491 research outputs found
LHC main dipoles proposed baseline current ramping
Several studies performed from 1994 to 1996 including some in the framework of the Dynamic Effects Working Group, have shown that the magnitude of the magnetic field imperfections generated in the LHC main dipoles depends partly on the shape of the magnetic field ramp. A current ramp optimisation has been carried out with several combinations of mathematical functions. The result of this study is t he proposed baseline current ramp. The graphic representation of this ramp is included in this report. Theoretical dynamic errors expected with this ramp are compared with those produced with a straig ht ramp at constant current rate, thus demonstrating the improvement obtained. A set of formulae and parameters required for the actual calculation of the baseline ramp is given in the Appendix
Prion expression is activated by Adenovirus 5 infection and affects the adenoviral cycle in human cells
The prion protein is a cell surface glycoprotein whose physiological role remains elusive, while its implication
in transmissible spongiform encephalopathies (TSEs) has been demonstrated. Multiple interactions between
the prion protein and viruses have been described: viruses can act as co-factors in TSEs and life cycles of
different viruses have been found to be controlled by prion modulation.
We present data showing that human Adenovirus 5 induces prion expression. Inactivated Adenovirus did
not alter prion transcription, while variants encoding for early products did, suggesting that the prion is
stimulated by an early adenoviral function. Down-regulation of the prion through RNA interference showed
that the prion controls adenovirus replication and expression.
These data suggest that the prion protein could play a role in the defense strategy mounted by the host
during viral infection, in a cell autonomous manner. These results have implications for the study of the prion
protein and of associated TSEs
Optimisation of the Current Ramp for the LHC
The field quality of the main magnets in the LHC will be, in part, dependent upon the shape of the magnetic field as a function of time. A theoretical optimisation of this function has been carried-out with the aim of minimising the dynamic errors [3]. This work resulted in the definition of a current ramp function composed of mathematically defined, smoothly joining segments. A prototype digital controller based on a DSP has been developed and built [4]. In this equipment the current ramp is computed from the segment equations in real time. The user need only supply the characteristic parameters for the segments in order to define the ramp. In this paper, the effect of the ramp function on the error terms is discussed and the corresponding segment equations are given. The prototype implementation is described and actual results are shown
4,5-Dimethyl-1,2-diphenyl-1H-imidazole monohydrate
In the title compound, C17H16N2·H2O, the imidazole ring is essentially planar [maximum deviation = 0.0037 (7) Å]. The imidazole ring makes dihedral angles of 80.74 (7) and 41.62 (7)° with the phenyl rings attached to the N and C atoms, respectively. The dihedral angle between the two phenyl rings is 75.83 (8)°. Intermolecular O—H⋯N and O—H⋯O hydrogen bonds are found in the crystal structure
rac-4-(2-Methoxyphenyl)-2,6-dimethylcyclohex-3-enecarboxylic acid
The title compound, C16H20O3, was synthesized to study the hydrogen-bonding interactions of the two enantiomers in the solid state. Intermolecular O—H⋯O hydrogen bonds produce centrosymmetric R
2
2(8) rings which dimerize the two chiral enantiomers together through their carboxyl groups
Reversal of hemochromatosis by apotransferrin in non-transfused and transfused Hbbth3/+ (heterozygous b1/b2 globin gene deletion) mice
Arañas y carábidos como potenciales bioindicadores en ambientes con distinto grado de intervención antrópica en el este uruguayo: un estudio preliminar = Spiders and carabids as potential bioindicators in Eastern Uruguayan environments with different degree of anthropic intervention: a preliminary study
Algunos grupos de artrópodos son considerados buenos indicadores de calidad ambiental. Para ello deben cumplir con algunas condiciones, como poseer características biológicas y morfológicas que faciliten su hallazgo e identificación. Las trampas de caída (pitfall) son ampliamente utilizadas para recolectar artrópodos predadores potencialmente bioindicadores de las características del ambiente que ocupan. Se realizaron recolecciones quincenales, durante nueve meses, en tres sistemas productivos con diferente grado de intervención antrópica en la cuenca de la Laguna Negra, Rocha: área con baja intensidad de pastoreo de vacunos; área con bajo pastoreo de ganado vacuno y ovino, y área con altas cargas de ganado vacuno y agricultura inverno-estival. En cada área se instalaron dos series de 10 trampas pitfall separadas a una distancia mínima de 100 m y a una distancia de 10 m entre trampas. Dos morfoespecies de arañas, Mesabolivar sp (Pholcidae) y Steatoda sp (Theridiidae), fueron determinadas como indicadoras de los ambientes con menor y mayor intensidad de disturbio, respectivamente. Otras cuatro morfoespecies, pertenecientes a las familias Nemesiidae, Oxyopidae, Lycosidae y Palpimanidae, fueron caracterizadas como detectoras de los diferentes ambientes. Cuatro morfoespecies de coleópteros de la familia Carabidae (Calosoma retusum, Galerita collaris, Brachinus sp y Pelecium sp) resultaron indicadoras del ambiente de mayor intensidad productiva, con agricultura
7-(4-Methoxyphenyl)-5-methyl-9-phenyl-7H-pyrrolo[2′,3′:4,5]pyrimido[1,6-d]tetrazole
The title compound, C20H16N6O, is composed of a tetrazolo ring and a 4-methoxyphenyl and a benzene-substituted pyrrole ring at the 7 and 9 positions fused to a pyrimidine ring in a nearly planar fashion [maximum deviation of 0.018 (1) Å for the fused ring system]. A methyl group at the 5 position is also in the plane of the hetero cyclic system. The dihedral angle between the mean planes of the benzene and 4-methoxyphenyl rings is 40.4 (2)°. The dihedral angles between the mean planes of the pyrimidine and the benzene and 4-methoxyphenyl rings are 15.6 (5)° and 52.6 (7)°, respectively. A weak intramolecular C—H⋯N hydrogen bond interaction, which forms an S(7) graph-set motif, helps to establish the relative conformations of the tetrazolo and benzene rings. In the crystal, weak intermolecular C—H⋯O, C—H⋯π and π–π stacking interactions [centroid–centroid distances = 3.5270 (16), 3.5113 (16), 3.7275 (17) and 3.7866 (17) Å] link the molecules into a two-dimensional array obliquely parallel to (101) and propagating along the b axis
L’adattamento psicologico alla diagnosi di diabete di tipo 2.
SUMMARY Psychological adjustment to type 2 diabetes Objective. Based upon the literature of the past ten years, this study analyzes the initial phase of psychological adjustment after a diagnosis of type 2 diabetes, with the goal of providing useful guidelines to diabetologists in supporting their patients from the very first moment of clinical work. The study identifies five functional areas that characterize this adjustment: anxiety, depression, locus of control, self-esteem and self-efficacy. Method. Using a battery of psychometric tests, we assessed the psychological condition in a sample of 42 subjects with type 2 diabetes, comparing with a control sample of 420 subjects, without diabetes. Results. The initial psychological adjustment after six months from diagnosis, seems characterized by decreased tone of mood and self-efficacy, without anxious symptoms. The subjects seem to develop a fatalistic attitude or a strong external entrustment, showing inclination to underestimate the disease’s reality and to seek external dependence that could affect the path towards an adequate and effective self-management. Conclusions. The authors discuss the findings emerged and possible directions for a smoother working relationship between diabetologists and their patients
Changes in gene expression in human skeletal stem cells transduced with constitutively active Gs\u3b1 correlates with hallmark histopathological changes seen in fibrous dysplastic bone
Fibrous dysplasia (FD) of bone is a complex disease of the skeleton caused by dominant activating mutations of the GNAS locus encoding for the \u3b1 subunit of the G protein-coupled receptor complex (Gs\u3b1). The mutation involves a substitution of arginine at position 201 by histidine or cysteine (Gs\u3b1R201H or R201C), which leads to overproduction of cAMP. Several signaling pathways are implicated downstream of excess cAMP in the manifestation of disease. However, the pathogenesis of FD remains largely unknown. The overall FD phenotype can be attributed to alterations of skeletal stem/progenitor cells which normally develop into osteogenic or adipogenic cells (in cis), and are also known to provide support to angiogenesis, hematopoiesis, and osteoclastogenesis (in trans). In order to dissect the molecular pathways rooted in skeletal stem/progenitor cells by FD mutations, we engineered human skeletal stem/progenitor cells with the Gs\u3b1R201C mutation and performed transcriptomic analysis. Our data suggest that this FD mutation profoundly alters the properties of skeletal stem/progenitor cells by pushing them towards formation of disorganized bone with a concomitant alteration of adipogenic differentiation. In addition, the mutation creates an altered in trans environment that induces neovascularization, cytokine/chemokine changes and osteoclastogenesis. In silico comparison of our data with the signature of FD craniofacial samples highlighted common traits, such as the upregulation of ADAM (A Disintegrin and Metalloprotease) proteins and other matrix-related factors, and of PDE7B (Phosphodiesterase 7B), which can be considered as a buffering process, activated to compensate for excess cAMP. We also observed high levels of CEBPs (CCAAT-Enhancer Binding Proteins) in both data sets, factors related to browning of white fat. This is the first analysis of the reaction of human skeletal stem/progenitor cells to the introduction of the FD mutation and we believe it provides a useful background for further studies on the molecular basis of the disease and for the identification of novel potential therapeutic targets
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