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Fishes caught from depth often suffer from barotrauma, which can result in high mortality rates (close to 100% for some species) when released at the surface. To mitigate for this, the recreational fishing community pro-actively developed several different types of descending devices designed to assist unwanted or prohibited fish back toward the bottom for release. Post-release survival using recompression techniques has been documented for some species, which has allowed fisheries managers to begin revising estimates of total fishing mortality in some cases, but the effectiveness of the different commercially-available descending device types has not been quantified. We conducted 24 Commercial Passenger Fishing Vessel charters at 11 sites along the coast of California, and invited volunteer recreational anglers aboard the charters to test the effectiveness of five different commercially available device types, and respond to a survey of their device preferences. During release, all fish were descended either to 46 m (150 ft) depth or directly to the bottom, whichever depth was shallower. While there were some significant differences between device types, all devices were effective for releasing rockfishes back to depth. Initial post-release mortality (defined as all mortality events observable from the vessel while fishing) across all devices was relatively low (7.5%) in capture depths less than 100 m, but increased significantly to 16.4% at capture depths from 100 to 135 m. Our results suggest that rockfishes should be released at least half-way to the bottom (preferably directly to the bottom) for the device to be effective in minimizing post-release mortality. The time required to use the devices averaged under three minutes regardless of device type, meaning that all device types could be used efficiently on deck, but anglers showed a clear preference for the SeaQualizer™. This device produced some of the lowest release error rates and lowest initial post-release mortality of rockfishes aboard the charters, so angler preference coincided with device effectiveness. Collaborating with the recreational fishing community was an extremely important aspect to this study, provided more robust results, and fostered working relationships that can be built upon in future research projects.

An understanding of the reproductive biology of a species is fundamental to successful management of fish stocks. Rockfish (Sebastes spp.) have complex reproduction, being viviparous and generally late to mature, often with extended adolescent periods characterized by abortive maturation events. Furthermore, whereas the majority of Sebastes species in the California Current region produce one brood of larvae annually, several are known to produce more than one, though no stock assessments have yet considered the impact multiple brooding may have on population spawning potential for these species. We documented abortive maturation and examined the prevalence and size-dependent and regional patterns of multiple brooding using macroscopic evaluation and detailed histological analysis of ovaries from a model species, chilipepper (S. goodei), collected off Central and Southern California. We modeled the size-related maternal effect on the probability of multiple brooding, and quantified size-dependent fecundity relationships. Our results indicate that the most robust estimation of reproductive output, as a function of the fecundity-length relationship, is improved for chilipepper when multiple brooding is incorporated, due to the greater probability of additional broods, and thus greater spawning potential, in larger females.

Estimates of fecundity at size are a key component of age-structured population dynamics models such as those used for stock assessment purposes. Fecundity-length relationships for many exploited fish stocks are often poorly understood due to small sample sizes and high levels of intrinsic variability among individuals. Several species in the genus Sebastes match this description, and are important components of commercial and recreational fisheries off the U.S. West Coast. We used a hierarchical Bayesian modeling framework for simultaneous estimation of parameters in the fecundity-length relationships for 29 species of rockfish while accounting for variability within and among subgenera. Hierarchical models that account for subgeneric phylogenetic structure and variability among species outperformed models that treat all species in the genus as exchangeable or ignored variation among species within a subgenus, based on a predictive information criterion. Our results confirm that weight-specific fecundity increases with size in nearly all Sebastes species, and that the assumption of proportionality between mature female biomass and total egg production is inappropriate for most Sebastes stock assessments. Benefits of the hierarchical framework include prediction of fecundity-length parameters at the genus, subgenus, and species level, as well as predictive distributions for unobserved Sebastes species.

a b s t r a c t A comprehensive understanding of reproductive biology is fundamental to the accurate assessment of a given stock's spawning potential relative to the unfished level. Such an understanding is particularly important given the growing recognition of size, age or weight dependent relative fecundity (Фrel, eggs per kg of female weight), or other maternal effects that may demonstrate a relatively greater contribu- tion of specific demographic components of a population toward reproduction. However, size-specific data on Фrel, or other data on maternal effects on reproductive output, are not always available for many stock assessments because intensive efforts are required to collect such data. In the absence of data, the assumption of no size-specific Фrel relationship is typically made, which can lead to bias in esti- mating stock status and related management parameters. We examined effects of misspecifications of size-specific Фrel functions on estimated stock assessment parameters and related management quan- tities using two stocks as case studies and three sets of simulation models, chosen to represent wide ranges of life and fishing histories. The results showed that misspecification effects were relatively small when stocks were less depleted (e.g. 75% of virgin spawning output), but could lead to more substantive misspecifications in more depleted stocks with slower growth and lower mortality rates. For example, we found that stock was estimated to be as much as 20% less depleted if a strong size-specific Фrel exists in a population, but no size-specific Фrel is used in the model. This represents a non-trivial shift in the perception of status for most stocks. The results also showed that overestimating the strength of the size-specific Фrel function in stock assessment models led to smaller estimation errors in assessment outputs compared to underestimating the size-specific Фrel. The results are insightful with respect to the importance of gathering data on size-dependent Фrel and other aspects of reproductive ecology, as well as with respect to the nature of assumptions that are made with regards to reproductive ecology in data limited situations. Published by Elsevier B.V.

This paper describes the algorithm's engineering of a covariance matrix self-adaptation evolution strategy (CMSA-ES) for solving a mixed linear/nonlinear constrained optimization problem arising in portfolio optimization. While the feasible solution space is defined by the (probabilistic) simplex, the nonlinearity comes in by a cardinality constraint bounding the number of linear inequalities violated. This gives rise to a nonconvex optimization problem. The design is based on the CMSA-ES and relies on three specific techniques to fulfill the different constraints. The resulting algorithm is then thoroughly tested on a data set derived from time series data of the Dow Jones Index.

This work discusses a method for measuring k-values of low-k films after integration in damascene structures. The experimental results are obtained from 90nm 1/2 pitch single damascene structures on low-k materials with intrinsic k-values ranging between 2.2 and 3. The measurement technique is discussed in detail with a focus on the accuracy, limitation of the method, impact of low-k damage and applicability for smaller dimensions.

Chilipepper rockfish ( Sebastes goodei ), a long-lived, highly fecund commercial species in the California Current ecosystem, contend with a variable environment on several time scales. Using a bioenergetics model, we simulated alternate strategies of energy allocation by female chilipeppers under variable conditions, and examined resulting patterns in age-dependent size and fecundity. Variable conditions consisted of single climate events (one anomalous year, one 4-year regime shift, or one 10-year regime shift) that occurred at different points over the lifespan of the fish and were either “poor” or “good” relative to baseline conditions. Poor years or regimes reduced growth and fecundity, while good years or regimes increased growth and fecundity. Fecundity losses during poor conditions could be mitigated by partially or fully reallocating energy from gonadal production into somatic growth, thereby increasing potential fecundity in future years. However, when mortality was incorporated, those energetic re-routing strategies only increased lifetime reproductive output if we assumed that old (≥age 8) females produce more viable larvae than young females, and if the event occurred prior to age 8. Young females also increased output of larvae beyond age 8 if they skipped spawning or reallocated reproductive energy during good conditions, instead investing the surplus energy into additional somatic growth and enhancing future fecundity. Our results are consistent with recent estimates of growth rate variability in the chilipepper population, and with observations of young females of other rockfish species skipping spawning during poor conditions. Models like this may help improve stock assessment parameters and biological reference points for species with environmentally driven variability in size at age.

The periodicity of otolith growth increments (opaque and translucent zones) from adult red snapper (Lutjanus campechanus) was examined through a mark and recapture study (2005–2010), and laboratory holding of hatchery reared red snapper over a 2 year period (2002–2004). Wild red snapper (n = 295) were caught hook-and-line, marked with anchor tags, injected with oxytetracycline dihydrate (OTC), and released in the Gulf of Mexico 15–40 km south of Dauphin Island, Alabama. Marked fish were recaptured up to 2.8 years after release (n = 35) and sagittal otoliths were dissected, sectioned and examined under white and blue-violet light. The number of opaque growth zones past the OTC mark was compared to time at liberty for each fish and supported an annual periodicity of growth increment formation. Also, most (87%) of the hatchery reared fish showed two opaque zones that supported an annual increment formation rate. However, an unusual timing of opaque zone formation was shown for mark-recaptured fish. Based on known timing of OTC marking, otoliths from mark-recapture fish showed opaque zone formation from late summer (August) to early winter (December). This fall formation of opaque zones is in contrast to previous studies and its timing may relate to the end of spawning for this species.

This paper describes a simple and novel approach to calculate the line resistance of copper interconnects. The proposed methodology is simply based on a linear representation of the Cu resistivity vs. 1/S"C"u (S"C"u is the Cu cross-sectional area) in which the slope captures the net result of scattering phenomena in Cu.

In this study, a new type of materials, based on ethylene–vinyl acetate (EVA) copolymers, commercial organo-modified clays (organoclays) and multi-walled carbon nanotubes (MWNTs) has been prepared via direct melt blending. Both crude and purified MWNTs have been investigated. Thermal, flame retardant and tensile properties of the resulting new ternary nanocomposites have been measured and compared to the corresponding binary systems, i.e., EVA filled with either clays or carbon nanotubes. This new family of composites exhibits enhanced properties even at very low filler level usually inferior to 5 wt%. Interestingly, a synergistic effect arising from the combination of MWNTs and organoclays has been evidenced in some cases.

The wavelet transformation (WT) of a function y=f(x) with a wavelet of the nth order approximates the nth derivative of the function except for a constant scaling factor and a frequency-dependent phase shift. In the two-dimensional WT, the equivalent applies to the partial derivatives of a function z=f(x,y). If a digital terrain model (DTM) has been stored in form of wavelet coefficients (WCs), then the gradient and, if required, also curvature values can be directly deduced from the WCs. By means of special functions (test functions) whose derivatives are known, the scaling (`amplitude correction') and the displacement (`phase correction in the space domain') can be determined. The moments of the wavelets and the scaling functions (high and low-pass filters) make it possible to derive the approximation formulae in a clear and wavelet-independent manner.

Nanocomposites contain only a very small amount of modified layered silicates as fillers. The flame retardant mechanism in nanocomposites is based on the extremely effective char formation during decomposition as a result of combustion. This char provides a thermal protection for the polymer, prevents further decomposition, and also delays the release of flammable gases during combustion. The cone calorimeter is the most suitable instrument for measuring these effects. Nanocomposites have significant advantages over traditional flame retardant systems such as aluminium hydroxide or magnesium hydroxide.

Nanocomposites are a new class of materials in the plastics industry. Their extraordinary new or improved material properties are the result of the extremely fine distribution of modified layered silicates. This article describes the different production methods and the possible structures of nanocomposites, followed by a summary of the most important properties of nanocomposites demonstrating the possible applications.

Twelve healthy male subjects age range 24-40 y participated in the investigation. The trial was divided into 2 35-d periods. The 2 treatment regimens were: (i) 1 x 400 mg moxifloxacin tablet in the morning and 1 placebo tablet in the evening for 7 d; and (ii) 1 x 500 mg clarithromycin tablet in the morning and 1 x 500 mg clarithromycin tablet in the evening for 7 d. Each subject received firstly I treatment regimen and secondly the other treatment regimen. The wash-out period was 6 weeks between the two treatment regimens. Moxifloxacin caused significant decreases of enterococci and enterobacteria during the administration period while the numbers of staphylococci, streptococci, Bacillus and Candida were not affected. No impact on peptostreptococci, lactobacilli, Veillonella, Bacteroides or fusobacteria was observed, while bifidobacteria and clostridia decreased during moxifloxacin administration. The microflora was normalized after 35 d. Clarithromycin caused significant reduction of Escherichia coli while the numbers of enterococci, Enterobacter, Citrobacter, Klebsiella and Pseudomonas increased markedly. No significant changes in the numbers of staphylococci, streptococci, Bacillus and Candida were noticed. In the anaerobic microflora bifidobacteria, lactobacilli and clostridia were suppressed, while no changes in peptostreptococci, Veillonella, Bacteroides and fusobacteria were found. The microflora was normalized in all volunteers after 35 d.

The Global Consultation on Safe Water and Sanitation for the 1990s was an outstanding opportunity for participants from 102 developing countries along with over 60 External Support Agencies (ESA) to assess the experiences of the International Drinking Water Supply and Sanitation Decade 1981–1990 (IDWSSD) and to reach a consensus on strategies and approaches for complete and effective coverage of water supply and sanitation. The resulting New Delhi Statement summarizing the conclusions and recommendations of the Global Consultation was presented to the General Assembly in autumn 1990. As one of the positive results, the New Delhi Consultation agreed that the UN Agencies and other bodies should continue the coordination work of the Steering Committee for Water Supply and Sanitation. It also provided a basis for the restructuring and consolidation of the new Collaborative Council for Water Supply and Sanitation, which will form a continuous consultative body for all UN agencies, NGOs, other external support agencies and developing countries concerned with the water sector.

The progress behavior of evolution strategies (ES) using recombination is analyzed in this paper on the parabolic ridge. This test function represents landscapes far from the optimum. The ES algorithms with intermediate and dominant recombination are considered in the analysis. The derivations are presented for intermediate recombination. Thereafter, the formulae for dominant recombination are obtained using the so-called surrogate mutation model. In the analysis, the formulae are derived for the progress rate psi and for the stationary distance R(infinity) to the ridge axis. As a result, it will be shown that the progress rate psi can increase if recombination is applied. Simulations are used to show the appropriateness of the formulae derived.

A multiple-dose, randomized, double-blind, controlled, cross-over trial was performed in 12 healthy male subjects in order to investigate the effect of a 7-day treatment with moxifloxacin (400 mg orally, once daily) versus clarithromycin (500 mg orally, twice daily) on the normal oropharyngeal microflora. Moxifloxacin caused significant reductions in levels of alpha-streptococci and Neisseria cocci during the treatment period, while the numbers of gram-negative anaerobic bacteria increased markedly during moxifloxacin administration. Clarithromycin administration caused a suppression of micrococci and corynebacteria, while no significant changes were recorded in the anaerobic microflora. No new colonizing moxifloxacin-resistant strains were isolated during the investigation period.

Ru thin films were deposited by plasma enhanced atomic layer deposition using MethylCyclopentadienylPyrrolylRuthenium (MeCpPy)Ru and N2/NH3 plasma. The growth characteristics have been studied on titanium nitride or tantalum nitride substrates of various thicknesses. On SiO2, a large incubation period has been observed, which can be resolved by the use of a metal nitride layer of ∼ 0.8 nm. The growth characteristics of Ru layers deposited on ultra-thin metal nitride layers are similar to those on thick metal nitride substrates despite the fact that the metal nitride layers are not fully closed. Scaled Ru/metal nitride stacks were deposited in narrow lines down to 25 nm width. Thinning of the metal nitride does not impact the conformality of the Ru layer in the narrow lines. For the thinnest lines the Ru deposited on the side wall showed a more granular structure when compared to the bottom of the trench, which is attributed to the plasma directionality during the deposition process.

Kinetic experiments were made with pepsin in the presence of Cu2+ ions and additional Fe2+, Ni2+ or Zn3+ ions as sulphates. As a parameter of the pepsin activity the turnover-rate curves were determined with haemoglobin as a substrate. An important activation of the pepsin was obtained by Cu2+ additions of 5-10(-4) mole/1. When Cu2+ and Fe2+ ions were added to the reaction mixture at the same time, an additive effect of both metal cations was observed. A competitive effect of both metal cations was found in the combination of Cu2+/Ni2+ ions. Zn2+ addition did not influence the activation of pepsin caused by Cu2+ ions.

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