Staff Nurses’ Perceptions and Experiences about Structural Empowerment: A Qualitative Phenomenological Study

The aim of the study reported in this article was to investigate staff nurses’ perceptions and experiences about structural empowerment and perceptions regarding the extent to which structural empowerment supports safe quality patient care. To address the complex needs of patients, staff nurse involvement in clinical and organizational decision-making processes within interdisciplinary care settings is crucial. A qualitative study was conducted using individual semi-structured interviews of 11 staff nurses assigned to medical or surgical units in a 600-bed university hospital in Belgium. During the study period, the hospital was going through an organizational transformation process to move from a classic hierarchical and departmental organizational structure to one that was flat and interdisciplinary. Staff nurses reported experiencing structural empowerment and they were willing to be involved in decision-making processes primarily about patient care within the context of their practice unit. However, participants were not always fully aware of the challenges and the effect of empowerment on their daily practice, the quality of care and patient safety. Ongoing hospital change initiatives supported staff nurses’ involvement in decision-making processes for certain matters but for some decisions, a classic hierarchical and departmental process still remained. Nurses perceived relatively high work demands and at times viewed empowerment as presenting additional. Staff nurses recognized the opportunities structural empowerment provided within their daily practice. Nurse managers and unit climate were seen as crucial for success while lack of time and perceived work demands were viewed as barriers to empowerment.     

Intergeneric complementation by Agrobacterium tumefaciens chromosomal genes and its potential use for linkage mapping

The IncP1 type plasmids pULB113 (RP4:: mini-Mu) and pJB3JI were used for chromosome mobilization and R prime formation in Agrobacterium tumefaciens. With pULB113, R primes were selected for complementation of an auxotrophic marker in an Alcaligenes eutrophus recipient strain. With pJB3JI, R primes containing the Agrobacterium chromosomal virulence region chv, inactivated by a Tn5 insertion, were constructed. Selection was for kanamycin resistance in E. coli strain GV1000. Complementation tests were performed in auxotrophic A. tumefaciens, A. eutrophus and Pseudomonas fluorescens strains. This allowed us to map 9 loci, including the chv loci, in a region accounting for about 10% of the Agrobacterium chromosome.     

Impurity profiling quality control testing of synthetic peptides using liquid chromatography-photodiode array-fluorescence and liquid chromatography-electrospray ionization-mass spectrometry: the obestatin case

Clinically used low molecular weight heparins (LMWH) are anticoagulants of choice and are phenomenally complex mixtures of millions of distinct natural and unnatural polymeric sequences. The FDA recommends that each LMWH be considered as an independent drug with its own activity profile, placing significant importance on the biophysical characterization of each intact LMWH. We report a robust protocol for fingerprinting these pharmaceutical agents. Capillary electrophoresis of three LMWHs, enoxaparin, tinzaparin, and a Sigma preparation, under reverse polarity conditions in the presence of selected linear alkyl polyamines gives an electrophoretic pattern that is characteristic of the nature of the starting material. The buffers that best provided optimal resolution without compromising sensitivity and speed of analysis were 50 mM sodium phosphate, pH 2.3, and 100 mM ammonium formate, pH 3.5. Resolution was strongly dependent on the structure of polyamine with pentaethylenehexamine being most effective for enoxaparin and Sigma LMWH. In contrast, tinzaparin could be best resolved with tetraethylenepentamine. Cyclic polyamines were ineffective. Resolution was also dependent on the concentration of resolving agents and displayed a narrow window that provides optimal resolution. These features suggest a strong structural origin of the fingerprint pattern. Overall, the simple protocol will find special use in assessing LMWH quality and batch-to-batch variability.     

What Noseleaves Do for FM Bats Depends on Their Degree of Sensorial Specialization

Background

Many bats vocalizing through their nose carry a prominent noseleaf that is involved in shaping the emission beam of these animals. To our knowledge, the exact role of these appendages has not been thoroughly investigated as for no single species both the hearing and the emission spatial sensitivities have been obtained. In this paper, we set out to evaluate the complete spatial sensitivity of two species of New World leaf-nosed bats: Micronycteris microtis and Phyllostomus discolor. From an ecological point of view, these species are interesting as they belong to the same family (Phyllostomidae) and their noseleaves are morphologically similar. They differ vastly in the niche they occupy. Comparing these species allows us to relate differences in function of the noseleaf to the ecological background of bat species.

Methodology/Principal Findings

We simulate the spatial sensitivity of both the hearing and the emission subsystems of two species, M. microtis and P. discolor. This technique allows us to evaluate the respective roles played by the noseleaf in the echolocation system of these species. We find that the noseleaf of M. microtis focuses the radiated energy better and yields better control over the emission beam.

Conclusions

From the evidence presented we conclude that the noseleaves serve quantitatively different functions for different bats. The main function of the noseleaf is to serve as an energy focusing mechanism that increases the difference between the reflected energy from objects in the focal area and objects in the periphery. However, despite the gross morphological similarities between the noseleaves of the two Phyllostomid species they focus the energy to a different extent, a capability that can be linked to the different ecological niches occupied by the two species.     

Sex Differences in Object Manipulation in Wild Immature Chimpanzees (Pan troglodytes schweinfurthii) and Bonobos (Pan paniscus): Preparation for Tool Use?

Sex differences in immatures predict behavioural differences in adulthood in many mammal species. Because most studies have focused on sex differences in social interactions, little is known about possible sex differences in ‘preparation’ for adult life with regards to tool use skills. We investigated sex and age differences in object manipulation in immature apes. Chimpanzees use a variety of tools across numerous contexts, whereas bonobos use few tools and none in foraging. In both species, a female bias in adult tool use has been reported. We studied object manipulation in immature chimpanzees at Kalinzu (Uganda) and bonobos at Wamba (Democratic Republic of Congo). We tested predictions of the ‘preparation for tool use’ hypothesis. We confirmed that chimpanzees showed higher rates and more diverse types of object manipulation than bonobos. Against expectation, male chimpanzees showed higher object manipulation rates than females, whereas in bonobos no sex difference was found. However, object manipulation by male chimpanzees was play-dominated, whereas manipulation types of female chimpanzees were more diverse (e.g., bite, break, carry). Manipulation by young immatures of both species was similarly dominated by play, but only in chimpanzees did it become more diverse with age. Moreover, in chimpanzees, object types became more tool-like (i.e., sticks) with age, further suggesting preparation for tool use in adulthood. The male bias in object manipulation in immature chimpanzees, along with the late onset of tool-like object manipulation, indicates that not all (early) object manipulation (i.e., object play) in immatures prepares for subsistence tool use. Instead, given the similarity with gender differences in human children, object play may also function in motor skill practice for male-specific behaviours (e.g., dominance displays). In conclusion, even though immature behaviours almost certainly reflect preparation for adult roles, more detailed future work is needed to disentangle possible functions of object manipulation during development.     

Isolation and characterization of Neurospora crassa mutants resistant to antifungal plant defensins

Twenty-five Neurospora crassa mutants obtained by chemical mutagenesis were screened for increased resistance to various antifungal plant defensins. Plant defensin-resistant N. crassa mutants were further tested for their cross-resistance towards other families of structurally different antimicrobial peptides. Two N. crassa mutants, termed MUT16 and MUT24, displaying resistance towards all plant defensins tested but not to structurally different antimicrobial peptides were selected for further characterization. MUT16 and MUT24 were more resistant towards plant defensin-induced membrane permeabilization as compared to the N. crassa wild-type. Based on the previously demonstrated key role of fungal sphingolipids in the mechanism of growth inhibition by plant defensins, membrane sphingolipids of MUT16 and MUT24 were analysed. Membranes of these mutants contained structurally different glucosylceramides, novel glycosylinositolphosphorylceramides, and an altered level of steryl glucosides. Evidence is provided to link these clear differences in sphingolipid profiles of N. crassa mutants with their resistance towards different plant defensins.     

SKN1, a novel plant defensin-sensitivity gene in Saccharomyces cerevisiae, is implicated in sphingolipid biosynthesis

The antifungal plant defensin DmAMP1 interacts with the fungal sphingolipid mannosyl diinositolphosphoryl ceramide (M(IP)(2)C) and induces fungal growth inhibition. We have identified SKN1, besides the M(IP)(2)C-biosynthesis gene IPT1, as a novel DmAMP1-sensitivity gene in Saccharomyces cerevisiae. SKN1 was previously shown to be a KRE6 homologue, which is involved in beta-1,6-glucan biosynthesis. We demonstrate that a Deltaskn1 mutant lacks M(IP)(2)C. Interestingly, overexpression of either IPT1 or SKN1 complemented the skn1 mutation, conferred sensitivity to DmAMP1, and resulted in M(IP)(2)C levels comparable to the wild type. These results show that SKN1, together with IPT1, is involved in sphingolipid biosynthesis in S. cerevisiae.     

Cell-Penetrating Peptides Selectively Cross the Blood-Brain Barrier In Vivo

Cell-penetrating peptides (CPPs) are a group of peptides, which have the ability to cross cell membrane bilayers. CPPs themselves can exert biological activity and can be formed endogenously. Fragmentary studies demonstrate their ability to enhance transport of different cargoes across the blood-brain barrier (BBB). However, comparative, quantitative data on the BBB permeability of different CPPs are currently lacking. Therefore, the in vivo BBB transport characteristics of five chemically diverse CPPs, i.e. pVEC, SynB3, Tat 47–57, transportan 10 (TP10) and TP10-2, were determined. The results of the multiple time regression (MTR) analysis revealed that CPPs show divergent BBB influx properties: Tat 47–57, SynB3, and especially pVEC showed very high unidirectional influx rates of 4.73 μl/(g × min), 5.63 μl/(g × min) and 6.02 μl/(g × min), respectively, while the transportan analogs showed a negligible to low brain influx. Using capillary depletion, it was found that 80% of the influxed peptides effectively reached the brain parenchyma. Except for pVEC, all peptides showed a significant efflux out of the brain. Co-injection of pVEC with radioiodinated bovine serum albumin (BSA) did not enhance the brain influx of radiodionated BSA, indicating that pVEC does not itself significantly alter the BBB properties. A saturable mechanism could not be demonstrated by co-injecting an excess dose of non-radiolabeled CPP. No significant regional differences in brain influx were observed, with the exception for pVEC, for which the regional variations were only marginal. The observed BBB influx transport properties cannot be correlated with their cell-penetrating ability, and therefore, good CPP properties do not imply efficient brain influx.     

Nest-Building by Chimpanzees (Pan troglodytes verus) at Seringbara, Nimba Mountains: Antipredation, Thermoregulation, and Antivector Hypotheses

The construction of nests (or beds) for sleeping is a chimpanzee universal, yet little is known about the adaptive function of nest-building. We present an in-depth study of nest-building by unhabituated chimpanzees at the Seringbara study site in the Nimba Mountains, Guinea, West Africa. We recorded 1520 chimpanzee nests over 28 mo during three study periods between 2003 and 2008. We investigated where chimpanzees built their nests, both across the home range and in nest trees, and assessed how altitude and habitat type affected nest site selectivity. We examined whether or not chimpanzees were selective in nest tree choice regarding physical tree characteristics and tree species and assessed plant species preference for both tree- and ground-nesting. We tested three, nonmutually exclusive, hypotheses for the function of arboreal nest-building. We assessed whether selectivity for nest tree characteristics reflected an antipredator strategy, examined whether nesting patterns (both arboreal and terrestrial) and nesting height were influenced by variation in climatic conditions (temperature, humidity, wind), and measured mosquito densities at ground level and in trees at 10 m and related mosquito densities to nesting patterns. Chimpanzees preferred to nest above 1000 m and nested mainly in primary forest. They preferred relatively large trees with a low first branch, dense canopy, and small leaves and showed preference for particular tree species, which was stable across years, whereas plant choice for ground-nesting was largely based on plant availability. We found no support for the antipredation hypothesis, nor did mosquito densities explain arboreal nest-building. The thermoregulation hypothesis was supported, as both nesting patterns and nest-height variation across seasons reflected a humidity-avoidance strategy. Chimpanzees nested higher in trees and at higher altitudes in the wet season. In sum, chimpanzees were selective in their choice of nest sites, locations, and materials, and tree-nesting patterns at Seringbara were best explained by a thermoregulation strategy of humidity avoidance.