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Krill are shrimp-like crustaceans with a high degree of mobility and variety of documented swimming behaviors. The caridoid escape response, a fast-start mechanism unique to crustaceans, occurs when the animal performs a series of rapid abdominal flexions and tail flipping that results in powerful backward strokes. The current results quantify the animal kinematics and three-dimensional flow field around a free-swimming Euphausia superba as it performs the caridoid escape maneuver. The specimen performs a single abdominal flexion-tail flip combination that leads to an acceleration over a 42 ms interval allowing it to reach a maximum speed of 57.0 cm/s (17.3 body lengths/s). The krill’s tail flipping during the abdominal closure is a significant contributor to the thrust generation during the maneuver. The krill sheds a complex chain of vortex rings in its wake due to the viscous flow effects while the organism accelerates. The vortex ring structure reveals a strong suction flow in the wake, which suggests that the pressure distribution and form drag play a role in the force balance for this maneuver. Antarctic krill typically swim in a low to intermediate Reynolds number (Re) regime where viscous forces are significant, but as shown by this analysis, its high maneuverability allows it to quickly change its body angle and swimming speed.

This paper evaluates industry-wide economic incentives arising from changes in product prices in an industry exploiting a common renewable resource (tropical tunas) that is regulated via output limits. Changes in prices alter economic incentives by affecting revenues, profits, conservation, and nonmarket public benefits. Economic incentives in industries exploiting common resources have been examined from multiple angles. However, industry level variation in market prices arising from changes in public regulation has not been explored. We analyse the impact on economic incentives due to changes in output limits and market prices through estimation of ex-vessel price and scale flexibilities for imported skipjack and yellowfin in Thailand’s cannery market. The unitary scale flexibility, estimated from the General Synthetic Inverse Demand Systems, indicates no loss in revenue and even potential profit increases resulting from lower harvest levels that could arise from lower catch limits. However, for a revenue neutral or positive outcome to be achieved, the three inter-governmental tuna Regional Fisheries Management Organizations, which manage the majority of the yellowfin and skipjack tuna in the Pacific and Indian Oceans, would have to coordinate multilaterally to set the catch limits for both species.

Single-stock management dominates the international regulation of marine fisheries. Indeed, the maximum sustainable yield (MSY) rubric is used in 10 of 16 marine regional fisheries management organizations (RFMOs). Early on, MSY was the best, and often only, scientific benchmark available. Now, scientists know much more about ecosystem interactions and have the tools to implement multi-species management, but RFMOs continue to manage stocks and species separately. This article explores the reasons for this continuity and the potential for change in the system. In it, I propose that a focus on allocation rather than conservation generates preferences for MSY over the lower, more precautionary, catch limits that would result from an ecosystem approach. I test this hypothesis using RFMO data. I then move on to discuss the results and propose that strategic considerations should be taken into account when advocating for ecosystem-based management.

Climate change could substantially alter the width of beaches in Southern California. Climate-driven sea level rise will have at least two important impacts on beaches: (1) higher sea level will cause all beaches to become more narrow, all things being held constant, and (2) sea level rise may affect patterns of beach erosion and accretion when severe storms combine with higher high tides. To understand the potential economic impacts of these two outcomes, this study examined the physical and economic effects of permanent beach loss caused by inundation due to sea level rise of one meter and of erosion and accretion caused by a single, extremely stormy year (using a model of beach change based on the wave climate conditions of the El Nino year of 1982/1983.) We use a random utility model of beach attendance in Southern California that estimates the impacts of changes on beach width for different types of beach user visiting public beaches in Los Angeles and Orange Counties. The model allows beachgoers to have different preferences for beach width change depending on beach size. We find that the effect of climate-driven beach change differs for users that participate in bike path activities, sand-based activities, and water-based activities. We simulate the effects of climate-related beach loss on attendance patterns at 51 public beaches, beach-related expenditures at those beaches, and the non-market (consumer surplus) value of beach going to those beaches. We estimate that increasing sea level will cause an overall reduction of economic value in beach going, with some beaches experiencing increasing attendance and beach-related earnings while attendance and earnings at other beaches would be lower. We also estimate that the potential annual economic impacts from a single stormy year may be as large as those caused by permanent inundation that would result from a rise in sea level of one meter. The economic impacts of both permanent inundation and storm-related erosion are distributed unevenly across the region. To put the economic impacts of these changes in beach width in perspective, the paper provides simple estimates of the cost of mitigating beach loss by nourishing beaches with sand.

The functional interaction of BAFF and APRIL with TNF receptor superfamily members BAFFR, TACI and BCMA is crucial for development and maintenance of humoral immunity in mice and humans. Using a candidate gene approach, we identified homozygous and heterozygous mutations in TNFRSF13B, encoding TACI, in 13 individuals with common variable immunodeficiency. Homozygosity with respect to mutations causing the amino acid substitutions S144X and C104R abrogated APRIL binding and resulted in loss of TACI function, as evidenced by impaired proliferative response to IgM-APRIL costimulation and defective class switch recombination induced by IL-10 and APRIL or BAFF. Family members heterozygous with respect to the C104R mutation and individuals with sporadic common variable immunodeficiency who were heterozygous with respect to the amino acid substitutions A181E, S194X and R202H had humoral immunodeficiency. Although signs of autoimmunity and lymphoproliferation are evident, the human phenotype differs from that of the Tnfrsf13b-/- mouse model.

A common-rail diesel vehicle was equipped with a full-scale Ag/alumina catalytic converter. The converter consisted of several Ag/alumina bricks, with free space in between each brick to fulfil important gas phase reactions. An oxidation catalyst was placed at the end of the converter to remove formed CO and unburned HC. High conversion levels of NOx, around 60%, were recorded at several speeds and loads using additional HC (diesel) injection corresponding to 2–5% fuel penalty.

We present a dense STR/linkage disequilibrium(LD)/gene map between the RING3 and HLA-B loci, reference allelic sizes on the most prevalent HLA haplotypes and their allelic frequencies in pedigree founders. This resource will facilitate LD, evolution and gene mapping studies, including comparisons of HLA and STR haplotypes and identification of HLA recombinants. The map was constructed by testing novel and previously reported STRs using a panel of 885 individuals in 211 families and 60 DNA samples from cell lines and bone marrow donors homozygous in the HLA-A, -B and -DR loci selected from over 15 000 entries into the registry of Swedish bone marrow donors. We have also analysed the variability of STR alleles/haplotypes on the most prevalent HLA haplotypes to identify STRs useful for fine mapping of disease genes in the region previously implicated in susceptibility to many disorders. The analysis of 40 HLA-A*01, B*0801, DRB1*03011, DQB1*0201 haplotypes in homozygous donors showed a surprising stability in 23 STRs between the class II recombination hot spot and HLA-B, with the average of 1.9% (16/838) variant alleles. However, 40% variant alleles were found at the D6S2670 locus in intron 19 of the tenascin-X gene both in the families and homozygous donors. The nucleotide sequence analysis of this STR showed a complex polymorphism consisting of tetra- (CTTT)(8-18) and penta-nucleotide (CTTTT)(1-2) repeats, separated by an intervening non-polymorphic sequence of 42 bp. The HLA-A1, B*0801, DRB1*03011, DQB1*0201 haplotypes had five (CTTT)(14-18)/(CTTTT)(2) variants with a predominant (CTTT)(16) allele, implicating the tetranucleotide component as the source of this ancestral haplotype diversification, which may be due to the location of D6S2670 in the region of the highest GC content in the human MHC.

The six papers presented here all point out the grave difficulties associated with the management of international fisheries. Each also provides some perspective on the potential for change in the system. Webster recommends that proponents of ecosystem-based management need to propose specific measures that may appeal to powerful fishing countries rather than broad goals that are difficult to implement. Kalfagianni and Pattberg propose that the Marine Stewardship Council could substantially improve its impact on global fisheries management by paying attention to structural effects, particularly trade barriers that may exacerbate the North–South divide. Sakaguchi similarly sees NGO involvement in fisheries regulation as a double-edged sword and warns about the potential for alienation of societies that resist the forceful imposition of new norms. In contrast, both Schiffman and Tiller show how domestic interests can shape new and future regional fisheries management organisations (RFMOs) into more effective regimes. Finally, Barkin and DeSombre propose that a new, global RFMO could reduce fishing capacity around the world, thereby bursting the balloon problem.

Au cours des dernieres annees, la methode goniometrique permettant de trouver les directions d’arrivee a ete appliquee aux sources de sifflements de tres basse frequence. Nous avons adapte cette technique de facon a pouvoir l’utiliser dans la bandeUbf.On se sert de deux bobines croisees et l’on synthetise par des methodes electroniques, un signal equivalent a une bobine tournante. La methode est utilisee pour determiner l’azimut de la source des pulsations geomagnetiques de type pc 1 se propageant dans le guide de la region F 2 depuis les latitudes elevees jusqu’aux latitudes moyennes. Les donnees enregistrees sont numerisees par un mini ordinateur et les analyses par transformee de Fourier rapide et par correlation sont faites pour calculer les azimuts. On discute quelques aspects de la methode goniometrique, particulierement importants pour l’etude des pc 1, ainsi que les techniques d’analyse de donnees.

The results of a systematic study of helium thin-film adsorption are presented. Measurements are reported, obtained with a 24-MHz crystal adsorptometer, on the adsorbed mass per unit area as a function of the three independent variables temperature, concentration, and pressure of the gas of 3He-4He atoms generating the adsorbed film. The investigations span concentrations from zero to unity, all pressures up to the dew point for each mixture, and temperatures from 1.3 to 2.1 K. From the experimental results we display the detailed form of the van der Waals attractive potential holding the helium atoms to the surface. The expected dependence on the cube of the distance from the substrate is confirmed over the range of distances explored. The strength of the van der Waals potential is measured and reported. This attractive potential is demonstrated to be of the same form and of the same strength both for the 3He atoms and for the 4He atoms in the mixture at all concentrations. We further deduce, directly from our measurements, the detailed relationship between Σ, the mass per unit area of film absorbed, and d, the thickness of the film.

An immunological profile has been serially studied in 72 patients with advanced breast cancer during the course of a randomized trial of chemotherapy and hormonal manipulation. DNCB+ patients were more likely to respond to either therapy, but no other test was predictive of response. In the follow-up period all chemotherapy patients had a reduction in white-cell count which was significantly greater in those responding to treatment. None of the other tests (phytohaemagglutinin response, immunoglobulins G, A and M, or Mantoux test) demonstrated changes that could be related to treatment or response, but there was a gradual unexplained fall in IgM levels in all groups the study progressed. It is concluded that the chemotherapeutic regimen (cyclophosphamide, vincristine, adriamycin and 5-fluorouracil) is relatively non-immunosuppressive, and that hormonal therapy (oophorectomy, tamoxifen or androgens) had no detectable effect on the immune response.

(1) The fact that there are two phases in the action of fat on gastric secretion, when fat is administered in conjunction with other stimulants—aninhibitory and anexcitatory phase—was confirmed in differently operated dogs.

Introduction into the duodenum of 0.25 per cent hydrochloric acid or of gastric juice, diluted two to four times, inhibits the gastric secretion stimulated(a) through the parasympathetic nervous system or(b) by the presence in the intestine of food substances or the products of their digestion. The same effect was produced by the gastric glands. The theory is advanced that the passage of the acid chyme from the stomach into the duodenum causes the gastric secretion to diminish, this being an important factor in regulating the activity of the gastric glands.

Vitreoscilla, a filamentous bacterium in the Beggiatoa family, synthesizes a soluble haem-protein which has two identical subunits of relative molecular mass 15,775 and two b haems per molecule. It is synthesized in relatively large quantities when the organism, a strict aerobe, is grown under hypoxic conditions. It forms a relatively stable oxygenated form which is spectrally similar to oxymyoglobin (oxyHb) and oxyhaemoglobin (oxyHb). The amino acid sequence of this protein has been determined and aligned to fit the helical regions of several animal and plant globins. This alignment is consistent with its being a structural homologue of the eucaryotic haemoglobins although it diverged from the others in the N-terminal region and may lack an A-helix. It showed the maximum sequence homology (24%) with lupin leghaemoglobin (Lb). Vitreoscilla Hb is the first bacterial haemoglobin to be sequenced. It may function to enable the organism to survive in oxygen-limited environments by acting as an oxygen storage-trap or to facilitate oxygen diffusion.

A key-pecking response in pigeons was shaped and maintained by intracranial stimulation as the sole reinforcer, using current levels of stimulation up to 500 microA. Orderly functions relating response rate to stimulation intensity were obtained. High local rates of pecking were obtained at all intensities of stimulation, but rests from pecking were longer at lower intensities.

THE tendency in many species to confuse pairs of stimuli which are lateral mirror images of one another1 may survive attempts to train animals to discriminate between mirror images. Even when such training has apparently been successful, the animal may actually distinguish the stimuli on the basis of cues other than left–right ones2.