bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE NON-COMMUTATIVE A-POLYNOMIAL OF TWIST KNOTS
Authors: GAROUFALIDIS STAVROS , SUN XINYU 
Published: January 2011

The purpose of the paper is two-fold: to introduce a multivariable creative telescoping method, and to apply it in a problem of Quantum Topology: namely the computation of the non-commutative A-polynomial of twist knots. Our multivariable creative telescoping method allows us to compute linear recursions for sums of the form [Formula: see text] given a recursion relation for [Formula: see text] and the hypergeometric kernel c(n, k). As an application of our method, we explicitly compute the non-commutative A-polynomial for twist knots with -15 and 15 crossings. The non-commutative A-polynomial of a knot encodes the monic, linear, minimal order q-difference equation satisfied by the sequence of colored Jones polynomials of the knot. Its specialization to q = 1 is conjectured to be the better-known A-polynomial of a knot, which encodes important information about the geometry and topology of the knot complement. Unlike the case of the Jones polynomial, which is easily computable for knots with 50 crossings, the A-polynomial is harder to compute and already unknown for some knots with 12 crossings.
Geochemical indicators of metalliferous fertility in the Carboniferous San Blas pluton, Sierra de Velasco, Argentina
Authors: Rossi J. N. , Toselli A. J. , Basei M. A. , Sial A. N. , Baez M. 
Published: January 2011

Abstract

In the Sierra de Velasco, northwestern Argentina, undeformed Lower Carboniferous granitoids (350–334 Ma) intrude deformed Lower Ordovician granites and have been emplaced by passive mechanisms, typical of tensional environments. The semi-elliptic, about 300 km
2
shallow-emplaced San Blas pluton is 340–330 Ma old, with εNd
t
between −1.3 and −1.8 which indicates that, different from the nearby Famatinian–Ordovician granitoids, the San Blas pluton had a relatively brief crustal residence, with an interaction between asthenospheric material and greywackes. The cupola of the pluton was almost totally eroded down during the Upper Carboniferous.

The San Blas pluton is a porphyritic granite composed mainly of monzogranite to syenogranite and shows graphic intergrowth and miarolitic cavities up to 5 cm in diameter, filled with quartz. Two different textures are recognized: perthitic microcline megacrysts (30–45 vol%) set in a medium- to coarse-grained groundmass of quartz, microcline and oligoclase, with sericitic alteration. Biotite, muscovite, apatite, zircon, fluorite and opaque minerals are the accessory phases. The other textural variation consists in microcline megacrysts (10%–15 vol%) and a fine-grained groundmass, of quartz, microcline and oligoclase, biotite, apatite, muscovite, zircon and magnetite.

The average SiO
2
content in this pluton is 74.94%, the ASI=1.1, CaO and MgO are less than 1%, total Fe
2
O
3
and P
2
O
5
contents are low, and K
2
O>Na
2
O. Low Ba, Sr and high Rb contents, coupled with Sn contents (
c.
15 ppm), W (
c.
380 ppm), Nb, Y, Ta, Th and U confirm this is a special granite. The K/Rb ratio (
c.
75) indicates that Rb has been fractionated to the residual melt whereas the Zr/Hf (
c.
25) demonstrates that hydrothermal alteration occurred. The Sr/Eu ratio of
c.
75 along other geochemical features characterize this pluton as a fertile evolved granite.

The chondrite-normalized rare earth element (REE) diagram shows the tetrad effect that allows the subdivision of the lanthanides into four groups.
In general, the tetrad effect is recognized in evolved granites and products of hydrothermal alteration such as greisens. The above-mentioned features show that the San Blas granite is fertile, and the absence of ore deposits has been probably caused by erosion of a mineralized cupola during Carboniferous and Cenozoic exhumation. The finding of alluvial cassiterite and wolframite in drainage systems is the first evidence of the fertile character of this granite.
Evolution of metallogeny of granitic pegmatites associated with orogens throughout geological time
Authors: Tkachev A. V. 
Published: January 2011

Abstract

Since
c.
3.1 Ga, pegmatite mineral deposits in orogenic areas have been formed throughout geological time in pulses, alternating with total absence of generating activity. The higher activity peaks of 2.65–2.60, 1.90–1.85, 1.00–0.95, and 0.30–0.25 Ga suggest a quasi-regular periodicity of 0.8±0.1 Ga. This series is dominated by pegmatites of Laurasian blocks. The lower peaks at 2.85–2.80, 2.10–2.05, 1.20–1.15, and the higher one at 0.55–0.50 make up another series represented by pegmatites in Gondwanan blocks only. Each pegmatite class is characterized by a life cycle of its own, from inception to peak through to decline and eventual extinction. The longest cycle is recorded for the rare-metal class deposits, which first appeared in the Mesoarchaean and persisted through all the later eras, deteriorating gradually after the Early Precambrian. Muscovite pegmatites first appeared in the Palaeoproterozoic and reached the end of their life cycle at the Palaeozoic–Mesozoic boundary. The miarolitic class of pegmatite deposits in orogenic setting first came into being in the terminal Mesoproterozoic and dominated the pegmatite metallogeny of many Phanerozoic belts. The evolution of the pegmatite classes was controlled by the general cooling of the Earth and by associated changes in the tectonics of the lithosphere.

Supplementary material:

Geochronological data used is available at
http://www.geolsoc.org.uk/SUP18435
.
Late Neoproterozoic-Cambrian granitic magmatism in the Araçuaí orogen (Brazil), the Eastern Brazilian Pegmatite Province and related mineral resources
Authors: Pedrosa-Soares A. C. , De Campos Cristina P. , Noce Carlos , Silva Luiz Carlos , Novo Tiago , Roncato Jorge , Medeiros Sílvia , Castañeda Cristiane , Queiroga Gláucia , Dantas Elton , Dussin Ivo , Alkmim Fernando 
Published: January 2011

Abstract

The Araçuaí orogen extends from the eastern edge of the São Francisco craton to the Atlantic margin, in southeastern Brazil. Orogenic igneous rocks, formed from
c.
630 to
c.
480 Ma, cover one third of this huge area, building up the Eastern Brazilian Pegmatite Province and the most important dimension stone province of Brazil. G1 supersuite (630–585 Ma) mainly consists of tonalite to granodiorite, with mafic to dioritic facies and enclaves, representing a continental calc-alkaline magmatic arc. G2 supersuite mostly includes S-type granites formed during the syn-collisional stage (585–560 Ma), from relatively shallow two-mica granites and related gem-rich pegmatites to deep garnet-biotite granites that are the site of yellow dimension stone deposits. The typical G3 rocks (545–525 Ma) are non-foliated garnet-cordierite leucogranites, making up autochthonous patches and veins. At the post-collisional stage (530–480 Ma), G4 and G5 supersuites were generated. The S-type G4 supersuite mostly consists of garnet-bearing two-mica leucogranites that are the source of many pegmatites mined for tourmalines and many other gems, lithium (spodumene) ore and industrial feldspar. G5 supersuite, consisting of high-K–Fe calc-alkaline to alkaline granitic and/or charnockitic to dioritic/noritic intrusions, is the source of aquamarine-topaz-rich pegmatites but mainly of a large dimension stone production.
Tourmaline nodules: products of devolatilization within the final evolutionary stage of granitic melt?
Authors: Balen Dražen , Broska Igor 
Published: January 2011

Abstract

The origin of tourmaline nodules, and of their peculiar textures found in peripheral parts of the Moslavačka Gora (Croatia) Cretaceous peraluminous granite are connected with the separation of a late-stage boron-rich volatile fluid phase that exsolved from the crystallizing magma. Based on field, mineralogical and textural observations, tourmaline nodules were formed during the final stage of granite evolution when undersaturated granite magma intruded to shallow crustal horizons, become saturated and exsolved a fluid phase from residual melt as buoyant bubbles, or pockets. Calculated
P–T
conditions at emplacement level are
c.
720 °C, 70–270 MPa, and water content in the melt up to 4.2 wt%.

Two distinct occurrence types of tourmalines have been distinguished: disseminated and nodular tourmalines. Disseminated tourmaline, crystallized during magmatic stage, is typical schorl while nodular tourmaline composition is shifted toward dravite. The increase of dravite in nodular tourmaline is attributed to mixing of the fluid phase from the residual melt with fluid from the wall rocks.
The pressure decrease and related cooling at shallow crustal levels can be considered as a major factor controlling fluid behaviour, formation of a volatile phase, and the crystallization path in the Moslavačka Gora granite body.
Geochemical characteristics of Miocene Fe-Cu–Pb–Zn granitoids associated mineralization in the Chichibu skarn deposit (central Japan): evidence for magmatic fluids generation coexisting with granitic melt
Authors: Ishiyama D. , Miyata M. , Shibata S. , Satoh H. , Mizuta T. , Fukuyama M. , Ogasawara M. 
Published: January 2011

Abstract

In this work we study mechanisms and timing of magmatic fluid generation during magma emplacement. Our focus is the Miocene calc-alkaline granitic rocks from the Chichibu mining area, in Japan. The granitoids consist of northern and southern Bodies and of the Daikoku Altered stocks. Cathodoluminescence observation of quartz phenocrysts from the northern body point towards magmatic resorption, which is thought to be caused by mixing between a more differentiated and a more primitive magma. The coexistence of vapour-rich two-phase and halite-bearing polyphase fluid inclusions in a single quartz crystal from the northern Body supports the possibility of pressure decrease during magma emplacement. The magmatic fluids that originated the Chichibu deposit are thought to have been generated by pressure release, related to magmatic differentiation when the SiO
2
-content reaches about 65 wt%. As a result, heavy metals, such as copper, gold and arsenic, coexisting with the silicate melt, were transported into the sedimentary strata through degassing of magmatic fluids. A later major fault system caused the intercalation between heavy-metal-free limestone and orebodies, as a secondary skarn-building process took place in the dominant limestone area.
Fixed Point Theorems for Monotone Mappings on Partial Metric Spaces
Authors: Altun Ishak , Erduran Ali 
Published: January 2011

AbstractMatthews (1994) introduced a new distance "Equation missing" on a nonempty set "Equation missing", which is called partial metric. If "Equation missing" is a partial metric space, then "Equation missing" may not be zero for "Equation missing". In the present paper, we give some fixed point results on these interesting spaces.
S100A8/A9 Activate Key Genes and Pathways in Colon Tumor Progression
Authors: Ichikawa Mie , Williams Roy , Wang Ling , Vogl Thomas , Srikrishna Geetha 
Published: January 2011

AbstractThe tumor microenvironment plays an important role in modulating tumor progression. Earlier, we showed that S100A8/A9 proteins secreted by myeloid-derived suppressor cells (MDSC) present within tumors and metastatic sites promote an autocrine pathway for accumulation of MDSC. In a mouse model of colitis-associated colon cancer, we also showed that S100A8/A9-positive cells accumulate in all regions of dysplasia and adenoma. Here we present evidence that S100A8/A9 interact with RAGE and carboxylated glycans on colon tumor cells and promote activation of MAPK and NF-κB signaling pathways. Comparison of gene expression profiles of S100A8/A9-activated colon tumor cells versus unactivated cells led us to identify a small cohort of genes upregulated in activated cells, including Cxcl1, Ccl5 and Ccl7, Slc39a10, Lcn2, Zc3h12a, Enpp2, and other genes, whose products promote leukocyte recruitment, angiogenesis, tumor migration, wound healing, and formation of premetastatic niches in distal metastatic organs. Consistent with this observation, in murine colon tumor models we found that chemokines were upregulated in tumors, and elevated in sera of tumor-bearing wild-type mice. Mice lacking S100A9 showed significantly reduced tumor incidence, growth and metastasis, reduced chemokine levels, and reduced infiltration of CD11b+Gr1+ cells within tumors and premetastatic organs. Studies using bone marrow chimeric mice revealed that S100A8/A9 expression on myeloid cells is essential for development of colon tumors. Our results thus reveal a novel role for myeloid-derived S100A8/A9 in activating specific downstream genes associated with tumorigenesis and in promoting tumor growth and metastasis. Mol Cancer Res; 9(2); 133–48. ©2011 AACR.
Improved Survival in Heart Transplant Recipients in the United States
Authors: Singh Tajinder P. , Almond Christopher , Givertz Michael M. , Piercey Gary , Gauvreau Kimberlee 
Published: January 2011

Background—Posttransplant survival in heart transplant recipients has progressively improved during the past 2 decades. It is unknown, however, whether the major racial groups in the United States have benefited equally.Methods and Results—We analyzed all primary heart transplant recipients aged ≥18 years in the United States from 1987 to 2008. We compared posttransplant survival in white, black, and Hispanic recipients in 5 successive eras (1987 to 1992, 1993 to 1996, 1997 to 2000, 2001 to 2004, 2005 to 2008). Early survival was defined as freedom from death or retransplantation during the first 6 months posttransplant. Longer-term, conditional survival was assessed in patients who survived the first 6 months. There were 29 986 (81.6%) white, 4745 (12.9%) black, and 2017 (5.5%) Hispanic patients in the study cohort. Black patients were at increased risk of early death or retransplant (hazard ratio [HR], 1.15; 95% CI, 1.05 to 1.26) in adjusted analysis. Early posttransplant survival improved (HR, 0.83; 95% CI, 0.80 to 0.87 for successive eras) equally in all 3 groups (black-era interaction,P=0.94; Hispanic-era interaction,P=0.40). Longer-term survival improved in white (HR, 0.95; 95% CI, 0.92 to 0.97 for successive eras) but not in black (HR, 1.04; 95% CI, 0.99 to 1.09) or Hispanic (HR, 1.02; 95% CI, 0.95 to 1.09) recipients, resulting in increased disparities in longer-term survival with time.Conclusions—Early posttransplant survival has improved equally in white, black, and Hispanic heart transplant recipients. Longer-term survival has improved in white but not in black or Hispanic recipients, resulting in a more marked disparity in outcomes in the current era. These disparities warrant further investigation and targeted interventions.
Trade Wind Cloud Evolution Observed by Polarization Radar: Relationship to Giant Condensation Nuclei Concentrations and Cloud Organization
Authors: Minor Hilary A. , Rauber Robert M. , Göke Sabine , Di Girolamo Larry 
Published: January 2011

Abstract
Shallow marine trade wind cumuli are one of the most prevalent cloud types in the tropical atmosphere. Understanding how precipitation forms within these clouds is necessary to advance our knowledge concerning their role in climate. This paper presents a statistical analysis of the characteristic heights and times at which precipitation in trade wind clouds passes through distinct stages in its evolution as defined by the equivalent radar reflectivity factor at horizontal polarization ZH, the differential reflectivity ZDR, and the spatial correlation between and averages of these variables. The data were obtained during the Rain in Cumulus over the Ocean (RICO) field campaign by the National Center for Atmospheric Research (NCAR) S-band dual-polarization (S-Pol) Doppler radar, the National Science Foundation (NSF)–NCAR C130 aircraft, and soundings launched near the radar. The data consisted of 76 trade cumuli that were tracked from early echo development through rainout on six days during RICO. Trade wind clouds used in the statistical analyses were segregated based on giant condensation nuclei (GCN) measurements made during low-level aircraft flight legs on the six days.
This study found that the rate of precipitation formation in shallow marine cumulus was unrelated to the GCN concentration in the ambient environment. Instead, the rate at which precipitation developed in the clouds appeared to be related to the mesoscale forcing as suggested by the cloud organization. Although GCN had no influence on the rate of precipitation development, the data suggest that they do contribute to a modification of the rain drop size distribution within the clouds. With very few exceptions, high threshold values of ZDR were found well above cloud base on days with high GCN concentrations. On the days that were exceptions, these threshold values were almost always achieved near cloud base.
Trends in Global and Basin-Scale Runoff over the Late Twentieth Century: Methodological Issues and Sources of Uncertainty
Authors: Alkama R. , Decharme B. , Douville H. , Ribes A. 
Published: January 2011

Abstract
While human influence has been detected in global and regional surface air temperature, detection–attribution studies of direct (i.e., land use and water management) and indirect (i.e., climate related) effects of human activities on land surface hydrology remain a crucial and controversial issue. In the present study, a set of global offline hydrological simulations is performed during the 1960–94 period using the Interactions between Soil, Biosphere, and Atmosphere–Total Runoff Integrating Pathways (ISBA-TRIP) modeling system. In contrast to previous numerical sensitivity studies, the model captures the observed trend in river runoff over most continents without including land use changes and/or biophysical CO2 effects, at least when the comparison is made over 154 large rivers with a minimum amount of missing data. The main exception is northern Asia, where the simulated runoff trend is negative, in line with the prescribed precipitation forcing but in contrast with the observed runoff trend. The authors hypothesize that the observed surface warming and the associated decline of permafrost and glaciers, not yet included in most land surface models, could have contributed to the increased runoff at high latitudes. They also emphasize that the runoff trend is a regional-scale issue, if not basin dependent. In line with recent observational studies, their results suggest that CO2 stomatal conductance effects and land use changes are not the primary drivers of the multidecadal runoff variability at continental scales. However, the authors do not rule out a human influence on land runoff, at least through the high-latitude surface warming observed over recent decades.
Eddy–Mean Flow Interaction in the Kuroshio Extension Region
Authors: Waterman Stephanie , Hogg Nelson G. , Jayne Steven R. 
Published: January 2011

Abstract
The authors use data collected by a line of tall current meter moorings deployed across the axis of the Kuroshio Extension (KE) jet at the location of maximum time-mean eddy kinetic energy to characterize the mean jet structure, the eddy variability, and the nature of eddy–mean flow interactions observed during the Kuroshio Extension System Study (KESS). A picture of the 2-yr record mean jet structure is presented in both geographical and stream coordinates, revealing important contrasts in jet strength, width, vertical structure, and flanking recirculation structure. Eddy variability observed is discussed in the context of some of its various sources: jet meandering, rings, waves, and jet instability. Finally, various scenarios for eddy–mean flow interaction consistent with the observations are explored. It is shown that the observed cross-jet distributions of Reynolds stresses at the KESS location are consistent with wave radiation away from the jet, with the sense of the eddy feedback effect on the mean consistent with eddy driving of the observed recirculations. The authors consider these results in the context of a broader description of eddy–mean flow interactions in the larger KE region using KESS data in combination with in situ measurements from past programs in the region and satellite altimetry. This demonstrates important consistencies in the along-stream development of time-mean and eddy properties in the KE with features of an idealized model of a western boundary current (WBC) jet used to understand the nature and importance of eddy–mean flow interactions in WBC jet systems.
Medicare hospice care in US nursing homes: a 2006 update
Authors: Sterns Samantha , Miller Susan C 
Published: January 2011

Introduction: This research examines 2006 population-based data on persons who died in US nursing homes (NHs) and received hospice in the NH. Methods: We compared dying persons characteristics and lengths of hospice stay in five US states between 1992 and 1996 and in 2006. We also compared characteristics of dying persons in 2006 by whether they first entered hospice in the community (i.e. ‘community-NH’, N = 12,950) or the NH (i.e. ‘NH-only’, N = 159,065). Results: In five US states, dying persons who received NH hospice in 2006, compared to 1992–1996, were older, had more short hospice stays (≤7 days), and were less frequently diagnosed with cancer. Also, in 2006, dying persons receiving ‘NH-only’ versus ‘community-NH’ hospice were older, had more short stays, and were less frequently diagnosed with cancer. Discussion: Persons in 2006 who received hospice in the community and in the NH (vs. ‘NH-only’) were strikingly similar to hospice participants in 1992–1996. 2006 ‘NH-only’ vs. ‘community-NH’ dying persons, more closely resemble U.S. NH residents.