4,884 research outputs found
Mutual correlation in the shock wave geometry
We probe the shock wave geometry with the mutual correlation in a spherically
symmetric Reissner Nordstr\"om AdS black hole on the basis of the gauge/gravity
duality. In the static background, we find that the regions living on the
boundary of the AdS black holes are correlated provided the considered regions
on the boundary are large enough. We also investigate the effect of the charge
on the mutual correlation and find that the bigger the value of the charge is,
the smaller the value of the mutual correlation will to be. As a small
perturbation is added at the AdS boundary, the horizon shifts and a dynamical
shock wave geometry forms after long time enough. In this dynamic background,
we find that the greater the shift of the horizon is, the smaller the mutual
correlation will to be. Especially for the case that the shift is large enough,
the mutual correlation vanishes, which implies that the considered regions on
the boundary are uncorrelated. The effect of the charge on the mutual
correlation in this dynamic background is found to be the same as that in the
static background.Comment: 10 page
Performance and energy efficiency analysis of data center cooling plant by using lake water source
A cooling plant by using lake water source was proposed to cool the space in data centers. It combines free cooling technology and variable capacity technology to remove heat and reduce energy consumption effectively. In this paper, firstly, the control strategies for this cooling plant were proposed. Then, a detailed annual energy consumption model with considering the effect of the dynamic heat dissipation characteristics of servers, lake water temperature, outdoor weather conditions, and cooling plant thermal performance, will be established to evaluate the performance and energy efficiency of this cooling plant under different load factors. The results show the mode 1 and mode 2 of this cooling plant are 67.6% and 32.4% of the year’s running time, respectively. The average EER of the cooling plant under different load factor ranges from 16.8~49.3, and the average PUE value ranges from 1.11 to 1.15 under different load factors, which demonstrates this cooling plant poses higher energy efficiency than the conventional cooling plant for the data centers
Formation of Nanofoam carbon and re-emergence of Superconductivity in compressed CaC6
Pressure can tune material's electronic properties and control its quantum
state, making some systems present disconnected superconducting region as
observed in iron chalcogenides and heavy fermion CeCu2Si2. For CaC6
superconductor (Tc of 11.5 K), applying pressure first Tc increases and then
suppresses and the superconductivity of this compound is eventually disappeared
at about 18 GPa. Here, we report a theoretical finding of the re-emergence of
superconductivity in heavily compressed CaC6. The predicted phase III (space
group Pmmn) with formation of carbon nanofoam is found to be stable at wide
pressure range with a Tc up to 14.7 K at 78 GPa. Diamond-like carbon structure
is adhered to the phase IV (Cmcm) for compressed CaC6 after 126 GPa, which has
bad metallic behavior, indicating again departure from superconductivity.
Re-emerged superconductivity in compressed CaC6 paves a new way to design
new-type superconductor by inserting metal into nanoporous host lattice.Comment: 31 pages, 12 figures, and 4 table
Ethyl 6-(4-fluorophenyl)-4-hydroxy-2-oxo-4-trifluoromethyl-1,3-diazinane-5-carboxylate monohydrate
The asymmetric unit of the title compound, C14H14F4N2O4·H2O, contains two crystallographically independent organic molecules and two water molecules. The two 1,3-diazinane rings adopt a half-chair conformation and the dihedral angles between their mean planes and those of the benzene rings are 75.65 (4)° and 49.41 (3)° in the two molecules. The crystal structure is stabilized by intermolecular O—H⋯O and N—H⋯O hydrogen bonds
The sensitivity and specificity of one field non-mydriatic digital fundus photography for DR screening
AIM:To evaluate the sensitivity and specificity of one-field non-mydriatic digital fundus photography and direct ophthalmoscopy for diabetic retinopathy(DR)screening, compared with fundus fluorescein angiography( FFA ).<p>METHODS:All 93 patients of type 1 or 2 diabetic who have underwent one-field non-mydriatic digital fundus photography, and direct ophthalmoscopy with dilation of their pupils, and FFA by ophthalmologists. The sensitivity and specificity of one-field non-mydriatic digital fundus photography and direct ophthalmoscopy were calculated respectively, compared with FFA.<p>RESULTS: The sensitivity and specificity of one-field non-mydriatic digital fundus photography for detection of any DR were 80.4% and 94.7%; The sensitivity and specificity of direct ophthalmoscopy for detection of any DR were 64.2% and 84.2%; After the standard for referable DR being lowered down to the moderate non-proliferative diabetic retinopathy(M-NPDR), the sensitivity and specificity of non-mydriatic digital fundus photography for detection were 88.9% and 98.4%, the sensitivity and specificity of direct ophthalmoscopy for detection were 71.5% and 96.7%.<p>CONCLUSION: One-field non-mydriatic digital fundus photography is an effective method for DR screening
ENAT-PT: An Enhanced NAT-PT Model
NAT-PT would allow IPv4 nodes to communicate with IPv6 nodes transparently by translating the IPv6 address into a registered V4 address. However, NAT-PT would fall flat when the pool of V4 addresses is exhausted. NAPT-PT multiplexes the registered address’ ports and will allow for a maximum of 63K outbound TCP and 63K UDP sessions per IPv4 address, but it is unidirectional. We present in this paper a novel solution ENAT-PT(an enhanced NAT-PT),which will allow for a great number of inbound sessions by using a single V4 address. By using ENAT-PT, we can visit V6 networks from a V4 network with a small address pool
Two NHX-type transporters from Helianthus tuberosus improve the tolerance of rice to salinity and nutrient deficiency stress.
The NHX-type cation/H+ transporters in plants have been shown to mediate Na+ (K+ )/H+ exchange for salinity tolerance and K+ homoeostasis. In this study, we identified and characterized two NHX homologues, HtNHX1 and HtNHX2 from an infertile and salinity tolerant species Helianthus tuberosus (cv. Nanyu No. 1). HtNHX1 and HtNHX2 share identical 5'- and 3'-UTR and coding regions, except for a 342-bp segment encoding 114 amino acids (L272 to Q385 ) which is absent in HtNHX2. Both hydroponics and soil culture experiments showed that the expression of HtNHX1 or HtNHX2 improved the rice tolerance to salinity. Expression of HtNHX2, but not HtNHX1, increased rice grain yield, harvest index, total nutrient uptake under K+ -limited salt-stress or general nutrient deficiency conditions. The results provide a novel insight into NHX function in plant mineral nutrition
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