Determination of Ceres mass based on the most gravitationally efficient close encounters

Here is presented recalculated value of the mass of Ceres, based on explicit tracking of its gravitational influence on orbits evolution of 21 selected asteroids during their mutual close encounters (CE). It was applied a new modified method (MM) for mass determination, based on the connecting of pre-encounter observations to the orbit determined from post-encounter ones. The calculated weighted mean value of Ceres mass, based on modified method, is $(4.54\pm0.07)\,10^{-10}M_{\odot}$ while standard procedure (SM) provided result of $(4.70\pm0.04)\,10^{-10}M_{\odot}$. We found that correlation between individual estimated masses based on modified and standard method is 0.78, which confirms reliability of using modified method.Comment: MNRAS:Accepted 2011 September 28. Received 2011 September 28; in original form 2011 January 2

Meat consumption: theory, practice and future prospects

This research reviewed human meat consumption and highlighted associated history, challenges and benefits. Selected literature for the manuscript was from relevant titles and reliable international sources. From early times of the mankind meat consumption and animal husbandry were inseparable parts of living, and with similar consequences as dramatic influence on environment. Human need for meat consumption fueled development of large world markets with incredible trade, processing and consumption. This overconsumption has caused health problems associated with high intake of cholesterol and sodium chloride. Another problem with meat consumption is the use of additives in processed products. In modern time these problems are tackled by the use of additives from plants that have health benefits. Thermal processing is yet another problem with meat consumption that food industry and science addresses by non-thermal replacements (e. g. high-pressure processing and electrotechnologies). Recently, interesting alternatives for meat processing included 3D Printing that is able to engineer admirable meat products from by-products. However, this technology might need to employ enzymes such as transglutaminase, associated with potential health problems and misleading the customers. Unfortunately, fraudulent activities are common for meat products and it would be prudent to organize enforcement centers with at least police and analysts skilled in chemometrics and various laboratory techniques for food defense. It seems as humankind expands it will seek more proteins from plant, insects, unicellular biomass, and synthetic meat than from the animal origin, however all of the alternatives must be carefully evaluated against consumer acceptance, public health and environmental concerns

Usporedba internetskih i papir-olovka ispitivanja zadovoljstva poslom

Parallel to the rising availability and application of Web-based organizational research, the issue of its validity becomes increasingly important. The research was designed to reveal any existing differences in job satisfaction survey data gathered using Intranet and paper-and-pencil administration modes. A sample of employees in one large organization in Serbia (N = 1923), answered either Intranet (N = 425) or paper-based job satisfaction survey (N = 1498). A 50-item version of a Job Satisfaction Scale was highly reliable for both data collection techniques. There was a significant method effect on all the checked indicators: demographic characteristics of Intranet and paper sub-samples based (gender, age, length of service and educational level); proportion of missing answers (on items about job satisfaction and demographic data), satisfaction with specific items and dimensions of job satisfaction, as well as overall job satisfaction. Interaction effects of administration mode by gender, age, length of service and education were not significant. Results stress that before accepting Webbased organizational surveys as a new gold standard we need empirical evidence that Web-based data can be combined and/or compared with paper-based data.Usporedo sa sve većom dostupnosti i primjenom internetskih organizacijskih istraživanja, pitanje njihove valjanosti postaje sve važnije. Istraživanje je usmjereno na pitanje postoje li razlike u podacima o zadovoljstvu poslom prikupljenih pomoćuintraneta i papir-olovka upitnika. Uzorak su činili zaposlenici velike tvrtke u Srbiji (N = 1923), koji su odgovorili na upitnike pomoću intraneta (N = 425) ili papir-olovka upitnika (N = 1498). Ljestvica zadovoljstva poslom od 50 čestica pokazala se visokopouzdanom za obje metode prikupljanja podataka. Utvrđen je značajan utjecaj metode na sve označene pokazatelje: sastav intranet i papir-olovka poduzoraka na temelju spola, dobi, staža i obrazovanja; udio neodgovorenih pitanja (na česticama o zadovoljstvu poslom i demografskim podacima), zadovoljstvo s određenim facetama (česticama) i dimenzijama zadovoljstva poslom te ukupno zadovoljstvo poslom. Interakcijski pokazatelji za spol, dob, staž i razinu obrazovanja u obje skupine nisu bili značajni. Rezultati upućuju na potrebu za jasnim rezultatima o mogućnostima generalizacije takvih upitnika prije njihova postavljanja kao standarda ispitivanja

The Action of Hydrazines upon \u27Thiazolidine-4-carboxylic Acids I. Preparation of D-Penicillamine from D-Benzylpenilloic Acid

In the reaction of phenylhydrazine with n-benzylpenilloic acids (Ia or Ila) n-penicillamine was obtained in high yield and purity. The lack of reactivity of N-acyl derivatives (Ib or Ub) with phenylhydrazine indicated that the above reaction proceeded through the open chain imine tautomer of Ia or Ila (IV). The epim~risation of n-benzylpenilloic acid (Ia and Ha) in aprotic solvents was studied by using PMR spectroscopy

Geometry of Molecules. Part 4. Iterative Maximum Overlap Calculations of lnteratomic Distances, Bond Angles and Strain Energies in Some Rotanes and Related Spiro-Compounds

The iterative maximum overlap approximation (IMOA) is applied to a series of [n]-rotanes and some related spiro-compounds of unusual topology. The properties of these molecules were discussed in terms of the local hybrid orbitals and extent of their overlapping. Necessity of a clear distinction between bond length and interatomic distance in strained systems is pointed out. Considerableshortening of the C-C interatomic distance of the central carbocycles in [n]-rotanes was established. It was rationalized by the bent bond concept. The delocalization of the pseudo-pi electrons around the central ring in [n]-rotanes is briefly discussed. Angular strain energy and its distribution over the molecular fragments was quantitatively considered in the studied compounds. The strain and heat of formation of spiro (3.3) heptane are favourably compared with available ab initio results

Ring Expansion of Thiazolidine and Nucleophilic Substitution in N-Acyl Derivatives of 6-Thia-3,8-diazabicyclo[3.2.1. ]octan-2-one

Reaction of N3,N8-diacyl 6-thia-3,8-diazabicyclo/3.2. l./octan-2- -one (I) with PC15 or S02Cl2 gave 6-chloro substituted N2,N5-diacyl 7-thia-2,5-diazabicyclo/2.2.2./octan-3-one (II). Treatment of II with water yielded the 6-hydroxy derivative (III) while reaction with methanol gave the 6-methoxy derivative (IV). Under the same reaction conditions the mono N8-acyl derivative (V) gave a mixture of 6-substituted 7-thia-2,5-diazabicyclo/2.2.2./octan-3-one and 4- -su bsti tuted 6-thia-3,8-diazabicyclo/3.2. l ./octan-2-one derivatives (XIV and XV; VI and VII; VIII and IX). It was proposed that ring expansion of thiazolidine and nucleophilic substitution occured vi a the thiiranium ion XIII as a common intermediate

Hermite-Gaussian Expansion of Hydrogenic Orbitals

Hydrogen ls, 2s, 2p, 3s, 3p, 3d, 4s, 4p and 4d (HO) orbitals are expanded in series of Hermite-Gaussian (HG) functions. Adjustable parameters are determined by the integral least-square fit procedure. HG approximation of the fourth degree (HG4) proved particularly good and useful in representing hydrogen AOs. It yields hydrogen (and hydrogen-Iike) orbitals which are more accurately described than the corresponding GTO expansion. Hydrogen type orbitals (HTO) expressed in HG4 bases could be useful in molecular calculations involving heavier atoms because some STO orbi ta ls do not perform well for higher principal quantum numbers. Use of STOs for inner-shells and HOs for outer valence shell electrons in heavy atoms might be advantageous. Both types of atomic orbitals could be well represented by HG functions. HG representation of polarization functions, which play an important role in describing charge redistribution upon formation of chemical bonds and are crucial in treating anions, might be useful too. The HG functions may also serve a purpose in solving the Schrodinger equation in momentum representation and in calculations of the X-ray scattering factors

The Habitability of the Galactic Bulge

We present a new investigation of the habitability of the Milky Way bulge, that expands previous studies on the Galactic Habitable Zone. We discuss existing knowledge on the abundance of planets in the bulge, metallicity and the possible frequency of rocky planets, orbital stability and encounters, and the possibility of planets around the central supermassive black hole. We focus on two aspects that can present substantial differences with respect to the environment in the disk: (i) the ionizing radiation environment, due to the presence of the central black hole and to the highest rate of supernovae explosions and (ii) the efficiency of putative lithopanspermia mechanism for the diffusion of life between stellar systems. We use analytical models of the star density in the bulge to provide estimates of the rate of catastrophic events and of the diffusion timescales for life over interstellar distances.Comment: Published in Lif