11,842 research outputs found
Socioeconomic and bioeconomic performance of Philippine fisheries in the recent decades
The fishing industry in the Philippines was tantamount to a marine capture fishery in the 1950s to 1960s. Aquaculture and inland fishery production were not significant. Only during the 1970s did aquaculture and inland capture fisheries contribute significantly to fish production. From 250 000 t fish production in 1951, this increased substantially to 1.6 million t in the 1990s. An average 4.3% was contributed by fisheries to the gross domestic product from 1988 - 98. Fisheries export earnings reached P12 billion in the 1990s. Exports of fishery products include tuna, shrimps, prawns and seaweed. Fishing industry employees in the Philippines are distributed thus: 70% in the municipal (artisanal) sector, 25% in aquaculture and 5% in the commercial sector. Fish and fish products comprise more than 50% of total animal protein intake vis-ñ-vis meat and meat products and poultry. However per capita consumption of food fish decreased from 40 kgĂąâąâyear-1 in 1988 to 36 kg in 1998. In the Philippines, small scale fishing is defined as fishing within municipal waters using fishing vessels of 3 GT or less, or fishing without vessels. In 1948, there were 63 005 fishers rising to 743 544 in 1995. There was a declining trend in catch per unit effort (CPUE) from 2.10 tĂąâąâHP-1 in 1948 to 0.29 tĂąâąâHP-1 in 1985. Time-series data from 1976 - 87 showed that small pelagics accounted for 38% of total catch followed by demersals, 26%; tuna, 16%; seaweeds, 14%; large pelagics, 6% and invertebrates, 9%. The most important fishing gear in terms of contribution to total catch are gillnets (30%), hook and line (24%) and beach seine (8%). Hook and line accounts for almost 60% of tuna catch while hook and line, gillnets, and fish corrals account for 60% of demersal catch. Commercial fishing can be classified into: (a) small scale commercial fishing (fishing with passive or active gear and utilizing vessels of 3.1 GT up to 20 GT); (b) medium-scale commercial fishing (fishing with active gear and utilizing vessels of 20.1 GT up to 150 GT); and (c) large scale commercial fishing (fishing with active gear and vessels of more than 150 GT). In the 1950s the three dominant types of gear were bag net, the trawl (including beam and otter types) and the round haul seine. The larger tonnage category (more than 100 GT) became more significant in the 1980s. There are 35 species comprising 70 - 95% of total commercial fish production grouped as demersals, small pelagics and large pelagics. Roundscads dominated the small pelagics, followed by slipmouth, a demersal species. Declining catches, disappearance of high value species and increasing volume of juveniles are indications that the fishery is biologically over-fished. This translates as declining profit for the fishery sector. It also means that the fishery employs excess labor and utilizes capital that could be used in other economic sectors.Fishery resources, Fishery surveys, Catch/effort, Trawling, Population characteristics, Biomass, Coastal fisheries, Mathematical models, Marine fisheries, Ecosystems, Socioeconomic aspects, Artisanal fishing, Economic benefits, Fishery industry, Capture fishery economics, ISEW, Philippines,
Comments on : diet, physiology and ecology of fossil mammals as inferred from stable carbon and nitrogen isotope biogeochemistry: implications for Pleistocene bears
A detailed study of isotopic relationships in
European Pleistocene ursid teeth have been presented
by Bocherens et al. (1994). We agree with
the resu1ts and broad conclusions derived from the
stable carbon isotope relationships. These are findings
that confirm the previous hypothesis relating
to the diets of Ursus deningeri and Ursus spelaeu
Pleistocene paleoenvironmental evolution at continental middle latitude inferred from carbon and oxygen stable isotope analysis of ostracodes from the Guadix-Baza Basin (Granada, SE Spain)
A representative paleoenvironmental reconstruction of continental middle latitude from ca. 2my to the upper part of Middle
Pleistocene (279±77ky) was obtained from the carbon and oxygen stable isotopes analyzed in ostracode shells (Cyprideis torosa)
recovered in the Guadix-Baza Basin (SE Spain), an intramontaneous closed depression filled by alluvial and lacustrine sediments.
This study was performed along a 356-m-thick composite section, dated previously by paleomagnetism and the amino acid
racemization method. 013C and 0180 profiles reflected changes in temperature, the evaporationJinfill ratio in the water bodies and
the amount of rain. 013C is also affected by changes in plant biomass: periods with high 013C and 0180 values are associated with
warm and dry regimes, and with less vegetation, which, in some cases, coincide with the development of displacive gypsum
crystals, whereas low 013C and 0180 values correlate with cold and humid episodes, which cause more vegetation biomass and,
therefore, increasing the input of isotopically light carbon. Intermediate 0180 values are linked to temperate dry or humid episodes
when they coincide with high or low 013C values, respectively. 86 paleoclimatic events were distinguished in the Pleistocene record
from the 013C and 0180 profiles. From both the statistical analysis of the geochemical data and the geological observations, four
Cold and Humid Long Periods (low 0180) and four Warm and Dry Long Periods (high 0180) were defined. This differs with
respect to the paleoclimatological behavior established for the Northern Hemisphere where during cold periods (glacial), no water
was available while permafrost conditions persisted, whereas in warm episodes (interglacial), higher precipitation rates occurred.
Good correspondences between the Guadix-Baza Basin paleoclimatic record and a marine oxygen-isotope sequence, two
continental cores and other long Mediterranean paleoenvironmental records (pollen sequences from Israel) were found, which
suggested that climate changes in the Guadix-Baza Basin were in tune with global climatic changes
Scale and structure of time-averaging (age mixing) in terrestrial gastropod assemblages from Quaternary eolian deposits of the eastern Canary Islands
Quantitative estimates of time-averaging (age mixing) in gastropod shell accumulations from Quaternary (the late Pleistocene
and Holocene) eolian deposits of Canary Islands were obtained by direct dating of individual gastropods obtained from
exceptionally well-preserved dune and paleosol shell assemblages. A total of 203 shells of the gastropods Theba geminata and
T. arinagae, representing 44 samples (= strati graphic horizons) from 14 sections, were dated using amino acid (isoleucine)
epimerization ratios calibrated with 12 radiocarbon dates. Most samples reveal a substantial variation in shell age that exceeds the
error that could be generated by dating imprecision, with the mean within-sample shell age range of 6670 years and the mean
standard deviation of 2920 years. Even the most conservative approach (Monte Carlo simulations with a non-sequential Bonferroni
correction) indicates that at least 25% of samples must have undergone substantial time-averaging (e.g., age variations within those
samples cannot be explained by dating imprecision alone). Samples vary in shell age structure, including both left-skewed (17 out
of 44) and right-skewed distributions (26 out of 44) as well as age distributions with a highly variable kurtosis. Dispersion and
shape of age distributions of samples do not show any notable correlation with the stratigraphic age of samples, suggesting that the
structure and scale of temporal mixing is time invariant. The statistically significant multi-millennial time-averaging observed here
is consistent with previous studies of shell accumulations from various depositional settings and reinforces the importance of dating
numerous specimens per horizon in geochrono logical studies. Unlike in the case of marine samples, typified by right-skewed age
distributions (attributed to an exponential-like shell loss from older age classes), many of the samples analyzed here displayed leftskewed
distributions, suggestive of different dynamics of age mixing in marine versus terrestrial shell accumulations
Buoyancy and Elasticity of Revenue
Revenue, which is essentially obtained through the tax system, is an essential component of development to effectively meet the increasing demand for public services and infrastructure expansion. This paper determines the responsiveness of the implemented tax reforms through the measurement of the buoyancy and elasticity of revenues. Analysis indicates the need for further study on the rate of these measures.revenue, revenue buoyancy, revenue elasticities
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Included, but Deportable: A New Public Health Approach to Policies That Criminalize and Integrate Immigrants.
There has been a burst of research on immigrant health in the United States and an increasing attention to the broad range of state and local policies that are social determinants of immigrant health. Many of these policies criminalize immigrants by regulating the "legality" of their day-to-day lives while others function to integrate immigrants through expanded rights and eligibility for health care, social services, and other resources.Research on the health impact of policies has primarily focused on the extremes of either criminalization or integration. Most immigrants in the United States, however, live in states that possess a combination of both criminalizing and integrating policies, resulting in distinct contexts that may influence their well-being.We present data describing the variations in criminalization and integration policies across states and provide a framework that identifies distinct but concurrent mechanisms of deportability and inclusion that can influence health. Future public health research and practice should address the ongoing dynamics created by both criminalization and integration policies as these likely exacerbate health inequities by citizenship status, race/ethnicity, and other social hierarchies
Vanishing Abelian integrals on zero-dimensional cycles
In this paper we study conditions for the vanishing of Abelian integrals on
families of zero-dimensional cycles. That is, for any rational function ,
characterize all rational functions and zero-sum integers such
that the function vanishes identically. Here
are continuously depending roots of . We introduce a notion of
(un)balanced cycles. Our main result is an inductive solution of the problem of
vanishing of Abelian integrals when are polynomials on a family of
zero-dimensional cycles under the assumption that the family of cycles we
consider is unbalanced as well as all the cycles encountered in the inductive
process. We also solve the problem on some balanced cycles.
The main motivation for our study is the problem of vanishing of Abelian
integrals on single families of one-dimensional cycles. We show that our
problem and our main result are sufficiently rich to include some related
problems, as hyper-elliptic integrals on one-cycles, some applications to
slow-fast planar systems, and the polynomial (and trigonometric) moment problem
for Abel equation. This last problem was recently solved by Pakovich and
Muzychuk (\cite{PM} and \cite{P}). Our approach is largely inspired by their
work, thought we provide examples of vanishing Abelian integrals on zero-cycles
which are not given as a sum of composition terms contrary to the situation in
the solution of the polynomial moment problem.Comment: 35 pages, 1 figure; one reference added; abstract, introduction and
structure change
My Mother\u27s Research/My Daughter\u27s Voice: A Twofold Tale
We write about experiences in the field as mother/researcher/teacher and daughter/student. How was the researcher/teacher influenced by her motherly role? How does a daughter/student experience the displacement of traveling to a new country for her motherâs research? We write simultaneously and present a twofold tale of movement, education, and consciousness
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