Distributed execution of cognitive relaying with time incentive: multiple PU scenario

The prime focus of this study is in developing distributed algorithms for cognitive relaying with time incentive for multiple primary users (CRTI-M). CRTI-M is a symbiotic paradigm in which the incumbent primary users (PUs) of the spectrum, with weak transmission links, seek cooperation from the cognitive secondary user (SU) nodes in their vicinity, and in return reward them with an incentive time for the latter's own communication. When relaying through the SU network, each PU can either use its own spectrum or that of the other PUs. Cross-layer optimization problems are formulated to enable both these possibilities in a multi-hop multi-channel cognitive radio network with the objective of maximizing the cumulative time incentive for the SUs. Corresponding distributed algorithms are developed, which face the challenge of meeting the constraints of the formulated problems with only local information and the lack of a centralized controller. Further, to make the CRTI-M schemes practically realizable, a MAC scheduling protocol is suggested, which gives emphasis to the distributed implementation and provides a unified framework for the PUs and SUs. Simulation results are furnished to demonstrate the effectiveness of the proposed algorithms

Power allocation, bit loading and sub-carrier bandwidth sizing for OFDM-based cognitive radio

The function of the Radio Resource Management module of a Cognitive Radio (CR) system is to evaluate the available resources and assign them to meet the Quality of Service (QoS) objectives of the Secondary User (SU), within some constraints on factors which limit the performance of the Primary User (PU). While interference mitigation to the PU spectral band from the SU's transmission has received a lot of attention in recent literature; the novelty of our work is in considering a more realistic and effective approach of dividing the PU into sub-bands, and ensuring that the interference to each of them is below a specified threshold. With this objective, and within a power budget, we execute the tasks of power allocation, bit loading and sizing the sub-carrier bandwidth for an orthogonal frequency division multiplexing (OFDM)-based SU. After extensively analyzing the solution form of the optimization problems posed for the resource allocation, we suggest iterative algorithms to meet the aforementioned objectives. The algorithm for sub-carrier bandwidth sizing is novel, and not previously presented in literature. A multiple SU scenario is also considered, which entails assigning sub-carriers to the users, besides the resource allocation. Simulation results are provided, for both single and multi-user cases, which indicate the effectiveness of the proposed algorithms in a CR environment

The SS-SCR Scheme for dynamic spectrum access

We integrate the two models of Cognitive Radio (CR), namely, the conventional Sense-and-Scavenge (SS) Model and Symbiotic Cooperative Relaying (SCR). The resultant scheme, called SS-SCR, improves the efficiency of spectrum usage and reliability of the transmission links. SS-SCR is enabled by a suitable cross-layer optimization problem in a multihop multichannel CR network. Its performance is compared for different PU activity patterns with those schemes which consider SS and SCR separately and perform disjoint resource allocation. Simulation results depict the effectiveness of the proposed SS-SCR scheme. We also indicate the usefulness of cloud computing for a practical deployment of the scheme

EVALUATION OF INSECTICIDES AGAINST SUCKING INSECT PESTS INFESTING BT COTTON BG- II

Nine synthetic insecticides were evaluated against sucking insect pests viz., leaf hopper (Amrasca biguttula biguttula Ishida), whitefly (Bemisia tabaci Gennadius), thrips (Thrips tabaci Lindemann) and aphid (Aphis gossypii Glover) in cotton variety RCH-2 Bt (BG-II) during three consecutive years i.e. 2009-10, 2010-11 and 2012-13. Among the different insecticides, imidacloprid 17.8 SL @ 0.008% (7.50 aphid and 1.47 whitefly/ leaf), thiamethoxam 25 WG @ 0.0125% (1.22 leaf hopper/ leaf) and diafenthiuron 50 WP @ 0.05% (1.43 thrips/ leaf) found more effective and safer to the natural enemies viz., Chrysoperla carnea (adult), spiders and coccinellids (grubs and adult). Highest seed cotton yield (30.81 q/ha) was harvested from crop treated with imidacloprid followed by clothianidin (27.34 q/ha), difenthiuron (26.93 q/ha), thiamethoxam (26.01 q/ha) and acetamiprid (25.68 q/ha). The highest Insecticidal Cost Benefit Ratio (1: 16.54) was registered in imidacloprid followed by acetamiprid (11.06), acephate (10.38), thiamethoxam (7.05) and difenthiuron (6.13)

Study of metastasis in lymph node by fine needle aspiration cytology: our institutional experience

Background:Fine needle aspiration cytology (FNAC) is a reliable as well as an inexpensive diagnostic method. It is suitable for the developing countries for the diagnosis of lymphadenopathy at any approachable site. Fine needle aspiration cytology not only confirms the presence of metastatic disease but also, in most cases, gives the clue regarding the origin of the primary tumor, prognosis as well in the management of patient for staging purposes. The aim of the study was to detect and diagnose metastasis in lymph nodes. Methods:A study was done of all metastatic lymph node lesions reported in Department of Pathology, Govt. Medical College, Surat from May 2011 to April 2012.Results:A total of 2355 cases of fine needle aspiration cytology were carried out of which 580 cases were of lymph node. Cytology results were positive for metastasis in 157 specimens (27.06%). The most common site was cervical lymph nodes. Maximum numbers of cases of metastatic tumors were in 41-50 yrs age group. There were 115 males and 42 females with a male predominance (Male:Female= 2.8:1). The most common malignancy was squamous cells carcinoma, seen in 118 cases (75.15%), followed by metastatic mammary carcinoma (13 cases, 8.29%). In 26 cases out of 580 cases, histopathological confirmation was done and diagnostic accuracy of FNAC was 100%. Conclusions:Fine needle aspiration cytology of lymphadenopathy is a useful tool in diagnosing metastatic lesions with good certainty

SWOG 1815: A phase III randomized trial of gemcitabine, cisplatin, and nab-paclitaxel versus gemcitabine and cisplatin in newly diagnosed, advanced biliary tract cancers

Background: Biliary tract cancers (BTCs) are a heterogeneous group of malignancies with a dismal prognosis. Gemcitabine-based regimens are the standard of care in advanced disease, but median overall survival (OS) is roughly 12 months. The addition of albumin-bound paclitaxel to gemcitabine and cisplatin (GAP) demonstrated promising efficacy in a 60 patient, single-arm phase II study (Shroff et al, JAMA Oncol 2019), with observed median OS of 19.2 months. Methods: SWOG 1815 is a randomized, open-label, phase III trial comparing GAP to gemcitabine/cisplatin (GC). The study included newly diagnosed advanced BTC patients (pts), randomized 2:1 to GAP vs. GC. GAP included gemcitabine at 800 mg/m2, cisplatin at 25 mg/m2 and albumin-bound paclitaxel at 100 mg/m2 on days 1 and 8 of a 21-day cycle. GC included standard dosing of gemcitabine at 1000 mg/m2 and cisplatin at 25 mg/m2 on days 1 and 8 of a 21-day cycle. Pts were treated until progression. The primary endpoint was overall survival (OS) with a target hazard ratio of 0.7 with 90% power and a 1-sided alpha of 0.025; randomization was stratified by disease site (intrahepatic cholangiocarcinoma [CCA] vs gallbladder adenocarcinoma [GBC] vs extrahepatic CCA), disease stage (locally advanced vs metastatic), and Zubrod PS 0 vs 1. Results: Of 441 eligible pts randomized, 55% were female. 67% of patients had intrahepatic CCA, 16% had GBC and 17% had extrahepatic CCA. Most pts had metastases (73%). Median OS with GAP vs. GC was 14 vs. 12.7 mo respectively (HR 0.93, 95% CI 0.74-1.19, p=0.58), ORR (confirmed and unconfirmed) 34% vs25% (p=0.11) and median PFS 8.2 vs 6.4 mo (HR 0.92, 95% CI 0.72-1.16, p=0.47), respectively. Grade 3 and 4 treatment related adverse events (TRAEs) in ≥10% of pts for GAP and GC were anemia, neutropenia, and thrombocytopenia. GAP had more ≥ grade 3 hematologic AEs compared to the GC arm (60% vs. 45%, p=0.003). Discontinuation due to toxicity was at 24% vs 19% (p=0.26) with GAP vs GC. In exploratory subset analyses, GAP vs GC improved OS in pts with locally advanced disease (medians 19.2 vs 13.7 mo; HR 0.67, 95% CI 0.42- 1.06, p=0.09) and in GBC pts (medians 17.0 vs 9.3 mo; HR 0.74, 95% CI 0.41-1.35, p=0.33). ORR for GAP vs GC in GBC was 50% vs 24% (p=0.09) and for locally advanced disease 28 vs 21% p=0.74. Conclusions: SWOG 1815 did not result in a statistically significant improvement in median OS with GAP vs. GC. The GAP regimen had higher rates of TRAEs without a statistically significant difference in discontinuation rates. Pts with locally advanced disease and GBC may benefit from the use of GAP. Further analyses are ongoing to understand potential benefit of GAP in subsets of BTC pts. Funding: NIH/National Cancer Institute grants CA180888, CA180819, CA180820, CA180821, and CA180868; and in part by Celgene Corporation, Summit, NJ (subsidiary of Bristol Myer Squibb)

High salt-tolerant protease from a potential biocontrol agent bacillus pumilus M3-16

In this paper, we investigate the characterization and evaluation of the antifungal protease activity from a halotolerant strain M3-16 of Bacillus pumilus, earlier isolated from a shallow salt lake in Tunisia. Protease enzyme was highly induced by the pathogen tested in vitro (27.4 U/ml). This is the first report on high salt-tolerant protease from B. pumilus, since it was active at high salinity (from 5 to 30% NaCl, w/v) as well as in the absence of salinity. This enzyme showed optimal activity at 60 °C and pH 8. At 80 °C and 30 min, the enzyme retained up to 91% and it showed stability over a wide pH range (from pH 5 to 11). The enzyme was found to be monomer with an estimated molecular mass of 31 kDa. The amino acid sequence showed high similarity (94%) to ATP-dependent protease from B. pumilus strain ATCC 7061. Thus, our alkaline thermostable and high salt-tolerant protease induced by a phytopathogenic fungus, could be useful for application in diverse areas such as biotechnology alimentary and agronomy industries

Susceptibility testing of filamentous fungi to amphotericin B by a rapid radiometric method

A rapid, radiometric method was developed to determine the susceptibility of filamentous fungi to amphotericin B. The rapid, radiometric method depended on measurement of the inhibition of 14CO2 production in the presence of amphotericin B. Thirty isolates of filamentous fungi were tested by the rapid, radiometric method and a reference agar dilution method. There was 93% agreement between the two methods when an 80% or greater decrease in CO2 production was used to calculate the minimal inhibitory concentration with the rapid, radiometric method. Minimal inhibitory concentrations, based on 80% decrease of CO2 production, were achieved within 24 h of incubation with all of the fungi tested.</jats:p