Track-before-detect (TBD) algorithms incorporate unthresholded measurements to track targets under low signal-to-noise ratio (SNR) conditions. In this paper, we generalize a single target recursive ...TBD tracking algorithm to track a time-varying number of targets in low SNR and cluttered environments. This algorithm is important, for example, in tracking scenes involving multiple, closely spaced targets moving along the same direction such as a convoy of low observable vehicles moving through a forest, or multiple targets moving in a crisscross fashion. The proposed multi-mode, multi-target TBD (MM-MM-TBD) algorithm is based on estimating the probabilities of all possible combinations of target existence scenarios to obtain the joint multi-target posterior probability density function in a recursive Bayesian framework. We implement the algorithm recursively using particle filtering to also incorporate nonlinear/non-Gaussian tracking models. As the number of target existence combinations dynamically increases with the number of targets, we also propose an efficient proposal density function through partitioning of the multiple target space in order to decrease the number of particles and thus improve the approximation accuracy of the particle filter. We employ a heuristic decision-directed based approach to keep the computational complexity as a linear function of the maximum number of possible targets by exploiting the information obtained from the estimated mode probabilities.
Hydrogen (H2) is one of the most promising renewable energy sources, anaerobic bacterial H2 fermentation is considered as one of the most environmentally sustainable alternatives to meet the ...potential fossil fuel demand. Bio-H2 is the cleanest and most effective source of energy provided by the dark fermentation utilizing organic substrates and different wastewaters. In this study, the bio-H2 production was achieved by using the bacteria Acinetobacter junii-AH4. Further, optimization was carried out at different pH (5.0–8.0) in the presence of wastewaters as substrates (Rice mill wastewater (RMWW), Food wastewater (FWW) and Sugar wastewater (SWW). In this way, the optimized experiments excelled with the maximum cumulative H2 production of 566.44 ± 3.5 mL/L (100% FWW at pH 7.5) in the presence of Acinetobacter junii-AH4. To achieve this, a bioreactor (3 L) was employed for the effective production of H2 and Acinetobacter junii-AH4 has shown the highest cumulative H2 of 613.2 ± 3.0 mL/L, HPR of 8.5 ± 0.4 mL/L/h, HY of 1.8 ± 0.09 mol H2/mol glucose. Altogether, the present study showed a COD removal efficiency of 79.9 ± 3.5% by utilizing 100% food wastewater at pH 7.5. The modeled data established a batch fermentation system for sustainable H2 production. This study has aided to achieve an ecofriendly approach using specific wastewaters for the production of bio-H2.
•Acinetobacter junii-AH4 can be used for biohydrogen producing potential bacteria.•Two factors affecting biohydrogen production of Acinetobacter junii-AH4 were optimized.•In this study 3L bioreactor was employed for effective hydrogen production.•Maximum hydrogen yield of 1.8 ± 0.09 mol H2/mol glucose by utilizing 100% FWW at pH 7.5.
Bull fertility is of paramount importance in bovine industry because semen from a single bull is used to breed several thousands of cows; however, so far, no reliable test is available for bull ...fertility prediction. In the present study, spermatozoa from high- and low-fertility bulls were subjected to high-throughput transcriptomic, proteomic and metabolomic analysis. Using an integrated multi-omics approach the molecular differences between high- and low-fertility bulls were identified. We identified a total of 18,068 transcripts, 5041 proteins and 3704 metabolites in bull spermatozoa, of which the expression of 4766 transcripts, 785 proteins and 33 metabolites were dysregulated between high- and low-fertility bulls. At transcript level, several genes involved in oxidative phosphorylation pathway were found to be downregulated, while at protein level genes involved in metabolic pathways were significantly downregulated in low-fertility bulls. We found that metabolites involved in Taurine and hypotaurine metabolism were significantly downregulated in low-fertility bulls. Integrated multi-omics analysis revealed the interaction of dysregulated transcripts, proteins and metabolites in major metabolic pathways, including Butanoate metabolism, Glycolysis and gluconeogenesis, Methionine and cysteine metabolism, Phosphatidyl inositol phosphate, pyrimidine metabolism and saturated fatty acid beta oxidation. These findings collectively indicate that molecules governing sperm metabolism potentially influence bull fertility.
BACKGROUNDPerfluoroalkyl and poly-fluoroalkyl substances (PFAS) are pervasive environmental pollutants and emerging risk factors for reproductive health. Although epidemiological evidence supports ...the link between these substances and male infertility, their specific effects on male fertility remain poorly understood.OBJECTIVESInvestigate the effect of perfluorooctane sulfonic acid (PFOS), the most prevalent and prominent PFAS, on bull sperm protein phosphorylation, a post-translational modification process governing sperm functionality and fertility.METHODSWe exposed bull sperm to PFOS at 10 μM (average population level) and 100 μM (high-exposure level), and analyzed global proteome and phosphoproteome profile by TMT labeling and NanoLC-MS/MS. We also measured sperm fertility functions by flow cytometry.RESULTSPFOS at 10 μM altered sperm proteins linked to spermatogenesis and chromatin condensation, while at 100 μM, PFOS affected proteins associated with motility and fertility. We detected 299 phosphopeptides from 116 proteins, with 45 exhibiting differential expression between control and PFOS groups. PFOS dysregulated phosphorylation of key proteins (ACRBP, PRKAR2A, RAB2B, SPAG8, TUBB4B, ZPBP, and C2CD6) involved in sperm capacitation, acrosome reaction, sperm-egg interaction, and fertilization. PFOS also affected phosphorylation of other proteins (AQP7, HSBP9, IL4I1, PRKAR1A, and CCT8L2) related to sperm stress resistance and cryotolerance. Notably, 4 proteins (PRM1, ACRBP, TSSK1B, and CFAP45) exhibited differential regulation at both the proteomic and phosphoproteomic levels. Flow cytometric analysis confirmed that PFOS increased protein phosphorylation in sperm as well as reduced sperm motility, viability, calcium, and membrane potential and increased mitochondrial ROS in a dose-dependent manner.CONCLUSIONSThis study shows that PFOS exposure adversely impacts phosphorylation of proteins critical for bull sperm function and fertilization. Moreover, the concentration of PFOS influences the severity of these effects. The comprehensive bull sperm phosphoproteomics data from this study can help us understand the molecular mechanisms of environmental exposure-related male infertility.
Sperm harbours a wide range of proteins regulating their functions and fertility. In the present study, we made an effort to characterize and quantify the proteome of buffalo bull spermatozoa, and to ...identify fertility associated sperm proteins through comparative proteomics. Using high-throughput mass spectrometry platform, we identified 1305 proteins from buffalo spermatozoa and found that these proteins were mostly enriched in glycolytic process, mitochondrial respiratory chain, tricarboxylic acid cycle, protein folding, spermatogenesis, sperm motility and sperm binding to zona pellucida (p < 7.74E-08) besides metabolic (p = 4.42E-31) and reactive oxygen species (p = 1.81E-30) pathways. Differential proteomic analysis revealed that 844 proteins were commonly expressed in spermatozoa from both the groups while 77 and 52 proteins were exclusively expressed in high- and low-fertile bulls, respectively. In low-fertile bulls, 75 proteins were significantly (p < 0.05) upregulated and 176 proteins were significantly (p < 0.05) downregulated; these proteins were highly enriched in mitochondrial respiratory chain complex I assembly (p = 2.63E-07) and flagellated sperm motility (p = 7.02E-05) processes besides oxidative phosphorylation pathway (p = 6.61E-15). The down regulated proteins in low-fertile bulls were involved in sperm motility, metabolism, sperm-egg recognition and fertilization. These variations in the sperm proteome could be used as potential markers for the selection of buffalo bulls for fertility.
Although, it is well understood that sperm DNA damage is associated with infertility, the molecular details of how damaged sperm DNA affects fertility are not fully elucidated. Since sperm proteins ...play an important role in fertilization and post-fertilization events, the present study aimed to identify the sperm proteomic alterations in bulls with high sperm DNA Fragmentation Index (DFI%). Semen from Holstein-Friesian crossbred breeding bulls (n = 50) was subjected to Sperm Chromatin Structure Assay. Based on DFI%, bulls were classified into either high- (HDFI; n = 6), or low-DFI (LDFI; n = 6) and their spermatozoa were subjected to high throughput proteomic analysis. Liquid chromatography and mass spectrometry analysis identified 4567 proteins in bull spermatozoa. A total of 2660 proteins were found common to both the groups, while 1193 and 714 proteins were unique to HDFI and LDFI group, respectively. A total of 265 proteins were up regulated and 262 proteins were down regulated in HDFI group. It was found that proteins involved in capacitation heparin binding (molecular function), ERK1 and ERK2 cascade (biological process), PI3K-Akt signalling (pathway), Jak-STAT signalling (pathway), spermatogenesis TLR signalling (pathway), gamete generation (biological process) and DNA repair mechanism (biological process) were significantly altered in the bulls with high DFI%.
The reason for poor semen quality among the breeding bulls is not well understood. In the present study, we performed high‐throughput RNAseq analysis of spermatozoa to identify the SNPs present in ...good and poor‐quality semen‐producing Holstein Friesian breeding bulls. A total of 21,360 and 44,650 SNPs were identified in good and poor‐quality semen with a minimum read depth of 20, among which 4780 and 8710 novel variants were observed in good and poor‐quality semen, respectively. Greater SNPs and indels variations were observed in poor compared to good‐quality semen. In poor‐quality semen, SNP variations were observed in ZNF280B, SLC26A2, DMXL1, OR52A1, MACROD2 and REV1 genes, which are associated with regulation of spermatogenesis, post‐testicular maturation, Cl− channel activity, V‐ATPase‐mediated intracellular vesicle acidification, a mono‐ADP‐ribosyl hydrolase and ATR‐Chk1 checkpoint activation. GO analysis of filtered genes with significant variations between good and poor‐quality semen showed enrichment in important pathways related to semen quality such as MAPK signalling pathway, Akt signalling pathway, focal adhesion, cAMP signalling pathway, and Rap1 signalling pathway. Network analysis of filtered genes in poor‐quality semen showed variations in pathways of purine metabolism, pyrimidine metabolism, prolactin signalling pathway and RNA cap‐binding complex. It is inferred that SNP in genes involved in maintaining sperm functions could be the reason for poor‐quality semen production in bulls, and the identified SNPs hold potential to be used as biomarkers for semen quality in bulls.
Spermatozoa from high-fertile (HF) and low-fertile (LF) breeding bulls were subjected to high-throughput next-generation sequencing to identify important Single nucleotide polymorphisms (SNPs) and ...novel variants associated with fertility. A total of 77,038 genome-wide SNPs were identified, among which, 10,788 were novel variants. A total of 42,290 and 34,748 variants were recorded with 6115 and 4673 novel variants in in HF and LF bulls, respectively. Higher number of SNPs were identified in HF compared to LF bulls. GO analysis of filtered genes with significant variations in HF bulls indicated their involvement in oxidative phosphorylation and metabolic pathways. GO analysis of filtered genes with significant variation in LF bulls revealed their involvement in Ca
2++
ion binding, structural constituent of ribosome, and biological processes like translation and ribosomal small subunit assembly. The study identified SNPs in candidate genes including TPT1, BOLA-DRA, CD74, RPS17, RPS28, RPS29, RPL14, RPL13, and RPS27A, which are linked to sperm functionality, survival, oxidative stress, and bull fertility. The identified SNPs could be used in selection of bulls for high fertility and the variation in these genes could be established as an explanation for the fertility differences in bulls upon validation in large number of bulls.
The present study quantitatively characterized the proteomic changes in bull spermatozoa induced by the cryopreservation process. We performed high-throughput comparative global proteomic profiling ...of freshly ejaculated (before cryopreservation), equilibrated (refrigerated storage; during cryopreservation), and frozen (ultralow temperature; after cryopreservation) bull spermatozoa. Using the liquid chromatography-mass spectrometry (LC-MS/MS) technique, a total of 1,692, 1,415, and 1,286 proteins were identified in fresh, equilibrated, and cryopreserved spermatozoa, respectively. When the proteome of fresh spermatozoa was compared with equilibrated spermatozoa, we found that 166 proteins were differentially expressed. When equilibrated spermatozoa were compared with cryopreserved spermatozoa, we found that 147 proteins were differentially expressed between them. Similarly, we found that 156 proteins were differentially expressed between fresh and cryopreserved spermatozoa. Among these proteins, the abundance of 105 proteins was lowered during the equilibration process itself, while the abundance of 43 proteins was lowered during ultralow temperature preservation. Remarkably, the equilibration process lowered the abundance of sperm proteins involved in energy metabolism, structural integrity, and DNA repair and increased the abundance of proteins associated with proteolysis and protein degradation. The abundance of sperm proteins associated with metabolism, cGMP-PKG (cyclic guanosine 3',5'-monophosphate-dependent protein kinase G) signaling, and regulation of the actin cytoskeleton was also altered during the equilibration process. Collectively, the present study showed that the equilibration step in the bull sperm cryopreservation process was the critical point for sperm proteome, during which a majority of proteomic alterations in sperm occurred. These findings are valuable for developing efficient protocols to minimize protein damage and to improve the quality and fertility of cryopreserved bull spermatozoa.
We propose a method for estimating the space-time covariance matrix of rapidly-varying sea clutter following a dynamic state space matrix model. The covariance matrix dimension can become ...computationally infeasible as it increases with the number of range bins and dwell pulses required for coherent processing. In order to reduce the computational complexity, we apply the Kronecker product (KP) approximation and particle filtering to estimate the space-time covariance matrix, and we demonstrate the proposed method's validity using real clutter data. We also demonstrate that the method ensures that the covariance matrix estimate is always positive definite. The covariance matrix estimation is integrated with a track-before-detect filter for tracking a low radar cross-section (RCS) target in strong sea clutter.
