bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic Basis of Multidrug Resistance in
Acinetobacter baumannii
Clinical Isolates at a Tertiary Medical Center in Pennsylvania
Authors: Adams-Haduch Jennifer M. , Paterson David L. , Sidjabat Hanna E. , Pasculle Anthony W. , Potoski Brian A. , Muto Carlene A. , Harrison Lee H. , Doi Yohei
Published: August 2008

A total of 49 unique clinical isolates of multidrug-resistant (MDR)
Acinetobacter baumannii
identified at a tertiary medical center in Pittsburgh, Pennsylvania, between August 2006 and September 2007 were studied for the genetic basis of their MDR phenotype. Approximately half of all
A. baumannii
clinical isolates identified during this period qualified as MDR, defined by nonsusceptibility to three or more of the antimicrobials routinely tested in the clinical microbiology laboratory. Among the MDR isolates, 18.4% were resistant to imipenem. The frequencies of resistance to amikacin and ciprofloxacin were high at 36.7% and 95.9%, respectively. None of the isolates was resistant to colistin or tigecycline. The presence of the carbapenemase gene
bla
OXA-23
and the 16S rRNA methylase gene
armA
predicted high-level resistance to imipenem and amikacin, respectively.
bla
OXA-23
was preceded by insertion sequence IS
Aba1
, which likely provided a potent promoter activity for the expression of the carbapenemase gene. The structure of the transposon defined by IS
Aba1
differed from those reported in Europe, suggesting that IS
Aba1
-mediated acquisition of
bla
OXA-23
may occur as an independent event. Typical substitutions in the quinolone resistance-determining regions of the
gyrA
and
parC
genes were observed in the ciprofloxacin-resistant isolates. Plasmid-mediated quinolone resistance genes, including the
qnr
genes, were not identified. Fifty-nine percent of the MDR isolates belonged to a single clonal group over the course of the study period, as demonstrated by pulsed-field gel electrophoresis.
In Vitro Activities of Tigecycline and 10 Other Antimicrobials against Nonpigmented Rapidly Growing Mycobacteria
Authors: Fernández-Roblas R. , Martín-de-Hijas N. Z. , Fernández-Martínez A. I. , García-Almeida D. , Gadea I. , Esteban J.
Published: August 2008

We evaluated the in vitro activities of tigecycline and 10 other antibiotics against clinical isolates of nonpigmented rapidly growing mycobacteria. Fifteen collection strains and 165 clinical isolates were included in the study. Tigecycline showed the highest activity among all antibiotics studied: all the strains were inhibited by 1 mg/liter.
Oseltamivir-Ribavirin Combination Therapy for Highly Pathogenic H5N1 Influenza Virus Infection in Mice
Authors: Ilyushina Natalia A. , Hay Alan , Yilmaz Neziha , Boon Adrianus C. M. , Webster Robert G. , Govorkova Elena A.
Published: August 2008

We studied the effects of a neuraminidase inhibitor (oseltamivir) and an inhibitor of influenza virus polymerases (ribavirin) against two highly pathogenic H5N1 influenza viruses. In vitro, A/Vietnam/1203/04 virus (clade 1) was highly susceptible to oseltamivir carboxylate (50% inhibitory concentration [IC50] = 0.3 nM), whereas A/Turkey/15/06 virus (clade 2.2) had reduced susceptibility (IC50= 5.5 nM). In vivo, BALB/c mice were treated with oseltamivir (1, 10, 50, or 100 mg/kg of body weight/day), ribavirin (37.5, 55, or 75 mg/kg/day), or the combination of both drugs for 8 days, starting 4 h before virus inoculation. Monotherapy produced a dose-dependent antiviral effect against the two H5N1 viruses in vivo. Three-dimensional analysis of the drug-drug interactions revealed that oseltamivir and ribavirin interacted principally in an additive manner, with several exceptions of marginal synergy or marginal antagonism at some concentrations. The combination of ribavirin at 37.5 mg/kg/day and oseltamivir at 1 mg/kg/day and the combination of ribavirin at 37.5 mg/kg/day and oseltamivir at 10 mg/kg/day were synergistic against A/Vietnam/1203/04 and A/Turkey/15/06 viruses, respectively. These optimal oseltamivir-ribavirin combinations significantly inhibited virus replication in mouse organs, prevented the spread of H5N1 viruses beyond the respiratory tract, and abrogated the cytokine response (P< 0.01). Importantly, we observed clear differences between the efficacies of the drug combinations against two H5N1 viruses: higher doses were required for the protection of mice against A/Turkey/15/06 virus than for the protection of mice against A/Vietnam/1203/04 virus. Our preliminary results suggest that oseltamivir-ribavirin combinations can have a greater or lesser antiviral effect than monotherapy, depending on the H5N1 virus and the concentrations used.
ZapA, a Virulence Factor in a Rat Model of
Proteus mirabilis
-Induced Acute and Chronic Prostatitis
Authors: Phan Van , Belas Robert , Gilmore Brendan F. , Ceri Howard
Published: August 2008

Our knowledge of pathogenesis has benefited from a better understanding of the roles of specific virulence factors in disease. To determine the role of the virulence factor ZapA, a 54-kDa metalloproteinase of
Proteus mirabilis
, in prostatitis, rats were infected with either wild-type (WT)
P. mirabilis
or its isogenic ZapA
−
mutant KW360. The WT produced both acute and chronic prostatitis showing the typical histological progressions that are the hallmarks of these diseases. Infection with the ZapA
−
mutant, however, resulted in reduced levels of acute prostatitis, as determined from lower levels of tissue damage, bacterial colonization, and inflammation. Further, the ZapA
−
mutant failed to establish a chronic infection, in that bacteria were cleared from the prostate, inflammation was resolved, and tissue was seen to be healing. Clearance from the prostate was not the result of a reduced capacity of the ZapA
−
mutant to form biofilms in vitro. These finding clearly define ZapA as an important virulence factor in both acute and chronic bacterial prostatitis.
The Interaction of
Streptococcus pneumoniae
with Plasmin Mediates Transmigration across Endothelial and Epithelial Monolayers by Intercellular Junction Cleavage
Authors: Attali Cécile , Durmort Claire , Vernet Thierry , Di Guilmi Anne Marie
Published: August 2008

The precise mechanisms by which
Streptococcus pneumoniae
overcomes epithelial and endothelial barriers to access underlying human tissues remain to be determined. The plasminogen system is highly important for the tissue barrier degradation which allows cell migration. Plasminogen is known to interact with pneumococci via enolase, glyceraldehyde-3-phosphate dehydrogenase, and choline-binding protein E. These observations prompted us to evaluate the role of this proteolytic system in the pneumococcal invasion process. We observed that coating of
S. pneumoniae
R6 strain with plasminogen or inactivated plasmin increased adherence to pulmonary epithelial A549 and vascular endothelial EaHy cells in vitro. This indicates that plasminogen-mediated adherence is independent of the protease activity and involves plasminogen binding to receptors on eukaryotic cell surfaces. Conversely, decreased adherence of bacterial cells coated with active plasmin was observed, indicating that the protease activity limits bacterial attachment on the cell surface. We were then interested in investigating the role of the proteolytic plasmin activity in the traversal of tissue barriers. We observed that adherence of plasmin-coated D39 (encapsulated) or R6 (unencapsulated) pneumococci induced sporadic disruptions of EaHy and A549 monolayer cell junctions. This was not observed when plasmin was inhibited by aprotinin. Endothelial junction disorganization may proceed by proteolysis of the cell junction components. This is supported by our observation of the in vitro cleavage by plasmin bound to pneumococci of recombinant vascular endothelial cadherin, the main component of endothelial adherens junctions. Finally, junction damage induced by plasmin may be related to tissue barrier traversal, as we measured an increase of
S. pneumoniae
transmigration across epithelial A549 and endothelial EaHy layers when active plasmin was present on the bacterial surface. Our results highlight a novel function for the plasminogen recruitment at the bacterial surface in facilitating adherence of pneumococci to endothelial and epithelial cells, while active plasmin degrades intercellular junctions. This process promotes migration of pneumococci through cell barriers by a pericellular route, a prerequisite for dissemination of
S. pneumoniae
in the host organism.
Temporal Delay of Peak T-Cell Immunity DeterminesChlamydia pneumoniaePulmonary Disease in Mice
Authors: Wang Chengming , van Ginkel Frederik W. , Kim Teayoun , Li Dan , Li Yihang , Dennis John C. , Kaltenboeck Bernhard
Published: August 2008

Severe chlamydial disease typically occurs after previous infections and results from a hypersensitivity response that is also required for chlamydial elimination. Here, we quantitatively dissected the immune and disease responses to repeatedChlamydia pneumoniaelung infection by multivariate modeling with four dichotomous effects: mouse strain (A/J or C57BL/6), dietary protein content (14% protein and 0.3%l-cysteine-0.9%l-arginine, or 24% protein and 0.5%l-cysteine-2.0%l-arginine), dietary antioxidant content (90 IU α-tocopherol/kg body weight versus 450 IU α-tocopherol/kg and 0.1% gl-ascorbate), and time course (3 or 10 days postinfection). Following intranasalC. pneumoniaechallenge, C57BL/6 mice on a low-protein/low-antioxidant diet, but not C57BL/6 mice on other diets or A/J mice, exhibited profoundly suppressed early lung inflammatory and pan-T-cell (CD3δ+) and helper T-cell (CD45) responses on day 3 but later strongly exacerbated disease on day 10. Contrast analyses characterized severeC. pneumoniaedisease as being a delayed-type hypersensitivity (DTH) response with increased lung macrophage and Th1 cell marker transcripts, increased Th1:Th2 ratios, and Th1 cytokine-driven inflammation. Results from functional analyses by DTH, enzyme-linked immunospot, and immunohistofluorescence assays were consistent with the results obtained by transcript analysis. Thus, chlamydial disease after secondary infection is a temporal dysregulation of the T-cell response characterized by a profoundly delayed T-helper cell response that results in a failure to eliminate the pathogen and provokes later pathological Th1 inflammation. This delayed T-cell response is under host genetic control and nutritional influence. The mechanism that temporally and quantitatively regulates the host T-cell population is the critical determinant in chlamydial pathogenesis.
Inequalities and healthcare reform in Chile: equity of what?
Authors: Burrows J
Published: August 2008

Chile has achieved great success in terms of growth and development. However, growing inequalities exist in relation to income and health status. The previous Chilean government began to reform the healthcare system with the aim of reducing health inequities. What is meant by “equity” in this context? What is the extent of the equity aimed for? A normative framework is required for public policy-makers to consider ideas about fairness in their decisions about healthcare reform. This paper aims to discuss the main features of the Chilean healthcare reform and their implications for such a normative framework.
Empirical Prediction of Fish Biomass and Yield
Authors: Hanson John Mark , Leggett William C.
Published: August 2008

Data taken from the literature were used to develop and compare predictors of fish biomass and yield in lakes. Two new indices, total phosphorus concentration and macrobenthos biomass/mean depth, were the best univariate predictors offish yield (r2 = 0.84 and r2 = 0.48, respectively) and biomass (r2 = 0.75 and r2 = 0.83, respectively) for four different data sets. Both new indices were stronger predictors of fish yield when compared to the morphoedaphic index, total dissolved solids, or mean depth for the same data set. The relatively constant relationship between fish biomass and macrobenthos biomass/mean depth implies a near-constant energy transfer from the benthos to the fish regardless of the number of fish species present.Key words: biomass, yield, fish, macrobenthos, phosphorus, depth, dissolved solids, morphoedaphic index, lakes
Histology and Prevalence of X-Cell Lesions in Atlantic Cod (Gadus morhua)
Authors: Morrison C. M. , Shum G. , Appy R. G. , Odense P. , Annand C.
Published: August 2008

The prevalence of X-cell lesions in Atlantic cod (Gadus morhua) from the Canadian Atlantic was similar to that in German Bight and lower than their prevalence in G. macrocephalus off the west coast of Canada. The lesions, which are now believed to be xenomas composed of X-cell parasites and host cells were different from those described by other authors in that the pseudobranchs could always be seen on the exposed surface of the lesion, and were not infiltrated by X-cells. Sometimes the X-cell lesion was separate from the pseudobranch. Most of the X-cells in the lesion appeared to be degenerate, but areas of normal X-cells with distinctive features could always be found. No phagocytes were seen in the X-cell lesion, although a cellular host reaction to microsporidian and other parasites was often seen in and around the pseudobranch. It is suggested that the envelope cells, which are fibroblast-like, may represent a host response to the X-cells.Key words: pseudobranch tumor, X-cells, Atlantic cod, Gadus morhua, Canadian Atlantic, epizootiology, histology, ultrastructure
Pu Residence Times in Freshwaters and Accumulation in Shield Lake Sediments
Authors: Cornett R. J. , Chant L.
Published: August 2008

Activity balances for 239,240Pu in seven oligotrophic lakes were constructed from measurements of 239,240Pu inputs and measurements of 239,240Pu accumulated in the lake sediments. 239,240Pu eroded from the catchment was a significant input to lakes with rapid hydrologic flushing rates. From 28 to 100% of the 239,240Pu input to the lakes accumulated in the lake sediments. The fraction of 239,240Pu inputs accumulated in the lake sediments was inversely correlated with the hydrologic flushing rate of the lake. 239,240Pu concentrations in the sediments were simulated using a single reservoir input–output model. Partial residence times for 239,240Pu transfer from the water to the sediments ranged from 0.09 to 2.7 yr and were shorter in lakes with more rapid flushing. Partial residence times of 239,240Pu in these small shield lakes were very similar to the residence times of 239,240Pu in the Laurentian Great Lakes and to those of 137Cs and 210Pb in other small oligotrophic lakes.
Uncertainty in Stock Composition Estimates of Oceanic Steelhead Trout Using Electrophoretic Characteristics: Comments on a Recent Study
Authors: Mulligan T. J. , McKinnell S. , Wood C. C.
Published: August 2008

Analysis of stock composition of mixed-stock fisheries using electrophoretic data is gaining acceptance for both research and management purposes. However, a thorough understanding of the influence of sample size, stock separation, and estimation procedures is required before meaningful results can be obtained. An example from the recent literature is reanalyzed to demonstrate this conclusion. We show how widely different results are obtained from the same data when analyzed by two different models. Some insight into these differences is achieved through a Monte Carlo simulation study.
Intrapopulation Variation of the Esterase-2 Polymorphism in the Serum of Anadromous Arctic Charr, Salvelinus alpinus, from a Northern Labrador River
Authors: Dempson J. B. , Verspoor E. , Hammar J.
Published: August 2008

Intrapopulation variation of the diallelic Esterase-2 (serum esterase) polymorphism in the Arctic charr, Salvelinus alpinus, was studied in an anadromous population from the Ikarut River in northern Labrador. Differences in genotype frequencies observed between two sampling years, between sexes, and between juvenile and mature fish were not significant. However, considerable variation was found in the allele frequencies among year-classes. Furthermore, the allele frequency variation was associated with temperature; the frequency of the fast allele, F, was positively correlated with the mean summer temperatures in the year of hatching. The same type of association has been found in a Swedish population. Temperature-dependent selection in late incubation or post-hatching in the fry or fingerling stage could explain the observed association. The nonrandom distribution of the variation within populations has important implications for the use of the polymorphism in stock discrimination work and for the interpretation of interpopulation variation.
Migration of Postsmolt Atlantic Salmon, Salmo salar, Off Northeastern Newfoundland, As Inferred by Tag Recoveries in a Seabird Colony
Authors: Montevecchi W. A. , Cairns D. K. , Birt V. L.
Published: August 2008

Northern gannets, Sula bassanus, and possibly other seabird species nesting on Funk Island off northeastern Newfoundland preyed on postsmolt Atlantic salmon, Salmo salar. Salmon comprised less than 1% of 2928 regurgitated food samples collected from gannets at the colony. Ten smolt tags were recovered in and near the gannetry during August or September in 1984 through 1986. The tags were from smolts released 3–4 mo earlier in the Penobscot River (Maine) (n = 7) and one each from the Saint John River (New Brunswick) and the Lower Clyde and LaHave rivers (Nova Scotia). These recoveries provide evidence that postsmolt Atlantic salmon from rivers in New England, the Bay of Fundy, and the Atlantic coast of Nova Scotia migrate off eastern Newfoundland This migratory pattern contrasts with that of postsmolts from the Gulf of St. Lawrence, which tend to move northwards along Newfoundland's west coast and through the Strait of Belle Isle.
Lack of Response of Channel Catfish (Ictalurus punctatus) to Dietary Myo-inositol
Authors: Burtle G. J. , Lovell R. T.
Published: August 2008

Channel catfish (Ictalurus punctatus) fingerlings were fed for 28 wk in aquaria (28 ± 1 °C) on semipurified diets with supplemental myo-inositol (400 mg∙kg diet−1), without myo-inositol, and without myo-inositol but with succinylsulfathiazole to suppress intestinal bacteria synthesis. Omission of myo-inositol from the diet, with or without the antibiotic, did not reduce growth rate, produce overt signs of myo-inositol deficiency, or cause a decrease in tissue (muscle, liver, and brain) concentration of myo-inositol. No lipid accumulation occurred in liver or kidney when myoinositol was deleted from the diet. The only possible lipotropic effect of myo-inositol deficiency was a slightly higher (P < 0.07) amount of lipid in brain tissue. Myo-inositol synthesis by enzymes in liver and brain tissues was not affected by myo-inositol in the diet. Rates of myo-inositol synthesis were 39.8 and 67.3 μmol∙h−1∙g protein−1 for liver and brain, which are higher than synthesis rates reported in rodents (myo-inositol synthesis has not been measured in other fish). This study showed that de novo synthesis of myo-inositol by fingerling channel catfish was sufficient for normal growth and maintenance of tissue levels of myo-inositol and to prevent overt signs of myo-inositol deficiency when the vitamin was not included in the diet.
Offshore Distribution, Size, Age, and Lateral Plate Variation of Late Larval/Early Juvenile Sticklebacks (Gasterosteus) off the Atlantic Coast of New Jersey and New York
Authors: Cowen Robert K. , Chiarella Louis A. , Gomez Candice J. , Bell Michael A.
Published: August 2008

Late larval and early juvenile sticklebacks, Gasterosteus aculeatus (14–28 mm SL) and G. wheatlandi (11–19 mm SL), were collected over shelf waters in the New York Bight during May, June, and July 1988. Gasterosteus aculeatus occurred up to 110 km offshore, with peak abundances found from 3 to 75 km. Gasterosteus wheatlandi was most prevalent within 10 km of shore, but some individuals were collected up to 55 km offshore. The further offshore distribution of G. aculeatus should increase its potential for dispersal, perhaps explaining their capacity to found freshwater populations in recently deglaciated habitats. The relatively nearshore distribution of G. wheatlandi should minimize dispersal (especially around Cape Cod) and may maintain a distinct, morphological step cline by the relative isolation of two subpopulations above and below Cape Cod.
Variation in the relationship between otolith weight and age: implications for the estimation of age of two tropical damselfish (Pomacentrus moluccensis and P. wardi)
Authors: Worthington D. O. , Doherty P. J. , Fowler A. J.
Published: August 2008

The weight of otoliths may provide an objective and economic method of ageing fish. To investigate this potential, populations of two species of fish (Pomacentrus moluccensis and P. wardi) were sampled from the lagoons of seven coral reefs within the Great Barrier Reef, Australia. The weight of otoliths increased with age throughout the life of both species. Two factors appeared to have the potential to undermine the use of otolith weight to estimate the age of individuals. First, overlap in the range of otolith weight among fish of different ages caused normally distributed errors in the subsequent estimation of age by otolith weight. Second, variation among reefs in the relationship between otolith weight and age biased subsequent age determinations. Both these types of error also affected the estimation of the age structure of the populations. Random errors in age determination resulted in the smoothing of the age structure whilst bias either shifted or compressed the age structure. While smoothing of an age structure will not compromise the results of several types of analysis, bias will be detrimental to most. Consequently, randomization methods were used to estimate the power of tests to detect variation in the relationship between otolith weight and age. Our results show that by frequently recalibrating the relationship between otolith weight and age, it can be used as an objective and economic method of age determination with the potential to be as reliable as counting annuli in sectioned otoliths.
Trapping interactions of crabs and American lobster in laboratory tanks
Authors: Miller R. J. , Addison J. T.
Published: August 2008

The relationship between trap catches of decapods and their abundance is not well established. Because it is difficult to manipulate density in the field, laboratory tanks were used to examine 10 hypotheses about the intra- and interspecific interactions of rock crab (Cancer irroratus), green crab (Carcinus maenas), and American lobster (Homarus americanus). The proportion of rock crabs captured did not differ among high, medium, and low densities, but the proportion captured was reduced at high densities for both green crabs and lobsters. Additional experiments demonstrated that large green and rock crabs in the tanks reduced the catch of small green and rock crabs and that the presence of lobsters reduced the catch of both crab species considerably. However, small rock crabs did not reduce the catch of large rock crabs, and neither green nor rock crabs reduced the catch of each other. Reductions in the catch of a target species caused by interactions in the field can perhaps be lessened by removing the catch from the trap at intervals of less than 24 h. Then the catches would be summed over 24 h for an index of abundance.
Relating trends in walleye pollock (Theragra chalcogramma) abundance in the Bering Sea to environmental factors
Authors: Swartzman Gordon , Silverman Emily , Williamson Neal
Published: August 2008

Generalized additive models (GAM), a nonparametric regression method with less restrictive statistical assumptions than traditional regression methods, were used to model the trend in mean abundance of Bering Sea walleye pollock (Theragra chalcogramma) as a function of ocean environmental conditions including water column depth, temperature at 50 m, and depth of the thermocline. Acoustic survey data collected in the summers of 1988 and 1991 were used to test these relationships. In both surveys, mean walleye pollock abundance was highest in areas having a 70–130 m depth range and where the 50-m temperature was close to 2.5 °C. Thermocline depth, while not itself significant, had a significant effect on walleye pollock abundance through interactions with both bottom depth and temperature at 50 m. Walleye pollock in the top 50 m of the water column (mostly juveniles) were influenced differently by temperature and thermocline depth than the adult walleye pollock, which were generally deeper in the water column. The depth, temperature, and thermocline preferences of walleye pollock are hypothesized to be linked to food availability which is, in turn, related to temperature regimes or fronts along the Bering Sea shelf slope.
Fish production in freshwaters: Are rivers more productive than lakes?
Authors: Randall R. G. , Minns C. K. , Kelso J. R. M.
Published: August 2008

Community fish production data were summarized from the literature to test the hypothesis that production is higher in rivers than in lakes. Average community production at 55 river sites was three times greater (273 kg∙ha−1∙year−1) than at 22 lakes (82 kg∙ha−1∙year−1). Higher production (P) in rivers resulted from much higher densities of fish (14 times) and greater biomass (B) (about 2 times). Average fish weight and P/B ratios were inversely correlated. Average fish weight was 7 times less, and P/B ratios were 1.5 times higher (after correction for fish size), in rivers than in lakes. Thus, rivers not only had higher average biomasses of fish but also the turnover rate of the biomass was greater. Fish production was positively correlated with phosphorus in both lakes and rivers. Information on community fish production supported the hypothesis that the productivity of river habitat is, on average, higher than the productivity of lake habitat. The productive capacity of freshwater habitats can be predicted using a multiple regression model developed by Boudreau and Dickie (Can. J. Fish. Aquat. Sci. 46: 614. 1989), where fish production is calculated from average fish biomass and body mass.
Mixed-stock analysis of striped bass in two rivers of the Bay of Fundy as revealed by mitochondrial DMA
Authors: Wirgin Isaac , Pedersen Mark , Maceda Steven , Jessop Brian , Courtenay Simon , Waldman John R.
Published: August 2008

Mark–recapture studies have shown that striped bass from the Hudson River and Chesapeake Bay migrate to the Bay of Fundy and its tributaries during spring and summer. The objective of this study was to determine the relative contributions of U.S. stocks and the endemic Shubenacadie River population to the adult striped bass aggregations that occurred during 1992 and 1993 in two rivers of the Bay of Fundy: the Saint John River, New Brunswick (where striped bass spawning may not presently occur), and the Shubenacadie River, Nova Scotia (where striped bass spawning occurs). Mitochondrial DNA genotype frequency data were used in a mixture model. Up to 97% of adults from the Saint John River were determined to be of U.S. origin, whereas less than 10% of adult striped bass collected in the Shubenacadie River were migrants from U.S. stocks. Consequently, we suggest that efforts to maintain or restore the Saint John River population with native broodstock may be unsuccessful owing to possible extinction of the native stock; however, protection of the Shubenacadie River spawning stock should be enhanced.
A robust regression analysis of recruitment in fisheries
Authors: Chen Y. , Paloheimo J. E.
Published: August 2008

Variations in environmental variables and (or) errors in measuring stock and recruitment often result in large and heterogeneous variations in fitting fish stock–recruitment (SR) data to a regression model. This makes the commonly used least squares (LS) method inappropriate in estimating the SR relationship. Hence, we propose the following procedure: (i) identify possible outliers in fitting data to a given SR model using the least median of the squared orthogonal distance that is not sensitive to atypical values and requires no assumption on distribution of errors and (ii) apply the LS method to the SR data with defined outliers being down weighted. We showed by simulation that the SR parameters of the Ricker model could be estimated with smaller estimation errors and biases using the proposed procedures than with the traditional LS approach. Examination of four sets of published field data leads us to suggest fitting fish SR data to suitable models using the proposed estimation method and interpreting the results with the assistance of knowledge on the relevant environmental variables and measurement errors. However, our interpretation should be viewed as a working hypothesis requiring special studies to clarify the causal links between environmental variables and recruitment.
Pulmonary fibrosis in l-NAME-treated mice is dependent on an activated endothelin systemThis article is one of a selection of papers published in the special issue (part 2 of 2) on Forefronts in Endothelin.
Authors: Kalk Philipp , Mach Alexander , Thone-Reineke Christa , Godes Michael , Heiden Susi , Sharkovska Yuliya , von Websky Karoline , Relle Katharina , Hocher Berthold
Published: August 2008

Activation of the endothelin (ET) system promotes vasoconstriction, inflammation, and fibrosis in various tissues, including the lung. Therefore, ET-1 transgenic mice overexpressing ET-1 develop pulmonary fibrosis in a slow, age-dependent manner. In vivo, NO is the most important counterregulatory mediator of the ET system and decreases ET-1 promoter activity. The aim of our study was to elucidate the impact on pulmonary inflammation and fibrosis of the interaction between NO and the ET system in young ET-1 transgenic mice before the onset of pulmonary fibrosis. Male ET-1 transgenic mice and wild-type littermates at the age of 8 weeks were randomly allocated to the following 6 groups: WT (n = 11), wild-type animals without treatment; WT + l-NAME (n = 14), wild-type animals receiving l-NAME, an inhibitor of NO synthase; WT + l-NAME + LU (n = 13), wild-type animals receiving l-NAME and LU 302872, a dual ETA/ETB-receptor antagonist; ET1tg (n = 10), ET-1 transgenic mice; ET1tg + l-NAME (n = 13); and ET1tg + l-NAME + LU (n = 13). After 6 weeks, animals were euthanized, and hearts and lungs were harvested for histology and immunohistochemistry. No differences in pulmonary inflammation, as indicated by macrophage infiltration, or in interstitial fibrosis were observed between WT and ET1tg mice at baseline; however, inflammation and interstitial fibrosis were significantly enhanced in ET1tg mice, but not in WT groups, after l-NAME treatment. The combined ETA/ETB-receptor antagonist LU 302872 abolished inflammation and interstitial fibrosis in l-NAME-treated ET1tg mice. Perivascular fibrosis and media/lumen ratio of pulmonary bronchi and arteries did not differ between all study groups. In our study l-NAME induced pulmonary fibrosis and inflammation only in young ET1tg mice. Additional treatment with LU 302872 abolished these effects. We thus conclude that an imbalance between an activated ET system and a suppressed NO system contributes to pulmonary inflammation and fibrosis.
Morphological Integration and Developmental Modularity
Authors: Klingenberg Christian Peter
Published: August 2008

Biological systems, from molecular complexes to whole organisms and ecological interactions, tend to have a modular organization. Modules are sets of traits that are internally integrated by interactions among traits, but are relatively independent from other modules. The interactions within modules rely on different mechanisms, depending on the context of a study. For morphological traits, modularity occurs in developmental, genetic, functional, and evolutionary contexts. A range of methods for quantifying integration and modularity in morphological data is available, and a number of comparative and experimental designs can be used to compare the different contexts. How development produces covariation between traits can have substantial implications for understanding genetic variation and the potential for evolutionary change, but research in this area has only begun and many questions remain unanswered.
The Treatment of Hyperhomocysteinemia
Authors: Maron Bradley A. , Loscalzo Joseph
Published: August 2008

The unique biochemical profile of homocysteine is characterized by chemical reactivity supporting a wide range of molecular effects and by a tendency to promote oxidant stress–induced cellular toxicity. Numerous epidemiological reports have established hyperhomocysteinemia as an independent risk factor for cardiovascular disease, cerebrovascular disease, dementia-type disorders, and osteoporosis-associated fractures. Although combined folic acid and B-vitamin therapy substantially reduces homocysteine levels, results from randomized placebo-controlled clinical trials testing the effect of vitamin therapy on outcome in these diseases have generally fallen short of expectations. These results have led some to abandon homocysteine monitoring in the management of patients with cardiovascular or cognitive disorders. These trials, however, have generally included patients with only mildly elevated homocysteine levels and have not addressed several clinical scenarios in which homocysteine reduction may be effective, including the primary prevention of atherothrombotic disease in individuals at low or intermediate risk, or those with severe hyperhomocysteinemia.
Food Allergy: Recent Advances in Pathophysiology and Treatment
Authors: Sicherer Scott H. , Sampson Hugh A.
Published: August 2008

Food allergies, defined as an adverse immune response to food proteins, affect as many as 6% of young children and 3%–4% of adults in westernized countries, and their prevalence appears to be rising. In addition to well-recognized acute allergic reactions and anaphylaxis triggered by IgE antibody–mediated immune responses to food proteins, there is an increasing recognition of cell-mediated disorders such as eosinophilic gastroenteropathies and food protein–induced enterocolitis syndrome. We are gaining an increasing understanding of the pathophysiology of food allergic disorders and are beginning to comprehend how these result from a failure to establish or maintain normal oral tolerance. Many food allergens have been characterized at a molecular level, and this knowledge, combined with an increasing appreciation of the nature of humoral and cellular immune responses resulting in allergy or tolerance, is leading to novel therapeutic approaches. Currently, management of food allergies consists of educating the patient to avoid ingesting the responsible allergen and initiating therapy if ingestion occurs. However, numerous strategies for definitive treatment are being studied, including sublingual/oral immunotherapy, injection of anti-IgE antibodies, cytokine/anticytokine therapies, Chinese herbal therapies, and novel immunotherapies utilizing engineered proteins and strategic immunomodulators.
Goals of Inpatient Treatment for Psychiatric Disorders
Authors: Sharfstein Steven S.
Published: August 2008

The purpose of the psychiatric hospital changed dramatically during the twentieth century. Formerly the primary location for psychiatric treatment, the hospital now plays a more circumscribed role within a community-based system of care. Crisis stabilization, safety, and a focus on rapid discharge are the critical components of the acute inpatient stay. Subspecialized units focus on geriatrics, children, adolescents, dual diagnosis (substance abuse and mental illness), trauma disorders, eating disorders, and forensics. When integrated with the general medical system and a comprehensive base of community-delivered day treatment, residential sevices, and outpatient services, psychiatric hospitalization is a humane alternative to long-term institutional care.
Molecular Pathology of Head and Neck Cancer: Implications for Diagnosis, Prognosis, and Treatment
Authors: Pai Sara I. , Westra William H.
Published: August 2008

The prototypic head and neck squamous cell carcinoma (HNSCC) arises from the mucosal lining of the upper aerodigestive tract, demonstrates squamous differentiation microscopically, involves older men with a long history of cigarette smoking and alcohol consumption, and is treated by multimodality therapy. HNSCC has long been regarded as a uniform disease process requiring a methodical and unwavering therapeutic approach. Divergence in epidemiologic trends among HNSCCs arising from different anatomic sites has introduced a view that, morphologic repetition aside, head and neck cancers form a heterogeneous group. This view has been supported at the molecular genetic level. A more complete understanding of the molecular genetics of head and neck cancer is providing new insights into long-held but poorly comprehended concepts such as field cancerization and is introducing various biomarkers with potential application for diagnosing, staging, monitoring, and prognosticating HNSCC.
Emotion Theory and Research: Highlights, Unanswered Questions, and Emerging Issues
Authors: Izard Carroll E.
Published: August 2008

Emotion feeling is a phase of neurobiological activity, the key component of emotions and emotion-cognition interactions. Emotion schemas, the most frequently occurring emotion experiences, are dynamic emotion-cognition interactions that may consist of momentary/situational responding or enduring traits of personality that emerge over developmental time. Emotions play a critical role in the evolution of consciousness and the operations of all mental processes. Types of emotion relate differentially to types or levels of consciousness. Unbridled imagination and the ability for sympathetic regulation of empathy may represent both potential gains and losses from the evolution and ontogeny of emotion processes and consciousness. Unresolved issues include psychology's neglect of levels of consciousness that are distinct from access or reflective consciousness and use of the term “unconscious mind” as a dumpster for all mental processes that are considered unreportable. The relation of memes and the mirror neuron system to empathy, sympathy, and cultural influences on the development of socioemotional skills are unresolved issues destined to attract future research.
Genomic expression analysis of rat chromosome 4 for skeletal traits at femoral neck
Authors: Alam Imranul , Sun Qiwei , Liu Lixiang , Koller Daniel L. , Liu Yunlong , Edenberg Howard J. , Econs Michael J. , Foroud Tatiana , Turner Charles H.
Published: August 2008

Hip fracture is the most devastating osteoporotic fracture type with significant morbidity and mortality. Several studies in humans and animal models identified chromosomal regions linked to hip size and bone mass. Previously, we identified that the region of 4q21-q41 on rat chromosome (Chr) 4 harbors multiple femoral neck quantitative trait loci (QTLs) in inbred Fischer 344 (F344) and Lewis (LEW) rats. The purpose of this study is to identify the candidate genes for femoral neck structure and density by correlating gene expression in the proximal femur with the femoral neck phenotypes linked to the QTLs on Chr 4. RNA was extracted from proximal femora of 4-wk-old rats from F344 and LEW strains, and two other strains, Copenhagen 2331 and Dark Agouti, were used as a negative control. Microarray analysis was performed using Affymetrix Rat Genome 230 2.0 arrays. A total of 99 genes in the 4q21-q41 region were differentially expressed ( P < 0.05) among all strains of rats with a false discovery rate <10%. These 99 genes were then ranked based on the strength of correlation between femoral neck phenotypes measured in F2 animals, homozygous for a particular strain's allele at the Chr 4 QTL and the expression level of the gene in that strain. A total of 18 candidate genes were strongly correlated (r2 > 0.50) with femoral neck width and prioritized for further analysis. Quantitative PCR analysis confirmed 14 of 18 of the candidate genes. Ingenuity pathway analysis revealed several direct or indirect relationships among the candidate genes related to angiogenesis (VEGF), bone growth (FGF2), bone formation (IGF2 and IGF2BP3), and resorption (TNF). This study provides a shortened list of genetic determinants of skeletal traits at the hip and may lead to novel approaches for prevention and treatment of hip fracture.
Electro‐Optical and Electrochemical Properties of a Conjugated Polymer Prepared by the Cyclopolymerization of Diethyl Dipropargylmalonate
Authors: Gal Yeong-Soon , Lee Won-Chul , Lyoo Won Seok , Jin Sung-Ho , Lim Kwon Taek , Park Young-Il , Park Jong-Wook
Published: August 2008

The electro‐optical and electrochemical properties of poly(diethyl dipropargylmalonate) were measured and discussed. Poly(diethyl dipropargylmalonate) prepared by (NBD)PdCl2 catalyst was used for study. The chemical structure of poly(diethyl dipropargylmalonate) was characterized by such instrumental methods as NMR ( 1H‐,  13C‐), IR, and UV‐visible spectroscopies to have the conjugated cyclopolymer backbone system. The microstructure analysis of polymer revealed that this polymer have the six‐membered ring moieties majorly. The photoluminescence peak of polymer was observed at 543 nm, which is corresponded to the photon energy of 2.51 eV. The cyclovoltamograms of the polymer exhibited the irreversible electrochemical behaviors between the doping and undoping peaks. It was found that the kinetics of the redox process of this conjugated cyclopolymer might be controlled by the diffusion‐control process from the experiment of the oxidation current density of polymer versus the scan rate.
Exploring Children's Requirements for Game-Based Learning Environments
Authors: Nousiainen Tuula , Kankaanranta Marja
Published: August 2008

End users' expertise in the development of new applications is acknowledged in user-centered and participatory design. Similarly, children's experience of what they find enjoyable and how they learn is a valuable source of inspiration for the design of products intended for them. In this paper, we explore experiences obtained from collaboration with elementary school children in the design of learning environments, based on three projects and three requirements gathering techniques. We also discuss how the children experienced the participation. The children's contribution yielded useful, both expected and unanticipated, outcomes in regard to the user interface and contents of the learning environments under development. Moreover, we present issues related to design collaboration with children, especially in terms of the children's feeling of ownership over the final outcome.
Personality Characteristics Determine Health-Related Quality of Life as an Outcome Indicator of Geriatric Inpatient Rehabilitation
Authors: Richter Jörg , Schwarz Martina , Bauer Barbara
Published: August 2008

Background. The aim of the present study was to investigate the relationships between personality and quality of life during the course of geriatric rehabilitation, against the background of Cloninger's biosocial theory of personality.Methods. All consecutive patients of a geriatric rehabilitation clinic during one year were evaluated at admission and discharge () by means of the ‘‘Vienna List’’ (a newly developed questionnaire for the assessment of quality of life in patients with severe dementia), and two variants of the Temperament and Character Inventory.Results. Self-directedness showed the most general and highest impact on quality of life and successful rehabilitation.Conclusions. It is probable in old and very old individuals who are on their highest level of maturity that the character represents the most important regulatory system in the encounter with challenges of daily life, which necessitates rehabilitation.
Region-Based Watermarking of Biometric Images: Case Study in Fingerprint Images
Authors: Zebbiche K. , Khelifi F.
Published: August 2008

In this paper, a novel scheme to watermark biometric images is proposed. It exploits the fact that biometric images, normally, have oneregion of interest, which represents the relevant part of information processable by most of the biometric-based identification/authentication systems. This proposed scheme consists of embedding the watermark into the region of interest only; thus, preserving the hidden data from the segmentation process that removes the useless background and keeps the region of interest unaltered; a process which can be used by an attacker as a cropping attack. Also, it provides more robustness and better imperceptibility of the embedded watermark. The proposed scheme is introduced into the optimum watermark detection in order to improve its performance. It is applied to fingerprint images, one of the most widely used and studied biometric data. The watermarking is assessed in two well-known transform domains: the discrete wavelet transform (DWT) and the discrete Fourier transform (DFT). The results obtained are very attractive and clearly show significant improvements when compared to the standard technique, which operates on the whole image. The results also reveal that the segmentation (cropping) attack does not affect the performance of the proposed technique, which also shows more robustness against other common attacks.
High-Temperature SOI/SiC-Based DC-DC Converter Suite
Authors: Reese Bradley A. , McPherson Brice , Shaw Robert , Hornberger Jared , Schupbach Roberto M. , Lostetter Alexander B.
Published: August 2008

A complete design strategy (mechanical and electrical) for a 25 W 28 V/5 V dc-dc converter utilizing SiC and SOI electronics is presented. The converter includes a high-temperature SOI-based PWM controller featuring 150 kHz operation, a PID feedback loop, maximum duty cycle limit, complementary or symmetrical outputs, and a bootstrapped high-side gate driver. Several passive technologies were investigated for both control and power sections. Capacitor technologies were characterized over temperature and over time at 300C∘, power inductors designed and tested up to 350C∘, and power transformers designed and tested up to 500C∘. Northrop Grumman normally-off SiC JFETs were used as power switches
and were characterized up to 250C∘. Efficiency and mass optimization routines were developed with the data gained from the first prototype. The effects of radiation on SiC and SOI electronics are then discussed. The results of the first prototype module are presented, with operation from 25C∘ up to an ambient temperature of 240C∘.
On the Plane Geometry with Generalized Absolute Value Metric
Authors: Bayar A. , Ekmekçi S. , Akça Z.
Published: August 2008

Metric spaces are among the most important widely studied topics
in mathematics. In recent years, Mathematicians began to investigate using other metrics
different from Euclidean metric. These metrics also find their place computer age in addition to their importance in geometry. In this paper, we consider the plane geometry with the generalized absolute value metric and define trigonometric functions and norm and then give a plane tiling example for engineers underlying Schwarz′s inequality in this plane.
Analysis of TROI-13 Steam Explosion Experiment
Authors: Uršič Mitja , Leskovar Matjaž
Published: August 2008

The prediction of steam explosion inducing loads in nuclear power plants must be based on results of experimental research programmes and on simulations using validated fuel-coolant interaction codes. In this work, the TROI-13 steam explosion experiment was analysed with the fuel-coolant interaction MC3D computer code. The TROI-13 experiment is one of several experiments performed in the TROI research program and resulted in a spontaneous steam explosion using corium melt. First, the TROI-13 premixing simulations were performed to determine the initial conditions for the steam explosion simulations and to evaluate the melt droplets hydrodynamic fragmentation model. Next, a number of steam explosion simulations were performed, varying the steam explosion triggering position and the melt droplets mass participating in the steam explosion. The simulation results revealed that there is an important influence of the participating melt droplets mass on the calculated pressure loads, whereas the influence of the steam explosion triggering position on the steam explosion development was less expressive.