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Objective: This cross-sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID-19 in China. Methods: This study was conducted by 45 tertiary Grade-A hospitals in China. Online and offline questionnaire data were obtained from patients infected with COVID-19 between December 28, 2022, and February 21, 2023. The collected information included basic demographics, medical history, smoking and drinking history, vaccination history, changes in olfactory and gustatory functions before and after infection, and other postinfection symptoms, as well as the duration and improvement status of olfactory and gustatory disorders. Results: Complete questionnaires were obtained from 35,566 subjects. The overall incidence of olfactory and taste dysfunction was 67.75%. Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste dysfunction. Having received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such dysfunction. Before infection, the average olfactory and taste VAS scores were 8.41 and 8.51, respectively; after infection, they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the survey. The median duration of dysosmia and dysgeusia was 15 and 12 days, respectively, with 0.5% of patients having symptoms lasting for more than 28 days. The overall self-reported improvement rate was 59.16%. Recovery was higher in males, never smokers, those who received two or three vaccine doses, and those that had never experienced dental health issues, or chronic accompanying symptoms. Conclusions: The incidence of dysosmia and dysgeusia following infection with the SARS-CoV-2 virus is high in China. Incidence and prognosis are influenced by several factors, including sex, SARS-CoV-2 vaccination, history of head-facial trauma, nasal and oral health status, smoking and drinking history, and the persistence of accompanying symptoms.
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OBJECTIVE: To evaluate the effects of membrane induced by antibiotic-loaded bone cement in skin grafting for tendon exposed wound healing. METHODS: A total of 10 traumatic patients with tendon exposed wound were admitted to our department between February 2016 and December 2018, including 6 males and 4 females, with a mean age of 34.6 years old (ranged, 19 to 43 years old), and treatment duration ranged from 2 to 6 months. There were 7 cases of traffic accidents, 3 cases of mechanical belt injuries, including 8 cases of lower leg and foot wounds and 2 cases of hand back wounds. These tendons exposed wound were covered by antibiotic-loaded bone cement at the earlier stageto induce the formation of the biomembrane, and then skin grafting were performed on the induced membrane. The survival, appearance, texture, sensation of the skin grafting and healing condition of the wounds were studied. RESULTS: Among the 10 patients, skin graft survived well in 8 patients. Partial skin graft necrosis occurred in 2 patients and cured by dressing. CONCLUSION: Using antibiotic bone cement to seal the wound to form induction membrane followed by skin grafting can effectively repair the tendon exposed wound, which has the characteristics of simple operation and less trauma.
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Cicatrización de Heridas , Adulto , Antibacterianos , Cementos para Huesos , Femenino , Humanos , Masculino , Procedimientos de Cirugía Plástica , Trasplante de Piel , Traumatismos de los Tejidos Blandos , Tendones , Resultado del Tratamiento , Adulto JovenRESUMEN
Biodegradable magnesium (Mg)-based alloys have aroused great concern owing to their promising characteristics as temporary implants for orthopedic application. But their undesirably rapid corrosion rate under physiological conditions has limited the actual clinical application. This study reports the use of a novel biomimetic polyelectrolyte multilayer template, based on polyvinylpyrrolidone (PVP) and polyacrylic acid (PAA) via layer-by-layer (LbL) assembly, to improve the corrosion resistance of the alloy. Surface characterization techniques (field-emission scanning electron microscopy, Fourier transform infrared (FTIR) spectrophotometer and X-ray diffractometer) confirmed the formation of biomineralized Ca-P coating on AZ31 alloy. Both hydrogen evolution and electrochemical corrosion tests demonstrated that the corrosion protection of the polyelectrolyte-induced Ca-P coating on AZ31 alloy. The formation mechanism of biomineralized Ca-P coating was proposed.
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The studies of topological phases of matter have been developed from condensed matter physics to photonic systems, resulting in fascinating designs of robust photonic devices. Recently, higher-order topological insulators have been investigated as a novel topological phase of matter beyond the conventional bulk-boundary correspondence. Previous studies of higher-order topological insulators have been mainly focused on the topological multipole systems with negative coupling between lattice sites. Here we experimentally demonstrate that second-order topological insulating phases without negative coupling can be realized in two-dimensional dielectric photonic crystals. We visualize both one-dimensional topological edge states and zero-dimensional topological corner states by using the near-field scanning technique. Our findings open new research frontiers for photonic topological phases and provide a new mechanism for light manipulating in a hierarchical way.
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As a result of their good biocompatibility, bioactivity, and mechanical properties, magnesium (Mg) alloys have received considerable attention as next generation biodegradable implants. Herein, in order to achieve a proper degradation rate and good antibacterial ability, we reported a novel hydroxyapatite coating induced by gentamicin (GS)-loaded polymeric multilayers for the surface treatment of the Mg alloy. The coating was characterized by X-ray diffraction, fourier transform infrared spectroscopy and scanning electron microscopy. The as-prepared hydroxyapatite coating showed the compact morphology and a well-crystallized apatite structure. This coating could improve the adhesion strength and reduce the corrosion rate of the substrate in simulated body fluid solution. Meanwhile, the drug release and antibacterial experiments demonstrated that the GS loaded specimen revealed a significant antimicrobial performance toward Staphylococcus aureus and had a prolonged release profile of GS, which would be helpful to the long-term bactericidal activity of the Mg implant. This coating showed acceptable biocompatibility via MTT assay and Live/dead staining. Thus, the multilayers-hydroxyapatite coated Mg alloy could improve the corrosion resistance and biocompatibility while delivering vital drugs to the site of implantation.
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Aleaciones/química , Antibacterianos/farmacología , Materiales Biocompatibles Revestidos/química , Durapatita/química , Gentamicinas/farmacología , Magnesio/química , Polímeros/química , Resinas Acrílicas/química , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Corrosión , Concentración de Iones de Hidrógeno , Ratones , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos , Propiedades de Superficie , Difracción de Rayos XRESUMEN
Graphene plasmon has attracted extensive interest due to the unprecedented electromagnetic confinement, long propagation distance, and tunable plasmonic frequency. Successful applications of graphene plasmon as infrared sensors have been recently demonstrated, yet they are mainly focused on solid/solid and solid/gas interfaces analysis. Herein, we, for the first time, propose a graphene plasmon-enhanced infrared sensor based on attenuated total reflection configuration for in situ analysis of aqueous-phase molecules. This IR sensor includes a boron-doped graphene (BG) nanodisk array fabricated on top of a ZnSe prism surface that supports attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRA). Our ATR-SEIRA platform is efficient and straightforward for in situ and label-free monitoring of the interaction of biomolecules without interference from the environments, allowing for the extraction of instant spectroscopic information in a complex biological event. Utilizing the near-field enhancement of graphene plasmon, the binding interaction of L-selectin with its aptamer as a demonstration has been investigated to evaluate the specific protein recognition process. The detection limit of the target protein reaches 0.5 nM. Our work demonstrates that chemical-doped graphene plasmon combined with ATR-SEIRA is a promising signal enhancement platform for in situ aqueous-phase biosensing.
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Técnicas Biosensibles , Grafito/química , Espectrofotometría Infrarroja/métodos , Resonancia por Plasmón de Superficie/métodos , Selectina L/química , Nanoestructuras , Unión Proteica , AguaRESUMEN
BACKGROUND: Some problems have been found in the usually adopted combined approach for the removal of intra-extracranial tumors in skull base. Herein, we described a pure endoscopic transnasal or transoral approach (ETA) for the removal of intra-extracranial tumors in various skull base regions. METHODS: Retrospectively, clinical data, major surgical complications, pre- and postoperative images, and follow-up information of a series of 85 patients with intra-extracranial tumors in various skull base regions who were treated by surgery via ETA in our skull base center during the past 10 years were reviewed and analyzed. RESULTS: Gross total tumor removal was achieved in 80/85 cases (94.1%) in this study. All 37 cases with tumors in anterior skull base and all 14 cases with tumors in jugular foramen received total tumor removal. Thirteen and three cases with tumors in clivus received total and subtotal tumor removal, respectively. Total and subtotal tumor removal was performed for 16 cases and 2 cases in lateral skull base, respectively. The complications in this study included: cerebrospinal fluid leakage (n = 3), meningitis (n = 3), and new cranial nerve deficits (n = 3; recovered in 3 months after surgery). In the follow-up period of 40-151 months (median: 77 months), seven patients (8.8%) out of the 80 cases of total tumor removal experienced recurrence. CONCLUSIONS: Complete resection of intra-extracranial growing tumors in various skull base regions can be achieved via the pure ETA in one stage in selected cases. Surgical procedure for radical removal of tumors is feasible and safe.
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Procedimientos Neuroquirúrgicos/métodos , Neoplasias de la Base del Cráneo/cirugía , Base del Cráneo/patología , Base del Cráneo/cirugía , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Neoplasias Meníngeas/patología , Neoplasias Meníngeas/cirugía , Meningioma/patología , Meningioma/cirugía , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Estudios Retrospectivos , Neoplasias de la Base del Cráneo/patología , Adulto JovenRESUMEN
OBJECTIVE: To investigate the expression of p16, cyclin D1, retinoblastoma tumor suppressor protein (Rb) and MIB-1 in skull base chordoma and chondrosarcoma tissues, and to determine the clinicopathological significance of the above indexes in these diseases. METHODS: A total of 100 skull base chordoma, 30 chondrosarcoma, and 20 normal cartilage tissue samples were analyzed by immunohistochemistry. The expression levels of p16, cyclinD1, Rb and MIB-1 proteins were assessed for potential correlation with the clinicopathological features. RESULTS: As compared to normal cartilage specimen (control), there was decreased expression of p16, and increased expression of cyclin D1, Rb and MIB-1 proteins, in both skull base chordoma and chondrosarcoma specimens. MIB-1 LI levels were significantly increased in skull base chordoma specimens with negative expression of p16, and positive expression of cyclin D1 and Rb (P < 0.05). Significantly elevated MIB-1 LI was also detected in skull base chondrosarcoma tissues, while there was negative expression of p16, cyclin D1 and Rb (P < 0.05). In skull base chordoma, p16 negatively correlated with cyclin D1 and Rb, while cyclin D1 positively correlated with Rb. Additionally, p16, cyclin D1, Rb, or MIB-1 expression showed no correlation with age, gender, or pathological classification of patients with skull base chordoma (P > 0.05). However, p16 and MIB-1 levels correlated with the intradural invasion, and expression of p16, Rb and MIB-1 correlated with the number of tumor foci (P < 0.05). Further, the expression of p16 and MIB-1 appeared to correlate with the prognosis of patients with skull base chordoma. CONCLUSIONS: The abnormal expression of p16, cyclin D1 and Rb proteins might be associated with the tumorigenesis of skull base chordoma and chondrosarcoma.
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BACKGROUND: Isoflavones are naturally occurring plant chemicals belonging to the "phytoestrogen" class. The aim of the present study was to examine the effects of isoflavones obtained from Cordyceps sinensis (CSIF) on development of estrogen deficiency-induced osteoporosis in ovariectomized rats. METHODS: After the rats were treated orally with CSIF, serum alkaline phosphatase (ALP), tartarate resistant acid phosphatase (TRAP), serum osteocalcin (OC), homocysteine (HCY), C-terminal crosslinked telopeptides of collagen type I (CTX), estradiol and interferonγ (IFN-γ) level were examined. At the same time, the urine calcium, plasma calcium, plasma phosphorus and the mass of uterus, thymus and body were also examined. RESULTS: The beneficial effects of CSIF on improvement of osteoporosis in rats were attributable mainly to decrease ALP activity, TRAP activity, CTX level and IFN-γ level. At the same time, CSIF also increase the OC and estradiol level in ovariectomized osteopenic rats. The histological examination clearly showed that dietary CSIF can prevent bone loss caused by estrogen deficiency. CONCLUSION: The significant estrogenic activity of CSIF demonstrated that CSIF has significant estrogenic effects in OVX rats.
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Productos Biológicos/uso terapéutico , Conservadores de la Densidad Ósea/uso terapéutico , Cordyceps/química , Isoflavonas/uso terapéutico , Osteoporosis/tratamiento farmacológico , Fitoestrógenos/uso terapéutico , Fitoterapia , Fosfatasa Ácida/sangre , Fosfatasa Alcalina/sangre , Animales , Productos Biológicos/farmacología , Conservadores de la Densidad Ósea/farmacología , Enfermedades Óseas Metabólicas/sangre , Enfermedades Óseas Metabólicas/tratamiento farmacológico , Colágeno Tipo I/metabolismo , Estradiol/sangre , Estrógenos/deficiencia , Femenino , Humanos , Interferón gamma/sangre , Isoflavonas/farmacología , Osteocalcina/sangre , Osteoporosis/sangre , Osteoporosis/etiología , Osteoporosis/patología , Ovariectomía , Fósforo/sangre , Fitoestrógenos/farmacología , Ratas , Ratas Wistar , Útero/efectos de los fármacosRESUMEN
Distance-dependent signal intensity in immunoassay by attenuated total reflection-surface enhanced infrared absorption spectroscopy is demonstrated by controlling the distance of target proteins away from the enhancement substrate. Based on this optical near-field effect, sensitive detection of protein molecules with a detection limit of 0.6 nM and investigation of the kinetics and thermodynamics of protein-aptamer/antibody interactions can be achieved.
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Anticuerpos/inmunología , Antígenos/inmunología , Aptámeros de Péptidos/inmunología , Inmunoensayo/métodos , Proteínas/análisis , Espectrofotometría Infrarroja/métodos , Selectina L/análisis , TermodinámicaRESUMEN
The effect of cordycepin (3'-deoxyadenosine) on inflammation-induced osteoporosis (IMO) was studied in this paper. After the rats were treated orally with cordycepin (20 mg/kg), serum osteocalcin (OC), homocysteine (HCY), C-terminal cross-linked telopeptides of collagen type I (CTX), maleic dialdehyde (MDA), polymorphonuclear cells (PMN), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α), they were examined by ELISA or immunohistochemistry. The specimens from the liver were also processed for light microscopic examination. The IMO rats showed a significant increase in plasma CTX, MDA, PMN, IL-1ß, TNF-α, and nitrate levels as well as a significant decrease in plasma OC. These changes were attenuated by cordycepin (20 mg/kg) supplementation in the IMO rats. Examination of the liver specimens revealed mononuclear cell infiltration in the portal areas in the IMO rats which was not detected in the cordycepin (20 mg/kg) rats. These results suggest that cordycepin may act as an anti-inflammatory agent in magnesium silicate-induced inflammation in osteoporosis.
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Colágeno Tipo I/metabolismo , Citocinas/metabolismo , Desoxiadenosinas/farmacología , Inflamación/metabolismo , Neutrófilos/citología , Osteoporosis/metabolismo , Aldehídos/metabolismo , Animales , Regulación hacia Abajo , Interleucina-1beta/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Óxido Nítrico/metabolismo , Osteoporosis/tratamiento farmacológico , Ratas , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Surface modification of biomedical magnesium alloy using composite coating shows an attemptable approach for the development of Mg-based biomaterials with excellent cytocompatibility. Hydroxyapatite/collagen composite was preliminarily fabricated by biomineralization, the bioactive poly(l-lactic acid)/hydroxyapatite/collagen composite coatings were spin coated on AZ31 magnesium alloy using poly(l-lactic acid) solution mixed with hydroxyapatite/collagen particles, and the resultant materials and coatings were characterized in structure and related properties; furthermore, the in vitro degradation behavior of modified magnesium alloy in 1.5-fold Hank's solution was investigated. The results show that hydroxyapatite/collagen composite achieved chemical bonding between hydroxyapatite and collagen similar to natural bone; composite coatings on AZ31 magnesium alloy retained the bioactive functional groups of the componential materials and improved the corrosion resistance of Mg alloy; the mass fraction of hydroxyapatite/collagen particles incorporated into the composite affected the porous structure, interfacial adhesion and thus the corrosion resistance of the composite coating due to phase separation as well as volume concentration effects of polymer solution. Composite coatings suppressed the sharp rising of pH value and the released Mg(2+) from substrate to extensive degree, and the degradation behavior of the modified magnesium alloy was supposed to be correlated to microstructure of the coating as well as the synergistic reactions among alkaline- and acidic-degraded products.
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Aleaciones/química , Líquidos Corporales/química , Materiales Biocompatibles Revestidos/síntesis química , Colágeno Tipo I/química , Durapatita/química , Ácido Láctico/química , Polímeros/química , Análisis de Falla de Equipo , Ensayo de Materiales , Poliésteres , Porosidad , Prótesis e Implantes , Diseño de Prótesis , Propiedades de SuperficieRESUMEN
Taking two winter wheat cultivars Ji' nan 17 and Shannong 8355 as test materials, this paper measured the superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities and the malondialdehyde (MDA) and soluble protein contents in the functional leaves and sheaths of the tillers at different positions at stem elongation stage under low temperature stress, and then, the freezing resistance of the tillers was comprehensively evaluated by the methods of principal component analysis and cluster analysis. The results showed that under low temperature stress, the SOD, POD, and CAT activities in the functional leaves and sheaths of each tiller at stem elongation stage increased, but the MDA and soluble protein contents increased or decreased to some extent. By using principal component analysis and cluster analysis, the tillers of each cultivar were grouped into three kinds of freezing resistance type. For Ji' nan 17, the main stem, tiller I, and tiller II belonged to high freezing resistance type, the tiller III, tiller IV, and tiller I p belonged to medium freezing resistance type, and the tiller II p belonged to low freezing resistance type. For Shannong 8355, the main stem, tiller I, tiller II, and tiller III belonged to high freezing resistance type, the tiller IV and tiller I p belonged to medium freezing resistance type, and the tiller II p belonged to low freezing resistance type. It was concluded that the freezing resistance of the winter wheat tillers at different positions at stem elongation stage differed, with the lower position tillers being more resistant than the higher position tillers.
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Adaptación Fisiológica/fisiología , Agricultura/métodos , Frío , Triticum/fisiología , China , Ecosistema , Hojas de la Planta/metabolismo , Tallos de la Planta/metabolismo , Tallos de la Planta/fisiología , Estaciones del Año , Estrés Fisiológico/fisiología , Superóxido Dismutasa/metabolismo , Triticum/metabolismoRESUMEN
OBJECTIVE: The early experience of treating anterior skull base meningiomas with intra-extracranial extension via pure endoscopic endonasal approach (EEA) was presented, the safety, feasibility and preliminary treatment outcomes were investigated. METHODS: Eight patients with intra-extradural meningiomas who were admitted from October 2006 to October 2010 were operated on via EEA in one stage in Xuanwu hospital. In this study, the operative technique was described, the degree of resection, complications and the early clinical outcomes were discussed. RESULTS: The complete resection of meningiomas with intra-extracranial extension was achieved in all patients using EEA in one stage. Preoperative visual symptoms were improved or resolved in all cases who presented with preoperative visual complaints. No patient in our series experienced a new neurological deficit after surgery or recurrence and death related meningiomas in the follow-up period (33-75 months). One patient experienced postoperative cerebrospinal fluid leak, delayed meningitis and secondary hydrocephalus which responded to therapy. After treatment, the patient was cure. CONCLUSION: Our limited experience indicates that EEA is feasible and safe for the complete resection of anterior skull base meningiomas with intra- and extracranial extension in one stage in selected cases.
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Neoplasias Meníngeas/cirugía , Meningioma/cirugía , Neoplasias de la Base del Cráneo/cirugía , Adulto , Anciano , Endoscopía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nariz/cirugía , Base del Cráneo/cirugía , Resultado del TratamientoRESUMEN
OBJECTIVE: To report a new approach, endoscopic transoral approach for the resection of jugular foramen schwannoma. METHODS: Nine patients with jugular foramen schwannoma (three males and six females, ranging in age from 15 to 61 years old) were treated by direct surgery via a pure endoscopic transoral approach to the jugular foramen. Eight patients complained of hypoglossal nerve palsy with hemiatrophy of the tongue; six cases complained of vagus nerve palsy. Three cases complained of glossopharyngeal nerve palsy, one case complained of facial nerve palsy and hearing loss. RESULTS: The nerves in this area were preserved and radical intracapsular removal of the tumor was performed via endoscopic transoral approach in the nine cases. Tumor removal, as assessed by intraoperative endoscopic inspection, postoperative magnetic resonance imaging and clinical evaluation, revealed all tumors were completely removed. One patient suffered from temporary swallowing difficulties and temporary right vagus palsy 1 day after surgery. There were no others intraoperative and postoperative complications. All patients were followed up for 4 - 29 months, no recurrences were occurred in all these patients and the muscle bulk, motor and the pre-postoperative swallowing function, the vagus palsy, the facial nerve palsy and hearing loss had improved in these patients. CONCLUSION: The endoscopic transoral approach and intracapsular removal of the tumor provided for successful minimally invasive surgery in the jugular foramen schwannomas.
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Neurilemoma/cirugía , Procedimientos Quirúrgicos Otorrinolaringológicos/métodos , Neoplasias de la Base del Cráneo/cirugía , Adolescente , Adulto , Endoscopía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Taking two winter wheat varieties Gaocheng 8901 and Yannong 21 with different end-use qualities as test objects, a field experiment was conducted in the experimental farm of Shandong Agricultural University from 2008 to 2010, aimed to study the effects of different planting density and spraying PP333 on the basal stem morphological characteristics, snapping-resistance, lodging-resistant index, and grain yield. Gaocheng 8901 had higher lodging-resistance but lower grain yield than Yannong 21. Comparing with low planting density (180 x 10(4) basic seedlings per hm2), high planting density (240 x 10(4) basic seedlings per hm2) decreased the culm snapping-resistance and lodging-resistant index of the two varieties, especially Yannong 21. Spraying PP333 decreased the plant height and the basal internodes length, increased the snapping-resistance and lodging-resistant index, strengthened the lodging-resistance, and improved the spike number and grain yield. Correlation analysis showed that the second internode length, percentage of basal internodes (1 + 2) length to total internode length, and apparent lodging ratio were significantly negatively correlated with culm lodging resistant index. Therefore, to adopt an appropriate planting density combined with spraying PP333 could improve the lodging-resistance of winter wheat and its grain yield, being an important high-yielding cultivation technique for wheat production in sub-humid zone.
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Agricultura/métodos , Biomasa , Reguladores del Crecimiento de las Plantas/farmacología , Tallos de la Planta , Triticum/crecimiento & desarrollo , Ecosistema , Triticum/fisiologíaRESUMEN
A pot experiment with twenty wheat cultivars was conducted to investigate the superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities and the MDA, soluble protein and soluble sugar contents of functional leaves as well as the grain yield, 1000-grain weight, and grain morphological characters under low temperature stress. Low temperature (-4 degrees C) stress at stem elongation stage resulted in the changes of grain morphology and yield characters. For most of test cultivars, their grain length-width ratio, grain roundness, and sterile spikelets increased, and their grain equivalent diameter, grain area, 1000-grain weight, and grain yield decreased. Path analysis indicated that after treated with low temperature at stem elongation stage, the SOD activity and soluble sugar content of functional leaves, especially the SOD activity (direct path coefficient -0. 578) , were the dominant factors affecting grain yield. Taking the percentage of decreased grain yield due to low temperature stress as the assessment criterion, the test twenty winter wheat cultivars were divided into three groups. Cultivars Jimai 19, Jimai 20, Liangxing 99, Shannong 1135, Shannong 8355, Taishan 23, Taishan 9818, Wennong 6, and Yannong 21 belonged to high freeze resistance group, cultivars Linmai 2, Weimai 8, Yannong 19, and Zimai 12 were of low freeze resistance group, and the other seven cultivars belonged to medium freeze resistance group. The seedling stage comprehensive assessment index (D value) had a significant negative correlation with the percentage of decreased grain yield (r = -0. 512*), suggesting that the stronger freeze resistance of wheat at seedling stage was beneficial to the higher wheat grain yield, and seedling stage was the critical period to be selected to identify the freeze resistance of wheat.
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Biomasa , Frío , Estrés Fisiológico/fisiología , Triticum/crecimiento & desarrollo , Triticum/fisiología , Grano Comestible/crecimiento & desarrollo , Peroxidasa/metabolismo , Plantones/clasificación , Plantones/crecimiento & desarrollo , Superóxido Dismutasa/metabolismo , Triticum/clasificaciónRESUMEN
Composite metal-dielectric-metal (MDM) surface plasmon polariton (SPP) structures are first proposed to realize the ultra-short optical splitters with simplified designs. The operation mechanism is based on the contra-directional coupling achieved in composite plasmonic slot waveguides. In certain cases, the switching function can also be realized. It is further shown that based on the same physical mechanism multi-dielectric-core composite MDM structures could serve as a novel plasmonic waveguide crossover component with low cross talk and high throughput.
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Refractometría/instrumentación , Resonancia por Plasmón de Superficie/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , MiniaturizaciónRESUMEN
We have studied filamentation and supercontinuum generation by focusing the intense femtosecond laser pulses into an absorptive medium (CuSO(4) aqueous solution). A broad spectrum from 350 to 950 nm with a flat plateau spanning approximately from 450 to 700 nm with a flatness of 9% is obtained without any additional filters. The results indicate that the absorptive medium not only suppresses the strong surplus femtosecond laser signal but also flattens the supercontinuum spectrum efficiently.
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Self-assembly of colloidal spheres confined within cells of different shapes formed with two slides under capillary forces are studied. It is found that by controlling the shape of the cell the curvature of the drying front can result in a significant effect on the self-organization process. A curved drying front formed within parallel slides is always associated with growth of colloidal crystal structures with a high density of disorder. We demonstrate that single-domain two-dimensional colloidal crystals with centimeter size can be grown under capillary forces under a straight drying front formed in a wedge-shaped cell. These findings are demonstrated by laser diffraction, microscopy imaging methods and off-normal optical transmission measurements. The present growth method should be of importance in expanding colloidal crystal applications in angle-resolved nanosphere lithography, as well as in preparation of high-quality quasi-three-dimensional plasmonic crystals.