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1.
Int J Legal Med ; 138(3): 801-814, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37980281

RESUMO

Examination of hair with its intact root is commonly used for DNA profiling of the donor. However, its use for gathering other types of information is less explored. Using attenuated total reflectance-Fourier transform infrared spectroscopy, the present study aims to explore other relevant aspects in a non-destructive manner for forensics. Determining the sex and blood group of human hair samples were the major goals of the study. Sex determination was accomplished by analyzing the differential vibrational intensities and stretching of various chemical groups associated with hair and its proteins. Statistical inference of spectral data was performed using chemometric algorithms such as PCA and PLS-DA. The PLS-DA model determined sex with 100% accuracy and blood grouping with an average accuracy of 95%. The present study is the first of its kind to determine sex and blood grouping from human scalp hair shafts, as far as the author knows. By acting as a preliminary screening test, this study could have significant implications for forensic analysis of crime scene samples. Human and synthetic hair were used in validation studies, resulting in 100% accuracy, specificity, and sensitivity, with 0% false positives and false negatives. The technique ATR FTIR spectroscopy could complement the currently used methods of hair analysis such as physical examination and mitochondrial or genomic DNA analysis.


Assuntos
Tipagem e Reações Cruzadas Sanguíneas , Quimiometria , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Cabelo , Impressões Digitais de DNA , Análise Discriminante , Análise dos Mínimos Quadrados , Proteínas Mutadas de Ataxia Telangiectasia
2.
J Synchrotron Radiat ; 27(Pt 6): 1633-1639, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33147189

RESUMO

Transition elements exhibit strong correlations and configuration interactions between core and valence excited states, which give rise to different excitations inside materials. Nickel exhibits satellite features in its emission and absorption spectra. Effects of such transitions on the optical constants of nickel have not been reported earlier and the available database of Henke et al. does not represent such fine features. In this study, the optical behaviour of ion beam sputter deposited Ni thin film near the L2,3-edge region is investigated using reflection spectroscopy techniques, and distinct signatures of various transitions are observed. The soft X-ray reflectivity measurements in the 500-1500 eV photon energy region are performed using the soft X-ray reflectivity beamline at the Indus-2 synchrotron radiation source. Kramers-Kronig analysis of the measured reflectivity data exhibit features corresponding to spin orbital splitting and satellite transitions in the real and imaginary part of the refractive index (refraction and absorption spectra). Details of fine features observed in the optical spectra are discussed. To the best of our knowledge, this is the first study reporting fine features in the measured optical spectra of Ni near its L2,3-edge region.

3.
J Synchrotron Radiat ; 26(Pt 4): 1152-1160, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31274439

RESUMO

Deposition of synchrotron-radiation-induced carbon contamination on beamline optics causes their performance to deteriorate, especially near the carbon K edge. The photon flux losses due to carbon contamination have spurred researchers to search for a suitable decontamination technique to restore the optical surface and retain its performance. Several in situ and ex situ refurbishing strategies for beamline optics are still under development to solve this serious issue. In this work, the carbon contamination is removed from a large (340 mm × 60 mm) Au-coated toroidal mirror surface using a capacitively coupled low-pressure RF plasma. Before and after RF plasma cleaning, the mirror was characterized by Raman spectroscopy, soft X-ray reflectivity (SXR) and atomic force microscopy (AFM) techniques. The Raman spectra of the contaminated mirror clearly show the G (1575-1590 cm-1) and D (1362-1380 cm-1) bands of graphitic carbon. The SXR curve of the contaminated mirror shows a clear dip near the critical momentum transfer of carbon, indicating the presence of carbon contamination on the mirror surface. This dip disappears after removal of the contamination layer by RF plasma exposure. A decrease in the intensities of the CO bands is also observed by optical emission spectrometry during plasma exposure. The AFM and SXR results suggest that the root-mean-square (r.m.s.) roughness of the mirror surface does not increase after plasma exposure.


Assuntos
Ouro/química , Gases em Plasma , Ondas de Rádio , Microscopia de Força Atômica , Óptica e Fotônica , Análise Espectral Raman/métodos , Síncrotrons
5.
Rev Sci Instrum ; 95(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38364036

RESUMO

A versatile beamline for performing reflectivity, fluorescence, and absorption experiments in the soft x-ray region of 100-1500 eV is commissioned on a bending magnet port of the Indus-2 synchrotron source. A high vacuum 2-axis reflectometer with x, y, and z sample scanning stages is installed. This reflectometer is used to measure the reflectivity of large samples up to 300 mm in length and 5 kg in weight. This feature is useful for characterizing x-ray optical elements, such as mirrors, gratings, and multilayers. A flange mounted silicon drift detector is installed in the downstream of the reflectometer for soft x-ray fluorescence measurements. The soft x-ray absorption measurements are carried out in the total electron yield and partial fluorescence yield modes. Integration of three different experimental techniques in the experimental station makes the beamline versatile for materials science applications as it provides structural, chemical, and electronic state information by performing the required experiments in an identical environment. The beamline uses a varied line spacing plane grating monochromator and gives a high flux (∼109 to 1011 photon/s) with a moderate resolution (λ/Δλ ~1000-5000). A three-mirror-based higher harmonic setup is incorporated to get rid of harmonics and to get a high spectral purity monochromatic beam with less than 0.1% harmonic content. In the present article, the beamline optical scheme, mechanical configuration, and details of the experimental setups are presented, along with a few representative results of each experimental mode.

6.
Curr Urol ; 17(2): 125-129, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37691983

RESUMO

Background: Purple urine bag syndrome (PUBS) is an unusual condition in which a purple discoloration of urine and bag occurs in people with urinary catheters. People with purple urine usually do not complain of any symptoms. The purple discoloration of the urine bag is often the only finding, frequently noted by caregivers. Materials and methods: This prospective observational study was conducted at our tertiary care institute from June 2018 to May 2020. A total of 46 patients with PUBS were included in this study. The objective of our study was to record the prevalence of each predisposing factor and to correlate the pathological mechanism through which the PUBS is manifested. Results: The mean age of PUBS patients was 67.4years and 67.4% were males. Most patients of PUBS (60.9%) had a urethral catheter, while there was percutaneous nephrostomy in 26.1% patients and 13% patients had a percutaneous suprapubic cystostomy catheter. Among the patients, 69.65% were bedridden or in an institutionalized situation, 73.9% were suffering from chronic constipation, 21.7% were associated with dementia, and 47.8% were cerebrovascular accidents with hemiparesis patients. In addition, 93.5% of patients presented with alkaline urine and 3 patients with acidic urine. The most common bacteria isolated in urine culture were E coli and Pseudomonas. Conclusions: Urinary catheter associated urinary tract infection and PUBS is most commonly documented in females, but our study showed that it is more common in males. The appearance of a purple bag does not depend on the material and type of the catheter or the catheterization method. In addition, no correlation was found between the microorganisms isolated from the environment and patients' urine.

7.
Sci Justice ; 61(1): 61-71, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33357828

RESUMO

Inhalant abuse is a serious and ever-evolving problem for our society. Inhalants are abused more commonly by teenagers and adolescents. Inhalants such as glue, paint thinners, correction fluid, and nail paint remover are easily available in the market which makes them readily abused. Out of various methods of abuse, huffing (placing a piece of cloth soaked with inhalant is placed in the mouth), bagging (placing head in a polythene bag containing inhalant), and ballooning (balloons filled with inhalant are used for inhaling vapors through the mouth) are most common. Inhalant abuse results in multiple target organ dysfunction with neuritis and brain damage due to the dissolution of the myelin sheath. In acute poisoning cases, it might cause death due to asphyxia and sudden sniffing syndrome. In such cases, various articles containing traces of inhalants could be retrieved from the scene of incidence and to detect these traces become an important facet of the investigation. However, it might be difficult due to the rapid evaporation of inhalants and the formation of reaction product species. In the present study, an attempt has been made to study the effect of three substrates (balloon, cloth, polythene) on component profiles of four paint thinners and four nail paint removers. The study suggests that although some components are retained, there is the formation of a large number of reaction product species and these must be taken into consideration before furnishing the opinion. These reaction product species might also be inhalant specific which must be further explored.


Assuntos
Abuso de Inalantes , Transtornos Relacionados ao Uso de Substâncias , Administração por Inalação , Adolescente , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Polietileno , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
8.
Urol Ann ; 13(1): 36-40, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33897162

RESUMO

INTRODUCTION: Management of chyluria with initial conservative approach and then using endoscopic sclerotherapy is a mainstay approach. However, a wide range of sclerosants are available with differential success rates and complication rates. This study evaluated the safety and efficacy of a single-dose instillation of 1% povidone iodine for the treatment of chyluria. MATERIALS AND METHODS: This was a prospective, observational study conducted on patients with chyluria who did not respond to conservative management with dietary restriction and diethylcarbamazine. The site of chyle efflux was identified by cystoscopy. A 6 Fr ureteral stent was inserted into effluxing side, diluted contrast was injected to delineate the pelvicalyceal system and the pyelolymphatic connection (arborization of the pelvicalyceal system), and a single-dose of 1% povidone iodine was instilled. Patients were observed for loin pain, fever, and disappearance of milky urine postinstillation and followed up at intervals of 3 months for a total duration of 1 year. RESULTS: Of a total 50 patients included, 35 were men and 15 were women, with a mean age of 37 years. Pyelolymphatic connections were noted in 48% of the patients. All patients showed an immediate disappearance of milky urine. During 1-year follow-up, 92% of the patients were symptom-free till the last follow-up while only 8% of the patients experienced recurrence of chyluria which were treated with other treatment modalities. The mean duration of recurrence was 8 weeks. CONCLUSION: Single dose of 1% povidone iodine was effective in immediate clearance of milky urine and well tolerated in patients with chyluria during 1-year follow-up.

9.
Forensic Sci Int ; 295: e1-e5, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30638754

RESUMO

In recent decades vibrational spectroscopy especially infrared (IR) spectroscopy has emerged as a fast, sensitive, and reliable technique in classifying alcoholic beverages based on geographic origin. However, Attenuated total reflectance (ATR) - Fourier transform infrared (FTIR) spectroscopy has not been used in many studies. In the present study, an attempt has been made to classify 75 samples of illicit liquor from different regions of India based on their geographical origin. The samples were scanned in the MIR range of 600-3000cm-1. It was observed that while using PCA 76% accuracy was obtained and while using LDA 93% accuracy was obtained. The samples of Delhi, Mansa, Patiala, Pathankot, and Fatehgarh Sahib show 100% classification with LDA whereas the samples from Ferozpur and Gurdaspur showed a 75% correct classification. These results point out toward the potential applicability of ATR-FTIR for the classification of alcoholic beverages based on the geographic origin.

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