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Chromatography is a widely used analytical tool for separating a mixture of compounds into individual component. High performance liquid chromatography (HPLC) is one of the most important methods used for the separation, identification and quantification of a compounds present in a mixture. It meets many criteria of analysis but its main drawbacks are it is relatively time consuming to run a chromatogram and consumes high amount of solvent compared to other analytical methods. There is a need to develop a method which can overcome these drawbacks of HPLC. Ultra performance liquid chromatography (UPLC) is the new approach which opens novel direction in the field of liquid chromatography. It works on similar principle but shows better performance than conventional HPLC. UPLC is a technique of liquid chromatography with improved runtime and sensitivity with less than 2 μm particle size. The UPLC separation process is carried out under very high pressure (up to100 MPa). Additionally, it reduces the cost of reagent with shorter run time as compared to conventional HPLC. This article updated until 2020, provides a general review on the principle, instrumentation and application of UPLC in different fields of science. [ABSTRACT FROM AUTHOR]

The notion of ideals is introduced in transitive BE-algebras. Some characterization theorems of ideals of transitive BE-algebras are derived. The notion of semi-ideals is introduced and studied a relationship between semi-ideals and ideals. Properties of ideals are studied with the help of homomorphisms and congruences. [ABSTRACT FROM AUTHOR]

The concept of generalized prime D-filters is introduced in distributive lattices. Generalized prime D-filters are characterized in terms of principal filters and ideals. The notion of generalized minimal prime D-filters is introduced in distributive lattices and properties of minimal prime D-filters are then studied with respect to congruences. Some topological properties of the space of all prime D-filters of a distributive lattice are also studied. [ABSTRACT FROM AUTHOR]

In this paper, an innovative compact pattern reconfigurable antenna is proposed and developed to establish an inter-satellite communication link between the Formation flying spacecraft. The reconfigurable beam switching antenna comprises a driven Monopole at the center, encompassed with four Reconfigurable Selective Reflectors (RSR) which act as RF radiators and reflectors for different switching conditions. PIN diodes are used to electronically control the switch states of RSR and beam switching is achieved with uniform gain along the azimuth plane without affecting the antenna's overall performance. The peculiar demands of Formation Flying Mission (FFM) satellites such as small size and low power for communication system are resolved by the proposed technique where a single antenna with different patterns communicates with multiple satellites reducing the antenna space and power consumption. Furthermore, it also offers a solution to the problem encountered in existing FFM antenna, like microstrip patch, which serves only one satellite at a time. The antenna is designed at 2.45GHz center frequency. Simulated results show good impedance matching and performance with 13 to 15% bandwidth and wide beamwidth. The experimental validation shows that the simulation results of the antenna agree well with the measured results. [ABSTRACT FROM AUTHOR]

C4‐C5 periannulation of 1‐naphthols and ynones via BF3.Et2O mediated one‐pot cascade under metal and solvent‐free conditions have been developed for the synthesis of perinaphthenones. Furthermore, this strategy features the formation of new periannulation at C4‐C5 positions of α‐naphthol, synthesis of highly substituted perinaphthenones, broad substrate scope, readily available starting materials and good to moderate yields. The perinaphthenones products synthesized here have exhibited interesting photo physical properties [ABSTRACT FROM AUTHOR]

Some properties of prime D-filters of distributive lattices are studied with respect to the direct products and set-theoretic intersection. Properties of minimal prime D-filters of distributive lattices are studied. Some topological properties of the space of all minimal prime D-filters of a distributive lattice are studied. Finally, it is showed that the space of all minimal prime D-filters of a distributive lattice is a Hausdorff space. [ABSTRACT FROM AUTHOR]

This paper investigates the load frequency analysis (LFC) of two area interconnected realistic power system with multi-fuel generating units. Each area consists of thermal, hydro and gas power generating plants. A new evolutionary algorithm is proposed, named Hybrid artificial electric field (HAEFA) optimization algorithm and integral square error (ISE) performance index is utilized to find classical PI/PID controller gains. Later, total analysis is carried out in presence of PID an account of its superiority functioning rather than PI. Moreover, the efficacy of the presented algorithm is deliberated by testing on two area conventional power system model of thermal unit with structure of non-reheat turbines and also on sphere benchmark function. As the load variation is dynamic in nature, mitigating the area frequency fluctuations and tie-line power variations could not been fulfilled by primary regulator and secondary controller. Effective governing needs additional devices. Therefore, superconducting magnetic energy storage (SMES) devices are incorporated in both areas in addition to Thyristor controlled series capacitor (TCSC) is connected in tie-line. Results, shows the system performance has been significantly improved with SMES and TCSC in the presence of HAEFA based PID controller. The potency of the HAEFA algorithm is compared with other optimizations covered in literature. [ABSTRACT FROM AUTHOR]

The outlier detection technique is widely used in the data analysis for the clustering of data. Many techniques have been applied in the outlier detection to increase the efficiency of the data analysis. The Local Projection based Outlier Detection (LPOD) method effectively identifies neighbouring values of data, but this has the drawback of random selection of the cluster centre that affects the overall clustering performance of the system. In this study, the Adaptive Clustering by Fast Search and Find of Density Peak (ACFSFDP) is proposed to select the clustering centre and density peak. This ACFSFDP method is implemented with the min-max algorithm to find the number of categories that measured the local density and distance information. The density and distance are used to select the cluster centre, but density is not calculated on the existing distance based clustering techniques. The ACFSFDP method calculates cluster centre based on the density and distance during the clustering process, whereas the existing techniques randomly select the data centre. The results indicated that the ACFSFDP method is provided effective outlier detection compared with existing Clustering by Fast Search and Find of Density Peak (CFSFDP) methods. The ACFSFDP is tested on two datasets Pen-digits and waveform datasets. The experiment results proved that Area Under Curve (AUC) of the ACFSFDP is 99.08% on the Pen-Digit dataset, while the existing distance classifier method k-Nearest Neighbour has achieved 68.7% of AUC. [ABSTRACT FROM AUTHOR]

The notion of -filters is introduced on the lines of a dual annihilator of commutative BE-algebras. An equivalent condition is given for a proper ω-filter of a commutative BE-algebra to become a prime filter. A characterization theorem of ω-filters is established which in turn establishes some of equivalent conditions for a prime filter of a commutative BE-algebra to become an ω-filter. It is proved that every ω-filter is an intersection of all minimal prime filters. [ABSTRACT FROM AUTHOR]

The concept of radicals of ideals is introduced in BE-algebras and certain properties of these radicals are derived in terms of direct products and homomorphisms. The notion of semi-maximal ideals is introduced in BE-algebras through the radical of ideals and their significant properties are investigated. Some equivalent conditions are derived for every semi-maximal ideal to become a maximal ideal. [ABSTRACT FROM AUTHOR]

Acute appendicitis is one of the most common abdominal surgical emergencies. Obstruction of the appendix caused by lymphoid hyperplasia and fecaliths is considered to be the most common cause of [...], Perivascular epithelioid cell tumors (PEComas) are a group of mesenchymal tumors that coexpress melanocytic and smooth muscle markers; their exact origin remains unknown. This group includes renal angiomyolipoma, clear cell sugar tumor, and lymphangioleiomyomatosis, although the term perivascular epithelioid cell tumors is currently used for lesions that exhibit a similar morphologic and immunohistochemical profile throughout the human body. Recently, a distinct subset of PEComas has been shown to harbor transcription factor E3 gene (TFE3) fusions. We report, for the first time, a unique case of TFE3-positive PEComa presenting as acute appendicitis in a 24-year-old woman. Microscopically, the tumor was composed of benign-appearing epithelioid cells with clear and eosinophilic cytoplasm, and arranged in nested and alveolar patterns. Immunohistochemical studies showed diffuse strong positivity for neuron-specific enolase, TFE3, and progesterone receptor and focal strong positivity for human melanoma black--15 (HMB-45) and melanocyte differentiation antigen (Melan-A) in the tumor cells. Although rare, PEComa should be included in the differential diagnosis of mesenchymal tumors of the appendix. (Arch Pathol Lab Med. 2013;137:434-437; doi: 10.5858/arpa.2012-0103-CR)

Chronic inflammation is a well-recognized risk factor for human cancer development, and at least one-third of all human cancers have been associated with inflammation, for example, long-standing chronic inflammatory bowel [...], * Context.--Inflammatory bowel disease (IBD) is a longstanding chronic active inflammatory process in the bowel with increased risk for the development of colorectal carcinoma. Several molecular events involved in chronic active inflammatory processes contribute to multistage progression of human cancer development, including reactive oxygen and nitrogen species, aberrant arachidonic acid metabolites and cytokines/growth factors, and immune dysfunction. These molecular events in IBD lead to genetic abnormality and promote aberrant cell proliferation, which further lead to epithelial changes encompassing a broad spectrum from inflammation-induced hyperplasia to dysplasia. Objective.--To review the (1) epidemiologic and molecular pathogenesis of the risk for colorectal cancer in IBD, (2) morphologic characterization, biomarker(s), and classification of dysplastic lesions, and (3) clinical management of dysplastic lesions arising in IBD. Data Sources.--The different IBD-related dysplastic lesions are illustrated by using morphology in conjunction with molecular pathways, and the 'field cancerization' theory and its potential significance are discussed with a review of the literature. Conclusions.--Patients with IBD are at increased risk of developing colorectal cancer. The risk of developing carcinoma is related to the extent/duration/activity of the patient's disease. There is no consensus regarding the extent of carcinoma risk associated with IBD; however, all would agree that patients with IBD represent a group at significant risk for developing carcinoma and as such, warrant adequate surveillance and prevention. With better screening modalities and detection/characterization of dysplastic lesions, IBD-associated serrated lesions, and 'field cancerization,' we will improve our understanding of and approach to risk stratification. (Arch Pathol Lab Med. 2013;137:338-350; doi: 10.5858/arpa.2012-0086-RA)

The cloning of corresponding alkaline phosphatase gene (phoK) from Sphingomonas sp. strain BSAR-1, its overexpression in Escherichia coli and application in the bioprecipitation of uranium from alkaline solution are described. The studies have shown the potential utility of genetically engineering PhoK for the bioprecipitation of uranium from alkaline solutions.