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ABSTRACT Objective: Measure the diameter and thickness of the C6 and C7 pedicles using computed tomography, to analyze the security of the act surgery and the difference between males and females. Methods: This is a retrospective study. Two hundred computerized tomography scans of the cervical spine, one hundred male and one hundred female, from the Hospital Santa Teresa Radiology sector were evaluated. The pedicle thickness was measured in the axial plane, and the height was measured in sagittal slices. The student’s t-test was used to compare differences between the sexes, and a p-value lower than 0.05 was considered significant. Results: The mean age of the individuals included in the sample was 35±9 years. The mean height of the C6 and C7 pedicles were 7.1±0.9 mm and 7.8±0.9 mm, respectively. The mean thickness of the C6 and C7 pedicles were 5.2±0.7 mm and 5.9±0.8 mm, respectively. The statistical test showed that the values were significantly lower for female patients. Conclusions: The present study demonstrated parameters that can be used and can be the rule for preoperative planning of transpedicular cervical fixation surgeries, both in C6 and C7. As it is a procedure that can cause iatrogenic damage to important structures, the screw size must be chosen with care in pre-operative planning to avoid vessel rupture or damage to adjacent nerves. Level of Evidence III; retrospective study.

Since stepping into education delivery, technology continues to revolutionise education, responding to access and equity. This has made online learning to be the choice for access and equity like never seen before. Unfortunately, it has not only provided solutions but also introduced issues that have created the divide in technology and online learning for learners and institutions. The study explored online learning in the Solomon Islands from students' narratives at the Solomon Islands National University via tok stori; seeking to understand what they perceived as enablers and barriers of online learning. The study employed the sequential mixed-method approach and was guided by the theories of transactional distance and interaction, with the latter's extensions. The findings show that the level and strategies of support in administration, academics, and technology determine what transpires as an enabler or a barrier to online learning. [ABSTRACT FROM AUTHOR]

The author examines the relationship between the aesthetics of Romanticism and theories developed within the 20th century structuralist tradition. In the first part of the article he shows that there are affinities between the broad Romantic concept of the unifying symbol and the way linguistic entities are considered as self-contained units within certain theories of classical structuralism. In the last part he shows how poststructuralism tends to focus on rhetorical devices that display disruption rather than integration and unity, theorists such as Paul de Man taking a philosophical stance that amplifies the rupture between man – as a creature that allegedly relates to reality exclusively through linguistic means – and a multifaceted world that, according to the author, deserves better.

We show that ultrafast electron diffuse (inelastic) scattering provides a detailed, momentum-resolved view of electron-phonon and phonon-phonon coupling across the entire Brillouin zone. Ultrafast time-resolution and scattering selection rules can distinguish between phonon branches without energy-resolution.

A novel laser-RF cavity synchronization scheme was developed for ultrafast electron diffraction instruments. The approach directly generates a synchronized microwave tone by retrieving a phase-locked high-harmonic by photodetection. The radio-frequency cavity which performs electron pulse compression is detuning compensated using an active phase stabilization loop. Timing stability improved from 100 fs to 5 fs RMS and long-term time-zero stability improved to below our measurement resolution of 50 fs determined by pulse streaking.

Molybdenum disulfide (MoS2) has great potential as a two‐dimensional semiconductor for electronic and optoelectronic application, but its high sensitivity to environmental adsorbents and charge transfer from neighboring dielectrics can lead to device variability and instability. Aluminum oxide (Al2O3) is widely used as an encapsulation layer in (opto)‐electronics, but it leads to detrimental charge transfer n‐doping to MoS2. Here, this work reports a scalable encapsulation approach for MoS2 field‐effect transistors (FETs) where hexagonal boron nitride (h‐BN) monolayers are employed as a barrier layer in‐between each of the Al2O3 and MoS2 interfaces. These devices exhibit a significant reduction of charge transfer, when compared to structures without h‐BN. This benefit of h‐BN in the gate stack is confirmed by ab initio density functional theory calculations. In addition, the devices with h‐BN layers show very low hysteresis even under ambient operating conditions. [ABSTRACT FROM AUTHOR]

We present a natural standard translation of inquisitive modal logic $\mathrm{InqML}$ into first-order logic over the natural two-sorted relational representations of the intended models, which captures the built-in higher-order features of $\mathrm{InqML}$. This translation is based on a graded notion of flatness that ties the inherent second-order, team-semantic features of $\mathrm{InqML}$ over information states to subsets or tuples of bounded size. A natural notion of pseudo-models, which relaxes the non-elementary constraints on the intended models, gives rise to an elementary, purely model-theoretic proof of the compactness property for $\mathrm{InqML}$. Moreover, we prove a Hennessy-Milner theorem for $\mathrm{InqML}$ , which crucially uses $\omega $ -saturated pseudo-models and the new standard translation. As corollaries we also obtain van Benthem style characterisation theorems. [ABSTRACT FROM AUTHOR]

SnSe is a layered material that currently holds the record for bulk thermoelectric efficiency. The primary determinant of this high efficiency is thought to be the anomalously low thermal conductivity resulting from strong anharmonic coupling within the phonon system. Here we show that the nature of the carrier system in SnSe is also determined by strong coupling to phonons by directly visualizing polaron formation in the material. We employ ultrafast electron diffraction and diffuse scattering to track the response of phonons in both momentum and time to the photodoping of free carriers across the bandgap, observing the bimodal and anisotropic lattice distortions that drive carrier localization. Relatively large (18.7 Å), quasi-one-dimensional (1D) polarons are formed on the 300-fs timescale with smaller (4.2 Å) 3D polarons taking an order of magnitude longer (4 ps) to form. This difference appears to be a consequence of the profoundly anisotropic electron-phonon coupling in SnSe, with strong Fröhlich coupling only to zone-center polar optical phonons. These results demonstrate a high density of polarons in SnSe at optimal doping levels. Strong electron-phonon coupling is critical to the thermoelectric performance of this benchmark material and, potentially, high performance thermoelectrics more generally. [ABSTRACT FROM AUTHOR]