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NMR structure determination of proteins supplemented by quantum chemical calculations: Detailed structure of the Ca2+ sites in the EGF34 fragment of protein S

We present and test two methods to use quantum chemical calculations to improve standard protein structure refinement by molecular dynamics simulations restrained to experimental NMR data. In the first, we replace the molecular mechanics force field ( employed in standard refinement to supplement experimental data) for a site of interest by quantum chemical calculations. This way, we obtain an acc

Tritrophic interactions in a soil community enhance decomposition rates

Microbivorous soil fauna can influence decomposition rates by regulating biomass and composition of the microbial community. The idea that predators at higher trophic levels regulate population densities of microbivorous fauna and thus indirectly increase microbial growth and activity has often been suggested but rarely examined in soil ecosystems. In this paper the effects of tritrophic interacti

Economic evaluation of the hydrolysis of lactose using immobilized beta-galactosidase

A computer program for preliminary cost estimates of free and immobilized enzyme systems has been developed. The cost for the hydrolysis of lactose by β-galactosidase fromAspergillus oryzae has been calculated for a batch tank reactor, with free (BTRF) and immobilized (BTRI) enzymes, a continuously stirred tank reactor (CSTR) and a plug-flow tubular reactor (PFTR), considering the mass transfer be

Artificially controlled aggregation of proteins and targeting in hematopoietic cells

The targeting mechanisms for granule proteins in hematopoietic cells are largely unknown. Aggregation is believed to be important for protein sorting-for-entry and sorting-by-retention in endocrine and neuroendocrine cells. We asked whether artificially induced multimerization/aggregation of chimeric proteins could affect their sorting in hematopoietic cells. A system was used that permits ligand-

Long-distance pollen flow assessment through evaluation of pollinator foraging range suggests transgene escape distances

Foraging range, an important component of bee ecology, is of considerable interest for insect-pollinated plants because it determines the potential for outcrossing among individuals. However, long-distance pollen flow is difficuit to assess, especially when the plant also relies on self-pollination. Pollen movement can be estimated indirectly through population genetic data, but complementary data

The BRCA1 syndrome and other inherited breast or breast-ovarian cancers in a Norwegian prospective series

Inherited breast cancer is a heterogenous group of diseases. We examined this heterogeneity in a prospective series of inherited breast and ovarian cancers, previously demonstrated to include 84% of inherited cancers. Ninety-two tumours (65 breast and 27 ovarian) in 82 patients from 70 kindreds were prospectively diagnosed. Fifteen of the breast cancers were in situ, 50 were infiltrating. 40 (49%)

Investigation of turbulence models applied to premixed combustion using a level-set flamelet library approach

Most of the common modeling approaches to premixed combustion in engineering applications are either based on the assumption of infinitely fast chemistry or the flamelet assumption with simple chemistry. The level-set flamelet library approach (FLA) has shown great potential in predicting major species and heat release, as well as intermediate and minor species, where more simple models often fail

Human death--a view from the beginning of life.

This paper presents a simple argument against definitions of the death of a human being in terms of death, or the cessation of functioning, of its brain: a human being is alive, and is capable of dying, before it acquires a brain. Although a more accurate definition is sketched, it is stressed that it should not be taken for granted that it is ethically urgent to work out such a definition. What m

On the construction of perfect authentication codes that permit arbitration

Authentication codes that permit arbitration are codes that unconditionally protect against deceptions from the outsiders and additionally also protect against some forms of deceptions from the insiders. Simmons introduced this authentication model and he also showed a way of constructing such codes, called the Cartesian product construction. We present a general way of constructing such codes and

Velocities for moving random surfaces

For a stationary two-dimensional random field evolving in time, we derive statistical distributions of appropriately defined velocities. The results are based on a generalization of the Rice formula. We discuss importance of identifying the correct form of the distribution which accounts for the sampling bias. The theory can be applied to practical problems where evolving random fields are conside

Molecular analysis of a Saccharomyces cerevisiae mutant with improved ability to utilize xylose shows enhanced expression of proteins involved in transport, initial xylose metabolism, and the pentose phosphate pathway.

Differences between the recombinant xylose-utilizing Saccharomyces cerevisiae strain TMB 3399 and the mutant strain TMB 3400, derived from TMB 3399 and displaying improved ability to utilize xylose, were investigated by using genome-wide expression analysis, physiological characterization, and biochemical assays. Samples for analysis were withdrawn from chemostat cultures. The characteristics of S

Clinicopathologic re-evaluation of 100 malignant fibrous histiocytomas: prognostic relevance of subclassification

PURPOSE: Malignant fibrous histiocytoma (MFH) has been regarded as the most common soft tissue sarcoma (STS) in adults. Yet its true nature and the validity of this diagnostic concept have increasingly been questioned. Available data suggest that most patients with MFH can be subclassified into specific STS types, but the clinical relevance of such categorization has been argued. In a retrospectiv

Toll-like receptors in cellular subsets of human tonsil T cells: altered expression during recurrent tonsillitis

Background: The palatine tonsils have a pivotal role in immunological detection of airborne and ingested antigens like bacteria and viruses. They have recently been demonstrated to express Toll-like receptors ( TLRs), known to recognize molecular structures on such microbes and activate innate immune responses. Their activation might also provide a link between innate and adaptive immunity. In the

Novel genetic variant in FTO influences insulin levels and insulin resistance in severely obese children and adolescents

Background: The global prevalence of obesity and overweight is increasing rapidly among adults as well as among children and adolescents. Recent genome-wide association studies have provided strong support for association between variants in the FTO gene and obesity. We sequenced regions of the FTO gene to identify novel variants that are associated with obesity and related metabolic traits. Resul

Personality and marital satisfaction: A behavioural genetic analysis

Previous research has found that genetic and nonshared environmental factors influence Marital quality (Spotts et al., 2004). The current study explored personality as a source for these genetic and environmental individual differences. A sample of 752 Swedish twin women and their spouses were used. Genetic and environmental influences were found for self-report measures of Marital quality, but on