bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel Roles of the Master Transcription Factors Spo0A and σBfor Survival and Sporulation ofBacillus subtilisat Low Growth Temperature
Authors: Méndez Marcelo B. , Orsaria Lelia M. , Philippe Valeria , Pedrido María Eugenia , Grau Roberto R. 
Published: February 2004

ABSTRACTSpore development and stress resistance inBacillus subtilisare governed by the master transcription factors Spo0A and σB, respectively. Here we show that the coding genes for both regulatory proteins are dramatically induced, during logarithmic growth, after a temperature downshift from 37 to 20°C. The loss of σBreduces the stationary-phase viability of cold-adapted cells 10- to 50-fold. Furthermore, we show that σBactivity is required at a late stage of development for efficient sporulation at a low temperature. On the other hand, Spo0A loss dramatically reduces the stationary-phase viability of cold-adapted cells 10,000-fold. We show that the requirement of Spo0A for cellular survival during the cold is independent of the activity of the key transition state regulator AbrB and of the simple loss of sporulation ability. Furthermore, Spo0A, and not proficiency in sporulation, is required for the development of complete stress resistance of cold-adapted cells to heat shock (54°C, 1 h), since a loss of Spo0A, but not a loss of the essential sporulation transcription factor σF, reduced the cellular survival in response to heat by more than 1,000-fold. The overall results argue for new and important roles for Spo0A in the development of full stress resistance by nonsporulating cells and for σBin sporulation proficiency at a low temperature.
SONS AND MOTHERS IN WARRING STATES AND HAN CHINA, 453 BCE-220 CE
Authors: Brown Miranda 
Published: January 2004

AbstractThis article examines the startling attention accounts of Eastern Han (24-220 CE) mourning give to depictions of the mother-son bond. Such attention can be explained in terms of the rise of cultural stereotypes about the bonds between mothers and sons, as well as fathers and sons, from the first century BCE. Whereas elite thinkers and statesmen claimed that the relationship between fathers and sons was more analogous to official duty, they regarded the relationship between mother and son as emotional, personal (si), and close (qin). As such, the mother-son bond came to represent an ideological alternative to the early Han ethos of official service, an ethos epitomized by the slogan, "duty to lord and father" (junfu zhi yi).
BONDING, BENEVOLENCE, BARTER, AND BRIBERY: IMAGES OF FEMALE GIFT EXCHANGE IN THE JIN PING MEI
Authors: Dauncey Sarah 
Published: January 2004

AbstractThis article examines images of the practice of gift exchange among women in the late Ming. Despite the fact that the majority of orthodox historical and didactic sources overlook such activity among women, other sources such as the novel Jin Ping Mei reveal perceptions that gift-giving practices were common among women and could be used to facilitate many forms of social action. While highlighting the more mundane use of gifts in lieu of cash and the darker aspect of gift exchange for bribery, the fictional world of the Jin Ping Mei also reflects the socially significant practices of dowry preparation, betrothal gift presentation, and the everyday exchange of gifts to develop friendships and relationships.
The integrated use of chemical insecticides and the entomopathogenic nematode, Steinernema feltiae, for the control of sweetpotato whitefly, Bemisia tabaci
Authors: Cuthbertson Andrew , Head Justine , Walters Keith , Murray Alistair 
Published: February 2004

AbstractThe integration of infective juveniles of the entomopathogenic nematode, Steinernema feltiae, with chemical insecticides to control second instar stages of the sweetpotato whitefly, Bemisia tabaci, was investigated. The effects of direct exposure for 24 h to field rate dilutions of four insecticides (imidacloprid, buprofezin, teflubenzuron and nicotine) on nematode infectivity to Galleria mellonella larvae were tested in a sand tube bioassay. Teflubenzuron had the least adverse effect on the nematodes whilst imidacloprid, buprofezin and nicotine significantly reduced nematode infectivity. The impact of dry insecticide residue present on tomato and verbena foliage on nematode infectivity against B. tabaci larvae was investigated for buprofezin, teflubenzuron and nicotine (imidacloprid is a systemic pesticide and no residues would occur on foliage). No significant reduction on the level of control of B. tabaci was recorded when compared with the infectivity of nematodes applied to residue-free foliage of either tomato or verbena plants. Nematodes in combination with imidacloprid gave significantly higher B. tabaci larvae mortality compared to either treatment individually on both host plants. The integration of S. feltiae and these chemical agents into an integrated pest management programme for the control of B. tabaci is discussed.
Novel nuclear magnetic resonance techniques for the study of quadrupolar nuclei in clays and other layered materials
Authors: Rocha J . , Morais C. M. , Fernandez C. 
Published: January 2004

AbstractThe main developments taking place in Nuclear Magnetic Resonance Spectroscopy (NMR) of quadrupolar (spin I > 1/2) nuclei with half integer spins in solids, particularly clays and other layered materials, have been reviewed. The advent of Multiple-Quantum (MQ) Magic-Angle Spinning (MAS) NMR spectroscopy has been a step-change development to the studies of quadrupolar nuclei in solids. It is now possible to record high-resolution spectra of important nuclei, such as 11B, 17O, 23Na, 27Al and 69,71Ga, in synthetic and natural clays. Since its introduction in 1995 MQMAS NMR has evolved considerably and, at present, a range of very useful related techniques are available and have been reviewed, as has the current situation with regard to applications to clays and other layered materials.
Titanium coordination in silicate glasses investigated using O K-edge X-ray absorption spectroscopy
Authors: Henderson G. S. , Liu Xiaoyang , Fleet M. E. 
Published: January 2004

AbstractA series of titanium silicate glasses along the composition joins TiO2-SiO2, TiO2-Na2SiO3, TiO2-K2SiO3 and TiO2-CaSiO3, has been examined using oxygen K-edge X-ray absorption near edge structure spectroscopy (XANES) confined to the near-surface region. Sharp pre-edge features in the spectra can be used to determine the Ti coordination in the glasses. The presence of [4]Ti is indicated by a pre-edge peak at ∼534 eV while [5]Ti is indicated by a peak at ∼533 eV. Titanium exists in all these glasses as [4]Ti and [5]Ti with no [6]Ti being present. For alkali-containing glasses the [5]Ti site becomes more prevalent with increasing TiO2. TiO2-K2SiO3 compositions contain a greater proportion of [4]Ti than comparable Na2O compositions. This is consistent with earlier Ti L-edge findings. The TEY spectra for the TiO2-CaSiO3 compositions indicate the presence of significant amounts of [5]Ti at high TiO2 contents; however, comparison of TEY (near surface) and FY (bulk sample) XANES shows that the [5]Ti is confined to the surface of the glass sample with the bulk of the glass containing [4]Ti.
Water solubility and diffusivity in olivine: its role in planetary tectonics
Authors: Regenauer-Lieb K. , Kohl T. 
Published: January 2004

AbstractNew constraints on the thermodynamic equation of state of water and the predicted water fugacity dependence of OH-solubility at elevated P-T conditions along with its influence on dislocation dynamics in olivine are reviewed. Water is shown to control the style of tectonics of a planetary lithosphere by switching on highly localized weak faulting instead of a broad, slow creeping flow. The transition occurs above a water concentration of 200 ppm H/Si. We argue that this changeover in style of tectonics has important implications for the mechanics of subduction and for plate tectonics in general. Efficient recycling of water is only given if the top strong part of the lithosphere can fail and be dragged down into the mantle in a steady way. Due to different starting conditions and differences in accretion through planetismals, Venus may have never have reached a water content above 200 ppm H/Si in the upper mantle while Mars would have now left the plate tectonic regime due to fast cooling.
Using neutron diffraction measurements to characterize the mechanical properties of polymineralic rocks
Authors: Schofield P. F. , Covey-Crump S. J. , Stretton I. C. , Daymond M. R. , Knight K. S. , Holloway R. F. 
Published: January 2004

AbstractConventional experiments designed to investigate the mechanical properties of polycrystalline geological materials are generally restricted to measurements of whole-rock properties. However, when comparing the measurements with theoretical models, it is frequently essential to understand how the deformation is accommodated at the grain-scale. This is particularly true for polymineralic rocks because in this case most theories express the whole-rock properties as some function of the properties of their constituent minerals, and hence the contribution which each phase makes to those properties must be measured if the theories are to be fully assessed. The penetrating nature of neutrons offers a method of addressing this problem. By performing deformation experiments in the neutron beam-line and collecting neutron diffraction patterns at different applied loads, the lattice parameters of all the mineral phases present may be determined as a function of load. The elastic strain experienced by each phase is then easily determined. Moreover, the strain in different lattice directions is also obtained. From this information a wide range of problems relevant for the characterization of the elastic and plastic deformation behaviour of polymineralic geological materials can be explored. An experimental technique for carrying out such experiments is described, and its validity is demonstrated by showing that the results obtained from deforming an elastically isotropic olivine + magnesiowüstite sample agree, to within very tight bounds, with the behaviour predicted by theory for elastically isotropic composites.
First occurrence of the rare ‘corundum + quartz’ assemblage in the high-grade zone from the Namaqualand Metamorphic Complex, South Africa: evidence for higher-P, T metamorphism?
Authors: Mouri H. , Andreoli M. A. G. , Kienast J. R. , Guiraud M. , De Waal S. A. 
Published: January 2004

AbstractWe report in this paper the first occurrence of the rare assemblage corundum + quartz in the high-grade metamorphic zone in the core of the Namaqualand Metamorphic Complex (NMC) (South Africa). The magnetite-bearing rocks hosting the corundum-quartz assemblage are very rare, and occur discontinuous bands a few cm wide, associated with diorite, tonalite and anorthosite within quartzfeldspar ± sillimanite ± biotite ± spinel supracrustal rocks extensively intruded by a foliated granite gneiss. The magnetite-bearing rocks are characterized by the presence of abundant crystals of magnetite together with ilmenite, spinel and large (∽1 cm in diameter) euhedral crystals of corundum both displaying a sharp contact with magnetite and quartz. However, in some micro-domains, spinel and quartz, as well as corundum and quartz, are separated by a thin corona of sillimanite with or without magnetite. These textural features suggest that the following reactions have taken place: quartz + corundum → sillimanite, and quartz + spinel + O2 → sillimanite + magnetite. These reactions are interpreted as occurring at higher, as yet unknown, P-T conditions than previously estimated for the NMC. Whether corundum and quartz were once in equilibrium is worth investigating, as it could constitute a geothermobarometric assemblage for ultra-high T granulites.
The Early Proterozoic carbonatite complex of Angico dos Dias, Bahia State, Brazil: geochemical and Sr-Nd isotopic evidence for an enriched mantle origin
Authors: Antonini P. , Comin-chiaramonti P. , Gomes C. B. , Censi P. , Riffel B. F. , Yamamoto E. 
Published: January 2004

AbstractBorehole samples of carbonatites and phlogopite-pyroxenites from the Angico dos Dias (AdD) intrusive alkaline complex, State of Bahia, Brazil, have been investigated in terms of mineralogy, geochemistry and C-O-Sr-Nd isotopes. The AdD complex, of Early Proterozoic age (2 Ga), intrudes the northern side of the São Francisco Craton. Mineralogy and petrography indicate that the studied rocks only partially preserved their magmatic textural features owing to their metamorphic re-equilibration (greenschist facies). The REE contents and LREE/HREE ratios of the AdD carbonatites are very high (mean 3979±718 ppm and La/Yb = 215±23, respectively), as for most Precambrian magmatic carbonatites. The AdD carbonatites are also enriched in 18O (δ18O = 11.9 to 15.8‰), possibly due to secondary processes (e.g. metamorphism, alteration) whereas carbon isotopes are in the range of ‘primary carbonatites’ (δ13C = –5.7 to –7.1‰). Most of the initial 87Sr/86Sr and 143Nd/144Nd values of the studied carbonatites were not appreciably modified by secondary processes. Their εtSr and εtNd values (20.0 to 25 and 0.7 to –4.5, respectively) indicate enriched mantle sources very different from the ‘depleted’ ones related to many Precambrian carbonatites from North America (0.6 –2.6 Ga) and Africa (0.5 –2.0 Ga). The Early Proterozoic Sr-Nd isotopic signatures of the AdD carbonatites are similar to those of the Early Cretaceous carbonatites from the Paraná basin. The latter carbonatites show a great isotopic variability ranging from Bulk Earth to the related potassic magmatism from Asunción-Sapucai graben in the Eastern Paraguay (K-ASU magmatism: εtSr = 35 to 50 and εtNd = –12 to –20). The very similar isotopic compositions of Precambrian and post-Palaeozoic carbonatites worldwide indicate that the subcontinental mantle variability lasted for long periods of time and indicate a large-scale mantle heterogeneity.
Iron sulphides at the epithermal gold-copper deposit of Palai-Islica (Almería, SE Spain)
Authors: Carrillo Rosúa F. J. , Morales Ruano S. , Fenoll Hach-Alí P. 
Published: January 2004

AbstractAu-Cu mineralization at Palai-Islica occurs as disseminations in massive silicified volcanic rocks and, more abundantly, in sulphide-bearing quartz veins. The major ore minerals in the deposit are pyrite ± chalcopyrite, sphalerite and galena and there is a great variety of accessory minerals, including Au-Ag alloys and native gold. Pyrite, the most abundant sulphide, is closely associated with gold. Seven different types of pyrite have been distinguished with a variable concentration of different trace elements. Among these, the only one free of trace elements (type IV) is related to Au-Ag alloys. Pyrite associated with these Au-Ag alloys has cubic and pentagonal dodecahedral habits, whereas pyrite with pentagonal dodecahedral habit only is from barren zones. In addition, there is no significant invisible gold in the pyrite, but there is a relatively large amount of Ag in collomorphic pyrite (up to 0.20 wt.%) or type III pyrite (up to 1.47 wt.%). Arsenic is the most abundant trace element in pyrite (up to 6.11 wt.%), present as a metastable solid solution or as a non-stoichiometric element. A variety of marcasite related to the gold levels also has a considerable amount of trace elements (As up to 1.15 wt.%, Sb up to 0.40 wt.%).
Prismatine and ferrohögbomite-2N2Sin granulite-facies Fe-oxide lenses in the Eastern Ghats Belt at Venugopalapuram, Vizianagaram district, Andhra Pradesh, India: do such lenses have a tourmaline-enriched lateritic precursor?
Authors: Grew E. S. , Rao A. T. , Raju K. K. V. S. , Hejny C. , Moore J. M. , Waters D. J. , Yates M. G. , Shearer C. K. 
Published: January 2004

AbstractFluorine-rich prismatine, (□,Fe,Mg)(Mg,Al,Fe)5Al4(Si,B,Al)5O21(OH,F), with F/(OH+F) = 0.36–0.40 and hercynite are major constituents of a Fe-Al-B-rich lens in ultrahigh-temperature granulite-facies quartz-sillimanite-hypersthene-cordierite gneisses of the Eastern Ghats belt, Andhra Pradesh, India. Hemo-ilmenite, sapphirine, magnetite, biotite and sillimanite are subordinate. Lithium, Be and B are concentrated in prismatine (140 ppm Li, 170 ppm Be, and 2.8 –3.0 wt.% B2O3). Another Fe-rich lens is dominantly magnetite, which encloses fine-grained zincian ferrohögbomite-2N2S, (Fe2+,Mg,Zn,Al)6(Al,Fe3+,Ti)16O30(OH)2, containing minor Ga2O3(0.30 –0.92 wt.%). Fe-Al-B-rich lenses with prismatine (or kornerupine) constitute a distinctive type of B-enrichment in granulite-facies rocks and have been reported from four other localities worldwide. A scenario involving a tourmalineenriched lateritic precursor affected by dehydration melting is our preferred explanation for the origin of the Fe-Al-B-rich lenses at the five localities. Whole-rock analyses and field relationships at another of these localities, Bok se Puts, Namaqualand, South Africa, are consistent with this scenario. Under granulite-facies conditions, tourmaline would have broken down to give kornerupine-prismatine (±other borosilicates) plus a sodic melt containing H2O and B. Removal of this melt depleted the rock in Na and B, but the formation of ferromagnesian borosilicate phases in the restite prevented total loss of B.
Carbonatites and lamprophyres of the Gardar Province – a ‘window’ to the sub-Gardar mantle?
Authors: Coulson I. M. , Goodenough K. M. , Pearce N. J. G. , Leng M. J. 
Published: January 2004

AbstractCarbonatite magmas are considered to be ultimately derived from mantle sources, which may include lithospheric and asthenospheric reservoirs. Isotopic studies of carbonatite magmatism around the globe have typically suggested that more than one source needs to be invoked for generation of the parental melts to carbonatites, often involving the interaction of asthenosphere and lithosphere.In the rift-related, Proterozoic Gardar Igneous Province of SW Greenland, carbonatite occurs as dykes within the Igaliko Nepheline Syenite Complex, as eruptive rocks and diatremes at Qassiarsuk, as a late plug associated with nepheline syenite at Grønnedal-Íka, and as small bodies associated with ultramafic lamprophyre dykes. The well-known cryolite deposit at Ivittuut was also rich in magmatic carbonate. The carbonatites are derived from the mantle with relatively little crustal contamination, and therefore should provide important information about the mantle sources of Gardar magmas. In particular, they are found intruded both into Archaean and Proterozoic crust, and hence provide a test for the involvement of lithospheric mantle.A synthesis of new and previously published major and trace element, Sr, Nd, C and O isotope data for carbonatites and associated lamprophyres from the Gardar Province is presented. The majority of Gardar carbonatites and lamprophyres have consistent geochemical and isotopic signatures that are similar to those typically found in ocean island basalts. The geochemical characteristics of the two suites of magmas are similar enough to suggest that they were derived from the same mantle source. C and O isotope data are also consistent with a mantle derivation for the carbonatite magmas, and support the theory of a cogenetic origin for the carbonatites and the lamprophyres. The differences between the carbonatites and lamprophyres are considered to represent differing degrees of partial melting of a similar source.We suggest that the ultimate source of these magmas is the asthenospheric mantle, since there is no geochemical or isotopic evidence for their having been derived directly from ancient, enriched sub-continental lithospheric mantle. However, it is likely that the magmas actually formed through a two-stage process, with small-degree volatile-rich partial melts rising from the asthenospheric mantle and being ‘frozen in’ as metasomites, which were then rapidly remobilized during Gardar rifting.
Ilímaussaq ‘en miniature’: closed-system fractionation in an agpaitic dyke rock from the Gardar Province, South Greenland (contribution to the mineralogy of Ilímaussaq no. 117)
Authors: Marks M. , Markl G. 
Published: January 2004

AbstractBased on petrography, mineral chemistry, and petrology, the physico-chemical evolution of an agpaitic dyke was found to be very similar to that of the neighbouring Ilímaussaq complex. Various mineral assemblages were used to reconstruct the crystallization conditions of the dyke rock for different stages during cooling. The early magmatic phenocryst assemblage is alkali feldspar + nepheline + augite + olivine + magnetite and indicates liquidus temperatures of ∼850ºC, silica activities of ∼0.5, and oxygen fugacities of FMQ –1.5 to –3. The groundmass assemblage albite + microcline + nepheline + sodalite + arfvedsonite + aegirine + aenigmatite + astrophyllite indicates lower temperatures of between 600 and 450ºC, at silica activities of 0.25, and oxygen fugacities around the FMQ buffer. Amphibole composition strongly responds to fluorite saturation and proves crystallization occurred in a system closed to oxygen. Late-stage hydrothermal conditions are indicated by the conversion of nepheline and sodalite to analcime and the growth of aegirine on arfvedsonite. These late-stage reactions are constrained to temperatures of <300°C, water activities of between 0.5 and unity, and oxygen fugacities above MH. The dyke has to be regarded as a small equivalent of the larger Ilímaussaq complex, in which identical differentiation processes proceeded at a scale very different in terms of magma volume and cooling times.
Trace-element content and partitioning in calcite, dolomite and apatite in carbonatite, Phalaborwa, South Africa
Authors: Dawson J. B. , Hinton R. W. 
Published: January 2004

AbstractA carbonatite sample from Phalaborwa, South Africa, consists of apatite, magnetite and a calcitedolomite ‘perthite’ which is interpreted as being due to exsolution of dolomite from a high-Mg calcite precursor. Carbon and oxygen isotope data indicate that the carbonates are equilibrated. In situ ionmicroprobe analyses for Fe, Mn, Na, Si, Y, the REEs, Pb, Th and U give the following average concentrations (in ppm) in the sequence apatite, calcite, dolomite: Fe 98, 1680, 8190; Mn 61, 510, 615; Na 1171, 627, 125; Si 368; 1.6, 0.2; Sr 4447, 5418, 2393; Ba 37, 2189, 75; La 1245, 300, 67; Y 121, 50, 5.8; Pb 16, 5.4, 1.4; Th 20, 0.02, 0; U 2.4, 0, 0.01. The concentrations are reasonably uniform in both apatite and dolomite, but in calcite are more variable. Na, Si, Y, the REEs, Pb, Th and U partition into apatite relative to both carbonates (and, hence, the precursor carbonate); KD ap/cc for REE decreases from ∽4 for La to ∽2 for Tm. There is almost equal partitioning of Sr between apatite and calcite. During separation of dolomite from calcite, Sr and Ba partition strongly into calcite and all the other analysed elements, except Fe and Mn, also preferentially enter calcite. The REEs prefer calcite relative to dolomite, and the KD dol/cc is reasonably constant, only varying from 0.23 to 0.17. Sr, Ba and Pb in the carbonates, and their partitioning between the calcite and dolomite, differ from other carbonatite carbonates reported in the literature.