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1.
Radiologia (Engl Ed) ; 66(3): 219-227, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38908883

RESUMO

INTRODUCTION: Transfontanellar brain ultrasound is an essential tool for monitoring the size of the ventricles in preterm neonates and has many advantages over other alternative diagnostic techniques, including its accessibility and non-use of ionizing radiation. When considering the normal ventricular size, it is essential to have reference measurements based on age-matched populations. The objective of this article is to present our reference measures, based on a sample of preterm infants that we have studied. METHODS: A retrospective observational study was conducted. Measurements of the Levene index, frontal horn thickness, and Evans index were obtained in preterm neonates from 25 to 45 weeks, over a period of 5 years, between January 2016 and December 2020. After applying the exclusion criteria, a sample of 199 patients and 350 ultrasound scans were obtained. The independent samples t-test and the Mann-Whitney test were used for the comparison of samples. RESULTS: The distribution of the right and left Levene indices was normal (Shapiro-Wilk test with p = 0.16 and 0.05, respectively), unlike the thickness distribution of the frontal horns (p < 0.05 on both sides). No significant differences were detected between the sexes (p = 0.08). A linear correlation was found between the biparietal diameter and the Levene index. CONCLUSION: From the results obtained in our study, we present reference tables for ventricular size, with the 3rd, 25th, 50th, 75th, and 97th, being the first ones made in our country.


Assuntos
Ventrículos Cerebrais , Recém-Nascido Prematuro , Nomogramas , Humanos , Estudos Retrospectivos , Feminino , Masculino , Recém-Nascido , Ventrículos Cerebrais/diagnóstico por imagem , Ventrículos Cerebrais/anatomia & histologia , Valores de Referência , Tamanho do Órgão , Ultrassonografia/métodos
2.
Occup Med (Lond) ; 74(3): 218-224, 2024 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-38527057

RESUMO

BACKGROUND: Occupational footwear is intended to provide protection against the risks associated with work activities. The choice of footwear is complex due to the welfare, health and safety conditions of workers. AIMS: To identify the injuries and problems caused by occupational footwear through a systematic review of the existing literature. METHODS: A literature search was carried out in the Cumulative Index to Nursing and Allied Health Literature, Dialnet Plus, Pubmed, Scientific Electronic Library Online, Medline, Scopus and Web of Science databases over the period 2000-23, following the PRISMA Declaration guidelines. RESULTS: A total of 27 studies were included in the review. The results indicated that there is a wide variety of injuries caused by occupational footwear: from dermal injuries (e.g. calluses) and injuries to the nail apparatus to inflammatory pathologies such as plantar fasciitis or bursitis. In addition, inappropriate footwear can cause pain in the ankle and foot, knees, hips and lower back. Other results include the discomfort derived from the footwear itself. CONCLUSIONS: Inappropriate footwear can cause injuries to the foot and other related bone structures. Further studies are needed on the detection of foot injuries caused by occupational footwear and the levels of action at this level to improve the worker's health, the adaptability of the footwear to the wearer, and the worker's comfort and adherence to the footwear.


Assuntos
Traumatismos Ocupacionais , Sapatos , Humanos , Bursite/etiologia , Fasciíte Plantar/etiologia , Traumatismos do Pé/etiologia , Doenças Profissionais/etiologia , Traumatismos Ocupacionais/etiologia , Sapatos/efeitos adversos
3.
J Environ Radioact ; 270: 107314, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37866319

RESUMO

Conventional 210Pb-dating models use assumptions on sedimentary conditions that allow for analytical formulations. The novel χ-mapping models use numerical methods to generate and test a large number (∼106) of potential solvers. Empirical data (excess 210Pb vs. mass depth profile) serve to attract the solver that minimizes the χ function (the attractor), and it has been assumed that it also defines the most likely chronology. This work aims to test this assumption in a deep way. In synthetic and varved sediments, the performance of each solver can be quantified through a parameter ξa accounting for the deviation of the model and the true ages. This work studies the complex relationships between χ and ξa using the constant flux (χ-CF) and the constant sediment accumulation rate (CSAR) models, which operate in a parametric 3D space. The full mapping of the 3D χ function serves to find the absolute minimum, for the graphical representation of the complex topology of the attractors, which is model-specific, and for plotting clouds of chronological lines from solvers with varying χ values. The minimum value of ξa (the best chronology) is achieved for a wide range of χ values, including the region of the absolute minimum. In complex cases, tiny changes in χ can result in quite different chronologies. Alternative attractors that include a reference date and an objective function are studied. The results provide guidelines for strengthening the 210Pb-based chronologies.


Assuntos
Monitoramento de Radiação , Monitoramento de Radiação/métodos , Chumbo , Radioisótopos de Chumbo/análise , Sedimentos Geológicos , Monitoramento Ambiental/métodos
4.
Opt Express ; 31(18): 29452-29464, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710745

RESUMO

In this work, we develop experimentally a Fabry-Perot fiber optic interferometer applied to the measurement of autocorrelation of complex dynamic pulses generated by a figure-eight fiber laser. The principle is based in the superposition of multiple pulses, which requires two partially reflecting flat surfaces in parallel, resulting in a simple and compact autocorrelator design. The autocorrelation trace obtained exhibits a typical double-scaled structure for noise-like pulses (NLPs), with an ultrashort coherence spur on the order of 100 fs riding upon a broad pedestal of 120 ps. Finally, we show experimentally that the developed Fabry-Perot device is able to measure accurately the autocorrelation of NLPs, as confirmed by comparing the measurement with that of a conventional autocorrelator scheme based on a Michelson interferometer, with the additional advantages of a more compact setup and a much easier alignment procedure compared to the latter.

5.
J Environ Radioact ; 268-269: 107248, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37515861

RESUMO

The 210Pb-based method has been widely used for five decades to determine absolute ages in recent sediments on the centennial scale. Decoding a chronology from the empirical data set requires a series of assumptions that define a mathematical model of the sedimentary conditions. This work aims to provide a comprehensive review of the fundamentals of the existing family of models assuming a constant flux of excess 210Pb at the sediment surface, namely the CFCS, CRS, and PLUM models, and to present the novel χ-mapping versions of the CFCS and CF models. Their performance is assessed with a selected group of five cores from literature data, with varve chronologies or independent time marks. The PLUM model did not produce reliable chronologies in any of the cores studied. The CRS model is too sensitive to an accurate estimation of the total inventory. A weighted-fit and the χ-mapping versions of the CFCS model are prone to over-represent the younger regions of the core. The CFCS model with least squares fitting and the χ-CF models performed best under the most common sedimentary conditions, which involve temporal variability in the fluxes randomly distributed in the time line. A practical strategy is suggested to identify the occurrence of such sedimentary conditions through the combined use of a set of models, providing this way further strength to the 210Pb-dating.


Assuntos
Prunus domestica , Monitoramento de Radiação , Chumbo , Radioisótopos de Chumbo/análise , Sedimentos Geológicos , Monitoramento Ambiental/métodos
6.
J Environ Radioact ; 268-269: 107247, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37499335

RESUMO

The 210Pb-based method aims at determining the absolute age of recent sediments on the centennial scale. A family of models assumes that at the sediment-water interface the flux of unsupported 210Pb (210Pbexc), F, relates to its initial activity concentration, Ao, and the mass sedimentation rate, w, as: F=Aow. Additional specific assumptions that allow for analytical formulations of the models are: i) constant Ao (CIC), constant F (CF), and constant F with constant w (CFCS). A model with constant w (CSAR) was suggested for completeness but never used because of the lack of a suitable analytical formulation. The TERESA model assumes random and independent variability for Ao and w, described by normal distributions. It systematically generates a large number (∼105) of potential solutions, whose performance for fitting the empirical 210Pbexc profile is quantified through the χ-function. This work aims to adapt the above methodology to formulate the χ-mapping version of the CSAR model. The performance of the model is evaluated with a set of synthetic and real cores for which an independent chronology is available. CSAR is able to capture the mean sedimentation rate from the 210Pbexc data and provides reliable chronologies and paleorecords of Ao, useful for tracking past changes in sedimentary conditions. CSAR provides an interesting different perspective for researchers working with 210Pb-based dating of recent sediments.


Assuntos
Monitoramento de Radiação , Monitoramento de Radiação/métodos , Sedimentos Geológicos , Chumbo , Radioisótopos de Chumbo/análise , Água , Monitoramento Ambiental/métodos
7.
Immunol Lett ; 259: 9-20, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37225058

RESUMO

Plasma cells (PCs) are terminally differentiated antibody-secreting cells, derived from activated B-lymphocytes in response to either T-independent or T-dependent antigens. The plasma cell population is scarce in circulation in non-immunized individuals. It is established that neonates are incapable of mounting an efficient immune response due to the immaturity of the immune system. However, this disadvantage is well overcome through the antibodies neonates receive from breastmilk. This implies that neonates will be only protected against antigens the mother had previously encountered. Thus, the child might be potentially susceptible to new antigens. This issue prompted us to seek for the presence of PCs in non-immunized neonate mice. We found a PC population identified as CD138+/CD98+ cells since day one after birth. These PCs were positive for Ki67 and expressed Blimp-1, B220, and CD19, which suggests the populations are plasmablasts and PCs with heterogeneous phenotype. These PCs were also determined to secrete antibodies, although mainly isotype IgM. Altogether, the results indicated that neonate PCs can produce antibodies against antigens they encounter in the first weeks of life, most likely coming from food, colonizing microbiota, or the environment.


Assuntos
Linfócitos B , Plasmócitos , Animais , Camundongos , Anticorpos , Antígenos CD19 , Sistema Imunitário , Proteína-1 Reguladora de Fusão
8.
Open Biol ; 13(5): 230049, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37161288

RESUMO

Nutrient scarcity is a frequent adverse condition that organisms face during their development. This condition may lead to long-lasting effects on the metabolism and behaviour of adults due to developmental epigenetic modifications. Here, we show that reducing nutrient availability during larval development affects adult spontaneous activity and sleep behaviour, together with changes in gene expression and epigenetic marks in the mushroom bodies (MBs). We found that open chromatin regions map to 100 of 241 transcriptionally upregulated genes in the adult MBs, these new opening zones are preferentially located in regulatory zones such as promoter-TSS and introns. Importantly, opened chromatin at the Dopamine 1-like receptor 2 regulatory zones correlate with increased expression. In consequence, adult administration of a dopamine antagonist reverses increased spontaneous activity and diminished sleep time observed in response to early-life nutrient restriction. In comparison, reducing dop1R2 expression in MBs also ameliorates these effects, albeit to a lesser degree. These results lead to the conclusion that increased dopamine signalling in the MBs of flies reared in a poor nutritional environment underlies the behavioural changes observed due to this condition during development.


Assuntos
Dopamina , Drosophila , Animais , Drosophila/genética , Larva/genética , Dieta , Encéfalo , Cromatina/genética , Epigênese Genética , Nutrientes
9.
Rev Clin Esp (Barc) ; 223(4): 223-230, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36933696

RESUMO

INTRODUCTION AND OBJECTIVES: According to the recent European epidemiological studies, the degree of lipid control in patients with very high vascular risk is suboptimal. This study analyzes the epidemiological characteristics, cardiovascular risk factors, lipid profile, recurrence, and degree of achievement of long-term lipid targets, according to the ESC/EAS Guidelines, in a cohort of patients with acute coronary syndrome (ACS) in a real-world clinical practice setting. METHODS: This work is a retrospective cohort study of patients diagnosed with ACS admitted to the Coronary Unit of a tertiary hospital from January 1, 2012 to December 31, 2015 and followed-up on until March 2022. RESULTS: A total of 826 patients were studied. During the follow-up period, greater prescribing of combined lipid-lowering therapy was observed, mainly high- and moderate-intensity statins and ezetimibe. At 24 months after the ACS, 33.6% of living patients had LDL levels <70 mg/dl and 9.3% had LDL levels <55 mg/dl. At the end of the follow-up (101 [88-111] months), the corresponding figures were 54.5% and 21.1%. Some 22.1% of patients had a recurrent coronary event and only 24.6% achieved an LDL level <55 mg/dl. CONCLUSIONS: Achievement of the LDL targets recommended by the ESC/EAS guidelines is suboptimal in patients with ACS, both at two years and in the long-term (7-10 years), especially in patients with recurrent ACS.


Assuntos
Síndrome Coronariana Aguda , Anticolesterolemiantes , Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Síndrome Coronariana Aguda/tratamento farmacológico , Resultado do Tratamento , Estudos Retrospectivos , LDL-Colesterol , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico
10.
Environ Pollut ; 323: 121244, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36775133

RESUMO

The kinetics of the uptake of pollutants by solids in sediments interacts with transitional eddy diffusivity in the pore fluid, leading to different depth-distribution patterns. This work aims to gain insights into the still poorly understood behaviour in the marine environment of the anthropogenic 236U, a recently postulated tracer of water masses. It is hypothesized that the transition from mobile U(VI) to highly particle-reactive U(IV) in the anoxic zone of the sediment produces a subsurface deposition pattern. A novel numerical model for kinetic reactive transport in sediments, which merges diagenetic processes for transport and box models for the uptake, is used for concept demonstration. It is applied to synthetic environments with high eddy diffusivity to obtain the singular depth-distribution patterns of pulsed inputs of tracers that mimic the anthropogenic 239,240Pu, 137Cs, and 236U. While the first is retained in the upper cm, the second shows an exponential penetration pattern over few cm, and 236U is deposited with a Gaussian-like pattern centred below the transition to the anoxic zone. These patterns are then merged into a diagenetic model to compute the depth distribution at decadal or centennial scales of dissolved and particle-bound inputs of these radiotracers. It is successfully applied to a real case using literature data for a sediment core from the Esk Estuary, UK, affected by radioactive releases from the Sellafield nuclear reprocessing plant. This work provides insight into until now poorly understood field data and provides a novel view of broad implications in the study of the behaviour of pollutants in surficial aquatic sediments.


Assuntos
Poluentes Ambientais , Monitoramento de Radiação , Poluentes Radioativos da Água , Sedimentos Geológicos , Cinética , Estuários , Poluentes Radioativos da Água/análise , Reino Unido
11.
Rev Clin Esp (Barc) ; 223(2): 77-83, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36669741

RESUMO

INTRODUCTION AND OBJECTIVES: Retinal vein occlusion (RVO) and nonvalvular atrial fibrillation (NVAF) are associated with vascular risk factors (VRF) and aging. The aim of this study is to analyze differences in the prevalence of VRF, vascular events, glaucoma, and anticoagulant treatment in patients with NVAF and RVO compared to a control group of the general population from the same geographic area. METHODS: This is a prospective, single-center, case-control study. All patients diagnosed with RVO from December 2008 to March 2020 as well as a control group were included. Clinical, laboratory, electrocardiographic, and carotid ultrasound variables were analyzed. RESULTS: A total of 386 patients with RVO and 343 controls were studied. Patients with RVO and NVAF were older and more of them had hypertension, a history of vascular events, and carotid atheromatosis than subjects with RVO without NVAF. In patients with NVAF who were on anticoagulants, those who had RVO differed from the controls with NVAF in that they had a higher prevalence of glaucoma (32 vs. 5.3%; p<0.034), with no significant differences regarding age, VRF, vascular events, or type of anticoagulant therapy (acenocumarol or direct-acting oral anticoagulants). CONCLUSIONS: Patients with RVO and NVAF were older and had a higher prevalence of hypertension and carotid atheromatosis than subjects with RVO without NVAF. Patients with NVAF and RVO had higher prevalence of glaucoma than subjects with NVAF without RVO. In patients with NVAF, it is recommended to optimized VRF treatment and glaucoma control to prevent the development of RVO.


Assuntos
Fibrilação Atrial , Doenças das Artérias Carótidas , Glaucoma , Hipertensão , Oclusão da Veia Retiniana , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/tratamento farmacológico , Estudos de Casos e Controles , Estudos Prospectivos , Oclusão da Veia Retiniana/etiologia , Oclusão da Veia Retiniana/complicações , Anticoagulantes/uso terapêutico , Fatores de Risco , Hipertensão/epidemiologia , Doenças das Artérias Carótidas/induzido quimicamente , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/tratamento farmacológico , Glaucoma/epidemiologia , Glaucoma/induzido quimicamente , Glaucoma/complicações
14.
Mater Lett ; 311: 131554, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34963705

RESUMO

COVID-19 pandemic created a global shortage of medical protective equipment. Here, we considered ozone (O3) a disinfectant alternative due to its potent oxidative activity against biological macromolecules. The O3 decontamination assays were done using SARS-CoV-2 obtained from patients to produce artificial contamination of N95 masks and biosecurity gowns. The quantification of SARS-CoV-2 was performed before and after exposing the samples to different ozone gas concentrations for times between 5 and 30 min. Viral loads as a function of the O3 exposure time were estimated from the data obtained by the RT-PCR technique. The genetic material of the virus was no longer detected for any tested concentrations after 15 min of O3 exposure, which means a disinfection Concentration-Time above 144 ppm min. Vibrational spectroscopies were used to follow the modifications of the polymeric fibers after the O3 treatment. The results indicate that the N95 masks could be safely reused after decontamination with treatments of 15 min at the established O3 doses for a maximum of 6 cycles.

15.
Neth Heart J ; 30(6): 328-334, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34910278

RESUMO

INTRODUCTION: Sex disparities exist in coronary artery disease (CAD) in terms of risk profile, clinical management and outcome. It is unclear if differences are also present in coronary aneurysms, a rare variant of CAD. METHODS: Patients were selected from the international Coronary Artery Aneurysm Registry (CAAR; ClinicalTrials.gov: NCT02563626), and differences between groups were analysed according to sex. The CAAR database is a prospective multicentre registry of 1565 patients with coronary aneurysms (336 females). Kaplan-Meier method was used for event-free survival analysis for death, major adverse cardiac events (MACE: composite endpoint of death, heart failure and acute coronary syndrome) and bleeding. RESULTS: Female patients were older, were more often hypertensive and less frequently smoker. They were treated conservatively more often compared to male patients and received significantly less frequently aspirin (92% vs 88%, p = 0.002) or dual antiplatelet therapy (DAPT) (67% vs 58%, p = 0.001) at discharge. Median DAPT duration was also shorter (3 vs 9 months, p = 0.001). Kaplan-Meier analysis revealed no sex differences in death, MACE or bleeding during a median follow-up duration of 37 months, although male patients did experience acute coronary syndrome (ACS) more often during follow-up (15% vs 10%, p = 0.015). CONCLUSIONS: These CAAR findings showed a comparable high-risk cardiovascular risk profile for both sexes. Female patients were treated conservatively more often and received DAPT less often at discharge, with a shorter DAPT duration. ACS was more prevalent among male patients; however, overall clinical outcome was not different between male and female patients during follow-up.

16.
Opt Quantum Electron ; 53(5): 237, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33907348

RESUMO

An experimental study of the interaction between a Mylar® polymer film and a multimode fiber-optic is presented for the simultaneous fiber-optic detection of low-pressure and liquid levels. The junction between the polymer and optical fiber produces an interference spectrum with maximal visibility and free spectral range around 9 dB and 31 nm, respectively. Water pressure, which is controlled by the liquid level, stresses the polymer. As a result, the spectrum wavelength shifts to the blue region, achieving high sensitivities around 2.49 nm/kPa and 24.5 nm/m. The polymeric membrane was analyzed using a finite element model; according to the results, the polymer shows linear stress response. Furthermore, the membrane material is operated below the yielding point. Moreover, the finite analysis provides information about the stress effect over the thickness and the birefringence changes. This sensor exhibits a quadratic polynomial fitting with an adjusted R-squared of 0.9539. The proposed sensing setup offers a cost-effective alternative for liquid level and low-pressure detection.

17.
Astron Astrophys ; 6452021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33408420

RESUMO

CONTEXT: Yebes 40m radio telescope is the main and largest observing instrument at Yebes Observatory and it is devoted to Very Long Baseline Interferometry (VLBI) and single dish observations since 2010. It has been covering frequency bands between 2 GHz and 90 GHz in discontinuous and narrow windows in most of the cases, to match the current needs of the European VLBI Network (EVN) and the Global Millimeter VLBI Array (GMVA). AIMS: Nanocosmos project, a European Union funded synergy grant, opened the possibility to increase the instantaneous frequency coverage to observe many molecular transitions with single tunnings in single dish mode. This reduces the observing time and maximises the output from the telescope. METHODS: We present the technical specifications of the recently installed 31.5 - 50GHz (Q band) and 72 - 90.5 GHz (W band) receivers along with the main characteristics of the telescope at these frequency ranges. We have observed IRC+10216, CRL 2688 and CRL 618, which harbour a rich molecular chemistry, to demonstrate the capabilities of the new instrumentation for spectral observations in single dish mode. RESULTS: The results show the high sensitivity of the telescope in the Q band. The spectrum of IRC+10126 offers a signal to noise ratio never seen before for this source in this band. On the other hand, the spectrum normalised by the continuum flux towards CRL 618 in the W band demonstrates that the 40 m radio telescope produces comparable results to those from the IRAM 30 m radio telescope, although with a smaller sensitivity. The new receivers fulfil one of the main goals of Nanocosmos and open the possibility to study the spectrum of different astrophysical media with unprecedented sensitivity.

18.
Front Genet ; 12: 740641, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095996

RESUMO

Prostate Cancer (PC) is commonly known as one of the most frequent tumors among males. A significant problem of this tumor is that in early stages most of the cases course as indolent forms, so an active surveillance will anticipate the appearance of aggressive stages. One of the main strategies in medical and biomedical research is to find non-invasive biomarkers for improving monitoring and performing a more precise follow-up of diseases like PC. Here we report the relevant role of IGF2 and miR-93-5p as non-invasive biomarker for PC. This event could improve current medical strategies in PC.

19.
Mar Environ Res ; 161: 105135, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32942210

RESUMO

Environmental changes have been associated with natural climatic variability or human activity. Water resources management is, perhaps, the most drastic change observed in the coastal environment. However, external forcings such as the El Niño event have important implications in the global and regional hydrological balance. These environmental changes have an impact on the density and biomass of the ichthyofauna in the Terminos Lagoon (TL) for the past 30 years, presumably, associated with variations in the temperature and surface salinity of the sea. Therefore, in the present study, δ18O was quantified in otoliths of two important species due to their dominance: Stellifer lanceolatus and Eucinostomus gula, and to understand the environmental changes reflected in both species. The δ18O was analyzed in otoliths of these two species captured in 1998/1997, 2006/2007 and 2016/2017 and were compared with in situ temperature and salinity data. Sea surface temperature and salinity increased by 2 °C and 9, respectively, between 1997 and 2017. Stellifer lanceolatus δ18O values was in isotopic equilibrium with seawater calcite; while, E. gula is not in isotopic equilibrium. The δ18O of S. lanceolatus and E. gula varied significantly with the increase in salinity (R2 = 0.8987 and R2 = -0.2964) and not with the sea surface temperature. S. lanceolatus is an excellent bioindicator of changes in sea surface salinity in this region of the Gulf of Mexico.


Assuntos
Membrana dos Otólitos , Água do Mar , Animais , Golfo do México , Humanos , México , Salinidade
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