The intensity paradox:A systematic review and meta‐analysis of its impact on the cardiorespiratory fitness of older adults

Aim: The present systematic review and meta‐analysis aimed to compare the effect of moderate‐ versus high‐intensity aerobic exercise on cardiorespiratory fitness (CRF) in older adults, taking into account the volume of exercise completed. Methods: The databases MEDLINE (Ovid), EMBASE (Ovid), and CENTRAL (Cochrane Library) were searched to identify randomized controlled trials (RCTs). Two reviewers extracted data and assessed bias. Comprehensive Meta‐Analysis software calculated overall effect size, intensity differences, and performed meta‐regression analyses using pre‐to‐post intervention or change scores of peak oxygen uptake (V̇O2peak). The review included 23 RCTs with 1332 older adults (intervention group: n = 932; control group: n = 400), divided into moderate‐intensity (435 older adults) and high‐intensity (476 older adults) groups. Results: Meta‐regression analysis showed a moderate, but not significant, relationship between exercise intensity and improvements in V̇O2peak after accounting for the completed exercise volume (β = 0.31, 95% CI = [−0.04; 0.67]). Additionally, studies comparing moderate‐ versus high‐intensity revealed a small, but not significant, effect in favor of high‐intensity (Hedges' g = 0.20, 95% CI = [−0.02; 0.41]). Finally, no significant differences in V̇O2peak improvements were found across exercise groups employing various methods, modalities, and intensity monitoring strategies. Conclusion: Findings challenge the notion that high‐intensity exercise is inherently superior and indicate that regular aerobic exercise, irrespective of the specific approach and intensity, provides the primary benefits to CRF in older adults. Future RCTs should prioritize valid and reliable methodologies for monitoring and reporting exercise volume and adherence among older adults

THE LINK BETWEEN STAKEHOLDER POWER AND VALUE CREATION IN CONSTRUCTION PROJECTS

ABSTRACT This paper presents a study on what effect stakeholder power has on value creation in construction projects. Fourteen main sources of power in organizations, described by Morgan, form the analytic framework. The ambition is to identify 1) how the distribution of power between the main stakeholders is, 2) which sources of power are most common in a construction project organization, 3) which effect the sources of power have on value creation in projects. The data is collected through semi-structured interviews. Experienced representatives from four main stakeholders in early phase of construction projects (owner, architect, design manager and project manager) were interviewed. The collected data through the interviews was coded, analyzed and linked to the literature study. The results reveals that 10 of 14 sources of power are identified as common sources of power in construction project organizations. Out of the ten, control of knowledge & information and formal authority are rated as the most influential sources of power. Apparently, all main stakeholders can possess these two sources. Rhetorical skills -which is not among the fourteen main sources described by Morgan -turn out to be an underrated and complex source of power. The LCI triangle model suggests that all project delivery systems have three basic domains whining which they operate i) organization, ii) the project´s "Operating system" and iii) the commercial terms binding the participants. These are equally important and should be aligned for the system to be coherent. Power is one of the main elements in organizational affairs that effect transparency and decision processes. There is a knowledge gap in how the power can affect the processes in project organization and which effects it can have on the projects´ overall value creation

Communication in Building Design Management: A Comparative Study of Norway and Germany

ABSTRACT First-rate communication between design and construction site teams is imperative for the successful completion of architecture, engineering and construction (AEC) projects. Still, research carried out in Norwegian and German industry has identified a lack of literature and qualitative research in this area. Equally, there seems to be a tendency to underestimate the correlation between communication and efficiency in most construction projects. By addressing different factors affecting communication, reasons for communication, communication networks, communication channels and future needs in a comparative way, this paper aims to increase knowledge about and understanding of communication in the design-construction interface. An extensive literature review, a document study and indepth interviews were carried out, according to a qualitative approach. The findings are limited to the investigated cases. However, they do imply that there is a need for a better understanding of communication both in Norway and in Germany. Additionally, the research revealed a lack of knowledge and training in the use of ICT tools and team frameworks. By increasing the awareness of the communication challenges that exists, this study can help AEC practitioners and academics to solve communication problems between design and construction site teams

Bacterial Leaf Symbiosis in Angiosperms: Host Specificity without Co-Speciation

Bacterial leaf symbiosis is a unique and intimate interaction between bacteria and flowering plants, in which endosymbionts are organized in specialized leaf structures. Previously, bacterial leaf symbiosis has been described as a cyclic and obligate interaction in which the endosymbionts are vertically transmitted between plant generations and lack autonomous growth. Theoretically this allows for co-speciation between leaf nodulated plants and their endosymbionts. We sequenced the nodulated Burkholderia endosymbionts of 54 plant species from known leaf nodulated angiosperm genera, i.e. Ardisia, Pavetta, Psychotria and Sericanthe. Phylogenetic reconstruction of bacterial leaf symbionts and closely related free-living bacteria indicates the occurrence of multiple horizontal transfers of bacteria from the environment to leaf nodulated plant species. This rejects the hypothesis of a long co-speciation process between the bacterial endosymbionts and their host plants. Our results indicate a recent evolutionary process towards a stable and host specific interaction confirming the proposed maternal transmission mode of the endosymbionts through the seeds. Divergence estimates provide evidence for a relatively recent origin of bacterial leaf symbiosis, dating back to the Miocene (5–23 Mya). This geological epoch was characterized by cool and arid conditions, which may have triggered the origin of bacterial leaf symbiosis

The evolution and storage of primitive melts in the Eastern Volcanic Zone of Iceland: the 10 ka Grímsvötn tephra series (i.e. the Saksunarvatn ash)

Major, trace and volatile elements were measured in a suite of primitive macrocrysts and melt inclusions from the thickest layer of the 10 ka Grímsvötn tephra series (i.e. Saksunarvatn ash) at Lake Hvítárvatn in central Iceland. In the absence of primitive tholeiitic eruptions (MgO > 7 wt.%) within the Eastern Volcanic Zone (EVZ) of Iceland, these crystal and inclusion compositions provide an important insight into magmatic processes in this volcanically productive region. Matrix glass compositions show strong similarities with glass compositions from the AD 1783–84 Laki eruption, confirming the affinity of the tephra series with the Grímsvötn volcanic system. Macrocrysts can be divided into a primitive assemblage of zoned macrocryst cores (An_78–An_92, Mg#_cpx = 82–87, Fo_79.5–Fo_87) and an evolved assemblage consisting of unzoned macrocrysts and the rims of zoned macrocrysts (An_60–An_68, Mg#_cpx = 71–78, Fo_70–Fo_76). Although the evolved assemblage is close to being in equilibrium with the matrix glass, trace element disequilibrium between primitive and evolved assemblages indicates that they were derived from different distributions of mantle melt compositions. Juxtaposition of disequilibrium assemblages probably occurred during disaggregation of incompatible trace element-depleted mushes (mean La/Yb_melt = 2.1) into aphyric and incompatible trace element-enriched liquids (La/Yb_melt = 3.6) shortly before the growth of the evolved macrocryst assemblage. Post-entrapment modification of plagioclase-hosted melt inclusions has been minimal and high-Mg# inclusions record differentiation and mixing of compositionally variable mantle melts that are amongst the most primitive liquids known from the EVZ. Coupled high field strength element (HFSE) depletion and incompatible trace element enrichment in a subset of primitive plagioclase-hosted melt inclusions can be accounted for by inclusion formation following plagioclase dissolution driven by interaction with plagioclase-undersaturated melts. Thermobarometric calculations indicate that final crystal-melt equilibration within the evolved assemblage occurred at ~1140°C and 0.0–1.5 kbar. Considering the large volume of the erupted tephra and textural evidence for rapid crystallisation of the evolved assemblage, 0.0–1.5 kbar is considered unlikely to represent a pressure of long-term magma accumulation and storage. Multiple thermometers indicate that the primitive assemblage crystallised at high temperatures of 1240–1300°C. Different barometers, however, return markedly different crystallisation depth estimates. Raw clinopyroxene-melt pressures of 5.5–7.5 kbar conflict with apparent melt inclusion entrapment pressures of 1.4 kbar. After applying a correction derived from published experimental data, clinopyroxene-melt equilibria return mid-crustal pressures of 4±1.5 kbar, which are consistent with pressures estimated from the major element content of primitive melt inclusions. Long-term storage of primitive magmas in the mid-crust implies that low CO_2 concentrations measured in primitive plagioclase-hosted inclusions (262–800 ppm) result from post-entrapment CO_2 loss during transport through the shallow crust. In order to reconstruct basaltic plumbing system geometries from petrological data with greater confidence, mineral-melt equilibrium models require refinement at pressures of magma storage in Iceland. Further basalt phase equilibria experiments are thus needed within the crucial 1–7 kbar range.D.A.N. was supported by a Natural Environment Research Council studentship (NE/1528277/1) at the start of this project. SIMS analyses were supported by Natural Environment Research Council Ion Microprobe Facility award (IMF508/1013).This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s00410-015-1170-

Tephrochronology

Tephrochronology is the use of primary, characterized tephras or cryptotephras as chronostratigraphic marker beds to connect and synchronize geological, paleoenvironmental, or archaeological sequences or events, or soils/paleosols, and, uniquely, to transfer relative or numerical ages or dates to them using stratigraphic and age information together with mineralogical and geochemical compositional data, especially from individual glass-shard analyses, obtained for the tephra/cryptotephra deposits. To function as an age-equivalent correlation and chronostratigraphic dating tool, tephrochronology may be undertaken in three steps: (i) mapping and describing tephras and determining their stratigraphic relationships, (ii) characterizing tephras or cryptotephras in the laboratory, and (iii) dating them using a wide range of geochronological methods. Tephrochronology is also an important tool in volcanology, informing studies on volcanic petrology, volcano eruption histories and hazards, and volcano-climate forcing. Although limitations and challenges remain, multidisciplinary applications of tephrochronology continue to grow markedly