Temperature-driven transition from the Wigner Crystal to the Bond-Charge-Density Wave in the Quasi-One-Dimensional Quarter-Filled band

It is known that within the interacting electron model Hamiltonian for the one-dimensional 1/4-filled band, the singlet ground state is a Wigner crystal only if the nearest neighbor electron-electron repulsion is larger than a critical value. We show that this critical nearest neighbor Coulomb interaction is different for each spin subspace, with the critical value decreasing with increasing spin. As a consequence, with the lowering of temperature, there can occur a transition from a Wigner crystal charge-ordered state to a spin-Peierls state that is a Bond-Charge-Density Wave with charge occupancies different from the Wigner crystal. This transition is possible because spin excitations from the spin-Peierls state in the 1/4-filled band are necessarily accompanied by changes in site charge densities. We apply our theory to the 1/4-filled band quasi-one-dimensional organic charge-transfer solids in general and to 2:1 tetramethyltetrathiafulvalene (TMTTF) and tetramethyltetraselenafulvalene (TMTSF) cationic salts in particular. We believe that many recent experiments strongly indicate the Wigner crystal to Bond-Charge-Density Wave transition in several members of the TMTTF family. We explain the occurrence of two different antiferromagnetic phases but a single spin-Peierls state in the generic phase diagram for the 2:1 cationic solids. The antiferromagnetic phases can have either the Wigner crystal or the Bond-Charge-Spin-Density Wave charge occupancies. The spin-Peierls state is always a Bond-Charge-Density Wave.Comment: 12 pages, 8 EPS figures. Longer version of previous manuscript. Contains new numerical data as well as greatly expanded discussio

Spin-charge gauge symmetry: A way to tackle HTS cuprates?

We propose an explanation of several experimental features of transport phenomena in the normal state of high Tc cuprates in terms of a spin-charge gauge theory of the 2D t-J model. The calculated doping-temperature dependence for a number of physical quantities is found in qualitative agreement with data. In particular, we recover: in the ``pseudogap phase'' the metal-insulator crossover of the in-plane resistivity and of the NMR ``relaxation time'' and the insulating behavior of the out-of-plane resistivity; in the ``strange metal phase'' (at higher temperature or doping) the linear in T behavior of the above quantities; the appearance of maxima in the in-plane far-infrared conductivity in strongly underdoped and overdoped samples.Comment: 8 pages, 14 figures; to appear without figures in Journal of Physics and Chemistry of Solid

Changes in autofluorescence based organoid model of muscle invasive urinary bladder cancer

Muscle invasive urinary bladder cancer is one of the most lethal cancers and its detection at the time of transurethral resection remains limited and diagnostic methods are urgently needed. We have developed a muscle invasive transitional cell carcinoma (TCC) model of the bladder using porcine bladder scaffold and the human bladder cancer cell line 5637. The progression of implanted cancer cells to muscle invasion can be monitored by measuring changes in the spectrum of endogenous fluorophores such as reduced nicotinamide dinucleotide (NADH) and flavins. We believe this could act as a useful tool for the study of fluorescence dynamics of developing muscle invasive bladder cancer in patients

Identification of tammar wallaby SIRH12, derived from a marsupial-specific retrotransposition event

In humans and mice, there are 11 genes derived from sushi-ichi related retrotransposons, some of which are known to play essential roles in placental development. Interestingly, this family of retrotransposons was thought to exist only in eutherian mammals, indicating their significant contributions to the eutherian evolution, but at least one, PEG10, is conserved between marsupials and eutherians. Here we report a novel sushi-ichi retrotransposon-derived gene, SIRH12, in the tammar wallaby, an Australian marsupial species of the kangaroo family. SIRH12 encodes a protein highly homologous to the sushi-ichi retrotransposon Gag protein in the tammar wallaby, while SIRH12 in the South American short-tailed grey opossum is a pseudogene degenerated by accumulation of multiple nonsense mutations. This suggests that SIRH12 retrotransposition occurred only in the marsupial lineage but acquired and retained some as yet unidentified novel function, at least in the lineage of the tammar wallaby

The Human Nucleolar Protein FTSJ3 Associates with NIP7 and Functions in Pre-rRNA Processing

NIP7 is one of the many trans-acting factors required for eukaryotic ribosome biogenesis, which interacts with nascent pre-ribosomal particles and dissociates as they complete maturation and are exported to the cytoplasm. By using conditional knockdown, we have shown previously that yeast Nip7p is required primarily for 60S subunit synthesis while human NIP7 is involved in the biogenesis of 40S subunit. This raised the possibility that human NIP7 interacts with a different set of proteins as compared to the yeast protein. By using the yeast two-hybrid system we identified FTSJ3, a putative ortholog of yeast Spb1p, as a human NIP7-interacting protein. A functional association between NIP7 and FTSJ3 is further supported by colocalization and coimmunoprecipitation analyses. Conditional knockdown revealed that depletion of FTSJ3 affects cell proliferation and causes pre-rRNA processing defects. The major pre-rRNA processing defect involves accumulation of the 34S pre-rRNA encompassing from site A′ to site 2b. Accumulation of this pre-rRNA indicates that processing of sites A0, 1 and 2 are slower in cells depleted of FTSJ3 and implicates FTSJ3 in the pathway leading to 18S rRNA maturation as observed previously for NIP7. The results presented in this work indicate a close functional interaction between NIP7 and FTSJ3 during pre-rRNA processing and show that FTSJ3 participates in ribosome synthesis in human cells

The NIP7 protein is required for accurate pre-rRNA processing in human cells

Eukaryotic ribosome biogenesis requires the function of a large number of trans-acting factors which interact transiently with the nascent pre-rRNA and dissociate as the ribosomal subunits proceed to maturation and export to the cytoplasm. Loss-of-function mutations in human trans-acting factors or ribosome components may lead to genetic syndromes. In a previous study, we have shown association between the SBDS (Shwachman–Bodian–Diamond syndrome) and NIP7 proteins and that downregulation of SBDS in HEK293 affects gene expression at the transcriptional and translational levels. In this study, we show that downregulation of NIP7 affects pre-rRNA processing, causing an imbalance of the 40S/60S subunit ratio. We also identified defects at the pre-rRNA processing level with a decrease of the 34S pre-rRNA concentration and an increase of the 26S and 21S pre-rRNA concentrations, indicating that processing at site 2 is particularly slower in NIP7-depleted cells and showing that NIP7 is required for maturation of the 18S rRNA. The NIP7 protein is restricted to the nuclear compartment and co-sediments with complexes with molecular masses in the range of 40S–80S, suggesting an association to nucleolar pre-ribosomal particles. Downregulation of NIP7 affects cell proliferation, consistently with an important role for NIP7 in rRNA biosynthesis in human cells

The NIP7 protein is required for accurate pre-rRNA processing in human cells

Eukaryotic ribosome biogenesis requires the function of a large number of trans-acting factors which interact transiently with the nascent pre-rRNA and dissociate as the ribosomal subunits proceed to maturation and export to the cytoplasm. Loss-of-function mutations in human trans-acting factors or ribosome components may lead to genetic syndromes. In a previous study, we have shown association between the SBDS (Shwachman–Bodian–Diamond syndrome) and NIP7 proteins and that downregulation of SBDS in HEK293 affects gene expression at the transcriptional and translational levels. In this study, we show that downregulation of NIP7 affects pre-rRNA processing, causing an imbalance of the 40S/60S subunit ratio. We also identified defects at the pre-rRNA processing level with a decrease of the 34S pre-rRNA concentration and an increase of the 26S and 21S pre-rRNA concentrations, indicating that processing at site 2 is particularly slower in NIP7-depleted cells and showing that NIP7 is required for maturation of the 18S rRNA. The NIP7 protein is restricted to the nuclear compartment and co-sediments with complexes with molecular masses in the range of 40S–80S, suggesting an association to nucleolar pre-ribosomal particles. Downregulation of NIP7 affects cell proliferation, consistently with an important role for NIP7 in rRNA biosynthesis in human cells

アートプロジェクトによる地域・建築リノベーションの継続的発展性/「沙弥島アートプロジェクト by神戸芸術工科大学」の実践を通して

近年、アートプロジェクトを媒介とした地域活性化が盛んである。本学でも2013年3月から開催された「瀬戸内国際芸術祭2013」以来、「沙弥島アートプロジェクト」として香川県坂出市を対象地として活動してきている。これまでの活動については本学紀要「芸術工学 2013」「芸術工学 2014」においても報告してきているので、本稿は2014年度の活動について報告するものである。2014年度は主として2つのプロジェクトを実施した。今年度は、芸術祭自体の開催年ではないので、芸術性の高い作家の作品を展示するのではなく、市民参加型の創作として、アートに関心を持ってもらうことを主眼にしている。「アートのちからで壁画創生プロジェクト2014」では、坂出市民美術館敷地内の庭園の塀にワークショップ形式で壁画を創作した。「ART SETOUCHI 2014 沙弥島アートプロジェクト」は瀬戸内国際芸術祭の一環に位置付けられるものであるが、芸術祭主会場である旧沙弥小中学校を会場に、市民が栽培したコスモスの鉢植えをモチーフとしたインスタレーションを制作した。　これまでのプロジェクトの参加者は、どうしても児童や高年齢者などの時間に余裕のある人が中心だったが、今回は仕事をしている層を取り込むことが出来たことに意義を感じている。Since the participation to the Setouchi Triennale 2013, we continue the art project activities ‘Shamijima Art Project by Kobe Design University’ . Achievements of these project were reported on bulletin of ‘2012’ and ‘2013’. 　In 2014, we planned a couple of work shop projects and consider the way of continuous community design by arts and architectural works.‘SAKAIDE no　Shio’　the tide of SAKAIDE.Wall painting project at Sakaide citizen museum. Old concrete block fence of museum garden was recoating by blue motif graphic. These motifs were abstracted from sea side scape of Sakaide. ‘ART SETOCHI 2014’ Installation art works.‘Cosmos project’ and ‘Together man project’. Innumerable potted cosmos flowers were grown by Sakaide community residents and installed in the former Shami elementary school’s classroom. Collaborators also create ‘together man’ figure and note a message on together man’s body

Ground state and finite temperature behavior of 1/4-filled band zigzag ladders

We consider the simplest example of lattice frustration in the 1/4-filled band, a one-dimensional chain with next-nearest neighbor interactions. For this zigzag ladder with electron-electron as well as electron-phonon interactions we present numerical results for ground state as well as thermodynamic properties. In this system the ground state bond distortion pattern is independent of electron-electron interaction strength. The spin gap in the ground state of the zigzag ladder increases with the degree of frustration. Unlike in one-dimension, where the spin-gap and charge ordering transitions can be distinct, we show that in the ladder they occur simultaneously. We discuss spin gap and charge ordering transitions in 1/4-filled materials with one, two, or three dimensional crystal structures. We show empirically that regardless of dimensionality the occurrence of simultaneous or distinct charge and magnetic transitions can be correlated with the ground state bond distortion pattern.Comment: 12 pages, 8 eps figure

Insights into Land Plant Evolution Garnered from the Marchantia polymorpha Genome.

The evolution of land flora transformed the terrestrial environment. Land plants evolved from an ancestral charophycean alga from which they inherited developmental, biochemical, and cell biological attributes. Additional biochemical and physiological adaptations to land, and a life cycle with an alternation between multicellular haploid and diploid generations that facilitated efficient dispersal of desiccation tolerant spores, evolved in the ancestral land plant. We analyzed the genome of the liverwort Marchantia polymorpha, a member of a basal land plant lineage. Relative to charophycean algae, land plant genomes are characterized by genes encoding novel biochemical pathways, new phytohormone signaling pathways (notably auxin), expanded repertoires of signaling pathways, and increased diversity in some transcription factor families. Compared with other sequenced land plants, M. polymorpha exhibits low genetic redundancy in most regulatory pathways, with this portion of its genome resembling that predicted for the ancestral land plant. PAPERCLIP