RESUMO
BACKGROUND: It is proposed a new running suture technique called Needle Adjustment Free (NAF) technique, or PAN suture. The efficiency and the safety were evaluated in laparoscopic partial nephrectomy. METHODS: This new running suture technique avoids the Needle Adjustment method used in traditional techniques. The new continuous suture technique (11 patients) was compared with the traditional continuous suture method (33 patients) used in both transperitoneal and retroperitoneal laparoscopic partial nephrectomy (LPN) in terms of suture time (ST), warm ischemia time (WIT), blood loss (BL), open conversion rate and post-op discharge time, post-op bleeding, post-op DVT, ΔGFR (affected side, 3 months post-op). Differences were considered significant when P < 0.05. RESULTS: ST in the PAN suture group was 30.37 ± 16.39 min, which was significant shorter (P = 0.0011) than in the traditional technique group which was 13.68 ± 3.33 min. WIT in the traditional technique group was 28.73 ± 7.89 min, while in the PAN suture group was 20.64 ± 5.04 min, P = 0.0028. The BL in entirety in the traditional technique group was 141.56 ± 155.23 mL, and in the PAN suture group was 43.18 ± 31.17 mL (P = 0.0017). BL in patients without massive bleeding in the traditional technique group was significantly greater than in the PAN suture group at 101.03 ± 68.73 mL versus 43.18 ± 31.17 mL (P = 0.0008). The open conversion rate was 0 % in both groups. There was no significant difference between the two groups in postoperative discharge time, post-op bleeding, post-op DVT, ΔGFR (affected side, 3 months post-op). CONCLUSIONS: The NAF running suture technique, or PAN suture, leading to less ST, WIT and BL, which was shown to be more effective and safer than the traditional technique used for LPN. A further expanded research with larger sample size is needed.
Assuntos
Laparoscopia , Nefrectomia , Técnicas de Sutura , Humanos , Nefrectomia/métodos , Resultado do TratamentoRESUMO
High-index dielectric metasurfaces are rarely reported around 0.1-0.3 THz, as an extremely large etching depth is needed according to the millimeter-scale wavelength. In this work, we propose an easy solution to sub-THz wideband polarization control by utilizing 3D-printed low-index (n~1.5) metagratings. The metagrating with subwavelength lattice is shown as a very efficient half-wave plate (net polarization conversion of 87%) at 0.14 THz but showing noisy spectrum. The design with superwavelength lattice offers a smooth and wide bandwidth for linear polarization rotation. Study of the mechanism shows that the lattice size slightly above wavelength is a better choice for the low-index metadevice as it maintains high efficiency in the zero diffraction order and wide bandwidth due to the small mode dispersion. Such designs offer a feasible solution especially suitable for sub-THz polarization and phase control, complementary to the existing high-index dielectric and metallic metasurfaces.
RESUMO
Developing the broadband controllable or tunable terahertz (THz) polarization and phase devices are in an urgent need. In this paper, we demonstrate a broadband controllable THz quarter-wave plate (QWP) with double layers of graphene grating and a layer of liquid crystals. The double layer graphene gratings can achieve a switchable QWP to switch between linear-to-linear and linear-to-circular polarization states with over 0.35THz bandwidth in the ON or OFF state by applying biased electric field on the graphene grating or not. Moreover, this QWP based on the structure of periodic gradient grating can significantly enhance the phase difference between two orthogonally polarized components compared to that based on equal-periodic grating structure because of the additional phase distribution of the gradient structures. Furthermore, we incorporate liquid crystals into the graphene grating to form a tunable QWP, of which operating frequency can be continuously tuned in a wide frequency range by electrically controlling the molecular director of the liquid crystals. The results show that the graphene periodic gradient grating with LCs not only broadens the operating bandwidth, but also reduces the external electric field. This device offers a further step in the development of THz polarization and phase devices for potential applications in THz polarized imaging, spectroscopy, and communication.
RESUMO
In this work, the optically anisotropic property of dual-frequency liquid crystals (DFLC) in terahertz (THz) regime has been experimentally investigated, which indicates that the refractive index and birefringence of DFLC can be continuously modulated by both the alternating frequency and intensity of the alternating electric field. This tunability originates from the rotation of DFLC molecules induced by alternating electric fields. The results show that by modulating the alternating frequency from 1 kHz to 100 kHz under 30 kV/m electric field, the 600 µm thickness DFLC cell can play as a tunable quarter-wave plate above 0.68 THz, or a half-wave plate above 1.33 THz. Besides, it can be viewed as a tunable THz phase shifter from 0 to π. Therefore, due to its novel tuning mechanism, DFLC will be of great significance in dynamic manipulating on THz phase and polarization.
RESUMO
Mycophenolate mofetil (MMF) is an important immunosuppressant used in renal transplantation, and mycophenolic acid (MPA) is the active component released from the ester prodrug MMF. The objective of this study was to investigate the population pharmacokinetics of mycophenolic acid (MPA) following oral administration of MMF in Chinese adult renal transplant recipients and to identify factors that explain MPA pharmacokinetic variability. Pharmacokinetic data for MPA and covariate information were retrospectively collected from 118 patients (79 patients were assigned to the group for building the population pharmacokinetic model, while 39 patients were assigned to the validation group). Population pharmacokinetic data analysis was performed using the NONMEM software. The pharmacokinetics of MPA was best described by a two-compartment model with a first-order absorption rate with no lag time. Body weight and serum creatinine level were positively correlated with apparent clearance (CL/F). The polymorphism in uridine diphosphate glucuronosyltransferase gene, UGT2B7, significantly explained the interindividual variability in the initial volume of distribution (V1/F). The estimated population parameters (and interindividual variability) were CL/F 18.3 L/h (34.2%) and V1/F 27.9 L (21.3%). The interoccasion variability was 13.7%. These population pharmacokinetic data have significant clinical value for the individualization of MMF therapy in Chinese adult renal transplant patients.
Assuntos
Imunossupressores/farmacocinética , Transplante de Rim , Modelos Biológicos , Ácido Micofenólico/farmacocinética , Administração Oral , Adolescente , Adulto , Idoso , Povo Asiático , Teorema de Bayes , China , Feminino , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/sangue , Absorção Intestinal , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Ácido Micofenólico/administração & dosagem , Ácido Micofenólico/sangue , Variantes Farmacogenômicos , Estudos Retrospectivos , Adulto JovemRESUMO
In this work, we investigate the nonreciprocal circular dichroism for terahertz (THz) waves in magnetized InSb by the theoretical calculation and numerical simulation, which indicates that longitudinally magnetized InSb can be applied to the circular polarizer and nonreciprocal one-way transmission for the circular polarization THz waves. Furthermore, we propose a double-layer magnetoplasmonics based on the longitudinally magnetized InSb, and find two MO enhancement mechanisms in this device: the magneto surface plasmon resonance on the InSb-metal surface and Fabry-Pérot resonances between two orthogonal metallic gratings. These two resonance mechanisms enlarge the MO polarization rotation and greatly reduce the external magnetic field below 0.1T. The one-way transmission and perfect linear polarization conversion can be realized over 70dB, of which the transmittance can be modulated from 0 to 80% when the weak magnetic field changes from 0 to 0.1T under the low temperature around 200K. This magnetoplasmonic device has broad potential as a THz isolator, modulator, polarization convertor, and filter in the THz application systems.
RESUMO
The destabilizing of protein leads to self-aggregation and fibrillar assemblies. In the form of amyloid fibrils or fibril precursors, protein not only lacks the original biological function but also may be harmful to organisms. Stimulated by an intense electric field, the secondary structures of protein can be disturbed and transfer to aggregations or unfolding conformations, which may inhibit the fibrillation process. As a model for disease-associated amyloids, insulin fibrillation is proposed to occur via partial unfolding of a monomeric intermediate. This project is focusing on in-vitro studies employing a 33 Hz pulsed electric field (PEF) to see if there is possible causal connection between insulin fibrillation and PEF exposure. Thioflavin T (ThT)-fluorescence, circular dichroism(CD) and transmission electron microscopy (TEM) techniques were employed regarding the effects of exposure duration and field intensity of the PEF on the fibrillation mechanism of insulin. The results confirm that the PEF exposed insulin molecules may primitively have a slight change in its native structure, causing aggregation. The aggregates in the PEF exposed insulin solution are difficult to dissolve to facilitate the unfolding of insulin molecules. When the molecular conformation converts from α-helical to ß-sheet structure, the fibrillation velocity in the PEF exposed insulin is accelerated by the PEF exposure thereby shortening the lifetime of the intermediates. The morphology of mature fibrils changes from long twisted fibrils to shorter and less matured fibrils. All these effects enhance when the exposure duration and electric intensity increase. The investigated evidences suggest that the PEF can inhibit insulin amyloidosis.
Assuntos
Amiloidose , Eletricidade , Insulina , Estrutura Secundária de Proteína , Amiloide , Benzotiazóis , Dicroísmo Circular , Fluorescência , HumanosRESUMO
A tunable metal/magneto-optic plasmonic lens for terahertz isolator is demonstrated. Based on the magneto-optical effect of the semiconductor material and non-symmetrical structure, this plasmonic lens has not only the focusing feature but also nonreciprocal transmission property. Moreover, a transmission enhancement through this device greatly larger than that of the ordinary metallic slit arrays is contributed by the extraordinary optical transmission effect of the magneto surface plasmon polaritons. The results show that the proposed isolator has an isolation bandwidth of larger than 0.4THz and the maximum isolation of higher than 110dB, and its operating frequency also can be broadly tuned by changing the external magnetic field or temperature. This low-loss, high isolation, broadband tunable nonreciprocal terahertz transmission mechanism has a great potential for terahertz application systems.
Assuntos
Lentes , Magnetismo/instrumentação , Metais/química , Refratometria/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Radiação TerahertzRESUMO
The state conversion and terahertz (THz) wave modulation based on a plasmonic device composed of silicon column arrays with vanadium dioxide (VO2) coating were experimentally demonstrated. For double 45° tilted optical pumping, a state conversion from dielectric photonic crystal (PC) to metallic PC was demonstrated due to the insulator-metal transition (IMT) of VO2 with the pump power increasing. In this process, a broadband intensity modulation with 70% modulation depth was achieved. Furthermore, for normally incident optical pumping, another state conversion from dielectric PC to plasmonic device was also demonstrated due to the partial IMT of VO2, and the out of plane PC resonance gradually changed to be plasmonic resonances. This device and its modulation scheme will be of great significance for potential THz applications.
RESUMO
OBJECTIVE: To investigate the incidence and mortality of cancer registered in Zhejiang province in 2009. METHODS: The statistics of incidence and mortality of cancer were collected from 6 population-based cancer registries in Zhejiang province, including 30 613 new incidence cases and 16 920 death cases reported in 2009. The 6 cancer registries covered population at 9 560 699 in all. The crude rate, age-standardized rate, cumulative rate (0-74 years old), cut rate (35-64 years old), age-specific rate of incidence/mortality as well as the constitution of top 10 common cancers were then calculated and analyzed. The age-standardized rate was calculated and adjusted by the Chinese standard population in 1982 as well as the Segi's world standard population. RESULTS: The crude incidence of cancer was 320.20/100 000. Age-standardized incidence by Chinese standard population and by world standard population were separately 161.99/100 000 and 207.92/100 000, the cumulative rate was 23.83% and the cut rate was 346.87/100 000. Meanwhile, the crude mortality rate was 176.97/100 000, and the age-standardized mortality by Chinese standard population and by world standard population were 79.17/100 000, 107.02/100 000, respectively; and the cumulative mortality rate was 12.23% and cut rate was 139.75/100 000. Age-specific incidence among 0-34 years old population remained low; however, the incidence among 35-39 age group increased obviously (116.46/100 000, 954 cases). The incidence among 45-49 age group elevated even more sharply (272.97/100 000, 2388 cases) and finally reached the peak among 80-84 age group (1564.36/100 000, 2272 cases). Age-specific mortality arose among 40-44 age group (48.06/100 000, 424 cases) and reached its peak among 80-84 age group (1392.23/100 000, 2022 cases) as well. The most common types of cancer were lung cancer, gastric cancer, colorectal cancer, liver cancer, breast cancer, esophageal cancer, thyroid cancer, pancreatic cancer, cervical cancer and lymphoma, which accounted for 74.37% (22 763/30 613) of all new cancer cases.Lung cancer, liver cancer, gastric cancer, colorectal cancer, esophageal cancer, pancreatic cancer, leukemia, lymphoma, brain tumors and breast cancer accounted for 87.75% (14 848/16 920) of all cancer deaths. CONCLUSION: The incidence and mortality of cancer both increased in 2009 according to the statistics from cancer registry in Zhejiang province.Lung cancer, malignant tumor in digestive system and breast cancer were still the key challenges in cancer prevention and control. Meanwhile, the increased incidence of thyroid cancer should also be noticed.
Assuntos
Neoplasias/epidemiologia , Neoplasias/mortalidade , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Distribuição por Sexo , Taxa de Sobrevida , Adulto JovemRESUMO
The efficient sensing of amino acids, especially the distinction of their chiral enantiomers, is important for biological, chemical, and pharmaceutical research. In this work, a THz phase shift sensing method was performed for amino acid detection based on a polarization-dependent electromagnetically induced transparency (EIT) metasurface. More importantly, a method for binding the specific amino acids to the functional proteins modified on the metasurface was developed based on the isoelectric point theory so that the specific recognition for Arginine (Arg) was achieved among the four different amino acids. The results show that via high-Q phase shift, the detection precision for L-Arg is 2.5 × 10-5â g /ml, much higher than traditional sensing parameters. Due to the specific electrostatic adsorption by the functionalized metasurface to L-Arg, its detection sensitivity and precision are 22 times higher than the other amino acids. Furthermore, by comparing nonfunctionalized and functionalized metasurfaces, the D- and L-chiral enantiomers of Arg were distinguished due to their different binding abilities to the functionalized metasurface. Therefore, this EIT metasurface sensor and its specific binding method improve both detection precision and specificity in THz sensing for amino acids, and it will promote the development of THz highly sensitive detection of chiral enantiomers.
RESUMO
Chirality plays an important role in biological processes, and enantiomers often possess similar physical properties and different physiological functions. Thus, chiral detection of enantiomers has become a hot topic in recent years, and methods to enhance chiral molecular recognition are in urgent demand. In this work, a polarization detection method was used for different chiral drugs based on a specially designed metasurface composed of asymmetric double-opened rings and the surface enhancement effect of gold nanoparticles (GNPs). The experiment results show that the frequency shifts caused by the nearfield interaction of the metasurface and biomolecules have been significantly improved by GNPs, and both the limit of detection and detection precision of the metasurface can reach the 10-5 g ml-1 level. Moreover, the polarization sensing characterized by right circular polarization (RCP), the polarization elliptical angle (PEA), and the polarization rotation angle (PRA) shows that the enantiomers of three drugs can be distinguished, especially using the PEA spectrum; the maximum difference between enantiomers is over 30° with a precision of 6.6 × 10-7 g mL-1. Our THz polarization sensing and the GNP enhancement method inspire an efficient strategy for the highly sensitive detection of enantiomers.
Assuntos
Ouro , Nanopartículas MetálicasRESUMO
A terahertz modulator based on the insulator-metal transition (IMT) in a photonic crystal waveguide (PCW) coated by vanadium dioxide (VO2) film is proposed. The numerical simulations show that a dielectric state and a metallic state with quite different photonic band structures and transmission properties in the proposed PCW are reciprocally converted because of the IMT of VO2, and the pass-bands of this PCW are greatly shifted from 0.68 to 0.8 and 1.02 to 1.25 THz to 0.8-1.45 THz. This PCW significantly enhances the modulation depth and sensitivity compared with bare VO2 film. Extensive investigation demonstrates that the thickness of VO2 film greatly affects the IMT process in the PCW, and limits the ultimate modulation depth of the device. The proposed modulation scheme will be of great significance for potential THz applications.
RESUMO
In the title compound, C(17)H(14)O(5)S, the coumarin ring system is nearly planar, with a maximum deviation of 0.034â (2)â Å from the mean plane. The dihedral angle between the benzene ring and the coumarin ring system is 56.11â (6)°. The crystal packing is stabilized by C-Hâ¯O hydrogen bonding, which forms a three-dimensional framework.
RESUMO
The title compound, C(14)H(11)BrN(2)OS, was synthesized by the reaction of 1,2-benzothia-zol-3(2H)-one with formalin and 3-bromo-aniline in ethanol. The 1,2-benzothia-zolone ring system is approximately planar [maximum deviation = 0.0142â (s.u.?)â Å] and forms a dihedral angle of 79.19â (5)° with the benzene ring. In the crystal, molecules are linked by N-Hâ¯O, C-Hâ¯O and C-Hâ¯Br interactions.
RESUMO
The mol-ecule of the title compound, C(12)H(12)O(2), is essentially planar, with a maximum deviation from the mean plane of all non-H atoms of 0.038â (1)â Å for the methyl C atom in the 8-position. The crystal structure is characterized by anti-parallel π-π stacking along the c axis, with centroid-centroid distances as short as 3.866â (1)â Å. In the crystal, C-Hâ¯O hydrogen bonds connect the mol-ecules across the stacks into ribbons in the a-axis direction.
RESUMO
The title compound, C(11)H(11)NO(3)S, was synthesized by the reaction of benzo[d]isothia-zol-3(2H)-one with isopropanol in toluene. The benzoisothia-zolone ring system is essentially planar, with a mean deviation of 0.018â (2)â Å from the least-squares plane defined by the nine constituent atoms. In the crystal, mol-ecules are linked by weak inter-molecular C-Hâ¯O hydrogen bonds.
RESUMO
The title compound, C(10)H(9)NO(3)S, was synthesized by the reaction of benzo[d]isothia-zol-3(2H)-one with ethyl carbonochloridate in toluol. The benzisothia-zolone ring system is approximately planar, with a maximum deviation from the mean plane of 0.020â (1)â Å for the N atom.
RESUMO
The title compound, C(11)H(11)NO(3)S, was synthesized by the reaction of benzo[d]isothia-zol-3(2H)-one with propyl carbono-chloridate in toluene. The benzoisothiazolone ring system is approximately planar with a maximum deviation from the mean plane of 0.0226â (14)â Å for the N atom. Weak inter-molecular C-Hâ¯O hydrogen bonding occurs in the crystal structure.
RESUMO
In the title compound, C(9)H(7)NO(3)S, the benzoisothia-zolone ring system is essentially planar, with a maximum deviation of 0.013â (2)â Å. In the crystal, mol-ecules are linked via O-Hâ¯O hydrogen bonds, forming chains along [010]. In addition, weak inter-molecular C-Hâ¯O hydrogen bonds are present.