Особливості планування і реалізації проектів ресторанного бізнесу

Ресторанний бізнес є однією із найбільш значущих складових індустрії гостинності. Водночас, ресторанний бізнес, з одного боку, є одним із засобів високоліквідного використання капіталу, а з іншого − середовищем із високим ступенем конкурентності. У всьому світі він є одним із найбільш розповсюджених видів малого бізнесу, тому заклади та підприємства ведуть між собою постійну боротьбу за сегментацію ринку, за пошук нових та за утримання постійних споживачів їхньої продукції та послуг. Всі заклади та підприємства повинні мати високий рівень конкурентоспроможності та мати свою унікальність

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Dispersions and solutions of single walled carbon nanotubes

THESIS 8420Large scale exfoliation of single walled carbon nanotubes (SWNTs) has been shown in various media. Debundling of SWNTS has been demonstrated by dilution of nanotube dispersions. On making the initial dispersions, large aggregates (~100s of microns) are removed by a mild centrifugation step resulting in an isotropic phase containing bundles of nanotubes. The root mean square bundle diameter, of bundles in this isotropic phase, has been shown to be concentration dependent. Such debundling has been demonstrated in the solvents N-methyl-2-pyrrolidone (NMP) and for the narcotic drug y- Butyrolactone, sometimes referred to as \u27liquid ecstasy\u27. After centrifugation, the dispersions are stable against sedimentation and further aggregation for a period of weeks at least. Atomic-force-microscopy studies on deposited films reveal that the bundle diameter distribution decreases dramatically as concentration is decreased. Detailed data analysis suggests the presence of an equilibrium bundle number density and that the dispersions self-arrange themselves to always remain close to the dilute/semi-dilute boundary. A population of individual nanotubes is always observed which increases with decreasing concentration until almost seventy percent of all dispersed objects are individual nanotubes at a concentration of 0.004 mg/ml in the NMP dispersions and for y- Butyrolactone forty percent of all dispersed objects are individual nanotubes at a concentration of 6x10\u27-4 mg/ml. The presence of individual nanotubes in NMP dispersion was confirmed by photoluminescence spectroscopy. Concentration dependence of the photoluminescence intensity confirms that the AFM measurements reflect the diameter distributions in-situ. In addition, Raman spectroscopy confirms the presence of large quantities of individual nanotubes in the deposited films

Differentiating Defect and Basal Plane Contributions to the Surface Energy of Graphite Using Inverse Gas Chromatography

Historically, reported values for the surface energy of graphite have covered a very wide range. Here, we use finite-dilution inverse gas chromatography (FD-IGC) to show that the dispersive component of the surface energy of graphite has contributions from edge and basal plane defects as well as from the hexagonal carbon lattice. The surface energy associated with the defect-free hexagonal lattice is measured at high probe-coverage to be 63 ± 7 mJ/m², independent of graphite type. However, the surface energy measured at low probe coverage varied from 125 to 175 mJ/m² depending on the graphite type. Simulation of the FD-IGC output for different binding site distributions allows us to associate this low-coverage surface energy with the binding of probe molecules to high energy defect sites. Importantly, we find the rate of decay of surface energy with probe coverage to carry information about the defect density. By analyzing the dependence of these properties on flake size, it is possible to separate out the contributions of edge and basal plane defects, estimating the basal plane defect content to be ∼10¹⁵ m^–2 for all graphite samples. Comparison with simulation gives some insights into the basal plane and defect binding energy distributions

Solvent Exfoliation of Transition Metal Dichalcogenides: Dispersibility of Exfoliated Nanosheets Varies Only Weakly between Compounds

We have studied the dispersion and exfoliation of four inorganic layered compounds, WS₂, MoS₂, MoSe₂, and MoTe₂, in a range of organic solvents. The aim was to explore the relationship between the chemical structure of the exfoliated nanosheets and their dispersibility. Sonication of the layered compounds in solvents generally gave few-layer nanosheets with lateral dimensions of a few hundred nanometers. However, the dispersed concentration varied greatly from solvent to solvent. For all four materials, the concentration peaked for solvents with surface energy close to 70 mJ/m², implying that all four have surface energy close to this value. Inverse gas chromatography measurements showed MoS₂ and MoSe₂ to have surface energies of ∼75 mJ/m², in good agreement with dispersibility measurements. However, this method suggested MoTe₂ to have a considerably larger surface energy (∼120 mJ/m²). While surface-energy-based solubility parameters are perhaps more intuitive for two-dimensional materials, Hansen solubility parameters are probably more useful. Our analysis shows the dispersed concentration of all four layered materials to show well-defined peaks when plotted as a function of Hansen’s dispersive, polar, and H-bonding solubility parameters. This suggests that we can associate Hansen solubility parameters of δ_D ∼ 18 MPa^1/2, δ_P ∼ 8.5 MPa^1/2, and δ_H ∼ 7 MPa^1/2 with all four types of layered material. Knowledge of these properties allows the estimation of the Flory–Huggins parameter, χ, for each combination of nanosheet and solvent. We found that the dispersed concentration of each material falls exponentially with χ as predicted by solution thermodynamics. This work shows that solution thermodynamics and specifically solubility parameter analysis can be used as a framework to understand the dispersion of two-dimensional materials. Finally, we note that in good solvents, such as cyclohexylpyrrolidone, the dispersions are temporally stable with >90% of material remaining dispersed after 100 h

Selenium-Enhanced Electron Microscopic Imaging of Different Aggregate Forms of a Segment of the Amyloid β Peptide in Cells

The aggregation of misfolded proteins is a common feature underlying a wide range of age-related degenerative disorders, including Alzheimer’s and Parkinson’s diseases. A key aspect of understanding the molecular origins of these conditions is to define the manner in which specific types of protein aggregates influence disease pathogenesis through their interactions with cells. We demonstrate how selenium-enhanced electron microscopy (SE-EM), combined with tomographic reconstruction methods, can be used to image, here at a resolution of 5–10 nm, the interaction with human macrophage cells of amyloid aggregates formed from Aβ_25–36, a fragment of the Aβ peptide whose self-assembly is associated with Alzheimer’s disease. We find that prefibrillar aggregates and mature fibrils are distributed into distinct subcellular compartments and undergo varying degrees of morphological change over time, observations that shed new light on the origins of their differential toxicity and the mechanisms of their clearance. In addition, the results show that SE-EM provides a powerful and potentially widely applicable means to define the nature and location of protein assemblies <i>in situ</i> and to provide detailed and specific information about their partitioning and processing