Prevalence of Anxiety in University Students during the COVID-19 Pandemic: A Systematic Review.

There is a dearth of evidence synthesis on the prevalence of anxiety among university students even though the risk of psychological disorders among this population is quite high. We conducted a quantitative systematic review to estimate the global prevalence of anxiety among university students during the COVID-19 pandemic. A systematic search for cross-sectional studies on PubMed, Scopus, and PsycINFO, using PRISMA guidelines, was conducted from September 2020 to February 2021. A total of 36 studies were included, using a random-effects model to calculate the pooled proportion of anxiety. A meta-analysis of the prevalence estimate of anxiety yielded a summary prevalence of 41% (95% CI = 0.34-0.49), with statistically significant evidence of between-study heterogeneity (Q = 80801.97, I2 = 100%, p ≤ 0.0001). A subgroup analysis reported anxiety prevalence in Asia as 33% (95% CI:0.25-0.43), the prevalence of anxiety in Europe as 51% (95% CI: 0.44-0.59), and the highest prevalence of anxiety in the USA as 56% (95% CI: 0.44-0.67). A subgroup gender-based analysis reported the prevalence of anxiety in females as 43% (95% CI:0.29-0.58) compared to males with an anxiety prevalence of 39% (95% CI:0.29-0.50). University students seem to have a high prevalence of anxiety, indicating an increased mental health burden during this pandemic.

Imaging articular cartilage under compression--cartilage elastography.

We constructed a device to compress small samples of articular cartilage while the samples were imaged in a 1.5 T imager. With the use of a piezoelectric piston, the device compressed 1-cm-diameter cylindrical samples of articular cartilage (200 microm) at a rate of 2 Hz. Simultaneously, we imaged the samples with a displacement-sensitive stimulated-echo acquisition mode (STEAM) sequence. We validated the technique using tissue that mimicked silicone samples. We compared the results from the same cartilage samples before and after they were degraded by digestion in trypsin. The extent of degradation was visualized from T(1)-weighted images of the samples after they were soaked in 0.5 mmolar of GdDTPA. The resulting elastographic images show compression and differential strain in directions both parallel and perpendicular to the surface of the cartilage. The static elastographic images that depict compression made before digestion and after 5 and 15 hr of trypsin digestion show that the elastic modulus of the samples decreased with a spatial variation consistent with the enzymatic digestion as revealed by the T(1) images. We believe this technique will be useful in studies of the mechanical properties of articular cartilage and other tissues, and may in the future be extended to the clinical setting.

MicroCT scanner performance and considerations for vascular specimen imaging.

Obtaining three-dimensional geometrical data of vascular systems is of major importance to a number of research areas in medicine and biology. Examples are the characterization of tumor vasculature, modeling blood flow, or genetic effects on vascular development. The performance of the General Electric Medical Systems MS8 microCT scanner is examined in the context of these applications. The system is designed to acquire high-resolution images of specimens up to 5 cm in diameter. A maximum resolution of 38 lp/mm at the 10% modulation transfer function level or 22 microm full width at half maximum of the plane spread function can be achieved with 8.5 microm voxels and a 17 mm field of view. Three different contrast agents are discussed and applied for imaging of small animal vasculature: corrosion casting material Batson's No. 17 with an added lead pigment, silicon rubber MICROFIL MV122, and a suspension of barium sulfate (Baritop) in gelatin. Contrast for all of these agents was highly variable in different vessels as well as within the same vessel. Imaging of PMMA tubing filled with MICROFIL shows that even vessels below 20 microm in diameter are detectable and that diameter estimation of vessels based on thresholding is possible with a precision of 2-3 pixels.