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In this study, NAC-capped CdTe/CdS/ZnS core/double shell QDs were synthesized in an aqueous medium to investigate their utility in distinguishing normal DNA from mutated DNA extracted from biological samples. Following the interaction between the synthesized QDs with DNA extracted from leukemia cases (represents damaged DNA) and that of healthy donors (represents undamaged DNA), differential fluorescent emission maxima and intensities were observed. It was found that damaged DNA from leukemic cells DNA-QDs conjugates at 585 nm while intact DNA (from healthy subjects) DNA–QDs conjugates at 574 nm. The obtained results from the optical analyses indicate that the prepared QDs could be utilized as probe for detecting disrupted DNA that is associated with a number of diseases including malignancies. Additionally, the manufactured NAC-CdTe core with CdS shell and ZnS shell QDs were further characterized by high-resolution transmission using field emission scanning electron microscopy (FESEM), energy dispersive X-ray fluorescence (EDX), X-ray diffraction (XRD), infrared spectrum (IR), UV-vis absorbance, photoluminescence (PL) and absorbency intensity using the fully automatic ELISA. The XRD results revealed the formation of NAC-CdTe/CdS/ZnS QDs with a grain size of 5.7 nm. While EDX assay emphasizes the compound content of Cd, S, Zn and Te elements. Whereas SEM test's findings propose the spherical size of NAC- CdTe/CdS/ZnS QDs within the range of 10–40 nm. The demonstrated mono-dispersed lattice structure of NAC-CdTe core with CdS shell and ZnS shell QDs has superior PL emission properties at λ e m i of ∼ 600 nm and UV-Vis absorption bands at 350 nm. Overall, this study suggests that the synthesized QDs could be employed in developing optical biosensors for a variety of biomedical applications to improve early detection of diseases marked by damaged DNA profile including cancers. [ABSTRACT FROM AUTHOR]

High frequency (HF) transmitter implemented with the multioctave broadband power amplifier (PA) is always faced with the problem of interfering harmonics because of the nonlinearity of the PA. With the harmonic‐cancelation digital predistortion (HC‐DPD) scheme, the harmonics at lower frequencies can be canceled by the injected components and the harmonics at higher frequencies can be filtered out using a low‐pass filter (LPF). However, the HC‐DPD scheme brings the problem of unwanted spurs while lowering the requirements for sampling rate. In this article, a time‐delay neural network (TDNN) model is used to replace the conventional memory polynomial (MP) model in the forward modeling. Theoretical derivation and simulation results validate the effectiveness of the TDNN model in harmonic cancelation and spur suppression. Further, a frequency‐agile neural network (FANN) model is proposed based on the TDNN model. By adding the carrier frequency to the inputs of the network, the trained model can apply to all the trained carrier frequencies and is more friendly to the frequency‐hopping scenarios. Experiments were carried out on a 2–30 MHz HF transmitter testbench. Measurement results show that the harmonic‐to‐fundamental power ratio, the adjacent channel power ratio (ACPR), and the error vector magnitude (EVM) performances were all improved by more than 20 dB. Compared with the MP model, the unwanted spurs can be suppressed by up to 22 dB. In addition, the number of total model coefficients of the proposed FANN model is only 22% of that of the TDNN model under the frequency‐hopping scenario. [ABSTRACT FROM AUTHOR]