Several recent reports have suggested that the sperm counts of normal men are declining in most countries. In this study the sperm counts of Finnish men, and their possible changes during the past 28 years, were investigated. The material consisted of semen samples from 238 normal healthy men of unknown fertility and 5481 men from infertile couples. The means (medians) of semen volume, sperm density and total sperm count in normal men were 3.3 (3.0) ml, 133.9 (94.0) x 10(6)/ml and 396.6 (309.0) x 10(6), respectively. These parameters and the relative frequency distribution of the sperm density were similar to those reported elsewhere in the 1940s. Multiple linear regression analysis revealed a significant decrease in semen volume, whereas sperm density and total sperm count of infertile men had not changed significantly during the past 28 years. In addition, no change in sperm counts was associated with the year of men's birth.

Millions of wild animals are killed annually on roads worldwide. During spring 2020, the volume of road traffic was reduced globally as a consequence of the COVID-19 pandemic. We gathered data on wildlife-vehicle collisions (WVC) from Czechia, Estonia, Finland, Hungary, Israel, Norway, Slovenia, Spain, Sweden, and for Scotland and England within the United Kingdom. In all studied countries WVC statistics tend to be dominated by large mammals (various deer species and wild boar), while information on smaller mammals as well as birds are less well recorded. The expected number of WVC for 2020 was predicted on the basis of 2015–2019 WVC time series representing expected WVC numbers under normal traffic conditions. Then, the forecasted and reported WVC data were compared. The results indicate varying levels of WVC decrease between countries during the COVID-19 related traffic flow reduction (CRTR). While no significant change was determined in Sweden, where the state-wide response to COVID-19 was the least intensive, a decrease as marked as 37.4% was identified in Estonia. The greatest WVC decrease, more than 40%, was determined during the first weeks of CRTR for Estonia, Spain, Israel, and Czechia. Measures taken during spring 2020 allowed the survival of large numbers of wild animals which would have been killed under normal traffic conditions. The significant effects of even just a few weeks of reduced traffic, help to highlight the negative impacts of roads on wildlife mortality and the need to boost global efforts of wildlife conservation, including systematic gathering of roadkill data.

Four commonly used techniques for preparation of ' 4 C-labeled algal samples on membranes for liquid scintillation counting were compared and a simple technique for apparent net assimilation measurement from aqueous samples was introduced. All four techniques yielded similar radioactivities from the test cultures and are thus suitable for measurements of 4 C algal samples. The possibly carcinogenic solvent dioxane was not necessary with PCS scintillation cocktail for dissolving radioactivity from algae on filters.

Spontaneous abortions were analyzed in an industrial community in Finland in relation to the occupation of women and their husbands, and to the level of air pollution in the family's residential area. Information on abortions and births was obtained from the hospital discharge register; information on the women and their families was obtained from the files of the population and housing census. Women who were employed in rayon textile jobs and paper products jobs had an increased rate (P less than 0.10) of spontaneous abortions; the wives of men employed in transport and communication, in rayon textile jobs, and in chemical process jobs also had an increased rate of spontaneous abortions. In material stratified for age, parity, and socioeconomic class no evidence was found that the level of sulfur dioxide or carbon disulfide could be associated with a risk of spontaneous abortions. More spontaneous abortions were noted in all socioeconomic classes in areas where the mean annual level of hydrogen sulfide exceeded 4 micrograms m-3. However, the difference (total rates 7.6 and 9.3, respectively) was not significant statistically.

No abstract

The distribution of resistance to ampicillin, chloramphenicol, sulfonamides, tetracycline, and streptomycin among fecal coliforms in sewage, surface waters, and sea water was investigated. The incidence of resistant strains among isolates varied significantly among the water samples, without obvious connection with the water source or the level of pollution. The average frequency of multiple resistance was not always high in the same samples in which the overall resistance was high. The species composition varied considerably in different water samples. A significant correlation was observed between the relative frequency of Klebsiella species and the incidence of ampicillin resistance in water samples. The importance of species composition of fecal coliforms, affected by their source and by the aquatic environment, on the resistance pattern is noted.

No abstract

The effect of testosterone propionate on cell renewal rate and mitotic cycle of castrated mice was investigated. 0.25 mg of the hormone was given thrice at 24 h intervals and 50 μc of 3H-thymidine was injected simultaneously with the last hormone injection. After this the mice were killed at 1 to 2 h intervals. Ventral prostates and seminal vesicles were weighed and the thymidine incorporation into their epithelia determined in radioautograms. A piece of proximal small intestine was used as reference tissue. The labelling index in the castrated control animals was 1.3 for the seminal vesicle; 68 h after testosterone treatment it was 44. The figures for the ventral prostate were 1.9 and 37, and for the small intestine 44 and 57. The mitotic index in the prostate of the experimental animals and that in the intestine of all the animals was 0.5; in the seminal vesicle it was 0.4. The mitotic index in the accessory glands of the control mice was very low. The specific activity of DNA per nucleus was higher in the hormone treated than in the control animals. The cell cycle (TC) in the prostate was shortened from about 900 h to 20 h after testosterone. The synthetic phase (TS) was shortened from 16 to 7 h, presynthetic (TG1) phase from 900 to 10 h, whereas the postsynthetic phase (TG2) remained unchanged. The corresponding figures for the seminal vesicle were: TG2 from 4.5 to 0.5 h, TS from 12 to 7 h, TG1 from 900 to 10 h and TC from 900 to 18 h. The changes in the intestinal epithelium were less marked: TC from 22 to 16 h, TS from 8.5 to 8 h, TG1 from 12 to 6 h, while TG2 remained unchanged.