bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the nature of homo- and hetero-dinuclear metal–metal quadruple bonds — Analysis of the bonding situation and benchmarking DFT against wave function methods
Authors: Takagi Nozomi , Krapp Andreas , Frenking Gernot 
Published: November 2010

Homo- and hetero-dimetallic (d–d)8 analogues of the formally quadruply bonded [Re2Cl8]2– system with the general formula [MM′Cl8]x (M, M′ = Tc, Re, Ru, Os, Rh, Ir and x = –2, –1, 0, +1, +2) have been calculated with the density functional theory (DFT) functionals SVWN, BLYP, BP86, PBE, OLYP, OPBE, HCTH, B3LYP, O3LYP, X3LYP, BH&HLYP, TPSS, VSXC, TPPSh, and ab initio methods (CASPT2, CCSD(T)) using basis sets of triple-ζ quality. The performance of the functionals for the description of the metal–metal bond distance and the bond dissociation energy as well as the singlet–triplet gap was evaluated with respect to ab initio data at the CASPT2 level. Generally, the generalized gradient approximation (GGA) functionals, BLYP, BP86, and PBE, show good performance in the description of the metal–metal bond distance and for the dissociation energy. Hybrid functionals are not to be used for compounds of the type discussed here as they lead to increasingly too short and too weak bonds with the amount of exact exchange included. All functionals underestimate the singlet–triplet gap, with the GGA functionals BLYP, BP86, PBE being the closest to the CASPT2 values. The bonding situations of the [MM′Cl8]x compounds were analyzed at the DFT level (BP86) using the natural bond orbital (NBO) method and the energy decomposition analysis. The M–M bond in homodimetallic compounds, [MMCl8]x, becomes weaker from group 7 to group 8 to group 9 metals and the bond is weaker for 4d metal systems than for 5d transition metal compounds. The M–M bonds have approximately 50% covalent and 50% electrostatic character and the covalent contribution is dominated by the π orbitals, whereas the δ orbitals do not contribute significantly to the covalent bonding. Heterodimetallic systems, [MM′Cl8]x, have significantly stronger metal–metal bonds than the homodimetallic compounds. This comes from weaker Pauli repulsion and stronger electrostatic attraction. The most stable heterodimetallic bonds are observed for 5d–5d metal pairs.
Configurations and conformations of glycosyl sulfoxides
Authors: Liang Hong , MacKay Micheline , Grindley T. Bruce , Robertson Katherine N. , Cameron T. Stanley 
Published: November 2010

X-ray crystallographic studies of two axial glycosyl sulfoxides having RS configurations (derivatives of phenyl 2-azido-2-deoxy-1-thio-α-d-galactopyranoside S-oxide) show that they adopt anti conformations in the solid state, in contrast to previous observations and assumptions. Density functional theory (DFT) calculations at the B3lYP6–311G+(d,p)/6–31G(d) level confirm that anti conformations of both phenyl and methyl RS glycosyl sulfoxides of 2-azido-2-deoxy-α-d-pyranosides are more stable than exo-anomeric conformations in the gas phase. 1D NOE measurements indicate that the more polar exo-anomeric conformers are only populated to a slight extent in solution. The anti conformations are distorted so that the glycosyl substituents are closer to being eclipsed with H1. This distortion allows S n → σ* overlap if the sulfur lone pair is a p-type lone pair. Evidence for this overlap comes from short C1–S bond distances, as short as the comparable bond distances in the X-ray crystal structure and in the results from DFT calculations for the SS glycoside, which does adopt the expected exo-anomeric conformation, both in the solid state and in solution, and has normal n → σ* overlap. For 2-deoxy derivatives not bearing a 2-azido group, gas-phase DFT calculations at the same level indicate that the anti- and exo-anomeric conformers have comparable stabilities. Comparison of the results of the two series shows that electronegative substituents in equatorial orientations at C2 destabilize conformations with parallel S–O arrangements, the conformation favored by having an endocyclic C–O dipole antiparallel to the S–O dipole, by about 2.5 kcal mol–1 (1 cal = 4.184 J). An equatorial glycosyl sulfoxide, (SS) phenyl 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-1-thio-β-d-glucopyranoside S-oxide, also adopts an anti conformation in the solid state as shown by X-ray diffraction. It also adopts this conformation in solution, in contrast to studies of other equatorial glycosyl sulfoxides.
Quantitative expression analysis and study of the novel human kallikrein-related peptidase 14 gene (KLK14) in malignant and benign breast tissues
Authors: Papachristopoulou Georgia , Avgeris Margaritis , Charlaftis Antonios , Scorilas Andreas 
Published: November 2010

SummaryHuman kallikrein-related peptidase 14 gene (KLK14) is regulated by androgens and progestins. This gene is expressed in the central nervous system and endocrine tissues such as the breast, prostate and ovary. The differential KLK14 mRNA expression levels are related to several human neoplasias, among them breast cancer. The aim of this study was to analyse the KLK14 expression in breast tissues and to investigate its differential diagnostic and prognostic value in the mammary carcinomas. For this purpose, we isolated total RNA from 70 malignant and 33 benign specimens. After testing RNA quality, we synthesised cDNA by reverse transcription and applied a highly sensitive quantitative real-time PCR (qRT-PCR) method for KLK14 mRNA quantification using the SYBR Green® chemistry. HPRT1 was used as a reference gene and the BT20 breast cancer cell line as a calibrator. Relative quantification analysis was performed using the comparative CT method 2−ΔΔCT. KLK14 expression was detected in both types of breast tumours. However, a statistically significant increase of the KLK14 mRNA level was observed in the malignant, compared to the benign tumour samples (p<0.001), highlighting its value in discriminating these breast lesions. Elevated KLK14 expression profiles were associated with higher tumour grade (p=0.043) and size (p=0.007) in cancerous samples. Furthermore, KLK14 mRNA expression showed negative correlation in a statistically significant manner with estrogen receptor status (p=0.024). In accordance with logistic regression models (p=0.012) and receiver-operating-characteristics analysis (p<0.001), KLK14 gene expression could be evaluated as a putative independent diagnostic biomarker in breast tumour biopsies.
ADAMTS13 activity is decreased in a septic porcine model
Authors: Bockmeyer Clemens , Reuken Philipp , Simon Tim , Budde Ulrich , Lösche Wolfgang , Bauer Michael , Birschmann Ingvild , Becker Jan , Marx Gernot , Claus Ralf 
Published: November 2010

SummaryDuring sepsis, the balance between abundantly secreted von Wille-brand factor (VWF) and the activity of its size regulating protease ADAMTS13 is assumed to be involved in coagulation abnormalities. We aimed to establish a porcine model with haemorrhagic shock with consecutive sepsis and hypothesised that a decreased ADAMTS13-activity as well as an altered VWF multimer pattern is associated with renal failure. Animals (n=21) were subjected to haemorrhagic shock. After volume replacement, intraperitoneal Escherichia coli sepsis was induced. Blood samples were drawn at baseline, after haemorrhage and sepsis induction. Directly postmortem we examined renal tissue by JONES-silver, CD61, VWF and fibrin staining for characterisation of thrombi. Renal failure was analysed by scoring PAS-stained sections for acute tubular damage. Glomerular microthrombi were observed in six of 21 septic animals. Porcine ADAMTS13 activity declined significantly during sepsis, accompanied by a drop-off in platelet count. At 12 hours after sepsis induction, ADAMTS13 activity was significantly diminished compared to sham controls, and an elevated acute tubular damage score was associated with an increased proportion of high-molecular-weight VWF multimers. Compared to baseline the proportion of high-molecular-weight VWF multimers increased significantly in septic animals. Similar to human sepsis, diminished ADAMTS13 activity was observed in a septic porcine model associated with a shift to rather thrombogenic VWF multimers and deposition of microthrombi. Therefore, this porcine model seems to be appropriate for performing functional and therapeutic studies in sepsis-associated ADAMTS13 deficiency.
Patients with severe factor XI deficiency have a reduced incidence of deep-vein thrombosis
Authors: Salomon Ophira , Steinberg David , Zucker Michal , Varon David , Zivelin Ariella , Seligsohn Uri 
Published: November 2010

SummaryFactor XI (FXI) plays a dual role in haemostasis and thrombosis. It contributes to thrombin generation and promotes inhibition of fibrinolysis. Severe FXI deficiency was shown to confer protection against arterial and venous thrombosis in animal models without compromising haemostasis. We have previously shown that patients with severe FXI deficiency have a low incidence of ischaemic stroke, but display the usual incidence of myocardial infarction. In the present study, we compared the incidence of deep-vein thrombosis (DVT) in 219 unrelated patients with severe FXI deficiency aged 20–94 to the incidence in a large population-based study. No cases of DVT were observed in the FXI-deficient cohort, a result that is significantly lower than the expected number (4.68) computed from the population-based study. The low incidence remains statistically significant when compared to three other population-based studies. These data suggest that severe FXI deficiency provides protection against DVT.
Urban Insurgency, 'Drug War' and International Humanitarian Law: The Case of Rio de Janeiro
Authors: Peterke Sven 
Published: November 2010

AbstractIn Rio de Janeiro so-called drug factions hold control over most of the shanty towns. The State has reacted by 'militarising' its police operations. The result is a humanitarian tragedy that has already cost the lives of thousands of Brazilian citizens. Many of those affected by the violence are of the opinion that the city has become the battlefield of a 'war'. This article addresses the issue of whether the legal concept of armed conflict could and should be applied to such situations.
Austral Spring Stratospheric and Tropospheric Circulation Interannual Variability
Authors: Agosta Eduardo Andrés , Canziani Pablo Osvaldo 
Published: November 2010

AbstractThe relationship between the October (spring) total ozone column (TOC) midlatitude zonal asymmetry over the Southern Hemisphere (SH) and the stratospheric quasi-stationary wave 1 (QSW1) interannual phase variability is analyzed. Once contributions to the TOC from known global predictors, estimated with a multiregression model, are removed, the residual TOC interannual variability is observed to be dynamically coupled to the stratospheric QSW1 phase behavior. The stratospheric QSW1 interannual phase variability, when classified according to specifically designed indices, yields different circulation patterns in the troposphere and stratosphere. High (upper quartile) index values correspond to a westward rotation of the midlatitude ozone trough and the stratospheric QSW1 phase, while low (lower quartile) index values represent their eastward-rotated state. These values can be associated with statistically different tropospheric circulation patterns: a predominantly single poleward tropospheric jet structure for high index values and a predominantly double-jet structure for low index values. For the latter, there is a higher daily probability of double-jet occurrence in the troposphere and a stronger stratospheric jet. These jet structures and their daily behavior are supported by significant synoptic-scale activity anomalies over SH mid- to high latitudes as well as changes in tropospheric quasi-stationary waves 1–3. The wave activity flux (W flux) diagnosis shows the contribution of active quasi-stationary waves in the observed tropospheric anomalies associated with high and low index values. With low index values, the quasi-stationary waves lead to a self-sustaining state of the stratospheric–tropospheric coupled system. With high index values, the overall mid- to high latitude circulation is associated with wave energy propagation from the tropical central Pacific into higher latitudes. Thus, during the austral spring, there are interactions between the troposphere and stratosphere, leading to the locally well-defined upward and downward propagation of wave anomalies, that is, significant upper troposphere (UT)–lower stratosphere (LS) interactions can occur within a spring month itself.
North Pacific Decadal Variability and Climate Change in the IPCC AR4 Models
Authors: Furtado Jason C. , Di Lorenzo Emanuele , Schneider Niklas , Bond Nicholas A. 
Published: November 2010

Abstract
The two leading modes of North Pacific sea surface temperature (SST) and sea level pressure (SLP), as well as their connections to tropical variability, are explored in the 24 coupled climate models used in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) to evaluate North Pacific decadal variability (NPDV) in the past [twentieth century; climate of the twentieth century (20C3M) scenario] and future [twenty-first century; Special Report on Emissions Scenarios (SRES) A1B scenario] climate. Results indicate that the two dominant modes of North Pacific oceanic variability, the Pacific decadal oscillation (PDO) and the North Pacific Gyre Oscillation (NPGO), do not exhibit significant changes in their spatial and temporal characteristics under greenhouse warming. However, the ability of the models to capture the dynamics associated with the leading North Pacific oceanic modes, including their link to the corresponding atmospheric forcing patterns and to tropical variability, is questionable.
The temporal and spatial statistics of the North Pacific Ocean modes exhibit significant discrepancies from observations in their twentieth-century climate, most visibly for the second mode, which has significantly more low-frequency power and higher variance than in observations. The dynamical coupling between the North Pacific Ocean and atmosphere modes evident in the observations is very strong in the models for the first atmosphere–ocean coupled mode, which represents covariability of the PDO pattern with the Aleutian low (AL). However, the link for the second atmosphere–ocean coupled mode, describing covariability of an NPGO-like SST pattern with the North Pacific Oscillation (NPO), is not as clearly reproduced, with some models showing no relationship between the two.
Exploring the tropical Pacific–North Pacific teleconnections reveals more issues with the models. In contrast with observations, the atmospheric teleconnection excited by the El Niño–Southern Oscillation in the models does not project strongly on the AL–PDO coupled mode because of the displacement of the center of action of the AL in most models. Moreover, most models fail to show the observational connection between El Niño Modoki–central Pacific warming and NPO variability in the North Pacific. In fact, the atmospheric teleconnections associated with El Niño Modoki in some models have a significant projection on, and excite the AL–PDO coupled mode instead. Because of the known links between tropical Pacific variability and NPDV, these analyses demonstrate that focus on the North Pacific variability of climate models in isolation from tropical dynamics is likely to lead to an incomplete view, and inadequate prediction, of NPDV.
Evaluation of Drought Indices Based on Thermal Remote Sensing of Evapotranspiration over the Continental United States
Authors: Anderson Martha C. , Hain Christopher , Wardlow Brian , Pimstein Agustin , Mecikalski John R. , Kustas William P. 
Published: November 2010

Abstract
The reliability of standard meteorological drought indices based on measurements of precipitation is limited by the spatial distribution and quality of currently available rainfall data. Furthermore, they reflect only one component of the surface hydrologic cycle, and they cannot readily capture nonprecipitation-based moisture inputs to the land surface system (e.g., irrigation) that may temper drought impacts or variable rates of water consumption across a landscape. This study assesses the value of a new drought index based on remote sensing of evapotranspiration (ET). The evaporative stress index (ESI) quantifies anomalies in the ratio of actual to potential ET (PET), mapped using thermal band imagery from geostationary satellites. The study investigates the behavior and response time scales of the ESI through a retrospective comparison with the standardized precipitation indices and Palmer drought index suite, and with drought classifications recorded in the U.S. Drought Monitor for the 2000–09 growing seasons. Spatial and temporal correlation analyses suggest that the ESI performs similarly to short-term (up to 6 months) precipitation-based indices but can be produced at higher spatial resolution and without requiring any precipitation data. Unique behavior is observed in the ESI in regions where the evaporative flux is enhanced by moisture sources decoupled from local rainfall: for example, in areas of intense irrigation or shallow water table. Normalization by PET serves to isolate the ET signal component responding to soil moisture variability from variations due to the radiation load. This study suggests that the ESI is a useful complement to the current suite of drought indicators, with particular added value in parts of the world where rainfall data are sparse or unreliable.
Comparison of Shoulder Range of Motion, Strength, and Playing Time in Uninjured High School Baseball Pitchers Who Reside in Warm- and Cold-Weather Climates
Authors: Kaplan Kevin M. , ElAttrache Neal S. , Jobe Frank W. , Morrey Bernard F. , Kaufman Kenton R. , Hurd Wendy J. 
Published: November 2010

Background: There is an assumption that baseball athletes who reside in warm-weather climates experience larger magnitude adaptations in throwing shoulder motion and strength compared with their peers who reside in cold-weather climates. Hypotheses: (1) The warm-weather climate (WWC) group would exhibit more pronounced shoulder motion and strength adaptations than the cold-weather climate (CWC) group, and (2) the WWC group would participate in pitching activities for a greater proportion of the year than the CWC group, with the time spent pitching predicting throwing shoulder motion and strength in both groups. Study Design: Cross-sectional study; Level of evidence, 3. Methods: One hundred uninjured high school pitchers (50 each WWC, CWC) were recruited. Rotational shoulder motion and isometric strength were measured and participants reported the number of months per year they pitched. To identify differences between groups, t tests were performed; linear regression was used to determine the influence of pitching volume on shoulder motion and strength. Results: The WWC group pitched more months per year than athletes from the CWC group, with the number of months spent pitching negatively related to internal rotation motion and external rotation strength. The WWC group exhibited greater shoulder range of motion in all planes compared with the CWC group, as well as significantly lower external rotation strength and external/internal rotation strength ratios. There was no difference in internal rotation strength between groups, nor a difference in the magnitude of side-to-side differences for strength or motion measures. Conclusion: Athletes who reside in cold- and warm-weather climates exhibit differences in throwing shoulder motion and strength, related in part to the number of months spent participating in pitching activities. The amount of time spent participating in pitching activities and the magnitude of range of motion and strength adaptations in athletes who reside in warm-weather climates may make these athletes more susceptible to throwing-related injuries.
Residues at the tip of the pore loop of NR3B-containing NMDA receptors determine Ca2+ permeability and Mg2+block
Authors: Cavara Nora A , Orth Angela , Hicking Gordon , Seebohm Guiscard , Hollmann Michael 
Published: November 2010

Abstract

Background
Members of the complex N-methyl-D-aspartate receptor (NMDAR) subfamily of ionotropic glutamate receptors (iGluRs) conventionally assemble from NR1 and NR2 subunits, the composition of which determines receptor properties. Hallmark features of conventional NMDARs include the requirement for a coagonist, voltage-dependent block by Mg2+, and high permeability for Ca2+. Both Mg2+ sensitivity and Ca2+ permeability are critically dependent on the amino acids at the N and N+1 positions of NR1 and NR2. The recently discovered NR3 subunits feature an unprecedented glycine-arginine combination at those critical sites within the pore. Diheteromers assembled from NR1 and NR3 are not blocked by Mg2+ and are not permeable for Ca2+.

Results
Employing site-directed mutagenesis of receptor subunits, electrophysiological characterization of mutants in a heterologous expression system, and molecular modeling of the NMDAR pore region, we have investigated the contribution of the unusual NR3 N and N+1 site residues to the unique functional characteristics of receptors containing these subunits. Contrary to previous studies, we provide evidence that both the NR3 N and N+1 site amino acids are critically involved in mediating the unique pore properties. Ca2+ permeability could be rescued by mutating the NR3 N site glycine to the NR1-like asparagine. Voltage-dependent Mg2+ block could be established by providing an Mg2+ coordination site at either the NR3 N or N+1 positions. Conversely, "conventional" receptors assembled from NR1 and NR2 could be made Mg2+ insensitive and Ca2+ impermeable by equipping either subunit with the NR3-like glycine at their N positions, with a stronger contribution of the NR1 subunit.

Conclusions
This study sheds light on the structure-function relationship of the least characterized member of the NMDAR subfamily. Contrary to previous reports, we provide evidence for a critical functional involvement of the NR3 N and N+1 site amino acids, and propose them to be the essential determinants for the unique pore properties mediated by this subunit.
Association between different measurements of blood pressure variability by ABP monitoring and ankle-brachial index
Authors: Wittke Estefânia , Fuchs Sandra C , Fuchs Flávio D , Moreira Leila B , Ferlin Elton , Cichelero Fábio T , Moreira Carolina M , Neyeloff Jeruza , Moreira Marina B , Gus Miguel 
Published: November 2010

AbstractBackgroundBlood pressure (BP) variability has been associated with cardiovascular outcomes, but there is no consensus about the more effective method to measure it by ambulatory blood pressure monitoring (ABPM). We evaluated the association between three different methods to estimate BP variability by ABPM and the ankle brachial index (ABI).Methods and ResultsIn a cross-sectional study of patients with hypertension, BP variability was estimated by the time rate index (the first derivative of SBP over time), standard deviation (SD) of 24-hour SBP; and coefficient of variability of 24-hour SBP. ABI was measured with a doppler probe. The sample included 425 patients with a mean age of 57 ± 12 years, being 69.2% women, 26.1% current smokers and 22.1% diabetics. Abnormal ABI (≤ 0.90 or ≥ 1.40) was present in 58 patients. The time rate index was 0.516 ± 0.146 mmHg/min in patients with abnormal ABI versus 0.476 ± 0.124 mmHg/min in patients with normal ABI (P = 0.007). In a logistic regression model the time rate index was associated with ABI, regardless of age (OR = 6.9, 95% CI = 1.1- 42.1; P = 0.04). In a multiple linear regression model, adjusting for age, SBP and diabetes, the time rate index was strongly associated with ABI (P < 0.01). None of the other indexes of BP variability were associated with ABI in univariate and multivariate analyses.ConclusionTime rate index is a sensible method to measure BP variability by ABPM. Its performance for risk stratification of patients with hypertension should be explored in longitudinal studies.