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Abstract: The direct Bargellini condensation of coumarins involving reaction with chloroform and acetone in the presence of aqueous sodium hydroxide furnished o-carboxyvinylphenoxyisobutyric acids in good yields. The utility of this new useful protocol was demonstrated by the transformation of the three diesters 9b, 9f and 9g to the sesquiterpenes helianane 4, heliannuol A 2 and heliannuol C 3, respectively. [Copyright &y& Elsevier]

Abstract: In order to accommodate large lateral movements, the authors recently developed a new type of steel expansion joint by introducing a bubble in the center of the expansion joint. The lateral movement capacity of the joint was investigated by finite element simulation taking into account both material and geometric non-linearities. The results of the numerical simulations show that the innovative steel bubble joint can accommodate substantially more lateral movements than the conventional steel expansion joint. In this article, the results of the experimental evaluation of the bubble joint are reported. Full scale experiments were carried on three bubble expansion joints: a 2-ft wide joint with a 3-ft high bubble, a 3-ft wide joint with a 3-ft high bubble, and a 3-ft wide joint with a 4.5-ft high bubble. The effectiveness of the new steel bubble expansion joint to undergo large lateral displacements was confirmed by experimental investigations. The experimental results are compared with non-linear finite element simulation results. It is observed that the experimental results agree with the finite element results reasonably well. [Copyright &y& Elsevier]

Abstract: In power, steel, chemical and other industrial plants, ducts are essential to carry air and effluent gases. Ducts are designed such that under the temperature they can expand and contract freely in order to eliminate internal thermal stresses. To allow for free movements, expansion joints are introduced at the points of change in direction and also in long duct runs. Whenever large lateral movements are encountered, either a very deep single expansion joint or a toggle section with two joints is currently used in practice. In this article, a new type of steel expansion joint is proposed by introducing a bubble in the center of the single expansion joint with the goal of increasing its lateral movement capacity. The lateral movement capacity of the proposed joint is investigated by finite element simulation taking into account both material and geometrical nonlinearities. The results show that the new steel bubble joint can accommodate substantially more lateral movements than the conventional steel expansion joint. The new bubble joint provides an economical solution for retrofitting an existing plant where the available space is limited. [Copyright &y& Elsevier]

Abstract: The synthesis of the allelochemical heliannuol C 1 is described by employing a Bargellini condensation and a Claisen rearrangement to install the gem-dimethyl and vinyl functionalities, respectively. A Dieckmann cyclisation of diester 11 enabled the generation of the benzoxepane ring system enshrined in 1. [Copyright &y& Elsevier]

Abstract: Condensation of coumarins with chloroform and acetone in the presence of a base furnished o-carboxyvinylphenoxyisobutyric acids in good yields. The diacid 7a was transformed in a few high yielding steps to the marine sesquiterpene helianane underscoring the importance of this new protocol. [Copyright &y& Elsevier]

Abstract: A total synthesis of the allelochemical heliannuol B 1 is described employing ring closing metathesis to generate the central benzoxepane ring system. [Copyright &y& Elsevier]

• Dengue virus is one of the three most common agents identified in AES. • Existing surveillance for acute encephalitis syndrome (AES) does not include routine testing for dengue. • Dengue accounts for 5% of AES cases in India especially in the absence of laboratory evidence for other pathogens tested. • Testing for dengue in AES cases must be included in routine surveillance. Acute encephalitis syndrome (AES) surveillance in India has indicated that Japanese encephalitis virus (JEV) accounts for 5-35% of AES cases annually; the etiology remains unknown in the remaining cases. We implemented comprehensive AES surveillance to identify other etiological agents of AES, with emphasis on dengue virus. Serum and cerebrospinal fluid (CSF) specimens were collected from patients enrolled prospectively in AES surveillance from 2014-2017 at selected sites of three high burden states of India. All samples were initially tested for JEV IgM. Specimens negative for JEV by serology were tested for IgM to scrub typhus, dengue virus (DEN), and West Nile virus; all JEV IgM-negative CSF samples were tested by PCR for S. pneumoniae, N. meningitidis, H. influenzae , herpes simplex virus type 1, enteroviruses and DEN. Of 10,107 AES patients, an etiology could be established in 49.2% of patients including JEV (16%), scrub typhus (16%) and DEN (5.2%) as the top three agents. Amongst the DEN positive cases (359/6892), seven (2%) were positive only for dengue virus RNA: one in serum and six in CSF. Amongst the pathogens identified, dengue accounted for 5% of all AES cases and was one of the three common etiological agents. These results underscore the importance of including dengue virus in routine testing of AES cases. [ABSTRACT FROM AUTHOR]