Vertical cavity surface-emitting lasers (VCSELs) have made indispensable contributions to the development of modern optoelectronic technologies. However, arbitrary beam shaping of VCSELs within a ...compact system has remained inaccessible until now. The emerging ultra-thin flat optical structures, namely metasurfaces, offer a powerful technique to manipulate electromagnetic fields with subwavelength spatial resolution. Here, we show that the monolithic integration of dielectric metasurfaces with VCSELs enables remarkable arbitrary control of the laser beam profiles, including self-collimation, Bessel and Vortex lasers, with high efficiency. Such wafer-level integration of metasurface through VCSEL-compatible technology simplifies the assembling process and preserves the high performance of the VCSELs. We envision that our approach can be implemented in various wide-field applications, such as optical fibre communications, laser printing, smartphones, optical sensing, face recognition, directional displays and ultra-compact light detection and ranging (LiDAR).
Objectives Most research into the management of pelvic inflammatory disease (PID) is in younger women and focuses on sexually transmitted pathogens such as N. gonorrhoeae or C. trachomatis. ...Non-sexually transmitted bacterial pathogens and PID in older women are rarely examined. The objective of this study is to explore cervical culture pathogens in women of different age groups in a medical center in eastern Taiwan. Methods We enrolled patients whose medical records were diagnosed with PID (ICD-9-CM 614.0 N70.01-03, 614.1N70.11-13, 614.9 N73.5, N73.9) at our hospital from October 2014 to March 2020. Patients were divided into three groups according to age: the age <25 years, age 25-44 years, and the greater than or equal to 45 years group. Chi-square test, ANOVA and logistic regression were used for statistical analysis. In subgroup analysis, endocervical pathogens were further stratified into vaginal, respiratory, enteric, skin, oral, and other. Results A total of 96 patients were included in the study. There were 31 patients in the age greater than or equal to 45 years group, 52 patients in the age 25-44 years group, and 13 patients in the age <25 years group. Vagina and enteric pathogens were the most common pathogens among all groups. The isolated respiratory and other pathogens were more in the age greater than or equal to 45 years group than in the other two groups. Prevotella bivia was more common in the age <25 years and 25-44 years groups. Conclusions This may be due to different pathogeneses of PID in the age greater than or equal to 45 years patients. Our study can be used as a reference for antibiotic choice of non-sexually transmitted PID and to prevent long-term sequelae of PID.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Opportunistic salpingectomies (OSs) are concurrently performed with hysterectomies to prevent epithelial ovarian cancer. This study aimed to investigate the correlation between OS and early menopause ...in females who have undergone hysterectomies. This was a retrospective cohort study involving 79 females who had undergone a hysterectomy, with or without an OS, between January 2007 and December 2015. Their ages at surgery, at menopause, and the lengths of time from surgery to menopause were compared. An OS had been performed in 54 and not performed in 25 of the enrolled patients, comprising the OS and non-OS groups. Body mass index was significantly higher in the OS group (OS: 25.27 ± 4.17 vs. non-OS: 22.97 ± 3.27,
= 0.01). Additionally, menopausal sleep problems were more prevalent in the OS group than in the non-OS group (41% vs. 12%,
= 0.01). Notably, the time from surgery to menopause was significantly shorter in the OS group than in the non-OS group (OS: 1.84 ± 1.85 vs. non-OS: 2.93 ± 2.43,
= 0.031). After adjusting the covariates, the OS group was associated with a significantly shorter period between surgery and menopause (
= 0.029). In conclusion, these results showed that a hysterectomy plus an OS might cause earlier menopause than a hysterectomy only. An OS should be preoperatively discussed with patients regarding the possibility of early menopause. The findings of this study require further large-scale investigations to reinforce the results.
Metasurfaces offer complete control of optical wavefront at the subwavelength scale, advancing a new class of artificial planar optics, including lenses, waveplates, and holograms, with unprecedented ...merits over conventional optical components. In particular, the ultrathin, flat, and compact characteristics of metasurfaces facilitate their integration with semiconductor devices for the development of miniaturized and multifunctional optoelectronic systems. In this work, generation of structured light is implemented at an ultracompact wafer‐level through the monolithic integration of metasurface with standard vertical cavity surface‐emitting lasers (VCSELs). This work opens new perspectives for the design of structured light systems with compactness, lightweight, and scalability. Ultracompact beam structured laser chips with versatile functionalities are experimentally demonstrated, including multichannel beams array generation, on‐chip large‐angle beam steering up to 60°, and wafer‐level holographic beam shaping with a wide field of view (about 124°). The results will promote the development of compact light structuring systems with great potential in 3D imaging, displays, robotic vision, human–computer interaction, and augmented/virtual reality.
On‐chip generation of structured light is demonstrated via monolithic integration of dielectric metasurfaces with standard vertical cavity surface‐emitting lasers (VCSELs). This new type of ultracompact beam structuring chip exhibits versatile functionalities, including multichannel beams array generation, on‐chip large‐angle beam steering up to 60°, and wafer‐level holographic beam shaping with a wide field of view.
Metasurface polarization optics that consist of 2D array of birefringent nano‐antennas have proven remarkable capabilities to generate and manipulate vectorial fields with subwavelength resolution ...and high efficiency. Integrating this new type of metasurface with the standard vertical cavity surface‐emitting laser (VCSEL) platform enables an ultracompact and powerful solution to control both phase and polarization properties of the laser on a chip, which allows to structure a VCSEL into vector beams with on‐demand wavefronts. Here, this concept is demonstrated by directly generating versatile vector beams from commercially available VCSELs through on‐chip integration of high‐index dielectric metasurfaces. Experimentally, the versatility of the approach for the development of vectorial VCSELs are validated by implementing a variety of functionalities, including directional emission of multibeam with specified polarizations, vectorial holographic display, and vector vortex beams generations. Notably, the proposed vectorial VCSELs integrated with a single layer of beam shaping metasurface bypass the requirements of multiple cascaded optical components, and thus have the potential to promote the advancements of ultracompact, lightweight, and scalable vector beams sources, enriching and expanding the applications of VCSELs in optical communications, laser manipulation and processing, information encryption, and quantum optics.
On‐chip generation and manipulation of vector beams are demonstrated by monolithically integrating vectorial metasurfaces with standard vertical cavity surface‐emitting lasers (VCSELs). The developed approach enables a powerful tool to structure the complex wavefronts of a VCSEL in an ultracompact way, providing the access to previously unattainable both phase and polarization degrees of freedom.
The gut microbiota-derived metabolite, trimethylamine N-oxide (TMAO) plays an important role in cardiovascular disease (CVD). The fasting plasma TMAO was shown as a prognostic indicator of CVD ...incident in patients and raised the interest of intervention targeting gut microbiota. Here we develop a clinically applicable method called oral carnitine challenge test (OCCT) for TMAO-related therapeutic drug efforts assessment and personalising dietary guidance.
A pharmacokinetic study was performed to verify the design of OCCT protocol. The OCCT was conducted in 23 vegetarians and 34 omnivores to validate gut microbiota TMAO production capacity. The OCCT survey was integrated with gut microbiome, host genotypes, dietary records and serum biochemistry. A humanised gnotobiotic mice study was performed for translational validation.
The OCCT showed better efficacy than fasting plasma TMAO to identify TMAO producer phenotype. The omnivores exhibited a 10-fold higher OR to be high TMAO producer than vegetarians. The TMAO-associated taxa found by OCCT in this study were consistent with previous animal studies. The TMAO producer phenotypes were also reproduced in humanised gnotobiotic mice model. Besides, we found the faecal
gene was not associated with TMAO production; therefore, other key relevant microbial genes might be involved. Finally, we demonstrated the urine TMAO exhibited a strong positive correlation with plasma TMAO (r=0.92, p<0.0001) and improved the feasibility of OCCT.
The OCCT can be used to identify TMAO-producer phenotype of gut microbiota and may serve as a personal guidance in CVD prevention and treatment.
NCT02838732; Results.
Heteroatom doped atomically dispersed Fe1‐NC catalysts have been found to show excellent activity toward oxygen reduction reaction (ORR). However, the origin of the enhanced activity is still ...controversial because the structure‐function relationship governing the enhancement remains elusive. Herein, sulfur(S)‐doped Fe1‐NC catalyst was obtained as a model, which displays a superior activity for ORR towards the traditional Fe‐NC materials. 57Fe Mössbauer spectroscopy and electron paramagnetic resonance spectroscopy revealed that incorporation of S in the second coordination sphere of Fe1‐NC can induce the transition of spin polarization configuration. Operando 57Fe Mössbauer spectra definitively identified the low spin single‐Fe3+‐atom of C‐FeN4‐S moiety as the active site for ORR. Moreover, DFT calculations unveiled that lower spin state of the Fe center after the S doping promotes OH* desorption process. This work elucidates the underlying mechanisms towards S doping for enhancing ORR activity, and paves a way to investigate the function of broader heteroatom doped Fe1‐NC catalysts to offer a general guideline for spin‐state‐determined ORR.
The enhanced oxygen reduction reaction (ORR) activity of sulfur‐doped Fe‐N‐C single‐atom catalysts is studied from Fe spin‐state tuning. Operando 57Fe Mössbauer spectra monitoring further supported the low‐spin (LS) single‐Fe3+‐atom of the C‐FeN4‐S moiety as the active site for the ORR.
Employing knowledge-based theory, this study builds upon social network theory and investigates the influence of knowledge networks on firms' innovation performance. This study incorporates the ...structural view of social networks and interorganizational interactions to develop the dimensions of knowledge networks, as well as to demonstrate the effects of firms' knowledge integration capability between knowledge networks and innovation performance. Investigating high-tech firms in Taiwan science parks, this study employs the social network research method to establish the boundaries of knowledge networks. The results show that each dimension of knowledge networks improves firms' innovation performance, and that firms' knowledge integration capability has a fully mediating effect on the relationship between knowledge cognition and innovation performance, but only a partial mediating effect on the relationships among firms' network centrality, knowledge heterogeneity, and innovation performance. Consequently, this study provides suggestions and comments for firms on how to engage in inter-organizational cooperative relationships.
Solid oxide fuel cells with proton conducting electrolytes (H–SOFCs) show great potential for more efficient energy conversion over their oxygen ionic conducting counterparts at temperatures below ...650 °C, providing a comparably high performance cathode material can be available. A brief review of current development of cathode materials shows that materials with triple (oxygen ionic, protonic, and electronic) conducting properties are most promising for H–SOFCs. In this work, a triple-conducting LiNi0.8Co0.2O2 (LNCO) with layered structure, allowing simultaneous conduction of intrinsic oxygen ion and electron as well as the extrinsic proton, is proposed as a cathode material for H–SOFC. The electrochemical impedance spectroscopy analysis of LNCO shows the good oxygen reduction reaction (ORR) activity with a considerably low activation energy of 0.88 eV, and an evident water uptake capability those facilitate the cathode reaction process. Fuel cells using LNCO cathode on a BaZr0.1Ce0.7Y0.2O3 proton-conducting electrolyte render a peak power density of 410 mW cm−2 at 650 °C under H2/air condition, which is higher than most of the typical cathode materials reported with similar cell configurations. This work also demonstrated a new series of simple and low cost cathode materials simultaneously possessing interesting triple-conduction and good ORR activities for low temperature H–SOFCs.
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•LiNi0.8Co0.2O2 (LNCO) shows typical layered structure by solid state reaction.•LNCO presents good ORR activity with low activation energy on BZCY electrolyte.•Proton conduction in LNCO is proven by EIS study in various moisture contents.•Fuel cell with LNCO cathode gives excellent performances, outperform typical cathodes.•A new series of cathode materials with similar structure is indicated.
To investigate the effectiveness of a school-based program promoting outdoor activities in Taiwan for myopia prevention and to identify protective light intensities.
Multi-area, cluster-randomized ...intervention controlled trial.
A total 693 grade 1 schoolchildren in 16 schools participated. Two hundred sixty-seven schoolchildren were in the intervention group and 426 were in the control group.
Initially, 24 schools were randomized into the intervention and control groups, but 5 and 3 schools in the intervention and control groups, respectively, withdrew before enrollment. A school-based Recess Outside Classroom Trial was implemented in the intervention group, in which schoolchildren were encouraged to go outdoors for up to 11 hours weekly. Data collection included eye examinations, cycloplegic refraction, noncontact axial length measurements, light meter recorders, diary logs, and questionnaires.
Change in spherical equivalent and axial length after 1 year and the intensity and duration of outdoor light exposures.
The intervention group showed significantly less myopic shift and axial elongation compared with the control group (0.35 diopter D vs. 0.47 D; 0.28 vs. 0.33 mm; P = 0.002 and P = 0.003) and a 54% lower risk of rapid myopia progression (odds ratio, 0.46; 95% confidence interval CI, 0.28-0.77; P = 0.003). The myopic protective effects were significant in both nonmyopic and myopic children compared with controls. Regarding spending outdoor time of at least 11 hours weekly with exposure to 1000 lux or more of light, the intervention group had significantly more participants compared with the control group (49.79% vs. 22.73%; P < 0.001). Schoolchildren with longer outdoor time in school (≥200 minutes) showed significantly less myopic shift (measured by light meters; ≥1000 lux: 0.14 D; 95% CI, 0.02-0.27; P = 0.02; ≥3000 lux: 0.16 D; 95% CI, 0.002-0.32; P = 0.048).
The school-based outdoor promotion program effectively reduced the myopia change in both nonmyopic and myopic children. Outdoor activities with strong sunlight exposure may not be necessary for myopia prevention. Relatively lower outdoor light intensity activity with longer time outdoors, such as in hallways or under trees, also can be considered.
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