Up to 300†K lasing with GeSn-On-Insulator microdisk resonators.

GeSn alloys are the most promising direct band gap semiconductors to demonstrate full CMOS-compatible laser integration with a manufacturing from Group-IV materials. Here, we show that room temperature lasing, up to 300 K, can be obtained with GeSn. This is achieved in microdisk resonators fabricated on a GeSn-On-Insulator platform by combining strain engineering with a thick layer of high Sn content GeSn.

Assessment of self-efficacy for caregiving in oncology: Italian validation of the caregiver inventory (CGI-I).

BACKGROUND: The Caregiver Inventory (CGI), a measure of self-efficacy for caregiving that takes into account aspects of caregiving that are neglected by current measures of caregiving, was translated into Italian and validated. METHODS: Ninety-one caregivers from a variety of locations in Italy completed the CGI-Italian (CGI-I) as well as the Hospital Anxiety and Depression Scale (HADS) and the Family Strain Questionnaire - Short Form (FSQ-SF). RESULTS: A confirmatory factor analysis based on the original CGI factor structure resulted in an adequate fit of the CGI-I using standard fit indices. Thus, the original factor structure was validated in the CGI-I: Managing Medical Information (α = 0.87), Caring for Care Recipient (α = 0.68), Caring for Oneself (α = 0.78), and Managing Difficult Interactions/Emotions (α = 0.55). The CGI-I total score was inversely related to anxiety (HADS, r = - 0.35, p = <.05), and depression (HADS, r = - 0.45, p = <.05). In addition, the CGI-I was inversely related to caregiver stress (FSQ-SF, r = - 0.39, p = <.05). Care of Oneself and Managing Difficult Interactions/Emotions emerged as the strongest and most robust negative relationships with anxiety, depression, and caregiver stress, which replicated, with similar constructs, findings from the original CGI. CONCLUSIONS: The results of this study established the CGI-I as a reliable and valid measure of self-efficacy for caregiving. This study also confirms the importance of self-care and managing difficult communication in the process of successfully navigating the demands of caregiving and in constructing interventions for caregivers who need support.

Uniform phosphorus doping of untapered germanium nanowires.

One of the major challenges in the growth of vapor-liquid-solid (VLS) nanowires is the control of dopant incorporation in the structures. In this work, we study the n-type doping and morphology of nanowires grown by chemical vapor deposition when HCl is introduced. We obtain fully untapered nanowires with a growth temperature up to 410 °C and measure their resistivity using the 4-probe technique to be 2.0 mΩ cm. We perform energy dispersive x-ray measurements showing a concentration of dopants in the (5-7) × 1018 cm-3 range, being radially and axially uniform. The combination of these two measurements shows that the mobility is the same as for bulk germanium, demonstrating that the VLS mechanism has no detrimental effect for the electron transport in these nanowires.

Adverse events risk associated with bevacizumab addition to breast cancer chemotherapy: a meta-analysis.

BACKGROUND: Bevacizumab is a monoclonal antibody against vascular endothelial growth factor with the ability to increase progression-free survival in metastatic breast cancer (MBC). A systematic review and meta-analysis was conducted to determine the risk of the most clinically relevant adverse outcomes associated with the use of bevacizumab in the treatment of breast cancer. PATIENTS AND METHODS: We included phase III clinical trials that used bevacizumab alone or in combination with chemotherapy as for MBC or locally recurrent. Statistical analyses were conducted to calculate summary odds ratio (OR) of the eight most relevant adverse outcomes related with bevacizumab. RESULTS: Five clinical trials were included in the meta-analysis. Summary odds ratios obtained showed a statistically significant bevacizumab-associated increased risk in four of the adverse outcomes studied: proteinuria (OR = 27.68), hypertension (OR = 12.76), left ventricular dysfunction (LVD) (OR = 2.25), and hemorrhagic events (OR = 4.07). No statistically significant differences were found for gastrointestinal (GI) perforation, vascular events, fatal events, or febrile neutropenia. CONCLUSIONS: Bevacizumab did increase the risk of LVD and hemorrhagic events. The addition of bevacizumab to chemotherapy in patients with metastatic breast cancer was not associated with a significant increase in grade ≥ 3 arterial or venous thromboembolic events, GI perforation, or fatal events.

Oligodeoxynucleotide IMT504: lack of effect on immune parameters during islet regeneration in single dose streptozotocin-induced diabetes.

BACKGROUND: We have shown that oligodeoxynucleotide IMT504 improved blood glucose and islet beta-cell content in streptozotocin (STZ)-induced diabetic rats, inducing early expression of progenitor markers. Here we determined the effect of IMT504 on islet infiltration and on immunomodulatory proteins indoleamine 2,3-dioxygenase (IDO) and TNF-α-stimulated gene/protein 6 (TSG-6) in islets of STZ-diabetic rats, at the time of progenitor markers expression. METHODS: Male rats were i.p. injected with STZ [60 mg/kg body weight (BW)] or citrate buffer (control) (day 1). Starting on day 4, STZ animals were daily treated with saline (STZ-saline) or IMT504 (20 mg/kg BW/day s.c., STZ-IMT504) and killed after two consecutive decreases in blood glucose. Islet area and insulin expression, CD3 (T lymphocytes), CD68 (macrophages), IDO and TSG-6 immunostainings were determined. Islet infiltration was also evaluated by haematoxylin staining. RESULTS: STZ-induced diabetes in rats, with an important decrease in islet area was reversed by IMT504. Diabetes development did not involve islet infiltration, determined by haematoxylin and by the absence of significant T lymphocyte and macrophage presence. IMT504 did not induce changes in these parameters. IDO was not expressed in controls; the percentages of IDO-positive islets were very low and similar in STZ-saline and STZ-IMT504. Scarce TSG-6 was expressed in all groups, without significant differences. CONCLUSIONS: IMT504 improved insulin content but did not alter IDO or TSG-6 staining in islets of STZ-diabetic rats, suggesting that they do not participate in the IMT504-induced repair process. IMT504 did not per se modify leukocyte presence in islets of diabetic rats.

Effect of HCl on the doping and shape control of silicon nanowires.

The introduction of hydrogen chloride during the in situ doping of silicon nanowires (SiNWs) grown using the vapor-liquid-solid (VLS) mechanism was investigated. Compared with non-chlorinated atmospheres, the use of HCl with dopant gases considerably improves the surface morphology of the SiNWs, leading to extremely smooth surfaces and a greatly reduced tapering. Variations in the wire diameter are massively reduced for boron doping, and cannot be measured at 600 °C for phosphorous over several tens of micrometers. This remarkable feature is accompanied by a frozen gold migration from the catalyst, with no noticeable levels of gold clusters observed using scanning electron microscopy. A detailed study of the apparent resistivity of the NWs reveals that the dopant incorporation is effective for both types of doping. A graph linking the apparent resistivity to the dopant to silane dilution ratio is built for both types of doping and discussed in the frame of the previous results.

InGaAs quantum dots grown by molecular beam epitaxy for light emission on Si substrates.

The aim of this study is to achieve homogeneous, high density and dislocation free InGaAs quantum dots grown by molecular beam epitaxy for light emission on silicon substrates. This work is part of a project which aims at overcoming the severe limitation suffered by silicon regarding its optoelectronic applications, especially efficient light emission device. For this study, one of the key points is to overcome the expected type II InGaAs/Si interface by inserting the InGaAs quantum dots inside a thin silicon quantum well in SiO2 fabricated on a SOI substrate. Confinement effects of the Si/SiO2 quantum well are expected to heighten the indirect silicon bandgap and then give rise to a type I interface with the InGaAs quantum dots. Band structure and optical properties are modeled within the tight binding approximation: direct energy bandgap is demonstrated in SiO2/Si/InAs/Si/SiO2 heterostructures for very thin Si layers and absorption coefficient is calculated. Thinned SOI substrates are successfully prepared using successive etching process resulting in a 2 nm-thick Si layer on top of silica. Another key point to get light emission from InGaAs quantum dots is to avoid any dislocations or defects in the quantum dots. We investigate the quantum dot size distribution, density and structural quality at different V/III beam equivalent pressure ratios, different growth temperatures and as a function of the amount of deposited material. This study was performed for InGaAs quantum dots grown on Si(001) substrates. The capping of InGaAs quantum dots by a silicon epilayer is performed in order to get efficient photoluminescence emission from quantum dots. Scanning transmission electronic microscopy images are used to study the structural quality of the quantum dots. Dislocation free In50Ga50As QDs are successfully obtained on a (001) silicon substrate. The analysis of QDs capped with silicon by Rutherford Backscattering Spectrometry in a channeling geometry is also presented.

Surface recombination velocity measurements of efficiently passivated gold-catalyzed silicon nanowires by a new optical method.

The past decade has seen the explosion of experimental results on nanowires grown by catalyzed mechanisms. However, few are known on their electronic properties especially the influence of surfaces and catalysts. We demonstrate by an optical method how a curious electron-hole thermodynamic phase can help to characterize volume and surface recombination rates of silicon nanowires (SiNWs). By studying the electron-hole liquid dynamics as a function of the spatial confinement, we directly measured these two key parameters. We measured a surface recombination velocity of passivated SiNWs of 20 cm s(-1), 100 times lower than previous values reported. Furthermore, the volume recombination rate of gold-catalyzed SiNWs is found to be similar to that of a high-quality three-dimensional silicon crystal; the influence of the catalyst is negligible. These results advance the knowledge of SiNW surface passivation and provide essential guidance to the development of efficient nanowire-based devices.

Overall survival for early and locally advanced non-small-cell lung cancer from one institution: 2000-2017.

PURPOSE: Lung cancer is the leading cause of cancer death in Spain. The objective of our study was to evaluate the characteristics of patients diagnosed with stages I-III non-small-cell lung cancer, as well as the impact that epidemiological changes, diagnostic improvements and surgical therapeutic innovations have had on survival in the past 20 years. METHODS: Retrospective analysis of patients diagnosed with early and locally advanced non-small-cell lung cancer between years 2000 and 2017 in our institution. RESULTS: A total of 859 patients were included. An increase in the percentage of women diagnosed over time was observed. Statistically significant differences were observed in the mean age at diagnosis, with a progressive increase in the different periods. The percentage of current or former smokers was similar in all periods. Adenocarcinoma was the most frequent histologic type with a progressive increase in its frequency. The percentage of patients diagnosed in early stages has been increasing over the years. In stages I-II, there was a significant increase in the median survival (29.7 months: 2000-2004, 68.73 months: 2010-2014) that could be seen in stage III as well (14.7 months: 2000-2004, 30.63 months: 2015-2017). CONCLUSIONS: A variation of clinical characteristics of lung cancer in Spain has been observed in recent years, as well as an improvement in survival in early and locally advanced stages, due not only to the treatments, but also to a more accurate detection of these tumors. Little progress has been made in tobacco habit with high stable percentages over the years.

Intrathecal baclofen pump exchange in multiple sclerosis. Factors affecting baclofen efficacy and dose adjustement. A case report. / Recambio de bomba intratecal en esclerosis múltiple. Factores que interfieren en la eficacia y ajuste de dosis de baclofeno. A propósito de un caso.

Multiple sclerosis is a neurological disease that presents with various symptoms; in some cases it is progressive and highly disabling, requiring invasive techniques to treat pain and spasticity. The use of intrathecal baclofen infusions is an effective and safe alternative for patients with severe and refractory spasticity. The therapy can improve quality of life, but must be performed in a pain unit by medical staff trained in the technique, its indications, pharmacology, and the potential risks of both the implant and the drug. The treatment can be individualized and patients must be followed up periodically.

KRAS p.G12C mutation occurs in 1% of EGFR-mutated advanced non-small-cell lung cancer patients progressing on a first-line treatment with a tyrosine kinase inhibitor.

BACKGROUND: KRAS is mutated in ∼30% of non-small-cell lung cancer (NSCLC) but it has also been identified as one of the mechanisms underlying resistance to tyrosine kinase inhibitors (TKIs) in EGFR-positive NSCLC patients. Novel KRAS inhibitors targeting KRAS p.G12C mutation have been developed recently with promising results. The proportion of EGFR-positive NSCLC tumours harbouring the KRAS p.G12C mutation upon disease progression is completely unexplored. MATERIALS AND METHODS: Plasma samples from 512 EGFR-positive advanced NSCLC patients progressing on a first first-line treatment with a TKI were collected. The presence of KRAS p.G12C mutation was assessed by digital PCR. RESULTS: Overall, KRAS p.G12C mutation was detected in 1.17% of the samples (n = 6). In two of these cases, we could confirm that the KRAS p.G12C mutation was not present in the pre-treatment plasma samples, supporting its role as an acquired resistance mutation. According to our data, KRASG12C patients showed similar clinicopathological characteristics to those of the rest of the study cohort and no statistically significant associations between any clinical features and the presence of the mutation were found. However, two out of six KRASG12C tumours harboured less common EGFR driver mutations (p.G719X/p.L861Q). All KRASG12C patients tested negative for the presence of p.T790M resistance mutation. CONCLUSIONS: The KRAS p.G12C mutation is detected in 1% of EGFR-positive NSCLC patients who progress on a first line with a TKI. All KRASG12C patients were negative for the presence of the p.T790M mutation and they did not show any distinctive clinical feature.

Recombination dynamics of spatially confined electron-hole system in luminescent gold catalyzed silicon nanowires.

We study by time-resolved low temperature photoluminescence (PL) experiments of the electronic states of silicon nanowires (SiNWs) grown by gold catalyzed chemical vapor deposition and passivated by thermal SiO(2). The typical recombination line of free carriers in gold-catalyzed SiNWs (Au-SiNWs) is identified and studied by time-resolved experiments. We demonstrate that intrinsic Auger recombination governs the recombination dynamic of the dense e-h plasma generated inside the NW. In a few tens of nanoseconds after the pulsed excitation, the density of the initial electronic system rapidly decreases down to reach that of a stable electron-hole liquid phase. The comparison of the PL intensity decay time of Au-SiNWs with high crystalline quality and purity silicon layer allows us to conclude that the Au-SiNW electronic properties are highly comparable to those of bulk silicon crystal.

Rapamycin-induced inhibition of the 70-kilodalton S6 protein kinase.

The immunosuppressant rapamycin inhibited proliferation of the H4IIEC hepatoma cell line. Rapamycin, but not its structural analog FK506, also inhibited the basal and insulin-stimulated activity of the p70 ribosomal protein S6 kinase. By contrast, insulin stimulation of the p85 Rsk S6 kinase and mitogen-activated protein (MAP) kinase activity were unaffected by drug. Rapamycin treatment of COS cells transfected with recombinant p70 S6 kinase completely inhibited the appearance of the hyperphosphorylated form of p70 S6 kinase concomitant with the inhibition of enzyme activity toward 40S subunits. Thus, rapamycin inhibits a signal transduction element that is necessary for the activation of p70 S6 kinase and mitogenesis but unnecessary for activation of p85 Rsk S6 kinase or MAP kinase.

The evolution of the fraction of Er ions sensitized by Si nanostructures in silicon-rich silicon oxide thin films.

Photoluminescence (PL) and time-resolved PL experiments as a function of the elaboration process are performed on Er-doped silicon-rich silicon oxide (SRO:Er) thin films grown under NH(3) atmosphere. These PL measurements of the Er(3+) emission at 1.54 microm under non-resonant pumping with the Er f-f transitions are obtained for different Er(3+) concentrations, ranging from 0.05 to 1.4 at.%, and various post-growth annealing temperatures of the layers. High resolution transmission electron microscopy (HRTEM) and energy-filtered TEM (EFTEM) analysis show a high density of Si nanostructures composed of amorphous and crystalline nanoclusters varying from 2.7 x 10(18) to 10(18) cm(-3) as a function of the post-growth annealing temperature. Measurements of PL lifetime and effective Er excitation cross section for all the samples under non-resonant optical excitation with the Er(3+) atomic energy levels show that the number of Er(3+) ions sensitized by the silicon-rich matrix decreases as the annealing temperature is increased from 500 to 1050 degrees C. The origin of this effect is attributed to the reduction of the density of sensitizers for Er ions in the SRO matrix when the annealing temperature increases. Finally, extended x-ray absorption fine-structure spectroscopy (EXAFS) shows a strong correlation between the number of emitters and the mean local order around the erbium ions.

Lasing in strained germanium microbridges.

Germanium has long been regarded as a promising laser material for silicon based opto-electronics. It is CMOS-compatible and has a favourable band structure, which can be tuned by strain or alloying with Sn to become direct, as it was found to be required for interband semiconductor lasers. Here, we report lasing in the mid-infrared region (from λ = 3.20 µm up to λ = 3.66 µm) in tensile strained Ge microbridges uniaxially loaded above 5.4% up to 5.9% upon optical pumping, with a differential quantum efficiency close to 100% with a lower bound of 50% and a maximal operating temperature of 100 K. We also demonstrate the effect of a non-equilibrium electron distribution in k-space which reveals the importance of directness for lasing. With these achievements the strained Ge approach is shown to compare well to GeSn, in particular in terms of efficiency.

Metabolism of nitrate esters by a consortium of two bacteria.

The products of condensation of organic alcohols and nitric acid are nitrate esters with the general structure C-O-NO2. These products are widely employed as vasodilators and explosives, and are true xenobiotic compounds, as they do not occur in nature. We have isolated and characterized a consortium of two microorganisms, Arthrobacter ilicis and Agrobacterium radiobacter, that mineralized recalcitrant ethylene glycol dinitrate. The Arthrobacter strain was the actual degrading microorganism, although the second microbe facilitated mineralization. The biodegradation of ethylene glycol dinitrate by A. ilicis involved the progressive elimination of the nitro groups from the organic molecule to generate ethylene glycol, which was then mineralized. Waters polluted with ethylene glycol dinitrate have been shown amenable to biological treatment in a pilot plant with wastewaters generated during the synthesis of the chemical in a factory.