An automated system of intrusion detection by IoT-aided MQTT using improved heuristic-aided autoencoder and LSTM-based Deep Belief Network.

The IoT offered an enormous number of services with the help of multiple applications so it faces various security-related problems and also heavy malicious attacks. Initially, the IoT data are gathered from the standard dataset as Message Queuing Telemetry Transport (MQTT) set. Further, the collected data are undergone the pre-processing stage, which is accomplished by using data cleaning and data transformation. The resultant processed data is given into two models named (i) Autoencoder with Deep Belief Network (DBN), in which the optimal features are selected from Autoencoder with the aid of Modified Archimedes Optimization Algorithm (MAOA). Further, the optimal features are subjected to the AL-DBN model, where the first classified outcomes are obtained with the parameter optimization of MAOA. Similarly, (ii) Long Short-Term Memory (LSTM) with DBN, in this model, the optimal features are chosen from LSTM with the aid of MAOA. Consequently, the optimal features are subjected into the AL-DBN model, where the second classified outcomes are acquired. Finally, the average score is estimated by two outcomes to provide the final classified result. Thus, the findings reveal that the suggested system achieves outstanding results to detect the attack significantly.

A review of immune modulators and immunotherapy in infectious diseases.

The human immune system responds to harmful foreign invaders frequently encountered by the body and employs defense mechanisms to counteract such assaults. Various exogenous and endogenous factors play a prominent role in maintaining the balanced functioning of the immune system, which can result in immune suppression or immune stimulation. With the advent of different immune-modulatory agents, immune responses can be modulated or regulated to control infections and other health effects. Literature provides evidence on various immunomodulators from different sources and their role in modulating immune responses. Due to the limited efficacy of current drugs and the rise in drug resistance, there is a growing need for new therapies for infectious diseases. In this review, we aim to provide a comprehensive overview of different immune-modulating agents and immune therapies specifically focused on viral infectious diseases.

Miscibility, thermal degradation and rheological analysis of epoxy/MABS blends.

The effect of the addition of the methyl methacrylate acrylonitrile butadiene styrene (MABS) copolymer on the miscibility, thermal degradation and rheological properties of epoxy systems is described. Epoxy resin/MABS blends containing 5, 10, 15 and 20 phr MABS were prepared using the solution mixing technique. Homogenous blends obtained using this technique have undergone a polymerization reaction induced phase separation process by the introduction of the curing agent 4,4'-diaminodiphenyl sulfone (DDS). The isothermal rheology at four different temperatures, 150, 160, 170 and 180 °C, was used to examine the effect of MABS on the gelation and vitrification time. The evolution of storage modulus, loss modulus and tan delta was found to be closely related to the evolution of complex phase separation. The increase in the complex viscosity during curing was determined by in situ rheometry and theoretically analysed by fitting with the Williams-Landell-Ferry equation. An exponential increase in complex viscosity was observed, which was induced by cross-linking. The variation of Tg before and after curing was studied using DSC analysis and dynamic kinetic modeling of the curing process was carried out by utilizing dynamic DSC scans. Thermal stability studies of completely cured epoxy/MABS blends using thermogravimetric analysis revealed that all the blends and neat epoxy exhibited single step degradation. Thermal degradation kinetics was calculated using the Coats Redfern equation.

Chlorine-free extraction and structural characterization of cellulose nanofibers from waste husk of millet (Pennisetum glaucum).

This study aims to extract cellulose nanofibers (CNFs) from a sustainable source, i.e. millet husk, which is an agro-waste worthy of consideration. Pre-treatments such as mercerisation, steam explosion, and peroxide bleaching (chlorine-free) were applied for the removal of non-cellulosic components. The bleached millet husk pulp was subjected to acid hydrolysis (5% oxalic acid) followed by homogenization to extract CNFs. The extracted CNFs were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Dynamic Light Scattering (DLS), Energy Dispersive X-ray Spectroscopy (EDX), Thermogravimetry (TG and DTG), Differential scanning calorimetry (DSC), and Solid state 13C nuclear magnetic resonance spectroscopy (solid state 13C NMR). The isolated CNFs show a typical cellulose type-I structure with a diameter of 10-12 nm and a crystallinity index of 58.5%. The appearance of the specific peak at 89.31 ppm in the solid state 13C NMR spectra validates the existence of the type-I cellulose phase in the prepared CNFs. The prepared CNFs had a maximum degradation temperature (Tmax) of 341 °C, that was 31 °C greater than raw millet husk (RMH). The outcome of the study implies that the nanofibers are prominent alternatives for synthetic fibers for assorted potential applications, especially in manufacturing green composites.

Nanocoatings: Universal antiviral surface solution against COVID-19.

In the current scenario, there is critical global demand for the protection of daily handling surfaces from the viral contamination to limit the spread of COVID-19 infection. The nanotechnologists and material scientists offer sustainable solutions to develop antiviral surface coatings for various substrates including fabrics, plastics, metal, wood, food stuffs etc. to face current pandemic period. They create or propose antiviral surfaces by coating them with nanomaterials which interact with the spike protein of SARS-CoV-2 to inhibit the viral entry to the host cell. Such nanomaterials involve metal/metal oxide nanoparticles, hierarchical metal/metal oxide nanostructures, electrospun polymer nanofibers, graphene nanosheets, chitosan nanoparticles, curcumin nanoparticles, etched nanostructures etc. The antiviral mechanism involves the repletion (depletion) of the spike glycoprotein that anchors to surfaces by the nanocoating and makes the spike glycoprotein and viral nucleotides inactive. The nature of interaction between the nanomaterial and virus depends on the type nanostructure coating over the surface. It was found that functional coating materials can be developed using nanomaterials as their polymer nanocomposites. The various aspects of antiviral nanocoatings including the mechanism of interaction with the Corona Virus, the different type of nanocoatings developed for various substrates, future research areas, new opportunities and challenges are reviewed in this article.

Flexible Pressure Sensor Based on PVDF Nanocomposites Containing Reduced Graphene Oxide-Titania Hybrid Nanolayers.

A novel flexible nanocomposite pressure sensor with a tensile strength of about 47 MPa is fabricated in this work. Nanolayers of titanium dioxide (titania nanolayers, TNL) synthesized by hydrothermal method are used to reinforce the polyvinylidene fluoride (PVDF) by simple solution mixing. A hybrid composite is prepared by incorporating the TNL (2.5 wt %) with reduced graphene oxide (rGO) (2.5 wt %) synthesized by improved graphene oxide synthesis to form a PVDF/rGO-TNL composite. A comparison between PVDF, PVDF/rGO (5 wt %), PVDF/TNL (5 wt %) and PVDF/rGO-TNL (total additives 5 wt %) samples are analyzed for their sensing, thermal and dielectric characteristics. The new shape of additives (with sharp morphology), good interaction and well distributed hybrid additives in the matrix increased the sensitivity by 333.46% at 5 kPa, 200.7% at 10.7 kPa and 246.7% at 17.6 kPa compared to the individual PVDF composite of TNL, confirming its possible application in fabricating low cost and light weight pressure sensing devices and electronic devices with reduced quantity of metal oxides. Increase in the ß crystallinity percentage and removal of α phase for PVDF was detected for the hybrid composite and linked to the improvement in the mechanical properties. Tensile strength for the hybrid composite (46.91 MPa) was 115% higher than that of the neat polymer matrix. Improvement in the wettability and less roughness in the hybrid composites were observed, which can prevent fouling, a major disadvantage in many sensor applications.

TiO2 nanotubes and mesoporous silica as containers in self-healing epoxy coatings.

The potential of inorganic nanomaterials as reservoirs for healing agents is presented here. Mesoporous silica (SBA-15) and TiO2 nanotubes (TNTs) were synthesized. Both epoxy-encapsulated TiO2 nanotubes and amine-immobilized mesoporous silica were incorporated into epoxy and subsequently coated on a carbon steel substrate. The encapsulated TiO2 nanotubes was quantitatively estimated using a 'dead pore ratio' calculation. The morphology of the composite coating was studied in detail using transmission electron microscopic (TEM) analysis. The self-healing ability of the coating was monitored using electrochemical impedance spectroscopy (EIS); the coating recovered 57% of its anticorrosive property in 5 days. The self-healing of the scratch on the coating was monitored using Scanning Electron Microscopy (SEM). The results confirmed that the epoxy pre-polymer was slowly released into the crack. The released epoxy pre-polymer came into contact with the amine immobilized in mesoporous silica and cross-linked to heal the scratch.

Copper oxide nanoparticles in an epoxy network: microstructure, chain confinement and mechanical behaviour.

Copper oxide nanoparticles (nCOPs) having octahedral morphology, synthesized through hydrazine reduction reaction were employed to formulate an epoxy based novel nanocomposite. The synthesis of copper oxide nanoparticles was carried out in polyethylene glycol medium to enhance their interfacial adhesion with the epoxy matrix. The extent of conservation of the crystalline nature and octahedral morphology of the nCOP in its epoxy nanocomposites was confirmed by X-ray diffraction and electron microscopy analysis. The mechanical properties including tensile, impact, fracture toughness and surface hardness of epoxy-nCOP nanocomposites were evaluated as a function of nCOP content. The maximum enhancement in strength, modulus, impact strength, fracture toughness and surface hardness of epoxy-nCOP nanocomposites was observed for 5 phr nCOP content. This may be due to the strong interaction between the nCOP and epoxy chains at this composition arising from its fairly uniform dispersion. A quantitative measurement of constrained epoxy chains immobilized by the nCOP octahedra was carried out using dynamic mechanical analysis. The enhancement in the storage modulus is related to the amount of the added nCOP as well as the volume of the constrained epoxy chains in the proximity of nCOP. The behaviour of epoxy-nCOP nanocomposites in this study has been explained by proposing a mechanism based on the distribution of nCOP domains in the epoxy matrix and the existing volume of constrained epoxy chains.

Biochemical and histopathological responses of the Swiss albino mice treated with uranyl nitrate and its recovery.

Uranium is a radioactive heavy metal ubiquitous in the natural environment. In its chemical form, it is known to induce nephrotoxicity both in human and in animals. Its toxicity is dose and time dependent, also varies with form of uranium. In the present study, we assessed the nephrotoxicity induced by a single dose of uranyl nitrate (UN) in mice at different time intervals and recovery from its toxicity. Two doses of 2 and 4 mg/kg body weight of uranyl nitrate was injected intraperitoneally and animals were sacrificed after 1, 3, 5, 14, and 28 d of administration. Histopathological and biochemical alterations of post-UN dosing in comparison to control were evaluated. Tubular damage to about 75% was observed after 3 d (4 mg/kg) and the biochemical parameters such as serum creatinine, urea, and blood urea nitrogen levels were also significantly increased. Progression of tubular damage was not found after 5 d. Dose-dependent recovery of uranyl nitrate-treated animals was observed after 14 and 28 d of dosing. The concentration of uranium retained in kidney correlates with biochemical and histopathological analysis.

Volume shrinkage and rheological studies of epoxidised and unepoxidised poly(styrene-block-butadiene-block-styrene) triblock copolymer modified epoxy resin-diamino diphenyl methane nanostructured blend systems.

Styrene-block-butadiene-block-styrene (SBS) copolymers epoxidised at different epoxidation degrees were used as modifiers for diglycidyl ether of the bisphenol A-diamino diphenyl methane (DGEBA-DDM) system. Epoxy systems containing modified epoxidised styrene-block-butadiene-block-styrene (eSBS) triblock copolymer with compositions ranging from 0 to 30 wt% were prepared and the curing reaction was monitored in situ using rheometry and pressure-volume-temperature (PVT) analysis. By controlling the mole percent of epoxidation, we could generate vesicles, worm-like micelles and core-shell nanodomains. At the highest mole percent of epoxidation, the fraction of the epoxy miscible component in the triblock copolymer (epoxidised polybutadiene (PB)) was maximum. This gave rise to core-shell nanodomains having a size of 10-15 nm, in which the incompatible polystyrene (PS) becomes the core, the unepoxidised PB becomes the shell and the epoxidised PB interpenetrates with the epoxy phase. On the other hand, the low level of epoxidation gave rise to bigger domains having a size of ∼1 µm and the intermediate epoxidation level resulted in a worm-like structure. This investigation specifically focused on the importance of cure rheology on nanostructure formation, using rheometry. The reaction induced phase separation of the PS phase in the epoxy matrix was carefully explored through rheological measurements. PVT measurements during curing were carried out to understand the volume shrinkage of the blend, confirming that shrinkage behaviour is related to the block copolymer phase separation process during curing. The volume shrinkage was found to be maximum in the case of blends with unmodified SBS, where a heterogeneous morphology was observed, while a decrease in the shrinkage was evidenced in the case of SBS epoxidation. It could be explained by two effects: (1) solubility of the epoxidised block copolymer in the DGEBA leads to the formation of nanoscopic domains upon reaction induced phase separation and (2) the plasticisation effect of the epoxidised block copolymer in the epoxy resin.

Subthreshold micropulse yellow laser (577 nm) in chronic central serous chorioretinopathy: safety profile and treatment outcome.

PURPOSE: To assess the safety and efficacy of a single session of subthreshold micropulse (SM) yellow laser (577 nm) in the treatment of chronic central serous chorioretinopathy (CSCR). METHODS: This was a retrospective analysis of 15 eyes of 13 patients with CSCR of >3 months duration who had been treated with SM yellow laser (577 nm). All patients had been treated using multiple spots of laser with a duty cycle of 10% over areas of focal and diffuse leak, as seen on fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA). Reduction in subretinal fluid height on spectral domain optical coherence tomography (SD-OCT) was used to measure the response to treatment. RESULTS: The mean follow-up was at 8 weeks (4-19 weeks). All eyes responded to treatment. The mean subretinal fluid height pre and post treatment was 232 and 49 µm, respectively, showing a 79% average reduction (P<0.001) in fluid height. There was no evidence of retinal pigment epithelium or retinal damage on SD-OCT, FFA, or fundus autofluorescence. Median visual improvement was one line on Snellen's visual acuity chart (P=0.015). Microperimetry was performed in eight eyes of which six eyes (75%) showed an improvement in the threshold values post treatment. CONCLUSION: SM yellow laser is an effective treatment option for chronic CSCR.

Capturing cold-stress-related sequence diversity from a wild relative of common bean (Phaseolus angustissimus).

One restriction to the cultivation of common bean, Phaseolus vulgaris L., is its limited tolerance to low temperatures. In the present study, subtraction suppression hybridization was employed to enrich for stress responsive genes in both a chilling-susceptible common bean and a relatively more chilling-tolerant wild bean species, Phaseolus angustissimus. For each species, approximately 11 000 expressed sequence tags were generated. Comparative sequence analysis of the EST collection with the available annotated genome sequences of the model Fabaceae species Medicago truncatula and Glycine max identified protein homologues for approximately 65% and 80% of the Phaseolus sequences, respectively. This difference reflects the closer phylogenetic relationship between the genera Phaseolus and Glycine compared with Medicago. Annotation of the Phaseolus sequences was facilitated through this comparative analysis and indicated that several heat shock proteins, cytochrome P450s, and DNA binding factors were uniquely found among the sequences from the wild species P. angustissimus. The Phaseolus sequences have been made available on a GBrowse implementation using M. truncatula as the reference genome, providing rapid access to the sequence data and associated comparative genome data.

Estimation of biological half-life of tritium in coastal region of India.

The present study estimates biological half-life (BHL) of tritium by analysing routine bioassay samples of radiation workers. During 2007-2009 year, 72,100 urine bioassay samples of the workers were analysed by liquid scintillation counting technique for internal dose monitoring for tritium. Two hundred and two subjects were taken for study with minimum 3 µCiL(-1) tritium uptake in their body fluid. The BHL of tritium of subjects ranges from 1 to 16 d with an average of 8.19 d. Human data indicate that the biological retention time ranges from 4 to 18 d with an average of 10 d. The seasonal variations of the BHL of tritium are 3.09 ± 1.48, 6.87 ± 0.58 and 5.73 ± 0.76 d (mean ± SD) for summer, winter and rainy seasons, respectively, for free water tritium in the coastal region of Karnataka, India, which shows that the BHL in summer is twice that of the winter season. Also three subjects showed the BHL of 101.73-121.09 d, which reveals that organically bound tritium is present with low tritium uptake also. The BHL of tritium for all age group of workers is observed independent of age and is shorter during April to May. The distribution of cumulative probability vs. BHL of tritium shows lognormal distribution with a geometric mean of 9.11 d and geometric standard deviation of 1.77 d. The study of the subjects is fit for two-compartment model and also an average BHL of tritium is found similar to earlier studies.

Hepatoprotective properties of Caesalpinia sappan Linn. heartwood on carbon tetrachloride induced toxicity.

Aim of the study was to investigate the methanol and aqueous extracts of heartwood of C. sappan for its hepatoprotective activity against CCl4 induced toxicity in freshly isolated rat hepatocytes and animals. Freshly isolated rat hepatocytes were exposed to CCl4 (1%) along with/without various concentrations of methanolic and aqueous extract of C. sappan (1000-800 microg/ml) and the levels of selected liver enzymes were estimated. Antihepatotoxic effect of methanolic extract was observed in freshly isolated rat hepatocytes at concentrations 1000-800 microg/ml and was found to be similar to that of standard drug silymarin. Wistar strain albino rat model was used for the investigation of in vivo hepatoprotective properties of aqueous and methanolic extract of C. sappan (100 and 200 mg/kg body weight). Liver damage was induced by ip administration of CCl4 (30%) suspended in olive oil (1 ml/kg body weight). Both the tested extracts showed potent hepatoprotective activity at 200 mg/kg body weight test dose which was comparable with that of the standard silymarin used in similar test dose. The methanolic and aqueous extract was able to restore the biochemical levels to normal which were altered due to CCl4 intoxication in freshly isolated rat hepatocytes and also in animals.

Antioxidant activity of Hypericum hookerianum Wight and Arn.

Methanolic extracts of leaf, root, flower and aerial parts of Hypericum hookerianum were assessed for in vitro antioxidant activity using eight different models. Total antioxidant capacity, phenol and flavanol content of the extracts were determined to correlate between their antioxidant activity and constituents present therein. Results of in vitro antioxidant study suggest that extracts from leaf and flower have strong antioxidant potential. Leaf extract (100 & 200 mg kg(-1) b.w. p.o.) that showed maximum activity was selected for in vivo antioxidant studies using a CCl(4)-intoxicated rat model. The effects of extracts on lipid peroxidation (LPO), superoxide dismutase (SOD) and catalase (CAT) in serum and liver homogenate were analysed. CCl(4) treatment caused a significant increase in the level of CAT and SOD and a significant decrease in the level of LPO in a dose-dependent manner when compared to CCl(4) treated control. The results indicate the strong antioxidant nature of H. hookerianum leaf extract.

Gangrene of the penis in a diabetic male with multiple amputations and follow up.

A 60-year-old insulin dependent, diabetic male with severe atherosclerosis requiring multiple amputations in the extremities in the past, with normal renal function presented with gangrene of glans penis. He was initially treated with debridement but as the gangrene progressed, partial penile amputation was performed. He showed no further progress of the disease and had no voiding difficulties even after 4 years of follow up.

An assessment of plankton population of Cauvery river with reference to pollution.

Studies on plankton of river Cauvery water, Mettur, Salem District, Tamil Nadu was made to assess the pollution of water from January 2003 to December 2003. The qualitative and quantitative evaluation of the variation in river water showed high quantity of phytoplankton and zooplankton population throughout the study period and rotifers formed dominated group over other groups of organisms. The present study revealed that the water of river Cauvery is highly polluted by direct contamination of sewage and other industrial effluents.

Antiviral activity of medicinal plants of Nilgiris.

BACKGROUND & OBJECTIVES: Medicinal plants have been traditionally used for different kinds of ailments including infectious diseases. There is an increasing need for substances with antiviral activity since the treatment of viral infections with the available antiviral drugs often leads to the problem of viral resistance. Herpes simplex virus (HSV) causes a variety of life threatening diseases. Since the chemotherapeutic agents available for HSV infections are either low in quality or limited in efficiency, there is a need to search for new and more effective antiviral agents for HSV infections. Therefore in the present study 18 plants with ethnomedical background from different families were screened for antiviral activity against HSV-1. METHODS: Different parts of the plants collected from in and around Ootacamund, Tamil Nadu were extracted with different solvents to obtain crude extracts. These extracts were screened for their cytotoxicity against Vero cell line by assay microculture tetrazolium (MTT) trypan blue dye exclusion, proteins estimation and 3H labeling. Antiviral properties of the plant extracts were determined by cytopathic effect inhibition assay and virus yield reduction assay. RESULTS: Three plant extracts Hypericum mysorense, Hypericum hookerianum and Usnea complanta exhibited significant antiviral activity at a concentration non toxic to the cell line used. The extracts of Melia dubia, Cryptostegia grandiflora and essential oil of Rosmarinus officinalis showed partial activity at higher concentrations. INTERPRETATION & CONCLUSION: Some of the medicinal plants have shown antiviral activity. Further research is needed to elucidate the active constituents of these plants which may be useful in the development of new and effective antiviral agents.

Antitumor activity of total alkaloid fraction of solanum pseudocapsicum leaves.

The total alkaloid fraction of the methanolic extract of Solanum pseudocapsicum leaves was tested for its in-vivo antitumor activity against Dalton's Lymphoma Ascites model in mice. The total alkaloid fraction at 2.5 and 5.0 mg/kg body weight doses exhibited antitumor activity as revealed by the significant increase in the mean survival time and the percentage increase in life span of tumor bearing mice. The antitumor activity observed may be due to its cytotoxic properties. However the treatment caused a significant decrease in the body weight below the normal indicating the toxicity of the treatment.

In vitro cytotoxicity and antitumour properties of Hypericum mysorense and Hypericum patulum.

The methanol extracts of the aerial parts of Hypericum mysorense and Hypericum patulum were tested for in vitro cytotoxicity on HEp-2, RD and Vero cell lines and antitumour activity using DLA and HEp-2 cell lines. The cell viability and morphological changes were assessed. Of these extracts, Hypericum patulum (stem) extract showed strong cytotoxicity against all the cell lines used. The CTC50 of the Hypericum patulum (stem) extract was 1.71 microg/mL for HEp-2, 1.53 microg/mL for RD and 2.23 microg/mL for Vero cell lines. The Hypericum patulum (leaves) and Hypericum mysorense (aerial parts) extracts showed moderate cytotoxicity and Hypericum patulum (aerial parts) extract did not show any cytotoxicity up to 1,000 microg/mL concentration. In the clonogenic assay, no colony formation was observed at a concentration of 300 micro g/mL and above for Hypericum mysorense (aerial parts), 400 microg/mL and above for Hypericum patulum (leaves) and 500 microg/mL and above for Hypericum patulum (stem) extracts. In the short term antitumour studies using DLA cells, 50% viability was observed in the concentration range 100-200 microg/mL for Hypericum patulum (leaves and stem) and 200-400 microg/mL for Hypericum mysorense (aerial) extract. In the long term antitumour activity using the HEp-2 cell line, no colony formation was observed over a concentration of 1.6 microg/mL for the Hypericum patulum (stem) extract.