Mars Orbiter Laser Altimeter: Experiment summary after the first year of global mapping of Mars

The Mars Orbiter Laser Altimeter (MOLA), an instrument on the Mars Global Surveyor spacecraft, has measured the topography, surface roughness, and 1.064-μm reflectivity of Mars and the heights of volatile and dust clouds. This paper discusses the function of the MOLA instrument and the acquisition, processing, and correction of observations to produce global data sets. The altimeter measurements have been converted to both gridded and spherical harmonic models for the topography and shape of Mars that have vertical and radial accuracies of ~1 m with respect to the planet's center of mass. The current global topographic grid has a resolution of 1/64° in latitude × 1/32° in longitude (1 × 2 km^2 at the equator). Reconstruction of the locations of incident laser pulses on the Martian surface appears to be at the 100-m spatial accuracy level and results in 2 orders of magnitude improvement in the global geodetic grid of Mars. Global maps of optical pulse width indicative of 100-m-scale surface roughness and 1.064-μm reflectivity with an accuracy of 5% have also been obtained

Exploring the Impact of Third-Party Web Tracking on the Healthcare Providers’ Business Value

Organizations worldwide have been widely utilizing Internet and networking technologies to reach out the potential customers and positively impact its business outcomes. By signaling its quality- and behavior-related characteristics to online users, hospitals, are able to reduce information asymmetry and positively impact the hospital selection process. To facilitate the signaling process, many commonly rely on the third-party web tracking (TPWT) technologies. This study seeks to answer if the benefits of online engagement though TPWT are substantial enough to outweigh the potential risks associated with it. The preliminary results indicate: (1) web tracking significantly impacts the business value; and (2) its direction and magnitude vary depending on the tracker type (i.e., the impact of ad networks is negative (-18%), and that of customer engagement and website analytics is positive (25% and 55%, respectively)

SU(2) reductions in N=4 multidimensional supersymmetric mechanics

We perform an su(2) Hamiltonian reduction in the bosonic sector of the su(2)-invariant action for two free (4, 4, 0) supermultiplets. As a result, we get the five dimensional N=4 supersymmetric mechanics describing the motion of an isospin carrying particle interacting with a Yang monopole. We provide the Lagrangian and Hamiltonian descriptions of this system. Some possible generalizations of the action to the cases of systems with a more general bosonic action, a four-dimensional system which still includes eight fermionic components, and a variant of five-dimensional N=4 mechanics constructed with the help of the ordinary and twisted N=4 hypermultiplets were also considered.Comment: 11 pages, LaTeX file, no figures; 3 references added, minor correction

Peritoneal metastases in colorectal cancer

Peritoneal carcinomatosis (PC) is a common evolution of cancer of the gastrointestinal tract, and has been traditionally regarded as a terminal disease with short median survival. During the last 20 years, due to its favourable oncologic results, a new loco-regional therapeutic approach, combining cytoreductive surgery with intra-operative intraperitoneal chemotherapy has achieved an important development. After liver metastatic disease, peritoneal carcinomatosis is the second most frequent cause of death in colorectal cancer patient is defined as a stage IV tumour which prognosis is the worst. The extent of peritoneal carcinomatosis is, however, difficult for assessment preoperatively, and precise evaluation is most often performed during surgical exploration. Cytoreductive surgery associated with chemotherapy for the treatment of peritoneal carcinomatosis should be performed in young patients with limited and resectable carcinomatosis, in specialized institutions involved in the management of peritoneal surface malignancies

Heat increments and oxidation enthalpies of (Y,Pr,Gd)BaCo2O6-δ double perovskites

Complex oxides (Y,Gd,Pr)BaCo2O6-δ attracts researchers’ attention due to it are promising materials for cathodes for solid state fuel cells. However, fundamental thermodynamic properties of these double perovskites such as heat increments, heat capacity and enthalpy of oxidation are not investigated so far. Powder samples of (Y,Gd,Pr)BaCo2O6-δ were prepared using glycerol–nitrate technique. Phase composition of investigated double perovskites was controlled by X-ray powder diffraction. Then samples with composition GdBaCo2O5.51, PrBaCo2O5.77, YBaCo2O5.33 were prepared by slowly cooling with speed rate 100 K/h, whereas sample YBaCo2O5.0 was prepared by annealing at 1373 K and quenching. Enthalpy increments of all as-prepared samples were measured by high temperature drop-calorimetry method on the SETARAM MHTC 96 calorimeter. Since YBaCo2O6-δ is stable only above 1123 K in air, calorimetry measurements were carried out in region 1123≤T, K≤1323. Oxidation enthalpies of (Gd,Pr)BaCo2O6-δ were measured by means of DSC sensors of MHTC 96 calorimeter at 1173K. Oxidation enthalpy of YBaCo2O6-δ was calculated from heat increments measurements. Obtained data allow us to calculate a heat capacity dependency from temperature for these compounds. Acknowledgement: This study was supported by the Russian Foundation for Basic Research (Grant No. 18-33-20243)