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Seasonal shifts in plant diversity effects on above‐ground–below‐ground phenological synchrony
No full textThe significance of biological diversity as a mechanism that optimizes niche breadth for resource acquisition and enhancing ecosystem functionality is well-established. However, a significant gap remains in exploring temporal niche breadth, particularly in the context of phenological aspects of community dynamics. This study takes a unique approach by examining plant phenology, which has traditionally been focused on above-ground assessments, and delving into the relatively unexplored realm of below-ground processes. As a result, the influence of biological diversity on the synchronization of above-ground and below-ground dynamics is brought to the forefront, providing a novel perspective on this complex relationship.In this study, community traits (including plant height and greenness) and soil processes (such as root growth and detritivore feeding activity) were meticulously monitored at 2-week intervals over a year within an experimental grassland exhibiting a spectrum of plant diversity, ranging from monocultures to 60-species mixtures.Our findings revealed that plant diversity increased yearly plant height, root growth and detritivore feeding activity, while enhancing the synchrony between above-ground traits and soil dynamics. Soil microclimate also played a role in shaping the phenology of these traits and processes. However, plant diversity and soil microclimate on above-ground traits and soil dynamics effects varied considerably in strength and direction across seasons, indicating a nuanced relationship between biodiversity, climate and ecosystem processes.Notably, observations during the growing season unveiled a sequential pattern wherein peak plant community height preceded the onset of greenness. Meanwhile, root production commenced immediately after leaf senescence and persisted throughout winter. Although consistent throughout the year, detritivore activity exhibited pronounced peaks in the summer and late fall, albeit with notable variability.Synthesis. The study underscores the dynamic interplay between plant diversity, above-ground–below-ground phenological patterns and ecosystem functioning. It suggests that plant diversity modulates above-ground–below-ground interdependence through intricate phenological dynamics, with the degree of synchrony fluctuating in response to the varying combination of processes and seasonal changes. Thus, by providing comprehensive within-year data, the research elucidates the fundamental disparities in phenological patterns across shoots, roots and soil fauna activities, thereby emphasizing the pivotal role of plant diversity in shaping ecosystem processes
Managing lower extremity loading in distance running by altering sagittal plane trunk leaning
No full textBackgroundTrunk lean angle is an underrepresented biomechanical variable for modulating and redistributing lower extremity joint loading and potentially reducing the risk of running-related overuse injuries. The purpose of this study was to systematically alter the trunk lean angle in distance running using an auditory real-time feedback approach and to derive dose–response relationships between sagittal plane trunk lean angle and lower extremity (cumulative) joint loading to guide overuse load management in clinical practice.MethodsThirty recreational runners (15 males and 15 females) ran at a constant speed of 2.5 m/s at 5 systematically varied trunk lean conditions on a force-instrumented treadmill while kinematic and kinetic data were captured.ResultsA change in trunk lean angle from –2° (extension) to 28° (flexion) resulted in a systematic increase in stance phase angular impulse, cumulative impulse, and peak moment at the hip joint in the sagittal and transversal plane. In contrast, a systematic decrease in these parameters at the knee joint in the sagittal plane and the hip joint in the frontal plane was found (p ConclusionTrunk leaning can reduce knee joint loading and hip joint abduction loading, at the cost of hip joint loading in the sagittal and transversal planes during distance running. Modulating lower extremity joint loading by altering trunk lean angle is an effective strategy to redistribute joint load between/within the knee and hip joints. When implementing anterior trunk leaning in clinical practice, the increased demands on the hip musculature, dynamic stability, and the potential trade-off with running economy should be considered
Biallelic PTPMT1 variants disrupt cardiolipin metabolism and lead to a neurodevelopmental syndrome
No full textPrimary mitochondrial diseases (PMDs) are among the most common inherited neurological disorders. They are caused by pathogenic variants in mitochondrial or nuclear DNA that disrupt mitochondrial structure and/or function, leading to impaired oxidative phosphorylation (OXPHOS). One emerging subcategory of PMDs involves defective phospholipid metabolism. Cardiolipin, the signature phospholipid of mitochondria, resides primarily in the inner mitochondrial membrane, where it is biosynthesized and remodelled via multiple enzymes and is fundamental to several aspects of mitochondrial biology. Genes that contribute to cardiolipin biosynthesis have recently been linked with PMD. However, the pathophysiological mechanisms that underpin human cardiolipin-related PMDs are not fully characterized.Here, we report six individuals, from three independent families, harbouring biallelic variants in PTPMT1, a mitochondrial tyrosine phosphatase required for de novo cardiolipin biosynthesis. All patients presented with a complex, neonatal/infantile onset neurological and neurodevelopmental syndrome comprising developmental delay, microcephaly, facial dysmorphism, epilepsy, spasticity, cerebellar ataxia and nystagmus, sensorineural hearing loss, optic atrophy and bulbar dysfunction. Brain MRI revealed a variable combination of corpus callosum thinning, cerebellar atrophy and white matter changes.Using patient-derived fibroblasts and skeletal muscle tissue, combined with cellular rescue experiments, we characterized the molecular defects associated with mutant PTPMT1 and confirmed the downstream pathogenic effects that loss of PTPMT1 has on mitochondrial structure and function. To further characterize the functional role of PTPMT1 in cardiolipin homeostasis, we created a ptpmt1 knockout zebrafish. This model had abnormalities in body size, developmental alterations, decreased total cardiolipin levels and OXPHOS deficiency.Together, these data indicate that loss of PTPMT1 function is associated with a new autosomal recessive PMD caused by impaired cardiolipin metabolism, highlighting the contribution of aberrant cardiolipin metabolism towards human disease and emphasizing the importance of normal cardiolipin homeostasis during neurodevelopment
How to get it right: a new series in cmi on scientific methodology, practice, and avoiding common mistakes
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Der Einfluss einer Kardiomyozyten-spezifischen Deletion von Sirtuin 5 auf den myokardialen Ischämie-Reperfusionsschaden und auf die mitochondriale Produktion von reaktiven Sauerstoffspezies
No full textMitochondriale Fehlfunktionen tragen wesentlich zur Ausbildung des myokardialen Ischämie-Reperfusionsschadens bei, unter anderem durch ein vermehrtes Aufkommen reaktiver Sauer-stoffspezies (ROS). Sirtuin 5 (SIRT5) ist eine mitochondriale NAD+-abhängige Deacylase, deren fehlende Expression in globalen SIRT5-Knockout-Mäusen zu einem größeren Myokard-schaden nach Ischämie-Reperfusion (IR) führt. Während Vorergebnisse der Arbeitsgruppe zei-gen, dass sich auch Herzen von Kardiomyozyten-spezifischen SIRT5-Knockout-Mäusen nach ex vivo IR in ihrer Funktion schlechter erholen, bleibt bislang unklar, inwiefern ein beobachtetes H2O2-Mehraufkommen dafür ursächlich ist, wie es zu diesem kommt und ob die Funktionsstö-rung der Kardiomyozyten vorübergehend oder von Dauer ist. Ziel dieser Arbeit war es daher, aufbauend auf Vorergebnissen der Arbeitsgruppe den Einfluss einer Kardiomyozyten-spezifischen Deletion von SIRT5 auf den IR-Schaden sowie auf die mitochondriale ROS-Produktion zu untersuchen. Hierfür wurden acht bis elf Wochen alte, männliche Mäuse mit Kardiomyozyten-spezifischem Knockout von SIRT5 (cSIRT5-/-) und entsprechende Wildtyp-Mäuse (WT) untersucht. Der mRNA-Gehalt der antioxidativen Enzyme Katalase, Glutathion-peroxidase 4 und Peroxiredoxin 3 war in Herzen von unbehandelten cSIRT5-/--Mäusen im Vergleich zum WT erhöht. Trotz des erhöhten ROS-Aufkommens nach globaler No-flow-Ischämie im Langendorff-Modell waren die myokardialen Spiegel der Lipidperoxidationspro-dukte Thiobarbitursäure-reaktive Substanzen und 4-Hydroxynonenal jeweils unverändert zwi-schen den Genotypen. Auch die Myokardinfarktgröße nach transienter Ligatur der vorderen Herzkranzarterie in vivo sowie die echokardiographisch bestimmte Ejektionsfraktion nach Myo-kardinfarkt waren nicht unterschiedlich zwischen cSIRT5-/-- und WT-Mäusen. Letztlich konnte auch in H9c2-Zellen mit siRNA-vermittelter Suppression der SIRT5-Expression nach simulier-ter IR keine zusätzliche Abnahme lebender Zellen im Vergleich zu kontrollbehandelten Zellen nachgewiesen werden. Anhand der vorliegenden Ergebnisse wird geschlussfolgert, dass das alleinige Fehlen von SIRT5 in Kardiomyozyten bereits die Erholung der kontraktilen Funktion nach Ischämie im Langendorff-Modell beeinträchtigt. Dies ist mit einem vermehrten Aufkom-men an ROS – am ehesten aufgrund einer erhöhten Produktion – aber nicht mit einer vermehr-ten oxidativen Schädigung assoziiert. Da es nach transienter Koronararterienligatur und auch im isolierten Zellmodell nicht zu einem vermehrten Zelluntergang nach IR kommt, könnte das Feh-len von SIRT5 im Rahmen einer myokardialen IR lediglich zu einer vorübergehenden Funkti-onseinschränkung (= Stunning) führen
Revisiting ice-marginal positions north-east of Feldberg, southern Black Forest, south-west Germany
No full textWhilst previous work has successfully reconstructed the evolution of temperatures in the region north of the Alps during the final phase of the Late Pleistocene, precipitation patterns still remain largely unknown. Recent studies have shown that reconstructing former glaciers in the mid-elevation mountain ranges in central Europe, calculating equilibrium line altitudes (ELAs), and using of empirical relationships between summer temperature and precipitation at the ELAs of modern glaciers could be a promising avenue to fill this gap. Since non-climatic factors probably had only a minor influence on glacier dynamics, the numerous ice-marginal landforms north-east of the highest summit of the Black Forest, Feldberg (1493 m a.s.l. (metres above sea level)), represent prime candidates for climate reconstruction. Since detailed geomorphological and chronological investigations must precede such a study, this work aims to re-examine these landforms with the aid of high-resolution remote sensing data and field mapping. This study allowed for the mapping of glacial landforms in unprecedented detail and for the selection of targets for future dating studies. The re-examination of the glacial record north-east of Feldberg largely confirmed existing studies, and only a few previously mapped ice-marginal landforms must be rejected. At the same time, however, this study identified numerous landforms at former ice-marginal positions that have not yet been described in the literature. These results underline once again that dating studies should always be based on detailed geomorphological mapping. Red-relief image maps (RRIMs) derived from digital elevation models (DEMs) proved to be an extremely helpful visualisation method for the identification of ice-marginal landforms. We therefore advocate for the more frequent use of these maps in glacio-geomorphological studies. Determination of the age of glacial landforms with the aid of cosmic-ray exposure (CRE) dating and luminescence methods will allow for the establishment of an integrated regional stratigraphical model. Once the stratigraphy is constructed, glacier, ELA, and precipitation reconstruction can be undertaken
Feasibility, trueness and precision of intraoral scanners in digitizing maxillectomy defects with exposed zygomatic implants in situ: an in vitro 3D comparative study
No full textSustainable reduction in sound levels on intensive care units through noise management - an implementation study
No full textBackgroundThe noise levels in intensive care units usually exceed the recommended limits in (inter)national recommendations. Such noise levels can affect both the recovery of intensive care patients and the performance of staff. The aim of this study was to reduce ward-based noise levels in three intensive care units (anesthesiological, neurological, and neonatological).MethodsThe implementation of a setting-specific intervention bundle consisting of (a) ward-specific guide to noise management, (b) further noise reduction and prevention measures and (c) the use of “noise traffic lights” was evaluated in an implementation study with a pre-post design. Our primary endpoint was changes in sound level (equivalent continuous sound pressure (LAeq)) 12 weeks after the intervention, and the secondary endpoint was sound level (LAeq), peak sound pressure and maximum sound level at different time points, including changes at 24-week follow-up.ResultsAfter the intervention phase, we observed a significant overall reduction in the sound level of 0.77 decibels (A-weighted) (dB (A)), 95%-CI [0.06, 1.49], p = 0.034 with post-intervention measurements of LAeq1h 56.43 dB (A) compared to pre-intervention measurements of 57.21 dB (A). The difference was particularly large (2.21 dB (A) [p ConclusionsOur implementation study indicates that a bundle of interventions can reduce noise levels in intensive care units, although the clinical relevance of the measured effect must be questioned. Sufficient resources and a participatory approach using an implementation framework should therefore be employed to manage sustainable noise abatement