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The reciprocal coordination between cholesterol absorption in the intestine and de novo cholesterol synthesis in the liver is essential for maintaining cholesterol homeostasis, yet the mechanisms governing the opposing regulation of these processes remain poorly understood. Here, we identify a hormone, Cholesin, which is capable of inhibiting cholesterol synthesis in the liver, leading to a reduction in circulating cholesterol levels. Cholesin is encoded by a gene with a previously unknown function (C7orf50 in humans; 3110082I17Rik in mice). It is secreted from the intestine in response to cholesterol absorption and binds to GPR146, an orphan G-protein-coupled receptor, exerting antagonistic downstream effects by inhibiting PKA signaling and thereby suppressing SREBP2-controlled cholesterol synthesis in the liver. Therefore, our results demonstrate that the Cholesin-GPR146 axis mediates the inhibitory effect of intestinal cholesterol absorption on hepatic cholesterol synthesis. This discovered hormone, Cholesin, holds promise as an effective agent in combating hypercholesterolemia and atherosclerosis.
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Colesterol , Hormonas , Proteínas de Unión al ARN , Animales , Humanos , Ratones , Colesterol/metabolismo , Hormonas/genética , Hormonas/metabolismo , Hipercolesterolemia/metabolismo , Hígado/metabolismo , Transducción de Señal , Proteínas de Unión al ARN/metabolismoRESUMEN
Increasing planting density is a key strategy for enhancing maize yields1-3. An ideotype for dense planting requires a 'smart canopy' with leaf angles at different canopy layers differentially optimized to maximize light interception and photosynthesis4-6, among other features. Here we identified leaf angle architecture of smart canopy 1 (lac1), a natural mutant with upright upper leaves, less erect middle leaves and relatively flat lower leaves. lac1 has improved photosynthetic capacity and attenuated responses to shade under dense planting. lac1 encodes a brassinosteroid C-22 hydroxylase that predominantly regulates upper leaf angle. Phytochrome A photoreceptors accumulate in shade and interact with the transcription factor RAVL1 to promote its degradation via the 26S proteasome, thereby inhibiting activation of lac1 by RAVL1 and decreasing brassinosteroid levels. This ultimately decreases upper leaf angle in dense fields. Large-scale field trials demonstrate that lac1 boosts maize yields under high planting densities. To quickly introduce lac1 into breeding germplasm, we transformed a haploid inducer and recovered homozygous lac1 edits from 20 diverse inbred lines. The tested doubled haploids uniformly acquired smart-canopy-like plant architecture. We provide an important target and an accelerated strategy for developing high-density-tolerant cultivars, with lac1 serving as a genetic chassis for further engineering of a smart canopy in maize.
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Producción de Cultivos , Fotosíntesis , Hojas de la Planta , Zea mays , Brasinoesteroides/metabolismo , Producción de Cultivos/métodos , Oscuridad , Haploidia , Homocigoto , Luz , Mutación , Fotosíntesis/efectos de la radiación , Fitocromo A/metabolismo , Fitomejoramiento , Hojas de la Planta/anatomía & histología , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Hojas de la Planta/efectos de la radiación , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Factores de Transcripción/metabolismo , Zea mays/anatomía & histología , Zea mays/enzimología , Zea mays/genética , Zea mays/crecimiento & desarrollo , Zea mays/efectos de la radiaciónRESUMEN
We demonstrated a two-dimensional vector displacement (bending) sensor with high angular resolution based on Vernier effect generated by two cascaded Fabry-Perot interferometers (FPI) in a seven-core fiber (SCF). To form the FPI, plane-shaped refractive index modulations are fabricated as the reflection mirrors in the SCF using slit-beam shaping and femtosecond laser direct writing. Three pairs of cascaded FPIs are fabricated in the center core and the two non-diagonal edge cores of the SCF and applied to the vector displacement measurement. The proposed sensor exhibits high displacement sensitivity with significant direction dependence. The magnitude and direction of the fiber displacement can be obtained via monitoring the wavelength shifts. Moreover, the source fluctuations and the temperature cross-sensitivity can be referenced out by monitoring the bending-insensitive FPI of the center core.
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We propose and fabricate a high-sensitivity vector vibration accelerometer with a multicore fiber Bragg grating Fabry-Perot (FBG-FP) structure. The acceleration sensitivities of the FBG and FBG-FP are 0.15 and 1.26 V/g, respectively. After packaging, the acceleration sensitivity of the FBG-FP is further improved to 6.89 V/g, which is 45.9 times higher than that of the FBG. The resonant frequency of the accelerometer increases from 30 to 86 Hz. Both the sensitivity and resonant frequency of the accelerometer are improved. Owing to the asymmetry of the outer core of the multicore fiber, high-sensitivity two-dimensional vector acceleration sensing can be realized.
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Various products made from biodegradable polymers have been increasing rapidly in the market since the use of non-biodegradable materials has been banned, particularly for the disabled packaging materials. Burning remains the most popular method that is increasingly used in treating city wastes. The impact of these polymers on environmental during thermal degradation and combustion is an important issue for city waste management. In this work, the thermal degradation and combustion behaviours of the most popular synthetic biodegradable polymers in the market, poly(lactide acid) (PLA), poly(e-caprolactone) (PCL), poly(butylene succinate) (PBS), poly(butylene adipate-co-terephthalate) (PBAT) and polyhydroxyalkenoates (PHA), are investigated. Both isothermal and non-isothermal thermal decomposition in oxygen and nitrogen environment were studied using thermogravimetric analysis combining with differential scanning calorimeter and coupled with Fourier transform infrared spectroscopy and gas chromatograph/mass spectroscopy. The combustion behaviour was investigated by a combustion colorimeter. The study results show that thermal degradation temperatures are PCL > PBS > PLA > PBAT > PHA. The thermal decomposition of all the polyesters started from scission reaction (cis-elimination), and then a stereoselective cis-elimination, which resulted in the formation of trans-crotonic acid and its oligomers. They all decomposed into CO2 and water in excess oxygen environment above 800°C. Various chemical products with smaller molecules were detected under oxygen-free conditions, including oligomers and unsaturated carboxylic acid. The order of the total heat release of the materials from high to low is as follows: PHA > PCL > PBAT > PBS > PLA. The combustion values of these polyesters are lower than those of polyolefins; thus, they will not damage furnace used currently. The results provide some important and useful data for managing these new city waste.
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Poliésteres , Polímeros , Polímeros/química , Poliésteres/química , Poliésteres/metabolismo , TemperaturaRESUMEN
In this Letter, we propose and experimentally demonstrate fiber Bragg grating (FBG) fabrication in a flexible and stretchable coreless polymer optical fiber. The flexible polymer optical fiber is prepared with polydimethylsiloxane (PDMS). Femtosecond laser direct writing and slit beam shaping are used to form periodic grating structures in the fiber. The fabricated FBG exhibits a large strain measurement range and a blueshift response to temperature. Moreover, it offers low humidity sensitivity due to its low permeability toward water vapor. Taking advantage of the unique sensing performances of the PDMS fiber, the proposed FBG has considerable advantages over the traditional silica FBG devices for strain and temperature sensing.
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In this Letter, a helical-sampled fiber Bragg gratings (HSFBGs) fabrication using a femtosecond laser point-by-point (PBP) technique is proposed. The unique helical structure generates sampled gratings owing to its periodicity. A simple, single-step method for inscription of the sampled gratings is described. The effects of geometrical parameters, including length of grating, helical diameter, helical pitch, and off-axis distance on the resonances are studied, and a series of comb-like spectra are obtained.
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We propose an ultrahigh-order fiber Bragg grating (UHO-FBG) containing dense resonants and its application as a novel filtering device in multi-wavelength lasers. The UHO-FBG is fabricated by femtosecond laser plane-by-plane direct inscription. Thanks to the plane-by-plane inscription, high-order Bragg resonances can be formed with multiple reflectance peaks of comparable reflectance in the range of the fiber operating bandwidth and without the transmission depression of long-period gratings in the transmission spectrum. We also experimentally demonstrate the use of UHO-FBG pairs in a distributed Bragg reflector laser, enabling the excitation of multi-wavelength lasers.
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This study aimed to translate the Spiritual Perspectives Scale (SPS) into a Mandarin Chinese version (C-SPS) and evaluate its psychometric properties among 154 palliative care nurses from twelve community healthcare centres in Shanghai, China. Exploratory factor analysis suggested two factors (spiritually related activities and spiritual beliefs), accounting for 67.49% of the total variance. The Cronbach's α of the total C-SPS score was 0.89, and its split-half coefficient (Spearman-Brown reliability coefficient) was 0.72. The C-SPS showed consistently acceptable psychometric properties of reliability and validity. It can be used to evaluate the level of spiritual perspectives of nurses in China.
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Cuidados Paliativos , Espiritualidad , China , Humanos , Psicometría , Reproducibilidad de los Resultados , Encuestas y CuestionariosRESUMEN
A highly localized eccentric fiber Bragg grating (EFBG) accelerometer was proposed, and its orientation-dependent measurement results were demonstrated experimentally. An EFBG was inscribed point-by-point (PbP) in a single-mode fiber (SMF) using a femtosecond laser, and the cladding mode was recoupled to excite the ghost mode through an abrupt taper. Owing to the asymmetry caused by the lateral offset of the EFBG, the ghost mode showed a significant directional response to acceleration. Furthermore, monitoring the fundamental core mode resonance can help calibrate accidental power perturbation or cross-sensitivity.
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A two-dimensional vector bending sensor that is both compact and simple is proposed and demonstrated, based on an edge-core cladding-type fiber Bragg grating (ECLFBG) inscribed in an edge-core. The ECLFBG is written parallel to the edge-core using a femtosecond laser point-by-point technique. The reflection spectrum of this ECLFBG varies significantly depending on the magnitude and direction of the fiber's bend. Combining the trend and sensitivity of the wavelength shift and reflection intensity variations of the ECLFBG, the bending magnitude and direction can be measured simultaneously.
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We propose and demonstrate a novel, to the best of our knowledge, two-dimensional vector accelerometer based on orthogonal cladding fiber Bragg gratings (FBGs) inscribed in a standard single-mode fiber (SMF). The cladding FBGs are written by a femtosecond laser point-by-point technique and run parallel with the core. We experimentally demonstrate that the two orthogonal components of acceleration can be directly detected using simplified power-referenced detection. Using this structure, we can simultaneously obtain orientation information and acceleration in a SMF.
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This study proposes a novel, to the best of our knowledge, development of fluorotellurite glass fiber Bragg gratings (FBGs). Shell-like morphology was achieved using a single femtosecond laser pulse illuminated through the fiber's polymer coating. Different FBG fabrication methods and parameters were systematically studied to optimize performance. The fluorotellurite FBG exhibited a high sensitivity to writing laser power and reflectivity saturation effect in repetitive writing. A low-insertion-loss fluorotellurite FBG with a reflectivity of over 99% and bandwidth of less than 1 nm was successfully inscribed. The flexible inscription methods can write an FBG at any wavelength in the fluorotellurite glass transparent window, and are applicable to infrared fiber lasers or sensors.
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The exact prevalence of mirror syndrome remains unclear, and the precise clinical features need to be disclosed. We retrospectively reviewed 85 cases of foetal hydrops from a total of 98,484 deliveries. Of these 16 showed mirror syndrome, while 69 did not. The incidence of mirror syndrome among all deliveries was 0.0162%, while that among patients with foetal hydrops was 23.2%. Maternal symptoms of mirror syndrome included anaemia (n = 15), hypertension (n = 7), proteinuria (n = 8), pulmonary oedema (n = 3), cardiac failure (n = 2) and HELLP syndrome (n = 2). Placental thickness, placental weight and amniotic fluid index were significantly different between the groups. In the mirror syndrome group, uric acid, lactate dehydrogenase, creatinine and D-dimer levels were significantly higher (p < .05), whereas haemoglobin, serum albumin levels, haematocrit value and platelet count were significantly lower (p < .05). Elevated uric acid, lactate dehydrogenase and D-dimer levels may be useful as predictors of mirror syndrome.Impact statementWhat is already known on this subject? As mirror syndrome is uncommon and under-diagnosed, its exact incidence is not yet clear, and most publications are case reports or reviews of case reports.What the results of this study add? The incidence of mirror syndrome among all deliveries was 0.0162%, while that among patients with foetal hydrops was 23.2%. Pregnant women who develop mirror syndrome may show severe complications of pregnancy. Attention should be paid to the further progress of the condition. Placental thickness, placental weight and amniotic fluid index were significantly different between those with mirror syndrome and those without. In the mirror syndrome group, the uric acid, lactate dehydrogenase, creatinine and D-dimer levels were significantly higher (p < .05), whereas haemoglobin level, haematocrit value, platelet count and serum albumin level were significantly lower (p < .05).What the implications are of these findings for clinical practice and/or further research? Mirror syndrome is not rare among patients with foetal hydrops. Elevated uric acid, lactate dehydrogenase and D-dimer levels may be useful as predictors of mirror syndrome.
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Edema/patología , Hidropesía Fetal/patología , Complicaciones del Embarazo/patología , Adulto , Edema/sangre , Edema/complicaciones , Femenino , Humanos , Placenta/patología , Embarazo , Complicaciones del Embarazo/sangre , Complicaciones del Embarazo/etiología , Estudios Retrospectivos , SíndromeRESUMEN
We demonstrate a fiber-optic 3D vector displacement sensor based on the monitoring of Bragg reflection from an eccentric grating inscribed in a depressed-cladding fiber using the femtosecond laser side-illumination and phase-mask technique. The compact sensing probe consists of a short section of depressed cladding fiber (DCF) containing eccentrically positioned fiber Bragg gratings. The eccentric grating breaks the cylindrical symmetry of the fiber cross-section and further has bending orientation-dependence. The generated fundamental resonance is strongly sensitive to bending of the fiber, and the direction of the bending plane can be determined from its responses. When integrated with axis strain monitoring, the sensor achieves a 3D vector displacement measurement via simple geometric analysis.
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A high-resolution fiber-optic ultrasonic sensor based on a suspended-core fiber was designed and experimentally demonstrated. The intrinsic Fabry-Perot interferometer consisting of a micro suspended-core from acid corrosion of a grapefruit fiber proved highly sensitive to a wide range of ultrasonic wave (UW) frequencies. A compact interrogation system using spectral sideband filtering was constructed for UW detection. The sensor exhibited significantly improved spatial resolution and detection sensitivity by etching the suspended-core diameter to few microns. Sensor fabrication involves only fiber splicing and corrosion, which provide a self-shielding cladding surrounding and protecting the core from collisions. This sensor is an excellent candidate for high-quality UW detection.
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A fringe visibility enhanced fiber-optic Fabry-Perot interferometer based ultrasonic sensor is proposed and experimentally demonstrated for seismic physical model imaging. The sensor consists of a graded index multimode fiber collimator and a PTFE (polytetrafluoroethylene) diaphragm to form a Fabry-Perot interferometer. Owing to the increase of the sensor's spectral sideband slope and the smaller Young's modulus of the PTFE diaphragm, a high response to both continuous and pulsed ultrasound with a high SNR of 42.92 dB in 300 kHz is achieved when the spectral sideband filter technique is used to interrogate the sensor. The ultrasonic reconstructed images can clearly differentiate the shape of models with a high resolution.
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Cytoplasmic male sterility (CMS) is primarily caused by chimeric genes located in the mitochondrial genomes. In Brassica juncea, orf288 has been identified as a CMS-associated gene in the hau CMS line; however, neither the specific abortive stage nor the molecular function of the gene have been determined. We therefore characterized the hau CMS line, and found that defective mitochondria affect the development of archesporial cells during the L2 stage, leading to male sterility. The expression level of the orf288 transcript was higher in the male-sterility line than in the fertility-restorer line, although no significant differences were apparent at the protein level. The toxicity region of ORF288 was found to be located near the N-terminus and repressed growth of Escherichia coli. However, transgenic expression of different portions of ORF288 indicated that the region that causes male sterility resides between amino acids 73 and 288, the expression of which in E. coli did not result in growth inhibition. Transcriptome analysis revealed a wide range of genes involved in anther development and mitochondrial function that were differentially expressed in the hau CMS line. This study provides new insights into the hau CMS mechanism by which orf288 affects the fertility of Brassica juncea.
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Expresión Génica , Planta de la Mostaza/fisiología , Infertilidad Vegetal/genética , Proteínas de Plantas/genética , Núcleo Celular/genética , Planta de la Mostaza/genética , Planta de la Mostaza/metabolismo , Proteínas de Plantas/metabolismoRESUMEN
We propose and experimentally demonstrate an orientation-dependent fiber-optic bending sensor. The sensing probe consists of a fiber Bragg grating inscribed in both the fiber core and the surrounding cladding of a section of a side-hole fiber. We utilized a side-illumination technique using a femtosecond laser to achieve the grating structure formation. The transmission intensities of both resonances are highly sensitive bending of the fiber, and the bending response shows orientation dependence. The surrounding temperature fluctuation causes a wavelength shift, but not an intensity variation. Therefore, the proposed sensor can be employed for simultaneous measurement of bending and temperature.
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KEY MESSAGE: Different mitotype-specific markers were developed to distinguish different cytoplasms in Brassica napus L. Mitotype-specific markers have been developed to distinguish different mitotypes in plant. And use of molecular markers to identify different mitotypes in Brassica napus would enhance breeding efficiency. Here, we comparatively analyzed six sequenced mitochondrial genomes in Brassica napus and identified collinear block sequences and mitotype-specific sequences (MSSs) of these mitochondrial genomes. The collinear block sequences between mitochondrial genomes of nap, cam, and pol cytoplasmic male sterility (CMS) lines were higher than those of other lines. After comparative analysis of the six sequenced mitochondrial genomes (cam, nap, ole, pol CMS, ogu CMS, and hau CMS), 90 MSSs with sizes ranging from 101 to 9981 bp and a total length of 103,756 bp (accounting for 6.77% of the mitochondrial genome sequences) were identified. Additionally, 12 mitotype-specific markers were developed based on the mitochondrial genome-specific sequences in order to distinguish among these different mitotypes. Cytoplasms of 570 different inbred lines collected across scientific research institutes in China were identified using the MSS markers developed in our study. In addition to confirming the accuracy of the cytoplasmic identification, we also identified mitotypes that have not been reported in Brassica napus. Our study may provide guidance for the classification of different mitotypes in B. napus breeding.