Theories of Nomadic Movement: A New Theoretical Approach for Understanding the Movement Decisions of Nenets and Komi Reindeer Herders

It is known that the relationship between humans and their animals is important for understanding many aspects of nomadic pastoralist systems, including nomadic movement. However, to date, these complex human–animal relations have not been analyzed in a way that has led to an explanatory model of nomadic movement capable of producing testable hypotheses. Based on ethnographic material collected amongst Komi and Nenets nomadic reindeer herders of the Russian Arctic, we argue that nomadic movements can be best understood as a product of the interplay that exists between animal behaviour and the herders’ skilful actions to (a) maintain herd cohesion and (b) avoid hazards, whilst deploying the minimum amount of resources (i.e., human/animal effort and use of equipment) on rounding up the herd, stopping and turning it. Ecological factors affect movement through their influence on animal behaviour, whereas non-ecological factors do so by influencing the herders’ skilful actions. We demonstrate that, based on these assumptions, it is possible to build a testable model explaining the movement of some nomadic groups.

Comparable Long-Term Efficacy of Lopinavir/Ritonavir and Similar Drug-Resistance Profiles in Different HIV-1 Subtypes

Background

Analysis of potentially different impact of Lopinavir/Ritonavir (LPV/r) on non-B subtypes is confounded by dissimilarities in the conditions existing in different countries. We retrospectively compared its impact on populations infected with subtypes B and C in Israel, where patients infected with different subtypes receive the same treatment.

Methods

Clinical and demographic data were reported by physicians. Resistance was tested after treatment failure. Statistical analyses were conducted using SPSS.

Results

607 LPV/r treated patients (365 male) were included. 139 had HIV subtype B, 391 C, and 77 other subtypes. At study end 429 (71%) were receiving LPV/r. No significant differences in PI treatment history and in median viral-load (VL) at treatment initiation and termination existed between subtypes. MSM discontinued LPV/r more often than others even when the virologic outcome was good (p = 0.001). VL was below detection level in 81% of patients for whom LPV/r was first PI and in 67% when it was second (P = 0.001). Median VL decrease from baseline was 1.9±0.1 logs and was not significantly associated with subtype. Median CD4 increase was: 162 and 92cells/µl, respectively, for patients receiving LPV/r as first and second PI (P = 0.001), and 175 and 98, respectively, for subtypes B and C (P<0.001). Only 52 (22%) of 237 patients genotyped while under LPV/r were fully resistant to the drug; 12(5%) were partially resistant. In48%, population sequencing did not reveal resistance to any drug notwithstanding the virologic failure. No difference was found in the rates of resistance development between B and C (p = 0.16).

Conclusions

Treatment with LPV/r appeared efficient and tolerable in both subtypes, B and C, but CD4 recovery was significantly better in virologically suppressed subtype-B patients. In both subtypes, LPV/r was more beneficial when given as first PI. Mostly, reasons other than resistance development caused discontinuation of treatment.     

Trichinellosis of animals in Chukotka, USSR: A general review

During an examination, for trichinellosis, of 1489 mammals of 12 different species, in the territory of Chukotka National district (regions of Anadyr', Bering, Iul'tin, Chaun and Chukotka) and in the region of North-Even of Magadan province, Trichinella larvae were detected in 236 (16·4%) of these animals from 6 of the species: in 109 (44·8%) of the blue polar foxes kept in cages, in 12 (15·8%) of the silver-black foxes kept in cages, in 84 (18·2%) of the white polar foxes, in 17 (17·5%) of the common foxes, in 13 (12·1%) of the dogs and in the one European bear examined. Trichinella larvae were not found in 190 marine mammals examined: 178 ringed seals, 7 whales, 4 walruses, and 1 bearded seal, nor in the 8 Siberian squirrels and 159 domestic pigs examined. The high incidence of Trichinella infection amongst blue polar foxes and silver-black foxes on fur-animal farms in Chukotka, where the food ration of these animals is predominately the flesh of marine mammals (walruses and other pinnipeds), suggests that marine mammals may constitute one of the sources of infection to caged animals. In Chukotka, as in other regions of the Extreme North and North-East, the circulation of trichinae in nature may occur between two ecologically different groups of animals: terrestial and marine mammals. A wide distribution of trichinellosis among animals in nature, or kept in cages and among dogs in Chukotka National district and in the North-Even region of Magadan province provides a constant threat of infection to man. Thus the flesh and sub-products of potential hosts of trichinae (including dogs, fur animals, European and polar bears, marine mammals, etc.) should undergo thorough trichinelloscopy examination before being consumed by man. The flesh of sea mammals should be examined for trichinellosis before being used as food for animals; the presence of trichinae in it requires its sterilization.     

Magnetophoresis and the magnetic susceptibility of HeLa tumor cells

A method for measuring the magnetic susceptibility of a single cell is developed and theoretically justified. The method is based on use of a computer-aided video recording of the integral curve of magnetophoretic motion of a cell settling in liquid medium near a thin vertical magnetic rod under the influence of a uniform magnetic field. The magnetic susceptibility of HeLa tumor cells and nutrient medium 199 is measured.     

Sensitivity to levofloxacin of Mycobacterium tuberculosis strains with various phenotype isolated from patients with newly diagnosed and chronic tuberculosis]

Susceptibility to levofloxacin of 56 strains of Mycobacterium tuberculosis, isolated from 22 patients with first estimated and 84 patients with chronic tuberculosis was investigated. Ratio of multi-drug resistance achieved 54.5 per cent in first group and 94.1 per cent in the second group. 23 (41.1 per cent) isolated strains belonged to individual genotypes, 33 (58.9 per cent)--to Beijing group. All mycobacteria isolates were sensitive to critical concentration of levofloxacin--10 mcg/mL. The results of the investigation proves the ability to recommend levofloxacin application at the patients with first estimated tuberculosis and at the patients with most hazardous tuberculosis pathogen of Beijing group.     

Magnetophoresis and magnetic susceptibility of HeLa tumor cells

A method for measuring the magnetic susceptibility of separate cells has been theoretically developed and implemented in experiments. It is based on fitting the videocomputer and predicted data for the integral motion curve of cells that settle in a fluid along a thin ferromagnetic bar by the action of a uniform magnetic field. The magnetic susceptibility of HeLa tumor cells and culture medium 199 has been measured.     

Plasma asymmetric dipole antenna excited by a surface wave

A study is made of a quarter-wave asymmetric dipole antenna in which the conducting rod is replaced by a plasma column with an electron density much higher than the critical density. The parameters of such an antenna are determined by the exited surface wave, which affects the electromagnetic field structure in the near-field zone. It is shown analytically, numerically, and experimentally that the resonant length of the plasma dipole antenna is close to one-quarter of the length of the surface wav and that the conversion efficiency of plasma antenna power into radiation can be no worse than that of a metal dipole antenna. It is also shown experimentally that the plasma in a dipole antenna can be self-consistently excited by an RF oscillator and that the excited RF oscillations can be efficiently radiated into the surrounding space.     

Changes in the dehydrogenase activity of cardiomyocytes during acute experimental arterial occlusion of extremities

The results of quantitative histoenzymologic investigations of succinate dehydrogenase, lactate dehydrogenase and NAD-diaphorase in cardiomyocytes of dogs with acute experimental arterial occlusion in ischemic and postischemic periods are reviewed. An increased activity of dehydrogenases in the early periods (3,6 h) of ischemia and during recirculation was established, with its noticeable reduction at later terms (9,12 h). Medical correction of postischemic disorders was shown to improve cardiomyocyte metabolism.