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Effects of ultraviolet-B radiation and pH on early development of the moor frog Rana arvalis

Although the potential negative effects of increased ultraviolet-B (UV-B) radiation on early life stages of aquatic organisms are widely recognized, possible synergistic effects with other stressors have seldom been studied outside the laboratory. We investigated the effects of UV-B radiation and pH on hatchability and early development of moor frog Rana arvalis eggs in the field and in laboratory

Plasma prolactin in relation to menstrual cycle phase, oral contraceptive use, arousal time and smoking habits

The study was designed to investigate if modern low dosage combined oral contraceptives were associated with changes in plasma prolactin levels in healthy nulliparous women aged 19-25. Plasma prolactin was not significantly correlated to oral contraceptive use, nor to smoking habits. Plasma prolactin was, however, significantly negatively correlated to time since awakening. A significant two-way i

Sequence variations in the DNA repair gene XPD and risk of lung cancer in a Chinese population.

Variation in DNA repair capacity, which is believed to be largely determined by genetic traits, is linked to risk of certain cancers. The Asp312Asn and Lys751Gln polymorphisms in the xeroderma pigmentosum complementary group D (XPD) gene may alter DNA repair capacity. We thus examined the hypothesis that these 2 XPD polymorphisms are associated with risk of lung cancer via a large hospital-based,

TIMESAT - a program for analyzing time-series of satellite sensor data

Three different least-squares methods for processing time-series of satellite sensor data are presented. The first method uses local polynomial functions and can be classified as an adaptive Savitzky-Golay filter. The other two methods are more clear cut least-squares methods, where data are fit to a basis of harmonic functions and asymmetric Gaussian functions, respectively. The methods incorpora

DNA encapsulation by biocompatible catanionic vesicles

The encapsulation of DNA by catanionic vesicles has been investigated; the vesicles are composed of one cationic surfactant, in excess, and one anionic. Since cationic systems are often toxic, we introduced a novel divalent cationic amino-acid-based amphiphile, which may enhance transfection and appears to be nontoxic, in our catanionic vesicle mixtures. The cationic amphiphile is arginine-N-lauro

Angle-resolved photoion yield and resonant Auger spectroscopy for the doubly excited Rydberg states above the C 1s threshold of CO

Doubly excited core-hole states of carbon monoxide in the photon energy region of 300-305 eV, i.e., directly above the C 1s ionization threshold, have been studied using both angle-resolved ion-yield and high-resolution resonant Auger spectroscopies. The leading configurations of the most prominent doubly excited Rydberg states are assigned by careful analysis of the ion-yield spectra and the fina

Ficoll and dextran vs. globular proteins as probes for testing glomerular permselectivity: effects of molecular size, shape, charge, and deformability.

Polydisperse mixtures of dextran or Ficoll have been frequently used as molecular probes for studies of glomerular permselectivity because they are largely inert and not processed (reabsorbed) by the proximal tubules. However, dextrans are linear, flexible molecules, which apparently are hyperpermeable across the glomerular barrier. By contrast, the Ficoll molecule is almost spherical. Still, ther

Gauge fields, point interactions and few-body problems in one dimension

Point interactions for the second derivative operator in one dimension are studied. Every operator from this family is described by the boundary conditions which include a 2 x 2 real matrix with the unit determinant and a phase. The role of the phase parameter leading to unitarily equivalent operators is discussed in the present paper. In particular, it is shown that the phase parameter is not red

Cross layer routing and media access control with channel dependant forwarding in wireless ad-hoc networks

Wireless ad hoc networks have the last 10 years gained a lot of attention within the research community. A wireless ad hoc network is a special type of wireless network where nodes are typically mobile and doesn’t rely on any fixed infrastructure to operate correctly. Much work has been done on developing robust and stable routing algorithms that consider the dynamic nature of an ad hoc network: n

Transfection of HeLa-cells with pEGFP plasmid power-assisted by impedance electroporation

Bioimpedance spectrometry was applied to study cell viability and pEGFP plasmid-transfection efficiency in electroporation (EP) of 20,000 HeLa cells with 0.3 mu g DNA in 90 mu l low conductivity 0.32 M sucrose medium of pH 7.5. Monopolar rectangular pulses, of field strength 75 V/mm, and pulse length 0.1 ms were applied in 1-16 repetitions with a 10-sec pause interval between pulses. Surviving cel

LES of supersonic combustion in a scramjet engine model

In this study, Large Eddy Simulation (LES) has been used to examine supersonic flow and combustion in a model scramjet combustor. The LES model is based on an unstructured finite volume discretization, using total variational diminishing flux reconstruction, of the filtered continuity, momentum, enthalpy, and passive/reactive scalar equations, used to describe the combustion process. The configura

CSF Biomarkers for Alzheimer's Disease: Levels of beta-Amyloid, Tau, Phosphorylated Tau Relate to Clinical Symptoms and Survival.

Cerebrospinal fluid (CSF) samples from 21 patients with a clinical diagnosis of Alzheimer's disease (AD) participating in a 5-year treatment study with the choline esterase inhibitor tacrin were retrospectively analyzed for the contents of beta-amyloid (Abeta42), total tau (T-tau) and phosphorylated tau (P-tau). A significant positive correlation between the level of P-tau and the number of sympto

Dopamine released from 5-HT terminals is the cause of L-DOPA-induced dyskinesia in parkinsonian rats.

n patients with Parkinson's disease, the therapeutic efficacy of L-DOPA medication is gradually lost over time, and abnormal involuntary movements, dyskinesias, gradually emerge as a prominent side-effect in response to previously beneficial doses of the drug. Here we show that dyskinesia induced by chronic L-DOPA treatment in rats with 6-hydroxydopamine-induced lesions of the nigrostriatal dopami

Alveolar accumulation of fibronectin and hyaluronan precedes bleomycin-induced pulmonary fibrosis in the rat

The development of bleomycin-induced pulmonary fibrosis in rats was studied over a period of 30 days after an intratracheal instillation of bleomycin. Fibronectin was visualized in histological sections and quantified in bronchoalveolar lavage fluid (BALF) and related to simultaneous measurements of hyaluronan, collagen and albumin in BALF and/or lung tissue extracts. An increase in BALF fibronect

Modeling of protein breakthrough performance in cryogel columns by taking into account the overall axial dispersion.

A model considering the overall axial dispersion for describing protein adsorption and breakthrough in monolithic cryogel beds has been developed. The microstructure of cryogels was characterized by tortuous capillaries with a normal diameter distribution but a constant pore wall thickness. The axial dispersion within cryogel columns was described by using the overall axial dispersion coefficient,

Desmin filaments influence myofilament spacing and lateral compliance of slow skeletal muscle fibres.

Intermediate filaments composed of desmin interlink Z-disks and sarcolemma in skeletal muscle. Depletion of desmin results in lower active stress of smooth, cardiac, and skeletal muscles. Structural functions of intermediate filaments in fast (psoas) and slow (soleus) skeletal muscle were examined using x-ray diffraction on permeabilized muscle from desmin-deficient mice (Des–/–) and controls (Des

Synthesis, structure, and reactivity of arylfluoro platinum(II) complexes.

Complexes of the type trans-[PtPhFL2], where L = PPh3 (4), PMe2Ph (5), were synthesized. Complex 4 was characterized by X-ray crystallography. The equilibrium constant for the substitution of the fluoride trans to phenyl in 4 by Cl- and I- was determined, and the stability sequence follows the normal trend seen in "soft" metal centers: i.e., the Pt has a preference for the halide in the order I >

Post-juvenile and post-breeding moult of Savi’s Warblers Locustella luscinioides in Portugal.

We describe the sequence and extent of the complex and little understood post-juvenile and post-breeding moults of Savi’s Warblers Locustella luscinioides. In contrast to previous studies, the post-juvenile moult occurred in at least 44% of the birds, 5% of which moulted some or all tertials and greater coverts. The timing of overlap between the filling and the post-juvenile moults, and the fact t

Tobacco peroxidase as a new reagent for amperometric biosensors

The results of testing a new enzyme, anionic tobacco peroxidase (TOP), in various amperometric biosensors are summarized. The biochemical and electrochemical properties of the enzyme are briefly characterized. As compared to the commonly used cationic peroxidase from horseradish roots, TOP exhibits a wider optimum stability pH range, higher stability to inactivation with hydrogen peroxide, and hig