Variation of the tree ring micro-hardness demonstrated on spruce wood

Micro-hardness was used for the study of wood structure (Norway spruce) in the line perpendicular to tree rings (radial surface). The steel indentor 0.25 mm in diameter with flat head was used for this purpose. The individual penetration tests were performed at constant velocity 0.0167 mm/sinto a depth of 0.3 mm. Local wood strength was defined as the mean pressure on the indentor head at 0.02 mm penetration. The set of tests (~ 320) gave information about stress variation in dependence on the location of the test place in the tested surface. The stress was understood as a parameter describing the growth properties of wood similarly like the density usually used in dendrochronology. The measured strength variation is in agreement with visually observed tree rings. The acquired data made it possible to determine the mean characteristic points of the tree ring as well as the development of the parameters in dependence on the weather variations.

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DATING OF ROCKFALL EVENTS USING VESSEL LUMEN AREA IN BETULA PENDULA

IAWA Journal ◽

10.1163/22941932-20150100 ◽

2015 ◽

Vol 36 (3) ◽

pp. 286-299 ◽

Cited By ~ 2

Author(s):

Jan Tumajer ◽

Jan Burda ◽

Václav Treml

Keyword(s):

Tree Ring ◽

Tree Rings ◽

Betula Pendula ◽

Callus Tissue ◽

Lumen Area ◽

Event Tree ◽

Strong Reduction ◽

Transport Efficiency ◽

Vessel Lumen ◽

The Mean

Vessel lumen area is influenced by both genetic and environmental forces. Its alterations balance hydraulic water transport efficiency and safety from cavitation or embolism. We tested the hypothesis that environmental stress inflicted by rockfall injury influences average vessel lumen area in newly formed tree rings of Betula pendula Roth, which would make it useful for retrospective detection of rockfall events. We took samples from 11 trees injured by a rockfall that occurred in the winter of 2010–2011, specifically from the stem area adjacent to the injury, parts of the stem located perpendicular to the injury, parts located opposite to the injury, and from four undisturbed trees. We measured the mean vessel lumen area of each tree ring in every sample, comprising up to 10 pre-event tree rings and generally 3 tree rings formed after rock injury. On average, 115 vessels were measured in each tree ring. We then compared the vessel lumen area in tree rings formed after the event with that of rings formed before it as well as with values predicted by an age-trend model inferred from vessel lumen area chronologies. Our results show a strong reduction in vessel lumen area in the first tree ring formed after the event regardless of the position around the stem circumference. This reduction is strongest in wood just next to the callus tissue zone, with decreasing significance in distal parts of the stem circumference. During the three years after the rockfall, the trees mostly recovered their pre-event vessel lumen area, even right next to the place of injury. Still, this value is significantly lower than the value predicted for growth without injury. Abrupt reductions of vessel lumen area turn out to be potentially useful for identifying former rockfall events and can improve on results obtained by traditional methods of dendrogeomorphological dating.

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A Simple Method for the Evaluation of Internal Doses in Nuclear Medicine

Nuklearmedizin ◽

10.1055/s-0038-1624857 ◽

1974 ◽

Vol 13 (02) ◽

pp. 193-206

Author(s):

L. Conte ◽

L. Mombelli ◽

A. Vanoli

Keyword(s):

Nuclear Medicine ◽

Close Agreement ◽

Whole Body ◽

Simple Method ◽

Rapid Estimation ◽

Absorbed Doses ◽

The Mean ◽

The Individual ◽

Estimation Of Risk

SummaryWe have put forward a method to be used in the field of nuclear medicine, for calculating internally absorbed doses in patients. The simplicity and flexibility of this method allow one to make a rapid estimation of risk both to the individual and to the population. In order to calculate the absorbed doses we based our procedure on the concept of the mean absorbed fraction, taking into account anatomical and functional variability which is highly important in the calculation of internal doses in children. With this aim in mind we prepared tables which take into consideration anatomical differences and which permit the calculation of the mean absorbed doses in the whole body, in the organs accumulating radioactivity, in the gonads and in the marrow; all this for those radionuclides most widely used in nuclear medicine. By comparing our results with dose obtained from the use of M.I.R.D.'s method it can be seen that when the errors inherent in these types of calculation are taken into account, the results of both methods are in close agreement.

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SERUM THYROTROPHIN AND THE RESPONSE TO THYROTROPHIN RELEASING HORMONE IN SYMPTOMLESS AUTOIMMUNE THYROIDITIS AND IN BORDERLINE AND OVERT HYPOTHYROIDISM

Acta Endocrinologica ◽

10.1530/acta.0.0750274 ◽

1974 ◽

Vol 75 (2) ◽

pp. 274-285 ◽

Cited By ~ 42

Author(s):

A. Gordin ◽

P. Saarinen ◽

R. Pelkonen ◽

B.-A. Lamberg

Keyword(s):

Autoimmune Thyroiditis ◽

Elevated Serum ◽

Mean Value ◽

Primary Hypothyroidism ◽

Overt Hypothyroidism ◽

Thyrotrophin Releasing Hormone ◽

Releasing Hormone ◽

The Mean ◽

The Individual ◽

Serum Tsh

ABSTRACT Serum thyrotrophin (TSH) was determined by the double-antibody radioimmunoassay in 58 patients with primary hypothyroidism and was found to be elevated in all but 2 patients, one of whom had overt and one clinically borderline hypothyroidism. Six (29%) out of 21 subjects with symptomless autoimmune thyroiditis (SAT) had an elevated serum TSH level. There was little correlation between the severity of the disease and the serum TSH values in individual cases. However, the mean serum TSH value in overt hypothyroidism (93.4 μU/ml) was significantly higher than the mean value both in clinically borderline hypothyroidism (34.4 μU/ml) and in SAT (8.8 μU/ml). The response to the thyrotrophin-releasing hormone (TRH) was increased in all 39 patients with overt or borderline hypothyroidism and in 9 (43 %) of the 21 subjects with SAT. The individual TRH response in these two groups showed a marked overlap, but the mean response was significantly higher in overt (149.5 μU/ml) or clinically borderline hypothyroidism (99.9 μU/ml) than in SAT (35.3 μU/ml). Thus a normal basal TSH level in connection with a normal response to TRH excludes primary hypothyroidism, but nevertheless not all patients with elevated TSH values or increased responses to TRH are clinically hypothyroid.

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Quality of Life for Children with Persistent Sinonasal Symptoms

Otolaryngology ◽

10.1067/mhn.2003.41 ◽

2003 ◽

Vol 128 (1) ◽

pp. 17-26 ◽

Cited By ~ 97

Author(s):

David J. Kay ◽

Richard M. Rosenfeld

Keyword(s):

Quality Of Life ◽

Clinical Care ◽

Longitudinal Change ◽

Good Test ◽

Routine Clinical Care ◽

Before And After ◽

The Mean ◽

The Individual ◽

Sinonasal Symptoms

OBJECTIVE: The goal was to validate the SN-5 survey as a measure of longitudinal change in health-related quality of life (HRQoL) for children with persistent sinonasal symptoms. DESIGN AND SETTING: We conducted a before and after study of 85 children aged 2 to 12 years in a metropolitan pediatric otolaryngology practice. Caregivers completed the SN-5 survey at entry and at least 4 weeks later. The survey included 5 symptom-cluster items covering the domains of sinus infection, nasal obstruction, allergy symptoms, emotional distress, and activity limitations. RESULTS: Good test-retest reliability ( R = 0.70) was obtained for the overall SN-5 score and the individual survey items ( R ≥ 0.58). The mean baseline SN-5 score was 3.8 (SD, 1.0) of a maximum of 7.0, with higher scores indicating poorer HRQoL. All SN-5 items had adequate correlation ( R ≥ 0.36) with external constructs. The mean change in SN-5 score after routine clinical care was 0.88 (SD, 1.19) with an effect size of 0.74 indicating good responsiveness to longitudinal change. The change scores correlated appropriately with changes in related external constructs ( R ≥ 0.42). CONCLUSIONS: The SN-5 is a valid, reliable, and responsive measure of HRQoL for children with persistent sinonasal symptoms, suitable for use in outcomes studies and routine clinical care.

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Tree-Ring Analysis of Intermediate Hawthorn (Crataegus media Bechst.) in NW Poland

Forests ◽

10.3390/f12010029 ◽

2020 ◽

Vol 12 (1) ◽

pp. 29

Author(s):

Anna Cedro ◽

Bernard Cedro

Keyword(s):

Tree Ring ◽

Tree Rings ◽

Agricultural Landscape ◽

Positive Influence ◽

Dominant Factor ◽

Incremental Growth ◽

High Precipitation ◽

Ring Analysis ◽

Uncultivated Land ◽

Nw Poland

Intermediate hawthorn (Crataegus × media Bechst.) is broadly distributed in Europe but very rarely examined by dendrochronologists. In NW Poland, it is one of three naturally occurring hawthorn species, growing mainly at forest margins, along roads, in mid-field woodlots, and on uncultivated land. Biocenotically, it is a very valuable species. This study aimed to determine the age of trees, tree-ring dynamics, and growth–climate relationship for intermediate hawthorn. Signature years were also determined. Samples for analysis were collected from 22 trees growing in a typical agricultural landscape in a monospecific mid-field woodlot comprised of several hundred specimens of various ages and forms (shrubs and trees). Using classic methods of dendrochronological dating, a 40-year long chronology spanning 1981–2020 was constructed. The radial growth rate of intermediate hawthorn is comparable to other tree species forming stands in NW Poland and equals 2.41 mm/year. Considerable intersubject variability is noted, from 1.48 to 4.44 mm/year. The chronology was also used for dendroclimatological analyses, including correlation and response function and signature years. Of the meteorological parameters analyzed, annual incremental growth in hawthorn is the most strongly shaped by precipitation totals from May to August of the current vegetation year: high rainfall favors the formation of wide tree-rings. Statistically significant growth–climate relationships were also obtained for winter months (December of the preceding vegetation year, January and February), for which period negative correlation and regression values are noted for air temperature and insolation. Furthermore, high precipitation, low-temperature and low insolation late in the preceding vegetation year (especially in August) make a positive influence on the condition of trees in the upcoming growing season. Signature year analysis clearly pointed to precipitation as the dominant factor in shaping tree-rings in the studied hawthorn population. As there are no dendrochronological papers concerning indigenous hawthorn species, future studies should be expanded to include diverse geographic locations and habitat conditions and should include all three species of hawthorn occurring in Poland.

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Use and success evaluation of percutaneous aortic balloon valvuloplasty in different hemodynamic entities of severe aortic stenosis in the TAVR era

European Heart Journal ◽

10.1093/ehjci/ehaa946.1934 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

K Piayda ◽

A Wimmer ◽

H Sievert ◽

K Hellhammer ◽

S Afzal ◽

...

Keyword(s):

Heart Failure ◽

Aortic Valve ◽

Aortic Stenosis ◽

Aortic Valve Replacement ◽

Pressure Gradient ◽

Severe Aortic Stenosis ◽

Primary Treatment ◽

Low Flow ◽

Mean Pressure ◽

The Mean

Abstract Background In the era of transcatheter aortic valve replacement (TAVR), there is renewed interest in percutaneous balloon aortic valvuloplasty (BAV), which may qualify as the primary treatment option of choice in special clinical situations. Success of BAV is commonly defined as a significant mean pressure gradient reduction after the procedure. Purpose To evaluate the correlation of the mean pressure gradient reduction and increase in the aortic valve area (AVA) in different flow and gradient patterns of severe aortic stenosis (AS). Methods Consecutive patients from 01/2010 to 03/2018 undergoing BAV were divided into normal-flow high-gradient (NFHG), low-flow low-gradient (LFLG) and paradoxical low-flow low-gradient (pLFLG) AS. Baseline characteristics, hemodynamic and clinical information were collected and compared. Additionally, the clinical pathway of patients (BAV as a stand-alone procedure or BAV as a bridge to aortic valve replacement) was followed-up. Results One-hundred-fifty-six patients were grouped into NFHG (n=68, 43.5%), LFLG (n=68, 43.5%) and pLFLG (n=20, 12.8%) AS. Underlying reasons for BAV and not TAVR/SAVR as the primary treatment option are displayed in Figure 1. Spearman correlation revealed that the mean pressure gradient reduction had a moderate correlation with the increase in the AVA in patients with NFHG AS (r: 0.529, p<0.001) but showed no association in patients with LFLG (r: 0.145, p=0.239) and pLFLG (r: 0.030, p=0.889) AS. Underlying reasons for patients to undergo BAV and not TAVR/SAVR varied between groups, however cardiogenic shock or refractory heart failure (overall 46.8%) were the most common ones. After the procedure, independent of the hemodynamic AS entity, patients showed a functional improvement, represented by substantially lower NYHA class levels (p<0.001), lower NT-pro BNP levels (p=0.003) and a numerical but non-significant improvement in other echocardiographic parameters like the left ventricular ejection fraction (p=0.163) and tricuspid annular plane systolic excursion (TAPSE, p=0.066). An unplanned cardiac re-admission due to heart failure was necessary in 23.7% patients. Less than half of the patients (44.2%) received BAV as a bridge to TAVR/SAVR (median time to bridge 64 days). Survival was significantly increased in patients having BAV as a staged procedure (log-rank p<0.001). Conclusion In daily clinical practice, the mean pressure gradient reduction might be an adequate surrogate of BAV success in patients with NFHG AS but is not suitable for patients with other hemodynamic entities of AS. In those patients, TTE should be directly performed in the catheter laboratory to correctly assess the increase of the AVA. BAV as a staged procedure in selected clinical scenarios increases survival and is a considerable option in all flow states of severe AS. (NCT04053192) Figure 1 Funding Acknowledgement Type of funding source: None

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A Tree Ring Measurement Method Based on Error Correction in Digital Image of Stem Analysis Disk

Forests ◽

10.3390/f12040464 ◽

2021 ◽

Vol 12 (4) ◽

pp. 464

Author(s):

Wenjie Zhang ◽

Tianzhong Zhao ◽

Xiaohui Su ◽

Baoguo Wu ◽

Zhiqiang Min ◽

...

Keyword(s):

Error Correction ◽

Tree Ring ◽

Tree Rings ◽

Digital Image ◽

Regression Equation ◽

Distortion Correction ◽

Geometric Distortion ◽

Stem Analysis ◽

Correction Model ◽

Ring Radius

Stem analysis is an essential aspect in forestry investigation and forest management, as it is a primary method to study the growth law of trees. Stem analysis requires measuring the width and number of tree rings to ensure the accurate measurement, expand applicable tree species, and reduce operation cost. This study explores the use of Open Source Computer Vision Library (Open CV) to measure the ring radius of analytic wood disk digital images, and establish a regression equation of ring radius based on image geometric distortion correction. Here, a digital camera was used to photograph the stem disks’ tree rings to obtain digital images. The images were preprocessed with Open CV to measure the disk’s annual ring radius. The error correction model based on the least-square polynomial fitting method was established for digital image geometric distortion correction. Finally, a regression equation for tree ring radius based on the error correction model was established. Through the above steps, click the intersection point between the radius line and each ring to get the pixel distance from the ring to the pith, then the size of ring radius can be calculated by the regression equation of ring radius. The study’s method was used to measure the digital image of the Chinese fir stem disk and compare it with the actual value. The results showed that the maximum error of this method was 0.15 cm, the average error was 0.04 cm, and the average detection accuracy reached 99.34%, which met the requirements for measuring the tree ring radius by stem disk analysis. This method is simple, accurate, and suitable for coniferous and broad-leaved species, which allows researchers to analyze tree ring radius measurement, and is of great significance for analyzing the tree growth process.

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VARIABILITY OF EVOLUTIONARY RATES OF DNA

Genetics ◽

10.1093/genetics/113.4.1077 ◽

1986 ◽

Vol 113 (4) ◽

pp. 1077-1091

Author(s):

John H Gillespie

Keyword(s):

Dna Sequences ◽

Significant Excess ◽

Ergodic Markov Chain ◽

The Third ◽

Markov Chain Models ◽

Rate Of Molecular Evolution ◽

The Mean ◽

Nuclear Loci ◽

The Individual ◽

Evolution Of Proteins

ABSTRACT A statistical analysis of DNA sequences from four nuclear loci and five mitochondrial loci from different orders of mammals is described. A major aim of the study is to describe the variation in the rate of molecular evolution of proteins and DNA. A measure of rate variability is the statistic R, the ratio of the variance in the number of substitutions to the mean number. For proteins, R is found to be in the range 0.16 < R < 35.55, thus extending in both directions the values seen in previous studies. An analysis of codons shows that there is a highly significant excess of double substitutions in the first and second positions, but not in the second and third or first and third positions. The analysis of the dynamics of nucleotide evolution showed that the ergodic Markov chain models that are the basis of most published formulas for correcting for multiple substitutions are incompatible with the data. A bootstrap procedure was used to show that the evolution of the individual nucleotides, even the third positions, show the same variation in rates as seen in the proteins. It is argued that protein and silent DNA evolution are uncoupled, with the evolution at both levels showing patterns that are better explained by the action of natural selection than by neutrality. This conclusion is based primarily on a comparison of the nuclear and mitochondrial results.

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ABSOLUTE DENDROCHRONOLOGICAL SCALE FOR PINE (PINUS SYLVESTRIS L.) FROM UJŚCIE (NW POLAND), DATED USING RAPID ATMOSPHERIC 14C CHANGES

Radiocarbon ◽

10.1017/rdc.2020.116 ◽

2020 ◽

pp. 1-10

Author(s):

Marek Krąpiec ◽

Andrzej Rakowski ◽

Jacek Pawlyta ◽

Damian Wiktorowski ◽

Monika Bolka

Keyword(s):

High Resolution ◽

Pinus Sylvestris ◽

Middle Ages ◽

Tree Ring ◽

Tree Rings ◽

Matching Method ◽

Early Middle Ages ◽

Rapid Changes ◽

Absolute Age ◽

Nw Poland

ABSTRACT Radiocarbon (14C) analyses are commonly used to determine the absolute age of floating tree-ring chronologies. At best, with the wiggle-matching method, a precision of 10 years could be achieved. For the early Middle Ages, this situation has been markedly improved by the discovery of rapid changes in atmospheric 14C concentrations in tree-rings dated to 774/775 and 993/994 AD. These high-resolution changes can be used to secure other floating tree-ring sequences to within 1-year accuracy. While a number of studies have used the 774 even to secure floating tree-ring sequences, the less abrupt 993 event has not been so well utilized. This study dates a floating pine chronology from Ujście in Wielkopolska (Greater Poland) (NW Poland), which covers the 10th century period and is critical for studies on the beginning of the Polish State to the calendar years 859–1085 AD using the changes in single year radiocarbon around 993/4 AD.

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Evaluation of retinal inflammatory biomarkers after intravitreal steroid implant and Ranibizumab injection in diabetic macular edema

European Journal of Ophthalmology ◽

10.1177/11206721211029465 ◽

2021 ◽

pp. 112067212110294

Author(s):

Ilkay Kilic Muftuoglu ◽

Ecem Onder Tokuc ◽

Fatma Sümer ◽

V Levent Karabas

Keyword(s):

Macular Edema ◽

Diabetic Macular Edema ◽

Outer Nuclear Layer ◽

Plexiform Layer ◽

Retinal Layer ◽

Treatment Naïve ◽

The Mean ◽

The Individual ◽

Inflammatory Component

Purpose: To compare the efficacy of intravitreal (IV) ranibizumab (IVR) injection with IV dexamethasone implant (IVDEX) in treatment naive diabetic macular edema (DME) patients with inflammatory component. Materials and methods: Treatment naive DME eyes with subfoveal neurosensorial detachment (SND) and hyperreflective spots (HRS) were treated either three loading doses of IVR (18 eyes) or one dose of IVDEX (19 eyes). Central macular thickness (CMT), height of SND, the number of HRSs scattered on the individual retinal layers and photoreceptor integrity were assessed using spectral domain- optical coherence tomography scans over 3-months follow-up. Results: The mean change in best-corrected visual acuity (BCVA) was −0.11 ± 0.08 logMAR in IVDEX group and −0.04 ± 0.06 logMAR in IVR group at 1-month ( p = 0.011). IVDEX group showed statistically significant more increase in BCVA compared to those receiving IVR injections at 2-months ( p = 0.004) and 3-months ( p = 0.017) visits. Compared to baseline, the number of total HRSs and the number of HRSs at each individual inner retinal layer significantly decreased in both groups at all follow-up visits. However, IVDEX group showed more decrease in the total number of HRSs at 2- and 3-months ( p < 0.001 at 2-months, and p = 0.006 at 3-months) and in the mean number of HRSs located at inner nuclear layer–outer plexiform layer level ( p = 0.016 at 1-month, p < 0.001 at 2-months, and p < 0.001 at 3-months). After treatment, the number of HRSs on the outer nuclear layer showed some non-significant increase in both groups. Conclusion: HRSs tended to migrate from inner retina to the outer retina in DME eyes by treatment. Dexamethasone seemed to be more effective option in such cases with inflammatory component.

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