Perimeter Research Articles

Retinal vascular changes after Silicon Oil removal in the Eye with Rhegmatogenous Retinal detachment

BackgroundThis study aims to examine vessel density changes in the optic nerve and macula following silicone oil removal (SOR) surgery in eyes with rhegmatogenous retinal detachment (RRD) at different time points by Optical Coherence Tomography Angiography (OCTA) in compared to the contralateral eye.MethodsA total of 43 eyes from 43 patients with silicone oil in their eyes for 3–9 months underwent OCT-A using AngioVue and optic disc-associated vessel density (VD) and thickness, macular-associated VD and thickness, Foveal avascular zone (FAZ) area, FAZ perimeter (PERIM), Acircularity index (AI), vessel density within a 300 μm wide region of the FAZ were compared between eyes. OCTA scans were performed one week before SOR and one month and three months after SOR.ResultsThe mean age of participants was 52.8 years (SD = 15.85) and a median visual acuity was 0.8 (range: 0.5-1.0). Notably, male participants constituted 67.4% of the sample. The preoperative mean value BCVA (logMAR) of patients was 0.73, and 3 months post-oil removal was 0.7727. Regarding optic disc parameters, RNFL thickness and vessel density (VD) measurements Peripapillary, whole disc, inside disc, and Disc Angio (superior, Nasal, inferior, temporal) did not change.In analyzing macular thickness parameters, all of them (Whole and Fovea, parafoveal, and Perifovea) remained unchanged. Examining macular vessel density parameters revealed no significant changes across superficial and deep retinal layers. Finally, the comparison of the foveal avascular zone (FAZ) area and flow density (FD) parameters demonstrated consistent measurements with non-significant alterations observed in FAZ size (p = 0.6) and FD values (p = 0.49) over the monitored duration.ConclusionThere was no change in peripapillary VD and macular vessel density of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) after silicone oil removal. FAZ and full retinal thickness remained stable 3 month after SOR. Clinical trial number: Not applicable.

Retreat of the Greenland Ice Sheet leads to divergent patterns of reconfiguration at its freshwater and tidewater margins

Abstract Greenland's marine- and land-terminating glaciers are retreating inland due to climate warming, reconfiguring the way the ice sheet interacts with its proglacial environment. Here we use three decades of satellite imagery to determine whether the ice-sheet margin is becoming more or less exposed to marine and lacustrine processes. During our 1990–2019 study period, we find that the length of ice-sheet perimeter in contact with the ocean shrank by 12.3 ± 3.8% (196.2 ± 10.4 km), due to the retreat of marine-terminating glaciers into narrower fjords. On the other hand, we find that the length of the ice-sheet perimeter in contact with freshwater lakes exhibited more divergent trends that is better explored at regional scales. The length of ice–lake boundaries increased in southwest, north and northwest Greenland but declined in southeast and central east Greenland. The magnitude of change we document during our study period leads us to conclude that the ice sheet is poised for further, substantial reconfiguration in the coming decades with consequences for the flux of fresh water, nutrients and primary productivity in Greenland's terrestrial and oceanic environment.

Light Transfers Through a Koch Shape Cloud

AbstractModeling radiative transfer in a 3D cloudy atmosphere is critical to climate projections. A recently developed fast 3D radiation parameterization scheme gains some success in quantifying horizontal radiative transfer through cloud sides using cloud area fraction. Based on 3D Monte Carlo simulations of radiative transfer through an idealized single‐layer cloud with Koch‐shaped fractal geometry edges, here we show that radiative energy transport through cloud sides correlates more significantly with cloud area fraction than with cloud perimeter length. The results exemplify the importance of accounting for the horizontal radiative energy exchanges between cloud‐free and cloudy regions with cloud area fraction. Results from additional sensitivity simulations show that increased cloud vertical extent often enhances cloud‐side sunlight leak more significantly than cloud‐side sunlight interception. At low sun elevations, cloud‐side sunlight interception is enhanced more than cloud‐side sunlight leak does with the increase of cloud mass.

In Vitro Gene Conservation Status and the Quality of the Genetic Resources of Native Hungarian Sheep Breeds.

Studies revealed a global loss of genetic resources for local sheep breeds. Therefore, the current study aimed to introduce and highlight the progress made on Hungary's existing gene conservation program (small Gene Bank). Furthermore, we evaluated breed (Tsigai, Cikta, and Racka), season, and individual variabilities (n = 24) of the pre-freeze and post-thaw semen stored in the Gene Bank to enhance the gene conservation of the breeds. The samples were cryopreserved manually, and post-thaw spermatozoa were analyzed for motility (CASA), viability, chromatin structure, and morphometry of the sperm nuclei. Ejaculate volume, spermatozoa concentration, subjective motility and standard motility, kinematic parameters, and spermatozoa's head area standard deviation of the post-thaw samples differed significantly among breeds (p < 0.05). Season affected ejaculate volume, total spermatozoa number/ejaculate, STR, BCF, and ALH. We observed a significant (p < 0.001; 0.05) breed and season interaction on concentration, total spermatozoa number/ejaculate, VCL, LIN, WOB, spermatozoa's head average perimeter and nucleus length (Tsigai and Cikta differed but were statistically the same as Racka). Similarly, season significantly (p < 0.05) affected the proportion of ejaculate suitable for freezing. There was a significant (p < 0.05) difference in kinematic parameters and viability among the rams across the breeds. The spermatozoa's head morphometry of the Tsigai and Cikta breeds differed significantly (p < 0.05) among the rams. There were individual and breed differences in many spermatozoa quality parameters. The stored samples are of good quality, with more than 40% having intact membranes and low abnormal chromatin condensation.

The Role of Dental Arch Dimensions and Impacted Third Molars on Mandibular Anterior Segment Crowding.

This study aimed to investigate the potential impact of arch dimensions and unerupted third molars on mandibular anterior segment crowding. This study included a total of 240 subjects with an average age of 18 years seeking orthodontic treatment. Panoramic radiographs, alginate impressions, and study models were taken for measurements. This study utilized the Ganss ratio to calculate the ratio of retromolar space to the width of the crown of the third molar, along with other measurements such as intercanine and intermolar widths, arch perimeter, and arch length to assess dental arch dimensions. We found that the Ganss ratio and angle B values on both the right and left sides were significantly different between the noncrowding and crowding groups, suggesting a potential role for third molars in mandibular anterior segment crowding. Additionally, there was an increase in angle A on both sides in the crowding group, indicating a more acute angle between the anterior teeth. This study also observed a reduction in the retromolar space on the third molars in the crowding group, further supporting the potential role of third molars in mandibular anterior segment crowding. The findings of our study provide substantial evidence to suggest that third molars may contribute to mandibular anterior segment crowding. These findings highlight the importance of carefully evaluating dental arch dimensions and the presence of third molars when assessing and treating mandibular anterior segment crowding.

Effects of slit plate design on mechanical properties of castable plastic bonded explosives

AbstractThe effect of slit plate design on PBXs quality was systematically studied from the point of view voids and powder‐binder separation phenomenon. PBXN‐109 type explosive samples were prepared in accordance with MIL−E‐82886 and cast through slit plates of different geometry and perforation size. The other casting parameters such as casting time, temperature, pressure, valve opening and PBX amount kept constant to prevent uncertainties arising from these parameters. Density measurements, X‐ray inspection and tensile tests were carried out to evaluate the air removal and powder‐binder separation characteristic of slit plates. Density measurements did not provide a clear interpretation of the powder‐binder separation and deaeration abilities of slit plates. X‐ray inspections and tensile tests showed that the dimensions and design of slit plate perforations have impact on voids and powder‐binder separation in PBXs. The slit plate #E showed relatively poor performance in terms of stress property, attributed to the largest cross‐sectional area per perimeter length ratio of perforations, leading to decrease in air removal ability.

A comprehensive analysis of low velocity impact response of [0/±45/90]s thin woven GFRP composites at room temperature

This study is motivated by the need to explore the low-velocity impact behavior of angle-ply thin woven GFRP composites with stacking sequence of [0/±45/90]s, especially the lack of literature concerning damage analysis correlation with a comprehensive range of measurements. The damage diameter, area, and perimeter length are characterized in this study by a novel AutoCAD image processing technique. The test results revealed that specimens subjected to impact energies in the range of 2–30 J are free from edge delamination compared to those tested at 40–50 J. Decreasing the contact duration at impact energy of 60 J is due to perforation accompanied with damage propagation toward the specimen edges and thus, the contact force is sharply dropped from its maximum value of about 4.48kN to 1.3kN. Consequently, both rebound speed and coefficient of restitution dropped to zero. The direct measurement of the energy threshold is increased in the following order: energy threshold at Fmax (2.3–14.9 J), first penetration (load drop) after peak load (23.9–25.6 J), penetration energy threshold (37.9 J), perforation energy threshold (31.1 J), and perforation and crack propagation energies (43.3 J). The perimeter length represents a novel damage parameter, exhibiting a strong correlation with impact energy, as evidenced by a high coefficient of determination of 0.97.

Spontaneous Mandibular Dentoalveolar Changes after Rapid Maxillary Expansion (RME), Slow Maxillary Expansion (SME), and Leaf Expander-A Systematic Review.

This systematic review aims to analyze the spontaneous dentoalveolar changes in the mandibular arch after maxillary expansion in growing patients obtained with different expansion protocols: Rapid Maxillary Expansion (RME), Slow Maxillary Expansion (SME), and Leaf Expander. The study adhered to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Eligibility criteria were established in the PICO format, involving patients who underwent slow, rapid, or leaf maxillary expansion during the mixed or early permanent dentitions. A comprehensive search of electronic databases and manual searches was conducted up to December 2023. The outcome measures included inter-mandibular first permanent molar width, inter-deciduous molar and canine width, arch perimeter, and arch length; both short- and long-term results were considered. The articles that met the inclusion criteria were included in this systematic review and were qualitatively evaluated using a methodological quality scoring system with a 13-point scale. To assess the inter-examiner agreement concerning the article selection and the qualitative assessment of the included studies, Kappa statistics were computed. A total of 1184 articles were identified through electronic and manual searches. After the removal of duplicates and the initial examination of the titles and abstracts, 57 articles were considered for the full text analysis, and according to the eligibility and exclusion criteria, 22 studies were finally selected, composed of 8 randomized controlled trials (RCTs) and 14 retrospective/case-control studies. The qualitative assessment of the included studies showed the following scores: 6 papers have high research quality, 5 have moderate quality, and 11 have low quality. SME demonstrated negligible mandibular changes, with less than 1 mm variation on average (range 0.46-2.00 mm) in the selected parameters and relapses observed in the long term. RME induced more significant increases, particularly in intermolar width greater than 1 mm, which ranged between 0.93 and 3.3 mm, and good stability over the long term. Leaf Expander exhibited promising short-term lower intermolar width increases greater than 1 mm and ranged from 0.5 to 1.69 mm, but long-term stability was not thoroughly evaluated. SME results in negligible short- and long-term effects, while RME, especially with Haas-type appliances, exhibits significant intermolar width increases that remain stable over the years. Leaf Expander shows short-term lower intermolar width increases, requiring further investigation into long-term stability.

Comb size, shape complexity and laterality of laying hens reared in environments varying in resource choice

The comb is an ornament involved in signalling condition in domestic fowl. We hypothesised that comb size, comb shape complexity (i.e., rugosity, the comb perimeter jaggedness), and comb laterality of laying hens would be influenced by the degree of environmental enrichment experienced during juvenile development in the form of resource choice. We conducted a 2 × 2 factorial crossover experiment with pullets reared in pens containing four perches of equal length and four litter areas of equal size. Pullets were exposed to a single choice vs multiple choices of perch and litter types (i.e., all the same vs all different) during Weeks 1–4 (Period 1) and/or Weeks 5–15 (Period 2) of rearing (n = 4 pens/treatment combination) prior to transfer to standard adult laying pens for Weeks 16–27 (Period 3). In Week 27, combs were photographed, and comb laterality (hanging on left or right side) was noted. Using a custom-made image analysis programme, we captured comb area (mm2), perimeter length (mm), and rugosity ((perimeter length – horizontal length) / horizontal length) from comb photographs of 6–7 randomly selected hens/pen. We predicted that hens reared in the multi-choice environment during Periods 1 and 2 would have larger, more complex, and left-side-biased combs than those in the other treatment groups, reflecting lower allostatic load. The predicted comb side bias was based on a possible bias in head posture/movements associated with greater right eye/ear use and left-brain hemispheric dominance. Contrary to our predictions, we detected an overall right-side bias in comb laterality, and no associations between resource choice treatment in Period 1 or Period 2 and comb area, perimeter length, rugosity, or laterality of the adult hens. Thus, variation in allostatic load resulting from the rearing treatments was insufficient to modify the trajectory of comb morphological development, possibly due to a ceiling effect when comparing environmental treatments on the positive end of the welfare spectrum. We found that left-lopping combs had shorter perimeters than right-lopping combs. However, among hens with left-lopping combs, those with larger combs were heavier and had less feather damage, while among hens with right-lopping combs, those with longer-perimeter combs were heavier and tended to have less comb damage. In conclusion, comb characteristics were related to physical condition at the individual level but did not serve as sensitive integrated indicators of hen welfare in response to basic vs enhanced resource choice during rearing.

Pengembangan Kawasan Sentra Bisnis sebagai Kawasan TOD dalam Aspek Berjalan Kaki Kelompok Pekerja

The Golden Triangle Setiabudi represents an economic zone characterised by significant worker mobility. The congestion resulting from this high mobility can be alleviated by implementing the concept of Transit-Oriented Development at existing transit hubs with development potential, namely Setiabudi Astra Station and Bendungan Hilir Station. To implement this concept effectively, understanding the walking preferences of the worker demographic, particularly those aligned with utilitarian walking profiles, is essential. By discerning these preferences, it becomes possible to identify which transit points can cater to the walking requirements of the worker group. This research is executed through qualitative method with data and information obtained through questionnaire and field observations. This investigation revealed that connectivity and pedestrian infrastructure are pivotal factors influencing the walking preferences of the worker group. Both transit hubs also satisfy the criteria for these variables. Hence, it can be inferred that the areas surrounding Setiabudi Astra Station and Bendungan Hilir Station have met the walking preferences of the working demographic and possess the potential to evolve into Transit-Oriented Development zones. However, there is a need to address indicators that remain unmet, notably the block perimeter length, to offer more diverse walking route options for the worker group.

Microstructural Approach Application for Morphological Change Determinations of Grapes during Drying

Grape dehydration is practiced widely in the food industry with large yields of sultanas produced globally. This paper proposes an investigation into the microstructure changes of grapes as they are dried by imaging specimens at intervals during dehydration at two temperatures using scanning electron microscopy. Two main methods were developed to obtain the complex boundaries of cells present in grape tissue in over 36 SEM images. Segmentation of the binary image using an adapted watershed function obtained the most consistent and accurate morphological shape. This was compared to a secondary method which used Canny’s edge detection function, morphological closing and skeletonizing to outline the cellular microstructure. MATLAB was utilised to convert these boundaries into measurable areas so that quantitative data on average cell area, perimeter and cell axis lengths were acquired. It was found that over the drying time, the cell area and perimeter were reduced as expected. Some variability in the data was clear due to only single samples being analysed for each temperature and time combination. Trends in cell perimeter, diameter and shape will be used to demonstrate relationships between morphological structure, drying temperature, and duration. Detailed images of the microstructure were obtained, and a unique image processing algorithm was developed to quantitatively analyse the properties of this microstructure. The development of automatic image processing techniques and algorithms will enable quantitative data to be extracted from any image and extend to any plant/food material.

Axonal stimulation affects the linear summation of single-point perception in three Argus II users.

Objective.Retinal implants use electrical stimulation to elicit perceived flashes of light ('phosphenes'). Single-electrode phosphene shape has been shown to vary systematically with stimulus parameters and the retinal location of the stimulating electrode, due to incidental activation of passing nerve fiber bundles. However, this knowledge has yet to be extended to paired-electrode stimulation.Approach.We retrospectively analyzed 3548 phosphene drawings made by three blind participants implanted with an Argus II Retinal Prosthesis. Phosphene shape (characterized by area, perimeter, major and minor axis length) and number of perceived phosphenes were averaged across trials and correlated with the corresponding single-electrode parameters. In addition, the number of phosphenes was correlated with stimulus amplitude and neuroanatomical parameters: electrode-retina and electrode-fovea distance as well as the electrode-electrode distance to ('between-axon') and along axon bundles ('along-axon'). Statistical analyses were conducted using linear regression and partial correlation analysis.Main results.Simple regression revealed that each paired-electrode shape descriptor could be predicted by the sum of the two corresponding single-electrode shape descriptors (p < .001). Multiple regression revealed that paired-electrode phosphene shape was primarily predicted by stimulus amplitude and electrode-fovea distance (p < .05). Interestingly, the number of elicited phosphenes tended to increase with between-axon distance (p < .05), but not with along-axon distance, in two out of three participants.Significance.The shape of phosphenes elicited by paired-electrode stimulation was well predicted by the shape of their corresponding single-electrode phosphenes, suggesting that two-point perception can be expressed as the linear summation of single-point perception. The impact of the between-axon distance on the perceived number of phosphenes provides further evidence in support of the axon map model for epiretinal stimulation. These findings contribute to the growing literature on phosphene perception and have important implications for the design of future retinal prostheses.

Comparative analysis of optical coherence tomography angiography (OCTA) results between Behçet's disease patients and a healthy control group.

This study aimed to compare optical coherence tomography angiography (OCTA) findings between patients with Behçet's disease (BD) and individuals with healthy eyes. A cross-sectional study. This cross-sectional study was conducted on patients (67 eyes) with BD who were referred to Feiz Hospital and healthy eyes (43 eyes). All subjects underwent Snellenvisualacuity, a slit-lamp examination, measuring intraocular pressure, conducting a dilated fundus examination, OCTA imaging, and spectral-domain (SD)-OCT imaging. OCTA retinal vascular measurements including optic nerve VD, macular-associated VD( superficial and deep), foveal avascular zone (FAZ) area, FAZ perimeter (PERIM), and vessel density within a 300-μm-wide region of the FAZ (FD) were compared between the groups. A significant difference was evident between the two groups (healthy one group and BD group) in terms of parafoveal and perifoveal total retinal thickness, total pRNFL VD in all quadrants except the inferior sector (P < 0.05), and macular superficial, and deep VD in all regions except temporal and superior perifoveal VD (P < 0.05) following adjustments for age, gender, and signal strength index. When comparing the two groups, ocular Behçet's disease (BD) and non-ocular BD, it was evident that peripapillary vessel density (VD) exhibited a significant decrease in ocular BD eyes in all sectors except for the superior and inferior ones, as compared to non-ocular BD eyes. In addition, the comparison of ocular BD and non-ocular BD showed superficial and deep VDs were lower in ocular BD than non-ocular BD in all regions. According to these findings, peripapillary and macular vessel density is affected in BD. Key Points • The study utilized OCTA to compare retinal features in Behçet's disease (BD) patients and healthy individuals, revealing significant differences in retinal thickness and vessel density. • Ocular BD demonstrated reduced peripapillary vessel density compared to non-ocular BD. • The demonstrated association between ADMA and cIMT in patients with early SSc may suggest a role of NO/ADMA pathway in the initiation of macrovascular injury in SSc.

Dental Arch Perimeter and Dimensions in Kurdish Sample Aged 14-25 Years with Class I and Class II Malocclusion

The objectives of this study were to determine and compare the arch perimeter, arch width and vertical arch length in class I normal occlusion and class II malocclusion (division 1 and division 2) in a Kurdish sample of young adults aged 14–25 years. These measurements were taken on 100 study models (50 cases of class I normal occlusion and 50 cases of class II malocclusions). The results showed that (1) Upper and lower arch perimeters of class I normal occlusion were significantly shorter than class II division 1 [at p value= 0.000 , 0.016 ] subsequently ,whereas, no significant difference were found comparing with class II division 2 group[ p value= 0.59 , 0.61] subsequently (2) No differences were found in upper intercanine width in the two different groups of class II malocclusion [p=0.136] and with class I normal occlusion at p&gt; 0.05, (3) upper intermolar width in Class II division 2 were significantly smaller than that in class I normal occlusion [p= 0.000] (4) Lastly, the vertical maxillary arch length in Class II division 1 was significantly larger than Class II division 2 at p&lt;0.05 .

Optical coherence tomography angiography of the foveal avascular zone after successful macula‐off rhegmatogenous retinal detachment repair

Aims/Purpose: To investigate the size and shape of the foveal avascular zone (FAZ) after successful macula‐off rhegmatogenous retinal detachment (RRD) repair using swept source OCT angiography (SS OCTA).Methods: A prospective comparative cross‐sectional study including 21 eyes of 21 patients with macula‐off RRD that were successfully repaired. The size of the superficial FAZ was assessed by its area, length of perimeter, and Feret's diameter, and the shape by the circularity, axial ratio, roundness and solidity. The correlations between each parameter and the clinical and OCT findings were statistically determined. The unaffected fellow eyes were used as controls.Results: The mean initial BCVA was 1.92 ± 0.41 Log MAR (20/2000 Snellen's equivalent). The mean BCVA at OCTA acquisition (3 months) was 0.78 ± 0.39 Log MAR (20/100 Snellen's equivalent) (p &lt; 0.001). FAZ was significantly larger (323.09 ± 129.03 μm2 vs. 245.27 ± 93.15 μm2; p = 0.038), with longer perimeter (2.31 ± 0.35 mm vs. 2.07 ± 0.31 mm; p = 0.048), and irregular shaped (mean circularity: 0.73 ± 0.72 vs. 0.78 ± 0.5; p = 0.019 and mean solidity: 0.90 ± 0.02 vs. 0.93 ± 0.02; p = 0.002) in operated eyes than in the control group. The average Feret's diameter was 0.77 ± 0.10 mm versus 0.71 ± 0.88 mm (p = 0.076). The average axial ratio was 1.25 ± 0.20 versus 1.22 ± 0.22 (p = 0.531), and the average roundness was 0.81 ± 0.11 versus 0.83 ± 0.11 (p = 0.531). Mean central foveal thickness (CFT) was significantly lower in operated eyes than in control eyes (178.23 ± 40.59 μm vs. 247.44 ± 38.2 μm (p &lt; 0.001)). There was a significant inverse correlation between FAZ area and post‐operative outer nuclear layer thickness (r = −0.520, p = 0.016) and CFT (r = −0.571, p = 0.007) in operated eyes. There was no significant correlation between the post‐operative visual acuity and FAZ parameters.Conclusions: Enlargement and irregularities of FAZ after successful macula‐off RRD repair, as demonstrated by SS OCTA, might suggest an ischaemic macular damage caused by RRD that may affect post‐operative functional outcome.

Resistência à punção de lajes lisas com armadura de cisalhamento: considerações sobre os perímetros de controle

Abstract In structural design practice and scientific research on flat slabs, estimating the punching shear resistance of slab-column connection with shear reinforcement involves checking the shear stress acting on a control perimeter outside the shear-reinforced zone. Depending on the arrangement chosen for the shear reinforcement, the design codes` recommendations can lead to different interpretations of the geometry of the external control perimeter, which are, in some cases, also complex to formulate into closed-form equations. Thus, it is common that, especially in hand-made estimates, the slab-column connections are drawn, and dimensions of the external control perimeters are individually measured and applied to the design equations. This paper presents equations developed for ABNT NBR 6118, Eurocode 2 and ACI 318 to account for the length of the control perimeter outside the shear-reinforced zone, allowing the automated calculation for different shear reinforcement arrangements. The different interpretations of the geometry of the external control perimeter of these design codes are discussed and clarified. The proposed equations were validated by comparing their results with those obtained from individual drawing analysis of 62 slab-column connections with varied geometries and shear reinforcement arrangements, and the maximum error was up to 0.1%. This paper significantly contributes to the automation and optimisation of the punching shear strength estimates of slab-column connections with shear reinforcement, clarifying obscure points and automating the definition of the geometry of the external control perimeter.

Predictor Mandibular Dentoalveolar Features on the Occurrence of 1-Rooted/C-Shaped Mandibular Second Molar Teeth.

This study aimed to examine the mandible form features of the mandible, such as inter-second molar width, anteroposterior length, arch perimeter length, arch breadth, corpus height/width in the mandibular second molars (MnSM) region, and arch form, and the relation for the occasion of the 1-rooted/C-shaped. The study analyzed cone-beam computed tomography images of 215 male and 215 female Turkish patients to determine the prevalence of 1-rooted and C-shaped MnSM. Mandibular dentoalveolar characteristics of individuals with bilateral (1R-1R group) and unilateral (1R-2R group) 1-rooted MnSM were examined and compared with those with bilateral 2-roots (2R-2R group) MnSM. Statistical tests were performed using Chi-square, one-way ANOVA, Tukey, and binary logistic regression analysis at the 5% significance level. The prevalence of 1-rooted and 1-rooted/C-shaped MnSM was 12.79% and 9.65%, respectively. Root fusion was more commonly present in females (p<0.05). In the 1R-1R group, the anteroposterior length was shorter than in the 2R-2R group (p<0.05). There was no difference between the groups for other features (p>0.05). Although the study found a shorter anteroposterior length in the 1R-1R group, no feature was a predictive variable for 1-rooted/C-shaped MnSM.

Morphogenetic features of the soil cover structure in the Pritazovsky Arctic (West Siberia)

The aim of the study. To give a morphogenetic characterization of the soil cover structure (SCS) of the Pritazovsky Arctic. Location and time of the study. Soi geography and soil genesis studies were carried out in 2009–2011 in the southern tundra zone of West Siberia on the left-bank part of the Taz River, in its lower reaches. Laboratory work, including analyses, was carried out in 2010–2016. Methods. A large-scale and detailed soil survey was conducted at two key sites with different landscapes. The developed soil maps were digitized in the QGIS package. The obtained digital data about the areas and perimeters of soil areas and soil combinations were converted into MS Excel, where their mathematical processing was done. When classifying soil combinations, the taxonomic system of V.M. Friedland was taken as a basis, as well as the quantitative indicators for the SCS morphogenetic analysis, the indicators also proposed by V.M. Friedland. Results. The basis of the soil cover of the Pritazovsky Arctic consists of Gleysols and Сryosols, which occupy 90,9% of the area. As for the largest areas of these soils, they vary slightly in area and outer perimeter length, having a simple geometric structure. All elementary soil areas (ESA) and soil combinations belong to small and medium-sized areas (&lt;30 ha). More than 90% of the ESA have very small size (&lt;5 ha). The smallest elementary soil areas are occupied by Folic-Сryosols of polygonal roller bogs. Most of the soil areas (83%) of the studied territory have a rounded or elongated shape with slightly curved borders and a short outer perimeter, which determines their monolithic and poorly articulated structure (the coefficient of dissection &lt;2,5). The main differentiating factors of the soil cover are cryogenesis, gley processes, and detritogenesis. In general, the Pritazovsky Arctic soil cover is characterized as monotonously heterogeneous for territories with broken relief and homogeneously monotonous for territories with flat relief. Conclusions. The soil cover of the Pritazovsky Arctic territories with a broken relief is more classificationally contrasting and less geometrically complex compared with the soil cover of the territories with a flat relief. The latter has a very complex geometric structure due to the large number of very small ESA. A mosaic of small soil areas, i.e. the large number of ESA and soil combinations per unit area, strongly distinguishes the tundra soil cover from the soil cover of other bioclimatic zones of West Siberia.

Optical coherence tomography angiography for macular microvessels in ischemic branch retinal vein occlusion treated with conbercept: predictive factors for the prognosis.

To evaluate the predicative factors of visual prognosis using optical coherence tomography angiography (OCTA) in ischemic branch retinal vein occlusion (BRVO) patients with macular edema (ME) after anti-vascular endothelial growth factor (VEGF) treatment. In this retrospective analysis, data from 60 patients (60 eyes) with a definite diagnosis of ischemic BRVO with ME by fundus fluorescein angiography (FFA) were studied. The eyes with ME according to spectral domain optical coherence tomography (SD-OCT) underwent intravitreal conbercept (IVC) and 3+pro re nata (PRN) regimen. The injection times were recorded. Two weeks after injection, fundus laser photocoagulation was performed in the non-perfusion area of the retina. The patients were followed up once a month for 6mo. The best-corrected visual acuity (BCVA), foveal avascular zone (FAZ), and A-circularity index (AI), at 6mo and the baseline were compared. All patients showed significant improvement in BCVA from 0.82±0.32 to 0.39±0.11 logMAR (P<0.001). The mean central macular thickness (CMT) significantly decreased from 476.22±163.54 to 298.66±109.23 µm. Both the FAZ area and AI at 6mo were significantly higher than those at the baseline: the FAZ area increased (0.38±0.02 vs 0.39±0.02 mm2, P<0.05); the AI increased (1.27±0.02 vs 1.31±0.01, P=0.000). The baseline BCVA showed a significantly positive correlation with the baseline FAZ area, FAZ perimeter (PERIM) and AI, final visual gain (FVG) and injection times, respectively (P<0.001). FVG showed a significantly negative correlation with the FAZ area, PERIM, AI and injection times, but a significantly positive correlation with vessel densities (VDs) 300 µm area around FAZ (FD-300; P<0.001). Injection times was positively correlated with the baseline FAZ area, and AI, but inversely correlated with the baseline FD-300 (P<0.001). However macular ischemia was noted in 5 cases during follow-up. Using OCTA to observe macular ischemia and quantify parameters can better predict the final visual prognosis of patients before treatment. The changes in FAZ parameters may influence the visual prognosis and injection times.

The effect of plant size on the phytoliths characteristics of short cells in the leaf epidermis of Dactylis glomerata L.

The present study is devoted to the revision of the influence of plant organs size on the size of phytoliths. Phytolith size parameters are used to identify cultivated grasses species in archaeological sites. Understanding how these characteristics are variable is necessary in such studies. The study of the variability of the phytoliths morphometric parameters will increase the possibilities of their use in plant systematics. The article presents a correlation analysis between the average values of the morphometric characteristics of Dactylis glomerata phytoliths from six different habitats with leaf sizes and generative shoots. The cock’s-foot specimens from forest, meadow and anthropogenically disturbed plant communities in the mountainous and plain parts of the south of Western Siberia were studied. Extraction of phytoliths was carried out using dry ashing. The measurement was made using the ImageJ software. Past 4.03 programs was used for statistical processing. The influence of the leaf length on the average values of the parameters of width, equivalent diameter, and inscribed radius of phytoliths of short epidermal cells of leaf was revealed. With an increase in the size of the leaf, the width of the phytolith and the parameters associated with it increase. The length of phytoliths, their area, perimeter, area and perimeter of the described figures weakly depend on the size of the vegetative organs of plants.&#x0D; Key words. Crenate, Dactylis glomerata, morphometry, phytoliths, short cells.