bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dry nitrogen deposition estimates over a forest experiencing free air CO2 enrichment
Authors: SPARKS JED P. , WALKER JOHN , TURNIPSEED ANDREW , GUENTHER ALEX 
Published: March 2008

AbstractThe quantification of atmospheric additions of nitrogen (N) to an ecosystem is often desirable, but difficult for many locations including many ecological manipulation experiments. Ideal methodologies for the complete and chemically speciated quantification of dry N deposition (e.g. tunable diode laser absorption spectrometer, thermal‐dissociation laser‐induced fluorescence) are expensive, technologically challenging to maintain, and rarely colocated with important global change manipulation experiments. Here we present an alternative method for obtaining an approximation of total N deposition using short‐term eddy flux and concentration measurements, annual regional concentration estimates, and modeling for the Duke Experimental Forest. The motivation for generating estimates for this location was to inform the long‐term elevated CO2 experiment conducted at Duke Forest. We estimated the total annual atmospheric N deposition to the forest to be 13.7 kg N ha−1. Of this total, ∼58% was in dry‐deposited forms. Surprisingly, and contrary to some previous predictions, nitric acid (HNO3) was not the dominant portion of the total dry‐deposited N, implying strongly that other forms of gaseous N like organic peroxy and alkyl nitrate compounds are a significant portion of the total flux. Furthermore, this study sheds light on the completeness of the estimates derived from Clean Air Status and Trends Network (CASTNet) and other dry deposition networks. CASTNet does not measure organic forms of dry deposition. In fact, CASTNet only quantifies HNO3 in the gas phase and may significantly underestimate total N deposition in many environments.
Spring warming and carbon dioxide exchange over low Arctic tundra in central Canada
Authors: LAFLEUR PETER M. , HUMPHREYS ELYN R. 
Published: March 2008

AbstractTundra‐atmosphere exchanges of carbon dioxide (CO2) and water vapour were measured near Daring Lake, Northwest Territories in the Canadian Low Arctic for 3 years, 2004–2006. The measurement period spanned late‐winter until the end of the growing period. Mean temperatures during the measurement period varied from about 2 °C less than historical average in 2004 and 2005 to 2 °C greater in 2006. Much of the added warmth in 2006 occurred at the beginning of the study, when snow melt occurred 3 weeks earlier than in the other years. Total precipitation in 2006 (163 mm) was more than double that of the driest year, 2004 (71 mm). The tundra was a net sink for CO2 carbon in all years. Mid‐summer net ecosystem exchange of CO2 (NEE) achieved maximum values of −1.3 g C m−2 day−1 (2004) to −1.8 g C m−2 day−1 (2006). Accumulated NEE values over the 109‐day period were −32,−51 and −61 g C m−2 in 2004, 2005 and 2006, respectively. The larger CO2 uptake in 2006 was attributed to the early spring coupled with warmer air and soil conditions. In 2004, CO2 uptake was limited by the shorter growing season and mid‐summer dryness, which likely reduced ecosystem productivity. Seasonal total evapotranspiration (ET) ranged from 130 mm (2004) to 181 mm (2006) and varied in accordance with the precipitation received and with the timing of snow melt. Maximum daily ET rates ranged from 2.3 to 2.7 mm day−1, occurring in mid July. Ecosystem water use efficiency (WUEeco) varied slightly between years, ranging from 2.2 in the driest year to 2.5 in the year with intermediate rainfall amounts. In the wettest year, increased soil evaporation may have contributed to a lower WUEeco (2.3). We speculate that most, if not all, of the modest growing season CO2 sink measured at this site could be lost due to fall and winter respiration leading to the tundra being a net CO2 source or CO2 neutral on an annual basis. However, this hypothesis is untested as yet.
Methane bubbles in surface peat cores: in situ measurements
Authors: LAING CHRISTOPHER GRAHAM , SHREEVE TIMOTHY GEORGE , PEARCE DEBORAH MARIE ELIZABETH 
Published: March 2008

AbstractThe quantification of greenhouse gas sources and sinks is important to understanding the impact of climate change. Methane (CH4) is a potent greenhouse gas, which, on a global scale, is released largely as a product of anaerobic microbial decomposition and predominantly from wetlands. A zone of intense CH4 production just below the water table is thought to contribute significantly to the overall flux from peat bogs. We describe the use of membrane inlet quadrupole mass spectrometry (QMS) to confirm the existence of bubbles, their gaseous concentrations and their localization at a fine spatial resolution within intact peat cores. We use the distribution of the noble gas argon (Ar) and the distinct QMS responses to dissolved and gaseous (bubble) phases to identify trapped bubbles with a resolution of 0.6 mm. Bubbles with CH4 concentrations of up to 20 kPa were widely distributed in the upper 300 mm of the cores with ∼11% of all profiles comprising bubbles. The dissolved concentrations responsible for the bubbles were on average 83±80 μm, indicating lower concentrations relative to other QMS studies. We suggest that if the distinction between dissolved and gaseous phases is not made in studies of CH4 within peat profiles then the prominence of bubbles is likely to result in overestimates of dissolved CH4 concentrations. Fluxes of CH4 from peat as a result of drawdown or other perturbation are likely to be large, rapid and short lived because of bubble burst, and also larger than from peat without bubbles. We suggest that the dynamics of fluxes need to be modelled taking into account both gaseous and dissolved phases. Estimates of potential fluxes that assume CH4 is dissolved are likely to overestimate fluxes if the gaseous phase has not been taken into account.
Soft systems and systems engineering: on the use of conceptual models in information system development
Authors: Doyle K. G. , Wood J. R. G. , Wood‐Harper A. T. 
Published: March 2008

Abstract. Many recent studies have shown that computer‐based systems continue to ‘fail’ at a number of different levels (Romtec, 1988; KPMG, 1990) and it is increasingly apparent (Maclaren et al., 1991) that the most serious failures of information technology (IT) lie in the continuing inability to address those concerns which are central to the successful achievement of individual, organizational and social goals. It is the contention of this paper that this failing is precisely because these are the areas which are ignored or inadequately treated by conventional system development methods.There is, of course, a vast body of literature concerned with the understanding of complex human activity systems. This literature often reflects a mass of contradictions at the epistemological and the ontological level about the behaviour of such systems and has also spawned numerous methods (and methodologies) which seek to guide the individual in making successful interventions into organizational situations (Rosenhead, 1989).Despite this multiplicity of viewpoints many writers have posited a dichotomy between so‐called 'soft and ‘hard’ approaches to problem situations and use this dichotomy to inform the choice of an appropriate problem‐solving methodology (Checkland, 1985). In this paper we characterize these two approaches as being concerned with either the purpose(s) of the human activity system (i.e. ‘doing the right thing’) or with the design of the efficient means of achieving such purpose(s) (i.e. ‘doing the thing right’).It is our belief that much of the literature and work in either area has not concerned itself with the issues of the other. Writers on ‘hard’ engineering methods often assume the question of purpose to be either straightforward (e.g. given in the project brief) or, paradoxically, too difficult (e.g. it is not our concern as mere systems analysts). Writers on ‘soft’ methods on the other hand rarely have anything to say about the design and implementation of well‐engineered computer‐based systems, giving the impression that this is a somewhat mundane activity better left to technical experts.This paper, therefore, attempts to set out a rationale for the bringing together of principles from both ‘hard’ engineering and ‘soft’ inquiry methods without doing epistemological damage to either. To illustrate our argument we concentrate on JSD (Jackson system development) as an example of system engineering (Cameron, 1983) and SSM (soft systems methodology) as an example of system inquiry (Checkland, 1981; Checkland & Scholes, 1990). Our general thesis, however, does not depend upon either of these two approaches per se but applies to the overall issue of bringing together insights from two apparently opposed epistemological positions in an effort better to harness the power of IT in pursuit of purposeful human activity.
The impact of EDI implementation commitment and implementation success on competitive advantage and firm performance
Authors: Rao H. R. , Pegels C. C. , Salam A. F. , Hwang K. T. , Seth V. 
Published: March 2008

Abstract. Electronic Data Interchange Systems (EDI) are increasingly being used by business firms to improve operations and customer service. One of the major motivations for business organizations using EDI is to gain a strategic advantage in the marketplace. Although EDI has been implemented by many organizations, unfortunately not all have gained the same level of expected advantage or envisioned benefits.In this study we focus on the impact of EDI implementation commitment and implementation success on competitive advantage and firm performance. We study two categories of companies: companies that initiate the development of EDI and are known as hub companies and those that are their non‐hub counterparts. Findings indicate that non‐hub firms may not reap the same level of expected benefits resulting from EDI technology adoption and implementation as hub firms.
Different clinical outcomes following root fractures of adjacent incisors: a case report
Authors: Schmitz M. S. , Montagner F. , Montagner H. , Escobar C. A. B. , Dos Santos R. A. , Gomes B. P. F. A. 
Published: March 2008

AbstractAim  To report different patterns of root fracture healing in adjacent maxillary central incisors with distinct post‐treatment outcomes.Summary  To describe the case of a 12‐year‐old girl who presented with an avulsed coronal fragment of tooth 11 and root fractures in the middle thirds of teeth 11 and 21. Four months after initial treatment, she was referred for specialized endodontic care. Tooth 11 presented no clinical or radiographic signs of pulp breakdown. However a sinus tract was found related to the middle root third of tooth 21, indicating pulp necrosis in the coronal fragment. The coronal fragment was root filled and periapical surgery was performed to remove the apical fragment. Twelve months after the clinical procedures and 16 months after trauma, hard tissue healing was evident in tooth 11 region. Bone healing was also satisfactory in the periapical region of tooth 21.Key learning points

Even adjacent teeth may display different reaction patterns after trauma.
The prognosis of root fractures is variable and different clinical approach may be required to preserve teeth with fractured roots.
Catheter‐related bloodstream infections in intensive care units: a systematic review with meta‐analysis
Authors: Ramritu Prabha , Halton Kate , Cook David , Whitby Michael , Graves Nicholas 
Published: March 2008

AbstractTitle.  Catheter‐related bloodstream infections in intensive care units: a systematic review with meta‐analysis Aim.  This paper is a report of a systematic review and meta‐analysis of strategies, other than antimicrobial coated catheters, hypothesized to reduce risk of catheter‐related bloodstream infections and catheter colonization in the intensive care unit setting.Background.  Catheter‐related bloodstream infections occur at a rate of 5 per 1000 catheter days in the intensive care unit setting and cause substantial mortality and excess cost. Reducing risk of catheter‐related bloodstream infections among intensive care unit patients will save costs, reduce length of stay, and improve outcomes.Methods.  A systematic review of studies published between January 1985 and February 2007 was carried out using the keywords ‘catheterization – central venous’ with combinations of infection*, prevention* and bloodstream*. All included studies were screened by two reviewers, a validated data extraction instrument was used and data collection was completed by two blinded independent reviewers. Risk ratios for catheter‐related bloodstream infections and catheter colonization were estimated with 95% confidence intervals for each study. Results from studies of similar interventions were pooled using meta‐analyses.Results.  Twenty‐three studies were included in the review. The strategies that reduced catheter colonization included insertion of central venous catheters in the subclavian vein rather than other sites, use of alternate skin disinfection solutions before catheter insertion and use of Vitacuff in combination with polymyxin, neomycin and bacitracin ointment. Strategies to reduce catheter‐related bloodstream infection included staff education multifaceted infection control programmes and performance feedback.Conclusion.  A range of interventions may reduce risks of catheter‐related bloodstream infection, in addition to antimicrobial catheters.
Burnout and physical and mental health among Swedish healthcare workers
Authors: Peterson Ulla , Demerouti Evangelia , Bergström Gunnar , Samuelsson Mats , Åsberg Marie , Nygren Åke 
Published: March 2008

AbstractTitle.  Burnout and physical and mental health among Swedish healthcare workers Aim.  This paper is a report of a study to investigate how burnout relates to self‐reported physical and mental health, sleep disturbance, memory and lifestyle factors.Background.  Previous research on the possible relationship between lifestyle factors and burnout has yielded somewhat inconsistent results. Most of the previous research on possible health implications of burnout has focused on its negative impact on mental health. Exhaustion appears to be the most obvious manifestation of burnout, which also correlates positively with workload and with other stress‐related outcomes.Method.  A cross‐sectional study was conducted, using questionnaires sent to all employees in a Swedish County Council (N = 6118) in 2002. The overall response rate was 65% (n = 3719). A linear discriminant analysis was used to look for different patterns of health indicators and lifestyle factors in four burnout groups (non‐burnout, disengaged, exhausted and burnout).Results.  Self‐reported depression, anxiety, sleep disturbance, memory impairment and neck‐ and back pain most clearly discriminated burnout and exhausted groups from disengaged and non‐burnout groups. Self‐reported physical exercise and alcohol consumption played a minor role in discriminating between burnout and non‐burnout groups, while physical exercise discriminated the exhausted from the disengaged group.Conclusion.  Employees with burnout had most symptoms, compared with those who experienced only exhaustion, disengagement from work or no burnout, and the result underlines the importance of actions taken to prevent and combat burnout.
Stability of exotic annual grasses following restoration efforts in southern California coastal sage scrub
Authors: Cox Robert D. , Allen Edith B. 
Published: March 2008

Summary

Restoration of semi‐arid shrub ecosystems often requires control of invasive grasses but the effects of these grass‐control treatments on native and exotic forbs have not been investigated adequately to assess long‐term stability. In southern California, coastal sage scrub (CSS) vegetation is one semi‐arid shrub community that has been invaded extensively by both exotic grasses and exotic forbs and is a target for restoration.
We studied the effects of grass‐specific herbicide, thatch removal plus herbicide and mowing on native and exotic species in a heavily invaded CSS community. We followed this grass‐control experiment for 6 years to assess the stability of such treatments. We also added a soil disturbance experiment to investigate the potential influence of thatch removal and soil disturbance on exotic and native grasses and forbs.
In the grass‐control experiment, treatments reduced exotic grass cover to differing degrees. Three years of mowing resulted in lower exotic grass cover, but only for 2 years. Both herbicide and herbicide plus thatch removal reduced exotic grasses more than mowing, and effects persisted for longer. However, reducing exotic grass cover increased seeded species only during the year of seeding. In addition, plots where exotic grasses were controlled by herbicides also experienced increases in exotic forb cover.
In the soil‐disturbance experiment, treatments did not increase cover of native species, although plots in which soil was disturbed did have less exotic grass cover. In both experiments, plots observed in years with different rainfall experienced widely varied plant cover, emphasizing the influence that precipitation exerts in these systems.
Synthesis and applications. In restoration of semi‐arid shrub ecosystems, grass control can reduce exotic grasses over the short‐term. However, recovery of grasses in the longer term indicates that restoration does not form a new stable state. Restoration and management of semi‐arid shrublands may therefore require continual grass control. Exotic forbs should also be considered for control, as they may increase when exotic grasses are removed. Yearly variations in precipitation confound determination of successful restoration efforts, and require long‐term observations to detect the response of native species to treatments.
The role of research for integrated management of invasive species, invaded landscapes and communities
Authors: Buckley Yvonne M. 
Published: March 2008

Summary

Invaded landscapes and ecosystems are composed of multiple interacting networks and feed‐back loops, sometimes leading to unexpected effects of management actions. In order to plan management for invaded systems we need to explicitly consider management goals before putting actions in place. Actions taken must be justified in terms of their amelioration of impacts of invaders, contribution to the management goals and the costs incurred.
This Special Profile brings together papers on the management of invasive plants, transgenes, animals and diseases, leading to conclusions with clear policy and management relevance and contributing to some of the hottest current topics in invasion ecology: unexpected impacts of invaders, restoration of invasion resistance, distribution mapping, spatial epidemiology, escape of transgenes, community interactions and complex effects of management.
As papers in this Special Profile demonstrate, management for amelioration of the impacts of invasive species will include a wide range of manipulations, not just of the invader itself but of both abiotic and biotic components of the system. In fact, several papers in this Special Profile show that indirect management of the community may be more effective than removal of the invader alone.
As little information is generally available at the beginning of a management programme, an adaptive approach should be taken and the management objectives/goals revised throughout the management process. New methods are emerging for adaptive management; an example is presented in this Special Profile where a Bayesian model used for assessing eradication goals can be updated throughout the management process leading to refinement of management.
Synthesis and applications. Applied research should be directed at providing decision support for managers throughout the management process and can be used to provide predictive tools for risk assessment of new invaders. The science of invasion ecology has much to contribute to the new challenge of natural or enhanced movement of organisms in relation to climate change. Methods and information from invasion ecology can be used to assess management goals, management actions and the risks of potential translocations before they are put in place.
Cooperation in the care for patients with home enteral tube feeding throughout the care trajectory: nurses’ perspectives
Authors: Bjuresäter Kaisa , Larsson Maria , Nordström Gun , Athlin Elsy 
Published: March 2008

Aim.  The aim of this study was to explore how the planning, daily care and follow‐up procedures work in the care trajectory for patients treated with home enteral tube feeding, from the perspective of hospital and community care nurses.Background.  Discharge planning for patients in need of home enteral tube feeding is a complex process. Several studies have described routines for discharge and care of patients with home enteral tube feeding in the care trajectory, but few studies have investigated how this really works.Method.  A qualitative method with a phenomenographic approach was used. Interviews, with open‐ended questions, with ten nurses from both hospitals and communities were performed.Findings.  One main category, ‘cooperation’, emerged, which describes an hierarchical relationship to three description categories: ‘nurses’ knowledge’, ‘nurses’ view of responsibility’ and ‘nurses’ professional awareness and commitment’. Each of these contained two sub‐categories showing a positive and a negative pole.Conclusions.  Cooperation in the care of patients with home enteral tube feeding throughout the care trajectory was influenced by the nurses’ knowledge about enteral tube feeding, the discharge‐planning process, and whether their responsibility was clearly distributed. Whether nurses had a patient‐ or task‐oriented attitude was also important. Inefficient cooperation was considered having negative effects on the quality of care regarding home enteral tube feeding.Relevance to clinical practice.  This study has stressed the need for improving cooperation and communication between nurses at hospitals and in communities, as well as for increasing nurses’ level of knowledge, to make home enteral tube feeding work in a safe way. It also has illuminated the urgent need to clarify responsibility distribution at the workplace, which is a question for nurse managers. Discussions should be undertaken among nurses about guidelines for tube feeding care and discharge process, as this is the responsibility of all professional nurses.