Number Of Km Research Articles

Professional drivers and cardiovascular risk: APPTIV cohort

Abstract Background Professional drivers have a high risk of morbidity, including myocardial infarction. Bus, taxi and truck drivers have most often constituted the studied populations. However, if the transport sector faces road risk, 70% of employees in all activity sectors are exposed to this risk in France. Most often studied by the analysis of global working time, the real driving time and the distance travelled are rarely taken into account, whereas they are potentially modifiable factors. Purpose To assess the associations between exposure to road risk by taking into account driving time and the number of kilometers travelled professionally and certain cardiovascular risk factors, in different sectors of professional activity. Method Based on the APPTIV cohort, data from 984 men and women employees from 94 companies in France was collected from 2018 to 2019, during occupational health medical visits focused on road risk. The number of Kms / month (<400 (ref); <1600; ≥1600) and the duration of driving (hours / d <1 (ref); <4; ≥4) were studied according to the respective tertiles. A variable with 9 classes was created. Logistic regressions adjusted for age, gender and activity sectors were carried out to explain the associations with certain cardiovascular factors (Hypertension, overweight (≥25 kg/m2), obesity (30 kg/m2) Hypertriglyceridemia (≥1.7 mmol/l), Hypercholesterolemia, HypoHDLemia). Results The population studied came from 23.30% of the transport sector, 23.30% of the construction sector, 26.75 of the public administration and 4.78% of the trade sector. After adjustments, the estimated risks of hypertension according to the driving time or the number of km travelled are not significant. Driving between 1 and 4 hours and more than 4 hours per day increases the risk of obesity, by: OR: 1.85 (1.22–2.80); 1.85 (1.19–2.86), the risk of hypertriglyceridemia of 1.39 (1.0–1.95); 1.54 (1.09–2.18). Traveling more than 1600 km / m increases the risk of hypertriglyceridemia by 1.5. People driving between 400 and 1600 km / m with a driving time between 1 and 4 h / d or those covering more than 1600 km with long driving times (>4 h / d) have an estimated risk of obesity at 1.82 (1.05–3.14) and 1.87 (1.13–3.11) respectively. Those traveling over 1600 km / m with long driving times (>4 hrs / day) have a 1.5 times risk of hypertriglyceridemia. Conclusion Taking into account the number of hours of driving and the kilometers travelled professionally, this study highlighted some employee profiles with high cardiovascular risk, accessible to medical and professional prevention measures. Funding Acknowledgement Type of funding source: None

Spread of Ebola virus disease based on the density of roads in West Africa.

On March 23rd 2014 the World Health Organization announced that a new Ebola outbreak had appeared in West Africa involving three countries. The objective of this study was to show how a road density index (RDI) could be constructed and a study of its association with Ebola cases during the outbreak. The study was carried out at the district level across the affected countries. RDI was calculated by km2 of territory as a proxy for the mobility of the population. To calculate this index, the number of km of road constructed in each district was estimated and subsequently divided by the area of each district expressed in km2. The accumulated incidence of Ebola was calculated per district. A generalised linear model with a Poisson distribution was used. The RDI varied from 0.12 to 0.84 between the districts. An RDI increase of 0.01 indicates a 3% increase in Ebola infection risk (RR is 1.03; CI 1.03-1.04). The density of the road network can influence the increased incidence of Ebola cases in the affected zone. An exhaustive mapping of the area could help the relevant organisations to manage another outbreak in the future and it could help the distribution of resources in an emergency situation.

A number theoretic problem on super line graphs

In Bagga et al. (1995) a generalization of the line graph concept was introduced. Given a graph G with at least r edges, the super line graph of indexr, Lr(G), has as its vertices the sets of r edges of G, with two adjacent if there is an edge in one set adjacent to an edge in the other set. The line completion numberlc(G) of a graph G is the least index r for which Lr(G) is complete. In this paper we investigate the line completion number of Km,n. This turns out to be an interesting optimization problem in number theory, with results depending on the parities of m and n. If m≤n and m is a fixed even number, then lc(Km,n) has been found for all even values of n and for all but finitely many odd values. However, when m is odd, the exact value of lc(Km,n) has been found in relatively few cases, and the main results concern lower bounds for the parameter. Thus, the general problem is still open, with about half of the cases unsettled.

The crossing number of the Cartesian product of paths with complete graphs

In this paper, we determine the crossing number of Km∖e by the construction method for m≤12 and apply the zip product to obtain that cr(Km□Pn)=(n−1)cr(Km+2∖e)+2cr(Km+1) for n≥1. Furthermore, we have cr(Km□Pn)=14⌊m+12⌋⌊m−12⌋⌊m−22⌋(n⌊m+42⌋+⌊m−42⌋) for n≥1, 1≤m≤10, which is consistent with Zheng’s conjecture for the crossing number of Km□Pn.

Daily hyperhydration effect on electrolyte deficiency of endurance-trained subjects during prolonged hypokinesia.

The aim of this study was to evaluate the effect of a daily intake of fluid and salt supplementation (FSS) on the deficiency of electrolytes, which is characterized by higher rather than lower plasma concentration of electrolytes during prolonged hypokinesia (HK) (decreased number of km taken per day). Forty long distance runners aged 22-25 yr with a peak VO2 65.4 mL min(-1) kg(-1) with an average 14.2 km d running distance were selected as subjects. They were equally divided into four groups: 1) unsupplemented control subjects (UCS); 2) unsupplemented hypokinetic subjects (UHS); 3) supplemented hypokinetic subjects (SHS), and 4) supplemented control subjects (SCS). During the investigation of 364 d, groups 2 and 3 maintained an average running distance of less than 4.7 km per day, groups 1 and 4 did not experience any modification in their normal training routines and diets. During the preexperimental period of 60 d and during the experimental period of 364 d urinary excretion of electrolytes and concentrations of sodium, potassium, calcium, and magnesium in plasma were determined. Whole blood hemoglobin, hematocrit index, plasma osmolality, and plasma protein concentration were measured. In the UHS plasma concentration of electrolytes and urinary excretion thereof, fluid elimination, hematocrit, whole blood hemoglobin, plasma osmolality, and plasma protein concentration increased significantly (p < 0.05) when compared with the UCS, SCS, and SHS groups. In the SHS plasma concentration of electrolytes and urinary excretion thereof, fluid excretion, whole blood hemoglobin, hematocrit, plasma osmolality, and plasma protein concentration decreased when compared with the UHS and increased insignificantly when compared with the UCS and SCS groups. It was concluded that FSS may be used to prevent or minimize electrolyte deficiency in endurance-trained volunteers during prolonged restriction of muscular activity.

Fluid-electrolyte changes in physically conditioned subjects after hypokinesia and chronic hyperhydration

The aim of this study was to determine whether fluid-electrolyte changes, which are developed during prolonged hypokinesia (decreased number of km per day), can be prevented or minimized with the use of a daily intake of fluid and salt supplementation (FSS). The experiments on hypokinesia (HK) were performed for 364 days on 18 endurance-trained male volunteers in the age range of 21–23 years, with an average maximum oxygen uptake of 67 ml kg −1. All volunteers were divided into three equal groups: six volunteers were placed on a continuous regime of exercise of 14.0 km day −1 and served as control subjects. Six volunteers were subjected to continuous HK without FSS and were considered as the unsupplemented hypokinetic subjects (UHS). The remaining volunteers were under continuous HK and FSS and were considered as the supplemented hypokinetic subjects (SHS). For the simulation of the hypokinetic effect, the UHS and SHS groups were kept continuously under an average of 2.7 km day −1 for the duration of the experiment. Prior to exposure to HK, all volunteers were on the same exercise regime as the controls. During the pre-experimental period of 60 days and during the post-experimental period, urinary excretion of electrolytes and concentrations of sodium, potassium, calcium and magnesium in serum as well as serum osmolality were determined. An increased renal excretion of fluid and electrolytes and a decreased serum electrolyte concentration were observed in the SHS, while a decreased renal excretion of fluid and electrolytes and an increased serum electrolyte concentration were observed in the UHS, during the initial stages of the post-hypokinetic period. By day 30 of the post-hypokinetic period these changes were reverted back to the control levels. We concluded that chronic hyperhydration may be used to attenuate urinary and serum electrolyte changes in endurance-trained volunteers after exposure to prolonged HK.

Expression of a downstream gene from a bicistronic transcription unit in transgenic tobacco plants

We have constructed a set of plasmids carrying an artificial compact stop-start codon sequence, TGA TG TAA CATGA, between an upstream open reading frame, terminating at one of the stop codons, and a downstream kanamycin-resistance (Km R)-encoding gene ( nptII) initiating at the second ATG. These plasmids were introduced into tobacco protoplasts by direct gene transfer. The efficiency of expression of the downstream nptII gene was measured by scoring the number of Km R transformants. With a closer distance between the functional stop and start codons, a tendency to less efficient expression of nptII was found. The integration and expression of both genes as a bicistronic transcription unit were verified by Southern- and Northern-blot analyses. A possible application of the compact stop-start codon sequence for insertional mutagenesis is discussed.

Molecular evidence for interchromosomal recombination in the cyanobacterium Synechocystis sp. PCC 6803

Experiments dealing with the regulation of psbA-I gene expression in Synechocystis 6803 have produced results that indicate interchromosomal recombination events. A kanamycin resistance reporter gene (Km R) was inserted within the psbA-I structural gene, and a chloramphenicol resistance gene (Cm R) coupled to an origin of replication for E. coli was added downstream to the Km R reporter, thus allowing rescue of this entire DNA region. Transformation of wild-type (WT) Synechocystis 6803 cells with this plasmid produced only very few Km R transformants. However, random deletions in the region between the putative psbA-I promoter and the Km R reporter led to a marked increase in the number of Km R transformants obtained. Plasmids, rescued from such transformants, were used for secondary transformations. The rescued plasmids were consistently effective in rendering Km R. Moreover, the transformants were found to contain two distinct chromosomal configurations; one containing the deletion as opposed to the other which remained intact. Molecular analysis of the various Km R transformants suggests a series of interchromosomal recombinations, a model for which is provided.

Kinetic analysis of Escherichia coli RNase H using DNA-RNA-DNA/DNA substrates.

The kinetic properties of Escherichia coli ribonuclease H (RNase H) were investigated using oligonucleotide substrates that consist of a short stretch of RNA, flanked on either side by DNA (DNA-RNA-DNA). In the presence of a complementary DNA strand, RNase H cleavage is restricted to the short ribonucleotide stretch of the DNA/RNA heteroduplex. The DNA-RNA-DNA substrate utilized for kinetic studies: (formula; see text) is cleaved at a single site (decreases) in the presence of a complementary DNA strand, to generate (dT)7-(rA)2-OH and p-(rA)2-(dT)9. Anion exchange high performance liquid chromatography was used to separate and quantitate the cleavage products. Under these conditions, RNase H-specific and nonspecific degradation products could be resolved. Kinetic parameters were measured under conditions of 100% hybrid formation (1.2-1.5 molar excess of complementary DNA, T much less than Tm). A linear double reciprocal plot was obtained, yielding a Km of 4.2 microM and a turnover number of 7.1 cleavages per s per RNase H monomer. The kinetic properties of substrate analogs containing varying lengths of RNA (n = 3-5) and 2'-O-methyl modifications were also investigated. Maximal turnover was observed with DNA-RNA-DNA substrates containing a minimum of four RNA residues. Kcat for the rA3 derivative was decreased by more than 100-fold. The Km appeared to decrease with the size of the internal RNA stretch (n = 3-5). No significant difference in turnover number of Km was observed when the flanking DNA was replaced with 2'-O-methyl RNA, suggesting that RNase H does not interact with this region of the heteroduplex.

Intensities of weak lines at the solar limb

From the observations, made with a slitless spectrograph and which were standardized by means of the light from the centre of the Sun’s disk, the line strengths were determined in absolute units. For the absorption lines this strength means the amount of radiation missing from the continuous spectrum because of the presence of the absorption line. For emission links it has the usual meaning. All absolute intensities given here are integrated ones, as observed with the slitless spectrograph and refer to the radiation from a slice of 1 cm width, through photosphere and chromosphere, parallel to the dispersion in the spectrum, extending outwards from the level where the Moon’s limb is projected, expressed in 1014 ergs per set per sterad per Angstrom. In Fig. 1 the intensity is plotted for the line Fe 4611.295 A and in this case the equivalent width is given too. The value of the equivalent width in the centre of the Sun is indicated at 131 mA, which value is taken from the Utrecht Catalogue.(2) This line is by far the strongest line treated in this communication, but by means of the curves in Fig. 1, the absolute intensities of the lines in the next figures can be transformed to equivalent widths. This is so because the absolute intensity in the solar spectrum in the wavelength region covered, is constant within 1 per cent.‘3) In all our figures the solar limb is placed as weil as possible, in the position determined by DE GROOT’~) from photoelectric measurements during the same eclipse. The relation between the scales of r,), the number of km within the Sun’s limb and the time in which the Moon’s edge moved over a certain distance, is indicated in Fig. 7 along the abscissa. In Fig. 2 absolute intensities of a number of Fe lines are given. The decrease of the