Search results for "vacuum"
showing 10 items of 352 documents
Kümmell's Disease: Clarifying the Mechanisms and Patients' Inclusion Criteria.
2014
The three major causes of vertebral body collapse include infection, malignant neoplasia, and trauma and it may be difficult to distinguish between them, particularly in the presence of severe osteoporosis. In 1891, however, Dr Hermann Kümmell, further added another possibility of vertebral body crush; the delayed posttraumatic collapse. As originally described, this rare clinical entity includes patients, who after a trivial trauma and an asymptomatic clinical course they develop a progressive vertebral body collapse and a painful kyphosis. Although more than a century has passed from its initial description, only few cases have been reported in the literature, whereas the main pathologic …
Vacuum inversion and securing of distal colonic pseudodiverticula with novel spiked O-rings
2015
Background Diverticular disease is increasingly prevalent in Western societies and is associated with significant morbidity. Objective Two-stage endoscopic device development for inversion and secured ligation of colonic diverticula; first, human cadaver studies were performed to measure forces required for diverticular inversion; second, a novel set of devices (elastic spiked O-ring with delivery system) was tested in animals. Design Prospective, observational study of human cadavers and prospective, interventional study of a porcine model. Setting University hospital pathology laboratory and animal facility. Intervention Full-thickness inversion of the colonic wall with a pipelike deliver…
Chemical-Based Methodologies to Extend the Shelf Life of Fresh Fish—A Review
2021
Due to its characteristics, fresh fish is a highly perishable food with a very short shelf-life under refrigeration. Several methods have been introduced to slow down its deterioration, such as by means of oxygen depletion of the food package (vacuum packaging), or by changing the natural atmosphere that is in contact with the fresh fish (modified atmosphere packaging), or by the use of chemicals generally recognized as safe: such compounds can be directly applied (by dipping or spraying) or incorporated into packaging materials and slowly migrate to the product, exerting a hurdle effect against microbial development and lipid oxidation (active packaging). This review aims to cover the most…
On-Surface Reactions
2015
On-surface synthesis constitutes a rapidly growing field of research due to its promising application for creating stable molecular structures on surfaces. While self-assembled structures rely on reversible interactions, on-surface synthesis provides the potential for creating long-term stable structures with well-controlled properties, for example superior electron transport for future molecular electronic devices. On-surface synthesis holds the promise for preparing insoluble compounds that cannot be produced in solution. Another highly exciting aspect of on-surface synthesis is the chance to discover new reaction pathways due to the two-dimensional confinement of the reaction educts. In …
Increasing the Astrophysical Reach of the Advanced Virgo Detector via the Application of Squeezed Vacuum States of Light
2019
Current interferometric gravitational-wave detectors are limited by quantum noise over a wide range of their measurement bandwidth. One method to overcome the quantum limit is the injection of squeezed vacuum states of light into the interferometer's dark port. Here, we report on the successful application of this quantum technology to improve the shot noise limited sensitivity of the Advanced Virgo gravitational-wave detector. A sensitivity enhancement of up to 3.2±0.1 dB beyond the shot noise limit is achieved. This nonclassical improvement corresponds to a 5%-8% increase of the binary neutron star horizon. The squeezing injection was fully automated and over the first 5 months of the thi…
Non-adiabatic vacuum induced berry phase
2016
We investigate quantum effects in geometric phases arising when a two-level system is interacting with a quantized electromagnetic field.
Study of scintillation light collection, production and propagation in a 4 tonne dual-phase LArTPC
2020
The $3 \times 1 \times 1$ m$^3$ demonstrator is a dual phase liquid argon time projection chamber that has recorded cosmic rays events in 2017 at CERN. The light signal in these detectors is crucial to provide precise timing capabilities. The performances of the photon detection system, composed of five PMTs, are discussed. The collected scintillation and electroluminescence light created by passing particles has been studied in various detector conditions. In particular, the scintillation light production and propagation processes have been analyzed and compared to simulations, improving the understanding of some liquid argon properties.
VUV emission spectroscopy combined with H- density measurements in the ion source Prometheus I
2016
“Prometheus I” is a volume H− negative ion source, driven by a network of dipolar electron cyclotron resonance (ECR; 2.45 GHz) modules. The vacuum-ultraviolet (VUV) emission spectrum of low-temperature hydrogen plasmas may be related to molecular and atomic processes involved directly or indirectly in the production of negative ions. In this work, VUV spectroscopy has been performed in the above source, Prometheus I, both in the ECR zones and the bulk (far from ECR zones and surfaces) plasma. The acquired VUV spectra are correlated with the negative ion densities, as measured by means of laser photodetachment, and the possible mechanisms of negative ion production are considered. The well-e…
Negatīvā spiediena terapijas ietekme uz organisma homeostāzi
2016
Literatūras norāda uz to, ka negatīvā spiediena brūču terapija sekmē ātrāku audu defekta dzīšanu. Šīs terapijas iespējamais blakusefekts var būt organisma proteīnu zudums. Vidējais kopējā proteīna līmenis eksudātā ir 57 g/L, bet albumīna līmenis ir 21 g/L. Terapija specifisks proteīna zudums var tikt aprēķināts reizinot seruma albumīnu ar 0.3. Literatūras datiem atbilstošu olbaltumvielu uzņemšanu, kas sastāda 1.5g/kg/dienā ir attiecīgi jāreizina ar 1.3, rezultātā iegūstot 2.0 g/kg/dienā. Oriģinālās savākšanas sistēmas tika pielietotas veiksmīgi, un laboratoriskie protokoli attiecībā pret eksudātiem tika paplašināti. Šis pētījums ir ieguldījums sarežģītā zinātnē par brūču dzīšanu, prasībām p…
Effect of different packaging methods on the free amino acid profiles of the deep-water rose shrimp (Parapenaeus longirostris) during frozen storage
2022
The composition of free amino acids (FAAs) in seafood products contributes to characterizing their flavor, as well as freshness and quality during storage. Deep-water rose shrimps (Parapenaues longirostris, Lucas, 1846) (DWRS) are being increasingly harvested in the Mediterranean Sea, and the captured specimens are quickly frozen onboard fishing trawlers to preserve freshness and post-harvest quality. Here, we quantified the FAA profiles of DWRS packaged using five methods: (1) 100% N2; (2) vacuum; (3) 50% N2 + 50% CO2; (4) commercial anhydrous sodium sulfite; and (5) air (control). All samples were quickly frozen at −35°C and stored for 12 months at −18°C. Arginine (661 mg/100 g), proline …