bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stochastic and Deterministic Decision in Cell Fate
Authors: Menn David J , Wang Xiao 
Published: April 2014

Abstract

From bacteria to mammals, individual cells from an isogenic population are able to assume roles resulting in phenotypic heterogeneity. The mechanisms used to make these cell fate decisions range from highly deterministic to essentially random. This wide range of behaviour springs from the interplay of intracellular molecular kinetics, the topologies of underlying gene regulator networks, epigenetic control mechanisms and cell–environment interactions. Cells utilise these factors to implement differentiation strategies such as developmental rigidity, which ensures the development of key structures in multicellular organisms, and bet hedging, the introduction of nongenetic variability to promote population fitness. Because decision‐making genes in natural systems are integrated with myriad other pathways, they can be difficult to study on their own. Synthetic biology offers a means to study cell differentiation
in vivo
in a manner separated from normal cellular functions.

Key Concepts:

Gene expression is an inherently stochastic process.

Despite stochastic gene expression, differentiation can proceed deterministically.

Other cell fate decisions are random due to stochastic gene expression.

Gene network topologies are employed to attenuate or increase the effects of noise.

The field of synthetic biology is uniquely suited for exploring the complex interactions that inform cell decisions.
Genetic Influences on Male Homosexuality
Authors: Camperio Ciani Andrea S 
Published: April 2014

AbstractSexual orientation, identity and desire is the final product of complex interactions between factors such as genetic influences, epigenetic, developmental pathways, both prenatal such as sex hormones, including the maternal factors acting on the foetus, and postnatal factors including shared environmental influences such as family education, social and cultural influences, and nonshared environmental influence such as unique personal experiences. Male homosexuality poses an evolutionary dilemma as it entails reduced fitness but is nevertheless, in part, influenced by genetic factors. Examining the causes of homosexuality the author investigates the Darwinian dilemma as to why genetic factors that influence homosexual nonreproductive behaviour can be maintained in the population without disappearing as expected. Sexually antagonistic selection can explain male homosexuality. A sexually antagonistic model with genetic factors partially linked to X chromosome by increasing fecundity in females and influencing homosexuality in males could be selectively balanced in the population and explain all the peculiarity of male homosexuality.Key Concepts:Homosexuality is a volatile concept that varies with culture, history and traditions. Besides a difficulty in its definition even assessing its distribution across populations poses problems of reliability still unresolved. Basically, we still cannot claim that we know the actual distribution of human homosexuality.The homosexual phenotype is a complex set of emotion, behaviour and feelings influenced by a multiplicity of factors, environmental, developmental and genetic. The search of a single cause to explain the whole complexity of human homosexual phenotype seems arrived to an end.In homosexuals, genetic influence interacts with a multitude of environmental, familiar, early experiences or prenatal effects such as hormonal influences, stress or immune reactions by the mother, and other biological factors such as genomic, zygotic drive and epigenetics.Kin selection and avuncularity is a possibility that could compensate for the reduced fecundity of homosexuals, but most researches did not find any evidence of specific homosexual behaviour in modern society, which could promote close kin fecundity.The partial influence of genetic factors on homosexuality poses an interesting Darwinian conundrum which might be resolved by a sexually antagonistic selection mechanism.A sexually antagonistic selection mechanism suggests that the reduced fecundity of male homosexuals is balanced by the effect of the same genetic factors that promote fecundity in the maternal line females, thus balancing the effects on fitness and maintaining male homosexuality in the population.
Changing Building Sites: Industrialisation and Automation of the Building Process
Authors: Bock Thomas , Langenberg Silke 
Published: April 2014

AbstractThe introduction of robotics in construction is part of a much longer history of industrialisation and automation on the building site. Thomas Bock of the Technical University of Munich and Silke Langenberg of the University of Applied Sciences, Munich, highlight how the Industrial Revolution and the development of a transport infrastructure in the 18th and 19th centuries in Europe first triggered the shift in the building trade from a largely localised industry into a national and mechanised one, leading to the highly advanced automated construction techniques that continue to be developed in Japan and other Asian countries to this day.
In‐Situ Fabrication: Mobile Robotic Units on Construction Sites
Authors: Helm Volker 
Published: April 2014

AbstractEnabling the robotic fabrication of building elements directly on a construction site, in‐situ fabrication is a radical and novel approach to the application of digital fabrication in architecture. Volker Helm of ETH Zurich describes how an on‐site unit, developed with Fabio Gramazio and Matthias Kohler in the Architecture and Digital Fabrication department at the university, offers the first‐ever generic robot with applications in a wide range of processes, providing the means of investigating the requirements and capacities involved in non‐standardised fabrication.
Machines for Rent: Experiments by New‐Territories
Authors: Roche François , Lacadée Camille 
Published: April 2014

AbstractRobots have captured the popular imagination like no other technology, fuelling science‐fiction narratives in novels, art and film. Here, in a text by François Roche and Camille Lacadée of New‐Territories, ‘Machines for Rent’ are explored as a phenomenon that inhabits its own visionary realm, becoming a fertile field for experimentation. These fantastical mechanical creatures are visualised in exquisite drawings by François Roche and Stephan Henrich of New‐Territories.
Low Temperature Processing of Reaction‐Bonded Boron Carbide Composites
Authors: Frage Nachum , Hayun Shmuel , Dilman Helen , Dariel Moshe P. 
Published: April 2014

ABSTRACTThe present paper is concerned with the fabrication of fully dense B4C‐Mg, B4C‐AZ91 alloy, and B4C‐Mg,Si (eutectic) composites at a significantly lower (750–1000 °C) temperature range. The key feature of the novel approach is based on the Mg‐vapor atmosphere, under which the infiltration process is carried out. This approach has also been used to fabricate B4C‐Al composites at a low temperature. The microstructure and the mechanical properties of the composites are described and discussed. It was concluded that the formation of the deleterious aluminum carbide (Al4C3) depends on the presence of free carbon in the boron carbide powders. The suggested approach for low temperature fabrication of reaction bonded composites under Mg vapor can be further expanded to other boride and carbide phases.
Nucleophilic Reactivity of a Copper(II)–Superoxide Complex
Authors: Pirovano Paolo , Magherusan Adriana M. , McGlynn Ciara , Ure Andrew , Lynes Amy , McDonald Aidan R. 
Published: April 2014

AbstractMetal‐bound superoxide intermediates are often implicated as electrophilic oxidants in dioxygen‐activating metalloenzymes. In the nonheme iron α‐ketoglutarate dependent oxygenases and pterin‐dependent hydroxylases, however, FeIII–superoxide intermediates are postulated to react by nucleophilic attack on electrophilic carbon atoms. By reacting a CuII–superoxide complex (1) with acyl chloride substrates, we have found that a metal–superoxide complex can be a very reactive nucleophile. Furthermore, 1 was found to be an efficient nucleophilic deformylating reagent, capable of Baeyer–Villiger oxidation of a number of aldehyde substrates. The observed nucleophilic chemistry represents a new domain for metal–superoxide reactivity. Our observations provide support for the postulated role of metal–superoxide intermediates in nonheme iron α‐ketoglutarate dependent and pterin‐dependent enzymes.
Aza[6]helicene Platinum Complexes: Chirality Control of cis–trans Isomerism
Authors: Mendola Daniele , Saleh Nidal , Vanthuyne Nicolas , Roussel Christian , Toupet Loïc , Castiglione Franca , Caronna Tullio , Mele Andrea , Crassous Jeanne 
Published: April 2014

AbstractIt was serendipitously observed that cis‐[PtCl2(NCEt)PPh3] reacted differently with either racemic or enantiopure 4‐aza[6]helicene, giving respectively cis (racemic) and trans (enantiopure) [PtIICl2(4‐aza[6]helicene)PPh3] complexes. This unexpected reactivity is explained through a dynamic process (crystallization‐induced diastereoselective transformation) and enables a new aspect of reactivity in chiral transition‐metal complexes to be addressed.
Enhancing the air impermeability of a biobased poly(di‐isoamyl itaconate‐co‐isoprene) elastomer via the cocoagulation of latex and natural layered silicates
Authors: Yao Hui , Qiao He , Xing Qingyu , Gao Ning , Chu Junfeng , Zhang Liqun , Hua Kuo‐Chih , Kulig Joseph , Wang Runguo 
Published: April 2014

ABSTRACTThe gas‐barrier properties of elastomer are of particular importance, especially for airtight applications. Poly(di‐isoamyl itaconate‐co‐isoprene) (PDII) is a newly invented and respectable biobased elastomer, but the barrier properties of PDII and its composites with carbon black and silica are not satisfying at all. Because there are abundant ester groups in PDII macromolecules and these groups can contribute to the homogeneous dispersion of layer silicates, we applied layered silicates, including montmorillonite (MMT) and rectorite (REC), into the PDII matrix to improve the air impermeability. MMT/PDII and REC/PDII composites were prepared by a cocoagulation method, and the air impermeability of the PDII elastomer was highly improved. The smallest gas permeability index reached 1.7 × 10−17 m2 Pa−1 s−1 at an REC content of 80 phr; this implied a reduction of 85.5%. A comparison of the two types of silicate/PDII composites showed that the MMT/PDII composites had better properties at low filler contents, whereas the REC/PDII composites had better mechanical and gas‐barrier properties at high filler contents. Other structures and properties of the composites were investigated by X‐ray diffraction, transmission electron microscopy, and dynamic mechanical rheology. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40682.
Conductive polymer‐coated mesh films with tunable surface wettability for separation of oils and organics from water
Authors: An Jin , Cui Jin‐Feng , Zhu Zhao‐Qi , Liang Wei‐Dong , Pei Chun‐Juan , Sun Han‐Xue , Yang Bao‐Ping , Li An 
Published: April 2014

ABSTRACTHere, we reported the preparation of hydrophobic mesh films by coating conductive polymers including polyaniline and polypyrrole (PPy) onto stainless steel grid through a simple electrodepositing process by combination with modification of hydrophobic materials. The hydrophobic mesh films can be used for continual separation of oils and organics from water with high selectivity. Furthermore, mesh film with reversible switching wettability from hydrophobicity to hydrophilicity can be obtained by electrodepositing of PPy in the presence of perfluorooctanesulfonate dopants at different electric potential, which makes it possible to prepare functional mesh materials with remotely controllable surface wettability for selective absorption and purification. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40759.
Blends of poly(d,l‐lactide) with polyhedral oligomeric silsesquioxanes‐based biodegradable polyester: Synthesis, morphology, miscibility, and mechanical property
Authors: Wang Tianqiang , Ding Jing , Li Jiamin , Liu Yu , Hao Jianyuan 
Published: April 2014

ABSTRACTA highly branched hybrid copolymer based on polyhedral oligomeric silsesquioxane (POSS) was designed to improve the brittleness of poly(d,l‐lactide) (PDLLA). The toughening material was synthesized using POSS‐OH as the core, which initiated the ring‐opening polymerization of ε‐caprolactone and d,l‐lactide sequentially to form the highly branched POSS‐g‐poly (ε‐caprolactone)‐b‐poly(d,l‐lactide) (POSS‐g‐PCL‐b‐PLA) copolymer with eight PCL‐b‐PLA arms. The POSS‐g‐PCL‐b‐PLA copolymer had a very good dispersion in the PDLLA matrix with the size of microdomains smaller than 1 µm when added at a low content below 10 wt %. In related to the nano‐scale size of microdomains in the blends, the crystallinity of PCL blocks was significantly suppressed. Thus, the addition of POSS‐g‐PCL‐b‐PLA is very effective to improve the roughness of the matrix polymer when added at a low content. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40776.
Processing of multilayered filament composites by melt blown spinning
Authors: Hassounah Ibrahim A. , Rowland William C. , Sparks Stephanie A. , Orler Edward B. , Joseph Eugene G. , Camelio Jaime A , Mahajan Roop L. 
Published: April 2014

ABSTRACTNewly designed layer multiplying blocks are introduced in the process line of a melt blown spinning machine. The layer multiplying blocks have the capability to produce filament composites up to 1025 layers. Multilayer filament composites of polypropylene (PP) with poly(caprolactone) (PCL), a water soluble polyester or poly(l‐lactic acid) are successfully produced in the form of nonwovens. Selected samples of PP/PCL are delaminated using the following methods: semi‐crystalline PP/PCL samples are soaked in chloroform and agitated, and amorphous PP/PCL samples are subjected to mechanical stress in the axial spinning direction. Results show the possibility to create thin ribbons with extremely high surface area. The produced nonwovens and ribbons are characterized by field emission scanning electron microscopy and by differential scanning calorimetry. The extremely high surface area ribbons can be applied in different fields where high surface area is required, such as filtration, energy applications, catalysis, or tissue engineering. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40786.
Novel electrically conducting polyurethanes with oligoanilines: Synthesis, conductivity, and electrochemical properties
Authors: Arukula Ravi , Thota Appa Rao , Rao Chepuri R. K. , Narayan Ramanuj , Sreedhar B. 
Published: April 2014

ABSTRACTNew class of conducting polyurethanes (CPUs) containing oligoanilines, namely tetraaniline (TAni) or trianiline (TriAni), in the backbone have been synthesized and characterized by formal spectral techniques. The unique properties of these CPUs, viz., electronic conductivity and electrochemical activity arising from the presence of oligoaniline units have been evaluated. The basic polyurethane backbone is derived from toluene diisocyanate, isophorone diisocyanate or hexamethylene diisocyanate, and polypropylene glycols of molecular weight 425 and 2000. In the first category of polyurethanes, the prepolymers obtained from the above reactants were chain terminated by TAni in emeraldine base oxidation state. The conductivity of these CPUs films ranged from 1.2 × 10−5 to 1.77 × 10−3 S cm−1. These polymers showed lower conductivity due to the presence of nonconjugated polyurethane segments. These CPUs exhibited slightly different electrochemical activity than that of TAni. The second category of CPUs is obtained from prepolymers by chain extension with TriAni. The conductivity of these polymers is similar to the TAni analogues but are electrochemically inactive. The anticorrosion properties of two of these polymers have also been evaluated in this study. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40794.
Synthesis of a Glycopeptide Vaccine Conjugate for Induction of Antibodies Recognizing O‐Mannosyl Glycopeptides
Authors: Yu Jin , Westerlind Ulrika 
Published: April 2014

AbstractIn spite of the clear importance of protein O‐mannosylation in brain glycobiology, tools are lacking for specific detection, enrichment, and identification of proteins containing these modifycations. We envisioned inducing antibodies that specifically recognize O‐mannose glycans on proteins and peptides. With this in mind, we prepared a glycopeptide vaccine construct containing the N‐acetyllactosamine‐extended mannose motif Galβ1‐4GlcNAcβ1‐2ManαThr, found as a common core structure on almost all mammalian O‐mannosyl glycoproteins identified. O‐mannose glycosylated amino acid building blocks and the corresponding glycopeptides were prepared by chemical synthesis and then conjugated to an immune carrier protein. After administration of the synthetic vaccine into rabbits, strong immune responses were obtained. Further evaluation by ELISA neutralization experiments and glycopeptide microarrays showed that the induced antibodies were highly specific to the glycopeptide antigen.
Feasibility and safety of transradial coronary interventions using a 6.5‐F sheathless guiding catheter in patients with small radial arteries
Authors: Cheaito Radi , Benamer Hakim , Hovasse Thomas , Tritar Amine , Hage Fouad , Garot Philippe , Lefèvre Thierry , Unterseeh Thierry , Chevalier Bernard , Morice Marie‐Claude , Louvard Yves 
Published: April 2014

ObjectivesThis study investigated the feasibility and the safety of using a 6.5‐French sheathless guide catheter in patients with small radial arteries.BackgroundThe small size of radial arteries is a limitation of transradial coronary intervention. A new sheathless guiding catheter with a diameter almost 2‐Fr smaller than conventional sheaths and a full‐length hydrophilic coating has been introduced.MethodsA total of 148 patients from three French hospitals were consecutively enrolled from March 2009 to February 2012. They underwent transradial approach (TRA) for percutaneous coronary interventions (PCI) using the 6.5‐F ASAHI sheathless Eaucath guiding catheter system.ResultsAmong the 148 patients enrolled, 95 were females (64%), and 183 lesions were treated. Procedural success rate was 100%. Thirteen patients (9%) underwent same‐procedure multivessel interventions for the right and left coronary artery. Among the group of 46 patients undergoing bifurcation PCI, 35 (76%) bifurcated lesions were treated with a kissing balloon technique, one patient had a saphenous vein bypass graft lesion requiring filter wire placement prior to intervention, nine (6.1%) patients required rotational atherectomy, thrombus‐aspiration catheters were used in 19 (12.8%) patients, fractional flow reserve (FFR)‐guided PCI in 10 (6.7%) patients, alcohol septal ablation in three (2%) patients. Ten (6.7%) cases of chronic total occlusion were successfully treated in nine (6.1%) patients using the hydrophilic catheter. No radial artery site complications was noted.ConclusionThe use of sheathless guiding catheters is a safe, effective method for PCI via TRA in small radial arteries without catheter‐related complications. © 2015 Wiley Periodicals, Inc.
Palladium(II)/Polyoxometalate‐Catalyzed Direct Alkenylation of Benzofurans under Atmospheric Dioxygen
Authors: Huang Qiufeng , Ke Shaojia , Qiu Lin , Zhang Xiaofeng , Lin Shen 
Published: April 2014

AbstractAn efficient and selective C2 alkenylation of benzofurans was performed by using Pd(OAc)2 combined with a catalytic amount of 11‐molybdovanadophosphoric acid (H4PMo11VO40) under an atmosphere of dioxygen. N‐Acetylglycine (Ac‐Gly‐OH) was observed to be an effective additive for the olefination reaction.
Highly Efficient Reversible Hydrogenation of Carbon Dioxide to Formates Using a Ruthenium PNP‐Pincer Catalyst
Authors: Filonenko Georgy A. , van Putten Robbert , Schulpen Erik N. , Hensen Emiel J. M. , Pidko Evgeny A. 
Published: April 2014

AbstractThe use of hydrogen as a fuel requires both safe and robust technologies for its storage and transportation. Formic acid (FA) produced by the catalytic hydrogenation of CO2 is recognized as a potential intermediate H2 carrier. Herein, we present the development of a formate‐based H2 storage system that employs a Ru PNP‐pincer catalyst. The high stability of this system allows cyclic operation with an exceptionally fast loading and liberation of H2. Kinetic studies highlight the crucial role of the base promoter, which controls the rate‐determining step in FA dehydrogenation and defines the total H2 capacity attainable from the hydrogenation of CO2. The reported findings show promise for the development of practical technologies that use formic acid as a hydrogen carrier.
Rational Design, Synthesis, and Evaluation of Tetrahydroxamic Acid Chelators for Stable Complexation of Zirconium(IV)
Authors: Guérard François , Lee Yong‐Sok , Brechbiel Martin W. 
Published: April 2014

AbstractMetals of interest for biomedical applications often need to be complexed and associated in a stable manner with a targeting agent before use. Whereas the fundamentals of most transition‐metal complexation processes have been thoroughly studied, the complexation of ZrIV has been somewhat neglected. This metal has received growing attention in recent years, especially in nuclear medicine, with the use of 89Zr, which a β+‐emitter with near ideal characteristics for cancer imaging. However, the best chelating agent known for this radionuclide is the trishydroxamate desferrioxamine B (DFB), the ZrIV complex of which exhibits suboptimal stability, resulting in the progressive release of 89Zr in vivo. Based on a recent report demonstrating the higher thermodynamic stability of the tetrahydroxamate complexes of ZrIV compared with the trishydroxamate complexes analogues to DFB, we designed a series of tetrahydroxamic acids of varying geometries for improved complexation of this metal. Three macrocycles differing in their cavity size (28 to 36‐membered rings) were synthesized by using a ring‐closing metathesis strategy, as well as their acyclic analogues. A solution study with 89Zr showed the complexation to be more effective with increasing cavity size. Evaluation of the kinetic inertness of these new complexes in ethylenediaminetetraacetic acid (EDTA) solution showed significantly improved stabilities of the larger chelates compared with 89Zr‐DFB, whereas the smaller complexes suffered from insufficient stabilities. These results were rationalized by a quantum chemical study. The lower stability of the smaller chelates was attributed to ring strain, whereas the better stability of the larger cyclic complexes was explained by the macrocyclic effect and by the structural rigidity. Overall, these new chelating agents open new perspectives for the safe and efficient use of 89Zr in nuclear imaging, with the best chelators providing dramatically improved stabilities compared with the reference DFB.
Chemical and Toxicological Investigations of a Previously Unknown Poisonous European Mushroom Tricholoma terreum
Authors: Yin Xia , Feng Tao , Shang Jian‐Hua , Zhao Yun‐Li , Wang Fang , Li Zheng‐Hui , Dong Ze‐Jun , Luo Xiao‐Dong , Liu Ji‐Kai 
Published: April 2014

AbstractThe established tradition of consuming and marketing wild mushrooms has focused attention on mycotoxicity, which has become a global issue. In the present study, we describe the toxins found in a previously unknown poisonous European mushroom Tricholoma terreum. Fifteen new triterpenoids terreolides A–F (1–6) and saponaceolides H–P (8–16) were isolated from the fruiting bodies of the toxic mushroom T. terreum. Terreolides A–C (1–3) possessed a unique 5/6/7 trioxaspiroketal system, whereas terreolides D–F (4–6) possessed an unprecedented carbon skeleton. Two abundant compounds in the mushroom, saponaceolide B (7) and saponaceolide M (13), displayed acute toxicity, with LD50 values of 88.3 and 63.7 mg kg−1 when administered orally in mice. Both compounds were found to increase serum creatine kinase levels in mice, indicating that T. terreum may be the cause of mushroom poisoning ultimately leading to rhabdomyolysis.