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Base on January and July 4-times daily ECMWF Interim data from 2009 to 2018 over the Northeast Sphere (0–180E,0–90N), the condensed moisture profile of experiential methods and that of ECMWF analysis are compared. The result shows that, the meridional-height distribution of mean cloud condensed moisture has a maximum slab spreading near ground in the Arctic region in July, and the maximum takes a circular shape at 700 hPa above 30N latitude in January. The distribution feature unlike the universal profile, it distributes in a single or double peak function manner, instead of a constant value. The quick decreasing level height and thickness varies with latitude, especially in January. The second experiential profile concerning warm cloud assumes air parcel lifting adiabatically, the liquid water path (LWP) is compared for general information. The result shows that the experiential LWP is much larger than that of the reanalysis by 1 to 2 order, decreasing with latitudes. The possible reason of LWP difference is from the critic water content value of cloud boundary identification. If the value is small, the thickness of warm cloud will be large, temperature and pressure at the cloud base are both large too, results in a larger LWP. These results will enrich the knowledge of the condensed moisture characteristics of ECMWF reanalysis and the experiential moisture profile methods.

Nitrogen (N) is an essential macronutrient for crop growth and yield, but excessive application of N fertilizer has caused serious environmental pollution and greatly increased the cost of agricultural production. One of the effective and economical solutions to this dilemma is to improve the N use efficiency (NUE) of crops. Although some components involved in regulating NUE have been identified, the underlying molecular mechanism remains largely elusive in rice. Here we report that the OsNLP3 (NIN-like protein 3) is an important regulator in NUE and grain yield under nitrate-sufficient conditions. Both NUE and grain yield were significantly improved by enhanced OsNLP3 expression in the field, but reduced in osnlp3 mutants. The expression of OsNLP3 responds to both nitrate and ammonium, while OsNLP3 nuclear retention is only induced by nitrate, not by ammonium. OsNLP3 regulates the expression of a set of genes involved in N transport and assimilation by directly binding to the nitrate-responsive cis-element in the promoters of these genes. Our study demonstrates that OsNLP3 is significant for the regulation of NUE and grain yield, particularly in nitrate-rich conditions, thus providing a candidate for improving NUE and grain yield in rice.

To study the expression of linc00601 in hepatocellular carcinoma (HCC) tissues and cells, and to study the biological function and downstream mechanism of linc00601 in HCC using in vitro experiments.The expression of linc00601 in HCC was predicted via bioinformatics, and the expression of linc00601 in HCC tissues and cells was detected via quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR). After interference with the expression of linc00601, the interference efficiency was determined using qRT-PCR, and the changes in HCC cell proliferation, cycle distribution, and apoptosis were determined through Cell Counting Kit-8 (CCK-8) assay and flow cytometry, respectively. Finally, the expressions of molecular markers in downstream signaling pathway were determined through Western blotting.It was found via bioinformatics that the expression of linc00601 was upregulated in HCC. The results of qRT-PCR revealed that the expression of linc00601 was upregulated in 36 cases of HCC tissues compared with that in para-carcinoma tissues, and it was also upregulated in HCC cells. According to the results of CCK-8 assay, HCC cell proliferation was inhibited after interference with the expression of linc00601. In the si-linc00601 group, the apoptosis rate rose, and the cell cycle was arrested at the G1/G0 phase compared with those in the si-NC group. The results of Western blotting revealed that after the knockdown of linc00601 in HCC cells, the expressions of molecular markers (p-P38, p-ERK) in the downstream mitogen-activated protein kinase (MAPK) signaling pathway were downregulated.Linc00601 is upregulated in HCC, which promotes the development of HCC via activating the MAPK signaling pathway.

Equal channel angular extrusion (ECAE) is a promising technique for producing ultra-fine grained (UFG) or nanostructured materials based on the principle of simple shearing. Through analysis, it is shown that only the geometrical factor Φ, namely, the half-angle of the two intersecting channels, and the number of ECAE passes, N, affect the effective strain. The equivalent linear reduction ratio, r0/r1, is derived to describe the size reduction effect of an object such as a grain. The most effective intersecting angle (2Φ) is 90°. Compared to traditional area reduction extrusion, the deformation effect is equivalent to an area reduction ratio of 1 million or a linear reduction ratio of 1022 after 12 passes of ECAE. Magnesium AZ31B, aluminium 6061 and commercially-pure Titanium were used for the study. Three types of die designs for ECAE of each alloy were proposed and numerically analysed. The effective strain, von Mises stress, equivalent area reduction ratio and equivalent linear reduction ratio were compared for the three types of die designs based on the simulation results using ANSYS/LS-DYNA. The parameter Nμ→nm, namely, the number of passes of ECAE required to reduce 100μ structures into 100nm structures, was calculated for each design. A grain size of 100μ can be deformed into a nanostructure through as few as 12-17 passes of ECAE.

Abstract The study examined effect of die casting process parameters on porosity in magnesium alloy AM60B. Porosity is unavoidable in die casting products, but it can be reduced by controlling the process parameters. It is shown in this work that die casting parameters such as plunger stroke, first phase speed, second phase speed and consolidation pressure all have a significant influence on the porosity level of AM60B magnesium die castings. The relationship between the porosity level and the processing parameters has been investigated. The paper also discusses the developing application of magnesium die castings in the microelectronics and automotive industries

Free flowing of liquid metal through the gate during die filling and solidification is critical to the final product quality in aluminium high pressure die casting. Early close-off of the gate due ...

The intent of this study was to explore comprehensively the conformational possibilities of a set of DNA-binding peptides containing C-terminal amides (Fig. 1). First, potential peptide conformations were computer generated to determine possible low-energy solution conformations and DNA-binding modes. Second, solid-phase peptide synthesis was used to produce an enantiomeric tetrapeptide library [1] comprised of unnatural amino acids. The solution properties of all 16 possible tetrapeptides were determined by RP-HPLC (Fig. 2a). All of the tetrapeptide amides generated in the library were found to bind to DNA, and their DNAbinding affinities were compared by a novel approach to affinity capillary electrophoretic analysis(ACE) (Fig. 2b).

The role of glutathione in carboplatin ototoxicity was investigated in the chinchilla. Chinchillas hearing was tested with both distortion product otoacoustic emissions (DPOAE) and evoked potentials recorded from a chronic electrode in the inferior colliculus (IC). All subjects had an osmotic pump fitted to their right ear and it received buthionine sulfoximine (BSO) at a dose of 15 mM delivered at 5 ml per hour for 14 days. A group (N=4) was given a double dose of carboplatin (25 mg/kg i.p. for 2 days). The pump was implanted three days before the carboplatin dose. The BSO treated ears showed a greater loss in both evoked potential and DPOAE measures, as well as substantially fewer missing hair cells. The results implicate reactive oxygen species (ROS) as a common factor in ototoxic reactions because suppression of glutathione antioxidant leads to greater ototoxic reactions.

This paper highlights the advantages of warm forming technique to produce thin-walled magnesium parts. The process parameters considered in the feasibility study were forming temperature, in the range of 28°C to 300°C and magnesium sheet (AZ31B-H24) thickness, in the range of 0.4 mm to 1 mm. Magnesium hand phone covers of a thickness down to 0.4 mm have been successfully produced. It was found that the optimum forming temperature is between 225°C and 275°C. Metallograhic examination shows a sound microstructure of the magnesium sheets formed at 250°C.

Cells can die by two distinct pathways: apoptosis and necrosis. To explore whether intense noise can induce hair cell (HC) death via the apoptotic pathway, we systematically examined morphological changes in guinea pig cochlear HC nuclei stained with Hoechst 33342, a fluorescent dye specifically labelling the nuclear DNA. A narrow band noise centred at 4 kHz with levels at 110 dB, 115 dB or 120 dB (SPL) was applied for 4 h and the exposed cochleae were collected at various intervals (3 h, 3 or 14 days) after the noise exposure. Auditory function was monitored by measuring thresholds of auditory brain stem responses. In the noise-damaged cochleae, there were two major types of nuclear changes, nuclear condensation appeared as karyorrhexis or karyopyknosis and nuclear swelling. Karyorrhexis and karyopyknosis predominately appeared in the severely damaged cochlear region in the animals exposed to 120 dB noise and examined 3 h after the noise exposure. In contrast, swelling of nuclei occurred in all of the noise-exposed cochleae, and was the feature change in the animals exposed to 110 and 115 dB noise. This pathological change persisted at least for 14 days after the noise exposure. The typical changes of karyorrhexis and karyopyknosis noted in the animals exposed to 120 dB noise were morphologically similar to those nuclear changes described in previous studies for apoptosis, suggesting that the apoptotic process may be involved in intense noise-induced HC death.

A new isoflavone, named eurycarpin A and a new natural product isoflavone named eurycarpin B have been isolated from the roots of Glycyrrhiza eurycarpa P. C. Li. Their structures were determined to be 7,2',4'-trihydroxy-3'-(3,3-dimethylallyl) isoflavone(I) and 7,2'-dihydroxy-6",6"-dimethylpyrano-(2",3":4',3') isoflavone(II) on the basis of spectroscopic analysis (UV, EI-MS, 1HNMR, 13CNMR, NOE difference and HMBC). In addition, three known isoflavones, licoisoflavone A, calycosin and formononetin, were obtained for the first time from this plant.

Anisodamine is commonly used in clinic as vasodilator. In the present study, the effects of anisodamine on cochlear blood flow were investigated in living guinea pigs using intravital microscopic techniques. The results showed that intravenous infusion of anisodamine (10mg/kg, 5mg/kg, 2 mg/kg) produced a dose dependent reduction in blood pressure. Large dose (10mg/kg) caused significant decrease in blood flow rate to 68.7 +/- 7.4% of the control value with no significant change in vessel diameter. On the other hand, medium and small doses (5mg/kg, 2mg/kg), which produced relatively smaller reduction in blood pressure caused no significant alternation in blood flow rate and vessel diameter. Also, when intramuscular, infusion of anisodamine (2mg/kg) was used no significant difference in blood flow rate, vessel diameter as well as blood pressure were found. The results indicated that increase in cochlear blood supply can not be induced by anisodamine in normal guinea pigs.

A new flavonol glycoside, C27H28O10, mp 151-152 degrees C (MeOH), named acuminatin (I), was isolated from the aerial part of Epimedium acuminatum Franch in addition to four known compounds. By means of UV, FAB-MS, EI-MS, 1HNMR, 13CNMR and chemical evidences, the structure of acuminatin was established as 6", 6"-dimethylpyrano (2", 3": 7, 8) 4'-methyl kaempferol-3-O-alpha-L-rhamnopyranoside. The known compounds were identified as kaempferol-3-O-alpha-L-rhamnopyranoside (II), quercitrin (III), hyperin (IV) and daucosterol (V).

In containing our studies on the flavonoids from Scutellaria amoena C.H. Wright, a new flavanone (I) and six known compounds (II-VII) were isolated from the roots of this plant. On the basis of spectroscopic analysis (UV, 1H NMR, 13C NMR, MS and CD) and chemical evidence, the structure of the new compound was elucidated as (2S) -2',5,6'-trihydroxy-7-methoxyflavanone (I) and named scuteamoenin, the other six known compounds were identified as (2R,3R) -3,5,7-trihydroxyflavanone (II), 2',3,5,6,7-pentahydroxyflavone (III), 2',5,7-trihydroxy-6-methoxyflavone (IV), skullcaflavone II (V), chrysin (VI) and beta-sitosterol (VII) respectively. Compounds II-VII were obtained from this plant for the first time.

We report a design procedure and performance of a voltage amplifier using commercially available GaAs metal-semiconductor field-effect transistors. There are two stages: a common-source amplifier that provides a moderate gain, followed by a common-drain stage for driving the 50Ω coaxial cable. The overall voltage gain measured at 4.2K with a 50Ω load is 3.3, with a bandwidth of 36MHz. The input-referred voltage noise is measured to be approximately 3.2nV∕√Hz in a wide frequency range.

We report the successful molecular‐beam epitaxy growth of high quality CdTe/Cd1−xMgxTe quantum wells (x=0.27–0.52) on GaAs (100) and (111)B substrates. The effectiveness of the two different buffer layers for providing nearly lattice‐matched templates were verified by x‐ray diffraction and photoluminescence. Optical properties of excitons in the above quantum wells were investigated. It is observed that, for the (100) sample, the exciton displays double peaks, the peak splitting originating from exciton localization on the monolayer fluctuation of the quantum well width. Our experiments indicate that the influence of such fluctuations can be reduced, and interfaces of exceptional perfection can be obtained by growth of the CdTe/CdMgTe quantum well structures on GaAs (111)B‐oriented substrates or by a combined growth of conventional molecular‐beam epitaxy and migration‐enhanced epitaxy on GaAs (100)‐oriented substrate. The photoluminescence spectra indicate that significant reduction of the influence of th...

Optical absorption spectra have been measured from 6 to 296 K for a GaAs/AlAs multiple quantum well sample which shows a strong peak at 11.1 μm at room temperature. These and previously published results are compared with predictions of an effective mass model which takes into account conduction‐band nonparabolicity.

From the root of Scutellaria amoena C.H. Wright, two new flavonoids (I, II) and six known flavonoids (III-VIII) were isolated. On the basis of spectroscopic analysis (UV, 1HNMR, 13CNMR, MS and CD) and chemical evidences, the structures of I and II were elucidated as (2S)-2',5,6'-trihydroxy-7-methoxyflavanone-2'-O-beta-D-glucopyrano side (I) and (2R, 3R)-2',3,5,7-tetrahydroxyflavanone (II) respectively. The other six known compounds were identified as (2S)-5,7,8-trihydroxyflavanone (III), (2S)-2',5,6',7-tetrahydroxyflavanone (IV), (2R, 3R)-2',3,5,6',7-pentahydroxyflavanone (V), 2',5,6',7-tetrahydroxyflavone (VI) norwogonin (VII) and oroxylin-A (VIII) respectively. Compounds III-VIII were obtained from this plant for the first time.