bluuebunny/crossref_metadata_2025 huggingface dataset:
High Thermoelectric Figure of Merit in PbTe Alloys Demonstrated in PbTe–CdTe
Authors: Pei Yanzhong , LaLonde Aaron D. , Heinz Nicholas A. , Snyder G. Jeffrey
Published: April 2012

PbTe alloys have been the most efficient materials for thermoelectric power generation since the 1950s. In addition to the observed lattice thermal conductivity reduction by alloy scattering, recent efforts targeting electronic‐transport enhancement through band structure engineering have demonstrated a design route to achieve extraordinary thermoelectric performance. Guided by these recent results, the current work discusses the influence of alloying CdTe in p‐type PbTe where the solubility is strongly temperature‐dependent. Beneficial changes to the band structure and effective scattering of phonons are concurrently inferred when the PbTe–CdTe precipitate composite is expected to become a solid solution at high temperature, enhancing the peak thermoelectric figure of merit to ~1.7. This work emphasizes the importance of solid solution alloys of PbTe for thermoelectric power‐generation applications and also provides an upper limit of about 1 micrometer to the average distance between interfaces above which phonon scattering by composite interfaces is ineffectual.
Attenuation of vagal recovery during sleep and reduction of cortisol/melatonin ratio in late afternoon associate with prolonged daytime sleepiness among media workers with irregular shift work
Authors: Lindholm Harri , Sinisalo Juha , Ahlberg Jari , Hirvonen Ari , Hublin Christer , Partinen Markku , Savolainen Aslak
Published: April 2012

Background

Media work is characterized by information flow, deadlines, and 24/7 alertness. Good recovery prevents stress‐related disorders.

Methods

The standardized questionnaire included items about health, health habits, sleep, work conditions, and work stress. Recordings of 24‐hr heart rate variability (HRV) and four salivary samples for cortisol and melatonin levels were analyzed from 70 randomly selected workers with irregular shift work, and 70 workers with normal daytime work.

Results

Irregular shift work increased the risk of insufficient recovery when compared to normal daytime work (OR 2.0; P < 0.05). In the group of workers with insufficient subjective recovery, HRV was attenuated (P < 0.05) during the early hours of night, and cortisol/melatonin ratio was decreased (P < 0.05) in the afternoon.

Conclusions

Physiological changes underlying subjective feelings of insufficient recovery are measurable. Attenuated HRV during sleep reflects prolonged sympathetic drive and/or impaired parasympathetic recovery. Interactions between cortisol and melatonin hormones might be involved in the development of chronic exhaustion. Am. J. Ind. Med. 55:643–649, 2012. © 2012 Wiley Periodicals, Inc.
Preparation and characterization of a novel once‐daily formulation of diltiazem using arabinogalactan as a channeling agent
Authors: Avramoff Avi , Khan Wahid , Mizrahi Boaz , Domb Abraham J.
Published: April 2012

The aim of the present study was to develop a once‐daily, delayed controlled release formulation for diltiazem. Developed formulation consists of two coated tablets inserted into a capsule; the first tablet is intended to produce a fast release profile, while the second tablet with a unique controlling membrane containing arabinogalactan as a channeling agent was designed to achieve a delayed controlled release profile for diltiazem. The in vitro characteristic of formulation was determined in terms of the surface morphology of the coated tablet, and the impact of the different polysaccharide in coating on the dissolution and in vitro drug release. Arabinogalactan was found to be most appropriate channeling agent to control in vitro drug release. When tested in buffer (pH 6.8) the formulation produced a desired delayed controlled release dissolution profile for over 24 h. Surface morphology of the coating film clearly demonstrated channeling formation on contact with the media. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Preparation and characterization of new organosoluble polyamides with good thermal properties containing photosensitive group in the main chain
Authors: Hajibeygi Mohsen , Shabanian Meisam
Published: April 2012

In this article, we have successfully synthesized a new dicarboxylic acid, from the two step reactions. At first 4,4′‐bis(1,2‐diphenoxyethane) dialdehyde was synthesized from 1,2‐dibromoethane and 4‐hydroxybenzaldehyde , then 4,4′‐bis(1,2‐diphenoxyethane) diacrylic acid was synthesized from 4,4′‐bis(1,2‐diphenoxyethane) dialdehyde and malonic acid in a solvent free reaction. Four new organosoluble and thermally stable polyamides (PAs) with good inherent viscosities containing photosensitive groups were synthesized from the direct polycondensation reaction of 4,4′‐bis(1,2‐diphenoxyethane) diacrylic acid with four various aromatic diamines containing photosensitive group, by two different methods such as direct polycondensation in a medium consisting of N‐methyl‐2‐pyrrolidone (NMP)/triphenyl phosphite (TPP)/calcium chloride (CaCl2)/pyridine (Py) and direct polycondensation in a tosyl chloride (TsCl)/pyridine (Py)/N,N‐dimethylformamide (DMF) system. All of the above polymers were fully characterized by 1H‐NMR, FTIR, gel permeation chromatography (GPC), elemental analysis, inherent viscosity, solubility tests, UV–vis spectroscopy, differential scanning calorimeter (DSC), thermogravimetric analysis (TGA). The resulted polyamides (PAs) have showed admirable good inherent viscosities, thermal stability and solubility. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Surfactant‐modified feldspar: Isotherm, kinetic, and thermodynamic of binary system dye removal
Authors: Yazdani Maryam , Mahmoodi Niyaz Mohammad , Arami Mokhtar , Bahrami Hajir
Published: April 2012

In this article, surface modification of feldspar using hexadecyltrimethyl ammonium bromide (HDTMA) and its dye removal ability in single and binary systems was studied. Acid Black 1 (AB1) and Acid Red 14 (AR14) were used as model dyes. The monocomponent Langmuir isotherm model was applied to experimental data and the isotherm constants were calculated for both dyes. The monolayer coverage capacities of surfactant‐modified feldspar (HDTMA‐feldspar) for AB1 and AR14 dyes in single solution system were found as 6.369 mg/g and 3.984 mg/g, respectively. It was observed that the equilibrium uptake amounts of AB1 and AR14 dye in binary mixture onto sorbent decreased with increasing concentrations of the other dye resulting in their antagonistic effect. Equilibrium adsorption for binary systems was analyzed by using the Extended Langmuir and Jain and Snoeyink Modified Extended Langmuir models. The rate of kinetic processes of single and binary dye systems onto adsorbent was described by using two kinetics adsorption models. The pseudo‐second‐order model was the best choice among the kinetic models to describe the adsorption behavior of single and binary dyes onto HDTMA‐feldspar. Thermodynamic parameters showed that dye adsorption on HDTMA‐feldspar were exothermic and unspontaneous in nature. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Relaxation behavior of poly(lactic acid)/poly(butylene succinate) blend and a new method for calculating its interfacial tension
Authors: Xu Lin‐Qiong , Huang Han‐Xiong
Published: April 2012

The biomass‐based blend of 80/20 (w/w) poly(lactic acid)/poly(butylene succinate) (PLA/PBS) is prepared using an extruder. The prepared blend shows a typical droplet‐matrix morphology. The relaxation behavior of the blend is investigated in terms of storage modulus, loss tangent, and Cole–Cole plots. In the low frequency region, the blend exhibits higher elastic indices than the pure components on the storage modulus and loss tangent curves, and remarkable deviation from a semicircular shape on the Cole–Cole plot. These features are thought to arise from the relaxation of the deformed droplets. The loss tangent curve is more sensitive to the relaxation behavior of the deformed droplets than the storage modulus curve. Moreover, the complex viscosity of the blend is separated into real and imaginary parts to further analyze its relaxation behavior. Three relaxation times for the blend are defined on the curve of the imaginary part of the viscosity. It is demonstrated that the reciprocal of the frequency corresponding to the peak in the low frequency region on the imaginary part curve is equal to the longest relaxation time of the blend obtained from the storage modulus curve. Based on this result, a new method is proposed to calculate the interfacial tension between the PLA and PBS in the blend, which is 3.7 mN/m. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Fiber‐reinforced nanopigmented poly(methyl methacrylate) as improved denture base
Authors: Moreno‐Maldonado V. , Acosta‐Torres L. S. , Barceló‐Santana F. H. , Vanegas‐Lancón R. D. , Plata‐Rodríguez M. E. , Castaño V. M.
Published: April 2012

Nanopigmented and fiber‐reinforced poly (methyl methacrylate) (PMMA) were synthesized for denture bases, by incorporating E‐glass fibers, flock fibers, or polyethylene fibers into the PMMA powder formulation to improve the flexural behavior and porosity; decreasing the Candida albicans adherence and being noncytotoxic. The commercial acrylic resin, Lucitone 199 was used as a control group. Scanning electron microscopy analysis was performed to the PMMA particles and the reinforcing fibers. Flexural strength increased by adding E‐glass fibers in the PMMA powder as compared to flock and polyethylene fibers. The reinforced PMMA with flock fibers showed the lower porosity even smaller than Lucitone 199. The synthesized PMMA and the fiber reinforced nanopigmented PMMA groups reduced significantly the C. albicans adherence when compared to the commercial acrylic resin. All the tested groups were found to be nontoxic materials after being in contact with mouse fibroblast culture during 24 h, showing that these novel nanostructured composites are suitable for producing adequate and nontoxic reinforced materials with antimicrobial properties for dentistry applications. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Preparation and characterization of cellulose‐coated chitosan beads with improved strength and acid resistivity
Authors: Duan Jiangjiang , Wang Yue , Wang Yudi , Xiong Xiaopeng
Published: April 2012

A new chitosan bead was successfully prepared by simply dropping acidic chitosan solution into 0.5 wt % alkaline cellulose solution. The X‐ray photoelectron spectroscopy analysis and the scanning electron microscope observation indicate that thin layer of cellulose was coated on the chitosan bead to have strong interaction with inner chitosan. Therefore, the bead reveals porous microstructure of regenerate cellulose in the surface. Owing to the cellulose coating, the bead displays improved mechanical properties and acid resistance. The adsorption of Fe3+ onto the new chitosan beads was investigated in detail, and the results show that the cellulose coating has little influence on the adsorption of the chitosan. Therefore, this study provides a novel method to expand the application of chitosan by coating with an acid‐insensitive polymer. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Elution of polymers from poly(vinyl alcohol) cast gels with different degrees of polymerization and hydrolysis
Authors: Sasaki Saori , Otsuka Emiko , Hirashima Yumiko , Suzuki Atsushi
Published: April 2012

Poly(vinyl alcohol) (PVA) gels physically crosslinked by microcrystallites were prepared by a cast‐drying method using PVA powders with different degrees of polymerization (nDP) between 300 and 2400 and hydrolysis (rDH) between 79.5 and 98.5 mol %. Polymer elution of gels in a limited amount of water was investigated by measuring the total carbon in the outer water by a total organic carbon analyzer. As a result, polymer elution was detected for all gels, the total amount of which depended on both nDP and rDH. In the cases of lower nDP and higher rDH, the gel became opaque and cracks were observed on the surface during a simple swelling process. On the other hand, polymers dissolved without cracks in the cases of higher nDP and lower rDH. These results are discussed on the basis of the network microstructure of the dried states before and after the polymer elution. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Investigation of the effect of double‐walled carbon nanotubes on the curing reaction kinetics and shear flow of an epoxy resin
Authors: El Sawi Ihab , Olivier Philippe A. , Demont Philippe , Bougherara Habiba
Published: April 2012

In this article, the effect of combined temperature‐concentration and shear rate conditions on the rheology of double‐walled carbon nanotubes (DWCNTs)/RTM6‐Epoxy suspension was investigated to determine the optimum processing conditions. The rheological behavior and cure kinetics of this nanocomposite are presented. Cure kinetics analysis of the epoxy resin and the epoxy resin filled with DWCNTs was performed using Differential Scanning Calorimeter (DSC) and parameters of the kinetics model were compared. The DWCNTs have an acceleration effect on the reaction rate of the epoxy resin but no significant effect is noted on the glass transition temperature of the epoxy resin. This study reveals that the effect of shear‐thinning is more pronounced at high temperatures when DWCNTs content is increased. In addition, the steady shear flow exhibits a thermally activated property above 60°C whereas the polymer fluid viscosity is influenced by the free volume and cooperative effects when the temperature is below 60°C. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Study of physicochemical properties of two current commercial dental self‐curing resin composites
Authors: Sideridou Irini D. , Vouvoudi Evangelia C. , Bourdouni Konstantina A.
Published: April 2012

The aim of the present work is the study of some physicochemical properties of two current commercial dental self‐curing two component composites, i.e., of Concise™ (3M™, Dental Products, St. Paul, USA), and Alfacomp (VOCO GmbH, Germany). Based on their filler type Concise is characterized as “conventional” or “macrofilled” composite and Alfacomp as “hybrid.” The resin matrix of Concise is a copolymer of 2‐bis[4‐2‐hydroxy‐3‐(methacryloxy)‐propyl]phenyl propane (Bis‐GMA)/triethyleneglycol dimethacrylate, while that of Alfacomp a homopolymer of Bis‐GMA. The composites were prepared in accordance with the manufacturers' instructions by mixing equal amounts of the two components at room temperature. The degree of conversion of double bonds of resin matrix during curing was determined in thin film of composites using FTIR transmission spectroscopy. The degree of conversion of Concise and Aflacomp was found to be correspondingly (73.63 ± 4.33)% and (47.75 ± 1.80)% after a day‐polymerization. Sorption, solubility, and volumetric change were determined after storage of composites in water or ethanol/water solution 75 vol % at 37°C (a good food/oral simulating fluid) for 30 days. These properties for both composites were higher in ethanol/water solution than in water. Also these properties for Concise were lower than those for Alfacomp in both liquids. Thermal stability of composites was studied by thermogravimetric analysis which performed in air atmosphere from 50 to 800°C. This analysis of composites showed the degradation of their resin matrix in three steps. The organic resin content of Concise was found to be 18.0% w/w and that of Alfacomp 20.1% w/w. Concise showed generally better properties than Alfacomp. This behavior must due to the differences in the chemical structure of the organic resin matrix and the type of inorganic filler. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Thermodynamic parameters of poly(ethylene glycol) from dielectric relaxation studies
Authors: Sannaningannavar F. M. , Navati B. S. , Ayachit N. H.
Published: April 2012

Thermodynamic parameters, like change in free energy of activation (ΔG), enthalpy of activation (ΔH), and entropy of activation (ΔS) of poly(ethylene glycol) with average molecular mass 400 Delton (PEG 400) in dilute solution of benzene were computed on the basis of theory of Eyring rate process. To estimate these, the dielectric relaxation time (τ), determined at various temperatures adopting Whiffen and Thompson model have been used. X‐band microwave bench working at 9.59 GHz was employed to find temperature dependent real part ε′ of the complex dielectric permittivity ε* and dielectric loss ε″. The values of these ε′ and ε″ are used to find τ values. Based on the results reported, the relaxation behavior of the stated polymer in nonpolar solvent is discussed. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Lamellarins as Inhibitors of P‐Glycoprotein‐Mediated Multidrug Resistance in a Human Colon Cancer Cell Line
Authors: Plisson Fabien , Huang Xiao‐Cong , Zhang Hua , Khalil Zeinab , Capon Robert J.
Published: April 2012

Chemical analysis of a Didemnum sp. (CMB‐01656) collected during scientific Scuba operations off Wasp Island, New South Wales, yielded five new lamellarins A1 (1), A2 (2), A3 (3), A4 (4) and A5 (5) and eight known lamellarins C (6), E (7), K (8), M (9), S (10), T (11), X (12) and χ (13). Analysis of a second Didemnum sp. (CMB‐02127) collected during scientific trawling operations along the Northern Rottnest Shelf, Western Australia, yielded the new lamellarin A6 (14) and two known lamellarins G (15) and Z (16). Structures were assigned to 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 on the basis of detailed spectroscopic analysis with comparison to literature data and authentic samples. Access to this unique library of natural lamellarins (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16) provided a rare opportunity for structure–activity relationship (SAR) investigations, probing interactions between lamellarins and the ABC transporter efflux pump P‐glycoprotein (P‐gp) with a view to reversing multidrug resistance in a human colon cancer cell line (SW620 Ad300). These SAR studies, which were expanded to include the permethylated lamellarin derivative (17) and a series of lamellarin‐inspired synthetic coumarins (19, 20, 21, 22, 23, 24) and isoquinolines (25, 26), successfully revealed 17 as a promising new non‐cytotoxic P‐gp inhibitor pharmacophore.
1‐Bromo‐2‐(cyclopropylidenemethyl)benzene: A Useful Building Block in the Palladium‐Catalyzed Reaction of 2‐Alkynylbenzenamine
Authors: Li Shaoyu , Luo Yong , Wang Xiaocong , Guo Minjie , Wu Jie
Published: April 2012

A novel palladium‐catalyzed domino reaction of 1‐bromo‐2‐(cyclopropylidenemethyl)benzene and 2‐alkynylbenzenamine is reported, which generates 2‐(naphthalen‐2‐yl)benzenamines and 5H‐indeno[1,2‐c]quinolines via 6‐endo and 5‐exo cyclization, respectively. The regioselectivity for the final outcome can be affected by phosphine and N‐heterocyclic carbene ligands.
Challenges, Coping Strategies, and Unmet Needs of Families with a Child with Autism Spectrum Disorder in Goa, India
Authors: Divan Gauri , Vajaratkar Vivek , Desai Miraj U. , Strik‐Lievers Luisa , Patel Vikram
Published: April 2012

Autism Spectrum Disorders (ASD) are increasingly recognized in developing countries like India. However, little is known about the experiences of parents raising a child with ASD. This study aimed to describe the experiences of families in Goa, India with a view to understanding the unmet needs of families raising a child with ASD. Twenty in‐depth interviews and nine focus group discussions were carried out with families of children with ASD and key community stakeholders such as special educators, teachers, and parents of typically developing children. This qualitative data was triangulated to explore the experiences, life impact, and unmet needs of raising a child with ASD. Key findings suggest that raising a child with ASD puts a tremendous strain on families due to competing commitments, often leading to initial social withdrawal with later reintegration into social networks. Second, the impact is multidimensional, involving the personal sphere but also extending into the wider community with negative experiences of discrimination. Third, parents actively respond to these challenges through a range of approaches with help from existing and new social support networks and health care providers. Fourth, professionals from the health, education, and religious sectors have a low awareness of the unique needs of families living with ASD which leads to a considerable economic and emotional burden on families. Finally, as a consequence of these experiences, several unmet needs can be identified, notably for supporting increasingly isolated families and the limited access to multidisciplinary evidence‐based services for ASD. Autism Res 2012, 5: 190–200. © 2012 International Society for Autism Research, Wiley Periodicals, Inc.
Protein oxidation in Huntington disease
Authors: Sorolla M. Alba , Rodríguez‐Colman María José , Vall‐llaura Núria , Tamarit Jordi , Ros Joaquim , Cabiscol Elisa
Published: April 2012

Huntington disease (HD) is an inherited neurodegenerative disorder caused by expansion of CAG repeats in the huntingtin gene, affecting initially the striatum and progressively the cortex. Oxidative stress, and consequent protein oxidation, has been described as important to disease progression. This review focuses on recent advances in the field, with a particular emphasis on the identified target proteins and the role that their oxidation has or might have in the pathophysiology of HD. Oxidation and the resulting inactivation and/or degradation of important proteins can explain the impairment of several metabolic pathways in HD. Oxidation of enzymes involved in ATP synthesis can account for the energy deficiency observed. Impairment of protein folding and degradation can be due to oxidation of several heat shock proteins and Valosin‐containing protein. Oxidation of two enzymes involved in the vitamin B6 metabolism could result in decreased availability of pyridoxal phosphate, which is a necessary cofactor in transaminations, the kynurenine pathway and the synthesis of glutathione, GABA, dopamine and serotonin, all of which have a key role in HD pathology. In addition, protein oxidation often contributes to oxidative stress, aggravating the molecular damage inside the cell.
Gorgon and pathwalking: Macromolecular modeling tools for subnanometer resolution density maps
Authors: Baker Matthew L. , Baker Mariah R. , Hryc Corey F. , Ju Tao , Chiu Wah
Published: April 2012

The complex interplay of proteins and other molecules, often in the form of large transitory assemblies, are critical to cellular function. Today, X‐ray crystallography and electron cryo‐microscopy (cryo‐EM) are routinely used to image these macromolecular complexes, though often at limited resolutions. Despite the rapidly growing number of macromolecular structures, few tools exist for modeling and annotating structures in the range of 3–10 Å resolution. To address this need, we have developed a number of utilities specifically targeting subnanometer resolution density maps. As part of the 2010 Cryo‐EM Modeling Challenge, we demonstrated two of our latest de novo modeling tools, Pathwalking and Gorgon, as well as a tool for secondary structure identification (SSEHunter) and a new rigid‐body/flexible fitting tool in Gorgon. In total, we submitted 30 structural models from ten different subnanometer resolution data sets in four of the six challenge categories. Each of our utlities produced accurate structural models and annotations across the various density maps. In the end, the utilities that we present here offer users a robust toolkit for analyzing and modeling protein structure in macromolecular assemblies at non‐atomic resolutions. © 2012 Wiley Periodicals, Inc. Biopolymers 97: 655–668, 2012.
Quality attributes of recombinant therapeutic proteins: An assessment of impact on safety and efficacy as part of a quality by design development approach
Authors: Eon‐Duval Alex , Broly Hervé , Gleixner Ralf
Published: April 2012

Quality by Design (QbD) is a new approach to the development of recombinant therapeutic protein products that promotes a better understanding of the product and its manufacturing process. The first step in the QbD approach consists in identifying the critical quality attributes (CQA), i.e., those quality attributes of the product that have an impact on its clinical efficacy or safety. CQAs are identified through a science‐based risk assessment taking into consideration a combination of clinical and nonclinical data obtained with the molecule or other similar molecules or platform products, as well as the published literature. The purpose of this article is to perform a comprehensive review of the published literature, supporting an assessment of the impact on safety and efficacy of the quality attributes commonly encountered in recombinant therapeutic proteins, more specifically those produced in mammalian cell expression systems. Quality attributes generally observed in biopharmaceutical proteins including product‐related impurities and substances, process‐related impurities, product attributes, and contaminants are evaluated one by one for their impact on biological activity, pharmacokinetics and pharmacodynamics, immunogenicity, and overall safety/toxicity. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Popliteal vascular entrapment syndrome caused by variant lateral head of the gastrocnemius muscle leading to pulmonary artery embolism
Authors: Wang Maohua , Zhang Shiyi , Wu Xuejun , Jin Xing , Zhang Jingyong
Published: April 2012

A young man with popliteal vascular entrapment syndrome (PVES) presented with arterial occlusion, deep venous thrombosis (DVT), pulmonary artery embolism, and pulmonary hypertension. He received computer tomography (CT) and magnetic resonance imaging (MRI). Both CT and MRI showed that the left thrombosed popliteal vein and artery were entrapped by a variant lateral head of the gastrocnemius muscle. The anomalous slip originated from the lateral head of left gastrocnemius muscle and ended between the medial and lateral femoral condyles. PVES Type V was diagnosed. Compression of the popliteal vein without arterial compression can be explained by the more lateral location of the popliteal vein relative to the artery and its proximity to the lateral head of the gastrocnemius. Compression of the popliteal vein with arterial compression was found in this patient. Compression of popliteal vein and artery in this patient led to DVT and arterial occlusion. The case was the first reported case accompanied by popliteal vein and artery thrombosis caused by variant lateral head of the gastrocnemius muscle. Radiologists and doctors should continue to look for possible abnormalities in the popliteal fossa in young patients with peripheral vascular disease because early diagnosis of PVES allows better choices and outcomes of treatment. Clin. Anat. 25:986–988, 2012. © 2012 Wiley Periodicals, Inc.
The ancient Hellenic and Hippocratic origins of head and brain terminology
Authors: Panourias Ioannis G. , Stranjalis George , Stavrinou Lampis , Sakas Damianos E.
Published: April 2012

Corpus Hippocraticum, a collection of Hippocratic writings, is considered to be the first written monument of rationale medicine. This article focuses on a series of ancient Hellenic words which are cited in Hippocratic passages and have been adopted in current head and brain terminology either invariably, i.e., keeping their original meaning, or as component parts of newly formed terms. This study aims to demonstrate first that the deeper roots of current neuroanatomical terminology spread in Hippocratic writings and second, that ancient Hellenic remains a living language that would probably ever continue to play a catalytic role in the formation of neuroanatomical glossary by providing accurate, emblematic, and functional terms. Clin. Anat. 25:548–558, 2012. © 2012 Wiley Periodicals, Inc.
Anatomic study of the superficial sural artery and its implication in the neurocutaneous vascularized sural nerve free flap
Authors: Leclère Franck Marie , Eggli Simone , Mathys Lukas , Vögelin Esther
Published: April 2012

Combined extended nerve and soft tissue defects of the upper extremity require nerve reconstruction and adequate soft tissue coverage. This study focuses on the reliability of the free vascularized sural nerve graft combined with a fasciocutaneous posterior calf flap within this indication. An anatomical study was performed on 26 cadaveric lower extremities that had been Thiel fixated and color silicone injected. Dissection of the fasciocutaneous posterior calf flap involved the medial sural nerve and superficial sural artery (SSA) with its septocutaneous perforators, extended laterally to include the lateral cutaneous branch of the sural nerve and continued to the popliteal origin of the vascular pedicle and the nerves. The vessel and nerves diameter were measured with an eyepiece reticle at 4.5× magnification. Length and diameter of the nerves and vessels were carefully assessed and reported in the dissection book. A total of 26 flaps were dissected. The SSA originated from the medial sural artery (13 cases), the popliteal artery (12 cases), or the lateral sural artery (one case). The average size of the SSA was 1.4 ± 0.4 mm. The mean pedicle length before the artery joined the sural nerve was 4.5 ± 1.9 cm. A comitant vein was present in 21 cases with an average diameter of 2.0 ± 0.8 mm, in 5 cases a separate vein needed to be dissected with an average diameter of 3.5 ± 0.4 mm. The mean medial vascularized sural nerve length was 21.2 ± 8.9 cm. Because of inclusion of the vascularized part of the lateral branch of the sural nerve (mean length of 16.7 ± 4.8 cm), a total of 35.0 ± 9.6 cm mean length of vascularized nerve could be gained from each extremity. The free vascularized sural nerve graft combined with a fasciocutaneous posterior calf flap pedicled on the SSA offers a reliable solution for complex tissue and nerve defect. Clin. Anat. 26:903–910, 2013. © 2012 Wiley Periodicals, Inc.
Generation of RNA Molecules by a Base‐Catalysed Click‐Like Reaction
Authors: Costanzo Giovanna , Saladino Raffaele , Botta Giorgia , Giorgi Alessandra , Scipioni Anita , Pino Samanta , Di Mauro Ernesto
Published: April 2012

The problem of the abiotic origin of RNA from prebiotically plausible compounds remains unsolved. As a potential partial solution, we report the spontaneous polymerization of 3′,5′‐cyclic GMP in water, in formamide, in dimethylformamide, and (in water) in the presence of a Brønsted base such as 1,8‐diazabicycloundec‐7‐ene. The reaction is untemplated, does not require enzymatic activities, is thermodynamically favoured and selectively yields 3′,5′‐bonded ribopolymers containing as many as 25 nucleotides. We propose a reaction pathway on the basis of 1) the measured stacking of the 3′,5′‐cyclic monomers, 2) the activation by Brønsted bases, 3) the determination (by MALDI‐TOF mass spectrometry, by 31P NMR, and by specific ribonucleases) of the molecular species produced. The reaction pathway has several of the attributes of a click‐like reaction.
Middle‐of‐the‐night PCI does not affect subsequent day PCI success and complication rates by the same operator
Authors: Crudu Vitalie , Sartorius Jennifer , Berger Peter , Scott Thomas , Skelding Kimberly , Blankenship James
Published: April 2012

Objective

To determine the impact of percutaneous coronary interventions (PCI) performed during late‐night hours on next day PCI performance by the same interventional cardiologist.

Background

There is little data regarding the effects of sleep deprivation on interventional cardiologists performing PCIs.

Methods

All primary PCIs from January 1, 2005 to December 31, 2009 between 11 PM and 7 AM were identified. All PCIs performed during the subsequent work day by the same interventionists were included in the sleep‐deprived group. All other PCIs were included in the non‐sleep‐deprived group. Data were entered prospectively into the American College of Cardiology National Cardiovascular Data Registry (NCDR). The two groups were compared with respect to efficacy and safety endpoints.

Results

During the 5‐year period, 3,944 PCIs were performed by four operators, including 3,644 non‐sleep‐deprived cases and 167 sleep‐deprived cases. The two groups were similar with respect to demographics, comorbidities, and procedural characteristics. There were more intraprocedural deaths in the sleep‐deprived group (1.2% vs. 0.2%, P = 0.04); however, the adjusted odds ratio (OR) was nonsignificant (OR = 6.83, 95% confidence interval [CI] = 0.66–39.63, P = 0.11). Excessive bleeding at the arterial access site in the non‐sleep‐deprived group was more frequent (2.7% vs. 0%, P = 0.02). There were no differences in the combined safety or efficacy endpoints between the two groups.

Conclusion

In this single‐center study, we found no evidence that middle‐of‐the night procedures adversely affect safety or efficacy of procedures done the next day by the same operator. © 2012 Wiley Periodicals, Inc.
A Solid‐State Combustion Method towards Metallic Cu–ZnO Catalyst without Further Reduction and its Application to Low‐Temperature Methanol Synthesis
Authors: Shi Lei , Tan Yi‐sheng , Tsubaki Noritatsu
Published: April 2012

A series of Cu–ZnO catalysts were prepared by using a solid‐state combustion method with metal nitrates and citric acid. This method was simple, waste water free, and did not require a reduction step. If the precursors were burnt in an argon atmosphere, H2 and CH4 were emitted in the decomposition of metal citrate complexes and acted as reducing agents to yield metallic Cu from Cu2+ in the chelated compounds. Analysis of XRD patterns revealed that the precursors burnt at 523 K for 1 h in the argon atmosphere were converted into pure Cu species. TPR analysis of the burnt catalysts without further reduction illustrated that almost no hydrogen was consumed. However, a part of amorphous carbon and carboxylates were left in the burnt catalysts. Compared with formerly reported Cu–ZnO catalysts prepared by the sol–gel combustion method, the catalysts prepared by the solid‐state combustion method had higher activity and methanol selectivity.
Fabrication of Homogenous Polymer‐Zeolite Nanocomposites as Mixed‐Matrix Membranes for Gas Separation
Authors: Karkhanechi H. , Kazemian H. , Nazockdast H. , Mozdianfard M. R. , Bidoki S. M.
Published: April 2012

Interfacial void‐free mixed‐matrix membranes (MMMs) of polyimide (PI)/zeolite were developed using 13X and Linde type A nano‐zeolites and tested for gas separation purposes. Fabrication of a void‐free polymer‐zeolite interface was verified by the decreasing permeability developed by the MMMs for the examined gases, in comparison to the pure PI membrane. The molecular sieving effect introduced by zeolite 13X improved the CO2/N2 and CO2/CH4 selectivity of the MMMs. Separation tests indicated that the manufactured nanocomposite membrane with 30 % loading of 13X had the highest permselectivity for the gas pairs CO2/CH4 and CO2/N2 at the three examined feed pressures of 4, 8 and 12 atm.
Thiols Screened by the Neocarzinostatin Protein for Preserving or Detoxifying its Bound Enediyne Antibiotic
Authors: Chi Hung‐Wen , Huang Chun‐Chi , Chin Der‐Hang
Published: April 2012

Neocarzinostatin is an antibiotic chromoprotein produced by Streptomyces carzinostaticus. Its enediyne‐containing chromophore exhibits high DNA cleavage activity and belongs to one of the most potent categories of antitumor agents. The labile chromophore is readily inactivated by environmental thiols including the most abundant glutathione. How the microorganism preserves the secreted antibiotic and at the same time is immune to its toxicity are of interest. Site‐directed mutagenesis studies of the neocarzinostatin protein have shown that residues D33 and D99 play primary and secondary roles, respectively, in preserving neocarzinostatin from acidic glutathione whereas D79 and other residues around the opening of the binding cleft have an insignificant effect. Biothiol analyses revealed that cells of S. carzinostaticus produced no glutathione, but instead neutral mycothiol, which is known to serve functions analogous to glutathione. Mycothiol was the only neutral‐charged thiol produced by the organism; all other identified biothiols carried at least partial negative charges. When the bacteria were cultured under conditions that stimulated the biosynthesis of neocarzinostatin, the yield of mycothiol increased significantly, which suggests mycothiol‐dependent cellular detoxification. Treating neocarzinostatin samples with the cell extract that retained active sulfhydryls led to efficient drug inactivation, which indicates that mycothiol is allowed to approach the protein‐bound chromophore. The anionic side‐chains of D33 and D99 in the neocarzinostatin protein played two critical roles in a single thiol‐screening operation: Preserving the antibiotic for defense and survival by rejecting the ubiquitous glutathione through charge–charge repulsion in the outer‐cell environment and detoxifying the toxin in the inner‐cell body for self‐resistance by accepting the cell‐produced neutral mycothiol.
Archipelago architecture of the focal adhesion: Membrane molecules freely enter and exit from the focal adhesion zone
Authors: Shibata Akihiro C. E. , Fujiwara Takahiro K. , Chen Limin , Suzuki Kenichi G. N. , Ishikawa Yoshiro , Nemoto Yuri L. , Miwa Yoshihiro , Kalay Ziya , Chadda Rahul , Naruse Keiji , Kusumi Akihiro
Published: April 2012

The focal adhesion (FA) is an integrin‐based structure built in/on the plasma membrane, mechanically linking the extracellular matrix with the termini of actin stress fibers, providing key scaffolds for the cells to migrate in tissues. The FA was considered as a micron‐scale, massive assembly of various proteins, although its formation and decomposition occur quickly in several to several 10 s of minutes. The mechanism of rapid FA regulation has been a major mystery in cell biology. Here, using fast single fluorescent‐molecule imaging, we found that transferrin receptor and Thy1, non‐FA membrane proteins, readily enter the FA zone, diffuse rapidly there, and exit into the bulk plasma membrane. Integrin β3 also readily enters the FA zone, and repeatedly undergoes temporary immobilization and diffusion in the FA zone, whereas approximately one‐third of integrin β3 is immobilized there. These results are consistent with the archipelago architecture of the FA, which consists of many integrin islands: the membrane molecules enter the inter‐island channels rather freely, and the integrins in the integrin islands can be rapidly exchanged with those in the bulk membrane. Such an archipelago architecture would allow rapid FA formation and disintegration, and might be applicable to other large protein domains in the plasma membrane. © 2012 Wiley Periodicals, Inc
Anatomical basis of sun compass navigation I: The general layout of the monarch butterfly brain
Authors: Heinze Stanley , Reppert Steven M.
Published: April 2012

The eastern North American monarch butterfly (Danaus plexippus) is well known for its long‐distance fall migration. To illuminate the neural basis of sun compass navigation during the migration, the layout of the monarch butterfly brain was analyzed by immunocytochemistry and three‐dimensional reconstructions. The monarch brain is depicted in anti‐synapsin‐labeled serial sections (grayscale images), as well as a three‐dimensional reconstruction (color image). The Journal of Comparative Neurology, Volume 520, Number 8, pages 1599–1628.
Development of tyrosine hydroxylase‐immunoreactive cell populations and fiber pathways in the brain of the dogfish Scyliorhinus canicula: New perspectives on the evolution of the vertebrate catecholaminergic system
Authors: Carrera Iván , Anadón Ramón , Rodríguez‐Moldes Isabel
Published: April 2012

Developmental studies of the central catecholaminergic (CA) system are essential for understanding its evolution. To obtain knowledge about the CA system in chondrichthyans, an ancient gnathostome group, we used immunohistochemical techniques for detecting tyrosine hydroxylase (TH), the initial rate‐limiting enzyme of the CA synthesis, to study: 1) the neuromery of developing TH‐immunoreactive (ir) neuronal populations, 2) the development of TH‐ir innervation, and 3) the organization of TH‐ir cells and fibers in the brain of postembryonic stages of the shark Scyliorhinus canicula. The first TH‐ir cells appeared in the hypothalamus and rostral diencephalon (suprachiasmatic, posterior recess and posterior tubercle nuclei at embryonic stage 26, and dorsomedial hypothalamus at stage 28); then in more caudal basal regions of the diencephalon and rostral mesencephalon (substantia nigra/ventral tegmental area); and later on in the anterior (locus coeruleus/nucleus subcoeruleus) and posterior (vagal lobe and reticular formation) rhombencephalon. The appearance of TH‐ir cells in the telencephalon (pallium) was rather late (stage [S]31) with respect to the other TH‐ir prosencephalic populations. The first TH‐ir fibers arose from cells of the posterior tubercle (S30) and formed recognizable ascending (toward dorsal and rostral territories) and descending pathways at S31. When the second half of embryonic development started (S32), TH‐ir fibers innervated most brain areas, and nearly all TH‐ir cell groups of the postembryonic brain were already established. This study provides key information about the evolution of the developmental patterns of central CA systems in fishes and thus may help in understanding how the vertebrate CA systems have evolved. J. Comp. Neurol. 520:3574–3603, 2012. © 2012 Wiley Periodicals, Inc.
Phox2b expression in the taste centers of fish
Authors: Coppola Eva , D'autréaux Fabien , Nomaksteinsky Marc , Brunet Jean‐François
Published: April 2012

The homeodomain transcription factor Phox2b controls the formation of the sensory‐motor reflex circuits of the viscera in vertebrates. Among Phox2b‐dependent structures characterized in rodents is the nucleus of the solitary tract, the first relay for visceral sensory input, including taste. Here we show that Phox2b is expressed throughout the primary taste centers of two cyprinid fish, Danio rerio and Carassius auratus, i.e., in their vagal, glossopharyngeal, and facial lobes, providing the first molecular evidence for their homology with the nucleus of the solitary tract of mammals and suggesting that a single ancestral Phox2b‐positive neuronal type evolved to give rise to both fish and mammalian structures. In zebrafish larvae, the distribution of Phox2b+ neurons, combined with the expression pattern of Olig4 (a homologue of Olig3, determinant of the nucleus of the solitary tract in mice), reveals that the superficial position and sheet‐like architecture of the viscerosensory column in cyprinid fish, ideally suited for the somatotopic representation of oropharyngeal and bodily surfaces, arise by radial migration from a dorsal progenitor domain, in contrast to the tangential migration observed in amniotes. J. Comp. Neurol. 520:3633–3649, 2012. © 2012 Wiley Periodicals, Inc.
Anatomical plasticity in the adult zebra finch song system
Authors: McDonald Kathryn S. , Kirn John R.
Published: April 2012

In many songbirds, vocal learning‐related cellular plasticity was thought to end following a developmental critical period. However, mounting evidence in one such species, the zebra finch, suggests that forms of plasticity common during song learning continue well into adulthood, including a reliance on auditory feedback for song maintenance. This reliance wanes with increasing age, in tandem with age‐related increases in fine motor control. We investigated age‐related morphological changes in the adult zebra finch song system by focusing on two cortical projection neuron types that 1) share a common efferent target, 2) are known to exhibit morphological and functional change during song learning, and 3) exert opposing influences on song acoustic structure. Neurons in HVC and the lateral magnocellular nucleus of the anterior nidopallium (LMAN) both project to the robust nucleus of the arcopallium (RA). During juvenile song learning and adult song maintenance, HVC promotes song syllable stereotypy, whereas LMAN promotes learning and acoustic variability. After retrograde labeling of these two cell types in adults, there were age‐related increases in dendritic arbor in HVC‐RA but not LMAN‐RA neurons, resulting in an increase in the ratio of HVC‐RA:LMAN‐RA dendritic arbor. Differential growth of HVC relative to LMAN dendrites may relate to increases in song motor refinement, decreases in the reliance of song on auditory feedback, or both. Despite this differential growth with age, both cell types retain the capacity for experience‐dependent growth, as we show here. These results may provide insights into mechanisms that promote and constrain adult vocal plasticity. J. Comp. Neurol. 520:3673–3686, 2012. © 2012 Wiley Periodicals, Inc.
A note about the abnormal hue angle change in CIELAB space
Authors: Li Changjun , Melgosa Manuel
Published: April 2012

Liu et al. [Color Res Appl 1995;20:245–250] compared the CIELAB hue angles under CIE illuminants D65 and A for quantifying the color appearance changes for gem materials. They found that CIELAB hue angle for some gem materials under illuminant D65 was larger than under A, which is contrary to the perceived blue and purple appearances under daylight and incandescent light sources, respectively. They called this phenomenon as the abnormal hue angle change in the CIELAB space for the gem materials. In this article, we note the proper way to quantify the appearance changes is to use chromatic adaptation transforms (CATs), since we are only concerning the color change of the illumination. At the same time, it is found that the chromatic adaptations in the sharper sensor space and in the cone fundamental space provide different results, the ones related to the latter being in better agreement with current blue‐to‐purple color appearance change. © 2012 Wiley Periodicals, Inc. Col Res Appl, 38, 322–327, 2013
A trust management model for service‐oriented distributed networks
Authors: Yu Yanli , Li Keqiu , Jin Yingwei , Zhang Yong
Published: April 2012

The service‐oriented distributed network requires more stable and persistent services, but the services from dishonest or unstable nodes would damage the correctness and availability of services. To efficiently obtain the services from high dependable nodes, many trust management systems have been developed. However, the previous trust models in distributed networks ignore a fact that the entity itself could provide trust information for services also. In this paper, we present a novel trust management model based on the subjective logic trust for service‐oriented distributed networks. The proposed algorithm involves passive trust of entity and combines the direct trust and recommendation trust. We also propose a novel scheme called passive trust feedback to avoid the deceit of malicious nodes and unstable nodes, and to encourage honest nodes. Our proposed model expands the trust range of service resource via passive trust of entity, which generates a flexible access path to the service resources. Simulations show that the proposed trust management model can significantly improve the feasibility of trust management as well as effectively detect malicious entities. Copyright © 2012 John Wiley & Sons, Ltd.