bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mineralogy of Dickite and Nacrite From Northern Taiwan
Authors: Chen Pei Yuan , Wang Ming Kuang , Yang Deng Shiu 
Published: September 2006

AbstractNacrite and dickite are found in two localities in northern Taiwan. One, containing nacrite and dickite, is associated with a gold-enargite deposit as a vug-filling clay in the Chinkushih (CKS) mine district near the northern coast. The other is the occurrence of dickite in the interstices of a Miocene coarse-grained quartzose sandstone in the Nanshihchiao (NSC) area, near Taipei city. X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron microscope (SEM), and petrographic examinations were used to characterize the mineralogical features. Nacrite most often takes the unusual form of rhombic platelets, and dickite is commonly elongated in habit with the shapes possibly related to their origin. Based on geological evidence, we believe that both nacrite and dickite are of hydrothermal origin. In the CKS area, the formation of nacrite and dickite is related to the hypogene gold-enargite mineralization. In contrast, the transformation of dickite in the NSC area is due to the influence of the raised temperatures of sandstone formation, resulting from volcanic activity during the Kungkuan stage after the deposition of the sandstone.
Neumatizing the Sequence: Special Performances of Sequences in the Central Middle Ages
Authors: KRUCKENBERG LORI 
Published: September 2006

Abstract
In his liturgical commentary Rationale divinorum officiorum, the thirteenthcentury writer Guillaume Durand describes a special, “antique” way of singing sequences called “neumatizing” (“neumatizare”). According to Durand, a sequence could be neumatized either by singing certain phrases melismatically or by vocalizing the entire sequence without words. The chief focus of this investigation is the identification of which sequences were still being neumatized after the decline of that practice around 1100, where and at which feasts they were sung, and why. The evidence suggests that neumatizing was especially cultivated in northern France during the twelfth and thirteenth centuries, especially in the cathedral towns of Rouen, Laon, Cambrai, and Amiens, as well as at various religious institutions in Metz, Andenne, Chichester, and Bamberg. The liturgical period of Advent, Christmas Eve, the Feast of John the Evangelist, and masses celebrating patron saints were the most typical liturgical occasions where neumatizing took place. The rationales for the singing practice appear to have been manifold, ranging from the practical and mundane to the spiritual and sacred. Motives for neumatizing include improving preexisting structures for purposes of fulfilling expectations about genre; using musical responses to highlight poetic topoi; lending solemnity and symbolic meaning to important liturgical feasts; and honoring ancient traditions while resisting some of the newer trends found with late examples of the genre.
Metathesis of 1‐Octene in Ionic Liquids and Other Solvents: Effects of Substrate Solubility, Solvent Polarity and Impurities
Authors: Stark Annegret , Ajam Mariam , Green Mike , Raubenheimer Helgard G. , Ranwell Alta , Ondruschka Bernd 
Published: September 2006

AbstractWith the self‐metathesis of 1‐octene to 7‐tetradecene catalyzed by Grubbs 1st generation [benzylidene‐bis(tricyclohexylphosphine)dichlororuthenium, (1)] precursor at low concentrations (0.02 mol %) as basis, the effects of the solubility of the substrate in ionic liquids, the solvent polarity, as well as the influence of various impurities stemming from the preparation of ionic liquids have been investigated. The solubility of the substrate in the ionic liquid has little effect on the conversion, and the reaction is not mass‐transfer limited. While a higher polarity of an organic solvent increases the rate, it is independent of the polarity excerted by the cation of an ionic liquid. Of paramount importance for reproducible results is the purity of ionic liquids. An extensive study shows that catalyst deactivation by impurities increases in the order of water<halide<1‐methylimidazole. In the presence of water or 1‐methylimidazole impurities, the Grubbs‐Hoveyda precursor (3) is superior to both the 1st (1) and 2nd (2) generation Grubbs complexes. Under impurity‐free conditions or in the presence of chloride, the performance of 2 is equivalent to that of 3.
Automated detection of tunneling nanotubes in 3D images
Authors: Hodneland Erlend , Lundervold Arvid , Gurke Steffen , Tai Xue‐Cheng , Rustom Amin , Gerdes Hans‐Hermann 
Published: September 2006

AbstractBackground:This paper presents an automated method for the identification of thin membrane tubes in 3D fluorescence images. These tubes, referred to as tunneling nanotubes (TNTs), are newly discovered intercellular structures that connect living cells through a membrane continuity. TNTs are 50–200 nm in diameter, crossing from one cell to another at their nearest distance. In microscopic images, they are seen as straight lines. It now emerges that the TNTs represent the underlying structure of a new type of cell‐to‐cell communication.Methods:Our approach for the identification of TNTs is based on a combination of biological cell markers and known image processing techniques. Watershed segmentation and edge detectors are used to find cell borders, TNTs, and image artifacts. Mathematical morphology is employed at several stages of the processing chain. Two image channels are used for the calculations to improve classification of watershed regions into cells and background. One image channel displays cell borders and TNTs, the second is used for cell classification and displays the cytoplasmic compartments of the cells. The method for cell segmentation is 3D, and the TNT detection incorporates 3D information using various 2D projections.Results:The TNT‐ and cell‐detection were applied to numerous 3D stacks of images. A success rate of 67% was obtained compared with manual identification of the TNTs. The digitalized results were used to achieve statistical information of selected properties of TNTs.Conclusion:To further explore these structures, automated detection and quantification is desirable. Consequently, this automated recognition tool will be useful in biological studies on cell‐to‐cell communication where TNT quantification is essential. © 2006 International Society for Analytical Cytology
A modern biomaterial for adhesion prevention
Authors: diZerega Gere S. , Cortese Stephanie , Rodgers Kathleen E. , Block Kathleen M. , Falcone Samuel J. , Juarez Thomas G. , Berg Richard 
Published: September 2006

AbstractA biomaterial composed of carboxymethylcellulose, poly(ethylene oxide), and calcium can be prepared in a variety of ways to reduce fibrin deposition and adhesion formation. This biomaterial platform can be formulated into a flowable gel with tissue adherence appropriate for use in minimally invasive surgery. The device remains at the site of placement even in gravitationally dependent areas. A peridural formulation was shown in preclinical studies to be safe and effective in reducing adhesions to dura following spinal surgery. A peritoneal formulation used on pelvic organs following peritoneal cavity surgery was also shown to be safe and effective. A clinical feasibility study showed that patients with severe back pain and lower extremity weakness treated with the peridural formulation, applied over their nerve roots following laminectomy or laminotomy, experienced significantly reduced symptoms when compared with surgery‐only controls. The peritoneal formulation was shown in two multicenter feasibility studies of women undergoing pelvic surgery to significantly reduce adhesion formation when compared with surgery‐only controls. Confirmation of the feasibility studies awaits results from pivotal clinical trials. These formulations were safe, effective, and easy to use. This biomaterial provided a benefit to patients undergoing surgery where postsurgical adhesion formation is a concern. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Ganglionary mechanisms of spasticity and ileus in cerebral hemorrhage: an experimental study
Authors: Aydin Mehmet Dumlu , Erdogan Ali Riza , Cevli Salih Cenap , Gundogdu Cemal , Dane Senol , Diyarbakirli Semih 
Published: September 2006

AbstractObjectiveThe effects of retrograde neuronal death is well determined in dorsal root ganglia (DRG) after peripheral nerve injury, but the effects of intracerebral hemorrhage on the DRG has not been well known. In this study, it was investigated if hemorrhagic lesions of sensory–motor cortex cause neurodegeneration on DRG.Materials and MethodsThis study was conducted on 23 male hybrid rabbits. Three of 23 animals were examined as control. Left parietal burr‐hole surgery was applied to remaining 20 animals and autolog blood of 0.25 ml injected into left sensory–motor region under general anesthesia. All rabbits were followed‐up for two months and sacrificed. L5 DRG's were observed histopathologically. The results were analyzed with Mann–Whitney U‐test.ResultsRight spastic hemiplegia developed only in 16 operated animals and 10 of them were developed ileus. The number of degenerated neurons in DRG was higher in the plegic side than in the non‐plegic side (p < 0.001). But, the difference between the non‐plegic side of the study group and control group did not meaningful (p > 0.05).ConclusionIntracerebral hemorrhages affecting the sensory–motor cortex may result in neurodegeneration in DRG. Sensitive reflex arches of striated muscles and bowels may be disturbed due to DRG degeneration and results in spasticity and/or ileus.
Pathogen-Induced Arabidopsis WRKY7 Is a Transcriptional Repressor and Enhances Plant Susceptibility to Pseudomonas syringae
Authors: Kim Kang-Chang , Fan Baofang , Chen Zhixiang 
Published: September 2006

Abstract
The Arabidopsis (Arabidopsis thaliana) WRKY7 gene is induced by pathogen infection and salicylic acid (SA) treatment and may therefore play a role in plant defense responses. Here, we show that WRKY7 is localized in the nucleus, recognizes DNA molecules with the W-box (TTGAC) elements, and functions as a transcriptional repressor in plant cells. To study its biological functions directly, we have characterized both loss-of-function T-DNA insertion and RNAi mutants and gain-of-function transgenic overexpression plants for WRKY7 in Arabidopsis. The T-DNA insertion and RNAi mutant plants displayed enhanced resistance to a virulent strain of the bacterial pathogen Pseudomonas syringae as measured by significant decrease in both bacterial growth and symptom development as compared to those in wild-type plants. The enhanced resistance in the loss-of-function mutants was associated with increased induction of SA-regulated Pathogenesis-Related 1 (PR1) by the bacterial pathogen. Transgenic plants that constitutively overexpress WRKY7 have altered leaf growth and morphology strikingly similar to those observed in the previously isolated eds8 mutant plants. Like eds8 mutant plants, WRKY7-overexpressing plants supported more growth of P. syringae and developed more severe disease symptoms than wild-type plants. The enhanced susceptibility of both the WRKY7-overexpressing plants and the eds8 mutant correlated with reduced expression of defense-related genes, including PR1, but significantly increased accumulation of SA after pathogen infection, probably due to reduced negative feedback of SA synthesis. Thus, pathogen-induced WRKY7 transcription factor play a negative role in defense responses to P. syringae.
Consistency of Polyamine Profiles and Expression of Arginine Decarboxylase in Mitosis during Zygotic Embryogenesis of Scots Pine
Authors: Vuosku Jaana , Jokela Anne , Läärä Esa , Sääskilahti Mira , Muilu Riina , Sutela Suvi , Altabella Teresa , Sarjala Tytti , Häggman Hely 
Published: September 2006

Abstract
In this study, we show that both arginine decarboxylase (ADC) protein and mRNA transcript are present at different phases of mitosis in Scots pine (Pinus sylvestris) zygotic embryogenesis. We also examined the consistency of polyamine (PA) profiles with the effective temperature sum, the latter indicating the developmental stage of the embryos. PA metabolism was analyzed by fitting statistical regression models to the data of free and soluble conjugated PAs, to the enzyme activities of ADC and ornithine decarboxylase (ODC), as well as to the gene expression of ADC. According to the fitted models, PAs typically had the tendency to increase at the early stages but decrease at the late stages of embryogenesis. Only the free putrescine fraction remained stable during embryo development. The PA biosynthesis strongly preferred the ADC pathway. Both ADC gene expression and ADC enzyme activity were substantially higher than putative ODC gene expression or ODC enzyme activity, respectively. ADC gene expression and enzyme activity increased during embryogenesis, which suggests the involvement of transcriptional regulation in the expression of ADC. Both ADC mRNA and ADC protein localized in dividing cells of embryo meristems and more specifically within the mitotic spindle apparatus and close to the chromosomes, respectively. The results suggest the essential role of ADC in the mitosis of plant cells.
Isolation ofmtpimProvesTnt1a Useful Reverse Genetics Tool inMedicago truncatulaand Uncovers New Aspects ofAP1-Like Functions in Legumes
Authors: Benlloch Reyes , d'Erfurth Isabelle , Ferrandiz Cristina , Cosson Viviane , Beltrán José Pío , Cañas Luis Antonio , Kondorosi Adam , Madueño Francisco , Ratet Pascal 
Published: September 2006

AbstractComparative studies help shed light on how the huge diversity in plant forms found in nature has been produced. We use legume species to study developmental differences in inflorescence architecture and flower ontogeny with classical models such as Arabidopsis thaliana or Antirrhinum majus. Whereas genetic control of these processes has been analyzed mostly in pea (Pisum sativum), Medicago truncatula is emerging as a promising alternative system for these studies due to the availability of a range of genetic tools. To assess the use of the retrotransposon Tnt1 for reverse genetics in M. truncatula, we screened a small Tnt1-mutagenized population using degenerate primers for MADS-box genes, known controllers of plant development. We describe here the characterization of mtpim, a new mutant caused by the insertion of Tnt1 in a homolog to the PROLIFERATING INFLORESCENCE MERISTEM (PIM)/APETALA1 (AP1)/SQUAMOSA genes. mtpim shows flower-to-inflorescence conversion and altered flowers with sepals transformed into leaves, indicating that MtPIM controls floral meristem identity and flower development. Although more extreme, this phenotype resembles the pea pim mutants, supporting the idea that M. truncatula could be used to complement analysis of reproductive development already initiated in pea. In fact, our study reveals aspects not shown by analysis of pea mutants: that the mutation in the AP1 homolog interferes with the specification of floral organs from common primordia and causes conversion of sepals into leaves, in addition to true conversion of flowers into inflorescences. The isolation of mtpim represents a proof of concept demonstrating that Tnt1 populations can be efficiently used in reverse genetics screenings in M. truncatula.
Identification of Drought Tolerance Determinants by Genetic Analysis of Root Response to Drought Stress and Abscisic Acid
Authors: Xiong Liming , Wang Rui-Gang , Mao Guohong , Koczan Jessica M. 
Published: September 2006

AbstractDrought stress is a common adverse environmental condition that seriously affects crop productivity worldwide. Due to the complexity of drought as a stress signal, deciphering drought tolerance mechanisms has remained a major challenge to plant biologists. To develop new approaches to study plant drought tolerance, we searched for phenotypes conferred by drought stress and identified the inhibition of lateral root development by drought stress as an adaptive response to the stress. This drought response is partly mediated by the phytohormone abscisic acid. Genetic screens using Arabidopsis (Arabidopsis thaliana) were devised, and drought inhibition of lateral root growth (dig) mutants with altered responses to drought or abscisic acid in lateral root development were isolated. Characterization of these dig mutants revealed that they also exhibit altered drought stress tolerance, indicating that this root response to drought stress is intimately linked to drought adaptation of the entire plant and can be used as a trait to access the elusive drought tolerance machinery. Our study also revealed that multiple mechanisms coexist and together contribute to whole-plant drought tolerance.
Building Up of the Plastid Transcriptional Machinery during Germination and Early Plant Development
Authors: Demarsy Emilie , Courtois Florence , Azevedo Jacinthe , Buhot Laurence , Lerbs-Mache Silva 
Published: September 2006

Abstract
The plastid genome is transcribed by three different RNA polymerases, one is called plastid-encoded RNA polymerase (PEP) and two are called nucleus-encoded RNA polymerases (NEPs). PEP transcribes preferentially photosynthesis-related genes in mature chloroplasts while NEP transcribes preferentially housekeeping genes during early phases of plant development, and it was generally thought that during plastid differentiation the building up of the NEP transcription system precedes the building up of the PEP transcription system. We have now analyzed in detail the establishment of the two different transcription systems, NEP and PEP, during germination and early seedling development on the mRNA and protein level. Experiments have been performed with two different plant species, Arabidopsis (Arabidopsis thaliana) and spinach (Spinacia oleracea). Results show that the building up of the two different transcription systems is different in the two species. However, in both species NEP as well as PEP are already present in seeds, and results using Tagetin as a specific inhibitor of PEP activity demonstrate that PEP is important for efficient germination, i.e. PEP is already active in not yet photosynthetically active seed plastids.
Extracellular ATP in Plants. Visualization, Localization, and Analysis of Physiological Significance in Growth and Signaling
Authors: Kim Sung-Yong , Sivaguru Mayandi , Stacey Gary 
Published: September 2006

AbstractExtracellular ATP (eATP) in animals is well documented and known to play an important role in cellular signaling (e.g. at the nerve synapse). The existence of eATP has been postulated in plants; however, there is no definitive experimental evidence for its presence or an explanation as to how such a polar molecule could exit the plant cell and what physiological role it may play in plant growth and development. The presence of eATP in plants (Medicago truncatula) was detected by constructing a novel reporter; i.e. fusing a cellulose-binding domain peptide to the ATP-requiring enzyme luciferase. Application of this reporter to plant roots allowed visualization of eATP in the presence of the substrate luciferin. Luciferase activity could be detected in the interstitial spaces between plant epidermal cells and predominantly at the regions of actively growing cells. The levels of eATP were closely correlated with regions of active growth and cell expansion. Pharmacological compounds known to alter cytoplasmic calcium levels revealed that ATP release is a calcium-dependent process and may occur through vesicular fusion, an important step in the polar growth of actively growing root hairs. Reactive oxygen species (ROS) activity at the root hair tip is not only essential for root hair growth, but also dependent on the cytoplasmic calcium levels. Whereas application of exogenous ATP and a chitin mixture increased ROS activity in root hairs, no changes were observed in response to adenosine, AMP, ADP, and nonhydrolyzable ATP (βγmeATP). However, application of exogenous potato (Solanum tuberosum) apyrase (ATPase) decreased ROS activity, suggesting that cytoplasmic calcium gradients and ROS activity are closely associated with eATP release.
Arabidopsis Seed Development and Germination Is Associated with Temporally Distinct Metabolic Switches
Authors: Fait Aaron , Angelovici Ruthie , Less Hadar , Ohad Itzhak , Urbanczyk-Wochniak Ewa , Fernie Alisdair R. , Galili Gad 
Published: September 2006

AbstractWhile the metabolic networks in developing seeds during the period of reserve accumulation have been extensively characterized, much less is known about those present during seed desiccation and subsequent germination. Here we utilized metabolite profiling, in conjunction with selective mRNA and physiological profiling to characterize Arabidopsis (Arabidopsis thaliana) seeds throughout development and germination. Seed maturation was associated with a significant reduction of most sugars, organic acids, and amino acids, suggesting their efficient incorporation into storage reserves. The transition from reserve accumulation to seed desiccation was associated with a major metabolic switch, resulting in the accumulation of distinct sugars, organic acids, nitrogen-rich amino acids, and shikimate-derived metabolites. In contrast, seed vernalization was associated with a decrease in the content of several of the metabolic intermediates accumulated during seed desiccation, implying that these intermediates might support the metabolic reorganization needed for seed germination. Concomitantly, the levels of other metabolites significantly increased during vernalization and were boosted further during germination sensu stricto, implying their importance for germination and seedling establishment. The metabolic switches during seed maturation and germination were also associated with distinct patterns of expression of genes encoding metabolism-associated gene products, as determined by semiquantitative reverse transcription-polymerase chain reaction and analysis of publicly available microarray data. When taken together our results provide a comprehensive picture of the coordinated changes in primary metabolism that underlie seed development and germination in Arabidopsis. They furthermore imply that the metabolic preparation for germination and efficient seedling establishment initiates already during seed desiccation and continues by additional distinct metabolic switches during vernalization and early germination.