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2.
J Phys Chem A ; 127(18): 4015-4026, 2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37129861

RESUMEN

This paper reports on computational studies of gas-phase reactions of SiO and Si2O2. The oxidation of SiO can initiate efficient formation of silica or silicate dust particles in a wide range of environments. Both OH radicals and H2O molecules are often present in these environments, and their reactions with SiO and the smallest SiO cluster, Si2O2, affect the efficiency of eventual dust formation. Density functional theory calculations on these reactions, benchmarked against accurate coupled cluster calculations, indicate that the Si2O2 + OH reaction should be faster than SiO + OH. The reaction SiO + H2O → SiO2 + H2 is both endothermic and has high activation energies to reaction. Instead, the formation of molecular complexes is efficient. The reaction of Si2O2 with H2O, which has been suggested as efficient for producing Si2O3, might not be as efficient as previously thought. If the H2O molecules dissociate to form OH radicals, oxidation of SiO and Si2O2 could be accelerated instead.

3.
Proc Natl Acad Sci U S A ; 120(1): e2203228120, 2023 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-36580593

RESUMEN

Understanding the causes and limits of population divergence in phenotypic traits is a fundamental aim of evolutionary biology, with the potential to yield predictions of adaptation to environmental change. Reciprocal transplant experiments and the evaluation of optimality models suggest that local adaptation is common but not universal, and some studies suggest that trait divergence is highly constrained by genetic variances and covariances of complex phenotypes. We analyze a large database of population divergence in plants and evaluate whether evolutionary divergence scales positively with standing genetic variation within populations (evolvability), as expected if genetic constraints are evolutionarily important. We further evaluate differences in divergence and evolvability-divergence relationships between reproductive and vegetative traits and between selfing, mixed-mating, and outcrossing species, as these factors are expected to influence both patterns of selection and evolutionary potentials. Evolutionary divergence scaled positively with evolvability. Furthermore, trait divergence was greater for vegetative traits than for floral (reproductive) traits, but largely independent of the mating system. Jointly, these factors explained ~40% of the variance in evolutionary divergence. The consistency of the evolvability-divergence relationships across diverse species suggests substantial predictability of trait divergence. The results are also consistent with genetic constraints playing a role in evolutionary divergence.


Asunto(s)
Adaptación Fisiológica , Evolución Biológica , Reproducción , Fenotipo , Aclimatación , Plantas/genética , Variación Genética , Flores/genética
4.
Health Res Policy Syst ; 20(1): 135, 2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36527014

RESUMEN

BACKGROUND: Public involvement in health and social care research is increasingly prioritized by policy-makers and research funders. Often, the impact of the involvement is described in terms of how it has contributed to the research outcomes and how it has affected the involved members of the public. There is a dearth of studies reporting from the perspective of researchers themselves of having involved members of the public in their research. Nevertheless, there is a general expectation for researchers to accept and embrace public involvement in research. This study aims to explore researchers' views of involving informal carers in health and social care research. METHODS: Eleven individual in-depth interviews with researchers in the fields of social work, caring science, health science and medical science constituted the dataset of this qualitative study, inspired by discourse psychology. RESULTS: The qualitative data analysis resulted in two interpretative repertoires describing researchers' views of involving informal carers in research, "Philosophy of Science" and "Personal relationships and growth". Both repertoires need to be recognized; however, as of today, the Philosophy of Science repertoire is more acknowledged, while the second repertoire describing empathy, relationships and emotions may be viewed as the researcher being "unprofessional". Further, the findings highlighted the dual perspective of being a researcher and a carer as creating opportunities for growth on the part of the researcher, on both a professional and a personal level. CONCLUSIONS: Researchers and their research work would benefit from acknowledging, discussing and reporting both interpretative repertoires in their publications, as well as recognizing the benefit of dialectal positions, for example, having a dual perspective as both a researcher and an informal carer.


Asunto(s)
Cuidadores , Apoyo Social , Humanos , Cuidadores/psicología , Investigación Cualitativa , Investigadores , Servicio Social
5.
J Environ Qual ; 51(6): 1235-1245, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36099508

RESUMEN

Nitrogen (N) and phosphorus (P) losses, via both surface runoff and subsurface drainage water, were monitored in an agricultural field in northern Sweden for 32 yr. The objective was to determine losses of N and P in a long-term perspective in relation to meteorological factors and impacts of agricultural land use, with a focus on relative contributions of surface runoff and subsurface drainage water to N and P losses. In order to collect surface runoff water, an embankment was installed on three sides of the field, and the fourth side had an open ditch that drove runoff water to a measuring station. Subsurface water draining from the field was collected in a fishbone-shaped drainage system that terminated at the measuring station. In 50% of years (16/32), mean annual concentration of total N (TN) was significantly higher in subsurface drainage water than in surface runoff water. An opposing trend was seen for total P (TP), with mean annual concentration being significantly higher in surface runoff water than in subsurface drainage water in all but 3 of the 32 yr monitored. Years with a barley crop had higher TN concentration in subsurface drainage water but no difference in surface runoff compared with years with ley. In contrast, years with barley had lower TN concentration in surface runoff than years with ley, with no difference in TP in subsurface drainage water.


Asunto(s)
Fósforo , Movimientos del Agua , Suecia , Fósforo/análisis , Agricultura , Nitrógeno/análisis , Nutrientes , Agua
6.
Geriatr Nurs ; 47: 171-182, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35926339

RESUMEN

Mealtimes are important events in care homes for physical and social well-being. However, residents usually have little input concerning meal timings, what food is offered, and how it is served. This integrative review explored mealtime interventions and their outcomes in care homes related to the Five Aspects Meal Model (FAMM). Research articles published 2010-2021 were searched for in ASSIA, CINAHL, PsycINFO, PubMed, and SveMed+ and resulted in 13 articles focusing on interventions. The analysis was based on the aspects of FAMM: room, meeting, product, management control system, and atmosphere. The result shows that even though interventions specifically focused on one aspect, they often evaluated outcomes related to several aspects. Different aspects can work together to foster effective mealtimes. FAMM eased to visualise the usefulness of mealtime interventions from a broad perspective and can be a useful tool for assessing and improving mealtime situations in clinical practice.


Asunto(s)
Servicios de Alimentación , Comidas , Anciano , Servicios de Alimentación/organización & administración , Hogares para Ancianos/organización & administración , Humanos , Factores de Tiempo
7.
Phys Chem Chem Phys ; 24(14): 8378-8386, 2022 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-35332892

RESUMEN

Using molecular dynamics and path sampling techniques we investigated the effect of pressure and defects in the wurtzite to rock salt transition in cadmium selenide (CdSe). In the pressure range 2-10 GPa, rate constants of transition are in the order of 10-23 to 105 s-1 for the transformation of a relatively small wurtzite crystal consisting of 1024 atoms with periodic boundary conditions. The transition paths predominantly evolve through an intermediate 5-coordinated structure, as reported before, though its typical lifetime within the transition paths is particularly long in the intermediate pressure range (4-6 GPa). The defects were created by removing Cd-Se pairs from an otherwise perfect crystal. The removals were either selected fully randomized or grouped in clusters (cavity creation). We find that the rate of transition due to the defects increases by several orders of magnitude even for a single pair removal. This is caused by a change in the transition mechanism that no longer proceeds via the intermediate 5-coordinated structure, when defects are present. Further, the cavity creation yields a lower rate than the fully randomized removal.

8.
Res Involv Engagem ; 7(1): 80, 2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34749834

RESUMEN

BACKGROUND: Due to demographic changes and a strained public sector operating in many countries globally, informal care is increasing. Currently, at least 1.3 million adults in Sweden regularly provide help, support and/or care to a family member/significant other. With no sign of an imminent decrease in their caring activities, it is important that informal carers are considered as a key stakeholder group within research that affects them, e.g., the co-design of carer and/or dyadic support interventions. The objective of this descriptive, quantitative study was to investigate informal carers' perceived motivations and obstacles to become involved in research. METHODS: A cross-sectional survey design was adopted, using first-wave data from a panel study. The data, collected in Sweden between September 2019 and March 2020, included survey responses from 147 informal carers who were either aged 60+ years themselves or were caring for someone who was aged 60+ years. RESULTS: Our main results showed that informal carers are, in general, interested in research. Slightly fewer were interested in becoming actively involved themselves, but older age was the only characteristic significantly associated with less interest of being actively involved. Two latent motivational dimensions emerged from the factor analysis: 'family motivation' and 'the greater good motivation'. These, according to our results, almost equally valued dimensions, described the differing reasons for informal carers to become involved in research. The most common perceived obstacle was lack of time and it was reported by more women than men. CONCLUSION: Our study contributes with new knowledge of informal carers' perceived motivations and obstacles regarding carer involvement in research. Paying attention to the differing motivational dimensions held by informal carers could help researchers create conditions for more inclusive and systematic participation of informal carers within research. Thereby, increasing the opportunities for research that is deemed to be of higher societal impact. IRRID (International Registered Report Identifier): RR2-10.2196/17759.


Around 1.3 million adults in Sweden give help, support and care to an ill, aged or disabled family member, neighbour or friend. As informal carers contribute a lot to our societies, it is important to recognise them and, where possible, to involve them in research that affects them, together with patients and professionals. The rationale for our study is the current lack of studies on carers' views of being involved in research. 147 carers aged 60+, or who were caring for a person 60+ answered a survey that asked about carers' motivations for and obstacles to being actively involved in research. By actively involved, we mean that participation was more than filling in a questionnaire or one single interview. We found that carers are, in general, interested in research. Slightly fewer were interested in becoming actively involved themselves. Older age was the only characteristic associated with less interest of being actively involved. A statistical test showed two motivational categories; 'family motivation' and 'the greater good motivation'. These almost equally valued categories described the different reasons for carers to become involved in research. The most common obstacle was lack of time and more women than men reported this. This study adds new knowledge about carer involvement in research. The results of our study could help researchers to create a more supportive climate for actively involving carers in research. For example, by finding more flexible and creative ways to recruit carers and carry out research with them.

9.
Langmuir ; 37(24): 7473-7485, 2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34098717

RESUMEN

The evaporation of P from liquid Si under vacuum and reduced pressures of H2, He, and Ar was studied to evaluate the feasibility of effective P removal with insignificant Si loss. It was found that the introduction of Ar and He inert gases at low pressures reduces the rate of P removal, and their pressure decrease will increase the process rate. Moreover, the kinetics of P removal was higher in He than in Ar, with simultaneous lower Si loss. Under reduced pressures of H2 gas, however, the P removal rate was higher than that under vacuum conditions with the lowest Si loss. Quantum chemistry and dynamics simulations were applied, and the results indicated that P can maintain its momentum for longer distances in H2 once it is evaporated from the melt surface and then can travel far away from the surface, while Si atoms lose their momentum in closer distances, yielding less net Si flux to the gas phase. Moreover, this distance is significantly increased with decreasing pressure for H2, He, and Ar gases; however, it is the largest for H2 and the lowest for Ar for a given pressure, while the temperature effect is insignificant. The rate of P evaporation was accelerated by applying an additional vacuum tube close to the melt surface for taking out the hot gas particles before they lose their temperature and velocity. It was shown that this technique contributes to the rate of process by preventing condensing gas stream back to the melt surface.

10.
Health Sci Rep ; 4(1): e225, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33392394

RESUMEN

BACKGROUND AND AIMS: There is a growing demand for health and social care services to provide technology-mediated interventions that promote the health and well-being of older people with health or care needs and of their informal carers. The objectives of this study were to scope and review the nature and extent of prior intervention studies involving ambient assisted living technology-mediated interventions for older people and their informal carers, and how and in what ways (if any) the goals and aims of these interventions reflected the domains of the World Health Organization framework for healthy ageing. METHODS: We conducted a scoping review. Data were collected between June and October 2018 with an updated search in October 2020. A total of 85 articles were eligible for inclusion. RESULTS: Nine categories described the aims and content of the included studies. The healthy ageing domain "Ability to meet basic needs" was mirrored in four categories, whereas "Ability to contribute to society" was not addressed at all. CONCLUSION: The ways in which domains of healthy ageing are mirrored suggest that there is an emphasis on individual factors and individual responsibility, and a lack of attention given to broader, environmental factors affecting healthy ageing. Only a few of the studies used a dyadic approach when assessing health outcomes concerning older people and their informal carers.

11.
J Phys Chem A ; 125(1): 387-393, 2021 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-33370120

RESUMEN

Binding energies of the CH3O radical on hexagonal water ice (Ih) and amorphous solid water (ASW) were calculated using the ONIOM(QM:MM) method. A range of binding energies is found (0.10-0.50 eV), and the average binding energy is 0.32 eV. The CH3O radical binding on the ASW surfaces is stronger than on the Ih surfaces. The computed binding energies from the ONIOM(wB97X-D/def2-TZVP:AMBER) and wB97X-D/def2-TZVP methods agree quite well. Therefore, the ONIOM(QM:MM) method is expected to give accurate binding energies at a low computational cost. Binding energies from the ONIOM(wB97X-D/def2-TZVP:AMBER) and ONIOM(wB97X-D/def2-TZVP:AMOEBA09) methods differ noticeably, indicating that the choice of force field matters. According to the energy decomposition analysis, the electrostatic interactions and Pauli repulsions between the CH3O radical and ice play a crucial role in the binding energy. This study gives quantitative insights into the CH3O radical binding on interstellar ices.

12.
J Evol Biol ; 33(10): 1452-1467, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33463845

RESUMEN

Mate choice in plants is poorly understood, in particular its indirect genetic benefits, but also the direct benefits of avoiding harmful matings. In the herb Collinsia heterophylla, delayed stigma receptivity has been suggested to enhance pollen competition, potentially functioning as a female mate choice trait. Previous studies show that this trait can mitigate the cost of early fertilization caused by pollen, thus providing a direct benefit. We performed two-donor pollinations during successive floral stages to assess how this stigma receptivity trait and two pollen traits known to affect siring success influence indirect benefits in terms of offspring performance. We also investigated differential resource allocation by studying the influence of sibling performance in the same capsule. Offspring performance in terms of flower number was mainly affected by parental identities and differential resource allocation. Offspring seed production showed some influence of resource allocation, but was also affected by pollen donor identity and varied positively with late stigma receptivity. However, the effect of late stigma receptivity on offspring seed production was weakened in matings with pollen that advanced stigma receptivity. In conclusion, delayed stigma receptivity may be selected through both direct and indirect fitness effects in C. heterophylla, where pollen-based delay on stigma receptivity might act as a cue for mate choice. However, selection may also be counteracted by antagonistic selection on pollen to advance stigma receptivity. Our results highlight the challenges of studying indirect genetic benefits and other factors that influence mate choice in plants.


Asunto(s)
Flores/fisiología , Aptitud Genética , Plantaginaceae/genética , Polinización , Selección Genética , Polen , Semillas/crecimiento & desarrollo
13.
J Environ Qual ; 48(4): 941-949, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31589675

RESUMEN

The winter climate in northwestern Europe is commonly influenced by the North Atlantic Oscillation (NAO). Its intensity, expressed as an index (NAO), has been suggested for use in assessing nutrient leaching from arable land to water and the effects of mitigation measures. We found significant ( < 0.05) positive linear relationships between NAO and an air freezing-thawing index in central and southern Sweden for 2004 to 2016. This period covered winters with both extreme low and high NAO. There were significant negative linear relationships between NAO and a snow depth index. Management and nutrient leaching were studied simultaneously in two agricultural catchments (20.7 ha, code 11M; 788 ha, code M36) in southwestern Sweden. Catchments 11M (silty-clay soil) and M36 (sandy hills with a central, heavy clay plain) are both artificially drained. Total N and total P leaching increased significantly with winter (November-April) NAO in both catchments. In contrast, leaching of dissolved reactive P (DRP) was not related to NAO. The highest DRP concentrations were observed in connection with specific agricultural practices, whereas moderately elevated DRP concentrations were linked to snowmelt events. Concentrations of P in other forms (other P) were even more elevated (1.02 mg L) in 11M in winter 2014-2015, probably due to a large (32% of area) internal buffer (ley-fallow) in a central ravine being plowed down in autumn 2014. No general trend in P or N fertilization was found in catchment M36. Thus NAO may be appropriate for use in trend analyses of nutrient load in the study region.


Asunto(s)
Clima , Nutrientes , Estaciones del Año , Suelo , Suecia
14.
Scand J Caring Sci ; 31(3): 487-496, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27481631

RESUMEN

Policy makers in Sweden and other European Member States pay increasing attention as to how best support working carers; carers juggling providing unpaid family care for older family members while performing paid work. Exploring perceived benefits and challenges with web-based information and communication technologies as a means of supporting working carers' in their caregiving role, this paper draws on findings from a qualitative study. The study aimed to describe working carers' experiences of having access to the web-based family care support network 'A good place' (AGP) provided by the municipality to support those caring for an older family member. Content analysis of interviews with nine working carers revealed three themes: A support hub, connections to peers, personnel and knowledge; Experiencing ICT support as relevant in changing life circumstances; and Upholding one's personal firewall. Findings indicate that the web-based family care support network AGP is an accessible, complementary means of support. Utilising support while balancing caregiving, work obligations and responsibilities was made easier with access to AGP; enabling working carers to access information, psychosocial support and learning opportunities. In particular, it provided channels for carers to share experiences with others, to be informed, and to gain insights into medical and care issues. This reinforced working carers' sense of competence, helping them meet caregiving demands and see positive aspects in their situation. Carers' low levels of digital skills and anxieties about using computer-based support were barriers to utilising web-based support and could lead to deprioritising of this support. However, to help carers overcome these barriers and to better match web-based support to working carers' preferences and situations, web-based support must be introduced in a timely manner and must more accurately meet each working carer's unique caregiving needs.


Asunto(s)
Cuidadores/psicología , Familia , Internet , Apoyo Social , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Suecia
15.
Chemphyschem ; 17(24): 4079-4089, 2016 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-27649519

RESUMEN

Ground-state geometries of benzene on crystalline ice cluster model surfaces (Ih ) are investigated. It is found that the binding energies of benzene-bound ice complexes are sensitive to the dangling features of the binding sites. We used time-dependent DFT to study the UV spectroscopy of benzene, ice clusters, and benzene-ice complexes, by employing the M06-2X functional. It is observed that the size of the ice cluster and the dangling features have minor effects on the UV spectral characteristics. Benzene-mediated electronic excitations of water towards longer wavelengths (above 170 nm) are noted in benzene-bound ice clusters, where the cross-section of photon absorption by water is negligible, in good agreement with recent experimental results (Thrower et al., J. Vac. Sci. Technol. A, 2008, 26, 919-924). The intensities of peaks associated with water excitations in benzene-ice complexes are found to be higher than in isolated ice clusters. The π→π* electronic transition of benzene in benzene-ice complexes undergoes a small redshift compared with the isolated benzene molecule, and this holds for all benzene-bound ice complexes.

16.
PLoS One ; 11(7): e0160191, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27462709

RESUMEN

Although genotype-by-environment interaction has long been used to unveil the genetic variation that affects Darwinian fitness, the mechanisms underlying the interaction usually remain unknown. Genetic variation at the dimeric glycolytic enzyme phosphoglucoisomerase (Pgi) has been observed to interact with temperature to explain the variation in the individual performance of the butterfly Melitaea cinxia. At relatively high temperature, individuals with Pgi-non-f genotypes generally surpass those with Pgi-f genotypes, while the opposite applies at relatively low temperature. In this study, we did protein structure predictions and BlastP homology searches with the aim to understand the structural basis for this temperature-dependent difference in the performance of M. cinxia. Our results show that, at amino acid (AA) site 372, one of the two sites that distinguish Pgi-f (the translated polypeptide of the Pgi-f allele) from Pgi-non-f (the translated polypeptide of the Pgi-non-f allele), the Pgi-non-f-related residue strengthens an electrostatic attraction between a pair of residues (Glu373-Lys472) that are from different monomers, compared to the Pgi-f-related residue. Further, BlastP searches of animal protein sequences reveal a dramatic excess of electrostatically attractive combinations of the residues at the Pgi AA sites equivalent to sites 373 and 472 in M. cinxia. This suggests that factors enhancing the inter-monomer interaction between these two sites, and therefore helping the tight association of two Pgi monomers, are favourable. Our homology-modelling results also show that, at the second AA site that distinguishes Pgi-f from Pgi-non-f in M. cinxia, the Pgi-non-f-related residue is more entropy-favourable (leading to higher structural stability) than the Pgi-f-related residue. To sum up, this study suggests a higher structural stability of the protein products of the Pgi-non-f genotypes than those of the Pgi-f genotypes, which may explain why individuals carrying Pgi-non-f genotypes outperform those carrying Pgi-f genotypes at stressful high temerature.


Asunto(s)
Mariposas Diurnas/genética , Genotipo , Calor , Proteínas de Insectos/genética , Polimorfismo Genético , Animales , Aptitud Genética , Proteínas de Insectos/química , Simulación de Dinámica Molecular , Mutación Missense , Estabilidad Proteica
17.
Chemphyschem ; 17(18): 2908-15, 2016 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-27303941

RESUMEN

To further understanding of the role of sodium in carbon cathode degradation in Hall-Héroult cells, potential-energy surfaces and charge-transfer curves are presented for finite-size complexes of sodium intercalated between various polycyclic aromatic hydrocarbons. Calculations for lithium and potassium are included to highlight the disparate intercalation behaviour of the alkali metals in graphite intercalation compounds. Static energy barriers from DFT are used to compute macroscopic diffusion coefficients according to transition-state theory. Comparing the calculated diffusion coefficient to experimental values from the literature sheds light on the role of lattice diffusion of sodium-graphite intercalation compounds in sodium intrusion in graphitic carbon cathodes.

18.
Phytopathology ; 106(8): 877-83, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27070426

RESUMEN

Nongenetic inheritance (e.g., transgenerational epigenetic effects) has received increasing interest in recent years, particularly in plants. However, most studies have involved a few model species and relatively little is known about wild species in these respects. We investigated transgenerational induced resistance to infection by the devastating oomycete Phytophthora infestans in Solanum physalifolium, a wild relative of cultivated potato. We treated plants with ß-aminobutyric acid (BABA), a nontoxic compound acting as an inducing agent, or infected plants with P. infestans. BABA treatment reduced lesion size in detached-leaf assays inoculated by P. infestans in two of three tested genotypes, suggesting that resistance to oomycetes can be induced by BABA within a generation not only in crops or model species but also in wild species directly collected from nature. Both BABA treatment and infection in the parental generation reduced lesions in the subsequent generation in one of two genotypes, indicating a transgenerational influence on resistance that varies among genotypes. We did not detect treatment effects on seed traits, indicating the involvement of a mechanism unrelated to maternal effects. In conclusion, our study provides data on BABA induction and nongenetic inheritance of induced resistance in a wild relative of cultivated potato, implying that this factor might be important in the ecological and agricultural landscape.


Asunto(s)
Phytophthora , Enfermedades de las Plantas/microbiología , Solanum/microbiología , Aminobutiratos , Epigénesis Genética , Predisposición Genética a la Enfermedad , Semillas
19.
Am J Bot ; 103(3): 541-52, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26542842

RESUMEN

PREMISE OF THE STUDY: Although much attention has focused on the diversity of plant mating systems, only a few studies have considered the joint effects of mating system and sexual conflict in plant evolution. In mixed-mating Collinsia heterophylla, a sexual conflict over timing of stigma receptivity is proposed: pollen with a capacity to induce early onset of stigma receptivity secures paternity for early-arriving pollen (at the expense of reduced maternal seed set), whereas late onset of stigma receptivity mitigates the negative effects of early-arriving pollen. Here we investigated whether selection on pollen and pistil traits involved in sexual conflict is affected by the presence of both outcross- and self-pollen (mixed mating) during pollen competition. METHODS: We conducted two-donor crosses at different floral developmental stages to explore male fitness (siring ability) and female fitness (seed set) in relation to male and female identity, pollen and pistil traits, and type of competitor pollen (outcross vs. self). KEY RESULTS: Late-fertilizing pollen rather than rapidly growing pollen tubes was most successful in terms of siring success, especially in competition with self-pollen after pollination at early floral stages. Late stigma receptivity increased seed set after early-stage pollinations, in agreement with selection against antagonistic pollen. CONCLUSIONS: Selection on pollen and pistil traits in C. heterophylla is affected by both sexual conflict and mixed mating, suggesting the importance of jointly considering these factors in plant evolution.


Asunto(s)
Plantago/fisiología , Plantas Medicinales/fisiología , Polen/fisiología , Polinización , Carácter Cuantitativo Heredable , Autofecundación/fisiología , Cruzamientos Genéticos , Modelos Biológicos , Semillas/fisiología
20.
Int J Older People Nurs ; 11(1): 32-43, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26073289

RESUMEN

BACKGROUND: Family care support services have mainly focused on older spousal carers of older people and have largely overlooked working carers, whom combine paid work with informal/family care responsibilities. Recently, however, information and communication technology (ICT) systems have been identified as a potentially flexible way of supporting working carers. AIM: The aim of this study was to describe nursing and support staff's experiences of using ICT for information, e-learning and support of working carers of older people. DESIGN: The study employed a descriptive, qualitative approach conducting a qualitative secondary analysis of two original data sets. In total, seventeen professional staff members from two municipal family carer support units in Sweden that had implemented ICTs were interviewed using a semi-structured interview guide consisting of open-ended questions. METHOD: Two data sets were merged using latent qualitative content analysis. FINDINGS: Secondary analysis produced three subthemes and an overall theme, a virtual road as a carriageway for the support of working carers, consisting of both enabling and hindering aspects in family support. This theme provides access points in both directions and is based on caring instruments that enable nursing staff's support role. The staff's sustainability and ability to support is influenced by caring opportunities and barriers. CONCLUSIONS: The findings suggest the ICTs to be flexible structures that provided nursing staff with a means and method to support working carers of older people. To overcome barriers to its use, measures to optimise support for working carers and the older person are needed. IMPLICATIONS FOR PRACTICE: The use of ICTs provides nurses with a means to offer support to working carers of older people and enables carers to be informed, to learn and to share their burdens with others when caring for an older family member.


Asunto(s)
Cuidadores , Redes de Comunicación de Computadores , Internet , Apoyo Social , Anciano , Empleo , Humanos , Entrevistas como Asunto , Evaluación de Programas y Proyectos de Salud , Suecia
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