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The emergence of twisted metamaterials opens up an avenue for research in metamaterials. However, the current emphasis primarily lies in mechanics, rendering it intriguing to explore the application of compression-torsion coupling effect in optics. This present study introduces a thin-walled circular tube (TWCT) structure, characterized by a pronounced twisting angle of up to 59.5°, achieved only through a single-layer TWCT configuration. We demonstrate a significant compression-torsion coupling phenomenon, surpassing the findings of previous research endeavors. TWCT's deformation mechanism is harnessed in optical imaging through the integration of experimental, theoretical, and finite element approaches. The information stored in TWCT can be gradually projected through optical imaging when the elastic strain stimulates TWCT. These findings presented herein introduces a straightforward and valid approach to employ TWCT as a reliable mechanical switch for optical imaging, thereby showcasing its potential in the fields of cryptographic techniques, information storage, and transmission via optical imaging. [ABSTRACT FROM AUTHOR]

The study of bionic metamaterials with unique properties has gained increasing attention in recent years. This article introduces a double fish‐shaped metamaterial (DFSM) and investigates its elasticity and deformation behaviors. The Poisson's ratio of DFSM is derived from the energy principle and Mohr's theorem. The bending deformation behaviors of DFSM under given elastic strains are observed and tested by using the homemade experimental bench, which is further compared with finite element (FE) methods. The FE results show good agreement with experimental results. The bending vibration of DFSM under elastic tension is recorded and analyzed using a homemade prestrain bench in conjunction with a high‐speed camera. The present study proposes a straightforward and valid approach for incorporating the variable bending stiffness and the variable bending damping into DFSM. The revealed mechanical properties of DFSM in this article demonstrate its potential for engineering applications that require multistiffness and multidamping capabilities. [ABSTRACT FROM AUTHOR]

Abstract Background HIV infections which are diagnosed at advanced stages are associated with significantly poorer health outcomes. In Germany, the proportion of persons living with HIV who are diagnosed at later stages has remained continuously high. This study examined the impact of regional socioeconomic deprivation on the timing of HIV diagnosis. Methods We used data from the national statutory notification of newly diagnosed HIV infections between 2011 and 2018 with further information on the timing of diagnosis determined by the BED-Capture-ELISA test (BED-CEIA) and diagnosing physicians. Data on regional socioeconomic deprivation were derived from the German Index of Socioeconomic Deprivation (GISD). Outcome measures were a non-recent infection based on the BED-CEIA result or an infection at the stage of AIDS. The effect of socioeconomic deprivation on the timing of diagnosis was analysed using multivariable Poisson regression models with cluster-robust error variance. Results Overall, 67.5% (n = 10,810) of the persons were diagnosed with a non-recent infection and 15.2% (n = 2746) with AIDS. The proportions were higher among persons with heterosexual contact compared to men who have sex with men (MSM) (76.8% non-recent and 14.9% AIDS vs. 61.7% non-recent and 11.4% AIDS). MSM living in highly deprived regions in the countryside (

Objectives: This study examined the incidence rates and predictive utility of established prognostic factors for the progression to AIDS among people living with HIV under clinical care. Methods: We used data from two observational cohorts of people living with HIV in Germany between 1999 and 2018. The outcome measure was the first AIDS‐defining event that occurred during follow‐up. Incidence rates (IRs) per 1000 person‐years (PY) were calculated by years of follow‐up and calendar periods. We used Cox models in our prediction analyses, including CD4 count, viral load, and age at baseline to estimate the predictive performance. Additionally, we included transmission mode to examine its predictive utility. Results: A total of 23 299 people living with HIV were included in the analyses. Of these, 1832 developed a first AIDS event during follow‐up, constituting an overall rate of 14.6/1000 PY (95% confidence interval [CI] 13.9–15.2). IRs were highest in the first year of follow‐up (45.6/1000 PY, 95% CI 42.6–48.8) and then declined continuously. IRs were highest among people living with HIV who enrolled between 1999 and 2003 (36.1/1000 PY, 95% CI 32.6–40.0). A low CD4 count, high viral load, and older age at baseline increased the likelihood of progressing to AIDS. Adding transmission mode to the models did not improve the predictive performance. Conclusions: The rates of a first AIDS event among people living with HIV have continuously declined in Germany. Health outcomes depend on a person's CD4 count, viral load, and age but not on transmission mode. To further reduce the number of AIDS cases, the focus should be on groups more likely to present in progressed stages of their HIV infection. [ABSTRACT FROM AUTHOR]

Little is known of the influence of scanner field strength on quantitative diffusivity variables, especially kurtosis in healthy ovaries.To evaluate the influence of scanner field strength on quantitative diffusion variables in pelvic MRI of the ovaries.This prospective, single-centre study consisted of repeated 1.5-T and 3-T examinations in 30 female volunteers (mean age=27.9 years, age range=20.3–45.2 years) from July 2017 to September 2019. Multi b-value DWI 0, 50, 100, 800, 1500, 2000 s/mm2 was acquired over three timepoints during the menstrual cycle. Ovaries were segmented at b = 1500 s/mm2. Median apparent diffusion coefficient (ADC) and advanced kurtosis parameters Dapp and Kapp were calculated. Statistical analysis was performed with the variations of diffusivity variables being compared between 1.5-T and 3-T MRI using a Mann–Whitney rank-sum test.Median ADC and Dapp (µm²/ms) did not statistically differ. Median ADC were 1.509 (range=1.371–1.610), 1.619 (range=1.463–1.747), and 1.511 (range=1.423–1.639) at 1.5 T; 1.542 (range=1.428–1.682), 1.658 (range=1.510–1.806), and 1.572 (range=1.455–1.709) at 3 T (P = 0.14, 0.19, and 0.07), whereas median Dapp were 2.024 (range=1.913–2.152), 2.192 (range=2.010–2.327), and 2.045 (range=1.958–2.170) at 1.5 T; 2.013 (range=1.952–2.188), 2.179 (range=2.018–2.327), and 2.082 (range=1.959–2.194) at 3 T (P = 0.77, 0.99, and 0.34) for timepoints 1, 2, and 3, respectively. Statistical comparison of Kapp revealed significant differences for all timepoints: 0.629 (range=0.595–0.652), 0.604 (range=0.574–0.651), and 0.622 (range=0.581–0.664) at 1.5 T; 0.601 (range=0.563–0.626), 0.567 (range=0.526–0.633), and 0.599 (range=0.541–0.650) at 3 T (P < 0.001, 0.005, and 0.03).Diffusivity mapping in the ovaries provides similar absolute median diffusion values, but statistically significant differences in absolute kurtosis values between 1.5 T and 3 T. [ABSTRACT FROM AUTHOR]