bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mathematical structures in pattern organizations
Authors: Kodituwakku Saluka R 
Published: January 2011

Since the introduction of design patterns, a large number of patterns have been identified and documented. As a result, patterns in the literature relate one another in different ways. Unfortunately, most of these patterns are not properly organized. In applying these patterns in to problems at hand novice designers encounter many difficulties such as identification and selection of collectively applicable set of patterns that suits the problem at hand. We investigate mathematical structures in existing pattern organization techniques such as pattern catalogues, pattern systems and pattern languages. Then we attempted to use these mathematical structures in developing a new organization technique. This paper proposes a new organization method and illustrates it with a collection of object oriented patterns drawn from the literature. Our investigation indicated that existing pattern organizations form graph structures and categorical structures. These structures are formed by patterns and relationships among them. The proposed organization method organizes patterns into sequences according to the relationships among patterns. This organization consists of two types of categories: major category and alternative category. The major categories are defined based on the Uses relationship and the alternative categories are defined based on the Variants, Refines and Conflicts relationships. Each major category consists of patterns that have potential to form a pattern system or a pattern language. So they assist practitioners in finding a sequence of related patterns that can be collectively applied to solve complex problems. Each alternative category consists of patterns that provide alternative solutions to the same problem or similar problems. It assists in finding a number of possible solutions (patterns) to a particular problem. The proposed organization combines these two types of categories by structuring them into pattern sequences. A pattern sequence consists of a major category and a collection of related alternative categories. Pattern sequences assist practitioners in finding a collectively applicable patterns and possible alternatives to them. So pattern sequences facilitate the selection of most appropriate sequences of patterns to solve complex problems without searching through the pattern literature. Key Words: Design Patterns; Pattern Catalogues; Pattern Systems; Pattern Languages; Pattern Sequences; Category Theory; GraphsDOI: 10.4038/josuk.v4i0.2697J Sci.Univ.Kelaniya 4 (2008): 46-67
One-Parameter Continuous Fields of Kirchberg Algebras. II
Authors: Dadarlat Marius , Elliott George A. , Niu Zhuang 
Published: January 2011

Abstract Parallel to the first two authors’ earlier classification of separable, unital, one-parameter, continuous fields of Kirchberg algebras with torsion free K-groups supported in one dimension, one-parameter, separable, unital, continuous fields of AF-algebras are classified by their ordered K0-sheaves. Effros-Handelman-Shen type theorems are proved for separable unital one-parameter continuous fields of AF-algebras and Kirchberg algebras.
A Variant of Lehmer’s Conjecture, II: The CM-case
Authors: Gun Sanoli , Kumar Murty V. 
Published: January 2011

Abstract Let f be a normalized Hecke eigenform with rational integer Fourier coefficients. It is an interesting question to know how often an integer n has a factor common with the n-th Fourier coefficient of f. It has been shown in previous papers that this happens very often. In this paper, we give an asymptotic formula for the number of integers n for which (n, a(n)) = 1, where a(n) is the n-th Fourier coefficient of a normalized Hecke eigenform f of weight 2 with rational integer Fourier coefficients and having complex multiplication.
Structural Proteins: Genes for Collagen
Authors: Chu Mon‐Li 
Published: January 2011

Abstract

Structural proteins are required for the formation and support of body tissues. Collagens, characterised by the repeating Gly–X–Y amino acid sequences, are the most abundant structural proteins in the human body. The collagen gene family comprises 45 genes encoding 28 homo‐ or heterotrimeric collagen types. With some exceptions, most collagen genes are scattered on different chromosomes. All except two of the collagen genes are highly interrupted, with exon numbers up to 118. This is primarily because exons coding for the collagenous domains are relatively small and usually encode a discrete number of Gly–X–Y repeated sequences, and as such the lengths are multiples of 9 base pairs (bp). In the fibrillar collagen genes, exons encoding the Gly–X–Y sequences are most frequently 54 bp or a variation thereof, and start with complete codons for glycine. In the nonfibrillar collagen genes, the most frequent exon sizes are 27, 36 or 63 bp.

Key Concepts:

Collagens are the most abundant structural proteins in the human body, accounting for approximately 25% of the total protein mass.

Collagens are homo‐ or heterotrimers, in which three collagen polypeptides, called α chains, align in parallel and fold into a unique triple‐helical structure, which is based on the repeating Gly–X–Y amino acid sequence of the α chains.

The collagens are generally divided into two major classes: fibrillar collagens that form characteristic cross‐striated fibrils and nonfibrillar collagens that do not form cross‐striated fibers.

To date, 28 vertebrate collagen types, I–XXVIII, encoded by 45 distinct genes, have been described in the literature.

With some exceptions, most collagen genes are scattered on different human chromosomes.

Collagen genes are large and highly interrupted, except for the genes for types VIII and X collagen.

In fibrillar collagen genes, exons coding for the Gly–X–Y sequences are most frequently 54 bp or a variation thereof, and start with complete codons for glycine.

The nonfibrillar collagen genes do not show the 54‐bp exon size pattern. The most frequent exon sizes are 27, 36 or 63 bp, and some exons start with a split codon for glycine.
DNA
Strand Break Repair and Human Genetic Disease
Authors: García‐Muse Tatiana , Aguilera Andrés 
Published: January 2011

Abstract

Deoxyribonucleic acid
(DNA) is constantly exposed to exogenous and endogenous DNA damaging agents. Among the different types of DNA damage that arise in the cells, single‐strand breaks (SSBs) and double‐strand breaks (DSBs) are a serious threat to genetic integrity and cell survival. To minimise the impact of these lesions, cells have evolved various DNA repair mechanisms depending on the kind of DNA damage. The importance of DNA strand break repair is highlighted by the observation that many proteins involved in the repair pathways are mutated in a wide variety of cancers and in different types of hereditary diseases. These disorders display a variety of features. Notably, syndromes related with defects in the repair of single‐strand breaks exhibit a pathology that is restricted to cerebellar ataxia and neurodegeneration, whereas DSB repair syndromes exhibit a more diverse pathology and can include developmental abnormalities, microcephaly and cancer predisposition.

Key Concepts:

The DNA damage response (DDR) is a signal transduction pathway that starts with the sensing of the damage and coordinates cell cycle, repair and apoptosis.

DDR plays an important role in development and preservation of genome stability and, consequently, is crucial for cancer prevention and normal ageing.

Many proteins involved in DNA repair pathways are mutated in a wide variety of cancers and in different types of hereditary diseases.

Homologous recombination is a DNA repair pathway linked to replication and devoted to the repair of DNA breaks using an intact DNA template to copy information.

Nonhomologous end‐joining (NHEJ) is a double‐strand break repair pathway that ligates the two ends without using any DNA template.

DSB repair syndromes exhibit a diverse pathology and can include developmental abnormalities, microcephaly and cancer predisposition.

Syndromes with impaired NHEJ also show dramatic immunological defects highlighting the role of NHEJ during development of the immunological system.

Syndromes related with defects in the repair of single‐strand breaks exhibit a pathology that is restricted to cerebellar ataxia and neurodegeneration.
Sexual Selection and Experimental Evolution
Authors: Garcia‐Gonzalez Francisco 
Published: January 2011

Abstract

Sexual selection is a potent force shaping multiple aspects of the interaction between the sexes, including the characters underlying reproductive success and sexual conflict, and may play an important role in determining the viability of populations. Experimental evolution is a methodological approach in which researchers either act as selective agents or establish the selective pressures operating on individuals to investigate changes in traits across generations and the genetic underpinning of these changes. Experimental evolution replicates the evolutionary process under controlled conditions and, by doing so, offers exceptional insights into the role of variation, selection and adaptation in evolution. Applied to the study of pre‐copulatory (before mating) and post‐copulatory (after mating) sexual selection, experimental evolution proves critical to understand the evolutionary consequences of male–male competition and female mate choice, and the repercussions of concurrent or divergent interests between the sexes in regard to reproduction.

Key Concepts:

Experimental evolution is a methodological approach to study adaptation under controlled experimental conditions.

Sexual selection shapes the characters underlying reproductive success.

Experimental evolution is a powerful tool for understanding the evolutionary consequences of sexual selection and sexual conflict.
Escherichia coli
Cotranslational Targeting and Translocation
Authors: von Loeffelholz Ottilie , Botte Matthieu , Schaffitzel Christiane 
Published: January 2011

Abstract

Targeting of proteins to their proper location inside the cell, in the membrane or in the extracellular space is crucial to the cell. The targeting information is provided in form of a signal sequence by the protein itself. In

Escherichia coli

, mostly membrane proteins are targeted cotranslationally via the signal recognition particle (SRP) to the membrane. The SRP and its receptor are both
guanosine triphosphatases
(GTPases) which handover the ribosome‐nascent chain complex to the protein‐conducting channel. Subsequently, the nascent polypeptide is translocated into or across the membrane. To date, a host of biochemical data and a number of structures of important complexes along the pathway are available which shed light on the molecular mechanism of the targeting and translocation process.

Key Concepts:

Nascent polypeptides with signal sequences are recognised by the SRP.

The hydrophobicity of the signal sequence determines whether a protein is targeted co‐ or posttranslationally.

Cotranslational protein targeting is mediated by the SRP and the SRP receptor. They deliver the translating ribosome to the translocation machinery in the membrane.

The SecYEG translocon is a channel that allows hydrophilic polypeptides to cross the membrane. In addition, the channel can open laterally and release transmembrane helices into the lipid bilayer.

YidC acts as a membrane protein insertase for small membrane proteins in a Sec‐independent manner. In a Sec‐associated form, YidC is suggested to assist in membrane protein folding.

YidC, SecD, SecF and YajC can associate with the SecYEG protein‐conducting channel. The resulting complex is called the ‘holotranslocon’, which is suggested to be responsible for membrane protein integration, folding and complex assembly.
Gas‐Phase Chemistry of Organocopper Compounds
Authors: Lamsabhi Al Mokhtar , Yáñez Manuel , Salpin Jean‐Yves , Tortajada Jeanine 
Published: January 2011

Abstract

Introduction

Performance of Different Theoretical Models

Ligand‐Field Spectroscopy and Photofragmentation Processes

Cu
+
and
Cu
2+
Binding Energies

Coordination

Bonding

Cu
+
/
Cu
2+
Reactions with Small Organic Bases

Gas‐Phase Reactivity of Copper(
I
) and Copper(
II
) Ions toward Molecules of Biological Relevance
The Effect of the Connectivity of Rigid Phases on Strength of AlSi Alloys
Authors: Requena Guillermo , Garcés Gerardo , Asghar Zahid , Marks Esteban , Staron Peter , Cloetens Peter 
Published: January 2011

AbstractThe load carrying capacity of the eutectic Si in AlSi alloys depends on its volume fraction, distribution, morphology and connectivity, namely its internal architecture. This can be modified by heat treatment at temperatures close to the eutectic point causing the spheroidisation and loss of connectivity of the eutectic Si. This decreases the load carrying capacity of the eutectic Si and, consequently, the room and high temperature strength of AlSi alloys is reduced. The presence of other phases such as ceramic short fibres and aluminides in AlSi alloys can result in the formation of hybrid three‐dimensional structures that strongly delay and/or suppress the morphological changes and the loss of connectivity of the eutectic Si. As a result, the thermo‐mechanical behaviour of these heterogeneous lightweight materials is improved and stable. These effects have been explored in the last years by the authors and the main results are compiled and presented in the present work with special emphasis in the relationship between the architecture and the strength of different AlSi‐based materials.
Enhanced Homogenization Strategy by Electroslag Remelting of High‐Manganese TRIP and TWIP Steels
Authors: Reitz Jan , Wietbrock Burkhard , Richter Silvia , Hoffmann Sascha , Hirt Gerhard , Friedrich Bernd 
Published: January 2011

AbstractIn the production of high‐manganese TRIP and TWIP steels, significant micro‐segregation effects are observed after solidification. Homogenization can be achieved by heat treatment followed by deformation at a significant time and effort (forging, annealing, hot rolling). In an attempt to achieve the best homogeneous microstructure and reduced thermomechanical processing, the cast alloy is treated by electroslag remelting (ESR). After a simple hot rolling procedure with a thickness reduction of 90% and without further heat treatment, micro‐segregation of manganese can be reduced to about 5 wt%. There is a potential to achieve even lower values with further optimization of the ESR process and an adapted thermomechanical processing.
Structure–Process–Property Relationship of Biomimetic Chitosan‐Based Nanocomposite Scaffolds for Tissue Engineering: Biological, Physico‐Chemical, and Mechanical Functions
Authors: Maganti Nagini , Venkat Surya Pavan K. C. , Thein‐Han Wah Wah , Pesacreta Thomas C. , Misra R. Devesh K. 
Published: January 2011

AbstractWe describe here the structure–property–process relationship of two sets of chitosan‐based scaffolds as potential materials for hard tissue bioengineering applications. The first set of scaffolds was designed to study the effect of degree of deacetylation (%DD) of chitosan at 85 and 95% DD with identical molecular weight. The second set of scaffolds were synthesized to enhance the bioactivity and mechanical properties of 95% DD chitosan scaffold by the addition of 1, 3, and 5 wt% nanohydroxyapatite (nHA). Both sets of scaffolds were processed using freezing and lyophilization and their in vitro biological response was examined using pre‐osteoblast (MC 3T3‐E1) cells. The pure chitosan and chitosan–nHA nanocomposite scaffolds were characterized by a three‐dimensional porous structure with pore size in the range of (≈50–120 µm), irrespective of %DD and nHA content. The compression modulus of hydrated 95% DD chitosan scaffolds increased from 6.0 kPa in pure chitosan to 9.2 kPa in chitosan‐5 wt% nHA. The water uptake ability of 95% DD chitosan scaffolds was lower than 85% DD chitosan scaffolds, and decreased with the addition of nHA. On the other hand the water retention ability of 95% DD chitosan scaffolds was greater than 85% DD chitosan scaffolds but did not increase much with the addition of nHA. Chitosan degrades mainly by lysozyme present in physiological fluid. After 28 days of in vitro biodegradation test with physiological fluid, the 95% DD chitosan exhibited slightly lower degradation rate as compared to 85% DD and the degradation decreased with increase in nHA content in chitosan scaffold. Pre‐osteoblasts (MC3T3‐E1) grown on nHA scaffolds showed improved cell attachment, more proliferation, and a more extended cellular morphology. In vitro experimental observations suggest chitosan–nHA nanocomposite scaffolds as potential biomaterials for hard tissue bioengineering (bone regeneration) or as a template for cell attachment and proliferation in the repair of osseous and chondral defects.
Single‐step attribution of increasing frequencies of very warm regional temperatures to human influence
Authors: Stott Peter A. , Jones Gareth S. , Christidis Nikolaos , Zwiers Francis W. , Hegerl Gabriele , Shiogama Hideo 
Published: January 2011

AbstractSeasonal near‐surface temperatures have increased in many regions of the World. Previous work has shown that this has led to rapidly increasing frequencies of very warm Northern Hemisphere summer temperatures. Here we show, using a ‘single‐step’ attribution framework, that increases in frequencies of very warm seasonal temperatures, not just in Northern Hemisphere summers but in other regions and seasons, can be directly attributed to human influence. In the June‐August and September‐November seasons, many of the sub‐continental regions of Africa and Asia show robust attributable increase in the frequencies of anomalously warm seasonal temperatures. Copyright © 2011 Royal Meteorological Society, Crown Copyright and Crown in the right of Canada
A Versatile Tripodal Host with Cylindrical Conformation: Solvatomorphism, Inclusion Behavior, and Separation of Guests
Authors: Wei Wei , Wang Guo , Zhang Ying , Jiang Feilong , Wu Mingyan , Hong Maochun 
Published: January 2011

AbstractTripodal host 2,4,6‐tris(1‐phenyl‐1H‐tetrazolylsulfanylmethyl)mesitylene (TPTM) has been synthesized through a facile procedure. As expected, it adopts an all‐syn cylindrical configuration, thereby delimiting an inner cavity. To explore the solvatomorphism and inclusion behavior of TPTM, a series of organic and inorganic species were employed as guests to afford 17 inclusion compounds (1, 2, 3 a–3 f, 4 a–4 i) that can be classified into four distinct forms (forms I–IV), under similar conditions. These compounds were characterized by single‐crystal and powder X‐ray diffraction, and 1H NMR studies. In compound 1 with form I, one foot of a TPTM molecule inserts into the cavity of an opposite TPTM molecule to form a dimeric “hand‐shake” motif with one acetonitrile molecule occupying the void. Compound 2 with form II contains three types of capsule‐shaped dimers, each of which holds a CH2Cl2 molecule as the guest. In compounds 3 a–3 f with form III, each pair of TPTM molecules interdigitates to form a capsule‐shaped dimeric unit accommodating a guest molecule in the endo‐cavity. In compounds 4 a–4 i with form IV, each TPTM molecule makes contact with three nearby TPTM molecules in a “self‐including” manner to generate a graphite‐like organic layer, and through further superposition to form open hexagonal channels. From the experimental and theoretical results, the intrinsic properties of guest molecules, such as size, shape, and self‐interaction, can be regarded as the main factors leading to these solvatomorphism phenomena and the subtle inclusion behavior of TPTM. Thermogravimetric analyses show that the encapsulated guest molecules in these compounds can be evacuated at relatively high temperatures, and this demonstrates the outstanding inclusion capability of TPTM. In addition, for compound 4 a with benzene molecules in the channels, reversible exchange of toluene and separation of xylene isomers on single crystals have been observed.
Synthesis and Structure Analysis of (K[DB18 C6])4(C60)5⋅12 THF Containing C60 in Three Different Bonding States
Authors: Kozhemyakina Nina V. , Amsharov Konstantin Yu. , Nuss Jürgen , Jansen Martin 
Published: January 2011

AbstractA new fulleride, (K[DB18C6])4(C60)5⋅12 THF, was prepared in solution using the “break‐and‐seal” approach by reacting potassium, fullerene, and dibenzo[18]crown‐6 in tetrahydrofuran. Single crystals were grown from solution by the modified “temperature difference method”. X‐ray analysis was performed revealing a reversible phase transition occurring on cooling. Three different crystal structures of the title compound at different temperatures of data acquisition are addressed in detail: the “high‐temperature phase” at 225 K (C2, Z=2, a=49.055(1), b=15.075(3), c=18.312(4) Å, β=97.89(3)°), the “transitional phase” at 175 K (C2 m, Z=2, a=48.436(5), b=15.128(1), c=18.280(2) Å, β=97.90(1)°), and the “low‐temperature phase” at 125 K (Cc, Z=4, a=56.239(1), b=15.112(3), c=36.425(7) Å, β=121.99(1)°). On cooling, partial radical recombination of C60.− into the (C60)22− dimeric dianion occurs; this is first time that the fully ordered dimer has been observed. Further cooling leads to formation of a superstructure with doubled cell volume in a different space group. Below 125 K, C60 exists in the structure in three different bonding states: in the form of C60.− radical ions, (C60)22− dianions, and neutral C60, this being without precedent in the fullerene chemistry, as well. Experimental observations of one conformation exclusively of the fullerene dimer in the crystal structure are further explained on the basis of DFT calculations considering charge distribution patterns. Temperature‐dependent measurements of magnetic susceptibility at different magnetic fields confirm the phase transition occurring at about 220 K as observed crystallographically, and enable for unambiguous charge assignment to the different C60 species in the title fulleride.
Removal of Natural Free Estrogens and their Conjugates in a Municipal Wastewater Treatment Plant
Authors: Liu Ze‐hua , Kanjo Yoshinori , Mizutani Satoshi 
Published: January 2011

AbstractRemoval of natural free estrogens and estrogen conjugates in a municipal wastewater treatment plant (WWTP) was investigated and analyzed by GC‐MS, in which estrogen conjugates were first transformed to their corresponding free estrogens with an acid solvolysis procedure before their analysis. Natural free estrogens, E1‐3‐sulfate (E1‐3S), and E3‐3‐sulfate (E3‐3S) were detected with high concentrations in both the influent and effluent of the primary settling tank (PS), while no estrogen glucuronides were detected in any of the monitored wastewater samples. Regarding their removal efficiencies, all were almost completely removed, except for E1 with only a minor decrease. The estrogenic/androgenic removal of the same WWTP was also evaluated with estrogen receptor (androgen receptor) (ER (AR))‐binding assays, in which the removal efficiencies for E2 equivalents (EEQ) or testosterone equivalents (TEQ) were 68.5 and 72.2%. In addition, the chemically calculated EEQ from natural estrogens were about 20.6–39.3% that of the ER‐binding assay, in which E3 contributed the biggest proportion in both the influent and PS, while the calculated value of E1 increased from only 6.7% in the influent to as high as 20.6% in the effluent.