551 research outputs found
Remote information concentration by GHZ state and by bound entangled state
We compare remote information concentration by a maximally entangled GHZ
state with by an unlockable bound entangled state. We find that the bound
entangled state is as useful as the GHZ state, even do better than the GHZ
state in the context of communication security.Comment: 4 pages,1 figur
Lung emphysema and lung cancer: what do we know about it?
Emphysema and lung cancer (LC) are two diseases which share common risk factors, e.g., smoking. In recent years, many studies have sought to analyse this association. By way of illustration, we conducted a review of the scientific literature of the studies published to date, whose main designated aim was to demonstrate the relationship between emphysema and LC, and this association's influence on the histology, prognosis and molecular mechanisms responsible. We included over 40 studies (ranging from case-control and cohort studies to systematic reviews and meta-analyses), which highlight the association between emphysema and LC, independently of smoking habit. These studies also report a possible influence on histology, with adenocarcinoma being the most frequent lineage, and an association with poor prognosis, which affects both survival and post-operative complications. Oxidative stress, which generates chronic inflammatory status as well as the presence of certain polymorphisms in various genes (CYP1A1, TERT, CLPTM1L, ERK), gives rise-in the case of patients with emphysema-to alteration of cellular repair mechanisms, which in turn favours the proliferation of neoplastic epithelial cells responsible for the origin of LC
New classes of n-copy undistillable quantum states with negative partial transposition
The discovery of entangled quantum states from which one cannot distill pure
entanglement constitutes a fundamental recent advance in the field of quantum
information. Such bipartite bound-entangled (BE) quantum states \emph{could}
fall into two distinct categories: (1) Inseparable states with positive partial
transposition (PPT), and (2) States with negative partial transposition (NPT).
While the existence of PPT BE states has been confirmed, \emph{only one} class
of \emph{conjectured} NPT BE states has been discovered so far. We provide
explicit constructions of a variety of multi-copy undistillable NPT states, and
conjecture that they constitute families of NPT BE states. For example, we show
that for every pure state of Schmidt rank greater than or equal to three, one
can construct n-copy undistillable NPT states, for any . The abundance
of such conjectured NPT BE states, we believe, considerably strengthens the
notion that being NPT is only a necessary condition for a state to be
distillable.Comment: Latex, 10 page
Storm impacts on phytoplankton community dynamics in lakes
In many regions across the globe, extreme weather events such as storms have increased in frequency, intensity, and duration due to climate change. Ecological theory predicts that such extreme events should have large impacts on ecosystem structure and function. High winds and precipitation associated with storms can affect lakes via shortâterm runoff events from watersheds and physical mixing of the water column. In addition, lakes connected to rivers and streams will also experience flushing due to high flow rates. Although we have a wellâdeveloped understanding of how wind and precipitation events can alter lake physical processes and some aspects of biogeochemical cycling, our mechanistic understanding of the emergent responses of phytoplankton communities is poor. Here we provide a comprehensive synthesis that identifies how storms interact with lake and watershed attributes and their antecedent conditions to generate changes in lake physical and chemical environments. Such changes can restructure phytoplankton communities and their dynamics, as well as result in altered ecological function (e.g., carbon, nutrient and energy cycling) in the shortâ and longâterm. We summarize the current understanding of stormâinduced phytoplankton dynamics, identify knowledge gaps with a systematic review of the literature, and suggest future research directions across a gradient of lake types and environmental conditions
Impact of extreme weather events frequency and intensity in shaping phytoplankton communities
Lake habitats and communities can often be correlated with general morphometric and geographic
characteristics such as depth, latitude, altitude, or watershed area. Further, communities are typically
correlated with average environmental conditions such as seasonal temperature and nutrient levels. The
frequency and intensity of extreme weather events (rain and wind) are typically not encompassed by average
environmental descriptors, yet, can modify the physical habitats of lakes, significantly influencing
phytoplankton growth and survival. We tested the hypothesis that lakes with a higher frequency and intensity
of extreme weather events have a functionally different phytoplankton assemblage from lakes with a lower
frequency of extreme weather events. We compiled long-term (mean = 20±13 years, range 0.6-44 years)
phytoplankton datasets for 22 lakes across a wide gradient of altitude, latitude, depth, and trophic state. We
classified the phytoplankton genera into morpho-functional groups and C-S-R strategists, and compared
among lake phytoplankton assemblagesâ characteristics across the gradient of wind and rain conditions
experienced by the lakes. We discuss how the frequency of extreme weather events can affect phytoplankton
functional groups, the dominance of differing life history strategies and ultimately community structure. The
frequency and intensity of extreme events is expected to increase with climate change, with the potential to
drive shifts in phytoplankton composition
A global dataset on weather, lake physics, and phytoplankton dynamics
We compiled data from over 30 lakes across the globe to address how storms influence thermal structure
and phytoplankton community dynamics mediated by lake conditions and functional traits. In addition to
(generally) fortnightly phytoplankton samples (mean ± SD temporal coverage across all lakes = 20 ± 13 years),
the dataset includes limnological variables from standard long-term monitoring programs (24 ± 15 years
coverage), daily weather observations (16 ± 10 years coverage) and, when available, high-frequency lake
water temperature and water chemistry profiles (12 ± 7 years coverage). All data have been standardized to
similar formats and include complete metadata. We used the dataset to develop an R-package
(âalgaeClassifyâ), which assigns phytoplankton genus/species information to multiple functional trait groups,
and here we provide a summary of ongoing research using the dataset to investigate: 1) the influence of storm
events on seasonal phytoplankton succession, 2) the impact of storms on lake thermal structure, and 3)
whether lake phytoplankton communities are shaped by long-term patterns in disturbance frequency and
intensity. We give an overview on how to access these data, and we further highlight the opportunities the
dataset provides for asking both basic and applied questions in limnology, ecology, climate change, and lake
management
Quantum Cryptography
Quantum cryptography could well be the first application of quantum mechanics
at the individual quanta level. The very fast progress in both theory and
experiments over the recent years are reviewed, with emphasis on open questions
and technological issues.Comment: 55 pages, 32 figures; to appear in Reviews of Modern Physic
Separability and entanglement in 2x3xN composite quantum systems
The separability and entanglement of quantum mixed states in \Cb^2 \otimes
\Cb^3 \otimes \Cb^N composite quantum systems are investigated. It is shown
that all quantum states with positive partial transposes and rank
are separable.Comment: Latex, 15 page
Polymorphisms in the BER and NER pathways and their influence on survival and toxicity in never-smokers with lung cancer
Polymorphisms in DNA repair pathways may play a relevant role in lung cancer survival in never-smokers. Furthermore, they could be implicated in the response to chemotherapy and toxicity of platinum agents. The aim of this study was to evaluate the influence of various genetic polymorphisms in the BER and NER DNA repair pathways on survival and toxicity in never-smoker LC patients. The study included never-smokers LC cases diagnosed from 2011 through 2019, belonging to the Lung Cancer Research In Never Smokers study. A total of 356 never-smokers cases participated (79% women; 83% adenocarcinoma and 65% stage IV). Survival at 3 and 5 years from diagnosis was not associated with genetic polymorphisms, except in the subgroup of patients who received radiotherapy or chemo-radiotherapy, and presented with ERCC1 rs3212986 polymorphism. There was greater toxicity in those presenting OGG1 rs1052133 (CG) and ERCC1 rs11615 polymorphisms among patients treated with radiotherapy or chemo-radiotherapy, respectively. In general, polymorphisms in the BER and NER pathways do not seem to play a relevant role in survival and response to treatment among never-smoker LC patients
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