Difference between heartwood and sapwood
Forest Products Laboratory (U.S.)
1919
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Electrochemical reduction of the triangular clusters [Os-3(CO)(10)(alpha-dimine)] (alpha-dimine = 2,2'-bipyridine (bpy), 2,2'-bipyrimidine (bpym)) and [Os-3(CO)(10)(mu-bpym) ReBr(CO)(3)] produces primarily the corresponding radical anions. Their stability is strongly determined by the pi acceptor ability of the reducible alpha-dimine ligand, which decreases in the order mu-bpym > bpym >> bpy. Along this series, increasing delocalisation of the odd electron density in the radical anion over the Os(alpha-dimine) chelate ring causes weakening of the axial (CO)(4)Os-Os(CO)(2)(alpha-dimine) bond and its facile cleavage for alpha-diimine = bpy. In contrast, the cluster radical anion is inherently stable for the bridging bpym ligand, the strongest pi-acceptor in the studied series. In the absence of the partial delocalisation of the unpaired ...
beta-Ureidopropionase is the third enzyme of the pyrimidine degradation pathway and it catalyses the irreversible hydrolysis of N-carbamyl-beta-aminoisobutyric acid or N-carbamyl-beta-alanine to beta-aminoisobutyric acid or beta-alanine, ammonia, and CO2. Analysis of the beta-ureidopropionase gene (UPB1) of the first 4 patients presenting with a complete enzyme deficiency, revealed the presence of 2 splice-site mutations (IVS1-2A > G and IVS8-1G > A) and one missense mutation (A85E). RT-PCR analysis of the complete beta-ureidopropionase cDNA suggested that both splice-site mutations lead to a variety of alternative splice variants, with deletions of a single or several exons. The alanine at position 85 was not conserved in other eukaryotic beta-ureidopropionase protein sequences
Objectives: Clinical trials have demonstrated that oral conjugated equine estrogen (CEE) therapy with or without medroxyprogesterone (MPA) increases venous thrombotic risk but this safety issue has not been investigated for other oral estrogens. Based on observational study findings that esterified estrogen (EE) was not associated with venous thrombotic risk whereas CEE was, we hypothesized that CEE users would be more resistant to activated protein C (APC), a prothrombotic phenotype, than EE users. Methods: We conducted an observational, cross-sectional study of postmenopausal women 30-89 years old who were controls in a case-control study of venous thrombosis. Use of CEE, EE, and MPA at the time of phlebotomy was determined using computerized pharmacy records. APC resistance was measured in plasma by the endogenous thrombin potential...
Percutaneous closure devices arc now often used for closure of the femoral puncture site after percutaneous vascular interventions. We describe a case were an accidental puncture in the aortic arch during placement of a central venous catheter is successfully closed with a closure device
The study of development and function of the immune system in vivo has made intensive use ofanimal models, but performing such work in humans is difflcultfor experimental, practical and ethical reasons. Conftonted with this scientific challenge, several pioneering groups have developed in the late 1980s mouse models ofhuman immune system development. Although these experimental approaches were proven successful and useful they were sufferingftom limitations due to xenograft transplantation barriers. By reviewing the characteristics of the successive model over the last 20 years, it becomes apparent that screening ofpotentially interesting mouse strains and usage of combinations of genetic deficiencies has led to major advances. This is particularly true for human T cell development in the murine thymus. This review will focus on these ...
Background: Impairments in decision making are a consistent finding in substance use disorder (SUD) populations. However, decision-making deficits are not specific for SUDs and are also reported in the context of other psychiatric disorders such as antisocial and borderline personality disorders (PDs). Given the frequent comorbidity between SUD and cluster B PD, it might be questioned whether the decision-making impairments typically reported in SUD populations reflect the addictive disorder, the cluster B PD, or a combination of the 2. Methods: In the current study, we compare the decision-making performance of non-substance-abusing controls (n=53) on the Iowa Gambling Task (IGT) with the decision-making performance of 3 abstinent alcohol-dependent samples, i.e., alcoholic patients without any PD (n=38), alcoholic patients with a clus...


