Abstract Background Information is scarce regarding the impact of treatment on Health-Related Quality of Life (HRQL) of patients with Head and Neck (H&N) cancers. We assessed the effect of treatment ...on HRQL and its association with prognosis in H&N cancer. Patients and Methods Patients with H&N cancer in whom HRQL was assessed before and after treatment. The European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and QLQ-H&N35 instruments were used. Association of changes in patients’ HRQL after treatment with Loco-Regional Recurrence (LRR) and Overall Survival (OS) was investigated. Results One hundred sixty patients were included; scales of the baseline assessment of HRQL were moderately associated with LRR and OS, but the impact of treatment on most HRQL scales was strongly associated with OS. By multivariate analysis, baseline assessment of Global Health, Physical, HN Teeth, HN Dry mouth, and HN Cough scales, and impact of treatment on the Physical and Pain scales comprised independent variables associated with LRR. Male gender, positive lymph nodes, baseline assessment of Role, HN Pain, HN Cough, and impact of treatment on Emotion, Pain, Financial, HN Swallowing, HN Social contact, and the interaction of HN Pain-change in Pain scales were associated with OS. Both multivariate models were adjusted by the neoplasm’s site of origin. Conclusion Aside from well-known clinical-pathologic prognostic factors in H&N cancers, HRQL assessment, both prior to and after treatment, provides significant prognostic information and should be measured. Design of therapeutic clinical trials in patients with H&N cancers should consider these novel prognostic factors.
•Snow from central Antarctica offers unique advantages for cosmic dust collection.•Flux measurements with accurate control on the exposure parameter were performed.•The micrometeorites size ...distributions are measured down to 30 μm.•New constraints on the annual accretion of interplanetary dust by Earth inferred.•Melted/un-melted particles proportion indicates the origin of cosmic dust at 1 AU.
The annual flux of extraterrestrial material on Earth is largely dominated by sub-millimetre particles. The mass distribution and absolute value of this cosmic dust flux at the Earth's surface is however still uncertain due to the difficulty in monitoring both the collection efficiency and the exposure parameter (i.e. the area-time product in m2.yr). In this paper, we present results from micrometeorite collections originating from the vicinity of the CONCORDIA Station located at Dome C (Antarctica), where we performed several independent melts of large volumes of ultra-clean snow. The regular precipitation rate and the exceptional cleanliness of the snow from central Antarctica allow a unique control on both the exposure parameter and the collection efficiency. A total of 1280 unmelted micrometeorites (uMMs) and 808 cosmic spherules (CSs) with diameters ranging from 30 to 350 μm were identified. Within that size range, we measured mass fluxes of 3.0 μg.m−2.yr−1 for uMMs and 5.6 μg.m−2.yr−1 for CSs. Extrapolated to the global flux of particles in the 12-700 μm diameter range, the mass flux of dust at Earth's surface is 5,200±12001500 tons.yr−1 (1,600±500 and 3,600±7001000 tons.yr−1 of uMMs and CSs, respectively). We indicate the statistical uncertainties expected for collections with exposure parameters in the range of 0.1 up to 105 m2.yr. In addition, we estimated the flux of altered and unaltered carbon carried by heated and un-heated particles at Earth's surface. The mass distributions of CSs and uMMs larger than 100 μm are fairly well reproduced by the CABMOD-ZoDy model that includes melting and evaporation during atmospheric entry of the interplanetary dust flux. These numerical simulations suggest that most of the uMMs and CSs originate from Jupiter family comets and a minor part from the main asteroid belt. The total dust mass input before atmospheric entry is estimated at 15,000 tons.yr−1. The existing discrepancy between the flux data and the model for uMMs below 100 μm suggests that small fragile uMMs may evade present day collections, and/or that the amount of small interplanetary particles at 1 AU may be smaller than expected.
•PV passive cooling system is improved by modifying heatsink geometric parameters.•A discontinuous finned heatsink design is used for multi-directional airflow.•PV module temperature reduced up to ...5.1 °C in experimental testing.•The proposed heatsink design reduced pressure drop by up to 49%.•A discontinuous fin heatsink profile resulted in a more stable thermal response.
In this work, an improved CFD model based on previous results is used to evaluate the scaling effects on thermal and hydraulic performance of a passive heatsink design for PV panel cooling purposes. PV systems efficiency degrades when operating temperature increases, a common incidence in hot climates exposed to high solar irradiance. In order to reduce the operating temperature of PV modules and maintain their efficiency, a segmented fin heatsink is proposed, whose performance under varying wind attack conditions outperforms the conventional continuous fin profile heatsink design. Numerical simulations using computational fluid dynamics software are presented, assessing different levels of heatsink fin segmentation (fin width) and its effect on hydraulic performance, as well as temperature level and homogeneity of the PV module. Two prototypes were built for experimental evaluation: the model with better results in the numerical tests, and a conventional design homologue, both manufactured following a cost-effective ratio and using 22-gauge aluminum sheet. Numerical simulation showed a temperature reduction of up to 7 °C using the proposed heatsink, as well as a lower temperature gradient. Regarding hydraulic performance, the segmented fin profile reduces pressure losses up to 49% when compared to a conventional heatsink. Experimental results are in good agreement, as thermal images showed a mean temperature reduction of around 5 °C and similar homogeneity. The proposed heatsink design shows improved hydraulic characteristics, thus enhancing heat transfer using the same amount of material as a conventional design.
GPR142 is an islet-enriched G protein-coupled receptor that has been investigated as a novel therapeutic target for the treatment of type 2 diabetes by virtue of its insulin secretagogue activity. ...However, the signaling pathways downstream of GPR142 and whether its stimulation of insulin release is glucose-dependent remain poorly characterized. In this study, we show that both native and synthetic GPR142 agonists can activate Gq as well as Gi signaling when GPR142 is recombinantly expressed in HEK293 cells. However, in primary pancreatic islets, a native cellular system, the insulin secretagogue activity of GPR142 agonists only requires Gq activation. In addition, our results show that stimulation of insulin secretion by GPR142 in pancreatic islets is strictly glucose-dependent.
We report the detection of intense emission from magnesium and iron in Mars' atmosphere caused by a meteor shower following Comet Siding Spring's close encounter with Mars. The observations were made ...with the Imaging Ultraviolet Spectrograph, a remote sensing instrument on the Mars Atmosphere and Volatile EvolutioN spacecraft orbiting Mars. Ionized magnesium caused the brightest emission from the planet's atmosphere for many hours, resulting from resonant scattering of solar ultraviolet light. Modeling suggests a substantial fluence of low‐density dust particles 1–100 µm in size, with the large amount and small size contrary to predictions. The event created a temporary planet‐wide ionospheric layer below Mars' main dayside ionosphere. The dramatic meteor shower response at Mars is starkly different from the case at Earth, where a steady state metal layer is always observable but perturbations caused by even the strongest meteor showers are challenging to detect.
Key Points
MAVEN/IUVS observed bright emission from vaporized dust in Mars' atmosphere
The dust originated in an intense meteor shower caused by Comet Siding Spring
Mars appears to respond to meteor ablation very differently than Earth does
Redox cycles of manganese oxides (Mn2O3/Mn3O4) are a promising alternative for thermochemical heat storage systems coupled to concentrated solar power plants as manganese oxides are abundant and ...inexpensive materials. Although their cyclability for such a purpose has been proved, sintering processes, related to the high‐temperature conditions at which charge–discharge cycles are performed, generally cause a cycle‐to‐cycle decrease in the oxidation rate of Mn3O4. To guarantee proper operation, both reactions should present stable reaction rates. In this study, it has been demonstrated that the incorporation of Fe, which is also an abundant material, into the manganese oxides improves the redox performance of this system by increasing the heat storage density, narrowing the redox thermal hysteresis, and, above all, stabilizing and enhancing the oxidation rate over long‐term operation, which counteracts the negative effects caused by sintering, although its presence is not avoided.
Iron out the creases: The performance of the Mn2O3/Mn3O4 redox couple for thermochemical heat storage is improved significantly by Fe incorporation. The presence of such metal cations is especially beneficial to enhance the oxidation kinetics and counteracts the limitations caused by particle sintering. In particular, addition of 20 % Fe boosts the efficiency, resulting in high cyclability, improved kinetics, and an elevated energy storage density.
This paper introduces a CMOS operational amplifier with rail-to-rail input and output voltage ranges, suitable for operation in extremely low-voltage environments. The approach is based on a ...bulk-driven input stage with extended input common-mode voltage range, in which the effective input transconductance is enhanced by means of a partial positive feedback loop. As a result, a gain and gain-bandwidth product performance similar to that of an amplifier using a gate-driven approach is obtained. Output rail-to-rail operation is achieved by means of a push-pull stage, which is biased in class-AB by using a static feedback loop, thus avoiding frequency limitations inherent in dynamic-feedback tuning schemes. The proposed two-stage operational amplifier was designed to operate with a 1-V supply, and a test chip prototype was fabricated in 0.35-mum standard CMOS technology. The experimental performance features an open-loop DC gain higher than 76 dB and a closed-loop unity-gain bandwidth above 8 MHz when a 1-MOmegapar17-pF load is connected to the amplifier output.
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