bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular Genetics of Metabolic Syndrome
Authors: Chang Yi‐Cheng , Yu Yu‐Hsiang , Chuang Lee‐Ming
Published: April 2013

The clustering of metabolic traits (known as metabolic syndrome), including central obesity, abnormal glucose regulation, dyslipidemia and elevated blood pressure, was associated with increased risk of cardiovascular disease and type 2 diabetes. The close clustering and strong heritability of these metabolic traits suggest a common underlying genetic basis. Genetically modified mice models and identification of causative gene for human monogenic obesity/insulin resistance syndrome provided important insights into the pathogenesis of the metabolic syndrome. Recent genome‐wide association studies (GWAS) also identified several genes reproducibly associated with the metabolic syndrome or multiple metabolic traits, including genes involved in lipid metabolism (
CETP, APOA1/C3/A4/A5
cluster,
LPL
,
LIPC
and
ABCB11
), glucose sensing (
GCKR
), insulin signalling (
IRS1
), beta‐cell function (TCF7L2) and appetite control (
FTO
). However, these variants explain only a small fraction of the observed heritability. Further pursuit for structural variants, rare sequence variants and epigenetic modification related to the metabolic syndrome may help to elucidate the unexplained heritability.

Key Concepts:

The estimated heritability of the metabolic syndrome and related metabolic traits (including obesity, dyslipidemia, abnormal glucose regulation and elevated blood pressure) is relatively high.

Genetically modified knockout mice models and human monogenic obese/insulin resistant syndrome provide important molecular insights into the pathogenesis of the metabolic syndrome.

Family linkage mapping for the metabolic syndrome is of limited success because of inconsistency among studies.

Large‐scale genome‐wide association mapping identified many genetic loci associated with the metabolic syndrome and related traits. Important loci are located in genes involved in lipid metabolism (
CETP, APOA1/C3/A4/A5
cluster,
LPL
,
LIPC
and
ABCB11
), glucose sensing (
GCKR
), insulin signalling (
IRS1
), beta‐cell function (TCF7L2) and appetite control (
FTO
).

The genetic variants identified by genome‐wide association mapping explain only a minor fraction of the estimated heritability. Other potential contributors to the unexplained heritability are structural variants, rare sequence variants and epigenetic modification.
Molecular Genetics of Fanconi Anaemia
Authors: Green Allison M , Kupfer Gary M
Published: April 2013

Cells derived from Fanconi anaemia (FA) patients display hypersensitivity to
deoxyribonucleic acid
(DNA) cross‐linking agents such as MMC and DEB. Treatment with these agents induces an abnormally prolonged cell cycle arrest in S phase and an accumulation of cells with 4N DNA. Based on this response, the FA pathway has been hypothesised to function in sensing DNA damage induced by these agents and in initiating its repair. This hypothesis has been supported by work elucidating the interactions of FA proteins with proteins known to be involved in DNA‐damage sensing, signalling and repair. Additionally, a significant body of work has pointed to a role of the FA pathway in the cellular response to oxidative stress. Although the exact mechanisms and functions of the FA pathway are yet to be discovered, the interaction of the members of the FA pathway with proteins associated with DNA repair, cellular signalling and oxidative stress management leads to the hypothesis that the FA pathway proteins serve many varied functions throughout the cell.

Key Concepts:

The FA pathway overlaps significantly with other DNA repair pathways such as homologous recombination, translesion synthesis and mismatch repair.

FA pathway proteins are involved in the intricate cellular signalling that occurs following DNA damage.

FA pathway proteins are involved in regulating oxidative stress.

FA mutant cells display hypersensitivity to DNA damage, particularly DNA crosslink's.

FA patients are particularly prone to malignancy, especially myeloid leukemia and squamous cell carcinomas of the head and neck and genitourinary track.
Molecular Genetics of Incontinentia Pigmenti
Authors: Ursini Matilde Valeria , Conte Matilde Immacolata , Pescatore Alessandra , Miano Maria Giuseppina , Fusco Francesca
Published: April 2013

Incontinentia Pigmenti (IP) is a rare X‐linked dominant neuroectodermal disorder caused by mutations in the nuclear factor kappaB essential modulator (
NEMO
)/Inhibitor of Kappa light polypeptide gene enhancer in B‐cells Kinase Gamma (
IKBKG
) gene. The
NEMO locus
maps in a region with a unique genomic organisation: in the centromeric direction,
NEMO
partially overlaps the
glucose‐6‐phosphate dehydrogenase
gene; in the telomeric direction,
NEMO
is part of a 35.7 kb segmental duplication containing its nonfunctional truncated copy
pseudoNEMO
. Moreover, a high frequency of micro‐/macro‐homologies, tandem repeats and repeat/repetitive sequences characterise the local architecture of the
locus
increasing its vulnerability to the production of

de novo

genomic rearrangements through different mechanisms. Indeed, instances of nonallelic homologous recombination (NAHR) causing both benign and pathological alleles, nonhomologous end joining (NHEJ) and
Alu
–
Alu
‐mediated recombination events producing either recurrent or nonrecurrent deletions have been reported. These events, occurring during both meiosis and mitosis, reveal that the region is prone to generate complex human genomic rearrangements.

Key Concepts:

Genomic rearrangements in the
NEMO
gene can be generated during meiosis or mitosis.

Low copy repeats or segmental duplication regions can act as substrates for aberrant recombination and for gene conversion events.

The complex architecture of the
locus
enhances its vulnerability to the production of
de novo
genomic rearrangements through different mechanisms.

The mutational mechanisms that can give rise to genomic rearrangements in the IP
locus
are: NAHR, NHEJ,
Alu–Alu
mediated recombination and gene conversion.

NAHR, mediated through sequences that exhibit a considerable homology called
MER67B
, is one of the major mechanisms for the generation of
de novo
rearrangements in the IP
locus
.
Application of Chromosome Conformation Capture (3C) to the Study of Human Genetic Disease
Authors: Horan Martin P , Ballard J William O
Published: April 2013

Chromosome conformation capture (3C) is a powerful technique that allows for the generation of 3‐dimensional transcriptome organisational maps. 3C facilitates the identification and quantitative measurement of distant chromosomal regulatory elements with proximal gene promoter regions. This is achieved by fixing protein onto
deoxyribonucleic acid
(DNA) followed by restriction enzyme digestion or sonication to shear the DNA prior to re‐ligation of the fixed DNA region. PCR amplification of a chromosomal region of interest can then be performed and quantified. Next generation sequencing platforms on prepared 3C chromatin can provide information on whole genome regulatory networks. The technology and its modified derivatives provide high levels of resolution and throughput for determining nuclear organisation and allows for the identification of novel noncoding DNA regions that are associated with controlling gene expression. 3C is providing important insights into underlying mechanisms that may be responsible for various human diseases including cancer, muscular dystrophies, neurological and metabolic disorders.

Key Concepts:

Chromosome conformation capture (3C) is a key strategy used to determine distant chromosomal regulatory regions involved with controlling gene expression.

Single nucleotide polymorphic (SNP) DNA variations in noncoding region DNA can now be interrogated to determine a functional role in altering gene expression.

The 3‐dimensional chromosome looping architecture can be dissected to determine multiple chromosomal regions involved with regulating gene expression through transcription factory interaction.

Mutations in distant chromosomal regulatory regions may lead to uncontrolled repression of oncogenes allowing for increases in tumour growth and development.

Identifying noncoding chromosomal regions associated with nuclear adaptive mechanisms in response to DNA mutation may allow us to determine critical regions involved with maintaining cellular homoeostasis.

High‐throughput sequencing strategies are allowing for unparalleled identification of DNA variation in the human genome.
GLI
Proteins in Human Genetic Disease
Authors: Olena Zhulyn , Chi‐chung Hui
Published: April 2013

GLI1, GLI2 and GLI3 transcription factors are the key effectors of mammalian Hedgehog signalling. Mutations in these transcription factors are implicated in severe congenital malformations and malignancies in humans and in mice. Analysis of mouse models has revealed that the patterning and development of multiple organ systems is dependent on a tightly regulated balance of Gli activator and repressor activity. Consequently, mutations in the Hh pathway machinery that affect Gli function or processing result in phenotypes with a striking resemblance to GLI‐associated disorders. The primary cilium was identified as a critical component of Hh signalling due to the phenotypic overlap between Hh‐pathway mutants and mice with defects in ciliogenesis. Many mutations in genes regulating cilia structure and function have been identified in human ciliopathies. This new class of diseases shares significant phenotypic overlap with GLI‐related syndromes. Phenotypic analysis of mice with compromised cilia function has revealed new aspects of Gli regulation demonstrating the utility of mouse models in the characterisation of novel disease phenotypes.

Key Concepts:

Balance of GLI activator and repressor is required for normal development.

Shift of the balance towards low or high GLI3R levels results in severe congenital malformations.

Shift of the balance towards high GLI activator results in cancer.

Mutations affecting different domains of bifunctional transcription factor Gli3 give rise to distinct phenotypes.

Mutations affecting Hh pathway machinery affect Gli processing and activity and result in Gli‐related phenotypes.

The primary cilium is critical for Hh signal transduction.

Mutations in regulators of primary cilia structure and function result in ciliopathies, which share many overlapping phenotypes with GLI‐associated syndromes.
Molecular Genetics of Cystinuria
Authors: Eggermann Thomas
Published: April 2013

Among the kidney stone diseases, cystinuria (OMIM
220100
) is unique as it is exclusively caused by genomic alterations. Cystinuria is associated with mutations in the
SLC3A1
and the
SLC7A9
genes encoding the subunits rBAT and b
0,+
AT of the renal b
0,+
transporter. Mutations in
SLC3A1
are usually inherited autosomal recessively, but
SLC7A9
mutations result in a broad clinical variability. The detection rate for mutations is influenced by the ethnic origin of the patient and by the functional significance of the variant. As a result, mutations cannot be detected in 100% of alleles, but it reaches approximately 85%. In case of
SLC3A1
, large rearrangements in 2p21 cause cystinuria and severe hypotonia (hypotonia–cystinuria syndrome – HCS). Meanwhile, a large number of mutations in both genes have been reported, several of these variants were functionally analysed. Thereby, the aetiology of the disease as well as the physiological mechanisms of the renal trafficking of cystine could be deciphered.

Key Concepts:

Cystinuria is characterised by the defect transport of cystine, resulting in cystine stone formation.

With
SLC3A1
and
SLC7A9,
two disease causing genes have been identified.

SLC3A1
and
SLC7A9
encode the two subunits of the amino acid transporter b
0,+
.

Mutations in
SLC3A1
are predominantly associated with an autosomal recessive inheritance, whereas
SLC7A9
mutations show an autosomal dominant inheritance with an incomplete penetrance.

Homozygosity for large genomic deletions affecting both the
SLC3A1
and the
PREPL
gene in 2p21 cause the hypotonia–cystinuria syndrome.
Li
NC
Complex and Human Genetic Muscular Disease
Authors: Wehnert Manfred S , Meinke Peter
Published: April 2013

The linker of nucleoskeleton and cytoskeleton (LiNC) complex is a proposed mechanical link tethering the nucleo‐ and cytoskeleton via the nuclear envelope (NE). The LiNC components emerin, lamin A/C, SUN1, SUN2, nesprin 1 and nesprin 2 interact with each other at the NE and also with other binding partners including actin filaments and B‐type lamins. Besides the mechanostructural functions, cell‐ or tissue‐specific LiNC complexes are also involved in signalling pathways and gene regulation. Emerin was the first LiNC component associated with a human disease, namely Emery–Dreifuss muscular dystrophy (EDMD). Later on, other components of a hypothetically muscle‐specific LiNC complex, such as lamins A/C and small muscle‐specific isoforms of nesprin 1 and nesprin 2, were found to be associated with EDMD, reflecting a genetic heterogeneity that has not been resolved so far. Only approximately 47% of the EDMD patients can be linked to genes of LiNC and non‐LiNC components, probably interacting with muscle‐specific LiNC(s) involved in the pathology of muscular disorders.

Key Concepts:

Linker of nucleoskeleton and cytoskeleton (LiNC) complexes are tethering the nucleo‐ and cytoskeleton via the nuclear envelope.

The inhibition of LiNC components results in changes of the biomechanical behaviour of contractile cells.

Mutations in genes encoding muscle‐specific LiNC components lead to a variety of inherited human muscular disorders, in particular Emery–Dreifuss muscular dystrophy.

The wide phenotypic variability of LiNC‐associated muscular diseases can be explained by digenic inheritance.

The association of LiNC and LiNC‐related components with human disease helps to resolve genetic heterogeneity and clinical variability and provides tools to understand their functions within the cell as well.
Plakin Proteins, Hemidesmosomes and Human Disease
Authors: Chidgey Martyn
Published: April 2013

The plakin proteins are a family of cytolinker proteins that connect elements of the cell cytoskeleton to each other and to junctional complexes at the cell membrane. There are seven mammalian plakin proteins and they are characterised by the presence of a plakin domain and/or a plakin repeat domain. The plakins play a vital role in maintaining the integrity of tissues, such as the skin and heart, which are subjected to mechanical stress. Two plakin proteins, plectin and bullous pemphigoid antigen 1 (BPAG1), are essential components of hemidesmosomes, cell–extracellular matrix junctions of epithelial cells, and inherited mutations in either can result in the skin blistering disease epidermolysis bullosa simplex. Mutations in the desmosomal plakin protein desmoplakin can cause the heart muscle disorder arrhythmogenic right ventricular dysplasia, a common cause of sudden cardiac arrest and death in young adults. Plakin proteins are targeted by pathogenic autoantibodies in the skin blistering diseases bullous pemphigoid and paraneoplastic pemphigus.

Key Concepts:

The plakin proteins are a family of cytolinker proteins that connect elements of the cell cytoskeleton to each other and to junctional complexes at the cell membrane.

Seven plakin proteins are found in mammals; plectin, BPAG1, desmoplakin, envoplakin, periplakin, microtubule–actin crosslinking factor 1 and epiplakin.

Plectin and BPAG1 are important constituents of hemidesmosomes, cell–extracellular matrix junctions.

Mutations in plakin proteins can result in skin blistering disease, muscular dystrophy, autonomic neuropathy and cardiomyopathy.

Plakin proteins have been implicated in the autoimmune skin blistering diseases bullous pemphigoid and paraneoplastic pemphigus.
Evolution of Uric Acid Metabolism in Humans
Authors: Alvarez‐Lario Bonifacio , Macarrón‐Vicente Jesús
Published: April 2013

Several evolutionary changes have led to uric acid levels being much higher in humans than in other mammals. Uric acid is the end product of purine metabolism in hominoids, including humans, due to the genetic loss of uricase activity during the Miocene epoch, and this is the main cause of the increased uric acid in hominoids. Additional factors that have contributed to increased levels of uric acid are the high renal tubular reabsorption of uric acid and the previous loss of the ability to synthesise vitamin C in hominoids. Several hypotheses have been proposed on the evolutionary advantage of increased serum uric acid levels in hominoids, although the biological reasons for this increase remain unclear. The large current increase in uric acid levels in humans in developed countries is mainly influenced by dietary factors and lifestyle changes.

Key Concepts:

Uric acid (UA) is the end product of purine metabolism in humans due to the loss of uricase activity by various mutations of its gene during the Miocene epoch.

Loss of uricase activity led to humans having higher UA levels than other mammals.

The high renal tubular reabsorption of UA and the previous loss of the ability to synthesise vitamin C may have also contributed to increased levels of UA in humans.

The biological reason for the loss of uricase activity and increased levels of UA in humans and certain primates is unknown.

UA is one of the most important antioxidants in human biological fluids.

UA probably has neuroprotective activity.

The current large increase in UA levels in humans in developed countries is mainly influenced by eating habits and lifestyle changes.

Hyperuricaemia can cause gout and uric lithiasis, and is associated with hypertension, metabolic syndrome, renal disease and cardiovascular disease.
Tandem Repeat Instability and Genome Evolution
Authors: Matthew Ward R , Mittelman David
Published: April 2013

Evolvability is the potential for a biological system to produce variation that can be acted upon by natural selection. Processes that promote selectable variation can facilitate adaptation to dynamic environments. Microsatellite repeats – sequences composed of repeated sets of up to nine nucleotides – provide one source of adaptive variation. Repeats mutate by the addition or loss of their unit nucleotide sequence, up to 100 000 times more frequently than point mutations. In a number of species, including humans, repeat mutations can cause disease (including neurological and skeletal disorders) as well as exert subtle and quantitative consequences on gene function, morphology, behaviour and life history traits. Understanding the underlying properties of repeat mutation – including causes and mechanisms – is critical for understanding trait variation, adaptation and a growing list of human disorders.

Key Concepts:

Recent discoveries in molecular genetics are challenging current dogma that claims independence between selection and mutation.

Tandem repeats in the genome are highly mutable, sometimes at frequencies of up to 100 000 times more than point mutations.

Nearly all aspects of DNA processing, and even transcription and stress, contribute to repeat mutation, making repeats important markers for genomic instability.

Microsatellite repeats encode their own mutability, thereby enabling local manipulation of mutation rates.

Changes in the lengths of tandem repeats can subtly and quantitatively modulate gene function, traits and disease.

Many genomic regions, including tandem repeats, mutate during cellular stress, suggesting that the genome is far more dynamic and susceptible to environmental processes than previously recognised.
A Negative Conductivity Material Makes a dc Invisibility Cloak Hide an Object at a Distance
Authors: Yang Fan , Mei Zhong Lei , Yang Xin Yu , Jin Tian Yu , Cui Tie Jun
Published: April 2013

The theoretical design and the first experimental verification of an exterior dc invisibility cloak that can hide an object from dc detection at a distance are presented. Based on the transformation optics theory, the exterior dc cloak requires negative conductivity material to create folded geometry, which will cancel the real geometry of detected object in distance and make it invisible. Negative conductivities are designed and realized using active devices, together with resistor networks, to generate the equivalent conductivity materials required by the exterior dc cloak. An experimental sample of the dc cloak is fabricated on the printed circuit board and the measured result has excellent agreement with numerical and circuit simulations, showing very good cloaking performance at a distance.
Synthesis, crystal and electronic structure, anticancer activity of ruthenium(II) arene complexes with thiosemicarbazones
Authors: Su Wei , Zhou Quan , Huang Yanmin , Huang Qianyang , Huo Lini , Xiao Qi , Huang Shan , Huang Chusheng , Chen Rui , Qian Quanquan , Liu Lifeng , Li Peiyuan
Published: April 2013

A series of half‐sandwich ruthenium(II) arene complexes [(η6‐p‐cymene)RuII(R‐BzTSC)Cl]Cl 1, 2, 3 (BzTSC = benzaldehyde thiosemicarbazone and R = H, CH3 and C6H5) have been synthesized and characterized by IR, 1H NMR, UV‐visible, electrospray ionization mass spectrometry and elemental analysis. The single‐crystal structures of 1 and 3 have been determined. The molecular orbitals and electronic absorption spectra of the compounds have been calculated using the DFT and TDDFT methods. The in vitro antiproliferative activities of these complexes have been evaluated against four human cancer cell lines (CNE, H292, SKBR3 and Hey1‐B), and 3 is proved to be the most efficient inhibitor, with IC50 values of 20, 31, 10 and 34 μm, respectively. Copyright © 2013 John Wiley & Sons, Ltd.
Effect of interfacial tension on the cell structure of poly(methyl methacrylate)/bisphenol A polycarbonate blends foamed with CO2
Authors: Gong Pengjian , Ohshima Masahiro
Published: April 2013

A small amount of low‐decomposition temperature poly(methyl methacrylate), (low‐Td PMMA), can be used as a compatibilizer for high‐decomposition temperature PMMA (high‐Td PMMA) and polycarbonate (PC) blend systems. When low‐Td PMMA is thermally decomposed in the PMMA/PC blend, the PMMA‐g‐PC copolymer is formed. This copolymer decreases the interfacial tension between PMMA and PC, decreases the domain size of PC and increases the interfacial area. Blends of high‐Td PMMA/PC with different amounts of low‐Td PMMA undergo a batch physical foaming with CO2. With increasing amounts of low‐Td PMMA, which is equivalent to increasing the PMMA‐g‐PC copolymer, the number density of bubbles increases due to the increase of the interfacial area of disperse domains. However, the interfacial tension is decreased and the heterogeneity of PMMA/PC blend is decreased with increasing amounts of the copolymer. The number of bubbles per unit interfacial area and that per unit number of domains are decreased. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 39228.
Improved stability and tumor targeting of 5‐fluorouracil by conjugation with hyaluronan
Authors: Dong Zhikui , Zheng Wenyi , Xu Zaiyang , Yin Zongning
Published: April 2013

To circumvent the rapid clearance in vivo and consequent low tumor targeting of 5‐fluorouracil (5‐Fu), hyaluronan‐5‐fluorouracil conjugate (HA‐5‐Fu) was firstly synthesized and characterized. The stability of HA‐5‐Fu in vitro was evaluated by incubation with phosphate buffered saline, hyaluronidase solution, and mice plasma, respectively. The tumor targeting was tested by in vitro cytotoxicity evaluation and in vivo pharmacokinetics study in plasma and tumor. HA‐5‐Fu with drug loading of 87.674 mg/g was successfully obtained and confirmed. HA‐5‐Fu showed high stability in acidic environment and moderate stability under enzymatic cleavage. The enhanced cytotoxicity of HA‐5‐Fu over 5‐Fu depended on drug concentration, incubation time, and cell lines type. The t1/2 of HA‐5‐Fu in plasma after injection of prodrug was extended up to 10 times compared with that of 5‐Fu. Notably, AUC0–t in tumors of HA‐5‐Fu was 3.6 times higher than 5‐Fu, demonstrating its excellent tumor targeting and quite promising prospect in anti‐cancer therapy. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 927‐932, 2013
Chemical strategies to understand the language of ubiquitin signaling
Authors: Weller Caroline E. , Pilkerton Meagan E. , Chatterjee Champak
Published: April 2013

Ubiquitin (Ub) is a small 76 amino acid long protein that is highly conserved in all eukaryotes studied to date. In humans, more than 600 ligases are involved in the reversible modification of specific lysine side‐chain amines in substrate proteins by conjugation with the C‐terminal carboxylate of Ub. Initially monoubiquitylated proteins can undergo repetitive ubiquitylation starting from one of seven lysine residues or the α‐amine in the first Ub to generate a variety of polyUb chains with different topologies and functions. The most well known role for protein ubiquitylation is in targeting substrates for proteolytic destruction by 26S proteasomes. However, a growing body of evidence indicates that both mono‐ and polyubiquitylation play proteasome‐independent roles in modulating the structure, function, and localization of protein substrates. Understanding the complexity of Ub‐mediated functions in our cells is a major challenge for modern biology. In addition to well‐established in vivo genetic methods, biochemical and biophysical investigations of ubiquitylated proteins in vitro can shed light on the direct mechanistic roles for Ub in different contexts. Such studies have traditionally been limited by the ability to obtain sufficient quantities of homogenously ubiquitylated proteins with precisely defined linkages. This review focuses on recent advances in both synthetic and recombinant protein‐based methods that have yielded access to homogenously site‐specifically ubiquitylated proteins. Mechanistic studies of the roles for protein ubiquitylation and of the enzymes involved in protein deubiquitylation that are enabled by these chemical tools are highlighted. © 2013 Wiley Periodicals, Inc. Biopolymers 101: 144–155, 2014.
ChemInform Abstract: (Sb7Te8)5+ — A Double Cube Shaped Polycationic Cluster.
Authors: Eich Andreas , Schlueter Stefan , Schnakenburg Gregor , Beck Johannes
Published: April 2013

Orange, highly air sensitive crystals of (Sb7Te8)[Ga2Cl7]2 [GaCl4]3 (I), (Sb7Te8)[Ga2Cl7]3 [GaCl4]2 (II), Na(Sb7Te8)[GaCl4]6 (III) and Na(Sb7Te8)[AlCl4]6 (IV) are prepared by reaction of Sb and Te in molten GaCl3 or AlCl3 in the presence of MCl (M: Li, Na, In, Cu) and SbCl3 as the oxidant (I: 100°C, 15 d, II: 100°C, 60 d, III: 100°C, 69 d, IV: 125°C, 15 d).
ChemInform Abstract: Oxidative Rearrangement of Tertiary Propargylic Alcohols.
Authors: Rodriguez Arantxa , Moran Wesley J.
Published: April 2013

The process generates highly substituted acrylic acids in low to moderate yields.
ChemInform Abstract: Asymmetric Synthesis of 4‐Formyl‐1‐(ω‐haloalkyl)‐β‐lactams and Their Transformation to Functionalized Piperazines and 1,4‐Diazepanes.
Authors: Dekeukeleire Stijn , D'hooghe Matthias , Vanwalleghem Matthieu , Van Brabandt Willem , De Kimpe Norbert
Published: April 2013

The chiral piperazine (III) and 1,4‐diazepane annulated β‐lactams (VII) are transformed into the novel compounds (V) and (VIII) via ring opening.
ChemInform Abstract: Michael Addition of N‐Heteroaromatics to Vinylphosphonates and Synthesis of Phosphoryl Pyrrolizones by Cyclization of Michael Adducts.
Authors: Tasgin Dilek Isik , Unaleroglu Canan
Published: April 2013

The conversion of Knoevenagel products to N‐hetaryl‐substituted vinylphosphonates is developed.
ChemInform Abstract: Synthesis and Photoluminescent Properties of New Aza‐Indenofluorene Derivatives.
Authors: Jung Su Jin , Kim Won Sam , Park Byung Sun , Lee Jae Kyun , Park Jung Hwan , Choi Kihang , Lee So Ha
Published: April 2013

Several new carbazole derivatives (VII), (IX) are synthesized via Suzuki coupling of boronic acid (I) with 1‐bromo‐2‐nitrobenzene (II), followed by the Cadogan ring closure reaction.
ChemInform Abstract: New Thiochromans via Reductive Cyclization of Thiophenol Derivatives.
Authors: Niermann Andre , Groessel Janine E. , Reissig Hans‐Ulrich
Published: April 2013

The samarium diiodide induced cyclization of sulfur‐containing precursors to produce thiochroman systems is investigated.
ChemInform Abstract: Double Palladium‐Catalyzed Synthesis of Azepines.
Authors: Bozinovic Nina , Opsenica Igor , Solaja Bogdan A.
Published: April 2013

A convenient method is developed for the Pd‐catalyzed double amination reaction of substrates (I) to form azepine derivatives.
ChemInform Abstract: Facile Synthesis and Estrogenic Activity of Arylpyrrole‐Based Bisphenol Derivatives.
Authors: Ohta Kiminori , Taguchi Fumi , Endo Yasuyuki
Published: April 2013

Derivatives (V) and (VI) bond weakly to ERα and exhibit estrogenic activity in MCF‐7 cell proliferation assay.
ChemInform Abstract: Magnetic Semiconductor EuO, EuS, and EuSe Nanocrystals for Future Optical Devices
Authors: Hasegawa Yasuchika
Published: April 2013

Review: ≈80 refs.
ChemInform Abstract: Zinc‐Catalyzed Organic Synthesis: C—C, C—N, C—O Bond Formation Reactions
Authors: Wu Xiao‐Feng , Neumann Helfried
Published: April 2013

Review: 129 refs.
ChemInform Abstract: Catalytic C‐H Bond Activation Reactions
Authors: Tomin Anna , Bag Seema , Torok Bela
Published: April 2013

Review: 232 refs.
ChemInform Abstract: Asymmetric Intra‐ and Intermolecular Pauson—Khand Reactions: The Chiral Auxiliary Approach
Authors: Moyano Albert
Published: April 2013

Review: 104 refs.
Hydrodynamics of High Pressure Bubble Columns
Authors: Rollbusch Philipp , Tuinier Martin , Becker Marc , Ludwig Martina , Grünewald Marcus , Franke Robert
Published: April 2013

Die Hydrodynamik einer Blasensäule beeinflusst Größen wie Umsatz, Selektivität und Ausbeute einer Reaktion. Besondere Bedeutung erlangen die Rückvermischung der flüssigen Phase und der Gehalt an disperser Gasphase. Zur Ermittlung dieser Parameter steht eine Vielzahl an Korrelationen in der Literatur zur Verfügung. Diese Korrelationen wurden oftmals von Versuchsanlagen im Labormaßstab abgeleitet, die nicht unter industriell relevanten Bedingungen betrieben wurden. In diesem Beitrag wird der Stand der vorhandenen Untersuchungen an Blasensäulen hinsichtlich Gasgehalt und Dispersion unter erhöhtem Druck dargestellt und eine Empfehlung für weiterführende Untersuchungen gegeben.
Efficient and robust identity‐based handoff authentication for EAP‐based wireless networks
Authors: Han Qi , Zhang Yinghui , Chen Xiaofeng , Li Hui , Quan Jiaxiang
Published: April 2013

The Extensible Authentication Protocol (EAP) framework aims to realize a flexible authentication for wireless networks. However, a full EAP authentication needs several round trips between a mobile node and the EAP server, and hence is unacceptable in a process of handoff authentication because of inefficient performance. Considering the advantage of the identity‐based cryptography, it is attractive to realize handoff authentication efficiently in the identity‐based setting. In this work, we propose a new identity‐based handoff authentication scheme in which a special double‐trapdoor chameleon hash function is used. Compared with the existing identity‐based handoff authentication construction, the main advantage of the proposed scheme eliminates the assumption that the private key generator is fully trusted. Besides, the detailed security analysis shows that the proposed scheme not only satisfies robust security properties but also enjoys desirable efficiency for the real‐world applications. Copyright © 2013 John Wiley & Sons, Ltd.
Managing diversity: Domestication and gene flow in Stenocereus stellatus Riccob. (Cactaceae) in Mexico
Authors: Cruse‐Sanders Jennifer M. , Parker Kathleen C. , Friar Elizabeth A. , Huang Daisie I. , Mashayekhi Saeideh , Prince Linda M. , Otero‐Arnaiz Adriana , Casas Alejandro
Published: April 2013

Microsatellite markers (N = 5) were developed for analysis of genetic variation in 15 populations of the columnar cactus Stenocereus stellatus, managed under traditional agriculture practices in central Mexico. Microsatellite diversity was analyzed within and among populations, between geographic regions, and among population management types to provide detailed insight into historical gene flow rates and population dynamics associated with domestication. Our results corroborate a greater diversity in populations managed by farmers compared with wild ones (HE = 0.64 vs. 0.55), but with regional variation between populations among regions. Although farmers propagated S. stellatus vegetatively in home gardens to diversify their stock, asexual recruitment also occurred naturally in populations where more marginal conditions have limited sexual recruitment, resulting in lower genetic diversity. Therefore, a clear‐cut relationship between the occurrence of asexual recruitment and genetic diversity was not evident. Two managed populations adjacent to towns were identified as major sources of gene movement in each sampled region, with significant migration to distant as well as nearby populations. Coupled with the absence of significant bottlenecks, this suggests a mechanism for promoting genetic diversity in managed populations through long distance gene exchange. Cultivation of S. stellatus in close proximity to wild populations has led to complex patterns of genetic variation across the landscape that reflects the interaction of natural and cultural processes. As molecular markers become available for nontraditional crops and novel analysis techniques allow us to detect and evaluate patterns of genetic diversity, genetic studies provide valuable insights into managing crop genetic resources into the future against a backdrop of global change. Traditional agriculture systems play an important role in maintaining genetic diversity for plant species.
Optimization of magnet arrangement in double‐layer interior permanent‐magnet motors
Authors: Yamazaki Katsumi , Kitayuguchi Kazuya
Published: April 2013

The arrangement of permanent magnets in double‐layer interior permanent‐magnet motors is optimized for variable‐speed applications. First, the arrangement of magnets is decided by automatic optimization. Next, the superiority of the optimized motor is discussed by considering d‐ and q‐axis equivalent circuits that take into account the magnetic saturation of the rotor core. Finally, experimental veriﬁcation is carried out with a prototype motor. It is conﬁrmed that the maximum torque of the optimized motor under both low‐speed and high‐speed conditions is higher than that of conventional motors because of the relatively large q‐axis inductance and small d‐axis inductance. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(4): 54–63, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22348
Inverter for interchangeable use as current source inverter and voltage source inverter for interconnecting to grid
Authors: Teraya Daisuke , Masukawa Shigeo , Iida Shoji
Published: April 2013

We propose a novel inverter that can be operated either as a current source inverter (CSI) or as a voltage source inverter (VSI) by changing only the control signals. It is proper to use it for interconnecting systems with renewable energy, such as photovoltaic cells or wind generation systems, to a grid. This inverter is usually operated as a CSI connected to the grid. Even if the energy source has a lower voltage than the grid, energy can be supplied to the grid through the proposed inverter. The power factor can be brieﬂy maintained close to unity. When power supply from the grid is interrupted, the proposed circuit should be operated as a VSI in the stand‐alone operation mode. In this way, the circuit can maintain a constant output voltage to the loads. In this paper, the proposed circuit conﬁguration and the control schemes for both the CSI and the VSI are described. The circuit characteristics for both are also discussed experimentally. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(4): 45–53, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22349
Application of a modular multilevel cascade converter (MMCC‐SDBC) to a STATCOM. Control of active power and negative‐sequence reactive power
Authors: Hagiwara Makoto , Maeda Ryo , Akagi Hirofumi
Published: April 2013

This paper presents the application of a modular multilevel cascade converter based on single‐delta bridge‐cells (MMCC‐SDBC) to a STATic synchronous COMpensator (STATCOM), particularly for negative‐sequence reactive‐power control. The SDBC is characterized by cascade connection of multiple single‐phase H‐bridge (or full‐bridge) converter cells per leg, which facilitates ﬂexible circuit design, low voltage steps, and low electromagnetic interference (EMI) emissions. However, there is no published report on such a STATCOM with experimental veriﬁcation or a control strategy. This paper designs, constructs, and tests a 100‐V 5‐kVA PWM STATCOM based on the SDBC with focus on the operating principle and performance. Experimental results conﬁrm that this converter can control not only the positive‐sequence reactive power but also the negative‐sequence reactive power and low‐frequency active power intended for the ﬂicker compensation of arc furnaces. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(4): 33–44, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22365
First Homoleptic Complexes of the Tridentate Pyridine‐2,6‐ditetrazolate Ligand
Authors: Klein Axel , Krest Alexander , Nitsche Sara , Stirnat Kathrin , Valldor Martin
Published: April 2013

The synthesis and spectroscopic characterisation of a series of homoleptic complexes of the tridentate pyridine‐2,6‐di(5‐tetrazolate) ligand (pydtz2–) with CoII, NiII, CuII and ZnII are reported. Single‐crystal XRD data reveals the formation of octahedrally configured complexes [M(pydtz)2]2– for M = Zn or [M(Hpydtz)(pydtz)]– for M = Co or Ni, whereas for M = Cu a polymeric structure [Cu(pydtz)(EtOH)]n crystallised. In the latter, alternate short and long Cu···Cu distances were found. Magnetic measurements and electron paramagnetic resonance (EPR) spectroscopy reveal noncoupled S = 1/2 CuII ions for [Cu(pydtz)(EtOH)]n, S = 1/2 low‐spin configuration for the CoII complex and an S = 1 ground state for the NiII derivative. At T < 16 K the latter shows anomalies that resemble those of single‐ion molecular magnets. The ligand strength of pydtz2– is markedly higher than that of the bioisosteric pyridine‐2,6‐dicarboxylate (pydic2–) ligand and is very similar to that of the well‐established 2,2′:6′,2″‐terpyridine (terpy) ligand as revealed by the ligand field bands of the Co, Ni and Cu complexes and the magnetism of the Co and Ni derivatives. Solution electrochemical investigations suggest that essentially ligand‐centred reduction at rather negative potentials and metal‐centred oxidation processes occur.
High Temperature Co‐Electrolysis of Steam and CO2 in an SOC Stack: Performance and Durability
Authors: Chen M. , Høgh J. V. T. , Nielsen J. U. , Bentzen J. J. , Ebbesen S. D. , Hendriksen P. V.
Published: April 2013

In this work, co‐electrolysis of steam and carbon dioxide was studied in a Topsoe Fuel Cell (TOFC®) 10‐cell stack, containing three different types of Ni/yttria stabilized zirconia (YSZ) electrode supported solid oxide electrolysis cells with a footprint of 12 × 12 cm. The stack was operated at 800 °C and –0.75 A cm–2 with 60% conversion for a period of 1,000 h. One type of the cells showed no long term degradation but actually activation during the entire electrolysis period, while the other two types degraded. The performance and durability of the different cell types is discussed with respect to cell material composition and microstructure. The results of this study show that long term electrolysis is feasible without notable degradation at 800 °C and a current density of –0.75 A cm–2.
The role of excess subcutaneous fat in pain and sensory sensitivity in obesity
Authors: Price R.C. , Asenjo J.F. , Christou N.V. , Backman S.B. , Schweinhardt P.
Published: April 2013

Background

Previous studies suggest pain sensitivity may be decreased in obesity, but it is unknown whether this is a global or a site‐specific phenomenon related to the amount of excess fat.

Methods

Design: a cross‐sectional study comparing obese and non‐obese participants on body sites with much and little excess subcutaneous fat in obesity. Hot and cold sensory detection thresholds, pain thresholds, pain tolerance and subjective ratings for a cold (0 °C) and hot (48 °C) stimulus were assessed using a 16 × 16 mm thermode (Medoc, Israel) on the forehead and abdomen. Pressure pain thresholds were measured on the hand. Cold water immersion tolerance duration and subjective ratings were assessed on the hand. Two indices of central pain processing, i.e., temporal summation and heterotopic noxious stimulation, were assessed.

Results

A total of 20 obese participants [10M/10F, BMI mean (SD) = 41.5 kg/m2 (9.4 kg/m2)] and 20 age‐ and gender‐matched non‐obese controls [10M/10F, BMI mean (SD) = 23.5 kg/m2 (2.9 kg/m2)] were studied. Compared with non‐obese, obese participants had higher thresholds and lower subjective ratings, indexing decreased sensitivity, for painful and non‐painful thermal stimuli on the abdomen, an area with much excess subcutaneous fat. Decreases in abdominal sensitivity correlated with measures of adiposity (i.e., waist‐to‐hip ratio and subcutaneous fat thickness). On areas with little excess subcutaneous fat (forehead and hand), obese and non‐obese groups did not differ in measures of thermal or pressure sensitivity, nor for indices of central pain processing.

Conclusion

Obese participants are less sensitive than non‐obese individuals, but only on areas with excess subcutaneous fat.
Phasor analysis of multiphoton spectral images distinguishes autofluorescence components of in vivo human skin
Authors: Fereidouni Farzad , Bader Arjen N. , Colonna Anne , Gerritsen Hans C.
Published: April 2013

Skin contains many autofluorescent components that can be studied using spectral imaging. We employed a spectral phasor method to analyse two photon excited autofluorescence and second harmonic generation images of in vivo human skin. This method allows segmentation of images based on spectral features. Various structures in the skin could be distinguished, including Stratum Corneum, epidermal cells and dermis. The spectral phasor analysis allowed investigation of their fluorescence composition and identification of signals from NADH, keratin, FAD, melanin, collagen and elastin. Interestingly, two populations of epidermal cells could be distinguished with different melanin content. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A silicon photonic biosensor using phase‐shifted Bragg gratings in slot waveguide
Authors: Wang Xu , Flueckiger Jonas , Schmidt Shon , Grist Samantha , Fard Sahba T. , Kirk James , Doerfler Matt , Cheung Karen C. , Ratner Daniel M. , Chrostowski Lukas
Published: April 2013

We present a novel silicon photonic biosensor using phase‐shifted Bragg gratings in a slot waveguide. The optical field is concentrated inside the slot region, leading to efficient light‐matter interaction. The Bragg gratings are formed with sidewall corrugations on the outside of the waveguide, and a phase shift is introduced to create a sharp resonant peak within the stop band. We experimentally demonstrate a high sensitivity of 340 nm/RIU measured in salt solutions and a high quality factor of 1.5 × 104, enabling a low intrinsic limit of detection of 3 × 10–4 RIU. Furthermore, the silicon device was fabricated by a CMOS foundry, facilitating high‐volume and low‐cost production. Finally, we demonstrate the device's ability to interrogate specific biomolecular interactions, resulting in the first of its kind label‐free biosensor. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Production enhancement of 5‐hydroxymethyl furfural from fructose via mechanical stirring control and high‐fructose solution addition
Authors: Jiang Nan , Qi Wei , Huang Renliang , Wang Mengfan , Su Rongxin , He Zhimin
Published: April 2013

BACKGROUND

5‐hydroxymethylfurfural (HMF) has attracted increasing attention so that an efficient process for HMF production from high‐sugar solution is needed for the successful commercialization of this versatile intermediate in the production of high value chemicals.

RESULTS

Two simple operations, mechanical stirring control and high‐fructose solution addition, were applied to the water/butanol system for enhancing fructose‐to‐HMF reaction using HCl as catalyst. The optimization of stirring speed led to a high HMF yield of 81.7% with 92.0% fructose conversion (0.3 moL L−1 HCl, 1000 rpm). Moreover, a reasonable mechanism describing the effect of stirring speed on HMF yield was proposed. During the process of high‐fructose solution (54.6 wt%) addition, the yields of HMF after four additions in every experiment all exceeded 55%, and a HMF yield of 83.3% was achieved after three additions at 1000 rpm.

CONCLUSIONS

The optimization of mechanical stirring in aqueous/butanol media led to a high HMF yield. By studying the kinetics of the fructose‐to‐HMF reaction, it was demonstrated that a low value of reaction rate constant is of benefit to obtain high HMF yield for this biphasic system. The simple addition process greatly reduced the side‐reaction and made the operation more continuous and stable, and thus provided a practical and effective method of HMF preparation in high‐fructose solution. © 2013 Society of Chemical Industry
Coal tar recovery using enhanced ‘pump‐and‐treat’
Authors: Kostarelos Konstantinos , Yoon Sungho , Lee Kenneth Y.
Published: April 2013

BACKGROUND

Most experts acknowledge that low aqueous solubility results in low mass recovery rates using pump‐and‐treat (P&T), making such systems ineffective for coal tar (a multi‐component NAPL) recovery. It is proposed to increase the apparent aqueous solubility of coal tar by orders of magnitude as an enhancement to conventional P&T schemes (or ‘P&T–E’), increasing coal tar recovery rates, reducing the pore volumes and time required for complete recovery, thus translating into cost savings.

RESULTS

Batch test results of aqueous solutions containing anionic surfactant, co‐solvent, and electrolyte are presented that were studied for both compatibility with a field‐obtained coal tar and effectiveness at solubilizing the coal tar above its aqueous solubility. Seven surfactants were tested at room temperature (23C) in aqueous solutions containing the surfactant with co‐solvents and electrolytes. The most promising surfactant solution solubilized upwards of 40 000 mg L−1 coal tar. A 1–D column test resulted in 97% recovery using the promising surfactant.

CONCLUSIONS

P&T–E could significantly increase coal tar solubility without causing the formation of a rate‐limiting, solid‐like film and offers a promising approach for the remediation of coal tar from the subsurface. © 2013 Society of Chemical Industry
Identifying the active phase in Cs‐promoted MgO nanocatalysts for triglyceride transesterification
Authors: Woodford Julia J. , Parlett Christopher M.A. , Dacquin Jean‐Philippe , Cibin Gianantonio , Dent Andrew , Montero Janine , Wilson Karen , Lee Adam F.
Published: April 2013

Background

Biodiesel is a clean‐burning, renewable and biodegradable diesel fuel substitute derived from animal fats and plant oils, which may play an important role in replacing diminishing fossil fuel reserves and combating climate change. Conventional biodiesel production uses soluble base catalysts, such as Na or K alkoxides, to convert oils into fuel, and as a result requires energy intensive aqueous quench cycles to isolate the biodiesel product.

Results

Cs‐doping nanoparticulate MgO, prepared via a novel, supercritical sol–gel method, yields a solid base catalyst with improved activity for the transesterification of pure triacylglycerides (TAGs) and olive oil.

Conclusion

Here, X‐ray absorption spectroscopy (XAS) is used to probe the local chemical environment of Cs atoms in order to identify the nature of the catalytically active species as Cs2Mg(CO3)2(H2O)4. © 2013 Society of Chemical Industry