Acoustic emission signals analysis to differentiate the damage mechanism in the drilling of Al-5%B4C metal matrix composite.

Tool wear leads to dimensional inaccuracy and low surface quality in the workpiece, and unexpected sudden tool failure. Detection of tool wear is essential to enhance the quality of manufacturing components and extend tool life. The present work is aimed to investigate the various damage mechanisms involved in the cutting tool and workpiece during drilling of Al-5%B4C composite using acoustic emission technique (AET). The dry drilling experiments were carried out at different spindle speeds and feed rates with high strength steel (HSS) tool. AE time-domain parameters such as count, energy, amplitude and root mean square (RMS) voltage were extracted from the signals and correlated with cutting parameters and tool damage. Fast Fourier transform (FFT) was applied to visualize the frequency components in the AE signals during the drilling process. The wavelet packet transform (WPT) approach was performed to the AE signals to identify and discriminate the various damage mechanism involved in the drilling. The differentiated damage mechanism and their corresponding wavelet energy content were studied. The wavelet energy ratio for decomposed components at different speeds was discussed. The vision measuring microscope was employed to measure the tool wear. The AE features, i.e., AERMS and wavelet coefficient increases with increasing tool wear. A scanning electron microscope was also utilized to characterize the microstructural damage present in the cutting tool and workpiece.

Selective, Ultra-Sensitive, and Rapid Detection of Serotonin by Optimized ZnO Nanorod FET Biosensor.

BACKGROUND: Fluctuation in serotonin (5-HT) level is an essential manifestation of several neurological disorders. In view of such importance, it is necessary to monitor the levels of 5-HT with good sensitivity, selectivity, affordability and low response time. Zinc oxide (ZnO) based field effect transistors (FET) with attributes like minimized noise levels and large on-off ratio are regarded as emerging high performance biosensor platforms. However, their response is significantly non-linear and there has been no appreciable endeavor for improving the non-linearity. METHOD: In this paper, we have introduced embedded gate electrode encompassing the channel of the FET which improves the uniformity in electric field line distribution through the electrolyte and proportionately enhances the capture of target biomolecule at ultra-low concentrations, thereby increasing the linearity. Further, we have incorporated the optimized parameters of ZnO nanorods reported previously, for rapid and selective detection of 5-HT. RESULTS: It has been observed that the fabricated ZnO FET biosensor lowers the detection limit down to 0.1fM which is at least one order of magnitude lower than the existing reports. The sensor also has wide linear range from 0.1fM to 1nM with a detection time of about 20 minutes. CONCLUSION: The proposed zinc oxide nanorod-based sensor can be used as an excellent tool for future diagnosis of neurological disorders.

Development of in-bore magnetostrictive transducer for ultrasonic guided wave based-inspection of steam generator tubes of PFBR.

An in-bore magnetostrictive transducer is designed for the steam generator tubes of Prototype fast breeder reactor for the generation of L(0,2) modes of frequencies in the range of 250-350 kHz. Towards this, axi-symmetric finite element models are developed to optimize the coil parameters. The optimized length of the transmitter and the receiver coils turns out to be 10 mm (~half the wavelength) for the frequency of 300 kHz. The optimized width of the coils turns out to be 0.46 mm. FE models also show the generation, propagation and reception of L(0,2) modes in the frequency range of 250-350 kHz. The role of skin effect in the magnetostrictive based-generation of L(0,2) modes with frequency is also discussed. A transducer is designed based on the FE results. The transducer is tested for the generation of L(0,2) mode in the frequency range of 250-350 kHz in a 1 m long steam generator tube segment. A good agreement is observed between FE and experimental normalized amplitudes and the times of flight for different frequencies. L(0,2) modes are found to generate and propagate and received, as predicted by the finite element simulations. An excellent agreement is observed between the experimentally measured group velocities with those obtained from the dispersion curves in this frequency range. Experiments show the signal to noise ratio to be better than 15 dB. To ascertain the utility of the transducer in steam generator tubes for the long range testing, L(0,2) mode at 300 kHz frequency is propagated in a 1.5 m long tube. The resulted multiple end reflections amount to the propagation of 51 m distance. To check the capability of detection of defects, a short tube with a full circumferential defect of depth 0.46 mm (20%WT) and a short tube with a pin hole of 1.5 mm diameter are considered. Further, FE results for the case of the axi-symmetric circumferential defect are validated experimentally. For the case of the pinhole (non-axi-symmetric), the experimental signal to noise ratio turns out to be 6 dB, which is only 6 dB lower as compared to that obtained using a piezo based ultrasonic transducer of frequency 300 kHz coupled to the end of the tube.

Variations in antibiotic use across India: multi-centre study through Global Point Prevalence survey.

The aim of the study was to assess antimicrobial prescribing patterns, and variation in practice, in India. A point prevalence survey (PPS) was conducted in October to December 2017 in 16 tertiary care hospitals across India. The survey included all inpatients receiving an antimicrobial on the day of PPS and collected data were analysed using a web-based application of the University of Antwerp. In all, 1750 patients were surveyed, of whom 1005 were receiving a total of 1578 antimicrobials. Among the antimicrobials prescribed, 26.87% were for community-acquired infections; 19.20% for hospital-acquired infections; 17.24% for medical prophylaxis; 28.70% for surgical prophylaxis; and 7.99% for other or undetermined reasons. Antibiotic prescribing quality indicators, such as reason in notes and post-prescription review score, were low. This PPS showed widespread antibiotic usage, underlining the need for antibiotic stewardship to promote evidence-based practice.

Diagnostic utility of in-house loop-mediated isothermal amplification and real-time PCR targeting virB gene for direct detection of Brucella melitensis from clinical specimens.

AIMS: In this present study, the utility of a newly developed loop-mediated isothermal amplification (LAMP) and real-time PCR assays designed to amplify the virB gene region of Brucella melitensis was evaluated from human clinical specimens. METHODS AND RESULTS: Fifty-four culture-confirmed cases of brucellosis and 54 culture negative but clinically suspected cases of brucellosis were included in the study. Whole blood, serum and other nonblood specimens were collected and subjected to blood culture using automatic blood culture system, serological tests, LAMP assay and real-time PCR. Overall sensitivities of LAMP and real-time PCR assays were 67·5 and 68·3% respectively. For nonblood clinical specimens, we noticed a marked increase in the sensitivities of LAMP (88·9%) and real-time PCR (100%) assays. CONCLUSIONS: Performance of LAMP and real-time PCR was not satisfactory for whole-blood specimens because of the low abundance of bacteria or DNA. On the other hand, using nonblood specimens, both the assays showed higher sensitivity and specificity which makes them a good alternative for the rapid diagnosis of human brucellosis. SIGNIFICANCE AND IMPACT OF THE STUDY: The developed LAMP and real-time PCR assays are a specific and rapid diagnostic tool for direct and early detection of Brucella in clinical specimens.

Development of ultrasonic guided wave inspection methodology for steam generator tubes of prototype fast breeder reactor.

An ultrasonic guided wave based methodology is developed for inspection of steam generator tubes of the prototype fast breeder reactor. To this aim, axisymmetric longitudinal mode (L(0,2)) at the frequency of 250 kHz is optimized using 3D-finite element simulation and experiments. The group velocity of mode L(0,2) at 250 kHz is found to be 5387 m/s. First, the long range propagation of the L(0,2) mode at 250 kHz is examined and the mode is found to propagate over a distance of 45.6 m with a sufficiently good SNR. Secondly, the detection of multiple defects such as circumferential, axial, partial-pinholes and tapered defects lying in the same line of sight is investigated using 3D-finite element simulation and the results obtained are validated experimentally for the first three cases. The sensitivities achieved are 0.23 mm depth (10%WT) for circumferential, axial and tapered defects and for partial-pinholes: 1 mm diameter and 1.38 mm depth (60%WT). Thirdly, 3D-FE simulations with ID and OD pinhole defects are performed which show that the ID and OD defects are detected by L(0,2) with a fairly similar sensitivity. Finally, study on the thermal expansion bend (with three successive bends) shows that the bend does not have much influence on the mode and the multiple circumferential defects considered in the bend are detected with good sensitivity.

Deciphering the transcriptome of prepubertal buffalo mammary glands using RNA sequencing.

Although water buffaloes are the main milk-producing animals in Indian subcontinent, only limited attempts have been made to identify canonical pathways and gene regulatory networks operating within the mammary glands of these animals. Such information is important for identifying unique transcriptome signatures in the mammary glands of diseased animals. In this report, we analyzed the transcription profile of 3 prepubertal buffalo mammary glands and identified common genes (mean FPKM > 0.2 in all samples) operating in the glands. Among 19,994 protein coding genes, 14,678 genes expressed and 5316 unique genes did not express in prepubertal buffalo mammary glands. Of these 14,678 expressed genes, 79% comprised a ubiquitous transcriptome that was dominated by very lowly expressed genes (51%). The percentage of rarely, moderately, and abundantly expressed genes was 25%, 2%, and 1%, respectively. Gene Ontology (GO) terms reflected in the expression of common genes (mean FPKM > 5.0) for molecular function were related to binding and catalytic activity. Products of these genes were involved in metabolic and cellular processes and belong to nucleic acid binding proteins. The canonical pathways for growth of mammary glands included integrin signaling, inflammation, GnRH and Wnt pathways. KEGG enriched pathways revealed many pathways of cancer including ribosome, splisosome, endocytosis, and ubiquitin-mediated proteolysis, pathways for viral infection, and bacterial invasion of epithelial. Highly expressed genes (mean FPKM > 500 included beta-actin (ACTB), beta-2 microglobulin (B2M), caseins (CSN2, CNS3), collagens (COL1A1, COL3A1), translation elongation factors (EEF1A1, EEF1G, EEF2), keratins (KRT15, KRT19), major histocompatibility complex genes (CD74, JSP.1), vimentin (VIM), and osteopontin (SPP1). Interestingly, expression of milk protein genes in prepubertal glands opens possible roles of these genes in development of mammary glands. We report the whole transcriptomic signature of prepubertal buffalo mammary gland and indicated its molecular signature is similar to cancer type.

Examination of the xanthosine response on gene expression of mammary epithelial cells using RNA-seq technology.

BACKGROUND: Xanthosine treatment has been previously reported to increase mammary stem cell population and milk production in cattle and goats. However, the underlying molecular mechanisms associated with the increase in stem cell population and milk production remain unclear. METHODS: Primiparous Beetal goats were assigned to the study. Five days post-partum, one mammary gland of each goat was infused with xanthosine (TRT) twice daily (2×) for 3 days consecutively, and the other gland served as a control (CON). Milk samples from the TRT and CON glands were collected on the 10th day after the last xanthosine infusion and the total RNA was isolated from milk fat globules (MEGs). Total RNA in MFGs was mainly derived from the milk epithelial cells (MECs) as evidenced by expression of milk synthesis genes. Significant differentially expressed genes (DEGs) were subjected to Gene Ontology (GO) terms using PANTHER and gene networks were generated using STRING db. RESULTS: Preliminary analysis indicated that each individual goat responded to xanthosine treatment differently, with this trend being correlated with specific DEGs within the same animal's mammary gland. Several pathways are impacted by these DEGs, including cell communication, cell proliferation and anti-microbials. CONCLUSIONS: This study provides valuable insights into transcriptomic changes in milk producing epithelial cells in response to xanthosine treatment. Further characterization of DEGs identified in this study is likely to delineate the molecular mechanisms of increased milk production and stem or progenitor cell population by the xanthosine treatment.

Validation of immunomodulatory effects of lipopolysaccharide through expression profiling of Th1 and Th2 biased genes in Newcastle disease virus vaccinated indigenous chicken.

BACKGROUND AND AIM: Newcastle disease (ND) is considered one of the most important poultry diseases with chicken morbidity and mortality rates up to 100%. Current vaccination programs allow the use of live attenuated vaccines in the field to protect against the disease, which alone is inefficient and requires repeat booster doses. Toll-like receptor agonists (e.g., lipopolysaccharide [LPS]) as adjuvants are the ones, most extensively studied and have shown to be very promising in delivering a robust balanced immune response. In the present study, we have evaluated the potential of LPS to elicit a strong immune response with respect to the elicitation of both Th1 (cell-mediated) and Th2 (humoral) immune arms. MATERIALS AND METHODS: A total of 72 apparently healthy 1-day-old indigenous unvaccinated chicks were randomly divided into six experimental Groups A to F (n=12). At 8-week of age chicks in Group A, C, and E were vaccinated with live attenuated La Sota strain ND vaccine along with LPS, bovine serum albumin, and normal saline solution, respectively, and those in Group B, D, and E were kept separately without vaccination. Sampling was done on days 0, 1, 3, 7, 14, 21, 35, and 60 after vaccination. After vaccination and respective adjuvant application, Th1 and Th2 cytokine expression were measured in mRNA of both blood and tissue samples. RESULTS: The results were validated by, hemagglutination inhibition and enzyme-linked immunosorbent assay tests, to check for the humoral as well as cell-mediated immune response in blood serum levels. The results showed an increase in mRNA expression of the Th1 biased cytokines in Group A (LPS+NDV) as compared to the control groups. Similar mRNA expression pattern was seen in blood as well as tissue samples. Validation of results also indicates an increase in Cell-mediated Immunity as well as a humoral immune response in Group A (LPS+NDV). CONCLUSION: The results of the study provided enough evidence to consider LPS as a potential vaccine adjuvants candidate against ND in chicken.

Microvesicles in hepatic and peripheral vein can predict nonresponse to corticosteroid therapy in severe alcoholic hepatitis.

BACKGROUND: Severe alcoholic hepatitis patients have high mortality and limited response to corticosteroids. Microvesicles reflect cellular stress and disease conditions. AIMS: To investigate whether microvesicles are associated with severity, response to steroid therapy and inflammation in severe alcoholic hepatitis. METHODS: Microvesicles originating from different cells were studied pre-therapy in 101 patients; (71 responder to corticosteroid therapy and 30 nonresponders) and 20 healthy controls. Microvesicles and cells were determined in peripheral and hepatic vein samples using flow cytometry and correlated with outcomes. Inflammatory signalling pathways and functional alterations of immune cells after stimulation with microvesicles were also investigated. RESULTS: Microvesicles mean levels were higher in nonresponders for T cells (CD3+ CD4+ ; 10.1 MV/µL vs 5.4; P = 0.06), macrophages (CD68+ CD11b+ ; 136.5 vs 121.9 MV/µL; P = 0.01), haematopoietic stem-cells (CD45+ CD34+ ; 116.8 vs 13.4 MV/µL; P = 0.0001) and hepatocytes (ASGPR+ ; 470 vs 361 MV/µL; P = 0.01); the latter two predicting steroid nonresponse in 94% patients at baseline in peripheral plasma. Microvesicle levels correlated with histological and liver disease severity indices. Whereas, in non-responders hepatic vein CD34+ cells were lower (P = 0.02), the CD34+ microvesicles there from were higher (P = 0.04), thus suggesting impaired regeneration. Also, microvesicles of 0.2-0.4 µm size were higher in nonresponders (P < 0.03) at baseline. Microvesicles from patients trigger more (P = 0.04) ROS generation, TNF-α production (P = 0.04) and up-regulate pro-inflammatory cytokine related genes in neutrophils in vitro. CONCLUSIONS: Pre-therapy peripheral plasma levels of CD34+ and ASGPR+ microvesicles are reliable non-invasive markers of steroid nonresponse and mortality in patients with severe alcoholic hepatitis.

Biocomputational identification and validation of novel microRNAs predicted from bubaline whole genome shotgun sequences.

MicroRNAs (miRNAs) are small (19-25 base long), non-coding RNAs that regulate post-transcriptional gene expression by cleaving targeted mRNAs in several eukaryotes. The miRNAs play vital roles in multiple biological and metabolic processes, including developmental timing, signal transduction, cell maintenance and differentiation, diseases and cancers. Experimental identification of microRNAs is expensive and lab-intensive. Alternatively, computational approaches for predicting putative miRNAs from genomic or exomic sequences rely on features of miRNAs viz. secondary structures, sequence conservation, minimum free energy index (MFEI) etc. To date, not a single miRNA has been identified in bubaline (Bubalus bubalis), which is an economically important livestock. The present study aims at predicting the putative miRNAs of buffalo using comparative computational approach from buffalo whole genome shotgun sequencing data (INSDC: AWWX00000000.1). The sequences were blasted against the known mammalian miRNA. The obtained miRNAs were then passed through a series of filtration criteria to obtain the set of predicted (putative and novel) bubaline miRNA. Eight miRNAs were selected based on lowest E-value and validated by real time PCR (SYBR green chemistry) using RNU6 as endogenous control. The results from different trails of real time PCR shows that out of selected 8 miRNAs, only 2 (hsa-miR-1277-5p; bta-miR-2285b) are not expressed in bubaline PBMCs. The potential target genes based on their sequence complementarities were then predicted using miRanda. This work is the first report on prediction of bubaline miRNA from whole genome sequencing data followed by experimental validation. The finding could pave the way to future studies in economically important traits in buffalo.

Cellular thermotolerance is independent of HSF 1 expression in zebu and crossbred non-lactating cattle.

Heat stress is an important domain of research in livestock due to its negative impact on production and disease resistance. The augmentation of stress in the body stimulates the antioxidative activity comprising various enzymes (viz., catalase, superoxide dismutase), metabolites (reduced glutathione, etc.), vitamins, minerals, etc. to combat the situation. The major key players involved in regulation of heat shock response in eukaryotes are the transcription factors, called as heat shock factors (HSF). They activate the heat shock protein (HSP) genes by binding to their promoters. Lymphocytes are considered to be the best model to evaluate the immunity in any living body as it contains plethora of white blood cells (WBCs).In this study, the peripheral blood mononuclear cells (PBMC) obtained from non-lactating Sahiwal vis-à-vis crossbred (Holstein Friesian × Sahiwal) cattle with 75% or more exotic inheritance were subjected to heat shock at 39, 41, and 43 °C in three different incubators, in vitro. The cell count and viability test of pre and post heat stress of concerned PBMCs indicated that the crossbreeds are more prone to heat stress as compared to Sahiwal. The reverse transcription PCR (qRT-PCR) expression data revealed an increment in HSF1 expression at 41 °C which subsequently declined (non-significantly) at 43 °C in both breeds post 1 h heat shock. However, the association between the HSF 1 expression and antioxidative activity through correlation analysis was found to be non-significant (P < 0.05), though enzymatic activity appeared to behave in a similar fashion in both breeds at 5% level of significance (P < 0.05). This rule out the role of HSF1 expression level on the activity of enzymes involved in oxidative stress in vitro in zebu and crossbred cattle.

Chronic exposure to indoxacarb and pulmonary expression of toll-like receptor-9 in mice.

AIM: Chronic exposure to indoxacarb and pulmonary expression of toll-like receptor 9 (TLR-9) in mice. MATERIALS AND METHODS: In this study, healthy male Swiss albino mice (n=30) aging 8-10 weeks were used to evaluate TLR-9 expression in lungs of mice following indoxacarb exposure with and without lipopolysaccharide (LPS). Indoxacarb was administered orally dissolved in groundnut oil at 4 and 2 mg/kg/day for 90 days. On day 91, five animals from each group were challenged with LPS/normal saline solution at 80 µg/animal. The lung tissues were processed for real time and immunohistochemical studies. RESULTS: LPS resulted increase in fold change m-RNA expression level of TLR-9 as compare to control, while indoxacarb (4 mg/kg) alone and in combination with LPS resulted 16.21-fold change and 29.4-fold change increase in expression of TLR-9 m-RNA, respectively, as compared to control. Similarly, indoxacarb (2 mg/kg) alone or in combination with LPS also altered TLR-9 expression. Further at protein level control group showed minimal expression of TLR-9 in lungs as compare to other groups, however, LPS group showed intense positive staining in bronchial epithelium as well as in alveolar septal cells. Indoxacarb at both doses individually showed strong immuno-positive reaction as compare to control, however when combined with LPS resulted intense staining in airway epithelium as compare to control. CONCLUSION: Chronic oral administration of indoxacarb for 90 days (4 and 2 mg/kg) alters expression of TLR-9 at m-RNA and protein level and co-exposure with LPS exhibited synergistic effect.

The antibiotics of choice for the treatment of melioidosis in Indian set up.

Therapeutic options for the treatment of melioidosis caused by Burkholderia pseudomallei are limited due to the inherent resistance conferred by this pathogen to various groups of antibiotics. Witnessing an increase in the number of microbiological culture-confirmed cases of melioidosis at our settings in the past few years, we undertook this study to estimate the minimum inhibitory concentrations of clinical isolates of B. pseudomallei against the four commonly employed antimicrobial agents in the patient management at our settings, namely, ceftazidime, meropenem, trimethoprim-sulfamethoxazole and doxycycline. All isolates were susceptible to the antibiotics tested, except for one isolate which showed resistance to doxycycline (minimum inhibitory concentration [MIC]: 32 µg/ml). MIC50 and 90 for all the four antibiotics were estimated. From this study, we conclude that the clinical isolates of B. pseudomallei from the southern part of India are well susceptible to the commonly employed antimicrobial agents for therapy.

A rare glimpse into the morbid world of necrotising fasciitis: Flesh-eating bacteria Vibrio vulnificus.

Necrotising fasciitis is one of the fatal skin and soft tissue infections. Vibrio vulnificus is a rare cause of necrotising fasciitis; however, the disease is one of the major manifestations of the bacteria. Here, we report one such case in a middle-aged male patient. He presented with the signs of bilateral lower limb cellulitis and altered sensorium. V. vulnificus was isolated from blood culture and also from debrided tissue. Though the organism is well characterised, it is a rare causative agent of necrotising fasciitis. This case is a re-emphasis on active look out for this bacterium in patients presenting with necrotizsing fasciitis.

Identification of the MicroRNA Repertoire in TLR-Ligand Challenged Bubaline PBMCs as a Model of Bacterial and Viral Infection.

In the present study, we used high-throughput sequencing, miRNA-seq, to discover and explore the expression profiles of known and novel miRNAs in TLR ligand-stimulated vis-à-vis non-stimulated (i.e. Control) peripheral blood mononuclear cells (PBMCs) isolated from blood of healthy Murrah buffaloes. Six small RNA (sRNA) libraries were multiplexed in Ion Torrent PI chip and sequenced on Ion Proton System. The reads obtained were aligned to the Bos taurus genome (UMD3.1 assembly), which is phylogenetically closest species to buffalo (Bubalus bubalis). A total of 160 bovine miRNAs were biocomputationally identified in buffalo PBMCs and 130 putatively novel miRNAs (not enlisted in the bovine mirBase) were identified. All of these 290 miRNAs identified across the six treatment and control samples represent the repertoire of novel miRNAs for the buffalo species. The expression profiles of these miRNAs across the samples have been represented by sample dendrogram and heatmap plots. The uniquely expressed miRNAs in each treatment and control groups were identified. A few miRNAs were expressed at very high levels while the majority of them were moderately expressed. The miRNAs bta-miR-103 and -191 were found to be highly abundant and expressed in all the samples. Other abundantly expressed miRNAs include bta-miR-19b, -29b, -15a, -19a, -30d, -30b-5p and members of let family (let 7a-5p, let 7g & let 7f) in LPS and CpG treated PBMCS and bta-miR-191, -103 & -19b in Poly I:C stimulated PBMCs. Only one novel miRNA (bta-miR-11039) out of 130 identified putatively novel miRNAs, was expressed in all the six samples and differentially expressed (>2- fold) miRNAs were identified. Six of the differentially expressed miRNAs across the groups (bta-miR-421, bta-let-7i, bta-miR-138, bta-miR-21-5p, bta-miR-222 and bta-miR-27b) were subsequently confirmed by TaqMan quantitative reverse transcription polymerase chain reaction (qRT-PCR). Furthermore, the target genes of differentially expressed miRNAs were enriched for the roles in innate immunity and TLR signaling pathways. This maiden study on profiling and cataloguing of bubaline miRNAs expressed in TLR-ligand stimulated PBMCs will provide an important reference point for future studies on regulatory roles of miRNAs in immune system of buffaloes.