Secure malicious node detection in flying ad-hoc networks using enhanced AODV algorithm

In wireless networking, the security of flying ad hoc networks (FANETs) is a major issue, and the use of drones is growing every day. A distributed network is created by a drone network in which nodes can enter and exit the network at any time. Because malicious nodes generate bogus identifiers, FANET is unstable. In this research study, we proposed a threat detection method for detecting malicious nodes in the network. The proposed method is found to be most effective compared to other methods. Malicious nodes fill the network with false information, thereby reducing network performance. The secure ad hoc on-demand distance vector (AODV) that has been suggested algorithm is used for detecting and isolating a malicious node in FANET. In addition, because temporary flying nodes are vulnerable to attacks, trust models based on direct or indirect reliability similar to trusted neighbors have been incorporated to overcome the vulnerability of malicious/selfish harassment. A node belonging to the malicious node class is disconnected from the network and is not used to forward or forward another message. The FANET security performance is measured by throughput, packet loss and routing overhead with the conventional algorithms of AODV (TAODV) and reliable AODV secure AODV power consumption decreased by 16.5%, efficiency increased by 7.4%, and packet delivery rate decreased by 9.1% when compared to the second ranking method. Reduced packet losses and routing expenses by 9.4%. In general, the results demonstrate that, in terms of energy consumption, throughput, delivered packet rate, the number of lost packets, and routing overhead, the proposed secure AODV algorithm performs better than the most recent, cutting-edge algorithms.

In Vitro Evaluation of Extracts From Ixora Species for a Potential Phytosomal Formulation

Background Ixora species are perennial shrubs and flowering plants belonging to the family Rubiaceae. The leaf and flower parts of Ixora coccinea (I. coccinea) andIxora alba (I. alba) were aimed at isolating their active fractions. The present study was to determine in vitro antitumor activity against malignant melanoma cell lines for phytosome formulation. Materials and methods Two species, I. coccinea (red flowers and leaves) and I. alba (white flowers and leaves), were selected, and this study focused on determining the active fraction by comparing the in vitro antimicrobial and antioxidant potentials of petroleum ether, chloroform, ethyl acetate, and hydroalcoholic (ethanol:water, 70:30 v/v) extracts. The identified potent extract was subjected to in vitro anticancer activity in malignant melanoma cell lines. Results A phytochemical study revealed phytosterols, flavonoids, proteins, amino acids, alkaloids, carbohydrates, phenols, tannins, and diterpenes. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay was used to evaluate the antioxidant effect of I. coccinea and I. alba leaf and flower extracts. In the DPPH assay, I. coccinea flower hydroalcoholic extract (ICFHA) had an IC50 value of 248.99 µg/mL, and I. coccinea leaf hydroalcoholic extract (ICLHA) had an IC50 value of 268.87 µg/mL. These two extracts had a lower value with a higher antioxidant effect. In the total antioxidant assay, I. coccinea leaf ethyl acetate extract (ICLEA) and I. coccinea leaf chloroform extract (ICLCE) have 77.4 ± 0.05 and 68.9 ± 0.03 mg of ascorbic acid equivalent per gm of extract, respectively. These two extracts exhibited a high antioxidant effect. The antimicrobial potential was evaluated using selected bacterial and fungal strains using the agar-well diffusion method. Petroleum ether and chloroform extracts of I. coccinea and I. alba leaves and flowers did not possess antimicrobial activity with any of the bacterial or fungal strains. An ethyl acetate extract and a hydroalcoholic extract of I. coccinea leaves and flowers showed antimicrobial activity against Enterococcus faecalis, Candida albicans, and Staphylococcus aureus. An ethyl acetate extract of I. coccinea flower and a hydroalcoholic extract of I. alba leaf showed a significant zone of inhibition when compared with standard chloramphenicol for all three selected strains, which may be due to the presence of active phytoconstituents. ICLHA showed a MIC of ≤300 µg/mL for Enterococcus faecalis and Staphylococcus aureus and ≤400 µg/mL for Candida albicans microbial strains. The high total flavonoid content was reported in ICLEA at 771.31 µg/mL and in I. coccinea flower ethyl acetate extract (ICFEA) at 694.69 µg/mL. High-performance thin layer chromatography (HPTLC) analysis showed a high quercetin (QCE) content in the ICLEA extract. To prove the in vitro skin anticancer activity, an MTT assay was performed for the ICLEA extract in a malignant melanoma cell line, and the IC50 value was reported as 7.96 µg/mL. Conclusion I. coccinea leaf ethyl acetate extract revealed a significant total flavonoid content in analysis through the aluminum chloride method, and the presence of a high QCE content was confirmed by HPTLC analysis. The in vitro skin anticancer activity of ICLEA was confirmed by the MTT assay; therefore, it was concluded that the ICLEA extract was a potent fraction and was selected to develop a phytosome.

Green HPLC Method for Simultaneous Analysis of Three Natural Antioxidants by Analytical Quality by Design

BACKGROUND

Glutathione, silybin, and curcumin are well-known potential antioxidants that are recommended as adjuvant therapy in cancer treatment.

OBJECTIVE

Based on the principles of Analytical Quality by Design (AQbD) and green analytical chemistry, a simple, robust, and environmentally benign HPLC method for the simultaneous estimation of glutathione, silybin, and curcumin in bulk and formulation was performed.

METHOD

Elution was achieved by an Agilent Eclipse XDB C18 (150 mm × 4.6 mm id, 3.5 μm) column using a gradient mobile phase composed of ethanol-water pH 6.7 (with 0.1%, v/v orthophosphoric acid) and 1.07 mL/min flow rate with PDA detection at 215 nm. Critical method variables were identified by risk assessment using an Ishikawa diagram, and multivariate optimization of the experimental conditions for the HPLC technique was accomplished by central composite design using design of experiments (DoE) software.

RESULTS

The separation was achieved within 15 min, where the retention time of glutathione, silybin, and curcumin were 3.3, 4.9, and 7.3 min, respectively. The standard curve was linear in the range of 3.75-26.25 µg/mL for glutathione, 62.50-437.50 µg/mL for silybin, and 12.5-87.50 µg/mL for curcumin. The developed method was validated as per ICH guidelines Q2 (R1), and all the parameters are within specified limits.

CONCLUSIONS

The proposed method is simple, precise, and robust, which can be employed for routine analysis and also concluded to be a greener approach according to AGREE, Green Analytical Procedure Index, and analytical eco-scale tools.

HIGHLIGHTS

The chosen antioxidants were evaluated for the very first time simultaneously using the chromatographic technique in bulk and dosage forms employing green solvents. The peak purity of all three compounds was studied using a PDA detector. Wastage was reduced in terms of time, cost, and solvents by employing AQbD elements and tools. Complete application of environmentally sustainable safe solvents were employed.

Coherent Doppler LIDAR with long-duration frequency-modulated pulses for wind sensing

A coherent Doppler LIDAR (CDL) with long-duration frequency-modulated pulses was demonstrated and validated by analyzing the data observed by a prototype. In traditional CDL using short-duration single-frequency pulses (PCDL; pulsed CDL), there exists a trade-off relationship between distance and velocity resolution. Meanwhile, in earlier work, a theoretical framework of CDL using long-duration frequency-modulated pulses (FMCDL; frequency-modulated CDL) was put forth to eliminate the trade-off. We developed the prototype to be operated as both a PCDL and FMCDL. Analyses of data observed by the PCDL and FMCDL modes showed that the FMCDL worked in good agreement with the PCDL for wind ranging and velocimetry. Furthermore, the performance of the FMCDL in terms of received power and resolution of distance and velocity was quantitatively consistent with ones theoretically expected.

Incidence of metabolic syndrome and its characteristics of patients attending a diabetic outpatient clinic in a tertiary care hospital

OBJECTIVE

We sought to evaluate the incidence of metabolic syndrome and non-metabolic syndrome among type 2 diabetic patients attending the diabetic outpatient clinic at tertiary care hospital, Warangal.

MATERIALS AND METHODS

A cross-sectional study was conducted in a period of 6 months from January 2011 to June 2011. The study group consisted of 75 type 2 diabetic patients. They were screened for hypertension, hyperlipidemia, obesity, and clinical characteristics, and other co-morbidities were recorded. Metabolic syndrome diagnosis was made as per ATP III guidelines.

RESULTS

The prevalence of metabolic syndrome was significant in men (54.8%) compared to women (45.2%). Incidence of metabolic syndrome was found to be more in normal weight patients (43.56%). Low high density lipoprotein (HDL) levels were observed in both rural (90.63%) and urban (95.65%) patients with metabolic syndrome, followed by increase in waist circumference. The mean HDL level was found to be 23.77 mg/dl. Patients in the age group 51-60 years were found to be more affected with metabolic syndrome. Sedentary household female patients (58.3%) and illiterates (41.8%) were suffering from metabolic syndrome. Patients with metabolic syndrome had been suffering with diabetes (duration of diabetes) from 1 to 5 years. In summary, this cross-sectional study characterizes the metabolic and non-metabolic syndromes of type 2 diabetes patients living in Telangana regions, using ATP III guidelines, and generates a biological resource that enables further investigation of numerous hypotheses related to genetic exposure of both in a population.

CONCLUSION

These results suggest that higher prevalence of metabolic syndrome was observed in non-obese male patients and was significantly associated with aging. Nevertheless, further studies are required to confirm the metabolic syndrome in larger population.

Surveillance of drug-resistant tuberculosis in the state of Gujarat, India

BACKGROUND

Limited information about the prevalence of drug-resistant tuberculosis (TB) has been reported from India, the country with the world's highest burden of TB. We conducted a representative state-wide survey in the state of Gujarat (2005 population: 56 million).

METHODS

Mycobacterium tuberculosis isolates from a representative sample of new and previously treated smear-positive pulmonary TB (PTB) cases were subjected to drug susceptibility testing (DST) against first-line drugs at a World Health Organization supranational reference laboratory. Isolates found to have at least both isoniazid (INH) and rifampicin (RMP) resistance (i.e., multidrug-resistant TB [MDR-TB]) were subjected to second-line DST.

RESULTS

Of 1571 isolates from new patients, 1236 (78.7%) were susceptible to all first-line drugs, 173 (11%) had any INH resistance and MDR-TB was found in 37 (2.4%, 95%CI 1.6-3.1). Of 1047 isolates from previously treated patients, 564 (54%) were susceptible to all first-line drugs, 387 (37%) had any INH resistance and MDR-TB was found in 182 (17.4%, 95%CI 15.0-19.7%). Among 216 MDR-TB isolates, 52 (24%) were ofloxacin (OFX) resistant; seven cases of extensively drug-resistant TB (XDR-TB) were found, all of whom were previously treated cases.

CONCLUSION

MDR-TB prevalence remains low among new TB patients in Gujarat, but is more common among previously treated patients. Among MDR-TB isolates, the alarmingly high prevalence of OFX resistance may threaten the success of the expanding efforts to treat and control MDR-TB.

Effect of esophagus status and catheter configuration on multiple intraluminal impedance measurements

Multiple intraluminal impedance measurement is used to investigate the esophagus condition. This procedure provides information about the esophagus status, reflux occurrence and clearance mechanism. This paper presents finite-element approximation of the forward problem of the catheter inside the esophagus, relating the real data obtained from multiple intraluminal impedance to the solution obtained from the finite-element approximation. Investigation of the effect of the esophagus status on the impedance, and the correlation between various factors that affect the impedance are presented. The results of this paper provide theoretical bases for relating the esophagus condition to the impedance waveforms.

Numerical investigations of intraluminal impedance

The measurement of the electrical impedance inside the esophagus provides information about its status, and is used in the study of the gastroesophageal reflux. This paper presents numerical modeling of the forward problem of the catheter inside the esophagus. The results of the numerical solution for a simple geometry is compared against solution formulated from Green's function approach. This paper also presents investigation of the effect of the esophagus status on the impedance, and the correlation between various factors that affect the impedance. The results of this paper provides a way of relating the esophagus condition to the impedance waveforms as well as in the interpretation of the resulting impedance signals.

Computation of intraluminal impedance

The measurement of the electrical impedance inside the esophagus provides information about its status, and is being explored in the study of the gastroesophageal reflux. This paper presents theoretical computation of impedance inside the esophagus. The results of the numerical solution for a simple geometry are compared against the solution formulated from the Green's function approach. The effect of the electrode configuration on the resulting impedance is studied as an application of the methodology developed in this paper. The results of this paper will be useful in the design of an intraluminal impedance catheter as well as in the interpretation of the resulting impedance signals.

Analysis of intraluminal impedance measurements

Intraluminal impedance is an emerging technique to monitor the esophagus so that the occurrence of gastroesophageal reflux episodes can be observed. The impedance traces of the esophagus have wide variations which correspond to the occurrence of activities such as swallow or reflux that cause the impedance to change. This paper presents a technique to detect and classify reflux episodes from intraluminal impedance. Evaluation of the technique based on 660 h of combined data from 30 patients showed that the proposed methodology can detect episodes in the esophagus to a sensitivity of 89% with positive predictivity of 83%.

Simulation of intraluminal impedance

Intraluminal impedance describes the electrical impedance inside the Gastrointestinal tract (GIT). These observations provide information about the state of the GIT that assists in the diagnosis. This paper presents numerical modeling of impedance measurements inside the GIT in order to evaluate the data generated under different conditions, such as various catheter configurations, different esophagus wall widths, different positions of the catheter inside the GIT and the presence of materials with different conductivities between the electrodes. The model used in the simulation assumes realistic esophagus and the values of the conductivities are obtained from literature. The results of this paper will be useful in the design and interpretation of the GIT impedance measurements.

Host range and variability of calcium binding by surface loops in the capsids of canine and feline parvoviruses

Canine parvovirus (CPV) emerged in 1978 as a host range variant of feline panleukopenia virus (FPV). This change of host was mediated by the mutation of five residues on the surface of the capsid. CPV and FPV enter cells by endocytosis and can be taken up by many non-permissive cell lines, showing that their host range and tissue specificity are largely determined by events occurring after cell entry. We have determined the structures of a variety of strains of CPV and FPV at various pH values and in the presence or absence of Ca(2+). The largest structural difference was found to occur in a flexible surface loop, consisting of residues 359 to 375 of the capsid protein. This loop binds a divalent calcium ion in FPV and is adjacent to a double Ca(2+)-binding site, both in CPV and FPV. Residues within the loop and those associated with the double Ca(2+)-binding site were found to be essential for virus infectivity. The residues involved in the double Ca(2+)-binding site are conserved only in FPV and CPV. Our results show that the loop conformation and the associated Ca(2+)-binding are influenced by the Ca(2+) concentration, as well as pH. These changes are correlated with the ability of the virus to hemagglutinate erythrocytes. The co-localization of hemagglutinating activity and host range determinants on the virus surface implies that these properties may be functionally linked. We speculate that the flexible loop and surrounding regions are involved in binding an as yet unidentified host molecule and that this interaction influences host range.

The structure of tobacco ringspot virus: a link in the evolution of icosahedral capsids in the picornavirus superfamily

BACKGROUND

Tobacco ringspot virus (TRSV) is a member of the nepovirus genus of icosahedral RNA plant viruses that cause disease in fruit crops. Nepoviruses, comoviruses and picornaviruses are classified in the picornavirus superfamily. Crystal structures of comoviruses and picornaviruses and the molecular mass of the TRSV subunit (sufficient to accommodate three beta-barrel domains) suggested that nepoviruses may represent a link in the evolution of the picornavirus capsids from a T = 3 icosahedral virus. This evolutionary process is thought to involve triplication of the capsid protein gene, to encode a three-domain polyprotein, followed by development of cleavage sites in the interdomain linking regions. Structural studies on TRSV were initiated to determine if the TRSV subunit corresponds to the proposed uncleaved three-domain polyprotein.

RESULTS

The 3.5 A resolution structure of TRSV shows that the capsid protein consists of three beta-barrel domains covalently linked by extended polypeptides. The order of connectivity of the domains in TRSV confirms the proposed connectivity for the precleaved comovirus and picornavirus capsid polyprotein. Structural differences between equivalent domains in TRSV and comoviruses are confined to the external surface loops, interdomain connecting polypeptides and N termini. The three different domains within TRSV and comoviruses are more closely related at the structural level than the three individual domains within picornaviruses.

CONCLUSIONS

The structural results confirm the notion of divergent evolution of the capsid polyproteins of nepoviruses, comoviruses and picornaviruses from a common ancestor. A number of residues were found to be conserved among various nepoviruses, some of which stabilize the quaternary structure of the three domains in the TRSV capsid protein subunit. Two conserved regions were identified on the external surface of TRSV, however, mutational studies will be needed to understand their functional significance. Nepoviruses transmitted by the same nematode species do not share regions with similar amino acid composition on the viral surface.

Crystallization and preliminary X-ray analysis of tobacco ringspot virus

Tobacco ringspot virus, a plant virus that is believed to fill an apparent niche in the evolution of picornavirus-like capsids, has been crystallized by vapor diffusion with potassium phosphate and polyethylene glycol buffered at pH 6.5 in a new crystal form. The monoclinic crystals belong to the space group C2 with unit-cell dimensions of a = 407.1, b = 399.7, c = 285.9 A and beta = 129.1 degrees and diffract synchrotron radiation to 3.3 A. One half of a virus particle constitutes the crystallographic asymmetric unit. The orientation of the virus particle in the unit cell was determined by the rotation function analysis of a partial data set that has been collected at CHESS using image plates. Development of a suitable phasing model for the high-resolution structure determination of TRSV with the real-space molecular replacement technique is now under way.

Radar and Surface Measurement of Rainfall during CaPE: 26 July 1991 Case Study

Conventional usage of multiparameter radar measurements for rainfall estimation has been associated with tracking the variability of the raindrop size distribution. The use of multiparameter radar measurements in a statistical framework to estimate rainfall is presented in this paper. The techniques developed in this paper are applied to the radar and rain gauge measurement of rainfall observed on 26 July 1991, during the Convection and Precipitation Electrification program. Conventional pointwise estimates of rainfall are also compared. The probability matching procedure, when applied to the radar and surface measurements shows that multiparameter radar algorithms can match the probability distribution functions better than the reflectivity based algorithms, thereby indicating the potential of multiparameter radar measurements for statistical approach to rainfall estimation.

Do silver stained structures in vaginal parabasal cells identify a different population of cells in buffaloes?

A modified single step silver colloidal staining method for interpretation of routine vaginal smears of buffaloes which aids in analysing every component under light microscope with minimum efforts has been suggested, and it can be adopted in all clinical laboratories. A novel population of parabasal cells has been described which was distinct in morphology and nuclear distribution of silver stained structures (SSS). These SSS has been designated as the 'parabasal dots'. The significance of these cells needs further investigation and confirmation.

Hypokalemic paralysis

A case of Hypokalemic paralysis is reported which had an atypical onset and clinical features. The paralysis totally recovered on replacement of potassium.