Konkurrenz zwischen Stieleiche und Buche auf Lothar-Sturmflächen | Competition between pedunculate oak and European beech on Lothar windthrow areas

The competitive pressure of naturally regenerated European beech (Fagus sylvatica) saplings on planted pedunculate oak (Quercus robur) was investigated on two 1.8 ha permanent plots near Habsburg and Murten (Switzerland). The plots were established with the aim to test methods of artificial oak regeneration after large-scale windthrow. On both plots, 80 oaks exposed to varying levels of competitive pressure from at most 10 neighbouring beech trees were selected. The height of each oak as well as stem and branch diameters were measured. The competitive pressure was assessed using Schütz's competition index, which is based on relative tree height, crown overlap and distance from competing neighbours. Oak trees growing without or with only slight competition from beech were equally tall, while oaks exposed to moderate to strong competition were smaller. A threshold value for the competition index was found above which oak height decreased strongly. The stem and branch diameters of the oaks started to decrease even if the competition from beech was slight, and decreased much further with more competition. The oak stems started to become more slender even with only slight competition from beech. On the moderately acid beech sites studied here, beech grow taller faster than oak. Thus where beech is competing with oak and the aim is to maintain the oak, competitive pressure on the oak must be reduced at an early stage. The degree of the intervention should, however, take the individual competitive interaction into account, with more intervention if the competition is strong.

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Study on the Threshold Value and Test Methods for Chloride Ion Content in Sea Sand

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.680.482 ◽

2016 ◽

Vol 680 ◽

pp. 482-485

Author(s):

Fei Long Sun ◽

Shuai Wu ◽

Quan Jiang ◽

Ting Ting Liu

Keyword(s):

Early Stage ◽

Chloride Ion ◽

Threshold Value ◽

Test Methods ◽

Chloride Ions ◽

International Standards ◽

National Standards ◽

Ion Content ◽

River Sand ◽

Sea Sand

The building sand is mainly composed of river sand at early stage. Recently, with the depletion of river sand, the new mined river sand cannot meet the demands for building sand. The sea sand is resourceful and can remedy the deficiency of sand for construction. However, the sea sand contains high content of chlorine salt, shell and lightweight matters. They are harmful for the strength and durability of concrete and will lead to premature corrosion of rebar. This will endanger the safety of construction. The studies demonstrate that high content of chlorine salt in sea sand is the main factor led to the deterioration of sea sand concrete. Therefore, in order to ensure the safety of construction, the threshold value of chloride content is specified in standards about concrete and aggregate. And methods testing the content of chloride ions are provided. However, the criterion in different standards differs from one another, which means their different viewpoints about the harm of chloride ions. In this work, the threshold value and test methods of chloride ion content for the building sand in the national standards and the international standards are summarized. The research has great significant for setting standards about sea sand, determining the rational threshold value of chloride ion content and improving the method testing the content of chloride ions.

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Allometric Equations for Estimating Biomass and Carbon Stocks in Afforested Open Woodlands with Black Spruce and Jack Pine, in the Eastern Canadian Boreal Forest

Forests ◽

10.3390/f12010059 ◽

2021 ◽

Vol 12 (1) ◽

pp. 59

Author(s):

Olivier Fradette ◽

Charles Marty ◽

Pascal Tremblay ◽

Daniel Lord ◽

Jean-François Boucher

Keyword(s):

Large Scale ◽

Ad Hoc ◽

Black Spruce ◽

Tree Height ◽

Jack Pine ◽

Carbon Stocks ◽

Allometric Equations ◽

C Stocks ◽

The Difference ◽

Canadian Boreal Forest

Allometric equations use easily measurable biometric variables to determine the aboveground and belowground biomasses of trees. Equations produced for estimating the biomass within Canadian forests at a large scale have not yet been validated for eastern Canadian boreal open woodlands (OWs), where trees experience particular environmental conditions. In this study, we harvested 167 trees from seven boreal OWs in Quebec, Canada for biomass and allometric measurements. These data show that Canadian national equations accurately predict the whole aboveground biomass for both black spruce and jack pine trees, but underestimated branches biomass, possibly owing to a particular tree morphology in OWs relative to closed-canopy stands. We therefore developed ad hoc allometric equations based on three power models including diameter at breast height (DBH) alone or in combination with tree height (H) as allometric variables. Our results show that although the inclusion of H in the model yields better fits for most tree compartments in both species, the difference is minor and does not markedly affect biomass C stocks at the stand level. Using these newly developed equations, we found that carbon stocks in afforested OWs varied markedly among sites owing to differences in tree growth and species. Nine years after afforestation, jack pine plantations had accumulated about five times more carbon than black spruce plantations (0.14 vs. 0.80 t C·ha−1), highlighting the much larger potential of jack pine for OW afforestation projects in this environment.

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Favorable Effects of GLP-1 Receptor Agonist against Pancreatic β-Cell Glucose Toxicity and the Development of Arteriosclerosis: “The Earlier, the Better” in Therapy with Incretin-Based Medicine

International Journal of Molecular Sciences ◽

10.3390/ijms22157917 ◽

2021 ◽

Vol 22 (15) ◽

pp. 7917

Author(s):

Hideaki Kaneto ◽

Tomohiko Kimura ◽

Masashi Shimoda ◽

Atsushi Obata ◽

Junpei Sanada ◽

...

Keyword(s):

Large Scale ◽

Cell Function ◽

Apoptotic Cell ◽

Early Stage ◽

Insulin Biosynthesis ◽

Protective Effects ◽

Pancreatic Β Cell ◽

Β Cells ◽

Β Cell ◽

Glucose Toxicity

Fundamental pancreatic β-cell function is to produce and secrete insulin in response to blood glucose levels. However, when β-cells are chronically exposed to hyperglycemia in type 2 diabetes mellitus (T2DM), insulin biosynthesis and secretion are decreased together with reduced expression of insulin transcription factors. Glucagon-like peptide-1 (GLP-1) plays a crucial role in pancreatic β-cells; GLP-1 binds to the GLP-1 receptor (GLP-1R) in the β-cell membrane and thereby enhances insulin secretion, suppresses apoptotic cell death and increase proliferation of β-cells. However, GLP-1R expression in β-cells is reduced under diabetic conditions and thus the GLP-1R activator (GLP-1RA) shows more favorable effects on β-cells at an early stage of T2DM compared to an advanced stage. On the other hand, it has been drawing much attention to the idea that GLP-1 signaling is important in arterial cells; GLP-1 increases nitric oxide, which leads to facilitation of vascular relaxation and suppression of arteriosclerosis. However, GLP-1R expression in arterial cells is also reduced under diabetic conditions and thus GLP-1RA shows more protective effects on arteriosclerosis at an early stage of T2DM. Furthermore, it has been reported recently that administration of GLP-1RA leads to the reduction of cardiovascular events in various large-scale clinical trials. Therefore, we think that it would be better to start GLP-1RA at an early stage of T2DM for the prevention of arteriosclerosis and protection of β-cells against glucose toxicity in routine medical care.

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Modelling natural regeneration of European beech in Saxony, Germany: identifying factors influencing the occurrence and density of regeneration

European Journal of Forest Research ◽

10.1007/s10342-021-01377-w ◽

2021 ◽

Author(s):

Maximilian Axer ◽

Sven Martens ◽

Robert Schlicht ◽

Sven Wagner

Keyword(s):

Natural Regeneration ◽

Negative Binomial ◽

European Beech ◽

Seed Source ◽

Permanent Plots ◽

Forest Conversion ◽

Ecological Knowledge ◽

Statistical Tool ◽

Factors Influencing ◽

The Impact

AbstractThe potential utilisation of natural regeneration of European beech (Fagus sylvatica L.) for forest conversion has received little attention to date. Ecological knowledge is necessary to understand and predict successful natural regeneration of beech. The objective of this study was to improve understanding of what drives the occurrence of beech regeneration and, once regeneration is present, what drives its density. In the study, we utilised a forest inventory dataset provided by Sachsenforst, the state forestry service of Saxony, Germany. The dataset was derived from 8725 permanent plots. Zero-altered negative binomial models (ZANB) with spatial random effects were used to analyse factors influencing occurrence and density simultaneously. The results provided by the spatial ZANB models revealed that the probability of the occurrence of beech regeneration is highly dependent on seed availability, i.e. dependent on source trees in close proximity to a plot. The probability of beech regeneration rises with the increasing diameter of a potential seed tree and decreases with increasing distance to the nearest potential seed source. The occurrence of regeneration is affected by overstorey composition and competition exerted by spruce regeneration. Where sites are affected by groundwater or temporary waterlogging, the impact on the occurrence of regeneration is negative. Although distance to the nearest potential seed source has an influence on occurrence, this variable exerts no influence on density. A high regeneration density arises in conjunction with a high beech basal area in the overstorey. Beech regeneration density, but not occurrence, is negatively affected by browsing intensity. These variables can be used to predict the occurrence and density of beech regeneration in space to a high level of precision. The established statistical tool can be used for decision-making when planning forest conversion using natural regeneration.

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Understanding the Processes Causing the Early Intensification of Hurricane Dorian through an Ensemble of the Hurricane Analysis and Forecast System (HAFS)

Atmosphere ◽

10.3390/atmos12010093 ◽

2021 ◽

Vol 12 (1) ◽

pp. 93

Author(s):

Andrew Hazelton ◽

Ghassan J. Alaka ◽

Levi Cowan ◽

Michael Fischer ◽

Sundararaman Gopalakrishnan

Keyword(s):

Tropical Cyclone ◽

Large Scale ◽

Early Stage ◽

Early Period ◽

Storm Track ◽

Key Factors ◽

Complex Interplay ◽

Forecast System ◽

Model Initialization

The early stages of a tropical cyclone can be a challenge to forecast, as a storm consolidates and begins to grow based on the local and environmental conditions. A high-resolution ensemble of the Hurricane Analysis and Forecast System (HAFS) is used to study the early intensification of Hurricane Dorian, a catastrophic 2019 storm in which the early period proved challenging for forecasters. There was a clear connection in the ensemble between early storm track and intensity: stronger members moved more northeast initially, although this result did not have much impact on the long-term track. The ensemble results show several key factors determining the early evolution of Dorian. Large-scale divergence northeast of the tropical cyclone (TC) appeared to favor intensification, and this structure was present at model initialization. There was also greater moisture northeast of the TC for stronger members at initialization, favoring more intensification and downshear development of the circulation as these members evolved. This study highlights the complex interplay between synoptic and storm scale processes in the development and intensification of early-stage tropical cyclones.

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Cytotoxic Profiling of Annotated and Diverse Chemical Libraries Using Quantitative High-Throughput Screening

SLAS DISCOVERY Advancing Life Sciences ◽

10.1177/2472555219873068 ◽

2019 ◽

Vol 25 (1) ◽

pp. 9-20 ◽

Cited By ~ 2

Author(s):

Olivia W. Lee ◽

Shelley Austin ◽

Madison Gamma ◽

Dorian M. Cheff ◽

Tobie D. Lee ◽

...

Keyword(s):

Cell Lines ◽

Cancer Cell ◽

High Throughput ◽

High Throughput Screening ◽

Drug Targets ◽

Large Scale ◽

Early Stage ◽

Cancer Cell Line ◽

Hek 293 ◽

Cytotoxic Compounds

Cell-based phenotypic screening is a commonly used approach to discover biological pathways, novel drug targets, chemical probes, and high-quality hit-to-lead molecules. Many hits identified from high-throughput screening campaigns are ruled out through a series of follow-up potency, selectivity/specificity, and cytotoxicity assays. Prioritization of molecules with little or no cytotoxicity for downstream evaluation can influence the future direction of projects, so cytotoxicity profiling of screening libraries at an early stage is essential for increasing the likelihood of candidate success. In this study, we assessed the cell-based cytotoxicity of nearly 10,000 compounds in the National Institutes of Health, National Center for Advancing Translational Sciences annotated libraries and more than 100,000 compounds in a diversity library against four normal cell lines (HEK 293, NIH 3T3, CRL-7250, and HaCat) and one cancer cell line (KB 3-1, a HeLa subline). This large-scale library profiling was analyzed for overall screening outcomes, hit rates, pan-activity, and selectivity. For the annotated library, we also examined the primary targets and mechanistic pathways regularly associated with cell death. To our knowledge, this is the first study to use high-throughput screening to profile a large screening collection (>100,000 compounds) for cytotoxicity in both normal and cancer cell lines. The results generated here constitute a valuable resource for the scientific community and provide insight into the extent of cytotoxic compounds in screening libraries, allowing for the identification and avoidance of compounds with cytotoxicity during high-throughput screening campaigns.

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Development of a Reproducible Method of Formulating and Testing Drilling Fluids

Society of Petroleum Engineers Journal ◽

10.2118/2302-pa ◽

1969 ◽

Vol 9 (04) ◽

pp. 403-411 ◽

Cited By ~ 2

Author(s):

B.K. Sinha ◽

Harvey T. Kennedy

Keyword(s):

Large Scale ◽

Drilling Fluid ◽

Flow Characteristics ◽

Field Testing ◽

Test Methods ◽

Water Evaporation ◽

Fluid Loss ◽

Drilling Fluids ◽

Testing Procedures ◽

Asymptotic Values

Abstract Recommendations are made for obtaining consistent and reproducible test data on drilling fluids having identical composition. Previously, such a procedure has been difficult to accomplish even when the fluids were mixed in similar equipment. A survey of work in this area indicates that previous methods have been unsatisfactory because previous methods have been unsatisfactory because (1) the muds are extremely sensitive to the duration and violence of agitation during a normal mixing routine, and (2) gelling of the muds occurs before the properties can reach constant values. This gelling is caused by water evaporation resulting from the increase in temperature associated with the agitation. The work shows that these problems largely can be overcome by (1) agitating the constituents of the drilling fluid more vigorously, (2) maintaining a fairly constant temperature, and(3) Protecting the fluid from evaporation. When these steps are followed, the fluid properties approach asymptotic values that do not change by prolonged or accelerated agitation or by aging for a month. The time required to reach asymptotic values or a stabilized state is from 2 to 6 hours and is a function of the mud composition. Introduction Preparation of drilling fluids in the laboratory to determine their suitability to meet specific drilling requirements or to serve as a base fluid to evaluate the effectiveness of thinners, dispersants or other additives normally begins with combining measured quantities of the constituents and stirring them for a short time in a low-speed mixer. This is done to obtain a uniform mixture and to hydrate clays. Then the fluid is further agitated in a higher-speed device (Hamilton Beach mixer or Waring blender) to disperse more thoroughly and clay particles The biggest obstacle in the laboratory investigation of drilling fluids has been the lack of a method of producing a mixture by which reproducible results of the measured properties could be obtained. Numerous investigators have encountered this difficulty. Prior to 1929, density was the only property of mud that customarily was measured. The use of Wyoming bentonite on a large scale after 1929 was mainly responsible for the development of more elaborate testing procedures and for the application of the principles of colloid chemistry to the drilling fluids. Ambrose and Loomis in 1931 were among the first to recognize the plastic flow characteristics of drilling fluids, although Bingham in 1916 had observed The same phenomenon with dilute clay suspensions. Marsh introduced the Marsh funnel for field testing in 1931. By this time, non-Newtonian characteristics of drilling fluids were established. The Stormer and MacMichael viscometers were used to study the rheological properties of the fluids. In the 1930's and early 1940's, the work conducted by several investigators contributed toward a better understanding of drilling fluids. In the mid 1930's, fluid-loss and the associated mud-cake-forming properties of drilling fluids were recognized as important to the behavior of these fluids. The other properties of drilling fluids, including gel strength, pH, and sand content soon were recognized. In 1937, API published its first recommended procedure for test methods. Since that time, these procedures have been revised periodically. The latest edition, RP-13B, was published in 1961 However, in spite of the recognized need for a method of mixing that provides drilling fluids with stabilized properties, no such method previously has been described. SPEJ P. 403

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Separation of Fe from Mn in the Cryogenian Sedimentary Mn Deposit, South China: Insights from Ore Mineral Chemistry and S Isotopes from the Dawu Deposit

Minerals ◽

10.3390/min11050446 ◽

2021 ◽

Vol 11 (5) ◽

pp. 446

Author(s):

Zhiming Xu ◽

Chengquan Wu ◽

Zhengwei Zhang ◽

Jinhong Xu ◽

Xiyao Li ◽

...

Keyword(s):

South China ◽

Large Scale ◽

Early Stage ◽

Sulfur Isotopes ◽

Mineral Chemistry ◽

Manganese Carbonate ◽

Separation Mechanism ◽

Geochemical Properties ◽

Stage Separation ◽

Fe Content

Manganese and Fe have similar geochemical properties in the supergene environment. Separation of Mn and Fe is an important process for the formation of high-grade sedimentary manganese deposits. Large-scale manganese carbonate deposits (total reserves of approximately 700 Mt) were formed during the interglacial of the Sturtian and Marinoan in South China. The orebodies are hosted in the black rock series at the basal Datangpo Formation of the Cryogenian period. The Fe contents in ores range from 1.15 to 7.18 wt.%, with an average of 2.80 wt.%, and the average Mn/Fe ratio is 8.9, indicating a complete separation of Mn and Fe during the formation of manganese ores. Here, we present element data of manganese carbonates and sulfur isotopes of pyrite from the Dawu deposit, Guizhou, China, aiming to investigate the separation mechanism of Mn and Fe and the ore genesis. The Fe in ores mainly occurs as carbonate (FeCO3) and pyrite (FeS2). The Mn, Ca, Mg and Fe exist in the form of isomorphic substitutions in manganese carbonate. The contents of FeCO3 in manganese carbonates are similar in different deposits, with averages of 2.6–2.8 wt.%. The whole-rock Fe and S contents have an obvious positive correlation (R = 0.69), indicating that the difference of whole-rock Fe content mainly comes from the pyrite content. The δ34SV-CDT of pyrite varies from 40.0 to 48.3‰, indicating that the pyrite formed in a restricted basin where sulfate supply was insufficient and the sulfate concentrations were extremely low. Additionally, the whole-rock Fe content is negatively correlated with the δ34S values of the whole-rock and pyrite, with correlation coefficients of −0.78 and −0.83, respectively. Two stages of separations of Mn and Fe might have occurred during the mineralization processes. The reduced seawater became oxidized gradually after the Sturtian glaciation, and Fe2+ was oxidized and precipitated before Mn2+, which resulted in the first-stage separation of Mn and Fe. The residual Mn-rich and Fe-poor seawater flowed into the restricted rift basin. Mn and Fe were then precipitated in sediments as oxyhydroxide as the seawater was oxidized. At the early stage of diagenesis, organic matter was oxidized, and manganese oxyhydroxide was reduced, forming the manganese carbonate. H2S was insufficient in the restricted basin due to the extremely low sulfate concentration. The Fe2+ was re-released due to the lack of H2S, resulting in the second-stage separation of Mn and Fe. Finally, the manganese carbonate deposit with low Fe and very high δ34S was formed in the restricted basin after the Sturtian glaciation.

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Accessing Voluntary HIV Testing in the Construction Industry: A Qualitative Analysis of Employee Interviews from the Test@Work Study

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18084184 ◽

2021 ◽

Vol 18 (8) ◽

pp. 4184

Author(s):

Sarah Somerset ◽

Catrin Evans ◽

Holly Blake

Keyword(s):

Sexual Health ◽

Hiv Testing ◽

Construction Industry ◽

Large Scale ◽

Early Stage ◽

Structured Interview ◽

Health Check ◽

Public Health Issue ◽

Health Awareness ◽

Health Checks

HIV, globally, remains a significant public health issue and community HIV testing can help to identify those with HIV at an early stage of disease. The workplace offers a prime location for provision of opt-in HIV testing as part of wider health promotion initiatives. The construction industry offers a key opportunity for HIV testing provision in a generally male-dominated group exhibiting some risky behaviors related to HIV. The intervention was an optional one-off individual health check with tailored health advice and signposting, offered to the construction workforce in health check events delivered as part of a large-scale multi-site research program called Test@Work. The events were undertaken at 10 participating organizations (21 events across 16 different sites), none had previously offered sexual health awareness or HIV testing to their workforce. Participants were invited to participate in a semi-structured interview following general health checks which included HIV testing. Out of 426 employees attending the health check events, 338 (79.3%) consented to interview on exit. Accessing HIV testing at work was valued because it was convenient, quick, and compatible with work demands. Interviewees identified HIV risks for construction including drug use, high numbers of sexual partners and job-related exposures, e.g., to used needles. Health seeking in construction was limited by stigma and low support, with particular barriers for non-permanent workers. The organization of the construction industry is complex with multiple organizations of different sizes having responsibility for varying numbers of employees. A disparity between organizational policies and employment circumstances is evident, and this generates significant health inequalities. To combat this, we recommend that organizations in the construction sector offer their employees awareness-raising around health behaviors and health protection in packages, such as toolbox talks. We recommend these be accompanied by annual health checks, including sexual health awareness and opt-in workplace HIV testing. This approach is highly acceptable to the workforce in the industry and removes barriers to access to healthcare.

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Machine learning of serum metabolic patterns encodes early-stage lung adenocarcinoma

10.21203/rs.3.pex-963/v1 ◽

2021 ◽

Author(s):

Lin Huang ◽

Kun Qian

Keyword(s):

Machine Learning ◽

Lung Adenocarcinoma ◽

Cancer Detection ◽

High Performance ◽

Large Scale ◽

Early Cancer ◽

Early Stage ◽

Early Cancer Detection ◽

Ionization Mass ◽

Efficient Test

Abstract Early cancer detection greatly increases the chances for successful treatment, but available diagnostics for some tumours, including lung adenocarcinoma (LA), are limited. An ideal early-stage diagnosis of LA for large-scale clinical use must address quick detection, low invasiveness, and high performance. Here, we conduct machine learning of serum metabolic patterns to detect early-stage LA. We extract direct metabolic patterns by the optimized ferric particle-assisted laser desorption/ionization mass spectrometry within 1 second using only 50 nL of serum. We define a metabolic range of 100-400 Da with 143 m/z features. We diagnose early-stage LA with sensitivity~70-90% and specificity~90-93% through the sparse regression machine learning of patterns. We identify a biomarker panel of seven metabolites and relevant pathways to distinguish early-stage LA from controls (p < 0.05). Our approach advances the design of metabolic analysis for early cancer detection and holds promise as an efficient test for low-cost rollout to clinics.

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