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Oral squamous cell carcinoma (OSCC) is a complex disease with a high potential for lymph node metastasis and poor survival rates. Accurate nodal staging is crucial for prognostic assessment and treatment planning in OSCC. Recent research has suggested that nodal tumor volume (NTV) may be a more accurate indicator of nodal disease burden than traditional staging methods. However, the prognostic significance of NTV in OSCC remains unclear. This systematic review aims to evaluate the existing evidence on the relationship between NTV and prognosis in OSCC. A comprehensive search of electronic databases was conducted, and studies meeting inclusion criteria were critically appraised and synthesized. Our review identified 23 studies that investigated the prognostic significance of NTV in OSCC. The majority of studies reported that larger NTV was associated with poorer survival outcomes, although the strength of the association varied. The review also identified several areas for future research, including the standardization of NTV measurement and the integration of NTV into the broader landscape of OSCC management. In conclusion, our review suggests that NTV holds promise as a novel prognostic factor in OSCC, but more research is needed to fully elucidate its potential and inform clinical decision-making.
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Through the coupling of central and terminal naphthalene diimide functionalities, a unique non-fullerene electron acceptor, coded as N10, was designed, synthesized, characterized and applied in solution-processable bulk-heterojunction devices. The target N10 displayed good solubility, excellent thermal stability and energy levels complementing those of the conventional donor polymer poly(3-hexyl thiophene) (P3HT). An excellent power conversion efficiency of 7.65% was obtained in simple BHJ devices (P3HT : N10 1 : 1.2), which is the highest observed so far for NDI core-based non-fullerene acceptors.
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Computational screening is key to understanding structure-function relationships at the nanoscale but the high computational cost of accurate electronic structure calculations remains a bottleneck for the screening of large nanomaterial libraries. In this work we propose a data-driven strategy to predict accuracy differences between different levels of theory. Machine learning (ML) models are trained with structural features of graphene nanoflakes to predict the differences between electronic properties at two levels of approximation. The ML models yield an overall accuracy of 94% and 88%, for energy of the Fermi level and the band gap, respectively. This strategy represents a successful application of established ML methods to the selection of optimum level of theory, enabling more rapid and efficient screening of nanomaterials, and is extensible to other materials and computational methods.
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BACKGROUND: We assessed the treatment effect of panitumumab plus best supportive care (BSC) vs BSC on overall survival (OS) in patients with chemorefractory wild-type KRAS exon 2 metastatic colorectal cancer (mCRC) and report the first prospective extended RAS analysis in a phase 3 trial. METHODS: Patients with wild-type KRAS exon 2 mCRC were randomised 1 : 1 to panitumumab (6 mg kg-1 Q2W) plus BSC or BSC. On-study crossover was prohibited. RAS mutation status was determined by central laboratory testing. The primary endpoint was OS in wild-type KRAS exon 2 mCRC; OS in wild-type RAS mCRC (KRAS and NRAS exons 2, 3, and 4) was a secondary endpoint. RESULTS: Three hundred seventy seven patients with wild-type KRAS exon 2 mCRC were randomised. Median OS was 10.0 months with panitumumab plus BSC vs 7.4 months with BSC (HR=0.73; 95% CI=0.57-0.93; P=0.0096). RAS ascertainment was 86%. In wild-type RAS mCRC, median OS for panitumumab plus BSC was 10.0 vs 6.9 months for BSC (HR=0.70; 95% CI=0.53-0.93; P=0.0135). Patients with RAS mutations did not benefit from panitumumab (OS HR=0.99; 95% CI=0.49-2.00). No new safety signals were observed. CONCLUSIONS: Panitumumab significantly improved OS in wild-type KRAS exon 2 mCRC. The effect was more pronounced in wild-type RAS mCRC, validating previous retrospective analyses.
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Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas ras/genética , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/genética , Terapia Combinada/métodos , Estudios Cruzados , Exones/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación/genética , Panitumumab , Estudios Prospectivos , Adulto JovenRESUMEN
Pure graphene is known as the strongest material ever discovered. However, the unavoidable defect formation in the fabrication process renders the strength of defective graphene much lower (~14%) than that of its perfect counterpart. By means of density functional theory computations, we systematically explored the effect of gas molecules (H2, N2, NH3, CO, CO2 and O2) adsorption on the mechanical strength of perfect/defective graphene. The NH3 molecule is found to play a dominant role in enhancing the strength of defective graphene by up to ~15.6%, while other gas molecules decrease the strength of graphene with varying degrees. The remarkable strength enhancement can be interpreted by the decomposition of NH3, which saturates the dangling bond and leads to charge redistribution at the defect site. The present work provides basic information for the mechanical failure of gas-adsorbed graphene and guidance for manufacturing graphene-based electromechanical devices.
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By first-principle calculations, we have systematically studied the effect of strain/pressure on the electronic structure of rutile lead/stannic dioxide (PbO2/SnO2). We find that pressure/strain has a significant impact on the electronic structure of PbO2/SnO2. Not only can the band gap be substantially tuned by pressure/strain, but also a transition between a semiconductor and a gapless/band-inverted semimetal can be manipulated. Furthermore, the semimetallic state is robust under strain, indicating a bright perspective for electronics applications. In addition, a practical approach to realizing strain in SnO2 is then proposed by substituting tin (Sn) with lead (Pb), which also can trigger the transition from a large-band-gap to a moderate-gap semiconductor with enhanced electron mobility. This work is expected to provide guidance for full utilization of the flexible electronic properties in PbO2 and SnO2.
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Two-dimensional (2D) boron sheets have been successfully synthesized in recent experiments, however, some important issues remain, including the dynamical instability, high energy, and the active surface of the sheets. In an attempt to stabilize 2D boron layers, we have used density functional theory and global minimum search with the particle-swarm optimization method to predict four stable 2D boron hydride layers, namely the C2/m, Pbcm, Cmmm, and Pmmn sheets. The vibrational normal mode calculations reveal all these structures are dynamically stable, indicating potential for successful experimental synthesis. The calculated Young's modulus indicates a high mechanical strength for the C2/m and Pbcm phases. Most importantly, the C2/m, Pbcm, and Pmmn structures exhibit Dirac cones with massless Dirac fermions and the Fermi velocities for the Pbcm and Cmmm structures are even higher than that of graphene. The Cmmm phase is reported as the first discovery of Dirac ring material among boron-based 2D structures. The unique electronic structure of the 2D boron hydride sheets makes them ideal for nanoelectronics applications.
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Through the conjunction of tetraphenylethylene and diketopyrrolopyrrole functionalities, a novel four-directional non-fullerene electron acceptor (denoted as 4D) was designed, synthesized and characterized. The new chromophore is highly soluble (for instance >30 mg mL(-1) in o-dichlorobenzene), thermally stable, and exhibits energy levels matching those of the conventional and routinely used donor polymer poly(3-hexyl thiophene). A power conversion efficiency of 3.86% was obtained in solution-processable bulk-heterojunction devices with a very high open circuit voltage of 1.18 V.
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Recently, partially ionic boron (γ-B28) has been predicted and observed in pure boron, in bulk phase and controlled by pressure [ Nature 2009 , 457 , 863 ]. By using ab initio evolutionary structure search, we report the prediction of ionic boron at a reduced dimension and ambient pressure, namely, the two-dimensional (2D) ionic boron. This 2D boron structure consists of graphene-like plane and B2 atom pairs with the P6/mmm space group and six atoms in the unit cell and has lower energy than the previously reported α-sheet structure and its analogues. Its dynamical and thermal stability are confirmed by the phonon-spectrum and ab initio molecular dynamics simulation. In addition, this phase exhibits double Dirac cones with massless Dirac Fermions due to the significant charge transfer between the graphene-like plane and B2 pair that enhances the energetic stability of the P6/mmm boron. A Fermi velocity (vf) as high as 2.3 × 10(6) m/s, which is even higher than that of graphene (0.82 × 10(6) m/s), is predicted for the P6/mmm boron. The present work is the first report of the 2D ionic boron at atmospheric pressure. The unique electronic structure renders the 2D ionic boron a promising 2D material for applications in nanoelectronics.
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Aim of the research is to establish the prevalence of dyspepsia in Osjecko-baranjska County, to establish its specific characteristics and to determine the effect of demographic, anthropometric, and socioeconomic factors. It is a cross-sectional and case control study conducted in 2010 on systematic sample of 900 subjects between 20 and 69 years of age. Every subject was sent an invitation letter and a Rome III diagnostic questionnaire for one of the disorders. A scoring algorithm was used to confirm or exclude the diagnosis of functional dyspepsia (FD). The chi-square test, t-test and logistic regression were used for analysis.Prevalence of dyspepsia was recorded in 16, 56%, of subjects. There is no statistically significant difference in prevalence of dyspepsia male and female. The prevalence of dyspepsia increases with age. Correlation with the place of birth was proven. There is no correlation between the current place of residence (rural area and town) and dyspepsia. There is a correlation with marital status. Correlation between stool forms was proven. There were a greater number of subjects that had at least one alarm symptom or some of the psychosocial factors and they often suffered from a chronic disease. The risk for dyspepsia increases with age, body mass index (BMI), and poorer health. Logistic regression showed the following as statistically significant for dyspepsia: place of birth and self-assessment of one's health. FD presents a significant health problem. Rome III survey questionnaire proved to be an acceptable method for diagnosing this functional disorder in clinical-consilliary and primary health care for persons showing signs of alarm and needing further diagnostic treatment.
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Depresión/epidemiología , Dispepsia/epidemiología , Enfermedades Gastrointestinales/epidemiología , Trastornos Mentales/epidemiología , Enfermedades Musculoesqueléticas/epidemiología , Trastornos Respiratorios/epidemiología , Adulto , Distribución por Edad , Anciano , Tamaño Corporal , Comorbilidad , Croacia/epidemiología , Depresión/psicología , Dispepsia/psicología , Femenino , Enfermedades Gastrointestinales/psicología , Vivienda/estadística & datos numéricos , Humanos , Masculino , Trastornos Mentales/psicología , Persona de Mediana Edad , Enfermedades Musculoesqueléticas/psicología , Prevalencia , Psicología , Trastornos Respiratorios/psicología , Factores de Riesgo , Distribución por Sexo , Factores Socioeconómicos , Adulto JovenRESUMEN
Single layered transition metal dichalcogenides have attracted tremendous research interest due to their structural phase diversities. By using a global optimization approach, we have discovered a new phase of transition metal dichalcogenides (labelled as T''), which is confirmed to be energetically, dynamically and kinetically stable by our first-principles calculations. The new T'' MoS2 phase exhibits an intrinsic quantum spin Hall (QSH) effect with a nontrivial gap as large as 0.42 eV, suggesting that a two-dimensional (2D) topological insulator can be achieved at room temperature. Most interestingly, there is a topological phase transition simply driven by a small tensile strain of up to 2%. Furthermore, all the known MX2 (M = Mo or W; X = S, Se or Te) monolayers in the new T'' phase unambiguously display similar band topologies and strain controlled topological phase transitions. Our findings greatly enrich the 2D families of transition metal dichalcogenides and offer a feasible way to control the electronic states of 2D topological insulators for the fabrication of high-speed spintronics devices.
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Layered graphitic materials exhibit new intriguing electronic structure and the search for new types of two-dimensional (2D) monolayer is of importance for the fabrication of next generation miniature electronic and optoelectronic devices. By means of density functional theory (DFT) computations, we investigated in detail the structural, electronic, mechanical and optical properties of the single-layer bismuth iodide (BiI3) nanosheet. Monolayer BiI3 is dynamically stable as confirmed by the computed phonon spectrum. The cleavage energy (Ecl) and interlayer coupling strength of bulk BiI3 are comparable to the experimental values of graphite, which indicates that the exfoliation of BiI3 is highly feasible. The obtained stress-strain curve shows that the BiI3 nanosheet is a brittle material with a breaking strain of 13%. The BiI3 monolayer has an indirect band gap of 1.57 eV with spin orbit coupling (SOC), indicating its potential application for solar cells. Furthermore, the band gap of BiI3 monolayer can be modulated by biaxial strain. Most interestingly, interfacing electrically active graphene with monolayer BiI3 nanosheet leads to enhanced light absorption compared to that in pure monolayer BiI3 nanosheet, highlighting its great potential applications in photonics and photovoltaic solar cells.
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Through the incorporation of a thiophene functionality, a novel solution-processable small organic chromophore was designed, synthesized and characterized for application in bulk-heterojunction solar cells. The new chromophore, (2Z,2'Z)-2,2'-(1,4-phenylene)bis(3-(5-(4-(diphenylamino)phenyl)thiophen-2-yl)acrylonitrile) (coded as AS2), was based on a donor-acceptor-donor (D-A-D) module where a simple triphenylamine unit served as an electron donor, 1,4-phenylenediacetonitrile as an electron acceptor, and a thiophene ring as the π-bridge embedded between the donor and acceptor functionalities. AS2 was isolated as brick-red, needle-shaped crystals, and was fully characterized by ¹H- and (13)C-NMR, IR, mass spectrometry and single crystal X-ray diffraction. The optoelectronic and photovoltaic properties of AS2 were compared with those of a structural analogue, (2Z,2'Z)-2,2'-(1,4-phenylene)bis(3-(4-(diphenylamino)phenyl)-acrylonitrile) (AS1). Benefiting from the covalent thiophene bridges, compared to AS1 thin solid film, the AS2 film showed: (1) an enhancement of light-harvesting ability by 20%; (2) an increase in wavelength of the longest wavelength absorption maximum (497 nm vs. 470 nm) and (3) a narrower optical band-gap (1.93 eV vs. 2.17 eV). Studies on the photovoltaic properties revealed that the best AS2-[6,6]-phenyl-C61-butyric acid methyl ester (PC61BM)-based device showed an impressive enhanced power conversion efficiency of 4.10%, an approx. 3-fold increase with respect to the efficiency of the best AS1-based device (1.23%). These results clearly indicated that embodiment of thiophene functionality extended the molecular conjugation, thus enhancing the light-harvesting ability and short-circuit current density, while further improving the bulk-heterojunction device performance. To our knowledge, AS2 is the first example in the literature where a thiophene unit has been used in conjunction with a 1,4-phenylenediacetonitrile accepting functionality to extend the π-conjugation in a given D-A-D motif for bulk-heterojunction solar cell applications.
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Colorantes/química , Tiofenos/química , Cristalografía por Rayos X , Electroquímica , Procesos Fotoquímicos , Energía Solar , SolucionesRESUMEN
Two solution-processable small organic molecules, (E)-6,6'-bis(4-(diphenylamino)phenyl)-1,1'-bis(2-ethylhexyl)-(3,3'-biindolinylidene)-2,2'-dione (coded as S10) and (E)-6,6'-di(9H-carbazol-9-yl)-1,1'-bis(2-ethylhexyl)-(3,3'-biindolinylidene)-2,2'-dione (coded as S11) were successfully designed, synthesized and fully characterized. S10 and S11 are based on a donor-acceptor-donor structural motif and contain a common electron accepting moiety, isoindigo, along with different electron donating functionalities, triphenylamine and carbazole, respectively. Ultraviolet-visible absorption spectra revealed that the use of triphenylamine donor functionality resulted in an enhanced intramolecular charge transfer transition and reduction of optical band gap, when compared with its carbazole analogue. Both of these materials were designed to be donor semiconducting components, exerted excellent solubility in common organic solvents, showed excellent thermal stability, and their promising optoelectronic properties encouraged us to scrutinize charge-carrier mobilities using solution-processable organic field effect transistors. Hole mobilities of the order of 2.2 × 10(-4) cm²/Vs and 7.8 × 10(-3) cm²/Vs were measured using S10 and S11 as active materials, respectively.
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Indoles/química , Indoles/síntesis química , Aminas/química , Carbazoles/química , Estructura Molecular , SemiconductoresRESUMEN
By designing dyes with fluoroalkyl groups, the optical and electronic properties of the alkyl analogue were maintained while dramatically altering the solubility. Dyes, F-TABTA (8) and its masked derivative F-TABTSi (9), that enable them to be deposited under conventional organic solvent and scCO2 conditions, respectively, were developed. In liquid DSSC devices, the fluoroalkyl dye (F-TABTA, 8) performs slightly better than its alkyl analogue (D21L6, 10), and interestingly, it was found that the former device showed better stability over time. Deploying the silyl-masked precursor F-TABTSi (9), this dye was deposited onto TiO2 photoanodes from scCO2 in very short contact times (2.5 h), and ECEs of 7.70% were obtained that exceed the performance of the alkyl dye when deposited by conventional methods.
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We report a case of a 42-year-old man with a rare disorder known as primary intestinal lymphangiectasia, which is characterized by dilated intestinal lymphatics that lead to the development of protein-losing enteropathy. The patient presented with a grand mal seizure caused by malabsorption-derived electrolytes and a protein disorder. Signs of the disease, including chronic diarrhea and peripheral edema, manifested 10 years ago, but a diagnosis was never made. The diagnosis was suspected because of the clinical manifestations, laboratory tests, imaging and endoscopic findings. Hyperemic and edematous mucosa of the small intestine corresponded to scattered white spots with dilated intestinal lymphatics and whitish villi in the histological specimen of the biopsied jejunal mucosa. Although numerous therapeutic strategies are available, only octreotide therapy proved to be an effective means of therapeutic resolution in this patient. Although the patient had a partial remission following the use of a slow release formula of octreotide, his prognosis, clinical course, and future treatment challenges are yet to be determined.
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Fármacos Gastrointestinales/uso terapéutico , Intestinos/efectos de los fármacos , Linfangiectasia Intestinal/tratamiento farmacológico , Linfedema/tratamiento farmacológico , Octreótido/uso terapéutico , Adulto , Biopsia , Enteroscopía de Doble Balón , Epilepsia Tónico-Clónica/etiología , Humanos , Intestinos/diagnóstico por imagen , Intestinos/patología , Linfangiectasia Intestinal/complicaciones , Linfangiectasia Intestinal/diagnóstico , Linfedema/complicaciones , Linfedema/diagnóstico , Masculino , Valor Predictivo de las Pruebas , Cintigrafía , Radiofármacos , Agregado de Albúmina Marcado con Tecnecio Tc 99m , Resultado del TratamientoRESUMEN
Using the evolutionary optimization algorithm, as implemented in the USPEX crystal predictor program, and first principles total energy calculations, the compositional phase diagrams for Al-Sc and Al-Ta alloy systems at zero temperature and pressure have been calculated. In addition to the known binary intermetallic phases, new potentially stable alloys, AlSc3 and AlTa7, have been identified in the Al-poor region of the phase diagram. The dynamic and thermal stability of their lattices has been confirmed from the calculated vibrational normal mode spectra in the harmonic approximation.
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A novel solution-processable non-fullerene electron acceptor 6,6'-(5,5'-(9,9-dioctyl-9H-fluorene-2,7-diyl)bis(thiophene-5,2-diyl))bis(2,5-bis(2-ethylhexyl)-3-(thiophen-2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione) (DPP1) based on fluorene and diketopyrrolopyrrole conjugated moieties was designed, synthesized and fully characterized. DPP1 exhibited excellent solubility and high thermal stability which are essential for easy processing. Upon using DPP1 as an acceptor with the classical electron donor poly(3-hexylthiophene), solution processable bulk-heterojunction solar cells afforded a power conversion efficiency of 1.2% with a high open-circuit voltage (1.1 V). As per our knowledge, this value of open circuit voltage is one of the highest values reported so far for a bulk-heterojunction device using DPP1 as a non-fullerene acceptor.
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Fluorenos/química , Pirroles/química , Energía Solar , Tiofenos/síntesis química , Suministros de Energía Eléctrica , Electrones , Pirroles/síntesis química , Teoría Cuántica , Espectrofotometría Ultravioleta , Tiofenos/químicaRESUMEN
INTRODUCTION: Portal vein in healthy subjects and in patient with chronic diffuse liver disease was investigated by the combination of real-time technique and Doppler impulsive system. PATIENTS AND METHODS: Control group consisted of 99 healthy subjects of median age of 36,8, and with life raging span from 14 to 77 yrs. Experimental group consisted of 55 patients with histologically proved liver disease approximately aged 48,1 yrs. And with life span from 11 to 77 yrs. In 15 patients, portal hypertension was proved, by the measurement of Wedged hepatic venous pressure (WXVP). RESULTS: VP diameter was normally distributed in healthy subjects, variable with E(X) = 11,202 mm and SD = 1, 2534. The mentioned variable was also normally distributed in experimental group with E(X) = 10, 8 mm and SD = 1, 4832. VP diameter in healthy subjects did not statistically significantly differ from that one of the patient with chronic diffuse liver disease, which in contradictory to the generally accepted concepts. According to our results, portal vein diameter should not be taken as a parameter of portal hypertension.
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Hepatopatías/fisiopatología , Vena Porta/diagnóstico por imagen , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Niño , Enfermedad Crónica , Femenino , Humanos , Circulación Hepática/fisiología , Masculino , Persona de Mediana Edad , Ultrasonografía Doppler , Adulto JovenRESUMEN
Aim of the research is to establish the prevalence of constipation in Osjecko-baranjska County, to establish its specific characteristics and to determine the effect of demographic, anthropometric and socioeconomic factors. It is a cross-sectional study conducted in 2010. on systematic sample of 900 subjects between 20 and 69 years of age. Every subject was sent an invitation letter and a Rome III diagnostic questionnaire for one of the disorders. A scoring algorithm was used to confirm or exclude the diagnosis of functional constipation. The chi-square test (chi2 test), t-test and logistic regression were used for analysis. The prevalence of constipation in our study was 22.19%, which is higher than the prevalence in most other countries, where it ranges from 5% to 18%. In our study statistically significant variables were: place of current residence (urban), education level (high school), marital status (divorced people), a larger number of household members and a lower health status by self-assessment. According to t-test persons with constipation on average are older, have higher average BMI and lower average grade valued financial status of households and their health. There were a greater number of subjects that had at least one alarm symptom or some of the psychosocial factors and they often suffered from a chronic disease. Functional constipation presents a significant health problem. Rome III survey questionnaire proved to be an acceptable method for diagnosing this functional disorder in clinical-consilliary and primary health care, and for persons showing signs of alarm and needing further diagnostic treatment.