Adjustable rotation of multiple vortices produced by diode-pumped Nd:YVO4 lasers using intracavity second harmonic generation.

The criteria for achieving adjustable rotation of optical vortices are analyzed and used to design a diode-pumped solid-state laser that incorporates intracavity second harmonic generation within a concave-flat cavity to produce frequency-doubled Hermite-Gaussian (FDHG) modes. These FDHG modes are subsequently employed to generate various structured lights containing 2, 4, and 6 nested vortices using an external cylindrical mode converter. Through theoretical exploration, we propose that increasing the radius of curvature of the concave mirror and extending the cavity length can enhance the rotational angles of multiple vortices by expanding the adjustable range of phase shift for FDHG modes. Moreover, theoretical analyses assess vortex rotation concerning the positions of a nonlinear medium, successfully validating the experimental observations and elucidating the phase structures of the transformed beams.

Exploring intrusions without awareness: A preliminary study of the characteristics and influences of meta-awareness failures.

BACKGROUND AND OBJECTIVES: Research shows that people can lack meta-awareness (i.e., being explicitly aware) of their trauma-related thoughts, which impacts our understanding of re-experiencing symptoms, a key symptom type in posttraumatic stress disorder (PTSD), assessed through self-report. This preliminarily study explored differences between (meta-)aware and unaware intrusion characteristics to understand why some intrusions are not immediately apparent to individuals. METHODS: Trauma-exposed participants (N = 78) were recruited from online crowd-sourcing platforms to complete an online meta-awareness task. During a reading task, participants were intermittently probed to index the occurrence of unreported (i.e., unaware) trauma-related intrusions. Once participants indicated trauma-related intrusions were present, they then completed a questionnaire that indexed intrusion characteristics. RESULTS: Although unaware intrusions did occur in a subset of the sample, there were no fundamental differences between aware and unaware intrusions in terms of modality of experience (imagery vs. non-imagery), meaningfulness, accessibility, or other characteristics (e.g., vividness). LIMITATIONS: There was potential for lower participant engagement and attention due to the online delivery of the meta-awareness task, which may have minimized meta-awareness failure. Future research could consider using a continuous measure to index levels of meta-awareness. In addition, recruiting clinical samples (e.g., individuals with PTSD) who typically experience multiple daily intrusions would allow generalizability of the current findings to be tested. CONCLUSIONS: Our findings from this preliminary study suggest that unaware and aware intrusions show more commonality than not in their characteristics, with further research required to improve our understanding of the mechanisms leading to meta-awareness or lack of in PTSD.

Orbital angular momentum densities in the astigmatic transformation of Lissajous geometric laser modes.

Orbital angular momentum densities in the astigmatic transformation of Lissajous geometric laser modes are originally and systematically investigated. The quantum theory of the coherent state is exploited to derive an analytical wave representation for the transformed output beams. The derived wave function is further employed to numerically analyze the propagation dependent orbital angular momentum densities. The parts of the negative and positive regions in the orbital angular momentum density are found to rapidly change in the Rayleigh range behind the transformation.

Investigating the generation and propagation evolution of orange optical vortices using continuous-wave KGW Raman lasers with astigmatic mode transformations.

Various high-order orange beams (HOBs) at 588 nm are produced via off-center pumped Nd:YVO4/KGW Raman lasers. We experimentally confirm that the HOBs can be fairly sustained at the incident pump power of 2.88 W, where the average output powers are overall from 300 mW to 160 mW with increasing the off-center displacements from 0.14 mm to 0.21 mm. The HOBs are further transformed by using an astigmatic mode converter to generate a variety of structured lights with optical vortices. Moreover, theoretical wave functions are analytically derived to characterize the propagation evolution of the converted HOBs. The experimental patterns for all propagating positions are excellently reconstructed by the derived wave functions, and the evolution of phase structures is numerically calculated to manifest the robust optical vortices.

Structured transverse modes governed by maximum entropy principle.

Based on the birefringent effect of the gain medium, a diode-pumped Nd-doped vanadate laser with nearly hemispherical cavity is exploited to emulate the quantum Green functions of two-dimensional commensurate harmonic oscillators. By matching the theoretical calculations to the far-field patterns of lasing modes, the resonant transverse frequencies can be accurately determined up to extremely high orders. The Shannon entropy is further employed to calculate the spatial entanglement of the quantum Green function as a function the transverse frequency. From the resonant transverse frequencies, all lasing modes are confirmed to be in excellent agreement with the maximum entropy states. This discovery implies that the formation of lasing modes is relevant to the coupling interaction between the pump source and the laser cavity.

Are Individuals Always Aware of Their Trauma-Related Intrusive Thoughts? A Study of Meta-Awareness.

Individuals are not always aware of their mental content. We tested whether lack of awareness occurs in those who have experienced trauma, with and without posttraumatic stress disorder (PTSD). We also examined the role of proposed cognitive mechanisms (working memory and inhibition) in explaining unnoticed intrusions. Individuals with PTSD (n = 44), and varying levels of symptoms (high posttraumatic stress [PTS]: n = 24; low PTS: n = 37) reported on intrusive thoughts throughout a reading task. Intermittently, participants responded to probes about whether their thoughts were trauma related. Participants were "caught" engaging in unreported trauma-related thoughts (unnoticed intrusions) for between 24 and 27% of the probes in the PTSD and high PTS groups, compared with 15% of occasions in the low PTS group. For trauma-related intrusions only, participants lacked meta-awareness for almost 40% of probes in the PTSD group, which was significantly less than that observed in the other groups (∼60%). Contrary to predictions, working memory and response inhibition did not predict unnoticed intrusions. The results suggest that individuals who have experienced significant trauma can lack awareness about the frequency of their trauma-related thoughts. Further research is warranted to identify the mechanisms underpinning the occurrence of unnoticed intrusions.

High-power structured laser modes: manifestation of quantum Green's function.

The distributions of resonant frequencies in an astigmatic cavity are theoretically confirmed to be analogously equivalent to the quantum energy structures of two-dimensional commensurate harmonic oscillators. In the first part [Opt. Lett.45, 4096 (2020)OPLEDP0146-959210.1364/OL.399251] of this two-part series study, the lasing modes were verified to reveal a variety of vortex array structures. Here, in the second part of this two-part series study, the lasing modes are confirmed to agree very well with the quantum Green's functions that correspond to a bundle of Lissajous figures in the high-order regime.

High-power structured laser modes: direct generation of a vortex array.

The frequency degeneracy induced by the astigmatism in a nearly hemispherical cavity is originally exploited to generate vortex array laser modes with the output power up to 300 mW. The inhomogeneous Helmholtz equation is employed to derive the wave function for manifesting the characteristics of the lasing modes. The theoretical wave function explicitly reveals the role of the Gouy phase in the formation of vortex arrays. Numerical analyses are further performed to confirm that the thermal lensing effect in the laser crystal assists the lasing transverse order to increase with increasing pump power. It is believed that the high efficiency enables the present laser modes to be useful in the applications of structured vortex beams.

Generalized wave-packet formulation with ray-wave connections for geometric modes in degenerate astigmatic laser resonators.

The parametric equations for periodic rays in degenerate astigmatic laser resonators are derived in a generalized way. The derived parametric equations clearly reveal the formation of Lissajous geometric modes with phase variation along the propagation. Using the representation of a quantum coherent state, a generalized wave-packet formula is derived to connect with the periodic rays of geometric modes. The derived wave-packet formula is not only validated through comparing with various experimental patterns, but also is directly exploited to manifest the spatial asymmetries of Lissajous lasing modes due to a highly transmissive output coupler.

Genome-wide association and epidemiological analyses reveal common genetic origins between uterine leiomyomata and endometriosis.

Uterine leiomyomata (UL) are the most common neoplasms of the female reproductive tract and primary cause for hysterectomy, leading to considerable morbidity and high economic burden. Here we conduct a GWAS meta-analysis in 35,474 cases and 267,505 female controls of European ancestry, identifying eight novel genome-wide significant (P < 5 × 10-8) loci, in addition to confirming 21 previously reported loci, including multiple independent signals at 10 loci. Phenotypic stratification of UL by heavy menstrual bleeding in 3409 cases and 199,171 female controls reveals genome-wide significant associations at three of the 29 UL loci: 5p15.33 (TERT), 5q35.2 (FGFR4) and 11q22.3 (ATM). Four loci identified in the meta-analysis are also associated with endometriosis risk; an epidemiological meta-analysis across 402,868 women suggests at least a doubling of risk for UL diagnosis among those with a history of endometriosis. These findings increase our understanding of genetic contribution and biology underlying UL development, and suggest overlapping genetic origins with endometriosis.

Palliative care for cancer patients near end of life in acute-care hospitals across Canada: a look at the inpatient palliative care code.

Hospitals play an important role in the care of patients with advanced cancer: nearly half of all cancer deaths occur in acute-care settings. The need for increasing access to palliative care and related support services for patients with cancer in acute-care hospitals is therefore growing. Here, we examine how often and how early in their illness patients with cancer might be receiving palliative care services in the 2 years before their death in an acute-care hospital in Canada. The palliative care code from inpatient administrative databases was used as a proxy for receiving, or being referred for, palliative care. Currently, the palliative care code is the only data element routinely collected from patient charts that allows for the tracking of palliative care activity at a pan-Canadian level. Our findings suggest that most patients with cancer who die in an acute-care hospital receive a palliative designation; however, many of those patients are identified as palliative only in their final admission before death. Of the patients who received a palliative designation before their final admission, nearly half were identified as palliative less than 2 months before death. Findings signal that delivery of services within and between jurisdictions is not consistent, that the palliative care needs of some patients are being missed by physicians, and that palliative care is still largely seen as end-of-life care and is not recognized as an integral component of cancer care. Measuring the provision of system-wide palliative care remains a challenge because comprehensive national data about palliative care are not currently reported from all sectors. To advance measurement and reporting of palliative care in Canada, attention should be focused on collecting comparable data from regional and provincial palliative care programs that individually capture data about palliative care delivery in all health care sectors.

Origin of continuous curves and dotted spots in laser transverse modes with geometric structures.

The transverse structures of geometric modes in degenerate laser resonators with large astigmatism are systematically investigated by starting from the Gaussian wave packet formulation with ray-wave connections. The overlapping degree D between Gaussian wave packets is derived as an analytic expression that manifests the critical overlapping with D=1. The transverse patterns are confirmed to display a structure of continuous curves or dotted spots, depending on D>1 or D<1, respectively. A thorough comparison between experimental results and numerical calculations is performed to validate the theoretical analysis.

Bottle beam generation from a frequency-doubled Nd:YVO4 laser.

We demonstrate, for the first time, the direct generation of a bottle beam with a well-isolated three-dimensional zero-intensity dark core (high potential barrier) from a compact intracavity frequency-doubled Nd:YVO4 laser with a nearly hemispherical cavity. We also numerically calculate the physical properties of the generated bottle beam using a coherent superposition of a series of frequency-locked Laguerre-Gaussian modes.

Guidance on the management of familial hypercholesterolaemia in Hong Kong: an expert panel consensus viewpoin.

In 2016, meetings of groups of physicians and paediatricians with a special interest in lipid disorders and familial hypercholesterolaemia were held to discuss several domains of management of familial hypercholesterolaemia in adults and children in Hong Kong. After reviewing the evidence and guidelines for the diagnosis, screening, and management of familial hypercholesterolaemia, consensus was reached on the following aspects: clinical features, diagnostic criteria, screening in adults, screening in children, management in relation to target plasma low-density lipoprotein cholesterol levels, detection of atherosclerosis, lifestyle and behaviour modification, and pharmacotherapy.

The north-south and east-west gradient in colorectal cancer risk: a look at the distribution of modifiable risk factors and incidence across Canada.

Colorectal cancer (crc) is the 2nd most common cancer in Canada and the 2nd leading cause of cancer death. That heavy burden can be mitigated given the preventability of crc through lifestyle changes and screening. Here, we describe the extent of the variation in crc incidence rates across Canada and the disparities, by jurisdiction, in the prevalence of modifiable risk factors known to contribute to the crc burden. Findings suggest that there is a north-south and east-west gradient in crc modifiable risk factors, including excess weight, physical inactivity, excessive alcohol consumption, and low fruit and vegetable consumption, with the highest prevalence of risk factors typically found in the territories and Atlantic provinces. In general, that pattern reflects the crc incidence rates seen across Canada. Given the substantial interjurisdictional variation, more work is needed to increase prevention efforts, including promoting a healthier diet and lifestyle, especially in jurisdictions facing disproportionately higher burdens of crc. Based on current knowledge, the most effective approaches to reduce the burden of crc include adopting public policies that create healthier environments in which people live, work, learn, and play; making healthy choices easier; and continuing to emphasize screening and early detection. Strategic approaches to modifiable risk factors and mechanisms for early cancer detection have the potential to translate into positive effects for population health and fewer Canadians developing and dying from cancer.