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1.
J Cosmet Dermatol ; 23(5): 1551-1559, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38284294

RESUMO

BACKGROUND: Androgenetic alopecia (AGA), also referred to as male or female pattern hair loss, is the commonest cause of chronic hair loss and affects up to 80% of men by the age of 70. Despite a high prevalence, there are few approved therapies, which show minimal efficacy. OBJECTIVES: This systematic review aims to evaluate the efficacy of platelet-rich plasma (PrP) in the treatment of AGA in male patients. METHODS: MEDLINE, EMBASE, Cochrane (CENTRAL), CINAHL, clinicaltrials.gov, Google Scholar and the Science Citation Index database were searched to identify eligible studies. All randomized controlled trials (RCTs) and prospective cohort studies related to PrP use in AGA were included. Primary outcomes included changes in hair density and hair count. Methodological quality was assessed using bias assessment tools. RESULTS: Eight RCTs and one cohort study were included in the review with a total of 291 participants. Six studies reported a statistically significant increase in hair density in the PrP group versus the control. Five studies reported a statistically significant increase in hair count with PrP. Seven studies showed moderate risk and two showed low risk of bias. CONCLUSION: In a methodologically robust review on the effectiveness of PrP on male AGA, PrP demonstrated some potential to be used therapeutically. However, the low quality of evidence, moderate risk of bias, and high heterogeneity of included studies limit inferences and call for more robust designs to investigate this further.


Assuntos
Alopecia , Plasma Rico em Plaquetas , Humanos , Masculino , Alopecia/terapia , Cabelo/crescimento & desenvolvimento , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
2.
J Mol Graph Model ; 126: 108637, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37801810

RESUMO

Amino acids are required to make protein. The deficiency of amino acids leads to a lack of sleep and mood. Among various amino acids, we conducted the adsorption studies of alanine and asparagine amino acids on a novel one-dimensional material, chair graphene nanotube. The stability of the chair graphene nanotube is ensured with the negative formation energy, which is -6.490 eV/atom. The energy band gap of bare chair graphene nanotube is 1.022 eV, which possesses a semiconductor nature. The stable chair graphene nanotube is used as adsorbing material for alanine and asparagine amino acids. Besides, alanine and asparagine are physisorbed on chair graphene nanotubes that are confirmed by the range of adsorption energy from -0.107 eV to -0.718 eV. Upon adsorption of amino acids, the charge transfer outcome shows that chair graphene nanotubes behave as donors of electrons to alanine and asparagine. Further, the changes in the band gap of the chair graphene nanotube are noticed from the results of band structure and PDOS spectrum. The changes in the electron density also reveal the changes in the electronic properties of the chair graphene nanotube owing to alanine and asparagine sorption. The proposed report portrays the adsorption attributes of alanine and asparagine amino acids on 1D chair graphene nanotubes.


Assuntos
Grafite , Nanotubos , Aminoácidos/química , Alanina/química , Asparagina , Grafite/química , Nanotubos/química
3.
J Mol Model ; 29(10): 309, 2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37688608

RESUMO

CONTEXT: N-Nitrosamine is one of the highly toxic carcinogenic compounds that are found almost in the entire environment. In the present work, novel penta-silicene (penta-Si) and penta-silicane (penta-HSi) are utilised to sense the N-nitrosamine in the air environment. Initially, structural firmness of penta-Si and penta-HSi is confirmed using cohesive energy. Subsequently, the electronic properties of penta-Si and penta-HSi are discussed with the aid of electronic band structure and projected density of states (PDOS) maps. The calculated band gap of penta-Si and penta-HSi is 0.251 eV and 3.117 eV, correspondingly. Mainly, the adsorption property of N-nitrosamine on the penta-Si and penta-HSi is studied based on adsorption energy, Mulliken population analysis along with relative energy gap changes. The computed adsorption energy range is in physisorption (- 0.101 to - 0.619 eV), which recommends that the proposed penta-Si and penta-HSi can be employed as a promising sensor to detect the N-nitrosamine in the air environment. METHODS: The structural, electronic and adsorption behaviour of N-nitrosamine on penta-Si and penta-HSi are studied based on the density functional theory (DFT) approach. The hybrid generalized gradient approximation (GGA) with Becke's three-parameter (B3) + Lee-Yang-Parr (LYP) exchange correlation functional is used to optimise the base material. All calculations in the present work are carried out in Quantum-ATK-Atomistic Simulation Software.

4.
J Mol Graph Model ; 122: 108473, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37060642

RESUMO

The recent advancement in group VA monolayer and few-layer materials leads to fascinating applications. In this mini-review, we present the state-of-the-art in the synthesis of antimonene, its properties and various applications. Besides, the electronic properties of antimonene depend on its allotropes. Furthermore, we studied the electronic properties of δ, ε, and twisted-θ antimonene nanosheets, nanoribbons, and nanoring, and the results are reported. Moreover, the structural stability and electronic properties of antimonene is influenced by its allotrope and nanostructure. The report will give insights into the synthesis, properties, applications, and future outlook of antimonene.


Assuntos
Eletrônica , Nanoestruturas
5.
J Mol Graph Model ; 121: 108449, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36965229

RESUMO

In this research work, we employed a tricycle graphane nanosheet as a chemical sensor to monitor the toxic hydrocarbon molecules, namely propylene, and 1,3-butadiene, which are emitted from automobile industries. At first, the structural stability and dynamical permanency of tricycle graphane is ascertained based on cohesive energy and phonon-band-spectrum. Sequentially, the electronic properties of tricycle graphane are conferred with the results of the projected density of states spectrum and band structure. The computed band gap of tricycle graphane is 5.53 eV. Chiefly, the adsorption behaviour of target propylene and 1, 3-butadiene on tricycle graphane is explored by determining adsorption energy, relative band gap variation, and Mulliken population analysis. Furthermore, the range of adsorption energy magnitudes (-0.16 eV to -1.03 eV) demonstrates that the target hydrocarbon molecules are physically adsorbed on tricycle graphane material. The overall outcome endorses that the tricycle graphane can be utilised as a prominent sensor to sense the hydrocarbon molecules released from automobiles and monitor air pollutants.

6.
J Mol Graph Model ; 119: 108395, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36549225

RESUMO

In the present work, we deployed a novel orthorhombic germanane nanosheet (ortho-GeNS) as a sensing material to detect camphene and eucalyptol molecules, the indoor air pollutants in the ambient environment. In the beginning, the structural and dynamical permanency of ortho-GeNS is confirmed with cohesive energy (-4.164eV/atom) and phonon-band maps. Successively, the electronic features of ortho-GeNS are conferred using band structure along with the projected density of states maps. The energy gap of ortho-GeNS at the hybrid GGA/B3LYP level of theory is computed to be 3.948 eV. Mainly, the adsorption properties of terpinene molecules, namely camphene and eucalyptol on ortho-GeNS are investigated via ascertaining adsorption energy, Mulliken population analysis, and relative band gap variations. Besides, the scope of adsorption energy values (-0.405eVto-0.669eV) exemplifies that the target molecules are physisorbed on ortho-GeNS. Overall results suggested that the ortho-GeNS can be deployed as a worthy chemiresistive sensor to sense indoor air pollutants for monitoring indoor air quality.


Assuntos
Poluentes Atmosféricos , Eucaliptol , Adsorção
7.
J Mol Graph Model ; 115: 108233, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35661590

RESUMO

The structural stability of novel ζ-arsenene nanotubes (ζ-AsNT) is studied based on the density functional theory framework and is used as a base material for the detection of trichloroethylene and tetrachloroethylene vapours. The formation energy of ζ-AsNT is found to be -4.321 eV/atom and the energy band gap is 0.304 eV. Besides, the changes in the electronic properties of ζ-AsNT are explored with regard to the projected density of states, charge transfer, and electron density difference. The bandgap energy decreases for hollow site orientation to 0.205 and 0.204 eV for trichloroethylene and tetrachloroethylene vapours and increases for the valley and top site orientations. The adsorption energies were maximum for the valley site orientation of target molecules onto ζ-AsNT (01.165 and -1.513 eV for trichloroethylene and tetrachloroethylene, respectively). Moreover, the target vapours trichloroethylene and tetrachloroethylene are physisorbed on ζ-AsNT enabling the recycling of base substrate for continuous operation. The average energy gap changes vary from 18 to 32.9% depending on adsorption sites. The variation in the average energy gap owing to adsorption of trichloroethylene and tetrachloroethylene indicates the chemo-sensing nature of ζ-AsNT. The current report lays the inroads in the development of a new sensing element for the detection of chloroethylene molecules.


Assuntos
Nanotubos , Tetracloroetileno , Tricloroetileno , Adsorção , Gases , Tetracloroetileno/análise , Tricloroetileno/análise
8.
J Mol Graph Model ; 109: 108034, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34555724

RESUMO

2D (two-dimensional) materials are emerging in today's world. Among the 2D materials, arsenene sheets are prominently used as chemical and biosensors. In the present work, the twisted bilayer arsenene sheets (TB-AsNS) are used to adsorb toluene and M-xylene vapours. Moreover, the band gap of pristine TB-AsNS is calculated to be 0.437 eV. Besides, the surface adsorption of toluene and M-xylene vapours modify the electronic properties of TB-AsNS noticed from the band structure, density of states, and electron density difference diagrams. The surface assimilation of target toluene and M-xylene on TB-AsNS falls in the physisorption regime facilitating the adsorption and desorption of molecules. Also, the charge transfer analysis infers that TB-AsNS acts as acceptor and target molecules play as donors. The findings support that TB-AsNS can be used as a sensing medium towards M-xylene and toluene.


Assuntos
Tolueno , Xilenos , Adsorção , Gases
9.
J Mol Graph Model ; 107: 107971, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34217025

RESUMO

We ascertained the structural stability of zipper phosphorene nanosheet (zP-NS) and studied the adsorption behaviour of toxic aldehyde compounds including formaldehyde (FD) and acetaldehyde (AD) on zP-NS based on first-principles calculation. Considerably, zP-NS reveal a semiconducting character with band gap of 1.35 eV. Especially, four distinct favourable adsorption positions including bridge-, hollow-, top- and valley-site of FD and AD vapours on zP-NS were investigated. Furthermore, the calculated binding-energy of prominent adsorption sites are observed to be in the scope of -0.143 eV to -0.411 eV advocating physisorption nature of the interaction of chief aldehydes on zP-NS. The overall outcomes recommend that zP-NS can be persuasively utilised as a chemical sensor for monitoring FD and AD molecules in indoor air environment.


Assuntos
Acetaldeído , Formaldeído , Adsorção , Aldeídos , Gases
10.
J Mol Graph Model ; 108: 107988, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34325354

RESUMO

We ascertained the structural firmness of ß-antimonene nanotube and studied the adsorption behaviour of sulfadimethoxine (SM) and tetracycline (TC) molecules on the base substrate using density functional theory (DFT) with B86LYP-D3 level of theory. Significantly, ß-antimonene nanotube displays a semiconducting character with an energy band-gap of 0.263 eV. The three dissimilar preferential adsorption sites namely, bride-, hollow-, tube-inner site of SM and TC molecules on ß-antimonene nanotube were investigated using average band gap changes, Bader charge transfer along with adsorption energy. Further, the calculated adsorption energy for preferential adsorption sites is noticed to be in the scope of -0.813 eV to -3.752 eV signifying to physisorption and chemisorption form of interaction on ß-antimonene nanotube. The inclusive outcome recommends that ß-antimonene nanotube can be deployed as a chemi-resistive sensor to sense and remove SM and TC molecules from the contaminated aqueous medium.


Assuntos
Nanotubos , Sulfadimetoxina , Adsorção , Tetraciclinas
11.
J Mol Graph Model ; 105: 107895, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33752097

RESUMO

We investigated the structural stability of ß-tellurene nanoribbon (ß-TeNR) and explored the adsorption behaviour of glycine, acetate, and methylamine malodorous molecules on ß-TeNR based on ab-initio calculations. Besides, ß-TeNR exhibits semiconducting behaviour with a direct energy gap (Eg) of 1.657 eV. In the beginning, the dynamical solidity and geometrical firmness were confirmed with regard to the phonon band spectrum and negative cohesive energy (-3.406 eV/atom), respectively. With the support of band structure and PDOS (projected-density of states), the electronic characteristics of ß-TeNR are explored. Provocatively, two dissimilar superior adsorption sites (top &hollow-sites) of chief malodorous on ß-TeNR were demonstrated with regard to the average band gap variation (Ega), Bader charge transfer (Q), and binding energy (EB). The calculated EB of preferential interaction sites is found to be in the scope of -0.190 to -1.751 eV referring to mixed physisorption and chemisorption type of interaction upon ß-TeNR. The outcomes recommend that ß-TeNR can be positively utilised as a chemi-resistor to sense the glycine, acetate, and methylamine molecules in an unpleasant atmosphere.


Assuntos
Nanotubos de Carbono , Acetatos , Adsorção , Glicina , Metilaminas
12.
J Mol Graph Model ; 103: 107827, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33370614

RESUMO

The electronic attributes and energetics of ε-arsenene nanosheet (ε-As) are explored with regard to the density functional theory basis. Initially, based on formation energy (-3.715 eV/atom), we ensured the structural firmness of ε-As. The ε-As is used as a base substrate to adsorb nucleobases viz., adenine (A), guanine (G), thymine (T), cytosine (C) & uracil (U). The surface adsorption of nucleobases on ε-As is analysed based on band structure, the density of states, adsorption energy, energy gap variation & charge transfer. Besides, we observed the exothermic nature of binding energy (ranging from -0.453 eV to -0.819 eV) upon nucleobase adsorption on ε-As. Also, the energy gap variation & charge transfer takes place owing to adsorption of nucleobases on the ε-As sheet. The present report reveals the adsorption of nucleobases on ε-arsenene nanosheet.


Assuntos
Citosina , Timina , Adenina , Adsorção , Guanina
13.
J Conserv Dent ; 24(5): 485-490, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35399765

RESUMO

Background: The antibacterial activity of restorative material and the amount of fluoride released are interlinked. Hence, these are the two foremost properties to be studied. Aim: This study aimed to evaluate and compare the amount and pattern of fluoride release from Type IX GIC (GC HS posterior), nanoionomer (Ketac N100), and alkasite (Cention N), and the antibacterial activity against Streptococcus mutans at 24 and 48 h. Settings and Design: This in vitro study was carried out in laboratory settings with six samples of each group for fluoride release using an ion-chromatography (IC) machine and five samples of each group for antibacterial activity using agar plates. Materials and Methodology: Samples of each group, Group I - Type IX GIC, Group II - nanoionomer, and Group III -alkasite, were prepared, immersed in 2 ml of artificial saliva, and fluoride release recorded using IC after 1, 7, 14, and 28 days intervals. The antibacterial activity against S. mutans was evaluated by placing samples of each group in the agar plates and measuring the diameter of zones of inhibition after 24 and 48 h. Statistical Analysis: One-way ANOVA test to check to mean differences between the groups and Tukey's honestly significant difference post hoc test for multiple intergroup comparisons (P = 0.05). Results: The Type IX GIC showed the highest fluoride release after day1. However, nanoionomer showed the maximum fluoride release for the remaining days. The least amount of fluoride released was from the alkasite throughout the study. The antibacterial activity of nanoionomer was the highest, followed by Type IX GIC and alkasite at both 24 and 48 h. Conclusions: Nanoionomer showed the highest fluoride release and antibacterial activity.

14.
J Mol Graph Model ; 100: 107706, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32858456

RESUMO

The green phosphorene (GP) nanosheet, one of the allotropes of layered phosphorene is employed to detect the existence of tear gas molecules. The tear gas molecules such as 1-bromo-2-butanone, bromoacetone, and bromobenzyl cyanide are examined with the service of the ATK-VNL package by employing density functional theory (DFT) method. The geometrical stability of the chief component is affirmed with the support of formation energy and electronic fingerprints of GP nanosheet like electron density, band structure, and projected density of states (PDOS) spectrum are estimated. In this research work, using DFT technique, for the first time, surface adsorption characteristics of the target molecules on GP nanosheet are explored with the assistance of adsorption energy, average energy gap variation, and Bader charge transfer, which further suggest the deployment of GP in sensing the presence of tear gas molecules.


Assuntos
Cianetos , Gases Lacrimogênios , Adsorção
15.
J Mol Graph Model ; 100: 107653, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32763794

RESUMO

The chemo sensing features of red tricycle arsenene nanosheet (RTANS), a monolayer obtained from allotropes of arsenic is employed in sensing the hazardous vapor nitroglycerin (NG) based on the first-principles investigation. The computations are carried out with the ATK-VNL package. The stability of the RTANS is validated by its formation energy, which is calculated as -4.171 eV/atom. The adsorption energy, Bader charge transfer, energy gap, and its variation after adsorption are the essential parameters that hold up the discussion on RTANS base material as an efficient chemical sensor. Moreover, the target vapor NG is physisorbed on RTANS. Besides, all the essential parameters have been investigated for the interaction of NG on RTANS. The comprehensive study reveals that RTANS can be used as a chemical sensor for the detection of nitroglycerin vapors.


Assuntos
Arsênio , Nitroglicerina , Adsorção , Gases
16.
J Mol Graph Model ; 97: 107566, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32088561

RESUMO

We report the electronic properties of black phosphorene nanoring (BPN) and adsorption behavior of chronic kidney disease biomarker vapors on BPN. The designed BPN is stable, which is ensured by the formation energy with a value of -3.857eV/atom. The band gap of BPN is recorded as 0.716eV showing the semiconductor property. The prominent kidney disease biomarker vapors, namely isoprene, pentanal, hexanal, heptanal are allowed to interact on BPN and studied based on adsorption property on BPN. Based on charge transfer, energy band gap variation and adsorption energy, we studied the adsorption behavior of BPN towards kidney disease biomarkers. Our findings show that BPN can be used to detect the presence of kidney biomarkers.


Assuntos
Gases , Adsorção , Biomarcadores , Humanos , Rim
17.
J Mol Graph Model ; 95: 107505, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31835076

RESUMO

The interrelation of toxic vapors ethylene dichloride (EDC) and ethylene dibromide (EDB) with the sensory base material blue phosphorene nanosheet (BLPNS) is studied using ab-initio method. The formational stability of BLPNS is ensured by the negative value of formation energy. Prior to the adsorption studies, we calculated the formation energy of BLPNS to ensure its stability, which is calculated to be -5.194eV/atom and found stable. The main motive behind the present work is to detect these toxic vapors using BLPNS. The intercommunication between the targeted vapors and the base material has been analyzed using the aid of adsorption energy, Bader charge transfer, energy band gap, and variation of band gap along with energy bands and DOS spectrum. The energy gap of isolated BLPNS is observed to be 1.621eV. However, the adsorption of EDC and EDB modulates the energy gap of BLPNS. The nature of assimilation is noticed to be of physisorption, which facilitates desorption of EDC and EDB molecules much easier. The successful outcome of the present research validates that BLPNS can be deployed as a prominent sensor for detection of EDC and EDB effectively.


Assuntos
Dicloretos de Etileno , Gases , Adsorção
18.
J Med Syst ; 43(10): 307, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31420756

RESUMO

The image restoration has emerged as a very vital investigation technique in the domain of the image processing. The underlying motive behind the image restoration is devoted to the augmentation of the perceived visual impact of image so as to make it almost identical to the original image. A host of exploration approaches are now in vogues which are intended to steer clear of the noise, thereby regaining the images with original quality. In our earlier research, two distinct noise elimination methods like the (OGHP) and SURE shrinkage were effectively employed for the purpose of denoising, though the relative PSNR and SSIM efficiencies did not come up to the desired level. In the innovative approach envisaged in the document, at the outset, the noise is included by means of two processes like the salt and pepper and impulse noise. Subsequently, the pre-processing methods are performed with the able assistance of two novel filters such as the adaptive median filter and adaptive fuzzy switching. Thereafter, the preprocessed image is furnished to the succeeding function of noise elimination like the (OGHP) and SURE shrinkage. In the course of the OGHP noise elimination technique, the GHP constraints are optimized by employing the Cuckoo Search Algorithm. Thereafter, the noise-eliminated image is effectively estimated with the help of the Discrete Wavelet Transform (DWT). The consequential noiseless images are subjected to the image restoration procedure by efficiently employing the AGA approach. The cheering performance outcomes chant the success stories of the novel image restoration method, highlighting its superlative efficiency. Moreover, the efficacy of the innovative approach is assessed by means of a set of noise-polluted images and contrasted with the modern noiseless image restoration technique.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Humanos , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído , Análise de Ondaletas
19.
J Mol Graph Model ; 92: 65-73, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31330439

RESUMO

Bis(2-chloroethyl)ethylamine (HN-1) and Bis(2-chloroethyl)methylamine (HN-2) are two classifications under the blistering agents, which are taken as target nitrogen mustard gas in the current research. α-arsenene nanosheets in its puckered configuration, are employed as a prime material to detect the above mentioned gas molecules. The chemo-sensing nature of the base material towards the target gas is ascertained with the assistance of electronic and surface assimilating attributes with the help of density functional theory technique. Initially, the geometric firmness of the base material is ensured with formation energy, which was computed to be -4.262 eV/atom, and we studied the electronic properties like the density of states spectrum, band structure, and electron density. Furthermore, surface assimilating attributes like Bader charge transfer, adsorption energy, average energy gap variation are estimated at atomistic levels using ATK-VNL package. The adsorption of nitrogen mustard gas molecules on α-arsenene nanosheets shows physisorption type of binding. The average energy gap variation of α-arsenene nanosheets upon adsorption of nitrogen mustard gas molecules ranges from 1.33 to 4.1%. Hence, the results suggest that α-arsenene nanosheets can be used as a chemical nanosensor for nitrogen mustard gas.


Assuntos
Substâncias para a Guerra Química/química , Gás de Mostarda/química , Nanoestruturas/química , Nitrogênio/química , Adsorção , Nanoestruturas/ultraestrutura , Análise Espectral
20.
J Mol Graph Model ; 91: 22-29, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31129554

RESUMO

We systematically investigated the adsorption characteristics of chronic obstructive pulmonary disease (COPD) biomarker volatiles on violet phosphorene with density functional theory approach. The formation energy of violet phosphorene indicates its stable structure. The electronic properties of violet phosphorene credit that it is a suitable material for biosensors. We explored the adsorption mechanism of hexanal and nonanal molecules based on electron density variation, the density of states (DOS) spectrum, band structure analysis of violet phosphorene. The results of adsorption energy, charge transfer also strengthen that COPD volatile organic compounds can be adsorbed on violet phosphorene. The proposed report strongly values that violet phosphorene as a prominent candidate to identify the biomarkers in COPD patients from the exhaled breath.


Assuntos
Biomarcadores/análise , Nanoestruturas/química , Fósforo/química , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Adsorção , Aldeídos/química , Elétrons , Conformação Molecular , Termodinâmica , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Volatilização
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