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Nitrogen controls plant canopy light-use efficiency in temperate and boreal ecosystems

Optimum daily light-use efficiency (LUE) and normalized canopy photosynthesis (GEE*) rate, a proxy for LUE, have been derived from eddy covariance CO2 flux measurements obtained at a range of sites located in the mid to high latitudes. These two variables were analyzed with respect to environmental conditions, plant functional types (PFT) and leaf nitrogen concentration, in an attempt to character

Formation of Ca(BH4)(2) from hydrogenation of CaH2+MgB2 composite

The hydrogenation of the CaH2+MgB2 Composite and the dehydrogenation of the resulting products are investigated in detail by in situ time-resolved synchrotron radiation powder X-ray diffraction, high-pressure differential scanning calorimetry, infrared, and thermovolumetric measurements. It is demonstrated that a Ca(BH4)(2)+MgH2 composite is formed by hydrogenating a CaH2+MgB2 composite, at 350 de

Prognostic value of Ki-67 expression in 182 soft tissue sarcomas. Proliferation--a marker of metastasis?

Soft tissue sarcomas (STS) are characterized by deregulated proliferation. Ki-67 is a cell cycle antigen which may be elevated in proliferative states. We analysed Ki-67 expression in fixed and embedded tissues from STS in order to examine associations between proliferation, primary tumour characteristics, and metastasis. One hundred and eighty-two adult patients with trunk wall or extremity STS w

Weighted Channel Allocation and Power Control for Self-Configurable Infrastructure WLANs

IEEE802.11 WLANs show increasing growth in popularity. Since these networks operate in the unlicensed ISM bands where the number of non-overlapping channels is limited, the growing number of wireless nodes leads to interference. It is well known that the interference leads to degraded performance of WLANs, especially in densely populated areas where the number of overlapping nodes is very large. C

The association between serum sialic acid and asymptomatic carotid atherosclerosis is not related to antibodies to herpes type viruses or Chlamydia pneumoniae. The Atherosclerosis Risk in Communities (ARIC) Study Investigators

BACKGROUND: Total serum sialic acid is a recently investigated marker for cardiovascular mortality and carotid atherosclerosis. This study tested the hypothesis that past infection by Herpes simplex type 1 or type 2 viruses or Cytomegalovirus or Chlamydia pneumoniae accounts for the association between serum total sialic acid and atherosclerosis. METHODS: Population-based samples of men and women

Molecular genetic characterization of the EWS/CHN and RBP56/CHN fusion genes in extraskeletal myxoid chondrosarcoma.

Extraskeletal myxoid chondrosarcoma (EMC) is a soft-tissue neoplasm cytogenetically characterized by the translocations t(9;22)(q22;q11-12) or t(9;17)(q22;q11), generating EWS/CHN or RBP56/CHN fusion genes, respectively. In the present study, 18 EMCs were studied both cytogenetically and at the molecular level. Chromosomal aberrations were detected in 16 samples: 13 with involvement of 9q22 and 22

Estimating the total rate of DNA replication using branching processes

Increasing the knowledge of various cell cycle kinetic parameters, such as the length of the cell cycle and its different phases, is of considerable importance for several purposes including tumor diagnostics and treatment in clinical health care and a deepened understanding of tumor growth mechanisms. Of particular interest as a prognostic factor in different cancer forms is the S phase, during w

A minimal test practice framework for emerging software organizations

Testing takes a large share of software development efforts, and hence is of interest when seeking improvements. Several test process improvement frameworks exist, but they are extensive and much too large to be effective for smaller organizations. This paper presents a minimal test practice framework (MTPF) that allows the incremental introduction of appropriate practices at the appropriate time

Numerical discrimination in newborn infants as revealed by event-related potentials to tone sequences

Humans are able to attentively discriminate number from 6 months of age. However, the age of the emergence of this ability at the pre-attentive stage of processing remains unclear. Event-related potentials (ERPs) were recorded in newborn human infants aged from 3 to 5 days. At 500-ms intervals, the infants were passively exposed to 200-ms sequences of four tones. Each tone could be either 1000 or

Serum heat shock protein 70 levels predict the development of atherosclerosis in subjects with established hypertension

Although heat shock proteins (Hsp's) are present in the sera of healthy individuals and at elevated levels in subjects with early cardiovascular disease, their physiologic role in and value for predicting the development and/or progression of atherosclerosis have not been evaluated. Serum was obtained from 218 subjects with established hypertension (diastolic pressure > 95 mm Hg) before their enro

Individual and neighbourhood determinants of social participation and social capital: a multilevel analysis of the city of Malmö, Sweden.

The aim of this study was to analyse the impact of neighbourhood on individual social capital (measured as social participation). The study population consisted of 14,390 individuals aged 45-73 that participated in the Malmö diet and cancer study in 1992-1994, residing in 90 neighbourhoods of Malmö, Sweden (population 250,000). A multilevel logistic regression model, with individuals at the first

Modelling of post-irradiation events in polymer gel dosimeters

The nuclear magnetic resonance (NMR) spin-spin relaxation time (T2) is related to the radiation-dependent concentration of polymer formed in polymer gel dosimeters manufactured from monomers in an aqueous gelatin matrix. Changes in T2 with time post-irradiation have been reported in the literature but their nature is not fully understood. We investigated those changes with time after irradiation u

Propagation of very long water waves, with vorticity, over variable depth, with applications to tsunamis

We present a theory of very long waves propagating on the surface of water. The waves evolve slowly, both on the scale e (weak nonlinearity), and on the scale, a, of the depth variation. In our model, dispersion does not affect the evolution of the wave even over the large distances that tsunamis may travel. We allow a distribution of vorticity, in addition to variable depth. Our solution is not v

From proto-mimesis to language: Evidence from primatology and social neuroscience.

How can we reconcile the conception of language as a conventional-normative semiotic system with a perception/action-based account of its structure and meaning? And why should linguistic meaning - as opposed to linguistic expression - be so closely related to motor activity and its neural underpinnings, as suggested by recent findings? A conceptual framework and evolutionary scenario building on t

A representation theorem for voting with logical consequences

This paper concerns voting with logical consequences, which means that anybody voting for an alternative x should vote for the logical consequences of x as well. Similarly, the social choice set is also supposed to be closed under logical consequences. The central result of the paper is that, given a set of fairly natural conditions, the only social choice functions that satisfy social logical clo

Personality characteristics of women with fibromyalgia and of women with chronic neck, shoulder, or low back complaints in terms of Minnesota Multiphasic Personality Inventory and Defense Mechanism Technique Modified

Objectives: To compare personality features of fibromyalgia patients with those of a disease control group with regional pain. Methods: A group of 33 women with fibromyalgia [FMS-group] was compared on the Minnesota Multiphasic Personality Inventory [MMPI] and the Defense Mechanism Technique modified [DMTm] with 31 women [C-group] without this diagnosis who had localized chronic pain in their neck

Fast exponentation in cryptography

We consider the problem of minimizing the number of multiplications in computing f(x)=x n , where n is an integer and x is an element of any ring. We present new methods which reduce the average number of multiplications comparing with well-known methods, such as the binary method and the q-ary method. We do not compare our approach with algorithms based on addition chains since our approach is in

Epidemiologic and molecular investigation of outbreaks of hepatitis C virus infection on a pediatric oncology service

BACKGROUND: Despite screening of blood donors, hepatitis C virus (HCV) infection can occur in patients who receive multiple transfusions. OBJECTIVE: To clarify mechanisms of nosocomial transmission of HCV. DESIGN: Epidemiologic and molecular analyses of hepatitis C outbreaks. SETTING: Pediatric oncology ward. PATIENTS: Children with cancer. MEASUREMENTS: Epidemiologic analysis, HCV RNA detection,