The chiral keto-substituted propargylamines are an essential class of multifunctional compounds in the field of organic and pharmaceutical synthesis and have attracted considerable attention, but the ...related synthetic approaches remain limited. Therefore, a concise and efficient method for the enantioselective synthesis of β-keto propargylamines
chiral phosphoric acid-catalyzed asymmetric Mannich reaction between β-keto acids and
-alkynyl
-Boc
,
-acetals as easily available
-alkynyl imine precursors has been demonstrated here, affording a broad scope of β-keto
-Boc-propargylamines in high yields (up to 97%) with generally high enantioselectivities (up to 97 : 3 er).
Prolonging the ovarian lifespan is attractive and challenging. An optimal clinical strategy must be safe, long‐acting, simple, and economical. Allotransplantation of brown adipose tissue (BAT), which ...is most abundant and robust in infants, has been utilized to treat various mouse models of human disease. Could we use BAT to prolong the ovarian lifespan of aging mice? Could we try BAT xenotransplantation to alleviate the clinical need for allogeneic BAT due to the lack of voluntary infant donors? In the current study, we found that a single rat‐to‐mouse (RTM) BAT xenotransplantation did not cause systemic immune rejection but did significantly increase the fertility of mice and was effective for more than 5 months (equivalent to 10 years in humans). Next, we did a series of analysis including follicle counting; AMH level; estrous cycle; mTOR activity; GDF9, BMP15, LHR, Sirt1, and Cyp19a level; ROS and annexin V level; IL6 and adiponectin level; biochemical blood indices; body temperature; transcriptome; and DNA methylation studies. From these, we proposed that rat BAT xenotransplantation rescued multiple indices indicative of follicle and oocyte quality; rat BAT also improved the metabolism and general health of the aging mice; and transcriptional and epigenetic (DNA methylation) improvement in F0 mice could benefit F1 mice; and multiple KEGG pathways and GO classified biological processes the differentially expressed genes (DEGs) or differentially methylated regions (DMRs) involved were identical between F0 and F1. This study could be a helpful reference for clinical BAT xenotransplantation from close human relatives to the woman.
Prolonging ovarian lifespan is attracting and challenging. Herein, we found that one-time rat-to-mouse BAT xenotransplantation did not cause serious global rejection reaction, while significantly prolonged the ovarian lifespan and improved the overall health condition of aging mice. Mechanical studies revealed that the number of antral follicles, which will conduce to live birth, increased onefold through a combined improvement at epigenetic, transcriptional, and protein level.
Development of a thinner, wideband electromagnetic absorbing material that aims to address the growing electromagnetic pollution has becoming a hot topic. Herein, a heterojunction material consisting ...with 2-dimensional g-C3N4 and hierarchical flower shaped ZnO has been produced by a simple method, which exhibits the superior dielectric response ability. In details, the formed heterojunction with crossed energy structure benefits to the conductivity loss ability. Moreover, the as-prepared g-C3N4/ZnO with controlled interfaces possess the desirable interfacial polarization relaxation behavior, which may additional contribution for the dielectric loss. Owing to the improved conductive loss an interface polarization, the ultimately sample has a broad band EM absorption ability, with an effective absorption region of 5.3GHz under a thin matched thickness of 1.5mm. The method for designing of heterojunction-based material can be desirable candidate for the high-performance EM absorber.
•The fabricated g-C3N4/ZnO exhibits the crossed energy band structure, promoting the microwave dielectric response ability.•The controllable interface between g-C3N4 and ZnO can be easier designed and induced the dielectric polarization relaxation behavior.•3) The effective absorption frequency bandwidth could up to 5.3GHz while the thickness was only 1.5mm.
Abstract
The minimum variation timescale (MVT) of soft gamma-ray repeaters can be an important probe to estimate the emission region in pulsar-like models, as well as the Lorentz factor and radius of ...the possible relativistic jet in gamma-ray burst (GRB)–like models, thus revealing their progenitors and physical mechanisms. In this work, we systematically study the MVTs of hundreds of X-ray bursts (XRBs) from SGR J1935+2154 observed by Insight-HXMT, GECAM, and Fermi/Gamma-ray Burst Monitor from 2014 July to 2022 January through the Bayesian block algorithm. We find that the MVTs peak at ∼2 ms, corresponding to a light-travel time size of about 600 km, which supports the magnetospheric origin in pulsar-like models. The shock radius and the Lorentz factor of the jet are also constrained in GRB-like models. Interestingly, the MVT of the XRB associated with FRB 200428 is ∼70 ms, which is longer than that of most bursts and implies its special radiation mechanism. In addition, the median of MVTs is 7 ms, shorter than the median MVTs of 40 ms and 480 ms for short GRBs or long GRBs, respectively. However, the MVT is independent of duration, similar to GRBs. Finally, we investigate the energy dependence of MVT and suggest that there is a marginal evidence for a power-law relationship like GRBs, but the rate of variation is at least about an order of magnitude smaller. These features may provide an approach to identify bursts with a magnetar origin.
Bladder-related pain symptoms in patients with bladder pain syndrome/interstitial cystitis (BPS/IC) are often accompanied by depression and memory deficits. Magnesium deficiency contributes to ...neuroinflammation and is associated with pain, depression, and memory deficits. Neuroinflammation is involved in the mechanical allodynia of cyclophosphamide (CYP)-induced cystitis. Magnesium-L-Threonate (L-TAMS) supplementation can attenuate neuroinflammation. This study aimed to determine whether and how L-TAMS influences mechanical allodynia and accompanying depressive symptoms and memory deficits in CYP-induced cystitis.
Injection of CYP (50 mg/kg, intraperitoneally, every 3 days for 3 doses) was used to establish a rat model of BPS/IC. L-TAMS was administered in drinking water (604 mg·kg
·day
). Mechanical allodynia in the lower abdomen was assessed with von Frey filaments using the up-down method. Forced swim test (FST) and sucrose preference test (SPT) were used to measure depressive-like behaviors. Novel object recognition test (NORT) was used to detect short-term memory function. Concentrations of Mg
in serum and cerebrospinal fluid (CSF) were measured by calmagite chronometry. Western blot and immunofluorescence staining measured the expression of tumor necrosis factor-α/nuclear factor-κB (TNF-α/NF-κB), interleukin-1β (IL-1β), and N-methyl-D-aspartate receptor type 2B subunit (NR2B) of the N-methyl-D-aspartate receptor in the L6-S1 spinal dorsal horn (SDH) and hippocampus.
Free Mg
was reduced in the serum and CSF of the CYP-induced cystitis rats on days 8, 12, and 20 after the first CYP injection. Magnesium deficiency in the serum and CSF correlated with the mechanical withdrawal threshold, depressive-like behaviors, and short-term memory deficits (STMD). Oral application of L-TAMS prevented magnesium deficiency and attenuated mechanical allodynia (n = 14) and normalized depressive-like behaviors (n = 10) and STMD (n = 10). The upregulation of TNF-α/NF-κB signaling and IL-1β in the L6-S1 SDH or hippocampus was reversed by L-TAMS. The change in NR2B expression in the SDH and hippocampus in the cystitis model was normalized by L-TAMS.
Normalization of magnesium deficiency by L-TAMS attenuated mechanical allodynia, depressive-like behaviors, and STMD in the CYP-induced cystitis model via inhibition of TNF-α/NF-κВ signaling and normalization of NR2B expression. Our study provides evidence that L-TAMS may have therapeutic value for treating pain and comorbid depression or memory deficits in BPS/IC patients.
•Few studies have explored the associations between Cl-PFESAs and serum lipids.•A large population-based study was conducted in China to assess these associations.•Perfluorooctane sulfonate ...alternatives were adversely associated with serum lipids.•That such associations were similar to those between legacy PFASs and TC.
Chlorinated polyfluorinated ether sulfonic acids (Cl-PFESAs), a group of perfluorooctane sulfonate (PFOS) alternatives, can be widely observed in humans and environmental matrices. However, associations between exposure to Cl-PFESAs and serum lipid levels in adults are unknown.
To explore the relationships between Cl-PFESA levels and serum lipid levels in adults.
We analyzed 1238 adults from the Isomers of C8 Health Project, a cross-sectional study conducted in China from July 2015 to October 2016. The average age of the participants was 61.98 ± 14.40 years. We quantified two select legacy per- and perfluoroalkyl substances perfluorooctanoic acid (PFOA) and PFOS and their alternatives (6:2 and 8:2 Cl-PFESAs). We also measured four serum lipids: low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), total cholesterol (TC), and triglycerides (TG). We used generalized linear models to estimate the associations between PFASs and serum lipids, with PFASs defined as either a categorical variable divided into quartiles or as a continuous variable.
We found that 6:2 Cl-PFESA was positively associated with serum TC and LDL-C. For instance, LDL-C levels in the highest quartile of 6:2 Cl-PFESA exposure (Q4) were significantly higher than those in the lowest quartile (Q1) β: 0.19, 95% confidence interval (CI): 0.08, 0.30. Further analysis showed that one ln-ng/mL increase in 6:2 Cl-PFESA exposure corresponded to a 0.10 mmol/L (95% CI: 0.05, 0.16) LDL-C increase, and that exposure to 8:2 Cl-PFESA was negatively correlated with HDL-C (β: −0.03, 95% CI: −0.05, −0.01). TC had a similar relationship with both 6:2 Cl-PFESA and legacy PFASs. Participants with a BMI ≥ 25 kg/m2 exhibited a stronger association between 6:2 Cl-PFESA and TC.
Our findings make the novel suggestion that exposure to Cl-PFESAs are adversely associated with serum lipid levels, and that such associations are also observed in legacy PFASs. Increased investigation into the effects of Cl-PFESAs exposure on human health is warranted.
Cyclists can be easily exposed to traffic-related pollutants due to riding on or close to the road during commuting in cities. PM2.5 has been identified as one of the major pollutants emitted by ...vehicles and associated with cardiopulmonary and respiratory diseases. As routing has been suggested to reduce the exposures for cyclists, in this study, PM2.5 was monitored with low-cost sensors during commuting periods to develop models for identifying low exposure routes in three Asian cities: Taipei, Osaka, and Seoul. The models for mapping the PM2.5 in the cities were developed by employing the random forest algorithm in a two-stage modeling approach. The land use features to explain spatial variation of PM2.5 were obtained from the open-source land use database, OpenStreetMap. The total length of the monitoring routes ranged from 101.36 to 148.22 km and the average PM2.5 ranged from 13.51 to 15.40 μg/m³ among the cities. The two-stage models had the standard k-fold cross-validation (CV) R2 of 0.93, 0.74, and 0.84 in Taipei, Osaka, and Seoul, respectively. To address spatial autocorrelation, a spatial cross-validation approach applying a distance restriction of 100 m between the model training and testing data was employed. The over-optimistic estimates on the predictions were thus prevented, showing model CV-R2 of 0.91, 0.67, and 0.78 respectively in Taipei, Osaka, and Seoul. The comparisons between the shortest-distance and lowest-exposure routes showed that the largest percentage of reduced averaged PM2.5 exposure could reach 32.1% with the distance increases by 37.8%. Given the findings in this study, routing behavior should be encouraged. With the daily commuting trips expanded, the cumulative effect may become significant on the chronic exposures over time. Therefore, a route planning tool for reducing the exposures shall be developed and promoted to the public.
Display omitted
•Cyclists' PM2.5 exposures were monitored in Taipei, Osaka, and Seoul.•Random forest land use models are developed for mapping PM2.5.•Spatial k-fold cross-validation is applied, showing model CV-R2 above 0.67.•Alternative routes can reduce the PM2.5 exposure over 30% for cyclist commuters.
The photocatalytic technique is an attractive strategy to activate persulfate for generating free radicals in the wastewater purification process. Herein, CdS nanoparticles with unique optical ...properties were employed to decorate the COF-based photocatalyst (denoted as TpMA) containing C
3
N
4
active units
via
a feasible method. Interestingly, TpMA decorated with CdS nanoparticles exhibited enhanced optical absorbability and a small charge transfer resistance. Benefitting from the close interfacial connections between CdS nanoparticles and TpMA, the recombination of photogenerated electrons and holes could be effectively inhibited. As expected, the obtained CdS@TpMA composites displayed excellent photocatalytic activity, which could activate persulfate to produce SO
4
−
&z.rad; and &z.rad;OH under visible light irradiation. In comparison with pristine CdS nanoparticles and TpMA, the 25% CdS@TpMA composite presented the best photocatalytic degradation ability, and 97.6% of diclofenac sodium, 95.2% of tetracycline and 93.8% of ibuprofen could be effectively removed within 70 min. The corresponding TOC removal efficiencies were more than 60%. More significantly, the 25% CdS@TpMA composite displayed great performance and structural stabilities. Furthermore, a possible photocatalytic mechanism was also proposed. In short, the current work not only provides a promising candidate for degrading drug residues, but also offers some novel viewpoints for further research.
COF-based photocatalysts containing C
3
N
4
units decorated with CdS were constructed and employed as the mediator of peroxydisulfate activation for removing pollutants.
The pentagonal bipyramidal single-ion magnets (SIMs) are among the most attractive prototypes of high-performance single-molecule magnets (SMMs). Here, a fluorescence-active phosphine oxide ligand ...CyPh
PO (=cyclohexyl(diphenyl)phosphine oxide) was introduced into Dy(CyPh
PO)
(H
O)
Br
⋅2 (CyPh
PO)⋅EtOH⋅3 H
O, and combined dynamic magnetic measurement, optical characterization, ab initio calculation, and magneto-optical correlation of this high-performance pseudo-D
Dy
SIM with large U
(508(2) K) and high magnetic hysteresis temperature (19 K) were performed. This work provides a deeper insight into the rational design of promising molecular magnets.
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