bluuebunny/crossref_metadata_2025 huggingface dataset:
Priority areas to collect germplasm ofMalacomeles(Rosaceae) in Mexico based on diversity and species richness indices
Authors: Núñez-Colín Carlos A. , Hernández-Martínez Miguel Á. , Escobedo-López Diana , Ortega-Rodríguez Carlos
Published: May 2012

The genusMalacomeles(Decne.) G. N. Jones (RosaceaesubtribePyrinae) represents several fruit shrubs, which is mainly distributed in North and Central America, from southern USA to Honduras and Guatemala, although the main distribution of this genus is in Mexico. Five species of the genusMalacomeleshave been reported to exist in Mexico.Malacomelesis widely distributed in several mountainous ranges in Mexico, although it is unknown where most of the diversity of theMalacomelesgenus is located in the country. The aim of this biogeographic study was to determine the areas of highest diversity of the genusMalacomelesin Mexico based on species richness and diversity indices in order to identify the best regions of Mexico to collect germplasm. The results indicated that most of the diversity of the genusMalacomelesis concentrated in northeast Mexico, mainly in the biogeographic province of Sierra Madre Oriental. In this province, the highest values on three biodiversity indices were found. Thus, this area can be considered as the priority area to collect the germplasm ofMalacomeles.M. denticulatais the predominant and the most interesting species in Mexico from the viewpoint of collecting plant genetic resources; this species is mainly distributed in the provinces of Trans-Mexican Volcanic Axis, Mexican Plateau and Sierra Madre del Sur, where secondary priority areas to collect germplasm are located.
Reliability of germination testing of ex situ conserved seeds: a genebank case study on outsourced analyses
Authors: van Hintum Theo , van Treuren Rob
Published: May 2012

Germination tests are performed on a routine basis to determine the viability of genebank accessions. The results determine which accessions have to be rejuvenated. The reliability of the germination test results used by the Centre for Genetic Resources, the Netherlands was determined by the retesting of 641 random samples anonymously, in the same year and by the same testing agency as the original tests. Results showed alarmingly low reliabilities, with error levels much higher than expected based on sampling effects. The result of a germination test of a random sample with a germination of 80% was shown to have a 95% confidence interval from 63 to 97%. The errors differed strongly over crops and testing years, and were larger for crop wild relatives than for crop species.
Enhancement of coccolithophorid blooms in the Bering Sea by recent environmental changes
Authors: Harada Naomi , Sato Miyako , Oguri Kazumasa , Hagino Kyoko , Okazaki Yusuke , Katsuki Kota , Tsuji Yoshinori , Shin Kyung‐Hoon , Tadai Osamu , Saitoh Sei‐Ichi , Narita Hisashi , Konno Susumu , Jordan Richard W. , Shiraiwa Yoshihiro , Grebmeier Jacqueline
Published: May 2012

Since 1997, ocean color satellite images have revealed large‐scale blooms of the coccolithophorid Emiliania huxleyi in the eastern Bering Sea. The blooms are often sustained over several months and have caused ecosystem changes in the Arctic Ocean, as well as in the Bering Sea. We examined continental shelf sediment profiles of alkenone, a biomarker for E. huxleyi, covering the past ∼70 years. The alkenone records suggest that large E. huxleyi blooms are a novel feature in the Bering Sea as they have occurred only since the late 1970s. Recent changes in alkenone content were closely related to the 1976–77 climatic regime shift in the North Pacific, implying that warming and freshening of Bering Sea waters promoted E. huxleyi blooms. The production rate of diatoms (total valves in sediment samples), the dominant primary producers in the Bering Sea, also increased during the past several decades. However, the ratio of alkenone content to total diatom valves in the sediments increased as E. huxleyi production increased, suggesting that the increase in the E. huxleyi production rate frequently exceeded the increase in the diatom production rate. Overall, our results indicate a possible subarctic region ecosystem shift driven by climate change.
Aquitard contaminant storage and flux resulting from dense nonaqueous phase liquid source zone dissolution and remediation
Authors: Brown Gordon H. , Brooks Michael C. , Wood A. Lynn , Annable Michael D. , Huang Junqi
Published: May 2012

A one‐dimensional diffusion model was used to investigate the effects of dense nonaqueous phase liquid (DNAPL) source zone dissolution and remediation on the storage and release of contaminants from aquitards. Source zone dissolution was represented by a power law source depletion model, which served as a time variable boundary condition to the diffusion equation used to describe mass transport in the aquitard. Two key variables were used to assess source zone dissolution behavior on aquitard mass storage and release: the power law exponential term Γ, which reflects the influence of the source zone architecture, and a new variable defined herein as the source to aquitard mass transfer coefficient β, which reflects the influences of both the source characteristics and the aquitard media properties. As Γ increased or as β increased because of more rapid source dissolution, the aquitard concentrations, depth of penetration, and long‐term back‐diffusion flux decreased. However, when β increased because of increased sorption, concentrations and back diffusion increased but penetration decreased. The duration of aquitard mass loading was found to be significantly less than the duration of mass release. Moreover, the mass per unit area stored in the aquitard was 3 or more orders of magnitude less than the initial DNAPL source zone mass per unit area, and the back diffusion flux from the aquitard was typically 4 or more orders of magnitude less than the initial source zone flux. Additionally, the effects of partial source zone remediation were investigated, and the results suggest that source remediation can have a favorable effect on long‐term back‐diffusion risk.
Low‐frequency variability of tropical cyclone‐induced heavy rainfall over East Asia associated with tropical and North Pacific sea surface temperatures
Authors: Lee Min‐Hee , Ho Chang‐Hoi , Kim Joo‐Hong , Song Hyo‐Jong
Published: May 2012

This study investigates the relationship between tropical cyclone (TC)–induced heavy rainfall over East Asia (EA) and large‐scale climate variability during June–October for the period of 1961–2005. An empirical orthogonal function analysis is applied to the seasonal‐total TC‐induced heavy rainfall obtained in meteorological stations over EA. The first leading mode shows a dipole pattern between South China (SC) and Northeast Asia (NEA; i.e., Southeast‐East China, Taiwan, and Japan). This dipole pattern is found to be associated with the two modes of sea surface temperature (SST) variations over the Pacific: one in the tropical Pacific, and the other spanning from EA to the North Pacific Ocean. The former is located in the NINO4 region, while the latter is characterized by the North Pacific center of the Pacific Decadal Oscillation (PDO). The dipole mode is generally well explained by the combined NINO4 and PDO impacts on TC tracks. During positive NINO4, cyclonic steering flows appear over inshore Southeast China, which increases recurving TCs. Meanwhile, the midlatitude North Pacific SST warming during negative PDO is overlaid by the barotropic anticyclone. The anomalous steering easterlies along 20°–40°N related to the anticyclone increase TC occurrence toward Southeast‐East China and Taiwan. Furthermore, the precipitable water greatly increases in the midlatitude ocean during negative PDO years, which may help to enhance the rainfall amount while TCs approach Japan. To sum up, in a climatological sense, the first mode of TC‐induced heavy rainfall over EA can be interpreted by the combined variations of negative (positive) PDO with positive (negative) NINO4.
Ostracode Mg/Ca paleothermometry in the North Atlantic and Arctic oceans: Evaluation of a carbonate ion effect
Authors: Farmer Jesse R. , Cronin Thomas M. , Dwyer Gary S.
Published: May 2012

The reconstruction of deep‐sea bottom water temperature (BWT) is important to assess the ocean's response to and role in orbital‐ and millennial‐scale climate change. Deep‐sea paleothermometry employs magnesium to calcium (Mg/Ca) ratios in calcitic benthic microfaunas (foraminifera, ostracodes) as a primary proxy method. Mg/Ca paleothermometry may, however, be complicated by bottom water carbonate ion chemistry, which might affect Mg/Ca ratios in shells. To address temperature and carbonate ion influence on Mg/Ca ratios, we studied Mg/Ca ratios in the benthic ostracode genus Krithe in the North Atlantic and Arctic oceans using a 686‐specimen core top collection, including 412 previously unpublished analyses. Mg/Ca ratios are positively correlated to temperature in multiple species from the North Atlantic [BWT = (0.885 × Mg/Ca) − 5.69, r2 = 0.73] and for K. glacialis in the Arctic Ocean and Nordic Seas [BWT = (0.439 × Mg/Ca) − 5.14, r2 = 0.50], consistent with previously published calibrations. We found no evidence for a relationship between Krithe Mg/Ca and carbonate ion saturation in the North Atlantic Ocean, Nordic Seas, and Arctic Ocean, supporting the use of Krithe Mg/Ca for reconstructing past BWT.
Tätowierungen – kein harmloser
Hautschmuck
Authors: Weiß J.
Published: May 2012

Tattoos sind in. Aber nicht unbedingt unproblematisch:
Untersuchungen zeigten kürzlich, dass einige der verwendeten
Farbstoffe nicht so unbedenklich sind, wie gemeinhin
angenommen. Und dann wäre da noch das Problem, unliebsam
gewordene Tätowierungen wieder zu entfernen. Denn dies ist
nicht ohne Weiteres möglich.
Variations in methanobactin structure influences copper utilization by methane-oxidizing bacteria
Authors: El Ghazouani Abdelnasser , Baslé Arnaud , Gray Joe , Graham David W. , Firbank Susan J. , Dennison Christopher
Published: May 2012

Methane-oxidizing bacteria are nature’s primary biological mechanism for suppressing atmospheric levels of the second-most important greenhouse gas via methane monooxygenases (MMOs). The copper-containing particulate enzyme is the most widespread and efficient MMO. Under low-copper conditions methane-oxidizing bacteria secrete the small copper-binding peptide methanobactin (mbtin) to acquire copper, but how variations in the structures of mbtins influence copper metabolism and species selection are unknown. Methanobactins have been isolated from
Methylocystis
strains M and
hirsuta
CSC1, organisms that can switch to using an iron-containing soluble MMO when copper is limiting, and the nonswitchover
Methylocystis rosea
. These mbtins are shorter, and have different amino acid compositions, than the characterized mbtin from
Methylosinus trichosporium
OB3b. A coordinating pyrazinedione ring in the
Methylocystis
mbtins has little influence on the Cu(I) site structure. The
Methylocystis
mbtins have a sulfate group that helps stabilize the Cu(I) forms, resulting in affinities of approximately 10
21
 M
-1
. The Cu(II) affinities vary over three orders of magnitude with reduction potentials covering approximately 250 mV, which may dictate the mechanism of intracellular copper release. Copper uptake and the switchover from using the iron-containing soluble MMO to the copper-containing particulate enzyme is faster when mediated by the native mbtin, suggesting that the amino acid sequence is important for the interaction of mbtins with receptors. The differences in structures and properties of mbtins, and their influence on copper utilization by methane-oxidizing bacteria, have important implications for the ecology and global function of these environmentally vital organisms.
Distinct contributions of the amygdala and parahippocampal gyrus to suspicion in a repeated bargaining game
Authors: Bhatt Meghana A. , Lohrenz Terry , Camerer Colin F. , Montague P. Read
Published: May 2012

Humans assess the credibility of information gained from others on a daily basis; this ongoing assessment is especially crucial for avoiding exploitation by others. We used a repeated, two-person bargaining game and a cognitive hierarchy model to test how subjects judge the information sent asymmetrically from one player to the other. The weight that they give to this information is the result of two distinct factors: their baseline suspicion given the situation and the suspicion generated by the other person’s behavior. We hypothesized that human brains maintain an ongoing estimate of the credibility of the other player and sought to uncover neural correlates of this process. In the game, sellers were forced to infer the value of an object based on signals sent from a prospective buyer. We found that amygdala activity correlated with baseline suspicion, whereas activations in bilateral parahippocampus correlated with trial-by-trial uncertainty induced by the buyer’s sequence of suggestions. In addition, the less credible buyers that appeared, the more sensitive parahippocampal activation was to trial-by-trial uncertainty. Although both of these neural structures have previously been implicated in trustworthiness judgments, these results suggest that they have distinct and separable roles that correspond to their theorized roles in learning and memory.
A review of the structure and regulation of the laying hen's reproductive system and the interaction between the stress and reproductive axes.
Authors: Golden J. B. , Arbona D. V.
Published: May 2012

The laying hen's ovary is a unique biological model for studying the interaction of the reproductive (hypothalamic-pituitary-gonadal (HPG)) and stress (hypothalamic-pituitary-adrenal (HPA)) axes because of the highly regulated, grossly apparent hierarchical organization of ovarian follicles destined for maturation and ovulation. Additionally, the histological structure of the hen's pre-ovulatory hierarchical follicles allows for the manual separation of the theca and granulosa tissues with ease, making it an ideal model for conducting gene expression studies that are tissue-specific in avian species. Through follicular gene expression studies, the processes of vitellogenesis, follicular maturation, selection and ovulation have been thoroughly characterized in the laying hen. More recently, an interest in understanding the impact of stress on follicular development has arisen in the poultry industry given producers' desires to maximize production efficiency. Specifically, the role of glucocorticoids and the expression of glucocorticoid receptors (GRs) on avian ovarian follicles have been examined to closely assess the interaction of the HPG and the HPA axes. By understanding the interaction of these axes, a better understanding of the impact of stress on layer hens' ovarian function will be gleaned. In this review, the hen's reproductive system as well as reproductive and stress axes are covered extensively in order to provide insight into the dynamic interactions that exist between the hen's ovarian follicles and primary stress hormone, corticosterone.
Theoretical Study on Electronic Gain-and-loss Properties of TEMPO and Its Derivates in Charge/Discharge Processes
Authors: Mao Shu-cai , Qu Jin-qing , Zheng Kang-cheng
Published: May 2012

Theoretical study on the electronic structures and related properties of 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and its cationic lipid derivates in the charge/discharge processes has been carried out using the density functional theory (DFT) at the (U)B3LYP/6-31G(d,p) or 6-31+G(d,p) level. The changes and regularities of geometric and electronic properties of these compounds in the charge/discharge processes were revealed in detail. The computational results show that the substitute group plays a very important role in the electronic structures and related properties of TEMPOs during the charge/discharge processes. It is very interesting to find that after getting an electron, TEMPO is more stable in singlet state but the lipid is more stable in triplet state. For TEMPO, both the charge and the discharge processes greatly influence the electronic properties of N and O atoms of the radical part. For the cationic lipid, the discharge process mainly influences the pyridinium head and the charge process mainly influences the free radical head. Moreover, the solvent effect plays an important role in some bond lengths and the charge population of the free radical head. In addition, the UV-Vis absorption spectra of TEMPO and the lipid were calculated and simulated using TDDFT at the 6-31G(d,p) or 6-31+G(d,p) level, in satisfying agreement with the experimental ones.
Accuracy of Low-level Surface in Hierarchical Construction of Potential Energy Surface
Authors: Wang Chun-rui , Zhang Dong H.
Published: May 2012

The effects of low-level PES on the overall accuracy of the final surface constructed by using hierarchical construction were investigated with the constructions of a number of global surfaces for the H3 system at UHF (UMP2, DFT-B3LYP, UCCSD(T))/vtz, and UCCSD(T)/avqz levels of theory. The total reaction probabilities for the H+H2 reaction calculated on these surfaces revealed that the accuracy of UCCSD(T)/avqz surface is very close to the well-known BKMP2 surface, while the UCCSD(T)/vtz PES has a slightly higher barrier. In contrast, the low-level theories (UHF, UMP2, DFT-B3LYP) with vtz basis set can only provide a qualitative description of this simplest reaction despite the fact that they are widely used to study reactions in complex systems. On the other hand, although these theories are not accurate on describing the reaction, they can be used to provide the low-level PESs for hierarchical construction of the UCCSD(T)/avqz PES with the number of UCCSD(T)/avqz energies substantially reduced.
First-principles Study of Adsorption and Dissociation of Methanol on the Pt(100) Surface
Authors: Wang Zhuo , Kan Er-jun , Yang Jin-long
Published: May 2012

Using first-principles calculations, we studied the interaction of methanol with the Pt(100) surface based on generalized gradient approximation. We found that top sites of Pt(100) surface are the favored adsorptive positions in energy, and methanol molecule interacts with the Pt surface through oxygen atoms. Moreover, we also explored the possible dissociation pathways of methanol on the Pt surface, and suggested that the products of dissociation can be controlled by the external manipulation.
Structural and Magnetic Properties of Bi(Fe1−xMnx)O3
Authors: Ding Bin-feng
Published: May 2012

Bi(Fe1−xMnx)O3 bulk ceramics with Mn concentration x up to 0.3 were prepared by rapid sintering using sol-gel derived fine powders. Structure transformation is found to depend on the Mn doping concentration by X-ray diffraction and Raman spectroscopy. Bi(Fe1−xMnx)O3 maintains the rhombohedral structure of BiFeO3 with x=0.05 and 0.1, but changes to the orthorhombic structure with x=0.3. Weak ferromagnetism is observed for Bi(Fe1−xMnx)O3 with x=0.05 and 0.1, but stronger paramagnetism is observed for Bi(Fe1−xMnx)O3 with x=0.3 indicating a magnetic phase change from antiferromagnetic to paramagnetic with the structure changing from R3c to C222. Two anomalies at 30 and 140 K are observed for Bi(Fe1−xMnx)O3 with x=0.05 and 0.1. The anomaly at 30 K is concluded to be related to the freezing of cluster spin glass from dc magnetic memory and relaxation measurements.
Preparation and Electrochemical Characteristics of Three-dimensional Manganese Oxide Micro-supercapacitor Electrode
Authors: Wen Chun-ming , Wen Zhi-yu , You Zheng , Wang Xiao-feng
Published: May 2012

In order to increase the electrode surface area and enhance the charge storage capacity, we study the micro electro mechanical system technology to fabricate three-dimensional high aspect ratio micro-electrode structure based on glass. The anodic constant potential method is employed to deposit manganese oxide as electroactive substances on the micro-electrode surface. Cyclic voltammetry and constant current charge-discharge method are both used to prepare electrode electrochemical performance testing, with a two-dimensional electrode without structure for comparison. Experimental results show that three-dimensional electrode structure can effectively enhance the charge storage capacity. At 1.0 mA/cm2 charge-discharge density, the three-dimensional electrode shows a capacitance of 17.88 mF/cm2, seven times higher than the two-dimensional electrode.
Dispersion and STM Characterization of Au-CdSe Nanohybrids on Au(111)
Authors: Gao Bo , Kuang Yan-min , Liao Yuan , Dong Zhen-chao
Published: May 2012

We report the dispersion and scanning tunneling microscopy (STM) characterization of isolated Au-CdSe nanohybrids on atomically flat Au(111) through surface modifications. The top terminal groups of spacer molecules self-assembled on the surface are found critical for locking the nanohybrids into a well-separated state. The STM results indicate that both thiol and carboxylic terminals are effective in this aspect by making strong interaction with the Au portions of the nanohybrids. An argon ion sputtering technique is also proposed to clean up organic contaminants on the surface for improved STM imaging of individual Au-CdSe nanohybrids. These observations help to enrich technical approaches to dispersing individual nanostructures on the surface and provide opportunities to explore their local electroluminescent and energy transfer properties at the nanoscale.
Effect of β-Cyclodextrin Upon the Sol-gel Transition of Methylcellulose Solutions in the Presence of Sodium Dodecyl Sulfate
Authors: Li Hua-yu , Hao Xiang , Xie Yong-jun , Yang Hai-yang , Liu He , Luo Jian-hui
Published: May 2012

The sol-gel transition temperature of methylcellulose (MC) solution in the presence of sodium dodecyl sulfate (SDS) as well as the mixtures of SDS and β-cyclodextrin (β-CD) was measured, and the effect of the two competing interactions, the hydrophobic interaction between SDS and MC and the inclusion interaction between SDS and β-CD, upon the sol-gel transition of MC solution was studied. It has been found that the inclusion interaction between SDS and β-CD is much greater than the hydrophobic interaction between SDS and MC. As a result, in the coexistence of SDS and β-CD, the sol-gel transition temperature of MC solution keeps the same value, independent of the concentration of SDS in solution on condition that the concentration of SDS is less than β-CD. Our experimental results not only suggest that the effect of SDS upon the sol-gel transition of MC solution can be screened by β-CD completely but also indicate the inclusion ratio of SDS to β-CD can be determined quantitatively by using rheological measurement. The inclusion ratio of SDS to β-CD is 1:1, which is in good agreement with the inclusion ratio of SDS to β-CD in the presence of poly(vincyl pyrrolidone) determined by the viscosity measurement but is critically different from the inclusion ratio of SDS to β-CD in the presence of the oppositely charged polyelectrolyte by using the rheological measurement, mainly due to the reason that the mechanism of the interaction between SDS and MC is critically different from the mechanism of the interaction between SDS and the oppositely charged polyelectrolyte.
Mosaic: making biological sense of complex networks
Authors: Zhang Chao , Hanspers Kristina , Kuchinsky Allan , Salomonis Nathan , Xu Dong , Pico Alexander R.
Published: May 2012

Summary: We present a Cytoscape plugin called Mosaic to support interactive network annotation, partitioning, layout and coloring based on gene ontology or other relevant annotations.

Availability: Mosaic is distributed for free under the Apache v2.0 open source license and can be downloaded via the Cytoscape plugin manager. A detailed user manual is available on the Mosaic web site (http://nrnb.org/tools/mosaic).

Contact:  apico@gladstone.ucsf.edu
Climate effects on Barents Sea ecosystem dynamics
Authors: Dalpadado Padmini , Ingvaldsen Randi B. , Stige Leif Christian , Bogstad Bjarte , Knutsen Tor , Ottersen Geir , Ellertsen Bjørnar
Published: May 2012

Dalpadado, P., Ingvaldsen, R. B., Stige, L. C., Bogstad, B., Knutsen, T., Ottersen, G., and Ellertsen, B. 2012. Climate effects on Barents Sea ecosystem dynamics. – ICES Journal of Marine Science, 69: . Effects of climate variability and change on sea temperature, currents, and water mass distribution are likely to affect the productivity and structure of high-latitude ecosystems. This paper focuses on the Barents Sea (BS), a productive Arcto–boreal shelf ecosystem sustaining several ecologically and economically important fish species. The water masses in the region are classified as Atlantic, Arctic, and mixed, each having a distinct ecological signature. The pronounced increase in temperature and a reduction in the area covered by Arctic water that has taken place during the past decade have affected the ecology of the region. An increase in biomass of lipid-rich euphausiids in recent years, possibly linked to the temperature increase, has apparently provided good feeding and growth conditions for several species, including capelin and young cod. The observed reduction in Arctic zooplankton may on the other hand have negative implications for polar cod and other zooplankton predators linked to the Arctic foodweb. Despite these changes, the BS at present seems to maintain relatively stable levels of boreal zooplankton biomass and production, with no significant changes in the abundances of Calanus finmarchicus or the episodic immigrant C. helgolandicus.
SMALL ACIDIC PROTEIN1 Acts with RUB Modification Components, the COP9 Signalosome, and AXR1 to Regulate Growth and Development of Arabidopsis
Authors: Nakasone Akari , Fujiwara Masayuki , Fukao Yoichiro , Biswas Kamal Kanti , Rahman Abidur , Kawai-Yamada Maki , Narumi Issay , Uchimiya Hirofumi , Oono Yutaka
Published: May 2012

Previously, a dysfunction of the SMALL ACIDIC PROTEIN1 (SMAP1) gene was identified as the cause of the anti-auxin resistant1 (aar1) mutant of Arabidopsis (Arabidopsis thaliana). SMAP1 is involved in the response pathway of synthetic auxin, 2,4-dichlorophenoxyacetic acid, and functions upstream of the auxin/indole-3-acetic acid protein degradation step in auxin signaling. However, the exact mechanism by which SMAP1 functions in auxin signaling remains unknown. Here, we demonstrate that SMAP1 is required for normal plant growth and development and the root response to indole-3-acetic acid or methyl jasmonate in the auxin resistant1 (axr1) mutation background. Deletion analysis and green fluorescent protein/glutathione S-transferase pull-down assays showed that SMAP1 physically interacts with the CONSTITUTIVE PHOTOMORPHOGENIC9 SIGNALOSOME (CSN) via the SMAP1 F/D region. The extremely dwarf phenotype of the aar1-1 csn5a-1 double mutant confirms the functional role of SMAP1 in plant growth and development under limiting CSN functionality. Our findings suggest that SMAP1 is involved in the auxin response and possibly in other cullin-RING ubiquitin ligase-regulated signaling processes via its interaction with components associated with RELATED TO UBIQUITIN modification.
Chloroplast RH3 DEAD Box RNA Helicases in Maize and Arabidopsis Function in Splicing of Specific Group II Introns and Affect Chloroplast Ribosome Biogenesis
Authors: Asakura Yukari , Galarneau Erin , Watkins Kenneth P. , Barkan Alice , van Wijk Klaas J.
Published: May 2012

Chloroplasts in angiosperms contain at least seven nucleus-encoded members of the DEAD box RNA helicase family. Phylogenetic analysis shows that five of these plastid members (RH22, -39, -47, -50, and -58) form a single clade and that RH3 forms a clade with two mitochondrial RH proteins (PMH1 and -2) functioning in intron splicing. The function of chloroplast RH3 in maize (Zea mays; ZmRH3) and Arabidopsis (Arabidopsis thaliana; AtRH3) was determined. ZmRH3 and AtRH3 are both under strong developmental control, and ZmRH3 abundance sharply peaked in the sink-source transition zone of developing maize leaves, coincident with the plastid biogenesis machinery. ZmRH3 coimmunoprecipitated with a specific set of plastid RNAs, including several group II introns, as well as pre23S and 23S ribosomal RNA (rRNA), but not 16S rRNA. Furthermore, ZmRH3 associated with 50S preribosome particles as well as nucleoids. AtRH3 null mutants are embryo lethal, whereas a weak allele (rh3-4) results in pale-green seedlings with defects in splicing of several group II introns and rRNA maturation as well as reduced levels of assembled ribosomes. These results provide strong evidence that RH3 functions in the splicing of group II introns and possibly also contributes to the assembly of the 50S ribosomal particle. Previously, we observed 5- to 10-fold up-regulation of AtRH3 in plastid Caseinolytic protease mutants. The results shown here indicate that AtRH3 up-regulation was not a direct consequence of reduced proteolysis but constituted a compensatory response at both RH3 transcript and protein levels to impaired chloroplast biogenesis; this response demonstrates that cross talk between the chloroplast and the nucleus is used to regulate RH3 levels.
The structures of three Hg2X4L2macrocycles {X= Cl, Br and I, andL= 1,2-bis[4-(pyridin-3-yl)phenoxy]ethane} assembled from ether-bridged dipyridyl ligands
Authors: Wu Dan , Qin Na , Liu Qi-Kui , Ma Jian-Ping , Dong Yu-Bin
Published: May 2012

The new ether-bridged dipyridyl ligand 1,2-bis[4-(pyridin-3-yl)phenoxy]ethane (L) has been used to synthesize three isostructural centrosymmetric binuclear HgIImacrocycles, namely bis{μ-1,2-bis[4-(pyridin-3-yl)phenoxy]ethane-κ2N:N′}bis[dichloridomercury(II)], [Hg2Cl4(C24H20N2O2)2], and the bromido, [Hg2Br4(C24H20N2O2)2], and iodido, [Hg2I4(C24H20N2O2)2], analogues. The Hg atoms adopt a highly distorted tetrahedral coordination environment consisting of two halides and two pyridineN-donor atoms from two bridging ligands. In the solid state, the macrocycles form two-dimensional sheets in thebcplane through noncovalent Hg...XandX...X(X= Cl, Br and I) interactions.
N-[4-(4-Bromophenyl)thiazol-2-yl]-4-(piperidin-1-yl)butanamide
Authors: Ghabbour Hazem A. , Kadi Adnan A. , El-Subbagh Hussein I. , Chia Tze Shyang , Fun Hoong-Kun
Published: May 2012

In the title compound, C18H22BrN3OS, the piperidine ring adopts a chair conformation. The mean plane of the thiazole ring forms dihedral angles of 23.97 (10) and 75.82 (10)° with the mean planes of its adjacent benzene and piperidine rings, respectively. An intramolecular N—H...N hydrogen bond generates an S(7) ring motif in the molecule. In the crystal, no significant intermoelcular hydrogen bonds are observed, but a weak π–π interaction with a centroid–centroid distance of 3.8855 (13) Å occurs.
4-Chloro-2-[(4-chlorobenzylidene)amino]phenol
Authors: Efil Kürşat , Şen Fatih , Bekdemir Yunus , Büyükgüngör Orhan
Published: May 2012

In the title Schiff base compound, C13H9Cl2NO, the molecule displays an E conformation about the imine C=N double bond, with a dihedral angle of 8.09 (11)° between the two benzene rings. In the crystal, molecules are linked by a single O—H...O hydrogen bond, giving one-dimensional chains which extend along (100).
N-(4-Bromobenzylidene)naphthalen-1-amine
Authors: Zhu Ruitao , Ren Yuehong , Zhang Yuewen
Published: May 2012

The title molecule, C17H12BrN, is in a E conformation with respect to the C=N bond. The dihedral angle between the naphthalene ring system and the benzene ring is 53.26 (3)°.
Methyl 2-[4-(4-chlorobenzoyl)phenoxy]-2-methylpropanoate
Authors: Zou Baohua , Fang Zheng , Zhong Hui , Guo Kai , Wei Ping
Published: May 2012

In the title compound, C18H17ClO4, the dihedral angle between the mean planes of the benzene rings is 53.4 (1)°. Weak intermolecular C—H...O interactions are observed.
Triaqua-1κO,2κ2
O-bis(2,2′-bipyridine)-1κ2
N,N′;2κ2
N,N′-chlorido-1κCl-μ-terephthalato-1:2κ2
O
1:O
4-dicopper(II) nitrate monohydrate
Authors: Liu Yang , Feng Yong-Lan , Kuang Dai-Zhi
Published: May 2012

In the binuclear title compound, [Cu2(C8H4O4)Cl(C10H8N2)2(H2O)3]NO3·H2O, the two crystallographically independent CuII ions have similar coordination environments. One of the CuII ions has a square-pyramidal arrangement, which is defined by a water molecule occupying the apical position, with the equatorial ligators consisting of two N atoms from a 2,2′-bipyridine molecule, one carboxylate O atom from a terephthalate ligand and one O atom from a water molecule. The other CuII ion has a similar coordination environment, except that the apical position is occupied by a chloride ligand instead of a water molecule. An O—H...O and O—H...Cl hydrogen-bonded three-dimensional network is formed between the components.
2-Phenyl-N′-(2-phenylacetyl)acetohydrazide
Authors: Abdel-Aziz Hatem A. , Quah Ching Kheng , Fun Hoong-Kun
Published: May 2012

In the title compound, C16H16N2O2, the N′-acetylacetohydrazide group is approximately planar (r.m.s. deviation = 0.018 Å for the eight non-H atoms) and makes dihedral angles of 81.92 (6) and 65.19 (6)° with the terminal phenyl rings. The phenyl rings form a dihedral angle of 62.60 (7)°. In the crystal, molecules are linked into sheets lying parallel to (001) by N—H...O and C—H...O hydrogen bonds. One O atom accepts one N—H...O and one C—H...O hydrogen bond and the other O atom accepts one N—H...O and two C—H...O hydrogen bonds. The N—H...O hydrogen bonds lead to R
2
2(8) loops and the C—H...O hydrogen bonds generate R
2
1(6) loops.
2-Hydroxypyridinium p-toluenesulfonate
Authors: Jin Yu
Published: May 2012

In the title molecular salt, C5H6NO+·C7H7O3S−, the cations and anions are connected by N—H...O and O—H...O hydrogen bonds, forming [100] chains.
6-(4-Bromophenyl)-3-methyl-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazine
Authors: Fun Hoong-Kun , Quah Ching Kheng , Abdel-Aziz Hatem A. , Attia Mohamed I.
Published: May 2012

In the title compound, C11H9BrN4S, the 1,2,4-triazole ring is essentially planar (r.m.s. deviation = 0.020 Å) and makes a dihedral angle of 29.1 (5)° with the bromobenzene ring. The 3,6-dihydro-1,3,4-thiadiazine ring adopts a twist-boat conformation. In the crystal, molecules are linked by C—H...N interactions into sheets lying parallel to the (010) plane. The same N atom accepts two such hydrogen bonds.
Ethyl 4-anilino-3-nitrobenzoate
Authors: Yoon Yeong Keng , Manogaran Elumalai , Ali Mohamed Ashraf , Arshad Suhana , Razak Ibrahim Abdul
Published: May 2012

In the title compound, C15H14N2O4, the dihedral angle between the benzene and phenyl rings is 73.20 (6)°. An intramolecular N—H...O hydrogen bond forms an S(6) ring motif. In the crystal, molecules are linked by N—H...O and C—H...O hydrogen bonds into a layer parallel to the bc plane.
Methyl (R)-2-(2-chlorophenyl)-2-(3-nitrophenylsulfonyloxy)acetate
Authors: Li Ying-Hua , Xu Hong-Wu , Zhang Liu-Xue
Published: May 2012

The reaction between methyl (R)-2-(2-chlorophenyl)-2-hydroxyacetate and 3-nitrobenzenesulfonyl chloride gave the title compound, C15H12ClNO7S, which is a promising intermediate for the synthesis of Clopidrogel, an antiplatelet drug used in the prevention of strokes and heart attacks. In the crystal, molecules are linked through C—H...O interactions, and there is also a short Cl...O contact present [Cl...O = 3.018 (2) Å].
Bis(3-methylpiperidinium) naphthalene-1,5-disulfonate
Authors: Xu Qian
Published: May 2012

The asymmetric unit of the title compound, 2C6H14N+·C10H6O6S2
2−, contains one 3-methylpiperidinium cation and one-half of the centrosymmetric naphthalene-1,5-disulfonate anion. In the crystal, anions and cations are linked through N—H...O hydrogen bonds into layers parallel to (101).
N-(Quinolin-8-yl)quinoline-2-carboxamide
Authors: Li Yanfeng , Zhou Hongbo , Shen Xiaoping
Published: May 2012

In the title compound, C19H13N3O, the dihedral angle between the two quinoline systems is 11.54 (3)°. The molecular conformation is stabilized by intramolecular N—H...N and C—H...O hydrogen bonds, with N—H...N being bifurcated towards the two N atoms of the two quinoline rings. In the crystal, there are weak intermolecular π–π interactions present involving the quinoline rings [centroid–centroid distance 3.7351 (14) Å].
Sodium pentapotassium pentanickel tetra(diphosphate), NaK5Ni5(P2O7)4
Authors: Moutataouia Meryem , Lamire Mohammed , Saadi Mohamed , El Ammari Lahcen
Published: May 2012

The structure of the title compound, NaK5Ni5(P2O7)4, is characterized by the presence of two crystallographically independent P2O7 groups with different conformations. The conformation of the first P2O7 group is eclipsed, whereas that of the second is staggered. All atoms are in general positions except for two nickel and one potassium ions which lie on symmetry centers. Moreover, the structure exhibits disorder of the cationic sites with one general position fully occupied equally by Na+ and Ni2+ cations. This mixed site is surrounded by five O atoms forming a square-based pyramid. The crystal structure consists of edge-sharing [NiO6] octahedra forming infinite zigzag chains [Ni3O14] running parallel to [100]. Adjacent chains are connected through apices to P2O7 groups and to another [NiO6] or to a [KO6] octahedron. The resulting three-dimensional framework presents intersecting tunnels running along the [010] and [001] directions in which the seven- and nine-coordinated potassium cations are located. The crystal structure of this new phosphate represents a new structural type.
Bis{N
2,N
6-bis[(pyridin-3-yl)methyl]pyridine-2,6-dicarboxamide-κN}bis(methanol-κO)bis(thiocyanato-κN)cobalt(II)
Authors: Yang Guang-Rui , Ren Juan , Li Guo-Ting
Published: May 2012

In the title compound, [Co(NCS)2(C19H17N5O2)2(CH3OH)2], the CoII atom lies on an inversion center and is coordinated by two isothiocyanate N atoms, two O atoms of methanol molecules and two pyridine N atoms in a slightly distorted octahedral environment. Intermolecular O—H...O and N—H...N hydrogen bonds join the complex molecules into layers parallel to the bc plane.
7-(6-Bromohexyloxy)-4-methyl-2H-chromen-2-one
Authors: Zhang Hui-Zhen , Li Qing-Xia , Yin Ben-Tao , Zhou Cheng-He
Published: May 2012

In the title molecule, C16H19BrO3, all non-H atoms apart from the Br atom are approximately coplanar, with a maximum deviation of 0.242 (4) Å. The C—C—C—Br torsion angle is 66.5 (4)°.
2-(2-Bromophenyl)acetic acid
Authors: Kant Rajni , Kapoor Kamini , Narayana B.
Published: May 2012

In the title molecule, C8H7BrO2, the carboxyl group is twisted by 76.2 (3)° from the benzene ring plane. In the crystal, molecules are linked into inversion dimers through pairs of O—H...O hydrogen bonds. The dimers are further linked into layers parallel to the bc plane by weak C—H...O hydrogen bonds.
4-Cyanopyridinium nitrate
Authors: Zheng Wen-Ni
Published: May 2012

The title compound, C6H5N2
+·NO3
−, is a proton-transfer compound between 4-cyanopyridine and nitric acid. In the asymmetric unit, the components are linked by a strong N—H...O hydrogen bond. In the crystal, molecules are linked into a C(6) chain along [010] by C—H...O interactions.
rac-2-(2-Chloro-6-methylquinolin-3-yl)-2,3-dihydroquinolin-4(1H)-one
Authors: Bouraiou Abdelmalek , Bouacida Sofiane , Bertrand Carboni , Roisnel Thierry , Belfaitah Ali
Published: May 2012

In the title compound, C19H15ClN2O, the quinoline ring forms a dihedral angle of 43.24 (1)° with the benzene ring of the dihydroquinolinyl system. In the crystal, molecules are linked through a single weak C—H...O hydrogen bond, forming ribbons which extend along (100), giving alternating zigzag molecular layers which stack down the b-axis direction.
(E)-3-Dimethylamino-1-(2,5-dimethylthiophen-3-yl)prop-2-en-1-one
Authors: Ghorab Mostafa M. , Al-Said Mansour S. , Ghabbour Hazem A. , Chia Tze Shyang , Fun Hoong-Kun
Published: May 2012

In the title compound, C11H15NOS, the 3-(dimethylamino)prop-2-en-1-one unit is approximately planar [maximum deviation = 0.0975 (14) Å] and its mean plane of seven non-H atoms makes a dihedral angle of 6.96 (10)° with the thiophene ring. In the crystal, molecules are linked by pairs of C—H...O hydrogen bonds into inversion dimers with R
2
2(14) ring motifs. The dimers are stacked along the c axis through C—H...π interactions. The two methyl groups, attached to the thiophene ring and the amino N atom, are each disordered over two orientations, with site-occupancy ratios of 0.59 (4):0.41 (4) and 0.74 (4):0.26 (4), respectively.
7-Bromo-9-(2-hydroxy-4,4-dimethyl-6-oxocyclohex-1-en-1-yl)-3,3-dimethyl-2,3,4,9-tetrahydro-1H-xanthen-1-one
Authors: Mohamed Shaaban K. , Akkurt Mehmet , Abdelhamid Antar A. , Fanwick Phillip E. , Potgeiter Herman
Published: May 2012

In the xanthene ring system of the title compound, C23H25BrO4, the 4H-pyran ring is almost planar [maximum deviation = 0.040 (3) Å] and the cyclohexene ring adopts a sofa conformation. The cyclohexene ring attached to the xanthene system is puckered [Q
T = 0.427 (3) Å, θ = 55.0 (4) ° and φ = 164.4 (6) °]. In the crystal, molecules are linked to each other by O—H...O and C—H...O hydrogen bonds.
4,4′-Bipyridine–terephthalic acid (1/1)
Authors: Koteswara Rao Vandavasi , Zeller Matthias , Lovelace-Cameron Sherri R.
Published: May 2012

The asymmetric unit of the title compound, C10H8N2·C8H6O4, consists of one half-molecule of each moiety, 4,4′-bipyridine (bpy) and terephthalic acid (bdc), both being located on crystallographic inversion centers. They are linked together via strong intermolecular O—H...N hydrogen bonds, forming infinite chains propagating along [1-21]. The chains are further connected through C—H...O interactions giving sheets in (012). The sheets are linked via π–π interactions between the bpy rings and the bdc–bpy rings [centroid–centroid distances = 3.690 (2) and 3.869 (2) Å], resulting in the formation of a three-dimensional supramolecular layer-like structure.
Genomic copy‐number alterations of MYC and FHIT genes are associated with survival in esophageal squamous‐cell carcinoma
Authors: Miyawaki Yutaka , Kawachi Hiroshi , Ooi Akishi , Eishi Yoshinobu , Kawano Tatsuyuki , Inazawa Johji , Imoto Issei
Published: May 2012

Esophageal squamous‐cell carcinoma (ESCC) is one of the most common cancers and is associated with a poor prognosis. Studies are warranted on the clinical relevance of its genomic copy‐number alterations (CNA) as prognosticators for ESCC. In the present study, we first screened recurrent CNA by array‐based comparative genomic hybridization using an in‐house focused bacterial artificial chromosome‐based array for 108 loci in 45 ESCC specimens. We detected 14 regions showing recurrent (>20%) CNA (4 losses and 10 gains) by array‐based comparative genomic hybridization in the first cohort. Among them, loss of 3p14.2 and gain of 8q24.21 for the FHIT and MYC genes, respectively, and the accumulation of those two CNA (higher FM‐CNA scores) were significantly associated with a worse overall survival (OS) in the first cohort (P = 0.0273, P = 0.0356 and P = 0.0089, respectively). In the independent validation cohort of 92 resected ESCC cases, loss of FHIT, gain of MYC and higher FM‐CNA scores determined by a quantitative genomic PCR‐based copy‐number analysis were associated with a worse OS (P = 0.0011, P = 0.0104 and P = 0.0008, respectively) and disease‐free survival (P = 0.0038, P = 0.0132 and P = 0.0021, respectively). In addition, the Cox model showed the presence of either CNA to be an independent prognosticator for OS and disease‐free survival in the validation cohort (P = 0.0120 and P = 0.0255, respectively). These results suggest that CNA of MYC and FHIT are poor prognostic markers, and risk stratification based on the copy‐number status of those genes is useful to select the optimal treatment strategy in resected ESCC patients. (Cancer Sci, doi: 10.1111/j.1349‐7006.2012.02329.x, 2012)
Prospective memory and future event simulation in individuals with alcohol dependence
Authors: Griffiths Alison , Hill Robert , Morgan Celia , Rendell Peter G. , Karimi Khashayar , Wanagaratne Shamil , Curran H. Valerie
Published: May 2012

Aim

To assess objectively prospective memory (PM) performance of individuals with alcohol dependence and determine whether the use of an imagery technique at the point of encoding can enhance their performance.

Design

An independent group design was used to compare individuals with alcohol dependence with social drinkers.

Setting

One UK residential substance misuse service.

Participants

Twenty‐four abstinent ‘individuals with alcohol dependence’ and 24 social drinkers matched on age, gender and years of education.

Measurements

The virtual week (VW); story recall; a category fluency task; trail‐making test (TMT); a single digit cancellation task (SDCT); spot‐the‐word; State–Trait Anxiety Inventory (STAI); Beck Depression Inventory (BDI‐II); and the Severity of Alcohol Dependence Questionnaire (SAD‐Q)

Findings

Event‐based PM task performance of individuals with alcohol dependence was associated strongly with indices of alcohol usage (P < 0.001), and was impaired significantly compared to that of social drinkers (P < 0.001). Imagining improved social drinkers' time‐based PM but not that of individuals with alcohol dependence.

Conclusions

Individuals with alcohol dependence may experience prospective memory deficits which may be due to difficulties with effective strategy application.
Amino acids in Tobamovirus coat protein controlling pepper L1a gene‐mediated resistance
Authors: MIZUMOTO HIROYUKI , NAKAMURA IKUMI , SHIMOMOTO YOSHIFUMI , SAWADA HIROMASA , TOMITA REIKO , SEKINE KEN‐TARO , KIBA AKINORI , NISHIGUCHI MASAMICHI , KOBAYASHI KAPPEI , HIKICHI YASUFUMI
Published: May 2012

In pepper plants (genus Capsicum), the resistance against Tobamovirus spp. is conferred by L gene alleles. The recently identified L variant L1a can recognize coat proteins (CPs) of Tobacco mild green mosaic virus Japanese strain (TMGMV‐J) and Paprika mild mottle virus Japanese strain (PaMMV‐J), but not of Pepper mild mottle virus (PMMoV), as the elicitor to induce resistance at 24 °C. Interestingly, L1a gene‐mediated resistance against TMGMV‐J, but not PaMMV‐J, is retained at 30 °C. This observation led us to speculate that L1a can discriminate between CPs of TMGMV‐J and PaMMV‐J. In this study, we aimed to determine the region(s) in CP by which L1a distinguishes TMGMV‐J from PaMMV‐J. By using chimeric CPs consisting of TMGMV‐J and PaMMV‐J, we found that the chimeric TMGMV‐J CP, whose residues in the β‐sheet domain were replaced by those of PaMMV‐J, lost its ability to induce L1a gene‐mediated resistance at 30 °C. In contrast, the chimeric PaMMV‐J CP with the β‐sheet domain replaced by TMGMV‐J CP was able to induce L1a gene‐mediated resistance at 30 °C. Furthermore, viral particles were not detected in the leaves inoculated with either chimeric virus. These observations indicated that the amino acids within the β‐sheet domain were involved in both the induction of L1a gene‐mediated resistance and virion formation. Further analyses using chimeric CPs of TMGMV‐J and PMMoV indicated that amino acids within the β‐sheet domain alone were not sufficient for the induction of L1a gene‐mediated resistance by TMGMV‐J CP. These results suggest that multiple regions in Tobamovirus CP are implicated in the induction of L1a gene‐mediated resistance.