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Software Defined Networking (SDN) expands the networking capabilities using abstraction, open-source protocols, energy efficiency, and programmable features for controlling the forwarding devices at the network edges and intensifying the network performance. Despite all the unprecedented features, SDN still might get exploited by an attacker to launch Distributed Denial of Service (DDoS) attacks at SDN planes i.e. Application, Control, and Data planes. Substantially, the DDoS attacks have been implemented by sending volumetric malicious traffic to exhaust the targeted resources. Such attacks can be easily observed and detected due to their high packet rates. Thus, now attackers are fascinated by the Low-Rate DDoS (LR-DDoS) attacks. In recent years, many efforts have been devoted to defending against the DDoS attacks in SDN. As the attackers benefit from the programmable nature of SDN, an in-detail review of various DDoS attacks and their corresponding defense approaches are essential. Initially, this paper presents a conceptual architecture of SDN and discusses the vulnerable locations in each plane that are exploited by the attacker for launching the DDoS attacks. Secondly, the work offers a detailed classification of DDoS attacks (HR-DDoS and LR-DDoS) concerning the SDN planes and the corresponding defense solutions. The convergence point of this research work is to discover the related security issues and stimulate the network researchers to counter these issues by employing the respective SDN DDoS defense solutions efficiently. Finally, the work gets concluded with a focus on the respective future challenges. [ABSTRACT FROM AUTHOR]

This manuscript proposes a novel technique of synchronization to synchronize four non-identical chaotic systems together. The newly introduced scheme is named as anti-difference quadratic compound synchronization. We have also used the multi-switching of signals to increase the complexity of the proposed scheme. Lorenz, Rössler, and the modified financial systems are taken as drive systems, and the modified Shimizu–Morioko system is taken as the response system to illustrate the obtained results. Lyapunov stability is used to design suitable controllers. Numerical simulations and graphs are presented using MATLAB to verify the theoretical results. [ABSTRACT FROM AUTHOR]

There have been a number of new technologies and applications that can track various events and activities in a variety of environments. Software Defined Networking (SDN) is one of these technologies that has the ability to bring the unanticipated changes in the networking space. SDN aids in the implementation and management of new networks, lowering associated expenses. SDN's unique characteristics make it ideal for monitoring the harsh environmental conditions. Agriculture, Military, Industry, Natural disasters, Health monitoring, Crisis response, and Emergency management are just few examples of common applications. In the last few decades, some of these applications have been of critical relevance and the subject of ongoing research. SDN becomes increasingly popular owing to its perfect benefits, which include aid in various surveillance scenarios. Thus, this survey covers several areas of surveillance and assists the readers to have a better grasp of SDN-based surveillance. Furthermore, various open research problems and the related surveillance challenges have also been explored. [ABSTRACT FROM AUTHOR]

This research article mainly focuses on the development of a new six-dimensional dynamical system, principally based on the Lü system. The dynamic characteristics of this introduced system are evaluated and investigated by providing its 2D and 3D plots, time series for each state, discussing bifurcation scenarios and dissipation, the Poincaré map, and calculating its Kaplan–Yorke dimension. This system achieves hyper-chaos with two positive Lyapunov exponents. The generic stagnation points are computed, and their stability analysis is covered. The proposed system has also been studied via circuit implementation on Multisim. Towards the end of the manuscript, hybrid projective combination–combination synchronization among multiple drives and responses is attained through efficient adaptive control. Based on the principles of Lyapunov stability, several nonlinear controllers are created. All the acquired analytical results in the text are validated for their efficacy and viability through simulations on MATLAB. [ABSTRACT FROM AUTHOR]

Calculus in the urethra of the female is very unusual. The patient remains asymptomatic or uncommonly presents with symptoms of dysuria, post-void urinary dribbling, and dyspareunia. If asymptomatic, it can be diagnosed incidentally on gynecological examination. Being hard in consistency, it may mimic metastatic lesion. We present a case of a female who presented to us for management of ovarian mass. On routine examination there was a hard mass in her vagina which was suspected to be a metastatic lesion. This mass on evaluation came out to be a urethral diverticulum with a large calculus. Very large urethral calculus are a very rare presentation in a female. [ABSTRACT FROM AUTHOR]

In this paper, we have introduced a novel five-dimensional (5D) hyperchaotic system by extending the well-known Lorenz system. The dynamical properties of the system are analysed by calculating the Lyapunov exponents, graphing the phase portraits, bifurcation diagrams, the time series and by finding the Kaplan–Yorke dimension. The equilibrium points of the system have been calculated and the stability analysis of these equilibrium points is discussed. Hybrid function projective synchronisation has been carried out between the identical systems using the scheme of adaptive control. Suitable controllers have been designed to attain the desired synchronisation between the systems using Lyapunov stability theory. The theoretical results have been validated by performing numerical simulations using the MATLAB. [ABSTRACT FROM AUTHOR]

Smart transportation systems have been the focus of research due to the development of smart cities. However, existing vehicular networks are not sufficient enough to fulfill the vision of futuristic smart cities due to limited flexibility, scalability, poor connection, and insufficient intelligence. These technological hurdles make the role of Software-Defined Networking (SDN) very important to improve the overall performance of the existing vehicular networks considering the unique properties of SDN such as Decoupling of network planes and Real-time network programming. This leads to the development of Software-Defined Vehicular Networks (SDVNs). SDVNs help to realize the development of smart transportation systems which further helps to optimize the vision of truly smart cities. However, the security remains a consistent concern due to the increased mobility, larger attack surface, and improvised future attack vector. This work includes the different design components, and offers a detailed survey to understand different security issues including the architectural and functional ones. Additionally, multiple security solutions are discussed including Service-based, Infrastructure-based, and Application-based solutions. Furthermore, the work also covers the possible challenges in the development of SDVNs based on Improved Architectural Development, Holistic Integration, Effective Orchestration, Environmental Volatility Handling, Global Network Management, Efficient Components/Technologies Integration, Diverse Security Offerings, and Design Issues' Maintenance. Lastly, the work highlights the resultant opportunities based on Application, Open Research, Network Management, Device Configuration, Traffic Management, QoS, and Efficient Routing. [ABSTRACT FROM AUTHOR]

Key message: Heavy doses of gamma irradiation can reduce linkage drag by disrupting large sized alien translocations and promoting exchanges between crop and wild genomes. Resistance to mustard aphid (Lipaphis erysimi) infestation was significantly improved in Brassica juncea through B. juncea-B. fruticulosa introgression. However, linkage drag caused by introgressed chromatin fragments has so far prevented the deployment of this resistance source in commercial cultivars. We investigated the patterns of donor chromatin segment substitutions in the introgression lines (ILs) through genomic in situ hybridization (GISH) coupled with B. juncea chromosome-specific oligonucleotide probes. These allowed identification of large chromosome translocations from B. fruticulosa in the terminal regions of chromosomes A05, B02, B03 and B04 in three founder ILs (AD-64, 101 and 104). Only AD-101 carried an additional translocation at the sub-terminal to intercalary position in both homologues of chromosome A01. We validated these translocations with a reciprocal blast hit analysis using shotgun sequencing of three ILs and species-specific contigs/scaffolds (kb sized) from a de novo assembly of B. fruticulosa. Alien segment substitution on chromosome A05 could not be validated. Current studies also endeavoured to break linkage drag by exposing seeds to a heavy dose (200kR) of gamma radiation. Reduction in the size of introgressed chromatin fragments was observed in many M3 plants. There was a complete loss of the alien chromosome fragment in one instance. A few M3 plants with novel patterns of chromosome segment substitutions displayed improved agronomic performance coupled with resistance to mustard aphid. SNPs in such genomic spaces should aid the development of markers to track introgressed DNA and allow application in plant breeding. [ABSTRACT FROM AUTHOR]

Silver nanomaterials (AgNMs) ubiquitously known for their biological applications are studied here in terms of their shape-dependent antibacterial and anti-biofilm effect. Chemically synthesized nano-cubes (AgNCs) with size range around 150–200 nm were compared for their biological activity with commercial nano-sphere (AgNS) of comparable size (~160 nm). The antibacterial activity against both Escherichia coli and Staphylococcus aureus showed higher activity for nano-cubes compared with nano-spheres.The synergistic role of AgNMs with antibiotic ampicillin was also found promising. A four times enhancement and an increase of nearly 25% of antibiotic activity at 0.0625 mg ml–1 concentration was found with 0.05 mg ml–1 of AgNCs in agar and broth media, respectively. Anti-biofilm effect towards E. coli and S. aureus was also evaluated. AgNCs showed equal importance in biofilm disruption with 20% inhibition activity, which was yet again found better in-comparison with AgNSs. The study shows that AgNCs with distinct faces and edges could show efficient anti-bacterial effect and so such intelligently designed material could pave path for imminent medical challenges. [ABSTRACT FROM AUTHOR]

Background: Unlike adults, primary membranous nephropathy (PMN) comprises only 1–2% of childhood nephrotic syndrome. The clinical behaviour of PMN in children is not explicit and we report upon clinical presentation and outcome. Methods: This prospective study includes children and adolescents (< 20 years) with biopsy-proven PMN without secondary causes. Anti-PLA2R assessment: before and after completing therapy. Outcome: percentage of patients achieving remission. Results: Study cohort included 48 (M:F ratio 1.1:1) patients and median age 17 (IQR 15–18) years, with 35 (72.9%) PLA2R related. Median interval from symptom onset to presentation was 5 months, where median proteinuria, serum albumin and creatinine were 4.9 g/day, 2.1 g/dL and 0.63 mg/dL, respectively. Forty-seven patients received immunosuppressive therapy, with various agents used as first-line therapy: cyclical CYC/GC (53.1%), CNI/GC (21.3%), rituximab (14.9%), prednisolone alone (4.3%), azathioprine (4.3%) and mycophenolate mofetil (2.1%). Median follow-up was 29 (14, 59) months. At 6 months, 11 (24.4%) and 17 (37.7%) had complete remission (CR) or partial remission (PR), while at last follow-up (median 29 months), 20 (45.4%) and 14 (31.8%) had CR and PR respectively. No significant differences in outcome were observed with different agents. A total of 60% patients treated with rituximab as first line/for relapsing disease, and all cases with resistant disease receiving rituximab had CR or PR at last follow-up. PLA2R antibody presence was associated with clinical outcome. Conclusions: Three-quarters of PMN in children and adolescents is PLA2R related and two-thirds respond to immunosuppressive therapy. Rituximab is a promising agent to manage PMN in children. Anti-PLA2R is associated with clinical outcomes. [ABSTRACT FROM AUTHOR]

The integration of cloud computing with Software Defined Networking (SDN) addresses several challenges of a typical cloud infrastructure such as complex inter-networking, data collection, fast response, etc. Though SDN-based cloud opens new opportunities, the SDN controller may itself become vulnerable to several attacks. The unique features of SDN are used by the attackers to implement the severe Distributed Denial of Service (DDoS) attacks. Several approaches are available in literature to defend against the traditional DDoS flooding attacks in SDN-cloud. To elude the detection systems, attackers try to employ the cultivated attack strategies. Such sophisticated DDoS attack strategies are implemented by generating low-rate attack traffic. The most common type of Low-Rate DDoS (LR-DDoS) attack is the Shrew attack. The existing approaches are not capable to detect, mitigate, and traceback such attacks. Thus, this work discusses a new mechanism which not only detects and mitigates the shrew attack but traces back the location of the attack sources as well. The attack is detected using the information entropy variations, and the attack sources are traced-back using the deterministic packet marking scheme. The experiments are performed in a real SDN-cloud scenario, and the experimental results show that the approach requires 1 packet and 8.27 packets on an average to locate the bots and attackers respectively. The approach detects and traces back the attack sources in between 14.45 ms to 10.02 s and provides 97.6% accuracy. [ABSTRACT FROM AUTHOR]

Distributed Denial-of-Service (DDoS) attack has been a serious threat to the availability feature of cloud computing. As traditional DDoS attacks are implemented using a huge volume of malicious traffic, the detection of such attacks becomes a naive task. To evade this detection, attackers are moving towards the Low-Rate DDoS (LRDDoS) attacks. The stealthy behavior of LRDDoS attack makes it difficult to get detected due to its low volume traffic. The existing frequency-domain approaches for LRDDoS detection are not feasible in terms of computational and storage requirements. This paper aims to propose a lightweight, accurate, and adaptive approach for the detection of LRDDoS attacks in frequency-domain. In this paper, the LRDDoS attack is detected by analyzing the power spectral distribution. The novelty of the proposed approach is to calculate the power spectral density using Fast Hartley Transform (FHT). The FHT processes real-valued input data, and has low computational and storage complexities. The approach is implemented on OpenStack cloud platform, and the aggregate network traffic (external and internal) is captured and analyzed. Experimental results show that the computational and storage complexities involved in FHT are lower than other transformation algorithms' complexities. Thus, the approach provides faster response with an average detection time of 60.16 s. The average true negative and true positive rates obtained by the proposed approach are 99.83% and 99.46% respectively, which are competitive. [ABSTRACT FROM AUTHOR]

Vitamin B12 (cobalamin) is a cobalt-containing compound that acts as an essential co-factor for various enzymes involved in the metabolic processes of the living cells. The constructed FRET Sensor for Vitamin Anemia Linked (SenVitAL) displayed marginal FRET efficiency. Here, we report the development of a molecular SenVitAL containing enhanced cyan fluorescent protein (ECFP) and venus as FRET pair to improve the FRET efficiency for optical imaging and screening of already developed sensor by our group. The sensor is the improved version of previously reported SenVitAL and consists of ECFP/venus as FRET pair instead of the originally used pair CFP/YFP. To increase the physiological range of vitamin B12 measurement, affinity mutants were created. Compared to the wild type, SenVitAL-5 with W44Q mutation has higher affinity and displayed large dynamic detection range (0.10–480 µM) in response to vitamin B12 binding. For cell-based monitoring and dynamic measurement of vitamin B12 flux rates, SenVitAL-5 was successfully expressed in cytosol of yeast and mammalian cells. Changes in the emission intensities of the two fluorophores were detected using confocal microscopy in both cell types in response to vitamin B12. With the addition of 50 µM extracellular vitamin B12 to the cells, the emission intensity of venus increased and that of ECFP decreased over the time. Furthermore, the results show that the variant SenVitAL-5 measures the vitamin B12 in a concentration-dependent manner, showing the resulting increase in the FRET ratio and thus confirming its utility as an ideal fluorescent indicator for the detection of vitamin B12 in eukaryotic systems in real time. [ABSTRACT FROM AUTHOR]

Cross-linked polydimethylsiloxane (PDMS) films and surfaces obtained by thermal cross-linking of commercially available Sylgard 184 are widely utilized in many areas of science, due to superior thermal stability, low dielectric constant, transparency and biocompatibility. Cross-linked PDMS surfaces are weakly hydrophobic and several experiments, particularly the ones that utilize capillary-driven microscale flow require the modulation of the surface wettability. A well-known strategy to achieve the same is by exposing the Sylgard 184 surface to UV/ozone (UVO) treatment at room temperature. Depending on the duration of exposure, the wettability drops from hydrophobic to a near-complete wetting (water contact angle ~10°), due to the formation of a surface oxide layer. However, under normal atmospheric conditions, these surfaces recover their hydrophobicity over a period of time due to diffusive migration of the uncrosslinked oligomers to the surface, and formation of a hydrophobic dimethyl silicone layer. We explore the hydrophobic recovery process as a function of cross-linker concentration and UVO exposure time and show how a partially or fully recovered PDMS stamp may influence subsequent nanopatterning, including the possible creation of features with different morphology using a single stamp. [ABSTRACT FROM AUTHOR]

Background and objective: Hypertension is not a typical feature of steroid sensitive nephrotic syndrome (SSNS) and the presence of persistent hypertension is suggestive of significant renal lesion. There is paucity of data regarding occurrence and severity of hypertension in SSNS in pediatric population during remission and was the main objective of this study. In addition, correlation with factors like family history, BMI, and lipid profile was studied.Methods: Cross-sectional study conducted at tertiary care center in India including 81 children of infrequent relapsing SSNS between 1 and 10 years in remission and was off steroids. Grading and severity of hypertension were assessed. Statistical analysis was done using SPSS version 21.0.Results: Median age of presentation was 5 years, with male:female ratio of 1.3:1. Out of 81 infrequent relapsing SSNS children, 23.45% (19) had hypertension. Among those children with hypertension (n = 19), 73.68% (14) had positive family history compared to 32.25% (20) in those without hypertension. Positive correlation was found between BP and serum cholesterol and LDL. Of the hypertensive patients, 1 (5.26%) had fundus changes, 2 (10.52%) had features of left ventricular hypertrophy, and 13 (68.42%) had non-nephrotic range proteinuria.Conclusion: There is high incidence of hypertension in NS children during remission. Though significant positive correlation was found with positive family history of hypertension and deranged lipid profile highlighting possibility of essential hypertension in them, there is need for close active monitoring and management of hypertension in them as untreated cases may have significant target organ damage. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterise the peripheral arthritis of spondyloarthritis (pSpA) excluding psoriatic-, inflammatory enteropathy-related, post-infectious reactive-SpA and arthritis associated with axial SpA/ankylosing spondylitis (axSpA/AS). Patients presenting with the clinical features of the broad spectrum of SpA were screened for the presence of peripheral arthritis using the Assessment of SpondyloArthritis International Society (ASAS) criteria. The other conditions that could cause pSpA, e.g. psoriasis, inflammatory enteropathy, reactive arthritis and axSpA/AS, were excluded. Their assessment included clinical, laboratory and imaging features. Of a total of 405 patients seen within the spectrum of SpA, 25 (6.2%) patients were identified as pSpA with none of the conditions that could be attributed to their disease. The male to female ratio was 2.6:1; the pattern of involvement was predominantly lower extremity asymmetrical large joint oligoarthritis in persons below the age of 40 years (60% were <30 years of age). Some had soft tissue and/or extra-articular manifestations characteristic of SpA (36%) and family history (20%) of SpA spectrum of diseases. When compared to peripheral arthritis reported in axial axSpA/AS, root/central joint involvement was minimal in pSpA. Otherwise, the pattern of arthritis appeared similar. Exclusive peripheral arthritis without the presence of the other disease-defining conditions is uncommon, seen only in 6.2% of the SpA spectrum diseases. The pattern of joint involvement was similar to that observed with axSpA/AS except that the root/central joints were not seen. [ABSTRACT FROM AUTHOR]

Wireless network security is becoming a great challenge as its popularity is in the high spirit. On account of open medium, insignificant software implementation, potential for hardware deficits, and improper configuration; Wi-Fi network is vulnerable to Rogue Access Point (RAP). Rogue Access Point is an unauthorized access point which can be installed by end-users without the knowledge of security administrator. When this rogue device is connected to the Internet, it can be used by an assailant to breach the security of the network. Existing RAPs detection techniques have limited capabilities and are not able to detect all variants of assaulters activities. In this paper, a method named Honeypot Intrusion Detection System (Honeypot IDS) is proposed for the detection and prevention of Rogue Access Point via attack detection performed by internal and external malicious users. Honeypot IDS combines Intrusion Detection System and Honeypot, to reduce false alarm rate generated by existing IDS. The proposed approach consist of three phases; filtering, intrusion detection system and honeypot. The traffic after passing filtering and intrusion detection system is rerouted to honeypot for in-depth investigation. The proposed architecture improves the overall performance of the system by diminishing false alarm rate generated by intrusion detection system and is able to sustain the overall workload of honeypot. [ABSTRACT FROM AUTHOR]

Purpose: Maternal brought in dead are the patient who dies in the need of adequate medical care. These deaths are often not analyzed sincerely as they are not institutional deaths. Our aim is to find out actual life threatening cause of delay leading to death. Method: Patients brought dead to casualty were seen by the doctors on duty in Department of Obstetrics and Gynaecology,Gandhi Medical College, Bhopal round the clock. Cause of death was analyzed by verbal autopsy of attendants and referral letter from the institute. In this analytical study a complete evaluation of brought deaths from January 2011 to Decmeber 2014 was done. Results: A total of 64 brought in deaths were reported in this 4 year duration. Most common cause of death was postpartum hemorrhage (54.68 %) followed by hypertension (15.62 %) and the most common cause of delay was delay in getting adequate treatment (56.25 %). Conclusion: The brought in dead are the indicator of the three delays in getting health care. Challenges appear to be enormous to be tackled. Timely management proves to be critical in preventing maternal death. Thus it appears that community education about pregnancy and its complications, EmOC training at FRU and strict adherence to referral protocol may help us to reduce the brought dead burden. [ABSTRACT FROM AUTHOR]

Objective: This study compares the efficacy of sequential clomiphene citrate (CC) + Gonadotropin to that of Gonadotropin alone with ultrasound monitoring. Methods: It is a retrospective analytic study done on a total of 100 couples to compare two groups receiving CC + Gonadotropin and Gonadotropin alone for ovarian stimulation followed by intrauterine Insemination (IUI). We studied the cycle performance parameters. Cumulative pregnancy rates and ovulation rates were the primary outcomes. Results were analyzed following the intention-to-treat principle. Results: There were no significant differences with respect to indications and the numbers of dominant follicles recruited. The endometrial thickness was significantly better in Gonadotropin-alone group ( P < 0.05). Ovulation rate was better for CC + Gonadotropin at 95.91 %. Nine pregnancies were in the CC + Gonadotropin group (18.36 %) and 17 in Gonadotropin-alone group (33.3 %). Conclusions: Significant differences in pregnancy rates and endometrial thickness were seen. Gonadotropin alone thus appears to give better results, but CC + Gonadotropin seems to be a cost-effective drug. [ABSTRACT FROM AUTHOR]

Large-scale systemic mouse phenotyping, as performed by mouse clinics for more than a decade, requires thousands of mice from a multitude of different mutant lines to be bred, individually tracked and subjected to phenotyping procedures according to a standardised schedule. All these efforts are typically organised in overlapping projects, running in parallel. In terms of logistics, data capture, data analysis, result visualisation and reporting, new challenges have emerged from such projects. These challenges could hardly be met with traditional methods such as pen & paper colony management, spreadsheet-based data management and manual data analysis. Hence, different Laboratory Information Management Systems (LIMS) have been developed in mouse clinics to facilitate or even enable mouse and data management in the described order of magnitude. This review shows that general principles of LIMS can be empirically deduced from LIMS used by different mouse clinics, although these have evolved differently. Supported by LIMS descriptions and lessons learned from seven mouse clinics, this review also shows that the unique LIMS environment in a particular facility strongly influences strategic LIMS decisions and LIMS development. As a major conclusion, this review states that there is no universal LIMS for the mouse research domain that fits all requirements. Still, empirically deduced general LIMS principles can serve as a master decision support template, which is provided as a hands-on tool for mouse research facilities looking for a LIMS. [ABSTRACT FROM AUTHOR]

Network security is becoming a great challenge as the popularity of wireless network is increasing. On account of open medium, insignificant software implementation, potential for hardware deficits, and improper configuration; Wi-Fi network is vulnerable to rogue access point (RAP). RAP is an unauthorized access point which can be installed by end-users without the knowledge of security administrator. When this rogue device is connected to the Internet, it can be used by an attacker to breach the security of the network. Attackers can also install RAP to lure other users for sniffing sensitive data. In this paper, a method called 'Shadow Honeynet' has been proposed for the detection and prevention of RAP. The concept of Shadow Honeynet arrives from Shadow Honeypot that integrate the best features of anomaly detection system (ADS) and Honeypot. The shadow is an instance of protected software that share all internal states with the regular ('production') instance of the application to detect potential attacks. The proposed architecture improves the overall performance of the system by diminishing false positives rate generated by ADS and can be able to sustain the overall workload of honeypot. [ABSTRACT FROM AUTHOR]