bluuebunny/crossref_metadata_2025 huggingface dataset:
High‐Pressure Sintering of Nanocrystalline γAl2O3
Authors: Mishra Rajiv S. , Lesher Charles E. , Mukherjee Amiya K.
Published: September 2005

High‐pressure sintering of nanocrystalline γ‐A12O3 has been studied over a temperature range of 923‐1323 K and at a pressure of 1 GPa. The γ‐Al2O3 to α‐Al2O3 transformation temperature changed from 1473 K without pressure to ∼1023 K at 1 GPa. Full density was obtained at 1273 and 1323 K in 10 min. The microhardness value of fully dense α‐alumina with a grain size of 142 nm was found to be 25.3 ± 0.8 GPa. The Hall‐Petch slope for the very fine grain size range is different from that of the coarse‐grained alumina.
Silicon Nitride Oxidation Based on Oxynitride Interlayers with Graded Stoichiometry
Authors: Sheldon Brian W.
Published: September 2005

The oxidation kinetics of Si3N4 were modeled by describing the simultaneous diffusion and reaction of interstitial oxygen that is believed to occur inside of the silicon oxynitride interlayer. The oxynitride was assumed to have a variable composition, and oxidation was described as a reaction where interstitial oxygen is incorporated into the network structure of the oxynitride and nitrogen is removed. It was assumed that both the diffusion coefficient and the solubility of interstitial oxygen decrease as the nitrogen content of the network structure increases. The results accurately describe both the formation of an oxynitride layer during oxidation, and the relatively slow oxidation kinetics of Si3N4 (compared to Si and SiC).
Molecular aspects of cyst nematodes
Authors: LILLEY CATHERINE J. , ATKINSON HOWARD J. , URWIN PETER E.
Published: September 2005

Taxonomy:  Superkingdom Eukaryota; kingdom Metazoa; phylum Nematoda; class Chromadorea; order Tylenchida; suborder Tylenchina; superfamily Tylenchoidea; family Heteroderidae; subfamily Heteroderinae; main genera Heterodera and Globodera.

Host range:  Cyst nematodes comprise approximately 100 known species in six genera. They are pathogens of temperate, subtropical and tropical plant species and the host range of many species is narrow. The most economically important species are within the Globodera and Heterodera genera. Globodera pallida and G. rostochiensis are important pathogens of potato crops. There are many economic species in the Heterodera genus, including Heterodera glycines (soybean cyst nematode), H. avenae (cereal cyst nematode) and H. schachtii (sugar beet cyst nematode), the last of which attacks a range of Chenopodiaceae and Cruciferae, including Arabidopsis thaliana.

Disease symptoms:  Field symptoms of severe cyst nematode infection are often stunting, wilting and chlorosis, but considerable yield loss can occur without obvious symptoms. The only unique indicator of cyst nematode infection is the presence of adult female nematodes attached to host roots after several weeks of parasitism.

Disease control:  This is usually achieved by using integrated pest management involving cultural practices such as crop rotation, resistant cultivars if available and chemical control when economically justified.
Lack of predictors of normalization of oesophageal acid exposure in Barrett's oesophagus
Authors: WANI S. , SAMPLINER R. E. , WESTON A. P. , MATHUR S. , HALL M. , HIGBEE A. , SHARMA P.
Published: September 2005

Background : Barrett's oesophagus patients may continue to have abnormal oesophageal acid exposure on proton pump inhibitor therapy. The effect of factors such as Barrett's oesophagus length, hiatal hernia size and Helicobacter pylori infection on intra‐oesophageal pH in Barrett's oesophagus patients has not been adequately studied.

Aim : To evaluate oesophageal acid exposure in a large Barrett's oesophagus population on b.d. proton pump inhibitor therapy and determine clinical factors predicting normalization of intra‐oesophageal pH on therapy.

Methods : Barrett's oesophagus patients were studied using 24 h pH monitoring to evaluate intra‐oesophageal acid suppression on b.d. dosing of rabeprazole.

Results : Forty‐six Barrett's oesophagus patients completed the study. Median total percentage time pH < 4 was 1.05% (range: 0–29.9%) in the entire group and respective values for upright and supine percentage time pH < 4 were 1.15% and 0%. However, 34 of the Barrett's oesophagus patients (73.9%) had a normal pH study (median total percentage time pH < 4: 0.2%) and 12 patients (26.1%) had an abnormal result (median total percentage time pH < 4: 9.3%). There were no significant differences between patients with a normal and abnormal 24 h pH result with respect to age, Barrett's oesophagus length, hiatal hernia size and presence of H. pylori infection.

Conclusions : Approximately 25% of Barrett's oesophagus patients continue to have abnormal total intra‐oesophageal pH profiles despite b.d. proton pump inhibitor therapy. Factors such as age, Barrett's oesophagus length and hiatal hernia size cannot be used to predict persistent abnormal intra‐oesophageal pH on proton pump inhibitor.
Review article: anorexia and cachexia in gastrointestinal cancer
Authors: OCKENGA J. , VALENTINI L.
Published: September 2005

In patients with gastrointestinal malignancies, i.e. cancers of the stomach, colon, liver, biliary tract or pancreas, progressive undernutrition can be regularly observed during the course of illness. Undernutrition significantly affects the patients’ quality of life, morbidity and survival.

Pathogenetically, two different causes are relevant in the development of undernutrition in patients with gastrointestinal cancer. One cause is reduced nutritional intake. This condition is referred to as anorexia and can be worsened by the side effects of cancer therapy. The other cause is the release of endogenous transmitters and/or other products of the tumour leading to the cachexia syndrome, which is characterized by loss of body weight, negative nitrogen balance and fatigue. Cancer anorexia and cancer cachexia may have synergistic negative effects in affecting the patients’ status.

In this review, current nutritional support strategies with respect to different clinically relevant situations are described. An algorithm of the treatment strategies, including dietetic counselling, oral supplements, enteral and parenteral nutritional support is given. One focus is the approach of nutrition‐focused patient care, which shows promising results. In addition, the possibilities of pharmacological intervention are discussed.
Pharmacokinetic interaction between verapamil and everolimus in healthy subjects
Authors: Kovarik J. M. , Beyer D. , Bizot M. N. , Jiang Q. , Allison M. J. , Schmouder R. L.
Published: September 2005

Aims

We sought to define the influence of verapamil, an inhibitor of CYP3A and P‐glycoprotein, on the pharmacokinetics of everolimus, a substrate of this enzyme and transporter.

Methods

This was a two‐period, single‐sequence, crossover study in 16 healthy subjects. In period 1 subjects received a single 2 mg oral dose of everolimus. In period 2 they received verapamil 80 mg three times daily for a total of 6 days and a single 2 mg dose of everolimus co‐administered on the second day of verapamil therapy.

Results

During verapamil co‐administration, everolimus Cmax increased 2.3‐fold (90% CI, 1.9, 2.7) from 21 ± 8 to 47 ± 18 ng ml−1 and AUC increased 3.5‐fold (90% CI, 3.1, 3.9) from 115 ± 45 to 392 ± 142 ng ml−1 h. Everolimus half‐life was only prolonged to a minor extent (32 ± 6 vs. 37 ± 6 h). Verapamil predose concentrations doubled from 32 ± 16 to 74 ± 42 ng ml−1 after single dose administration of everolimus.

Conclusions

Multiple dosing with verapamil increased blood concentrations of everolimus after a single dose by an average 3.5‐fold. During verapamil treatment, dose reduction for everolimus should be made guided by blood monitoring and for verapamil by blood pressure monitoring.
Inappropriate initial treatment of secondary intra‐abdominal infections leads to increased risk of clinical failure and costs
Authors: Sturkenboom Miriam C. J. M. , Goettsch Wim G. , Picelli Gino , In‘t Veld Bas , Yin Don D. , De Jong Romy B. , Go Peter M. N. Y. H. , Herings Ron M. C.
Published: September 2005

Aims

The objective of this population‐based, retrospective cohort study was to investigate the incidence and initial antibiotic treatment of secondary intra‐abdominal infections (sIAI) and to assess whether inappropriate initial antibiotic therapy affects patient outcomes.

Methods

All patients hospitalized for sIAI (1995–1998) were identified in the PHARMO Record Linkage System, a patient‐centric database including pharmacy dispensing records from community pharmacies linked to hospitalization records in the Netherlands. Complementary in‐hospital antibiotic drug use was obtained from the computerized inpatient pharmacy files. The patient outcomes considered were switch to second‐line antibiotic treatment, re‐operation, and death. In addition, a composite variable clinical failure was constructed based on the above‐mentioned outcomes. Furthermore, the effect of clinical failure on length of hospital stay and costs of hospitalization was assessed. Associations between appropriateness of initial antibiotic treatment and outcomes were estimated using multivariate logistic and linear regression models.

Results

In the source population of 228 000 persons, 175 cases were classified as sIAI (mean age 49.3 ± 24.5, 50.9% male) resulting in an incidence of 2.3/10 000 person‐years [95% confidence interval (CI) 2.0, 2.7]. Initial antibiotic treatment was appropriate for 84% of the cases. The risk of clinical failure was 17.1%. Inappropriate initial antibiotic treatment increased the risk of clinical failure 3.4‐fold (95% CI 1.3, 9.1). Length of hospital stay and costs of hospitalization were significantly increased for patients with clinical failure.

Conclusions

Inappropriate choice of initial antibiotic therapy in sIAI patients leads to more clinical failure resulting in a longer hospital stay and higher costs of hospitalization compared with appropriate initial antibiotic therapy.
Endocrine and inflammatory markers as predictors of frailty
Authors: Puts Martine T. E. , Visser Marjolein , Twisk Jos W. R. , Deeg Dorly J. H. , Lips Paul
Published: September 2005

Objective  To examine the association of serum concentrations of 25‐hydroxyvitamin D [25(OH)D], interleukin‐6 (IL‐6), C‐reactive protein (CRP) and IGF‐1 with prevalent and incident frailty.

Design  The Longitudinal Aging Study Amsterdam (LASA), a prospective cohort study with 3‐yearly measurement cycles.

Setting  General population‐based sample.

Participants  The respondents were men and women aged 65 and over, who participated at T1 (1995/1996, N = 1720) and T2 (1998/1999, N = 1509). Blood samples were obtained at T1 (N = 1271).

Measurements  The presence of frailty at T1 and 3‐year incidence of frailty. Frailty is defined as the presence of three out of nine frailty indicators.

Results  At T1, 242 (19·0%) of all respondents were frail. Those who were frail at T1 had higher CRP and lower 25(OH)D levels. Serum 25(OH)D remained associated with frailty after adjustment for potential confounders with an odd ratios (OR) of 2·60 [95% confidence interval (95% CI) 1·60–4·21] for 25(OH)D < 25 nmol/l and 1·72 (95% CI 1·19–2·47) for 25(OH)D 25–50 nmol/l vs. high levels of 25(OH)D. Of the nonfrail at T1, 125 respondents (14·1%) became frail at T2. After adjustment, moderately elevated CRP levels (3–10 µg/ml) (OR 1·69, 95% CI 1·09–2·63) and low 25(OH)D (OR 2·04, 95% CI 1·01–4·13) were associated with incident frailty. No consistent associations were observed for IL‐6 and IGF‐1.

Conclusion  Low 25(OH)D levels were strongly associated with prevalent and incident frailty; moderately elevated levels of CRP were associated with incident frailty.
Observations from moorings in the Aleutian Passes: temperature, salinity and transport
Authors: STABENO P. J. , KACHEL D. G. , KACHEL N. B. , SULLIVAN M. E.
Published: September 2005

Between May 2001 and September 2003, a series of moorings were deployed in four of the Aleutian Passes – Tanaga Pass (12 months of data), Akutan Pass and Seguam Pass (18 months), and Amukta Pass (36 months). Instruments on each mooring measured temperature, salinity and current velocity. Tidal currents dominated the flow in each pass, including a strong fortnightly component in the three deeper passes (Tanaga, Seguam, and Amukta). Net transport in each of the passes was northward, varying from 0.1 × 106 m3 s−1 in Akutan Pass and 0.4 × 106 m3 s−1 in Seguam to >4.0 × 106 m3 s−1 in Amukta Pass. The transport in Amukta Pass, calculated from current meters, was approximately five times as large as previously estimated from hydrographic surveys. At monthly and longer periods, the variability in transport in Amukta Pass was related to the position and strength of the Alaskan Stream southeast of the pass. Vertical mixing was examined in Akutan and Seguam Passes. Strong tidal currents mix the water column top‐to‐bottom over the shallow sills in the passes, a depth of 80 m in Akutan and 140 m in Seguam Pass, providing a critical source of nutrients to the Bering Sea ecosystem.
Spatial and temporal variability of the Aleutian climate
Authors: RODIONOV SERGEI N. , OVERLAND JAMES E. , BOND NICHOLAS A.
Published: September 2005

The objective of this paper is to highlight those characteristics of climate variability that may pertain to the climate hypothesis regarding the long‐term population decline of Steller sea lions (Eumetopias jubatus). The seasonal changes in surface air temperature (SAT) across the Aleutian Islands are relatively uniform, from 5 to 10°C in summer to near freezing temperatures in winter. The interannual and interdecadal variations in SAT, however, are substantially different for the eastern and western Aleutians, with the transition found at about 170°W. The eastern Aleutians experienced a regime shift toward a warmer climate in 1977, simultaneously with the basin‐wide shift in the Pacific Decadal Oscillation (PDO). In contrast, the western Aleutians show a steady decline in winter SATs that started in the 1950s. This cooling trend was accompanied by a trend toward more variable SAT, both on the inter‐ and intra‐annual time scale. During 1986–2002, the variance of winter SATs more than doubled compared to 1965–1985. At the same time in Southeast Alaska, the SAT variance diminished by half. Much of the increase in the intra‐seasonal variability for the western Aleutians is associated with a warming trend in November and a cooling trend in January. As a result, the rate of seasonal cooling from November to January has doubled since the late 1950s. We hypothesize that this trend in SAT variability may have increased the environmental stress on the western stock of Steller sea lions and hence contributed to its decline.
Nutrients and primary production along the eastern Aleutian Island Archipelago
Authors: MORDY CALVIN W. , STABENO PHYLLIS J. , LADD CAROL , ZEEMAN STEPHAN , WISEGARVER DAVID P. , SALO SIGRID A. , HUNT GEORGE L.
Published: September 2005

The distribution of nutrients (nitrate, phosphate, and silicic acid), chlorophyll and primary productivity were examined in the central and eastern Aleutian Archipelago. The data were collected from moorings (temperature, salinity, nitrate, and currents) and two hydrographic research cruises (June 2001 and May–June 2002). During the hydrographic cruises salinity, temperature, nutrients, chlorophyll and primary production were measured in and around the eastern and central Aleutian Passes. The net nutrient transport through the passes was northward, and it was relatively low in the eastern passes compared to the central passes. In the shallow eastern passes the source water from the Pacific was the nutrient‐poor Alaska Coastal Current, while in the deeper central passes it was the nutrient‐rich Alaskan Stream. Within the passes, vigorous tidal mixing resulted in enriched surface concentrations, especially in the central passes. Chlorophyll sections and satellite composites from summer indicate high chlorophyll east of Samalga Pass and very low chlorophyll between Samalga and Seguam Passes. Production was relatively low across the study area, except at the northern end of Seguam Pass and in the vicinity of the shelf edge in the southeastern Bering Sea. Production and chlorophyll concentrations were lowest in the deep passes. These results suggest that, within the passes, deep mixing inhibits new production, but substantial blooms may occur downstream of the passes subsequent to stratification.
Distribution patterns and population trends of breeding seabirds in the Aleutian Islands
Authors: VERNON BYRD G. , RENNER HEATHER M. , RENNER MARTIN
Published: September 2005

The 1800‐km‐long Aleutian Archipelago is a breeding area for more than 10 million seabirds of 26 species. We evaluated the distribution of breeding colonies of 24 common breeding species in relationship to ocean passes of two sizes, availability of nesting habitat and the distribution of introduced predatory mammals. Further, we evaluated population trends and reproductive rates to amplify information about distribution. We compared distributions and demographic parameters based on proposed differences in marine habitats in the eastern, central and western Aleutians. Samalga Pass did not appear to be a break point for breeding seabird distribution as is suggested for oceanographic characteristics and other species groups by papers in this volume. Factors affecting distribution varied with foraging and nesting strategies of various species groups. The three largest breeding aggregations of seabirds in the Aleutians (Buldir, Chagulak and Kiska) all have relatively high species diversity and are located next to large passes. However, when other predictors were considered, proximity to medium or large passes was important mainly for surface‐feeding piscivores. The extent of nesting habitat apparently does not limit the distribution of surface‐ or burrow‐nesting species (including planktivores and piscivores). Instead, the distribution of these species probably has been shaped by introduced mammals. Nesting habitat for ledge‐ and crevice‐nesting species is more limited than for surface and burrow nesters but is still fairly widespread. Ledge‐ and crevice‐nesting species are less susceptible to fox predation than are surface and burrow nesters. These species may have been reduced by predation but were not extirpated.
An ecological classification of Alaskan Steller sea lion (Eumetopias jubatus) rookeries: a tool for conservation/management
Authors: CALL KATHERINE A. , LOUGHLIN THOMAS R.
Published: September 2005

As the western stock of Steller sea lions continues to decline, government managers may place additional controls on commercial fisheries as protective measures. Currently, management decisions regarding rookeries are based largely on the geographic location of a site, and little effort has been made to describe sea lion rookeries in an ecosystem context. We provide a broad ecological characterization of rookeries for the western stock of Steller sea lions, which can be used in making management decisions to facilitate their recovery. We gathered data on habitat (bathymetry, sea surface temperature, substrate type, and orientation), diet and population trends from available literature and National Marine Fisheries Service databases (1990–98), and we used a Geographic Information System to group sea lion rookeries into ecologically related regions. Ecological attributes were assigned to rookeries within a 10‐nm radius of land. Regions were determined using cluster analysis. Five distinct classes of rookeries (i.e. potential management regions) were identified based on their relatedness to the ecological factors we defined. Several of the regional breaks occur at major oceanic passes including Amchitka, Samalga, and Unimak Passes and are associated with ocean currents.
Seabird distribution, abundance and diets in the eastern and central Aleutian Islands
Authors: JAHNCKE J. , COYLE K. O. , HUNT GEORGE L.
Published: September 2005

We examined the hypothesis that seabird distribution, abundance and diets differ among the eastern and central Aleutian Islands in response to distinct marine environments and energy pathways in each region. Research cruises were conducted in June 2001 and May–June 2002. We determined the distribution, abundance, diet and prey consumption of seabirds, and related these to zooplankton abundance and water masses that possess different physical properties. We found that distribution, abundance and diets of seabirds could be partitioned into two regions that correspond to marine environments determined by the extent of the Alaska Coastal Current along the eastern and central Aleutian Islands. Short‐tailed shearwaters (Puffinus tenuirostris) were the most abundant seabird in the coastal waters of the eastern Aleutian Islands, and northern fulmars (Fulmarus glacialis) were the most abundant seabird in the oceanic waters of the central Aleutian Islands. Seabird communities in the central and eastern Aleutian Islands were likely associated with different food webs. In the central Aleutian Islands, short‐tailed shearwaters and northern fulmars consumed shelf‐break species of euphausiids (Thyssanoesa longipes) and oceanic copepods (Neocalanus cristatus), respectively; in the eastern Aleutian Islands, both short‐tailed shearwaters and northern fulmars consumed shelf species of euphausiids (T. inermis). Carbon transport to seabirds was highest in Unimak and Akutan Passes where shearwaters removed large quantities of shelf euphausiids, followed by Samalga and Seguam Passes where northern fulmars removed large amounts of oceanic copepods.
Do patterns of Steller sea lion (Eumetopias jubatus) diet, population trend and cetacean occurrence reflect oceanographic domains from the Alaska Peninsula to the central Aleutian Islands?
Authors: SINCLAIR ELIZABETH H. , MOORE SUE E. , FRIDAY NANCY A. , ZEPPELIN TONYA K. , WAITE JANICE M.
Published: September 2005

Shipboard surveys were conducted along the Aleutian Islands in 2001 and 2002 to assess the influence of a suite of biophysical parameters on regional patterns in the distribution of cetaceans and Steller sea lions (SSL; Eumetopias jubatus). Distributions of four large whale species: fin (Balaenoptera physalus), humpback (Megaptera novaeangliae), minke (B. acutorostrata) and sperm (Physeter macrocephalus) aligned with proposed metapopulation breaks in diet and population trend of SSLs. Dall's porpoise (Phocoenoides dalli) and killer whales (Orcinus orca) were widely distributed throughout the study area, and killer whales were particularly prevalent along the north Aleutian Island coastlines between Unimak Pass and Samalga Pass. Biopsies determined that most killer whales (92%) were of the piscivorous (resident) ecotype as opposed to the mammal‐eating (transient) ecotype observed in 2002 only. Generalized additive models (GAMs) were used to explore relationships between these multispecies patterns in distribution, oceanographic variables (salinity, temperature, fluorescence and depth) and proximity to six Aleutian passes. The GAMs indicated the best‐fit models and most significant correlations as determined by the Akaike function and Cp‐statistics were: depth and proximity to the nearest measured pass for SSLs and all cetaceans, respectively; frequencies of herring and salmon in SSL diet with population trend; fluorescence in the top 50 m with occurrence of humpback, minke, and killer whales; and surface temperature with occurrence of humpback, killer, and sperm whales. Results of the GAM analyses suggest foci for future investigation of relationships between physical variables and interspecific patterns of marine mammal distribution.
Toward sustainable ecosystem services from the Aleutian Archipelago
Authors: SCHUMACHER J. D. , KRUSE GORDON H.
Published: September 2005

The new research reported in this special issue of Fisheries Oceanography expands our understanding of the Aleutian Archipelago ecosystem. Yet our knowledge remains very limited, while the use of this ecosystem for commercial activities, recreation and other purposes expands. Given this situation, how can we sustain the ecosystem services (food, fuel, fibers as well as spiritual, recreational, educational and other non‐material benefits to society) of this region? The region has a mixed history; healthy populations of many species exist, but so do species extinctions (e.g. Steller sea cow, Hydrodamalis gigas) and population depletions, including the sea otter (Enhydra lutris), Steller sea lion (Eumetopias jubatus), whiskered auklets (Aethia pygmaea), Pacific ocean perch (Sebastes alutus), and red king crabs (Paralithodes camtschaticus), associated with human impacts. The solution to our limited knowledge in this poorly studied region is increased funding for ecosystem research, including its responses to climate change and human impacts. Knowledge is not sufficient, however; a change in management approach is also needed. We emphasize the need to maintain a broader set of ecosystem services objectives rather than the traditional narrower focus on commercial fishery yields. To do so, we recommend the development of an integrated ecosystem services management plan for the Aleutian Islands. Such a plan requires that state and federal regulatory agencies coordinate with a broad stakeholder community involving sectors of commercial and recreational fishing, subsistence, conservation, oil and gas development, coastal development, shipping, tourism, and others.
Net heterotrophy in Faroe Islands clear‐water lakes: causes and consequences for bacterioplankton and phytoplankton
Authors: PÅLSSON CARINA , KRITZBERG EMMA S. , CHRISTOFFERSEN KIRSTEN , GRANÉLI WILHELM
Published: September 2005

1. Five oligotrophic clear‐water lakes on the Faroe Islands were studied during August 2000. Algal and bacterial production rates, community respiration, and CO2 saturation were determined. In addition, we examined the plankton community composition (phytoplankton and heterotrophic nanoflagellates) and measured the grazing pressure exerted by common mixotrophic species on bacteria.

2. High respiration to primary production (6.6–33.2) and supersaturation of CO2 (830–2140 μatm) implied that the lakes were net heterotrophic and that the pelagic heterotrophic plankton were subsidised by allochthonous organic carbon. However, in spite of the apparent high level of net heterotrophy, primary production exceeded bacterial production and the food base for higher trophic levels appeared to be mainly autotrophic.

3. We suggest that the observed net heterotrophy in these lakes was a result of the oligotrophic conditions and hence low primary production in combination with an input of allochthonous C with a relatively high availability.

4. Mixotrophic phytoplankton (Cryptomonas spp., Dinobryon spp. and flagellates cf. Ochromonas spp.) constituted a large percentage of the plankton community (17–83%), possibly as a result of their capacity to exploit bacteria as a means of acquiring nutrients in these nutrient poor systems.
Continuous monitoring of phytoplankton dynamics in Lake Balaton (Hungary) using on‐line delayed fluorescence excitation spectroscopy
Authors: ISTVÁNOVICS VERA , HONTI MÁRK , OSZTOICS ANDRÁS , SHAFIK HESHAM M. , PADISÁK JUDIT , YACOBI YOSSEF , ECKERT WERNER
Published: September 2005

1. This study introduces delayed fluorescence (DF) excitation spectroscopy as an on‐line tool for in situ monitoring of the composition and biomass of various colour classes of phytoplankton when they are photosynthetically active (cyanobacteria, chlorophytes, chromophytes and cryptophytes). The DF data are validated by comparison with those from conventional methods (weekly microscopic counts and the measurement of chlorophyll concentration).

2. The composition of phytoplankton as assessed by DF agreed reasonably well with the results from microscopic counts, particularly when differences in chlorophyll‐specific DF integrals of the various colour classes were taken into account.

3. Integrals of DF spectra were converted into concentration of chlorophyll a using empirical factors derived from field data. The value of the conversion factor was nearly twice as high when the relative abundance of cyanobacteria was low (<15%) than when it was high. The converted DF‐chl time series agreed well with chlorophyll measurements particularly when blooms were developing. As the DF method is inherently free of the interference caused by pigment degradation products, the discrepancy between the two data sets increased during the collapse of blooms and when sediment resuspension was intense.

4. Fourier spectrum analysis of the time series of DF‐chl indicated that samples must be taken, at a minimum, every 2–3 days to capture the dynamics of phytoplankton. As a consequence, the dynamics of various algal blooms, including their timing, duration and net growth rate, could be estimated with greater confidence than by using conventional methods alone.

5. On‐line DF spectroscopy is an advanced technique for monitoring daily the biomass and composition of the photosynthetically active phytoplankton in aquatic environments, including turbid shallow lakes. At present, the detection limit is around 1 mg DF‐chl a m−3 in terms of total biomass but confidence in estimates of phytoplankton composition declines sharply below about 5 mg chl a m−3.

6. On‐line DF spectroscopy represents a promising approach for monitoring phytoplankton. It will be useful in water management where it can act as an early‐warning system of declines in water quality. In basic ecological research it can supplement manual methods. While default calibration spectra may be acceptable for routine monitoring, we suggest a careful individual calibration of the DF spectrometer for basic research. The statistical methods developed here help to assess the adequacy of various calibration sets.
Hardening capacity in the Drosophila melanogaster species group is constrained by basal thermotolerance
Authors: KELLETT M. , HOFFMANN A. A. , MCKECHNIE S. W.
Published: September 2005

To determine the relationship between basal thermotolerance and hardening capacity across related taxa, these traits were quantified for eight Drosophila species: D. melanogaster, D. simulans, D. sechellia and D. yakuba of the melanogaster subgroup and D. auraria, D. vulcana, D. serrata and D. birchii of the montium subgroup. The effects of pretreatment temperature and recovery time between pretreatment and heat shock on thermotolerance were also assessed.

For any given species, all elevated temperature pretreatments (31 °C, 33 °C and 35 °C) equally increased thermotolerance.

For any given species, increasing recovery time between pretreatment and heat shock increased thermotolerance, though this effect may be related to factors other than hardening.

Basal thermotolerance and absolute hardening capacity (pretreated thermotolerance minus basal thermotolerance) varied considerably among the species, and was not phylogenetically clustered.

Though unmodified and phylogenetically corrected correlations indicated a relationship between basal thermotolerance and absolute hardening capacity, this result was largely due to the presence of one species, the highly thermotolerant D. melanogaster.

Relative hardening capacity (absolute hardening capacity divided by basal thermotolerance) was fixed for all species at approximately 0·25.
Do faster starts increase the probability of evading predators?
Authors: WALKER J. A. , GHALAMBOR C. K. , GRISET O. L. , McKENNEY D. , REZNICK D. N.
Published: September 2005

Nearly all fish evade predation strikes by rapidly accelerating out of the strike path, a behaviour called the fast‐start evasion response. The many studies investigating morphological, behavioural and ecological correlates of fast‐start performance assume that faster starts increase the probability of evasion.

We tested this faster‐start hypothesis by measuring the effect of acceleration ability on evasion outcome (success, failure) in Guppies (Poecilia reticulata) evading the strike of a natural predator, the Pike Cichlid (Crenicichla alta).

Four parameters affect evasion outcome: two parameters important to the predator–prey interaction but not to the faster‐start hypothesis – (1) the time required to reach the prey by the striking predator (measured by the initial distance between predator and prey and strike velocity), (2) the evasion path of the prey relative to the strike path of the predator; and two parameters relevant to the faster‐start hypothesis – (1) the ability of the prey to generate rapid tangential acceleration (measured by net distance travelled, maximum velocity, and maximum acceleration), and (2) the ability of the prey to rapidly rotate during the initial stage of the fast start.

On average, a one standard deviation increase in fast‐start performance increases the odds of surviving a predation strike 2·3‐fold. These results support the assumption that faster starts increase the probability of successfully evading a predation strike.
Traits of recalcitrant seeds in a semi‐deciduous tropical forest in Panamá: some ecological implications
Authors: DAWS M. I. , GARWOOD N. C. , PRITCHARD H. W.
Published: September 2005

We used cross‐species and phylogenetic analyses to compare seed traits of 36 species with desiccation‐sensitive and 189 with desiccation‐tolerant seeds from a semi‐deciduous forest in Panamá.

When correcting for phylogenetic dependence between taxa, the desiccation‐sensitive seeds were significantly larger than desiccation‐tolerant seeds (3383 vs 283 mg) and typically shed during the wet (as opposed to dry) season. Both traits presumably reduce the rate of seed drying and hence the risk of desiccation‐induced mortality for the desiccation‐sensitive species.

Growing‐house germination trials in simulated understorey and canopy gap environments revealed that the desiccation‐sensitive species germinated most rapidly. Additionally, on a proportion basis, the desiccation‐sensitive seeds allocated significantly less resources to seed physical defences (endocarp and/or testa) which may partially facilitate rapid germination. Both relationships were significant when correcting for phylogenetic dependence and seed mass.

Our results suggest that, for large‐seeded species which will dry slowly, desiccation sensitivity may be advantageous. Rapid germination may reduce the duration of seed exposure to predation, and the low investment in physical defence means that, per unit mass, desiccation‐sensitive seeds are a more efficient use of resources in seed provisioning.
Carotenoid ornamentation of adult male Common Redpolls predicts probability of dying in a salmonellosis outbreak
Authors: VAN OORT H. , DAWSON R. D.
Published: September 2005

Conditional handicap models of sexual selection predict that ornamentation should be positively associated with an individual's ability to withstand challenges to their health.

We assessed whether levels of carotenoid ornamentation were related to the probability of adult male Common Redpolls, Carduelis flammea, dying in a salmonellosis epidemic by comparing the ornamentation of surviving adult male redpolls to those found dead. Hosts suffering from salmonellosis shed bacteria in faeces, and new individuals are typically infected when they ingest faeces‐contaminated food.

The proportion of adult males in the sample of dead birds was significantly higher than in the sample of living birds.

Among adult males, probability of survival was significantly predicted by the expression of their carotenoid signals: brightly ornamented adult males were more likely to die in the epidemic.

A probable hypothesis for these results is that if carotenoid ornamentation in redpolls functions as a status badge of dominance, bright males would have had priority access to highly preferred, and contaminated, food patches.
Morphology, performance and fighting capacity in male lizards, Gallotia galloti
Authors: HUYGHE K. , VANHOOYDONCK B. , SCHEERS H. , MOLINA‐BORJA M. , VAN DAMME R.
Published: September 2005

Morphological characteristics (snout–vent length, badge area, mass, limb and head measures) and whole‐animal performance capacities (sprint speed, acceleration capacity, stamina and bite force) were measured in male lizards, Gallotia galloti. These males were also tested in paired staged contests to assess relative fighting capacity and to link these results to morphology and performance.

A multivariate analysis of the four performance features revealed a clear difference between the physiological capacities of winners vs losers, with bite force being the most important predictor of the outcome of fights.

The finding that bite performance is linked to dominance fits in with the high sexual dimorphism in head size in this species, as head size is a predictor of bite force performance.

Winners of contests also tended to have larger total areas of blue patches on their sides, suggesting that these badges convey information on the social status of the males. However, since no correlation was found between bite force and badge size, the patches seem to contain information on a component of fighting capacity other than bite force.
Nitric oxide (NO) as an intermediate in the cryptogein‐induced hypersensitive response – a critical re‐evaluation
Authors: PLANCHET ELISABETH , SONODA MASATOSHI , ZEIER JÜRGEN , KAISER WERNER M.
Published: September 2005

A hypersensitive response (HR) was induced in tobacco leaves and cell suspensions by the fungal elicitor cryptogein, and NO production was followed by chemiluminescence and occasionally by diaminofluorescein (DAF)‐fluorescence. Results from both methods were at least partly consistent, but kinetics was different. NO emission was not induced by cryptogein in leaves, whereas in cell suspensions some weak NO emission was observed, which was nitrate reductase (NR)‐dependent, but not required for cell death. Nitric oxide synthase (NOS) inhibitors did not prevent cell death, but PR‐1 expression was weakened. In conclusion, neither NR nor NOS appear obligatory for the cryptogein‐induced HR. However, a role for NO was still suggested by the fact that the NO scavenger cPTIO prevented the HR. Unexpectedly, cPTI, the reaction product of cPTIO and NO, also impaired the HR but without scavenging NO. Thus, prevention of the HR by cPTIO is not necessarily indicative for a role of NO. Further, even a 100‐fold NO overproduction (over wild type) by a nitrite reductase‐deficient mutant did not interfere with the cryptogein‐induced HR. Accordingly, the role of NO in the HR should be reconsidered.
Evidence from Amazonian forests is consistent with isohydric control of leaf water potential
Authors: FISHER ROSIE A. , WILLIAMS MATHEW , DO VALE RAQUEL LOBO , DA COSTA ANTONIO LOLA , MEIR PATRICK
Published: September 2005

Climate modelling studies predict that the rain forests of the Eastern Amazon basin are likely to experience reductions in rainfall of up to 50% over the next 50–100 years. Efforts to predict the effects of changing climate, especially drought stress, on forest gas exchange are currently limited by uncertainty about the mechanism that controls stomatal closure in response to low soil moisture. At a through‐fall exclusion experiment in Eastern Amazonia where water was experimentally excluded from the soil, we tested the hypothesis that plants are isohydric, that is, when water is scarce, the stomata act to prevent leaf water potential from dropping below a critical threshold level. We made diurnal measurements of leaf water potential (Ψl), stomatal conductance (gs), sap flow and stem water potential (Ψstem) in the wet and dry seasons. We compared the data with the predictions of the soil–plant–atmosphere (SPA) model, which embeds the isohydric hypothesis within its stomatal conductance algorithm. The model inputs for meteorology, leaf area index (LAI), soil water potential and soil‐to‐leaf hydraulic resistance (R) were altered between seasons in accordance with measured values. No optimization parameters were used to adjust the model. This ‘mechanistic’ model of stomatal function was able to explain the individual tree‐level seasonal changes in water relations (r2 = 0.85, 0.90 and 0.58 for Ψl, sap flow and gs, respectively). The model indicated that the measured increase in R was the dominant cause of restricted water use during the dry season, resulting in a modelled restriction of sap flow four times greater than that caused by reduced soil water potential. Higher resistance during the dry season resulted from an increase in below‐ground resistance (including root and soil‐to‐root resistance) to water flow.
Activation of Natural Killer‐Like YT‐INDY Cells by Oligodeoxynucleotides and Binding by Homologous Pattern Recognition Proteins
Authors: Kaur H. , Jaso‐Friedmann L. , Leary J. H. , Praveen K. , Brahmi Z. , Evans D. L.
Published: September 2005

The present study was designed to examine the binding and signalling effects of single base and CpG dinucleotide phosphodiester (Po) oligodeoxynucleotides (ODN) on the human natural killer (NK)‐like cell line (YT‐INDY). Single base Po ODN composed of 20‐mers of guanosine (dG20), adenosine (dA20), cytosine (dC20) or thymidine (dT20) as well as ‘conventional’ Po CpG ODN were examined for their ability to bind and activate YT‐INDY cells. Binding by dG20 and CpG ODN to YT‐INDY cells was saturable and specific. dG20 binding was competitively inhibited by homologous dG20 and heterologous CpG ODN but not by dC20 and dA20. Two different YT‐INDY membrane proteins (18 and 29 kDa) were identified by ligand (Southwestern) blotting with biotinylated dG20 and CpG. The specificity of the ODN‐binding protein(s) was further confirmed by ODN depletion experiments using a teleost recombinant protein orthologue [nonspecific cytotoxic cells (NCC) cationic antimicrobial protein‐1 (ncamp‐1)] known to bind CpG and dG20. Cell proliferation and activation studies showed that dG20 and CpG treatment of YT‐INDY cells induced cellular DNA synthesis (i.e. G1 to S‐phase conversion). This signalling function was accompanied in dG20‐treated cells by proliferation 10 h posttreatment. Both dG20 and CpG ODN binding induced a calcium flux in YT‐INDY cells within seconds of treatment. These experiments demonstrated that Po single base dG20 and CpG ODN bind to a (potential) new class of cell‐surface proteins that mediate the activation of YT‐INDY cells.
Burial‐exhumation history of the central Apennines (Italy), from the foreland to the chain building: thermochronological and geological data
Authors: Rusciadelli G. , Viandante M.G. , Calamita F. , Cook A.C.
Published: September 2005

A clear correlation between regional unconformities and related exhumation events was documented by thermochronological and geological data in the central Apennines. This approach allowed: (i) two major exhumation episodes to be identified, corresponding to turning points in the long‐term burial history, from rifting to convergent margin development, and (ii) a quantification of the amount of section removed during the two exhumation events. The first exhumation event was connected with the foreland buckling process associated with the coupling between the Alpine–Apennines system, the Dinarides chain and their common foreland. During the Neogene a thrust‐system development, the superposition of an allochthonous unit is envisaged to explain the second palaeoheating event. The dismantling of this additional load in central Apennines has been related to the formation of the Middle Pliocene Unconformity, during the development of the Pliocene–Quaternary frontal thrust of the Apennine Chain.
The Rpi‐blb2 gene from Solanum bulbocastanum is an Mi‐1 gene homolog conferring broad‐spectrum late blight resistance in potato
Authors: van der Vossen Edwin A.G. , Gros Jack , Sikkema Anne , Muskens Marielle , Wouters Doret , Wolters Petra , Pereira Andy , Allefs Sjefke
Published: September 2005

The necessity to develop potato and tomato crops that possess durable resistance against the oomycete pathogen Phytophthora infestans is increasing as more virulent, crop‐specialized and pesticide resistant strains of the pathogen are rapidly emerging. Here, we describe the positional cloning of the Solanum bulbocastanum‐derived Rpi‐blb2 gene, which even when present in a potato background confers broad‐spectrum late blight resistance. The Rpi‐blb2 locus was initially mapped in several tetraploid backcross populations, derived from highly resistant complex interspecific hybrids designated ABPT (an acronym of the four Solanum species involved:S. acaule, S. bulbocastanum, S. phureja and S. tuberosum), to the same region on chromosome 6 as the Mi‐1 gene from tomato, which confers resistance to nematodes, aphids and white flies. Due to suppression of recombination in the tetraploid material, fine mapping was carried out in a diploid intraspecific S. bulbocastanum F1 population. Bacterial artificial chromosome (BAC) libraries, generated from a diploid ABPT‐derived clone and from the resistant S. bulbocastanum parent clone, were screened with markers linked to resistance in order to generate a physical map of the Rpi‐blb2 locus. Molecular analyses of both ABPT‐ and S. bulbocastanum–derived BAC clones spanning the Rpi‐blb2 locus showed it to harbor at least 15 Mi‐1 gene homologs (MiGHs). Of these, five were genetically determined to be candidates for Rpi‐blb2. Complementation analyses showed that one ABPT‐ and one S. bulbocastanum‐derived MiGH were able to complement the susceptible phenotype in both S. tuberosum and tomato. Sequence analyses of both genes showed them to be identical. The Rpi‐blb2 protein shares 82% sequence identity to the Mi‐1 protein. Significant expansion of the Rpi‐blb2 locus compared to the Mi‐1 locus indicates that intrachromosomal recombination or unequal crossing over has played an important role in the evolution of the Rpi‐blb2 locus. The contrasting evolutionary dynamics of the Rpi‐blb2/Mi‐1 loci in the two related genomes may reflect the opposite evolutionary potentials of the interacting pathogens.
Optimization of biometry for intraocular lens implantation using the Zeiss IOLMaster
Authors: Madge Simon N. , Khong C. H. , Lamont Meon , Bansal Atul , Antcliff Richard J.
Published: September 2005

Purpose:  To compare the accuracy of biometry using conventional A‐scan ultrasonography and partial coherence interferometry, and to improve the accuracy of biometry by sequential audit of postoperative refractive error.

Methods:  The study was performed in three phases. In phase 1, 20 consecutive patients undergoing routine phacoemulsification underwent biometry using both A‐scan ultrasonography and the Zeiss IOLMaster (ZIOLM). A single experienced optometrist refracted all patients 2 weeks after surgery. The errors between expected and achieved refraction were calculated and compared between the two methods. In phases 2 and 3, a further 22 and 20 patients, respectively, were recruited and only the ZIOLM was used for biometry. The manufacturer's suggested A‐constant was refined and the error between expected and achieved refraction was calculated.

Results:  In phase 1, the median unexpected error for the ZIOLM was +0.63 (interquartile range +0.368 to +1.015) and for A‐scan biometry was − 0.24 (interquartile range − 1.335 to +0.802). In phase 1 65% of patients' postoperative refractions were found to be within 1.0 D of emmetropia using the ZIOLM (55% using A‐scan biometry). Refinements to the A‐constant improved this to 95% by phase 3.

Conclusion:  An error was identified in IOL power estimation with the ZIOLM, when using the manufacturer's recommended A‐constant (recommended and previously optimized ultrasound A‐constant 118.0; ZIOLM optimized A‐constant 118.6). Serial modifications to the A‐constant were successful in reducing the unexpected error to well within the tolerance limits of published international standards.