Shape Of Neck Research Articles

Determination of Local Cherry Tomato Genotypes' Agromorphological Features in Türkiye and Kyrgyzstan

The purpose of this study was to ascertain some morphological traits and interrelationships of 36 genotypes of cherry tomatoes that were gathered from Turkey and Kyrgyzstan. Measurements and observations include flower number of cluster, leaf length, leaf width, leaf attitude, fruit color, fruit neck shape, fruit cross-sectional shape, fruit weight, fruit firmness, time of maturity, number of locules, thickness of pericarp, and total soluable solid content, in accordance with the guidelines of the International Union for the Protection of New Varieties of Plants (UPOV). The genotypes T40 (62.7 g), T24 (50.8 g), T107 (50 g), T103 (41.4 g), and T105 (40.8 g) had the highest average fruit weights, whereas T3 (9.4 g) and K1 (10.6 g) had the lowest fruit weights. The pericarp had an average thickness of 3.82 mm and an average of 2.49 locules. A spherical fruit cross-section was observed in 97.2% of genotypes. Genotype K2 had the highest total soluble solids content (TTSC%) at 9.4%, whereas genotype K13 had the lowest TTSC% at 3.1%. To measure the data, Principal Component Analysis (PCA) was used. Five separate principle component axes were identified via PCA, and these axes together account for 75.57% of the dataset's variation. These principal components' eigenvalues, which varied from 1.07 to 3.24, showed how much variance was accounted for by each component. The PCA results showed that the genotypes T107, T40, T105, and T87 performed better in PC1 in terms of the number of locules, fruit weight, fruit cross-sectional shape, and pericarp thickness characteristics. Fruit color was influenced by genotypes T90 and T142, fruit firmness by genotype T40, and total soluble solids content by genotype T98. The indigenous cherry tomato varieties from Turkey and Kyrgyzstan were shown to have a large amount of morphological variety, which may be useful for breeding initiatives in the future.

The performance of alternative GPS tracking devices: a case report on wild boars (Sus scrofa)

BackgroundTelemetry studies on terrestrial mammals have been carried out almost exclusively using neck collar-mounted devices. However, collars are not suitable for all species and all age classes and may therefore compromise animal welfare and data quality requirements. Here, we evaluate the use of non-collar tracking devices on wild boars (Sus scrofa), a species for which collars may be problematic due to neck shape and seasonal body mass variation. We tested pelt-glued tags and three types of GPS ear tags. In addition, animals were marked with plain cattle ear tags.ResultsThe tested GPS tags exhibited various technical challenges related mostly to satellite coverage of the study area and tag loss. However, GPS devices enabled moderate movement monitoring of weeks to months, whereas plain cattle ear tags offered information on displacement over longer time intervals. The longest direct dispersal distance (163 km) by a wild boar sounder was discovered by cattle tags.ConclusionsData volume and quality obtained from small tags are inferior to data provided by GPS collars, but low-fix rate tags may enable monitoring of individuals with reduced invasiveness. Moreover, these tags enable tracking in cases where the collar is not an option. The low price and small size of the devices together with technical developments may offer cost-effective tools for future studies on dispersal and survival.

A new autumn-flowering Crocus (Iridaceae) from Türkiye: C. rifatozdemiri sp. nov.

C. rifatozdemiri sp. nov. is a new autumn-blooming species from Crocus series Crocus described from three locations on Mount Çal in Muğla province in southwest Türkiye. The new species is notable for its large showy white flowers with sharply mucronate segment tips and contrasting bright red stigma branches. The exceptionally tall stigma is what most clearly differentiates the new species from its closest relatives, with its long branches that usually divide from above the anther tips, although other morphological features, such as tunic neck and tepal shape, as well as molecular data, support its separation from other members of series Crocus. nrETS and nrITS nuclear regions were used to infer the phylogenetic affiliation of the new species within series Crocus, resulting in a clear separation between it and closest relative C. kofudagensis, as well as other members of the series. Leaf anatomy was found to be similar to other members of series Crocus, which tend to show minimal differences between species. Finally, a full description and diagnosis, chromosome count, line illustration and figures detailing the features of this new endemic taxon, which is so far known only from one mountain in Türkiye.

Deep learning-based automated assessment of canine hip dysplasia

AbstractRadiographic canine hip dysplasia (CHD) diagnosis is crucial for breeding selection and disease management, delaying progression and alleviating the associated pain. Radiography is the primary imaging modality for CHD diagnosis, and visual assessment of radiographic features is sometimes used for accurate diagnosis. Specifically, alterations in femoral neck shape are crucial radiographic signs, with existing literature suggesting that dysplastic hips have a greater femoral neck thickness (FNT). In this study we aimed to develop a three-stage deep learning-based system that can automatically identify and quantify a femoral neck thickness index (FNTi) as a key metric to improve CHD diagnosis. Our system trained a keypoint detection model and a segmentation model to determine landmark and boundary coordinates of the femur and acetabulum, respectively. We then executed a series of mathematical operations to calculate the FNTi. The keypoint detection model achieved a mean absolute error (MAE) of 0.013 during training, while the femur segmentation results achieved a dice score (DS) of 0.978. Our three-stage deep learning-based system achieved an intraclass correlation coefficient of 0.86 (95% confidence interval) and showed no significant differences in paired t-test compared to a specialist (p > 0.05). As far as we know, this is the initial study to thoroughly measure FNTi by applying computer vision and deep learning-based approaches, which can provide reliable support in CHD diagnosis.

Anatomical-Based Customized Cervical Orthosis Design in Automation

Cervical orthoses, vital for neck immobilization in medical care and sports, often struggle to provide adequate support due to individual neck shape and size variations. This study addresses this issue by developing a specific computer-aided orthosis design software tailored for creating customized 3D-printed cervical orthoses. The self-developed software embedded anatomical and rehabilitation knowledge into the orthosis design process, ensuring consistency and reducing manual modification. Finite element analysis of cervical orthoses determined that a minimum thickness of 5 mm PLA (polylactic acid) material is necessary to meet safety requirements. This study highlights the automation potential of customized computer-aided orthosis design and underscores the potential to revolutionize orthopedic care. We also applied easy-to-access 3D printing technology to fabricate well-fitting and immobilized cervical orthoses. These customized cervical orthoses offer a promising future with the advantages of being cost-effective, lightweight, immobility, comfortable, easy to wear, and minimal accessories to meet clinical needs, enhancing patient comfort and compliance and providing reassurance about the economic benefits of the technology.

Collision adhesion law of oil Droplets-Bubbles with different particle sizes in free floating

The treatment of oily wastewater has become a serious problem in the late stage of oilfield development. At the same time, it is of great significance to the improvement of ecological environment. As the key process of oil-bearing wastewater treatment, the study on the binding and adhesion law of oil droplets and bubbles in flotation and its related mechanism can provide reference for its application. Using a double high-speed camera acquisition system, the floating process and collision adhesion law of oil droplets and bubbles in a vertical transparent circular tube were experimentally studied, and the collision adhesion process of oil droplets (0.721 ∼ 3.759 mm) and bubbles (0.797 ∼ 2.886 mm) in different diameters were analysed. It is concluded that the oil droplet and the bubble collide with each other, and then the bubble slides along the surface of the oil droplet, and a neck shape appears at the end of the contact site, and then the neck increases with the diffusion of the oil droplet to form an oil-bubble adhesion body. And the process of elastic drags and contraction separation of the mixture is also demonstrated. It is found that the combination of oil droplets and bubbles with different diameters will have two types of collision adhesion modes, which oil droplet type and oil film type, respectively. Therefore, the diameter ratio of oil droplets and bubbles is a key factor, and when the diameter ratio is greater than 0.75, the adhesion mode of the adhesive body changes from unstable oil droplet type to more stable oil film type.

Laser powder bed fusion sintering mechanism of phenolic resin investigated by ReaxFF molecular dynamics simulations

ABSTRACT This study presents an innovative approach utilising molecular dynamics simulations to elucidate the polymerisation and neck formation mechanisms of phenolic resin during laser powder bed fusion (L-PBF). By developing system and dual-particle models and employing infrared thermal imaging, we established a heat source model for phenolic resin under varying parameters. Our molecular dynamics simulations, using the ReaxFF reactive force field, indicate that high-power lasers significantly enhance cross-linking, achieving a peak polymerisation degree of 78.9% at 30W and 35W power levels. Conversely, increased scanning speed slows product degradation, reducing the polymerisation degree. The interplay of laser power and scanning speed influences polymerisation, with total input energy and heating rate impacting polymerisation and molecular size. Additionally, we investigated neck formation, revealing that small vortices evolve into larger ones during sintering, promoting neck formation. Optical microscopy confirmed diverse neck shapes under different conditions. Quantitative data showed that at a scanning speed of 1000 mm/s, the polymerisation degree reached 93%, with only 2 molecules remaining post-simulation. At 30W power, the largest individual molecule observed was C849H703O117. This research offers crucial insights for selective laser sintering processes, emphasising the importance of high energy input and optimal heating rates for well-formed necks.

The Etiology of Neuromuscular Hip Dysplasia and Implications for Management: A Narrative Review.

This study summarizes the current knowledge of the etiology of hip dysplasia in children with neuromuscular disease and the implications for management. This article is based on a review of development of the hip joint from embryology through childhood growth. This knowledge is then applied to selective case reviews to show how the understanding of these developmental principles can be used to plan specific treatments. The development of the hip joint is controlled by genetic shape determination, but the final adult shape is heavily dependent on the mechanical environment experienced by the hip joint during growth and development. Children with neuromuscular conditions show a high incidence of coxa valga, hip dysplasia, and subluxation. The etiology of hip pathology is influenced by factors including functional status, muscular tone, motor control, child's age, and muscle strength. These factors in combination influence the development of high neck-shaft angle and acetabular dysplasia in many children. The hip joint reaction force (HJRF) direction and magnitude determine the location of the femoral head in the acetabulum, the acetabular development, and the shape of the femoral neck. The full range of motion is required to develop a round femoral head. Persistent abnormal direction and/or magnitude of HJRF related to the muscular tone can lead to a deformed femoral head and a dysplastic acetabulum. Predominating thigh position is the primary cause defining the direction of the HJRF, leading to subluxation in nonambulatory children. The magnitude and direction of the HJRF determine the acetabular shape. The age of the child when these pathomechanics occur acts as a factor increasing the risk of hip subluxation. Understanding the risk factors leading to hip pathology can help to define principles for the management of neurologic hip impairment. The type of neurologic impairment as defined by functional severity assessed by Gross Motor Function Classification System and muscle tone can help to predict the risk of hip joint deformity. A good understanding of the biomechanical mechanisms can be valuable for treatment planning.

Shape of the membrane neck around a hole during plasma membrane repair

Plasma membrane damage and rupture occurs frequently in cells, and holes must be sealed rapidly to ensure homeostasis and cell survival. The membrane repair machinery is known to involve recruitment of curvature-inducing annexin proteins, but the connection between membrane remodeling and hole closure is poorly described. The induction of curvature by repair proteins leads to the possible formation of a membrane neck around the hole as a key intermediate structure before sealing. We formulate a theoretical model of equilibrium neck shapes to examine the potential connection to a repair mechanism. Using variational calculus, the shape equations for the membrane near a hole are formulated and solved numerically. The system is described under a condition of fixed area, and a shooting approach is applied to fulfill the boundary conditions at the free membrane edge. A state diagram of neck shapes is produced describing the variation in neck morphology with respect to the membrane area. Two distinct types of necks are predicted, one with conformations curved beyond π existing at positive excess area, whereas flat neck conformations (curved below π) have negative excess area. The results indicate that in cells, the supply of additional membrane area and a change in edge tension is linked to the formation of narrow and curved necks. Such necks may be susceptible to passive or actively induced membrane fission as a possible mechanism for hole sealing during membrane repair in cells.

Pholiotina sphagnicola sp. nov. (Bolbitiaceae, Agaricales) from Mongolia

A new species Pholiotina sphagnicola sp. nov., was discovered in Mongolia. Its identification was based on phylogenetic analyses of combined nuclear ribosomal DNA internal transcribed spacer region (ITS), nuclear ribosomal DNA 28S subunit (nrLSU), and translation elongation factor 1-alpha (tef1-α), as well as the morphological analyses. The species is characterized by a pileus ranging from hemispherical to convex, with indistinct striae on the margin. The ring is located above the stipe, and the upper sides crenulate-striate. Basidia, which resemble rabbit ears, are 2(1)-spored and have sterigmata ranging from 3 to 13 μm in length. Cheilocystidia are lageniform with a long neck and lanceolate shape; some may exhibit slight swelling at the apex.

Phenotypic performance of Srikayang's shallot variety M1 by colchicine induction

Abstract. Rahmawati ADN, Nandariyah, Parjanto. 2024. Phenotypic performance of Srikayang's shallot variety M1 by colchicine induction. Biodiversitas 25: 1297-1303. Srikayang shallot is one of the shallot varieties from Kulonprogo Yogyakarta, and it has relatively small bulbs. Indonesian consumers prefer shallot, which has dense bulbs, is large (diameter ? 2.5 cm), has a spicy taste, and is fragrant. The efforts to increase shallot's diversity are important. This study aimed to evaluate the performance of Srikayang shallot M1 and evaluate Lethal Doses (LD50) of colchicine. This research was conducted from September to November 2023 at Balecatur Planting Garden, Yogyakarta. Srikayang shallot bulbs were used, and colchicine concentration consisted of 0%, 0.05%, 0.075%, and 0.1%, with a soaking period of 3, 6, and 12 hours. The study was conducted using a randomized block design (RBD). Data were analyzed using descriptive analysis and probit analysis. The colchicine concentration and soaking duration affected the morphological character of Srikayang plants in leaf color, bulb skin color, bulb shape, bulb neck shape, and root tip shape. This study showed that the interaction of colchicine concentration and soaking duration improved variability on plant height, number of leaves, number of saplings, bulb weight in the cluster, main bulb weight, and main bulb diameter. The LD50 of Srikayang shallots was obtained at a colchicine concentration of 0.065%.

Micromechanical prediction of the elastic and plastic properties of sintered steels

One of the characteristic features of sintered steels is the porosity in their microstructure resulting from the compaction and sintering process. This porosity strongly influences the mechanical properties. To enhance the understanding for the structure–property relationship of sintered Astaloy®85Mo with 0.4 wt.%C, a micromechanical modelling approach based on face-centred cubic (fcc) representative volume elements (RVE) is proposed. The fcc-like periodic arrangement of the sintered particles in the RVE enables the consideration of a realistic non-spherical pore morphology. To compare the predictions with experimental results, accompanying uniaxial tensile tests are considered at different pore volume fractions after initial microstructure characterisation. In addition to the effect of pore volume fraction, the influence of sinter necks on the predicted overall strength is also systematically investigated. Despite the fairly simple nature of the underlying fcc structure, the RVE simulations are perfectly capable of reproducing the experimental trend, showing that the elasto-plastic properties decrease with increasing porosity. This is in contrast to analytical predictions, which underestimate the decrease in properties due to spherical pore assumptions. Moreover, the finite element-based simulations reveal a less pronounced influence of the sinter neck shape on the macroscopic behaviour, even though substantial differences in plastic strain localisation are discernible at the microscopic scale.

Effect of pony morphology and hay feeding methods on back and neck postures.

The application of hay feeding devices, such as the use of hay nets or slow feeders, can help with the management of weight in ponies; however, there is still a lack of knowledge regarding their effect on equine posture. Therefore, the aim of the study was to assess the effect of different feeding devices on the posture of ponies using morphometric analysis. Two different breed types, Shetland type (SH, n = 5) versus Welsh Cob type (WC, n = 4), were fed the same forage in four different ways: on the ground (G), using a fully filled haynet (HF), using a partially filled haynet (HL)and using a slow-feeder hay box (HB). Video recordings were obtained and then geometric morphometric analysis was applied. Breed morphology was confirmed by body morphometric measurements. Data were analysed statistically usingone-way ANOVA, canonical variate analysis (CVA), principal component analysis (PCA), partial least-squares (PLS) analysis andmultivariate analysis of variance (MANOVA). Moreover, a mixed model was performed to study differences in mandibular angle. SH and WC ponies were shown to have significantly different body morphometric measurements. The geometric morphometric analysis results showed that ponies arch their back and modify their neck shape differently according to the feeding method and their morphological group. For the neck, the SH and WC ponies adapted similarly to the use of small-holed hay nets, but their posture varied when feeding from the ground or hay box. The back postures consistently differed according to the breed type and feeding method. The mandibular angle for both breed types was reduced with all the feeding devices compared to feeding from the ground. Further studies are needed to evaluate the long-term effects of slow-feeding devices on posture and mandibular angle, taking into consideration animals with different morphologies.

Femoral Neck Thickness Index as an Indicator of Proximal Femur Bone Modeling.

The alteration in the shape of the femoral neck is an important radiographic sign for scoring canine hip dysplasia (CHD). Previous studies have reported that the femoral neck thickness (FNT) is greater in dogs with hip joint dysplasia, becoming progressively thicker with disease severity. The main objective of this work was to describe a femoral neck thickness index (FNTi) to quantify FNT and to study its association with the degree of CHD using the Fédération Cynologique Internationale (FCI) scheme. A total of 53 dogs (106 hips) were randomly selected for this study. Two examiners performed FNTi estimation to study intra- and inter-examiner reliability and agreement. The paired t-test, the Bland-Altman plots, and the intraclass correlation coefficient showed excellent agreement and reliability between the measurements of the two examiners and the examiners' sessions. All joints were scored in five categories by an experienced examiner according to FCI criteria. The results from examiner 1 were compared between FCI categories. Hips that were assigned an FCI grade of A (n = 19), B (n = 23), C (n = 24), D (n = 24), and E (n = 16) had a mean ± standard deviation FNTi of 0.809 ± 0.024, 0.835 ± 0.044, 0.868 ± 0.022, 0.903 ± 0.033, and 0.923 ± 0.068, respectively (ANOVA, p < 0.05). Therefore, these results show that FNTi is a parameter capable of evaluating proximal femur bone modeling and that it has the potential to enrich conventional CHD scoring criteria if incorporated into a computer-aided diagnosis capable of detecting CHD.

Using an Expanded Cervical Flap With an Overlapping Tissue Expansion Technique to Resurface Middle and Lower Facial Defects.

Extensive facial burn scars are a tragedy for patients and often pose a great challenge to surgeons because of the high esthetic and functional demands. For patients with healthy skin in the neck region, a cervical flap is highly recommended for facial resurfacing; however, the skin on the midline of the neck often needs more expansion than that on either side, especially for the treatment of large facial defects. The sufficient longitudinal soft tissue in the anterior neck ensures a normal neck shape as well as a normal range of cervical extension, rotation, and lateral flexion. To overcome this, we developed an expanded cervical flap with an overlapping tissue expansion technique to gain more length centrally. First, 2 tissue expanders were embedded in the anterior neck region overlapping each other at the midline of the neck. After adequate inflation of the expander, the expanded flap was dissected and rotated to repair defects in the middle and lower face. The anchor position of the flap was placed on the horizontal line of the thyroid cartilage to restore the cervicomental angle. Sixteen patients were treated with this method in this single-center study. All defects affected the middle and lower face, with an area ranging from 135 to 185cm 2 , and were caused by a massive facial burn. Among them, 12 patients suffered ectropion of the lower lip, 3 suffered limited mouth opening due to scar contraction, and one patient had a cervicomental adhesion. The area of the expanded flap was approximately 163 to 266cm 2 . The average period of expansion was 89.5 days. Patients were followed up after the operation, with the follow-up period ranging from 6 to 12 months. In all cases, good defect coverage was achieved, with primary closure of the donor sites and a good postoperative cervical configuration. We conclude that the expanded cervical flap with the overlapping tissue expansion technique proved to be a reliable method for facial skin reconstruction with functional and aesthetic improvement.

Abstract 15889: Evaluation of a Novel CTA/DSA-Based Deep-Learning Cerebrovascular Segmentation Method for Cavernous Intracranial Aneurysms

Introduction: CTA is a mainstay diagnostic imaging modality for screening and follow-up of intracranial aneurysms (IAs). One challenge facing neuroradiologists is detection and visualization of IAs on the cavernous internal carotid artery (ICA), which are often obstructed by bony tissue. Such IAs are either missed diagnosed, or must be re-imaged by high-resolution DSA. We sought to evaluate the performance of automated deep learning methods in segmenting cavernous ICA aneurysms from CTA. Methods: In 30 cases, we collected and registered CTA-DSA image pairs to train 2 deep-learning (DL) networks (namely, Brave-Net [BN], and DeepMedic [DM]) for brain vessel segmentation from CTA images of patients with IAs. Segmented DSA was used as the ground truth. Independent testing was performed on a separate cohort of 20 cases to compare network performances. The best-performing network was used for comparison against expert rater assessment in IA detection and segmentation. Quantitative evaluation of expert rater IA segmentation was also performed by comparing IA morphology quantified by parameters, such as size, aspect ratio, neck diameter, and undulation index, against DL predictions. Results: In the independent testing dataset, BN significantly outperformed DM in terms of Dice similarity coefficient DSC (0.875±0.0083 vs. 0.864±0.0075, p=0.004), while DM significantly outperformed BN in terms of precision (0.891±0.016 vs. 0.867±0.017, p&lt;0.001). Qualitative assessment confirmed the superiority of DM in segmenting the IAs located on cavernous ICA. Compared to DM, expert raters missed 7 IAs located on cavernous ICA. Furthermore, DM segmentation provided better measurement of neck diameter (p=0.009), aspect ratio (p=0.029) and shape parameters as compared to the expert rater assessment. Conclusions: A deep learning approach using DM can provide a high-fidelity solution for CTA segmentation of vessels and IAs in the cavernous ICA region.

Ideal Configuration Distribution of Femoral Neck Cannulated Screw in High Altitude Population: A Finite Element Study

For people in high altitude areas, the shape of the femoral neck is different due to the different living environment. To deduce the optimal insertion angle and position of the cannulated screw using three-dimensional finite element technology in patients at high altitude. The data of 100 volunteers were used to establish a finite element model. The stress and displacement of cannulated screws of equilateral and oblique triangle screw placement in femoral neck fracture model and complete femoral neck model were evaluated. On the narrowest plane, the average values of ∠A, B, and C were 47.63o, 75.49o, and 56.88o, respectively, and the shape was an oblique triangle. In complete femoral neck model, the maximum Von Mises stress of the three cannulated screws of equilateral triangle screw placement was slightly larger than oblique triangle screw placement, and this difference was more obvious in femoral neck fracture model. Under same loads, the overall maximum displacement of femur in oblique triangle screw placement was less than equilateral triangle screw placement in two models. For people in high-altitude areas, the three screws should be implanted in an oblique triangle configuration in cannulated screw treatment of femoral neck fractures.

Development of a quantitative analysis method for assessing patient body surface deformation using an optical surface tracking system.

This study aimed to develop a new method to quantitatively analyze body shape changes in patients during radiotherapy without additional radiation exposure using an optical surface tracking system. This method's accuracy was evaluated using a cubic phantom with a known shift. Surface images of three-dimensionally printed phantoms, which simulated the head and neck shapes of real patients before and after treatment, were used to create a deformation surface area histogram. The near-maximum deformation value covering an area of 2 cm2 in the surface image (Def-2cm2) was calculated. A volumetric modulated arc therapy (VMAT) plan was also created on the pre-treatment phantom, and the dose distribution was recalculated on the post-treatment phantom to compare the dose indices. Surface images of four patients were analyzed to evaluate Def-2cm2 and examine whether this method can be used in clinical cases. Experiments with the cubic phantom resulted in a mean deformation error of 0.08mm. With head and neck phantoms, the Def-2cm2 value was 17.5mm, and the dose that covered 95% of the planning target volume in the VMAT plan decreased by 11.7%, indicating that deformation of the body surface may affect the dose distribution. Although analysis of the clinical data showed no clinically relevant deformation in any of the cases, slight skin sagging and respiratory changes in the body surface were observed. The proposed method can quantitatively and accurately evaluate the deformation of a body surface. This method is expected to be used to make decisions regarding modifications to treatment plans.

Mechanism properties of a bird-neck bionic rigid-flexible structure

By the biological construction of a bird neck, a bionic bird-neck multilevel rigid-flexible structure is proposed and some biometric properties are explained. The proposed structure can flexibly deform in six directions, which inspires the study of its mechanical properties for flexible deformations. First, the structural configuration and composition are determined based on the study of the anatomical characteristics of the woodpeckers. Since the skeletons and muscles have very different values for the elasticity modulus and the deformation is mostly dependent on the muscle tension, the bionic structure consists of rigid units and bio-syncretic components. For combined deformations, the mechanical model is established by the connectivity matrix to describe the connection of each level. Second, based on the principle of minimum potential energy, an integral form-finding method is proposed for flexible combination deformations. All of the integral forms obtained with the theoretical analysis are compared with the results with Finite Element Analysis. The structural parameters of the bionic structure were then tightly fixed to the actual shape of the bird's neck and the corresponding overall form took on an "S" shape, which perfectly matched the construction of the bird's neck. In addition, for the pre-deformation form, by analyzing the potential energy of the bionic structure, due to the adjustable dynamic stiffness property, an explanation is provided for the significant dynamic stability of the bird neck in bending. This study not only proposes a bionic rigid-flexible structure with high spatial accessibility but also explains biological properties of a bird neck based on the study of its mechanics characteristics. Based on the modeling and the mechanical properties of the bionic structure in flexible spatial combination deformations, the multi-steady state, and the variable dynamic stiffness, the bird-neck bionic rigid-flexible structure has significant applications such as aeronautical deployable systems, manipulator positioning, and dynamic stability fields.

The key role of levator ani thickness for early urinary continence recovery in patients undergoing robot-assisted radical prostatectomy: A multi-institutional study.

Urinary continence (UC) recovery dramatically affects quality of life after robot-assisted radical prostatectomy (RARP). Membranous urethral length (MUL) has been the most studied anatomical variable associated with UC recovery. To investigate whether levator ani thickness (LAT), assessed with multi-parametric magnetic resonance imaging (mpMRI), correlates with UC recovery after RARP. The study included 209 patients treated with RARP by expert surgeons with extensive robotic experience from 2017 to 2019. All patients had complete, clinical, mpMRI, pathological, and postoperative data including pelvic floor muscle training (PFMT) protocols. After a radiologist-specific training, two urologists independently examined the files, blinded to clinical and pathological findings as well as to postoperative continence status. On mpMRI, LAT, bladder neck (BN) shape, MUL, and apex overlapping (AO) were measured. UC recovery was defined as use of 0 or 1 safety pad at follow-up. Multivariable models were used to assess the association between variables and UC recovery. Overall, 173 (82.8%) patients were continent after a median follow-up of 23 months (interquartile range[IQR]: 17-28). Of these, 98 (46.9%) recovered within 3 months after surgery, 42 (20.1%) from 3 to 6 months, and 33 (15.8%) from 6 months onwards. A significant higher rate of patients with LAT > 10 mm (88.1 vs.75.8%; p = 0.03) experienced UC recovery, compared to those with LAT < 10 mm. This difference was observed in the first 3 months after surgery. At multivariable analysis, LAT (odds ratio [OR]: 1.18, 95% confidence interval [CI]: 1.02-1.37; p = 0.02), Preoperative ICIQ score (OR: 0.91, 95% CI: 0.82-0.98, p = 0.03) and PFMT (OR: 1.98, 95%CI: 1.01-3.93; p = 0.04) independently predict higher UC recovery within 3 months, after accounting for age, BMI, preoperative PSA, D'Amico risk group, MUL, BN shape and AO. LAT greater than 1 cm was associated with greater UC recovery. Specifically, LAT greater than 1 cm seems to be associated with higher UC rate at 3 months after RARP, compared to those with LAT < 1 cm. Magnetic resonance features can help in predicting the risk of incontinence after robot-assisted radical prostatectomy and should be taken into account when counseling patients before surgery.