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1.
Phys Rev Lett ; 131(10): 105101, 2023 Sep 08.
Article in English | MEDLINE | ID: mdl-37739360

ABSTRACT

In direct-drive inertial confinement fusion, the laser bandwidth reduces the laser imprinting seed of hydrodynamic instabilities. The impact of varying bandwidth on the performance of direct-drive DT-layered implosions was studied in targets with different hydrodynamic stability properties. The stability was controlled by changing the shell adiabat from (α_{F}≃5) (more stable) to (α_{F}≃3.5) (less stable). These experiments show that the performance of lower adiabat implosions improves considerably as the bandwidth is raised indicating that further bandwidth increases, beyond the current capabilities of OMEGA, would be greatly beneficial. These results suggest that the future generation of ultra-broadband lasers could enable achieving high convergence and possibly high gains in direct drive ICF.

2.
Phys Rev Lett ; 131(1): 015102, 2023 Jul 07.
Article in English | MEDLINE | ID: mdl-37478441

ABSTRACT

In the dynamic-shell (DS) concept [V. N. Goncharov et al., Novel Hot-Spot Ignition Designs for Inertial Confinement Fusion with Liquid-Deuterium-Tritium Spheres, Phys. Rev. Lett. 125, 065001 (2020).PRLTAO0031-900710.1103/PhysRevLett.125.065001] for laser-driven inertial confinement fusion the deuterium-tritium fuel is initially in the form of a homogeneous liquid inside a wetted-foam spherical shell. This fuel is ignited using a conventional implosion, which is preceded by a initial compression of the fuel followed by its expansion and dynamic formation of a high-density fuel shell with a low-density interior. This Letter reports on a scaled-down, proof-of-principle experiment on the OMEGA laser demonstrating, for the first time, the feasibility of DS formation. A shell is formed by convergent shocks launched by laser pulses at the edge of a plasma sphere, with the plasma itself formed as a result of laser-driven compression and relaxation of a surrogate plastic-foam ball target. Three x-ray diagnostics, namely, 1D spatially resolved self-emission streaked imaging, 2D self-emission framed imaging, and backlighting radiography, have shown good agreement with the predicted evolution of the DS and its stability to low Legendre mode perturbations introduced by laser irradiation and target asymmetries.

3.
Surg Endosc ; 37(3): 1629-1648, 2023 03.
Article in English | MEDLINE | ID: mdl-36781468

ABSTRACT

BACKGROUND: In recent years, the use of Indocyanine Green (ICG) fluorescence-guided surgery during open and laparoscopic procedures has exponentially expanded across various clinical settings. The European Association of Endoscopic Surgery (EAES) initiated a consensus development conference on this topic with the aim of creating evidence-based statements and recommendations for the surgical community. METHODS: An expert panel of surgeons has been selected and invited to participate to this project. Systematic reviews of the PubMed, Embase and Cochrane libraries were performed to identify evidence on potential benefits of ICG fluorescence-guided surgery on clinical practice and patient outcomes. Statements and recommendations were prepared and unanimously agreed by the panel; they were then submitted to all EAES members through a two-rounds online survey and results presented at the EAES annual congress, Barcelona, November 2021. RESULTS: A total of 18,273 abstracts were screened with 117 articles included. 22 statements and 16 recommendations were generated and approved. In some areas, such as the use of ICG fluorescence-guided surgery during laparoscopic cholecystectomy, the perfusion assessment in colorectal surgery and the search for the sentinel lymph nodes in gynaecological malignancies, the large number of evidences in literature has allowed us to strongly recommend the use of ICG for a better anatomical definition and a reduction in post-operative complications. CONCLUSIONS: Overall, from the systematic literature review performed by the experts panel and the survey extended to all EAES members, ICG fluorescence-guided surgery could be considered a safe and effective technology. Future robust clinical research is required to specifically validate multiple organ-specific applications and the potential benefits of this technique on clinical outcomes.


Subject(s)
Cholecystectomy, Laparoscopic , Laparoscopy , Humans , Indocyanine Green , Consensus , Fluorescence , Laparoscopy/methods
4.
Surg Endosc ; 34(7): 3270-3284, 2020 07.
Article in English | MEDLINE | ID: mdl-32274626

ABSTRACT

BACKGROUND: Indocyanine green fluorescence vision is an upcoming technology in surgery. It can be used in three ways: angiographic and biliary tree visualization and lymphatic spreading studies. The present paper shows the most outstanding results from an health technology assessment study design, conducted on fluorescence-guided compared with standard vision surgery. METHODS: A health technology assessment approach was implemented to investigate the economic, social, ethical, and organizational implications related to the adoption of the innovative fluorescence-guided view, with a focus on minimally invasive approach. With the support of a multidisciplinary team, qualitative and quantitative data were collected, by means of literature evidence, validated questionnaires and self-reported interviews, considering the dimensions resulting from the EUnetHTA Core Model. RESULTS: From a systematic search of literature, we retrieved the following studies: 6 on hepatic, 1 on pancreatic, 4 on biliary, 2 on bariatric, 4 on endocrine, 2 on thoracic, 11 on colorectal, 7 on urology, 11 on gynecology, 2 on gastric surgery. Fluorescence guide has shown advantages on the length of hospitalization particularly in colorectal surgery, with a reduction of the rate of leakages and re-do anastomoses, in spite of a slight increase in operating time, and is confirmed to be a safe, efficacious, and sustainable vision technology. Clinical applications are still presenting a low evidence in the literature. CONCLUSION: The present paper, under the patronage of Italian Society of Endoscopic Surgery, based on an HTA approach, sustains the use of fluorescence-guided vision in minimally invasive surgery, in the fields of general, gynecologic, urologic, and thoracic surgery, as an efficient and economically sustainable technology.


Subject(s)
Efficiency, Organizational , Endoscopy/methods , Fluorescence , Indocyanine Green , Surgery, Computer-Assisted/methods , Sustainable Development , Humans , Italy , Operative Time , Qualitative Research , Societies, Medical , Systematic Reviews as Topic , Technology Assessment, Biomedical
5.
Nature ; 565(7741): 581-586, 2019 01.
Article in English | MEDLINE | ID: mdl-30700868

ABSTRACT

Focusing laser light onto a very small target can produce the conditions for laboratory-scale nuclear fusion of hydrogen isotopes. The lack of accurate predictive models, which are essential for the design of high-performance laser-fusion experiments, is a major obstacle to achieving thermonuclear ignition. Here we report a statistical approach that was used to design and quantitatively predict the results of implosions of solid deuterium-tritium targets carried out with the 30-kilojoule OMEGA laser system, leading to tripling of the fusion yield to its highest value so far for direct-drive laser fusion. When scaled to the laser energies of the National Ignition Facility (1.9 megajoules), these targets are predicted to produce a fusion energy output of about 500 kilojoules-several times larger than the fusion yields currently achieved at that facility. This approach could guide the exploration of the vast parameter space of thermonuclear ignition conditions and enhance our understanding of laser-fusion physics.

6.
Br J Surg ; 105(13): 1835-1843, 2018 12.
Article in English | MEDLINE | ID: mdl-30006923

ABSTRACT

BACKGROUND: Laparoscopic lavage was proposed in the 1990s to treat purulent peritonitis in patients with perforated acute diverticulitis. Prospective randomized trials had mixed results. The aim of this study was to determine the success rate of laparoscopic lavage in sepsis control and to identify a group of patients that could potentially benefit from this treatment. METHODS: This retrospective multicentre international study included consecutive patients from 24 centres who underwent laparoscopic lavage from 2005 to 2015. RESULTS: A total of 404 patients were included, 231 of whom had Hinchey III acute diverticulitis. Sepsis control was achieved in 172 patients (74·5 per cent), and was associated with lower Mannheim Peritonitis Index score and ASA grade, no evidence of free perforation, absence of extensive adhesiolysis and previous episodes of diverticulitis. The operation was immediately converted to open surgery in 19 patients. Among 212 patients who underwent laparoscopic lavage, the morbidity rate was 33·0 per cent; the reoperation rate was 13·7 per cent and the 30-day mortality rate 1·9 per cent. Twenty-one patients required readmission for early complications, of whom 11 underwent further surgery and one died. Of the 172 patients discharged uneventfully after laparoscopic lavage, a recurrent episode of acute diverticulitis was registered in 46 (26·7 per cent), at a mean of 11 (range 2-108) months. Relapse was associated with younger age, female sex and previous episodes of acute diverticulitis. CONCLUSION: Laparoscopic lavage showed a high rate of successful sepsis control in selected patients with perforated Hinchey III acute diverticulitis affected by peritonitis, with low rates of operative mortality, reoperation and stoma formation.


Subject(s)
Diverticulitis, Colonic/surgery , Laparoscopy/methods , Peritoneal Lavage/methods , Peritonitis/surgery , Acute Disease , Colostomy/statistics & numerical data , Conversion to Open Surgery/statistics & numerical data , Diverticulitis, Colonic/complications , Female , Humans , Male , Middle Aged , Peritonitis/etiology , Reoperation/statistics & numerical data , Retrospective Studies , Sepsis/prevention & control
8.
Phys Rev Lett ; 117(2): 025001, 2016 Jul 08.
Article in English | MEDLINE | ID: mdl-27447511

ABSTRACT

A record fuel hot-spot pressure P_{hs}=56±7 Gbar was inferred from x-ray and nuclear diagnostics for direct-drive inertial confinement fusion cryogenic, layered deuterium-tritium implosions on the 60-beam, 30-kJ, 351-nm OMEGA Laser System. When hydrodynamically scaled to the energy of the National Ignition Facility, these implosions achieved a Lawson parameter ∼60% of the value required for ignition [A. Bose et al., Phys. Rev. E 93, 011201(R) (2016)], similar to indirect-drive implosions [R. Betti et al., Phys. Rev. Lett. 114, 255003 (2015)], and nearly half of the direct-drive ignition-threshold pressure. Relative to symmetric, one-dimensional simulations, the inferred hot-spot pressure is approximately 40% lower. Three-dimensional simulations suggest that low-mode distortion of the hot spot seeded by laser-drive nonuniformity and target-positioning error reduces target performance.

9.
Oral Implantol (Rome) ; 5(1): 3-10, 2012 Jan.
Article in English | MEDLINE | ID: mdl-23285400

ABSTRACT

It has been suggested that for success with immediate loaded dental implants it is necessary that, prior to their placement, bone quality and quantity as well as the biomechanical environment in which the implants are to function be evaluated.However, conventional techniques currently used for immediate implant placement lack sufficient precision and are usually accomplished by opening flap procedures. Nowadays computer-guided flapless surgery for implant placement using stereolithographic templates is gaining popularity among clinicians and patients. The advantages of this surgical protocol are its minimally invasive nature, accuracy of implant placement, predictability, less post-surgical disconfort and reduced time required for definitive rehabilitation. The introduction of digital planning programs has made it possible to place dental implants in preplanned positions and being immediately functionally loaded by using prefabricated prostheses. The surgical guide is used, infact, to develop a master model and fabricate the provisional bridge that will be secured to the implants immediately after their placement using the guided surgery template. In this way patients are able to achieve, in the same day of the surgery, a comfortable fixed rehabilitation needing only minor occlusal adjustments. Job S. et al during the three-month period, have demonstrated that the average reduction of crestal bone height around the implants placed with flapless surgery (0.06 mm) is not statistically significant, while the average reduction of crestal bone height around the implants placed using flap surgery (0.4 mm) is statistically significant, concluding that the use of stereolithographic appliances in accordance with flapless surgery makes immediate placement of the implants more predictable. However, the documentation of this technique in partial rehabilitations is limited. PURPOSE of this paper is to report the benefit of sophisticated pre-operative diagnostic implant planning and a flapless surgical approach with immediate loading in the rehabilitation of partial edentulies.

10.
Oral Implantol (Rome) ; 4(3-4): 23-33, 2011 Jul.
Article in English | MEDLINE | ID: mdl-23277870

ABSTRACT

The prevalence of the elderly population, as well as life expectancy, increased in the final decades of the 20th century, as described in the World Health Organization 2004 Annual Report. The edentulous condition therefore has a negative impact on the oral health-related quality of life. Patients wearing complete dentures for many years infact, and especially in the mandible, are often unsatisfied because of the instability of the prosthesis during speaking and eating. To date dental implant treatment is well documented as a predictable treatment for partial or complete edentulism. On the other hand the rehabilitation of atrophied edentulous arches with endosseous implants (> 10 mm) in the posterior regions is often associated with anatomic problems such as bone resorption, poor bone quality, mandibular canal, and the presence of maxillary sinuses. Different procedures have been proposed to overcome these anatomic limitations. The use of tilted implants parallel to the anterior wall of the maxillary sinus or the mental foramen/inferior alveolar nerve has been proposed as a conservative solution for the treatment of the atrophic edentulous maxilla. Aim of this study was to describe, through a detailed literature review, the clinical and biomechanical rationale for tilting implants and to evaluate the long-term prognosis of immediately loaded full fixed prostheses for the treatment of edentulous patients (#35) with extreme bone atrophy rehabilited with both axial (#70) and tilted (#70) implants from 2008 to 2010. The results of the present study would suggest that this new surgical technique may reduce patient morbidity and extend the indications for immediate loading full fixed rehabilitations. This improves the predictability of treatment goal, allows for a better risk management, and provides more individual information for the patient. These are the most important aspects of this technology, which may contribute to establish higher-quality standards in implantology.

11.
Oral Implantol (Rome) ; 3(2): 10-9, 2010 Apr.
Article in English | MEDLINE | ID: mdl-23285381

ABSTRACT

The severe atrophy of the jaws are a challenging therapeutic problem, since the increase in bone is necessary to allow the placement of a sufficient number of implants. Combining immediate functionalization with the concept of guided surgery they combine the advantages offered by the innovative surgical and prosthetic implant technique (All-on-Four(®)) with those of computer-assisted planning in cases of severe bone atrophy. The method used in this case report, combines these two concepts in a surgical and prosthetic protocol safe and effective for the immediate function of 4 implants to support a fixed prosthesis in completely edentulous subjects. The integration of technology with immediate function with the concept of computer-guided surgery for implant placement and rehabilitation of completely edentulous jaws is now a predictable treatment modality with implant survival comparable to the traditional protocols.

12.
Oral Implantol (Rome) ; 3(2): 20-8, 2010 Apr.
Article in English | MEDLINE | ID: mdl-23285382

ABSTRACT

The object of our work is the illustration of an alternative technique in the impress survey in fixed prosthesis. This method conceived from Doctor Casartelli, allowed us to utilize this technology in the day-to-day activity eliminating also the anaesthetic use, so give the possibility to operate patients with anticoagulant therapy.Moreover the mini-invasive techniques allow a lowering recessions, best tolerability from the patients, less pain and postoperative inflammation, "restitutio ad integrum" of tissue without morphological modifications.

13.
Oral Implantol (Rome) ; 2(1): 27-36, 2009 Jan.
Article in English | MEDLINE | ID: mdl-23285355

ABSTRACT

The "screw shaped" expansion-condenser are hand instruments that were introduced for the first time at the end of the 70' in order to improve bone density before the positioning of a dental implant. Thanks to these hand instruments it is possibile to compact the bone apically and along the walls of the implant bed (Fig. 3) improving a lot the bone density and the primary stability of the implant even in situations where the starting bone quality is low (es. D3-D4 as in the classification y Lekholm and Zarb 1985) or in cases of severe bone atrophy. Allowing a manageable raising of the shnaiderian membrane through trans-alveolar way, this technique avoids in many cases the necessity to have recourse to the realisation of bone vestibular "gates" when it comes to the techniques of the big sinus lift. The knoledge of the bone visco-elastic and hystologic properties together with the maximum respect of the surgical protocol allows us to obtein % of success superior than traditional surgical protocol in D3-D4 bone class.

14.
Oral Implantol (Rome) ; 2(4): 26-34, 2009 Oct.
Article in English | MEDLINE | ID: mdl-23285372

ABSTRACT

The osteonecrosis of the maxillares caused by bisphosphonates (OMB) either wrongly known or not reconised in earlier times became nowadays very important among the dentists and maxillo-facials surgeons because of the potential serious consequences that might bring in the oral cave of the patients, who are suffering already for their base condition. The goal of our work was to verify if a deep treatment and an attentive observation with a close follow-up can bring to the resolution of serious cases of ostenecrosis of the maxillares by bisphosphonantes. Although without a statistic value our case report put the basis for a chance to execute wider casistic studies.

15.
Oral Implantol (Rome) ; 1(3-4): 104-15, 2008 Oct.
Article in English | MEDLINE | ID: mdl-23285346

ABSTRACT

In the last 15 years the increasing aesthetic demand, push constantly industry and the clinical to entirely look for new solutions for the realization of all-ceramic crowns, with such characteristics to be used for both anterior and posterior restorations. The most greater contribution, in such sense derives from the finished progress in the computer sector, that have allowed the application of the technologies CAD-CAM, also in dentistry (2-5, 11). These systematics have allowed us to get "automatically" structures for dental prosthesis, starting from the scanning of the die and passing for an intermediary phase of computerized planning (CAD, computer aided design), through numerical control millers (CAM, computer aided manufacturing), enslaved to calculating the electronic that drives the movement of it. The aim of this work is therefore that to analyze and to describe the systematic computerized 3SHAPE verifying the degree of precision, through the analysis of the obtainable marginal closing with the zirconia frameworks.

16.
Oral Implantol (Rome) ; 1(3-4): 124-30, 2008 Oct.
Article in English | MEDLINE | ID: mdl-23285348

ABSTRACT

In this case report of monoedentulia we will deal with the positioning o fan upper jaw implant in zone 2.6. In such surgery the strategy of a flapless (1, 2) operation with minimum invasive approach has allowed u sto combine both the aesthetic and functionality with an immediate provisional rehabilitation, thus saving recuperation time and trouble for the patient (3).Multidisciplinary character of the execution of this clinical case is underlined, where we associate the knowleadge of conservatori of the prosthetic; always maintaining respect for the canons of gnatology which must not be left out of consideration.

17.
J Agric Food Chem ; 49(11): 5397-408, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11714334

ABSTRACT

Experiments were designed to demonstrate the actual contribution of yeast in the formation of the primary aroma during the vinification of neutral grapes. Ruché was chosen as the model wine to study because of its unique fragrance. A yeast strain specific for Ruché was selected using a new and rapid isolation method for red wines. The results of this study can be summarized as follows: Skins from nonaromatic white or red grapes apparently contain most of the primary aroma compounds that are revealed in the must only after contact with yeast cells under defined conditions. Similar results were obtained with the pulp and seeds fractions; however, the olfactory notes, although well characterized, differed from those obtained with skins alone. Clarification, filtration, and centrifugation of the pulp and seed fractions or sonification of the skins produce different and well-characterized olfaction notes during the contact with yeast. The primary aroma of nonaromatic white and red grapes contained in the skins can be revealed within 24-48 h of yeast contact in a synthetic nutrient medium (SNM). The primary aroma precursors extracted from the skins with methanol, water-saturated butanol, or aqueous buffer at pH 3.2, concentrated and eluted from a C18 resin column, can be transformed to the free form wine aroma markers within 6 h of contact with yeast cells in SNM. By contrast, prolonged maceration of the skins in aqueous alcoholic buffer at pH 3.2 or 1.1, at 50 or 70 degrees C did not release primary odors typical of wine. The individual primary aroma compounds, identified by GC-MS analysis in Ruché wine samples or in Ruché skin-yeast-SNM samples, could not explain the complexity of the typical Ruché wine odor. Only odors common to many wine varieties were identified by GC-olfactometry analysis.


Subject(s)
Fruit/metabolism , Odorants , Saccharomyces cerevisiae/physiology , Volatilization , Wine
18.
Biochem Biophys Res Commun ; 281(2): 300-4, 2001 Feb 23.
Article in English | MEDLINE | ID: mdl-11181045

ABSTRACT

This work provides evidence that nicotine (1 x 10(-5) M) can cause changes in the intracellular calcium concentration of Trypanosoma cruzi epimastigotes, which can be blocked by alpha-bungarotoxin but not by atropine. Moreover, parasite membranes also bind such nicotinic acetylcholine receptor antagonist as well as agonists such as carbamylcholine (IC(50): 7.6 x 10(-7) M) and nicotine (IC(50): 1 x 10(-7) M). Results suggest that there is a molecular species in the surface of the parasite able to bind nicotinic ligands; therefore, nicotine interaction could lead to the activation of the mechanisms involved in intracellular calcium concentration increase in the parasite.


Subject(s)
Calcium/metabolism , Cholinergic Agonists/metabolism , Nicotine/pharmacology , Trypanosoma cruzi/drug effects , Animals , Binding, Competitive/drug effects , Bungarotoxins/metabolism , Calcium Signaling , Carbachol/metabolism , Carbachol/pharmacology , Dose-Response Relationship, Drug , Fura-2 , Membranes/drug effects , Membranes/metabolism , Nicotine/metabolism , Trypanosoma cruzi/metabolism
19.
Neurochem Int ; 36(1): 27-33, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10566956

ABSTRACT

We have previously shown that two histidine residues of the nicotinic acetylcholine receptor are relevant for alpha-bungarotoxin binding. This paper studies: (1) the interaction between alpha-bungarotoxin and the peptide alpha173-202--synthesized according to the sequence of the Torpedo californica receptor alpha subunit--and between the toxin and the same peptide containing His186 modified with ethoxyformic anhydride or substituted by Ala; (2) the influence of the presence of Cys192-Cys193 disulfide bridge on such interactions. Solid-phase and in-solution competition assays were performed: ethoxyformylation of His186 or its substitution by Ala led to a significant drop in the toxin binding capacity only for peptides containing the bridge. Circular dichroism and fourth derivate spectra of all peptides were also analyzed. Results strongly indicate the involvement of His186 in the toxin binding to those peptides with the bridge--also present in the native receptor molecules--but not to their reduced forms; on the other hand, they give further support to the already established premise that, though the bridge does not participate directly in receptor-toxin binding, its presence is relevant to define the appropriate conformation of the interaction area.


Subject(s)
Bungarotoxins/pharmacokinetics , Histidine , Receptors, Nicotinic/chemistry , Receptors, Nicotinic/metabolism , Amino Acid Sequence , Animals , Binding Sites , Binding, Competitive , Circular Dichroism , Disulfides , Electric Organ , Kinetics , Molecular Sequence Data , Peptide Fragments/chemistry , Protein Conformation , Receptors, Nicotinic/isolation & purification , Torpedo , alpha7 Nicotinic Acetylcholine Receptor
20.
Neurosci Lett ; 274(3): 195-8, 1999 Oct 29.
Article in English | MEDLINE | ID: mdl-10548423

ABSTRACT

Olfactory nerve axons terminate in rounded regions of the olfactory bulb, termed glomeruli, where they make excitatory synapses with the dendrites of second-order neurons. Neurotransmission from the olfactory nerve to the postsynaptic targets is negatively regulated by gamma-aminobutyric acid (GABA), and there is evidence that inhibition of sensory input is mediated, at least in part, by GABA(B) receptors. Using an antiserum that recognizes two GABA(B) receptor splice variants (GBR1a and GBR1b), we show here that GABA(B) receptors are located on the axon terminals of the olfactory nerve, where they are concentrated at sites of axodendritic apposition. Taken with previous data, these results indicate that GABA(B) receptors act presynaptically to regulate the release of glutamate from olfactory nerve terminals.


Subject(s)
Olfactory Bulb/chemistry , Presynaptic Terminals/chemistry , Receptors, GABA-B/analysis , Alternative Splicing/physiology , Animals , Antibody Specificity , Fluorescent Antibody Technique , Glutamic Acid/metabolism , Olfactory Bulb/metabolism , Presynaptic Terminals/metabolism , Rats , Receptors, GABA-B/genetics , Receptors, GABA-B/immunology , Receptors, Metabotropic Glutamate/metabolism
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