102 research outputs found
Can a dog be jealous?
Whether humans alone experience complex emotions like jealousy or envy remains hotly debated, partly because of the difficulty of measuring them without a verbal report. Cook, Berns and colleagues use functional brain imaging to identify in dogs neural responses very similar to those evoked by jealousy in humans. When dogs see their caregiver reward a facsimile dog, their amygdala is activated and the strength of this response predicts aggressive behavior — just as jealousy leads to aggression in humans. The authors conclude that dogs feel something very similar to human jealousy. This novel and creative study tackles one of the most vexing challenges in neuroscience — understanding the unstated thoughts and feelings of others — with practical applications that go beyond getting closer to man’s best friend. The issue of whether a dog can be jealous nevertheless remains far from settled, as we discuss below
Mechanism investigation on the formation of olefins and paraffin from the thermochemical catalytic conversion of triglycerides catalyzed by alkali metal catalysts
Triglycerides are a promising biomass feedstock that can be used for production of organic hydrocarbons including long-chain olefins and paraffin. The challenge for this production process lies on the lack of a clear mechanism of the conversion process. In this work, the conversion mechanism from triglycerides to olefins and paraffin using alkali metal catalysts was investigated adopting both computational calculations using density functional theory and experimental studies. The bond dissociation energies of the main bonds were calculated, especially for the α carbon‑carbon bond, which leads to effective removal of carboxyl groups during the thermochemical conversion process. The dynamic behavior of triglycerides catalyzed by alkali metal catalysts was also investigated using thermogravimetric analysis, which found that Li ion has lowest activation energy below 200 kJ/mol when compared with the other alkali ions studied. The catalytic conversion mechanism was proposed in this work based on the results obtained from TG-IR, GC, GC–MS and XRD analyses. The O atoms are removed in the form of CO, CO2 and H2O, product M + O and M+, which generates M2CO3. A more detailed mechanism has been proposed in this paper, which has significance toward guiding the cleavage of triglycerides to produce long‑carbon-chain terminal olefins and normal paraffin
NF-ÎşB and Snail1a coordinate the cell cycle with gastrulation
The cell cycle needs to strictly coordinate with developmental processes to ensure correct generation of the body plan and different tissues. However, the molecular mechanism underlying the coordination remains largely unknown. In this study, we investigate how the cell cycle coordinates gastrulation cell movements in zebrafish. We present a system to modulate the cell cycle in early zebrafish embryos by manipulating the geminin-Cdt1 balance. Alterations of the cell cycle change the apoptotic level during gastrulation, which correlates with the nuclear level of antiapoptotic nuclear factor ÎşB (NF-ÎşB). NF-ÎşB associates with the Snail1a promoter region on the chromatin and directly activates Snail1a, an important factor controlling cell delamination, which is the initial step of mesendodermal cell movements during gastrulation. In effect, the cell cycle coordinates the delamination of mesendodermal cells through the transcription of Snail1a. Our results suggest a molecular mechanism by which NF-ÎşB and Snail1a coordinate the cell cycle through gastrulation
Potential of Core-Collapse Supernova Neutrino Detection at JUNO
JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve
Detection of the Diffuse Supernova Neutrino Background with JUNO
As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO
Real-time Monitoring for the Next Core-Collapse Supernova in JUNO
Core-collapse supernova (CCSN) is one of the most energetic astrophysical
events in the Universe. The early and prompt detection of neutrinos before
(pre-SN) and during the SN burst is a unique opportunity to realize the
multi-messenger observation of the CCSN events. In this work, we describe the
monitoring concept and present the sensitivity of the system to the pre-SN and
SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is
a 20 kton liquid scintillator detector under construction in South China. The
real-time monitoring system is designed with both the prompt monitors on the
electronic board and online monitors at the data acquisition stage, in order to
ensure both the alert speed and alert coverage of progenitor stars. By assuming
a false alert rate of 1 per year, this monitoring system can be sensitive to
the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos
up to about 370 (360) kpc for a progenitor mass of 30 for the case
of normal (inverted) mass ordering. The pointing ability of the CCSN is
evaluated by using the accumulated event anisotropy of the inverse beta decay
interactions from pre-SN or SN neutrinos, which, along with the early alert,
can play important roles for the followup multi-messenger observations of the
next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure
Perceptual decision related activity in the parallel pathways of the lateral geniculate nucleus (LGN)
Can a dog be jealous?
Whether humans alone experience complex emotions like jealousy or envy remains hotly debated, partly because of the difficulty of measuring them without a verbal report. Cook, Berns and colleagues use functional brain imaging to identify in dogs neural responses very similar to those evoked by jealousy in humans. When dogs see their caregiver reward a facsimile dog, their amygdala is activated and the strength of this response predicts aggressive behavior — just as jealousy leads to aggression in humans. The authors conclude that dogs feel something very similar to human jealousy. This novel and creative study tackles one of the most vexing challenges in neuroscience — understanding the unstated thoughts and feelings of others — with practical applications that go beyond getting closer to man’s best friend. The issue of whether a dog can be jealous nevertheless remains far from settled, as we discuss below
Construction of FasL siRNA expression vector and its expression in lung cancer cell line A549
Background and objective Fas/FasL is a member of Tumor Necrosis Factor (TNF) super family and related to tumor cell apoptosis. It is hypothesis by forward study that activated lymphocytes is more sensitive with Fas/FasL due to up-regulation of FasL expression, so it can be inverse killedly and cleared by tumor cell. The aim of this investigate is to study the fuction of FasL gene and gene therapy of lung cancer by to down-regulationg the FasL gene expression with a siRNA expression plasmid in lung cancer cell A549 as well as its inverse killing effect between activated T lymphocytes and lung cancer cell A549. Methods Potential RNAi oligonucleotides of FasL was designed and synthesized according to appropriate web site. Then a FasL siRNA plasmid was constructed using a pGCsi-U6 vector.The plasmid was sequenced to confirm the inserted sequence. Western blot analysis was used to assess the levels of FasL proteins after the constructed plasmids have been transfected into A549 cells. Results It was confirmed by sequencing that the plasmid was constructed successfully. The result of Western blot clearly showed that FasL siRNA plasmid inhibited FasL expression in A549 cells. Conclusion The construct of FasL siRNA plasmid is successful. FasL protein expression of A549 cell is effectively inhibited by RNAi
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