toxoplasma‐free subjects, we predict that 2D:4D ratio dimorphism as well as right hand/left hand 2D:4D ratio dimorphism will be higher in countries with a high prevalence of Toxoplasma infection than in those with a low prevalence. Am J Phys Anthropol, 2008. © 2008 Wiley‐Liss, Inc.
Halbleiterdrähte und ‐bänder als flexible Bauelemente für die Hochleistungselektronik
Authors: Baca Alfred J. , Ahn Jong‐Hyun , Sun Yugang , Meitl Matthew A. , Menard Etienne , Kim Hoon‐Sik , Choi Won Mook , Kim Dae‐Hyeong , Huang Young , Rogers John A.
Published: July 2008

In diesem Aufsatz werden die Eigenschaften und die Herstellung anorganischer Halbleitermaterialien behandelt, die als aktive Elemente für Hochleistungstransistoren und Stromkreise in großflächigen, flexiblen und biegestabilen elektronischen Bauteilen eingesetzt werden können. Die Realisierung hoher Leistungsdichten auf Niedertemperaturpolymeren ist eine technische Herausforderung für die Makroelektronik. Die Produktion qualitativ hochwertiger anorganischer Materialien in Form von Drähten, Bändern, Membranen, Schichten und Stäben nach “Bottom‐up”‐ und “Top‐down”‐Verfahren und die Strategien zur Montage dieser Bauteile auf plastischen Substraten werden daher besonders betont. Wichtige Fortschritte auf dem Gebiet dehnbarer und biegsamer anorganischer Halbleitermaterialien und die Grundlagen dieser mechanischen Stabilität sowie dreidimensionale Konstruktionen werden diskutiert. Abschließend werden die Perspektiven dieses vielversprechenden Forschungsfelds beleuchtet.
Die optische Aktivität achiraler Substanzen
Authors: Claborn Kacey , Isborn Christine , Kaminsky Werner , Kahr Bart
Published: July 2008

Ausgerichtete achirale Molekule und Kristalle mit D2d‐Symmetrie oder einer der nichtenantiomorphen Untergruppen S4, C2v oder Cs können beim Durchstrahlen in einer beliebigen Richtung eine Drehung der Schwingungsebene von linear polarisiertem Licht bewirken. Dies ist in der Kristalloptik eine unangefochtene Tatsache, der Unterricht für Studenten der organischen Chemie vermittelt hingegen eine widersprüchliche Ansicht. Der vorliegende Kurzaufsatz verschafft einen Überblick über Messungen und Rechnungen zu den chiroptischen Eigenschaften einiger achiraler Substanzen und Kristalle. Prototypisch für Verbindungen, die nach van't Hoff optisch inaktiv sein sollten, sind Methanderivate mit vier identischen Liganden, die durch Spiegelebenen in Beziehung stehen. Die Untersuchung der optischen Aktivität einfacher achiraler Verbindungen wie H2O und NH3 vermittelt weitreichende chiroptische Gesetzmäßigkeiten, die oft im Zusammenhang mit chiralen Stoffen übersehen werden. Hier wird anhand gruppentheoretischen Überlegungen, des Transformationsverhaltens von Tensoren und intuitiver Skizzen gezeigt, warum einige achirale azentrische Verbindungen optisch aktiv sind, andere hingegen nicht.
The First cis‐Dioxido Uranyl Compound under Scrutiny
Authors: Villiers Claude , Thuéry Pierre , Ephritikhine Michel
Published: July 2008

Die Identität einer cis‐Dioxido‐Uranylverbindung, über die P. B. Duval et al. kürzlich berichtet haben, wird in Frage gestellt. Grund für die Zweifel ist die strukturelle Charakterisierung von drei anderen Verbindungen, die ausgehend von den beschriebenen Reaktionspartnern erhalten wurden.
The Road to Non‐Enzymatic Molecular Networks
Authors: Dadon Zehavit , Wagner Nathaniel , Ashkenasy Gonen
Published: July 2008

This Minireview gives an overview of recent progress in the design and analysis of chemical systems that utilize template‐directed autocatalytic and cross‐catalytic processes as a means of wiring dynamically interacting molecules. Synthetic networks comprising two to nine replicating species are discussed. It is shown that for larger systems, more catalytic pathways must be manipulated to control the entire network topology and specific functionality of the individual species or subnetworks. Cellular biochemistry is an example of a natural functional molecular network; synthetic self‐organized networks can provide additional models of complex systems.
Preparation and pH‐sensitivity of polyacrylonitrile (PAN) based porous hollow gel fibers
Authors: Shen Xinyuan , Ji Yali , Wang Jue
Published: July 2008

Polyacrylonitrile based porous hollow gel fibers were prepared from PAN hollow fibers by oxidation and subsequent alkaline treatment. Fourier‐transform infrared (FTIR), X‐ray diffraction, and scanning electron microscope (SEM) analyses showed that the PAN porous hollow gel fiber was a kind of amphoteric fiber due to the combination of cationic groups of pyridyl and anionic groups of carboxyl; after gelation the hollow channel and finger‐like pores on the fiber walls were conserved. The effects of cyclization reaction degree, alkaline solution concentration, and alkaline treatment time on the mechanical properties or pH‐sensitive behavior of the porous hollow gel fibers were investigated. The elongation/contraction behavior was studied in detail. It was found that the gel fiber exhibited a large swelling in an alkaline solution and contracting in an acid solution; the swelling change in length was above 90%; the responsive time of elongation/contraction was less than 20 s; the maximum contraction force was 20 N/cm2; and pH‐sensitivity was reversible. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Influence of organoclay and preparation technique on the morphology of polyamide6/polystyrene/organoclay nanocomposites
Authors: Yang Jintao , Sun Li , Xiang Saifei , He Jianlong , Gu Lianchao , Zhong Mingqiang
Published: July 2008

To have an improved insight about the compatibilization effect of organoclay on immiscible polymers, two different organoclays and preparation techniques were chosen to prepare polyamide6 (PA6)/polystyrene (PS)/organoclay ternary nanocomposites. The morphology analysis based on the results of X‐ray diffraction, transmission electron microscopy, and scanning electron microscopy demonstrated that the type of organoclay and preparation technique had a significant influence on the dispersion and distribution of organoclay in the polymer. It was concluded that blending PS/organoclay nanocomposite synthesized previously via in situ bulk polymerization, with PA6 can realize the full exfoliation of organoclay in the final ternarynanocomposite, while an intercalated structure was achieved by directly blending the three components. The distribution of organoclay could be controlled by tuning the surface property of clay, and hence the interfacial interaction between clay and the polymer matrix. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Effects of some solvents on the thermal and free‐volume properties of poly(4‐vinylpyridine) complexes
Authors: Mazroua A. , Gomaa E.
Published: July 2008

Modified poly(4‐vinylpyridine) (P4VP) and its complexes were prepared with different solvents such as benzene, toluene, and xylene as well as potassium chloride (KCl) and copper chloride (CuCl2). Fourier transform infrared spectroscopy, thermal analysis, and positron annihilation spectroscopy were used to investigate the properties of the modified P4VP and its complexes. It was concluded that complexes were formed between the polymer and solvents via quaternization of nitrogen in the ring with the solvents and also with KCl and CuCl2·2H2O. Furthermore, the modified P4VP–CuCl2 complexes were more stable than the modified P4VP–KCl complexes, and these complexes were more stable than the P4VP–solvent complexes. Ortho‐positronium components (τ3, I3) were used to estimate the nanoscale free‐volume hole size (Vf) and the free‐volume fraction (f %). The free‐volume hole size and its fractions depended on the addition of solvents and metals to the polymer. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Degradation and life prediction of a natural rubber engine mount compound
Authors: Ngolemasango Frederick E. , Bennett Martyn , Clarke Jane
Published: July 2008

To assess and predict the functional life of a natural rubber engine mount compound, the mechanical property changes were determined under accelerated aging conditions. The rubber was aged at temperatures ranging from 70 to 110°C for times ranging from 1 h to 5 weeks. Tensile and fatigue measurements were used to characterize the aging trends and mechanisms of the engine mount compound. With the time–temperature superposition approach, the activation energy was found to be about 98 kJ/mol for the elongation at break, 93 kJ/mol for the tensile strength, and 60 kJ/mol for the fatigue life. The tensile strength after aging for 13 weeks at 50°C was predicted to be 18.73 MPa, which was very close to the experimental value of 19.04 ± 2.25 MPa. With a 50% reduction in the tensile strength used as the failure criterion, it was predicted that the tensile strength of the engine mount compound would take 80 days to decrease by 50% at 70°C. At 23°C, it would last approximately 140 times (31 years) its lifetime at 70°C. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008