با سلام خدمت کاربران در صورتی که با خطای سیستم پرداخت بانکی مواجه شدید از طریق کارت به کارت (6037997535328901 بانک ملی ناصر خنجری ) مقاله خود را دریافت کنید (تا مشکل رفع گردد).
ردیف | عنوان | نوع |
---|---|---|
1 |
Toward a novel framework for bloodstains dating by Raman spectroscopy: How to avoid sample photodamage and subsampling errors
در راستای یک چارچوب جدید برای قدمت رگهای خونی توسط طیف سنجی رامان: نحوه جلوگیری از خطاهای عکسبرداری و نمونه برداری از نمونه-2020 Answers to questions about the time of bloodstains formation are often essential to unravel the sequence of
events behind criminal acts. Unfortunately, the relevance of preserved evidence to the committed offence usually
cannot be verified, because forensic experts are still incapable of providing an accurate estimate of the bloodstains’
age. An antidote to this impediment might be substituting the classical dating approach – founded on the
application of calibration models – by the comparison problem addressed using likelihood ratio tests. The key
aspect of this concept involves comparing the evidential data with results characterizing reference bloodstains,
formed during the process of supervised ageing so as to reproduce the evidence. Since this comparison requires
data that conveys information inherent to changes accompanying the process of blood decomposition, this study
provided a Raman-based procedure, designated for probing into the chemistry of ageing bloodstains. To circumvent
limitations experienced with single-point measurements – the risk of laser-induced degradation of
hemoglobin and subsampling errors – the rotating mode of spectral acquisition was introduced. In order to verify
the performance of this novel sampling method, obtained spectra were confronted with those acquired during
conventional static measurements. The visual comparison was followed by analysis of data structure using
regularized MANOVA, which boosted the variance between differently-aged samples while minimizing the
variance observed for bloodstains deposited at the same time. Studies of relation between these variances demonstrated
the superiority of novel procedure, as it provided Raman signatures that enabled a better distinction
between differently-aged bloodstains. Keywords: Bloodstains | Forensic dating | Raman spectroscopy | Rotating stage | Regularized MANOVA |
مقاله انگلیسی |