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Transcriptional dynamics of the embryonic stem cell switch

Recent ChIP experiments of human and mouse embryonic stem cells have elucidated the architecture of the transcriptional regulatory circuitry responsible for cell determination, which involves the transcription factors OCT4, SOX2, and NANOG. In addition to regulating each other through feedback loops, these genes also regulate downstream target genes involved in the maintenance and differentiation

Centrality dependence of pi(0) and eta production at large transverse momentum in root s(NN) = 200 GeV d+Au collisions

The dependence of transverse momentum spectra of neutral pions and eta mesons with p(T) < 16 GeV/c and p(T) < 12 GeV/c, respectively, on the centrality of the collision has been measured at midrapidity by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider (RHIC) in d + Au collisions at root s(NN) = 200 GeV. The measured yields are compared to those in p + p collisions at the same roo

Guidelines for radioiodine therapy of differentiated thyroid cancer

Introduction The purpose of the present guidelines on the radioiodine therapy (RAIT) of differentiated thyroid cancer (DTC) formulated by the European Association of Nuclear Medicine (EANM) Therapy Committee is to provide advice to nuclear medicine clinicians and other members of the DTC-treating community on how to ablate thyroid remnant or treat inoperable advanced DTC or both employing large 13

Prediction of patient outcome with 2-deoxy-2-[18F]fluoro-D-glucose-positron emission tomography early during radiotherapy for locally advanced cervical cancer.

INTRODUCTION: It is difficult to assess the individual response of locally advanced cervical cancer to chemoradiation therapy during the course of treatment. We have investigated the predictive value of positron emission tomography (PET) with 2-deoxy-2-[18F]fluoro-D-glucose (FDG) early during treatment in relation to progression-free survival. METHODS: This prospective single-center clinical trial

Extending EDCA with Distributed Resource Reservation for QoS Guarantees

In this paper we describe how the contention-based medium access mechanism of 802.11e, EDCA, can be enhanced in order to allow stations to reserve medium access for their real-time applications with QoS requirements. We present our proposed scheme, which is called EDCA with resource reservation (EDCA/RR), and describe how it can be extended in order to be used in wireless multi-hop networks. EDCA/

The discrete nature of the growth and arrest of microstructurally short fatigue cracks modelled by dislocation technique

Growth of a microstructurally short edge crack in the neighbourhood of a grain boundary has been studied using a dislocation technique. Influence of the distance between the crack tip and a high-angle grain boundary was studied for 5000 load cycles. Growth rate was found to change stepwise during crack advance, both accelerating and decelerating, and finally retarding before crack arrest. Crack pr

Heat stress alters G-protein coupled receptor-mediated function and endothelium-dependent relaxation in rat mesenteric artery

Heat stress has been demonstrated to have strong cardiovascular effects. However, the underlying mechanism-mediated cardiovascular effects are still not fully understood. The present study was designed to examine if heat stress alters vascular G-protein coupled receptor-mediated vasomotion and endothelium function in rat mesenteric artery. Rats were divided into two groups, heat stress rats and co

Evidence of stress-induced hydrogen ordering in zirconium hydrides

The formation of hydrides in zirconium alloys significantly affects their mechanical properties and is considered to play a critical role in their failure mechanisms, yet relatively little is known about the micromechanical behavior of hydrides in the bulk. This paper presents the result of in situ uniaxial mechanical tensioning experiments on hydrided zircaloy-2 and zircaloy-4 specimens using ene

Suramin selectively inhibits carcinoma cell growth that is dependent on extracellular polyamines.

Polyamines are necessary for tumour cell growth. Inhibition of endogenous polyamine biosynthesis results in compensatory up-regulation of polyamine uptake. Here, the combined effect of suramin and the polyamine biosynthesis inhibitor alpha-difluoromethylornithine (DFMO) on human carcinoma cell proliferation was studied. Suramin selectively inhibited the growth of tumour cells made dependent on ext

The notion of "phonology' in dyslexia research: Cognitivism - and beyond

Phonology has been a central concept in the scientific study of dyslexia over the past decades. Despite its central position, however, it is a concept with no precise definition or status. The present article investigates the notion of 'phonology' in the tradition of cognitive psychology. An attempt is made to characterize the basic assumptions of the phonological approach to dyslexia and to evalu

Fecundability according to male serum inhibin B - a prospective study among first pregnancy planners

BACKGROUND: New biological markers of male fecundity are needed for use in large-scale epidemiological studies. We studied the association between male inhibin B and fecundability. METHODS: Four hundred and thirty Danish couples without previous reproductive experience were followed from termination of contraception until pregnancy or for a maximum of six menstrual cycles. At enrolment we obtained

Ultrasonic agitation in microchannels

This paper describes an acoustic method for inducing rotating vortex flows in microchannels. An ultrasonic crystal is used to create an acoustic standing wave field in the channel and thus induce a Rayleigh flow transverse to the laminar flow in the channel. Mixing in microchannels is strictly diffusion-limited because of the laminar flow, a transverse flow will greatly enhance mixing of the react

Diode laser absorption spectroscopy for studies of gas exchange in fruits

Gas exchange in fruits, in particular oxygen transport in apples, was studied non-intrusively using wavelength modulation diode laser absorption spectroscopy at about 761 run, applied to the strongly scattering intact fruit structure. The applicability of the technique was demonstrated by studies of the influence of the skin to regulate the internal oxygen balance and of cling film in modifying it

CYP gene polymorphisms and early menarche

Early age at menarche is a risk factor for breast cancer. A previous study reported a significant positive association between the CYP3A4*1B variant allele and early puberty. We investigated whether polymorphisms of the CYP3A4, CYP17, CYP1B1, and CYP1A2 genes predict the age at onset of menarche. Five hundred eighty-three nulliparous women between ages 17 and 35, of various ethnic backgrounds, com

A Swedish prevalence study of deaf people using sign language: a prerequisite for deaf studies

A widely used estimate claims that one per thousand individuals is deaf, but few recent studies exist on the actual prevalence. The aim of this study was to investigate the prevalence of deaf people, defined as deaf individuals who use sign language as their main mode of communication, in the county of Scania, Sweden. To achieve high validity, data were collected from a large variety of sources in

Nerve induced responses and force-velocity relations of regenerated detrusor muscle after subtotal cystectomy in the rat.

AIMS: To study the pharmacological and mechanical properties of newly developed detrusor muscle after subtotal cystectomy, to explore if the regenerated detrusor has characteristics similar to the normal bladder base, from which it regenerated, or to the normal bladder body which it replaces. METHODS: Partial cystectomy was performed in female rats. Fifteen weeks later, detrusor strips were cut fr

Tyrosinase-mediated formation of a reactive quinone from the depigmenting agents, 4-tert-butylphenol and 4-tert-butylcatechol

Exposure of the skin to certain phenols or catechols such as 4-tert-butylphenol (TBP) and 4-tert-butylcatechol (TBC) may cause leukoderma. These substances are used in the polymer industry and numerous cases have been reported. Several theories of the mechanism for chemical leukoderma have been suggested. In the present study, TBP and TBC are shown to be oxidised by tyrosinase. The oxidation of TB

Follow-up of pituitary tumor volume in patients with acromegaly treated with pegvisomant in clinical trials

Objective: We examined pituitary tumor volumes in patients treated with pegvisomant for 18 months or longer and in whom the tumors were monitored for at least 3 years. We present details on 9 of 304 patients in clinical trials with pegvisomant who experienced tumor growth within the first year of treatment. Method: Magnetic reonance images prior to start of pegvisomant and at last follow-up were e

Homeward bound: Introducing a four-domain model of perceived housing in very old age

The aim of this article is to introduce an integrative and more comprehensive approach to understanding and measuring perceived housing in old age. First, four conceptual domains of subjective housing were introduced, based on the assumption that each of the domains brings a unique perspective to the understanding of perceived housing: housing satisfaction, usability in the home, meaning of home a