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1.
Plant Physiol ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637315

RESUMEN

Seed deterioration during storage is a major problem in agricultural and forestry production and for germplasm conservation. Our previous studies have shown that a mitochondrial outer membrane protein VOLTAGE-DEPENDENT ANION CHANNEL (VDAC) is involved in programmed cell death (PCD)-like viability loss during the controlled deterioration treatment (CDT) of elm (Ulmus pumila L.) seeds, but its underlying mechanism remains unclear. In this study, we demonstrate that the oxidative modification of GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE (GAPDH) is functioned in the gate regulation of VDAC during the CDT of elm seeds. Through biochemical and cytological methods and observations of transgenic material [Arabidopsis (Arabidopsis thaliana), Nicotiana benthamiana, and yeast (Saccharomyces cerevisiae)], we demonstrate that cysteine S-glutathionylated UpGAPDH1 interacts with UpVDAC3 during seed aging, which leads to a mitochondrial permeability transition and aggravation of cell death, as indicated by the leakage of the mitochondrial pro-apoptotic factor cytochrome c and the emergence of apoptotic nucleus. Physiological assays and inductively coupled plasma mass spectrometry (ICP-MS) analysis revealed that GAPDH glutathionylation is mediated by increased glutathione, which might be caused by increases in the concentrations of free metals, especially Zn. Introduction of the Zn-specific chelator TPEN [(N, N, N', N'-Tetrakis (2-pyridylmethyl)ethylenediamine)] significantly delayed seed aging. We conclude that glutathionylated UpGAPDH1 interacts with UpVDAC3 and serves as a pro-apoptotic protein for VDAC-gating regulation and cell death initiation during seed aging.

2.
Chin J Traumatol ; 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38508908

RESUMEN

PURPOSE: To comprehensively analyze the geographic and temporal trends of foot fracture, understand its health burden by age, sex, and sociodemographic index (SDI), and explore its leading causes from 1990 to 2019. METHODS: The datasets in the present study were generated from the Global Burden of Diseases Study 2019, which included foot fracture data from 1990 to 2019. We extracted estimates along with the 95% uncertainty interval (UI) for the incidence and years lived with disability (YLDs) of foot fracture by location, age, gender, and cause. The epidemiology and burden of foot fracture at the global, regional, and national level was exhibited. Next, we presented the age and sex patterns of foot fracture. The leading cause of foot fracture was another focus of this study from the viewpoint of age, sex, and location. Then, Pearson's correlations between age-standardized rate (ASR), SDI, and estimated annual percentage change were calculated. RESULTS: The age-standardized incidence rate was 138.68 (95% UI: 104.88 - 182.53) per 100,000 persons for both sexes, 174.24 (95% UI: 134.35 - 222.49) per 100,000 persons for males, and 102.19 (95% UI: 73.28 - 138.00) per 100,000 persons for females in 2019. The age-standardized YLDs rate was 5.91 (95% UI: 3.58 - 9.25) per 100,000 persons for both genders, 7.35 (95% UI: 4.45 - 11.50) per 100,000 persons for males, and 4.51 (95% UI: 2.75 - 7.03) per 100,000 persons for females in 2019. The global incidence and YLDs of foot fracture increased in number and decreased in ASR from 1990 to 2019. The global geographical distribution of foot fracture is uneven. The incidence rate for males peaked at the age group of 20 - 24 years, while that for females increased with advancing age. The incidence rate of older people was rising, as younger age incidence rate declined from 1990 to 2019. Falls, exposure to mechanical forces, and road traffic injuries were the 3 leading causes of foot fracture. Correlations were observed between ASR, estimated annual percentage change, and SDI. CONCLUSIONS: The burden of foot fracture remains high globally, and it poses an enormous public health challenge, with population ageing. It is necessary to allocate more resources to the high-risk populations. Targeted realistic intervention policies and strategies are warranted.

3.
Arch Gynecol Obstet ; 309(5): 2167-2173, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38503849

RESUMEN

OBJECTIVE: The purpose of this study is to compare the clinical efficacy of oral dydrogesterone and micronized vaginal progesterone (MVP) gel during the first HRT-FET cycle. METHODS: A retrospective cohort study based on a total of 344 women undergoing their first HRT-FET cycles without Gonadotropin-Releasing Hormone agonist (GnRH-a) pretreatment was conducted. All the cycles were allocated to two groups in the reproductive medical center at the University of Hong Kong-Shenzhen Hospital. One group (n = 193) received oral dydrogesterone 30 mg/d before embryo transfer, while the other group (n = 151) received MVP gel 180 mg/d. RESULTS: The demographics and baseline characteristics of two groups were comparable. We found no statistically significant difference in live birth rate (24.35% vs. 31.13%, P = 0.16), clinical pregnancy rate (34.72% vs. 36.42%, P = 0.74), embryo implantation rate (25.09% vs. 28.36%, P = 0.43), positive pregnancy rate (42.49% vs 38.41%, P = 0.45), miscarriage rate (9.33% vs 3.97%, P = 0.05), or ectopic pregnancy rate (0.52% vs. 0.66%, P = 0.86) between the oral dydrogesterone group and MVP gel group. In the multivariate logistic regression analysis for covariates, medication used for luteal support was not associated with live birth rate (OR = 0.73, 95% CI: 0.32-1.57, P = 0.45). And the different luteal support medication did not have a significant positive association with the live birth rate in the cycles with day 2 embryo transferred (OR = 1.39, 95% CI:0.66-2.39, P = 0.39) and blastocyst transferred (OR = 1.31 95% CI:0.64-2.69, P = 0.46). CONCLUSION: 30 mg/d oral dydrogesterone and 180 mg/d MVP gel revealed similar reproductive outcomes in HRT-FET cycles in the study.


Asunto(s)
Didrogesterona , Progesterona , Embarazo , Femenino , Humanos , Progesterona/uso terapéutico , Estudios Retrospectivos , Índice de Embarazo , Transferencia de Embrión , Luteína
4.
Parasit Vectors ; 17(1): 111, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448975

RESUMEN

Toxoplasmosis is a zoonosis caused by Toxoplasma gondii (T. gondii). The current treatment for toxoplasmosis remains constrained due to the absence of pharmaceutical interventions. Thus, the pursuit of more efficient targets is of great importance. Lipid metabolism in T. gondii, including fatty acid metabolism, phospholipid metabolism, and neutral lipid metabolism, assumes a crucial function in T. gondii because those pathways are largely involved in the formation of the membranous structure and cellular processes such as division, invasion, egress, replication, and apoptosis. The inhibitors of T. gondii's lipid metabolism can directly lead to the disturbance of various lipid component levels and serious destruction of membrane structure, ultimately leading to the death of the parasites. In this review, the specific lipid metabolism pathways, correlative enzymes, and inhibitors of lipid metabolism of T. gondii are elaborated in detail to generate novel ideas for the development of anti-T. gondii drugs that target the parasites' lipid metabolism.


Asunto(s)
Toxoplasma , Toxoplasmosis , Animales , Metabolismo de los Lípidos , Apoptosis , Zoonosis , Toxoplasmosis/tratamiento farmacológico
5.
Angew Chem Int Ed Engl ; 63(11): e202400119, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38268159

RESUMEN

The water (H2 O) dissociation is critical for various H2 O-associated reactions, including water gas shift, hydrogen evolution reaction and hydrolysis corrosion. While the d-band center concept offers a catalyst design guideline for H2 O activation, it cannot be applied to intermetallic or main group elements-based systems because Coulomb interaction was not considered. Herein, using hydrolysis corrosion of Mg as an example, we illustrate the critical role of the dipole of the intermetallic catalysts for H2 O dissociation. The H2 O dissociation kinetics can be enhanced using Mgx Mey (Me=Co, Ni, Cu, Si and Al) as catalysts, and the hydrogen generation rate of Mg2 Ni-loaded Mg reached 80 times as high as Ni-loaded Mg. The adsorbed H2 O molecules strongly couple with the Mg-Me dipole of Mgx Mey , lowering the H2 O dissociation barrier. The dipole-based H2 O dissociation mechanism is applicable to non-transition metal-based systems, such as Mg2 Si and Mg17 Al12 , offering a flexible catalyst design strategy for controllable H2 O dissociation.

6.
Psychon Bull Rev ; 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38087065

RESUMEN

Retaining gaze in working memory (WM) is essential for successfully navigating through the social world. In the current study, we investigated how WM stores gaze direction by focusing on the role of face context in gaze WM. To address this question, we propose two competing hypotheses. The independence hypothesis predicts that eye gaze is stored independently and is not susceptible to the influence of the surrounding face context. Conversely, the embedding hypothesis claims that gaze WM involves face context and that disruption of holistic face processing would also impair memory for embedded gaze. In three experiments, we adopted different manipulations to disrupt holistic face processing and compared WM performance for gaze within and without face context. In Experiments 1 and 2, we tested WM for gaze direction with schematic upright or inverted faces. We found better performance for gaze within upright faces (vs. inverted faces) by increasing the probability of being remembered. In Experiment 3, we replaced schematic faces with photographic faces, and disrupted holistic processing by using scrambled faces. Results replicated our previous findings, showing that photographic gaze within intact faces was better remembered than gaze presented alone or gaze within scrambled faces. These findings indicate that gaze memory is face-dependent and support the embedding hypothesis.

7.
Lupus Sci Med ; 10(2)2023 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-38154829

RESUMEN

OBJECTIVE: This study aimed to investigate the clinical significance of exostosin 1 (EXT1) in confirmed and suspected lupus membranous nephropathy (LMN). METHODS: EXT1 was detected in 67 renal tissues of M-type phospholipase A2 receptor (PLA2R)-negative and ANA-positive membranous nephropathy by immunohistochemistry, and cases were divided into confirmed LMN and suspected LMN. The clinicopathological data were compared among the above groups, as well as EXT1-positive group and EXT1-negative group. RESULTS: Twenty-two cases (73.3%) of confirmed LMN and six cases (16.2%) of suspected LMN exhibited EXT1 expression on the glomerular basement membrane and/or mesangium area, showing a significant difference (p<0.001). Concurrently, lupus nephritis (LN) of pure class V demonstrated a lower frequency of EXT1 positivity compared with mixed class V LN in the confirmed LMN group (31.8% vs 68.2%, p=0.007). EXT1-positive patients in the confirmed and suspected LMN group showed significant differences in some clinicopathological data comparing with EXT1-negative patients (p<0.05). Follow-up data revealed that a greater proportion of patients in the EXT1-positive group achieved complete remission post-treatment (p<0.05). Cox regression analysis showed that EXT1 positivity was significantly correlated with complete remission across the entire study cohort (HR 5.647; 95% CI, 1.323 to 12.048; p=0.019). Kaplan-Meier analysis indicated that the EXT1-positive group had a higher rate of accumulated nephrotic remission compared with the EXT1-negative group in the whole study cohort (p=0.028). CONCLUSIONS: The EXT1-positive group exhibited a higher active index and a more favourable renal outcome than the EXT1-negative group. It would be better to recognise suspected LMN with EXT1 positivity as a potential autoimmune disease and maintain close follow-up due to its similarities with confirmed LMN.


Asunto(s)
Glomerulonefritis Membranosa , Lupus Eritematoso Sistémico , Nefritis Lúpica , Humanos , Relevancia Clínica , Glomerulonefritis Membranosa/diagnóstico , Glomerulonefritis Membranosa/tratamiento farmacológico , Riñón/patología , Nefritis Lúpica/diagnóstico , Nefritis Lúpica/patología
8.
IEEE Int Conf Rehabil Robot ; 2023: 1-6, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37941198

RESUMEN

Accurate real-time estimation of the gait phase (GP) is crucial for many control methods in exoskeletons and prostheses. A class of approaches to GP estimation construct the phase portrait of a segment or joint angle, and use the normalized polar angle of this diagram to estimate the GP. Although several studies have investigated such methods, quantitative information regarding their performance is sparse. In this work, we assess the performance of 3 portrait-based methods in flat and inclined steady walking conditions, using quantitative metrics of accuracy, repeatability and linearity. Two methods use portraits of the hip angle versus angular velocity (AVP), and hip angle versus integral of the angle (IAP). In a novel third method, a linear transformation is applied to the portrait to improve its circularity (CSP). An independent heel-strike (HS) detection algorithm is employed in all algorithms, rather than assuming HSs to occur at a constant point on the portrait. The novel method shows improvements in all metrics, notably significant root-mean-square error reductions compared to IAP (-3%, p < 0.001) and AVP (-2.4%, p < 0.001) in slope, and AVP (-1.61%, p = 0.0015) in flat walking. A non-negligible inter-subject variability is observed between phase angles at HS (equivalent to up to 8.4% of error in the GP), highlighting the importance of explicit HS detection for portrait-based methods.


Asunto(s)
Marcha , Caminata , Humanos , Talón , Algoritmos , Fenómenos Biomecánicos
9.
IEEE Int Conf Rehabil Robot ; 2023: 1-6, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37941275

RESUMEN

The growing demand for online gait phase (GP) estimation, driven by advancements in exoskeletons and prostheses, has prompted numerous approaches in the literature. Some approaches explicitly use time, while others rely on state variables to estimate the GP. In this article, we study two novel GP estimation methods: a State-based Method (SM) which employs the phase portrait of the hip angle (similar to previous methods), but uses a stretching transformation to reduce the nonlinearity of the estimated GP; and a Time-based Method (TM) that utilizes feature recognition on the hip angle signal to update the estimated cadence twice per gait cycle. The methods were tested across various speeds and slopes, encompassing steady and transient walking conditions. The results demonstrated the ability of both methods to estimate the GP in a range of conditions. The TM outperformed the SM, exhibiting a root-mean-squared error below 3% compared to 8.5% for the SM. However, the TM exhibited diminished performance during speed transitions, whereas the SM performed consistently in steady and transient conditions. The SM displayed a better performance in inclined walking and demonstrated higher linearity at faster speeds. Through the assessment of these methods in diverse conditions, this study lays the groundwork for further advancements in GP estimation methods and their application in assistive controllers.


Asunto(s)
Dispositivo Exoesqueleto , Humanos , Fenómenos Biomecánicos , Marcha , Caminata
10.
Science ; 382(6674): 1056-1065, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38033072

RESUMEN

The development of functionally distinct catalysts for enantioselective synthesis is a prominent yet challenging goal of synthetic chemistry. In this work, we report a family of chiral N-heterocyclic carbene (NHC)-ligated boryl radicals as catalysts that enable catalytic asymmetric radical cycloisomerization reactions. The radical catalysts can be generated from easily prepared NHC-borane complexes, and the broad availability of the chiral NHC component provides substantial benefits for stereochemical control. Mechanistic studies support a catalytic cycle comprising a sequence of boryl radical addition, hydrogen atom transfer, cyclization, and elimination of the boryl radical catalyst, wherein the chiral NHC subunit determines the enantioselectivity of the radical cyclization. This catalysis allows asymmetric construction of valuable chiral heterocyclic products from simple starting materials.

12.
Front Psychol ; 14: 1190620, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37881218

RESUMEN

The increasing need for human-robot interaction requires not only robots to understand how humans think, but also humans to understand robots. Interestingly, little attention has been given to how humans interpret robots' behaviors. In this study, we adopted a social mental rotation task and investigated whether socially engaging behaviors could influence how people take a robot's perspectives. In a real lab, two android robots with neutral appearance sat opposite each other by a table with conflicting perspectives. Before the participant started the experiment, one of the robots behaved more interactively than the other by showing more socially engaging behaviors. Then the participant was required to identify rotated normal or mirrored digits presented inbetween the two robots. Results revealed a significant interactive effect between the digits type (normal; mirrored) and robot type (interactive; noninteractive). When digits were oriented to the interactive robot, we found a larger RT difference between normal and mirrored digits. In general, these findings suggested that robots' interactive behaviors could influence how people spontaneously consider the robot's perspective. Future studies may further consider how interactive behaviors can shape human-robot relationships and facilitate human-robot interaction.

13.
Phys Rev Lett ; 131(14): 140801, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37862656

RESUMEN

Complementarity is an essential feature of quantum mechanics. The preparation of an eigenstate of one observable implies complete randomness in its complementary observable. In quantum cryptography, complementarity allows us to formulate security analyses in terms of phase-error correction. However, the concept becomes much subtler in the device-independent regime that offers security without device characterization. Security proofs of device-independent quantum cryptography tasks are often complex and quite different from those of their more standard device-dependent cousins. The existing proofs pose huge challenges to experiments, among which large data-size requirement is a crux. Here, we show the complementarity security origin of the device-independent tasks. By linking complementarity with quantum nonlocality, we recast the device-independent scheme into a quantum error correction protocol. Going beyond the identical-and-independent-distribution case, we consider the most general attack. We generalize the sample entropy in classical Shannon theory for the finite-size analysis. Our method exhibits good finite-size performance and brings the device-independent scheme to a more practical regime. Applying it to the data in a recent ion-trap-based device-independent quantum key distribution experiment, one could reduce the requirement on data size to less than a third. Furthermore, the operational meaning of complementarity naturally extends device-independent scenarios to advantage key distillation, easing experiments by tolerating higher loss and lower transmittance.

14.
Nat Commun ; 14(1): 6373, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37821432

RESUMEN

The tunability of reaction pathways is required for exploring efficient and low cost catalysts for ammonia synthesis. There is an obstacle by the limitations arising from scaling relation for this purpose. Here, we demonstrate that the alkali earth imides (AeNH) combined with transition metal (TM = Fe, Co and Ni) catalysts can overcome this difficulty by utilizing functionalities arising from concerted role of active defects on the support surface and loaded transition metals. These catalysts enable ammonia production through multiple reaction pathways. The reaction rate of Co/SrNH is as high as 1686.7 mmol·gCo-1·h-1 and the TOFs reaches above 500 h-1 at 400 °C and 0.9 MPa, outperforming other reported Co-based catalysts as well as the benchmark Cs-Ru/MgO catalyst and industrial wüstite-based Fe catalyst under the same reaction conditions. Experimental and theoretical results show that the synergistic effect of nitrogen affinity of 3d TMs and in-situ formed NH2- vacancy of alkali earth imides regulate the reaction pathways of the ammonia production, resulting in distinct catalytic performance different from 3d TMs. It was thus demonstrated that the appropriate combination of metal and support is essential for controlling the reaction pathway and realizing highly active and low cost catalysts for ammonia synthesis.

15.
Sci Adv ; 9(38): eadh9104, 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37738353

RESUMEN

Topological materials have received much attention because of their robust topological surface states, which can be potentially applied in electronics and catalysis. Here, we show that the topological insulator bismuth selenide functions as an efficient catalyst for the oxidative carbonylation of amines with carbon monoxide and dioxygen to synthesize urea derivatives. For example, the carbonylation of butylamine can be completed over bismuth selenide nanoparticle catalyst in 4 hours at 20°C with a yield of 99%, whereas most noble metal-based catalysts do not function at such a low temperature. Density functional theory calculations further reveal that the topological surface states facilitate the activation of dioxygen through a triplet-to-singlet spin-conversion reaction, in which active oxygen species are formed with a barrier of 0.4 electron volts for the subsequent reactions with amine and carbon monoxide.

16.
BMC Pregnancy Childbirth ; 23(1): 641, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37674133

RESUMEN

BACKGROUND: Preimplantation genetic testing for aneuploidy (PGT-A) was demonstrated to be superior to conventional IVF in reducing the incidence of miscarriage and abnormal offspring after the first embryo transfer (ET). PGT-A requires several embryo trophectoderm cells, but its negative impacts on embryo development and long-term influence on the health conditions of conceived children have always been a concern. As an alternative, noninvasive PGT-A (niPGT-A) approaches using spent blastocyst culture medium (SBCM) achieved comparable accuracy with PGT-A in several pilot studies. The main objective of this study is to determine whether noninvasive embryo viability testing (niEVT) results in better clinical outcomes than conventional IVF after the first embryo transfer. Furthermore, we further investigated whether niEVT results in higher the live birth rate between women with advanced maternal age (AMA, > 35 years old) and young women or among patients for whom different fertilization protocols are adopted. METHODS: This study will be a double-blind, multicenter, randomized controlled trial (RCT) studying patients of different ages (20-43 years) undergoing different fertilization protocols (in vitro fertilization [IVF] or intracytoplasmic sperm injection [ICSI]). We will enroll 1140 patients at eight reproductive medical centers over 24 months. Eligible patients should have at least two good-quality blastocysts (better than grade 4 CB). The primary outcome will be the live birth rate of the first embryo transfer (ET). Secondary outcomes will include the clinical pregnancy rate, ongoing pregnancy rate, miscarriage rate, cumulative live birth rate, ectopic pregnancy rate, and time to pregnancy. DISCUSSION: In this study, patients who undergo noninvasive embryo viability testing (niEVT) will be compared to women treated by conventional IVF. We will determine the effects on the pregnancy rate, miscarriage rate, and live birth rate and adverse events. We will also investigate whether there is any difference in clinical outcomes among patients with different ages and fertilization protocols (IVF/ICSI). This trial will provide clinical evidence of the effect of noninvasive embryo viability testing on the clinical outcomes of the first embryo transfer. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR) Identifier: ChiCTR2100051408. 9 September 2021.


Asunto(s)
Aborto Espontáneo , Tasa de Natalidad , Niño , Femenino , Embarazo , Humanos , Adulto , Aborto Espontáneo/epidemiología , Aborto Espontáneo/etiología , Inyecciones de Esperma Intracitoplasmáticas , Índice de Embarazo , Aneuploidia , Fertilización In Vitro , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
17.
Dalton Trans ; 52(42): 15484-15488, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37526930

RESUMEN

Wide application of novel materials often requires low-cost preparation methods. In this study, we present a simplified and facile preparation method for the [Ca24Al28O64]4+(e-)4 electride material (C12A7:e-). Successful preparation of the C12A7:e- electride was confirmed by XRD patterns and magnetic behavior analysis. The concentration of electrons in the prepared C12A7:e- powder was calculated to be approximately 2.23 × 1021 cm-3, as evaluated by iodometry and TPD. DFT calculations provided insight into the unique electronic structure of C12A7:e-. Additionally, the substitution of the Ca reductant with CaH2 led to a reduction in the solid-state reaction temperature from 1100 to 950 °C, which can be attributed to thermodynamic effects such as a reduction in ΔG°.

18.
Opt Lett ; 48(15): 4105-4108, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37527129

RESUMEN

We discuss the appearance of the Pancharatnam-Berry phase in polarization holography, and confirm the possibility of generating scalar vortex beams by using the Pancharatnam-Berry phase. The polarization holograms used to generate scalar vortex beams are produced in phenanthrenequinone-doped polymethylmethacrylate (PQ/PMMA), where each radial direction consists of an equivalent half-wave plate hologram with gradually changing directions. The spin angular momentum carried by a circular polarization reading wave is converted into orbital angular momentum in a reconstruction process, resulting in the formation of scalar vortex beams with positive and negative topological charges controlled by the reading polarization.

19.
J Org Chem ; 88(16): 11924-11934, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37560787

RESUMEN

A new method for the synthesis of α-amino phenylpropanoids under blue light-emitting diode irradiation has been developed through α-C-H benzylation of readily available N-phenyl glycine ester with benzyl oxalates as a coupling partner under mild conditions. A range of N-phenyl glycine esters were successfully converted to α-amino phenylpropanoid products in moderate to good yields. The utility of this methodology is underlined by its application to the late-state modification of natural products.

20.
Opt Lett ; 48(11): 2941-2944, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37262249

RESUMEN

We propose a simple and inexpensive method for the fabrication of polarization splitters with designable separation angles and a controllable active area, based on polarization holography of tensor theory. First, we design two polarization holograms that reconstruct waves with only p- or s-polarization components, respectively. Then, after we recorded these two holograms on the same position of the recording material using the interference approach, as a result, a polarization splitter could readily be prepared. The separation angles of fabricated polarization splitters can be easily adjusted by changing the interference angle, and the active area can also be easily modified by changing the sizes of the interference beams and recording material during the recording process. The experimental results verify the reliability and accuracy of this method. We believe that this work may broaden the application field of polarization holography.

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