The results of the in situ exploration of the asteroid (4) Vesta by the Dawn spacecraft open new perspectives in the field of interpretation of remote-sensing polarimetric measurements of asteroids. ...(4) Vesta has long been known to be the only asteroid exhibiting a cyclic variation of the degree of linear polarization of the sunlight scattered by its surface, with a period which is synchronous with the object's rotation. This variation must be the consequence of some heterogeneity of the asteroid's surface, including regions characterized by different albedo, or composition, or regolith properties, or a combination of the above features. For a long time, this kind of conclusion has remained essentially qualitative. Now, after the extensive exploration of Vesta's surface by Dawn, it is possible to interpret the data set of polarimetric measurements of Vesta, including some unpublished data presented here for the first time, in terms of a correspondence between the degree of linear polarization and the variation of local properties of the surface visible to ground-based observers during Vesta's rotation, as seen at different epochs and under different illumination conditions. This makes it possible to refine our knowledge of the empirical relation between polarization properties and albedo, which is commonly used to derive the albedo from remote-sensing measurements of linear polarization of atmosphereless Solar system bodies.
The article presents the results of a study of chromosomal mutations in residents living in the Aral Sea disaster zone. The present study was designed to evaluate the impact of the combined effect of ...a chemical mutagen (nickel) and bacterial microflora on the level of chromosomal aberrations (CA) in peripheral blood lymphocytes. This study used classical methods of cell cultivation, methods for determining chromosomal aberrations, a cytomorphological method for assessing epithelial cells, and an atomic absorption method for determining trace elements in the blood. The article shows that with an increase of chemical agent in the blood, the number of cells with features of damage and cells with contamination by microflora increases. Both of these factors cause an increase in the frequency of chromosomal aberrations. The article demonstrates how being exposed to a chemical factor increases chromosomal mutations, and also damages membrane components, which leads to a decrease in the barrier and protective function of the cell, and as a result also affects the level of chromosomal aberrations.
•This was the first reported mortality due to listeria associated with alemtuzumab therapy in the setting of Multiple Sclerosis.•The rapid and fulminant presentation had symptoms which commonly occur ...following routine administration of alemtuzumab.•The Acute Phase post administration appears to confer particular vulnerability to this pathogen therefore high vigilance for this complication is mandatory.
We report the case of a patient who died from the rare complication of Listeriosis in the immediate phase following alemtuzumab administration one month after discontinuing dimethyl fumarate (DMF). There is considerable overlap with typical post-infusion symptoms therefore high surveillance and low threshold for empirical or possible prophylactic antibiotic therapy is advocated.
New transition metal complex of Pt(II) of the Schiff base ligand with (E)-2-((1-(thiophen-2-yl)ethylidene)amino)phenol HL have been synthesized using the ultrasonic irradiation and characterized by ...physicochemical and spectroscopic methods. The IR spectrum of Pt(II) complex showed that the coordination in metal ions via the imine N and S atoms. Magnetic and UV–Vis spectra showed that the geometrical structure of Pt(II) complex is square planar. The molar conductance data revealed that Pt(II) complex is non-electrolyte. The thermodynamic parameters for thermal decomposition of Pt(II) complex was calculated from analysis of the TG-DTG curves using Hörowitz–Metzger method. The fluorescence of the ligand HL and its Pt(II) complex in different solvents and pH conditions have also been studied in detail. The quenching of the fluorescence intensity of the ligand can be noted obviously, in the presence of Pt(II) ion. Geometry optimization of the compounds was calculated by semiempirical molecular orbital theory PM3 method using Hyperchem 7.52 program.
Display omitted
•Synthses of novel Pt(II) Schiff base complex by ultrasonic method.•Spectroscopic studies suggested that Pt(II) complex possess a square planar geometry.•The Schiff base ligand HL and its Pt(II) complex was exhibited fluorescent properties.•Molecular orbital calculations were performed using hyper Chem 7.52 program.
Nanopore technology for DNA sequencing is constantly being refined and improved. In strand sequencing a single strand of DNA is fed through a nanopore and subsequent fluctuations in the current are ...measured. A major hurdle is that the DNA is translocated through the pore at a rate that is too fast for the current measurement systems. An alternative approach is "exonuclease sequencing", in which an exonuclease is attached to the nanopore that is able to process the strand, cleaving off one base at a time. The bases then flow through the nanopore and the current is measured. This method has the advantage of potentially solving the translocation rate problem, as the speed is controlled by the exonuclease. Here we consider the practical details of exonuclease attachment to the protein alpha hemolysin. We employ molecular dynamics simulations to determine the ideal (a) distance from alpha-hemolysin, and (b) the orientation of the monophosphate nucleotides upon release from the exonuclease such that they will enter the protein. Our results indicate an almost linear decrease in the probability of entry into the protein with increasing distance of nucleotide release. The nucleotide orientation is less significant for entry into the protein.
We have compared the effect of increasing optode separation (range 0.7-5.5 cm) on the sensitivity of near infrared spectroscopy (NIRS) to discrete reductions in scalp and cerebral oxygenation in 10 ...healthy men (mean age 32, range 26-39 yr) using multichannel NIRS. During cerebral oligaemia (a mean reduction in middle cerebral artery flow velocity of 47%) induced by a mean reduction in end-tidal PCO2 of 2.4 kPa, the decrease in oxyhaemoglobin detected by NIRS became significantly greater with increasing optode separation (P < 0.0001). In response to scalp hyperaemia induced by inflation and release of a pneumatic scalp tourniquet, increases in oxyhaemoglobin became significantly smaller with increasing optode separation (P < 0.0002). These results are consistent with theoretical models of the behaviour of NIR light in the adult head and support the concept of using multi-detector NIRS to separate intra- and extracranial NIR signal changes. However, the emitter-detector separation used by currently available cerebral oximeters is not large enough to provide optimal spatial resolution.
Summary
While many intensive care clinicians in the UK continue to express significant concerns regarding controlled non‐heart beating organ donation, others are involved in established programmes ...that make an increasingly significant contribution to the total number of cadaveric donations each year. The successful introduction of a controlled non‐heart beating organ donation programme requires local resolution of any apparent ethicolegal obstacles to the process, with specific attention needing to be given to three areas: the potential conflict of interest between decision making over futility and any subsequent approach regarding organ donation; a belief that it may be unlawful to adjust in any way an end of life care pathway in order to allow donation to take place, and, finally, an uncertainty over how soon after cardiac death organ retrieval can begin. It is proposed that recent changes in legislation provide, through an emphasis on patient autonomy and best interests, a solid ethicolegal foundation for donation after cardiac death.
Next generation DNA sequencing methods that utilize protein nanopores have the potential to revolutionize this area of biotechnology. While the technique is underpinned by simple physics, the ...wild-type protein pores do not have all of the desired properties for efficient and accurate DNA sequencing. Much of the research efforts have focused on protein nanopores, such as α-hemolysin from Staphylococcus aureus. However, the speed of DNA translocation has historically been an issue, hampered in part by incomplete knowledge of the energetics of translocation. Here we have utilized atomistic molecular dynamics simulations of nucleotide fragments in order to calculate the potential of mean force (PMF) through α-hemolysin. Our results reveal specific regions within the pore that play a key role in the interaction with DNA. In particular, charged residues such as D127 and K131 provide stabilizing interactions with the anionic DNA and therefore are likely to reduce the speed of translocation. These regions provide rational targets for pore optimization. Furthermore, we show that the energetic contributions to the protein–DNA interactions are a complex combination of electrostatics and short-range interactions, often mediated by water molecules.
A single solid-state magnetic sensor can measure a current flowing in a conductor in a noncontact way. In order to improve the accuracy of the measuring system and to reduce the crosstalk effects of ...other magnetic fields, circular arrays of magnetic sensors can be fabricated, still preserving low costs. In those kind of arrays, the sensing elements are assembled on a circle around the conductor. The sum of the sensor output signals is an approximation of Ampere's circulation. A quite satisfactory crosstalk effects reduction can be thus achieved. More sophisticated algorithms that combine sensor output signals are necessary in order to further reduce crosstalk effects. This paper presents an algorithm that is able to calculate the intensity of a dc current flowing in a rectangular bus-bar, in the presence of crosstalk fields.
This study describes: 1. The therapeutic effects on anorexia nervosa (AN) and bulimia nervosa (BN) patients of a psycho-nutritional intensive day-hospital program; 2. The possible correlation between ...the changes observed in the psychometric tests and the variations of a number of biological parameters. Forty-six female patients (24 AN and 22 BN) were assessed through a semi-structured clinical interview based on DSM-IV criteria for Eating Disorders (ED) and a number of psychometric tests (SCL-90R, BDI, EDI-2, EAT-40, BITE, BAT) at the beginning and at the end of treatment, and after a 6-month follow-up. At these three times, we also assessed the plasma level of leptin, cortisol, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and 17beta-estradiol together with body mass index (BMI) and menstrual cycle. From beginning to discharge, the scores on all psychometric tests improved in the whole sample, except for the Perfectionism subscale of EDI-2 in both groups (AN and BN), the Anger-Hostility, Phobic Anxiety and Paranoid Ideation subscales of SCL-90 and the Interpersonal Distrust subscale of EDI-2 in the BN group. At follow-up, there was a worsening of the BITE scores and of a number of EDI-2 subscales, especially in the AN subgroup - with these changes correlating with the trend of BMI. In AN patients, plasma leptin levels changed from the beginning to the end of treatment and at follow-up according to BMI changes. The mean plasma leptin level in the BN subgroup was higher than in the AN one. We found a statistically significant correlation with the scores of BDI, SCL-90R Depression and Ineffectiveness subscales, EAT-40, BITE-Symptom subscale and the trend of menses dividing these patients into two subgroups (according to the plasma leptin concentration, higher or lower than the top leptin level in the anorexics). These data seem to confirm that leptin secretion doesn't correlate univocally to BMI.
PDF
