bluuebunny/crossref_metadata_2025_split huggingface dataset:
What accounts for hospital readmission?
Authors: Wong Frances KY , Chan Moon Fai , Chow Susan , Chang Katherine , Chung Loretta , Lee Wai‐man , Lee Rance 
Published: October 2010

Aims. This study was launched to address the knowledge gap regarding factors leading to readmission to hospital.Background. Repeated hospital admission is an issue of concern for health care service providers. Research findings reveal that multiple factors can contribute to the phenomenon, but no study has examined the direct and indirect effects of these variables on hospital readmission.Design. A survey conducted during the period from 2003–2005 in three hospitals in Hong Kong.Methods. Patients who were readmitted to the same hospital within 28 days during the study periods were included. Data were collected using structured interviews. A structural equation model was employed to examine what factors will contribute to hospital readmission.Results. The final model showed that subjective health outcome was the only significant variable that had a direct effect on readmission, and it had indirect effects on readmission mediating through the variables of age, income and satisfaction with care.Conclusions. A literature review reveals that none of the studies has recognised patients’ subjective appraisal of their health condition as a significant variable to predict hospital readmission. Results did not find an association between evaluated and perceived need. In other words, patients who felt a higher need for hospital care were not necessarily sicker. It is possible that if patients can be empowered to manage their own health condition and make a fair appraisal of their well‐being, unnecessary use of hospital services can be reduced.Relevance to clinical practice. This study provides evidence to support the notion that an effective transitional care programme needs to incorporate patients’ own subjective assessment of health in the intervention and measurement of the outcome. We cannot solely use providers’ judgment to measure health outcomes, for patients are active agents in seeking health care, and the use of services is to an extent self‐selective.
Literature review: do rapid response systems reduce the incidence of major adverse events in the deteriorating ward patient?
Authors: Massey Debbie , Aitken Leanne M , Chaboyer Wendy 
Published: October 2010

Aims. To conduct a literature review that explores the impact of rapid response systems on reducing major adverse events experienced by deteriorating ward patients.Background. Patients located on hospitals wards are frequently older, have multiple co‐morbidities and are often at risk of life‐threatening clinical deterioration. Rapid response systems have been developed and implemented to provide appropriate and timely intervention to these patients.Design. A comprehensive review of the literature.Methods. This review used the rapid response systems framework recently developed by experts in the area. Medline, CINAHL, Embase and Cochrane databases were searched from January 1995–June 2009. Sixteen papers were selected that most clearly reflected the research aim. Each paper was critically appraised and systematically assessed. Major themes and findings were identified for each of the studies.Results. The effectiveness of rapid response systems in reducing major adverse events in deteriorating ward patients remains inconclusive. Six studies demonstrated that the introduction of a rapid response systems positively impacted on patient outcomes, but three studies demonstrated no positive impact on patient outcomes. Nursing staff appear reluctant to use rapid response systems; the rationale for this is unclear. However, the continued underuse and inactivation may be one reason why research findings evaluating rapid response systems have been inconclusive.Conclusions. The paper illustrates two important gaps in the literature. First, ‘ramp‐up’ systems have not been subjected to formal evaluation. Second, rapid response systems are under‐activated and underused by nursing staff. There is an urgent need to explore the reasons for this and to identify interventions to improve the activation of these systems in an effort to promote safe and effective care to the deteriorating ward patient.Relevance to clinical practice. Rapid response systems are multidimensional models. They are relatively new innovations that have important implications for clinical research and implementation policy. This review contributes to the emerging debate on rapid response systems.
Don’t ask don’t tell: substance abuse and addiction among nurses
Authors: Monroe Todd , Kenaga Heidi 
Published: October 2010

Aim.  The purpose of this manuscript is to illustrate the challenges faced by nurses who abuse substances and to promote international dialogue about what practitioners, administrators, health care providers and students can do when they suspect someone in the profession is abusing substances, or they may themselves be suffering from addiction.Background.  Addiction among nurses has been recognised by professionals in the field for over 100 years, and current estimates place rates of substance misuse, abuse and addiction rates as high as 20% among practicing nurses. Unfortunately, fear of punishment and discipline may keep nurses or students from asking for help for themselves or from reporting a colleague or friend who is in need of help.Design.  Discursive paper.Method.  This paper synthesises the results of three previous papers conducted on substance abuse policies in the nursing profession. In the first paper, the authors reviewed the history of addiction in nursing and compared disciplinary and alternative‐to‐discipline policies. The second focused on the development of an alternative‐to‐dismissal policy for substance abuse in a school of nursing and using telephone and email interviews, and the final paper reported findings of what types of polices seem to be working to retain and rehabilitate nurses who suffer from addiction in the USA. Lastly, this paper introduces international policy for nurses with addictions.Conclusions.  Poor or ineffective policies that mandate punitive action endanger the public by making it difficult for impaired students or professionals to ask for help. Providing early intervention and assistance is essential in helping colleagues and students recover from an addictive disorder and providing a non‐punitive atmosphere of support may well be a life‐saving first step for nurses and those in their care. Many territories and countries throughout the world now offer confidential, non‐punitive, assistance for nurses suffering from addictions.Relevance to clinical practice.  Recognition of a colleague’s need of treatment is the important first step in the rehabilitation process. Early intervention and assistance are essential for helping colleagues and students to recover from an addictive disorder and providing a confidential, non‐punitive atmosphere of support may well be a life‐saving first step for nurses and those in their care.
Stress tolerance and biotic interactions determine plant zonation patterns in estuarine marshes during seedling emergence and early establishment
Authors: Engels J. Gesina , Rink Florian , Jensen Kai 
Published: October 2010

Summary 1. Transplant experiments with adult plants showed that marsh plant zonation along estuarine salinity gradients develops according to species tolerances of abiotic factors and biotic interactions. Thus, glycophytes are restricted from salt marshes by abiotic stress, whereas halophytes are excluded from freshwater marshes by competition. We hypothesized that adult plant zonations along estuarine stress gradients are predefined by processes affecting plants during their seedling phase. In an experimental glasshouse study, we tested how a mixed community of glycophytes and halophytes developed during the first months of early establishment affected by different flooding and salinity regimes. 2. We set up two factorial mesocosm experiments that tested the effects of three tidal regimes (daily tide, spring tide, no tide) and three salinity levels (fresh, brackish, salt) on the emergence and early establishment of glycophyte and halophyte seedlings. In the Emergence Experiment seedlings were identified and removed once per week. In the Establishment Experiment species cover was estimated every 2 weeks, and after 15 weeks final above‐ground biomass of each species was determined. 3. Both glycophytes and halophytes showed highest seedling emergence under freshwater conditions. Emergence of halophytes was less impaired by increased salinities than that of glycophytes. Emergence and establishment of glycophytes were extremely reduced under brackish and salt conditions, whereas under freshwater conditions, glycophytes showed a consistent increase in cover over time. Cover of halophytes showed a similar increase in brackish and salt treatments; however, in freshwater treatments it significantly decreased after week 9. While daily tides predominantly decreased seedling emergence and establishment, spring tides had no significant effects on seedlings in freshwater and negative effects in saltwater treatments. 4. Synthesis. The ability of a species to germinate and emerge under conditions representing a particular position along an environmental gradient is necessary but not solely responsible for determining plant zonation patterns along estuarine marsh gradients. Our results show that competitive exclusion of halophytes by glycophytes as an important driver of marsh plant zonations along estuarine salinity gradients takes effect already during the early seedling establishment phase of the co‐occurring plants.
Leftovers in seed dispersal: ecological implications of partial seed consumption for oak regeneration
Authors: Perea Ramón , San Miguel Alfonso , Gil Luis 
Published: October 2010

Summary1.Successful seed dispersal by animals is assumed to occur when undamaged seeds arrive at a favourable microsite. Most seed removal and dispersal studies consider only two possible seed fates, predation or escape intact. Whether partial consumption of seeds has ecological implications for natural regeneration is unclear. We studied partial consumption of seeds in a rodent‐dispersed oak species.2.Fifteen percent of dispersed acorns were found partially eaten in a field experiment. Most damage affected only the basal portion of the seeds, resulting in no embryo damage. Partially eaten acorns had no differences in dispersal distance compared to intact acorns but were recovered at farther distances than completely consumed acorns.3.Partially eaten acorns were found under shrub cover unlike intact acorns that were mostly dispersed to open microhabitats.4.Partially eaten acorns were not found buried proportionally more often than intact acorns, leading to desiccation and exposure to biotic agents (predators, bacteria and fungi). However, partial consumption caused more rapid germination, which enables the acorns to tolerate the negative effects of exposure.5.Re‐caching and shrub cover as microhabitat of destination promote partial seed consumption. Larger acorns escaped predation more often and had higher uneaten cotyledon mass. Satiation at seed level is the most plausible explanation for partial consumption.6.Partial consumption caused no differences in root biomass when acorns experienced only small cotyledon loss. However, root biomass was lower when acorns experienced heavy loss of tissue but, surprisingly, they produced longer roots, which allow the seeds to gain access sooner to deeper resources.7.Synthesis.Partial consumption of acorns is an important event in the oak regeneration process, both quantitatively and qualitatively. Most acorns were damaged non‐lethally, without decreasing both dispersal distances and the probability of successful establishment. Faster germination and production of longer roots allow partially eaten seeds to tolerate better the exposure disadvantages caused by the removal of the pericarp and the non‐buried deposition. Consequently, partially consumed seeds can contribute significantly to natural regeneration and must be considered in future seed dispersal studies.
Dominant frequency of loud mew calls of felids (Mammalia: Carnivora) decreases during ontogenetic growth
Authors: PETERS Gustav 
Published: October 2010

ABSTRACT

A negative correlation between body weight and frequency characteristics of a species' vocalizations exists in mammals, due to the acoustics of vocal sound production (‘source‐filter theory’; source = larynx; filter = supralaryngeal vocal tract) and the strong positive correlation between body weight and vocal tract length.
A negative correlation is hypothesized to exist between increasing body weight and frequency characteristics of calls during ontogeny as well.
This hypothesis is tested for mean dominant frequency (maximum spectral energy peak) of intense mew calls in juveniles of five species of the Felidae: lion Panthera leo, jaguar Panthera onca, leopard Panthera pardus, tiger Panthera tigris and puma Puma concolor.
In the five felid species in which the hyoid is incompletely ossified (genera Panthera and Uncia), the larynx undergoes a considerable ontogenetic descent, resulting in a proportionally longer vocal tract in adult individuals than in all other species of the family, which have a fully ossified hyoid without a descent.
In all five species studied here, mean dominant frequency decreases as body weight increases during growth. In the four Panthera species (with laryngeal descent) dominant frequency is determined by the vocal tract (the filter), and dominant frequency is largely similar at similar weights, indicating a similar correlation between the ontogenetic increase in body weight (and vocal tract length) and the decrease in mean dominant frequency. In the puma (without laryngeal descent) dominant frequency is determined by the larynx (the source), it is considerably higher than in the Panthera species, and the course of its ontogenetic decrease differs considerably from that in Panthera.
The data do not support a uniform scaling relationship between body weight and mean dominant frequency of intense mew calls in the Felidae during ontogenetic growth.
Landscape genetics of the key African acacia species Senegalia mellifera (Vahl)– the importance of the Kenyan Rift Valley
Authors: RUIZ GUAJARDO J. C. , SCHNABEL A. , ENNOS R. , PREUSS S. , OTERO‐ARNAIZ A. , STONE G. 
Published: October 2010

AbstractAcacias across Africa have enormous ecological and economic importance, yet their population genetics are poorly studied. We used seven microsatellite loci to investigate spatial genetic structure and to identify potential ecological and geographic barriers to dispersal in the widespread acacia, Senegalia (Acacia) mellifera. We quantified variation among 791 individuals from 28 sampling locations, examining patterns at two spatial scales: (i) across Kenya including the Rift Valley, and (ii) for a local subset of 11 neighbouring locations on Mpala Ranch in the Laikipia plateau. Our analyses recognize that siblings can often be included in samples used to measure population genetic structure, violating fundamental assumptions made by these analyses. To address this potential problem, we maximized genetic independence of samples by creating a sibship‐controlled data set that included only one member of each sibship and compared the results obtained with the full data set. Patterns of genetic structure and barriers to gene flow were essentially similar when the two data sets were analysed. Five well‐defined geographic regions were identified across Kenya within which gene flow was localized, with the two strongest barriers to dispersal splitting the Laikipia Plateau of central Kenya from the Western and Eastern Rift Valley. At a smaller scale, in the absence of geographic features, regional habitat gradients appear to restrict gene flow significantly. We discuss the implications of our results for the management of this highly exploited species.
Diversification of plant species in a subtropical region of eastern South American highlands: a phylogeographic perspective on nativePetunia(Solanaceae)
Authors: LORENZ‐LEMKE ALINE P. , TOGNI PAKISA D. , MÄDER GERALDO , KRIEDT RAQUEL A. , STEHMANN JOÃO R. , SALZANO FRANCISCO M. , BONATTO SANDRO L. , FREITAS LORETA B. 
Published: October 2010

AbstractIn the Southern and Southeastern Brazilian highlands, a clade of seven species ofPetuniathat are endemic to the region (P. altiplana,P. bonjardinensis,P. guarapuavensis,P. mantiqueirensis,P. reitzii, P. saxicolaandP. scheideana) exists in association with grassland formations. These formations are isolated in high‐altitude regions, being surrounded by forested areas, and experienced contraction–expansion cycles associated with the glacial cycles of the Pleistocene. To understand the evolutionary history of this group, the divergence of which is probably linked to these past shifts in habitat, we analysed the sequences of the plastidial intergenic spacerstrnH‐psbAandtrnS‐trnGfrom populations throughout the known distributions of all seven species. The common ancestor of this highland clade started to differentiate ∼0.9 million years (Myr) ago, which corresponds to a high diversification rate of 2.06 species per Myr in the intervening period. The high level of haplotype sharing among several species in the clade and the absence of reciprocal monophyly suggest the persistence of ancestral polymorphisms during speciation events and/or past hybridization, because no hybrid was found. Four of the five species displayed very low genetic diversity and possessed either one or two haplotypes, which is consistent with long‐term isolation in restricted areas. The three more diverse species displayed significant population structure, andP. altiplanashowed a clear signs of population growth during the last glacial period. These results suggest that diversification occurred as a result of expansion of the ancestral species of the clade during glacial periods followed by fragmentation and isolation during retraction in interglacial periods.
Hydrogen peroxide inactivates the Escherichia coli Isc iron‐sulphur assembly system, and OxyR induces the Suf system to compensate
Authors: Jang Soojin , Imlay James A. 
Published: October 2010

SummaryEnvironmental H2O2 creates several injuries in Escherichia coli, including the oxidative conversion of dehydratase [4Fe–4S] clusters to an inactive [3Fe–4S] form. To protect itself, H2O2‐stressed E. coli activates the OxyR regulon. This regulon includes the suf operon, which encodes an alternative to the housekeeping Isc iron‐sulphur cluster assembly system. Previously studied [3Fe–4S] clusters are repaired by an Isc/Suf‐independent pathway, so the rationale for Suf induction was not obvious. Using strains that cannot scavenge H2O2, we imposed chronic low‐grade stress and found that suf mutants could not maintain the activity of isopropylmalate isomerase, a key iron‐sulphur dehydratase. Experiments showed that its damaged cluster was degraded in vivo beyond the [3Fe–4S] state, presumably to an apoprotein form, and thus required a de novo assembly system for reactivation. Surprisingly, submicromolar H2O2 poisoned the Isc machinery, thereby creating a requirement for Suf both to repair the isomerase and to activate nascent Fe–S enzymes in general. The IscS and IscA components of the Isc system are H2O2‐resistant, suggesting that oxidants disrupt Isc by oxidizing clusters as they are assembled on or transferred from the IscU scaffold. Consistent with these results, organisms that are routinely exposed to oxidants rely upon Suf rather than Isc for cluster assembly.
Phenotypic repertoire of the FNR regulatory network in Escherichia coli
Authors: Tolla Dean A. , Savageau Michael A. 
Published: October 2010

SummaryThe FNR protein in Escherichia coli is an O2 sensor that modifies global gene expression to adapt the cell to anaerobic growth. Regulation of FNR involves continuous cycling of the protein between its active and inactive states under aerobic conditions without apparent function. This raises the question of what benefit to the overall life cycle might compensate for the cost of cycling and reveals that the role of this process is poorly understood. To address this problem, we introduce the concept of a ‘system design space’, which provides a rigorous definition of phenotype at the molecular level and a means of visualizing the phenotypic repertoire of the system. Our analysis reveals undesirable and desirable phenotypes with an optimal constellation of parameter values for the system. To facilitate a more concrete understanding of what the design space represents, we analyse mutations that alter the apparent dimerization rate constant of FNR. We show that our estimated wild‐type value of this rate constant, which is difficult to measure in situ, is located within this constellation and that the behaviour of the system is compromised in mutants if the value of the apparent dimerization rate constant lies beyond the bounds of this optimal constellation.
Mutational analysis of Brh2 reveals requirements for compensating mediator functions
Authors: Kojic Milorad , Zhou Qingwen , Fan Jie , Holloman William K. 
Published: October 2010

SummaryBrh2, a member of the BRCA2 family of proteins, governs homologous recombination in the fungus Ustilago maydis through interaction with Rad51. Brh2 serves at an early step in homologous recombination to mediate Rad51 nucleoprotein filament formation and also has the capability to function at a later step in recombination through its inherent DNA annealing activity. Rec2, a Rad51 paralogue, and Rad52 are additional components of the homologous recombination system, but the absence of either is less critical than Brh2 for operational activity. Here we tested a variety of mutant forms of Brh2 for activity in recombinational repair as measured by DNA repair proficiency. We found that a mutant of Brh2 deleted of the non‐canonical DNA‐binding domain within the N‐terminal region is dependent upon the presence of Rad52 for DNA repair activity. We also determined that a motif first identified in human BRCA2 as important in binding DMC1 also contributes to DNA repair proficiency and cooperates with the BRC element in Rad51 binding.
Cell cycle‐dependent, intercellular transmission of Toxoplasma gondii is accompanied by marked changes in parasite gene expression
Authors: Gaji Rajshekhar Y. , Behnke Michael S. , Lehmann Margaret M. , White Michael W. , Carruthers Vern B. 
Published: October 2010

SummaryIntracellular microbes have evolved efficient strategies for transitioning from one cell to another in a process termed intercellular transmission. Here we show that host cell transmission of the obligate intracellular parasite Toxoplasma gondii is closely tied to specific cell cycle distributions, with egress and reinvasion occurring most proficiently by parasites in the G1 phase. We also reveal that Toxoplasma undergoes marked changes in mRNA expression when transitioning from the extracellular environment to its intracellular niche. These mRNA level changes reflect a modal switch from expression of proteins involved in invasion, motility and signal transduction in extracellular parasites to expression of metabolic and DNA replication proteins in intracellular parasites. Host cell binding and signalling associated with the discharge of parasite secretory proteins was not sufficient to induce this switch in gene expression, suggesting that the regulatory mechanisms responsible are tied to the establishment of the intracellular environment. The genes whose expression increased after parasite invasion belong to a progressive cascade known to underlie the parasite division cycle indicating that the unique relationship between the G1 phase and invasion effectively synchronizes short‐term population growth. This work provides new insight into how this highly successful parasite competently transits from cell to cell.