Kovalenko's Full-Rank Limit and Overhead as Lower Bounds for Error-Performances of LDPC and LT Codes over Binary Erasure Channels

We present Kovalenko's full-rank limit as a tight lower bound for decoding error probability of LDPC codes and LT codes over BEC. From the limit, we derive a full-rank overhead as a lower bound for stable overheads for successful maximum-likelihood decoding of the codes.Comment: A short version of this paper was presented at ISITA 2008, Auckland NZ. The first draft was submitted to IEEE Transactions on Information Theory, 2008/0

Understanding public support for carbon capture and storage policy: The roles of social capital, stakeholder perceptions, and perceived risk/ benefit of technology

Bureau of Economic Geolog

Ferromagnetism in Mn-doped Chalcopyrite AlGaP2 Semiconductor

The electronic property and the magnetism of AlGaMnP2 compound by 3.125 %, 6.25 %, and 9.375 % Mn concentrations were investigated using the first-principles calculations. The Mn-doped AlGaP2 chalcopyrite with or without defect of Al, Ga, or P atom yields a strong half-metallic ground state. The ferromagnetic state is the most energetically favorable one. The spin-polarization of Mn dopant is stable with a magnetic moment close to 4μB due to intra-atomic exchange coupling. The states of host Al, Ga, or P atoms at the Fermi level are mainly a P-3p character, which mediates a strong interaction between the Mn-3d and P-3p states. The ferromagnetic state with high magnetic moment is originated from the hybridized P(3p)-Mn(3d)-P(3p) interaction formed through the p-d coupling without the defects. It is noted that the ferromagnetism arises from two distinguishing characteristics by polarons and by holes-mediated exchange-coupling

The investigation of ship maneuvering with hydrodynamic effects between ships in curved narrow channel

AbstractThe hydrodynamic interaction between two large vessels can't be neglected when two large vessels are closed to each other in restricted waterways such as in a harbor or narrow channel. This paper is mainly concerned with the ship maneuvering motion based on the hydrodynamic interaction effects between two large vessels moving each other in curved narrow channel. In this research, the characteristic features of the hydrodynamic interaction forces between two large vessels are described and illustrated, and the effects of velocity ratio and the spacing between two vessels are summarized and discussed. Also, the Inchon outer harbor area through the PALMI island channel in Korea was selected, and the ship maneuvering simulation was carried out to propose an appropriate safe speed and distance between two ships, which is required to avoid sea accident in confined waters. From the inspection of this investigation, it indicates the following result. Under the condition of SP12≤0.5L, it may encounter a dangerous tendency of grounding or collision due to the combined effect of the interaction between ships and external forces. Also considering the interaction and wind effect as a parameter, an overtaken and overtaking vessel in narrow channel can navigate while keeping its own original course under the following conditions; the lateral separation between two ships is about kept at 0.6 times of ship length and 15 degrees of range in maximum rudder angle. On the other hand, two ships while overtaking in curved narrow channel such as Inchon outer harbor in Korea should be navigated under the following conditions; SP12 is about kept at 1.0 times of ship length and the wind velocity should not be stronger than 10 m/s

Bis[μ-N-(pyridin-2-ylmeth­yl)pyridin-2-amine-κ2 N:N′]disilver(I) bis(trifluoro­methane­sulfonate)

In the binuclear title compound, [Ag2(C11H11N3)2](CF3O3S)2, the complex cation is centrosymmetric, with the unique Ag+ cation coordinated by two pyridine N atoms from two symmetry-related N-(pyridin-2-ylmeth­yl)pyridin-2-amine ligands in a geometry slightly distorted from linear [N—Ag—N 161.02 (7)°]. This set-up leads to the formation of a 14-membered cyclic dimer. The two pyridine rings coordinated to the Ag+ cation are tilted by 80.19 (7)° with respect to each other. Inter­molecular N—H⋯O hydrogen-bonding inter­actions between the cyclic dimer and the anion exist. A two-dimensional network parallel to the ac plane is constructed by three weak Ag⋯(O,N) inter­actions as well as an F⋯F contact of 2.890 (4) Å

Extract of Allium tuberosum Rottler ex Spreng

Allium tuberosum Rottler ex Spreng (ATRES) has been used as a traditional medicine for the treatment of abdominal pain, diarrhea, and asthma. In this study, we investigated the hair growth promoting activities of ATRES on telogenic C57BL6/N mice. Hair growth was significantly increased in the dorsal skin of ethanol extract of ATRES treated mouse group compared with the control mouse group. To enrich the hair promoting activity, an ethanol-insoluble fraction was further extracted in sequence with n-hexane, dichloromethane, ethyl acetate, n-butanol, and distilled water. Interestingly, we found that extraction with n-butanol is most efficient in producing the hair promoting activity. In addition, the soluble fraction of the n-butanol extract was further separated by silica gel chromatography and thin layer chromatography (TLC) resulting in isolating four single fractions which have hair growth regeneration potential. Furthermore, administration of ATRES extracts to dorsal skin area increased the number of hair follicles compared with control mouse group. Interestingly, administration of ATRES extract stimulated the expression of insulin-like growth factor-1 (IGF-1) but not of keratin growth factor (KGF) or vascular endothelial growth factor (VEGF). Taken together, these results suggest that ATRES possesses strong hair growth promoting potential which controls the expression of IGF-1

The voltage-gated potassium channel Shaker promotes sleep via thermosensitive GABA transmission

Genes and neural circuits coordinately regulate animal sleep. However, it remains elusive how these endogenous factors shape sleep upon environmental changes. Here, we demonstrate that Shaker (Sh)-expressing GABAergic neurons projecting onto dorsal fan-shaped body (dFSB) regulate temperature-adaptive sleep behaviors in Drosophila. Loss of Sh function suppressed sleep at low temperature whereas light and high temperature cooperatively gated Sh effects on sleep. Sh depletion in GABAergic neurons partially phenocopied Sh mutants. Furthermore, the ionotropic GABA receptor, Resistant to dieldrin (Rdl), in dFSB neurons acted downstream of Sh and antagonized its sleep-promoting effects. In fact, Rdl inhibited the intracellular cAMP signaling of constitutively active dopaminergic synapses onto dFSB at low temperature. High temperature silenced GABAergic synapses onto dFSB, thereby potentiating the wake-promoting dopamine transmission. We propose that temperature-dependent switching between these two synaptic transmission modalities may adaptively tune the neural property of dFSB neurons to temperature shifts and reorganize sleep architecture for animal fitness. Ji-hyung Kim and Yoonhee Ki et al. show that low temperatures suppress sleep in Drosophila by increasing GABA transmission in Shaker-expressing GABAergic neurons projecting onto the dorsal fan-shaped body, while high temperatures potentiate dopamine-induced arousal by reducing GABA transmission. This study highlights a role for Shaker in sleep modulation via a temperature-dependent switch in GABA signaling

N-(Pyridin-2-ylmeth­yl)pyridin-2-amine

The title compound, C11H11N3, crystallizes with two mol­ecules (A and B) in the asymmetric unit. The geometries of both mol­ecules are very similar, with the exception of the torsion angles of the inter-ring chains; the values for C—N—C—C are 67.4 (5) and −69.3 (5)° for mol­ecules A and B, respectively. The dihedral angles between the pyridyl ring planes are 84.0 (2) and 83.2 (2)° for mol­ecules A and B, respectively. In the crystal, weak inter­molecular N—H⋯N hydrogen bonds and C—H⋯π inter­actions contribute to the stabilization of the packing