177 research outputs found
ASSESSING THE RESPONSE OF FARM HOUSEHOLDS TO DAIRY POLICY REFORM IN ISRAEL
After nearly fifty years of stability and stagnation of dairy market regulations in Israel, a dramatic policy reform has been enacted in 1999. The reform enabled farm households, for the first time, to trade production quotas. In addition, the reform signaled to farmers that milk prices will gradually go down in real terms, and therefore only producers who expand and become more efficient will prevail. The reform allowed for generous financial support for investment in expansion, but also required the adoption of environmental regulations which could be costly to many farm families. This paper uses data from a census of small family-operated dairy enterprises that was conducted in 2001, in order to analyze the response of farm households to the reform. The results imply that the reform was particularly attractive for already strong producers. Weaker producers are less attracted by the reform and will likely fade away by default in the long run. Another finding is that intergenerational succession is an important element of decision making of milk producers. Hence, the response of farm households to changes in the economic environment cannot be disentangled from the occupational decisions of their offspring. These findings imply that the desired structural change in the family-farm milk production sector will take much longer than expected, essentially as long as the current generation of producers is around. This requires, perhaps, an extension of the reform period or a change in incentives in favor of the smaller and older producers.milk policy reform, technology adoption, intergenerational succession, Agricultural and Food Policy, Livestock Production/Industries,
Assessing the response of farm households to dairy policy reform in Israel
After nearly fifty years of stability and stagnation of dairy market regulations in Israel, a dramatic policy reform has been enacted in 1999. The reform enabled farm households, for the first time, to trade production quotas. In addition, the reform signaled to farmers that milk prices will gradually go down in real terms, and therefore only producers who expand and become more efficient will prevail. The reform allowed for generous financial support for investment in expansion, but also required the adoption of environmental regulations which could be costly to many farm families. This paper uses data from a census of small family-operated dairy enterprises that was conducted in 2001, in order to analyze the response of farm households to the reform. The results imply that the reform was particularly attractive for already strong producers. Weaker producers are less attracted by the reform and will likely fade away by default in the long run. Another finding is that intergenerational succession is an important element of decision making of milk producers. Hence, the response of farm households to changes in the economic environment cannot be disentangled from the occupational decisions of their offspring. These findings imply that the desired structural change in the family-farm milk production sector will take much longer than expected, essentially as long as the current generation of producers is around. This requires, perhaps, an extension of the reform period or a change in incentives in favor of the smaller and older producers
The Eliashberg Function of Amorphous Metals
A connection is proposed between the anomalous thermal transport properties
of amorphous solids and the low-frequency behavior of the Eliashberg function.
By means of a model calculation we show that the size and frequency dependence
of the phonon mean-free-path that has been extracted from measurements of the
thermal conductivity in amorphous solids leads to a sizeable linear region in
the Eliashberg function at small frequencies. Quantitative comparison with
recent experiments gives very good agreement.Comment: 4pp., REVTeX, 1 uuencoded ps fig. Original posting had a corrupted
raw ps fig appended. Published as PRB 51, 689 (1995
Dynamic Scaling of Magnetic Flux Noise Near the KTB Transition in Overdamped Josephson Junction Arrays
We have used a dc Superconducting QUantum Interference Device to measure the
magnetic flux noise generated by the equilibrium vortex density fluctuations
associated with the Kosterlitz-Thouless-Berezinskii (KTB) transition in an
overdamped Josephson junction array. At temperatures slightly above the KTB
transition temperature, the noise is white for and scales as
for . Here , where is the correlation
length and is the dynamic exponent. Moreover, when all frequencies are
scaled by , data for different temperatures and frequencies collapse on
to a single curve. In addition, we have extracted the dynamic exponent and
found .Comment: 5 pages, LaTeX (REVTeX) format, requires epsfig and amstex style
files. 3 figures included. Tentatively scheduled for publication in Physical
Review Letters, 18 March, 199
Supercomputer Simulations of Disk Galaxies
The time evolution of models for an isolated disk of highly flattened
galaxies of stars is investigated by direct integration of the Newtonian
equations of motion of N=30,000 identical stars over a time span of many
galactic rotations. Certain astronomical implications of the simulations to
actual disk-shaped (i.e. rapidly rotating) galaxies are explored as well.Comment: 3 pages, 2 figure Aat.sty, Aattable.sty, presented by E. Griv at the
JENAM 2000, S02, Moscow, Russia, 200
Critical Exponents of the Fully Frustrated 2-D Xy Model
We present a detailed study of the critical properties of the 2-D XY model
with maximal frustration in a square lattice. We use extensive Monte Carlo
simulations to study the thermodynamics of the spin and chiral degrees of
freedom, concentrating on their correlation functions. The gauge invariant
spin-spin correlation functions are calculated close to the critical point for
lattice sizes up to ; the chiral correlation functions are
studied on lattices up to . We find that the critical exponents of
the spin phase transition are , and , which are to be
compared with the unfrustrated XY model exponents and . We
also find that the critical exponents of the chiral transition are
, , , and
, which are different from the expected 2-D Ising
critical exponents. The spin-phase transition occurs at which
is about 7\% above the estimated chiral critical temperature . However, because of the size of the statistical errors, it is
difficult to decide with certainty whether the transitions occur at the same or
at slightly different temperatures. Finally, the jump in the helicity modulus
in the fully frustrated system is found to be about 23\% below the unfrustrated
universal value. The most important consequence of these results is that the
fully frustrated XY model appears to be in a novel universality class. Recent
successful comparisons of some of these results with experimental data are also
briefly discussed. (TO APPEAR IN PRB)Comment: 47 pages (PHYZZX
Severe Exercise and Exercise Training Exert Opposite Effects on Human Neutrophil Apoptosis via Altering the Redox Status
Neutrophil spontaneous apoptosis, a process crucial for immune regulation, is mainly controlled by alterations in reactive oxygen species (ROS) and mitochondria integrity. Exercise has been proposed to be a physiological way to modulate immunity; while acute severe exercise (ASE) usually impedes immunity, chronic moderate exercise (CME) improves it. This study aimed to investigate whether and how ASE and CME oppositely regulate human neutrophil apoptosis. Thirteen sedentary young males underwent an initial ASE and were subsequently divided into exercise and control groups. The exercise group (n = 8) underwent 2 months of CME followed by 2 months of detraining. Additional ASE paradigms were performed at the end of each month. Neutrophils were isolated from blood specimens drawn at rest and immediately after each ASE for assaying neutrophil spontaneous apoptosis (annexin-V binding on the outer surface) along with redox-related parameters and mitochondria-related parameters. Our results showed that i) the initial ASE immediately increased the oxidative stress (cytosolic ROS and glutathione oxidation), and sequentially accelerated the reduction of mitochondrial membrane potential, the surface binding of annexin-V, and the generation of mitochondrial ROS; ii) CME upregulated glutathione level, retarded spontaneous apoptosis and delayed mitochondria deterioration; iii) most effects of CME were unchanged after detraining; and iv) CME blocked ASE effects and this capability remained intact even after detraining. Furthermore, the ASE effects on neutrophil spontaneous apoptosis were mimicked by adding exogenous H2O2, but not by suppressing mitochondrial membrane potential. In conclusion, while ASE induced an oxidative state and resulted in acceleration of human neutrophil apoptosis, CME delayed neutrophil apoptosis by maintaining a reduced state for long periods of time even after detraining
Chromosomal location of human genes encoding major heat-shock protein HSP70
The HSP70 family of heat-shock proteins constitutes the major proteins synthesized in response to elevated temperatures and other forms of stress. In eukaryotes members of the HSP70 family also include a protein similar if not identical to bovine brain uncoating ATPase and glucose-regulated proteins. An intriguing relation has been established between expression of heat-shock proteins and transformation in mammalian cells. Elevated levels of HSP70 are found in some transformed cell lines, and viral and cellular gene products that are capable of transforming cells in vitro can also stimulate transcription of HSP70 genes. To determine the organization of this complex multigene family in the human genome, we used complementary approaches: Southern analysis and protein gels of Chinese hamster-human somatic cell hybrids, and in situ hybridization to human chromosomes. We demonstrate that functional genes encoding HSP70 proteins map to human chromosomes 6, 14, 21, and at least one other chromosome .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45535/1/11188_2005_Article_BF01534692.pd
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