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1.
Health Econ ; 33(1): 12-20, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37858318

RESUMO

Using representative data from China, we examine the causal effects of parental retirement on the health of adult children. To do so, we adopt a fuzzy regression discontinuity design and exploit the mandatory retirement ages in China as cut-off points. We find no evidence that parental retirement has significant effects on the mental health, healthcare utilization, or risky health behaviors of adult children. However, paternal retirement and maternal retirement have different effects on adult children's Self-reported health (SRH). Paternal retirement has a significantly negative effect only on the SRH of sons, while maternal retirement does not induce such effects. Potential mechanisms of intergenerational transfer through which parental retirement might affect adult children's health are also explored.


Assuntos
Saúde da Criança , Aposentadoria , Adulto , Criança , Humanos , Aposentadoria/psicologia , Pais/psicologia , Saúde Mental , China/epidemiologia
2.
Int J Mol Sci ; 25(18)2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39337634

RESUMO

Leymus chinensis, a halophytic perennial grass belonging to the Poaceae family, thrives in saline-alkali grasslands and harbors a rich repository of resistance-related genetic resources. This study focused on deciphering the stress-responsive mechanisms of L. chinensis by conducting transcriptomic sequencing under NaHCO3 stress, which resulted in the annotation of a segment corresponding to the 51WRKY gene. The alkali-induced gene LcWRKY40 (QIG37591) was identified by phylogenetic analysis. Real-time quantitative PCR analysis was performed on L. chinensis plants subjected to PEG6000 and alkaline salt (NaHCO3) stress, and the results indicated that the LcWRKY40 gene was upregulated in both the leaves and roots. The localization of the LcWRKY40 protein was confirmed by the use of green fluorescent protein (GFP) fusion technology in transformed rice protoplast cells. The GAL4-driven transformation of the LcWRKY40 gene in INVScI yeast cells, which exhibited enhanced tolerance upon overexpression of the LcWRKY40 gene under mannitol and alkaline salt (NaHCO3) stress conditions. Under drought stress using mannitol, the fresh weight of Nicotiana tabacum overexpressing the LcWRKY40 gene was significantly higher than that of wild-type(WT) tobacco. Through drought and salt alkali stress, we found that overexpressed tobacco at different stages always outperformed the wild type in terms of fresh weight, SOD, MDA, and Fv/Fm. This study provides preliminary insights into the involvement of the LcWRKY40 gene in responding to drought and alkaline salt stresses, highlighting its role in enhancing plant resistance to drought and saline-alkaline conditions. These findings lay the foundation for future molecular breeding strategies aimed at improving grass resistance from different aspects.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Nicotiana , Proteínas de Plantas , Tolerância ao Sal , Estresse Fisiológico , Nicotiana/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Tolerância ao Sal/genética , Filogenia , Plantas Geneticamente Modificadas/genética , Bicarbonato de Sódio/farmacologia , Poaceae/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Plantas Tolerantes a Sal/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo
3.
Opt Express ; 31(19): 30562-30569, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710596

RESUMO

Multi-gigahertz ultrafast fiber lasers are critical for many significant applications, including bioimaging, optical communications, and laser frequency combs. The gain fiber which is expected to simultaneously satisfy large mode-field area, highly gain coefficient and resistance to photodarkening, will effectively protect mode-locked materials/devices that generally possesses low damage threshold (<10 mJ/cm2) and enhance stability in the centimeter-scale fiber lasers. However, the gain fiber still remains a significant challenge. In this study, multi-element Er-Yb: silica glass fibers with large mode-field area are fabricated. Benefiting from the multi-element design, normalized frequency V-parameter of the silica glass fiber with a core diameter of around 10 µm is <2.405. Using the large mode-field area fibers, ultrafast fiber lasers with 1.6 GHz fundamental repetition rate are proposed and demonstrated. The signal-to-noise rate of the radio-frequency signal reaching up to 90 dB and the long-term stability are realized. The results indicated the fabricated large mode-field area fibers are demonstrated to be ultrafast fiber lasers with short resonant cavities, which could be extended to other rare-earth glass fiber device for exploration of high-power amplification systems.

4.
BMC Musculoskelet Disord ; 23(1): 637, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35787266

RESUMO

BACKGROUND: Given the unremitting growth in the volume of failed fixations of proximal femoral fractures (PFFs) in recent years, it is predictable that total hip replacements (THRs) will be the preferred surgical procedure. The long-term survival of cemented THR (CTHR) revisions remains controversial in patients aged 30-60 years. The goal of this retrospective review was to evaluate the 10-year survival of CTHRs following prior failed primary fixations of PFFs in patients aged 30-60 years. METHODS: We retrospectively identified CTHR revisions implemented at four medical centres during 2008-2017 for a failed primary fixation of PFFs in consecutive patients aged 30-60 years. The primary endpoint was implant survival calculated using the Kaplan-Meier method with 95% confidence intervals (CIs); secondary endpoints included functional scores assessed by Harris hip scores (HHS) and main revision-related orthopaedic complications. Follow-up was executed at 1, 2, 3, and 8 years following revision and then at 1-year intervals until the revision, death, or study deadline, whichever occurred first. RESULTS: In total, 120 patients (120 hips) who met the eligibility criteria were eligible for follow-up. The median follow-up was 10.2 years (range, 8-12 years). Kaplan-Meier survivorship showed that implant survival with revision for any reason as the endpoint was 95% at 5 years (CI: 93-97%), 89% at 8 years (CI: 86-92%), and 86% at 10 years (CI: 83-89%). Patients treated with three hollow screws had better revision-free survival than patients treated with proximal femoral nail antirotation (PFNA), dynamic hip screw (DHS) or titanium plate plus screws (three p < 0.05). Functional scores were apt to decrease gradually, and at the final follow-up, the mean HHS was 76.9 (range, 67.4-86.4). The overall rate of main revision-related orthopaedic complications was 18.3% (22/120). CONCLUSION: CTHR implemented following prior failed primary fixations of PFFs tends to afford an acceptable 10-year survival, along with advantageous HHS and a low rate of main revision-related orthopaedic complications, which may support an inclination to follow the utilisation of CTHRs, especially in revision settings for intracapsular fractures.


Assuntos
Artroplastia de Quadril , Fraturas do Fêmur , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Fraturas do Fêmur/etiologia , Seguimentos , Humanos , Reoperação , Estudos Retrospectivos
5.
BMC Nephrol ; 22(1): 350, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34706660

RESUMO

BACKGROUND: Intravenous iron sucrose is becoming a prevailing treatment for individuals undergoing maintenance haemodialysis, but comparisons of dosing regimens are lacking. The aim of this retrospective review was to evaluate the safety and efficacy of proactively administered high-dose iron sucrose versus reactively administered low-dose iron sucrose in patients undergoing maintenance haemodialysis. METHODS: We analysed the data of 1500 individuals with maintenance haemodialysis who were treated with either high-dose iron sucrose that was proactively administered (Group HD) or low-dose iron sucrose that was reactively administered (Group LD) at the First Affiliated Hospital of Chongqing Medical University from Jan 1, 2008, to Dec 31, 2020. The primary endpoints were the cumulative doses of iron and erythropoiesis-stimulating agent; the secondary endpoints were the events of nonfatal myocardial infarction, nonfatal stroke, hospitalization for heart failure, infection rate, and death from any cause. RESULTS: Of the 2124 individuals, 624 individuals were excluded because they met one or more of the exclusion criteria, thus resulting in 1500 individuals who were eligible for inclusion in the study (Group HD, n = 760 and Group LD, n = 740). The median follow-up for the two cohorts was 32 months (range: 25-36). A significant median difference was detected in the monthly iron dose between the groups (1121 mg [range: 800-1274] in the HD group vs. 366 mg [range: 310-690] in the LD group; p < 0.05). The median dose of an erythropoiesis-stimulating agent was 26,323 IU/month (range: 17,596-44,712) in the HD group and 37,934 IU/month (range: 22,402-59,380) in the LD group (median difference: - 7901 IU/month; 95% CI: - 9632--5013; p = 0.000). A significant difference was detected in the secondary endpoints (266 events in 320 cases in the HD group vs. 344 events in 385 cases in the LD group) (HR: 0.62; 95% CI: 0.51-0.79; p < 0.001). A significant difference was not observed in death from any cause (HR: 0.57; 95% CI: 0.48-1.00; p = 0.361). CONCLUSIONS: For individuals undergoing maintenance haemodialysis, high-dose iron sucrose that was proactively administered may be superior to low-dose iron sucrose that was reactively administered with low doses of erythropoiesis-stimulating agent.


Assuntos
Óxido de Ferro Sacarado/administração & dosagem , Hematínicos/administração & dosagem , Diálise Renal , Adulto , Idoso , Feminino , Óxido de Ferro Sacarado/efeitos adversos , Hematínicos/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
6.
Fish Shellfish Immunol ; 98: 10-18, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31911287

RESUMO

Two in vitro trials were conducted to identify a peptide with antioxidant activity and immunoenhancement from cottonseed meal protein hydrolysate (CPH) for fish. Primary hepatocytes of Megalobrama amblycephala were treated with CPH. In experiment 1, CPH significantly increased aspartate aminotransferase (GOT), alanine aminotransferase (GPT), total superoxide dismutase (t-SOD), catalase (CAT), and lysozyme activities, as well as up-regulated SOD, CAT, antimicrobial peptides 1 (Leap 1) and Leap 2 mRNA levels (p < 0.05). However, CPH significantly down-regulated the expression of NADPH oxidase-2 (NOX2), Kelch-like-ECH-associated protein 1 (Keap1), NF-E2-related factor 2 (Nrf2) and BTB and CNC homolog 1 (Bach1) mRNA (p < 0.05) in fish hepatocytes. Experiment 2 showed that the molecular mass of CPH was distributed mainly in the 700-1024 Da range. Peptide 1 (P1) and P2 significantly decreased GOT and GPT activities in conditioned medium (p < 0.05); however, P4 and P6 did not affect GOT and GPT activities (p > 0.05). Furthermore, P4 significantly increased hepatocyte GOT, GPT, t-SOD, CAT levels and lysozyme activities (p < 0.05), up-regulated SOD, CAT, Leap1 and Leap2 mRNA expression levels, and down-regulated the expression of Nrf2 and NOX2 mRNA (p < 0.05) in fish hepatocytes. The above results indicated that CPH and P4 enhanced hepatocyte metabolism, as well as improved antioxidant capacities and innate immunity of blunt snout bream hepatocytes.


Assuntos
Antioxidantes/metabolismo , Cyprinidae/imunologia , Imunidade Inata/efeitos dos fármacos , Hidrolisados de Proteína/metabolismo , Ração Animal/análise , Animais , Óleo de Sementes de Algodão/química , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Hidrolisados de Proteína/administração & dosagem , Distribuição Aleatória
7.
Opt Express ; 27(8): 10438-10448, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31052903

RESUMO

Fundamental repetition rates of 3.1 GHz, 7.0 GHz, and 12.5 GHz in passively modelocked Yb-doped fiber lasers are demonstrated. To the best of our knowledge, the fundamental repetition rate of 12.5 GHz is the highest value for 1.0 µm mode-locked fiber lasers. The mode-locked oscillator has a peak wavelength of 1047.5 nm and a pulse duration of 1.9 ps. The repetition rate signal has a signal-to-noise ratio of 57 dB. The peak wavelength of mode-locked spectra gradually makes a blue-shift and the modelocked threshold power increases with an increase in pulse repetition rate. Furthermore, in contrast to most of the all-normal-dispersion mode-locked fiber lasers, the present linear resonator (e.g., length < 1 cm) allows the buildup of gain-guided soliton without any filter effect. To unveil the underlying pulse shaping mechanism, a combined model comprising dynamic rate equations and the generalized nonlinear Schrödinger equation is established. Surprisingly, an essential gain filtering effect, which is contributed by a 26-nm gain bandwidth, is revealed and can verify the gain-guided pulse dynamics. Moreover, the pulse build-up in temporal and frequency domain, like spectral evolution and gain bandwidths, is numerically carried out in detail.

8.
Opt Lett ; 44(24): 6001-6004, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32628205

RESUMO

High-power femtosecond (fs)-pulsed all-fiber lasers operating at high repetition rates are highly demanded for various applications, including laser micromachining, nonlinear optical imaging, high-speed optical sampling, arbitrary waveform generation, and frequency metrology. However, their performance has long been limited by either the average power, repetition rate, pulse width, or compactness, which prevent practical applications. In this work, we report a high repetition rate fs-pulsed all-fiber laser at 2.0 µm that so far provides the best performance metrics, to the best of our knowledge, i.e., ∼2GHz fundamental repetition rate, 126 fs pulse width, ∼8W average power, and all-fiber configuration. We anticipate that this laser can be a promising fs-pulsed fiber laser source for applications requiring a GHz repetition rate.

9.
Fish Shellfish Immunol ; 84: 100-107, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30267755

RESUMO

An 8-week feeding trial was carried out under controlled condition to evaluate the effect of dietary fructooligosaccharide (FOS) on growth performance, whole body composition, antioxidant status and immunity of crabs fed high levels of plant protein diets. Thus, six experimental diets were formulated (designated as F0P50, F0P60, F0P70, F0.2P50, F0.2P60 and F0.2P70), which contain two FOS levels (0 or 0.2%) and three plant protein levels (50, 60, or 70%) according to a 2 × 3 factorial design. The results showed that weight gain increased significantly as dietary plant protein level decreased from 70% to 50%. At 50% plant protein level, the addition of 0.2% FOS can significantly elevate weight gain (WG) (P < 0.05). The highest value in survival rate was observed in crabs fed F0.2P50 and F0.2P60 diet. Crabs fed F0.2P50 diet showed significantly higher crude protein content (P < 0.05) compared with those in other groups, but there were no significant differences in the contents of moisture, crude lipid and ash among all groups (P > 0.05). Catalase (CAT) activity in crabs fed F0.2P50 increased significantly (P < 0.05) compared with crabs fed F0P60, F0P70, F0.2P60 and F0.2P70, but malondialdehyde (MDA) concentrations decreased significantly (P < 0.05). Meanwhile, nitric oxide (NO) concentration, acid phosphatase (ACP) and alkaline phosphatase (AKP) activities of crabs fed 0.2% FOS diets increased significantly (P < 0.05) compared with crabs fed 0% FOS diets. The expressions of prophenoloxidase (propo) was significantly (P < 0.05) affected only by dietary plant protein levels with the highest values observed in 50% plant protein diet, whereas the opposite was true for Myeloid differentiation factor 88 (myd88). The mRNA expressions of mitochondrial manganese superoxide dismutase (mtmnsod), lipopolysaccharide-induced TNF-α factor (litaf) and toll like receptors (tlrs) were significantly affected (P < 0.05) by both FOS and plant protein levels. The cytosolic manganese superoxide dismutase (cytmnsod) mRNA expressions in F0.2P50 and F0.2P60 groups were significantly higher than those in F0P70 and F0.2P70 groups. The results in this study indicated that supplementation with 0.2% FOS can enhance growth performance in crabs fed lower plant protein diets and as well improve immunity in those fed with higher plant protein diets.


Assuntos
Braquiúros/efeitos dos fármacos , Oligossacarídeos/administração & dosagem , Proteínas de Vegetais Comestíveis/administração & dosagem , Animais , Braquiúros/crescimento & desenvolvimento , Braquiúros/imunologia , Suplementos Nutricionais
10.
Opt Express ; 26(13): 16411-16421, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30119473

RESUMO

Multi-gigahertz fundamental repetition rate, tunable repetition rate and wavelength, ultrafast fiber lasers at wavelengths of 1.0, 1.5, and 2.0 µm are experimentally demonstrated and summarized. At the wavelength of 1.0 µm, the laser wavelength is tuned in the range of 1040.1-1042.9 nm and the repetition rate is shifted by 226 kHz in a 3-cm-long all-fiber laser by controlling the temperature of the resonator. Compared with a previous work where the maximum average power was 0.8 mW, the power in this study is significantly improved to 57 mW under a launched pump power of 213 mW, thus achieving an optical-to-optical efficiency of 27%. For comparison, a similar temperature-tuning technique is implemented in a Tm3+-doped ultrafast oscillator but, as expected, it results in a broader tunable range of 14.1 nm (1974.1-1988.2 nm) in wavelength as compared with the value of 1.8 nm for the wavelength of 1.0 µm. The repetition rate in the process is shifted by 294 kHz. For the high-frequency range from 100 kHz to 10 MHz, the value of integrated timing jitter gradually increases with an increase in temperature. Finally, to the best of our knowledge, for the first time, a new method for tuning wavelength and repetition rate is proposed and demonstrated for a femtosecond fiber laser at the wavelength of 1.5 µm. Through fine rotation of the alignment angle between the Er/Yb:glass fiber and a semiconductor saturable absorption mirror, the peak wavelength can be tuned in the range of 1591.4-1586.1 nm and the repetition rate is shifted by 60 kHz.

11.
Opt Express ; 26(13): 17458, 2018 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-30119557

RESUMO

We present the erratum regarding the x-axis label in two figures, a numerical correction and a mathematical symbol correction.

12.
Opt Express ; 26(8): 10842-10857, 2018 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-29716015

RESUMO

States that are switchable from single soliton to pulse bunch in a compact semiconductor saturable absorber mirror (SESAM) mode-locked fiber laser with a fundamental repetition rate of 3.2 GHz are experimentally investigated and further studied via simulations. A composite filtering effect comprising an intracavity low-finesse Fabry-Perot (FP) filter, an artificial optical low-pass filter, and a gain filter implements the state switching to pulse bunch. A numerical model is proposed to clarify the mechanism underlying the switching. It reveals that, for pulse interval ∆T > τA (relaxation time of the SESAM) in a pulse bunch, the laser operates in pulse-bound build up. In an inverse mechanism the state returns to single soliton, in which the ∆T is obtained from the free spectral range Ωc of the intracavity FP filter by mechanically controlling the distance between the SESAM and gain fiber. This pulse bunch regime of operation ought to be amenable to a quasi-steady-state treatment. It represents an alternative emergence trait in the temporal domain between a main soliton with strong sidelobes in both sides and a bound soliton pair with weak sub-sidelobes. Another profile of the pulse bunch state is that the side peak amplitude in the autocorrelation trace is more than 50%, which is distinct and larger than that in the conventional bound state regime in fiber lasers. The optical spectra, radio frequency spectra, and frequency chirp are further analyzed. These numerical results agree well with the experimental ones within the variation range of the crucial values of Ωc and enable the explicit understanding of such behavior in SESAM mode-locked high-repetition-rate fiber lasers.

13.
Opt Lett ; 43(1): 42-45, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29328192

RESUMO

The Earth's magnetic field has significant effects that protect us from cosmic radiation and provide navigation for biological migration. However, slow temporal variations originating in the liquid outer core invariably exist. To understand the working mechanism of the geomagnetic field and improve accuracy of navigation systems, a high-precision magnetometer is essential to measure the absolute magnetic field. A helium optically pumping magnetometer is an advanced approach, but its sensitivity and accuracy are directly limited by the low-frequency relative intensity noise and frequency stability characteristics of a light source. Here, we demonstrate a near quantum-noise limited and absolute frequency stabilized 1083 nm single-frequency fiber laser. The relative intensity noise is only 5 dB higher than the quantum-noise limit, and the root mean square of frequency fluctuation is ∼17 kHz after locked. This fiber laser could suppress the fluctuation of magnetic resonant frequency and improve the signal-to-noise ratio of the magnetic resonance signal detection.

14.
Opt Express ; 25(22): 27646-27651, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29092235

RESUMO

A passively mode-locked Yb3+-doped fiber laser with a fundamental repetition rate of 5 GHz and wavelength tunable performance is demonstrated. A piece of heavily Yb3+-doped phosphate fiber with a high net gain coefficient of 5.7 dB/cm, in conjunction with a fiber mirror by directly coating the SiO2/Ta2O5 dielectric films on a fiber ferrule is exploited for shortening the laser cavity to 2 cm. The mode-locked oscillator has a peak wavelength of 1058.7 nm, pulse duration of 2.6 ps, and the repetition rate signal has a high signal-to-noise ratio of 90 dB. Moreover, the wavelength of the oscillator is found to be continuously tuned from 1056.7 to 1060.9 nm by increasing the temperature of the laser cavity. Simultaneously, the repetition rate correspondingly decreases from 4.945874 to 4.945496 GHz. Furthermore, the long-term stability of the mode-locked operation in the ultrashort laser cavity is realized by exploiting temperature controls. This is, to the best of our knowledge, the highest fundamental pulse repetition rate for 1-µm mode-locked fiber lasers.

15.
Opt Express ; 25(12): 13324-13331, 2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28788868

RESUMO

An all-fiber high-power and broad-frequency-band near-shot-noise-limited kHz-linewidth (Δν ~1.7 kHz) single-frequency master-oscillator power amplifier (MOPA) laser at 1.5 µm is demonstrated. To significantly suppress the intensity noise of seed laser and mitigate the detrimental effects of amplified spontaneous emission and stimulated Brillouin scattering in fiber amplifiers, more than 23 W of a stable low noise single-frequency laser output is achieved with a relative intensity noise of < -150 dB/Hz @0.5 mW (near to the shot-noise limit: -152.9 dB/Hz) in the frequency band from 0.1 to 50 MHz. It is believed that the achieved laser performance of ultra-low intensity noise and high-power output make the laser source become a promising candidate in further applications, such as cold atom optical lattice, quantum key distribution, and gravitational wave detection.

16.
Opt Express ; 25(17): 19752-19759, 2017 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-29041663

RESUMO

A kHz-order linewidth controllable 1550 nm single-frequency fiber laser (SFFL) is demonstrated for the first time to our best knowledge. The control of the linewidth is realized by using a low-pass filtered white Gaussian noise (WGN) signal applied on a fiber stretcher in an optical feedback loop. Utilizing WGN signals with different signal amplitudes An and different cutoff frequencies fc, the linewidths are availably controlled in a wide range from 0.8 to 353 kHz. The obtained optical signal-to-noise ratio (OSNR) is more than 72.0 dB, and the relative intensity noise (RIN) at frequency greater than 40 MHz reaches -148.5 dB/Hz which approaches the shot noise limit (-152.9 dB/Hz). This kHz-order linewidth controllable SFFL is meaningful and valuable, for optimizing the receiver sensitivity and bit error rate (BER) performance of the coherent optical communication system based on high-order quadrature amplitude modulation (QAM).

17.
Plant J ; 83(2): 312-25, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26043144

RESUMO

Several studies have described quantitative trait loci (QTL) for seed size in wheat, but the relevant genes and molecular mechanisms remain largely unknown. Here we report the functional characterization of the wheat TaCYP78A3 gene and its effect on seed size. TaCYP78A3 encoded wheat cytochrome P450 CYP78A3, and was specifically expressed in wheat reproductive organs. TaCYP78A3 activity was positively correlated with the final seed size. Its silencing caused a reduction of cell number in the seed coat, resulting in an 11% decrease in wheat seed size, whereas TaCYP78A3 over-expression induced production of more cells in the seed coat, leading to an 11-48% increase in Arabidopsis seed size. In addition, the cell number in the final seed coat was determined by the TaCYP78A3 expression level, which affected the extent of integument cell proliferation in the developing ovule and seed. Unfortunately, TaCYP78A3 over-expression in Arabidopsis caused a reduced seed set due to an ovule developmental defect. Moreover, TaCYP78A3 over-expression affected embryo development by promoting embryo integument cell proliferation during seed development, which also ultimately affected the final seed size in Arabidopsis. In summary, our results indicated that TaCYP78A3 plays critical roles in influencing seed size by affecting the extent of integument cell proliferation. The present study provides direct evidence that TaCYP78A3 affects seed size in wheat, and contributes to an understanding of the cellular basis of the gene influencing seed development.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Sementes , Triticum/enzimologia , Proliferação de Células/genética , Inativação Gênica , Dados de Sequência Molecular , Filogenia , Locos de Características Quantitativas , Triticum/embriologia , Triticum/genética
18.
Dev Biol ; 387(1): 64-72, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24394376

RESUMO

Defects of the ventral body wall are prevalent birth anomalies marked by deficiencies in body wall closure, hypoplasia of the abdominal musculature and multiple malformations across a gamut of organs. However, the mechanisms underlying ventral body wall defects remain elusive. Here, we investigated the role of Wnt signaling in ventral body wall development by inactivating Wls or ß-catenin in murine abdominal ectoderm. The loss of Wls in the ventral epithelium, which blocks the secretion of Wnt proteins, resulted in dysgenesis of ventral musculature and genito-urinary tract during embryonic development. Molecular analyses revealed that the dermis and myogenic differentiation in the underlying mesenchymal progenitor cells was perturbed by the loss of ectodermal Wls. The activity of the Wnt-Pitx2 axis was impaired in the ventral mesenchyme of the mutant body wall, which partially accounted for the defects in ventral musculature formation. In contrast, epithelial depletion of ß-catenin or Wnt5a did not resemble the body wall defects in the ectodermal Wls mutant. These findings indicate that ectodermal Wnt signaling instructs the underlying mesodermal specification and abdominal musculature formation during ventral body wall development, adding evidence to the theory that ectoderm-mesenchyme signaling is a potential unifying mechanism for the origin of ventral body wall defects.


Assuntos
Abdome/embriologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Desenvolvimento Muscular/genética , Receptores Acoplados a Proteínas G/fisiologia , Via de Sinalização Wnt/genética , beta Catenina/fisiologia , Abdome/crescimento & desenvolvimento , Animais , Padronização Corporal/genética , Diferenciação Celular/genética , Ectoderma/embriologia , Ectoderma/crescimento & desenvolvimento , Ectoderma/metabolismo , Embrião de Mamíferos/embriologia , Embrião de Mamíferos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mesoderma/embriologia , Mesoderma/crescimento & desenvolvimento , Mesoderma/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Acoplados a Proteínas G/genética , Fatores de Transcrição/genética , Sistema Urogenital/embriologia , Sistema Urogenital/crescimento & desenvolvimento , Proteínas Wnt/deficiência , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteína Wnt-5a , beta Catenina/genética , Proteína Homeobox PITX2
19.
Appl Opt ; 53(5): 892-7, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24663268

RESUMO

We demonstrate the self-mode-locking operation of a thulium (Tm)-doped fiber laser (TDFL) with a simple linear cavity. Since the laser cavity does not include any specific mode-locker, we experimentally investigate and analyze the self-mode-locking mechanism. The mode-locking operation is attributed to the combination of the self-phase modulation effect and the weak saturable absorption of the high-concentration Tm-doped fiber. The mode-locked TDFL operates at a central wavelength of 1985.5 nm with the 3 dB spectral linewidth of 0.18 nm. The self-mode-locking generates a large pulse energy of 32.7 nJ with a pulsed repetition rate of 2.05 MHz and is stable with a radio-frequency signal-to-noise ratio of more than 54 dB. To the best of our knowledge, it is the first demonstration of a 2 µm Tm-doped fiber laser mode-locked by such technique.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Lasers , Ressonância de Plasmônio de Superfície/instrumentação , Túlio/química , Transferência de Energia , Desenho de Equipamento , Análise de Falha de Equipamento
20.
Innov Aging ; 8(9): igae074, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39350943

RESUMO

Background and Objectives: Recent research has explored the spillover effects of retirement on spousal well-being, yet limited attention has been given to the short-term impact on spousal disability. This study explored the asymmetric spillover impact of retirement on spouses' disability severity among a national cohort of urban residents in China. Research Design and Methods: Utilizing 4 waves of data (2011-2018) from the China Health and Retirement Longitudinal Survey, we employ a nonparametric regression discontinuity design to estimate the short-term effect of retirement on spousal disability severity. Disability is assessed based on their ability to perform activities of daily living (ADLs) and instrumental activities of daily living (IADLs). Furthermore, we conduct heterogeneity analysis stratified by factors such as the husband's retirement status, health conditions, lifestyle behaviors, and the wife's educational level. Additionally, we explore potential mechanisms including changes in health behaviors, emotions, and disease diagnoses. Results: Our findings indicate that wives' retirement has a significant favorable short-term effect on husbands' ADL scores, with a magnitude of -0.644 points (-9.78% relative to baseline). A significant beneficial effect of wives' retirement on the prevalence of husbands' difficulty in dressing, bathing, and eating was observed with substantial magnitudes of 0.075, 0.201, and 0.051 points, respectively. Various heterogeneity analyses and sensitivity tests confirmed the robustness of our results. The positive spillover effect of wives' retirement likely results from reduced negative emotions in husbands. In contrast, husbands' retirement does not affect the prevalence of ADL/IADL disability in their wives. Discussion and Implications: Underscoring the gender asymmetry in the effects of spousal retirement on disability, this study emphasizes the need for tailored policies considering men's and women's distinct disability experiences.

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