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1.
Forensic Sci Int ; 335: 111281, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35429777

RESUMO

We discuss how different accelerator-based techniques can be employed synergistically as a powerful analytical tool for forensic studies of foodstuff. Brazilian and Jamaican coffees were chosen as a showcase due to its popularity and potential risk of adulteration and/or falsification. Comprehensive characterization of major and trace elements, age since production and compound contents were achieved using different techniques, including PIXE (Particle-Induced X-ray Emission), FTIR (Fourier Transform Infrared), and AMS-14C (Accelerator Mass Spectrometry - Radiocarbon Analysis). While PIXE provides information on the elements present in the samples, FTIR probes the types of compounds through their vibrational spectra. Finally, AMS-14C is capable of dating organic samples regarding their harvesting time. Five different laboratories from research institutions around the world took part in the experiments. The integration of the results obtained with different techniques provided multifaceted perspectives on the coffee under study, thus allowing a direct assessment of the material for forensic purposes such as authentication, determination of provenance, and combat counterfeiting.


Assuntos
Café , Oligoelementos , Brasil , Contaminação de Medicamentos , Espectrometria de Massas/métodos
2.
Br Poult Sci ; 59(2): 245-249, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29235892

RESUMO

1. The effects of changes in technical efficiency on the increase of broiler production are presented for the period 1994-2013 based on the panel data from seven farms located in southern and central Poland. A total of 766 cycles were analysed. 2. The Cobb-Douglas production function was used to assess the changes of output elasticities as well as technical changes in broiler production, for 5-year sub-periods separately. 3. Technical indices of broiler production significantly improved between years 1994-2013: feed conversion ratio decreased from 2.50 kg/kg to 1.78 kg/kg, mortality rate from 8.8% to 4.0% and daily weight gain increased from 37.1 g/d to 58.7 g/d, respectively. 4. Before accession to the EU, there was a substantial increase of fixed capital connected with modernisation of buildings and equipment. In the period 1994-2013, inputs of fixed capital per kilogram of livestock increased by 72% and at the same time the input of labour decreased by 56%. 5. Technical changes in years 1994-1998 contributed to a rapid production increase at a rate of 4.6% annually and only by up to 0.7% annually during 2009-2013. The slowdown of production rate increase after 2009 was partially caused by decreasing the stocking density.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas , Criação de Animais Domésticos/tendências , Animais , Polônia , Aumento de Peso
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 171: 280-286, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27541800

RESUMO

Lactose and saccharose have the same molecular formula; however, the arrangement of their atoms is different. A major difference between lactose and saccharose with regard to digestion and processing is that it is not uncommon for individuals to be lactose intolerant (around two thirds of the population has a limited ability to digest lactose after infancy), but it is rather unlikely to be saccharose intolerant. The pharmaceutical industry uses lactose and saccharose as inactive ingredients of drugs to help form tablets because of their excellent compressibility properties. Some patients with severe lactose intolerance may experience symptoms of many allergic reactions after taking medicine that contains this substance. People who are specifically "allergic" to lactose (not just lactose intolerant) should not use tablets containing this ingredient. Fourier Transform Infrared (FTIR) spectroscopy has a unique chemical fingerprinting capability and plays a significant important role in the identification and characterization of analyzed samples and hence has been widely used in pharmaceutical science. However, a typical FTIR spectrum collected from tablets contains a myriad of valuable information hidden in a family of tiny peaks. Powerful multivariate spectral data processing can transform FTIR spectroscopy into an ideal tool for high volume, rapid screening and characterization of even minor tablet components. In this paper a method for distinction between FTIR spectra collected for tablets with or without lactose is presented. The results seem to indicate that the success of identifying one component in FTIR spectra collected for pharmaceutical composition (that is tablet) is largely dependent on the choice of the chemometric technique applied.


Assuntos
Lactose/análise , Preparações Farmacêuticas/química , Análise por Conglomerados , Furagina/química , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier , Sacarose/análise
4.
Obes Rev ; 18(2): 214-226, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27860169

RESUMO

Environmental, or 'choice-architecture', interventions aim to change behaviour by changing properties/contents of the environment and are commonly used in the workplace to promote healthy behaviours in employees. The present review aimed to evaluate and synthesize the evidence surrounding the effectiveness of environmental interventions targeting eating behaviour in the workplace. A systematic search identified 8157 articles, of which 22 were included in the current review. All included studies were coded according to risk of bias and reporting quality and were classified according to the emergent typology of choice-architecture interventions. More than half of included studies (13/22) reported significant changes in primary measures of eating behaviour (increased fruit/veg consumption, increased sales of healthy options and reduction in calories purchased). However, only one study produced a small significant improvement in weight/body mass index. Many studies had a high or unknown risk of bias; reporting of interventions was suboptimal; and the only trial to measure compensatory behaviours found that intervention participants who ate less during the intervention ate more out with the workplace later in the day. Hence, we conclude that more rigorous, well-reported studies that account for compensatory behaviours are needed to fully understand the impact of environmental interventions on diet and importantly on weight/body mass index outcomes.


Assuntos
Dieta Saudável , Comportamento Alimentar , Comportamentos Relacionados com a Saúde , Promoção da Saúde , Saúde Ocupacional , Frutas , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Verduras , Local de Trabalho
5.
Analyst ; 140(7): 2156-63, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25574521

RESUMO

The pituitary gland is a small but vital organ in the human body. It is located at the base of the brain and is often described as the master gland due to its multiple functions. The pituitary gland secretes and stores hormones, such as the thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), growth hormone (hGH), prolactin, gonadotropins, and luteinizing hormones, as well as the antidiuretic hormone (ADH). A proper diagnosis of pituitary disorders is of utmost importance as this organ participates in regulating a variety of body functions. Typical histopathological analysis provides much valuable information, but it gives no insight into the biochemical background of the changes that occur within the gland. One approach that could be used to evaluate the biochemistry of tissue sections obtained from pituitary disorders is Fourier Transform Infra-Red (FTIR) spectromicroscopy. In order to collect diagnostically valuable information large areas of tissue must be investigated. This work focuses on obtaining a unique and representative FTIR spectrum characteristic of one type of cell architecture within a sample. The idea presented is based on using hierarchical cluster analysis (HCA) for data evaluation to search for uniform patterns within samples from the perspective of FTIR spectra. The results obtained demonstrate that FTIR spectromicroscopy, combined with proper statistical evaluation, can be treated as a complementary method for histopathological analysis and ipso facto can increase the sensitivity and specificity for detecting various disorders not only for the pituitary gland, but also for other human tissues.


Assuntos
Hipófise/citologia , Espectroscopia de Infravermelho com Transformada de Fourier , Análise por Conglomerados , Humanos , Imagem Óptica , Hipófise/química
6.
Anal Bioanal Chem ; 406(17): 4173-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24752694

RESUMO

Fingerprint evidence offers great value to criminal investigations since it is an internationally recognized and established means of human identification. With recent advances in modern technology, scientists have started analyzing not only the ridge patterns of fingerprints but also substances which can be found within them. The aim of this work was to determine whether Fourier transform infrared (FTIR) spectromicroscopy could be used to detect contamination in a fingerprint which was dusted with powder (a technique already recognized as an effective and reliable method for developing latent fingerprints) and subsequently lifted off with adhesive tape. Explosive materials (pentaerythritol tetranitrate, C-4, TNT) and noncontrolled substances (sugar, aspirin) were used to prepare contaminated fingerprints on various substrates. Freshly deposited fingermarks with powders which were lifted off with adhesive tapes (provided by Singapore Police Force) were analyzed using a Bruker Hyperion 2000 microscope at the ISMI beamline (Singapore Synchrotron Light Source) with an attenuated total reflection objective. FTIR spectroscopy is a nondestructive technique which requires almost no sample preparation. Further, the fingerprint under analysis remains in pristine condition, allowing subsequent analysis if necessary. All analyzed substances were successfully distinguished using their FTIR spectra in powdered and lifted fingerprints. This method has the potential to significantly impact forensic science by greatly enhancing the information that can be obtained from the study of fingerprints.

7.
Analyst ; 137(15): 3459-65, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22693711

RESUMO

Synchrotron radiation-based Fourier transform infra-red (SR-FTIR) micro-imaging has been developed as a rapid, direct and non-destructive technique. This method, taking advantage of the high brightness and small effective source size of synchrotron light, is capable of exploring the molecular chemistry within the microstructures of microscopic particles without their destruction at high spatial resolutions. This is in contrast to traditional "wet" chemical methods, which, during processing for analysis, often caused destruction of the original samples. In the present study, we demonstrate the potential of SR-FTIR micro-imaging as an effective way to accurately identify microscopic particles deposited within latent fingerprints. These particles are present from residual amounts of materials left on a person's fingers after handling such materials. Fingerprints contaminated with various types of powders, creams, medications and high explosive materials (3-nitrooxy-2,2-bis(nitrooxymethyl)propyl nitrate (PETN), 1,3,5-trinitro-1,3,5-triazinane (RDX), 2-methyl-1,3,5-trinitrobenzene (TNT)) deposited on various - daily used - substrates have been analysed herein without any further sample preparation. A non-destructive method for the transfer of contaminated fingerprints from hard-to-reach areas of the substrates to the place of analysis is also presented. This method could have a significant impact on forensic science and could dramatically enhance the amount of information that can be obtained from the study of fingerprints.


Assuntos
Aspirina/análise , Dermatoglifia , Substâncias Explosivas/análise , Pós/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Síncrotrons , Carboidratos/análise , Humanos , Tamanho da Partícula , Triazinas/análise , Trinitrotolueno/análise
8.
J Biol Inorg Chem ; 16(8): 1187-96, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21706339

RESUMO

The prostate gland is the most common site of neoplastic disorders in men. The pathogenesis of inflammatory cells, prostatic intraepithelial neoplasia (PIN) lesions, and prostate cancer is still under investigation. Inflammatory cells by producing free radicals are considered as major and universal contributors to cancerogenesis. PIN is regarded as a precursor lesion to prostate cancer or a marker signaling the vulnerability of the epithelium to neoplastic transformation [1]. Differentiation markers that are frequently changed in early invasive carcinoma are also changed in PIN lesions. In this study, prostate tissue samples obtained during surgical operation and classified as various disease states (inflammation, PIN lesions, and cancer) were examined. The samples were measured by means of microbeam synchrotron-radiation-induced X-ray emission (micro-SRIXE). Special attention was paid to examine the relationship between the earlier-mentioned disorders and changes in relative concentrations of S, K, Ca, Fe, Cu, and Zn. Applying the image-processing program ImageJ enabled us to select the areas of interest from two-dimensional maps of various prostate samples according to the histopathologist's evaluation. Detailed analysis of micro-SRIXE spectra based on multivariate methods shows significant differences between elemental concentrations in inflammatory cells, PIN lesions, and cancerous tissues, which confirms that this method can be used to distinguish various pathological states in prostate tissues. Information obtained in this way may provide better understanding of the biochemistry of unhealthy prostate tissues, thus opening the way to find new medicines/treatments to prevent or slow down some harmful intracellular processes.


Assuntos
Próstata/química , Neoplasia Prostática Intraepitelial/química , Neoplasias da Próstata/química , Espectrometria por Raios X/métodos , Oligoelementos/análise , Idoso , Humanos , Inflamação/metabolismo , Inflamação/patologia , Masculino , Análise Multivariada , Próstata/patologia , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/patologia , Síncrotrons
9.
J Biol Inorg Chem ; 15(7): 1147-55, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20499115

RESUMO

The causes of prostate cancer are still obscure but some evidence indicates that there is a close connection between several trace elements and processes which may lead to malignant cells. In our study the microbeam synchrotron radiation X-ray fluorescence emission (micro-SRIXE) technique was applied for quantitative analysis of selected elements. For the first time, we correlate the concentrations of Mn, Fe, Cu, and Zn with the clinical stage of the prostate cancer at the time of operation (described by Gleason grade). Serial sections of prostate tissues were collected from patients undergoing radical prostatectomy. One section, stained with hematoxylin and eosin, was prepared for histopathological analysis; a second, adjacent unstained section was used in micro-SRIXE experiments. All experiments were performed at beamline L at HASYLAB, DESY, Germany. Our results seem to be valuable in light of the determination of the changes in the concentrations of trace elements as a potential diagnostic marker and their etiological involvement in the different stages of prostate diseases.


Assuntos
Próstata/química , Neoplasias da Próstata/química , Neoplasias da Próstata/patologia , Oligoelementos/análise , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Próstata/patologia , Espectrometria por Raios X/métodos , Síncrotrons
10.
Anal Chem ; 82(7): 3038-44, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20218700

RESUMO

Fourier transform-infrared (FT-IR) spectroscopy has gained considerable attention among the forensic scientists because it shows high sensitivity and selectivity and offers near real time detection of analyzed samples. However, the amount of obtained information due to complexity of the measured spectra forces the use of additional data processing. Application of the multivariate statistical techniques for the analysis of the FT-IR data seems to be necessary in order to enable feature extraction, proper evaluation, and identification of obtained spectra. In this article, an attempt to develop a feasible procedure for characterization of spectroscopic signatures of the explosive materials in the remnants after explosion has been made. All spectra were derived after analysis of samples from debris after especially prepared and performed blasts with the use of three various highly explosive materials: C-4, 2,4,6-trinitrotoluene (TNT), and pentaerythritol tetranitrate (PETN). Two well-known multivariate statistical methods, hierarchical cluster analysis (HCA) and principal component analysis (PCA), were tested in order to classify the samples into separate classes using a broad wavelength data range (4000-600 cm(-1)) on collected spectra sets. After many trials it seems that PCA is the best choice for the mentioned earlier tasks. It was found that only three principal components carry over 99.6% of variance within the sample set. The results show that FT-IR spectroscopy in combination with multivariate methods is well-suited for identification and differentiation purposes even in quite large data sets, and for that reason forensic laboratories could employ these methods for rapid screening analysis.

11.
Neuroradiol J ; 21(2): 219-27, 2008 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-24256830

RESUMO

The aim of this study was the application of magnetic resonance diffusion anisotropy imaging (MR DAI) for assessment of spinal cord compression (SCC) and injury (SCI) in rats depending on the time course from the moment of injury. Twenty rats were used, divided into three groups (five with no surgical operation, five with laminectomy only and ten with SCI produced using a dynamic weight - drop model). MR DAI was performed four times (1, 24, 48 and 168 hours after surgery) at 4.7 T with diffusion gradients applied parallel and perpendicular to the spine. Diffusion parameters (lADC, tADC and AI) were calculated for defined regions of white and gray matter. Epidural hematoma which appeared after laminectomy compressed spinal cord and caused a decrease of apparent diffusion coefficient (ADC) values in GM and WM. SCI in WM produced a decrease of lADC and increase in tADC. In GM an increase in both lADC and tADC values after SCI was observed. MR DAI will disclose dynamic changes in water diffusion during the first days after spinal cord contusion.

12.
Ginekol Pol ; 60(6): 301-5, 1989 Jun.
Artigo em Polonês | MEDLINE | ID: mdl-2638296

RESUMO

Lower concentrations of selenium and vitamin E were found in the serum of 50 women with malignant neoplasms of the genitals as compared with the concentrations in 55 healthy women family members of the patients living with them in common households. The degree of concentration decrease of these substances in the serum depended on the location of the tumour, and in cases of cervical neoplasms was 28% for selenium and 12% for vitamin E of the values in controls while in cases of ovarian neoplasms it was 34% and 37% respectively and in endometrial tumours it was 40% and 23% respectively. The third studied group comprised 36 healthy subjects not belonging to the families of the patients. The highest concentrations of selenium and vitamin E were found in the serum in the third group of women. The results suggest that various family factors not analysed in this study affect the concentrations of selenium and vitamin E in the serum of women with malignant neoplasms of genitals and in their family members.


Assuntos
Neoplasias dos Genitais Femininos/sangue , Selênio/sangue , Vitamina E/sangue , Adulto , Feminino , Neoplasias dos Genitais Femininos/genética , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/sangue , Neoplasias do Colo do Útero/sangue , Neoplasias Uterinas/sangue
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