scholarly journals Distinct effects of pollinator dependence and self-incompatibility on pollen limitation in South African biodiversity hotspots

2016 ◽  
Vol 12 (6) ◽  
pp. 20160253 ◽  
Author(s):  
James G. Rodger ◽  
Allan G. Ellis

Global synthesis indicates that limitation of plant fecundity by pollen receipt (pollen limitation) is positively related to regional plant diversity and is higher for self-incompatible than self-compatible species. While self-incompatible species are always dependent on pollinating agents, self-compatible species may be pollinator-dependent or autofertile. This should cause variation in pollen limitation among self-compatible species, with lower pollen limitation in autofertile species because they do not depend on pollinators. We hypothesized that the intensity of pollen limitation in self-incompatible compared with pollinator-dependent self-compatible species should depend on whether pollen limitation is determined more by quantity than quality of pollen received. We compared pollen limitation between these three groups using a dataset of 70 biotically pollinated species from biodiverse regions of South Africa. Comparison with a global dataset indicated that pollen limitation in the South African biodiversity hotspots was generally comparable to other regions, despite expectations of higher pollen limitation based on the global plant diversity–pollen limitation relationship. Pollen limitation was lowest for autofertile species, as expected. It was also higher for pollinator-dependent self-compatible species than self-incompatible species, consistent with increased pollen-quality limitation in the former group due to negative consequences of pollinator-mediated self-pollination. However, there was a higher frequency of plants with zygomorphic flowers, which were also more pollen-limited, among pollinator-dependent self-compatible species. Thus, we could not attribute this difference in pollen limitation exclusively to a difference in pollen quality. Nevertheless, our results indicate that comparative studies should control for both pollinator dependence and self-incompatiblity when evaluating effects of other factors on pollen limitation.

2008 ◽  
Vol 275 (1637) ◽  
pp. 907-913 ◽  
Author(s):  
Natacha P Chacoff ◽  
Marcelo A Aizen ◽  
Valeria Aschero

A decline in pollination function has been linked to agriculture expansion and intensification. In northwest Argentina, pollinator visits to grapefruit, a self-compatible but pollinator-dependent crop, decline by approximately 50% at 1 km from forest edges. We evaluated whether this decrease in visitation also reduces the pollination service in this crop. We analysed the quantity and quality of pollen deposited on stigmas, and associated limitation of fruit production at increasing distances (edge: 10, 100, 500 and 1000 m) from the remnants of Yungas forest. We also examined the quantitative and qualitative efficiency of honeybees as pollen vectors. Pollen receipt and pollen tubes in styles decreased with increasing distance from forest edge; however, this decline did not affect fruit production. Supplementation of natural pollen with self- and cross-pollen revealed that both pollen quantity and quality limited fruit production. Despite pollen limitation, honeybees cannot raise fruit production because they often do not deposit sufficient high-quality pollen per visit to elicit fruit development. However, declines in visitation frequency well below seven visits during a flower's lifespan could decrease production beyond current yields. In this context, the preservation of forest remnants, which act as pollinator sources, could contribute to resilience in crop production. Like wild plants, pollen limitation of the yield among animal-pollinated crops may be common and indicative not only of pollinator scarcity, but also of poor pollination quality, whereby pollinator efficiency, rather than just abundance, can play a broader role than previously appreciated.


Author(s):  
Jan Christoff Visagie ◽  
Michael M. Jones ◽  
Herman L. Linde

The South African workplace is confronted with many leadership challenges, specifically those relating to the employment relationship between subordinates and their supervisors. A high-quality relationship is essential, considering the work-family spillovers employees experience. Limited research has been conducted on the potential positive and negative consequences of the leader-member exchange (LMX) dyadic relationship. In this study, we used a cross-sectional research design, and drew an employee sample (N = 120) from a commuter transport engineering company. A five-point Likert scale was employed and statistical analyses were carried out using the SAS statistical program. We calculated Pearson correlation coefficients and used structural equation modelling to test the proposed conceptual model to indicate possible correlations between the different variables. The main finding of the study was that the nature of the LMX relationship quality in the relevant company appeared to be high and positively related to work-home enrichment but negatively related to work-home conflict and role overload. The article concludes by making a number of suggestions to respond to challenges.


2020 ◽  
Vol 26 (9) ◽  
pp. 952-956
Author(s):  
M. V. Malyshkina ◽  
M. V. Miroslavskaya

Aim. The presented study aims to develop the methodology for assessing the quality of management of organizational transformation processes. Tasks. To achieve the set aim, the authors solve the following problems: determine the essence and content of socio-economic transformation, formulate quality assurance principles for the management of transformation processes, draw attention to the problem of selecting a unified quality criterion for the management of organizational transformation processes. Methods. This study uses general scientific methods of cognition, including analysis and synthesis. It also applies a systems approach to identify the major problems of assessing the quality of management of transformation processes, including the problem of selecting a unified quality criterion for the management of transformation processes and formulating the principles of ensuring the quality of management of transformation processes. Results. The global problem of managing transformation processes in the economic system consists in the complexity of the managed processes, which increases due to the multidimensionality, mutual influence, and the resulting uncertainty of interactions between the elements of the system. It is concluded that the methodology for assessing the quality of management of transformation processes is based on the principle of integrating separate measures to improve the quality of management of system elements into a single system of management actions and the principle of ensuring that management actions are primarily aimed at preventing possible negative consequences of the transformation of economic systems, i.e. reducing the potential impact of unfavorable events and their consequences. To assess the effectiveness of targeted management actions and productive actions aimed at organizing, controlling, and guiding the transformation process, the authors actualize the problem of selecting an adequate quality criterion for the management of transformation processes in economic systems and put forward a hypothesis about a possible unified criterion of management quality. Conclusions. The principle of integrating separate measures to improve the quality of management of system elements and the principle of ensuring that management actions are aimed at preventing possible negative consequences lie at the core of the methodology for assessing the quality of management of transformation processes in economic systems. The quality assessment methodology should be developed in the direction of finding a unified quality criterion for managing transformation processes in economic systems.


2020 ◽  
pp. 61-73
Author(s):  
Yu. M. Tsygalov

The forced work of Russian universities remotely in the context of the pandemic (COVID-19) has generated a lot of discussion about the benefits of the new form of education. The first results were summed up and reports were presented, the materials of which showed that the main goal of online education — the prevention of the spread of infection, - has been achieved. Against this background, proposals and publications have appeared substantiating the effectiveness of the massive introduction of distance learning in Russia, including in higher education. However, the assessment of such training by the population and students in publications and in social networks was predominantly negative and showed that the number of emerging problems exceeds the possible benefits of the new educational technology. Based on the analysis of the materials of publications and personal experience of teaching online, the potential benefits and problems of distance learning in higher education in Russia are considered. It is proposed to consider the effects separately for the suppliers of new technology (government, universities) and consumers (students, teachers, society). It is substantiated that the massive introduction of online education allows not only to reduce the negative consequences of epidemics, but also to reduce budgetary funding for universities, optimize the age composition of teachers, and reduce the cost of maintaining educational buildings. However, there will be a leveling / averaging of the quality of education, and responsibility for the quality of training will shift from the state/universities to students. The critical shortcomings of online education are the low degree of readiness of the digital infrastructure, the lack of a mechanism for identifying and monitoring the work of students, information security problems, and the lack of trust in such training of the population. The massive use of online education creates a number of risks for the country, the most critical of which is the destruction of the higher education system and a drop in the effectiveness of personnel training. The consequences of this risk realization are not compensated by any possible budget savings.


Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1525
Author(s):  
Christian Ferrarin ◽  
Pierluigi Penna ◽  
Antonella Penna ◽  
Vedrana Spada ◽  
Fabio Ricci ◽  
...  

The aim of this study is to develop a relocatable modelling system able to describe the microbial contamination that affects the quality of coastal bathing waters. Pollution events are mainly triggered by urban sewer outflows during massive rainy events, with relevant negative consequences on the marine environment and tourism and related activities of coastal towns. A finite element hydrodynamic model was applied to five study areas in the Adriatic Sea, which differ for urban, oceanographic and morphological conditions. With the help of transport-diffusion and microbial decay modules, the distribution of Escherichia coli was investigated during significant events. The numerical investigation was supported by detailed in situ observational datasets. The model results were evaluated against water level, sea temperature, salinity and E. coli concentrations acquired in situ, demonstrating the capacity of the modelling suite in simulating the circulation in the coastal areas of the Adriatic Sea, as well as several main transport and diffusion dynamics, such as riverine and polluted waters dispersion. Moreover, the results of the simulations were used to perform a comparative analysis among the different study sites, demonstrating that dilution and mixing, mostly induced by the tidal action, had a stronger effect on bacteria reduction with respect to microbial decay. Stratification and estuarine dynamics also play an important role in governing microbial concentration. The modelling suite can be used as a beach management tool for improving protection of public health, as required by the EU Bathing Water Directive.


2021 ◽  
pp. 019394592199944
Author(s):  
Moataz Mohamed Maamoun Hamed ◽  
Stathis Konstantinidis

Incident reporting in health care prevents error recurrence, ultimately improving patient safety. A qualitative systematic review was conducted, aiming to identify barriers to incident reporting among nurses. Joanna Briggs Institute methodology for qualitative systematic reviews was followed, with data extracted using JBI QARI tools, and selected studies assessed for methodological quality using Critical Appraisal Skills Program (CASP). A meta-aggregation synthesis was carried out, and confidence in findings was assessed using GRADE ConQual. A total of 921 records were identified, but only five studies were included. The overall methodological quality of these studies was good and GRADE ConQual assessment score was “moderate.” Fear of negative consequences was the most cited barrier to nursing incident reporting. Barriers also included inadequate incident reporting systems and lack of interdisciplinary and interdepartmental cooperation. Lack of nurses’ necessary training made it more difficult to understand the importance of incident reporting and the definition of error. Lack of effective feedback and motivation and a pervasive blame culture were also identified.


2016 ◽  
Vol 49 (2) ◽  
pp. 173-186 ◽  
Author(s):  
M. Del Pilar Montero ◽  
Ana Isabel Mora-Urda ◽  
Karim Anzid ◽  
Mohamed Cherkaoui ◽  
M. Dolores Marrodan

SummaryIntra-population socioeconomic changes and migration are powerful factors in changing eating habits. Changes in eating habits could affect the nutritional status, growth, development and health of adolescents. The aim of this study was to compare the diet of adolescents of Moroccan origin living in Spain with that of adolescents living in Morocco. The sample comprised 428 Moroccan adolescents aged from 12 to 19 recruited in high schools: 327 living in Ouarzazate (Morocco) and 101 living in Madrid (Spain). The variables studied were energy intake (kcal/day), diet quality indicators (adherence to the Mediterranean Adequacy Index (MAI); cholesterol intake (mg/day); fibre intake (g/day) and energy profile)); and indicators of keeping traditional customs (halalmeat consumption, bread made at home). Teenagers from Morocco living in Madrid consumed more calories, proteins, saturated fats and simple sugars (p<0.001) than those living in Morocco. Their diet was of lower quality than that of their peers in Morocco. This difference was more marked in boys than in girls. Changes in eating habits associated with migration from the south to the north Mediterranean basin can benefit young migrants in an immediate way (through greater availability of energy and nutrients), but later in life it could have negative consequences for their health, increasing the risk of overweight, obesity and cardiovascular and metabolic problems.


2021 ◽  
pp. 146247452198980
Author(s):  
Vicky Heap ◽  
Alex Black ◽  
Zoe Rodgers

Community Protection Notices (CPNs) are civil preventive orders used in England and Wales to prevent and/or require specific behaviour by an individual or organisation, where existing conduct has a ‘detrimental impact on the quality of life of those in the locality’. Breach of the notice results in a £100 fine under a Fixed Penalty Notice or a possible criminal conviction. To date, CPNs have tackled an array of perceived anti-social behaviours, ranging from rough sleeping to overgrown gardens. Using Ashworth and Zedner’s preventive justice as an analytical framework, our research qualitatively explores recipients’ experiences of this new tool for the first time. The findings highlight how the operationalisation of CPNs extends the coercive power of the state, with a range of negative consequences relating to the concepts of disproportionality, due process and accountability. We also offer three empirically-grounded recommendations for reforming CPN practices.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Fabrizio Luppi ◽  
Meena Kalluri ◽  
Paola Faverio ◽  
Michael Kreuter ◽  
Giovanni Ferrara

AbstractIdiopathic pulmonary fibrosis (IPF) is a chronic and progressive disorder with an estimated median survival time of 3–5 years after diagnosis. This condition occurs primarily in elderly subjects, and epidemiological studies suggest that the main risk factors, ageing and exposure to cigarette smoke, are associated with both pulmonary and extrapulmonary comorbidities (defined as the occurrence of two or more disorders in a single individual). Ageing and senescence, through interactions with environmental factors, may contribute to the pathogenesis of IPF by various mechanisms, causing lung epithelium damage and increasing the resistance of myofibroblasts to apoptosis, eventually resulting in extracellular matrix accumulation and pulmonary fibrosis. As a paradigm, syndromes featuring short telomeres represent archetypal premature ageing syndromes and are often associated with pulmonary fibrosis. The pathophysiological features induced by ageing and senescence in patients with IPF may translate to pulmonary and extrapulmonary features, including emphysema, pulmonary hypertension, lung cancer, coronary artery disease, gastro-oesophageal reflux, diabetes mellitus and many other chronic diseases, which may lead to substantial negative consequences in terms of various outcome parameters in IPF. Therefore, the careful diagnosis and treatment of comorbidities may represent an outstanding chance to improve quality of life and survival, and it is necessary to contemplate all possible management options for IPF, including early identification and treatment of comorbidities.


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