1,038 research outputs found

    A comprehensive analysis of Fermi Gamma-Ray Burst Data: IV. Spectral lag and Its Relation to Ep Evolution

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    The spectral evolution and spectral lag behavior of 92 bright pulses from 84 gamma-ray bursts (GRBs) observed by the Fermi GBM telescope are studied. These pulses can be classified into hard-to-soft pulses (H2S, 64/92), H2S-dominated-tracking pulses (21/92), and other tracking pulses (7/92). We focus on the relationship between spectral evolution and spectral lags of H2S and H2S-dominated-tracking pulses. %in hard-to-soft pulses (H2S, 64/92) and H2S-dominating-tracking (21/92) pulses. The main trend of spectral evolution (lag behavior) is estimated with logEpkElog(t+t0)\log E_p\propto k_E\log(t+t_0) (τ^kτ^logE{\hat{\tau}} \propto k_{\hat{\tau}}\log E), where EpE_p is the peak photon energy in the radiation spectrum, t+t0t+t_0 is the observer time relative to the beginning of pulse t0-t_0, and τ^{\hat{\tau}} is the spectral lag of photons with energy EE with respect to the energy band 88-2525 keV. For H2S and H2S-dominated-tracking pulses, a weak correlation between kτ^/Wk_{{\hat{\tau}}}/W and kEk_E is found, where WW is the pulse width. We also study the spectral lag behavior with peak time tpEt_{\rm p_E} of pulses for 30 well-shaped pulses and estimate the main trend of the spectral lag behavior with logtpEktplogE\log t_{\rm p_E}\propto k_{t_p}\log E. It is found that ktpk_{t_p} is correlated with kEk_E. We perform simulations under a phenomenological model of spectral evolution, and find that these correlations are reproduced. We then conclude that spectral lags are closely related to spectral evolution within the pulse. The most natural explanation of these observations is that the emission is from the electrons in the same fluid unit at an emission site moving away from the central engine, as expected in the models invoking magnetic dissipation in a moderately-high-σ\sigma outflow.Comment: 58 pages, 11 figures, 3 tables. ApJ in pres

    catena-Poly[[iodidocopper(I)]-μ-4,4′,6,6′-tetra­methyl-2,2′-(ethyl­enedithio)dipyrimidine-κ2 N:N′]

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    In the title coordination polymer, [CuI(C14H18N4S2)]n, the CuI center is trigonally coordinated by two pyrimidine N-atom donors from two distinct dithio­ether ligands and one iodide anion. The Cu and I atoms are located on a twofold axis, whereas the midpoint of the central C—C bond of the dithio­ether ligand is located on an inversion center. Each organic ligand, acting in a bidentate mode, bridges two CuI ions, resulting in the formation of polymeric zigzag chains. The dihedral angle between the two pyrimidine units bonded to the metal center is 88.01 (2)°. The crystal packing is mainly stabilized by van der Waals forces and π–π stacking inter­actions, with an inter­planar distance between the pyrimidine rings of adjacent chains of 3.638 (3) Å

    The effects of extracts of atractylodes macrocephala koidz combined with transcutaneous electrical acupoint stimulation in treating the ovariectomized female rats

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    Background: The present study was to explore the effects of the extracts of Atractylodes macrocephala Koidz (EAMK) combined with transcutaneous electrical acupoint stimulation (TEAS) on the ovariectomized female rats.Materials and Methods: Forty female Sprague-Dawley rats were randomly divided into four groups: sham-operation, model, livial and EAMK+TEAS groups (n=10 in each group). After the individual treatments for 8 weeks ended, the serum levels of estradiol (E2), follicle stimulating hormone (FSH), luteinizing hormone (LH), osteocalcin and interleukin-6 (IL-6) were measured with commercial enzyme-linked immunosorbent assay.Results: We found that in the sham-operation group, the serum E2 and osteocalcin levels were significantly higher, and the serum levels of FSH, LH and IL-6 were markedly lower than those of other groups (P<0.05). No significant differences existed between the livial and EAMK+TEAS groups on the serum E2 and osteocalcin levels (P>0.05), however, the serum FSH and IL-6 levels of EAMK+TEAS group were significantly lower than those of the livial group (P<0.05).Conclusion: EAMK combined with TEAS has promises in treating the ovariectomized female rats.Key words: Extracts of Atractylodes macrocephala Koidz (EAMK), transcutaneous electrical acupoint stimulation (TEAS), osteocalcin, interleukin-6 (IL-6)

    Chlorido[6-phenyl-4-(p-tol­yl)-2,2′-bipyridyl-κ2 N,N′]platinum(II)

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    The asymmetric unit of the title compound, [Pt(C23H17N2)Cl], contains two independent mol­ecules with distinct dihedral angles between the central pyridyl and methylbenzene rings [7.77 (2) and 24.07 (2)°]. Short inter­molecular distances [3.582 (6) and 3.600 (6) Å] between the outer pyridine and the PtNC3 and PtN2C2 rings, respectively, indicate the existence of π–π inter­actions, which link the mol­ecules into stacks along the a axis. The crystal structure is further stabilized by weak C—H⋯π inter­actions

    A Pilot Trial Assessing Urinary Gene Expression Profiling with an mRNA Array for Diabetic Nephropathy

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    BACKGROUND: The initiation and progression of diabetic nephropathy (DN) is complex. Quantification of mRNA expression in urinary sediment has emerged as a novel strategy for studying renal diseases. Considering the numerous molecules involved in DN development, a high-throughput platform with parallel detection of multiple mRNAs is needed. In this study, we constructed a self-assembling mRNA array to analyze urinary mRNAs in DN patients with aims to reveal its potential in searching novel biomarkers. METHODS: mRNA array containing 88 genes were fabricated and its performance was evaluated. A pilot study with 9 subjects including 6 DN patients and 3 normal controls were studied with the array. DN patients were assigned into two groups according to their estimate glomerular rate (eGFR): DNI group (eGFR>60 ml/min/1.73 m(2), n = 3) and DNII group (eGFR<60 ml/min/1.73 m(2), n = 3). Urinary cell pellet was collected from each study participant. Relative abundance of these target mRNAs from urinary pellet was quantified with the array. RESULTS: The array we fabricated displayed high sensitivity and specificity. Moreover, the Cts of Positive PCR Controls in our experiments were 24±0.5 which indicated high repeatability of the array. A total of 29 mRNAs were significantly increased in DN patients compared with controls (p<0.05). Among these genes, α-actinin4, CDH2, ACE, FAT1, synaptopodin, COL4α, twist, NOTCH3 mRNA expression were 15-fold higher than those in normal controls. In contrast, urinary TIMP-1 mRNA was significantly decreased in DN patients (p<0.05). It was shown that CTGF, MCP-1, PAI-1, ACE, CDH1, CDH2 mRNA varied significantly among the 3 study groups, and their mRNA levels increased with DN progression (p<0.05). CONCLUSION: Our pilot study demonstrated that mRNA array might serve as a high-throughput and sensitive tool for detecting mRNA expression in urinary sediment. Thus, this primary study indicated that mRNA array probably could be a useful tool for searching new biomarkers for DN

    THE EFFECTS OF EXTRACTS OF ATRACTYLODES MACROCEPHALA KOIDZ COMBINED WITH TRANSCUTANEOUS ELECTRICALACUPOINT STIMULATION IN TREATING THE OVARIECTOMIZED FEMALE RATS

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    Background: The present study was to explore the effects of the extracts of Atractylodes macrocephala Koidz (EAMK) combined with transcutaneous electrical acupoint stimulation (TEAS) on the ovariectomized female rats. Materials and Methods: Forty female Sprague-Dawley rats were randomly divided into four groups: sham-operation, model, livial and EAMK+TEAS groups (n=10 in each group). After the individual treatments for 8 weeks ended, the serum levels of estradiol (E2), follicle stimulating hormone (FSH), luteinizing hormone (LH), osteocalcin and interleukin-6 (IL-6) were measured with commercial enzyme-linked immunosorbent assay. Results: We found that in the sham-operation group, the serum E2 and osteocalcin levels were significantly higher, and the serum levels of FSH, LH and IL-6 were markedly lower than those of other groups (P0.05), however, the serum FSH and IL-6 levels of EAMK+TEAS group were significantly lower than those of the livial group (

    The Effects of Velvet Antler of Deer on Cardiac Functions of Rats with Heart Failure following Myocardial Infarction

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    Velvet antler of deer (VAD) is a commonly-used kidney-Yang supplementing traditional Chinese medication. According to the heart-kidney-related theory, heart Yang originates in kidney Yang and heart failure due to heart Yang deficiency can be treated by tonifying kidney Yang. In this study, we investigated therapeutic effects of VAD on cardiac functions in rats with heart failure following myocardial infarction. Forty-eight male Wistar rats were subjected either to left coronary artery ligation (N = 36) or to sham operation (N = 12). One week after the surgery, rats with heart failure received daily treatment of double-distilled water, captopril or VAD by gavage for consecutively four weeks, while sham-operated animals were given double-distilled water. Ultrasonic echocardiography was adopted to examine cardiac structural and functional parameters and serum brain natriuretic peptide (BNP) concentration was measured using radioimmunoassay. We found that VAD partially reversed changes in cardiac functional parameters and serum BNP levels in rats with heart failure. These results provide further evidence for the heart-kidney-related theory and suggest that VAD might be a potentially alternative and complementary medicine for the treatment of heart failure

    Complete sequence and organization of Antheraea pernyi nucleopolyhedrovirus, a dr-rich baculovirus

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    <p>Abstract</p> <p>Background</p> <p>The completion and reporting of baculovirus genomes is extremely important as it advances our understanding of gene function and evolution. Due to the large number of viral genomes now sequenced it is very important that authors present significantly detailed analyses to advance the understanding of the viral genomes. However, there is no report of the <it>Antheraea pernyi </it>nucleopolyhedrovirus (AnpeNPV) genome.</p> <p>Results</p> <p>The genome of AnpeNPV, which infects Chinese tussah silkworm (<it>Antheraea pernyi</it>), was sequenced and analyzed. The genome was 126,629 bp in size. The G+C content of the genome, 53.4%, was higher than that of most of the sequenced baculoviruses. 147 open reading frames (ORFs) that putatively encode proteins of 50 or more amino acid residues with minimal overlap were determined. Of the 147 ORFs, 143 appeared to be homologous to other baculovirus genes, and 4 were unique to AnpeNPV. Furthermore, there are still 29 and 33 conserved genes present in all baculoviruses and all lepidopteran baculoviruses respectively. In addition, the total number of genes common to all lepidopteran NPVs is sill 74, however the 74 genes are somewhat different from the 74 genes identified before because of some new sequenced NPVs. Only 6 genes were found exclusively in all lepidopteran NPVs and 12 genes were found exclusively in all Group I NPVs. AnpeNPV encodes <it>v-trex</it>(Anpe115, a 3' to 5' repair exonuclease), which was observed only in CfMNPV and CfDEFNPV in Group I NPVs. This gene potentially originated by horizontal gene transfer from an ancestral host. In addition, AnpeNPV encodes two <it>conotoxin</it>-like gene homologues (<it>ctls</it>), <it>ctl1 </it>and <it>ctl2</it>, which were observed only in HycuNPV, OpMNPV and LdMNPV. Unlike other baculoviruses, only 3 typical homologous regions (<it>hr</it>s) were identified containing 2~9 repeats of a 30 bp-long palindromic core. However, 24 perfect or imperfect direct repeats (<it>dr</it>s) with a high degree of AT content were found within the intergenic spacer regions that may function as non-<it>hr</it>, <it>ori</it>-like regions found in GrleGV, CpGV and AdorGV. 9 <it>dr</it>s were also found in intragenic spacer regions of AnpeNPV.</p> <p>Conclusion</p> <p>AnpeNPV belongs to Group I NPVs and is most similar to HycuNPV, EppoNPV, OpMNPV and CfMNPV based on gene content, genome arrangement, and amino acid identity. In addition, analysis of genes that flank <it>hr</it>s supported the argument that these regions are involved in the transfer of sequences between the virus and host.</p
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