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We report the direct observation of muon neutrino interactions with the SND@LHC detector at the Large Hadron Collider. A dataset of proton-proton collisions at sqrt[s]=13.6 TeV collected by SND@LHC in 2022 is used, corresponding to an integrated luminosity of 36.8 fb^{-1}. The search is based on information from the active electronic components of the SND@LHC detector, which covers the pseudorapidity region of 7.2<η<8.4, inaccessible to the other experiments at the collider. Muon neutrino candidates are identified through their charged-current interaction topology, with a track propagating through the entire length of the muon detector. After selection cuts, 8 ν_{µ} interaction candidate events remain with an estimated background of 0.086 events, yielding a significance of about 7 standard deviations for the observed ν_{µ} signal.
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Van der Waals heterostructures show many intriguing phenomena including ultrafast charge separation following strong excitonic absorption in the visible spectral range. However, despite the enormous potential for future applications in the field of optoelectronics, the underlying microscopic mechanism remains controversial. Here we use time- and angle-resolved photoemission spectroscopy combined with microscopic many-particle theory to reveal the relevant microscopic charge transfer channels in epitaxial WS_{2}/graphene heterostructures. We find that the timescale for efficient ultrafast charge separation in the material is determined by direct tunneling at those points in the Brillouin zone where WS_{2} and graphene bands cross, while the lifetime of the charge separated transient state is set by defect-assisted tunneling through localized sulphur vacancies. The subtle interplay of intrinsic and defect-related charge transfer channels revealed in the present work can be exploited for the design of highly efficient light harvesting and detecting devices.
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Current biomedical research is centered on the study of nanomaterials and their effects in biological environments. In particular, there is an increasing interest on TiO2 nanostructures for biomedical applications such as drug delivery or implant materials. In this framework, we present a Chemical Vapour Deposition process to synthesize titanium dioxide nanowires (NWs) on a commercially pure titanium substrate and we test the material In Vitro as a culture substrate for murine osteoblast-like MC3T3-E1 cells. A physical-morphological, structural and optical-characterization of the inorganic samples is performed by Electron Microscopy techniques and X-ray Diffraction, showing that a mat of crystalline rutile TiO2 NWs is obtained over the commercial substrate. In Vitro biological tests are performed by seeding MC3T3-E1 cells on the material and studying cell morphology, the cellmaterial interface and the osteoblast gene expression. These experiments show good cell adhesion to the nano-structured surface and a higher degree of early osteoblastic differentiation compared to control titanium surfaces, indicating that the present nano-structured material has good osteogenic potential for biomedical applications.
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Nanoestruturas , Nanofios , Animais , Camundongos , Osteoblastos , Propriedades de Superfície , Titânio/farmacologiaRESUMO
Worldwide, breast cancer is the most commonly diagnosed cancer in women. Surgical procedures are typically performed using general anaesthesia, often complemented by regional anaesthesia to manage postoperative pain. However, avoidance of general anaesthesia for breast surgery may be desirable for clinical reasons or patient choice. It is theorised that the use of regional anaesthesia and the avoidance of volatile anaesthetics and opioid analgesia may have beneficial effects on oncological outcomes, and there is some evidence to support this. While many patients successfully undergo awake breast surgery, a limited number of anaesthetists possess direct experience of this approach, despite familiarity with regional anaesthesia techniques. Undertaking regional anaesthesia for awake breast surgery requires patient cooperation and excellent staff teamwork. Here, we present a case of a patient who underwent awake bilateral mastectomy with reconstruction. This was carried out under two 'paravertebral-by-proxy' blocks: the thoracic erector spinae plane and inter-transverse plane blocks, with intravenous sedation.
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We present two cases of nulliparous women with no history of amenorrhea who were referred to our unit following finding of a hypervascularized solid adnexal mass. In both cases a malignant tumor of tubal origin was suspected at transvaginal sonography. However, following laparoscopy, histological examination revealed that the masses were the result of an undetected tubal ectopic pregnancy that had failed spontaneously, with massive vasodilatation of pelvic blood vessels surrounding the trophoblastic tissue. We recommend consideration of the potential diagnosis of a previously undetected, failed tubal ectopic pregnancy in fertile women presenting with an adnexal mass, even when there is no history of amenorrhea or a positive pregnancy test.
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Neoplasias das Tubas Uterinas/diagnóstico por imagem , Gravidez Tubária/diagnóstico por imagem , Adulto , Diagnóstico Diferencial , Erros de Diagnóstico , Feminino , Humanos , Achados Incidentais , Gravidez , Neoplasias Trofoblásticas/diagnóstico por imagem , Ultrassonografia , Neoplasias Uterinas/diagnóstico por imagemRESUMO
Strain engineering is an efficient tool to tune and tailor the electrical and optical properties of 2D materials. The built-in strain can be tuned during the synthesis process of a two-dimensional semiconductor, such as molybdenum disulfide, by employing different growth substrates with peculiar thermal properties. In this work, we demonstrate that the built-in strain of MoS2 monolayers, grown on a SiO2/Si substrate by liquid precursor chemical vapor deposition, is mainly dependent on the size of the monolayer. In fact, we identify a critical size equal to 20 µm, from which the built-in strain increases drastically. The built-in strain is the maximum for a 60 µm sized monolayer, leading to 1.2% tensile strain with a partial release of strain close to the monolayer triangular vertexes due to the formation of nanocracks. These findings also imply that the standard method for evaluation of the number of layers based on the Raman mode separation can become unreliable for highly strained monolayers with a lateral size above 20 µm.
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BACKGROUND: Data are limited regarding bone metastases from colorectal cancer (CRC). The objective of this study was to survey the natural history of bone metastasis in CRC. PATIENTS AND METHODS: This retrospective, multicenter, observational study of 264 patients with CRC involving bone examined cancer treatments, bone metastases characteristics, skeletal-related event (SRE) type and frequency, zoledronic acid therapy, and disease outcomes. RESULTS: Most patients with bone metastases had pathologic T3/4 disease at CRC diagnosis. The spine was the most common site involved (65%), followed by hip/pelvis (34%), long bones (26%), and other sites (17%). Median time from CRC diagnosis to bone metastases was 11.00 months; median time to first SRE thereafter was 2.00 months. Radiation and pathologic fractures affected 45% and 10% of patients, respectively; 32% of patients had no reported SREs. Patients survived for a median of 7.00 months after bone metastases diagnosis; SREs did not significantly affect survival. Subgroup analyses revealed that zoledronic acid significantly prolonged median time to first SRE (2.00 months versus 1.00 month, respectively, P=0.009) and produced a trend toward improved overall survival versus no zoledronic acid. CONCLUSION: This study illustrates the burden of bone metastases from CRC and supports the use of zoledronic acid in this setting.
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Neoplasias Ósseas/secundário , Neoplasias Colorretais/patologia , Conservadores da Densidade Óssea/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Difosfonatos/uso terapêutico , Humanos , Imidazóis/uso terapêutico , Estudos Retrospectivos , Ácido ZoledrônicoRESUMO
Evidence for the neutron-rich hypernucleus (Λ)(6)H is presented from the FINUDA experiment at DAΦNE, Frascati, studying (π+,π-) pairs in coincidence from the K(stop)(-) + (6)Li â(Λ)(6)H + π+ production reaction followed by (Λ)(6)H â (6)He + π- weak decay. The production rate of (Λ)(6) undergoing this two-body π- decay is determined to be (2.9 ± 2.0) × 10(-6)/K(stop)(-). Its binding energy, evaluated jointly from production and decay, is BΛ((Λ)(6)H) = (4.0 ± 1.1) MeV with respect to (5)H+Λ. A systematic difference of (0.98 ± 0.74) MeV between BΛ values derived separately from decay and from production is tentatively assigned to the (Λ)(6)H 0(g.s.)(+) â 1+ excitation.
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MoS2 micro-pyramids have demonstrated interesting properties in the fields of photonics and non-linear optics. In this work, we show the excitonic absorption and cathodoluminescence (CL) emission of MoS2 micro-pyramids grown by chemical vapor deposition (CVD) on SiO2 substrates. The excitonic absorption was obtained at room and cryogenic temperatures by taking advantage of the cathodoluminescence emission of the SiO2 substrate. We detected the CL emission related to defect intra-gap states, localized at the pyramid edges and with an enhanced intensity at the pyramid basal vertices. The photoluminescence and absorption analysis provided the Stokes shift of both the A and B excitons in the MoS2 pyramids. This analysis provides new insights into the optical functionality of MoS2 pyramids. This method can be applied to other 3D structures within the 2D materials family.
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The employment of two-dimensional materials, as growth substrates or buffer layers, enables the epitaxial growth of layered materials with different crystalline symmetries with a preferential crystalline orientation and the synthesis of heterostructures with a large lattice constant mismatch. In this work, we employ single crystalline graphene to modify the sulfurization dynamics of copper foil for the deterministic synthesis of large-area Cu9S5 crystals. Molecular dynamics simulations using the Reax force-field are used to mimic the sulfurization process of a series of different atomistic systems specifically built to understand the role of graphene during the sulphur atom attack over the Cu(111) surface. Cu9S5 flakes show a flat morphology with an average lateral size of hundreds of micrometers. Cu9S5 presents a direct band-gap of 2.5 eV evaluated with light absorption and light emission spectroscopies. Electrical characterization shows that the Cu9S5 crystals present high p-type doping with a hole mobility of 2 cm2 V-1 s-1.
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The use of metal nanoparticles is an established paradigm for the synthesis of semiconducting one-dimensional nanostructures. In this work we study their effect on the synthesis of two-dimensional semiconducting materials, by using gold nanoparticles for chemical vapor deposition growth of two-dimensional molybdenum disulfide (MoS2). In comparison with the standard method, the employment of gold nanoparticles allows us to obtain large monolayer MoS2 flakes, up to 20 µm in lateral size, even if they are affected by the localized overgrowth of MoS2 bilayer and trilayer islands. Important modifications of the optical and electronic properties of MoS2 triangular domains are reported, where the photoluminescence intensity of the A exciton is strongly quenched and a shift to a positive threshold voltage in back-gated field effect transistors is observed. These results indicate that the use of gold nanoparticles influences the flake growth and properties, indicating a method for possible localized synthesis of two-dimensional materials, improving the lateral size of monolayers and modifying their properties.
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Chemical vapor deposition has been demonstrated to be the most efficient, versatile and reliable technique for the synthesis of monolayers of transition metal dichalcogenides. The use of organic promoters during the growth process was a turning point in order to increase the monolayer lateral size or to obtain complete coverage of the growth substrate. In this work we clarify the influence of the promoter gradient on the growth dynamics of MoS2. In particular, we place a sacrificial substrate covered with a promoter (a low sublimation-temperature perylene-based compound) downstream with respect to the growth substrate in order to maximize its gradient on the growth substrate through upstream diffusion. We demonstrate that the morphology and the number of layers of MoS2 are drastically affected by the distance of the growth substrate from the promoter sacrificial substrate. The farthermost area from the promoter substrate presents micrometric MoS2 triangular monolayers and large low hierarchy dendritic multi-layer structures. On the contrary the closest area reveals an almost continuous polycrystalline MoS2 monolayer, with bilayer terraces, with a lateral dimension up to hundreds of micrometers.
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Highly oriented pyrolytic graphite (HOPG) is an inert substrate with a structural honeycomb lattice, well suited for the growth of a two-dimensional (2D) silicene layer. It was reported that when Si atoms are deposited on the HOPG surface at room temperature, they arrange into two configurations: silicene nanosheets and three-dimensional clusters. In this work we demonstrate, by using scanning tunneling microscopy (STM) and Raman spectroscopy, that a third configuration stabilizes in the form of Si 2D nanosheets intercalated below the first top layer of carbon atoms. The Raman spectra reveal a structure located at 538 cm-1 which we ascribe to the presence of sp2 Si hybridization. Moreover, the silicon deposition induces several modifications in the graphite D and G Raman modes, which we interpret as experimental evidence of the intercalation of the silicene nanosheets. The Si atom intercalation at room temperature takes place at the HOPG step edges and it detaches only the outermost graphite layer inducing a strong tensile strain mainly concentrated on the edges of the silicene nanosheets. Theoretical calculations of the structure and energetic viability of the silicene nanosheets and of the strain distribution on the outermost graphite layer and its influence on the Raman resonances support the STM and Raman observations.
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BACKGROUND: The p53 codon 72 polymorphism, which results in either an arginine or proline residue, plays a different role in vitro and in vivo in cell survival and drug resistance. We verified, in vitro, the impact of the arginine allele on cell survival under normoxia and hypoxia, and investigated in vivo the role of p53 codon 72 arginine homozygosity in the clinical outcome of advanced breast cancer patients. METHODS: Tumors at advanced stages grow in vivo in a hypoxic environment, and we mimicked such conditions in vitro using p53 null breast cancer cells transfected with either the arginine or proline allele. We also analyzed in vivo the p53 codon 72 genotype status of advanced breast cancer patients. RESULTS: In vitro transfection of the arginine allele induced higher cell death under normoxia, whereas cell death was greater in proline-transfected cells under hypoxia. The arginine allele upregulated BCRP-I, a hypoxia response gene, which increases drug resistance. Metastatic breast cancer patients homozygous for arginine had a significantly shorter time to progression and overall survival than those with heterozygous arginine/proline tumors. CONCLUSION: We provide a molecular explanation for the association of the arginine allele with tumor aggressiveness and treatment resistance in advanced breast cancer.
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Alelos , Arginina/genética , Neoplasias da Mama/genética , Códon/genética , Polimorfismo de Nucleotídeo Único/genética , Proteína Supressora de Tumor p53/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Adulto , Idoso , Neoplasias da Mama/patologia , Neoplasias da Mama/fisiopatologia , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Hipóxia/fisiopatologia , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Prolina/genética , Transfecção , Regulação para CimaRESUMO
Studies on cyclopentenone prostaglandins (CPPGs), clavulones and other cyclopentenones have shown that these compounds have a significant anticancer activity mediated by their cyclopentenone (CP) chemical moiety. In this study the cytotoxicity against cancer cells of the model compound cyclopent-2-en-1-one (2CP) was investigated. Being a highly water soluble small molecule, 2CP could be an ideal candidate to overcome pharmacological issues related to drug delivery and penetration. Its cytotoxic activity was tested on various melanoma and lung cancer cells. Interestingly, 2CP was both cytotoxic and pro-apoptotic, more pronounced on melanoma cells, at concentrations in the sub-micromolar range. On melanoma cells its mechanism of action was mediated by the mitochondria and the activation of caspase 3.
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Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Ciclopentanos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Melanoma/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Neoplasias Pulmonares/patologia , Melanoma/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacosRESUMO
One of the major issues in graphene-based optoelectronics is to scale-up high-performing devices. In this work, we report an original approach for the fabrication of efficient optoelectronic devices from scalable tungsten disulfide (WS2)/graphene heterostructures. Our approach allows for the patterned growth of WS2 on graphene and facilitates the realization of ohmic contacts. Photodetectors fabricated with WS2 on epitaxial graphene on silicon carbide (SiC) present, when illuminated with red light, a maximum responsivity R â¼220 A W-1, a detectivity D* â¼2.0 × 109 Jones and a -3 dB bandwidth of 250 Hz. The retrieved detectivity is 3 orders of magnitude higher than that obtained with graphene-only devices at the same wavelength. For shorter illumination wavelengths we observe a persistent photocurrent with a nearly complete charge retention, which originates from deep trap levels in the SiC substrate. This work ultimately demonstrates that WS2/graphene optoelectronic devices with promising performances can be obtained in a scalable manner. Furthermore, by combining wavelength-selective memory, enhanced responsivity and fast detection, this system is of interest for the implementation of 2d-based data storage devices.
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OBJECTIVE: Taxanes and fluoropyrimidines are active in metastatic breast cancer (MBC), and their combination has proven effective in anthracycline-refractory patients. We conducted a phase I study to determine the maximum tolerated dose (MTD) of uracil plus tegafur (UFT) given in combination with leucovorin (LV) and paclitaxel (Pacl) in patients with refractory MBC. METHODS: Pacl was infused at a fixed dose of 150 mg/m2 on day 1. UFT, at doses escalated by 50 mg/m2 starting from 200 mg/m2 . day, and LV, at a fixed dose of 90 mg/day, were given orally every 8 h for 11 days (days 3-13). Cohorts of at least 3 patients were treated at each dose level, and if 1 experienced dose-limiting toxicity (DLT), a maximum of 3 additional patients were added at the same dose level. MTD was reached if 2 out of the 6 patients experienced DLT. RESULTS: Sixteen patients were enrolled in the study. The most important toxicity observed was hematological. Nonhematological toxicities were paresthesia and myalgia, asthenia, nausea, and mucositis. DLT occurred in only 1 patient (grade 3 hepatic toxicity). CONCLUSIONS: The recommended dose for a subsequent phase II trial is Pacl 150 mg/m2 on day 1, and UFT 300 mg/m2 and LV 90 mg on days 3-13, every 2 weeks.
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Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Esquema de Medicação , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Leucovorina/administração & dosagem , Dose Máxima Tolerável , Pessoa de Meia-Idade , Modelos Teóricos , Metástase Neoplásica , Paclitaxel/administração & dosagem , Tegafur/administração & dosagem , Uracila/administração & dosagemRESUMO
BACKGROUND: Whereas the efficacy of statins after heart transplantation (HT) in controlled study settings has been clearly demonstrated, more extensive data are required on the safety and effectiveness of long-term treatment in routine clinical practice. METHODS: We analyzed the risks and benefits in clinical practice of treatment with statins in all patients who survived HT for at least a month from December 1985 through 2001. RESULTS: During a mean follow-up of 4.8+/-3.8 years, 186 patients were treated with statins (for a median duration [25th to 75th percentile] of 29 [12 to 54] months), while 48 received dietary therapy alone. Patients treated with statins (pravastatin, 48%; atorvastatin, 37%; simvastatin, 14%) presented linearized rates of rhabdomyolisis, myositis, and significant transaminase elevation of 0.37%, 0.74%, and 0.37% per year of treatment, respectively (no fatal event occurred). Low-density lipoprotein decreased after statins by 19% (P<.001). At multivariate analysis, treatment with statins was independently associated with reduced risk of cardiac allograft vasculopathy and overall mortality (P<.001). CONCLUSIONS: Our data provide necessary confirmation of the safety and effectiveness in routine clinical practice of appropriately monitored long-term administration of statins (particularly atorvastatin, pravastatin, and simvastatin) in the chronic post-HT phase. Strict follow-up is needed for HT recipients receiving high doses of statins with/without other medications potentially exacerbating the risk of adverse effects.
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Transplante de Coração/fisiologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Adulto , Feminino , Cardiopatias/classificação , Cardiopatias/cirurgia , Transplante de Coração/mortalidade , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Segurança , Análise de Sobrevida , Sobreviventes , Resultado do TratamentoRESUMO
The structural defects in two-dimensional transition metal dichalcogenides, including point defects, dislocations and grain boundaries, are scarcely considered regarding their potential to manipulate the electrical and optical properties of this class of materials, notwithstanding the significant advances already made. Indeed, impurities and vacancies may influence the exciton population, create disorder-induced localization, as well as modify the electrical behaviour of the material. Here we report on the experimental evidence, confirmed by ab initio calculations, that sulfur vacancies give rise to a novel near-infrared emission peak around 0.75 eV in exfoliated MoS2 flakes. In addition, we demonstrate an excess of sulfur vacancies at the flake's edges by means of cathodoluminescence mapping, aberration-corrected transmission electron microscopy imaging and electron energy loss analyses. Moreover, we show that ripplocations, extended line defects peculiar to this material, broaden and redshift the MoS2 indirect bandgap emission.