RESUMEN
The elution of pharmaceutical products such as metformin at higher concentrations than the safe level in aquatic systems is a serious threat to human health and the ecosystem. Photocatalytic technology using TiO2 semiconductors potentially fixes this problem. This study aims to synthesize triphasic anatase-rutile-brookite TiO2 using ultrasound assisted sol-gel technique in the presence of acid and its application to photodegradation of metformin under UV light irradiation. Based on X-ray diffraction analysis, a TiO2 sample consisted of anatase (76%), rutile (7%), and brookite (17%) polymorph (A76R7B17) that was fully crystallized. Scanning electron microscopy (EM)-energy dispersive X-ray spectra results showed agglomerated triphasic A76R7B17 with irregular spherical clusters. Transmission EM results revealed that the crystal size of A76R7B17 was 4-14 nm. The Brunauer-Emmett-Teller analysis showed the sample's specific surface area of 149 m2 g-1. The degradation test of metformin demonstrated that the A76R7B17 exhibited a 75.4% degradation efficiency after 120 min under UV light irradiation, significantly higher than using biphasic and single-phase TiO2 photocatalysts. This difference could be attributed to the heterojunction effect of triphasic materials that effectively reduced electron-hole recombination rate as well as the combination of effective electron transfer from conduction band of brookite and anatase and the utilization of wider range of UV-visible light using rutile.
Asunto(s)
Ecosistema , Luz , Humanos , Rayos Ultravioleta , Titanio/químicaRESUMEN
Transmission measurements of the soft X-ray beamline to the Small Quantum Systems (SQS) scientific instrument at the SASE3 undulator of European XFEL are presented. Measurements are reported for a wide range of photon energies (650â eV to 2400â eV), using X-ray gas monitors as well as a bolometric radiometer. The results are in good agreement with simulations for the beam transport and show a transmission of up to 80% over the whole photon energy range. The contribution of second- and third-harmonic radiation of the soft X-ray undulator is determined at selected photon energies by performing transmission measurements using a gas absorber to provide variable attenuation of the incoming photon flux. A comparison of the results with semi-analytic calculations for the generation of free-electron laser pulses in the SASE3 undulator reveals an influence of apertures along the beam transport on the exact harmonic content to be accounted for at the experiment. The second-harmonic content is measured to be in the range of 0.1% to 0.3%, while the third-harmonic contributed a few percent to the SASE3 emission. For experiments at the SQS instrument, these numbers can be reduced through specific selections of the mirror reflection angles.
Asunto(s)
Rayos Láser , Sincrotrones , Rayos X , Radiografía , FotonesRESUMEN
The International System of Units (SI) is recommended for the practical system of units of measurement. The decision of redefining the seven base units of the SI (the second, the meter, the kilogram, the ampere, the kelvin, the mole and the candela) was made at the 26th meeting of the General Conference on Weights and Measures on 16 November 2018. This redefinition came into force starting 20 May 2019, and it became a big historic turning point for the metrology society. This is because the kilogram, the unit of mass, was defined only by an artifact as the international prototype of the kilogram, has been kept for 130 years since its determination in 1889, and was finally changed to the new definition by taking the fixed numerical value of the Planck constant on that day.It is easily imagined that the redefinition of the SI base units has a strong impact on our daily life or the field of science. The reason why the SI redefinition had to be adapted is introduced firstly. Then, how the new definitions are applied now after a year from the redefinition and future prospective of the new definitions are discussed. In the last, the impacts of the SI redefinition in the field of the ionizing radiation, especially in the fields of the medical application of the ionizing radiation, are discussed.
Asunto(s)
Sistema Internacional de Unidades , Radiación IonizanteRESUMEN
HYPOTHESIS: Novel photoresponsive hybrid surfactants, in which a combination of perfluoroalkyl and alkyl chains and cationic head groups are connected via azobenzene moieties, are excellent candidates for assembling low-molecular-weight organogels (LMOGs) with reversibly switchable viscoelasticities triggered by external stimuli. EXPERIMENTS: The structure-composition-property relationships of gels assembled with the hybrid surfactants were investigated by UV-vis and NMR spectroscopy, SEM, XRD, and rheology. FINDINGS: Hybrid surfactants containing perfluorohexyl chains with more than six carbons gelled in a variety of organic solvents at concentrations of less than a few percent. In particular, compositions with the perfluorooctyl and somewhat shorter hydrocarbon chains (C1-C4) gelled in both organic solvents and water. The gellable solvent species can be well grouped according to their solubility parameters, suggesting that gelation properties can be predicted from the chemical structure of the surfactant. Mechanical and structural investigations revealed that gel viscoelasticity can be reversibly altered by applying photo, shear, and heat stimuli, which is achieved through the formation and deformation of lamella-like molecular aggregates. The multi-responsive gelation and facile molecular design of the present hybrid surfactants will expand the fields in which fluorinated LMOGs can be applied.
RESUMEN
HYPOTHESIS: Hybrid surfactants containing both alkyl and fluoroalkyl chains within the same molecule where modification of the azobenzene group will enable us to switch the superhydrophobic nature with an external light source, and the optical behavior will vary depending on the structure of the hydrophobic chains. EXPERIMENTS: Surface activity and its optically-induced variation of the azobenzene-modified hybrid surfactants were characterized using the surface tensiometry, UV-vis and NMR spectroscopy and theoretical calculation. FINDINGS: The hybrid surfactants are superhydrophobic in nature reducing the surface tension of water to near 20 mN/m. Photo-isomerization of the azobenzene group induces a drastic surface tension variation (Δγ), and particularly the compositions containing the octyl-fluorocarbon chain exhibit remarkable Δγ as much as 30 mN/m which is even higher than that of the conventional surfactants (Δγ ≈ 14-20 mN/m). Theoretical calculation suggests significantly higher hydrophilicity of the cis isomer, causing the drastic switch in the surface activity. These results indicate the promise of the hybrid surfactants as efficient surface/interface manipulators.
RESUMEN
Carbon 1s photoelectron angular distributions of an iodomethane molecule were measured relative to the recoil-frame determined by the momentum correlation between I+ and CH3 + at photoelectron energies of 3, 6.1, and 12 eV. The energy dependent behavior of the recoil-frame photoelectron angular distributions is reproduced reasonably well by the time-dependent density functional theory with B-spline methods. We discuss potential applications of the fully differential photoelectron angular distribution measurements in the molecular frame to three-dimensional molecular structural determinations identifying the directions and lengths of the bonds.
RESUMEN
The pathological assessment of the resection margin of rectal cancer is important to predict clinical outcome. The transverse slicing method of rectal specimens is recommended in Western countries. However, in Japan the longitudinal slicing method is traditionally advocated. The aim of this study was to assess the advantages of the longitudinal slicing method. The subjects were 197 consecutive patients with primary rectal cancer who underwent curative intersphincteric resection from 2000 to 2013. The resected rectal specimens were cut into 12 slices in the direction of the long axis. Resection margin was considered positive when it was less than or equal to 1 mm. Resection margin was positive in 23 patients (12%). They were classified into two groups, namely the DEEP group (n = 16, 70%), when the resection margin corresponded to the deepest tumor invasion area, and the ENTRY group (n = 7, 30%), when resection margin was around the initial cutting point of the anal canal. It was shown that resection margin tends to be positive not only in the deepest tumor invasion area but also in the entry area of the anal canal. The longitudinal slicing method may have some advantages for accurate assessment of resection margin especially in low-lying rectal cancer.
Asunto(s)
Proctectomía/métodos , Neoplasias del Recto/cirugía , Recto/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Japón , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Neoplasias del Recto/patología , Recto/cirugía , Resultado del TratamientoRESUMEN
The molecular-frame photoelectron angular distributions (MFPADs) in O 1s photoemission from CO2 molecule were measured. Patterns due to photoelectron diffractions were observed in the MFPADs. The polarization-averaged MFPADs were compared with theoretical calculation and were found to be useful in determining the molecular bond-length, which is a component to determine molecular structures.
RESUMEN
X-ray free-electron lasers provide intense pulses of coherent X-rays with a short pulse duration. These sources are chaotic by nature and therefore, to be used at their full potential, require that every X-ray pulse is characterized in terms of various relevant properties such as intensity, photon energy, position and timing. Diagnostics are for example installed on an X-ray beamline to specifically monitor the intensity of individual X-ray pulses. To date, these can however only provide a single-shot value of the relative number of photons per shot. Here are reported measurements made in January 2015 of the absolute number of photons in the hard X-ray regime at LCLS which is typically 3.5â ×â 1011â photons shot-1 between 6 and 9.5â keV at the X-ray Pump-Probe instrument. Moreover, an average transmission of â62% of the hard X-ray beamline over this energy range is measured and the third-harmonic content of â0.47% below 9â keV is characterized.
RESUMEN
Pain in athletes is ideally treated without systemic medicine. Therefore, complementary and alternative medicine, including patch treatments, is often used. The physiologic mechanisms of pain relief produced by patch treatment, however, are not well elucidated. In the present study, we introduce a pyramidal thorn (PT) patch that we developed, demonstrate the effects of this PT patch for the treatment of various types of pain in 300 subjects, and suggest a physiologic mechanism for the pain relief effects. One treatment with the PT patch effectively relieved pain in almost half the subjects evaluated. Except for pain generated deeply under the skin, such as low-back pain, pain was eliminated within four treatments with the PT patch in almost all of the subjects. Interestingly, the pain-sensing region moved along the nerve fibers after each trial. Further, patches without PT also provided some pain relief. We considered that this effect was due to hair deflection on the skin; that is, adhesion of the PT patch activates Merkel cells directly as well as Merkel cell-neurite complexes around the hair follicles by deflecting the hair follicles, whereas adhesion of a patch without PT only activates the Merkel cell-neurite complexes. In any case, patch adhesion stimulates Aß fibers to alleviate pain. Finally, we found that the pain threshold is increased by electric stimulation, suggesting that the gentle adhesion of a PT patch would be more effective. To our knowledge, this is the first study to demonstrate physiologically the validity of an adherent patch for pain relief.
Asunto(s)
Adhesivos/uso terapéutico , Atletas , Dolor/tratamiento farmacológico , Adulto , Analgesia , Estimulación Eléctrica , Femenino , Humanos , Masculino , Dolor/fisiopatología , Umbral del Dolor , DeportesRESUMEN
Hexanuclear tantalum bromide cluster units [{Ta6Bri12}La6] (i = inner, a = apical, L = ligand OH or H2O) are embedded into SiO2 nanoparticles by a reverse microemulsion (RM) based method. [{Ta6Bri12}Bra2 (H2O)a4]·nH2O (noted TBH) and tetraethyl orthosilicate (TEOS) are used as the starting cluster compound and the precursor of SiO2, respectively. The RM system in this study consists of the n-heptane (oil phase), Brij L4 (surfactants), ethanol, TEOS, ammonia solution and TBH aqueous sol. The size and morphology of the product namely {Ta6Br12}@SiO2 nanoparticles are analyzed by HAADF-STEM and EDS mappings. The presence and integrity of {Ta6Br12} in the SiO2 nanoparticles are evidenced by EDS mapping, ICP-OES/IC and XPS analysis. The optical properties of {Ta6Br12}@SiO2 nanoparticles are analyzed by diffuse reflectance UV-vis spectroscopy, further evidencing the integrity of the embedded {Ta6Br12} and revealing their oxidation state. Both {Ta6Br12}2+ and {Ta6Br12}3+ are found in SiO2 nanoparticles, but the latter is much more stable than the former. The by-products in this RM-based synthesis, as well as their related factors, are also discussed.
RESUMEN
Although pain is indispensable for survival, chronic pain places a heavy burden on humans. As the efficacy of opioid treatment is limited, the development of alternative methods of pain relief without medication is desirable. Recently, we have developed a novel method of physical analgesia using an adhesive "pyramidal thorn patch." When we apply about 3 trials of these patches on the skin of a pain region, the pain region moves toward the spinal cord like a "cutaneous rabbit," and finally, the pain vanishes. In the present review, we propose a molecular mechanism for this analgesic method or pain relief following application of the pyramidal thorn patch where firstly the mechanoreceptors and their related nerves under the skin are activated in response to touch. Transient receptor potential (TRP) channels serve as mechanosensitive channels within these mechanoreceptors. We further propose that activation of the nerves connected with the mechanoreceptors releases oxytocin, which has an antinociceptive function and activates TRP channels to hyperpolarize the pain signal nerves. We believe that our system will pave the way for alternative pain treatment.
Asunto(s)
Analgesia/métodos , Dolor Crónico/fisiopatología , Manejo del Dolor/métodos , Dimensión del Dolor/métodos , Analgesia/tendencias , Animales , Dolor Crónico/metabolismo , Humanos , Canales de Potencial de Receptor Transitorio/fisiologíaRESUMEN
PURPOSE: Anastomotic leakage after low anterior resection for rectal cancer is a critical problem. Many risk factors have been suggested and surgical techniques have improved, but anastomotic leakage remains a major postoperative challenge. This study sought to create a nomogram for precise prediction of anastomotic leakage after low anterior resection for rectal cancer. METHODS: We used data of 936 patients that had been prospectively collected by the Japanese Society for Colon and Rectal Cancer between June 2010 and February 2013. Risk factors for anastomotic leakage were identified by multivariate logistic regression analysis and used to create a nomogram. The performance of the nomogram was evaluated by using a bootstrapped-concordance index and calibration plots. RESULTS: Sex, preoperative serum albumin, tumor location and diameter, and simultaneous resection of other organs were identified as significantly associated factors that could be combined for accurate prediction of anastomotic leakage. We created a nomogram for anastomotic leakage by using these risk factors. The area under the curve was 0.72 (95% confidence interval 0.67-0.76). The nomogram had a bootstrapped-concordance index of 0.72 and was well calibrated. CONCLUSIONS: Our nomogram was a useful tool for precise prediction of anastomotic leakage after low anterior resection for rectal cancer.
Asunto(s)
Fuga Anastomótica/etiología , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Nomogramas , Neoplasias del Recto/cirugía , Anciano , Anciano de 80 o más Años , Calibración , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROCAsunto(s)
Neoplasias Colorrectales , Neoplasias Pulmonares , Metastasectomía , Humanos , Pronóstico , Factores de RiesgoRESUMEN
A reliable diagnostic device for free-electron lasers (FELs) is essential for both users and the evaluation of FEL sources and beamline optics. Here, we propose a compact bolometric radiometer (CBR) that can operate at room temperature. The CBR is mainly designed for FELs in the wavelength range from the extreme-ultraviolet (EUV) to x-rays; moreover, we confirmed that the proposed device can also be applied to synchrotron radiation. As an application of the CBR, we evaluated an FEL beamline transmission by means of bolometric technique in the EUV range for the first time, to the best of our knowledge. This indicates that the CBR is an effective diagnostic device for FELs.
RESUMEN
BACKGROUND: After treatment with local excision for TNM stage I low rectal cancer, the risk of local recurrence is not only high for T2 lesions but also for T1 lesions with features of massive invasion to the submucosal layer and/or lymphovascular invasion. OBJECTIVE: The purpose of this study was to determine the efficacy of chemoradiotherapy combined with local excision in the treatment of T1 to T2 low rectal cancer. DESIGN: We conducted a prospective, single-arm, phase II trial. SETTINGS: This was a multicenter study. PATIENTS: From April 2003 to October 2010, 57 patients were treated with local excision after additional external beam irradiation (45 Gy) plus continuous 5-week intravenous injection of 5-fluorouracil (250 mg/m per day) at 10 domestic hospitals. Fifty-three patients had clinical T1N0 lesions, and 4 had T2N0 lesions in the low rectum, located below the peritoneal reflection. MAIN OUTCOMES MEASURES: The primary end point was disease-free survival at 5 years. RESULTS: The completion rate for full-dose chemoradiotherapy was 86% (49/57). Serious, nontransient treatment-related complications were not reported. With a median follow-up of 7.3 years after local excision, the 5-year disease-free survival rate was 94% for the 53 patients with T1 lesions and 75% for the 4 patients with T2 lesions. There were 2 local recurrences during the entire observation period. Anal function after local excision and chemoradiation were kept at almost the same levels as observed before treatment. LIMITATIONS: The study was limited by the small number of registered T2 rectal cancers, retrospective evaluations of quality of life, and the exclusion of poorly differentiated adenocarcinoma (a high-risk feature of T1 lesions). CONCLUSIONS: The addition of chemoradiotherapy to local excision of T1 rectal adenocarcinomas with poor prognostic features including deep submucosal invasion and lymphovascular invasion could improve on less favorable historic oncologic outcomes of local excision alone in this high-risk group for lymph node metastasis. See Video Abstract at http://links.lww.com/DCR/A421.
Asunto(s)
Adenocarcinoma , Quimioradioterapia Adyuvante , Colectomía , Fluorouracilo/uso terapéutico , Recurrencia Local de Neoplasia/prevención & control , Neoplasias del Recto , Recto , Adenocarcinoma/epidemiología , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Adulto , Anciano , Antimetabolitos Antineoplásicos/uso terapéutico , Quimioradioterapia Adyuvante/efectos adversos , Quimioradioterapia Adyuvante/métodos , Quimioradioterapia Adyuvante/estadística & datos numéricos , Colectomía/efectos adversos , Colectomía/métodos , Colectomía/estadística & datos numéricos , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Pronóstico , Neoplasias del Recto/epidemiología , Neoplasias del Recto/patología , Neoplasias del Recto/cirugía , Recto/patología , Recto/cirugía , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
The electronic and crystal structures of Cs2[Mo6X14] (X = Cl, Br, I) cluster-based compounds were investigated by density functional theory (DFT) simulations and experimental methods such as powder X-ray diffraction, ultraviolet-visible spectroscopy, and X-ray photoemission spectroscopy (XPS). The experimentally determined lattice parameters were in good agreement with theoretically optimized ones, indicating the usefulness of DFT calculations for the structural investigation of these clusters. The calculated band gaps of these compounds reproduced those experimentally determined by UV-vis reflectance within an error of a few tenths of an eV. Core-level XPS and effective charge analyses indicated bonding states of the halogens changed according to their sites. The XPS valence spectra were fairly well reproduced by simulations based on the projected electron density of states weighted with cross sections of Al Kα, suggesting that DFT calculations can predict the electronic properties of metal-cluster-based crystals with good accuracy.
RESUMEN
BACKGROUND/AIMS: Mechanical coloanal anastomosis (MCAA) or hand-sewn coloanal anastomosis (HCAA) are used in anus-preserving surgery for low-lying rectal cancer. Either method can be used if the lower edge of the tumor is 4-6 cm from the anal verge. The goal of this study was to evaluate differences in the anal function after MCAA or HCAA. METHODS: The subjects were 305 consecutive patients with primary rectal cancer tumors situated 4-6 cm from the anal verge who underwent curative anus-preserving surgery between 2004 and 2013. Functional assessment was performed using a questionnaire at 3, 6, 12, and 24 months after stoma closure. RESULTS: Of the 305 patients, 145 underwent MCAA and 160 underwent HCAA. The median distance of the tumor from the anal verge was 6.0 cm (range 4.0-6.0) in the MCAA group and 4.5 cm (range 4.0-6.0) in the HCAA group (p < 0.001). A total of 192 patients (73%) responded to the 1-year questionnaire. The median Wexner score was 6 (range 0-17) in the MCAA group and 11 (range 0-20) in the HCAA group (p < 0.001). CONCLUSIONS: Retention of anal function is feasible after both MCAA and HCAA. MCAA may contribute to better postoperative anal function compared to HCAA.
Asunto(s)
Canal Anal/fisiopatología , Canal Anal/cirugía , Colon/cirugía , Neoplasias del Recto/cirugía , Técnicas de Sutura , Adulto , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica/métodos , Defecación , Supervivencia sin Enfermedad , Incontinencia Fecal/etiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Tratamientos Conservadores del Órgano/métodos , Estudios Retrospectivos , Encuestas y Cuestionarios , Tasa de SupervivenciaRESUMEN
PURPOSE: Sphincter-preserving operations performed with bladder-preserving surgery and a cystourethral anastomosis (CUA) do not require a urinary stoma, but leakage from the CUA may develop. The aim of this study was to evaluate the efficacy of performing an additional flap operation. METHODS: The subjects were 39 patients who underwent bladder-preserving surgery for advanced rectal cancer involving the prostate, between 2001 and 2015.32 of whom had a CUA and one of whom had a neobladder. Five of these 32 patients underwent an ileal flap operation, 2 underwent an omental flap operation, and 3 underwent an operation using both flaps. RESULTS: Leakage developed in 3 (30%) of the 10 patients who underwent additional flap operations, but in 14 (60.9%) of the 23 patients who did not undergo a flap operation. The mean periods of catheterization for the patients who suffered leakage were 31 weeks (8-108 weeks) in those without a flap and 16 weeks (8-20 weeks) in those with a flap. Four (33.3%) of the 12 patients with leakage after surgery without a flap had a period of urinary catheterization >30 weeks, and 2 (16.7%) had leakage of CTCAE grade 3. There were no cases of leakage after flap surgery. CONCLUSION: An additional flap operation may decrease the risk of leakage from a CUA.
Asunto(s)
Anastomosis Quirúrgica/métodos , Fuga Anastomótica/prevención & control , Neoplasias Colorrectales/cirugía , Tratamientos Conservadores del Órgano/métodos , Complicaciones Posoperatorias/prevención & control , Prostatectomía/métodos , Colgajos Quirúrgicos , Uretra/cirugía , Vejiga Urinaria/cirugía , Adulto , Anciano , Humanos , Íleon/trasplante , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Riesgo , Factores de TiempoRESUMEN
BACKGROUND: Data regarding anastomotic leakage (AL) following intersphincteric resection (ISR) are lacking. We aimed to evaluate the effect of AL on anal function in a retrospective review of patients who developed AL following ISR. METHODS: We evaluated 341 consecutive patients who underwent ISR between 2000 and 2012. Patients were classified into three groups: anastomotic dehiscence (AD), major AL (Clavien-Dindo grade III+), or control (Asunto(s)
Canal Anal/cirugía
, Fuga Anastomótica/etiología
, Neoplasias del Recto/cirugía
, Adulto
, Anciano
, Anciano de 80 o más Años
, Canal Anal/fisiopatología
, Anastomosis Quirúrgica/efectos adversos
, Anastomosis Quirúrgica/métodos
, Fuga Anastomótica/fisiopatología
, Fuga Anastomótica/terapia
, Defecación/fisiología
, Femenino
, Estudios de Seguimiento
, Humanos
, Estimación de Kaplan-Meier
, Masculino
, Persona de Mediana Edad
, Complicaciones Posoperatorias
, Neoplasias del Recto/patología
, Estudios Retrospectivos
, Estomas Quirúrgicos
, Dehiscencia de la Herida Operatoria/etiología