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1.
IFAC Pap OnLine ; 54(15): 151-156, 2021.
Article in English | MEDLINE | ID: mdl-38620952

ABSTRACT

In order to analyze the effect of vaccination in a population with the presence of viruses, a variation of the SIR (Susceptible-Infected-Removed) model is proposed taking into account social distancing and the effect of the vaccine. The equilibrium points of the proposed model are calculated and the stability analysis of the system is carried out. For the proposed model, disease-free equilibrium point and endemic equilibrium point are found and the conditions of existence are discussed. For the disease-free equilibrium point the bifurcation conditions are derived and simulations show that reducing the vaccination effort can lead the disease-free equilibrium to the endemic equilibrium. From the theoretical analysis, a minimum value of effort is obtained to guarantee a disease-free equilibrium point. Simulations were carried out from the value obtained from Rv to validate the theoretical results.

2.
Rev Sci Instrum ; 87(11): 11E510, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27910648

ABSTRACT

An optical Thomson scattering diagnostic has been designed for the National Ignition Facility to characterize under-dense plasmas. We report on the design of the system and the expected performance for different target configurations. The diagnostic is designed to spatially and temporally resolve the Thomson scattered light from laser driven targets. The diagnostic will collect scattered light from a 50 × 50 × 200 µm volume. The optical design allows operation with different probe laser wavelengths. A deep-UV probe beam (λ0 = 210 nm) will be used to Thomson scatter from electron plasma densities of ∼5 × 1020 cm-3 while a 3ω probe will be used for plasma densities of ∼1 × 1019 cm-3. The diagnostic package contains two spectrometers: the first to resolve Thomson scattering from ion acoustic wave fluctuations and the second to resolve scattering from electron plasma wave fluctuations. Expected signal levels relative to background will be presented for typical target configurations (hohlraums and a planar foil).

3.
Rev Sci Instrum ; 87(11): 11E549, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27910656

ABSTRACT

The National Ignition Facility (NIF) is a 192 laser beam facility designed to support the Stockpile Stewardship, High Energy Density and Inertial Confinement Fusion (ICF) programs. We report on the design of an Optical Thomson Scattering (OTS) diagnostic that has the potential to transform the community's understanding of NIF hohlraum physics by providing first principle, local, time-resolved measurements of under-dense plasma conditions. The system design allows operation with different probe laser wavelengths by manual selection of the appropriate beam splitter and gratings before the shot. A deep-UV probe beam (λ0-210 nm) will be used to optimize the scattered signal for plasma densities of 5 × 1020 electrons/cm3 while a 3ω probe will be used for experiments investigating lower density plasmas of 1 × 1019 electrons/cm3. We report the phase I design of a two phase design strategy. Phase I includes the OTS telescope, spectrometer, and streak camera; these will be used to assess the background levels at NIF. Phase II will include the design and installation of a probe laser.

4.
Trop Biomed ; 29(3): 360-5, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23018498

ABSTRACT

The purpose of this study is to determine the relevance of the hygiene hypothesis; that is to determine if worm infestation has a protective role against the development of allergic rhinitis. A prospective case controlled study was conducted. Specific IgG levels to Toxocara were studied in 85 patients confirmed to have allergic rhinitis and were compared to levels in another 85 controls, with no form of allergy. The IgG assay was done using ELISA technique. There was a higher incidence of positive specific IgG to Toxocara in the controls as compared to allergic patients. The values were statistically significant [Chi square test (p=0.002)]. This negative association between worm infestation and allergic rhinitis suggests that a previous worm infestation could protect against the development of allergic rhinitis.


Subject(s)
Larva Migrans, Visceral/parasitology , Rhinitis, Allergic, Perennial/immunology , Toxocara canis/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Animals , Antigens, Helminth/blood , Case-Control Studies , Child , Enzyme-Linked Immunosorbent Assay , Humans , Immunoglobulin E/blood , Immunoglobulin G/blood , Incidence , Larva Migrans, Visceral/complications , Larva Migrans, Visceral/epidemiology , Longitudinal Studies , Middle Aged , Occupations , Prevalence , Prospective Studies , Rhinitis, Allergic , Rhinitis, Allergic, Perennial/parasitology , Young Adult
5.
Tropical Biomedicine ; : 360-365, 2012.
Article in English | WPRIM (Western Pacific) | ID: wpr-630175

ABSTRACT

The purpose of this study is to determine the relevance of the hygiene hypothesis; that is to determine if worm infestation has a protective role against the development of allergic rhinitis. A prospective case controlled study was conducted. Specific IgG levels to Toxocara were studied in 85 patients confirmed to have allergic rhinitis and were compared to levels in another 85 controls, with no form of allergy. The IgG assay was done using ELISA technique. There was a higher incidence of positive specific IgG to Toxocara in the controls as compared to allergic patients. The values were statistically significant [Chi square test (p=0.002)]. This negative association between worm infestation and allergic rhinitis suggests that a previous worm infestation could protect against the development of allergic rhinitis.

6.
Aesthetic Plast Surg ; 26(4): 233-8, 2002.
Article in English | MEDLINE | ID: mdl-12397444

ABSTRACT

Botulin toxin is a strong blocking agent which has shown great usefulness in a variety of neuromuscular disorders related to hypertonicity and spasticity. Since 1992 it has been used in the attenuation of facial wrinkles. In this article we describe the different applications in the upper third, middle third, and lower third of the face, as well as the platysmal bands of the neck. We emphasize the use of this procedure for the upper third of the face. Limits are indicated when it is used on the middle and lower parts of the face. The author has found excellent results in the attenuation of wrinkles of the neck region.


Subject(s)
Botulinum Toxins, Type A/therapeutic use , Neuromuscular Agents/therapeutic use , Skin Aging/drug effects , Animals , Blepharospasm/drug therapy , Botulinum Toxins, Type A/adverse effects , Botulinum Toxins, Type A/isolation & purification , Face , Female , Humans , Mice , Neck , Neuromuscular Agents/adverse effects , Neuromuscular Agents/isolation & purification , Treatment Outcome
7.
Nexo rev. Hosp. Ital. B.Aires ; 19(1): 27-33, mayo 1999. ilus
Article in Spanish | LILACS | ID: lil-267602

ABSTRACT

La Toxina Botulínica (BOTOX) es un potente agente bloqueante que ha demostrado su gran utilidad en una amplia variedad de desórdenes neuromusculares asociados con hipertonía y espasticidad. Dicha toxina, y especialmente el serotipo A, también ha sido reconocida como beneficiosa en la corrección de arrugas faciales del tercio superior de la cara, siendo aprobado su uso médico por la FDA de los Estados Unidos desde 1979. Se ha comprobado que su acción es producida por una denervación química a nivel de la placa neuromuscular; dicho efecto es temporario (neurogénesis) y selectivo (para un músculo determinado). Aún siendo los riesgos despreciables, es aconsejable que el BOTOX sea administrado por médicos, quienes tengan un conocimiento profundo de la anatomía regional, fisiología y efectos clínicos de la toxina así como sus limitaciones y complicaciones


Subject(s)
Humans , Botulinum Toxins, Type A/administration & dosage , Botulinum Toxins, Type A/pharmacokinetics , Botulinum Toxins, Type A/pharmacology , Botulinum Toxins, Type A/immunology , Botulinum Toxins, Type A/therapeutic use , Skin Aging/drug effects , Surgery, Plastic
8.
Nexo rev. Hosp. Ital. B.Aires ; 19(1): 27-33, mayo 1999. ilus
Article in Spanish | BINACIS | ID: bin-12016

ABSTRACT

La Toxina Botulínica (BOTOX) es un potente agente bloqueante que ha demostrado su gran utilidad en una amplia variedad de desórdenes neuromusculares asociados con hipertonía y espasticidad. Dicha toxina, y especialmente el serotipo A, también ha sido reconocida como beneficiosa en la corrección de arrugas faciales del tercio superior de la cara, siendo aprobado su uso médico por la FDA de los Estados Unidos desde 1979. Se ha comprobado que su acción es producida por una denervación química a nivel de la placa neuromuscular; dicho efecto es temporario (neurogénesis) y selectivo (para un músculo determinado). Aún siendo los riesgos despreciables, es aconsejable que el BOTOX sea administrado por médicos, quienes tengan un conocimiento profundo de la anatomía regional, fisiología y efectos clínicos de la toxina así como sus limitaciones y complicaciones


Subject(s)
Humans , Botulinum Toxins, Type A/therapeutic use , Botulinum Toxins, Type A/pharmacology , Botulinum Toxins, Type A/administration & dosage , Botulinum Toxins, Type A/immunology , Botulinum Toxins, Type A/pharmacokinetics , Skin Aging/drug effects , Surgery, Plastic
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