A shallow-water model with horizontally nonuniform density is used to study the dynamics of jet flows that arise under the influence of buoyancy and the Coriolis force. Within this approach, the jet ...is described by a self-similar compactly-localized solution and interpreted as a band of shear flow having a temperature contrast with the ambient fluid. In addition to stationary states, the dynamics of such jets admit cyclonic rotation with a constant angular velocity and transverse nonlinear pulsations. The phase portrait corresponding to this model shows that regimes with pulsating jets develop along closed trajectories bounded by the separatrix loop. The theory predicts that the period for warm jet pulsations is longer than the inertial oscillation period caused by the Earth’s rotation, while for cold jet pulsations, it is shorter. Thus, only warm jets can have a noticeable effect on the atmospheric dynamics in the synoptic range. In particular, they may well be responsible for additional spectral peaks that appear in this range of wind speed fluctuations.
•The effect of buoyancy and the Coriolis on the dynamics of horizontal jets is studied.•The description for pulsating straight-line jets is derived from the TRSW model.•A criterion of jet pulsations in Earth conditions is formulated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
An increasing number of the population all around the world suffer from age-associated neurodegenerative diseases including Parkinson’s disease (PD). This disorder presents different signs of ...genetic, epigenetic and environmental origin, and molecular, cellular and intracellular dysfunction. At the molecular level, α-synuclein (αSyn) was identified as the principal molecule constituting the Lewy bodies (LB). The gut microbiota participates in the pathogenesis of PD and may contribute to the loss of dopaminergic neurons through mitochondrial dysfunction. The most important pathogenetic link is an imbalance of Ca2+ ions, which is associated with redox imbalance in the cells and increased generation of reactive oxygen species (ROS). In this review, genetic, epigenetic and environmental factors that cause these disorders and their cause-and-effect relationships are considered. As a constituent of environmental factors, the example of organophosphates (OPs) is also reviewed. The role of endothelial damage in the pathogenesis of PD is discussed, and a ‘triple hit hypothesis’ is proposed as a modification of Braak’s dual hit one. In the absence of effective therapies for neurodegenerative diseases, more and more evidence is emerging about the positive impact of nutritional structure and healthy lifestyle on the state of blood vessels and the risk of developing these diseases.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Energetic and angular distributions of the products of nuclear fusion reactions involving two colliding nuclei and two resulting particles are important in neutron spectrometry, as well as in studies ...of the behaviour of fast electrically charged particles in plasma, such as protons, tritons, helions and α-particles in the megaelectronvolt range. This also applies to primordial nucleosynthesis and astrophysics since the reaction rates in cosmic plasma can also be affected by suprathermal particles. The possibility of a reduction of the S-algorithm to a triple integral is demonstrated for the case of isotropic velocity distributions of projectile and target particles.
Morphologically, polytene chromosomes of Drosophila melanogaster consist of compact "black" bands alternating with less compact "grey" bands and interbands. We developed a comprehensive approach that ...combines cytological mapping data of FlyBase-annotated genes and novel tools for predicting cytogenetic features of chromosomes on the basis of their protein composition and determined the genomic coordinates for all black bands of polytene chromosome 2R. By a PCNA immunostaining assay, we obtained the replication timetable for all the bands mapped. The results allowed us to compare replication timing between polytene chromosomes in salivary glands and chromosomes from cultured diploid cell lines and to observe a substantial similarity in the global replication patterns at the band resolution level. In both kinds of chromosomes, the intervals between black bands correspond to early replication initiation zones. Black bands are depleted of replication initiation events and are characterized by a gradient of replication timing; therefore, the time of replication completion correlates with the band length. The bands are characterized by low gene density, contain predominantly tissue-specific genes, and are represented by silent chromatin types in various tissues. The borders of black bands correspond well to the borders of topological domains as well as to the borders of the zones showing H3K27me3, SUUR, and LAMIN enrichment. In conclusion, the characteristic pattern of polytene chromosomes reflects partitioning of the Drosophila genome into two global types of domains with contrasting properties. This partitioning is conserved in different tissues and determines replication timing in Drosophila.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A double algebra is a linear space V equipped with linear map V⊗V→V⊗V. Additional conditions on this map lead to the notions of Lie and associative double algebras. We prove that simple ...finite-dimensional Lie double algebras do not exist over an arbitrary field, and all simple finite-dimensional associative double algebras over an algebraically closed field are trivial. Over an arbitrary field, every simple finite-dimensional associative double algebra is commutative. A double algebra structure on a finite-dimensional space V is naturally described by a linear operator R on the algebra EndV of linear transformations of V. Double Lie algebras correspond in this sense to skew-symmetric Rota–Baxter operators, double associative algebra structures – to (left) averaging operators.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
BACKGROUND—Enhanced proliferation, resistance to apoptosis, and metabolic shift to glycolysis of pulmonary arterial vascular smooth muscle cells (PAVSMCs) are key pathophysiological components of ...pulmonary vascular remodeling in idiopathic pulmonary arterial hypertension (PAH). The role of the distinct mammalian target of rapamycin (mTOR) complexes mTORC1 (mTOR-Raptor) and mTORC2 (mTOR-Rictor) in PAVSMC proliferation and survival in PAH and their therapeutic relevance are unknown.
METHODS AND RESULTS—Immunohistochemical and immunoblot analyses revealed that mTORC1 and mTORC2 pathways are markedly upregulated in small remodeled pulmonary arteries and isolated distal PAVSMCs from subjects with idiopathic PAH that have increased ATP levels, proliferation, and survival that depend on glycolytic metabolism. Small interfering RNA– and pharmacology-based analysis showed that although both mTORC1 and mTORC2 contribute to proliferation, only mTORC2 is required for ATP generation and survival of idiopathic PAH PAVSMCs. mTORC2 downregulated the energy sensor AMP-activated protein kinase, which led to activation of mTORC1-S6 and increased proliferation, as well as a deficiency of the proapoptotic protein Bim and idiopathic PAH PAVSMC survival. NADPH oxidase 4 (Nox4) protein levels were increased in idiopathic PAH PAVSMCs, which was necessary for mTORC2 activation, proliferation, and survival. Nox4 levels and mTORC2 signaling were significantly upregulated in small pulmonary arteries from hypoxia-exposed rats at days 2 to 28 of hypoxia. Treatment with the mTOR kinase inhibitor PP242 at days 15 to 28 suppressed mTORC2 but not Nox4, induced smooth muscle–specific apoptosis in small pulmonary arteries, and reversed hypoxia-induced pulmonary vascular remodeling in rats.
CONCLUSIONS—These data provide a novel mechanistic link of Nox4-dependent activation of mTORC2 via the energy sensor AMP-activated protein kinase to increased proliferation and survival of PAVSMCs in PAH, which suggests a new potential pathway for therapeutic interventions.
Type 1 diabetes mellitus is associated with decreased insulin-like growth factor-1 (IGF-1) levels, enhanced values of growth hormone (GH) and IGF-binding protein 1 (IGFBP-1). Since the liver is the ...major source of IGF and IGFBP production, we have therefore examined whether levels of IGFs (IGF-1 and IGF-11) and IGFBPs (IGFBP-1 and IGFBP-3) differ when insulin is infused into the portal or peripheral vascular system. IGF, IGFBP, and GH levels were determined within 1-3 weeks of diagnosis in 36 patients (ranging in age from 18 to 22 years) with Type 1 diabetes mellitus. IGF-1 levels were low before insulin therapy administration (0.49 +/- 0.05 vs. 1.11 +/- 0.04 U/ml in controls, P < 0.01). With insulin treatment, IGF-1 levels rose to the normal range and IGF-1 normalisation depended on diabetes control and the route of insulin infusion. Diabetic patients with conventional insulin therapy (CIT; n = 12) had low IGF-1 (0.57 +/- 0.07 U/ml) compared with patients with continuous subcutaneous insulin infusion (CSII; n = 12; 0.75 +/- 0.08 U/ml; P < 0.05) and intraportal insulin infusion (IPII; n = 12; 1.07 +/- 10.05 U/ml; P < 0.05). Significant correlations were found between IGF-1 and parameters of glycemic control: HbA1c (r = -0.64; P < 0.01) and glycemia (r = -0.56; P < 0.05). The pattern of changes in IGF-11 levels was not significantly different from that of controls and was not altered by insulin therapy (0.98 +/- 0.08 and 1.01 +/- 0.04 U/ml in controls). Measured fasting 08:00 h IGFBP-1 levels were elevated 3-fold and IGFGP-3 levels were 2-fold lower in diabetic patients than in controls. Elevated IGFBP-1 levels were significantly correlated with metabolic control (glycemia, r = 0.64, P < 0.01; HbA1c, r = 0.71, P < 0.01). The mean elevated GH level before insulin administration (13.4 +/- 0.9 mg/l) was decreased by intensified insulin therapy (CSII, 8.8 +/- 0.6, P < 0.05; IPII, 5.6 +/- 0.9 mg/l, P < 0.001). There was a negative correlation between GH and IGF-1 (r = -0.72, P < 0.01). These results show the role of glycemic control and the route of insulin administration in the normalisation of IGF-1, IGFBP-1 and GH up to non-diabetic controls in patients with recent-onset Type 1 diabetes mellitus.
Cross-beam energy transfer (CBET) results from two-beam energy exchange via seeded stimulated Brillouin scattering, which detrimentally reduces ablation pressure and implosion velocity in ...direct-drive inertial confinement fusion. Mitigating CBET is demonstrated for the first time in inertial-confinement implosions at the National Ignition Facility by detuning the laser-source wavelengths (±2.3 Å UV) of the interacting beams. We show that, in polar direct-drive, wavelength detuning increases the equatorial region velocity experimentally by 16% and alters the in-flight shell morphology. These experimental observations are consistent with design predictions of radiation-hydrodynamic simulations that indicate a 10% increase in the average ablation pressure.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
A new class of ignition designs is proposed for inertial confinement fusion experiments. These designs are based on the hot-spot ignition approach, but instead of a conventional target that is ...comprised of a spherical shell with a thin frozen deuterium-tritium (DT) layer, a liquid DT sphere inside a wetted-foam shell is used, and the lower-density central region and higher-density shell are created dynamically by appropriately shaping the laser pulse. These offer several advantages, including simplicity in target production (suitable for mass production for inertial fusion energy), absence of the fill tube (leading to a more-symmetric implosion), and lower sensitivity to both laser imprint and physics uncertainty in shock interaction with the ice-vapor interface. The design evolution starts by launching an ∼ 1 -Mbar shock into a DT sphere. After bouncing from the center, the reflected shock reaches the outer surface of the sphere and the shocked material starts to expand outward. Supporting ablation pressure ultimately stops such expansion and subsequently launches a shock toward the target center, compressing the ablator and fuel, and forming a shell. The shell is then accelerated and fuel is compressed by appropriately shaping the drive laser pulse, forming a hot spot using the conventional or shock ignition approaches. This Letter demonstrates the feasibility of the new concept using hydrodynamic simulations and discusses the advantages and disadvantages of the concept compared with more-traditional inertial confinement fusion designs.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
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