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The article discusses the design and operation of a combined unit’s flat disk, which is installed within the unit. The study focuses on the torques caused by forces acting on the unit’s working parts and the conditions for their balancing. The depth at which the flat disk enters the soil and the required diameter to meet this requirement are also presented. The article includes the results of theoretical and experimental studies to determine the shape and area of the disk segment, where the disk’s diameter must be at least 45 cm and the depth of its penetration into the soil is within 14-15 cm.

Aim: To examine the contribution of large-diameter trees to biomass, stand structure, and species richness across forest biomes. Location: Global. Time period: Early 21st century. Major taxa studied: Woody plants. Methods: We examined the contribution of large trees to forest density, richness and biomass using a global network of 48 large (from 2 to 60 ha) forest plots representing 5,601,473 stems across 9,298 species and 210 plant families. This contribution was assessed using three metrics: the largest 1% of trees ≥ 1 cm diameter at breast height (DBH), all trees ≥ 60 cm DBH, and those rank-ordered largest trees that cumulatively comprise 50% of forest biomass. Results: Averaged across these 48 forest plots, the largest 1% of trees ≥ 1 cm DBH comprised 50% of aboveground live biomass, with hectare-scale standard deviation of 26%. Trees ≥ 60 cm DBH comprised 41% of aboveground live tree biomass. The size of the largest trees correlated with total forest biomass (r2 = .62, p < .001). Large-diameter trees in high biomass forests represented far fewer species relative to overall forest richness (r2 = .45, p < .001). Forests with more diverse large-diameter tree communities were comprised of smaller trees (r2 = .33, p < .001). Lower large-diameter richness was associated with large-diameter trees being individuals of more common species (r2 = .17, p = .002). The concentration of biomass in the largest 1% of trees declined with increasing absolute latitude (r2 = .46, p < .001), as did forest density (r2 = .31, p < .001). Forest structural complexity increased with increasing absolute latitude (r2 = .26, p < .001). Main conclusions: Because large-diameter trees constitute roughly half of the mature forest biomass worldwide, their dynamics and sensitivities to environmental change represent potentially large controls on global forest carbon cycling. We recommend managing forests for conservation of existing large-diameter trees or those that can soon reach large diameters as a simple way to conserve and potentially enhance ecosystem services.

Large‐diameter borehole destressing technology is one of the main technical measures for the prevention and control of coal mine rock burst. In engineering practice, there is generally a contradicting problem due to the presence of excess destressing which damages support system and insufficient destressing which results in high stress hardly transfer. In this paper, the mechanism of large‐diameter borehole destressing technology and its influence on anchorage support were simulated and analyzed. Based on this, a segmented enlarged‐diameter borehole destressing technology was proposed. The destressing effect at deep part and anchorage strength changing at shallow part of the coal rib were studied under different borehole parameters. Numerical simulation results show that the destressing effect increases with the increase of the borehole diameter, while borehole with oversize diameter increases the deformation of the roadway and weakens the strength of the anchorage support. The diameter‐enlarging point in segmented enlarged‐diameter borehole destressing technology is best placed between the anchorage end and the vertical stress peak point. The anchorage strength is inversely correlated with the diameter of the small‐diameter section, and the destressing effect is positively correlated with the diameter of the large‐diameter section. Based on its advantages in destressing, the segmented enlarged‐diameter boreholes and anchorage support are applied together, and a system of destressing‐support cooperative control of rock burst is presented. The roles in rock burst control of \"zone of strong anchorage support\" and \"zone of low stress and energy dissipation\" are described. A segmented enlarged‐diameter borehole destressing technology was proposed. The destressing effect at deep part and anchorage strength changing at shallow part of roadway coal side were studied under different borehole parameters.

Forest tree communities are largely structured by interactions between phenotypes and their environments. Functional traits have been popularized as providing key insights into plant functional tradeoffs. Similarly, tree crown—stem diameter and tree height—stem diameter allometric relationships are likely to be strongly coordinated with functional trait tradeoff axes. Specifically, species with functional traits indicative of conservative strategies (i.e., dense wood, heavy seeds) should be related to tree architectures that have lower heights and wider crowns for a given stem diameter. For example, shade‐tolerant species in tropical forests are typically characterized as having dense wood, large seeds, and relatively broad crowns at early ontogenetic stages. Here, we focus on 14 dominant dicot tree species in a tropical forest. We utilized hierarchical Bayesian models to characterize species‐specific height and crown size allometric parameters. We sampled from the posterior distributions for these parameters and correlated them with six functional traits. We also characterize the expected height and crown size for a series of reference stem diameters to quantify the relationship between traits and tree architecture across size classes. We find little interspecific variation in allometric slopes, but clear variation in allometric intercepts. Allometeric height intercepts were negatively correlated with wood density and crown size intercepts were positively related to wood density and seed mass and negatively related to leaf percent phosphorus. Thus, interspecific variation in tree architecture is generated by interspecific variation in allometric intercepts and not slopes. These intercepts could be predicted using a handful of functional traits where conservative traits were indicative of trees that are relatively short and have larger crown sizes. This demonstrates a coordination of tropical tree life histories that can be characterized simultaneously with functional traits and tree allometries. The ontogenetic trajectory of height and crown allocation of tropical trees is an essential indicator of their life histories. Here, we show that this whole plant strategy can be linked to organ‐level plant functional traits leading to insights into how phenotypes are integrated.

The research was conducted with the aim of obtaining equations to estimate the diameter growth of different tree ages for the species (Ziziphus spina-christi) to determine the validity of the site for cultivating the species under study. Field data were collected from the site of the University of Anbar in Anbar Governorate, the city of Ramadi. The samples were randomly selected. Cross sections of the tree were taken. The data were collected by conducting the required field measurements, then the data were tabulated using the Excel program, and by using the method of linear and non-linear regression analysis in the Statgraphics2022 statistical program. Obtaining equations for diagonal growth, precision measures were used to compare between equations (coefficient of determination, standard error, and average absolute error). The equation was reached: d = 0.409131 + 1.90377 * A - 0.384178 * P -0.0443618 * T1 for the diameter growth, where the value of the coefficient of determination was (95.98%), the standard error was (0.084), and the mean absolute error was (0.055).

The accurate estimation of bark thickness is important for foresters for several reasons. It is crucial for timber volume estimation and can help improve the quality of forestry records, and bark has a growing commercial importance as a high-value bioresource. The problem is that models such as the Czech Cubic Tables (CCT) polynomial model are frequently unique. Furthermore, the official method requires rounding down the midspan over-bark diameter (DOB) to the nearest centimetre to estimate the double bark thickness (DBT) and merchantable timber volume. Therefore, we verified the significance of the effects of rounding down the midspan DOB on DBT using a dataset of 438 recently harvested Norway spruce (Picea Abies L. Karst.) logs from the Central Bohemian region. The correlation analysis showed that for measured data without rounding down the diameters, the variability of the DBT was able to explain only 8% of the DOB variability. As for the rounded-down data, the coefficient of determination was slightly higher, reaching 9%. The paired-samples T-tests showed a significant difference between the DBT as calculated directly from measured data and that from the rounded-down over-bark diameters (p < 0.05). The polynomial and linear models underestimated the DBT (2.24 and 1.75 mm on average, respectively) on measured data. In contrast, for data from the rounded-down DOB, the models overestimated the DBT (2.70 or 3.18 mm on average, respectively).

Objective Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) are considered gold standards for measuring visceral fat area (VFA). However, their relatively high prices and potential radiation exposure limit their widespread use in clinical practice and everyday life. Therefore, our study aims to develop a VFA estimated equation based on sagittal abdominal diameter (SAD) and transverse abdominal diameter (TAD) using anthropometric indexes. To the best of our knowledge, there have been limited studies investigating this aspect thus far. Methods This study was designed as a cross-sectional, retrospective cohort survey. A total of 288 patients (167 males and 121 females) aged 18–80 with type 2 diabetes (T2D) were consecutively collected from a multicenter hospital, and VFA was measured by CT. Subsequently, variables highly correlated with VFA were screened through general linear correlation analysis. A stepwise regression analysis was then conducted to develop a VFA estimated equation. Discrepancies between the estimated and actual VFA values were assessed using the Bland-Altman method to validate the accuracy of the equation. Results In the female T2D population, triglyceride (TG), SAD, TAD were found to be independently correlated with VFA; in the male T2D population, BMI, TG, SAD and TAD showed independent correlations with VFA. Among these variables, SAD exhibited the strongest correlation with VFA ( r  = 0.83 for females, r  = 0.88 for males), followed by TAD ( r  = 0.69 for females, r  = 0.79 for males). Based on these findings, a VFA estimated equation was developed for the T2D population: VFA (male) =-364.16 + 15.36*SAD + 0.77*TG + 9.41*TAD − 5.00*BMI (R 2  = 0.75, adjusted R 2  = 0.74); VFA(female)=-170.87 + 9.72*SAD-24.29*(TG^-1) + 3.93*TAD (R 2  = 0.69, adjusted R 2  = 0.68). Both models demonstrated a good fit. The Bland-Altman plot indicated a strong agreement between the actual VFA values and the estimated values, the mean differences were close to 0, and the majority of differences fell within the 95% confidence interval. Conclusions In the T2D population, a VFA estimated equation is developed by incorporating SAD and TAD along with other measurement indices. This equation demonstrates a favorable estimated performance, suggesting to the development of novel and practical VFA estimation models in the future study.

Laparoscopic Roux-en-Y gastric bypass (RYGB) is crucial for significant weight reduction and treating obesity-related issues. However, the impact of gastrojejunostomy (GJ) anastomosis diameter on weight loss remains unclear. We investigate this influence on post-RYGB weight loss outcomes. A systematic search was conducted. Six studies met the inclusion criteria, showing varied GJ diameters and follow-up durations (1–5 years). Smaller GJ diameters generally correlated with greater short-to-medium-term weight loss, with a threshold beyond which complications like stenosis increased. Studies had moderate-to-low bias risk, emphasizing the need for precise GJ area quantification post-operation. This review highlights a negative association between smaller GJ diameters and post-RYGB weight loss, advocating for standardized measurement techniques. Future research should explore intra-operative and AI-driven methods for optimizing GJ diameter determination.

Dendrometer bands have been proposed as an accurate method for measuring tree growth. However, the constrained observation window and the material used in them hamper long-term tree growth monitoring. This study devised a dendrometer band made from stainless steel and primarily extended the extension length of the band spring to yield ample space to monitor diameter increments long-term. A total of more than 500 individual trees, including both coniferous and broadleaf trees, were examined. We compared the dendrometer band’s long-term performance with diameter tape for 5- and 10-year measurements. The results showed that the measurements of the two methods were highly correlated (R > 0.89) in both measuring periods. Differences between the two measurements for individual trees were typically less than 5 mm, and the mean differences at a stand level were less than 2 mm. These consistent observations suggested that the dendrometer band measurements were reliable for long-term measurement. Using the dendrometer bands, we further demonstrated the annual tree growths of diameter at breast height (DBH) and basal area (BA) for ten years of measurements. The size-dependent relationships between DBH/BA growth and initial DBH were also presented. Owing to their simple installation, low cost, and reliable measurement, these dendrometer bands would be helpful in forestry and forest ecology research.

Ground‐based light detection and ranging (LiDAR) is becoming increasingly popular as an alternative means to conventional forest inventory methods. By gauging the distances to multiple points on the surrounding object surfaces, LiDAR acquires 3D point clouds from which tree sizes and spatial distributions can be rapidly estimated. However, the high cost and specialized skills associated with LiDAR technologies have put them out of reach for many potential users. We here introduce ForestScanner, a free, mobile application that allows LiDAR‐based forest inventories by means of iPhone or iPad with a built‐in LiDAR sensor. ForestScanner does not require any manual analysis of 3D point clouds. As the user scans trees with an iPhone/iPad, ForestScanner estimates the stem diameters and spatial coordinates based on real‐time instance segmentation and circle fitting. The users can visualize, check and share the scanning results in situ. By using ForestScanner, we measured the stem diameters and spatial coordinates of 672 trees within a 1 ha plot in 1 hr 39 min with an iPhone and in 1 hr 38 min with an iPad (diameter ≥ 5 cm; detection rate = 100%). The diameters measured by ForestScanner and a diameter tape were in good agreement; R2 = 0.963 for iPhone and R2 = 0.961 for iPad. ForestScanner and a conventional surveying system showed almost identical results for tree mapping (assessed by the spatial distances among trees within 0.04 ha subplots); Mantel R2 = 0.999 for both iPhone and iPad. ForestScanner reduced the person‐hours required for measuring diameters to 25.7%, mapping trees to 9.3%, and doing both to 6.8% of the person‐hours taken using a dimeter tape and the conventional surveying system. Our results indicate that ForestScanner enables cost‐, labour‐ and time‐efficient forest inventories. The application can increase the accessibility to LiDAR for non‐experts (e.g. students, citizen scientists) and enhance resource assessments and biodiversity monitoring in forests world‐wide. 要旨 森林インベントリを行うための新たな手段として、地上LiDARの利用が広がっている。LiDARを使えば、樹木の三次元点群を取得し、そこから幹の直径や空間分布を素早く推定することができる。しかし、LiDARは一般的に価格が高く、扱いに専門技術が必要とされる。そうした点が、潜在的なユーザーにとってLiDARを導入するうえでの障壁となってきた。 本稿では、LiDARセンサーが搭載されたiPhoneやiPadを使って森林インベントリを行うための無料モバイルアプリForestScannerを紹介する。ForestScanner は、ユーザーによる三次元点群の手動処理を一切必要としない。ユーザーはiPhoneやiPadで樹木をスキャンするだけよい。幹直径と空間座標はリアルタイムインスタンスセグメンテーションと円フィッティングによって推定される。測定結果はその場で可視化、確認、共有できる。 ForestScannerを使って、 1 haのプロットに生えている672本の樹木 (幹直径5 cm以上、検出率100%) の幹直径と空間座標を測定した。測定に掛かった時間はiPhoneで1時間39分、iPadで1時間38分だった。ForestScanner および直径巻尺で測った直径の値はよく一致した。 R2値はiPhoneで0.963、 iPadで0.961だった。ForestScanner および従来型測量機器によって得られた樹木の空間座標は、ほぼ同様の結果を示した (0.04 haサブプロット中の樹木間距離によって評価した)。 iPhoneとiPadの両方とも、マンテルR2値は0.999だった。ForestScanner は、直径巻尺および従来型測量機器と比べて、直径、空間座標、および両者の測定に掛かる人工 (にんく) を、それぞれ25.7%、9.3%、6.8%に減少させた。 ForestScannerを使うことで、費用、労働、および時間効率の良い森林インベントリが可能であると示唆された。ForestScannerは、学生や市民科学者にとってLiDARをより身近なものにし、また、世界中の資源評価や生物多様性モニタリングに貢献すると期待される。