5,909 research outputs found
Time-asymmetry of probabilities versus relativistic causal structure: an arrow of time
There is an incompatibility between the symmetries of causal structure in
relativity theory and the signaling abilities of probabilistic devices with
inputs and outputs: while time-reversal in relativity will not introduce the
ability to signal between spacelike separated regions, this is not the case for
probabilistic devices with space-like separated input-output pairs. We
explicitly describe a non-signaling device which becomes a perfect signaling
device under time-reversal, where time-reversal can be conceptualized as
playing backwards a videotape of an agent manipulating the device. This leads
to an arrow of time that is identifiable when studying the correlations of
events for spacelike separated regions. Somewhat surprisingly, although
time-reversal of Popuscu-Roerlich boxes also allows agents to signal, it does
not yield a perfect signaling device. Finally, we realize time-reversal using
post-selection, which could lead experimental implementation.Comment: 4 pages, some figures; replaces arXiv:1010.4572 [quant-ph
Anomalous thermoelectric power of Mg1-xAlxB2 system with x = 0.0 to 1.0
Thermoelectric power, S(T) of the Mg1-xAlxB2 system has been measured for x =
0.0, 0.1, 0.2, 0.4, 0.6, 0.8 and 1.0. XRD, resistivity and magnetization
measurements are also presented. It has been found that the thermoelectric
power is positive for x = 0.4 and is negative for x = 0.6 over the entire
temperature range studied up to 300 K. The thermoelectric power of x = 0.4
samples vanishes discontinuously below a certain temperature, implying
existence of superconductivity. In general, the magnitude of the thermoelectric
power increases with temperature up to a certain temperature, and then it
starts to decrease towards zero base line. In order to explain the observed
behavior of the thermoelectric power, we have used a model in which both
diffusion and phonon drag processes are combined by using a phenomenological
interpolation between the low and high temperature behaviors of the
thermoelectric power. The considered model provides an excellent fit to the
observed data. It is further found that Al doping enhances the Debye
temperature.Comment: 19 pages Text + Figs.
suggestions/comments([email protected]
Effect of planting geometry and training on growth and seed yield of tomato (Solanum lycopersicum L.)
The study was conducted to evaluate the effect of planting geometry and training on growth and seed yield of tomato (Solanum lycopersicum L.) using cultivar Solan Lalima during Kharif 2013 at Experimental Farm of Department of Seed Science and Technology, Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni, Solan (H.P.). The treatments comprised of four training levels i.e. Y1 (single stem), Y2 (double stem), Y3 (unpruned with horizontal string) and Y4 (unpruned bush stakes (control)) and eight plant densities viz. S1 (60Ă—15 cm), S2 (60+30Ă—15 cm), S3 (60Ă—30 cm), S4 (60+30Ă—30 cm), S5 (90Ă—15 cm), S6 (90+30Ă—15 cm), S7 (90Ă—30 cm) and S8 (90+30Ă—30 cm). Analysis of variance showed that the treatment combination Y1S7 (single stem and plant spaced at 90Ă—30 cm) resulted in maximum ripe fruit length and width (5.86 cm and 5.06 cm, respectively), maximum number of seeds/fruit (110.67), minimum days to ripe fruit harvest (71.00) and maximum harvest duration (59.84 days) but gave the low seed yield. The combination Y2S5 (double stem and 90Ă—15 cm) resulted highest seed yield i.e. 519.71 kg per hectare. Therefore, planting density S5 (90x15 cm) in combination with training system Y2 (double stem) may be recommended for commercial seed production of tomato
Complex diffuse radio emission in the merging PLANCK ESZ cluster Abell 3411
We present VLA radio and Chandra X-ray observations of the merging galaxy
cluster Abell 3411. For the cluster, we find an overall temperature of 6.4 keV
and an X-ray luminosity of 2.8 x 10^{44} erg s^{-1} between 0.5 and 2.0 keV.
The Chandra observation reveals the cluster to be undergoing a merger event.
The VLA observations show the presence of large-scale diffuse emission in the
central region of the cluster, which we classify as a 0.9 Mpc size radio halo.
In addition, a complex region of diffuse, polarized emission is found in the
southeastern outskirts of the cluster, along the projected merger axis of the
system. We classify this region of diffuse emission as a radio relic. The total
extent of this radio relic is 1.9 Mpc. For the combined emission in the cluster
region, we find a radio spectral index of -1.0 \pm 0.1 between 74 MHz and 1.4
GHz. The morphology of the radio relic is peculiar, as the relic is broken up
into five fragments. This suggests that the shock responsible for the relic has
been broken up due to interaction with a large-scale galaxy filament connected
to the cluster or other substructures in the ICM. Alternatively, the complex
morphology reflects the presence of electrons in fossil radio bubbles that are
re-accelerated by a shock.Comment: Accepted for publication in ApJ, 8 pages, 5 figure
Tautomeric mutation: A quantum spin modelling
A quantum spin model representing tautomeric mutation is proposed for any DNA
molecule. Based on this model, the quantum mechanical calculations for
mutational rate and complementarity restoring repair rate in the replication
processes are carried out. A possible application to a real biological system
is discussed.Comment: 7 pages (no figures
Wireless Controlled Door-Bell
Now-a- day\u27s wireless control of appliance is in practice, because of its advantage like no wire is needed, multiple controlling is less complicated. The controlling range of wireless doorbell is 100M.
As the wireless doorbell is wireless based project, it is divided into two major section i.e. transmitter and receiver.
Transmitter: This transmitter section is designed around oscillator transistor (BF194B) T2 followed by two transistor (BC148) T1 and T3. Transistor T2 generate special radio frequency determined by trimmer (variable capacitor) and coil. Transistor T1 is used as pulse generator. The output from transistor T3 is given to emitter of transistor T2 in order to get radio frequency from its collector. Trimmer VC1 is used to adjust the transmitter frequency.
Receiver: The receiver section is further divided into two main sections i.e. RF amplifier section and bell trigger section. An aerial is used to receive the transmitted frequency from remote which is further amplified by amplifier and trigger circuit. The whole receiver circuit utilizes seven transistors
Geographical Concentration of Rural Poverty in Bangladesh
This paper was presented at the dialogue on Mapping Poverty for Rural Bangladesh: Implications for Pro-poor Development. The dialogue was organised as part of CPD's ongoing agricultural policy research and advocacy activities with IRRI under the PETRRA project. The study reported geographical concentration of rural poverty in Bangladesh for 425 upazilas in 2000-01. The study measured and mapped incidence of poverty (using Headcount Index), intensity of poverty (using Poverty Gap Index) and severity of poverty (using Squared Poverty Gap Index). It has analyzed factors contributing to the spatial concentration of poverty. It is hoped that the findings of the study would be helpful in identifying target areas and priorities for agricultural R&D interventions and poverty reduction programmes.Poverty, Rural Poverty, Bangladesh
Trust and transparency in times of crisis: Results from an online survey during the first wave (April 2020) of the COVID-19 epidemic in the UK
BACKGROUND: The success of a government's COVID-19 control strategy relies on public trust and broad acceptance of response measures. We investigated public perceptions of the UK government's COVID-19 response, focusing on the relationship between trust and perceived transparency, during the first wave (April 2020) of the COVID-19 pandemic in the United Kingdom. METHODS: Anonymous survey data were collected (2020-04-06 to 2020-04-22) from 9,322 respondents, aged 20+ using an online questionnaire shared primarily through Facebook. We took an embedded-mixed-methods approach to data analysis. Missing data were imputed via multiple imputation. Binomial & multinomial logistic regression were used to detect associations between demographic characteristics and perceptions or opinions of the UK government's response to COVID-19. Structural topic modelling (STM), qualitative thematic coding of sub-sets of responses were then used to perform a thematic analysis of topics that were of interest to key demographic groups. RESULTS: Most respondents (95.1%) supported government enforcement of behaviour change. While 52.1% of respondents thought the government was making good decisions, differences were apparent across demographic groups, for example respondents from Scotland had lower odds of responding positively than respondents in London. Higher educational levels saw decreasing odds of having a positive opinion of the government response and decreasing household income associated with decreasing positive opinion. Of respondents who thought the government was not making good decisions 60% believed the economy was being prioritised over people and their health. Positive views on government decision-making were associated with positive views on government transparency about the COVID-19 response. Qualitative analysis about perceptions of government transparency highlighted five key themes: (1) the justification of opacity due to the condition of crisis, (2) generalised mistrust of politics, (3) concerns about the role of scientific evidence, (4) quality of government communication and (5) questions about political decision-making processes. CONCLUSION: Our study suggests that trust is not homogenous across communities, and that generalised mistrust, concerns about the transparent use and communication of evidence and insights into decision-making processes can affect perceptions of the government's pandemic response. We recommend targeted community engagement, tailored to the experiences of different groups and a new focus on accountability and openness around how decisions are made in the response to the UK COVID-19 pandemic
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