bluuebunny/crossref_metadata_2025 huggingface dataset:
Constructive controversy, the Vroom‐Yetton model, and managerial decision‐making
Authors: Tjosvold Dean , Wedley William C. , Field Richard H. G.
Published: July 2007

Empirical tests have indicated that following the Vroom‐Yetton Normative Model of leadership predicts reliably to successful managerial decision‐making. However, it does not consider the kind of social interaction among decision makers. Recent experiments have demonstrated that controversy constructively discussed can facilitate decision‐making. To see whether constructive controversy can supplement the Vroom‐Yetton model, 58 managers enrolled in an executive‐level MBA programme described a successful and unsuccessful decision‐making experience by answering the Vroom‐Yetton questions and by indicating the extent those involved in making the decision experienced constructive controversy. Results indicate that both the Vroom‐Yetton model and constructive controversy are significantly related to successful decision‐making. A regression analysis indicated that constructive controversy accounted for 45 per cent of the variance of decision success whereas the Vroom‐Yetton model accounted for 5 per cent. While the Vroom‐Yetton model is useful at the preplanning stage for choosing a decision style, much greater contribution is provided by constructive discussions of opposing opinions when actually generating the decision.
Work schedule flexibility and family life
Authors: Staines Graham L. , Pleck Joseph H.
Published: July 2007

This paper explores the implications of work schedule flexibility for family life. Based on data from the 1977 Quality of Employment Survey, it demonstrates that flexibility of work schedules moderates the effects of nonstandard work schedules on family life. That is, nonstandard work schedules tend to have a less negative association with the quality of family life when accompanied by a high level of schedule flexibility. The paper further demonstrates that this tendency of flexibility to act as a buffer against the negative effects of nonstandard work schedules on family life is more pronounced among working women than working men.
Evaluation of alternative models of commitments and job attitudes of professionals
Authors: Lachman Ran , Aranya Nissim
Published: July 2007

Different and sometimes contradictory assumptions can be found in the literature about the relationships between the commitments of professionals to their profession and to the employing organization, and the consequences of these relationships for other work attitudes. Two of the basic alternative theoretical formulations are examined and their viability tested on a sample of 1206 accountants. One formulation assumes inconsistency between commitments leading to a commitment dilemma, the other assumes congruity between them. The findings point at the latter formulation as the more viable one, and suggests minor modifications in it to improve its fit with the data. The results demonstrate the need to compare competing models in order to increase theoretical clarity and consistency.
Computerized offices in Canada and the United States: Investigating dispositional similarities and differences
Authors: Gattiker Urs E. , Nelligan Todd W.
Published: July 2007

A scale measuring computer dispositions was used in order to examine whether computerization of work affects employees similarly or differently in Canada and the United States. The study explores the possibility that employees may differ intraculturally, that is, according to gender, hierarchical level in the firm, and whether they work with intelligent work‐stations or main‐frame terminals. The data indicates that intracultural differences are apparent according to type of computer used, gender, and hierarchical level of the respondents. What concerned U.S. female respondents about computer‐mediated work did not necessarily apply to their Canadian counterparts.
A comparison of different conceptualizations of perceived alternatives in turnover research
Authors: Griffeth Rodger W. , Hom Peter W.
Published: July 2007

The present study compared the relative predictive validity of different formulations of perceived alternatives in turnover models. These formulations varied according to different levels of specificity and proximity to turnover criteria and were examined within the framework of the Mobley turnover theory (1977; Mobley, Griffeth, Hand and Meglino, 1979). A sample of 244 nurses was administered a survey assessing determinants of turnover. Six months later voluntary turnover data were collected. While intention to quit and turnover were significantly predicted by their antecedents, the results were not entirely supportive of Mobley's theory. Methodological and theoretical reasons were advanced for the inconsistent findings.
The impact of interpersonal environment on burnout and organizational commitment
Authors: Leiter Michael P. , Maslach Christina
Published: July 2007

Organizational commitment and burnout were related to interpersonal relationships of nurses in a small general hospital. Regular communication contacts among personnel were differentiated as supervisor or coworker contact, and these categories were further differentiated into pleasant and unpleasant contacts. The results were consistent with a view of burnout in which emotional exhaustion leads to greater depersonalization which subsequently leads to diminished personal accomplishment. Interpersonal contact with personnel in the organization was related to the development of burnout at each stage. Patterns of pleasant and unpleasant contacts with supervisors and coworkers were related to the three aspects of burnout in a distinct manner. High burnout was related to diminished organizational commitment, which was also related to aspects of the interpersonal environment of the organization. The results are discussed in the context of a comprehensive approach to psychological adjustment to a worksetting.
Proteomic analysis of serum, plasma, and lymph for the identification of biomarkers
Authors: Meng Zhaojing , Veenstra Timothy D.
Published: July 2007

Probably no topic has generated more excitement in the world of proteomics than the search for biomarkers. This excitement has been generated by two realities: the constant need for better biomarkers that can be used for disease diagnosis and prognosis, and the recent developments in proteomic technologies that are capable of scanning the individual proteins within varying complex clinical samples. Ideally a biomarker would be assayable from a noninvasively collected sample, therefore, much of the focus in proteomics has been on the analysis of biofluids such as serum, plasma, urine, cerebrospinal fluid, lymph, etc. While the discovery of biomarkers has been elusive, there have been many advances made in the understanding of the proteome content of various biofluids, and in the technologies used for their analysis, that continues to point the research community toward new methods for achieving the ultimate goal of identifying novel disease‐specific biomarkers. In this review, we will describe and discuss many of the proteomic approaches taken in an attempt to find novel biomarkers in serum, plasma, and lymph.
Prenatal exposure to cocaine is associated with increased number of spine synapses in rat prelimbic cortex
Authors: Morrow Bret A. , Hajszan Tibor , Leranth Csaba , Elsworth John D. , Roth Robert H.
Published: July 2007

Prenatal exposure to cocaine has been associated with cognitive deficits in children and in animal models. An excess activation of pyramidal neurons in the prefrontal cortex has been proposed as a potential cause for these deficits based on previous studies. The goal of this study was to determine if prenatal exposure to cocaine was associated with an increase in the number of excitatory synapses on dendritic spines in layer II/III of the prelimbic cortex. Frontal cortex of young adult male and female rats, exposed to either saline or cocaine (3 mg/kg i.e., twice a day, embryonic day 10–20), were examined using electron microscopy and the number of asymmetric spines synapses were estimated using the physical disector method. Both male and female rats prenatally exposed to cocaine had about twice as many synapses on dendritic spines as the prenatal saline controls. The increase in number of excitatory synaptic inputs associated with prenatal cocaine exposure could contribute to the increased neuronal activation and cognitive deficits noted. Synapse 61:862–865, 2007. © 2007 Wiley‐Liss, Inc.
Ejection fraction and blood pressure are important and interactive predictors of 4‐week mortality in severe acute heart failure
Authors: Adamopoulos Chris , Zannad Faiez , Fay Renaud , Mebazaa Alexandre , Cohen‐Solal Alain , Guize Louis , Juillière Yves , Alla François
Published: July 2007

Background:

In acute heart failure syndromes (AHFS), the prognostic value of left ventricular ejection fraction (LVEF), although widely accepted, has been recently challenged. In contrast, blood pressure is increasingly gaining ground over LVEF as predictor of mortality. Therefore, it is not clear whether both LVEF and mean arterial pressure (MAP) are independent risk factors in patients with AHFS.

Methods and results:

The EFICA study enrolled 581 AHFS patients admitted to 60 CCU/ICUs. Survival at 4 weeks was analyzed for all cases with echocardiographic LVEF available on admission (n%355).

Four‐week mortality was 23%. Multivariable analysis identified lower LVEF, lower MAP and serum creatinine >1.5 mg/dl as independent correlates of mortality (respectively, OR: 1.27 per 10% decrease, CI: 1.05–1.53, p%0.012; OR: 1.30 per 10 mmHg decrease, CI: 1.15–1.48, p<0.0001; OR: 2.84, CI: 1.64–4.93, p%0.0002).

LVEF interacted significantly with MAP (p<0.0001) and the subgroup analysis showed that reduced LVEF was a strong risk factor in patients with MAP ≤90 mmHg (OR: 2.73, CI: 1.23–5.98, p%0.01) but did not reach statistical significance in patients with MAP >90 mmHg.

Conclusions:

Both LVEF and MAP are important predictors of death in severe AHFS. LVEF can provide additional prognostic information on top of MAP but mainly in patients with low MAP (≤90 mmHg) at admission.
Health of urban Ghanaian women as identified by the Women's Health Study of Accra
Authors: Hill A.G. , Darko R. , Seffah J. , Adanu R.M.K. , Anarfi J.K. , Duda R.B.
Published: July 2007

Objective

The purpose of the Women's Health Study of Accra was to provide an assessment of the prevalence of communicable and non‐communicable illnesses.

Method

This was a prospective, community‐based study that included an interview for medical illnesses, a comprehensive physical examination, and laboratory testing. A total of 1328 women were examined at Korle Bu Teaching Hospital, University of Ghana.

Results

Prevalent conditions included poor vision (66.8%), malaria (48.7%), pain (42.8%), poor dentition (41.6%), hypertension (40.2%), obesity (34.7%), arthritis (27.1%), chronic back pain (19.4%), abnormal rectal (16.0%) and pelvic examinations (12.7%), HIV in women age 24–29 (8.3%), and hypercholesterolemia (22.7%). Increasing age, lack of formal education, and low‐income adversely affected health conditions.

Conclusion

The high prevalence of preventable illnesses in this expanding urban population indicates that the health care services are obligated to develop and provide screening, preventive strategies and treatment for both general health and gynecologic health conditions.
Pre-LGM open-water conditions south of the Drygalski Ice Tongue, Ross Sea, Antarctica
Authors: Finocchiaro Furio , Baroni Carlo , Colizza Ester , Ivaldi Roberta
Published: July 2007

A marine sediment core collected from the Nordenskjold Basin, to the south of the Drygalski Ice Tongue, provides new sedimentological and chronological data for reconstructing the Pleistocene glacial history and palaeoenvironmental evolution of Victoria Land. The core consists of an over consolidated biogenic mud covered with glacial diamicton; Holocene diatomaceous mud lies on top of the sequence. Radiocarbon dates of the acid insoluble organic matter indicate a pre-Last Glacial Maximum age (>24kyr) for the biogenic mud at the base of the sequence. From this we can presume that at least this portion of the western Ross Sea was deglaciated during Marine Isotope Stage 3 and enjoyed open marine conditions. Our results are consistent with recent findings of pre-Holocene raised beaches at Cape Ross and in the Terra Nova Bay area.
Plastic flow of two‐phase marbles
Authors: Renner Jörg , Siddiqi Gunter , Evans Brian
Published: July 2007

To quantify the effect of rigid inclusions on the flow behavior of a creeping matrix, we fabricated a suite of two‐phase marbles by hot isostatically pressing mixtures of calcite and quartz powders and subsequently deformed these synthetic rocks at 300 MPa confining pressure, up to 100 MPa pore pressure, temperatures ranging from 873 to 1073 K, strain rates and stresses ranging from ∼10−7s−1to ∼10−3s−1and ∼4 MPa to 190 MPa, respectively. In constant displacement rate tests performed to axial strains of up to about 30%, we observed deformation at approximately constant stress for samples with 20% or less quartz. Even small additions of second phase significantly strengthen the aggregate, although the magnitude of the strengthening varies significantly with temperature and imposed strain rate. Investigation of the microstructure of starting samples reveals that initial porosity directly varies with quartz content and that matrix grain size inversely varies with the amount of second phase. Strength decreases modestly with increasing porosity, and consequently, strength increases as the samples compact. The effect of matrix grain size on the aggregate strength depends on the deformation conditions. The majority of tests exhibit an inverse relation between strength and matrix grain size (i.e., similar to a Hall‐Petch relation), but fine‐grained samples deformed at the highest temperatures exhibit decreasing strength with decreasing grain size. The addition of the quartz particles seems to result in both structural strengthening owing to decreased grain size and to transfer of load from the flowing matrix to the rigid quartz particles.
North Atlantic climate and deep‐ocean flow speed changes during the last 230 years
Authors: Boessenkool K. P. , Hall I. R. , Elderfield H. , Yashayaev I.
Published: July 2007

Variations in the near‐bottom flow speed of Iceland‐Scotland Overflow Water (ISOW) are documented in a 230‐year‐long deep‐sea sediment record from the eastern flank of Reykjanes Ridge in the subpolar North Atlantic at (sub)decadal time scales. For recent decades, the ISOW palaeocurrent reconstructions show similarities with observational hydrographic data. Furthermore, recent ISOW flow changes fall mostly within the range of its variability of the past 230 years. The record also reveals a hitherto unrecognized coupling of deep flow speeds in the subpolar North Atlantic with the North Atlantic Oscillation (NAO) index, with more (less) vigorous ISOW flow during negative (positive) phases of the NAO. Our results suggest that the changes in ISOW vigor are largely controlled by the transport and characteristics of Labrador Sea Water rather than variations in the overflow itself, with implications for the meridional overturning of the Atlantic Ocean and climate.
Observational evidence for a Southern Hemisphere oceanic supergyre
Authors: Ridgway K. R. , Dunn J. R.
Published: July 2007

A high‐resolution hydrographic atlas resolves the narrow boundary flow of the western Pacific gyre and its pathway around Tasmania, southern Australia and into the Indian Ocean basin. This confirms recent model descriptions of a Southern Hemisphere ‘supergyre’, a nested system of subtropical gyres. The observations show that the gyre flow is squeezed into a narrow band between Tasmania and the Antarctic Circumpolar Current. The residue of East Australian Current transport turns westward around Tasmania and ‘leaks’ into the Indian Ocean. While there is also a limited form of gyre connection between the Indian and Atlantic systems south of Africa, with a mean outflow of Agulhas Current water into the Atlantic basin, these gyre circulations remain far more discrete. The gyre coupling and the East Australian Current in particular, provide the mechanism by which Sub Antarctic Mode Water and Antarctic Intermediate Water are distributed between the ocean basins.
Saturated magnetic fields of Weibel instabilities in ultraintense laser-plasma interactions
Authors: Okada T. , Ogawa K.
Published: July 2007

The interaction of ultraintense laser pulses with plasmas is studied by theory as well as three-dimensional particle-in-cell simulations. Self-generated magnetic fields are observed in the plasma target owing to the Weibel instability. The growth rates of the self-generated magnetic fields and the saturated magnetic fields in our theory are in good agreement with the results of our simulations. It is found that the saturated magnetic fields of Weibel instabilities are determined by the laser intensity and the plasma density.
Dynamics of viscoelastic fluid filaments in microfluidic devices
Authors: Steinhaus Benjamin , Shen Amy Q. , Sureshkumar Radhakrishna
Published: July 2007

The effects of fluid elasticity and channel dimension on polymeric droplet formation in the presence of a flowing continuous Newtonian phase are investigated systematically by using different molecular weight (MW) poly(ethylene oxide) (PEO) solutions and varying microchannel dimensions with constant orifice width (w) to depth (h) ratio (w∕h=1∕2) and w=25μm, 50μm, 100μm, and 1mm. The flow rate is varied so that the mean shear rate is practically identical for all cases considered. Relevant times scales include inertia-capillary Rayleigh time τR=(Rmax3ρ∕σ)1∕2, viscocapillary Tomotika time τT=η0Rmax∕σ, and the polymer relaxation time λ, where ρ is the fluid density of the dispersed phase, σ is the interfacial tension, η0 is the zero shear viscosity of the dispersed polymer phase, and Rmax is the maximum filament radius. Dimensionless numbers include the elasticity number E=λν∕Rmax2, elastocapillary number Ec=λ∕τT, and Deborah number, De=λ∕τR, where ν=η0∕ρ is the kinematic shear viscosity of the fluids. Experiments show that higher MW Boger fluids possessing longer relaxation times and larger extensional viscosities exhibit longer thread lengths and longer pinch-off times (tp). The polymer filament dynamics are controlled primarily by an elastocapillary mechanism with increasing elasticity effect at smaller length scales (larger E and Ec). However, with weaker elastic effects (i.e., larger w and lower MW), pinch-off is initiated by inertia-capillary mechanisms, followed by an elastocapillary regime. A high degree of correlation exists between the dimensionless pinch-off times and the elasticity numbers. We also observe that higher elasticity number E yields smaller effective λ. Based on the estimates of polymer scission probabilities predicted by Brownian dynamics simulations for uniaxial extensional flows, polymer chain scission is likely to occur for ultrasmall orifices and high MW fluids, yielding smaller λ. Finally, the inhibition of bead-on-a-string formation is observed only for flows with large Deborah number (De⪢1).
Nonlinear oscillations and collapse of elongated bubbles subject to weak viscous effects: Effect of internal overpressure
Authors: Tsiglifis Kostas , Pelekasis Nikos A.
Published: July 2007

The details of nonlinear oscillations and collapse of elongated bubbles, subject to large internal overpressure, are studied by a boundary integral method. Weak viscous effects on the liquid side are accounted for by integrating the equations of motion across the boundary layer that is formed adjacent to the interface. For relatively large bubbles with initial radius R0 on the order of millimeters, PSt=PSt′∕(2σ∕R0)∼300 and Oh=μ∕(σR0ρ)1∕2∼200, and an almost spherical initial shape, S∼1, Rayleigh-Taylor instability prevails and the bubble breaks up as a result of growth of higher modes and the development of regions of very small radius of curvature; σ, ρ, μ, and PSt′ denote the surface tension, density, viscosity, and dimensional static pressure in the host liquid while S is the ratio between the length of the minor semiaxis of the bubble, taken as an axisymmetric ellipsoid, and its equivalent radius R0. For finite initial elongations, 0.5⩽S<1, the bubble collapses either via two jets that counterpropagate along the axis of symmetry and eventually coalesce at the equatorial plane, or in the form of a sink flow approaching the center of the bubble along the equatorial plane. This pattern persists for the above range of initial elongations examined and large internal overpressure amplitudes, εB⩾1, irrespective of Oh. It is largely due to the phase in the growth of the second Legendre mode during the after-bounce of the oscillating bubble, during which it acquires large enough positive accelerations for collapse to take place. For smaller bubbles with initial radius on the order of micrometers, PSt∼4 and Oh∼20, and small initial elongations, 0.75<S⩽1, viscosity counteracts P2 growth and subsequent jet motion, thus giving rise to a critical value of Oh−1 below which the bubble eventually returns to its equilibrium spherical shape, whereas above it collapse via jet impact or sink flow is obtained. For moderate elongations, 0.5⩽S⩽0.75, and large overpressures, εB⩾0.2, jet propagation and impact along the axis of symmetry prevails irrespective of Oh. For very large elongations, S<0.5, and above a certain threshold value of Oh the counterpropagating jets pinch the contracting bubble sidewalls in an off-centered fashion.
Attenuated herpes simplex virus 1 blocks arterial apoptosis and intimal hyperplasia induced by balloon angioplasty and reduced blood flow
Authors: Skelly Christopher L. , Chandiwal Amito , Vosicky James E. , Weichselbaum Ralph R. , Roizman Bernard
Published: July 2007

Injury caused by distention of the arterial wall by balloon angioplasty can result in apoptosis and vascular smooth muscle cell proliferation. Here, we report that a brief exposure of the arterial lumen to a genetically engineered, attenuated herpes simplex virus 1 blocks activation of caspase 3-dependent apoptosis and MAPK-dependent cell proliferation induced by carotid artery balloon angioplasty and ligation to reduce blood flow. The procedure enables the restoration of the endothelial cell layer lining the lumen and prevents neointimal hyperplasia and restenosis. These findings have a broad application in prevention of balloon angioplasty-induced restenosis.
Evaluating the impact of gillnet ghost fishing using a computational analysis of the geometry of fishing gear
Authors: Takagi Tsutomu , Shimizu Takashi , Korte Holger
Published: July 2007

Takagi, T., Shimizu, T., and Korte, H. 2007. Evaluating the impact of gillnet ghost fishing using a computational analysis of the geometry of fishing gear. – ICES Journal of Marine Science, 64: 1517–1524. We developed a net shape and load analysis system (NaLA) that can estimate the three-dimensional shape of fishing gear underwater computationally. This paper introduces the latest version of the numerical model of the NaLA. Previously, NaLA was used to estimate the net geometries and internal forces of some fishing gear, demonstrating its general versatility. However, the ultimate goal of our study has been to learn about the impact of fishing and the capture process from a physical perspective, not simply to develop elemental technologies for gear design. Accurate, quantitative evaluation of fishing gear performance from a physical perspective can be used to estimate the potentialities of the ghost fishing to gillnet gears. Although the applications are not limited to geometries and internal forces, the paper describes how computer-aided simulations of fishing gear should be applied to investigations of the impact of ghost fishing caused by lost drift and bottom gillnets. The computational results showed that a driftnet with homogenous net panels was deformed slightly and bent only at the two ends of the net. Accumulation of periphyton on a bottom gillnet after 25 d of immersion caused it to settle to the sea bottom.
The Posterior Pedicle Inferior Turbinate Flap: A New Vascularized Flap for Skull Base Reconstruction
Authors: Fortes Felipe S. G. , Carrau Ricardo L. , Snyderman Carl H. , Prevedello Daniel , Vescan Allan , Mintz Arlan , Gardner Paul , Kassam Amin B.
Published: July 2007

Background: Expanded endonasal approaches (EEA) for the resection of lesions of the anterior and ventral skull base can create large defects with a significant risk of postoperative cerebrospinal fluid (CSF) leaks or exposure of the internal carotid artery. In these cases, a reconstruction using a vascularized flap facilitates rapid and complete healing of the defect. The Hadad‐Bassagasteguy flap (HBF), a posterior pedicle nasoseptal flap, is our preferred reconstructive option; however, a prior posterior septectomy or prior wide sphenoidotomies preclude its use. We have developed two additional pedicled flaps to reconstruct these selected patients: the transpterygoid temporoparietal fascia flap, which is suitable for large defects, and the posterior pedicle inferior turbinate flap (PPITF), the subject of this paper.

Methods: We developed a flap comprising the inferior turbinate mucoperiosteum pedicled on the inferior turbinate artery, a terminal branch of the posterior lateral nasal artery, which arises from the sphenopalatine artery. We retrospectively reviewed the clinical data of four patients who underwent a skull base reconstruction using a PPITF.

Results: Four patients underwent a reconstruction with the PPITF after undergoing an EEA that produced a skull base defect associated with a CSF fistula (n = 2), an exposed internal carotid artery (n = 1), or a basilar aneurysm clip (n = 1). All patients had undergone posterior septectomies as part of previous EEAs. All flaps healed uneventfully and covered the entire defect.

Conclusion: The PPITF is a viable reconstructive option for patients with skull base defects of a limited size defect and in whom the HBF is not available.
HIV‐Associated Facial Lipoatrophy: Establishment of a Validated Grading Scale
Authors: Funk Etai , Brissett Anthony E. , Friedman Craig D. , Bressler Fred J.
Published: July 2007

Objective: HIV‐associated lipodystrophy is considered a sequela of highly active antiretroviral treatment. We describe the characteristics, possible etiology, and pathophysiology of HIV‐associated lipodystrophy and facial lipoatrophy and establish a validated grading scale for HIV‐associated facial lipoatrophy using evidence‐based techniques.

Design/Methods: A grading scale was designed based on the severity of each patient's facial lipoatrophy. Preoperative photographs of HIV‐infected patients seeking treatment for facial lipoatrophy and control subjects were reviewed by physicians qualified in facial plastic surgery. With use of the devised grading scale, each patient was assigned a severity score. These scores were then compared for interrater variability, and the distribution of scores was analyzed.

Results: Preoperative photographs of 39 HIV‐infected individuals with facial lipoatrophy and 6 normal subjects were obtained and reviewed. All patients were males. A Cohen kappa of 0.73 was calculated, and there was a fairly equal distribution of all severity grades throughout the 39 patients.

Conclusion: HIV‐associated facial lipoatrophy is a major stigma for HIV patients that can have dramatic effects on their self‐esteem, social habits, and medication compliance. This current study introduces a validated evidence‐based grading scale that can be implemented to categorize disease severity. Using this scale will hopefully generate improved treatment plans directed to each patient, which should produce enhanced postoperative results.
The dynamic influence of genetic variation on the susceptibility of sheep to gastrointestinal nematode infection
Authors: Stear Michael J , Fitton Lesley , Innocent Giles T , Murphy Lisa , Rennie Kerry , Matthews Louise
Published: July 2007

The interaction between sheep and the nematodeTeladorsagia circumcinctais one of the best understood of all host–parasite interactions. Following infection, there is considerable variation among lambs in the number of nematode eggs produced, the number of early fourth-stage larvae and the number of adult worms in the mucosa. These traits have a high variance to mean ratio (i.e. they are overdispersed or aggregated among hosts), they are skewed and approximately negative binomially distributed. The sources of overdispersion are differences among lambs in the ingestion of infective larvae and the immune response. Both forces can produce aggregation but their relative importance is unknown. The key components of variation can be identified by variance analysis. The sum of the average effects of polymorphic genes is known as additive genetic variation and this increases essentially from zero at one month of age to quite high values at six months of age. The major mechanism underlying genetic variation appears to be the differences among individuals in immune responses. Two of the major sources of variation in immune responses are differences in antigen recognition and differences in the type of cytokines produced. Genes that influence both these sources of variation are associated with differences in resistance to nematode infection. Therefore, much of the heterogeneity among animals in parasite transmission appears to be due to genetic variation in immune responsiveness.
Discovery of an oncogenic activity in p27Kip1that causes stem cell expansion and a multiple tumor phenotype
Authors: Besson Arnaud , Hwang Harry C. , Cicero Samantha , Donovan Stacy L. , Gurian-West Mark , Johnson Dianna , Clurman Bruce E. , Dyer Michael A. , Roberts James M.
Published: July 2007

The cell cycle inhibitor p27Kip1also has cyclin–cyclin-dependent kinase (CDK)-independent functions. To investigate the significance of these functions in vivo, we generated a knock-in mouse in which four amino acid substitutions in thecdkn1bgene product prevent its interaction with cyclins and CDKs (p27CK−). In striking contrast to complete deletion of thecdkn1bgene, which causes spontaneous tumorigenesis only in the pituitary, the p27CK−protein dominantly caused hyperplastic lesions and tumors in multiple organs, including the lung, retina, pituitary, ovary, adrenals, spleen, and lymphomas. Moreover, the high incidence of spontaneous tumors in the lung and retina was associated with amplification of stem/progenitor cell populations. Therefore, independently of its role as a CDK inhibitor, p27Kip1promoted stem cell expansion and functioned as a dominant oncogene in vivo. Thus, the p27CK−mouse unveils a dual role for p27 during tumorigenesis: It is a tumor suppressor by virtue of its cyclin–CDK regulatory function, and also an oncogene through a cyclin–CDK-independent function. This may explain why thecdkn1bgene is rarely inactivated in human tumors, and the p27CK−mouse in which the tumor suppressor function is lost but the cyclin–CDK-independent—oncogenic—function is maintained may represent a more faithful model for the widespread role of p27 misregulation in human cancers than the p27 null.
Recovery from neuromuscular blockade: a survey of practice*
Authors: Grayling M. , Sweeney B. P.
Published: July 2007

At present in the UK there is no consensus regarding the parameters anaesthetists use to indicate adequacy of reversal from neuromuscular blockade. In an attempt to determine current practice, we carried out a survey covering 12 anaesthetic departments throughout the UK. Individuals were asked to give details regarding their usage of available monitors or, alternatively, to list those clinical parameters which they felt offered the best guidance as to the adequacy of recovery from neuromuscular blockade. There was no consensus among anaesthetists as to the most reliable clinical signs of recovery from neuromuscular blockade. There was an apparent lack of understanding of the limitations of some clinical signs used to determine recovery, as well as inappropriate application of others. In all departments where monitors (quantitative or qualitative) were available, there was limited knowledge regarding the current minimum recommended train‐of‐four ratio which should be observed prior to extubation. There is an apparent overall confusion among clinicians as to the best method to confirm recovery from neuromuscular blockade. This is probably due to the lack of a single reliable clinical test which can be applied in the immediate postoperative period. Insufficient reliance is placed upon the use of quantitative monitors. There is a lack of clarity in national anaesthetic guidelines with respect to monitoring of neuromuscular function. Current standards need to be re‐assessed in the light of recent improvements in nerve stimulators.
Intra‐operative awareness in children: the value of an interview adapted to their cognitive abilities
Authors: Lopez U. , Habre W. , Laurençon M. , Haller G. , Van der Linden M. , Iselin‐Chaves I. A.
Published: July 2007

Intra‐operative awareness in paediatric patients has been little studied for many years because of the difficulties in relying on children's testimony. Earlier questionnaires used to detect this complication were not adapted to children's language and memory capacities. By using a qualitative method, a semi‐structured in‐depth interview adapted to their cognitive abilities, we have now conducted a prospective evaluation of the incidence and risk factors for intra‐operative awareness in children undergoing general anaesthesia. Data were obtained from interviews with 410 children (aged 6–16 years) which were conducted within 36 h of general anaesthesia for elective or emergency surgery. One month after surgery, 293 of these patients were interviewed again. Three independent adjudicators classified each potential case of awareness. We considered awareness to include both the ‘confirmed awareness’ and the ‘possible awareness’ cases. The accuracy of the children's recall was calculated. The relationship between their awareness and the anaesthesia management was examined. There were five cases of confirmed awareness, and six cases of possible awareness. The incidence of confirmed awareness was 1.2%, but when the possible cases were also considered, the overall incidence of this complication was as high as 2.7% (95% confidence interval, 1.4–5.0%). The only predictive factor identified was the multiple manoeuvres with which the airways were secured (odds ratio, 8.4; 95% confidence interval, 2.4–29.07%). The present study confirms the existence of intra‐operative awareness in the paediatric population. The application of a semi‐structured in‐depth interview adapted to the cognitive capacities of the children appears to enhance the detection of awareness in this population.
Podocytes express ADAMTS13 in normal renal cortex and in patients with thrombotic thrombocytopenic purpura
Authors: Manea Minola , Kristoffersson AnnCharlotte , Schneppenheim Reinhard , Saleem Moin A. , Mathieson Peter W. , Mörgelin Matthias , Björk Peter , Holmberg Lars , Karpman Diana
Published: July 2007

Congenital thrombotic thrombocytopenic purpura (TTP) is associated with ADAMTS13 mutations. The major site of ADAMTS13 synthesis is the liver. Expression in other tissues, and in TTP, has not been shown. In this study, ADAMTS13 protein expression was investigated in normal kidney and in renal tissue from two TTP patients, with a compound heterozygous mutation (P353L and P457L) and a homozygous mutation (4143insA). Real‐time polymerase chain reaction demonstrated ADAMTS13 mRNA in normal kidney. ADAMTS13 was detected in the glomeruli and tubuli of normal and TTP kidney using anti‐ADAMTS13 antibodies. In the glomeruli, expression was localised to podocytes (as demonstrated by counterstaining with two podocyte markers) and endothelium. Similar distribution was detected in the TTP kidneys. Electron microscopy detected ADAMTS13 in podocytes, endothelium and glomerular basement membrane. Cultured human podocytes expressed ADAMTS13 mRNA and protein, and podocyte lysate exhibited von Willebrand factor‐cleaving activity. Mutation expression studies of the P353L and P457L mutations showed partially impaired secretion and lower activity of the secreted mutants. Impaired secretion has previously been shown for the 4143insA mutation. Podocyte‐derived ADAMTS13 may offer local protection in the high‐shear microcirculation of the glomerulus. The mutations in the two TTP patients studied enabled protein expression in the podocytes but affected protease secretion.
Prospective evaluation of the biological control of vine mealybug: refuge effects and climate
Authors: Gutierrez Andrew Paul , Daane Kent M. , Ponti Luigi , Walton Vaughn M. , Ellis C. Ken
Published: July 2007

Vine mealybug Planococcus ficus is an invasive pest of vineyards in many areas of the world. In California, USA, it infests all plant subunits and has a spatial refuge from natural enemies under the bark and on roots. A temporal refuge is created when ants tending the mealybug reduce the efficacy of natural enemies.

Biological control of vine mealybug is only partially successful and varies among California grape‐growing regions. To improve control and help determine appropriate natural enemies for importation, the effects of weather on mealybug regulation by two parasitoids, Anagyrus pseudococci and Leptomastidea abnormis, and a coccinellid predator, Cryptolaemus montrouzieri, were examined across the ecological regions of California.

Weather‐driven, physiologically based age–mass structured demographic models of the mealybug and its natural enemies were parameterized using laboratory data and field observations. Temperature was used to define the thermal limits and development rates of each species, and resource supply/demand ratios were used to scale daily per capita growth, fecundity and survivorship rates from maximal values at optimal conditions.

The population dynamics of the mealybug and its natural enemies were simulated at 108 locations in California over a 10‐year period using observed weather. The simulation data were mapped using a geographical information system (GIS) and analysed using linear multiple regression and marginal analysis.

The models predictions indicated that: (i) the parasitoid A. pseudococci has a larger impact on vine mealybug than either L. abnormis or C. montrouzieri; (ii) mealybug densities will be lowest in the hot desert regions of southern California and highest in the cooler areas of northern California; (iii) mealybug density increases with season length and the size of the combined spatial–temporal refuge; (iv) biological control of mealybug could be achieved by reducing the size of the spatial–temporal refuge.

Synthesis and applications. Models, no matter how detailed, will always be incomplete; despite this, the complexity of tri‐trophic systems can be modelled and the effects of biotic factors and of weather separated. The predictions of our model coincided well with field observations on vine mealybug, and clearly showed why the biological control will require additional species of natural enemies and/or why the size of the spatial and temporal refuges must be reduced.
Determinants of avian species richness at different spatial scales
Authors: Būhning‐Gaese Katrin
Published: July 2007

ABSTRACT. Studies of factors influencing avian biodiversity yield very different results depending on the spatial scale at which species richness is calculated. Ecological studies at small spatial scales (plot size 0.0025–0.4 km2) emphasize the importance of habitat diversity, whereas biogeographical studies at large spatial scales (quadrat size 400–50,000 km2) emphasize variables related to available energy such as temperature. In order to bridge the gap between those two approaches the bird atlas data set of Lake Constance was used to study factors determining avian species diversity at the intermediate spatial scales of landscapes (quadrat size 4–36 km2). At these spatial scales bird species richness was influenced by habitat diversity and not by variables related to available energy probably because, at the landscape scale, variation in available energy is small. Changing quadrat size between 4 and 36 km2, but keeping the geographical extension of the study constant resulted in profound changes in the degree to which the amount of different habitat types was correlated with species richness. This suggests that high species diversity is achieved by different management regimes depending on the spatial scale at which species richness is calculated. However, generally, avian species diversity seems to be determined by spatial heterogeneity at the corresponding spatial scale. Thus, protecting the diversity of landscapes and ecosystems appears to ensure also high levels of species diversity.
Distribution and frequencies of CDH23 mutations in Japanese patients with non‐syndromic hearing loss
Authors: Wagatsuma M , Kitoh R , Suzuki H , Fukuoka H , Takumi Y , Usami S
Published: July 2007

Mutations in the CDH23 gene are known to be responsible for both Usher syndrome type ID (USH1D) and non‐syndromic hearing loss (DFNB12), and the molecular confirmation of the CDH23 gene has become important in the diagnosis of these conditions. The present study was performed to find whether the CDH23 mutations are also responsible for non‐syndromic hearing loss in patients in the Japanese population. A total of 51 sequence variants were found in 64 Japanese probands with non‐syndromic sensorineural hearing impairment from autosomal recessive families. Among them, at least four missense mutations in six patients from five families were confirmed to be responsible for deafness by segregation study. All mutations detected were missense mutations, corroborating the previous reports regarding DFNB12. The present data confirmed that CDH23 mutations are frequently found and significantly responsible in Japanese. Interestingly, the CDH23 mutation spectrum in Japanese is very different from that found in Caucasians. This Japanese spectrum may be representative of those in Eastern Asian populations and its elucidation is expected to facilitate the molecular diagnosis of DFNB12 and USH1D.
Inhibition of polyamine biosynthesis by dicyclohexylamine in cultured cotyledons of Pinus radiata
Authors: Biondi Stefania , Torrigiani Patrizia , Sansovini Alba , Bagni Nello
Published: July 2007

Biondi, S., Torrigiani, P., Sansovini, A. and Bagni, N. 1988. Inhibition of polyamine biosynthesis by dicyclohexylamine in cultured cotyledons of Pinus radiata. ‐ Physiol. Plant. 72: 471–476.

The effect of 1 mAf dicyclohexylamine (DCHA) on the synthesis of spermidine and spermine was examined in excised cotyledons of radiata pine (Pinus radiata D. Don) cultured under shoot‐forming (with cytokinin) and non‐shoot‐forming (minus cytokinin) conditions by incubation with [14C]‐putrescine. In control cotyledons incorporation into spermidine showed a peak at day 2 in the presence and at day 5 in the absence of N6‐benzyldenine (BA). DCHA‐treated cotyledons gave the same labeling pattern, both in the presence and absence of benzyladenine, with a much smaller peak at day 2. The incorporation into spermidine and spermine was insignificant at day 5 and later. The total radioactivity in the trichloroacetic acid supernatant indicated that precursor uptake was strongly reduced by the drug. In addition, the percentage label found in the benzene phase and combined in the 3 polyamines was lower in DCHA‐treated cotyledons. Thus, treatment with DCHA not only inhibited the conversion from putrescine to spermidine and spermine, but also reduced its conversion to other benzene‐extractable compounds. S‐Adenosylmethionine decarboxylase (SAMDC, EC 4.1.1.50) activity, which furnishes the propylamine group to spermidine and spermine synthases (EC 2.5.1.16 and EC 2.5.1.‐), was not significantly affected by DCHA and appeared to be independent of the spermidine and spermine synthase reactions, suggesting that spermine synthesis decreased as a result of substrate depletion. The correlation between morphological development and polyamine biosynthesis is discussed.
Respiratory energy costs for the maintenance of biomass, for growth and for ion uptake in roots of Carex diandra and Carex acutiformis
Authors: van der Werf Adrie , Kooijman Annemieke , Welschen Rob , Lambers Hans
Published: July 2007

van der Werf, A., Kooijman, A., Welschen, R. and Lambers, H. 1988. Respiratory energy costs for the maintenance of biomass, for growth and for ion uptake in roots of Carex diandra and Carex acutiformis. ‐ Physiol. Plant. 72: 483–491.

The respiratory characteristics of the roots of Carex diandra Schrank and Carex acutiformis Ehrh. were investigated. The aims were, firstly to determine the respiratory energy costs for the maintenance of root biomass, for root growth and for ion uptake, and secondly to explain the higher rate of root respiration and ATP production in C. diandra.

The three respiratory energy components were derived from a multiple regression analysis, using the relative growth rate and the net rate of nitrate uptake as independent variables and the rate of ATP production as a dependent variable. Although the rate of root respiration and ATP production was significantly higher in C. diandra than in C. acutiformis, the two species showed no significant difference in their rate of ATP production for the maintenance of biomass, in the respiratory energy coefficient for growth (the amount of ATP production per unit of biomass produced) and the respiratory energy coefficient for ion uptake (amount of ATP production per unit of ions absorbed). It is concluded that the higher rate of root respiration of C. diandra is caused by a higher rate of nitrate uptake. At relatively high rates of growth and nitrate uptake, the contribution of the rate of ATP production for ion uptake to the total rate of ATP production amounted to 38 and 25% for C. diandra and C. acutiformis, respectively. At this growth rate, the respiratory energy production for growth contributed 37 and 50%, respectively, to the total rate of ATP production. The relative contribution of the rate of ATP production for the maintenance of biomass increased from 25 to 70% with increasing plant age for both species. The results suggest that ion uptake is one of the major sinks for respiratory energy in roots.

These experimentally derived values for the rate of ATP production for the maintenance of biomass, the respiratory energy coefficient for growth and the respiratory energy coefficient for ion uptake are discussed in relation to other experimentally and theoretically derived values.
Discovering Price in All the Wrong Places: The Work of Commodity Definition and Price under Neoliberal Environmental Policy
Authors: Robertson Morgan
Published: July 2007

Abstract:  Price plays a unique role in neoliberal economic theory, quantifying value and providing markets with the information needed to produce equilibrium conditions and optimal social welfare. While the role of price is clear, the mechanisms by which prices are discovered, and by which the commodities they value are defined, are left obscure in neoliberal theory. Automatic price discovery, and self‐evident commodity identities, are assumed. Observation of newly created markets in ecosystem services suggests that this is a moment of significant tension within neoliberal practice, as potential market participants seek guidance from the state on appropriate commodity measures and pricing practices. Bureaucrats and economists, following the neoliberal preference for governance over government, turn the task back onto civil society. The invocation of abstract rules, instead of the formulation of practical guidance, by policymakers means that the neoliberal marketization of non‐market public goods is a contingent and sometimes rudderless task for those who must make markets work on the ground. This presents many opportunities for constructive engagement on the part of geographers and other critics of neoliberal strategy.