On determination of statistical properties of spectra from parametric level dynamics

We analyze an approach aiming at determining statistical properties of spectra of time-periodic quantum chaotic system based on the parameter dynamics of their quasienergies. In particular we show that application of the methods of statistical physics, proposed previously in the literature, taking into account appropriate integrals of motion of the parametric dynamics is fully justified, even if the used integrals of motion do not determine the invariant manifold in a unique way. The indetermination of the manifold is removed by applying Dirac's theory of constrained Hamiltonian systems and imposing appropriate primary, first-class constraints and a gauge transformation generated by them in the standard way. The obtained results close the gap in the whole reasoning aiming at understanding statistical properties of spectra in terms of parametric dynamics.Comment: 9 pages without figure

Ecological and hydrological values of small water reservoirs in the Białowieża Forest

W ostatnich latach na terenie Puszczy Białowieskiej notuje się stałe obniżanie się zwierciadła wód gruntowych. Proces ten jest spowodowany m.in. pracami melioracyjnymi wykonanymi w latach 50. i 60. ubiegłego wieku. Regulacja cieków oraz budowa rowów melioracyjnych przyśpieszyły odpływ wody. Efektem zaburzenia warunków wodnych na tym obszarze jest przesuszenie mokradłowych siedlisk leśnych, a w rezultacie grądowienie olsów i łęgów. W celu poprawy warunków wodnych mokradłowych obszarów leśnych na terenie Puszczy Białowieskiej (poza obszarem parku narodowego), z inicjatywy PTOP (Północnopodlaskie Towarzystwo Ochrony Ptaków), wybudowano kilkadziesiąt małych zbiorników wodnych różnych typów. Zbiorniki w zlewniach zalesionych powstały poprzez przegrodzenie naturalnych cieków bądź rowów progiem-bystrotokiem, natomiast zbiorniki śródpolne wykopano. Oczekuje się, że powyższe działania wpłyną korzystnie na wydłużenie okresu stagnacji wód roztopowych, co zapobiegnie wysychaniu niektórych cieków w okresie lata. Umożliwią one również przywrócenie i powstanie nowych miejsc rozrodu płazów oraz utrzymanie bazy pokarmowej dla ptaków obszarów mokradłowych, m.in. bociana czarnego (Ciconia nigra L.). W pracy przedstawiono ocenę warunków ekologicznych i hydrologicznych zbiorników w zlewni Narewki. Przeprowadzono podstawowe pomiary jakości wody i stanu roślinności ekotopu oraz lustra wody wybranych zbiorników. W wielu przypadkach stwierdzono wkraczanie roślinności siedlisk mokradłowych oraz wypadanie gatunków grądowych i borowych. W okresie wiosennym zaobserwowano wykorzystanie stworzonych miejsc lęgowych przez płazy oraz obecność bociana czarnego (Ciconia nigra L.). W wyniku budowy małych zbiorników wodnych poprawiły się warunki do istnienia siedlisk olsowych i łęgowych.Constant decline of groundwater levels has recently been observed in the Białowieża Forest . This process is due to drainage which took place in the 1950s and 1960s. Regulation of watercourses and construction of drainage canals and ditches caused the increase of water discharge from the area and drying of wetland forest habitats: riparian forests and alder carr. In order to improve water conditions for wetland forests in the area of the Białowieża Forest (outside the Białowieża National Park ) several dozen small water reservoirs were built by PTOP (North-Podlasie Association of Bird Protection). Some of them were made by damming watercourses and the midfield ponds were just dug out. These actions were expected to prolong the stagnation period of melting waters in the bed of watercourses, to create breeding places for amphibians and to provide food resources for waterfowl like e.g. black stork (Ciconia nigra L.). The study was focussed on ecological and hydrological conditions of small water reservoirs in the Narewka river catchment. The paper presents the description of plants, which have overgrown water reservoirs and their neighbourhood, the size of reservoirs and basic analyses of water quality. In most cases typical species for wetlands forest were observed, which was the evidence for the improvement of hydrologic conditions for riparian forests and alder carr. Moreover, water reservoirs were inhabited by waterfowl and used as breeding places by amphibians

Age-related impairments of mobility associated with cobalt and other heavy metals: Data from NHANES 1999-2004

Exposure to heavy metals promotes oxidative stress and damage to cellular components, and may accelerate age-related disease and disability. Physical mobility is a validated biomarker of age-related disability and is predictive of hospitalization and mortality. Our study examined associations between selected heavy metals and impaired lower limb mobility in a representative older human population. Data for 1615 adults aged =60 yr from the National Health and Nutrition Examination Survey (NHANES) 1999 to 2004 were used to identify associations between urinary concentrations of 10 metals with self-reported and measured significant walking impairments. Models were adjusted for confounding factors, including smoking. In models adjusted for age, gender, and ethnicity, elevated levels of cadmium, cobalt, and uranium were associated with impairment of the ability to walk a quarter mile. In fully adjusted models, cobalt was the only metal that remained associated: the odds ratio (OR) for reporting walking problems with a 1-unit increase in logged cobalt concentration (µg/L) was 1.43 (95% CI 1.12 to 1.84). Cobalt was also the only metal associated with a significant increased measured time to walk a 20-ft course. In analyses of disease categories to explain the mobility finding, cobalt was associated with physician diagnosed arthritis (1-unit increase OR = 1.22 (95% CI 1.00 to 1.49). Low-level cobalt exposure, assessed through urinary concentrations of this essential heavy metal, may be a risk factor for age-related physical impairments. Independent replication is needed to confirm this association. Copyright © Taylor & Francis Group, LLC