883 research outputs found
Household socioeconomics, resource use and fish marketing in two thanas of Bangladesh
This is a report of a socioeconomic survey carried out on a sample of households from owners and operators of small waterbodies in two subdistricts in Gazipur, Bangladesh, to find out the benefits of aquaculture if introduced there. The findings indicate that improved aquaculture technology will benefit the owners and operators of the small water bodies, and that low-cost technologies for aquaculture must be promoted among poor and landless people in order for them to adopt aquaculture.Household surveys, Socioeconomics, Sociological aspects, Fish culture, Fishery economics, Fish consumption, Marketing, Bangladesh,
Photoevaporation of the Jovian circumplanetary disk. I. Explaining the orbit of Callisto and the lack of outer regular satellites
Context: The Galilean satellites are thought to have formed from a
circumplanetary disk (CPD) surrounding Jupiter. When it reached a critical
mass, Jupiter opened an annular gap in the solar protoplanetary disk (PPD) that
might have exposed the CPD to radiation from the young Sun or from the stellar
cluster in which the Solar System formed. Aims: We investigate the radiation
field to which the Jovian CPD was exposed during the process of satellite
formation. The resulting photoevaporation of the CPD is studied in this context
to constrain possible formation scenarios for the Galilean satellites and
explain architectural features of the Galilean system. Methods: We constructed
a model for the stellar birth cluster to determine the intracluster
far-ultraviolet (FUV) radiation field. We employed analytical annular gap
profiles informed by hydrodynamical simulations to investigate a range of
plausible geometries for the Jovian gap. We used the radiation thermochemical
code ProDiMo to evaluate the incident radiation field in the Jovian gap and the
photoevaporation of an embedded 2D axisymmetric CPD. Results: We derive the
time-dependent intracluster FUV radiation field for the solar birth cluster
over 10 Myr. We find that intracluster photoevaporation can cause significant
truncation of the Jovian CPD. We determine steady-state truncation radii for
possible CPDs, finding that the outer radius is proportional to the accretion
rate . For CPD accretion rates
yr, photoevaporative truncation explains the lack of additional
satellites outside the orbit of Callisto. For CPDs of mass , photoevaporation can disperse the disk before Callisto
is able to migrate into the Laplace resonance. This explains why Callisto is
the only massive satellite that is excluded from the resonance.Comment: 17 pages, 13 figures, accepted by A&
Integrated sources of entangled photons at telecom wavelength in femtosecond-laser-written circuits
Photon entanglement is an important state of light that is at the basis of
many protocols in photonic quantum technologies, from quantum computing, to
simulation and sensing. The capability to generate entangled photons in
integrated waveguide sources is particularly advantageous due to the enhanced
stability and more efficient light-crystal interaction. Here we realize an
integrated optical source of entangled degenerate photons at telecom
wavelength, based on the hybrid interfacing of photonic circuits in different
materials, all inscribed by femtosecond laser pulses. We show that our source,
based on spontaneous parametric down-conversion, gives access to different
classes of output states, allowing to switch from path-entangled to
polarization-entangled states with net visibilities above 0.92 for all selected
combinations of integrated devices
Broadband and robust optical waveguide devices using coherent tunnelling adiabatic passage
We numerically demonstrate an optical waveguide structure for the coherent tunnelling adiabatic passage of photons. An alternative coupling scheme is used compared to earlier work. We show that a three rib optical waveguide structure is robust to material loss in the intermediate waveguide and variations to the waveguide parameters. We also present a five rib optical waveguide structure that represents a new class of octave spanning power divider
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Media Ownership and Control Law, Economics and Policy in an Indian and International Context
As academics, lawyers, businesses, regulators, and policy-makers in India cast a glance at the international experience, this book examines the legal, economic, and policy issues relating to regulation of ownership and control of media ..
Thermally-Reconfigurable Quantum Photonic Circuits at Telecom Wavelength by Femtosecond Laser Micromachining
The importance of integrated quantum photonics in the telecom band resides on
the possibility of interfacing with the optical network infrastructure
developed for classical communications. In this framework, femtosecond laser
written integrated photonic circuits, already assessed for quantum information
experiments in the 800 nm wavelength range, have great potentials. In fact
these circuits, written in glass, can be perfectly mode-matched at telecom
wavelength to the in/out coupling fibers, which is a key requirement for a
low-loss processing node in future quantum optical networks. In addition, for
several applications quantum photonic devices will also need to be dynamically
reconfigurable. Here we experimentally demonstrate the high performance of
femtosecond laser written photonic circuits for quantum experiments in the
telecom band and we show the use of thermal shifters, also fabricated by the
same femtosecond laser, to accurately tune them. State-of-the-art manipulation
of single and two-photon states is demonstrated, with fringe visibilities
greater than 95%. This opens the way to the realization of reconfigurable
quantum photonic circuits on this technological platform
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Hong Kong Competition Law
This important new book provides a substantive introduction to Hong Kong competition law contained in the new Competition Ordinance as supplemented by the Competition Commission's Guidelines
Consistent dust and gas models for protoplanetary disks : II. Chemical networks and rates
PW acknowledge funding from the EU FP7- 2011 under Grant Agreement nr. 284405. CR also acknowledges funding by the Austrian Science Fund (FWF), project number P24790.Aims. We aim to define a small and large chemical network which can be used for the quantitative simultaneous analysis of molecular emission from the near-IR to the submm. We also aim to revise reactions of excited molecular hydrogen, which are not included in UMIST, to provide a homogeneous database for future applications. Methods. We have used the thermo-chemical disk modeling code ProDiMo and a standard T Tauri disk model to evaluate the impact of various chemical networks, reaction rate databases and sets of adsorption energies on a large sample of chemical species and emerging line fluxes from the near-IR to the submm wavelength range. Results. We find large differences in the masses and radial distribution of ice reservoirs when considering freeze-out on bare or polar ice coated grains. Most strongly the ammonia ice mass and the location of the snow line (water) change. As a consequence molecules associated to the ice lines such as N2H+ change their emitting region; none of the line fluxes in the sample considered here changes by more than 25% except CO isotopologues, CN and N2H+ lines. The three-body reaction N+H2+M plays a key role in the formation of water in the outer disk. Besides that, differences between the UMIST 2006 and 2012 database change line fluxes in the sample considered here by less than a factor of two (a subset of low excitation CO and fine structure lines stays even within 25%); exceptions are OH, CN, HCN, HCO+ and N2H+ lines. However, different networks such as OSU and KIDA 2011 lead to pronounced differences in the chemistry inside 100 au and thus affect emission lines from high excitation CO, OH and CN lines. H2 is easily excited at the disk surface and state-to-state reactions enhance the abundance of CH+ and to a lesser extent HCO+. For sub-mm lines of HCN, N2H+ and HCO+, a more complex larger network is recommended. Conclusions. More work is required to consolidate data on key reactions leading to the formation of water, molecular ions such as HCO+ and N2H+ as well as the nitrogen chemistry. This affects many of the key lines used in the interpretation of disk observations. Differential analysis of various disk models using the same chemical input data will be more robust than the interpretation of absolute fluxes.PostprintPeer reviewe
Internal Quality of Layer Eggs from Traditional Market Majene
Layer egg is a source of animal protein and food products of animal which popular among the public, and become integral part of consumers’ needs. The high of competitive industry in various countries has caused the quality of the exterior and interior become one of the important assessment indicators. However, there are problems that arise in the process of marketing layer eggs is the quality of egg less attention. Egg quality needs to be maintained; thus, the content remains intact and fresh. This study aimed to determine the quality of Layer eggs from the traditional market Majene.The samples used were 90 layer eggs from traditional market Majene. Sample was was carried out using purposive sampling method with the condition that this location is a place where layer eggs are sold to final consumers such as local people can buy directly without any intermediaries. Parameters based on physical quality include egg weight, albumen index, yolk index and haugh unit value. The data obtained was analyzed qualitative descriptively based on laboratory test results. The results showed that egg weight, albumen index, yolk index and haugh value of eggs from traditional market Majene have good quality and safe for consume based on SNI 2008
Addressing Food Insecurity in College: Mapping a Shared Conceptual Framework for Campus Pantries in Michigan
The first known university food pantry started at Michigan State University in 1993. Since then, campus food pantries are more widespread, although little is known about them. The current study examined how college pantries best serve students and foster their success. Twentyâ eight food pantry directors and staff from across sixteen Michigan college campuses engaged in concept mapping, a technique used to examine the interrelationships among concepts understood by stakeholders. Analyses identified six concepts, examined importance of each concept as assigned by participants, and evaluated variation among institutions. Implications for findings and future research directions are discussed.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147046/1/asap12161_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/147046/2/asap12161.pd
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