On Zero-Shot Multi-Speaker Text-to-Speech Using Deep Learning

This thesis explores various aspects of zero-shot multi-speaker text-to-speech (TTS) synthesis using deep learning to create an effective system. A deep learning model for zero-shot multi-speaker TTS uses text and speaker identity as input to generate the respective output speech without fine-tuning for speakers not seen during training. The experiments consider a system with three main components: a speaker encoder network, a mel-spectrogram prediction network, and a vocoder network. A speaker encoder network captures the speaker identity in a fixed-sized speaker embedding. This speaker embedding is injected into a mel-spectrogram prediction network at one or more locations to generate a mel-spectrogram conditioned on the text and the speaker embedding. Finally, a vocoder network converts the mel-spectrogram into a waveform. All three components are trained separately. The speech synthesis aspects explored in the experiments include the speaker embedding injection method, speaker encoder network, speaker embedding injection location, and mel-spectrogram prediction network for the TTS system. The FiLM method from the visual reasoning field is adapted for the first time to inject speaker embeddings into the TTS workflow and compared against traditional methods. The significance of speaker embeddings is highlighted by comparing two well-established speaker embedding models. New combinations of speaker embedding injection locations are explored for two mel-spectrogram prediction networks. The best-performing model generates speech with naturalness ranging from fair to good, exhibits more than moderate speaker similarity, and shows potential for improvement. Additionally, the zero-shot multi-speaker TTS system is enhanced to generate fictitious voices

Identification of Promising Three-Way Hybrids of Pearl Millet for Drought-Prone Environments of North-Western India

Stable, drought-tolerant, and high-yielding dual-purpose hybrids are needed for cultivation in the drought-prone areas of India. Working towards this, this study was conducted to assess the associations between grain yield and its component traits and the relationships among genotypes to select the most promising hybrids based on multiple traits. In the present investigation, thirty newly developed three-way hybrids (TWHs), along with four popular commercial single-cross hybrids and two open pollinated varieties (OPVs) were evaluated at three sites in the drought-prone ecology of India during the rainy season of 2021–2022. A principal component analysis (PCA) revealed that the first three component axes (PC) were significant, with eigenvalues more than one, and together contributed to 74.10% of the total variance. A hierarchical cluster analysis based on the Euclidean distance between hybrids suggested the existence of three clusters. Cluster III (C-III) had hybrids with maximum grain yield, dry fodder yield, and important component traits such as panicle harvest index and grain harvest index that are required for adaptation to drought-prone environments. A genotype by yield X trait (GYT) biplot and a superiority index (SI) were generated to identify the best hybrids with high grain yield and other component traits. These results were used to identify TWHs, namely TH-114, TH-138, TH-49, TH-67, and TH-79, with more than 30% standard heterosis and stable performance coupled with better drought-adaptive traits

Changes in vitamin A conditioned hamster cheek pouch epithelium on exposure to commercial shell lime (calcium hydroxide) and tobacco. I. Optical histopathology

Epidemiologically a high incidence of oral cancer and addiction to tobacco, singly or in combination with other ingredients of the betel quid, are closely correlated. Attempts at the induction of malignancy in laboratory animals on exposure to these ingredients have hitherto failed. Studies are reported on cheek pouch epithelium of 152 Syrian golden hamsters exposed to commercial shell lime (calcium hydroxide) and tobacco, singly and in combination, with parallel conditioning by Vitamin A palmitate. The abnormal changes found especially in lime and lime-plus-tobacco treated epithelia are massive hyperplasia, keratinization anomalies, marked edema and dysplasia. The most significant findings are (1) greater epithelial alteration caused by lime, lime plus vitamin A, tobacco plus vitamin A, lime plus tobacco and lime plus tobacco and vitamin A, than by tobacco alone; (2) increasing epithelial dysplasia in response to longer periods of exposure to the test substances; and (3) enhancement of tissue changes in the presence of vitamin A

303 HISTOLOGICAL CHANGES IN THE ORAL MUCOSA OF THE WISTAR RAT TREATED WITH COMMERCIAL LIME (CALCIUM HYDROXIDE)-AN OPTICAL AND SUBMICROSCOPIC STUDY

THE high incidence of oral cancer in different population groups in man

Influence of excess of retinoid on DMBA carcinogenesis

This paper reports a study on the influence of excess of vitamin A palmitate on the induction and maintenance of oral tumors. Sixty four weanling Syrian hamsters were divided in four groups and painted three times a week, either with 0.5% DMBA or 15% vitamin A palmitate, singly or in combination. A possible mild immune response evoked by vitamin A palmitate is considered responsible for the delayed induction of the tumors. In all animals exposed to carcinogen + vitamin A the induced tumors were small in size and histologically verified as well differentiated epidermoid carcinomas. In control group with sole vitamin A palmitate application the cheek pouch showed considerably increased keratinization

Understanding genetic diversity in drought-adaptive hybrid parental lines in pearl millet.

Information on genetic diversity and population structure is helpful to strategize enhancing the genetic base of hybrid parental lines in breeding programs. The present study determined the population structure and genetic diversity of 109 pearl millet hybrid parental lines, known for their better adaptation and performance in drought-prone environments, using 16,472 single nucleotide polymorphic (SNP) markers generated from GBS (genotyping-by-sequencing) platforms. The SNPs were distributed uniformly across the pearl millet genome and showed considerable genetic diversity (0.337), expected heterozygosity (0.334), and observed heterozygosity (0.031). Most of the pairs of lines (78.36%) had Identity-by-State (IBS) based genetic distances of more than 0.3, indicating a significant amount of genetic diversity among the parental lines. Bayesian model-based population stratification, neighbor-joining phylogenetic analysis, and principal coordinate analysis (PCoA) differentiated all hybrid parental lines into two clear-cut major groups, one each for seed parents (B-lines) and pollinators (R-lines). Majority of parental lines sharing common parentages were found grouped in the same cluster. Analysis of molecular variance (AMOVA) revealed 7% of the variation among subpopulations, and 93% of the variation was attributable to within sub-populations. Chromosome 3 had the highest number of LD regions. Genomic LD decay distance was 0.69 Mb and varied across the different chromosomes. Genetic diversity based on 11 agro-morphological and grain quality traits also suggested that the majority of the B- and R-lines were grouped into two major clusters with few overlaps. In addition, the combined analysis of phenotypic and genotypic data showed similarities in the population grouping patterns. The present study revealed the uniqueness of most of the inbred lines, which can be a valuable source of new alleles and help breeders to utilize these inbred lines for the development of hybrids in drought-prone environments