Diversity of Sinorhizobium meliloti from the Central Asian Alfalfa Gene Center

Sinorhizobium meliloti was isolated from nodules and soil from western Tajikistan, a center of diversity of the host plants (Medicago, Melilotus, and Trigonella species). There was evidence of recombination, but significant disequilibrium, between and within the chromosome and megaplasmids. The most frequent alleles matched those in the published genome sequence

Symbiotic and genetic diversity of Rhizobium galegae isolates collected from the Galega orientalis gene center in the Caucasus

This paper explores the relationship between the genetic diversity of rhizobia and the morphological diversity of their plant hosts. Rhizobium galegae strains were isolated from nodules of wild Galega orientalis and Galega officinalis in the Caucasus, the center of origin for G. orientalis. All 101 isolates were characterized by genomic amplified fragment length polymorphism fingerprinting and by PCR-restriction fragment length polymorphism (RFLP) of the rRNA intergenic spacer and of five parts of the symbiotic region adjacent to nod box sequences. By all criteria, the R. galegae bv. officinalis and R. galegae bv. orientalis strains form distinct clusters. The nod box regions are highly conserved among strains belonging to each of the two biovars but differ structurally to various degrees between the biovars. The findings suggest varying evolutionary pressures in different parts of the symbiotic genome of closely related R. galegae biovars. Sixteen R. galegae bv. orientalis strains harbored copies of the same insertion sequence element; all were isolated from a particular site and belonged to a limited range of chromosomal genotypes. In all analyses, the Caucasian R. galegae bv. orientalis strains were more diverse than R. galegae bv. officinalis strains, in accordance with the gene center theory

Incentives and Job Satisfaction: Its Implications for Competitive Positioning and Organizational Survival in Nigerian Manufacturing Industries

This paper assessed the attitude of workers towards incentive and their satisfaction to work. A sample of 127 valid respondents selected from the managerial and non-managerial staff and data collected were analyzed using Statistical Package for Social Science (SPSS) through descriptive statistics and regression. The findings revealed that financial rewards encourage workers externally; while nonfinancial rewards can satisfy employees internally by making them feel like a valued part of an organization. Also, it was indicated that some employees seem to be satisfied and content with their job not because they derive pleasure from the work itself but because there are no other alternatives. The manufacturing industry needs to embark on the restructuring of jobs and responsibilities in ways that would facilitate competitive advantage without sacrificing the basic objective of the organization

Assessment of patients knowledge and attitude towards diabetes and its relationship with glycemic control: a cross-sectional study in a Nigerian tertiary hospital

Background: It is postulated that increased knowledge of patients about diabetes as well as a positive attitude will lead to improved glycaemic control and better outcome. The aim of this study was to determine the knowledge and attitude of diabetic patients in a tertiary hospital in Enugu and the relationship with their glycaemic control.Methods: A cross-sectional study was done using a structured questionnaire to obtain socio-demographic data and assess knowledge and attitude to diabetes on consecutive patients attending the outpatient clinic in a tertiary hospital. Responses were scored with equal weighting. The fasting blood glucose of the patients was measured and recorded.Result: There were 51(60.7%) females and 33 (39.3%) males, with majority (63.1%) in the age range 41 -64 years and 32(38.1%) had only primary education. The mean knowledge score was 6.19 ± 2.08 and 33(39.3%) demonstrated good knowledge. Knowledge did not differ between males and females (p=0.34), but was highest in those with tertiary education (p = 0.02). Positive attitude to the condition was recorded in 63(75%) subjects. There was poor correlation between knowledge and attitude (r = -0.161, p= 0.14). Those with good knowledge scores were 2 times more likely to have good glycaemic control compared with those with poor knowledge; OR = 2.015, p = 0.02. There was no significant difference between the glycemic control of those with good attitude and those with poor attitude (p= 0.08).Conclusion: Although overall knowledge was poor, patients had a good attitude to their illness. Knowledge, but not attitude was significantly positively associated with glycemic control.Keywords: Diabetes mellitus, Knowledge, Attitude, Glycaemic contro

The common ‘thermolabile' variant of methylene tetrahydrofolate reductase is a major determinant of mild hyperhomocysteinaemia

Mild hyperhomocysteinaemia is a major risk factor for vascular disease and neural tube defects (NTDs), conferring an approximately three-fold relative risk for each condition. It has several possible causes: heterozygosity for rare loss of function mutations in the genes for 5,10-methylene tetrahydrofolate reductase (MTHFR) or cystathionine-β-synthase (CBS); dietary insufficiency of vitamin co-factors B6, B12 or folates; or homozygosity for a common ‘thermolabile' mutation in the MTHFR gene which has also been associated with vascular disease and NTDs. We quantified the contribution of the thermolabile mutation to the hyperhomocysteinaemic phenotype in a working male population (625 individuals). Serum folate and vitamin B12 concentrations were also measured and their relationship with homocysteine status and MTHFR genotype assessed. The homozygous thermolabile genotype occurred in 48.4, 35.5, and 23.4% of the top 5,10, and 20% of individuals (respectively) ranked by plasma homocysteine levels, compared with a frequency of 11.5% in the study population as a whole, establishing that the mutation is a major determinant of homocysteine levels at the upper end of the range. Serum folate concentrations also varied with genotype, being lowest in thermolabile homozygotes. The MTHFR thermolabile genotype should be considered when population studies are designed to determine the effective homocysteine-lowering dose of dietary folate supplements, and when prophylactic doses of folate are recommended for individual

Novel order parameter to describe the critical behavior of Ising spin glass models

A novel order parameter $\Phi$ for spin glasses is defined based on topological criteria and with a clear physical interpretation. $\Phi$ is first investigated for well known magnetic systems and then applied to the Edwards-Anderson $\pm J$ model on a square lattice, comparing its properties with the usual $q$ order parameter. Finite size scaling procedures are performed. Results and analyses based on $\Phi$ confirm a zero temperature phase transition and allow to identify the low temperature phase. The advantages of $\Phi$ are brought out and its physical meaning is established.Comment: 13 pages, 4 figures, to appear in Physica

Limitations of the heavy-baryon expansion as revealed by a pion-mass dispersion relation

The chiral expansion of nucleon properties such as mass, magnetic moment, and magnetic polarizability are investigated in the framework of chiral perturbation theory, with and without the heavy-baryon expansion. The analysis makes use of a pion-mass dispersion relation, which is shown to hold in both frameworks. The dispersion relation allows an ultraviolet cutoff to be implemented without compromising the symmetries. After renormalization, the leading-order heavy-baryon loops demonstrate a stronger dependence on the cutoff scale, which results in weakened convergence of the expansion. This conclusion is tested against the recent results of lattice quantum chromodynamics simulations for nucleon mass and isovector magnetic moment. In the case of the polarizability, the situation is even more dramatic as the heavy-baryon expansion is unable to reproduce large soft contributions to this quantity. Clearly, the heavy-baryon expansion is not suitable for every quantity.Comment: Accepted for publication in EPJ C. Made changes based on referee comments: clarifying sentences to conclusion 1. of Section IV, beginning of Section V, and new footnote in Section VI, page 8. Added more detailed explanation in paragraph 4 of Section III. Added citations of Phys.Rev. D60, 034014, and Phys.Lett. B716, 33

Electron self-trapping in intermediate-valent SmB6

SmB6 exhibits intermediate valence in the ground state and unusual behaviour at low temperatures. The resistivity and the Hall effect cannot be explained either by conventional sf-hybridization or by hopping transport in an impurity band. At least three different energy scales determine three temperature regimes of electron transport in this system. We consider the ground state properties, the soft valence fluctuations and the spectrum of band carriers in n-doped SmB6. The behaviour of excess conduction electrons in the presence of soft valence fluctuations and the origin of the three energy scales in the spectrum of elementary excitations is discussed. The carriers which determine the low-temperature transport in this system are self-trapped electron-polaron complexes rather than simply electrons in an impurity band. The mechanism of electron trapping is the interaction with soft valence fluctuations.Comment: 12 pages, 3 figure

A quantitative theory-versus-experiment comparison for the intense laser dissociation of H2+

A detailed theory-versus-experiment comparison is worked out for H$_2^+$ intense laser dissociation, based on angularly resolved photodissociation spectra recently recorded in H.Figger's group. As opposite to other experimental setups, it is an electric discharge (and not an optical excitation) that prepares the molecular ion, with the advantage for the theoretical approach, to neglect without lost of accuracy, the otherwise important ionization-dissociation competition. Abel transformation relates the dissociation probability starting from a single ro-vibrational state, to the probability of observing a hydrogen atom at a given pixel of the detector plate. Some statistics on initial ro-vibrational distributions, together with a spatial averaging over laser focus area, lead to photofragments kinetic spectra, with well separated peaks attributed to single vibrational levels. An excellent theory-versus-experiment agreement is reached not only for the kinetic spectra, but also for the angular distributions of fragments originating from two different vibrational levels resulting into more or less alignment. Some characteristic features can be interpreted in terms of basic mechanisms such as bond softening or vibrational trapping.Comment: submitted to PRA on 21.05.200

Automated Detection of EUV Polar Coronal Holes During Solar Cycle 23

A new method for automated detection of polar coronal holes is presented. This method, called perimeter tracing, uses a series of 171, 195, and 304 \AA\ full disk images from the Extreme ultraviolet Imaging Telescope (EIT) on SOHO over solar cycle 23 to measure the perimeter of polar coronal holes as they appear on the limbs. Perimeter tracing minimizes line-of-sight obscurations caused by the emitting plasma of the various wavelengths by taking measurements at the solar limb. Perimeter tracing also allows for the polar rotation period to emerge organically from the data as 33 days. We have called this the Harvey rotation rate and count Harvey rotations starting 4 January 1900. From the measured perimeter, we are then able to fit a curve to the data and derive an area within the line of best fit. We observe the area of the northern polar hole area in 1996, at the beginning of solar cycle 23, to be about 4.2% of the total solar surface area and about 3.6% in 2007. The area of the southern polar hole is observed to be about 4.0% in 1996 and about 3.4% in 2007. Thus, both the north and south polar hole areas are no more than 15% smaller now than they were at the beginning of cycle 23. This compares to the polar magnetic field measured to be about 40% less now than it was a cycle ago.Comment: 18 pagers, 7 figures, accepted to Solar Physic