Search Results (8)

Background: Cerebral palsy (CP) is the leading cause of permanent physical disability in children. Although hip surveillance is a global standard, spinal surveillance remains inconsistent, often leading to reactive rather than proactive management of neuromuscular scoliosis. This study aims to establish an international consensus on a risk-based spinal surveillance protocol. Methods: A three-round modified Delphi process was conducted in 2024 with 15 international pediatric spine surgeons, identified through purposive sampling. The process adhered to CREDES standards and focused on establishing standards for timing, frequency, and radiographic surveillance. Consensus thresholds were defined a priori as excellent (≥80%) and good (≥73%) agreement. Results: The panel reached excellent consensus (93%) on a “Traffic Light” system based on the Gross Motor Function Classification System (GMFCS) levels. Green Group (Walkers, GMFCS I–II): Clinical surveillance. Amber Group (Poor Walkers, GMFCS III, and asymmetric hemiplegic GMFCS I–II): Annual radiographs starting at ages 3–8. Red Group (Non-Walkers, GMFCS IV–V): Six-monthly radiographs starting at ages 3–5. There was 100% consensus on the mandatory use of sitting radiographs for non-ambulatory patients to prevent masking true pelvic decompensation. Critical referral triggers were identified as a Cobb angle >20°, pelvic obliquity ≥5°, or a progression rate ≥1° per month. Conclusions: The “Traffic Light” protocol helps identify the “window of opportunity” for intervention before reaching the 90° “point of no return,” where surgical risks increase nonlinearly. This proactive approach aims to reduce surgical complications and systemic delays in specialized care. Full article

Background: Canines play a vital functional and aesthetic role in human dentition, yet impacted canines, particularly in the mandible, are rare and can lead to functional disorders, such as the absence of canine guidance, while negatively affecting a patient’s self-esteem. Transmigration of mandibular canines adds complexity to treatment. One method to reduce the treatment time, especially for impacted teeth, is corticotomy-assisted orthodontic therapy (CAOT). Methods: A 13-year-old patient presented with a horizontally impacted lower right canine, positioned below the roots of the lower incisors, showing transmigration. A digitally designed and 3D-printed lingual appliance was attached to the lower molars with hooks on the lingual side, enabling the application of multi-directional orthodontic forces. CAOT was performed using an Er:YAG laser (LightWalker, Fotona, Ljubljana, Slovenia) at 200 mJ, 12 Hz, 2.4 W, with a pulse duration of 100 µs, and an MSP H14 conical tip (0.6 mm spot diameter). Photobiomodulation (PBM) with a 635 nm diode laser (Lasotronix, Smart ProM, Piaseczno, Poland) was applied at 10 J per point (20 J/cm²) for 100 s per point, with a total energy of 20 J per session to reduce the risk of root resorption, manage pain, and accelerate healing as the tooth was moved into the alveolar ridge. Results: The treatment duration was two and a half years. The lingual appliance with hooks allowed precise traction of the canine, aided by exposure from the lingual side and the attachment of a hook. Gentle forces applied via orthodontic thread gradually moved the canine beneath the oral mucosa. Mid-treatment cone beam computed tomography (CBCT) scans confirmed the absence of root resorption of the lower incisors. A corticotomy, enhanced by laser therapy, was performed before moving the canine into the alveolar ridge. The canine was successfully rotated 180° and positioned without any signs of resorption in the canine or adjacent teeth. Conclusions: The use of a digitally designed and 3D-printed lingual appliance with hooks allowed the precise control of the traction of impacted teeth. When combined with corticotomy and laser therapy, it minimised root resorption risks, reduced pain, accelerated healing, and improved the overall success of the orthodontic treatment. Full article

Human point-light displays consist of luminous dots representing human articulations, thus depicting actions without pictorial information. These stimuli are widely used in action recognition experiments. Because humans excel in decoding human motion, point-light displays (PLDs) are often masked with additional moving dots (noise masks), thereby challenging stimulus recognition. These noise masks are typically found within proprietary programming software, entail file format restrictions, and demand extensive programming skills. To address these limitations, we present the first user-friendly step-by-step guide to develop visual noise to mask PLDs using free, open-source software that offers compatibility with various file formats, features a graphical interface, and facilitates the manipulation of both 2D and 3D videos. Further, to validate our approach, we tested two generated masks in a pilot experiment with 12 subjects and demonstrated that they effectively jeopardised human agent recognition and, therefore, action visibility. In sum, the main advantages of the presented methodology are its cost-effectiveness and ease of use, making it appealing to novices in programming. This advancement holds the potential to stimulate young researchers’ use of PLDs, fostering further exploration and understanding of human motion perception. Full article

We point out that a modified temperature–redshift relation (T-z relation) of the cosmic microwave background (CMB) cannot be deduced by any observational method that appeals to an a priori thermalisation to the CMB temperature T of the excited states in a probe environment of independently determined redshift z. For example, this applies to quasar-light absorption by a damped Lyman-alpha system due to atomic as well as ionic fine-splitting transitions or molecular rotational bands. Similarly, the thermal Sunyaev-Zel’dovich (thSZ) effect cannot be used to extract the CMB’s T-z relation. This is because the relative line strengths between ground and excited states in the former and the CMB spectral distortion in the latter case both depend, apart from environment-specific normalisations, solely on the dimensionless spectral variable $x=\frac{h\nu }{k_{B}T}$. Since the literature on extractions of the CMB’s T-z relation always assumes (i) $\nu \left(z\right)=(1+z)\nu (z=0)$, where $\nu (z=0)$ is the observed frequency in the heliocentric rest frame, the finding (ii) $T\left(z\right)=(1+z)T(z=0)$ just confirms the expected blackbody nature of the interacting CMB at $z>0$. In contrast to the emission of isolated, directed radiation, whose frequency–redshift relation ($\nu$-z relation) is subject to (i), a non-conventional $\nu$-z relation $\nu \left(z\right)=f\left(z\right)\nu (z=0)$ of pure, isotropic blackbody radiation, subject to adiabatically slow cosmic expansion, necessarily has to follow that of the T-z relation $T\left(z\right)=f\left(z\right)T(z=0)$ and vice versa. In general, the function $f\left(z\right)$ is determined by the energy conservation of the CMB fluid in a Friedmann–Lemaitre–Robertson–Walker universe. If the pure CMB is subject to an SU(2) rather than a U(1) gauge principle, then $f\left(z\right)={\left(1/4\right)}^{1/3}(1+z)$ for $z\gg 1$, and $f\left(z\right)$ is non-linear for $z\sim 1$. Full article

We discuss a rigorous procedure for quantifying the difference between our past light cone and the past light cone of the fiducial Friedmann–Lemaitre–Robertson–Walker spacetime, modeling the large-scale descriptions of cosmological data in the standard $\Lambda \mathrm{CDM}$ scenario. This result is made possible by exploiting the scale-dependent distance functional between past light cones recently introduced by us. We express this harmonic map-type functional in terms of the physical quantities that characterize the actual measurements along our past light cone, namely the area distance and the lensing distortion, also addressing the very delicate problem of the presence of light cone caustics. This analysis works beautifully and seems to remove several of the difficulties encountered in comparing the actual geometry of our past light cone with the geometry of the fiducial FLRW light cone of choice. We also discuss how, from the point of view of the FLRW geometry, this distance functional may be interpreted as a scale-dependent effective field, the pre-homogeneity field, which may be of relevance in selecting the FLRW model that best fits the observational data. Full article

To perceive, identify and understand the action of others, it is essential to perceptually organize individual and local moving body parts (such as limbs) into the whole configuration of a human body in action. Configural processing—processing the relations among features or parts of a stimulus—is a fundamental ability in the perception of several important social stimuli, such as faces or biological motion. Despite this, we know very little about how human infants develop the ability to perceive and prefer configural relations in biological motion. We present two preferential looking experiments (one cross-sectional and one longitudinal) measuring infants’ preferential attention between a coherent motion configuration of a person walking vs. a scrambled point-light walker (i.e., a stimulus in which all configural relations were removed, thus, in which the perception of a person is impossible). We found that three-month-old infants prefer a coherent point-light walker in relation to a scrambled display, but both five- and seven-month-old infants do not show any preference. We discuss our findings in terms of the different perceptual, attentional, motor, and brain processes available at each age group, and how they dynamically interact with selective attention toward the coherent and socially relevant motion of a person walking during our first year of life. Full article

The confrontation between good and evil is one of the essential aspects of the fantasy genre. In George R.R. Martin’s epic fantasy novel series A Song of Ice and Fire (ASOIAF, 1996–2011), he approaches this conception from a critical point of view. Whilst Martin creates deep and challenging characters in his novels, he introduces the White Walkers to the audience as almost one-dimensional, classic antagonists. It can therefore be questioned whether this contradicts his approach towards the medieval ethos. In order to answer this question, I will approach the narration from the aspect of totemism, and will use totemic signs and values for my analysis. Firstly, I will establish a relationship between totemism and the Old Gods. Conceptions such as ‘sacred totem animal’, ‘totem as an emblem’, ‘restriction of incestuous intercourse’, and ‘spirits’ will be useful for comprehending the Old Gods. Furthermore, I will try to analyze the narration with the elements of totemism. Lastly, in the light of this examination, I will try to explain what theWhite Walkers represent within the narration. Full article

A number of previous works have shown that information about a subject is encoded in sparse kinematic information, such as the one revealed by so-called point light walkers. With the work at hand, we extend these results to classifications of soft biometrics from inertial sensor recordings at a single body location from a single step. We recorded accelerations and angular velocities of 26 subjects using integrated measurement units (IMUs) attached at four locations (chest, lower back, right wrist and left ankle) when performing standardized gait tasks. The collected data were segmented into individual walking steps. We trained random forest classifiers in order to estimate soft biometrics (gender, age and height). We applied two different validation methods to the process, 10-fold cross-validation and subject-wise cross-validation. For all three classification tasks, we achieve high accuracy values for all four sensor locations. From these results, we can conclude that the data of a single walking step (6D: accelerations and angular velocities) allow for a robust estimation of the gender, height and age of a person. Full article