687 research outputs found
Electroweak Interactions: Experimental Facts and Theoretical Foundation
Although intimate partner violence (IPV) is an important problem that threatens women’s health, very few studies focus on the victim—perpetrator relationship or examine this relationship across Turkey. The aim of this study is to contribute to a better understanding of femicide cases in Turkey and to describe the socio-demographic, clinical, forensic, and criminological characteristics of femicide victims and offenders. This study analysed 162 femicide cases that occurred in 12 cities in Turkey from 1 January 2000 to 31 December 2010. Eighty women were killed by their partners (classified as intimate partner femicide, IPF), and 81 women were killed by one of their relatives, friends, or strangers (classified as non-intimate partner femicide, non-IPF). According to our results, the typical IPF victim is of child-bearing age, does not have a paid job, is married or divorced, is killed in a domestic setting due to injuries to the thorax or abdomen produced by an edged/pointed weapon or firearm, and is possibly a victim of overkill. The typical IPF perpetrator is close to his victim’s age, has a paid job, has no mental disability, owns a gun, and has threatened his partner or ex-partner previously because of jealousy/infidelity/honour or separation. The typical non-IPF victim is very similar to the IPF victim; however, her marital status can be single, married or divorced, and she is commonly killed by a relative. The surveillance and screening of femicide and IPV is an important step when analysing and attempting to prevent femicide. Second, the training and sensitization of health professionals are important. Moreover, health staff should be encouraged to participate in advocacy interventions. Third, gun ownership must be brought under control. © 2017 Toprak, Ersoy. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
POSTERIORI PROBABILITY ESTIMATION AND PATTERN CLASSIFICATION WITH HADAMARD TRANSFORMED NEURAL NETWORKS
Neural networks, trained with the backpropagation algorithm have: been applied to various classification problems. For linearly separable and nonseparahle problems, they have been shown to approximate the a posteriori probability of an input vector X belonging to a specific class C. In order to achieve high accuracy, large training data sets have to be used. For a small number of input dimensions, the accuracy of estimation was inferior to estimates using the Parzen density estimation. In this thesis, we propose two new techniques, lowering the mean square estimation error drastically and achieving better classification. In the past, t:he desired output patterns used for training have been of binary nature, using one for the class C the vector belongs to, and zero for the other classes. This work will show that by training against the columns of a Hadamard matrix, and then taking the inverse Hadamard transform of the network output, we can obtain more accurate estimates. The second change proposed in comparison with standard backpropagation networks will be the use of redundant output nodes. In standard backpropagat:ion the number of output nodes equals the number of different classes. In this thesis, it is shown that adding redundant output nodes enables us to decrease the mean square error at the output further, reaching better classification and lower mean square error rates than the Parzen density estimator. Comparisons between the statistical methods, the Parzen density estimation and histogramming, the conventional neural network and the Hadamard transformed neural network with redundant output nodes are given. Further, the effects of the proposed changes to the backpropagation algorithm on the convergence speed and the risk of getting stuck in a local minimum are: studied
Improved Foods Using Enzymes from Basidiomycetes
Within the kingdom of fungi, the division Basidiomycota represents more than 30,000 species, some with huge genomes indicating great metabolic potential. The fruiting bodies of many basidiomycetes are appreciated as food (“mushrooms”). Solid-state and submerged cultivation processes have been established for many species. Specifically, xylophilic fungi secrete numerous enzymes but also form smaller metabolites along unique pathways; both groups of compounds may be of interest to the food processing industry. To stimulate further research and not aim at comprehensiveness in the broad field, this review describes some recent progress in fermentation processes and the knowledge of fungal genetics. Processes with potential for food applications based on lipases, esterases, glycosidases, peptidases and oxidoreductases are presented. The formation and degradation of colourants, the degradation of harmful food components, the formation of food ingredients and particularly of volatile and non-volatile flavours serve as examples. In summary, edible basidiomycetes are foods—and catalysts—for food applications and rich donors of genes to construct heterologous cell factories for fermentation processes. Options arise to support the worldwide trend toward greener, more eco-friendly and sustainable processes
Compressible primitive equation: formal derivation and stability of weak solutions
We present a formal derivation of a simplified version of Compressible
Primitive Equations (CPEs) for atmosphere modeling. They are obtained from
-D compressible Navier-Stokes equations with an \emph{anisotropic viscous
stress tensor} where viscosity depends on the density. We then study the
stability of the weak solutions of this model by using an intermediate model,
called model problem, which is more simple and practical, to achieve the main
result
Cross-Linking of Wheat Bran Arabinoxylan by Fungal Laccases Yields Firm Gels
The native extractable arabinoxylans (AX) from wheat bran were cross-linked by the commercial laccase C (LccC) and self-produced laccases from Funalia trogii (LccFtr) and Pleurotus pulmonarius (LccPpu) (0.04 U/µg FA, each). Dynamic oscillation measurements of the 6% AX gels demonstrated a storage modulus of 9.4 kPa for LccC, 9.8 kPa for LccFtr, and 10.0 kPa for LccPpu. A loss factor ≤ 0.6 was recorded in the range from 20 to 80 Hz for all three laccases, and remained constant for four weeks of storage, when LccFtr and LccPpu were used. Arabinoxylan gel characteristics, including high water holding capacity, swelling ratio in saliva, and heat resistance indicated a covalently cross-linked network. Neither the mediator compounds caffeic acid and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), nor citrus pectin, enhanced the elastic properties of the gels. Using laccases as an oxidant provided gels with a solid and stable texture, comparable in firmness to traditional gelatin gels. Thus, AX gels can be presented in the vegan, halal, and kosher food markets. They may also find use in pharmaceutical and other industrial applications
Mutagenesis of the l-Amino Acid Ligase RizA Increased the Production of Bioactive Dipeptides
The l-amino acid ligase RizA from B. subtilis selectively synthesizes dipeptides containing an N-terminal arginine. Many arginyl dipeptides have salt-taste enhancing properties while Arg-Phe has been found to have an antihypertensive effect. A total of 21 RizA variants were created by site-directed mutagenesis of eight amino acids in the substrate binding pocket. The variants were recombinantly produced in E. coli and purified by affinity chromatography. Biocatalytic reactions were set up with arginine and four amino acids differing in size and polarity (aspartic acid, serine, alanine, and phenylalanine) and were analyzed by RP-HPLC with fluorescence detection. Variant T81F significantly improved the yield in comparison to wild type RizA for aspartic acid (7 to 17%), serine (33 to 47%) and alanine (12 to 17%). S84F increased product yield similarly for aspartic acid (7 to 17%) and serine (33 to 42%). D376E increased the yield with alanine (12 to 19%) and phenylalanine (11 to 26%). The largest change was observed for S156A, which showed a yield for Arg-Phe of 40% corresponding to a 270% increase in product concentration. This study expands the knowledge about positions governing the substrate specificity of RizA and may help to inform future protein engineering endeavors
Cross-Linking of Fibrex Gel by Fungal Laccase: Gel Rheological and Structural Characteristics
Sugar beet fibre (fibrex) is an abundant side-stream from the sugar refining industry. A self-produced laccase from Funalia trogii (LccFtr) (0.05 U/µg FA) successfully cross-linked fibrex to an edible gel. Dynamic oscillation measurements of the 10% fibrex gels showed a storage modulus of 5.52 kPa and loss factors ≤ 0.36 in the range from 20 to 80 Hz. Comparing storage stability of sweetened 10% fibrex gels with sweetened commercial 6% gelatin gels (10% and 30% d-sucrose) indicated a constant storage modulus and loss factors ≤ 0.7 during four weeks of storage in fibrex gels. Loss factors of sweetened gelatin gels were ≤0.2, and their storage modulus decreased from 9 to 7 kPa after adding d-sucrose and remained steady for four weeks of storage. Fibrex gel characteristics, including high water holding capacity, swelling ratio in saliva, and heat resistance are attributed to a covalently cross-linked network. Vanillin, as a mediator, and citrus pectin did not enhance covalent cross-links and elastic properties of the fibrex gels. Thus, laccase as an oxidative agent provided gels with a solid and stable texture. Fibrex gels may find uses in pharmaceutical and other industrial applications, which require a heat-resistant gel that forms easily at room temperature. They also represent an ethical alternative for manufacturing vegan, halal, and kosher food
Co-Immobilization of RizA Variants with Acetate Kinase for the Production of Bioactive Arginyl Dipeptides
The biocatalytic system comprised of RizA and acetate kinase (AckA) combines the specific synthesis of bioactive arginyl dipeptides with efficient ATP regeneration. Immobilization of this coupled enzyme system was performed and characterized in terms of activity, specificity and reusability of the immobilisates. Co-immobilization of RizA and AckA into a single immobilisate conferred no disadvantage in comparison to immobilization of only RizA, and a small addition of AckA (20:1) was sufficient for ATP regeneration. New variants of RizA were constructed by combining mutations to yield variants with increased biocatalytic activity and specificity. A selection of RizA variants were co-immobilized with AckA and used for the production of the salt-taste enhancers Arg-Ser and Arg-Ala and the antihypertensive Arg-Phe. The best variants yielded final dipeptide concentrations of 11.3 mM Arg-Ser (T81F_A158S) and 11.8 mM Arg-Phe (K83F_S156A), the latter of which represents a five-fold increase in comparison to the wild-type enzyme. T81F_A158S retained more than 50% activity for over 96 h and K83F_S156A for over 72 h. This study provides the first example of the successful co-immobilization of an l-amino acid ligase with an ATP-regenerating enzyme and paves the way towards a bioprocess for the production of bioactive dipeptides
Wannier-function approach to spin excitations in solids
We present a computational scheme to study spin excitations in magnetic
materials from first principles. The central quantity is the transverse spin
susceptibility, from which the complete excitation spectrum, including
single-particle spin-flip Stoner excitations and collective spin-wave modes,
can be obtained. The susceptibility is derived from many-body perturbation
theory and includes dynamic correlation through a summation over ladder
diagrams that describe the coupling of electrons and holes with opposite spins.
In contrast to earlier studies, we do not use a model potential with adjustable
parameters for the electron-hole interaction but employ the random-phase
approximation. To reduce the numerical cost for the calculation of the
four-point scattering matrix we perform a projection onto maximally localized
Wannier functions, which allows us to truncate the matrix efficiently by
exploiting the short spatial range of electronic correlation in the partially
filled d or f orbitals. Our implementation is based on the FLAPW method.
Starting from a ground-state calculation within the LSDA, we first analyze the
matrix elements of the screened Coulomb potential in the Wannier basis for the
3d transition-metal series. In particular, we discuss the differences between a
constrained nonmagnetic and a proper spin-polarized treatment for the
ferromagnets Fe, Co, and Ni. The spectrum of single-particle and collective
spin excitations in fcc Ni is then studied in detail. The calculated spin-wave
dispersion is in good overall agreement with experimental data and contains
both an acoustic and an optical branch for intermediate wave vectors along the
[100] direction. In addition, we find evidence for a similar double-peak
structure in the spectral function along the [111] direction.Comment: 16 pages, 11 figures, 5 table
A DyP-type peroxidase of pleurotus sapidus with alkene cleaving activity
Alkene cleavage is a possibility to generate aldehydes with olfactory properties for the fragrance and flavor industry. A dye-decolorizing peroxidase (DyP) of the basidiomycete Pleurotus sapidus (PsaPOX) cleaved the aryl alkene trans-anethole. The PsaPOX was semi-purified from the mycelium via FPLC, and the corresponding gene was identified. The amino acid sequence as well as the predicted tertiary structure showed typical characteristics of DyPs as well as a non-canonical Mn2+-oxidation site on its surface. The gene was expressed in Komagataella pfaffii GS115 yielding activities up to 142 U/L using 2,20-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) as substrate. PsaPOX exhibited optima at pH 3.5 and 40 ◦C and showed highest peroxidase activity in the presence of 100 µM H2O2 and 25 mM Mn2+. PsaPOX lacked the typical activity of DyPs towards anthraquinone dyes, but oxidized Mn2+ to Mn3+. In addition, bleaching of β-carotene and annatto was observed. Biotransformation experiments verified the alkene cleavage activity towards the aryl alkenes (E)-methyl isoeugenol, α-methylstyrene, and trans-anethole, which was increased almost twofold in the presence of Mn2+. The resultant aldehydes are olfactants used in the fragrance and flavor industry. PsaPOX is the first described DyP with alkene cleavage activity towards aryl alkenes and showed potential as biocatalyst for flavor production
- …