584 research outputs found
Bacterial community profiles and Vibrio parahaemolyticus abundance in individual oysters and their association with estuarine ecology
Oysters naturally harbor the human gastric pathogen Vibrio parahaemolyticus, but the nature of this association is unknown. Because microbial interactions could influence the accumulation of V. parahaemolyticus in oysters, we investigated the composition of the microbiome in water and oysters at two ecologically unique sites in the Great Bay Estuary, New Hampshire using 16s rRNA profiling. We then evaluated correlations between bacteria inhabiting the oyster with V. parahaemolyticus abundance quantified using a most probable number (MPN) analysis. Even though oysters filter-feed, their microbiomes were not a direct snapshot of the bacterial community in overlaying water, suggesting they selectively accumulate some bacterial phyla. The microbiome of individual oysters harvested more centrally in the bay were relatively more similar to each other and had fewer unique phylotypes, but overall more taxonomic and metabolic diversity, than the microbiomes from tributary-harvested oysters that were individually more variable with lower taxonomic and metabolic diversity. Oysters harvested from the same location varied in V. parahaemolyticus abundance, with the highest abundance oysters collected from one location. This study, which to our knowledge is the first of its kind to evaluate associations of V. parahaemolyticus abundance with members of individual oyster microbiomes, implies that sufficient sampling and depth of sequencing may reveal microbiome members that could impact V. parahaemolyticus abundance
Game-theoretic versions of strong law of large numbers for unbounded variables
We consider strong law of large numbers (SLLN) in the framework of
game-theoretic probability of Shafer and Vovk (2001). We prove several versions
of SLLN for the case that Reality's moves are unbounded. Our game-theoretic
versions of SLLN largely correspond to standard measure-theoretic results.
However game-theoretic proofs are different from measure-theoretic ones in the
explicit consideration of various hedges. In measure-theoretic proofs existence
of moments are assumed, whereas in our game-theoretic proofs we assume
availability of various hedges to Skeptic for finite prices
Rehospitalizacje w niewydolności serca z upośledzoną funkcją lewej komory — strategie zapobiegania
Niewydolność serca (HF) w krajach rozwiniętych dotyczy ponad 10% populacji powyżej 70. roku życia, stanowiąc tym samym ważny problem zarówno zdrowotny, społeczny, jak i ekonomiczny. Szacuje się, że obecnie w Polsce na HF cierpi 600 000–700 000 osób. Mimo postępu, jaki się dokonał w ostatnich 30 latach w zakresie farmakoterapii niewydolności serca z istotnie upośledzoną funkcją skurczową lewej komory (HFrEF) (wdrożenie inhibitorów konwertazy angiotensyny [ACEI], blokerów receptora angiotensyny II [ARB], antagonistów receptora mineralokortykoidowgo [MRA] oraz iwabradyny) rokowanie pacjentów z tej grupy pozostaje niekorzystne. Jednym z głównych czynników istotnie zwiększających współczynnik śmiertelności w tej grupie chorych jest wysoki odsetek ponownych hospitalizacji (w ciągu roku dla ostrej HF — 43,9%; dla przewlekłej HF — 31,9%). Tym samym HF stanowi również wiodącą przyczynę rehospitalizacji pacjentów powyżej 65. roku życia. W sytuacji nadmiernego obciążenia oddziałów kardiologicznych i niedostatecznego finansowania hospitalizacji pacjentów z HF istnieje bardzo duże niebezpieczeństwo skracania okresu pobytu w szpitalu poniżej bezpiecznego minimum. Przy czym powszechny i wczesny dostęp do kardiologa wciąż stanowi problem dla wielu pacjentów z HF. W efekcie wczesne rehospitalizacje są w wielu przypadkach wynikiem nieoptymalnego wyrównania w trakcie hospitalizacji, utrudnionego wczesnego dostępu do specjalisty po wypisaniu ze szpitala, a także braku sprecyzowanego planu dalszej opieki ambulatoryjnej zarówno w zakresie terminu najbliższej wizyty, jak i eskalacji farmakoterapii. Świadomość problemów codziennej opieki nad pacjentem z HFrEF oraz czynników ryzyka rehospitalizacji i gorszego rokowania może stanowić nieocenioną pomoc w wyłonieniu z szerokiej grupy chorych z HFrEF tych, którzy wymagają wzmożonej czujności i częstszych kontroli w poradni specjalistycznej
Molecular interaction between bacterial antigens and macrophage receptors studied by atomic force microscopy
Atomic force spectroscopy was used to study interaction strengths between bacterial antigens and receptors on macrophages. This method allowed for a direct comparison of the interaction strengths in different systems studied at the level of single molecules
Assessment of pathological response to therapy using lipid mass spectrometry imaging.
In many cancers, the establishment of a patient's future treatment regime often relies on histopathological assessment of tumor tissue specimens in order to determine the extent of the 'pathological response' to a given therapy. However, histopathological assessment of pathological response remains subjective. Here we use MALDI mass spectrometry imaging to generate lipid signatures from colorectal cancer liver metastasis specimens resected from patients preoperatively treated with chemotherapy. Using these signatures we obtained a unique pathological response score that correlates with prognosis. In addition, we identify single lipid moieties that are overexpressed in different histopathological features of the tumor, which have potential as new biomarkers for assessing response to therapy. These data show that computational methods, focusing on the lipidome, can be used to determine prognostic markers for response to chemotherapy and may potentially improve risk assessment and patient care
Temperature-driven single-valley Dirac fermions in HgTe quantum wells
We report on temperature-dependent magnetospectroscopy of two HgTe/CdHgTe
quantum wells below and above the critical well thickness . Our results,
obtained in magnetic fields up to 16 T and temperature range from 2 K to 150 K,
clearly indicate a change of the band-gap energy with temperature. The quantum
well wider than evidences a temperature-driven transition from
topological insulator to semiconductor phases. At the critical temperature of
90 K, the merging of inter- and intra-band transitions in weak magnetic fields
clearly specifies the formation of gapless state, revealing the appearance of
single-valley massless Dirac fermions with velocity of
ms. For both quantum wells, the energies extracted from
experimental data are in good agreement with calculations on the basis of the
8-band Kane Hamiltonian with temperature-dependent parameters.Comment: 5 pages, 3 figures and Supplemental Materials (4 pages
Temperature-dependent magnetospectroscopy of HgTe quantum wells
We report on magnetospectroscopy of HgTe quantum wells in magnetic fields up
to 45 T in temperature range from 4.2 K up to 185 K. We observe intra- and
inter-band transitions from zero-mode Landau levels, which split from the
bottom conduction and upper valence subbands, and merge under the applied
magnetic field. To describe experimental results, realistic
temperature-dependent calculations of Landau levels have been performed. We
show that although our samples are topological insulators at low temperatures
only, the signature of such phase persists in optical transitions at high
temperatures and high magnetic fields. Our results demonstrate that
temperature-dependent magnetospectroscopy is a powerful tool to discriminate
trivial and topological insulator phases in HgTe quantum wells
Almost-Euclidean subspaces of via tensor products: a simple approach to randomness reduction
It has been known since 1970's that the N-dimensional -space contains
nearly Euclidean subspaces whose dimension is . However, proofs of
existence of such subspaces were probabilistic, hence non-constructive, which
made the results not-quite-suitable for subsequently discovered applications to
high-dimensional nearest neighbor search, error-correcting codes over the
reals, compressive sensing and other computational problems. In this paper we
present a "low-tech" scheme which, for any , allows to exhibit nearly
Euclidean -dimensional subspaces of while using only
random bits. Our results extend and complement (particularly) recent work
by Guruswami-Lee-Wigderson. Characteristic features of our approach include (1)
simplicity (we use only tensor products) and (2) yielding "almost Euclidean"
subspaces with arbitrarily small distortions.Comment: 11 pages; title change, abstract and references added, other minor
change
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