Natural sounds can encourage social interactions in urban parks

Urban parks play an essential role in hosting social activities and providing spaces for social interactions. Previous studies have examined the effects of the sound environment on individuals, particularly in terms of perception and behavior; however, few studies have investigated the impact of the sound environment on social interactions in urban parks. In this study, an experiment was conducted involving sound interventions and covert behavioral observations in a typical urban park activity space to determine whether different interventional sounds influence social interaction behaviors. In this experiment, four sound intervention groups and a control group were established and three variables describing the social interaction situation in the study area were defined: proportion of people engaging in social interaction, frequency of social interaction, and percentage of time spent on social interaction. These findings indicate that changes in the sound environment have a significant impact on social interactions. The natural sound intervention was found to increase the proportion of people engaged in social interactions and the frequency and time spent on social interactions. The positive effects of natural sounds primarily promoted social interactions within groups. In addition, the noise interventions in this experiment had no significant negative effects. These findings suggest that protecting and augmenting positive sounds are sometimes more important than noise control and that design strategies that focus on the sound environment could facilitate social interactions in urban park spaces and long-term social cohesion

Comprehensive analyses of DNA methylation profile, regulation on flowering, and seed mineral accumulation in Arabidopsis thaliana in response to zinc deficiency

Zinc (Zn) is an essential micronutrient for plant growth and development, which plays important roles in DNA binding, metabolic, catalytic and transcriptional regulator activities. However, Zn deficiency is a worldwide problem due to its limited bioavailability in soils in many agricultural areas, often as a result of high CaCO3 content and high pH. In addition, phytic acid is able to strongly chelate cations, such as Zn2+, Fe2+, Ca2+ and Mg2+ to form the phytate salts. Phytate cannot be digested by human beings or other monogastric animals due to lack of phytase, an enzyme that can hydrolyze phytate. Therefore, Zn bioavailability in seeds (or grains) is restricted by phytate. Moreover, seed Zn concentration is also reduced by elevated CO2, especially in C3 plants, such as wheat, rice and soybean. Regarding to the crucial roles but limited bioavailability of Zn, here I present a comprehensive analysis on roots, leaves (and flowering) and seeds in response to Zn deficiency in the model plant Arabidopsis thaliana via three experiments. First, I investigated the transcriptional response and whole-genome DNA methylation profile upon Zn deficiency in roots using next-generation sequencing. Ionome analysis on shoots showed that Zn concentration was strongly reduced in Zn deficiency, whereas other nutrients were not affected. Microarray Analysis identified several known Zn-deficiency responsive genes, confirming the effectiveness of Zn deficiency in this work. However, bisulfite sequencing results revealed that DNA methylation was eliminated by Zn deficiency in transposable elements and slightly in gene bodies as well. The DNA demethylation response to nutrient stress was a novel finding, as reversed to previous reports about phosphate stress which accumulated methylation. Surprisingly, further analysis suggested that DNA methylation occurred independent of gene transcription. Nevertheless, non-CpG methylation has a potential impact on flower development in response to Zn deficiency. The second experiment investigated the relationship between rosette size and flowering, and how rosette size and flowering time were regulated by Zn deficiency. Using natural variation population (168 Arabidopsis accessions), I found that flowering time was positively correlated with rosette size in early-flowering accessions but not in late-flowering accessions. Intriguingly, the flowering time was delayed by Zn deficiency in these early-flowering plants and resulting in promotion of vegetative biomass. However, Zn-regulated flowering time was independent of previously reported flowering pathways. Then genome-wide association study identified the underlying candidate gene was FLOWERING LOCUS T (FT) which was strongly inhibited by Zn deficiency in all accessions. Detailed genetic analysis confirmed this result as well. Furthermore, the promotion of leaf size in Zn deficiency was found being contributed by cell proliferation (cell number) but not cell size. Lastly, in the third experiment I was interested in the natural genetic variation in seed Zn concentration, together with iron (Fe) and manganese (Mn), in response to Zn deficiency. Across around 100 accessions, average seed Zn concentration decreased from 47.4 µg g-1 to 31.3 µg g-1 due to Zn deficiency. To identify candidate genes affecting seed Zn, Fe and Mn concentrations, genome-wide association mapping was performed. A candidate gene, inositol 1,3,4-trisphosphate 5/6-kinase 3 gene (ITPK3), was associated which is involved in phytate synthesis pathways. However, loss of this gene in itpk3-1 did neither affect phytate seed levels nor seed Zn, Fe and Mn. Nevertheless, large natural variance of micronutrient seed levels was identified in the population and several accessions maintained high seed Zn despite growth in Zn-deficient conditions. Altogether, this study presents comprehensive analyses in how Arabidopsis adapts to Zn deficiency in regard of root transcription and DNA methylation, flowering and leaf regulation, and seed mineral accumulation. I provided new possibilities of correlation between DNA methylation and gene transcription, which is much more complex than previously reported. I also opened a novel insight into flowering regulation on leaf size, resulting in promotion of vegetative biomass in nutrient deficiency. Substantial natural variation of seed experiment indicated that the evolution process was involved in seed mineral accumulation in Arabidopsis, especially those accessions maintaining Zn concentration in Zn-deficient soils are valuable for further investigations. I believe these findings in Arabidopsis also provide precious knowledge for plant breeders and agronomists who work on crops. Zink (Zn) ist ein essentieller Mikronährstoff für das Wachstum und die Entwicklung einer Pflanze. Seine wesentlichen Funktionen liegen in der Bindung von DNA sowie in metabolischen, katalytischen und transkriptionell regulatorischen Aktivitäten. Aufgrund der begrenzten Bioverfügbarkeit von Zink im Boden, stellt Zinkmangel ein weltweites Problem dar. Vor allem landwirtschaftlich genutzte Böden mit hohen pH-Werten und Kalkgehalten limitieren die Zinkaufnahme. Zusätzlich werden Kationen (wie Zn2+, Fe2+, Ca2+ and Mg2+) von im Boden enthaltenen Phytinsäuren chelatiert und bilden zusammen das schwerlösliche Salz Phytat. Phytat kann nicht von monogastrischen Lebewesen wie dem Menschen aufgespalten werden, da das dazu benötige Enzym Phytase nicht im Verdauungstrakt vorkommt. Die Bioverfügbarkeit von Zn ist deshalb in pflanzlichen Samen durch den Phytatgehalt limitiert. Zudem führt der ansteigende CO2-Gehalt zu einer reduzierten Zn Konzentration im Samen, vor allem in C3-Pflanzen wie Weizen, Reis und Soja. Aufgrund der wichtigen biologischen Funktionen von Zink, aber seiner begrenzten Bioverfügbarkeit, wurden in diesem Forschungsprojekt verschiedene Effekte des Zinkmangels in der Modellpflanze Arabidopsis thaliana genauer analysiert. Zunächst wurden unter Zinkmangel transkriptionelle Veränderungen per Microarray und das genomweite DNA Methylierungsmuster durch genomweite Bisulfit-Sequenzierung in Wurzeln bestimmt. Dabei zeigte die Ionom-Analyse im Spross eine deutlich reduzierte Zn Konzentration in Zinkmangel-ernährten Pflanzen ohne Veränderungen anderer Nährstoffkonzentrationen. Auch die Microarray-Daten belegten einen spezifischen Zinkmangeleffekt durch Expressionsänderungen von mehreren Zinkmangelgenen. Die Ergebnisse der Bisulfit-Sequenzierung wiesen eine Reduzierung der DNA Methylierung durch Zinkmangel auf, welche, wenn vorhanden, hauptsächlich in Transposonelementen und teilweise in kodierenden Genregionen lokalisiert war. Die hier durch Stress verursachte Demethylierung unterschied sich zu bereits beschriebenen Veränderungen der Methylierung durch Phosphormangel dies könnte zu neuen Erkenntnissen im Bereich der epigenetischen Anpassung führen. Interessanterweise zeigten weitere Untersuchungen, dass das DNA Methylierungsmuster keinen direkten Einfluss auf die Genexpression hatte. Nicht-CpG-Methylierungen könnten unter Zinkmangel möglicherweise aber die Blütenentwicklung beeinflussen. Im zweiten Experiment wurde der Zusammenhang zwischen Rosettengröße und Blütezeit unter Zinkmangel bei natürlichen Population von Arabidopsis (168 Akzessionen) genauer untersucht: Bei Frühblüher-Akzessionen korrelierte der Blütezeitpunkt positiv mit der Rosettengröße; Dies traf allerdings nicht bei Spätblütler-Akzessionen zu. Zusätzlich wurde bei diesen Frühblütlern ein bis dato unbekannter, verspäteter Blütezeitpunkt unter Zinkmangel beobachtet, welcher zu einem verstärkten vegetativen Wachstum und dadurch zu einer erhöhten Biomasse führte. Das dafür verantwortliche Gen FLOWERING LOCUS T (FT), das unter Zinkmangel in allen Arabidopsis Akzessionen stark inhibiert war, wurde mittels einer genomweiten Assoziationsstudie identifiziert. Des Weiteren konnte das verstärkte vegetative Blattwachstum unter Zinkmangel auf eine erhöhte Zellproliferation (Zellzahl) und nicht auf eine erhöhte Zellgröße zurückgeführt werden. Im letzten Versuch wurde unter Zinkmangel die natürliche genetische Variation der Zn (sowie Fe und Mn) Konzentration in Samen analysiert. In etwa 100 Akzessionen verringerte sich unter Zinkmangel die durchschnittliche Zn Konzentration im Samen von 47.4 µg g-1 auf 31.3 µg g-1. Eine erneute genomweite Assoziationsstudie identifizierte das Inositol 1,3,4-triphosphate 5/6-kinase 3 (ITPK3) Gen, welches in der Phytatsynthese beteiligt ist, als möglichen Kandidaten für die Beeinflussung der Zn, Fe und Mn Konzentration im Samen. Jedoch führte der Verlust dieses Gens in der iptk-1 Mutante weder zu einem verringerten Phytatgehalt noch zu veränderten Zn, Fe oder Mn Konzentrationen im Samen. Trotz Wachstum auf Zinkmangelboden wurde in der untersuchten Arabidopsis Population ein hoher Mikronährstoffgehalt im Samen quantifiziert und mehrere Akzessionen zeigten sogar trotz Zinkmangel einen hohen Zinkgehalt im Samen, was auf eine evolutionäre Anpassung hindeuten könnte. Zusammengefasst kann gesagt werden, dass diese Studie einen umfassenden Einblick in die Zinkmangelanpassung von Arabidopsis thaliana liefert. Dabei konnten neue Erkenntnisse über die komplexe Beziehung zwischen DNA Methylierung und Genexpression gewonnen werden, über das Blühzeit-beeinflusste vegetative Wachstum und über die natürliche Variation des Mikronährstoffhaushalts im Samen. Diese aus Arabidopsis stammenden Ergebnisse könnten auf Kulturpflanzen übertragbar sein und damit hilfreich für die Züchtung von Kulturpflanzen

Fracture toughness evaluation of a nuclear graphite with non-linear elastic properties by 3D imaging and inverse finite element analysis

Effective small specimen tests are needed to obtain fracture toughness and elastic properties as the limited availability of irradiated graphite restricts the quantity and dimensions of test specimens. Both properties have evaluated simultaneously in a crack propagation test with the double cleavage drilled compression (DCDC) specimen geometry of a fine-grained graphite (SNG742) that has non-linear elastic properties in the unirradiated condition. Three-dimensional displacement fields were obtained by digital volume correlation of in situ laboratory X-ray computed tomographs, and the 3D crack geometry (crack tip position, crack opening displacements and angle) was determined objectively by a wavelet variance method. The tensile softening of the Young modulus was determined by inverse analysis of the strain field using the finite element model updating (FEMU) method. The strain energy release rate of the quasi-static propagating crack was calculated using the contour integral method in a finite element model with the derived non-linear elastic properties and the measured displacements as boundary conditions. The critical strain energy release rate was constant with crack length (118 ± 14 J m−2) and equivalent to a fracture toughness of 1.13 ± 0.07 MPa m1/2

Qualitative Simulation of Photon Transport in Free Space Based on Monte Carlo Method and Its Parallel Implementation

During the past decade, Monte Carlo method has obtained wide applications in optical imaging to simulate photon transport process inside tissues. However, this method has not been effectively extended to the simulation of free-space photon transport at present. In this paper, a uniform framework for noncontact optical imaging is proposed based on Monte Carlo method, which consists of the simulation of photon transport both in tissues and in free space. Specifically, the simplification theory of lens system is utilized to model the camera lens equipped in the optical imaging system, and Monte Carlo method is employed to describe the energy transformation from the tissue surface to the CCD camera. Also, the focusing effect of camera lens is considered to establish the relationship of corresponding points between tissue surface and CCD camera. Furthermore, a parallel version of the framework is realized, making the simulation much more convenient and effective. The feasibility of the uniform framework and the effectiveness of the parallel version are demonstrated with a cylindrical phantom based on real experimental results

Study on Photon Transport Problem Based on the Platform of Molecular Optical Simulation Environment

As an important molecular imaging modality, optical imaging has attracted increasing attention in the recent years. Since the physical experiment is usually complicated and expensive, research methods based on simulation platforms have obtained extensive attention. We developed a simulation platform named Molecular Optical Simulation Environment (MOSE) to simulate photon transport in both biological tissues and free space for optical imaging based on noncontact measurement. In this platform, Monte Carlo (MC) method and the hybrid radiosity-radiance theorem are used to simulate photon transport in biological tissues and free space, respectively, so both contact and noncontact measurement modes of optical imaging can be simulated properly. In addition, a parallelization strategy for MC method is employed to improve the computational efficiency. In this paper, we study the photon transport problems in both biological tissues and free space using MOSE. The results are compared with Tracepro, simplified spherical harmonics method (SPn), and physical measurement to verify the performance of our study method on both accuracy and efficiency

A novel effect of geraniin on OPG/RANKL signaling in osteoblasts

In this study, the effects of geraniin on osteoprotegerin/receptor activator of nuclear factor-κB ligand(OPG/ RANKL) in regulating the proliferation of osteoblasts and suppression of osteoclast-like cells (OLC) in OLC-osteoblast co-cultured system in vitro were investigated. Osteoblasts were cultured and identified with alkaline phosphatase (ALP), gomori stain, and mineralized nodule stain. OLCs were isolated from long bones of Sprague–Dawley (SD) rats and identified with tartrate-resistant acid phosphatase(TRAP) stain. Methyl thiazolyl tetrazolium assay was used to examine the proliferation of osteoblasts, and immunocytochemistry and in situ hybridization to analyze the expression OPG/RANKL in osteoblasts co-cultured with osteoclasts under the action of geraniin, respectively. Geraniin could regulate the proliferation of osteoblasts MC3T3-E1, decrease the number of OLC in OLC-osteoblast co-cultured system, and inhibit the bone resorption areas and resorption pits of OLC in vitro experiments. Geraniin could promote the mRNA and protein expression levels of OPG and suppress those of RANKL in osteoblasts. These results indicate that geraniin has a promoting effect on the proliferation of osteoblasts and an inhibitory effect on the osteoclastic bone-resorption through regulating OPG/RANKL signaling pathway in OLC-OB co-cultured system