Carbon nanotube (CNT) thin-film thermophones, at sufficiently high input power levels, suffer from thermal saturation where an increase in the input power does not result in a corresponding increase ...in the sound pressure level generated. It is believed that high temperature air, trapped in and around the CNT film, inhibits the ability of the CNT film to cool sufficiently between heating cycles, thus limiting the sound pressure output and increasing in severity with both input power and frequency. Thermal saturation appears to be particularly acute for CNT thermophones designed for compactness or when placed inside a protective or loudspeaker enclosure, where natural convection or heat transfer from the film is inhibited. Fan cooling was integrated into a CNT thermophone and demonstrated to both reduce the temperature of the CNT film and suppress, almost entirely, the effects of thermal saturation.
The diffusion of deuterated hexane in conformational isomers of a heterogeneous polymer, H12MDI (4,4‘-dicyclohexylmethane diisocyanate)/BD (1,4-butanediol)/PTMO (poly(tetramethylene oxide)), was ...investigated at a fixed hard segment content of 30 wt % and compared to the diffusion of acetonitrile. The effective diffusion coefficient of acetonitrile decreases with increasing trans−trans isomer content while that for deuterated hexane remains constant. These results suggest that the trend observed from acetonitrile diffusion is a function of penetrant−polymer interactions and not tortuosity effects. A model with penetrant−polymer binding to the surface of the dispersed hard segment domains of the heterogeneous polymer was developed to elucidate the main factors contributing to the interaction or hindrance effect, which were determined to be the “available” surface binding sites and the surface-to-volume ratio of the hard segment domains. FTIR-ATR spectroscopy was used to quantify this interaction effect, and SAXS was used to confirm the findings.
A long record of atmospheric C-14 concentration, from 45 to 11 thousand years ago (ka), was obtained from a stalagmite with thermal-ionization mass-spectrometric Th-230 and accelerator ...mass-spectrometric C-14 measurements. This record reveals highly elevated Delta C-14 between 45 and 33 ka, portions of which may correlate with peaks in cosmogenic Cl-36 and Be-10 isotopes observed in polar ice cores. Superimposed on this broad peak of Delta C-14 are several rapid excursions, the largest of which occurs between 44.3 and 43.3 ka. Between 26 and 11 ka, atmospheric Delta C-14 decreased from about 700 to about 100 per mil, modulated by numerous minor excursions. Carbon cycle models suggest that the major features of this record cannot be produced with solar or terrestrial magnetic field modulation alone but also require substantial fluctuations in the carbon cycle. (Author)
Efforts to extract weak geomagnetic excursion signals from Chinese loess-paleosol 10Be have generally been unsuccessful due to the complexities of its accumulation, because the geomagnetic and ...climate (precipitation and dust) signals contained in loess-paleosol sequence are tightly overprinted. Here, we present a reconstruction of geomagnetic relative paleointensities for the past 130 kyr from 10Be records in 2 Chinese loess-paleosol sections using a correction based on the correlation of 10Be with magnetic susceptibility (SUS) to remove the climatic contamination. Both these records reveal the Laschamp and Blake events, which lie in the loess and paleosol (L1SS1 and S1SS3) horizons corresponding to mid-MIS 3 and 5e, respectively. The good agreement between our results and other geomagnetic intensities reconstructions from Atlantic and Pacific sediments indicates that our method is robust. Our study suggests the potential application of loess-paleosol 10Be for reconstructing geomagnetic intensity variations spanning the whole Quaternary.
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Background: Randomized phase III clinical trial data (S8710) supports an overall survival (OS) advantage with neo-CTx for muscle-invasive urothelial carcinoma (miUC) patients (pts) ...prior to cystectomy. Recent S8710 subset analyses have demonstrated an OS for pts with both pure UC and VarHst. pCR to neo-CTx has been suggested as a surrogate endpoint for OS. The relationship between VarHist in TURBT specimens and pCR rates is uncertain. Methods: A retrospective review of the Indiana University Simon Cancer Center urology and medical oncology clinical databases was performed spanning the years 1991 – 2012. Subjects with miUC, pathology reports available for both TURBT and cystectomy procedures, and confirmed receipt of neo-CTx with regimen details were included in this analysis. Pts with clinically positive lymph nodes (LN+) were included provided they underwent cystectomy with curative intent and distant metastases were not present. Associations between pCR and pt baseline age, gender, race, clinical stage (T2N0 vs. T3/T4/N+), chemotherapy regimen received (cisplatin combination therapy (CisCTx) vs. non-cisplatin based), and presence of VarHst on TURBT sample were tested by multinomial logistic regression analysis with statistical significance set at p<0.05. Results: 72 miUC pts satisfying the inclusion criteria were identified. Cohort demographics included: age (median) – 59 yrs, 76% male, 93% Caucasian, 63% T2N0, 32% LN+, 81% CisCTx neo-CTx regimen, 42% VarHst on TURBT, pCR for entire cohort 18%. The presence of VarHst on TURBT sample was not associated with decreased rates of pCR (6/30 vs. 7/42) p=0.610. A trend toward significance with age over 59 was also observed. Conclusions: The presence of VarHst in TURBT specimen is not associated with decreased rates of pCR at cystectomy in miUC pts treated with neo-CTx. Further characterization of the amount of VarHst and reproducibility of its recognition in TURBT samples is warranted to determine its ultimate clinical value.
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Background: Despite an improved overall survival with neo-CTx for muscle-invasive urothelial carcinoma (miUC) patients (pts) prior to cystectomy, the adoption of neo-CTx in suitable ...pts has been suboptimal. While associated with a more aggressive phenotype in early stage UC, the prognostic role of CIS in miUC is less clear. In particular, the effect of concurrent CIS in pts undergoing neo-CTx prior to cystectomy is unknown. Methods: A retrospective review of the Indiana University Simon Cancer Center urology and medical oncology clinical databases was performed spanning the years 1991 – 2012. Subjects with miUC, pathology reports available for both transurethral resection of bladder tumor (TURBT) and cystectomy procedures, and confirmed receipt of neo-CTx were included in this analysis. Pts with clinically positive lymph nodes (LN+) were included provided they underwent cystectomy with curative intent. Associations between pCR and pt baseline age, gender, race, clinical stage (T2N0 vs. T3/T4/N+), chemotherapy regimen received (cisplatin combination therapy (CisCTx) vs. non-cisplatin based), and presence of CIS on TURBT sample were tested by multinomial logistic regression analysis with statistical significance set at p<0.05. Results: 72 miUC pts satisfying the inclusion criteria were identified. Cohort demographics included: median age – 59 yrs, 76% male, 93% Caucasian, 63% T2N0, 32% LN+, 81% CisCTx neo-CTx regimen, 32% CIS on TURBT, pCR for entire cohort 18%. The presence of CIS on TURBT was significantly associated with decreased rates of pCR (1/23 vs. 12/49) p=0.002. TURBT CIS was not associated with decreased rates of less than pT2N0 (12/23 vs. 18/49) p=0.562. Seven pts (30%) with CIS on TURBT sample achieved pTisN0 at cystectomy. Conclusions: The presence of CIS in TURBT specimens is associated with decreased rates of pCR at cystectomy in miUC pts treated with neo-CTx. The finding of pTisN0 at cystectomy is common after neo-CTx in pts with CIS in preop TURBT specimens. Validation of the prognostic significance of TURBT CIS on pCR rates and characterization of pTisN0 clinical course in TURBT CIS pts after neo-CTx is warranted.
Abstract Background Carcinoma in situ (CIS) is a poor prognostic finding in urothelial carcinoma. However, its significance in muscle-invasive urothelial carcinoma (MIUC) patients treated with ...neoadjuvant chemotherapy (NAC) is uncertain. We assessed the impact of CIS within pre-treatment transurethral resection of bladder tumor (TURBT) biopsies on pathologic and clinical outcomes. Materials and Methods Subjects with MIUC treated with NAC prior to cystectomy were identified. Pathologic complete response rates (pCR) according to TURBT CIS status were compared. Secondary analyses included tumor response, progression-free survival (PFS), overall survival (OS), and an exploratory post-hoc analysis in patients with pathologic CIS only (pTis N0) at cystectomy. Results One hundred thirty-seven MIUC patients were identified. TURBT CIS was noted in 30.7% of subjects. The absence of TURBT CIS was associated with a significantly increased pCR rate (23.2% vs 9.5%, OR 4.08, 95% CI 1.19-13.98, p=0.0.025). pTis N0 stage was observed in 19.0% of TURBT CIS patients. TURBT CIS status did not significantly affect PFS or OS outcomes. Post-hoc analysis of pTis N0 patients revealed prolonged median PFS (104.5 vs 139.9 months, p=0.055) and OS (104.5 vs 152.3 months, p=0.091) outcomes similar to pCR patients. Conclusion The absence of CIS on pre-treatment TURBT in MIUC patients receiving NAC is associated with increased pCR rates with no observed difference in PFS or OS. Isolated CIS at cystectomy was frequently observed with lengthy PFS and OS durations similar to pCR patients. Further studies aimed at understanding the biology and clinical impact of CIS in MIUC are warranted.
The Younger Dryas chronozone, recognised in northern high-latitude areas as a cold event between 11 000 and 10 000
14C yr BP (12 900–11 600 cal. yr BP), seems to manifest itself globally in different ...ways. Here, we examine well-dated stratigraphic sequences together with high-resolution proxy data plots from sites across our study area, the arid–semi-arid transition zone in northern China. This climatically sensitive area of China records a cold, dry Younger Dryas climate which was punctuated by a brief period of summer monsoon precipitation. We have since found that similar climatic sequences have been reported from the Sahel and the equatorial region of Africa. Based on evidence from these sites, together with other published data, we postulate that precipitation during the Younger Dryas chronozone was indicative of a low-latitude driving force superimposed on the high-latitude cold background. This rain belt rearrangement was most probably caused by an interaction between cold air advection and summer moisture transport across the tropical Pacific Ocean. Examination of high-resolution proxies suggests short-term climate fluctuations indicative of a global teleconnection involving moist air transportation patterns from the tropics to higher latitudes, varying with ENSO and other tropical factors.
Sustainable Lifewaysaddresses forces of conservatism and innovation in societies dependent on the exploitation of aquatic and other wild resources, agriculture, and specialized pastoralism. The ...volume gathers specialists working in four areas of the world with significant archaeological and paleoenvironmental databases: West Asia, the American Southwest, East Africa, and Andean South America, and contributing to research in three broad time scales: long term (spanning millennia), medium term (archaeological time, spanning centuries or a few thousand years), and recent (ethnohistoric or ethnographic, spanning years or decades). By bringing an archaeological eye to an examination of human response to unpredictable environmental conditions, informed by an understanding of contemporary traditional peoples, the contributors to this volume develop a more detailed picture of how societies perceive environmental risk, how they alter their behavior in the face of changing conditions, and under what challenges the most rapid and far-reaching changes in adaptation have taken place.Sustainable Lifewaysenhances our understanding of both the forces of conservatism and innovation which may have been in play in major transitions in the past, such as the development of complex society, and the expansions of early empires. Studies present examples of cattle herders in East Africa, hunter-gatherers and pastoralists in the Levant, South American fisher/farmers, and farmer/hunters of the U.S. Southwest.
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