135 research outputs found
Preparation of Bioactive Glasses with Controllable Degradation Behavior and Their Bioactive Characterization
Bioactive glasses and ceramics have been widely investigated for bone repair because of their excel-lent bioactive characteristics. However, these biomaterials undergo incomplete conversion into a bone-like material, which severely limits their biomedical application. In this paper, borosilicate bioac-tive glasses were prepared by traditional melting process. The results showed that borosilicate glasses possessed high biocompatibility and bioactivity. In addition, when immersed in a 0.02 mol/L K2HPO4 solution, particles of a borate glass were fully converted to HA. The desirable conversion rate to HA may be achieved through the adjustment of the B2O3/SiO2 ratio. The results of XRD and FTIR analysis indicated that the degradation product was carbonate-substituted hydroxyapatite, which was similar to the inorganic component of bone
Promising derivatives of rutaecarpine with diverse pharmacological activities
Rutaecarpine (RUT) is a natural pentacyclic indolopyridoquinazolinone alkaloid first isolated from one of the most famous traditional Chinese herbs, Evodia rutaecarpa, which is used for treating a variety of ailments, including headaches, gastrointestinal disorders, postpartum hemorrhage, amenorrhea, difficult menstruation, and other diseases. Accumulating pharmacological studies showed that RUT possesses a wide range of pharmacological effects through different mechanisms. However, its poor physicochemical properties and moderate biological activities have hampered its clinical application. In this regard, the modification of RUT aimed at seeking its derivatives with better physicochemical properties and more potency has been extensively studied. These derivatives exhibit diverse pharmacological activities, including anti-inflammatory, anti-atherogenic, anti-Alzheimer’s disease, antitumor, and antifungal activities via a variety of mechanisms, such as inhibiting cyclooxygenase-2 (COX-2), acetylcholine (AChE), phosphodiesterase 4B (PDE4B), phosphodiesterase 5 (PDE5), or topoisomerases (Topos). From this perspective, this paper provides a comprehensive description of RUT derivatives by focusing on their diverse biological activities. This review aims to give an insight into the biological activities of RUT derivatives and encourage further exploration of RUT
Influence of Ag micro-alloying on the thermal stability and ageing characteristics of a Cu–14Fe in-situ composite
This paper studied the influence of Ag micro-alloying on the thermal stability and ageing characteristics of a deformation-processed Cu–14Fe in-situ composite prepared by thermo-mechanical processing. Heat treatment caused (i) edge recession, longitudinal splitting, cylinderization, break-up and spheroidisation of the Fe fibres in the Ag micro-alloyed Cu–14Fe in-situ composite, and (ii) recovery, recrystallisation and precipitation in the Cu matrix. Ag micro-alloying caused these processes to occur at lower temperatures. The index Z (a combination figure of merit that assesses the service performance) reached the peak value of 3.3×10 MPa·% IACS after isothermal heat treatment at 500 °C for 1 h, where IACS is the International Annealed Copper Standard, a measure of conductivity. The optimum combinations of tensile strength and conductivity were 1033 MPa and 56.6% IACS; 931 MPa and 58.9% IACS; or 851 MPa and 60.6% IACS. The tensile strength and conductivity of Ag micro-alloyed Cu–14Fe in-situ composite at η=7.8 after isochronal heat treatments were higher than those of the Cu–14Fe in-situ composite at each temperature
Clinical analysis of decision implementation by a multidisciplinary team in cervical cancer cases in Ganzhou, China
ObjectiveIn this study, we evaluated the role of a multidisciplinary team (MDT) in clinical practice for cervical cancer by analyzing the development of a single-case multidisciplinary consultation for cervical cancer.MethodsPatients in MDT consultations for cervical cancer were retrospectively analyzed for clinical information, decision content of MDT discussion, implementation, and follow-up results.ResultsOf the 392 patients who met the inclusion criteria, 359 had a first episode, of which 284 were stage IA-IIA2 (79.11%) and 75 were stage IIB-IVB (20.89%). Of these 392, 33 had a recurrence (8.42%). A total of 416 cases were analyzed, and neoadjuvant chemotherapy with surgery was recommended in 43 cases, of which 40 cases were implemented, and 36 of the 40 achieved the expected outcome. Surgical treatment was recommended in 241 cases, of which 226 underwent surgery, and 215 of them achieved the expected outcome. Radiotherapy was recommended in 31 cases, of which 26 cases underwent it, and 22 of them achieved the expected efficacy. Concurrent chemoradiotherapy was recommended in 57 cases, of which 49 underwent it, and 39 of them achieved the expected efficacy. Other treatments were recommended in 44 cases, of which 23 cases were implemented, and 10 of them achieved the expected efficacy, with statistically significant differences compared with cases without implementation (P <0.05). MDT decisions were correlated with age; the younger the patients, the higher the implementation efficiency (P <0.05). The difference between MDT expectation in all implementation and partial implementation and age was statistically significant (P <0.05). No significant difference was found between age and MDT expectation in all not fully implemented decisions (P >0.05). Some decisions were not fully implemented due to economic status and fear of certain treatments of the patient.ConclusionThe MDT plays an important role in clinical practice such as clinical staging, treatment plan, and the complete treatment management of patients with cervical cancer, which can significantly improve the near-term treatment effect, whereas its effect on a long-term prognosis needs further clinical observation and active exploration
Enhanced heating rate of black carbon above planetary boundary layer over megacities in summertime
The fast development of a secondary aerosol layer was observed over megacities in eastern Asia during summertime. Within three hours, from midday to early afternoon, the contribution of secondary aerosols above the planetary boundary layer (PBL) increased by a factor of 3-5, and the coatings on the black carbon (BC) also increased and enhanced its absorption efficiency by 50%. This tended to result from the intensive actinic flux received above the PBL which promoted the photochemical reactions. The absorption of BC could be further amplified by the strong reflection of solar radiation over the cloud top across the PBL. This enhanced heating effect of BC introduced by combined processes (intensive solar radiation, secondary formation and cloud reflection) may considerably increase the temperature inversion above the PBL. This mechanism should be considered when evaluating the radiative impact of BC, especially for the polluted regions receiving strong solar radiation
Fungal diversity notes 929–1035: taxonomic and phylogenetic contributions on genera and species of fungi
This article is the ninth in the series of Fungal Diversity Notes, where 107 taxa distributed in three phyla, nine classes, 31 orders and 57 families are described and illustrated. Taxa described in the present study include 12 new genera, 74 new species, three new combinations, two reference specimens, a re-circumscription of the epitype, and 15 records of sexualasexual morph connections, new hosts and new geographical distributions. Twelve new genera comprise Brunneofusispora, Brunneomurispora, Liua, Lonicericola, Neoeutypella, Paratrimmatostroma, Parazalerion, Proliferophorum, Pseudoastrosphaeriellopsis, Septomelanconiella, Velebitea and Vicosamyces. Seventy-four new species are Agaricus memnonius, A. langensis, Aleurodiscus patagonicus, Amanita flavoalba, A. subtropicana, Amphisphaeria mangrovei, Baorangia major, Bartalinia kunmingensis, Brunneofusispora sinensis, Brunneomurispora lonicerae, Capronia camelliaeyunnanensis, Clavulina thindii, Coniochaeta simbalensis, Conlarium thailandense, Coprinus trigonosporus, Liua muriformis, Cyphellophora filicis, Cytospora ulmicola, Dacrymyces invisibilis, Dictyocheirospora metroxylonis, Distoseptispora thysanolaenae, Emericellopsis koreana, Galiicola baoshanensis, Hygrocybe lucida, Hypoxylon teeravasati, Hyweljonesia indica, Keissleriella caraganae, Lactarius olivaceopallidus, Lactifluus midnapurensis, Lembosia brigadeirensis, Leptosphaeria urticae, Lonicericola hyaloseptispora, Lophiotrema mucilaginosis, Marasmiellus bicoloripes, Marasmius indojasminodorus, Micropeltis phetchaburiensis, Mucor orantomantidis, Murilentithecium lonicerae, Neobambusicola brunnea, Neoeutypella baoshanensis, Neoroussoella heveae, Neosetophoma lonicerae, Ophiobolus malleolus, Parabambusicola thysanolaenae, Paratrimmatostroma kunmingensis, Parazalerion indica, Penicillium dokdoense, Peroneutypa mangrovei, Phaeosphaeria cycadis, Phanerochaete australosanguinea, Plectosphaerella kunmingensis, Plenodomus artemisiae, P. lijiangensis, Proliferophorum thailandicum, Pseudoastrosphaeriellopsis kaveriana, Pseudohelicomyces menglunicus, Pseudoplagiostoma mangiferae, Robillarda mangiferae, Roussoella elaeicola, Russula choptae, R. uttarakhandia, Septomelanconiella thailandica, Spencermartinsia acericola, Sphaerellopsis isthmospora, Thozetella lithocarpi, Trechispora echinospora, Tremellochaete atlantica, Trichoderma koreanum, T. pinicola, T. rugulosum, Velebitea chrysotexta, Vicosamyces venturisporus, Wojnowiciella kunmingensis and Zopfiella indica. Three new combinations are Baorangia rufomaculata, Lanmaoa pallidorosea and Wojnowiciella rosicola. The reference specimens of Canalisporium kenyense and Tamsiniella labiosa are designated. The epitype of Sarcopeziza sicula is re-circumscribed based on cyto- and histochemical analyses. The sexual-asexual morph connection of Plenodomus sinensis is reported from ferns and Cirsium for the first time. In addition, the new host records and country records are Amanita altipes, A. melleialba, Amarenomyces dactylidis, Chaetosphaeria panamensis, Coniella vitis, Coprinopsis kubickae, Dothiorella sarmentorum, Leptobacillium leptobactrum var. calidus, Muyocopron lithocarpi, Neoroussoella solani, Periconia cortaderiae, Phragmocamarosporium hederae, Sphaerellopsis paraphysata and Sphaeropsis eucalypticola
Case studies of electrical characterisation of graphene by terahertz time-domain spectroscopy
Graphene metrology needs to keep up with the fast pace of developments in graphene growth and transfer. Terahertz time-domain spectroscopy (THz-TDS) is a non-contact, fast, and non-destructive characterization technique for mapping the electrical properties of graphene. Here we show several case studies of graphene characterization on a range of different substrates that highlight the versatility of THz-TDS measurements and its relevance for process optimization in graphene production scenarios
Recommended from our members
Design Techniques for Timing Circuits in Wireline and Wireless Communication Systems
Clock and data recovery (CDR) circuit and frequency synthesizer are two essential timing circuits in wireline and wireless communication systems, respectively. With multigigabits/s high speed links and emerging 4G wireless system widely used in communication backbone infrastructures and consumer electronic devices, effective design of CDR and frequency synthesizer has become more and more important. The advanced scaled-down CMOS process has the limitations of leakage current, low supply voltage and process variation which pose great challenge to the analog circuit design. To overcome these issues, a digital intensive CDR solution is needed. Besides, it is desirable for the CDR to cover a wide range of data-rate and to be reference-less for improved flexibility. As for the frequency synthesizer design, the support for multi-standard to reduce the cost and area is desirable. In this work, a digital reference-less CDR is proposed to support continuous datarate ranging from 1 Gbps to 16 Gbps. The CDR adopts an 8 GHz~16 GHz DCO to achieve low random noise performance. A reference-less digital frequency locking loop is included in the system as the acquisition assistance for the CDR loop. To address the difficulty of jitter and stability evaluations for bang-band CDR, a Simulink model is developed to find out the jitter transfer (JTRAN), jitter generation (JGEN) and jitter tolerance (JTOL) performances for the CDR. The prototype CDR is implemented in a 65 nm CMOS process. The core area is 0.68 mm². At 16 Gbps, the CDR consumes a power of 92.5 mW and is able to tolerate a sinusoidal jitter with an amplitude of 0.4 UI and a frequency of 4 MHz. The second part of this dissertation develops a frequency synthesizer for multistandard wireless receivers. The frequency synthesizer is based on an analog fractional-N PLL. Optimally-coupled quadrature voltage-controlled-oscillator (QVCO), dividers and harmonic rejection single sideband mixer (HR-SSBmixer) are combined to synthesize the desired frequency range without posing much phase noise penalty on the QVCO. The QVCO adopts a new phase-shift scheme to improve phase noise and to eliminate bimodal oscillation. Combining harmonic rejection and single sideband mixing, the HR-SSBmixer is developed to suppress spurious signals. Designed in a 0.13-μm CMOS technology, the synthesizer occupies an active area of 1.86 mm² and consumes 35.6 to 52.62 mW of power. Measurement results show that the synthesizer frequency range, the phase noise, the settling time and the spur performances meet the specifications of the wireless receivers for the above standards. For a wide range frequency synthesizer, an automatic frequency calibration circuit (AFC) is needed to select proper oscillator tuning curve before the PLL settling. An improved counter-based AFC is proposed in this dissertation that provides a more robust and faster tuning curve searching process. The proposed AFC adopts a time-to-digital converter (TDC), which is able to captures the fractional VCO cycle information within the counting window, to improve the AFC frequency detection accuracy. The TDC-based AFC is designed in a 0.13-μm CMOS technology. Simulation results show that the TDCbased AFC greatly improves the frequency detection accuracy and consequently for a given frequency detection resolution reduces the AFC calibration time.Release after 19-Dec-201
- …