Luttinger Parameter g for Metallic Carbon Nanotubes and Related Systems

The random phase approximation (RPA) theory is used to derive the Luttinger parameter g for metallic carbon nanotubes. The results are consistent with the Tomonaga-Luttinger models. All metallic carbon nanotubes, regardless if they are armchair tubes, zigzag tubes, or chiral tubes, should have the same Luttinger parameter g. However, a (10,10) carbon peapod should have a smaller g value than a (10,10) carbon nanotube. Changing the Fermi level by applying a gate voltage has only a second order effect on the g value. RPA theory is a valid approach to calculate plasmon energy in carbon nanotube systems, regardless if the ground state is a Luttinger liquid or Fermi liquid. (This paper was published in PRB 66, 193405 (2002). However, Eqs. (6), (9), and (19) were misprinted there.)Comment: 2 figure

Molecular cloning and characterization of a cytoplasmic cyclophilin gene in sugarcane

Cyclophilins are ubiquitous proteins with an enzymatic activity of peptidyl-prolyl cis-trans isomerase (PPIase), which play important roles in a variety of stress responsiveness. In this study, we reported the cloning and characterization of a full-length cytoplasmic cyclophilin gene in sugarcane. Sequence analysis showed the cDNA of this gene (GenBank accession number:GQ246462), termed as Sc-CyP, was 904 bp long, including a 519 bp complete ORF, the 5’ UTR of 74 bp and 3’UTR of 311 bp, plus a typical AATAA motif and poly (A) tail. It encoded the 172 amino acid polypeptide with a molecular weight of 18.4 KD and the isoelectric point of 8.68. The Sc-CyP encoding protein had the conserved site Trp128 (W128) ubiquitious of all cyclophilins in eukaryotes and the KSGKPLH48-54 region specific to cytoplasmic cyclophilins in plants. SDS-PAGE analysis and PPIase assay revealed that the expression product, with PPIase activity, was a fusion protein with a molecular weight about 25 and 18.4 kD of Sc- CyP plus 7 kD of His • Tag peptides. In real-time qPCR analysis, the Sc-CyP gene showed induced expression under PEG, NaCl, SA and H2O2 stresses, indicating it a stress-related gene for drought and salt stress, signal transduction and disease resistance response in sugarcane.Key words: Sugarcane (Saccharum officinarum), cyclophilin, PPIase, real-time quantitative PCR

Molecular cloning and expression analysis of a zeta-class glutathione S-transferase gene in sugarcane

Glutathione S-transferases (GSTs) play an important role in stress tolerance in plants. This is the first report of cloning and characterization of a zeta-class GST gene in sugarcane (GenBank Accession number: GQ246461). Sequence analysis showed that the cDNA sequence of Sc-GST gene was 829 bp, contained a 621 bp open reading frame (ORF), the 5’ untranslated region (UTR) of 65 bp and 3’UTR of 143 bp, plus the typical AATAA region and poly (A) tail. It encoded the 206 amino acid residues with a molecular mass of 23.1 KD and isoelectric point of 6.10. Protein domain prediction and multiple sequence alignment demonstrated that the conserved domain in Sc-GST at N-terminus was SSCXXRXRIA, while that at C-terminus was quebec platelet disorder (QPD), both of which were specific for zeta-type GST in eukaryotes. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis and enzyme activity assay indicated that the prokaryotic expression product was a fusion protein with a molecular weight of about 30 KD, which also possessed GST enzyme activity. It was revealed in real-time quantitative polymerase chain reaction (qPCR) analysis that the Sc-GST gene had induced expression under H2O2 and Ustilago scitaminea stresses, while it was inhibited and then induced by salicylic acid (SA) stress, suggesting that it is a type of stress-tolerant gene playing a certain role in sugarcane resistance response.Key words: Saccharum officinarum, glutathione S-transferase, homology, prokaryotic expression, real-time quantitative PCR

Efek Durasi Penggunaan Masker Kain Terhadap End-tidal Karbon Dioksida Pada Mahasiswa Fakultas Kedokteran Universitas Pattimura

Abstrak Masker kain berfungsi untuk melindungi pengguna dari partikel yang terbawa melalui droplet, atau airborne. Penggunaan masker kain dengan jangka waktu yang lebih lama dapat menimbulkan hiperkapnia dengan gejala berupa dyspnea, takikardia, pusing, dan nyeri kepala, yang ditandai dengan kadar CO2 >45. Metode penelitian ini yaitu metode eksperimental, dengan teknik pengambilan simple random sampling, dengan jumlah responden 36 yang dibagi dalam dua kelompok yaitu kontrol dan perlakuan. Data hasil pengamatan dianalisis menggunakan uji Independent Sample T-Test apabila data berdistribusi normal dan mann-whitney jika berdistribusi tidak normal. Hasil uji Mann-Whitney menunjukkan bahwa pada menit ke-0 nilai p = 0, 864, hasil uji Independent Sample T-Test pada menit ke-30 kelompok kontrol nilai p = 0, 850, kelompok perlakuan nilai p = 0, 851 menit ke-60 kelompok kontrol nilai p = 0,935, perlakuan nilai p = 0,935, menit ke-90 kelompok kontrol nilai p = 0,568, kelompok perlakuan nilai p = 0,569 menit ke-120 kelompok kontrol nilai p = 0,056, kelompok perlakuan nilai p = 0,056. Dari hasil kelima pengukuran tersebut rata-rata nilai p = >0,05 yang artinya tidak ada perbedaan yang signifikan. Kesimpulan dari penelitian ini menunjukan bahwa tidak ada efek dari durasi penggunaan masker kain terhadap end-tidal karbon dioksida dalam waktu 2 jam pada mahasiswa Fakultas Kedokteran Universitas Pattimura,dan tidak menunjukan tanda dan gejala yang muncul sebagai efek durasi penggunaan masker kain dalam waktu 2 jam, dengan lima kali pengukuran, yaitu pada menit ke-0, 30, 60, 90 dan 120. Abstract Cloth masks serve to protect users from particles carried through droplets, or airborne. The use of cloth masks for a longer period of time can cause hypercapnia with symptoms such as dyspnea, tachycardia, dizziness, and headaches, which are characterized by CO2 levels >45. This research method is an experimental method, with a simple random sampling technique, with 36 respondents divided into two groups, namely control and treatment. Observational data were analyzed using the Independent Sample T-Test if the data was normally distributed and Mann-Whitney if the distribution was not normal. The results of the Mann-Whitney test showed that at minute 0 the p value = 0.864, the results of the Independent Sample T-Test test at minute 30 the control group p value = 0.850, the treatment group p value = 0.851 minutes to -60 control group p value = 0,935, treatment p value = 0,935, 90th minute control group p value = 0,568, treatment group p value = 0,569 minute 120 control group p value = 0,056, treatment group p value = 0,056. From the results of the five measurements, the average p value = > 0.05, which means there is no significant difference. The test results mean that there is no effect between the duration of using a cloth mask on the end-tidal carbon dioxide

Far-infrared absorption in parallel quantum wires with weak tunneling

We study collective and single-particle intersubband excitations in a system of quantum wires coupled via weak tunneling. For an isolated wire with parabolic confinement, the Kohn's theorem guarantees that the absorption spectrum represents a single sharp peak centered at the frequency given by the bare confining potential. We show that the effect of weak tunneling between two parabolic quantum wires is twofold: (i) additional peaks corresponding to single-particle excitations appear in the absorption spectrum, and (ii) the main absorption peak acquires a depolarization shift. We also show that the interplay between tunneling and weak perpendicular magnetic field drastically enhances the dispersion of single-particle excitations. The latter leads to a strong damping of the intersubband plasmon for magnetic fields exceeding a critical value.Comment: 18 pages + 6 postcript figure

RESPON IMUN SELULER DAN HUMORAL TERHADAP INFEKSI HIV

Pendahuluan. Sistem imun terbagi menjadi dua cabang, imunitas humoral, yang merupakan fungsi protektif ditemukan pada humor dan imunitas selular, yang fungsi protektifnya berkaitan dengan sel. Orang yang terinfeksi HIV (Human Immunodeficiency Virus) membentuk respons humoral dan selular. Respons imun awal terhadap infeksi HIV mempunyai karakteristik ekspansi masif sel T sitotoksik CD8+ yang spesifik terhadap protein HIV menyebabkan terganggunya sistem alamiah dan didapat dimana yang menjadi target spesifik infeksi adalah limfosit CD4+, menyebabkan lisis sel T CD4+. Penyebab terpenting kurangnya sel T CD4+ pada orang terinfeksi HIV adalah efek sitopatik langsung. Respon imun selular dan humoral sama penting dalam pembentukan kekebalan terhadap infeksi virus, dimana tujuan utama respon imun terhadap infeksi virus HIV ialah eliminasi terhadap virus yang menginfeksi sel dan sel-sel yang mengandung virus atau tempat replikasi virus

Genome-wide functional analysis reveals that autophagy is necessary for growth, sporulation, deoxynivalenol production and virulence in Fusarium graminearum

Autophagy is a conserved cellular recycling and trafficking pathway in eukaryotic cells and has been reported to be important in the virulence of a number of microbial pathogens. Here, we report genome-wide identification and characterization of autophagy-related genes (ATGs) in the wheat pathogenic fungus Fusarium graminearum. We identified twenty-eight genes associated with the regulation and operation of autophagy in F. graminearum. Using targeted gene deletion, we generated a set of 28 isogenic mutants. Autophagy mutants were classified into two groups by differences in their growth patterns. Radial growth of 18 Group 1 ATG mutants was significantly reduced compared to the wild-type strain PH-1, while 10 Group 2 mutants grew normally. Loss of any of the ATG genes, except FgATG17, prevented the fungus from causing Fusarium head blight disease. Moreover, subsets of autophagy genes were necessary for asexual/sexual differentiation and deoxynivalenol (DON) production, respectively. FgATG1 and FgATG5 were investigated in detail and showed severe defects in autophagy. Taken together, we conclude that autophagy plays a critical role in growth, asexual/sexual sporulation, deoxynivalenol production and virulence in F. graminearum

Lamellar to Rod Eutectic Transition in the Hypereutectic Nickel- Aluminum Alloy

Directional solidification experiments were carried out on the hypereutectic Ni-25 at.% Al alloy to examine the effect of growth velocity on the eutectic microstructure. The growth velocity was varied from 1 to 20 μm/s at a constant temperature gradient of 10.0 K/mm. The microstructural observations of unidirectionally solidified samples show that the lamellar eutectic growth was observed in the sample solidified at a constant velocity of 1 μm/s and the rod eutectic growth at velocities higher than 10 μm/s. A microstructural transition from lamellar to rod eutectics was achieved at the intermediate velocity. The lamellar to rod eutectic transition was shown to result from the compositional change due to the presence of strong convection in the melt. The undercooling-spacing curves showed that the average eutectic spacings for the lamellar and the rod structures were 1.6 times larger than that in the minimum undercooling for a given velocity