Comparison of Pond Production of Phase-III Sunshine Bass Fed 32-, 36-, and 40%-Crude-Protein Diets with Fixed Energy : Protein Ratios

We stocked phase-III sunshine bass (white bass Morone chrysops ♀ × striped bass M. saxatilis ♂) at a rate of 6,188 fingerlings/ha into twelve 0.04-ha earthen ponds supplied with continuous aeration. Three dietary treatments were randomly assigned to quadruplicate ponds. Sunshine bass were fed to apparent satiation once daily after average initial weight (mean ± SE = 214 ± 5 g) and total length (245 ± 1.6 mm) were determined. Diets were formulated to conserve the estimated digestible energy:crude protein (CP) ratio (9.3 kcal/g protein) and represented the following CP and energy values fed to fish: 32% CP (3,000 kcal/kg), 36% CP (3,360 kcal/kg), and 40% CP (3,760 kcal/kg). Harvest data suggest that nutrient density is a variable that can be manipulated to optimize production and reduce production costs. Production rates (mean ± SE) were 2,851 ± 600 kg/ha for the 32%-CP diet, 2,895 ± 341 kg/ha for the 36%-CP diet, and 2,953 ± 142 kg/ha for the 40%-CP diet; production rates were not significantly different among dietary treatments. Survival was excellent and did not appear to be related to dietary treatment. Dressed (gilled and gutted) fish averaged 80% of whole-fish weight, and the dressed percentage did not vary as a function of nutrient density. Feed conversion ratios of 3.0 ± 0.4, 2.8 ± 0.2, and 2.6 ± 0.1 were obtained for the fish fed 32-, 36-, and 40%-CP diets, respectively. Protein conversion ratios (mean = 1.0) were not significantly influenced by dietary treatment. Feed cost increased with increasing dietary CP level; costs were US$0.447 per kilogram for the 32$0.493 per kilogram for the 36%-CP diet, and $0.541 per kilogram for the 40$1.34, $1.38, and$1.41 per kilogram of gain for the 32-, 36-, and 40%-CP diets, respectively. A savings of $0.16 per kilogram produced, or approximately$450 per hectare, was realized as a result of feeding either of the two lower-CP, lower-energy diets. Accordingly, we suggest that phase-III sunshine bass can be more economically produced by feeding diets as low as 32% CP with a minimum energy:protein ratio of 9.3 kcal/g CP

The 1991 WMO ozone sonde intercomparison

The WMO ozone sonde intercomparison was held at Vanscoy, Saskatchewan from May 13 to May 24, 1991. The purpose of the intercomparison is to evaluate the performance of various ozone sonde types used operationally in the Global Ozone Observing System and to ensure that the accuracy and precision of the measurements are sufficient to detect long-term trends in stratospheric ozone. The intercomparison was sponsored by WMO and hosted by the Atmospheric Environment Service (AES) of Canada. It was attended by scientists from six countries: Canada, Finland, Germany, India, Japan and USA. A total of 10 balloon payloads were launched each carrying 7 or 8 sondes for a total of 67 successful ozone sonde flights. The payloads were carried to altitudes between 35 and 40 km where the flights terminated by balloon burst. Results of the profile measurements made during the series of the profile measurements made during the series of flight are used to determine statistically meaningful evaluations of the different sonde types. A description of the payload and the different ozone sondes is given. Preliminary results of the profile measurements and an evaluation of the performance of the sonde types are presented

Environmental and Organismal Predictors of Intraspecific Variation in the Stoichiometry of a Neotropical Freshwater Fish

The elemental composition of animals, or their organismal stoichiometry, is thought to constrain their contribution to nutrient recycling, their interactions with other animals, and their demographic rates. Factors that affect organismal stoichiometry are generally poorly understood, but likely reflect elemental investments in morphological features and life history traits, acting in concert with the environmental availability of elements. We assessed the relative contribution of organismal traits and environmental variability to the stoichiometry of an insectivorous Neotropical stream fish, Rivulus hartii. We characterized the influence of body size, life history phenotype, stage of maturity, and environmental variability on organismal stoichiometry in 6 streams that differ in a broad suite of environmental variables. The elemental composition of R. hartii was variable, and overlapped with the wide range of elemental composition documented across freshwater fish taxa. Average %P composition was ∼3.2%(±0.6), average %N∼10.7%(±0.9), and average %C∼41.7%(±3.1). Streams were the strongest predictor of organismal stoichiometry, and explained up to 18% of the overall variance. This effect appeared to be largely explained by variability in quality of basal resources such as epilithon N∶P and benthic organic matter C∶N, along with variability in invertebrate standing stocks, an important food source for R. hartii. Organismal traits were weak predictors of organismal stoichiometry in this species, explaining when combined up to 7% of the overall variance in stoichiometry. Body size was significantly and positively correlated with %P, and negatively with N∶P, and C∶P, and life history phenotype was significantly correlated with %C, %P, C∶P and C∶N. Our study suggests that spatial variability in elemental availability is more strongly correlated with organismal stoichiometry than organismal traits, and suggests that the stoichiometry of carnivores may not be completely buffered from environmental variability. We discuss the relevance of these findings to ecological stoichiometry theory

Live SIV vaccine correlate of protection: immune complex-inhibitory Fc receptor interactions that reduce target cell availability

Principles to guide design of an effective vaccine against HIV are greatly needed, particularly to protect women in the pandemic’s epicentre in Africa. We have been seeking these principles by identifying correlates of the robust protection associated with SIVmac239Δnef vaccination in the SIV-rhesus macaque animal model of HIV-1 transmission to women. We have identified one correlate of SIVmac239Δnef protection against vaginal challenge as a resident mucosal system for SIV-gp41 trimer antibody production and neonatal Fc receptor (FcRn)-mediated concentration of these antibodies on the path of virus entry to inhibit establishment of infected founder populations at the portal of entry. Here we identify as a second protection correlate, blocking CD4+ T cell recruitment to inhibit local expansion of infected founder populations. Virus-specific immune complex interactions with the inhibitory FcγRIIb receptor in the epithelium lining the cervix initiate expression of genes that block recruitment of target cells to fuel local expansion. Immune complex-FcγRIIb receptor interactions at mucosal frontlines to dampen the innate immune response to vaginal challenge could be a potentially general mechanism for the mucosal immune system to sense and modulate the response to a previously encountered pathogen. Designing vaccines to provide protection without eliciting these transmission-promoting innate responses could contribute to developing an effective HIV-1 vaccine

Live SIV vaccine correlate of protection: immune complex-inhibitory Fc receptor interactions that reduce target cell availability

Principles to guide design of an effective vaccine against HIV are greatly needed, particularly to protect women in the pandemic’s epicentre in Africa. We have been seeking these principles by identifying correlates of the robust protection associated with SIVmac239Δnef vaccination in the SIV-rhesus macaque animal model of HIV-1 transmission to women. We have identified one correlate of SIVmac239Δnef protection against vaginal challenge as a resident mucosal system for SIV-gp41 trimer antibody production and neonatal Fc receptor (FcRn)-mediated concentration of these antibodies on the path of virus entry to inhibit establishment of infected founder populations at the portal of entry. Here we identify as a second protection correlate, blocking CD4+ T cell recruitment to inhibit local expansion of infected founder populations. Virus-specific immune complex interactions with the inhibitory FcγRIIb receptor in the epithelium lining the cervix initiate expression of genes that block recruitment of target cells to fuel local expansion. Immune complex-FcγRIIb receptor interactions at mucosal frontlines to dampen the innate immune response to vaginal challenge could be a potentially general mechanism for the mucosal immune system to sense and modulate the response to a previously encountered pathogen. Designing vaccines to provide protection without eliciting these transmission-promoting innate responses could contribute to developing an effective HIV-1 vaccine

Globalization, Roundaboutness, and Relative Wages

We depart from the trade and wages literature and its emphasis on North-South trade, examining North-North by developing the basic linkages between trade-based integration and relative wages in an Ethier-type division of labor model. Using this model we identify a formal relationship between international trade, productivity, and wages. We then examine the trivariate relationship between trade, growth in total factor productivity (TFP), and the skill premium in a vector autoregression framework. We find evidence of a long-run relationship between growth in intermediate goods and changes in TFP. Controlling for this relationship we also find a positive relationship between trade and the skill-premium

Images of Crust Beneath Southern California Will Aid Study of Earthquakes and Their Effects

The Whittier Narrows earthquake of 1987 and the Northridge earthquake of 1991 highlighted the earthquake hazards associated with buried faults in the Los Angeles region. A more thorough knowledge of the subsurface structure of southern California is needed to reveal these and other buried faults and to aid us in understanding how the earthquake-producing machinery works in this region

The Spitzer c2d Survey of Weak-Line T Tauri Stars. III. The Transition from Primordial Disks to Debris Disks

We present 3.6 to 70 {\mu}m Spitzer photometry of 154 weak-line T Tauri stars (WTTS) in the Chamaeleon, Lupus, Ophiuchus and Taurus star formation regions, all of which are within 200 pc of the Sun. For a comparative study, we also include 33 classical T Tauri stars (CTTS) which are located in the same star forming regions. Spitzer sensitivities allow us to robustly detect the photosphere in the IRAC bands (3.6 to 8 {\mu}m) and the 24 {\mu}m MIPS band. In the 70 {\mu}m MIPS band, we are able to detect dust emission brighter than roughly 40 times the photosphere. These observations represent the most sensitive WTTS survey in the mid to far infrared to date, and reveal the frequency of outer disks (r = 3-50 AU) around WTTS. The 70 {\mu}m photometry for half the c2d WTTS sample (the on-cloud objects), which were not included in the earlier papers in this series, Padgett et al. (2006) and Cieza et al. (2007), are presented here for the first time. We find a disk frequency of 19% for on-cloud WTTS, but just 5% for off- cloud WTTS, similar to the value reported in the earlier works. WTTS exhibit spectral energy distributions (SEDs) that are quite diverse, spanning the range from optically thick to optically thin disks. Most disks become more tenuous than Ldisk/L* = 2 x 10^-3 in 2 Myr, and more tenuous than Ldisk/L* = 5 x 10^-4 in 4 Myr.Comment: 40 pages, 13 figures, 4 tables. Accepted for publication in ApJ on September 20, 201

Meeting reports: Research on Coupled Human and Natural Systems (CHANS): Approach, Challenges, and Strategies

Understanding the complexity of human–nature interactions is central to the quest for both human well-being and global sustainability. To build an understanding of these interactions, scientists, planners, resource managers, policymakers, and communities increasingly are collaborating across wide-ranging disciplines and knowledge domains. Scientists and others are generating new integrated knowledge on top of their requisite specialized knowledge to understand complex systems in order to solve pressing environmental and social problems (e.g., Carpenter et al. 2009). One approach to this sort of integration, bringing together detailed knowledge of various disciplines (e.g., social, economic, biological, and geophysical), has become known as the study of Coupled Human and Natural Systems, or CHANS (Liu et al. 2007a, b). In 2007 a formal standing program in Dynamics of Coupled Natural and Human Systems was created by the U.S. National Science Foundation. Recently, the program supported the launch of an International Network of Research on Coupled Human and Natural Systems (CHANS-Net.org). A major kick-off event of the network was a symposium on Complexity in Human–Nature Interactions across Landscapes, which brought together leading CHANS scientists at the 2009 meeting of the U.S. Regional Association of the International Association for Landscape Ecology in Snowbird, Utah. The symposium highlighted original and innovative research emphasizing reciprocal interactions between human and natural systems at multiple spatial, temporal, and organizational scales. The presentations can be found at ‹http://chans- net.org/Symposium_2009.aspx›. The symposium was accompanied by a workshop on Challenges and Opportunities in CHANS Research. This article provides an overview of the CHANS approach, outlines the primary challenges facing the CHANS research community, and discusses potential strategies to meet these challenges, based upon the presentations and discussions among participants at the Snowbird meeting

Dietary fibre intake and risk of ischaemic and haemorrhagic stroke in the UK Women’s Cohort Study

BACKGROUND: Stroke risk is modifiable through many risk factors, one being healthy dietary habits. Fibre intake was associated with a reduced stroke risk in recent meta-analyses; however, data were contributed by relatively few studies, and few examined different stroke types. METHODS: A total of 27 373 disease-free women were followed up for 14.4 years. Diet was assessed with a 217-item food frequency questionnaire and stroke cases were identified using English Hospital Episode Statistics and mortality records. Survival analysis was applied to assess the risk of total, ischaemic or haemorrhagic stroke in relation to fibre intake. RESULTS: A total of 135 haemorrhagic and 184 ischaemic stroke cases were identified in addition to 138 cases where the stroke type was unknown or not recorded. Greater intake of total fibre, higher fibre density and greater soluble fibre, insoluble fibre and fibre from cereals were associated with a significantly lower risk for total stroke. For total stroke, the hazard ratio per 6 g/day total fibre intake was 0.89 (95% confidence intervals: 0.81–0.99). Different findings were observed for haemorrhagic and ischaemic stroke in healthy-weight or overweight women. Total fibre, insoluble fibre and cereal fibre were inversely associated with haemorrhagic stroke risk in overweight/obese participants, and in healthy-weight women greater cereal fibre was associated with a lower ischaemic stroke risk. In non-hypertensive women, higher fibre density was associated with lower ischaemic stroke risk. CONCLUSIONS: Greater total fibre and fibre from cereals are associated with a lower stroke risk, and associations were more consistent with ischaemic stroke. The different observations by stroke type, body mass index group or hypertensive status indicates potentially different mechanisms