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IMPORTANCE: The incidence of early-onset colorectal cancer (younger than 50 years) is rising globally, the reasons for which are unclear. It appears to represent a unique disease process with different clinical, pathological, and molecular characteristics compared with late-onset colorectal cancer. Data on oncological outcomes are limited, and sensitivity to conventional neoadjuvant and adjuvant therapy regimens appear to be unknown. The purpose of this review is to summarize the available literature on early-onset colorectal cancer. OBSERVATIONS: Within the next decade, it is estimated that 1 in 10 colon cancers and 1 in 4 rectal cancers will be diagnosed in adults younger than 50 years. Potential risk factors include a Westernized diet, obesity, antibiotic usage, and alterations in the gut microbiome. Although genetic predisposition plays a role, most cases are sporadic. The full spectrum of germline and somatic sequence variations implicated remains unknown. Younger patients typically present with descending colonic or rectal cancer, advanced disease stage, and unfavorable histopathological features. Despite being more likely to receive neoadjuvant and adjuvant therapy, patients with early-onset disease demonstrate comparable oncological outcomes with their older counterparts. CONCLUSIONS AND RELEVANCE: The clinicopathological features, underlying molecular profiles, and drivers of early-onset colorectal cancer differ from those of late-onset disease. Standardized, age-specific preventive, screening, diagnostic, and therapeutic strategies are required to optimize outcomes.

The upcoming hypersonic technologies pose a difficult task for air navigation systems. The article presents a designed model of elastic interaction of penetrating acoustic radiation with flat isotropic suspension elements of an inertial navigation sensor in the operational conditions of hypersonic flight. It has been shown that the acoustic transparency effect in the form of a spatial-frequency resonance becomes possible with simultaneous manifestation of the wave coincidence condition in the acoustic field and equality of the natural oscillation frequency of a finite-size plate and a forced oscillation frequency of an infinite plate. The effect can lead to additional measurement errors of the navigation system. Using the model, the worst and best case suspension oscillation frequencies can be determined, which will help during the design of a navigation system.

Supplemental Digital Content is Available in the Text.The aim of this study was to establish an international expert consensus on a detailed technical description of the laparoscopic total mesorectal excision using a structured, scientific process. This may have implications on training, assessment, quality control, and future research.

Consideration is given to the results of an analysis of the additional drift in a three-axial gyroplatform under the concurrent action of kinematic and acoustic stimuli.

We solve the boundary-value problem of nonstationary heat conduction in a layer between parallel planes by joint application of Fourier-Laplace integral transforms and thermal potentials. A relationship is established between the original multidimensional problem and some special one-dimensional problem of nonstationary heat conduction, which is solved numerically. As a result, we obtain a solution of the original multidimensional problem of heat conduction which can be conveniently used in practical calculations.

We present the results of an investigation of the stress-strains state of a mechanical system consisting of two coaxial circular cylinders connected by an elastic link under the action of external acoustic pressure waves. We establish regularities of the appearance of displacements of the elements of the surface of the circular cylinders and the characteristics of the state of the entire mechanical system under acoustic loading.

The article investigates the state of stress and strain of the surface of an elastic cylindrical shell whose outer part is subjected to the effect of an incident acoustic wave. A qualitative and quantitative analysis of the state of strain of the surface is carried out and recommendations are given for optimizing the functional purpose of the shell and minimizing the arising stresses.

The article presents a comparative qualitative and quantitative analysis of the state of stress and strain of the surface of a flat isotropic plate under acoustic load for three cases of state of stress and strain: space-frequency resonance, incomplete space-frequency resonance, and frequency resonance.

We demonstrate the applicability of a complete nonorthogonal system of Schauder functions to digital signal processing and signal compression. The digital signal processing algorithm is demonstrated in application to the compression of electrocardiogram signals.

A universal means of controlling noise, which effectively suppresses the noise pressure of both low- and high-intensity fields, is proposed. An apparatus in the form of a system of two metallic coaxial cylinders is developed. The outer cylinder has longitudinal through slits, through which some of the energy of the sound field strikes the internal cylinder. Reflecting from the latter, it strikes the inner wall of the outer cylinder, creating, in turn, a counter noise pressure; this gives rise to significant reduction in the sound level inside the apparatus.

The article establishes some novel features of the dynamics of rotor sirens. It contains a quantitative and qualitative evaluation of the effect of the Earth's rotational speed on the additional gyroscopic pressure to which the radial rotor bearings are subjected.