Herein we report a transition metal free catalytic terminal alkyne functionalization across the C-X triple bond (X = CH and N) with
E
-selective homo (alkyne-alkyne) and head-to-tail selective hetero ...(alkyne-nitrile) dimerization. A series of stoichiometric reactions enabled us to crystallize a reactive organometallic intermediate K-arylacetylide complex which was characterized by X-ray crystallography, indicating that an ionic mechanism is operative.
E
-Selective alkyne-alkyne dimerization as well as terminal alkyne functionalization across the C-N triple bond under transition metal free conditions at room temperature was accomplished.
Nickel perfluoroethyl and perfluoropropyl complexes supported by naphthyridine-type ligands show drastically different aerobic reactivity from their trifluoromethyl analogs resulting in facile oxygen ...transfer to perfluoroalkyl groups or oxygenation of external organic substrates (phosphines, sulfides, alkenes and alcohols) using O
2
or air as a terminal oxidant. Such mild aerobic oxygenation occurs through the formation of spectroscopically detected transient high-valent Ni
III
and structurally characterized mixed-valent Ni
II
-Ni
IV
intermediates and radical intermediates, resembling O
2
activation reported for some Pd dialkyl complexes. This reactivity is in contrast with the aerobic oxidation of naphthyridine-based Ni(CF
3
)
2
complexes resulting in the formation of a stable Ni
III
product, which is attributed to the effect of greater steric congestion imposed by longer perfluoroalkyl chains.
Aerobic oxidation of long-chain perfluoroalkyl Ni complexes results in O-atom transfer to form perfluorocarboxylates
via
high valent Ni; in the presence of external substrate, oxygenation of phosphines, sulfides, stilbenes or alcohols occurs.
Designing parallel graph algorithms on GPUs has been challenging. We observe three limitations with the existing work. First, algorithms often rely on only one of the strategies to propagate ...information: push or pull. We observe that neither is an optimal choice in many cases. Second, the cost of updating the underlying data structures per iteration is high. This results in a significant performance overhead. Third, considering the in-herent irregularity of graph processing, one-size-fits-all approach is too rigid for different types of graphs. In this work, we address these shortcomings by improving the processing of an existing graph framework, Subway. In particular, we propose a novel technique in terms of amalgamating the two propagation strategies (push and pull) into a hybrid traversal strategy. In this, the vertices of the graph propagate their information by pulling the information from the neighbours, performing a local computation, and subsequently pushing the result to all the neighbours, all within an iteration. We propose to reuse the SubCSR structure in Subway across a few iterations to significantly reduce the computational overhead, but without compromising the correctness or efficiency of the algorithm. Furthermore, we explore heuristics on when to use push, pull, or hybrid traversal strategies. We illustrate the effectiveness of our three-pronged approach by applying it to four popular graph algorithms: Connected Components (CC), Single-Source Shortest Path (SSSP), Breadth First Search (BFS) and Page Rank (PR) on an NVIDIA GeForce RTX 3060 GPU. Our extensive experimental evaluation on GeForce RTX 3060 GPU reveals that the proposed hybrid approach with adaptive heuristics and approximate subCSR computation is effective in reducing the execution time of CC, SSSP, and PR by 31 %, 7.56%, and 6.43% respectively, compared to the minimum of push or pull algorithm that uses subCSR structure.
Emerging evidence indicates that lysosome function extends beyond macromolecular degradation. Genetic and functional defects in components of the lysosomal transport machinery cause lysosomal storage ...disorders implicating the lysosomal solute carrier (SLC) transporters as essential to vital cell processes. The pathophysiology and therapeutic potential of lysosomal SLC transporters are highlighted here, focusing on recent discoveries in autophagic amino acid sensing (SLC38A9), phagocytic regulation in macrophages (SLC29A3, SLC15A3/A4), adenosine triphosphate (ATP) exocytosis in neurotransmission (SLC17A9), and lysosomal transport of maytansine catabolites into the cytoplasm (SLC46A3).
Drug transporter research conducted over the last several decades has led to a greatly advanced understanding of the mechanisms underlying the principles of drug absorption and disposition. Although ...many transporters remain poorly characterized, there is ample evidence that the drug transporter field will ultimately provide vital support to routine patient management, and will play a key role in the discovery, development, and evaluation of innovative, cutting‐edge therapies.
Fleas (Insecta, Siphonaptera) are important vectors of plague and murine typhus in many parts of the world. Currently, about 2700 flea species were described in the world. The most common vector flea ...Xenopsylla cheopis is found throughout India, but X. astia, and X. brasiliensis are found less and limited in distribution associated with the domestic rats such as Rattus rattus, R. norvegicus, Mus musculus, and Bandicota bengalensis. Bubonic plague is a major flea-borne disease caused by the bacterial pathogen Yersinia pestis, transmitted from rats to humans via the rodent flea, X. cheopis. A major outbreak of plague and high mortality occurred in India. After 1966 with the 3 decadal intervals, plague cases occurred only during the year 1994 reported in 5 different states (Gujarat, Maharashtra, Karnataka, Uttar Pradesh, Madhya Pradesh and New Delhi and subsequently plague cases occurred during 2002 and 2004 after the one-decade interval in Himachal Pradesh (2002). Another outbreak of bubonic plague was reported in Dangud village, Barkhot tehsil, Uttarkashi district, Uttarakhand during October 2004. Ctenocephalides fleas are common in cats and dogs, which are the main vectors of bacteria rickettsiae, such as Rickettsia typhi, R. felis, R. conorii, and Bartonella henselae. Molecular and serological evidence also confirms the presence of R. typhi, R. conorii R. felis and B. henselae pathogens in cats and other fleas in India. Flea bites and flea-borne dermatitis are common in men and pet animals. Because of the re-emergence of the plague, updated information on fleas and flea-borne diseases are essential to control the flea vectors and flea-borne diseases in India. Hence, this comprehensive review updates the available information on fleas and fleas transmitted diseases in India.
Mites act as the vectors of zoonotic vector-borne disease scrub typhus caused by the rickettsial pathogen Orientia tsutsugamushi. In India, scrub typhus is transmitted by the mite Leptotrombidium ...deliense. Rodents are the reservoirs and support the spread of this disease. Sarcoptes scabiei or the itch mite is causing scabies which is a common skin infection in India. Dermatitis, trombiculosis, and mite dust allergy are common mite-borne diseases transmitted by Pyemotidae family. D. brevis folliculorum and Demodex brevis are two major mite species found on humans also causing a disease; "Demodicosis", common in India. Dermanyssus gallinae, fowl mite causes pruritis in poultry birds, transmits infections to poultry workers when they come into contact with birds. There is a re-emergence of mite-borne diseases, especially scrub typhus, in many parts of India requiring urgent attention for its control. This review is aimed to update the available information on mites and mite transmitted diseases prevalent in India to highlight the importance of rodent and chigger mite vector control to prevent forthcoming mite-borne diseases in India.
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