Reported here is the development of a class of chiral spirosilabiindane scaffolds by Rh‐catalyzed asymmetric double hydrosilation, for the first time. Enantiopure SPSiOL (spirosilabiindane diol), a ...new type of chiral building block for the preparation of various chiral ligands and catalysts, was readily prepared on greater than 10 gram scale using this protocol. The potential of this new spirosilabiindane scaffold in asymmetric catalysis was preliminarily demonstrated by development of the corresponding monodentate phosphoramidite ligands (SPSiPhos), which were used in both a Rh‐catalyzed hydrogenation and a Pd‐catalyzed intramolecular carboamination.
Designer scaffolds: Reported here is the rational design, asymmetric synthesis, and application of chiral spirosilabiindane scaffolds. Highly enantioselective synthesis of spirosilabiindanes is demonstrated for the first time by using a Rh‐catalyzed double hydrosilation. The versatility of this new chiral scaffold was demonstrated by the gram‐scale synthesis of SPSiOL, and application of its phosphoramidite derivatives as ligands in asymmetric catalysis.
We present a concrete realization of the sound speed resonance (SSR) mechanism for primordial black hole (PBH) formation within a specific model of Dirac-Born-Infeld (DBI) inflation. We perform a ...perturbative approach to phenomenologically construct such a viable DBI inflation model that involves the nonoscillating stage and the oscillating stage, with a type of specific forms of the warp factor and the potential. We show that the continuous but nonsmooth conjunction of sound speed between two stages does not yield manifest effects on the phenomenology of SSR, and thus, our model gives rise to the same PBH mass spectrum as the original predictions of SSR. Additionally, we also demonstrate that the violation of adiabaticity of the Mukhanov-Sasaki equation does not affect the comoving curvature perturbation after Hubble crossing in the nonresonant region. Making use of observational data, we derive various cosmological constraints on the parameter space. Our analyses show that the predicted tensor-to-scalar ratio is typically small, while the amplitude of primordial non-Gaussianity can meet with cosmic microwave background bounds, and additionally, the consistency relation for single-field slow-roll inflation is softly violated in our case due to the small sound speed variations.
The risk factors, pathological mechanisms and therapeutic strategies of sexual dysfunction.
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Sexual dysfunction (SD) is a disorder of sexual behavior and sexual sensation that appears ...as an abnormality or absence of sexual psychology and physiological reaction. It is a general term for many different symptoms includes several aspects, erectile dysfunction (ED), failure of sexual intercourse and loss of libido/desire. According to statistics, 52% of 40˜70 year old men suffer from varying degrees of SD. And these diseases caused by a variety of biological and psychological factors. In world about 15% of couples are affected by sexual disharmony among these 40 to 50% are because of male factors. Considering the sensitivity of male reproduction system, it is being easily affected by multiple risk factors, such as chronic diseases, environmental contaminants, drug toxicity and unhealthy lifestyle and so on. In the last few years, significant progress have been made toward understanding the various forms of male SD and the possible potential pathological mechanisms. However, for the time being, the exact cause of SD is not fully understood from the literature. What is also significant about there are quite limited treatments in reproductive medicine being directed against these lesions. The purpose of this review is to summarize the current findings of pathogenic factors of SD in clinical or animal studies, to elaborate the underlying mechanisms of these diseases from studies in vivo and in vitro, to analyses the risk factors, and to describe the management strategies traditionally recommended of male sexual dysfunction. The review findings elucidate a systematic strategies for effectively preventing these diseases.
Despite the great demand on and attempts at package express shipping services, online retailers have not yet had a practical solution to make such services profitable. In this paper, we propose an ...economical approach to express package delivery, i.e., exploiting relays of taxis with passengers to help transport package collectively, without degrading the quality of passenger services. Specifically, we propose a two-phase framework called crowddeliver for the package delivery path planning. In the first phase, we mine the historical taxi trajectory data offline to identify the shortest package delivery paths with estimated travel time given any Origin-Destination pairs. Using the paths and travel time as the reference, in the second phase we develop an online adaptive taxi scheduling algorithm to find the near-optimal delivery paths iteratively upon real-time requests and direct the package routing accordingly. Finally, we evaluate the two-phase framework using the real-world data sets, which consist of a point of interest, a road network, and the large-scale trajectory data, respectively, that are generated by 7614 taxis in a month in the city of Hangzhou, China. Results show that over 85% of packages can be delivered within 8 hours, with around 4.2 relays of taxis on average.
Brazing, as a common method of bonding ceramic and metal, has been applied in microelectronics, aerospace, machinery and other domains extensively. The residual thermal stress in the brazed joint has ...direct effects on the mechanical properties of the joint, so how to control the generation of residual thermal stress has become the vital point. In this paper, the methods of reducing residual thermal stress in the brazing process in recent years are reviewed. The generation and effects of residual thermal stress in the brazed joint are introduced. Besides, the methods of detecting residual thermal stress are discussed, and different methods of reducing residual thermal stress in brazed joints are also analyzed. Finally, the future development directions of reducing residual thermal stress in the brazed joint are proposed.
Abstract
Terahertz (THz) waves show great potential in nondestructive testing, biodetection and cancer imaging. Despite recent progress in THz wave near-field probes/apertures enabling raster ...scanning of an object’s surface, an efficient, nonscanning, noninvasive, deep subdiffraction imaging technique remains challenging. Here, we demonstrate THz near-field microscopy using a reconfigurable spintronic THz emitter array (STEA) based on the computational ghost imaging principle. By illuminating an object with the reconfigurable STEA followed by computing the correlation, we can reconstruct an image of the object with deep subdiffraction resolution. By applying an external magnetic field, in-line polarization rotation of the THz wave is realized, making the fused image contrast polarization-free. Time-of-flight (TOF) measurements of coherent THz pulses further enable objects at different distances or depths to be resolved. The demonstrated ghost spintronic THz-emitter-array microscope (GHOSTEAM) is a radically novel imaging tool for THz near-field imaging, opening paradigm-shifting opportunities for nonintrusive label-free bioimaging in a broadband frequency range from 0.1 to 30 THz (namely, 3.3–1000 cm
−1
).
Abstract
Context
We characterized linear growth in infants and children with X-linked hypophosphatemia (XLH).
Objective
Provide linear growth curves for children with XLH from birth to early ...adolescence.
Design
Data from 4 prior studies of XLH were pooled to construct growth curves. UX023-CL002 was an observational, retrospective chart review. Pretreatment data were collected from 3 interventional trials: two phase 2 trials (UX023-CL201, UX023-CL205) and a phase 3 trial (UX023-CL301).
Setting
Medical centers with expertise in treating XLH.
Patients
Children with XLH, 1-14 years of age.
Intervention
None.
Main Outcome Measure
Height-for-age linear growth curves, including values for the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles for children with XLH compared to population norms.
Results
A total of 228 patients (132 girls, 96 boys) with 2381 height measurements were included. Nearly all subjects (> 99%) reported prior management with supplementation therapy. Compared to the Center for Disease Control and Prevention growth curves, boys at age 3 months, 6 months, 9 months, 1 year, and 2 years had median height percentiles of 46%, 37%, 26%, 18%, and 5%, respectively; for girls the median height percentiles were 52%, 37%, 25%, 18%, and 7%, respectively. Annual growth in children with XLH fell below that of healthy children near 1 year of age and progressively declined during early childhood, with all median height percentiles < 8% between 2 and 12 years old.
Conclusion
Children with XLH show decreased height gain by 1 year of age and remain below population norms thereafter. These data will help evaluate therapeutic interventions on linear growth for pediatric XLH.
Aims
The aim of the present meta‐analysis was to evaluate the efficacy and safety of fingolimod in patients with relapsing multiple sclerosis (RMS).
Methods
PubMed, Embase, the Cochrane Library and ...ClinicalTrials.gov were searched for relevant studies. Two authors independently selected the studies, assessed the risk of bias, and extracted the data. The meta‐analysis was performed in RevMan 5.3 provided by the Cochrane Collaboration.
Results
Ten studies met the inclusion criteria. In patients with RMS, fingolimod demonstrated a significantly lower annualized relapse rate (0.5 mg/d: mean difference 95% confidence interval = −0.22 −0.29 to −0.14; 1.25 mg/d: −0.26 −0.36 to −0.16; 5 mg/d: −0.41 −0.72 to −0.10) than placebo. Fingolimod also exhibited a favorable performance on other magnetic resonance imaging outcomes and improved the quality of life in patients. No significant difference was noted in the prevalence of adverse events between the fingolimod treatment group and the placebo/disease‐modifying therapy groups.
Conclusions
Fingolimod may offer benefits for RMS patients and presents an acceptable safety profile.
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