60 research outputs found
Photon echo in ring cavity: pulse area approach
Pulse area approach has been established as a versatile analytical tool for
studying the resonant interaction between the light and the resonant atomic
ensemble. In recent years photon and spin echoes in cavity assisted schemes
become increasingly interesting. In this article we develop the photon echo
pulse area approach to describe primary and multi-pulse echo generation in the
atomic ensemble placed in the ring cavity. We show that the pulse area approach
predicts relative echo magnitudes and whether the system is operating in a
single- or a multi-pulse generation regime. We also analyze the conditions
needed for the realization of these generation regimes. This work develops the
pulse area theorem approach for analytical study of photon/spin echoes in
optical and microwave cavities and echo based protocols of quantum memory.Comment: 8 pages, 4 figure
State-of-the-art trends in the treatment of immune-mediated inflammatory kidney diseases: Translation of the fundamental science into clinical practice. A review
Immune-mediated kidney diseases like glomerulonephritis and tubulointerstitial nephritis are not the most common cause of chronic kidney disease in the population, however the difficulties in their management, as well as a more rapid deterioration of kidney function, compared to diabetes mellitus and hypertension, justify the importance of this problem for internal medicine. Due to the fundamental discoveries in pathology and to the introduction of various methods of laboratory and instrumental investigation in the second half of the XX century substantial progress was made in the diagnostic approaches and treatment of these conditions. State-of-the-art diagnostic approach requires complex evaluation of the clinical, laboratory and morphological data to identify the nosological form of the disease. The accumulation of knowledge in the field of diseases’ pathogenesis led to the revision of the current classification of glomerulonephritis that should be based on the immunopathogenesis of these conditions. The following phenotypes were suggested: autoimmunity-related, autoinflammation-related, alloimmunity-related, infections-related, and monoclonal gammopathy-related. The assessment of disease activity and chronicity in the kidney tissue should be mandatory. Personalized selection of the optimal treatment modality on the basis of the diagnosis, severity, and individual features of the patient is currently possible. The leading trends include rational prescription of glucocorticoids (steroid-sparing regimens) and cytotoxic agents, e.g. cyclophosphamide, as well as the introduction of multitarget regimens that include biologic agents or small molecules selectively suppressing B-cells or various complement pathways. Another mandatory component of treatment on par with immune suppression is nephroprotective therapy, which currently comprises not only traditional renin-angiotensin-aldosterone antagonists, but also endothelin receptor antagonists and sodium-glucose cotransporter-2 inhibitors. Current guidelines emphasize the importance of the non-pharmacological interventions for the implementation of the nephroprotective strategy. Rational combination of the aforementioned approaches allows for the optimization of the management of patients with immune-mediated kidney diseases, although it requires high competencies and strict adherence to the principles of the evidence-based medicine from the healthcare providers
Gout: from Hippocrates till the modern time
Gout (podagra) is one of the most ancient articular diseases. Its accurate mechanisms and causes were delineated only during the last century. Major historical investigatory steps are described in relation to causality and pathogenesis of the disease from Hippocrates ages till the modern time. The newest genetic and epidemiologic aspects of the disease are presented in this article
Quantum informatics with plasmonic metamaterials
Surface polaritons at a meta-material interface are proposed as qubits. The
SP fields are shown to have low losses, subwavelength confinement and can
demonstrate very small modal volume. These important properties are used to
demonstatre interesting applications in quantum information, i.e., coherent
control of weak fields and large Kerr nonlinearity at the low photon level
Bright ultra-broadband fiber-based biphoton source
In this Letter, we report a first experimental realization of bright
ultra-broadband (180 THz) fiber-based biphoton source with widely spectrally
separated signal and idler photons. Such a two-photon source is realized due to
the joint use of broadband phase-matching of interacting light waves and high
optical nonlinearity of a silica-core photonic crystal fiber. The high
performance of the developed fiber source identifies it as an important and
useful tool for a wide range of optical quantum applications
Effects of pot fishing on the physical condition of snow crab (Chionoecetes opilio) and southern Tanner crab (Chionoecetes bairdi)
The effects of commercial fishing with crab pots on the physical condition of the snow crab (Chionoecetes opilio) and southern Tanner crab (C. bairdi) were investigated in the Bering Sea and in Russian waters of the Sea of Okhotsk. In crabs that were subjected to pot hauling, the presence of gas embolism and the deformation of gill lamellae were found in histopathological investigations. Crab vitality, which was characterized subjectively through observation of behavioral responses, depended on not only the number of pot hauls but also the time between hauls. Immediately after repeated pot hauls at short time intervals (≤3 days), we observed a rapid decline in vitality of crabs. When hauling intervals were increased to >3 days, the condition of crabs did not significantly change. After repeated pot hauls, concentration of the respiratory pigment hemocyanin ([Hc]) was often lower in the hemolymph of crabs than in the hemolymph of freshly caught animals. Our research
indicated that changes in [Hc] in crabs after repeated pot hauls were caused by the effects of decompression and not by starvation of crabs in pots or exposure of crabs to air. We suggest that the decrease in [Hc] in hemolymph of snow and southern Tanner crabs was a response to the adverse effects of decompression and air-bubble disease. The decrease in [Hc] in affected crabs may be a result of mechanisms that regulate internal pressure in damaged gills to optimize respiratory circulation
Coherent control of low loss surface polaritons
We propose fast all-optical control of surface polaritons (SPs) by placing an
electromagnetically induced transparency (EIT) medium at an interface between
two materials. EIT provides longitudinal compression and a slow group velocity
while matching properties of the two materials at the interface provides strong
transverse confinement. In particular we show that an EIT medium near the
interface between a dielectric and a negative-index metamaterial can establish
tight longitudinal and transverse confinement plus extreme slowing of SPs, in
both transverse electric and transverse magnetic polarizations, while
simultaneously avoiding losses.Comment: 4 pages, 5 figure
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