Alternative male life histories in Bluegill Sunfish

Male bluegill sunfish are shown to have two alternative mating strategies: cuckoldry or parental care. Cuckolder males first mature at age 2. They follow a developmental sequence of sneaking and then mimicking female behavior to deceptively gain access to spawnings. Males who become parentals (construct nests, attract females, provide brood care) delay maturation until age 7. The parental investment of these males is parasitized by the cuckolders. This system is an example of a truly parasitically dependent mating strategy in vertebrates. A natural selection model is developed to predict the equilibrium frequencies of the two male types. A preliminary test of the model provides qualitative agreement

Extinction by Miscalculation:

Species at Risk Act, Sakinaw sockeye, Cultus sockeye, fisheries management, extinction.

Gauge-invariant tree-level photoproduction amplitudes with form factors

We show how the gauge-invariance formulation given by Haberzettl is implemented in practice for photoproduction amplitudes at the tree level with form factors describing composite nucleons. We demonstrate that, in contrast to Ohta's gauge-invariance prescription, this formalism allows electric current contributions to be multiplied by a form factor, i.e., it does not require that they be treated like bare currents. While different in detail, this nevertheless lends support to previous ad hoc approaches which multiply the Born amplitudes by an overall form factor. Numerical results for kaon photoproduction off the nucleon are given. They show that the gauge procedure by Haberzettl leads to much improved $\chi^2$ values as compared to Ohta's prescription.Comment: 5 pages, RevTeX, two eps figure

Evolutionary consequences of fishing and their implications for salmon

We review the evidence for fisheries-induced evolution in anadromous salmonids. Salmon are exposed to a variety of fishing gears and intensities as immature or maturing individuals. We evaluate the evidence that fishing is causing evolutionary changes to traits including body size, migration timing and age of maturation, and we discuss the implications for fisheries and conservation. Few studies have fully evaluated the ingredients of fisheries-induced evolution: selection intensity, genetic variability, correlation among traits under selection, and response to selection. Most studies are limited in their ability to separate genetic responses from phenotypic plasticity, and environmental change complicates interpretation. However, strong evidence for selection intensity and for genetic variability in salmon fitness traits indicates that fishing can cause detectable evolution within ten or fewer generations. Evolutionary issues are therefore meaningful considerations in salmon fishery management. Evolutionary biologists have rarely been involved in the development of salmon fishing policy, yet evolutionary biology is relevant to the long-term success of fisheries. Future management might consider fishing policy to (i) allow experimental testing of evolutionary responses to exploitation and (ii) improve the long-term sustainability of the fishery by mitigating unfavorable evolutionary responses to fishing. We provide suggestions for how this might be done

Form factors and photoproduction amplitudes

We examine the use of phenomenological form factors in tree level amplitudes for meson photoproduction. Two common recipes are shown to be fundamentally incorrect. An alternate form consistent with gauge invariance and crossing symmetry is proposed.Comment: To be published in PR

Constraints on background contributions from K+ Lambda electroproduction

Results for response functions for kaon electroproduction on the proton are presented. A tree-level hadrodynamical model is adopted and it is shown that some of the electroproduction response functions are particularly powerful with the eye on gaining control over the parameterization of the background diagrams. The existing data set for the p(e,e'K+)Lambda reaction appears to rule out the use of a g_{K+ Lambda p} coupling constant beyond the boundaries of softly broken SU(3) flavor symmetry. Also the use of soft hadronic form factors, which has been proposed as a valid alternative for a hadrodynamical description of the p(gamma,K+)Lambda data in the resonance region, seems to be disfavored by the magnitude of the measured p(e,e'K+)Lambda cross sections.Comment: Accepted for publication in PRC. Includes new data, additional paragraph and figur

Electroexcitation of nucleon resonances

We review recent progress in the investigation of the electroexcitation of nucleon resonances, both in experiment and in theory. The most accurate results have been obtained for the electroexcitation amplitudes of the four lowest excited states, which have been measured in a range of Q2 up to 8 and 4.5 GeV2 for the Delta(1232)P33, N(1535)S11 and N(1440)P11, N(1520)D13}, respectively. These results have been confronted with calculations based on lattice QCD, large-Nc relations, perturbative QCD (pQCD), and QCD-inspired models. The amplitudes for the Delta(1232) indicate large pion-cloud contributions at low Q2 and don't show any sign of approaching the pQCD regime for Q2<7 GeV2. Measured for the first time, the electroexcitation amplitudes of the Roper resonance, N(1440)P11, provide strong evidence for this state as a predominantly radial excitation of a three-quark (3q) ground state, with additional non-3-quark contributions needed to describe the low Q2 behavior of the amplitudes. The longitudinal transition amplitude for the N(1535)S11 was determined and has become a challenge for quark models. Explanations may require large meson-cloud contributions or alternative representations of this state. The N(1520)D13 clearly shows the rapid changeover from helicity-3/2 dominance at the real photon point to helicity-1/2 dominance at Q2 > 0.5 GeV2, confirming a long-standing prediction of the constituent quark model. The interpretation of the moments of resonance transition form factors in terms of transition transverse charge distributions in infinite momentum frame is presented.Comment: 70 pages, 46 figures, will appear in Progress in Particle and Nuclear Physics, v.67, p.1, 201

Kalakasvatusliku taastootmise programm : programm "Riiklikku kaitset vajavate ja ohustatud kalaliikide kaitse ja kalavarude taastootmine (2002-2010)"

TäistekstKäesolev programm on Eesti Vabariigi keskkonnaministri poolt käskkirjaga nr 352, 06.05.2002 kinnitatud juhend kalakasvatusliku taastootmise riikliku poliitika elluviimiseks Eestis, mis käsitleb kõigi praegu või eeldatavasti lähemas tulevikus Eesti veekogudesse asustatavate kalade taastootmise põhimõtteid ja näitab ära kaitset vajavate (ohustatud) kalade taastootmise riikliku finantseerimise prioriteedid ning kalapüügivõimaluste laiendamiseks vajalike kalade asustamiste toetamise prioriteedid. Programmis toodud asustusmahud ja kohad on soovituslikud ja lähtuvad 2001. aastal prognoositud reaalsetest võimalustest.Taustanalüüs. Kalavarud on tähtis taastuv loodusvara, mille kasutamine peab olema kooskõlas nii rahvusvaheliselt kui Eestis heaks kiidetud säästva arengu põhimõtetega. Eesti säästva arengu seadus sätestab, et loodusvarade säästva kasutamise eesmärgiks on tagada inimest rahuldav elukeskkond ja majanduse arenguks vajalikud ressursid elukeskkonda oluliselt kahjustamata ning looduslikku mitmekesisust säilitades. Kalade arvukuse säilitamise või suurendamise põhimõttelised võimalused on: 1) püügi reguleerimine kalapüügieeskirjas määratud piirangutega (keeluajad ja -piirkonnad, lubatud püünised ja alammõõt jne) ja püüniste arvu või kalakoguse limiteerimisega; 2) elukeskkonna (eeskätt sigimisvõimaluste) kaitse, parandamine või taastamine; 3) kalakasvatuslik taastootmine (kalakasvandustes üleskasvatatud noorkalade asustamine veekogudesse, edaspidi lühendatult taastootmine). Viimane on kulukas tegevus, mis eeldab pikaajalist planeerimist ja otstarbekuse analüüsi. Kalade kaitsemeetmed on sätestatud mitmetes õigusaktides ja dokumentides. Loodusliku mitmekesisuse kaitse huvides on Eestis vastu võetud mitmeid programme, mis puudutavad ka kalu. Igakülgsete kaitsemeetmete väljatöötamine jätkub seoses Eesti ja Euroopa Liidu keskkonnakaitse poliitika harmoniseerimisega. Tehistingimustes peetud loomade loodusesse laskmine (seega ka kalade asustamine kalakasvandustest) toimub loomastiku kaitse ja kasutamise seaduse § 19 järgi keskkonnaministri poolt kinnitatud programmi alusel. Käesolevas programmis on koondatud tähelepanu ohustatud ja majanduslikult kasutatavate kalaliikide arvukuse suurendamisele kalakasvatusliku taastootmise kaudu. Eesti 74 kalaliigist (Saat, 1992) on 8 inimtegevusest ohustatud (neist 4 on looduskaitse all), veel 4 liigi arvukus oleneb tugevasti inimtegevusest. Osa ohustatud liikidest on samal ajal kalanduslikult tähtsad ja neid püütakse pidevalt. Eestis on ka 7 liiki Euroopa Liidus (EL loodusdirektiivi alusel) ohustatuks loetud ja kaitstavaid kalu (sh kolm sõõrsuuliiki), mis on meil kas harva esinevad eksikülalised või pole siin otseselt ohustatud. Kalavarude suurendamiseks ja püügivõimaluste loomiseks taastoodetakse või on toodetud 5 mitteohustatud liiki. Majanduslikult kasutatavate veeorganismide hulka kuulub peale kalade ka inimtegevusest ohustatud jõevähk, mistõttu sellekohaseid probleeme käsitletakse käesolevas dokumendis koos kaladega. Sellise mitmekesisuse tõttu tuleb vaadelda Eestis riiklikku kaitset ja taastootmist vajavaid kalaliike rühmadena, mille suhtes rakendatavad meetmed ja riikliku toetamise vajadus on erinevad. Forelli ja siia liigisiseseid vorme käsitletakse nende ökoloogia erinevuste tõttu eraldi

Conclusions of the II International and IV Spanish Hydration Congress. Toledo, Spain, 2nd-4th December, 2015

Water is the major component of our organism representing about 60% of total body weight in adults and has to be obtained through the consumption of different foods and beverages as part of our diet. Water is an essential nutrient performing important functions, including transport of other nutrients, elimination of waste products, temperature regulation, lubrication and structural support. In this context, hydration through water has an essential role in health and wellness, which has been highly acknowledged in recent years among the health community experts such as nutritionists, dietitians, general practitioners, pharmacists, educators, as well as by physical activity and sport sciences experts and the general population

Global Assessment of Extinction Risk to Populations of Sockeye Salmon Oncorhynchus nerka

BACKGROUND: Concern about the decline of wild salmon has attracted the attention of the International Union for the Conservation of Nature (IUCN). The IUCN applies quantitative criteria to assess risk of extinction and publishes its results on the Red List of Threatened Species. However, the focus is on the species level and thus may fail to show the risk to populations. The IUCN has adapted their criteria to apply to populations but there exist few examples of this type of assessment. We assessed the status of sockeye salmon Oncorhynchus nerka as a model for application of the IUCN population-level assessments and to provide the first global assessment of the status of an anadromous Pacific salmon. METHODS/PRINCIPAL FINDINGS: We found from demographic data that the sockeye salmon species is not presently at risk of extinction. We identified 98 independent populations with varying levels of risk within the species' range. Of these, 5 (5%) are already extinct. We analyzed the risk for 62 out of 93 extant populations (67%) and found that 17 of these (27%) are at risk of extinction. The greatest number and concentration of extinct and threatened populations is in the southern part of the North American range, primarily due to overfishing, freshwater habitat loss, dams, hatcheries, and changing ocean conditions. CONCLUSIONS/SIGNIFICANCE: Although sockeye salmon are not at risk at the species-level, about one-third of the populations that we analyzed are at risk or already extinct. Without an understanding of risk to biodiversity at the level of populations, the biodiversity loss in salmon would be greatly underrepresented on the Red List. We urge government, conservation organizations, scientists and the public to recognize this limitation of the Red List. We also urge recognition that about one-third of sockeye salmon global population diversity is at risk of extinction or already extinct