Variation in forest area on the Central Russian Upland within the last 250 years

The variation in percentage of forested area in the zones of broadleaved forests and forest steppe on the Central Russian Upland is investigated on the basis of historical maps of the 18th–20th centuries and modern cosmic photographs. The distribution pattern of forests on the upland remains rather stable within the last 250 years, and an insignificant tendency for a decrease in the forest area is seen. Changes in forests are revealed in some regions. Forest destruction is intensive near the former tree entanglements of the 16th and 17th centuries, and analysis of their succession in the period of the 18th–20th centuries allows us to model the forested area on the Central Russian Upland by the start of the area development. Forest regeneration within the last 100-year-long period is seen in the basin of the upper reaches of the Oka River.     

Rabies in Tunisia. A comparative study of results from the last 36 years

The author presents an evaluation of rabies control during the last 36 years. He discusses especially the problem of vectors, diagnosis, vaccine and treatment, taking into account the 1982-1987 National Campaign for Animal Rabies Control. He notes an improvement of the situation with a significant decrease in the rate of positivity among the biter animals. He considers, however that this rate remains relatively too high to allow the prevention of disease persitance in the country. He suggests the continuation of the efforts undertaken to control biter animals and eventually the extension of the campaign to the regional level.     

Changes in the sexual dimorphism of the human mandible during the last 1200 years in Central Europe

According to many investigations, changes in mandibular morphology can occur synchronously with changes in the environment, and sexual dimorphism of the mandible can be influenced by the environment. Sexual dimorphism during the last 1200 years was evaluated using geometric morphometric analysis of virtual cranial models. The method of geometric morphometrics allows differences in size and shape to be assessed separately. We analyzed groups of adult individuals dating to Early Middle Ages, High Middle Ages, Early Modern Ages and from a modern Czech population (21st century). Significant sexual dimorphism in mandibular size was found in all populations. A trend in the sexual dimorphism of size was seen, with differences between the sexes increasing gradually over time. Size changes in female mandibles were a better reflection of environmental conditions and climate than size changes in male mandibles. Regarding changes in the sexual dimorphism of shape, significant dimorphism was found in all four samples. However, the pattern of mandibular shape dimorphism was different and varied considerably between samples. There was only one stable shape trait showing sexual dimorphism across all four samples in our study: the gonion lies more laterally in male than in female mandibles and male mandibles are relatively wider than female mandibles. Sexual dimorphism of shape is not influenced by the climate; instead sexual selection might play a role. This research supports earlier studies that have found that the degree and pattern of sexual dimorphism is population-specific and the factors regulating sexual dimorphism today may not be the same as those in the past.     

Minor changes in orthopteran assemblages of Central European protected dry grasslands during the last 40 years

During the past 50 years development of farming practices caused tremendous changes in European agricultural landscapes and many insect species became increasingly restricted to protected areas. Yet little is known about long-term trends of insect diversity and community composition in these often small reserves. We performed a comparative study on changes in orthopteran communities of protected dry grasslands in East Germany, which had been surveyed in the 1960s. Applying the same sampling techniques, we revisited 26 of the original sites in 2008 and 2009. Nearly all sites are controlled by conservation policies and changes in vegetation composition were relatively small, although some sites showed shrub encroachment. Changes in orthopteran diversity were not significant. Community composition showed minor changes which were correlated with evidence of woody plant encroachment as derived from historical and recent aerial imagery. The frequency of some Caelifera species decreased from the 1960s to 2008/2009 with one species inhabiting bare soils (Myrmeleotettix maculatus) showing the strongest decline. Some Ensifera, especially two species inhabiting open woodland and scrub (Tettigonia viridissima, Phaneroptera falcata) showed positive trends. Nevertheless, three different regions (each belonging to a different German federal state) had shown distinct orthopteran assemblages in the 1960s, and these were equally different 40 years later. We conclude that the orthopteran fauna of Central European protected dry grasslands showed small changes in species composition, and overall diversity remained rather constant during the past 40 years, which is in accordance with the minor changes in the surrounding landscape. Consequently, the applied conservation management practises—mainly sheep grazing and trimming—are largely effective.     

The pathogenesis of endemic fluorosis: Research progress in the last 5 years

Fluorine is one of the trace elements necessary for health. It has many physiological functions, and participates in normal metabolism. However, fluorine has paradoxical effects on the body. Many studies have shown that tissues and organs of humans and animals appear to suffer different degrees of damage after long‐term direct or indirect exposure to more fluoride than required to meet the physiological demand. Although the aetiology of endemic fluorosis is clear, its specific pathogenesis is inconclusive. In the past 5 years, many researchers have conducted in‐depth studies into the pathogenesis of endemic fluorosis. Research in the areas of fluoride‐induced stress pathways, signalling pathways and apoptosis has provided further extensive knowledge at the molecular and genetic level. In this article, we summarize the main results.     

Central serotonergic hypofunction in autism: results of the 5-hydroxy-tryptophan challenge test

Some studies have suggested that disorders in the central serotonergic function may play a role in the pathophysiology of autistic disorder. In order to assess the central serotonergic turnover in autism, this study examines the cortisol and prolactin responses to administration of L-5-hydroxy-tryptophan (5-HTP), the direct precursor of 5-HT in 18 male, post-pubertal, Caucasian autistic patients (age 13-19 y.; I.Q.>55) and 22 matched healthy volunteers. Serum cortisol and prolactin were determined 45 and 30 minutes before administration of 5-HTP (4 mg/kg in non enteric-coated tablets) or an identical placebo in a single blind order and, thereafter, every 30 minutes over a 3-hour period. The 5-HTP-induced increases in serum cortisol were significantly lower in autistic patients than in controls, whereas there were no significant differences in 5-HTP-induced prolactin responses between both study groups. In baseline conditions, no significant differences were found in serum cortisol and prolactin between autistic and normal children. The results suggest that autism is accompanied by a central serotonergic hypoactivity and that the latter could play a role in the pathophysiology of autism.