Nanoscale biomaterials for terahertz imaging: A non-invasive approach for early cancer detection.

Terahertz (THz) technology is developing a non-invasive imaging system for biosensing and clinical diagnosis. THz medical imaging mainly benefits from great sensitivity in detecting changes in water content and structural variations in diseased cells versus normal tissues. Compared to healthy tissues, cancerous tumors contain a higher level of water molecules and show structural changes, resulting in different THz absorption. Here we described the principle of THz imaging and advancement in the field of translational biomedicine and early detection of pathologic tissue, with a particular focus on oncology. In addition, although the main forte of THz imaging relies on detecting differences in water content to distinguish the exact margin of tumor, THz displays limited contrast in living tissue for in-vivo clinical imaging. In the last few years, nanotechnology has attracted attention to aid THz medical imaging and various nanoparticles have been investigated as contrast enhancements to improve the accuracy, sensitivity, and specificity of THz images. Most of these multimodal contrast agents take advantage of the temperature-dependent of THz spectrum to the conformational variation of the water molecule. We discuss advances in developing THz contrast agents to accelerate the advancement of non-invasive THz imaging with improved sensitivity and specificity for translational clinical oncology.

Delay coupled oscillators for frequency tuning of solid-state terahertz sources.

We present a solid-state tunable terahertz source that exploits the theory of coupled oscillators to simultaneously achieve high output power and frequency tuning. Our proposed structure effectively generates and combines high power harmonics from multiple synchronized solid-state oscillators in a loop configuration. We study the dynamics of the system, find the stable modes, and show how the structure can dynamically select a desired coupling mode. Using this method, we fabricated 0.29 and 0.32 THz tunable sources with peak output powers of 0.76 and 0.5 mW both in a standard 65 nm bulk complementary metal-oxide semiconductor technology. This power level is around 10,000 times larger than the state of the art which demonstrates that the proposed concept achieves significantly higher output power for a given solid-state process.

Evaluation of relationship between Rotavirus and Coronavirus infections with calf diarrhea by capture ELISA.

Rotavirus and Coronavirus are two main causes of severe diarrhea in human infants and many animal species worldwide. Calves up to 3 months old can be affected by these viruses. The importance of these viruses in cattle industry is due to substantial economic loss, treatment costs, and reduced growth rates in beef and dairy calves. Mixed infections caused by Rotavirus and Coronavirus can lead to severe form of diarrhea. In present case-control study, 261 samples of healthy and diarrheic calves from farms around Mashhad were collected. These samples were tested by antigen-capture enzyme-linked immunosorbent assay (Bio-X diagnosis kit). The results showed that the prevalence of Rotavirus and Coronavirus infection in diarrheic calves is 26.98% and 3.17%, respectively. Also, there was no significant relationship between infection with Rotavirus, Coronavirus, and diarrhea in the studied population.