bluuebunny/crossref_metadata_2025 huggingface dataset:
The intermediate disturbance hypothesis, refugia, and biodiversity in streams
Authors: Townsend Colin R. , Scarsbrook Mike R. , Dolédec Sylvain
Published: May 2010

The intermediate disturbance hypothesis has been influential in the development of ecological theory and has important practical implications for the maintenance of biodiversity but has received few rigorous tests. We tested the hypothesis that maximum taxon richness of macroinvertebrates will occur in communities subject to intermediate levels of disturbance at 54 stream sites that differed in the frequency and intensity of flood‐related episodes of bed movement. Our results support the intermediate disturbance hypothesis, with both highly mobile and relatively sedentary taxa conforming to the predicted bell‐shaped curve. Taxon richness was not related to habitat area (stream width), distance from the headwater, or the diversity of microhabitats (particle size categories) but was significantly and negatively related to the proportion of the substratum made up of small particles. Of all the factors measured, however, bed disturbance was by far the best at accounting for variation in taxonomic richness. We also quantified several kinds of potential refugia for invertebrates and found a positive relationship between richness and a refugia axis that combines amount of dead space with proportion of large substratum particles.
Self‐shading effect by radiance meters on upward radiance observed in coastal waters
Authors: Aas Eyvind , Korsbø Brith
Published: May 2010

The ratio between recorded and true upward radiance in coastal waters has been determined from observations at 445, 514, and 546 nm for solar zenith angles in the range 40–60°. The ratio follows an exponential function of KLR, where KL is the vertical attenuation coefficient of upward radiance and R is the instrument radius, for values of KLR up to 0.50. The observed relative self‐shading errors for an instrument radius of 7.5 cm in average optical conditions for the Oslofjord are in the range 0.04–0.18. They seem to differ by less than 0.07 from estimates based on Monte Carlo simulations by Gordon and Ding. The errors decrease with increasing solar zenith angle, but the observed errors are smaller than predicted by the Monte Carlo model. No variation in error with depth has been observed within the upper 2 m.
A study of metabolism‐influenced orientation in the diel vertical migration of marine dinoflagellates
Authors: Kamykowski Daniel , Yamazaki Hidekatsu
Published: May 2010

A biophysical model is used to compare the possible impacts of two different modes of cell orientation: taxis directed and metabolisminfluenced. The included submodels provide wind‐induced turbulent mixing in the Ekman layer based on wind forcing that randomly varies from day to day; a diurnal light cycle of sea‐surface photosynthetically active radiation (PAR) that is influenced by random cloud cover and that attenuates exponentially with depth; cell‐specific respiration and photosynthesis, with the latter incorporating high PAR photoinhibition, diel variability, and sun‐shade acclimation that varies from day‐to‐day; and cell motility with swimming speed that depends on gravity, temperature, and light intensity and with the two different orientation options. Taxis‐directed orientation is based on positive phototaxis during daylight and positive geotaxis at night. Metabolism‐influenced orientation uses a depth threshold to stop descent, sunrise or a cumulative respiration threshold approached at a rate based on the previous day’s PAR exposure to start ascent, a surface response or a photoinhibition threshold to stop ascent, and sunset or a cumulative photosynthesis threshold to start descent. The thresholds act as proxies for various cellular processes including nutrient uptake or metabolic synthesis that may be involved in orientation preference. Under the modeled conditions, cells using metabolism‐influenced regulation of swimming behavior exhibit more uniformly high cumulative primary production than those that do not.
Growth‐compensating phenomena in continuous cultures of Dunaliella tertiolecta limited simultaneously by light and nitrate
Authors: Sciandra Antoine , Gostan Jacques , Collos Yves , Descolas‐Gros Chantal , Leboulanger Christophe , Martin‐Jézéquel Véronique , Denis Michel , Lefèvre Dominique , Copin‐Montégut Claire , Avril Bernard
Published: May 2010

Two nitrogen‐limited continuous cultures of Dunaliella tertiolecta were grown on light/dark cycles. One was submitted to limiting photon flux density (PFD) and the other to nonlimiting PFD. The growth rate was identical in the two cultures despite the difference in the PFD conditions. Once equilibria were reached both cultures, the PFD were reversed to simulate a decrease and an increase in light conditions. A large suite of variables was measured to characterize the response of the cells, mainly through the interactions of carbon and nitrogen assimilation pathways. A decrease in irradiance led to a rapid decrease in algal biovolume; the biovolume‐based growth rate (µ) descended to levels lower than those estimated for cells of the light‐limited culture. An increase in irradiance rapidly led to an increase in µ, which attained values greater than those observed in high‐light cells of the other culture before the shift. For the two cultures before and after the shift, cell carbon and cell volume were strongly correlated, showing the same pattern of diel variations.

The specific C fixation rates (µC) of the two cultures before and after the light shift declined significantly during the light periods. Before the light shift, µC was paradoxically higher in the low light culture and could not be predicted only from the light levels. This suggests that some compensatory phenomena may occur during light and nitrogen limitations. Time variations of cell Chl a due to photoacclimation in both cultures were correlated with their N status. Similarly, the regulation of carboxylase activities (Rubisco) by the light levels was sensitive to the degree of N limitation. We found that nitrogen limitation has an overriding effect compared to light for the regulation of cell volume, C fixation and respiration rates, Chl a synthesis, electron transport system, and Rubisco activities. In cultures subjected to low irradiance, NO3− uptake rate decreased several hours into the dark phase, suggesting a time lag between the end of photosynthate production and the exhaustion of compounds necessary for dissolved inorganic nitrogen assimilation. The implications of these results concerning phytoplankton growth modeling in a variable environment are important because there are no existing models that correctly integrate the simultaneous effects of light and nitrogen on primary production. It is shown that the effects of these limitations were not additive in the range of light and N limitations tested in this experiment.
Phosphorus limitation of Daphnia growth: Is it real?
Authors: Urabe Jotaro , Clasen Jessica , Sterner Robert W.
Published: May 2010

The possibility of P limitation for zooplankton growth has many implications for understanding changes in production efficiency and feedback dynamics between consumers and resources. However, there have been no direct tests to determine whether the putative P limitation is real. To answer this question, we directly supplied inorganic P to Daphnia magna apart from food algae, Scenedesmus acutus, and then examined changes in body mass. During the period from birth to age 6 d, D. magna were fed on live algae for 19 h and placed in water of high inorganic P (4 mM: P treatment) for 5 h each day. We used P‐free water as a control treatment. Growth rate estimated from initial and final body mass during the 6‐d incubation was significantly larger in the P treatment than in the control treatment when Daphnia fed on P‐deficient algae, whereas a significant difference was not detected between the treatments for Daphnia fed on P‐sufficient algae (C : P atomic < 300). The results clearly demonstrate that Daphnia growth is in fact limited by P itself when they feed on P‐deficient algae.
UV‐absorbing compounds in the coral Pocillopora damicornis: Interactive effects of UV radiation, photosynthetically active radiation, and water flow
Authors: Jokiel Paul L. , Lesser Michael P. , Ondrusek Michael E.
Published: May 2010

A direct relationship exists between irradiance of solar ultraviolet (UV) radiation and concentration of UV‐absorbing compounds, know as mycosporine‐like amino acids (MAAs), in the Hawaiian reef coral Pocillopora damicornis. However, MAA concentration is also influenced by flow regime and the irradiance of photosynthetically active radiation (PAR). High irradiances of UV radiation in reef environments are correlated with high PAR and high water velocity, because all three parameters diminish exponentially with increased depth. This correlation can also be found along horizontal gradients on reefs. The clearest water is typically found on outer reefs growing in oceanic water. These ocean reefs typically experience high water velocities due to ocean swell when compared to the more turbid lagoon reefs exposed only to small wind‐driven waves. Flow‐modulated photosynthetic rate seems to be a major factor affecting the observed changes in MAA concentration when P. damicornis is grown under different flow regimes and identical irradiances of UV and PAR radiation. High PAR and high water velocity significantly enhance the effect of increased UV radiation on MAA concentration.
Preservation of community structure in death assemblages of deep‐water Caribbean reef corals
Authors: Pandolfi John M. , Greenstein Benjamin J.
Published: May 2010

An in situ survey of deep reef environments (20 and 30 m) was conducted to determine the degree to which the community structure of live reef coral assemblages was faithfully represented in the adjacent death assemblages accumulating on the sea floor. Relative abundance of species was significantly different between life and death assemblages, and zonation patterns (in species relative abundance, coral growth form, and diversity) present in the life assemblages showed both similarities and differences to those found in the death assemblages. The difference in species distribution patterns between life and death assemblages is shown by a striking growth form bias in the death assemblage: species with massive growth forms are underrepresented in the death assemblages in both environments, whereas branching, encursting, and plate growth forms are overrepresented in the death assemblages. Several factors may be involved in the life and death assemblage differences: greater degrees of time averaging than in previously studied reef settings, changes in the life assemblage such that death assemblages record previous life assemblages more faithfully than present ones, and undersampling of massive corals in death assemblages. Comparison of species richness and the Shannon‐Wiener index of diversity between life and death assemblages produced unexpected results. In general, death assemblages showed higher diversity than did life assemblages, more in accordance with previous studies of shelly molluscan faunas of temperature and tropical level‐bottom marine communities than with those of shallow‐water coral reef communities. Because our results differ from previous studies of community preservation in coral reefs, we recommend that paleoecological studies of aquatic ecosystems be accompanied by preservational assemblages from the same or similar environments. Our results point to the subtleties involved in interpreting coral death assemblages and suggest that these assemblages may contain as much or more information on recent changes in the living reef as they do on the future composition of the fossil reef assemblages.
Nitrogen elimination in two deep eutrophic lakes
Authors: Mengis Martin , Gächter René , Wehrli Bernhard , Bernasconi Stefano
Published: May 2010

Nitrogen elimination was investigated in two eutrophic Swiss lakes with different hypolimnetic oxygen conditions. Nitrogen burial was estimated from sediment‐trap and sediment‐core studies. Denitrification and NO3−‐ammonification rates were quantified with 15NO3− and acetylene incubation experiments and whole‐lake mass balances. The study confirmed earlier reports that the acetylene‐block technique yields denitrification rates that are systematically too low. Denitrification rates obtained from isotope tracer experiments were compatible with nitrogen consumption rates observed in flux chamber experiments and whole‐lake mass balances. The NO3−‐ammonification contributed <5% to the NO3− consumption rate in Lake Baldegg. Coupled nitrification‐denitrification seemed to be insignificant at the deepest station of Lake Baldegg. The comparison of in situ denitrification rates measured at the deepest site (4.3 mmol m−2 d−1) with the denitrification rate obtained from whole‐lake mass balances (6.1 mmolm−2 d−1) indicates that enhanced denitrification may be present in shallower sediments with a better supply of O2. Mass transfer coefficients for NO3− were similar in both lakes (21.7 and 21.4 m yr− ). The NO3− concentration seems to be a key parameter in determining denitrification rates.
The use of amides and other organic nitrogen sources by the phytoplankton Emiliania huxleyi
Authors: Palenik Brian , Henson Sarah E.
Published: May 2010

Although dissolved organic nitrogen (DON) is beginning to be seen as a potentially important nitrogen source for phytoplankton, much remains to be learned about its components and t heir utilization. Emiliania huxleyi, a cosmopolitan eukaryotic phytoplankton species abundant in oligotrophic oceans and during blooms in some coastal regions, was screened for use of various DON compounds. Hypoxanthine and other purines support the nickel‐dependent growth of most E. huxleyi strains. Acetamide and formamide but not longer chain aliphatic amides were found to be excellent nitrogen sources for growth; other phytoplankton were also found to utilize acetamide but not formamide. In E. huxleyi, small amides are transported into the cell followed by degradation to ammonia, possibly by amide‐specific enzymes. The related molecules hydroxyurea and thiourea were toxic to the cells and caused an increase in fluorescence consistent with blockage of photosystern II. This fluorescence increase was inhibited by urea and acetamide, suggesting transport of hydroxyurea, thiourea, urea, and acetamide by the same or closely related transporters.
Have we overlooked the importance of small phytoplankton in productive waters?
Authors: Carrick Hunter J. , Schelske Claire L.
Published: May 2010

The idea that phytoplankton size structure increases with elevated nutrient content in lakes may be inaccurate because phototrophic picoplankton (Ppico) abundance was not accounted for in studies that originally described this phenomenon. The biomass, composition, and production of an entire phytoplankton community was evaluated in hypereutrophic Lake Apopka, Florida (avg chlorophyll = 105 µg liter−1, n = 20) for 1 yr. Ppico cell abundances commonly exceed 107 cells ml−1, and size‐fractionated chlorophyll (<5 µm) and algal enumeration (cells <2 µm in size) indicate that pico‐size cyanobacteria contribute significantly to phytoplankton biomass throughout the year (avg 30%, n = 15), even though clogging of small pore‐sized filters used in chlorophyll fractionation studies led to underestimation of Ppico biomass estimates. Ppico production contributed nearly 30% (n = 8) to total phytoplankton production. The quantitative importance of Ppico in Lake Apopka and eight other hypereutrophic systems in Florida (avg 50% Chl <5 µm) indicates that Ppico can be important in waters of high nutrient content. The importance of small phytoplankton in productive waters may have been overlooked because (1) most studies focus on relatively pristine ecosystems, (2) some methodological constraints may impede studies in eutrophic environments (filtration artifacts), and (3) routine assessment of phytoplankton abundance rarely censuses all components of the community, including small algae.
Selectivity of Idothea chelipes (Crustacea: Isopoda) grazing on benthic microalgae
Authors: Sommer Ulrich
Published: May 2010

Periphyton grazing by the marine isopod Idothea chelipes was studied by exposing periphyton grown on glass slides to a gradient of grazer densities. An analysis of the algal growth rates and their relationships to grazer density revealed two groups of algae. The unicellular diatoms Licmophora ehrenbergii, Fragilaria tabulata, Navicula spp., Cocconeis costata, and the green alga Ulothrix implexa had high maximal growth rates (0.90–1.47 d−1) and suffered high grazing losses (0.41–0.68 d−1 per grazer ind.). The tube dwelling diatom Amphipleura rutilans and the cyanobacteria Lyngbya confervoides and Spirulina subsalsa had low maximal growth rates (0.38–0.81 d−1) and suffered only moderate grazing losses (0.10–0.27 d−1 per grazer ind.). The species of the first group seemed to be less strongly resource limited than did the species of the second group. Grazing by I. chelipes has the potential to drive succession from the well‐edible to the less edible periphyton species.
Virus à la sauce Yo‐Pro: Microwave enhanced staining for counting viruses by epifluorescence microscopy
Authors: Xenopoulos Marguerite A. , Bird David F.
Published: May 2010

A recently developed method for enumerating aquatic viruses (Yo‐Pro stained) was modified to reduce staining time and allow counting of fixed samples. Marine and freshwater virus samples to be enumerated were stained with the cyanine‐based dye Yo‐Pro‐1 by using microwave irradiation, which reduced incubation time from 48 h to 4 min. The modified method and the original protocol yielded similar viral estimates. Easier sample handling and the addition of fixed‐sample capability should allow epifluorescence counting of viruses to become a routine part of field studies of viral ecology.
Consequences of a Synechococcus bloom upon the optical properties of oceanic (case 1) waters
Authors: Morel André
Published: May 2010

A dense Synechococcus population has been observed in oceanic offshore waters (400 km from the Mauritanian coast) within the upper 30‐m‐thick layer. With cell counts >3 × 105 cells ml−1, about half (0.6) of the total Chl a concentration (1.25 mg m−3) was attributable to the cyanobacteria. The optical properties of this water body markedly differed from those of case 1 waters with the same Chl a concentration. The euphotic depth was diminished (by ~10 m on average) and the spectral attenuation coefficients for downwelling irradiance were increased (by 40– 60% in the green and blue parts of the spectrum); the absorption band characteristic of phycoerythrin was easily detected on filtered material, as well as within the in‐water light field and in the water‐leaving upward radiant flux. The amplitude of the departures of the actual optical properties from those predicted for normal case 1 waters are described and then analyzed through radiative transfer computations. The peculiar Chl‐specific absorption capabilities of Synechococcus (originating from the small size and the presence of phycobilins and zeaxanthin), rather than a significant increase in the bulk scattering properties, are at the origin of the deviations observed. The possibility of detecting such a particular algal bloom, through remote‐sensing techniques based on the ocean reflectance, requires a high radiometric sensitivity and dedicated spectral channels. If detection is feasible, quantifying the cyanobacterial biomass from satellite information remains a difficult task. The variability in the relative proportions of phycobilins and Chl a for these organisms impedes a quantitative assessement of their contribution to the total Chl biomass.
Factors controlling temporal variation in methyl mercury levels in sediment and water in a seasonally stratified lake
Authors: Regnell Olof , Ewald Göran , Lord Elsmari
Published: May 2010

Total mercury (total Hg) levels were low in the water (2.5–7.5 pM) and in the sediment (150–300 pmol g (DW)−1), indicating an absence of significant local sources of Hg. During summer stratification, methyl mercury (MeHg) levels increased below the thermocline, reaching 2.5 pM in the anoxic hypolimnion, whereas in the epilimnion levels remained low (0.25–0.6 pM) throughout the study period (late April–late October 1993). On October 27 (the last sampling date), the lake was totally mixed and MeHg in the entire water column had returned to low levels. Within the part of the basin turning anoxic during summer stratification, the MeHg levels in the surficial sediment (0–0.5 cm) and those in the overlying water were negatively correlated (r = −0.87, P < 0.05). Sediment MeHg decreased during summer stratification until August and then increased. In the sediment, total organic carbon was significantly correlated with total Hg (r = 0.86, P < 0.05), MeHg (r = 0.90, P < 0.01), and total Mn (r = 0.88, P < 0.01). A mechanism for the partitioning of MeHg between water and sediment is discussed, involving the Mn redox cycle. Budget calculations indicated that exchanges of a fixed amount of MeHg between the water and sediment could not explain the observed seasonal variation in MeHg levels. Other processes that may have contributed to the variation in MeHg levels in the sediment and water are methylation, demcthylation, mass dilution, and uptake of MeHg in the biota.
Free‐floating drifter for photochemical studies in the water column
Authors: Kieber David J. , Yocis Brian H. , Mopper Kenneth
Published: May 2010

A free‐floating drifter was designed to directly determine in situ photochemical production rates, photolysis rates, and light fluxes in seawater. This drifter consisted of six trays that were suspended in series from a single buoy line. The trays were constructed so that the attached quartz vessels, containing filtered seawater, were exposed to both downwelling and upwelling irradiation. The quartz vessels were sealed at both ends with ribbed TFE Teflon stoppers that permitted multiple subsampling without introduction of a headspace. The free‐floating drifter was used to study photochemical processes in antarctic waters. It performed well during 12–15‐h deployments, even in rough seas with sustained winds between 15 and 26 m s−1. Although not tested here, the drifter should perform equally well in the study of photochemical processes in freshwater environments.
Hydrogen Bonding Induced Supramolecular Self‐Assembly of Linear Doubly Discotic Triad Supermolecules
Authors: Miao Jianjun , Zhu Lei
Published: May 2010

A series of linear doubly discotic triad supermolecules based on a porphyrin (P) core and two triphenylene (Tp) arms linked by amide bonds are synthesized. The samples are denoted as P(Tp)2. Hydrogen bonding along the P stacks is the primary driving force for the supramolecular self‐assembly of P(Tp)2 triad supermolecules. Meanwhile, the degree of coupling between P and Tp disks also plays an important role. For samples with the spacer lengths longer than or similar to the alkyl chain lengths in the Tp arms, P and Tp are decoupled to a large degree. This decoupling result in non‐uniform tilt angles for P and Tp disks along both the a‐ and c‐axes. Therefore, large unit cells are observed with eight P(Tp)2 supermolecules per cell. For a sample with the spacer length much shorter than the alkyl chains in the Tp arms, P and Tp are strongly coupled. Therefore, both P and Tp have uniform tilt angles along the a‐ and c‐axes. A small unit cell is obtained with only one P(Tp)2 supermolecule per cell.
A comparison of simultaneous versus sequential presentation of novel foods in the treatment of food selectivity
Authors: VanDalen Kate H. , Penrod Becky
Published: May 2010

The present study extended the literature on feeding disorders by conducting a comparison of sequential and simultaneous food presentation in the treatment of food selectivity. In the simultaneous condition, a highly preferred food was presented in the same bite with a non‐preferred food (NPF), and during the sequential condition, a highly preferred food was delivered as a consequence for acceptance and consumption of NPFs. Generalization and maintenance of food consumption was assessed. Although results for two participants indicated that both presentation methods produced an increase in acceptance and consumption of NPFs when combined with an escape extinction procedure, anecdotal observations suggested that participants may have had a preference for eating foods in a sequential fashion. Copyright © 2010 John Wiley & Sons, Ltd.
Selective determination of human immunoglobulin G by flow‐injection chemiluminescence
Authors: Zhou Min , Wang Jiuchun , Ma Yongjun , Fang Yanjun , Chen Junhui , Chen Hui
Published: May 2010

A novel flow‐injection chemiluminescence method was developed for the selective determination of human immunoglobulin G (IgG) in the presence of thiomersal by changing the flow rates of peristaltic pump. The study was based on the independence and additivity of the CL signals of human IgG and thiomersal in the galangin–potassium permanganate–polyphosphoric acid system. In meantime, two equations relating to the concentrations of mixing solutions of human IgG and thiomersal vs the CL intensity were established and solved, on the basis of which the content of thiomersal included in samples was simultaneously determined too. The enhanced CL intensity was in proportion to concerntrations in the range 8.0 × 10−7 to 8.0 × 10−5 g/mL for human IgG and 1.0 × 10−7 to 2.0 × 10−6 g/mL for thiomersal with the detection limits of 5.0 × 10−7 g/mL for human IgG and 6.0 × 10−8 g/mL for thiomersal, respectively. The relative standard deviation for 1.0 × 10−5 g/mL human IgG was 0.8% and for 2.0 × 10−7 g/mL thiomersal it was 2.0% (n = 10). The proposed method was applied to determine three synthetic samples with recoveries of 91.5–109.5%. In addition, the possible chemiluminescence mechanisms are discussed as well. Copyright © 2010 John Wiley & Sons, Ltd.
Zinc(II)‐selective ratiometric fluorescent probe based on perylene bisimide derivative
Authors: Zhao Yingjie , Sun Juanjuan , Shi Zhiqiang , Pan Cuicui , Xu Maoyou
Published: May 2010

A fluorescent probe of N,N′‐biscyclohexyl‐1,7‐di(3‐pyridoxy)‐perylene‐3,4:9,10‐tetracarboxylic acid diimide has been synthesized, and exhibited excellent selectivity and sensitivity for Zn2+ over other competing biological cations. The Zn2+‐selective fluorescence blue‐shift and enhancing property in conjunction with a visible colorimetric change from orange to green could be observed. With favorable photophysical properties in the visible region, the perylene bisimide derivatives remarkably improved the performance of the probe. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis, characterization and luminescent properties of lanthanide complexes with an unsymmetrical tripodal ligand
Authors: Yan Zhen‐Zhong , Dai Guo‐Liang , Liang Hua‐Ding , Lin Yong‐Qiang
Published: May 2010

Solid complexes of lanthanide nitrates with an novel unsymmetrical tripodal ligand, butyl‐N,N‐bis[(2′‐benzylaminofomyl)phenoxyl)ethyl]‐amine (L) have been synthesized and characterized by elemental analysis, infrared spectra and molar conductivity measurements. At the same time, the luminescent properties of the Sm(III), Eu(III), Tb(III) and Dy(III) nitrate complexes in solid state were also investigated. Under the excitation of UV light, these complexes exhibited characteristic emission of central metal ions. Copyright © 2010 John Wiley & Sons, Ltd.
Right hepatectomy by the anterior method with liver hanging versus conventional approach for large hepatocellular carcinomas
Authors: Wu T-J , Wang F , Lin Y-S , Chan K-M , Yu M-C , Lee W-C
Published: May 2010

Background

The aim was to compare short-term results of right hepatectomy using the anterior approach (AA) and liver hanging manoeuvre with the conventional approach (CA) for large hepatocellular carcinoma (HCC).

Methods

This was a retrospective review of 71 consecutive patients with HCC at least 5 cm in diameter who underwent curative right hepatectomy using either the AA with the liver hanging manoeuvre (33) or the CA (38) between January 2004 and December 2008. Clinical data, operative results and survival outcomes were analysed.

Results

The groups had similar clinical, laboratory and pathological parameters. The AA group had larger tumours than the CA group (P = 0·039), but comparable grade and stage distribution. The operative results were similar except for an increased blood transfusion requirement with the conventional procedure (P = 0·001). The AA group had a lower recurrence rate (P = 0·003) and better disease-free survival (DFS) (P = 0·001) than the CA group, but overall survival rates were not significantly different (P = 0·091). Presence of tumour encapsulation, absence of tumour microvascular invasion and AA were predictive of DFS, whereas tumour stage was the only independent predictor of overall survival.

Conclusion

The AA right hepatectomy with liver hanging manoeuvre for large HCC is associated with reduced blood transfusion requirement and lower recurrence rates in the short term.
Randomized clinical trial of laparoscopic versus open left colonic resection
Authors: Braga M , Frasson M , Zuliani W , Vignali A , Pecorelli N , Di Carlo V
Published: May 2010

Background

The main aim of this study was to compare short-term results and long-term outcomes of patients undergoing laparoscopic versus open left colonic resection.

Methods

Between February 2000 and December 2004, all adult patients undergoing elective left colonic resection were assessed for eligibility to the study. The protocol for postoperative care was the same in both groups. Cost–benefit analysis was based on hospital costs. Quality of life, long-term morbidity and 5-year survival were also evaluated.

Results

Some 268 patients undergoing left colonic resection were assigned randomly to the laparoscopic (n = 134) or open (n = 134) approach. The short-term morbidity rate was 20·1 per cent in the open group and 11·9 per cent in the laparoscopic group (P = 0·094). Hospital stay was longer in the open group (8·7 versus 7·0 days for the laparoscopic approach; P = 0·002). Cost–benefit analysis showed an additional cost of €66 per patient randomly allocated to the laparoscopic group. Quality of life was significantly improved in the laparoscopic group 6 months after surgery, but no difference was found subsequently. The long-term morbidity rate was 11·9 per cent in the open group and 7·5 per cent in the laparoscopic group (P = 0·413). The 5-year survival rate of patients with cancer was 66 and 72 per cent for open and laparoscopic groups respectively (P = 0·321).

Conclusion

Laparoscopic left colonic resection resulted in an earlier recovery after surgery. As cost–benefit analysis and long-term follow-up showed similar results, the laparoscopic approach should be preferred to open surgery. Registration number: NCT00894725 (http://clinicaltrials.gov).
Measuring performance in clinical breast examination
Authors: Wishart G C , Warwick J , Pitsinis V , Duffy S , Britton P D
Published: May 2010

Background

Clinical breast examination (CBE) remains an essential part of triple assessment of breast lumps, but to date there are no performance measures for clinicians using this technique. The aim of this retrospective audit was to compare the performance and accuracy of CBE to identify key indicators that could be used to monitor performance prospectively.

Methods

Clinical examination findings (E1, normal, to E5, malignant) for 16 585 patients who had CBE as part of triple assessment were obtained from electronic medical records. The performance of CBE, by age group, mammographic density and clinician, was assessed by calculating the sensitivity, specificity and area under the receiver operating characteristic (ROC) curve.

Results

There was marked variation in sensitivity between clinicians (range 44·6–65·9 per cent). There was a strong downward trend in the percentage classified as E5 as sensitivity for breast cancer detection decreased, and a corresponding strong downward trend in the proportion of E4 and E5 cancers classified as E5. Both of these measures could be used as indicators to monitor CBE performance.

Conclusion

The performance measures outlined here could help to identify clinicians who have a lower sensitivity for CBE and who may therefore require feedback and further training.
Judging intoxication
Authors: Rubenzer Steve
Published: May 2010

Judgments of whether a person is intoxicated by alcohol are important in a number of civil and law enforcement settings. This paper reviews how well people are able to make such judgments, the evidence for individual signs of intoxication, several structured rating techniques, and the use of sobriety tests. It is concluded that observers relying on common‐sense clues of intoxication have limited ability to assess the blood alcohol concentration (BAC) levels of strangers, particularly below .10%. This generalization holds across professions that might be expected to show greater accuracy. Structured assessment instruments based on observable signs have shown promise but are confounded by the wide variations between casual social drinkers and those that have obtained a high level of tolerance. Among sobriety tests, only NHTSA's Standardized Field Sobriety Tests (SFSTs) have substantial, but seriously flawed, research support. Assessing the sobriety of strangers in the low to moderate BAC ranges without resort to chemical tests remains a daunting task. Copyright © 2010 John Wiley & Sons, Ltd.
An efficient nonlinear programming strategy for PCA models with incomplete data sets
Authors: de la Fuente Rodrigo López‐Negrete , García‐Muñoz Salvador , Biegler Lorenz T.
Published: May 2010

Processing plants can produce large amounts of data that process engineers use for analysis, monitoring, or control. Principal component analysis (PCA) is well suited to analyze large amounts of (possibly) correlated data, and for reducing the dimensionality of the variable space. Failing online sensors, lost historical data, or missing experiments can lead to data sets that have missing values where the current methods for obtaining the PCA model parameters may give questionable results due to the properties of the estimated parameters. This paper proposes a method based on nonlinear programming (NLP) techniques to obtain the parameters of PCA models in the presence of incomplete data sets. We show the relationship that exists between the nonlinear iterative partial least squares (NIPALS) algorithm and the optimality conditions of the squared residuals minimization problem, and how this leads to the modified NIPALS used for the missing value problem. Moreover, we compare the current NIPALS‐based methods with the proposed NLP with a simulation example and an industrial case study, and show how the latter is better suited when there are large amounts of missing values. The solutions obtained with the NLP and the iterative algorithm (IA) are very similar. However when using the NLP‐based method, the loadings and scores are guaranteed to be orthogonal, and the scores will have zero mean. The latter is emphasized in the industrial case study. Also, with the industrial data used here we are able to show that the models obtained with the NLP were easier to interpret. Moreover, when using the NLP many fewer iterations were required to obtain them. Copyright © 2010 John Wiley & Sons, Ltd.
ChemInform Abstract: An ab‐initio Study of the Role of Ione Pairs in the Structure and Insulator‐Metal Transition in SnO and PbO
Authors: Raulot Jean‐Marc , Baldinozzi Gianguido , Seshadri Ram , Cortona Pietro
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Electronic Properties of the Silver—Silver Chloride Cluster Interface.
Authors: Glaus Stephan , Calzaferri Gion , Hoffmann Roald
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Gallium Flux Synthesis of Tb3‐xC2Si8(B12)3: A Novel Quaternary Boron‐Rich Phase Containing B12 Icosahedra.
Authors: Salvador James R. , Bilc Daniel , Mahanti S. D. , Kanatzidis Mercouri G.
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Experimental and Theoretical Study on the Structure of Nitramide H2NNO2.
Authors: Haeussler Angelika , Klapoetke Thomas M. , Piotrowski Holger
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Bismuth Octaborate, Bi2B8O15.
Authors: Teng Bing , Yu Wen Tao , Wang Ji Yang , Cheng Xiu Feng , Dong Sheng Ming , Liu Yao Gang
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Cubane with a Handle: [{In3As4Nb}‐As]7‐ in Cs7NbIn3As5.
Authors: Gascoin Franck , Sevov Slavi C.
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Sensitized Luminescence of Trivalent Europium by Three‐Dimensionally Arranged Anatase Nanocrystals in Mesostructured Titania Thin Films.
Authors: Frindell Karen L. , Bartl Michael H. , Popitsch Alois , Stucky Galen D.
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Ferromagnetism in One‐Dimensional Monatomic Metal Chains.
Authors: Gambardella P. , Dallmeyer A. , Maiti K. , Malagoli M. C. , Eberhardt W. , Kern K. , Carbone C.
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Phase Equilibria in the Sm—Zr—Sb System at 1070 K.
Authors: Morozkin A. V.
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: CsMBi3Te6 and CsM2Bi3Te7 (M: Pb, Sn): New Thermoelectric Compounds with Low‐Dimensional Structures.
Authors: Hsu Kuei‐Fang , Chung Duck‐Young , Lal Sangeeta , Mrotzek Antje , Kyratsi Theodora , Hogan Tim , Kanatzidis Mercouri G.
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Electrochemical Behavior of Hydrazonates in Protic and Aprotic Medium.
Authors: Saied T. , Benkhoud M. L. , Boujlel K.
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Monobenzylethers of (R,R)‐1,2‐Diphenylethane‐1,2‐diol as a Possible Alternative to Cyclohexyl‐Based Chiral Auxiliaries in the Stereoselective Reduction of α‐Ketoesters.
Authors: Scafato Patrizia , Leo Laura , Superchi Stefano , Rosini Carlo
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Reactions of Trimethylsilyl‐Derived Iodohydrins with Electron‐Rich π‐Systems.
Authors: Ishai Eti , Shamai Sarit , Feit Ben‐Ami
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Enaminones in Organic Synthesis: A Novel Synthesis of 1,3,5‐Trisubstituted Benzene Derivatives and of 2‐Substituted‐5‐aroylpyridines.
Authors: Abdel‐Khalik Mervat Mohammed , Elnagdi Mohamed Hilmy
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Control of the Reaction Between 2‐Aminobenzothiazoles and Mannich Bases. Synthesis of Pyrido[2,1‐b][1,3]benzothiazoles versus [1,3]Benzothiazolo[2,3‐b]quinazolines.
Authors: Quiroga Jairo , Hernandez Pedro , Insuasty Braulio , Abonia Rodrigo , Cobo Justo , Sanchez Adolfo , Nogueras Manuel , Low John N.
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Reversible C↔N Migration of the Ethoxycarbonyl Group in the Reactions of Pyridinium and Isoquinolinium Ylides Derived from Malonic Ester with Isocyanates.
Authors: Gololobov Yuri G. , Dovgan Olga V. , Golding Igor R. , Petrovskii Pavel V. , Garbuzova Irina A.
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Preparation of Hydroperoxides by N‐Hydroxyphthalimide‐Catalyzed Aerobic Oxidation of Alkylbenzenes and Hydroaromatic Compounds and Its Application.
Authors: Fukuda Osamu , Sakaguchi Satoshi , Ishii Yasutaka
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Thionation of Bisindole Derivatives with P4S10 or Elemental Sulfur.
Authors: Janosik Tomasz , Bergman Jan , Stensland Birgitta , Staalhandske Claes
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Conjugate Addition of Amines to α,β‐Enones Promoted by CeCl3×7H2O—NaI System Supported in Silica Gel.
Authors: Bartoli Giuseppe , Bosco Marcella , Marcantoni Enrico , Petrini Marino , Sambri Letizia , Torregiani Elisabetta
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Studies on Organosilicon Chemistry. Part 156. Lewis Acid Catalyzed Reductive Etherification of Carbonyl Compounds with Alkoxyhydrosilanes.
Authors: Miura Katsukiyo , Ootsuka Kazunori , Suda Shuntaro , Nishikori Hisashi , Hosomi Akira
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of the Four Stereoisomers of 1,1,1‐Trifluorobutane‐2,3‐diol.
Authors: Morelli Carlo F. , Speranza Giovanna , Duri Lavinia , Manitto Paolo
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Asymmetric Synthesis of Protected 1,2‐Amino Alcohols Using tert‐Butanesulfinyl Aldimines and Ketimines.
Authors: Tang Tony P. , Volkman Steven K. , Ellman Jonathan A.
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A One‐Pot Radical Addition/Fragmentation Route to Ketones and Esters.
Authors: Roepel Michael G.
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Diastereoselective Synthesis of Enantiomerically Pure 1,2‐Disubstituted Cyclopropanols from Allylic Sulfones.
Authors: Diez D. , Garcia P. , Pacheco M. P. , Marcos I. S. , Garrido N. M. , Basabe P. , Urones J. G.
Published: May 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.