bluuebunny/crossref_metadata_2025 huggingface dataset:
Metabolic and Body Composition Factors in Subgroups of Obesity: What Do We Know?
Authors: Karelis Antony D. , St-Pierre David H. , Conus Florence , Rabasa-Lhoret Remi , Poehlman Eric T.
Published: June 2004

Obesity is thought to be a heterogeneous disorder with several possible etiologies; therefore, by examining subtypes of obesity we attempt to understand obesity’s heterogeneous nature. The purpose of this review was to investigate the roles of metabolic, body composition, and cardiovascular disease risk in subtypes of obesity. We briefly consider two subtypes of obesity that have been identified in the literature. One subset of individuals, termed the metabolically healthy, but obese (MHO), despite having large amounts of fat mass compared with at risk obese individuals shows a normal metabolic profile, but remarkably normal to high levels of insulin sensitivity. Preliminary evidence suggests that this could be due at least in part to lower visceral fat levels and earlier onset of obesity. A second subset, termed the metabolically obese, but normal weight (MONW), present with normal body mass index, but have significant risk factors for diabetes, metabolic syndrome, and cardiovascular disease, which could be due to higher fat mass and plasma triglycerides as well as higher visceral fat and liver content. We also briefly consider the potential role of adipose and gastrointestinal hormonal profiles in MHO and MONW individuals, which could lead to a better understanding of potential factors that may regulate their body composition. This information will eventually be invaluable in helping us understand factors that predispose to or protect obese individuals from metabolic and cardiovascular disease. Collectively, a greater understanding of the MHO and MONW individual has important implications for therapeutic decision making, the characterization of subjects in research protocols, and medical education.
Insulin Resistance Syndrome in Children
Authors: Ten Svetlana , Maclaren Noel
Published: June 2004

The insulin resistance syndrome (syndrome X, metabolic syndrome) has become the major health problem of our times. Associated obesity, dyslipidemia, atherosclerosis, hypertension, and type 2 diabetes conspire to shorten life spans, while hyperandrogenism with polycystic ovarian syndrome affect the quality of life and fertility of increasing numbers of women. Whereas a growing number of single genetic diseases affecting satiety or energy metabolism have been found to produce the clinical phenotype, strong familial occurrences, especially in racially prone groups such as those from the Indian subcontinent, or individuals of African, Hispanic, and American Indian descents, together with emerging genetic findings, are revealing the polygenetic nature of the syndrome. However, the strong lifestyle factors of excessive carbohydrate and fat consumption and lack of exercise are important keys to the phenotypic expression of the syndrome. The natural history includes small for gestational age birth weight, excessive weight gains during childhood, premature pubarche, an allergic diathesis, acanthosis nigricans, striae compounded by gynecomastia, hypertriglyceridemia, hepatic steatosis, premature atherosclerosis, hypertension, polycystic ovarian syndrome, and focal glomerulonephritis appearing increasingly through adolescence into adulthood. Type 2 diabetes, which develops because of an inherent and/or an acquired failure of an insulin compensatory response, is increasingly seen from early puberty onward, as is atheromatous disease leading to coronary heart disease and stroke. A predisposition to certain cancers and Alzheimer’s disease is also now recognized. The looming tragedy from growing numbers of individuals affected by obesity/insulin resistance syndrome requires urgent public health approaches directed at their early identification and intervention during childhood. Such measures include educating the public on the topic, limiting the consumption of sucrose-containing drinks and foods with high carbohydrate and fat contents, and promoting exercise programs in our nation’s homes and schools.
A Pair of Seven-Coordinate Oxorhenium Complexes: [ReIVO(tpen)]2+ and [ReVO(tpen)]3+ (tpen = N,N,N′,N′-Tetrakis(2-pyridylmethyl)ethylenediamine)
Authors: Jin Hai-Ying , Ikari Shinji , Kobayashi Kimiko , Umakoshi Keisuke , Sugimoto Hideki , Mitani Ayako , Abe Masaaki , Sasaki Yoichi , Ito Tasuku
Published: June 2004

A pair of seven-coordinate oxorhenium complexes of N,N,N′,N′-tetrakis(2-pyridylmethyl)ethylenediamine (tpen), [ReIVO(tpen)](ClO4)2 (1) and [ReVO(tpen)](ClO4)3 (2), and its R-1,2-propylenediamine analogue (R-tppn), have been prepared. X-ray structural analyses indicate that the structure of complex cation in 1 is best described as a monocapped trigonal prism with the oxo ligand as a cap. The four pyridylmethyl nitrogen atoms are essentially planar. On the other hand, the structure of complex cation in 2 is approximated as a pentagonal bipyramid, in which the four pyridyl nitrogen atoms take a tetrahedrally distorted arrangement. The structural difference is discussed in terms of different d-electron numbers. The μeff value of 1 at 300 K is 1.99 B.M. which corresponds to S = 1/2, while 2 is diamagnetic. The complexes show a reversible redox wave (Re(IV/V)) at +0.31 V vs Ag/AgCl in 0.1 M (n-C4H9)4NPF6 acetonitrile solution. In acetonitrile–aqueous buffer solution (2 < pH < 12), in addition to a pH independent Re(IV/V) wave at +0.18 V vs Ag/AgCl, a pH-dependent quasi-reversible Re(III/IV) wave with a slope of −0.056 V/pH-unit was observed, indicating that the relevant Re(III) species is [Re(OH)(tpen)]2+. The weak absorption peaks of 1 (in acetonitrile) at 836 and 511 nm and those of 2 (in water) at 800, 633, and 408 nm may be assigned to d–d transitions, while the peaks at 428, 381, and 361 nm of 1 may be of charge transfer origin.
Fragilide A, a Novel Diterpenoid from Junceella fragilis
Authors: Sung Ping-Jyun , Lin Mei-Ru , Chen Wei-Chen , Fang Lee-Shing , Lu Chung-Kuang , Sheu Jyh-Horng
Published: June 2004

A novel briarane-type diterpenoid, fragilide A (1), has been isolated from the Taiwanese gorgonian coral Junceella fragilis. The structure, including the relative configuration of this new metabolite, was elucidated by spectroscopic methods.
Enhanced Dichlorodifluoromethane Decomposition with Selective Fluorine Absorption by Acidic Fluorinated Magnesium Oxide
Authors: Tamai Tsukasa , Inazu Koji , Aika Ken-ichi
Published: June 2004

CCl2F2 decomposition with simultaneous halogen absorption by partially fluorinated MgO (MgF2–MgO) was studied, focusing on the effects of the acidity of the surface. CCl2F2 decomposition by MgF2–MgO was greatly promoted by fluorination of MgO at 10 mol% or higher. CCl2F2 decomposition was not a catalytic process over MgF2–MgO but basically a selective fluorine absorption reaction with MgO to form MgF2. Chlorine was released in the form of CCl4 regardless of reaction temperature and degree of fluorination of MgO due to low reactivity to CCl4. NH3-TPD and pyridine adsorption experiments were carried out to characterize the acid sites on MgF2–MgO samples. The amount of acid sites became maximum for 10% MgF2–MgO and the strength of acid sites increased as fluorination proceeded. CCl2F2 decomposition was revealed to be initiated by Lewis acid sites on MgF2–MgO formed by CCl2F2 decomposition as well as by fluorination with hydrofluoric acid aqueous solution. Thus, formation of the Lewis acid sites was considered to be the key step for efficient CCl2F2 decomposition with selective fluorine absorption.
Mass Spectrometry in the Characterisation of Cereal Seed Proteins
Authors: Cunsolo Vincenzo , Foti Salvatore , Saletti Rosaria
Published: June 2004

In less then a decade, applications of matrix-assisted laser desorption/ionisation (MALDI) and electrospray ionisation (ESI) mass spectrometry to the investigation of prolamins have rapidly evolved from measurements of the molecular mass of isolated proteins to a proteomic approach attempting to characterise the complete protein pattern in the seed. Mass spectrometry is currently making significant contributions to the understanding of the composition and structure of the gluten proteins and, in turn, to the elucidation of structure–function relationships. Results obtained using mass spectrometry, including determination of the molecular masses of prolamins, direct verification of gene-derived sequences, determination of the number of cysteine residues and localisation of disulphide bonds, investigation of the gluten toxicity for celiac patients, qualitative and quantitative determination of gliadins in food and determination of the protein pattern and its modification during seed maturation by proteomic approaches, are summarised here, to illustrate current trends and individuate possible future perspectives.
On the Equivalence of Two Expected Average Cost Criteria for Semi-Markov Control Processes
Authors: Jaśkiewicz A.
Published: June 2004

The two expected average costs used in the theory of semi-Markov control processes with a Borel state space are considered. Under some stochastic stability conditions, we prove that the two criteria are equivalent in the sense that they lead to the same optimality equation.
Optimal Interventions in Countable Jump Markov Processes
Authors: Piunovskiy A. B.
Published: June 2004

In this paper an intervention refers to an immediate change of the state of the system; between interventions, the continuous-time jump Markov process is uncontrollable, with “natural” jump intensities. The multicriteria control problem for such a model is considered, and the constrained version is investigated with the help of the Lagrange multipliers technique. All of the theory is illustrated by an example of the optimal control of epidemic with carriers.
On Multivariate Discrete Moment Problems and Their Applications to Bounding Expectations and Probabilities
Authors: Mádi-Nagy Gergely , Prékopa András
Published: June 2004

The discrete moment problem (DMP) has been formulated as a methodology to find the minimum and/or maximum of a linear functional acting on an unknown probability distribution, the support of which is a known discrete (usually finite) set, where some of the moments are known. The moments may be binomial, power, or of more general type. The multivariate discrete moment problem (MDMP) has been initiated by the second-named author, who developed a linear programming theory and methodology for the solution of the DMPs and MDMPs under some assumptions that concern the divided differences of the coefficients of the objective function. The central results in this respect are those that concern the structure of the dual feasible bases. In this paper, further results are presented in connection with MDMPs for the case of power and binomial moments. The main theorem (Theorem 3.1) and its applications help us to find dual feasible bases under the assumption that the objective coefficient function has nonnegative divided differences of a given total order, and further divided differences are nonnegative in each variable. Any dual feasible basis provides us with a bound for the discrete function that consists of the coefficients of the objective function and also for the linear functional. The latter bound is sharp if the basis is primal feasible as well. The combination of a dual feasible basis structure theorem and the dual method of linear programming is a powerful tool to find the sharp bound for the true value of the functional, i.e., the optimum value of the objective function. The lower and upper bounds are frequently close to each other even if the number of utilized moments is relatively small. Numerical examples are presented for bounding the expectations of functions of random vectors as well as probabilities of Boolean functions of event sequences.
Discounted Multiarmed Bandit Problems on a Collection of Machines with Varying Speeds
Authors: Dunn R. T. , Glazebrook K. D.
Published: June 2004

This paper is the first to consider general multiarmed bandit problems on parallel machines working at different speeds. Block allocation policies make a once-for-all allocation of bandits to machines at time zero. In this class we describe how to achieve Blackwell optimality under given conditions. The block allocation policy identified allocates the bandits with the largest guaranteed reward rates to the machines operating at greatest speed. This policy is shown to be average-reward optimal in the class of general (nonanticipative, nonidling) policies.
On Metric Generators of Graphs
Authors: Sebő András , Tannier Eric
Published: June 2004

We study generators of metric spaces—sets of points with the property that every point of the space is uniquely determined by the distances from their elements. Such generators put a light on seemingly different kinds of problems in combinatorics that are not directly related to metric spaces. The two applications we present concern combinatorial search: problems on false coins known from the borderline of extremal combinatorics and information theory; and a problem known from combinatorial optimization—connected joins in graphs.

We use results on the detection of false coins to approximate the metric dimension (minimum size of a generator for the metric space defined by the distances) of some particular graphs for which the problem was known and open. In the opposite direction, using metric generators, we show that the existence of connected joins in graphs can be solved in polynomial time, a problem asked in a survey paper of Frank. On the negative side we prove that the minimization of the number of components of a join is NP-hard.

We further explore the metric dimension with some problems. The main problem we are led to is how to extend an isometry given on a metric generator of a metric space.
Synthesis of 2-Commodity Flow Networks
Authors: Hassin Refael , Levin Asaf
Published: June 2004

We investigate network design under volatile conditions of link failures and traffic overload. Our model is a nonsimultaneous 2-commodity problem. We characterize the feasible solutions and, using this characterization, we reduce the size of the linear program. For 0/1 requirements we present a closed fractional optimal solution, a closed integer-capacities optimal solution, and 7/6-approximation for the case in which integer 2-commodity flows are required.
On Hochbaum's Proximity-Scaling Algorithm for the General Resource Allocation Problem
Authors: Moriguchi Satoko , Shioura Akiyoshi
Published: June 2004

It is pointed out that the polynomial-time scaling algorithm by Hochbaum does not work correctly for the general resource allocation problem. Hochbaum's algorithm increases a variable by one unit if the variable cannot feasibly be increased by the scaling unit. We modify the algorithm to increase such a variable by the largest possible amount and show that with this modification the algorithm works correctly. The effect is to modify the factor F in the running time of Hochbaum's algorithm for finding whether a certain solution is feasible by the factor F̃ of finding the maximum feasible increment (also called the saturation capacity). Therefore, the corrected algorithm runs in O(n(log n + F̃) log(B/n)) time.
On Average Reward Semi-Markov Decision Processes with a General Multichain Structure
Authors: Jianyong L. , Xiaobo Z.
Published: June 2004

In this paper we investigate average reward semi-Markov decision processes with a general multichain structure using a data-transformation method. By solving the transformed discrete-time average Markov decision processes, we can obtain significant and interesting information on the original average semi-Markov decision processes. If the original semi-Markov decision processes satisfy some appropriate conditions, then stationary optimal policies in the transformed discrete-time models are also optimal in the original semi-Markov decision processes.
A Combinatorial Characterization of Higher-Dimensional Orthogonal Packing
Authors: Fekete Sándor P. , Schepers Jörg
Published: June 2004

Higher-dimensional orthogonal packing problems have a wide range of practical applications, including packing, cutting, and scheduling. Previous efforts for exact algorithms have been unable to avoid structural problems that appear for instance in two- or higher-dimensional space. We present a new approach for modeling packings, using a graph-theoretical characterization of feasible packings. Our characterization allows it to deal with classes of packings that share a certain combinatorial structure, instead of having to consider one packing at a time. In addition, we can make use of elegant algorithmic properties of certain classes of graphs. This allows our characterization to be the basis for a successful branch-and-bound framework.

This is the first in a series of papers describing new approaches to higher-dimensional packing.
Almost Every Convex or Quadratic Programming Problem Is Well Posed
Authors: Ioffe A. D. , Lucchetti R. E. , Revalski J. P.
Published: June 2004

We provide an abstract principle aimed at proving that classes of optimization problems are typically well posed in the sense that the collection of ill-posed problems within each class is σ-porous. As a consequence, we establish typical well-posedness in the above sense for unconstrained minimization of certain classes of functions (e.g., convex and quasi-convex continuous), as well as of convex programming with inequality constraints. We conclude the paper by showing that the collection of consistent ill-posed problems of quadratic programming of any fixed size has Lebesgue measure zero in the corresponding Euclidean space.
MAP/M/cQueue with Constant Impatient Time
Authors: Choi Bong Dae , Kim Bara , Zhu Dongbi
Published: June 2004

We consider a MAP/M/c queue where a customer who cannot begin to receive his service for a fixed time is lost. We find a simple Markov process by using a concept of virtual waiting time and then obtain the stationary distribution of the Markov process. We find several performance measures such as loss probability, waiting time distribution, mean waiting time, and mean queue size by using the results of the stationary distribution of the Markov process.
Large Deviations of Square Root Insensitive Random Sums
Authors: Jelenković Predrag R. , Momčilović Petar
Published: June 2004

We provide a large deviation result for a random sum [Formula: see text], where Nx is a renewal counting process and {Xn}n≥0 are i.i.d. random variables, independent of Nx, with a common distribution that belongs to a class of square root insensitive distributions. Asymptotically, the tails of these distributions are heavier than e−√x and have zero relative decrease in intervals of length √x, hence square root insensitive. Using this result we derive the asymptotic characterization of the busy period distribution in the stable GI/G/1 queue with square root insensitive service times; this characterization further implies that the tail behavior of the busy period exhibits a functional change for distributions that are lighter than e−√x.
The Game of Normal Numbers
Authors: Lehrer Ehud
Published: June 2004

We introduce a two-player game where at each period one player, say, Player 2, chooses a distribution and the other player, Player 1, chooses a realization. Player 1 wins the game if the sequence of realized outcomes is normal with respect to the sequence of distributions. We present a pure winning strategy of Player 1 and thereby provide a universal algorithm that generates a normal sequence for any discrete stochastic process. It turns out that to select the nth digit, the algorithm conducts O(n 2) calculations. The proof uses approachability in infinite-dimensional spaces (Lehrer 2002).
Error Bound Moduli for Conic Convex Systems on Banach Spaces
Authors: Zheng Xi Yin , Ng Kung Fu
Published: June 2004

We give two explicit formulas which express the error bound moduli for conic convex systems, one in terms of directional derivative, and the other in terms of the coderivative. As applications, we study error bounds for systems of infinitely many convex inequalities.
A Method to Count Pirarucu Arapaima gigas: Fishers, Assessment, and Management
Authors: Castello Leandro
Published: June 2004

The giant and obligate air-breathing fish pirarucu Arapaima gigas (also known as arapaima) is a species endemic to the Amazon Basin that is increasingly managed by artisanal fishers because of government failure to control the fishery. In this study the ability of experienced artisanal fishers to count the number of pirarucu at the moment of aerial breathing was assessed. Counts were strongly correlated (r = 0.98) with mark–recapture abundance estimates calculated for the same populations. The potential for trained fishers to train other fishers to count pirarucu without slow and expensive mark–recapture work was also assessed and confirmed. Not only are the counts a cost-effective method for assessing pirarucu populations, they also allow fisher participation in decision making and contribute to effective management. The increasing number of community-based management schemes can now be matched with the training of fishers to count pirarucu.
Impact of Alewife Introduction on Walleye and White Bass Condition in Lake McConaughy, Nebraska, 1980-1995
Authors: Porath Mark T. , Peters Edward J. , Eichner Darrol L.
Published: June 2004

We examined relative weight (Wr) relationships of walleye Stizostedion vitreum and white bass Morone chrysops before and after the addition of alewife Alosa pseudoharengus in Lake McConaughy, Nebraska, where gizzard shad Dorosoma cepedianum had been the primary prey. Walleyes and white bass were collected in fall gillnetting surveys from 1980 to 1995. A general linear model was constructed to determine the least-squares means of walleye and white bass Wrs by length category and year. Contrast statements were used to test for significant differences in the annual Wrs of walleye and white bass population length categories before and after the establishment of alewives. The annual mean Wrs of walleyes of stock to quality (S-Q), quality to preferred (Q-P), and preferred to memorable (P-M) lengths and Q-P-length white bass increased significantly, whereas that of S-Q-length and P-M-length white bass decreased significantly after 1988. The introduction of alewives changed the body condition of walleyes and white bass in Lake McConaughy, Nebraska.
Recruitment Dynamics of the 1971–1991 Year-Classes of Lake Trout in Michigan Waters of Lake Superior
Authors: Richards Jessica M. , Hansen Michael J. , Bronte Charles R. , Sitar Shawn P.
Published: June 2004

In the 1950s, populations of lake trout Salvelinus namaycush in Lake Superior collapsed because of excessive exploitation and predation by sea lampreys Petromyzon marinus. Restoration began in the 1950s with the stocking of juvenile, hatchery-reared lake trout and controls on fisheries and sea lampreys. Partial restoration was declared in 1996 because wild fish made up most of the populations in many areas, especially in Michigan waters, so stocking was dramatically curtailed in most areas. We evaluated the production of age-7 lake trout (recruits) by age-8 and older wild and stocked parental lake trout (spawners). Using Ricker stock–recruitment models, we also evaluated the effects of large-mesh (114-mm stretch measure) gill-net effort on wild lake trout recruitment in Michigan waters of Lake Superior during 1970–1998. In general, the density of wild lake trout spawners increased, whereas that of stocked lake trout spawners decreased in all management areas investigated. The density of recruits was best described by the combined density of wild and stocked parents, which suggested similar reproductive contributions for both. Recruitment rates declined significantly with increasing spawner density in four of the five management areas and suggested that carrying capacities were reached and exceeded, which may serve as an indicator of population restoration. We conclude that both wild and stocked lake trout have contributed to the recruitment of lake trout in Michigan waters of Lake Superior. Large-mesh gill-net fishing effort varied in all Michigan management areas but did not account for the significant variation in wild lake trout recruitment. We conclude that levels of large-mesh gill-net fishing effort during 1970–1998 were not having an appreciable effect on wild lake trout recruitment in Michigan waters of Lake Superior.
Mortality and Long-Term Retention of Passive Integrated Transponder Tags by Spring Chinook Salmon
Authors: Dare Matthew R.
Published: June 2004

I monitored long-term mortality and retention rates of passive integrated transponder (PIT) tags for 145,000 juvenile spring chinook salmon Oncorhynchus tshawytscha tagged as part of a large-scale tagging project. A total of 325 PIT tagged mortalities were collected during the 28-d study. Mortalities were collected, on average, 11 d after tagging, indicating that direct mortality due to tagging was rare. The mortality rate observed during the study was less than 1.0%. With the exception of the first day of tagging, 24-h retention was greater than 99.0%. A total of 113 shed tags were collected following the first day of tagging, corresponding to a 24-h retention rate of 98.1%. The overall retention rate for the study was 99.996%. I found no statistical relationship between the frequency of shedding and fish length or time of tagging. Although the relationship is not quantifiable, the frequency of sheds appeared to be linked to the experience of tagging personnel at the start of the tagging project and the continuity of personnel at a tagging station.
Kernel Density Estimates of Linear Home Ranges for Stream Fishes: Advantages and Data Requirements
Authors: Vokoun Jason C.
Published: June 2004

Kernel density estimates of linear home range can increase the information content of the home range estimate. Particularly in lotic systems, univariate kernel density estimates have desirable properties relative to simple reporting of linear ranges. Kernel density estimates are calculated from a set of relocation points (i.e., radiotelemetry contacts) that can be interpreted as a utilization distribution (UD). The UD estimates the amount of time spent at a given point within the home range. The amount of time that elapses between relocations (sampling interval), total number of relocations (sample size), and bandwidth (smoothing applied to the estimate) are important considerations when using kernel density estimates. Monte Carlo simulations using unimodal and bimodal distributions sampled randomly at sample sizes of 10-100 and three automated bandwidth selection procedures (simple normal reference, Silverman's rule of thumb, and Sheather-Jones plug-in) suggested that at sample sizes of 30 or more kernel density estimates began to level off and the largest gains in accuracy were evident for all three bandwidth selection procedures. I present example kernel density estimates for flathead catfish Pylodictis olivaris and use them to illustrate methods of reporting data. A literature review found relatively few examples of home range delineation for stream fishes but confirmed that the most common practice was to report the distance between the most upstream and downstream relocations. Sample size information was often inadequately reported in the reviewed literature.
Postrelease Performance of Hatchery Yearling and Subyearling Fall Chinook Salmon Released into the Snake River
Authors: Connor William P. , Smith Steven G. , Andersen Todd , Bradbury Steven M. , Burum Douglas C. , Hockersmith Eric E. , Schuck Mark L. , Mendel Glen W. , Bugert Robert M.
Published: June 2004

Two rearing treatments are used at Lyons Ferry Hatchery to produce yearling (age-1) and subyearling (age-0) fall Chinook salmon Oncorhynchus tshawytscha for supplementing production of wild fish in the Snake River. We compared four indicators of yearling and subyearling postrelease performance, namely, seaward movement, condition factor, growth rate, and survival. A standard rearing treatment was used to grow yearlings slowly for 14 months to sizes of 152–162 mm (mean fork length). A second standard rearing treatment was used to grow medium subyearlings at a moderate rate for 5 months to 84–89 mm. Two modified rearing treatments were used to produce large subyearlings that were grown rapidly to 90–103 mm and small subyearlings that were grown slowly to 70–76 mm. We released yearlings in April and subyearlings in June on the typical supplementation schedule. Seaward movement, condition factor, growth, and survival varied among rearing treatments. Yearlings moved seaward fastest for reasons related to their large size. Yearlings had the lowest postrelease condition factors and growth rates because they were released when temperatures were cool and they moved seaward quickly, spending little time to feed. Yearlings had the highest survival because they were released when the water was cool, they moved seaward quickly, and their large size reduced susceptibility to predation. Small subyearlings moved seaward the slowest because of their small size and slow growth before release. Small subyearlings had the highest postrelease condition factors and highest growth rates because they lingered and were exposed to relatively high temperatures that were favorable for growth. Small subyearlings had the lowest survival because they lingered and were exposed to low flow and warm water for long durations and their small size increased susceptibility to predation. We conclude that fall Chinook salmon performance after release from Lyons Ferry Hatchery is influenced by release date and by rearing treatment effects on size, prerelease growth rate, and postrelease behavior.
Predation on Juvenile Salmonids by Smallmouth Bass in the Lower Granite Reservoir System, Snake River
Authors: Naughton George P. , Bennett David H. , Newman Ken B.
Published: June 2004

We estimated the consumption of juvenile salmon Oncorhynchus spp. and steelhead O. mykiss by smallmouth bass Micropterus dolomieu in the tailrace and forebay of the Lower Granite Dam and compared this consumption with that in the two major river arms of the upper Lower Granite Reservoir, Snake River, Idaho–Washington. We examined over 9,700 smallmouth bass stomachs from April through August during 1996 and 1997. Juvenile salmonids were not a major component of smallmouth bass diets by weight and number at any location in either 1996 or 1997. Of the approximately 8,600 stomach samples containing food items, only 67 had juvenile salmonid remains. Juvenile salmonids accounted for approximately 11% of smallmouth bass diets by weight in the forebay in 1996 and 5% in the Snake and Clearwater river arms in 1997, with smaller proportions at other locations. Crustaceans and nonsalmonid fishes were the dominant prey items by weight at all locations in 1996 and 1997 except for the Snake River arm in 1996, where macroinvertebrates were dominant. Monthly consumption rates (smolts/bass/d) of juvenile salmonids by smallmouth bass were highest in the forebay (0.02) in April 1996 and in the restricted zone of the forebay (0.05) in July 1997. We estimated that approximately 17,500 (1996: 6,728; 1997: 10,809) juvenile salmonids were consumed by smallmouth bass from April through August in 1996 and 1997. High flows and resulting lower water temperatures and higher turbidity in the Lower Granite Reservoir during our study probably affected salmonid predation rates by smallmouth bass. Management efforts directed at enhancing migratory conditions for juvenile salmonids (e.g., higher flows, lower water temperatures, and higher turbidity) will probably also reduce predation from smallmouth bass.
Effects of Intraspecific Density and Environmental Variables on Electrofishing Catchability of Brown and Rainbow Trout in the Colorado River
Authors: Speas David W. , Walters Carl J. , Ward David L. , Rogers R. Scott
Published: June 2004

We investigated electrofishing catchability (q) for brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss in the Colorado River, Grand Canyon National Park, Arizona, over a range of fish densities, water temperatures, turbidities, conductivities, shoreline types, and seasons. The covariance of q with rainbow trout density strongly resembled random distributions, thereby suggesting no relationship between q and rainbow trout density. The catchability of rainbow trout was greater in turbid water (≥480 nephelometric turbidity units (NTU)) than in clear water (≤10 NTU), although lower water temperature may have contributed to this effect. The catchability of rainbow trout was greatest over sand–silt shorelines. The catchability of brown trout increased sharply to levels above those predicted from random chance up to about 0.025 fish/m2 and then assumed an asymptotic or declining relationship with intraspecific fish density. In contrast to the situation with rainbow trout, the catchability of brown trout was higher over rocky shorelines (cobbles, boulders, and bedrock) than sand–silt shorelines, suggesting that the variability of q in relation to shoreline type is species specific. We hypothesize that the catchability of rainbow trout is influenced more by environmental variables than by density. We also hypothesize that brown trout catchability varies with density because a greater proportion of fish occur in shallow, nearshore areas (where electrofishing is most effective) when fish density is high. This effect is enhanced by high catchability over rocky substrates. Our findings emphasize the need to understand the biological and environmental factors affecting electrofishing catchability, especially in monitoring programs that rely on catch-per-unit-effort data to accurately represent fish population status and trends.
Trends in Abundance and Mean Size of Fish Captured in Gill Nets from Minnesota Lakes, 1983–1997
Authors: Grant Gerold C. , Schwartz Yaniv , Weisberg Sanford , Schupp Dennis H.
Published: June 2004

We investigated seasonal and 15-year trends in catch per unit effort (CPUE) and mean weight of black crappies Pomoxis nigromaculatus, ciscoes Coregonus artedi, northern pike Esox lucius, walleyes Sander vitreus (formerly Stizostedion vitreum), white suckers Catostomus commersoni, and yellow perch Perca flavescens captured in gill nets from 433 Minnesota lakes between 1983 and 1997. Seasonal trends were modeled using least-squares linear and polynomial regressions, and interannual trends were investigated with a linear mixed-effects model and an augmented serially alternating design. Four of the six species exhibited significant seasonal trends. Walleye CPUE increased linearly, whereas walleye and cisco mean weight and northern pike CPUE decreased linearly from spring through fall. Cisco CPUE and yellow perch mean weight exhibited curvilinear relationships, decreasing from spring through summer and then increasing from summer through fall. Two species exhibited significant 15-year trends across Minnesota from 1983 to 1997: Walleyes experienced significant positive trends in both CPUE and mean weight, probably benefiting from more efficient stocking or warmer June temperatures, and black crappies experienced a significant decreasing trend in CPUE, possibly due to replacement by walleyes, loss of spawning habitat, or increased harvest by recreational anglers. Catches of ciscoes, northern pike, white suckers, and yellow perch in gill nets were unchanged across Minnesota between 1983 and 1997, indicating population stability. The results of this study suggest that lakes should be sampled with gill nets at the same time of year or that catches should be corrected to a common date to allow direct comparisons among lakes. The monitoring of trends in fish populations and habitat variables using standardized sampling on broad spatial scales should be more widely used to detect changes, generate hypotheses regarding these changes, and focus research and management efforts.
A Reexamination of the Relationship between Electrofishing Catch Rate and Age-0 Walleye Density in Northern Wisconsin Lakes
Authors: Hansen Michael J. , Newman Steven P. , Edwards Clayton J.
Published: June 2004

We quantified the relationship between the population density (number/acre) of age-0 walleyes Sander vitreus (formerly Stizostedion vitreum) and electrofishing catch per effort (CPE; number/mi) in 19 Wisconsin lakes to update a 1982 analysis by Serns, who used linear regression through the origin to develop a model from a small data set that has been widely used to estimate age-0 walleye density from electrofishing CPE. We added new data, explicitly tested for the linearity of the relationship, and accounted for the effect of measurement errors. We found that electrofishing CPE was nonlinearly related to the population density of age-0 walleyes, which indicated that the catchability of age-0 walleyes to electrofishing declined with population density. The measurement errors in electrofishing CPE were more than nine times as great as those in age-0 walleye population density, so that the parameters of the relationship between electrofishing CPE and age-0 walleye density were accurately estimated by ordinary-least-squares linear regression. Among lakes, the variation in the catchability of age-0 walleyes to electrofishing was positively related to the variation in specific conductivity but not to the variation in other physical features (shoreline complexity or littoral area) or chemical features (alkalinity or pH). Within lakes, the variation in the catchability of age-0 walleyes to electrofishing was negatively related to the variation in temperature at the time of sampling. We recommend that electrofishing CPE only be used as a crude index of age-0 walleye population density.
Ontogenetic Shifts in Habitat and Diet of Cutthroat Trout in Lake Washington, Washington
Authors: Nowak Gretchen M. , Tabor Roger A. , Warner Eric J. , Fresh Kurt L. , Quinn Thomas P.
Published: June 2004

Salmonids often display a series of ontogenetic shifts in habitat, and these may also be associated with changes in diet. For example, adfluvial populations rear in streams for several years and then migrate to lakes. The patterns of habitat use, trophic ecology, and movements of such populations are commonly studied during the riverine stages. The lacustrine period is typically less well known, but salmonids may play an important ecological role as lake piscivores. In Lake Washington, Seattle, Washington, cutthroat trout Oncorhynchus clarki are a top native piscivore and may affect the dynamics of the fish and zooplankton upon which they prey. Our objective was to study the growth, diet, and size distribution of cutthroat trout in littoral and limnetic habitats of Lake Washington, with emphasis on consumption of two of the lake's dominant pelagic planktivores: juvenile sockeye salmon O. nerka and longfin smelt Spirinchus thaleichthys. Cutthroat trout entered the lake at approximately age 2. As they grew larger, the cutthroat trout became increasingly piscivorous and tended to occupy the limnetic zone after they reached about 250 mm fork length (FL). Specifically, percentages (by wet weight) of fish in the diet of cutthroat trout increased from 22.5% for cutthroat trout smaller than 200 mm FL to over 95% for cutthroat trout larger than 400 mm FL. Fish made up a higher percentage of cutthroat trout diets in fall and winter in both the limnetic and littoral zones, and a greater proportion of fish was consumed in the limnetic zone than in the littoral zone. Variation in diet was observed among years (1995–2000), apparently reflecting the relative abundance of longfin smelt. The role of cutthroat trout both as the object of recreational fisheries and as a predator on sockeye salmon (valued in commercial and recreational fisheries) complicates management of this large, urban lake.
Discontinuation of Antihypertensive Drugs Due to Adverse Events: A Systematic Review and Meta‐analysis
Authors: Ross Susan D. , Akhras Kasem S. , Zhang Shuhuan , Rozinsky Michael , Nalysnyk Luba
Published: June 2004

We conducted a systematic review of randomized, controlled, monotherapy trials since 1990 of oral antihypertensive agents in patients with essential hypertension. Our objective was to quantify the frequency of discontinuation of antihypertensive agents due to adverse events from a meta‐analysis of the studies. A total of 190 studies met inclusion criteria. The highest frequency of discontinuations due to adverse events (DAEs) occurred with calcium channel blockers (6.7%) and α‐adrenergic blockers (6.0%); the lowest with diuretics and angiotensin receptor blockers (each 3.1%). Only in calcium channel blocker studies was the frequency of DAEs greater in treated patients than in patients receiving placebo, but the difference was not significant. This systematic review suggests that the frequency of DAEs in monotherapy antihypertensive trials varies across drug classes and should be considered when choosing drugs for patients with essential hypertension.
Rhodococcus equi Pneumonia in a Patient with Human Immunodeficiency Virus: Case Report and Review
Authors: Kwa Andrea L. , Tam Vincent H. , Rybak Michael J.
Published: June 2004

Rhodococcus equi is a facultative, intracellular, gram‐positive coccobacillus increasingly reported as an opportunistic pathogen in patients positive for human immunodeficiency virus (HIV). An HIV‐positive man developed R. equi pneumonia and sepsis. He failed to improve despite surgical drainage of localized infection and many empiric antibiotics. Time‐kill studies of R. equi isolated from the patient were performed against various antimicrobial agents to optimize therapy. Levofloxacin seemed to offer excellent in vitro bactericidal activity. Antagonism was observed with certain antibiotic combinations. Our anecdotal case report suggests that fluoroquinolones such as levofloxacin may offer superior efficacy to standard therapy in rhodococcal infections; their clinical utility deserves further investigation. In view of potential antagonism, prospective susceptibility testing for various drugs and drug combinations should be considered when clinically indicated.
Effect of Triplicate Prescription Policy on Benzodiazepine Administration in Nursing Home Residents
Authors: VanHaaren Anne M. , Lapane Kate L. , Hughes Carmel M.
Published: June 2004

Objective. To estimate the effect of a triplicate prescription policy on administration of benzodiazepines and possible substitute drugs in nursing home residents during 1994–1995.

Design. Retrospective cross‐sectional study.

Setting. Medicare‐ and Medicaid‐certified nursing homes in five states: New York, which has a policy requiring triplicate prescription forms for certain drugs, and four states without such a policy.

Subjects. A total of 211,177 nursing home residents.

Measurements and Main Results. Data were collected using the Minimum Data Set; logistic regression provided an estimated effect of the policy on prescribing benzodiazepines. We also estimated possible substitute drugs for benzodiazepines (e.g., barbiturates, antidepressants, antipsychotics, and miscellaneous sedative‐hypnotics) while adjusting simultaneously for potential confounders. New York nursing home residents were less likely to be receiving benzodiazepine therapy than those in nonpolicy states (odds ratio 0.42; 95% confidence interval 0.41–0.44). No increases occurred in administration of benzodiazepine substitute drugs in New York versus states without a triplicate prescription policy.

Conclusion. Policy did affect prescription and administration of benzodiazepines in nursing homes in states with versus without a triplicate prescription policy. Lack of substitution with other drugs makes it unclear whether overprescribing occurred in states without a policy, or undertreatment occurred in the state with a policy.
An Institution‐Specific Heparin Titration Nomogram: Development, Validation, and Assessment of Compliance
Authors: Sherman Deb S. , Clarke Susan H. , Lefkowitz Jerry B. , Valuck Robert J. , Lindenfeld JoAnn , Stringer Kathleen A.
Published: June 2004

Study Objective. To develop, validate, and assess compliance with a heparin titration nomogram.

Design. Prospective, open‐label trial.

Setting. University teaching hospital.

Subjects. Patients admitted with heart failure who required therapy with intravenous unfractionated heparin.

Intervention. An in vitro concentration‐response was determined by measuring activated partial thromboplastin times (aPTTs) on normal pooled plasma containing known concentrations of heparin. The therapeutic aPTT range was determined from the concentration‐response by using the therapeutic heparin concentration range of 0.2–0.4 U/ml (protamine neutralization). Patients were consecutively enrolled, and therapy was managed by using the heparin titration nomogram. Paired aPTT‐heparin concentrations were obtained, and nomogram validation was performed by comparing the in vitro and the ex vivo concentration‐responses with use of linear regression. Nomogram compliance also was assessed.

Measurements and Main Results. The therapeutic aPTT ranges based on in vitro and ex vivo data were determined to be 45–72 seconds and 47–61 seconds, respectively. The ranges were significantly different (p<0.001). Overall compliance with the nomogram was 88%.

Conclusion. These results confirm that, even in a relatively homogeneous disease‐state patient population, in vitro data do not accurately predict ex vivo data. If in vitro data are used to develop an institution‐specific nomogram, a validation procedure should be used to ensure accuracy. Although 100% compliance to a nomogram may not be attainable, it should be expected. Therefore, a compliance rate of 88% is concerning and suggests a need for increased nursing and physician education.
Efficacy of Metoclopramide in Postoperative Ileus after Exploratory Laparotomy
Authors: Seta Maria L. , Kale‐Pradhan Pramodini B.
Published: June 2004

Study Objective. To assess the efficacy of metoclopramide for treatment of postoperative ileus in patients who underwent exploratory laparatomy.

Design. Prospective observational study.

Setting. Surgical intensive care unit (SICU).

Patients. Thirty‐two patients who underwent exploratory laparatomy.

Intervention. Sixteen patients received metoclopramide, and 16 did not. The primary outcome was time to first postoperative bowel movement. Secondary end points were length of stay (LOS) in the SICU and total hospital LOS.

Measurements and Main Results. The mean number of days to first bowel movement was nearly identical for both the treatment group and control group (4.8 vs 4.7 days, respectively, p=0.93). Length of stay in the SICU was 8.3 days for the treatment group and 8.6 days for the control group (p=0.89), and total LOS was 18.0 and 20.1 days, respectively (p=0.63).

Conclusion. The time to first bowel movement was not significantly different between the treatment and control groups. Also, metoclopramide did not decrease LOS. Metoclopramide does not have a role in the treatment of postoperative ileus.