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1.
Electrophoresis ; 43(3): 425-436, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34596915

RESUMO

The questions on which judges/prosecutors apply for expertise are mostly about by whom a document was drafted/signed. In this study, a new collective strategy was constructed including a collection method, a modified-silica-based DNA isolation method, and a novel purification method on four contact traces formed on four different paper surface during writing, using PCR with AmpFlSTR®GlobalFiler™ STR kit (after experimental comparison between three different kits) and identification using CE. This collective analysis approach is more sensitive and superior to its equivalents on questioned documents in literature because quantifiable amounts of touch DNA and profiles with high loci percentages (100% on day 1, 72.72% after 1 week) were obtained up to 1 week even after the most challenging conditions of sample forming that a forensic scientist can meet; as washing hands just before drafting and using a very low pressure in a shorter time (simulating a simple contact real conditions while drafting), using no visualizing technique that damages the document. Using the strategy, four most commonly used paper types were compared, to see in which of them DNA could be recovered better. The success of this strategy was shown on the 1-day to 10-year-old real samples from a diary and some archive documents from a law office (including the mix-DNA and different ballpoint pens). Thus, it became possible to show if a person had touched the document, in high success rates up to 1 week as a secondary evidence, when primary evidences are insufficient for the detection of document fraud offenses.


Assuntos
Impressões Digitais de DNA , Tato , DNA/análise , Humanos , Repetições de Microssatélites , Reação em Cadeia da Polimerase
2.
J Forensic Sci ; 65(2): 661-663, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31617942

RESUMO

Ink dating is a significant problem in terms of forensic science. Ballpoint pens are generally used as writing tools on the documents. Aging is determination of the changes in dyes and solvents in the composition of ink over time by analytical methods. The evaporation of the solvents from the paper surface is faster than the decomposition process of the dyes. In this study, in 2017, we were asked by the court to determine whether the texts on the suspicious pages of an agenda dated 1996 were written within 2 years or earlier. Phenoxyethanol and dyes were examined in the composition of all suspected ink samples. The results show the determination of both the decomposition process of the dyes and the evaporation process of phenoxyethanol in the aging of the document entries written by ballpoint pen.


Assuntos
Corantes , Etilenoglicóis , Ciências Forenses/métodos , Violeta Genciana , Tinta , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Fatores de Tempo
3.
Chem Biol Interact ; 291: 29-39, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29885857

RESUMO

BACKGROUND: Epidemiological studies indicate that aspirin consumption reduces the risk of tumors, which is especially relevant for colonic adenoma and carcinoma. Similar observations were made for glial brain tumors and breast cancers, yet the results are inconsistent. Gentisic acid (GA) is a minor catabolite of aspirin; yet humans carrying CYP2C9-variants incapable to catabolize aspirin to GA do not benefit from aspirin in prevention against colonic adenoma. GA blocks binding of Fibroblastic Growth Factor to its receptor and its sulphonate metabolite dobesilic acid blocks growth of C6 glioblastoma in vivo. GA is also an endogenously produced siderophore in mammalians for the transport of iron, a trace element which stimulates tumor growth and enhances anthracycline cardiotoxicity. MATERIALS AND METHODS: In this study, we assessed whether GA exerts direct antitumor activity on C6 glioma cells in vitro (cytotoxicity, colony growth, 3H-thymidine labeling analysis of DNA synthesis); and whether it can modify growth of Ehrlich breast ascites carcinoma (EAC) and solid tumors (EST) in vivo. GA and antitumoral trace element selenium block 12-lipoxygenase activity and aspirin's paradoxical inflammatory effects are seen in selenium-deficient humans; thus, we also investigated antitumor interactions between GA and sodium selenite. Lastly, we evaluated whether GA could protect against doxorubicin cardiotoxicity due to its function to chelate iron. RESULTS: Clinically achievable doses of GA blocked growth, colony formation and DNA synthesis of C6 glioma in vitro with high significance. GA enhanced the survival of EAC-bearing mice at a dosage of 0.4 mg/mice/day, in which 33% of the treated animals survived more than 3-weeks, when all untreated mice succumbed to their tumors. Selenium decreased EST volumes initially, yet increased tumor volumes at later stages in surviving mice. GA alone reduced solid tumor growth and did not modify selenite antineoplasticity initially, but blocked the late tumor-stimulating effects of selenite. Lastly, doxorubicin-induced cardiac myofibrillary and endothelial damage and hyalinization necrosis were attenuated with GA treatment. CONCLUSIONS: GA highly merits to be studied in further animal models as an anticancer and chemoprotective drug.


Assuntos
Aspirina/uso terapêutico , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/prevenção & controle , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/prevenção & controle , Cardiotônicos/uso terapêutico , Gentisatos/metabolismo , Animais , Aspirina/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Carcinoma de Ehrlich/tratamento farmacológico , Carcinoma de Ehrlich/patologia , Cardiotônicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Masculino , Camundongos Endogâmicos BALB C , Miocárdio/patologia , Miocárdio/ultraestrutura , Fase S/efeitos dos fármacos , Selenito de Sódio/farmacologia , Selenito de Sódio/uso terapêutico , Análise de Sobrevida
4.
Int J Neurosci ; 128(9): 865-877, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29383986

RESUMO

Cardiac glycosides induce a strong immunological cancer cell cytotoxicity, in which the released intracellular components of dying tumor cells (e.g. calreticulin, HMGB1 and ATP) stimulate immunity and help in eradicating cancer. Among the cardiac glycosides, oleandrin is an inhibitor of P-glycoprotein expression and exerts excellent penetration through the blood-brain barrier which also harbors neuroprotective and anti-glioma efficacies. Cardiac glycosides also exert neuroprotective activities, one explanation for such an action is the metabolic arrest as a defense strategy against hypoxia. Recently, it was also shown that oleandrin increases survival of glioma-implanted mice alone and in synergy with temozolomide, which also associated with the release of brain derived neurotrophic factor and activation of its receptor TrkB. In conclusion, oleandrin strongly deserves to be studied as a candidate molecule in treatment of neurodegenerative and neurooncological diseases.


Assuntos
Cardenolídeos/uso terapêutico , Glicosídeos Cardíacos/uso terapêutico , Glioblastoma/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Glicosídeos Cardíacos/metabolismo , Humanos
5.
Egypt J Forensic Sci ; 7(1): 9, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28775902

RESUMO

BACKGROUND: The case relates to a bookstore owner claiming that two DM-41 hand grenades were exploded simultaneously in his store. There were three males together at the store when the explosion occurred. One was the owner who claimed that he escaped after the explosion without any harm; the other was at the corner lying down to prevent his body from the explosion effect. He survived with very minor, almost no effects. CASE PRESENTATION: According to the hospital report, it was stated that "cuts on the right femur with sizes of 0.5x2 and 0.5x1 cm and one cut of 0.5x2,0 cm on the left food which are curable with simple medical intervention; generalized skin erosions on body with the sizes between 0,5 to 1,0 cm"; the third male was standing and killed. He was next to the lying down male. At the autopsy report it was stated that the he was killed due to the shrapnel/fragmentation effect, breaks on humerus, radius, femur and cranium; cerebral and internal hemorrhage. The males witnessed at the court that they had survived with no vital damage on their bodies, they had seen the perpetrators and heard them talking. With the fact that the deceased male was intensively affected with the fragmentation/shrapnel due to the autopsy report, it was the court's wonder if it is possible for the survived men to have no or very minor nonfatal fragmentation effect on their bodies even being in the same room with the deceased. CONCLUSION: It was mainly aimed to test the fragmentation effect of 2 DM-41 defence hand grenades when detonated in a closed environment (an empty room with the approximately same size of the related case). The test room was empty with no secondary fragmentation sources as window glasses etc. 3 male mannequins were used as test materials. With the post blast reconstruction of the crime scene, it was aimed to determine if the test results and the autopsy report are very coherent and the persons having the direct blast effect would be expected having maximum exposure to the fragmentation.

6.
Anal Sci ; 32(6): 611-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27302580

RESUMO

Direct analyses of explosives in soil using liquid chromatography tandem mass spectrometry (LC-MS/MS) methods are very limited in the literature and require complex procedures or relatively high amount of solvent. A simple and rapid method was developed for the determination of pentaerythritol tetranitrate (PETN), 3,5-trinitro-1,3,5-triazacyclohexane (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), which are among the explosives used in terrorist attacks. A one-step extraction method for 1.00 g soil with 2.00 mL acetonitrile, and a 8-min LC-MS/MS method was developed. The detection limits for PETN, RDX and HMX were 5.2, 8.5 and 3.4 ng/g and quantitation limits were 10.0, 24.5, 6.0 ng/g. The intermediate precisions and Horwitz Ratio's were between 4.10 - 13.26% and 0.24 - 0.98, in order. This method was applied to a model post-blast debris collected from an artificial explosion and real samples collected after a terrorist attack in Istanbul. The method is easy and fast and requires less solvent use than other methods.

7.
Artigo em Inglês | MEDLINE | ID: mdl-27107852

RESUMO

Date-rape drugs have the potential to be used in drug-facilitated sexual assault, organ theft and property theft. Since they are colorless, tasteless and odorless, victims can drink without noticing, when added to the beverages. These drugs must be detected in time, before they are cleared up from the biofluids. A simultaneous extraction and determination method in urine for GHB, ketamine, norketamine, phenobarbital, thiopental, zolpidem, zopiclone and phenytoin (an anticonvulsant and antiepileptic drug) with LC-MS/MS was developed for the first time with analytically acceptable recoveries and validated. A 4 steps liquid-liquid extraction was applied, using only 1.000mL urine. A new age commercial C18 poroshell column with high column efficiency was used for LC-MS/MS analysis with a fast isocratic elution as 5.5min. A new MS transition were introduced for barbital. 222.7>179.8 with the effect of acetonitrile. Recoveries (%) were between 80.98-99.27 for all analytes, except for GHB which was 71.46. LOD and LOQ values were found in the ranges of 0.59-49.50 and 9.20-80.80ngmL(-1) for all the analytes (except for GHB:3.44 and 6.00µgmL(-1)). HorRat values calculated (between 0.25-1.21), revealed that the inter-day and interanalist precisions (RSD%≤14.54%) acceptable. The simultaneous extraction and determination of these 8 analytes in urine is challenging because of the difficulty arising from the different chemical properties of some. Since the procedure can extract drugs from a wide range of polarity and pKa, it increases the window of detection. Group representatives from barbiturates, z-drugs, ketamine, phenytoin and polar acidic drugs (GHB) have been successfully analyzed in this study with low detection limits. The method is important from the point of determining the combined or single use of these drugs in crimes and finding out the reasons of deaths related to these drugs.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Hipnóticos e Sedativos/urina , Extração Líquido-Líquido/métodos , Compostos Azabicíclicos/química , Compostos Azabicíclicos/isolamento & purificação , Compostos Azabicíclicos/urina , Barbitúricos/química , Barbitúricos/isolamento & purificação , Barbitúricos/urina , Ciências Forenses , Humanos , Hipnóticos e Sedativos/química , Hipnóticos e Sedativos/isolamento & purificação , Ketamina/química , Ketamina/isolamento & purificação , Ketamina/urina , Limite de Detecção , Modelos Lineares , Fenitoína/química , Fenitoína/isolamento & purificação , Fenitoína/urina , Piperazinas/química , Piperazinas/isolamento & purificação , Piperazinas/urina , Piridinas/química , Piridinas/isolamento & purificação , Piridinas/urina , Estupro , Reprodutibilidade dos Testes , Oxibato de Sódio/química , Oxibato de Sódio/isolamento & purificação , Oxibato de Sódio/urina , Zolpidem
8.
Int J Psychiatry Clin Pract ; 19(3): 201-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25666858

RESUMO

OBJECTIVE: Panic disorder (PD) is an anxiety disorder characterized by sudden attacks of intense fear. Biochemical studies suggest that oxidative stress (OS) index is significantly higher in PD, and OS genes may participate in development of anxiety-like behavioral phenotypes. We aimed to investigate role of polymorphisms in OS gene, glutathione peroxidase-1 (GPX1), and DNA repair enzyme gene, 8-oxoguanine glycosylase-1 (OGG1), in PD patients. METHODS: GPX1 Pro198Leu (rs1050450) and OGG1 Ser326Cys (rs1052133) polymorphisms of 127 patients with PD and 151 disease-free controls were analyzed with real-time polymerase chain reaction. Severity of PD symptoms was assessed by Panic and Agoraphobia Scale (PAS). RESULTS: No significant relationship was found in genotype distributions of OGG1 Ser326Cys and GPX1 Pro198Leu polymorphisms between PD and control groups (p > 0.05). There was no significant relationship between OGG1 or GPX1 polymorphisms, and age of onset, agoraphobia, or PAS scores in PD group (p > 0.05). However, in GPX1 Pro198Leu polymorphism, C allele (Pro) was found to be more frequent in female subgroup of PD patients compared with that in males (p = 0.027). CONCLUSIONS: GPX1 Pro198Leu and OGG1 Ser326Cys polymorphisms were not associated with PD risk in Turkish patients. However, a gender-specific effect of GPX1 Pro198Leu C allele may be associated with PD development.


Assuntos
DNA Glicosilases/genética , Glutationa Peroxidase/genética , Estresse Oxidativo/genética , Transtorno de Pânico/genética , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Fatores Sexuais , Adulto Jovem , Glutationa Peroxidase GPX1
9.
Talanta ; 132: 222-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25476301

RESUMO

Lead is a hazardous compound that affects the central nervous system in people, particularly children, and may cause some reversible and irreversible diseases. Legal regulations try to prevent the exposure from products especially produced for children such as coating paints, jewelry, toys, bed linen, textile, etc. The aim of this study was to determine the lead levels of coating paints on children׳s outwear selling in district bazaar by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and to specify the percent of non-complying samples. Here we described the solid matrix calibration method and confirmed the results with the microwave-assisted acid digestion method. Both comparative methods were validated by analysis of the certified reference materials (NIST SRM-612 glass matrix, NIST SRM-2582 powdered paint and ERM-EC681k) and bias% for accuracy and RSD% for precision were calculated lower than 6.8% and 7.3%, respectively. The recovery ranges of laser ablation and microwave-assisted acid digestion method for Pb were found to be between 88.2-98.1% and 95.3-101.3%, respectively. The limits of detection values were determined as 0.162 mg kg(-1) for direct sampling in the ablation chamber and 0.002 ng mL(-1) for aqueous solutions. Correlation result of 16 samples (r=0.99) examined in both methods was satisfactory. In coating paint samples, 14.65% of 198 (n=29) did not comply with the 90 mg kg(-1) lead limit according to regulation. Validated quantitative laser ablation method may be preferred to quickly and reliably determine the Pb levels in other solid samples as well as coating paints.


Assuntos
Chumbo/isolamento & purificação , Pintura/análise , Extração em Fase Sólida/métodos , Têxteis/análise , Calibragem , Criança , Humanos , Lasers , Limite de Detecção , Micro-Ondas , Espectrofotometria Atômica
10.
J Biomed Opt ; 19(5): 057006, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24817623

RESUMO

The main purpose of this study is to establish radiation-safe scanning of passersby at high security areas, such as airports and customs. The stomach was selected as the organ to be analyzed. In order to determine whether a substance found inside a human body as wrapped in a plastic bag is filled narcotics or not, many substances in white powder form including morphine-HCL were inspected. Inspection was carried out with on-ionizing radiation by irradiating stomach tissue with laser light. Optical transmittance of lamb stomach tissue was analyzed at different wavelengths. We showed that detection by 650-nm diode laser irradiation would be suitable for such a radiation-safe scan. Different materials were also investigated for absorptive properties, and closed system Raman studies were performed. The spectrum of a molecule found inside white powder placed behind the lamb stomach tissue was detected as a fingerprint. This allowed the detection of target substances without any physical contact or damage to the biological tissue.


Assuntos
Ciências Forenses/métodos , Lasers de Estado Sólido/efeitos adversos , Estômago/efeitos da radiação , Detecção do Abuso de Substâncias/métodos , Animais , Tráfico de Drogas , Derivados da Morfina/química , Ovinos , Análise Espectral , Estômago/patologia , Detecção do Abuso de Substâncias/efeitos adversos
12.
Turk J Pediatr ; 54(3): 283-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23094539

RESUMO

Munchausen syndrome by proxy is a kind of child abuse in which affected children are often hospitalized for long periods and endure repetitive, painful and expensive diagnostic attempts. We present herein two toxicologically confirmed cases of Munchausen syndrome by proxy. Case 1 is a 16-month-old male who had fever, peripheral cyanosis, tremor, and reported cardiac arrest. Symptoms recurred in the hospital when the mother administered fluids. Toxicology detected 3.5 ng/ml mercury (Hg) in the fluid and 9.4 microg Hg/g creatinine in the urine. Case 2 is a 14-year-old female who had irregular blood findings and multiple hospitalizations. Serum analysis detected warfarin. Both mothers were transferred to psychiatric care. Munchausen syndrome by proxy should be suspected when clinical/laboratory findings are negative, illness descriptions are inconsistent, and frequent hospitalization yields no diagnosis. Psychiatric evaluation and toxicological analysis are recommended.


Assuntos
Intoxicação por Mercúrio/diagnóstico , Mães/psicologia , Síndrome de Munchausen Causada por Terceiro/diagnóstico , Varfarina/intoxicação , Adolescente , Feminino , Humanos , Lactente , Masculino
13.
J Gynecol Oncol ; 21(4): 248-54, 2010 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-21278887

RESUMO

OBJECTIVE: To evaluate the role of lysophosphatidic acid (LPA) as a tumor marker in diagnosis and follow-up of patients with epithelial ovarian cancer. METHODS: Eighty-seven epithelial ovarian cancer patients, 74 benign ovarian tumor patients, and 50 healthy women were enrolled in the study. Twenty-nine of 87 epithelial ovarian cancer patients were followed up for 6 cycles of paclitaxel-carboplatin chemotherapy. CA-125 and total plasma LPA levels were measured preoperatively and before each chemotherapy cycle. RESULTS: Preoperative total plasma LPA and serum CA-125 levels were significantly higher in patients with epithelial ovarian cancer compared to patients with benign ovarian tumors and healthy women. Cut-off value for LPA was determined as 1.3 µmol/L and sensitivity, specificity, positive predictive value and negative predictive value were 95%, 92%, 95% and 92%, respectively. Mean total plasma LPA level of 29 patients who received chemotherapy was 7.21±6.63 µmol/L preoperatively and 6.84±6.34 µmol/L, 6.34±5.92 µmol/L, 6.14±5.79 µmol/L, 5.86±5.68 µmol/L, 5.23±5.11 µmol/L and 5.21±5.32 µmol/L in measurements held just before the 1st, 2nd, 3rd, 4th, 5th and 6th chemotherapy cycles, respectively (ANOVA, p=0.832). Total plasma LPA levels decreased slightly with chemotherapy administration and there was a weak negative correlation (Spearman, r(s)=-0.151, p=0.034), compared to a significant negative correlation in CA-125 (Spearman, r(s)=-0.596, p<0.001). CONCLUSION: LPA is a better biomarker for diagnosis of epithelial ovarian cancer compared to CA-125. However, measurement of total plasma LPA levels during chemotherapy administration have no superiority to the serum CA-125 levels.

14.
Forensic Sci Int ; 156(2-3): 91-4, 2006 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-16410157

RESUMO

The aim of this study is to predict how long after time of death a buried body could be analyzed for opiates in soft tissues and to show the accessibility and suitability of bone marrow as a useful toxicological specimen from buried bodies. Morphine solutions were injected in nine albino rabbits. Doses ranged from 0.3 to 1.1 mg/kg with 0.1 mg/kg increments. One hour after the injections, the rabbits were sacrificed. Blood, urine and bone marrow samples were collected for analysis. After the whole bodies were buried, femur bone marrow specimens were collected on the seventh and fourteenth days. CEDIA was used to monitor morphine contents of the collected samples. All experimental cases showed that the increase in the given morphine doses correlated with the increase in blood and bone marrow morphine concentrations. High morphine concentrations were detected in urine samples, but there was no correlation between the urine and blood or urine and bone marrow morphine concentrations. Statistically meaningful increases in bone marrow morphine concentrations were found parallel to increase of blood morphine concentrations. Seventh and fourteenth day postmortem morphine concentrations also followed this correlation. Morphine concentrations in bone marrow at 7 and 14 day postmortem decreased consistently when compared with bone marrow morphine concentrations collected immediately after death. We conclude that in sudden death when other specimens are unavailable due to degradation, bone marrow can be a most useful specimen. Further experimental research in this area is required to validate bone marrow as an alternative tissue.


Assuntos
Medula Óssea/química , Morfina/análise , Entorpecentes/análise , Mudanças Depois da Morte , Animais , Fêmur/química , Medicina Legal , Morfina/administração & dosagem , Morfina/farmacocinética , Entorpecentes/administração & dosagem , Entorpecentes/farmacocinética , Coelhos , Detecção do Abuso de Substâncias/métodos , Fatores de Tempo
15.
Forensic Sci Int ; 141(1): 33-7, 2004 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-15066711

RESUMO

Soils vary among different areas, and have some characteristics because of the natural effects and transfers made by human and other living beings in time. So that forensic examination of soil is not only concerned with the analysis of naturally occurring rocks, minerals, vegetation, and animal matter. It also includes the detection of such manufactured materials such as ions from synthetic fertilizers and from different environments (e.g., nitrate, phosphate, and sulfate) as environmental artifacts (e.g., lead or objects as glass, paint chips, asphalt, brick fragments, and cinders) whose presence may impart soil with characteristics that will make it unique to a particular location. Many screening and analytical methods have been applied for determining the characteristics which differentiate and discriminate the forensic soil samples but none of them easily standardized. Some of the methods that applied in forensic laboratories in forensic soil discrimination are the color comparison of the normal air-dried (dehumidified) and overheated soil samples, macroscopic observation, and low-power stereo-microscopic observation, determination of anionic composition by capillary electrophoresis (CE), and the elemental composition by scanning electron microscope (SEM)-energy dispersive X-ray spectrometer (EDS) and other high sensitivity techniques. The objective of this study was to show the effect of the application of 9 tonnes/cm2 pressure on the elemental compositions obtained by SEM-EDS technique and comparing the discrimination power of the pressed-homogenized and not homogenized forensic soil samples. For this purpose soil samples from 17 different locations of Istanbul were collected. Aliquots of the well mixed samples were dried in an oven at 110-120 degrees C and sieved by using 0.5 mm sieve and then the undersieve fraction(<0.5 mm) of these samples put on an adhesive tape placed on a stub. About 100-150 mg aliquots of dried, sieved samples were pressed under 9 tonnes/cm2 pressure by KBr disk preparation apparatus of an infrared spectrophotometer. Surfaces of the randomized particles and the pressed disks of the soil samples were scanned and the elemental compositions were determined with scanning electron microscope JEO-JSM-5600 equipped with an energy dispersive X-ray spectrometer OXFORD Link-ISIS-300. The samples from top of the sieves were examined with stereo-microscope equipped with JVC-TK-128DE color video camera and JVC-GV-PT2, digital video printer. Natural and artificial materials that have characteristic features were identified. Then for additional confirmation all soil samples were dried at 120 degrees C and over 780 degrees C and their colors compared. We concluded that pressing the whole sieved soil samples under 9 tonnes/cm2 pressure results in smashing over the harder particles into the softer matrix and results in homogenization of the soil sample. The elemental compositions of these samples obtained by SEM-EDS with 10-fold less standard deviation (S.D.) values and so that with more reproducibility and discrimination power.


Assuntos
Medicina Legal/métodos , Microscopia Eletrônica de Varredura , Solo/análise , Espectrometria por Raios X , Pressão , Turquia
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