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Our growing understanding of the plant tree of life provides a novel opportunity to uncover the major drivers of angiosperm diversity. Using a time-calibrated phylogeny, we characterized hot and cold spots of lineage diversification across the angiosperm tree of life by modeling evolutionary diversification using stepwise AIC (MEDUSA). We also tested the whole-genome duplication (WGD) radiation lag-time model, which postulates that increases in diversification tend to lag behind established WGD events. Diversification rates have been incredibly heterogeneous throughout the evolutionary history of angiosperms and reveal a pattern of ‘nested radiations’ – increases in net diversification nested within other radiations. This pattern in turn generates a negative relationship between clade age and diversity across both families and orders. We suggest that stochastically changing diversification rates across the phylogeny explain these patterns. Finally, we demonstrate significant statistical support for the WGD radiation lag-time model. Across angiosperms, nested shifts in diversification led to an overall increasing rate of net diversification and declining relative extinction rates through time. These diversification shifts are only rarely perfectly associated with WGD events, but commonly follow them after a lag period.

The flora of southern Africa is, for its latitude and area, very species-rich. Although the hyperdiverse Cape flora contributes almost half of this richness, three other radiations (desert, grassland, and woodland) contribute significantly to the botanical wealth of southern Africa. Each radiation occurs in a different ecological setting and has a different diversification history. Such parallel radiations can develop in suitably complex environments, given gradual change through time and no region-wide catastrophes. These four radiations cross-seeded each other, with clades spawning subclades in other radiations, thus linking all four into one complex radiation. This led to an increase in the number of diversifying clades in each radiation. Such complex radiations accumulate diversifying lineages over a long time, spawn daughter radiations on other continents, and become powerhouses of global-biodiversity generation. We suggest that several of the most species-rich regions may harbor such complex radiations.

In this paper, we propose a compact triple band microstrip antenna, whose performance is discussed and investigated by using full-wave simulation and measurements. To achieve expected triple-band characteristics, three nested loop radiation elements are presented and a rectangular stub connected to the feed line is also introduced. Our proposed antenna has a size of 28 mm×41 mm and a thickness of 1.5 mm, which is fed by a coplanar waveguide (CPW). The simulated and measured results show that the proposed antenna provides a tri-band characteristic that covers 2.1-2.8 GHz, 3.3-4.0 GHz and 5.5-5.8 GHz. The center frequencies of the designed triple bands can be controlled by adjusting the dimensions of the nested loop elements. As a result, the designed tri-band antenna has a good impedance matching characteristic and omnidirectional radiation patterns, which make the proposed antenna could be a favorable candidate for Bluetooth, WiMAX and WLAN applications.

This article investigates the innovative integration of a substrate-integrated waveguide (SIW) with a nested photonic bandgap (PBG) crystal to enhance the performance of a swiveled dielectric resonator antenna (DRA). The study focuses on designing the SIW, the PBG crystal, and the novel shape of the DRA, which is swiveled and embedded within the SIW and photonic crystal structure. The aperture-fed DRA is analyzed over the 0.1–10 THz frequency range. The proposed encapsulated SIW-PBG antenna demonstrates resonances at 2.5 THz, 3.5 THz, and 5.2 THz. Utilizing a periodically grooved silicon substrate surrounding the SIW significantly enhances the gain, achieving values of 6.75 dBi, 6.86 dBi, and 6.82 dBi, respectively. Rigorous parametric analysis is conducted to optimize the design and validate the results.

As a high-degree-of-freedom approach to manipulate the electromagnetic wave, metasurfaces are widely used in high-capacity information technology. Extensive investigations have explored multiplexing techniques using polarization, incident angle, wavelength, and infinite-dimensional multiplexing through Orbital Angular Momentum (OAM). However, due to the limited spatial resolution and array size of the metasurface, the number of multiplexing channels that can be actually realized is limited. Therefore, research on the combination of OAM multiplexing and polarization degrees of freedom is of great significance. Here, we propose and experimentally demonstrate a metasurface holography multiplexing scheme based on multiple polarization channels combined with OAM. Taking advantage of the orthogonal independence of spin angular momentum and orbital angular momentum, multiple OAM multiplexing holograms are constructed in multiple different spin-polarization channels. Utilizing the well-established compatibility between OAM multiplexing and polarization multiplexing, we successfully integrated two multiplane holograms and 15 OAM multiplexing holograms on a single metasurface. Subsequently, we introduced an optical nested encryption framework designed for parallel communication. This work facilitates high-capacity and high-security holography by employing multiplexing metasurfaces, thereby providing innovative design concepts for optical communication, information encryption, and related domains.

ObjectivesThere is growing evidence of an association between low-dose external γ-radiation and circulatory system diseases (CSDs), yet sparse data exist about an association with chronic internal uranium exposure and the role of non-radiation risk factors. We conducted a nested case–control study of French AREVA NC Pierrelatte nuclear workers employed between 1960 and 2005 to estimate CSD risks adjusting for major CSD risk factors (smoking, blood pressure, body mass index, total cholesterol and glycaemia) and external γ-radiation dose.MethodsThe study included 102 cases of death from CSD and 416 controls individually matched on age, gender, birth cohort and socio-professional status. Information on CSD risk factors was collected from occupational medical records. Organ-specific absorbed doses were estimated using biomonitoring data, taking into account exposure regime and uranium physicochemical properties. External γ-radiation was measured by individual dosimeter badges. Analysis was conducted with conditional logistic regression.ResultsWorkers were exposed to very low radiation doses (mean γ-radiation dose 2 and lung uranium dose 1 mGy). A positive but imprecise association was observed (excess OR per mGy 0.2, 95% CI 0.004 to 0.5). Results obtained after adjustment suggest that uranium exposure might be an independent CSD risk factor.ConclusionsOur results suggest that a positive association might exist between internal uranium exposure and CSD mortality, not confounded by CSD risk factors. Future work should focus on numerous uncertainties associated with internal uranium dose estimation and on understanding biological pathway of CSD after protracted low-dose internal radiation exposure.

This paper delves into the problem of direct position determination (DPD) for non-Gaussian sources. Existing DPD algorithms are hindered by their high computational complexity from exhaustive grid searches and a disregard for the received signal characteristics by multiple nested arrays (MNAs). To address these issues, the paper proposes a novel DPD algorithm for non-Gaussian sources with MNAs: the Discrete Fourier Transform (DFT) and Taylor compensation algorithm. Initially, the fourth-order cumulant matrix of the received signal is computed, and the vectorizing method is applied. Subsequently, a computationally efficient DPD cost function is proposed by leveraging a normalized DFT matrix to reduce complexity. Finally, first-order Taylor compensation is utilized to enhance the accuracy of the localization results. The superiority of the proposed algorithm is demonstrated through numerical simulation results.

The radiation response of cervical cancer is thought to be enhanced by the levels of melatonin due to its roles in the circadian cycle and cancer growth. In the present study, the roles of circadian rhythms and melatonin levels as prognostic factors for predicting the radiation response in patients with cervical cancer were examined. In this nested case-control study, patients with good and poor responses to radiotherapy were assessed in terms of the time-of-day radiation treatment was administered and further influencing factors. The radiation time was determined, as the subjects were either irradiated in the morning (06.00-10.00 am) or afternoon (04.00-06.00 pm). Data on tumour size and other biological parameters were collected and analysed by binary logistic regression. Among the 56 patients examined, most subjects had good radiation responses. Most patients were <50 years old with an initial body weight of >50 kg, no pain prior to radiation, low erythrocyte sedimentation rates, normal intravenous urography results, moderate or good differentiation on pathology and histo-pathologically non-keratinised cells. According to the multivariate analysis, the irradiation time as a surrogate of the circadian cycle (morning vs. afternoon), the initial haemoglobin (Hb) level and the clinical tumour size were significant predictors of the radiation response. The circadian cycle, tumour size and Hb levels may affect the radiation response in patients with cervical cancer. In addition, the morning group had better 5-year overall survival, but it was not significant, possibly due to the small cohort size. Further research is required to identify more relevant prognostic factors using different radiotherapy techniques [National Clinical Trial (NCT) no. NCT05511740, registration date, 08/20/2022].

BackgroundSubsequent primary neoplasms (SPN) are among the most severe late effects and the second most frequent cause of death in childhood cancer patients. In this paper we introduce method and properties of the STATT-SCAR study (Second Tumor After Tumor Therapy, Second Cancer After Radiotherapy), which is a joint nested matched case–control study to evaluate the impact of chemotherapy (STATT) as well as radiotherapy (SCAR) on the risk of developing a SPN.MethodsBased on the cohort of the German childhood cancer registry (GCCR), we selected patients diagnosed with a first neoplasm before age 15 or younger between 1980 and 2014. We selected those with a SPN at least half a year after the first neoplasm, and matched up to four controls to each case. Therapy data were acquired from various sources, including clinical study centers and treating hospitals. To analyze the impact of radiotherapy, organ doses were estimated by using reconstructed treatment plans. The effect of chemotherapy was analyzed using substance groups summarized after isotoxic dose conversion.Results1244 cases with a SPN were identified and matched with 4976 controls. Treatment data were acquired for 83% of all match groups (one case and at least one control). Based on preliminary analyses, 98% of all patients received chemotherapy and 54% of all patients were treated with radiotherapy.ConclusionsBased on our data, detailed analyses of dose response relationships and treatment element combinations are possible, leading to a deeper insight into SPN risks after cancer treatments.Trial registrationThe study is registered at the German clinical trial register (DRKS) under number DRKS00017847 [45].

Hollow-core optical fibers (HCFs) have unique properties like low latency, negligible optical nonlinearity, wide low-loss spectrum, up to 2100 nm, the ability to carry high power, and potentially lower loss then solid-core single-mode fibers (SMFs). These features make them very promising for communication networks and similar applications. However, this class of fibers is still in development. Current applications are almost exclusively limited to low-latency data links for High-Speed Trading (HST); other uses are in the trial stage now. In this paper, we comprehensively review the progress in the development of HCFs including fiber design, fabrication and parameters (with comparisons to conventional single-mode fibers) and support technologies like splicing and testing. A variety of HCF applications in future telecom networks and systems is analyzed, pointing out their strengths and limitations. Additionally, we review the influence of filler gas and entry of contaminants on HCF attenuation, and propose a new fusion splicing technique, avoiding the destruction of the fiber’s photonic cladding at high temperature.