Transverse Dimensions Research Articles

Cardiovascular crossroads - exploring the impact of atrial fibrillation on mitral valve regurgitation and MitraClip treatment

Abstract Introduction The use of the MitraClip technique is becoming increasingly popular as a treatment option for patients suffering from mitral valve regurgitation who are not suitable for surgery. It is unclear how pre-existing atrial fibrillation impacts patients during the procedure. Purpose The question arises: What is the underlying cause of atrial fibrillation in patients with significant mitral valve involvement and why do some patients remain unaffected? This study aims to compare and identify differences in cohorts of patients with and without atrial fibrillation before the MitraClip procedure. Methods We analyzed a register of 279 patients who underwent MitraClip treatment. The study classified the patients according to the presence (n=140, 50%) or absence (n=139, 50%) of atrial fibrillation prior to the procedure. We utilized univariate analysis to compare demographic, clinical, and echocardiographic parameters. Multivariate logistic regression was also performed to determine significant predictors. Results Both cohorts were of similar size, but there were significant differences in certain parameters. Women were more frequent in the group without atrial fibrillation (45% compared to 34%, p=0.045). The group with atrial fibrillation was slightly older (73 years compared to 70 years, p<0.001) and had a lager body surface area (1.95 compared to 1.87, p=0.005). Parameters such as Euroscore II, NT-proBNP and creatinine levels were not significantly different. Nevertheless, it is important to note that the group with atrial fibrillation had a greater transverse dimension of the left atrium (55 compared to 50, p<0.001). Additionally, the atrial fibrillation group exhibited a higher degree of tricuspid regurgitation (2.9 vs 2.0, p=0.007) and a slightly lower baseline VO2 max (11.63 vs 12.59, p<0.001). Multivariate logistic regression revealed that baseline tricuspid regurgitation is a significant predictor of atrial fibrillation, with and odds ratio of 2.066 (95% CI: 1.041-4.097, p=0.038). Conclusion During the MitraClip procedure, patients with atrial fibrillation demonstrate certain specific characteristics, including older age, increased body surface area, larger left atrial size, and higher grade of tricuspid regurgitation. The significant association of tricuspid regurgitation with atrial fibrillation emphasizes its potential role in clinical evaluation and subsequent treatment.

Analysis of peculiarities of polymer matrix microstructure in PCMs formed under the influence of electrophysical effects

The microstructure of monolayer samples formed by 3D printing from composite prepregs reinforced with continuous carbon fiber, followed by treatment in a cured state by exposure to ultrasonic vibrations and a microwave electromagnetic field, has been studied. It has been shown that high-power ultrasonic exposure causes macro-changes, which are characterized by a decrease in the number and transverse dimensions of delaminations (cracks) from 0.05–0.1 mm to 0.01–0.02 mm and a decrease in the height of microrelief elements by almost an order of magnitude. Changes caused by exposure to a microwave electromagnetic field are more apparent when examining the end surface with an increase from ×1000 to ×10000. The control samples revealed fibers consolidated by binder in combination with unfilled gaps in a ratio of about 50:50, with individual globular fragments of frozen binder on their surface. The samples after microwave exposure revealed the presence of large areas without defects, completely uniformly filled with binder, fibers from all sides are in contact with the binder, in which there are voids no larger than 5 × 1.5μm in size. Greater orderliness of the structure of monolayers is most typical for samples with two-stage processing, including preliminary ultrasonic and subsequent.

Modern innovations in the provision and efficient application of 2D inorganic nanoscale materials

Abstract Two-dimensional nanoscale materials (2D NMs) have exceptional physical characteristics, distinctive structures, and customizable surface chemistry. They consist of infinite transverse dimensions of near-atomic thickness or atoms. They promise advancements in catalysis, renewable energy, and sensing. An extensive summary of the most recent research results on the creation and use of 2D NMs is provided in this work. It is possible to modify the characteristics of these multi-layered materials by means of chemical and physical manipulations. Due to their layer-dependent electrical properties, certain 2D layered inorganic nanomaterials such as MoS2, WS2, and SnS2 have recently been created and used in a variety of applications, including new sensors. In addition, the article delves into the difficulties confronted by sectors reliant on nanotechnology as well as the potential future uses of nanostructures coupled with electrochemical systems. The article begins by outlining the typical “top-down” and “bottom-up” approaches for synthesizing 2D NMs. These approaches include hydrothermal procedures, ion intercalation, mechanical exfoliation, liquid-phase exfoliation assisted by ultrasonic waves, and chemical vapor deposition. 2D NMs are the focus of this work because of their potential applications in gas sensing, photocatalysis, electrocatalysis, photo detection, and electromagnetic wave absorption. In addition, the study predicts patterns of future development and possible issues with 2D NMs based on existing studies. Increased demand for cost-effective, environmentally friendly, and highly connected products is propelling the ongoing research and development of these high-performance materials. This research is significant since it summarizes, in one place, the most recent advances in 2D NM preparation methods and applications.

Evaluation of a Fully Digital, In-House Virtual Surgical Planning Workflow for Bimaxillary Orthognathic Surgery

The advantages of virtual surgical planning (VSP) for orthognathic surgery are clear. Previous studies have evaluated in-house VSP; however, few fully digital, in-house protocols for orthognathic surgery have been studied. The purpose of this study was to evaluate the difference between the virtual surgical plan and actual surgical outcome for orthognathic surgery using a fully digital, in-house VSP workflow. This is a prospective cohort study from September 2020 to November 2022 of patients at the Victoria General Hospital in Halifax, NS, Canada who underwent bimaxillary orthognathic surgery. Patients were excluded if they had previously undergone orthognathic surgery or were diagnosed with a craniofacial syndrome. The primary outcome variables were the mean 3-dimensional (3D) (Euclidean) distance error, as well as mean error and mean absolute error in the transverse (x axis), vertical (y axis), and anterior-posterior (z axis) dimensions. Covariates included age, sex, and surgical sequence (mandible-first or maxilla-first). The primary outcome was tested using Z and t critical value confidence intervals. The P value was set at .05. The 3D distance error for mandible-first and maxilla-first groups was compared using a 2-sample t-test as well as analysis of variance. The study sample included 52 subjects (24 males and 28 females) with a mean age of 27.7 (± 12.1) years. Forty three subjects underwent mandible-first surgery and 9 maxilla-first surgery. The mean absolute distance error was largest in the anterior-posterior dimension for all landmarks (except posterior nasal spine, left condyle, and gonion) and exceeded the threshold for clinical acceptability (2mm) in 16 of 23 landmarks. Additionally, mean distance error in the anterior-posterior dimension was negative for all landmarks, indicating deficient movement in that direction. The effect of surgical sequence on 3D distance error was not statistically significant (P=.37). In general, the largest contributor to mean 3D distance error was deficient movement in the anterior-posterior direction. Otherwise, mean absolute distance error in the vertical and transverse dimensions was clinically acceptable (< 2mm). These findings were felt to be valuable for treatment planning purposes when using a fully digital, in-house VSP workflow.

Three-dimensional Spinal Canal Morphometric Analysis and Relevant Spinal Cord Occupational Ratios in Congenital Cervical Spinal Stenosis: A Classification Algorithm of the Stenosis Phenotypes and Data-driven Decompression Approach

No standardized magnetic resonance imaging (MRI) parameters have defined the 3-dimensional morphoanatomy and relevant spinal cord occupation ratios (occupation of spinal cord dimensions/similar dimensions within the spinal canal) in congenital cervical stenosis (CCS). A retrospective, comparative analysis was conducted on 200 patients >18 years of age with myelopathy and CCS (mean age, 52.4 years) and 200 age-matched controls with no myelopathy or radiculopathy. The variables assessed from high resolution MRI included sagittal and axial spinal canal dimensions (MRI Torg-Pavlov ratios) from C3 to C7. Morphometric dimensions from the sagittal retrodiscal and retrovertebral regions as well as axial MRI dimensions were compared. Sagittal and axial spinal cord occupation ratios were defined and correlated with spinal canal dimensions. Multivariate analyses indicated reduced sagittal and axial anteroposterior (AP) spinal canal dimensions and a large reduction in transverse spinal canal dimensions at all spinal levels. There was a small significant correlation between AP sagittal spinal canal dimensions and axial transverse spinal canal dimensions at C3-C5, but not at C5-C6. Small correlations were noted between AP sagittal spinal canal dimensions and AP axial spinal cord and axial cross-sectional area occupation ratios at C3-C6, but there was no correlation with axial mediolateral spinal cord occupation ratios. The stenosis effect can involve any dimension, including the transverse spinal canal dimension, independent of other dimensions. Owing to the varied observed morphoanatomies, a classification algorithm that defines CCS specific phenotypes was formulated. Objectivizing the stenosis morphoanatomy may allow for data-driven patient-focused decompression approaches in the future.

Low profile cavity-embedded ultra-wideband UHF array antenna with end-fire beams

A low profile, vertically polarized, ultra-wideband array antenna with end-fire beams operating in an ultra-high frequency (UHF) band is developed in this paper. The array antenna consists of 1×16 log-periodic top-hat loaded monopole antenna arrays and is feasible to embed into a shallow cavity to further reduce the array height. Capacitance is introduced in the proposed antenna element to reduce profile height and the rectangular top hats are carefully designed to minimize the transverse dimension. Simulated results show that when the antenna array operates in a frequency range of 300 MHz–900 ​MHz, the end-fire radiation pattern achieves ±45° scanning range in the horizontal plane. Then prototypes of the proposed end-fire antenna element and a uniformly spaced linear array (1×2) are fabricated and validated. The end-fire antenna array should be suitable for airborne applications where low profile and conformal scanning phased antenna arrays with end-fire radiations are required. This design is attractive for airborne platform applications that are used to search, discover, identify, and scout the aerial target with vertically polarized beams.

CRANIOMETRICAL CHARACTERISTICS OF THE HUMAN FETAL SKULL

The purpose of the study – to ascertain the regularities of the age-related dynamics ofmorphometric changes of the skull in the fetal period of human ontogenesis.Material and methods. 59 specimens and 12 computed tomography (CT) scans of theskulls of human fetuses aged from 4 to 10 months of intrauterine development (IUD)were studied. A complex of morphological research methods was applied, which includedanthropometry, morphometry, three- dimensional reconstruction and statistical analysis.The results. It has been established that the longitudinal and transverse dimensions, thecircumference of the cerebral part of the skull grow almost uniformly before birth, but bythe 5th month of the IUD, a more accelerated growth is observed, due to which the scatterdiagram has the appearance of a logarithmic dependence. A somewhat uneven growth ofthese morphometric indicators is also observed in the age-related changes in the width andupper height of the face. The growth of the facial angle during the fetal period was revealed,which can be explained by the development of the mandible («pushing» it forward). At the same time, the basilar angle slightly decreases during the fetal period of development,which can be explained by the increase in the brain volume. The basilar angle increaseswith the age of the fetus, but somewhat unevenly in leptins, i. e., until the beginning of the6th month, it almost does not change, during the 6th-7th months it increases intensively,and then slows down again until the end of the fetal period of IUD. In euryons, there isa uniform growth of the basilar angle throughout the fruiting period of development, andmore intensively than in the average morphotype – mesens. Analysis of the correlation offetal age, cranial index, and basilar angle size showed even more significant anatomicalvariability. Thus, if in dolicho- and mesomorphs the basilar angle grows almost uniformlyduring the fetal period, then in brachymorphs it first intensively decreases until the 6thmonth of development, and then begins to grow until the newborn period. It should be notedthat a similar feature is observed in the dynamics of age-related changes in the facial angle,in addition to slowing down its growth from the 8th month in dolichomorphs.Conclusions. 1. Regression analysis of the correlation of age, morphotype indicators, andbasilar and facial angles made it possible to establish patterns of individual morphometricvariability of the skull in the dynamics of the fetal period of prenatal human development,as well as to identify critical periods of morphogenesis of the brain and facial parts ofthe skull, which are 6-7 months in leptins, the 6th month – for brachymorphs and the 8thmonth – for dolichomorphs. 2. The size of the basilar angle of the skull is an importantdiagnostic and prognostic indicator in combination with indices that characterize themorphotype of the individual, for monitoring the normal development of the skull andbrain of the fetus.

Osteomodulin deficiency in mice causes a specific reduction of transversal cortical bone size.

Skeletal growth, modeling, and remodeling are regulated by various molecules, one of them being the recently identified osteoanabolic factor WNT1. We have previously reported that WNT1 transcriptionally activates the expression of Omd, encoding Osteomodulin (OMD), in a murine mesenchymal cell line, which potentially explained the skeletal fragility of mice with mutational WNT1 inactivation, since OMD has been shown to regulate type I collagen fibril formation in vitro. In this study we confirmed the strong induction of Omd expression in a genome-wide expression analysis of transfected cells, and we obtained further evidence for Omd being a direct target gene of WNT1. To assess the in vivo relevance of this regulation, we crossed Omd-deficient mice with a mouse line harboring an inducible, osteoblast-specific Wnt1 transgene. After induction of Wnt1 expression for 1 or 3weeks, the osteoanabolic potency of WNT1 was not impaired despite the Omd deficiency. Since current knowledge regarding the in vivo physiological function of OMD is limited, we next focused on skeletal phenotyping of wild-type and Omd-deficient littermates, in the absence of a Wnt1 transgene. Here we did not observe an impact of Omd deficiency on trabecular bone parameters by histomorphometry and μCT either. Importantly, however, male and female Omd-deficient mice at the ages of 12 and 24weeks displayed a slender bone phenotype with significantly smaller long bones in the transversal dimension, while the longitudinal bone growth remained unaffected. Although mechanical testing revealed no significant changes explained by impaired bone material properties, atomic force microscopy of the femoral bone surface of Omd-deficient mice revealed moderate changes at the nanostructural level, indicating altered regulation of collagen fibril formation and aggregation. Taken together, our data demonstrate that, although OMD is dispensable for the osteoanabolic effect of WNT1, its deficiency in mice specifically modulates transversal cortical bone morphology.

Mechanical property measurement at high temperature based on a new disc-shaped specimen

Three-dimensional digital image correlation (3D-DIC) is frequently used to measure mechanical properties of materials. However, the traditional dumbbell-shapedspecimen has some limitations for measurment of mechanical properties of materials by use of 3D-DIC at high temperature due to two reasons: (1) its transverse dimension is very small and only a small number of valid speckles can be used in 3D-DIC; and (2) only a small amount of valid information, such as the average deformation of the gauge length, can be used to obtain mechanical properties in one direction. In this work, a new test method based on a disc-shaped standard specimen is first proposed. By use of analytical solutions of a disc under a uniform radial load, and measured results of the full-field displacement of the disc-shaped specimen by 3D-DIC in an effective test region at different high temperatures, mechanical properties at different high temperatures are identified.

Longitudinal cardiac dimensions in patients undergoing LVAD implantation.

In conventional left ventricular assist devices (LVAD), a separate outflow graft is sutured to the ascending aorta. Novel device designs may include a transventricular outflow cannula crossing the aortic valve (AV). While transversal ventricular dimensions are well investigated in patients with severe heart failure, little is known about the longitudinal dimensions. These dimensions are, however, particularly critical for the design and development of mechanical circulatory support (MCS) devices with transaortic outflow cannula. In an explorative retrospective cohort study at the University Medical Center Freiburg, Germany, the longitudinal cardiac dimensions of patients undergoing computed tomography angiography (CTA) before and, if available, after LVAD implantation were analyzed. Among others, the following dimensions were assessed: (a) apex to AV, (b) apex to mitral valve, (c) AV to sinotubular junction (STJ), (d) apex to STJ, (e) apex to brachiocephalic artery (BCA), and (f) AV to BCA. In total, 44 LVAD patients (36 male, age 55.8 years, height 1.75 m) were included. The longitudinal cardiac dimensions were (a) 114.5 ± 12.1 mm, (b) 108.0 ± 12.4 mm, (c) 20.9 ± 2.9, (d) 135.4 ± 13.4 mm, (e) 206.0 ± 18.3, and (f) 91.5 ± 9.8 mm. Postoperatively, (a) and (b) decreased by 31.5% and 39.5%, respectively (N = 14). Longitudinal cardiac dimensions may be reduced by up to 40% after LVAD implantation. A better knowledge of these dimensions and their postoperative alterations in LVAD patients may improve surgical planning and help to design MCS devices with transventricular outflow cannula.

‘I like exploring other languages’: primary and lower secondary students’ attitudes towards plurilingual education

ABSTRACT While teachers’ beliefs about plurilingual education are widely studied, there is a gap in research exploring learners’ orientations. Drawing on a conceptualisation of plurilingual education distinguishing between three pluralistic approaches to languages and a transversal dimension focusing on learners’ language resources, the article investigates primary and lower secondary students’ attitudes towards plurilingual education in response to plurilingual education being implemented in the students’ language teaching. Based on interview data collected in a multiple-case study from majority and minority language students in Grades 1, 5 and 7, the analysis displays consistent learner positivity towards plurilingual education, especially emphasising the éveil aux langues approach whereas the integrated didactic approach as well as intercomprehension between related languages receive less attention. The findings indicate that the attitudes towards plurilingual education are linked to the learners’ language resources creating a framework for the students’ encounters and comparisons with other languages. Combining the findings and research literature on plurilingualism as a universal criterion for all learners in a modern, globalised world, the article suggests a continuum of the learner's plurilingualism. However, the findings reveal that experienced plurilingual education contexts do not only foster positive attitudes towards linguistic diversity, but that discriminating language-hierarchising attitudes co-exist.

Dominance of polarization modes and absorption on self-focusing of laser beams in collisionless magnetized plasma

This work investigates the polarization modes i.e., Extraordinary (E-mode) and Ordinary (O-mode) on self-focusing of higher-order mode of elegant Hermite-cosh-Gaussian (EHChG) laser beams within collisionless magnetized plasma medium. In this study, the authors have taken transverse electromagnetic ([Formula: see text]) mode with mode indices (0, 4) and explored. The ponderomotive force is primarily responsible for the dielectric constant’s nonlinearity in this context. Also, WKB and paraxial approximations via the parabolic wave equation approach are used to establish the general form of differential equations for beam-width parameters in both transverse dimensions of the beam. In this paper, the authors have theoretically investigated the dominance of polarization modes and absorption coefficient on self-focusing. The final results show good enhancement of laser propagation through collisionless plasma medium.

Fracture propagation morphology and parameter optimization design of pre-CO2 hybrid fracturing in shale oil reservoirs, Ordos Basin

Shale reservoirs typically exhibit the characteristics of large burial depth, low permeability, and well-developed bedding. Despite the implementation of water-based fracturing techniques with high displacement, attaining the optimal reservoir stimulation effect remains a formidable challenge. Consequently, in recent years, a novel method of hybrid fracturing method using pre-CO2 + sand-carrying slick water has been proposed. Within this framework, the meticulous design of fracturing operation parameters stands out as a pivotal factor influencing the efficacy of reservoir stimulation. This paper presents a coupled 3-D hydraulic fracture propagation model, investigating the influence of injection displacement, injection volume, and three-stage pre-injection fluid volume ratio on the fracture propagation. Two quantitative evaluation metrics, namely fracture surface area S and fracture transverse plane fractal dimension D, are precisely defined. Additionally, real-time analysis of bottom-hole pressure is conducted to further comprehend the dynamics of the process. Numerical investigations have revealed that both pre-CO2 injection displacement and volume exert a substantial influence on fracture half-length and complexity. Furthermore, the proportion of hybrid fracturing fluid demonstrates a notable impact on fracture height and complexity. The design of injection parameters does not exhibit a significant effect on the formation breakdown pressure. This study quantitatively evaluates fracture propagation under different working conditions from the perspective of fracture morphology, and serve as practical guidance for optimizing the process parameters design for hybrid fracturing in shale oil reservoirs, Ordos Basin.

Accuracy of orthodontic movements with 3D printed aligners: A prospective observational pilot study.

Owing to the availability of 3D software, scanners, and printers, clinicians are encouraged to produce in-office aligners. Recently, a new directprinting resin (Tera Harz TC-85DAC) has been introduced. Studies on its mechanical characteristics and biological effects have been published; however, evidence on its efficacy in orthodontic treatment remains scarce. This pilot study aimed to investigate the accuracy of teeth movement achieved with directprinted aligners. Seventeen patients (eight males and nine females) with a mean age of 27.67 ± 8.95 years, presenting with dental rotations < 30° and spaces/crowding < 5 mm, were recruited for this study. The teeth movement was planned starting from a T0 digital dental cast. The 3D direct-printed aligners were produced using Tera Harz TC-85DAC resin. Once the orthodontic treatment was completed, a final digital cast was obtained (T1). The planned teeth positions were then superimposed onto the T0 and T1 digital models. The differences between the programmed movements and the achieved overall torque, tip, rotation, and transverse dimensions were assessed using the paired t test or Wilcoxon's signed rank test. The overall accuracies for torque, tip, and rotation were 67.6%, 64.2%, and 72.0%, respectively. The accuracy of the change in transverse diameter was 99.6%. Within the limits of the present pilot study (difficulties with abnormally shaped teeth and use of attachments), it can be concluded that 3D printed aligners can be successfully printed in-house and utilized for mildly crowded cases, with a comparable accuracy of tooth movement to that of other aligners.

Tooth-Bone-Borne vs Bone-Borne Rapid Maxillary Expanders on Dentoskeletal Changes.

This study compared the insertion and thickness of the cortical bone, the parallelism of the midpalatal suture, and the skeletal transverse dimension using a microimplant-assisted rapid palatal expansion (MARPE) with those produced by bone-anchored maxillary expander (BAME) in adults. The sample comprised 18 patients (mean age, 29.9±9.4 years) selected for the MARPE group and 18 (mean age 24.8±6.8 years) selected for the BAME group. Cone-Beam computed tomography scans taken just before and after the expansion. After treatment, there was a significant palatal depth decrease. In addition, maxillary and mandibular width were increased in both groups. Regarding the cortical bone insertion and cortical bone width, it is shown an increase in both groups but those changes are not significant. However, the anterior suture opening effect occurs more frequently in the BAME than in the MARPE device. There are no differences in the frequency of opening of the midpalatal suture in the cases treated with MARPE and BAME, in both cases the most frequent opening morphology is parallel, independently of midpalatal suture maturation. There are no differences in the use of MARPE or BAME in the parallelism of the middle palatal suture, the cortical bone insertion, and thickness according to the maturation stages of the midpalatal suture but significantly increases the transverse dimensions of the maxillary skeleton.

Evaluation of the accuracy of full-arch impressions between three different intraoral scanners and conventional impressions: A prospective in vivo study.

This in-vivo study evaluated the accuracy of full-arch digital impressions obtained through different intraoral scanning technologies regarding trueness and efficiency against the standard alginate impressions. Alginate impressions were taken from 50 subjects, and the resulting stone casts were scanned using the Trios 3Shape desktop scanner. In-vivo scans were conducted on each participant using three intraoral scanners: Medit, CEREC Primescan, and 3Shape Trios. The scanned files were superimposed onto two software platforms: the 3Shape Orthoanalyser and Geomagic software. This superimposition was performed against the reference model to calculate 3D and 2D deviations, enabling efficiency comparisons between digital and traditional workflows based on work time in minutes. Measurements and comparisons were made in three planes: transverse, sagittal, and vertical dimensions for all the models and stone casts. Statistical analysis employed SPSS 23, with the significance level set at P<0.05. Significant deviations were observed between the three intraoral scanners and the alginate impression, with molar and premolar areas showing greater imprecision across dental arches. Compared to the alginate technique, Medit i500 tended to reduce the transverse dimension in the areas mentioned above, while CEREC exhibited higher precision. Molar and premolar areas emerged as the regions with the greatest discrepancies, both in excess and deficiency, compared to the alginate impression. This difference in dimensions was, however, statistically insignificant overall. 3Shape Trios exhibited the shortest scan times, indicating higher efficiency. Among the intraoral scanners, Medit recorded the longest scanning duration. Accepting the null hypothesis, the scans obtained using all three scanners were comparable with statistically insignificant differences in the measurements. The three scanners differed in the total scan time taken, with the Medit scanner requiring the longest scan time and the 3Shape TRIOS 3 scanner demonstrating the shortest scan duration.

The Complexity of Skeletal Transverse Dimension: From Diagnosis, Management, and Treatment Strategies to the Application of Collaborative Cross (CC) Mouse Model.

This study investigates the significance of skeletal transverse dimension (STD) in orthodontic therapy and its impact on occlusal relationships. The primary goal is to enhance understanding and promote the integration of transverse skeletal diagnostics into routine orthodontic assessments. To achieve this aim, the study employs a comprehensive approach, utilizing model analysis, clinical assessments, radiographic measurements, and occlusograms. The initial step involves a meticulous assessment of deficiencies in the maxilla, mainly focusing on transverse dimension issues. Various successful diagnostic methods are employed to ascertain the type and presence of these deficiencies. Furthermore, the study compares surgically assisted maxillary expansion (SARME) and orthopedic maxillary expansion (OME) in addressing skeletal transverse issues. Stability assessments and efficacy analyses are conducted to provide valuable insights into the superiority of SARME over OME. The findings reveal that proper evaluation of STD is crucial in orthodontic diagnosis, as overlooking transverse dimension issues can lead to complications such as increased masticatory muscle activity, occlusal interferences, and an elevated risk of gingival recession. Surgically assisted maxillary expansion emerges as a more stable solution than orthopedic methods. In conclusion, incorporating skeletal transverse diagnostics into routine orthodontic assessments is imperative for achieving optimal occlusal relationships and minimizing negative consequences on dentition, periodontium, and joints. The study emphasizes the significance of accurate three-dimensional assessments and recommends the consideration of SARME over OME for addressing skeletal transverse deficiencies. Finally, the Collaborative Cross (CC) mouse model is also a novel mouse model for studying complex traits. Exploring the Collaborative Cross mouse model opens avenues for future research, promising further insights into transverse skeletal issues in orthodontics.

An exploration of the enigmatic ponticulus posticus: a cone beam computed tomographic study

During embryonic development, the activity of neural crest cells has the potential to induce the ossification of the posterior atlantooccipital ligament, resulting in the formation of an abnormal bony bridge known as “Ponticulus Posticus” (PP). The presence of PP increases the likelihood of vertebral artery obstruction, and patients with this condition frequently exhibit symptoms of vertebrobasilar insufficiency. Furthermore, connections have been depicted between PP and dental agenesis, malocclusions, and cleft lip and palate. This study assessed the prevalence, morphology, and superior articular facet (SAF) dimensions in PP using Cone Beam Computed Tomography (CBCT). In this retrospective study, SPSS 22.0 was used to analyse 202 cervical CBCT images devoid of pathologies. PP, age, and sex relationship were examined using the t-test and chi2 analysis. Pearson correlation examined the relationship between PP and non-PP SAF dimensional differences. P values &lt;0.05 were significant. The prevalence of PP was 8.4%, with 64.7% constituting complete type and 35.2% partial type. The unilateral partial group’s anteroposterior (D1) and transverse (D2) dimensions showed a strong positive association and significant difference. Understanding this anomaly and the changes it can cause in depth is essential for a clinician to diagnose orofacial pain. Taking into account the benefits of using CBCT enables a detailed evaluation of the vertebral column in three different planes, allowing us to measure the metrical dimensions of SAF precisely in the present study. It can be considered a gold standard in evaluating PP as a diagnostic tool.

Mechanical strength measurement of needle-shaped CaSO4 microcrystals by a three-point bend test

A simple method for direct measurement of the mechanical strength of needle-shaped microcrystals of calcium sulfate, CaSO4, is proposed. The microcrystals, with a length from 30 to 50 μm and transverse dimensions from 1 to 3 μm, can act as reinforcing filler in various structural and building composites to improve their mechanical properties. The method is based on a three-point bend test, adapted to microscopic objects. The CaSO4 microcrystals were placed on a substrate, which was a twill-weave filter mesh consisting of intertwined steel fibers with diameter of ∼25 μm. Due to the twill weave, the mesh surface is characterized by a periodic distribution of protrusions and depressions. The protrusions act as supports for the placing of microcrystals, and the depressions provide the possibility of deformation and destruction of microcrystals under the action of an increasing vertically acting force, which is applied to the microcrystal through the indenter of the dynamic ultra-micro hardness tester. The moment of destruction of the microcrystals is observed to be dependent on the force on the displacement of the indenter. The measured values of the mechanical strength of CaSO4 microcrystals varied in a range from ∼3.5 to ∼6.0 GPa. The experimental strength values are in good agreement with the values obtained from the results of numerical analysis of the stressed state formed in the volume of CaSO4 microcrystals during the three-point bend test.

Propagation-Invariant Space-Time Plasmonic Pulse in Subwavelength MIM Waveguide.

The metal-insulator-metal (MIM) plasmonic waveguide has been highly anticipated for confining and guiding surface plasmon polaritons (SPPs) on the subwavelength scale. However, perennial drawbacks such as a short propagation length and an unbounded transverse field have set limits on the use of the MIM waveguide in various applications. Herein, diffraction- and dispersion-free MIM modes are synthesized by using space-time wave packets (STWPs) and are therefore referred to as space-time MIM (ST-MIM) waveguide modes. Compared to a Gaussian pulse of the same duration and spectral bandwidth, the ST-MIM demonstrates enhanced propagation lengths of about 2.4 times for the symmetric mode and about 6.3 times for the antisymmetric mode. In the simulations, the ST-MIMs are confined in all transverse dimensions, thereby overriding the diffraction limits. In addition, the group velocities of the ST-MIMs can be arbitrarily designed, which makes it possible to synchronize the pulse propagation speeds of the symmetric and antisymmetric MIM modes.