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BACKGROUND: The prevalence of skin redundancy and lack of creases in the Asian upper eyelids makes blepharoplasty popular. Although many incision designs have been developed to improve upper eyelid laxity, there is a lack of a universal method to match various upper eyelid conditions. We present a systematic preoperative evaluation and design approach that incorporates eye esthetics to determine the shape and amount of skin to be removed to create attractive eyes. METHODS: A retrospective review of 352 patients who underwent incisional blepharoplasty from May 2020 to May 2022 was performed. The excised area was determined preoperatively according to the degree of upper eyelid skin laxity, and the best of the three precise designs is chosen. RESULTS: All patients undergoing the procedure achieved a satisfactory eyelid appearance immediately after surgery. Patients were followed up for 3 to 12 months. All patients had significant improvement in upper eyelid skin laxity and a natural shape of the eyelid. No defects that required revision surgery to improve were present, and 91.7% of the patients were satisfied with the long-term outcome. CONCLUSIONS: This systematic approach to preoperative design is simple, effective, and feasible to avoid scar exposure while addressing the lateral hood and achieve an attractive blepharoplasty appearance.
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The cellular functions, such as tissue-rebuilding ability, can be directly affected by the metabolism of cells. Moreover, the glucose metabolism is one of the most important processes of the metabolism. However, glucose cannot be efficiently converted into energy in cells under ischemia hypoxia conditions. In this study, a high-energy intermediate fructose hydrogel (HIFH) is developed by the dynamic coordination between sulfhydryl-functionalized bovine serum albumin (BSA-SH), the high-energy intermediate in glucose metabolism (fructose-1,6-bisphosphate, FBP), and copper ion (Cu2+ ). This hydrogel system is injectable, self-healing, and biocompatible, which can intracellularly convert energy with high efficacy by regulating the glucose metabolism in situ. Additionally, the HIFH can greatly boost cell antioxidant capacity and increase adenosine triphosphate (ATP) in the ischemia anoxic milieu by roughly 1.3 times, improving cell survival, proliferation and physiological functions in vitro. Furthermore, the ischemic skin tissue model is established in rats. The HIFH can speed up the healing of damaged tissue by promoting angiogenesis, lowering reactive oxygen species (ROS), and eventually expanding the healing area of the damaged tissue by roughly 1.4 times in vivo. Therefore, the HIFH can provide an impressive perspective on efficient in situ cell energy supply of damaged tissue.
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Higher tree species richness generally increases the storage of soil organic carbon (SOC). However, less attention is paid to the influence of varied tree species composition on SOC storage. Recently, the perspectives for the stronger persistence of SOC caused by the higher molecular diversity of organic compounds were proposed. Therefore, the influences of tree species richness and composition on the molecular diversity of SOC need to be explored. In this study, an index of the evenness of diverse SOC chemical components was proposed to represent the potential resistance of SOC to decomposition under disturbances. Six natural forest types were selected encompassing a diversity gradient, ranging from cold temperate to tropical forests. We examined the correlations of tree species richness, composition, and functional diversity, with the evenness of SOC chemical components at a molecular level by 13 C nuclear magnetic resonance. Across the range, tree species richness correlated to the evenness of SOC chemical components through tree species composition. The negative correlation of evenness of SOC chemical components with tree species composition, and the positive correlation of evenness of SOC chemical components with tree functional diversity were found. These indicate the larger difference in tree species composition and the lower community functional diversity resulted in the higher heterogeneity of SOC chemical components among the communities. The positive correlation of the evenness of SOC chemical components with the important value of indicator tree species, further revealed the specific tree species contributing to the higher evenness of SOC chemical components in each forest type. Soil fungal and bacterial α-diversity had effect on the evenness of SOC chemical components. These findings suggest that the indicator tree species conservation might be preferrable to simply increasing tree species richness, for enhancing the potential resistance of SOC to decomposition.
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Ecossistema , Árvores , Carbono/análise , Solo/química , Biodiversidade , Florestas , ChinaRESUMO
Stem mammaliaforms are Mesozoic forerunners to mammals, and they offer critical evidence for the anatomical evolution and ecological diversification during the earliest mammalian history. Two new eleutherodonts from the Late Jurassic period have skin membranes and skeletal features that are adapted for gliding. Characteristics of their digits provide evidence of roosting behaviour, as in dermopterans and bats, and their feet have a calcaneal calcar to support the uropagatium as in bats. The new volant taxa are phylogenetically nested with arboreal eleutherodonts. Together, they show an evolutionary experimentation similar to the iterative evolutions of gliders within arboreal groups of marsupial and placental mammals. However, gliding eleutherodonts possess rigid interclavicle-clavicle structures, convergent to the avian furculum, and they retain shoulder girdle plesiomorphies of mammaliaforms and monotremes. Forelimb mobility required by gliding occurs at the acromion-clavicle and glenohumeral joints, is different from and convergent to the shoulder mobility at the pivotal clavicle-sternal joint in marsupial and placental gliders.
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Fósseis , Locomoção , Mamíferos/anatomia & histologia , Mamíferos/fisiologia , Filogenia , Animais , Aves/anatomia & histologia , China , Quirópteros/anatomia & histologia , Quirópteros/fisiologia , Dieta , Membro Anterior/anatomia & histologia , Membro Anterior/fisiologia , Mamíferos/classificação , Marsupiais/fisiologia , Dente Molar/anatomia & histologia , Dente Molar/fisiologia , Ombro/anatomia & histologia , Pele/anatomia & histologia , Crânio/anatomia & histologiaRESUMO
Stem mammaliaforms are forerunners to modern mammals, and they achieved considerable ecomorphological diversity in their own right. Recent discoveries suggest that eleutherodontids, a subclade of Haramiyida, were more species-rich during the Jurassic period in Asia than previously recognized. Here we report a new Jurassic eleutherodontid mammaliaform with an unusual mosaic of highly specialized characteristics, and the results of phylogenetic analyses that support the hypothesis that haramiyidans are stem mammaliaforms. The new fossil shows fossilized skin membranes that are interpreted to be for gliding and a mandibular middle ear with a unique character combination previously unknown in mammaliaforms. Incisor replacement is prolonged until well after molars are fully erupted, a timing pattern unique to most other mammaliaforms. In situ molar occlusion and a functional analysis reveal a new mode of dental occlusion: dual mortar-pestle occlusion of opposing upper and lower molars, probably for dual crushing and grinding. This suggests that eleutherodontids are herbivorous, and probably specialized for granivory or feeding on soft plant tissues. The inferred dietary adaptation of eleutherodontid gliders represents a remarkable evolutionary convergence with herbivorous gliders in Theria. These Jurassic fossils represent volant, herbivorous stem mammaliaforms associated with pre-angiosperm plants that appear long before the later, iterative associations between angiosperm plants and volant herbivores in various therian clades.
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Aclimatação , Evolução Biológica , Orelha Média/anatomia & histologia , Ingestão de Alimentos , Ecossistema , Fósseis , Mamíferos/anatomia & histologia , Mamíferos/fisiologia , Animais , Dieta , Herbivoria , Incisivo , Locomoção , Mamíferos/classificação , Dente Molar , FilogeniaRESUMO
BACKGROUND: The nasal tip plays a crucial role both esthetically and functionally. The application of nasal tip grafts is an effective method for improving nasal tip form. Ear cartilage is a common choice for nasal tip grafts, but it still presents several challenges in clinical application that need to be addressed. This study aims to address the issues associated with the use of ear cartilage in clinical rhinoplasty applications through the development of a novel septal extension graft using ear cartilage for nasal tip reconstruction. METHODS: From May 2018 to April 2022, a total of 132 cases of nasal tip reconstruction surgeries were performed using a seagull-shaped nasal septum extension graft, constructed with bilateral cavum concha cartilage. Among these cases, 25 patients had previously undergone rhinoplasty using silicone implant, 7 patients had undergone augmentation rhinoplasty using expanded polytetrafluoroethylene, whereas the rest were primary rhinoplasty cases. All patients were followed up for a period ranging from 3 months to 4 years postoperatively, with photographs taken to assess the nasal tip morphology. RESULTS: In this study, all patients exhibited good healing of the incisions made at the posterior aspect of the auricular concha, with no occurrences of hematoma and inconspicuous scarring. In 116 cases, significant improvement in nasal appearance and a realistic nasal tip form were achieved postoperatively, yielding satisfactory outcomes. Only 16 patients experienced minor issues with nasal tip morphology, which were subsequently improved through further surgical procedures. CONCLUSION: This study reports a surgical technique for nasal tip refinement using bilaterally harvested cavum concha cartilage to construct a seagull-shaped nasal septal extension graft. The procedure has achieved satisfactory outcomes, and its application is worth extending to clinical practice.
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PURPOSE: In the present study, we aimed to investigate the positive rate of Demodex infection in patients with meibomian gland dysfunction (MGD) and to analyze its risk factors. METHODS: A total of 178 MGD patients admitted to the Jinan Second People's Hospital from April 2020 to February 2021 were enrolled in the present study. All patients were examined for Demodex infection, and their medical history was collected. The positive rate of Demodex infection was calculated after the examination. The medical history, including age, eating habits, pet ownership, and so on, was collected. First, a univariate analysis was conducted to identify the factors associated with positive Demodex infection, and then, a multivariate comprehensive analysis was carried out to identify the main risk factors for positive Demodex infection. RESULTS: In the present study, the positive rate of Demodex infection in 178 MGD patients was 73.60%. The risk factors of Demodex infection in MGD patients were gender, pet ownership, toiletry sharing, and diabetes (all P ≤ 0.15). Age was one of the risk factors for infection [B = 0.105, OR 1.111 (95%CI 1.069-1.155), P = 0.000], and toiletry sharing was more likely to cause positive Demodex mite infection [B = 0.891, OR 2.439 (95%CI 1.066-5.577), P = 0.035]. The Demodex infection was not statistically associated with gender (P = 0.234), pet ownership (P = 1.141), and diabetes (P = 0.295). CONCLUSIONS: The positive rate of Demodex infection was higher in MGD patients. The main risk factors affecting the positive rate of Demodex infection included age and toiletry sharing.
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Doenças Palpebrais , Disfunção da Glândula Tarsal , Infestações por Ácaros , Humanos , Disfunção da Glândula Tarsal/diagnóstico , Infestações por Ácaros/complicações , Infestações por Ácaros/epidemiologia , Glândulas Tarsais , Fatores de Risco , Hospitalização , Lágrimas , Doenças Palpebrais/epidemiologia , Doenças Palpebrais/diagnósticoRESUMO
Nasopharyngeal carcinoma (NPC) is prevalent in East Asia and causes increased health burden. Elucidating the regulatory mechanism of NPC progression is important for understanding the pathogenesis of NPC and developing novel therapeutic strategies. Nasopharyngeal carcinoma and normal tissues were collected. Nasopharyngeal carcinoma cell proliferation, migration, and invasion were evaluated using CCK-8, colony formation, wound healing, and transwell assays, respectively. A xenograft mouse model of NPC was established to analyze NPC cell growth and metastasis in vivo. The expression of miR-106a-5p, FBXW7, TRIM24, and SRGN was determined with RT-qPCR and Western blot. MiR-106a-5p, TRIM24, and SRGN were upregulated, and FBXW7 was downregulated in NPC tissues and cells. Exosomal miR-106a-5p could enter NPC cells, and its overexpression promoted the proliferation, migration, invasion, and metastasis of NPC cells, which were suppressed by knockdown of exosomal miR-106a-5p. MiR-106a-5p targeted FBXW7 to regulate FBXW7-mediated degradation of TRIM24. Furthermore, TRIM24 regulated SRGN expression by binding to its promoter in NPC cells. Suppression of exosomal miR-106a-5p attenuated NPC growth and metastasis through the FBXW7-TRIM24-SRGN axis in vivo. Exosomal miR-106a-5p accelerated the progression of NPC through the FBXW7-TRIM24-SRGN axis. Our study elucidates novel regulatory mechanisms of NPC progression and provides potential exosome-based therapeutic strategies for NPC.
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MicroRNAs , Neoplasias Nasofaríngeas , Animais , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Proteína 7 com Repetições F-Box-WD/genética , Proteína 7 com Repetições F-Box-WD/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologiaRESUMO
Exudate management is critical to improve chronic wound healing. Herein, inspired by a Janus-structured lotus leaf with asymmetric wettability, a Janus electrospun short fiber scaffold is fabricated via electrospinning technologies and short fiber modeling. This scaffold is composed of hydrophilic 2D curcumin-loaded electrospun fiber and hydrophobic 3D short fiber via layer-by-layer assembly and electrostatic interactions which can aggregate the wound exudate by pumping from the hydrophobic layer to the hydrophilic via multiple contact points between hydrophilic and hydrophobic fibers, and simultaneously trigger the cascade release of curcumin in the upper 2D electrospun fiber. The 3D short fiber with high porosity and hydrophobicity can quickly aggregate exudate within 30 s after compounding with hydrophilic 2D electrospun fiber via a spontaneous pump. In vitro experiments show that Janus electrospun short fiber has good biocompatibility, and the cascade release of curcumin can significantly promote the proliferation and migration of fibroblasts. In vivo experiments show that it can trigger cascade release of curcumin by aggregating wound exudate, so as to accelerate wound healing process and promote collagen deposition and vascularization. Hence, this unique biometric Janus scaffold provides an alternative for chronic wound healing.
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Curcumina , Nanofibras , Colágeno , Curcumina/farmacologia , Fibroblastos , Nanofibras/química , Porosidade , CicatrizaçãoRESUMO
A novel high-fabrication-tolerance mode demultiplexer (MD) based on an S-bend waveguide is designed, which is used to split TE1 mode and TE0 mode, and convert the TE1 mode to TE0 mode. Based on the MD, a polarization-rotator-splitter (PRS) is demonstrated. The transmission losses of the fabricated PRS are lower than 0.5 dB and 0.6 dB for TE0 mode and TM0 mode, respectively, in the wavelength span of 1520-1630 nm. And the corresponding polarization extinction ratios are larger than 19.5 dB and 17.6 dB, respectively. This MD has the most compact size comparing with other experimentally demonstrated MDs used in PRS.
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ABSTRACT: Fat repositioning is an effective way to treat tear trough deformity (TTD) in Asians. Recent techniques mainly focused on the fixation technique, whereas how to precisely shape and individually quantify the fat pedicle has been ignored. This article introduced an individualized, targeted, and tension-free technique to fabricate a fan-shaped thin septum fat pedicle for repositioning. Furthermore, a layer-level fixation method was advocated to provide sufficient, continuous, uninterrupted filling of the TTD. From January 1, 2009, to December 31, 2018, 492 patients underwent this procedure. Through a transconjunctival incision, a continuous fan-shaped, tension-free, customized septum fat pedicle was precisely designed to match the TTD anatomy. The pedicle could either be elongated, or thickened, or debulked, or translocated, to meet the patients' individual needs. At the same time, a layer-level fat pedicle fixation technique was applied to fully interrupt the TTD. The mean operation time was 60â±â9.3âminutes. All patients demonstrated a significant improvement with elimination of both eye bags and TTD. High satisfaction was noted among the patients. No obvious resorption of the fat pedicles was observed, and the lower lid contour improvements were durable. One infection occurred after 3âdays of surgery, and was resolved by removal of the suture followed by topical application of iodine and oral antibiotics for 3 to 5âdays. No other complications were observed. Precisely repositioning transconjunctival fat using a layer-level fixation technique with a fan-shaped thin fat pedicle under a subperiosteal plane is an effective, lasting, and safe approach for individually treating TTD.
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Blefaroplastia , Tecido Adiposo/transplante , Pálpebras/cirurgia , Humanos , SuturasRESUMO
Biodiversity is the foundation of all ecosystems across the planet, and having a better understanding of its global distribution mechanism could be important for biodiversity conservation under global change. A niche width model, combined with metabolic theory, has successfully predicted the increase of α-diversity and decrease of ß-diversity in the below-ground microbial community along an altitudinal mountain gradient. In this study, we evaluated this niche width model of above-ground plants (mainly trees and shrubs) and below-ground bulk soil microbial communities (i.e., bacteria and archaea) along a latitudinal gradient of forests in China. The niche widths of both plants and microbes increased with increasing temperature and precipitation, and with proximity to circumneutral pH. However, the α- and ß-diversities (observed richness and Bray-Curtis dissimilarity, respectively) could not be accurately predicted by a single niche width model alone, either temperature, precipitation or pH. Considering the interactions among different niche width models, all three niche width models were combined to predict biodiversity at the community level using structural equation modelling. The results showed that the niche width model of circumneutral pH was most important in predicting diversity profiling (i.e., α- and ß-diversity) for both plants and microbes, while niche width of precipitation and temperature showed both direct and indirect importance for microbe and plant biodiversity, respectively. Because the current niche width model neglects several scenarios related to taxon and environmental attributes, it still needs to be treated with caution in predicting biodiversity trends.
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Biodiversidade , Ecossistema , Microbiologia do Solo , China , Florestas , Plantas , SoloRESUMO
Craniomaxillofacial and plastic surgeons are often confronted with patients who present with enophthalmos caused mainly by trauma. In many patients, one-stage reconstruction repairs only the bony orbit, leaving intact the disfiguring enophthalmos. Thus, some filler is needed to restore the normal volume of the orbit. The authors describe a technique to correct such deformation safely and effectively. Data were collected from 30 enophthalmic patients (average age 36.67â±â11.66 years) who underwent retro-ocular injections of fat globules between August 2014 and July 2018. CT helped identify a safe injection site, and specific CT measurements quantified the volume of fat globules required. There was a significant difference between the preoperative and postoperative values for lateral orbital protrusion (Pâ<â.01), superior orbital protrusion (Pâ<â.01), and orbital volume (Pâ<â.01). Most patients were satisfied with the outcome. There were no significant complications. Injecting fat globules into the retro-orbital area is an effective technique for correcting enophthalmos deformity.
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Enoftalmia/cirurgia , Adolescente , Adulto , Gorduras/administração & dosagem , Feminino , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Órbita/cirurgia , Adulto JovemRESUMO
OBJECTIVE: Complex secondary deformities of cleft lip include nasal and labial deformities, alveolar cleft, oronasal fistula, and so on. In this report, the authors present a method to simultaneously repair the above complex deformities with autogenous costal cartilage and rib grafts. METHODS: The surgical procedure of simultaneous correction includes RESULTS:: Satisfactory outcomes were achieved in all 22 patients. Fifteen patients were followed up for 6 to 24 months and exhibited good nasal shape, repaired alveolar cleft, improved labial shape, and closed oronasal fistula. Three patients presented with red nasal tips. One patient had local infection, which was cured by antibiotics. CONCLUSION: This methodAs this method has led to positive outcomes, it has the potential to be widely used in clinical practice.
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Fenda Labial/cirurgia , Cartilagem Costal/transplante , Costelas/cirurgia , Adulto , Fissura Palatina/cirurgia , Feminino , Humanos , Masculino , Nariz/cirurgia , Doenças Nasais/cirurgia , Projetos de Pesquisa , Rinoplastia , Transplante Autólogo , Adulto JovemRESUMO
The Sichuan snub-nosed monkey (Rhinopithecus roxellana) is an endangered species endemic to China, where the smallest population resides in Shennongjia National Park, Hubei Province. In this study, the genetic diversity of the Sichuan snub-nosed monkeys from two areas, Qianjiaping (QJP) and Dalongtan (DLT) in Shennongjia National Park was evaluated using single nucleotide polymorphisms (SNPs) data derived from restriction site-associated DNA sequencing (RAD-seq). A total of 41,260 SNP loci were found in 29 Sichuan snub-nosed monkey individuals. The genome-wide nucleotide diversity (π) of the Shennongjia population was 0.001842. The genetic differentiation (FST) between the QJP and DLT subpopulations was 0.034. The heterozygosity of individuals from QJP was 0.3475 ± 0.03696 and 0.3148 ± 0.03501 for individuals from DLT. Although the DLT and QJP subpopulations did not show significant genetic differences, genetic differentiation between the two subpopulations was confirmed using Bayesian cluster analysis, neighbor-joining trees and principal component analysis. These results suggest that the Shennongjia population of Sichuan snub-nosed monkey has relatively low genetic diversity at the genomic level. The little genetic differentiation noted between the DLT and QJP subpopulations likely due to natural and anthropogenic barriers which may exacerbate loss of genetic diversity of this endangered subpopulation.
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Variação Genética , Presbytini/genética , Animais , Teorema de Bayes , China , Espécies em Perigo de Extinção , Feminino , Masculino , Parques Recreativos , Filogenia , Polimorfismo de Nucleotídeo Único , População/genética , Análise de Sequência de DNARESUMO
It is necessary to study the mechanism of resistance to heavy metals in microbiological processes. In this study, Ochrobactrum MT180101 was used as the microbial source of an membrane bioreactor to investigate its degradation efficiency for electroplating wastewater and the copper-resistant mechanism. Meanwhile, excitation emission matrix-parallel factor, scanning electron microscope, atomic force microscope, fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and proteome analyses were applied to explain the comprehensive mechanism of the Ochrobactrum MT180101 resisting heavy metal toxicity. The results indicated that the Ochrobactrum MT180101 resisted heavy metal toxicity with the following pathways: i) binding metal cations on cell wall surfaces, ii) generating microbial products such as protein to chelate and stabilize the metal cations, iii) bio-transporting heavy metals from the intramembrane to the outer membrane by means of intracellular transport, and iv) reducing heavy metals through enzyme-mediated biotransformation. The results ensure that Ochrobactrum MT180101 was a copper-resistant bacterium that can be used in the pretreatment or deep treatment of electroplating wastewater.
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Reatores Biológicos/microbiologia , Cobre/metabolismo , Galvanoplastia , Ochrobactrum/metabolismo , Transporte Biológico/fisiologia , Membranas Artificiais , Metais Pesados/metabolismo , Espectroscopia Fotoeletrônica , Eliminação de Resíduos Líquidos , Gerenciamento de Resíduos/métodos , Águas Residuárias/química , Águas Residuárias/toxicidadeRESUMO
BACKGROUND: Underdevelopment of nose and chin in East Asians is quite common. Rhinoplasty and mentoplasty are effective procedures to solve the above-depicted defects and can achieve remarkable cosmetic effects. An autologous costal cartilage graft has become an ideal material for rhinoplasty, especially for revision surgery. However, many problems in the clinical application of costal cartilage remain unresolved. This study is to investigate application strategies of autologous costal cartilage grafts in rhino- and mentoplasty. METHODS: The methods involved are as follows: application of an integrated cartilage scaffold; comprehensive application of diced cartilage; and chin augmentation of an autologous costal cartilage graft. RESULTS: In this study, satisfactory facial contour appearance was immediately achieved in 28 patients after surgery; 21 patients had satisfactory appearance of the nose and chin during the 6- to 18-month follow-up. Cartilage resorption was not observed. Two patients had nasal tip skin redness and were cured after treatment. CONCLUSION: This procedure can be used to effectively solve: curvature of the costal cartilage segment itself; warping of the carved costal cartilage; and effective use of the costal cartilage segment. The procedure has achieved satisfactory outcomes, and its application is worth extending to clinical practice.
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Cartilagem Costal/transplante , Mentoplastia , Rinoplastia , Adolescente , Adulto , Autoenxertos/cirurgia , Queixo/cirurgia , Feminino , Humanos , Nariz/cirurgia , Adulto JovemRESUMO
To study the biosorption behaviors of bacteria on heavy metal chelators, the biosorption kinetics, biosorption thermodynamics and pH influence tests of the Ochrobactrum MT180101 on ionic and chelate copper were investigated. Furthermore, the biosorption mechanisms of the Ochrobactrum MT180101 on ionic copper and chelate copper were explained by means of an excitation emission matrix as well as infrared and X-ray photoelectron spectroscopy. The results indicated the following. 1) The biosorption on chelate copper was needed to destroy the complexation group first through metabolic and secretory activities. 2) The biosorption mechanism of the Ochrobactrum MT180101 on copper involved surface biosorption, extracellular chelation and bienzyme-mediated biotransformation. The results suggested that Ochrobactrum had a superior biosorption efficiency to ionic and chelate copper.
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Metais Pesados , Ochrobactrum , Adsorção , Cobre , Concentração de Íons de Hidrogênio , Íons , CinéticaRESUMO
Climate is predicted to change over the 21st century. However, little is known about how climate change can affect soil phosphorus (P) cycle and availability in global terrestrial ecosystems, where P is a key limiting nutrient. With a global database of Hedley P fractions and key-associated physiochemical properties of 760 (seminatural) natural soils compiled from 96 published studies, this study evaluated how climate pattern affected soil P cycle and availability in global terrestrial ecosystems. Overall, soil available P, indexed by Hedley labile inorganic P fraction, significantly decreased with increasing mean annual temperature (MAT) and precipitation (MAP). Hypothesis-oriented path model analysis suggests that MAT negatively affected soil available P mainly by decreasing soil organic P and primary mineral P and increasing soil sand content. MAP negatively affected soil available P both directly and indirectly through decreasing soil primary mineral P; however, these negative effects were offset by the positive effects of MAP on soil organic P and fine soil particles, resulting in a relatively minor total MAP effect on soil available P. As aridity degree was mainly determined by MAP, aridity also had a relatively minor total effect on soil available P. These global patterns generally hold true irrespective of soil depth (≤10 cm or >10 cm) or site aridity index (≤1.0 or >1.0), and were also true for the low-sand (≤50%) soils. In contrast, available P of the high-sand (>50%) soils was positively affected by MAT and aridity and negatively affected by MAP. Our results suggest that temperature and precipitation have contrasting effects on soil P availability and can interact with soil particle size to control soil P availability.
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Mudança Climática , Fósforo/análise , Solo/química , Clima , Ecossistema , Umidade , Modelos Teóricos , Chuva , TemperaturaRESUMO
We present the design and experimental demonstration of the ultra-high-Q-factor silicon microring resonator based on a multi-mode ridge waveguide. The multi-mode ridge waveguide is designed to decrease the propagation loss and to improve the Q factor. The ultra-high Q factor of 1.1×106 is experimentally demonstrated, with the free spectrum range of 0.208 nm. The single-mode ridge waveguide is used in the coupling region to reduce the dimension of the microring resonator, and the bend radius is only 20 µm. To precisely control the resonance wavelength, a small heater is implemented on the silicon microring resonator with the tuning efficiency of 7.1 pm/mW. The degenerate four-wave mixing of the silicon microring resonator is investigated, and the conversion efficiency is measured to be -15.5 dB without optimizing the dispersion of the microring resonator and carriers extraction.