50 research outputs found
Insights into polycrystalline microstructure of blood films with 3D Mueller matrix imaging approach
This study introduces a novel approach in the realm of liquid biopsies, employing a 3D Mueller-matrix (MM) image reconstruction technique to analyze dehydrated blood smear polycrystalline structures. Our research centers on exploiting the unique optical anisotropy properties of blood proteins, which undergo structural alterations at the quaternary and tertiary levels in the early stages of diseases such as cancer. These alterations manifest as distinct patterns in the polycrystalline microstructure of dried blood droplets, offering a minimally invasive yet highly effective method for early disease detection. We utilized a groundbreaking 3D MM mapping technique, integrated with digital holographic reconstruction, to perform a detailed layer-by-layer analysis of partially depolarizing dry blood smears. This method allows us to extract critical optical anisotropy parameters, enabling the differentiation of blood films from healthy individuals and prostate cancer patients. Our technique uniquely combines polarization-holographic and differential MM methodologies to spatially characterize the 3D polycrystalline structures within blood films. A key advancement in our study is the quantitative evaluation of optical anisotropy maps using statistical moments (first to fourth orders) of linear and circular birefringence and dichroism distributions. This analysis provides a comprehensive characterization of the mean, variance, skewness, and kurtosis of these distributions, crucial for identifying significant differences between healthy and cancerous samples. Our findings demonstrate an exceptional accuracy rate of over 90% for the early diagnosis and staging of cancer, surpassing existing screening methods. This high level of precision and the non-invasive nature of our technique mark a significant advancement in the field of liquid biopsies. It holds immense potential for revolutionizing cancer diagnosis, early detection, patient stratification, and monitoring, thereby greatly enhancing patient care and treatment outcomes. In conclusion, our study contributes a pioneering technique to the liquid biopsy domain, aligning with the ongoing quest for non-invasive, reliable, and efficient diagnostic methods. It opens new avenues for cancer diagnosis and monitoring, representing a substantial leap forward in personalized medicine and oncology
Self-Compensation Mechanism in Semi-Insulating CdMnTe Crystals Intended for X/γ-Ray Detectors
The electrical properties of single (x= 0.07 - 0.39) crystals with a resistivity of ≈ Ω cm at 300 K have been studied. The electrical conductivity is explained in the terms of statistics of electrons and holes in a semiconductor taking into account the compensation process in impurity-defect complexes. The energy of ionization and the degree of compensation levels have been found
Detector with High Internal Photocurrent Gain Based on ZnO:N
The photoresponsive structures prepared by magnetron sputtering of ZnO:N on p-Si substrates followed by vacuum evaporation of semi-transparent Ni film on ZnO surface were investigated. The mentioned structures show high sensitivity that sharply enhances with increase of applied voltage. Under a bias 5 V, the responsivities at λ = 390 and 850 nm are equal to 210 A/W and 110 A/W which correspond to the quantum efficiencies of 655 and 165, respectively. It is suggested that the observed high response is attributed to internal gain in phototransistor structure containing Ni/n-ZnO Schottky contact as emitter junction and n-ZnO/p-Si heterostructure as collector junction
Detector with High Internal Photocurrent Gain Based on ZnO:N
The photoresponsive structures prepared by magnetron sputtering of ZnO:N on p-Si substrates followed by vacuum evaporation of semi-transparent Ni film on ZnO surface were investigated. The mentioned structures show high sensitivity that sharply enhances with increase of applied voltage. Under a bias 5 V, the responsivities at λ = 390 and 850 nm are equal to 210 A/W and 110 A/W which correspond to the quantum efficiencies of 655 and 165, respectively. It is suggested that the observed high response is attributed to internal gain in phototransistor structure containing Ni/n-ZnO Schottky contact as emitter junction and n-ZnO/p-Si heterostructure as collector junction
Ultraviolet Detectors Based on ZnO:N Thin Films with Different Contact Structures
Al/ZnO:N/Al and Ni/ZnO:N/Al diode photodetectors fabricated by dc magnetron sputtering of ZnO:N films on p-Si substrates are studied. The photocurrent-to-dark current ratio equal to 250 at λ= 390 nm and the time constant of photoresponse about 10 μs for Al/ZnO:N/Al structures with 4 μm interdigital spacing was achieved. The Ni/ZnO:N/Al diode structure has the rectification ratio ≈10² at bias 1 V, the maximal responsivity about 0.1 A/W is observed at 365 nm, and the measured time constant of photoresponse is about 100 ns