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Tertiary phosphine abstraction from a platinum(II) coordination complex with SeCN-: Crystal and molecular structures of Se=PTA and [Se=PTA-Me]I center dot CH3OH

Reacting [PtCl(PTA)(3)]Cl (PTA = 1,3,5-triaza-7-phosphatricyclo[3.3.1.1(3,7)]decane) with KSeCN in aqueous or MeOH medium results in the abstraction of the PTA ligands to yield Se = PTA. The reaction also proceeds quantitatively by direct reaction of PTA and KSeCN in water or methanol. The methylated PTA ligand, [PTA-Me]I (1-methyl-1-azonia-3,5-diaza-7-phosphatricyclo[3.3. 1.1(3,7)]decane iodide),

A probabilistic approach to the use of pollen indicators for plant attributes and biomes: an application to European vegetation at 0 and 6 ka

Aim This paper presents a probabilistic method for the characterization of pollen taxa using attributes, and for the reconstitution of past biomes. The probabilities are calculated on the basis of European floristic and pollen databases sufficiently large and exhaustive to provide robust estimates. Location The analysis is based on data from approximately 1000 sites throughout Europe. Method We us

Variability in muscle fibre areas in whole human quadriceps muscle. How much and why?

To determine the variability in fibre areas in the human vastus lateralis muscle, cross-sections (15 microns) of whole autopsied muscles from eight young men have been prepared, and the cross-sectional area (CSA) of 375 type 1 and 375 type 2 fibres has been measured in five different regions throughout each muscle. The CSA of both fibre types varied significantly within all muscle cross-sections.

Operator-centred local error management in air traffic control

Introduction: A large number of air traffic control occurrences take place without resulting in loss of separation between aircraft. Unfortunately such occurrences are seldom reported and therefore not used for disclosing system weaknesses, Such as inappropriate methods and procedures. The ATCC (Air Traffic Control Centre) Malmoe made a trial with local reporting of "learning occurrences". The tri

Different roles for non-receptor tyrosine kinases in arachidonate release induced by zymosan and Staphylococcus aureus in macrophages

BACKGROUND: Yeast and bacteria elicit arachidonate release in macrophages, leading to the formation of leukotrienes and prostaglandins, important mediators of inflammation. Receptors recognising various microbes have been identified, but the signalling pathways are not entirely understood. Cytosolic phospholipase A2 is a major down-stream target and this enzyme is regulated by both phosphorylation

Pseudoscalar meson mass to two loops in three-flavor partially quenched chiral perturbation theory

This paper presents a first study of the pseudoscalar meson masses to two loops, or next-to-next-to-leading order, within the supersymmetric formulation of partially quenched chiral perturbation theory (PQchiPT). The expression for the pseudoscalar meson mass in the case of three valence and three sea quarks with equal masses, but different from each other, is given to O(p(6)), along with a numeri

Discrimination between Patients with Acoustic Neuroma and with Peripheral Vestibular Lesion by Human Posture Dynamics

A group of normal subjects (n = 17) was compared with two groups of patients, either with vestibular neuritis (n = 18) or with acoustic neuroma (n = 35) by means of posturography when stance was perturbed with vibrators attached to the calf muscles. Dynamic control of human posture was quantified by means of system identification, and the characteristic parameters of swiftness, stiffness, and damp

A comparison of structural and mechanical properties in cancellous bone from the femoral head and acetabulum

Mechanical interlock obtained by penetration of bone cement into cancellous bone is critical to the success of cemented total hip replacement (THR). Although acetabular component loosening is an important mode of THR failure, the properties of acetabular cancellous bone relevant to cement penetration are not well characterized. Bone biopsies (9 mm diameter, 10 mm long) were taken from the articula

CD133 is not present on neurogenic astrocytes in the adult subventricular zone, but on embryonic neural stem cells, ependymal cells, and glioblastoma cells

Human brain tumor stem cells have been enriched using antibodies against the surface protein CD133. An antibody recognizing CD133 also served to isolate normal neural stem cells from fetal human brain, suggesting a possible lineage relationship between normal neural and brain tumor stem cells. Whether CD133-positive brain tumor stem cells can be derived from CD133-positive neural stem or progenito

Interplay Between an AAA Module and an Integrin I Domain May Regulate the Function of Magnesium Chelatase

In chlorophyll biosynthesis, insertion of Mg2+ into protoporphyrin IX is catalysed in an ATP-dependent reaction by a three-subunit (BchI, BchD and BchH) enzyme magnesium chelatase. In this work we present the three-dimensional structure of the ATP-binding subunit BchI. The structure has been solved by the multiple wavelength anomalous dispersion method and refined at 2.1 A resolution to the crysta

Varför bildas nya partier? : Om kollektivt handlande och partientreprenörer

Popular Abstract in Swedish Eftersom politiska partier är kollektiva varor står potentiella partibildare inför det kollektiva handlandets problem. Därför kan vi tala om en "partibildningsparadox". Sålunda är det förvånande att icke riksdagsetablerade partier blev vanligare förekommande i svenska kommuner mellan 1973 och 2002. Utvecklingen ger oss ett unikt material på vilket vi kan pröva hypoteserSince political parties are collective goods, groups of people that demand new political parties face a collective action problem. Therefore, we can speak of a ?paradox of party-emergence?. Hence, it is puzzling that new parties became increasingly common in representative bodies at the Swedish local level during 1973?2002. This development provides a unique circumstance on which to test hypothese

Results of second-look resection after primary resection of T1 tumour of the urinary bladder

Objective. To study residual tumours at second-look resection in patients resected 4-8 weeks earlier for T1 tumours of the urinary bladder. Material and methods. All patients randomized in the ongoing Nordic T1G2-G3 Bladder Sparing Study with monitored data available were included in the study. Data on residual tumours at second-look resection were compared to basic patient and tumour characterist

Interference elimination in glutamate monitoring with chip integrated enzyme microreactors

On-chip enzyme reactors are often used in medical/pharmaceutical analysis due to their inherent advantages, such as high sample throughput, low reagent consumption, stability, reproducibility and low cost. The present work describes a different application of such microreactors, namely, elimination of interfering ascorbate signals in glutamate monitoring using ascorbate oxidase modified silicon ch

Microorganisms and volatile organic compounds in airborne dust from damp residences

Airborne dust samples from damp (n = 9) and control (n = 9) residences were analyzed for microorganisms (molds and bacteria), bacterial markers (3-hydroxy fatty acids and muramic acid), and adsorbed volatile organic compounds (VOCs). The number of mold species was greater in the damp residences than in the controls (23 vs.18) and nine mold species were found only in damp residences. The levels of

Screening the molecular surface of human anticoagulant protein C: a search for interaction sites

Protein C (PC), a 62 kDa multi-modular zymogen, is activated to an anticoagulant serine protease (activated PC or APC) by thrombin bound to thrombomodulin on the surface of endothelial cells. PC/APC interacts with many proteins and the characterisation of these interactions is not trivial. However, molecular modelling methods help to study these complex biological processes and provide basis for r

Note on covering monotone orthogonal polygons with star-shaped polygons

In 1986, Keil provided an O(n(2)) time algorithm for the problem of covering monotone orthogonal polygons with the minimum number of r-star-shaped orthogonal polygons. This was later improved to O(n) time and space by Gewali et al. in [L. Gewali, M. Keil, S.C. Ntafos, On covering orthogonal polygons with star-shaped polygons, Information Sciences 65 (1992) 45-63]. In this paper we simplify the lat

New and improved experimental oscillator strengths in ZrII and the solar abundance of zirconium

Using the Fourier Transform Spectrometer at Lund Observatory, intensity calibrated spectra of singly ionized zirconium have been recorded and analyzed. Oscillator strengths for 263 Zr II spectral lines in the region 2500-5400 angstrom have been derived by combining new experimental branching fractions with previously measured radiative lifetimes. The transitions combine 34 odd parity levels with 2