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1.
O.F.I.L ; 32(1): 83-86, enero 2022.
Article in Spanish | IBECS | ID: ibc-205737

ABSTRACT

Introducción: La infestación y mortalidad ocasionada por el coronavirus Sarv-Cov-2 (COVID-19) generó que los sistemas de salud desarrollaran acciones para promover nuevas investigaciones clínicas encaminadas a contar con esquemas de tratamientos efectivos, para un mejor manejo de esta enfermedad.En Cuba, con la existencia antes de la pandemia, de un plan de ensayos clínicos y la necesidad de promover nuevos, para hacer frente a la COVID-19; se propuso la elaboración de un sistema de acciones encaminadas a preservar la calidad de los mismos.Objetivo: Describir las principales acciones desarrolladas, por el Sistema Nacional de Salud cubano, para el desarrollo de las investigaciones clínicas durante la pandemia.Métodos: Se realizó una revisión bibliográfica en los principales sitios web regulatorios y vinculados con el tema de investigaciones clínicas en etapa de pandemia por la COVID-19. Los resultados alcanzados se tuvieron en cuenta para proponer un sistema de acciones propio, encaminado a respaldar los ensayos clínicos.Resultados: Se establecieron acciones en tres líneas de trabajo: el respaldo ético, los requerimientos regulatorios para las modificaciones a los estudios en curso y nuevos y para el control de los ensayos clínicos. El sistema de trabajo quedó conformado por 29 acciones encaminadas a que los ensayos clínicos tuvieran un respaldado ético, cumplieran con los requerimientos regulatorios en cuanto a los aspectos metodológicos, de diseño y de control para garantizar el cumplimiento de las Buenas Prácticas Clínicas. (AU)


Introduction: The infestation and mortality caused by the Sarv-Cov-2 (COVID-19) coronavirus led health systems to develop actions to promote new clinical research aimed at having effective treatment schemes for better management of this disease.In Cuba, with the existence before the pandemic, of a clinical trial plan and the need to promote new ones, to deal with COVID-19; it was proposed to develop a system of actions aimed at preserving their quality.Objective: Describe the main actions developed by the Cuban National Health System for the development of clinical research during the pandemic.Methods: A bibliographic review was carried out on the main regulatory websites and those related to the topic of clinical research in the pandemic stage of COVID-19. The results achieved were taken into account to propose an own action system, aimed at supporting clinical trials.Results: Actions were established in three lines of work: ethical support, regulatory requirements for modifications to ongoing and new studies, and the control of clinical trials. The work system was made up of 29 actions aimed at ensuring that clinical trials have ethical support, comply with regulatory requirements in terms of methodological, design aspects and their control to guarantee compliance with Good Clinical Practices. (AU)


Subject(s)
Humans , Health Systems , Coronavirus , Pandemics , Clinical Clerkship , Pathology
2.
Phys Chem Chem Phys ; 21(18): 9277-9284, 2019 May 08.
Article in English | MEDLINE | ID: mdl-31020288

ABSTRACT

The concept of coordination sphere (CS) is central to the rational development of hierarchical molecular assemblies in modern chemistry. Manipulating the organization around transition metal ions with covalent and supramolecular interactions is a general strategy that underlies most synthetic protocols. Achieving similar control for photoexcited molecular complexes is necessary to advance the design of light-driven functionalities. This objective calls for monitoring the ultrafast dynamics of the primary (1-CS) and the secondary (2-CS) coordination spheres on the atomic scale, which remains to date an important experimental challenge for short-lived species. In this work, transient wide-angle scattering of hard X-rays (25 keV) is employed with state-of-the-art AIMD simulations in order to visualize the 1-CS (solute-only) and the 2-CS (solvation cage) of the photoinduced high-spin (HS) state for [Fe(bpy)3]2+ (bpy = 2,2'-bipyridine) in aqueous solution. Correlating this structural information in real-space reveals the interlacing of the two CS, which in turn explains why solvation affects the photoinduced electronic and structural dynamics in this class of complexes. More generally, these results obtained for a prominent prototypical system in ultrafast X-ray sciences demonstrate the unique perspectives offered by this technique to gain the crucial knowledge about the multiscale solvation dynamics that is currently missing for controlling the solute-solvent interactions in advanced functional nano and biomaterials employed for photoconversion.

3.
Updates Surg ; 68(2): 199-203, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26951523

ABSTRACT

Prosthetic mesh rolled up and fixed with stitches like a slim cigarette ("slim-mesh") for laparoscopic ventral hernia (VH) repair is an new technique which allows an easy intraperitoneally introduction, distension and circumferential fixation of a prosthetic mesh without transabdominal fixation sutures even for meshes larger than 16 cm up to 30 cm for the "slim-mesh" repair of wide ventral hernias. We report the technique of laparoscopic repair of VH with "slim-mesh". This technique enables an easy intra-peritoneally introduction of the mesh through the trocar because it reduces consistently its size, it allows a rapid intra-abdominal handling of the mesh and a fast and easy fixation for VH repair. The average time of surgery with "slim-mesh" for treatment of all 28 VH was 97 min ranging from 57 to 160 min. The average time for the repair of the 24 VH smaller than 10 cm was 91 and 135 min for the four VH larger than 10-22 cm. This new surgical technique leads to a reduction of surgical risks avoiding the use of transfascial sutures with the associated complications. This new surgical procedure in our experience is fast, safe, simple and also easily reproducible by surgeons in laparoscopic training. This technique may be used in wide VH (larger than 10-22 cm) that generally require open surgery.


Subject(s)
Hernia, Ventral/surgery , Herniorrhaphy/methods , Laparoscopy/methods , Surgical Mesh , Humans , Prosthesis Design , Suture Techniques
4.
Nat Commun ; 7: 10566, 2016 Feb 18.
Article in English | MEDLINE | ID: mdl-26887682

ABSTRACT

Electron dynamics induced by resonant absorption of light is of fundamental importance in nature and has been the subject of countless studies in many scientific areas. Above the ionization threshold of atomic or molecular systems, the presence of discrete states leads to autoionization, which is an interference between two quantum paths: direct ionization and excitation of the discrete state coupled to the continuum. Traditionally studied with synchrotron radiation, the probability for autoionization exhibits a universal Fano intensity profile as a function of excitation energy. However, without additional phase information, the full temporal dynamics cannot be recovered. Here we use tunable attosecond pulses combined with weak infrared radiation in an interferometric setup to measure not only the intensity but also the phase variation of the photoionization amplitude across an autoionization resonance in argon. The phase variation can be used as a fingerprint of the interactions between the discrete state and the ionization continua, indicating a new route towards monitoring electron correlations in time.

5.
Faraday Discuss ; 185: 51-68, 2015.
Article in English | MEDLINE | ID: mdl-26400760

ABSTRACT

The photochemical reactions performed by transition metal complexes have been proposed as viable routes towards solar energy conversion and storage into other forms that can be conveniently used in our everyday applications. In order to develop efficient materials, it is necessary to identify, characterize and optimize the elementary steps of the entire process on the atomic scale. To this end, we have studied the photoinduced electronic and structural dynamics in two heterobimetallic ruthenium-cobalt dyads, which belong to the large family of donor-bridge-acceptor systems. Using a combination of ultrafast optical and X-ray absorption spectroscopies, we can clock the light-driven electron transfer processes with element and spin sensitivity. In addition, the changes in local structure around the two metal centers are monitored. These experiments show that the nature of the connecting bridge is decisive for controlling the forward and the backward electron transfer rates, a result supported by quantum chemistry calculations. More generally, this work illustrates how ultrafast optical and X-ray techniques can disentangle the influence of spin, electronic and nuclear factors on the intramolecular electron transfer process. Finally, some implications for further improving the design of bridged sensitizer-catalysts utilizing the presented methodology are outlined.


Subject(s)
Electrons , Quantum Theory , Solar Energy , Coordination Complexes/chemistry , Models, Molecular , Ruthenium/chemistry , Sunlight
6.
Obes Surg ; 25(1): 174-9, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25398551

ABSTRACT

BACKGROUND: We report our initial gastric electrical stimulation experience using the abiliti® system for the treatment of obese patients followed for 1 year. METHOD: Between March 2011 and June 2013, 27 obese patients (BMI 30 to 46 kg/m(2)) were enrolled in a prospective open label study and implanted with a gastric stimulator. The patients were provided with nutritional support, and sensor-based behavioral feedback. RESULTS: At 12 months, percent excess weight loss (%EWL) obtained was 49.3 ± 19.2 % with no significant differences between gender or age sub-groups. The %EWL data were segmented into two groups according to BMI 30-40 kg/m(2) patients (obesity grade I and II) and BMI >40 kg/m(2), with the results of weight loss being significantly higher for the lower BMI group (59.1 ± 19.5 vs. 46.7 ± 13.4, respectively, p < 0.01). One subject requested to have his device explanted, and the minor postoperative adverse events were resolved without hospital admission. All patients experienced early satiety and reduced their intake. CONCLUSIONS: After 12 months of follow-up, gastric electrical stimulation treatment appears to be a safe and effective option for weight loss in obese subjects. Long-term follow-up and further studies are warranted.


Subject(s)
Biosensing Techniques/instrumentation , Electric Stimulation Therapy/instrumentation , Electric Stimulation Therapy/methods , Obesity/therapy , Prostheses and Implants , Stomach/surgery , Adult , Body Mass Index , Equipment Design , Female , Follow-Up Studies , Humans , Male , Meals , Middle Aged , Pilot Projects , Weight Loss/physiology
7.
Phys Rev Lett ; 110(13): 138302, 2013 Mar 29.
Article in English | MEDLINE | ID: mdl-23581383

ABSTRACT

This work presents an x-ray absorption measurement by use of ionizing radiation generated by a femtosecond pulsed laser source. The spectrometer was a microcalorimetric array whose pixels are capable of accurately measuring energies of individual radiation quanta. An isotropic continuum x-ray spectrum in the few-keV range was generated from a laser plasma source with a water-jet target. X rays were transmitted through a ferrocene powder sample to the detector, whose pixels have average photon energy resolution ΔE=3.14 eV full-width-at-half-maximum at 5.9 keV. The bond distance of ferrocene was retrieved from this first hard-x-ray absorption fine-structure spectrum collected with an energy-dispersive detector. This technique will be broadly enabling for time-resolved observations of structural dynamics in photoactive systems.

8.
J Phys Chem A ; 116(40): 9878-87, 2012 Oct 11.
Article in English | MEDLINE | ID: mdl-22970732

ABSTRACT

We have studied the photoinduced low spin (LS) to high spin (HS) conversion of [Fe(bipy)(3)](2+) in aqueous solution. In a laser pump/X-ray probe synchrotron setup permitting simultaneous, time-resolved X-ray diffuse scattering (XDS) and X-ray spectroscopic measurements at a 3.26 MHz repetition rate, we observed the interplay between intramolecular dynamics and the intermolecular caging solvent response with better than 100 ps time resolution. On this time scale, the initial ultrafast spin transition and the associated intramolecular geometric structure changes are long completed, as is the solvent heating due to the initial energy dissipation from the excited HS molecule. Combining information from X-ray emission spectroscopy and scattering, the excitation fraction as well as the temperature and density changes of the solvent can be closely followed on the subnanosecond time scale of the HS lifetime, allowing the detection of an ultrafast change in bulk solvent density. An analysis approach directly utilizing the spectroscopic data in the XDS analysis effectively reduces the number of free parameters, and both combined permit extraction of information about the ultrafast structural dynamics of the caging solvent, in particular, a decrease in the number of water molecules in the first solvation shell is inferred, as predicted by recent theoretical work.


Subject(s)
Ferric Compounds/chemistry , Quantum Theory , Thermodynamics , Kinetics , Photochemical Processes , Spectrometry, X-Ray Emission , Time Factors , Water/chemistry , X-Ray Diffraction
9.
J Chem Phys ; 134(9): 094511, 2011 Mar 07.
Article in English | MEDLINE | ID: mdl-21384989

ABSTRACT

Plasmons are investigated in free nanoscale Na, Mg, and K metal clusters using synchrotron radiation-based x-ray photoelectron spectroscopy. The core levels for which the response from bulk and surface atoms can be resolved are probed over an extended binding energy range to include the plasmon loss features. In all species the features due to fundamental plasmons are identified, and in Na and K also those due to either the first order plasmon overtones or sequential plasmon excitation are observed. These features are discussed in view of earlier results for planar macroscopic samples and free clusters of the same materials.

10.
Phys Rev Lett ; 103(14): 143001, 2009 Oct 02.
Article in English | MEDLINE | ID: mdl-19905566

ABSTRACT

The cooling rates of C60- have been measured in an electrostatic storage ring between several hundred mus and several tens of ms with one-photon laser excitation. The absolute energy scale is established by the photon energy, and the cooling time interval is derived from the nonexponential decay of the ensemble of hot molecules. The energy decreases due to the combined action of depletion and thermal emission of IR photons with a total energy loss rate that varies inversely proportional to time, 0.9 eV/t. The radiative component decreases from a few hundred eV/s at submillisecond time scales to several tens of eV/s at 20 ms and confirms that the crossover from depletion to predominantly radiative cooling occurs around 5 ms. The method is applicable to any large molecule or cluster which decays spontaneously, irrespective of the specific decay channel.

11.
J Chem Phys ; 131(1): 014301, 2009 Jul 07.
Article in English | MEDLINE | ID: mdl-19586099

ABSTRACT

We present a detailed study of the electronic structure and the stability of C(60) dianions in the gas phase. Monoanions were extracted from a plasma source and converted to dianions by electron transfer in a Na vapor cell. The dianions were then stored in an electrostatic ring, and their near-infrared absorption spectrum was measured by observation of laser induced electron detachment. From the time dependence of the detachment after photon absorption, we conclude that the reaction has contributions from both direct electron tunneling to the continuum and vibrationally assisted tunneling after internal conversion. This implies that the height of the Coulomb barrier confining the attached electrons is at least approximately 1.5 eV. For C(60)(2-) ions in solution electron spin resonance measurements have indicated a singlet ground state, and from the similarity of the absorption spectra we conclude that also the ground state of isolated C(60)(2-) ions is singlet. The observed spectrum corresponds to an electronic transition from a t(1u) lowest unoccupied molecular orbital (LUMO) of C(60) to the t(1g) LUMO+1 level. The electronic levels of the dianion are split due to Jahn-Teller coupling to quadrupole deformations of the molecule, and a main absorption band at 10,723 cm(-1) corresponds to a transition between the Jahn-Teller ground states. Also transitions from pseudorotational states with 200 cm(-1) and (probably) 420 cm(-1) excitation are observed. We argue that a very broad absorption band from about 11,500 cm(-1) to 13,500 cm(-1) consists of transitions to so-called cone states, which are Jahn-Teller states on a higher potential-energy surface, stabilized by a pseudorotational angular momentum barrier. A previously observed, high-lying absorption band for C(60)(-) may also be a transition to a cone state.

12.
J Chem Phys ; 131(24): 244305, 2009 Dec 28.
Article in English | MEDLINE | ID: mdl-20059071

ABSTRACT

The study focuses on the rapid geometry change in ethyne excited near the carbon 1s edge. Core excitation and ionization lead to population of dicationic states in ethyne. We study three competing dissociation pathways associated with deprotonation in the linear ethyne molecule, and two cases of rapid proton migration. We investigate the alignment of the molecule in the excited state and find startling differences in these three cases. We present evidence for a strong anisotropy in the production of H(2)(+)/C(2)(+) fragments through a rapid deformation of the molecule to a dibridged conformation with the transition dipole moment parallel to the polarization of the exciting radiation.

13.
Aliment Pharmacol Ther ; 23(8): 1161-70, 2006 Apr 15.
Article in English | MEDLINE | ID: mdl-16611277

ABSTRACT

AIMS: To assess how much patients with hepatitis C virus infection know about their condition and what impact it has on their lifestyle. MATERIALS AND METHODS: A multiple-choice questionnaire was administered anonymously to 364 hepatitis C virus-infected subjects just before their first specialist visit. RESULTS: Even before hepatitis C virus infection was diagnosed, 257 subjects (70.6%) already knew something about this infection. Overall, 36% of patients had changed the way they behaved within the family, 25.5% had changed their sexual habits, 46.9% had changed their diet, and 69% reported having stopped or limited their alcohol intake after being told they were hepatitis C virus positive. Hepatitis C virus infection had a negative impact on the psychological status in 44.2% of patients. This effect was significantly greater among women and was independent of either the duration of their infection or any counselling received from the general practitioner. The need for specific treatment was reported by 59.8%. A demand for more detailed information about hepatitis C virus was expressed by 89.9% of patients. CONCLUSIONS: Hepatitis C virus changes all aspects of lifestyle and psychological status. The patients' strong demand for more information suggests that counselling and educational programmes must be an integral part of the activities of both the general practitioner and the specialist.


Subject(s)
Comprehension , Hepatitis C/psychology , Life Style , Adolescent , Adult , Aged , Aged, 80 and over , Alcohol Drinking , Chi-Square Distribution , Cohort Studies , Diet , Female , Health Knowledge, Attitudes, Practice , Humans , Male , Middle Aged , Patient Education as Topic , Risk-Taking , Sexual Behavior , Surveys and Questionnaires
14.
Phys Rev Lett ; 92(23): 233002, 2004 Jun 11.
Article in English | MEDLINE | ID: mdl-15245155

ABSTRACT

Completely fine-structure-resolved photoelectron spectra produced from sodium atoms selectively excited into the Na* 2p(6)3p (2)P(1/2) and (2)P(3/2) states were obtained using a third generation synchrotron source in conjunction with laser pumping and high-resolution spectrometry. The spectra show dramatically different behaviors. The strong variations observed in the regions of the Na+ 2p(5)3p (1,3)L(J) photolines and the Na+ 2p(5)4p (1,3)L(J) shakeup satellites are explained within a generalized geometrical model, accounting for the intermediate angular momentum coupling in the ionic states.

15.
Phys Rev Lett ; 92(1): 013001, 2004 Jan 09.
Article in English | MEDLINE | ID: mdl-14753986

ABSTRACT

Angle- and spin-resolved photoelectron spectroscopy with linearly and circularly polarized synchrotron radiation were used to study the electronic structure of model triatomic molecules, hydrogen sulfide, and carbonyl sulfide. The spin-polarization measurements of the molecular field split components of the S 2p photolines revealed a strong effect of the different molecular environments. The validity of simple atomic models to explain the results is discussed.

16.
Phys Rev Lett ; 89(4): 045502, 2002 Jul 22.
Article in English | MEDLINE | ID: mdl-12144488

ABSTRACT

Detailed analysis of the highest occupied molecular orbital band shape in the photoelectron spectrum of gaseous C60 reveals a dynamic Jahn-Teller effect in the ground state of C60(+). The direct observation of three tunneling states asserts a D(3d) geometry for the isolated cation, originating from a strong vibronic coupling. These results show that the ionic motion plays an important role in the electron-phonon interaction.

17.
Health Policy Plan ; 13(4): 446-58, 1998 Dec.
Article in English | MEDLINE | ID: mdl-10346036

ABSTRACT

One of the primary obstacles in the implementation of continuous quality improvement (CQI) programmes in developing countries is the lack of timely and appropriate information for decentralized decision-making. The integrated quality information system (QIS) described herein demonstrates Mexico's unique effort to package four separate, yet mutually reinforcing, tools for the generation and use of quality-related information at all levels of the Mexican national health care system. The QIS is one element of the continuous quality improvement programme administered by the Secretariat of Health in Mexico. Mexico's QIS was designed to be flexible and capable of adapting to local needs, while at the same time allowing for the standardization of health care quality assurance indicators, and subsequent ability to measure and compare the quality performance of health facilities nationwide. The flexibility of the system extends to permit the optimal use of available data by health care managers at all levels of the health care system, as well as the generation of new information in important areas often neglected in more traditional information systems. Mexico's QIS consists of four integrated components: 1) a set of client and provider surveys, to assess specific issues in the quality of health services delivered; 2) client and provider national satisfaction surveys; 3) a sentinel health events strategy; and 4) a national Comparative Performance Evaluation System, for use by the Secretariate of Health for the quality assessment of state and provincial health care services (internal benchmarking). The QIS represents another step in Mexico's ongoing effort to use data for effective decision-making in the planning, monitoring and evaluation of services delivered by the national health care system. The design and application of Mexico's QIS provides a model for decentralized decision-making that could prove useful for developing countries, where the effective use of quality indicators is often limited. Further, the system could serve as a mechanism for motivating positive change in the way information is collected and used in the process of ensuring high quality health care service delivery.


Subject(s)
Management Information Systems , Public Health Administration/standards , Total Quality Management , Benchmarking , Data Collection , Developing Countries , Evaluation Studies as Topic , Mexico , Organizational Case Studies , Quality Indicators, Health Care
18.
Salud Publica Mex ; 37(1): 12-8, 1995.
Article in Spanish | MEDLINE | ID: mdl-7754424

ABSTRACT

A census of private health establishments was carried out by the Secretary of Health, in order to quantify its resources and to describe their geographical distribution. The census, conducted in 1994, was limited to private units which offered hospitalization services, and the reference period was the previous year. Results showed that there are 2,723 private hospitalization units in Mexico, and nearly a half of the units are concentrated in the Federal District, and the states of Mexico, Guanajuato, Michoacán, Baja California and Veracruz. The number of private hospitalization beds registered in the country are 33,937, these figures indicate that private medicine is the main hospital care provider in the national health system. Similar results were obtained regarding other material and human resources. It is important to stress the need for further research regarding the role of private medicine in Mexico, including aspects related to the quality of the services being provided.


Subject(s)
Hospital Units/supply & distribution , Hospitals, Private/supply & distribution , Private Practice , Data Collection/statistics & numerical data , Hospital Bed Capacity/statistics & numerical data , Hospital Units/statistics & numerical data , Hospitals, Private/statistics & numerical data , Humans , Mexico , Private Practice/statistics & numerical data , Workforce
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