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Similar to graphene and fullerene, metal-doping has been considered to be an effective approach to the construction of highly stable boron clusters. In this work, a series of actinide metal-doped boron clusters AnB

Hole doping and biaxial tensile strain on T-graphene can increase its superconducting Tc to a value higher than those of the pristine T-graphene and many other 2D carbon-based superconductors.

Recently, the observation of the first axially chiral borospherenes (B39−) enriched the members of the boron cluster family, and opened the door to axially chiral boron cages. Herein, we theoretically predicted a series of chiral borospherenes by actinide metal (An) encapsulation, which are new chiral members of the borospherene family. Theoretical calculations demonstrate that the C2 neutral and charged Ac– and Th–B39 boron clusters (Ac@B39, [Ac@B39]2+, and Th@B39, [Th@B39]3+) are the most stable structures, and each borospherene possesses degenerate enantiomers, in accordance with the chiral borospherenes B39−. In contrast, the global minimum structures of Cf embedded borospherenes have no symmetry (C1). All the chiral actinoborospherenes [An@B39]n+ (An = Ac, n = 0, 2; An = Th, n = 0, 3) possess high formation energies, especially C2 [Th@B39]3+. Bonding analysis shows that each complex of [Ac@B39]n+ and [Th@B39]n+ has the characteristic of σ + π double delocalization, and the Th–B bonds possess relatively higher covalency than the Ac–B bonds, resulting in the higher formation energy of C2 [Th@B39]3+. Therefore, the covalent character of An–B bonding may be essential for the formation of these chiral actinoborospherenes. This work extends the chiral borospherenes to actinide metal-doped chiral borospherenes, and sheds light on the design of chiral metalloborospherenes.

The exploration of metal-doped boron clusters has a great significance in the design of high coordination number (CN) compounds. Actinide-doped boron clusters are probable candidates for achieving high CNs. In this work, we systematically explored a series of actinide metal atom (U, Np, and Pu) doped B20 boron clusters An@B20 (An = U, Np, and Pu) by global minimum structural searches and density functional theory (DFT). Each An@B20 cluster is confirmed to be a twenty-coordinate complex, which is the highest CN obtained in the chemistry of actinide-doped boron clusters so far. The predicted global minima of An@B20 are tubular structures with actinide atoms as centers, which can be considered as boron molecular drums. In An@B20, U@B20 has a relatively high symmetry of C2, while both Np@B20 and Pu@B20 exhibit C1 symmetry. Extensive bonding analysis demonstrates that An@B20 has σ and π delocalized bonding, and the U-B bonds possess a relatively higher covalency than the Np-B and Pu-B bonds, resulting in the higher formation energy of U@B20. Therefore, the covalent character of An-B bonding may be crucial for the formation of these high CN actinide-centered boron clusters. These results deepen our understanding of actinide metal doped boron clusters and provide new clues for developing stable high CN boron-based nanomaterials.

Background Malaria around the China-Myanmar border is a serious health problem in the countries of South-East Asia. An. minimus is a principle malaria vector with a wide geographic distribution in this area. Malaria is endemic along the boundary between Yunnan province in China and the Kachin State of Myanmar where the local Anopheles community (species composition) and the malaria transmission vectors have never been clarified. Methods Adult Anopheles specimens were collected using CDC light traps in four villages along the border of China and Myanmar from May 2012 to April 2013. Morphological and molecular identification of mosquito adults confirmed the species of Anopheles. Blood-meal identification using the female abdomens was conducted using multiplex PCR. For sporozoite detection in An. minimus, sets of 10 female salivary glands were pooled and identified with SSU rDNA using nested PCR. Monthly abundance of An. minimus populations during the year was documented. The diversity of Anopheles and the role of An. minimus on malaria transmission in this border area were analyzed. Results 4,833 adult mosquitoes in the genus Anopheles were collected and morphologically identified to species or species complex. The Anopheles community is comprised of 13 species, and 78.83% of our total specimens belonged to An. minimus s.l., followed by An. maculatus (5.55%) and the An. culicifacies complex (4.03%). The quantity of trapped An. minimus in the rainy season of malaria transmission was greater than during the non-malarial dry season, and a peak was found in May 2012. An. minimus fed on the blood of four animals: humans (79.8%), cattle (10.6%), pigs (5.8%) and dogs (3.8%). 1,500 females of An. minimus were pooled into 150 samples and tested for sporozoites: only 1 pooled sample was found to have sporozoites of Plasmodium vivax. Conclusion Anopheles is abundant with An. minimus being the dominant species and having a high human blood index along the China-Myanmar border. The sporozoites in An. minimus were determined to be Plasmodium vivax with a 0.07-0.7% infection rate.

To study the clinicopathologic features of peripheral T-cell lymphoma, unspecified (PTL-U) with follicular pattern.The clinical data, hematoxylin and eosin-stained sections of lymph node biopsies and follow-up data of 18 cases of PTL-U associated with follicular growth pattern were reviewed and studied. Eight cases of reactive lymphoid hyperplasia were used as controls. Semi-quantitative observation by retiform micrometer rule was carried out. Immunohistochemical study was also performed in all cases. T-cell receptor and immunoglobulin heavy chain gene rearrangement studies were conducted by polymerase chain reaction-based method.The median age of the patients was 53 years. The male-to-female ratio was 1.57:1 in lymphoma group. All of the lymphoma patients presented with superficial lymphadenopathy, with (8/18) or without B symptoms. Histologically, the lymphoma was characterized by follicles of various sizes and shapes. The T zones were expanded by medium-sized lymphoma cells which contained clear cytoplasm and irregular nuclei. Mitotic figures were commonly identified. Immunohistochemical study confirmed that the lymphoma cells were of T-lineage. The proliferative index, as highlighted by Ki-67, was higher [average = (38.24 +/- 13.42)%/mm2] than that in the control group. T-cell receptor gene rearrangement was demonstrated in 71.4% (10/14) of the lymphoma cases.A definitive diagnosis of PTL-U with follicular pattern can be made on the basis of morphologic examination, immunohistochemical assessment and clinical features. Cases with atypical features can further be delineated by molecular analysis. Long-term follow up of these patients is prudent.

Delia antiqua is a major underground agricultural pest widely distributed in Asia, Europe and North America. In this study, we sequenced and annotated the complete mitochondrial genome of this species, which is the first report of complete mitochondrial genome in the family Anthomyiidae. This genome is a double-stranded circular molecule with a length of 16,141 bp and an A+T content of 78.5%. It contains 37 genes (13 protein-coding genes, 22 tRNAs and 2 rRNAs) and a non-coding A+T rich region or control region. The mitochondrial genome of Delia antiqua presents a clear bias in nucleotide composition with a positive AT-skew and a negative GC-skew. All of the 13 protein-coding genes use ATN as an initiation codon except for the COI gene that starts with ATCA. Most protein-coding genes have complete termination codons but COII and ND5 that have the incomplete termination codon T. This bias is reflected in both codon usage and amino acid composition. The protein-coding genes in the D. antiqua mitochondrial genome prefer to use the codon UUA (Leu). All of the tRNAs have the typical clover-leaf structure, except for tRNA Ser(AGN) that does not contain the dihydrouridine (DHU) arm like in many other insects. There are 7 mismatches with U-U in the tRNAs. The location and structure of the two rRNAs are conservative and stable when compared with other insects. The control region between 12S rRNA and tRNA Ile has the highest A+T content of 93.7% in the D. antiqua mitochondrial genome. The control region includes three kinds of special regions, two highly conserved poly-T stretches, a (TA)n stretch and several G(A)nT structures considered important elements related to replication and transcription. The nucleotide sequences of 13 protein-coding genes are used to construct the phylogenetics of 26 representative Dipteran species. Both maximum likelihood and Bayesian inference analyses suggest a closer relationship of D. antiqua in Anthomyiidae with Calliphoridae, Calliphoridae is a paraphyly, and both Oestroidea and Muscoidea are polyphyletic.