To determine if genetic diversity of Blastocystis hominis exists in China, 35 B. hominis isolates obtained from 19 asymptomatic infected individuals and 16 patients with gastrointestinal symptoms were genotyped by PCR using seven pairs of known sequenced-tagged site (STS) primers. Out of the 35 isolates, 29 were identified as one of the known genotypes, while five isolates showed two distinct genotypes, and one isolate was an unknown genotype as this was negative with all the STS primers. In this study, none of the isolates was classified as subtypes 4-7. Compared with the spectrum of human B. hominis subtypes obtained from five geographically different countries (Japan, Pakistan, Bangladesh, Germany, and Thailand), these results showed that subtype 1 was more a popular genotype (18/35) in China. In addition, two groups of the isolates from 19 asymptomatic infected individuals and those from 16 patients with intestinal symptoms were compared with the PCR-based subtype classification. The results suggest a possible relationship between subtype 1 and a pathogenic potential of this parasite.

Blastocystis has a widespread distribution in a variety of animals, which is a potential source of infection for humans. Previous studies show that Blastocystis sp. subtypes 1-4, 6, and 7 were composed of isolates from humans and animals, while Blastocystis sp. subtype 5 included only pig and cattle isolates. A more recent study on the basis of the SSU rDNA sequence has showed that a single Blastocystis isolate amplified directly from the faeces of a Thai human belongs to Blastocystis sp. subtype 5, but that study failed to cultivate this isolate. We report herein two human isolates from in vitro cultures belonging to Blastocystis sp. subtype 5 and one human isolate from in vitro culture containing two distinct genotypes of Blastocystis sp. subtypes 3 and 5 using PCR amplification with seven kinds of sequence-tagged site (STS) primers. Additionally, 16 Blastocystis isolates from pigs living in the same rural area with the three humans infected Blastocystis sp. subtype 5 were also genotyped by PCR with the STS primers, and all isolates from pigs and humans were compared by small-subunit ribosomal RNA (SSU rRNA) restriction-fragment-length polymorphism (RFLP) analyses using two restriction endonucleases (HinfI and RsaI). The results indicated that all of the isolates from pigs showed Blastocystis sp. subtype 5 and the RFLP patterns of all of the isolates from humans except for the mixed one were identical or quite similar to those of the 16 pig isolates with both HinfI and RsaI enzymes. These findings provide additional molecular-based evidence supporting the zoonotic potential of Blastocystis sp. subtype 5. This study also showed that Blastocystis sp. subtype 3 overgrew Blastocystis sp. subtype 5 in vitro.

Identifying applicable anode materials is a significant task for Li-and Na-ion battery (LIB and NIB) technologies. We propose the GaN monolayer (2D GaN) can be a good anode candidate. The GaN monolayer manifests stable Li/Na adsorption and inherently low theoretical voltages. Most excitingly, both high storage capacity and extremely fast Li/Na diffusion can be simultaneously realized in the GaN monolayer. For Li, the storage capacity and diffusion barrier is 938 mA h g -1 and 80 meV , respectively.And the values for Na are 625 mA h g -1 and 22 meV. Comparing with known 2D anode materials with similar scale of ion diffusion barriers, the GaN monolayer almost possesses the highest Li/Na storage capacity discovered to date. Our work suggests that the 2D GaN is a prospective anode material offering fast ion diffusion and high storage capacity.The Li-ion batteries (LIBs) have been intensively used nowadays. The success of LIBs mainly benefits from their excellent energy conversion efficiency and good storage capacity. 1-5 Nevertheless, the development of LIBs has currently faced increasing challenge due to the naturally limited lithium resource and their high production cost. [6][7][8] As a result, non-Li-ion batteries have emerged in recent years. 9-15 Among them, Na-ion batteries (NIBs) have attracted the most attentions. 9,10 This arises from that the sodium has relatively low cost. For LIBs and NIBs, the electrochemical performance is the most dependent on their electrode materials; thus developing good electrode materials is one of major focuses in current battery technologies. Two-dimensional (2D) materials have offered great potential as ion battery electrodes, because their fully exposed surfaces are believed to provide fast ion diffusion and the maximum ion insertion channels. [16][17][18] Up to date, several families of 2D materials, such as graphene, [19][20][21] MXenes, [22][23][24][25][26][27][28] transition-metal dichalcogenides (TMDCs), 29-32 transition-metal dinitrides (TMDNs), 33 borophenes, 34-36 and others [37][38][39][40] have been identified as LIBs and NIBs electrodes. For battery electrode materials, the ion diffusion speed and the storage capacity are two of the most crucial indicators for the electrode performances. However, most known 2D electrode materials can only achieve high performance on one of these indicators. 2D anode materials, for example, Mo 2 C, 24,25 Nb 2 C 26 and Ti 3 C 2 23 are proposed to offer very fast Li/Na diffusion speed but have low or moderate storage capacities; silicence 41 and β 12 /χ 3 Borophene 35 show extremely high Li/Na storage capacities but have poor ion diffusion speed. Thus there is urgent need to explore excellent electrode materials which can offer fast ion diffusion and high storage capacity simultaneously.As a well-known semiconductor, GaN has been widely used for variable applications. 42 Unlike traditional 2D materials, it is previously quite a challenge to prepare freestanding 2D GaN by routine exfoliation technologies, because its bulk phase natural...

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Triply degenerate band crossing can generate novel triply degenerate nodal point (TDNP) fermions. For the TDNP character to the best manifest in physical properties, it desires that the TDNPs are near the Fermi level, far away with each other in the reciprocal space, and not coexisting with other quasiparticles or extraneous bands. Here we predict that the centrosymmetic material Li 2 NaN is a realistic TDNP semimetal that meets all these requirements. Li 2 NaN features only a single pair of TDNPs at the Fermi level, under the protection of the C 6v symmetry. Interestingly, the TDNPs identified here show the critical-type band crossing, which is different from those in previously reported TDNP semimetals. The Fermi arc surface states for the TDNPs have been identified. Under lattice strain, we show that the position of the TDNPs can be tuned, and the TDNPs can even be annihilated. The centrosymmetry in Li 2 NaN makes the TDNP transform into a critical type Dirac point under the spin-orbit coupling, which is drastically distinct from those in noncentrosymmetric systems. Such centrosymmetic TDNP semimetal has been rarely identified in realistic materials.Materials with nontrivial band topology have attracted great interests in recent years. Beside their potential technological applications, topological materials provide the possibility to study the fundamental physics theories in the relatively convenient condensed matter scale. For example, Weyl (Dirac) semimetals 1-14 host Weyl (Dirac) points with doubly (fourfold-) degenerate linear band crossings near the Fermi level, and their low-energy excitations can serve as the analogues of Weyl (Dirac) electrons in high-energy theories. More interestingly, three types of quasiparticle excitations, namely triply, six, and eightfold-degenerate nodal points, which even do not have high-energy counterparts, have also been proposed in realistic topological materials 15,16 . In particular, the triply degenerate nodal points (TDNPs) 17-26 , which are formed by the crossing between a non-degenerate band and a doubly-degenerate band, are proposed to host intriguing physics, such as large negative magnetoresistance 27 , helical anomaly 20 , exotic Fermi surface transitions 19,20 , and unconventional quantum Hall effects 28 .Initially, TDNP semimetals are predicted in some inversion-asymmetric materials, including the strained-HgTe 17 , WC-type materials 19-22 , Heusler compounds 24,25 , NaCu 3 Te 2 family 26 , PtBi 2 compound 29 , etc. Recently, Zhang et al. 23 first reported the existence of TDNPs in the centrosymmetric TiB 2 materials by theoretical prediction. They found the TDNPs in these centrosymmetric materials can transform into a novel type of Dirac points, which are drastically different from those in inversion-asymmetric systems. Beside theoretical predictions, several angle-resolved photoemission spectroscopy (ARPES) and transport experiments have also been carried out to probe the electronic structures around TDNPs in WC-type materials 27,30-33 and the a) Electronic t...

In recent years, realizing new topological phase of matter has been a hot topic in the fields of physics and materials science. Topological semimetals and metals can conventionally be classified into two types: type-I and type-II according to the tilting degree of the fermion cone. Here, it is the first time to report a new topological metal phase with the critical-type nodal line between type-I and type-II nodal line. The critical-type nodal line shows a unique nontrivial band crossing which is composed of a flat band and a dispersive band and leads to a new fermionic state. We propose intermetallic CaPd can be an existing topological metal for the new fermionic state, characterized with critical-type nodal line in the bulk and drumhead band structure on the surface. Our work not only promotes the concept of critical-type nodal line, but also provides the material realization to study its exotic properties in future experiments. arXiv:1812.10627v1 [cond-mat.mes-hall]

The chain-type nodal loops in the reciprocal space can generate exotic nodal chain fermions. Here, we report that LiXY (X = Ca, Ba; Y = Si, Ge) compounds are ideal inner nodal chain semimetals. Their band structures are composed of two connecting nodal loops with either hybrid or type-I band dispersion. The signatures of the nodal chain, such as the nontrivial surface states, are quite pronounced in these LiXY compounds, since there is only a single inner nodal chain without other extraneous bands near the Fermi level. These compounds are existing materials and ambient-stable, which is available to realize the experimental detection of inner nodal chain fermions or further the practical applications.

Since the discovery of penta-graphene, two-dimensional (2-D) pentagonal-structured materials have been highly expected for desirable performance because of their unique structures and accompanied physical properties. Hence, based on the first-principles...