Simulation of Tail Weight Distributions in Biological Year 1986–2006 Landings of Brown Shrimp, Farfantepenaeus aztecus, from the Northern Gulf of Mexico Fishery

Size distribution within re- ported landings is an important aspect of northern Gulf of Mexico penaeid shrimp stock assessments. It reflects shrimp population characteristics such as numerical abundance of various sizes, age structure, and vital rates (e.g. recruitment, growth, and mortality), as well as effects of fishing, fishing power, fishing practices, sampling, size-grading, etc. The usual measure of shrimp size in archived landings data is count (C) the number of shrimp tails (abdomen or edible portion) per pound (0.4536 kg). Shrimp are marketed and landings reported in pounds within tail count categories. Statistically, these count categories are count class intervals or bins with upper and lower limits expressed in C. Count categories vary in width, overlap, and frequency of occurrence within the landings. The upper and lower limits of most count class intervals can be transformed to lower and upper limits (respectively) of class intervals expressed in pounds per shrimp tail, w, the reciprocal of C (i.e. w = 1/C). Age based stock assessments have relied on various algorithms to estimate numbers of shrimp from pounds landed within count categories. These algorithms required un- derlying explicit or implicit assumptions about the distribution of C or w. However, no attempts were made to assess the actual distribution of C or w. Therefore, validity of the algorithms and assumptions could not be determined. When different algorithms were applied to landings within the same size categories, they produced different estimates of numbers of shrimp. This paper demonstrates a method of simulating the distribution of w in reported biological year landings of shrimp. We used, as examples, landings of brown shrimp, Farfantepenaeus aztecus, from the northern Gulf of Mexico fishery in biological years 1986–2006. Brown shrimp biological year, Ti, is defined as beginning on 1 May of the same calendar year as Ti and ending on 30 April of the next calendar year, where subscript i is the place marker for biological year. Biological year landings encompass most if not all of the brown shrimp life cycle and life span. Simulated distributions of w reflect all factors influencing sizes of brown shrimp in the landings within a given biological year. Our method does not require a priori assumptions about the parent distributions of w or C, and it takes into account the variability in width, overlap, and frequency of occurrence of count categories within the landings. Simulated biological year distributions of w can be transformed to equivalent distributions of C. Our method may be useful in future testing of previously applied algorithms and development of new estimators based on statistical estimation theory and the underlying distribution of w or C. We also examine some applications of biological year distributions of w, and additional variables derived from them

AN INVESTIGATION INTO THE USE AND USEFULNESS OF SECURITY SO TWARE IN DETECTING COMPUTER ABUSE

Computer security remains an important issue in the management of organizational information systems. Losses resulting from computer abuse and errors are substantial, and IS managers continue to cite security and control as a key management issue. With continued expansion of clistributed data processing and storage, the need to both prevent and detect violations also increases. This latter aspect, detection of computer abuse incidents, is the focus of this study. This empirical study examines the prevalence and sophistication of security software system installations across the United States. Using a victimization survey of 528 randomly-selected DPMA members, the study examines discovered incidents of computer abuse in organizations and attempts to identify relationships between comprehensive (i.e., sophisticated) security software and successful discovery of abuse. More comprehensive security software was found to be associated with greater ability to identify perpetrators of abuse and to discover more serious computer abuse incidents. Larger organizations used both a greater number and more sophisticated security software systems than smaller organizations. Wholesale/retail trade organizations used less comprehensive software than average, while manufacturing organizations and public utilities used more comprehensive software. Surprisingly, no relationships were found between the maturity of an organization\u27s security function and the number and/or sophistication of security software systems utilized

Analyzing the Variable Pain

This presentation is a thorough analysis of participant physical pain and physical impairment within the given study. This data was conducted through an EMA study. The smartphone apps TigerAware and Qualtrics were used to give participants surveys throughout the course of ten days. The participants were undergraduate students at UMSL who received extra credit for participating in the study. Out of the 126 participants, 13 were male and 113 female. The surveys focused on comparing the relationship between alcohol usage and other variables. These surveys had questions relating to alcohol usage, marijuana usage, mood, pain, and questions about daily functioning. Participants\u27 level of physical pain and physical impairment were analyzed in correlation to alcohol usage and other variables. In this study, the more pain someone experiences, the more physical impairment they will have. Other possible correlations are found, although the data was not significant, future research should be conducted to analyze the data further

Epigene and Hypogene Karst Manifestations of the Castile Formation: Eddy County, New Mexico and Culberson County, Texas, USA

Permian evaporites of the Castile Formation crop out over ~1,800 km2 in the western Delaware Basin (Eddy County, New Mexico and Culberson County, Texas, USA) with abundant and diverse karst manifestations. Epigene karst occurs as well-developed karren on exposed bedrock, while sinkholes dominate the erosional landscape, including both solutional and collapse forms. Sinkhole analyses suggest that more than half of all sinks are the result of upward stoping of subsurface voids, while many solutional sinks are commonly the result of overprinting of collapsed forms. Epigene caves are laterally limited with rapid aperture decreases away from insurgence, with passages developed along fractures and anticline fold axes. Hypogene karst occurs as diverse manifestations, forming the deepest and longest caves within the region as well as abundant zones of brecciation. Hypogene caves exhibit a wide range of morphologies from complex maze and anastomotic patterns to simple, steeply dipping patterns, but all hypogene caves exhibit morphologic features (i.e. risers, outlet cupolas and half-tubes) that provide a definitive suite of evidence of dissolution within a mixed convection (forced and free convection) hydrologic system. Extensive blanket breccias, abundant breccia pipes and numerous occurrences of calcitized evaporites indicate widespread hypogene speleogenesis throughout the entire Castile Formation. Although most cave and karst development within the Castile outcrop region appears to have hypogene origins, epigene processes are actively overprinting features, creating a complex speleogenetic evolution within the Castile Formation

Symmetric Fibonaccian distributive lattices and representations of the special linear Lie algebras

We present a family of rank symmetric diamond-colored distributive lattices that are naturally related to the Fibonacci sequence and certain of its generalizations. These lattices re-interpret and unify descriptions of some un- or differently-colored lattices found variously in the literature. We demonstrate that our symmetric Fibonaccian lattices naturally realize certain (often reducible) representations of the special linear Lie algebras, with weight basis vectors realized as lattice elements and Lie algebra generators acting along the order diagram edges of each lattice. We present evidence that each such weight basis is, in a certain sense, uniquely associated with its lattice. We provide new descriptions of the lattice cardinalities and rank generating functions and offer several conjectures/open problems. Throughout, we make connections with integer sequences from the OEIS.Comment: 18 page

Improving measurements of SF6 for the study of atmospheric transport and emissions

Sulfur hexafluoride (SF6) is a potent greenhouse gas and useful atmospheric tracer. Measurements of SF6 on global and regional scales are necessary to estimate emissions and to verify or examine the performance of atmospheric transport models. Typical precision for common gas chromatographic methods with electron capture detection (GC-ECD) is 1–2%. We have modified a common GC-ECD method to achieve measurement precision of 0.5% or better. Global mean SF6 measurements were used to examine changes in the growth rate of SF6 and corresponding SF6 emissions. Global emissions and mixing ratios from 2000–2008 are consistent with recently published work. More recent observations show a 10% decline in SF6 emissions in 2008–2009, which seems to coincide with a decrease in world economic output. This decline was short-lived, as the global SF6 growth rate has recently increased to near its 2007–2008 maximum value of 0.30±0.03 pmol mol−1 (ppt) yr−1 (95% C.L.)

SMAF: A Soil Health Assessment Tool

The Soil Management Assessment Framework (SMAF) was developed to help quantify soil quality/health effects of tillage, crop rotation, and other soil management practices. Our objective was to determine if the SMAF could detect soil health differences after growing a single winter triticale (X Triticosecale Wittmack) crop. Soil samples were collected from 0 to 7.5- and 7.5 to 15- cm depth increments during the 2003 – 2004 and 2004 – 2005 growing seasons near Ames and Lewis, IA, and analyzed for several potential soil quality indicators. The SMAF analysis showed higher soil quality ratings for surface than subsurface samples. It also showed that a single winter grain crop can significantly improve soil quality after either corn (Zea mays L.) or soybean (Glycine max [L.] Merr.). Finally, in response to increasing interest in soil health assessments, a detailed appendix is attached to provide guidance for future soil health assessments

State of the art: iterative CT reconstruction techniques

Owing to recent advances in computing power, iterative reconstruction (IR) algorithms have become a clinically viable option in computed tomographic (CT) imaging. Substantial evidence is accumulating about the advantages of IR algorithms over established analytical methods, such as filtered back projection. IR improves image quality through cyclic image processing. Although all available solutions share the common mechanism of artifact reduction and/or potential for radiation dose savings, chiefly due to image noise suppression, the magnitude of these effects depends on the specific IR algorithm. In the first section of this contribution, the technical bases of IR are briefly reviewed and the currently available algorithms released by the major CT manufacturers are described. In the second part, the current status of their clinical implementation is surveyed. Regardless of the applied IR algorithm, the available evidence attests to the substantial potential of IR algorithms for overcoming traditional limitations in CT imaging

Development of Nondestructive Tests for the Experimental Gas-Cooled Reactor Fuel Element

The Title I design fuel assembly and each of its components for the Experimental Gas-cooled Reactor are described. The development of the specific nondestructive testing techniques for the evaluation of the components and the fabricated fuel capsule is presented. These techniques include penetrants, pulse- echo and resonance ultrasonics, radiography, eddy-currents, helium leak testing, and others. Discussion is made on the capabilities and limitations of these techniques for the specific inspection problems and reasons presented for the selection of the inspection requirements. (auth