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Abstract in UndeterminedSoil microbes constitute an important control on nitrogen (N) turnover and retention in arctic ecosystems where N availability is the main constraint on primary production. Ectomycorrhizal (ECM) symbioses may facilitate plant competition for the specific N pools available in various arctic ecosystems. We report here our study on the N uptake patterns of coexisting plants an

Rat adipocyte cGMP-inhibited cAMP phosphodiesterase (cGI-PDE) appears to be dually regulated in intact cells by serine phosphorylations induced by isoprenaline and insulin, respectively (Degerman, E., Smith, C. J., Tornqvist, H., Vasta, V., Belfrage, P., and Manganiello, V. C. (1990) Proc. Natl. Acad. Sci. U.S.A. 87, 533-537; Smith, C. J., Vasta, V., Degerman, E., Belfrage, P., and Manganiello, V.

Leukotriene ( LT) A(4) hydrolase is a bifunctional zinc metalloenzyme, which converts LTA(4) into the neutrophil chemoattractant LTB4 and also exhibits an anion-dependent aminopeptidase activity. In the x-ray crystal structure of LTA(4) hydrolase, Arg(563) and Lys(565) are found at the entrance of the active center. Here we report that replacement of Arg(563), but not Lys(565), leads to complete a

Accurate detection of cancer-associated molecular abnormalities in tumors could make cancer treatment more personalized. Affibody molecules enable high contrast imaging of tumor-associated protein expression shortly after injection. The use of the generator-produced positron-emitting radionuclide (68)Ga should increase sensitivity of HER2 imaging. The chemical nature of radionuclides and chelators

Reaction of the new asymmetric ligand 2-(N-isopropyl-N-((1-methylimidazolyl)methyl)aminomethyl)-6-(N-carboxylm ethyl-N-((1-methylimidazolyl)methyl) aminomethyl)-4-methylphenol (ICIMP) with nickel perchlorate and diphenylacetic acid leads to the formation of tetranuclear nickel complexes, whose crystal structures reveal that they consist of dimers of dimers in which each Ni-2 unit has a coordinatio

Prospective cohort studies about cutaneous melanoma (CM) risk are still few. Host factor- and UVR exposure data were collected prospectively by questionnaire in this population-based cohort study including 40000 Swedish born women, aged 25-64 years at enrolment (1990). Risk for CM (Cox regression and Stepwise Cox regression [SCR], hazard ratios [HRs] with 95 % Confidence Intervals [CI]) in relatio

Ribonucleotide reductases (RNRs) catalyze the reduction of ribonucleotides to deoxyribonucleotides, the building blocks for DNA synthesis, and are found in all but a few organisms. RNRs use radical chemistry to catalyze the reduction reaction. Despite RNR having evolved several mechanisms for generation of different kinds of essential radicals across a large evolutionary time frame, this initial r

Pharmaceutical residues discharged through insufficiently treated or untreated wastewater enter aquatic environments, where they may adversely impact organisms such as aquatic invertebrates. Ozonation, an advanced wastewater treatment technique, has been successfully implemented to enhance the removal of a broad range of pharmaceuticals, however diverse byproducts and transformation products that

Expansion of extracellular matrix occurs in all stages of pulmonary angiopathy associated with pulmonary arterial hypertension (PAH). In systemic arteries, dysregulation and accumulation of the large chondroitin-sulfate proteoglycan aggrecan is associated with swelling and disruption of vessel wall homeostasis. Whether aggrecan is present in pulmonary arteries, and its potential roles in PAH, has

Secondary organic aerosol (SOA) plays a significant role in climate change by altering the global atmospheric radiation budget. Biogenic volatile organic compounds (BVOCs) are major sources for the formation of SOA. Their relationship is critical to understand the continental biosphere-aerosol-cloud-climate (COBACC) feedback mechanism but receives less attention in previous studies. In this study,

Low-energy-electron-diffraction (LEED), scanning-tunneling-microscopy (STM), and photoelectron-spectroscopy measurements have been performed on the ordered submonolayer surface reconstructions of Yb on Si(111). Two of these reconstructions, namely, 3×1 and 2×1, have been studied in detail. STM and LEED revealed that what was considered to be the 3×1 reconstruction is actually a 3×2 reconstruction.