In this letter, we present the performance of a 100 μm × 400 μm × 40 nm W Transition-Edge Sensor with a critical temperature of 40 mK. This device has a noise equivalent power of 1.5×10-18 W/Hz, in a ...bandwidth of 2.6 kHz, indicating a resolution for Dirac delta energy depositions of 40 ± 5 meV (rms). The performance demonstrated by this device is a critical step toward developing a O(100) meV threshold athermal phonon detector for low-mass dark matter searches.
ABSTRACT
We studied a suitable procedure for preparing of water samples used in radiocarbon intercomparisons involving dissolved inorganic carbon (DIC). The water samples must have inter-batch ...consistency and stable
14
C concentrations and no sterilizing agent (e.g., HgCl
2
) should be added, in order to avoid the production of hazardous material. Six water samples, containing widely different amounts and types of salts, DIC, and
14
C concentrations (1–100 pMC), were prepared in order to assess the procedure. Sample consistency was investigated through δ
13
C and chemical compositions; their low variabilities indicate that our procedure can be applied to radiocarbon intercomparison. A specific sample preparation protocol was developed for this kind of applications.
AX J1745.6-2901 is a high-inclination (eclipsing) neutron star low-mass X-ray binary (LMXB) located less than ~1.5 arcmin from Sgr A... Ongoing monitoring campaigns have targeted Sgr A... frequently ...and these observations also cover AX J1745.6-2901. We present here an X-ray analysis of AX J1745.6-2901 using a large data set of 38 XMM-Newton observations, including 11 which caught AX J1745.6-2901 in outburst. Fe K absorption is clearly seen when AX J1745.6-2901 is in the soft state, but disappears during the hard state. The variability of these absorption features does not appear to be due to changes in the ionizing continuum. The small Kα/Kβ ratio of the equivalent widths of the Fe XXV and Fe XXVIlines suggests that the column densities and turbulent velocities of the absorbing ionized plasma are in excess of N... ... 10... cm... and v... ... 500 km s... These findings strongly support a connection between the wind (Fe K absorber) and the accretion state of the binary. These results reveal strong similarities between AX J1745.6-2901 and the eclipsing neutron star LMXB, EXO 0748-676, as well as with high-inclination black hole binaries, where winds (traced by the same Fe K absorption features) are observed only during the accretion-disc-dominated soft states, and disappear during the hard states characterized by jet emission. (ProQuest: ... denotes formulae/symbols omitted.)
Background
The length of tumour–vein contact between the portal–superior mesenteric vein (PV/SMV) and pancreatic head cancer, and its relationship to prognosis in patients undergoing pancreatic ...surgery, remains controversial.
Methods
Patients diagnosed with pancreatic head cancer who were eligible for pancreatoduodenectomy between October 2002 and December 2016 were analysed. The PV/SMV contact was assessed retrospectively on CT. Using the minimum P value approach based on overall survival after surgery, the optimal cut‐off value for tumour–vein contact length was identified.
Results
Among 491 patients included, 462 underwent pancreatoduodenectomy for pancreatic head cancer. PV/SMV contact with the tumour was detected on preoperative CT in 248 patients (53·7 per cent). Overall survival of patients with PV/SMV contact exceeding 20 mm was significantly worse than that of patients with a contact length of 20 mm or less (median survival time (MST) 23·3 versus 39·3 months; P = 0·012). Multivariable analysis identified PV/SMV contact longer than 20 mm as an independent predictor of poor survival, whereas PV/SMV contact greater than 180° was not a predictive factor. Among patients with a PV/SMV contact length exceeding 20 mm on pretreatment CT, those receiving neoadjuvant therapy had significantly better overall survival than patients who had upfront surgery (MST not reached versus 21·6 months; P = 0·002).
Conclusion
The length of PV/SMV contact predicts survival, and may be used to suggest a role for neoadjuvant therapy to improve prognosis.
Antecedentes
El valor pronóstico de la longitud del contacto del tumor de la cabeza pancreática con las venas porta y mesentérica superior (portal‐superior mesenteric vein, PV/SMV) en los pacientes sometidos a cirugía pancreática sigue siendo un tema controvertido.
Métodos
Se analizaron los pacientes diagnosticados de un cáncer de la cabeza pancreática a los que se realizó una duodenopancreatectomía cefálica entre octubre de 2002 y diciembre de 2016. El contacto tumoral con la PV/SMV se evaluó de forma retrospectiva mediante tomografía computarizada (TC). Se identificó el valor de corte óptimo para la longitud del contacto tumoral con la PV/SMV, utilizando el valor mínimo de la P basado en la supervivencia global (overall survival, OS) después de la cirugía.
Resultados
De 491 pacientes incluidos, en 462 pacientes se realizó una duodenopancreatectomía cefálica por cáncer de la cabeza de páncreas. En la TC preoperatoria, se detectó contacto tumoral con la PV/SMV en 248 (53,7%) pacientes. La OS de los pacientes en los que el contacto del tumor con la PV/SMV fue > 20 mm fue significativamente peor que en aquellos cuyo contacto fue ≤ 20 mm (mediana de supervivencia (median survival time, MST) 23,3 versus 39,3 meses; P = 0,012). En un análisis multivariado se identificó el contacto tumoral‐PV/SMV > 20 mm como un factor independiente predictor de mala supervivencia, pero el contacto tumor‐PV/SMV > 180° no fue un factor pronóstico. En los pacientes en los que el contacto tumor‐PV/SMV fue > 20 mm en el TC preoperatorio, la OS en aquellos que recibieron tratamiento neoadyuvante fue significativamente mejor en comparación con los pacientes tratados directamente con cirugía (MST, no alcanzada versus 21,6 meses, P = 0,002).
Conclusión
La longitud del contacto tumoral con la PV/SMV predice la supervivencia, por lo cual dicha longitud podría jugar un papel en la indicación de tratamiento neoadyuvante para mejorar el pronóstico.
The present study aimed primarily to investigate surgical outcomes and survival among patients who had pancreatic head cancer with portal–superior mesenteric vein (PV/SMV) contact on preoperative or pretreatment CT, with a focus on the length of contact. It successfully demonstrated that the PV/SMV contact length was closely associated with prognosis, whereas analysis with the conventional focus on degrees of contact found no difference in survival.
Length of contact matters
The General Antiparticle Spectrometer (GAPS) is an Antarctic balloon experiment designed for low-energy (0.1–0.3 GeV/n) cosmic antinuclei as signatures of dark matter annihilation or decay. GAPS is ...optimized to detect low-energy antideuterons, as well as to provide unprecedented sensitivity to low-energy antiprotons and antihelium nuclei. The novel GAPS antiparticle detection technique, based on the formation, decay, and annihilation of exotic atoms, provides greater identification power for these low-energy antinuclei than previous magnetic spectrometer experiments. This work reports the sensitivity of GAPS to detect antihelium-3 nuclei, based on full instrument simulation, event reconstruction, and realistic atmospheric influence simulations. The report of antihelium nuclei candidate events by AMS-02 has generated considerable interest in antihelium nuclei as probes of dark matter and other beyond the Standard Model theories. GAPS is in a unique position to detect or set upper limits on the cosmic antihelium nuclei flux in an energy range that is essentially free of astrophysical background. In three 35-day long-duration balloon flights, GAPS will be sensitive to an antihelium flux on the level of 1.3−1.2+4.5·10−6 m-2sr-1s-1(GeV/n)-1 (95% confidence level) in the energy range of 0.11–0.3 GeV/n, opening a new window on rare cosmic physics.
We examined the spatial distributions of 226Ra, 228Ra, 134Cs, and 137Cs concentrations (activities) in seawater off the western and southern Korean Peninsula in July 2014. Radium-228 (and 226Ra) ...concentrations in water samples varied widely from 5 to 14 mBq/L (2–4 mBq/L), showing a negative correlation with salinity, particularly at the surface off the western Korean Peninsula. This indicates that the seawaters in this area are fundamentally comprised of 228Ra-poor and high-saline Kuroshio Current water and 228Ra-rich and low-saline water (e.g., continental shelf water), with various mixing ratios. Although Fukushima Dai-ichi Nuclear Power Plant (FDNPP)-derived 134Cs was below the detection limit (<0.08 mBq/L) in waters off the western Korean Peninsula, low level 134Cs (0.1–0.2 mBq/L) was detected in waters off the southern Korean Peninsula accompanied by higher 137Cs concentrations (1.6–1.9 mBq/L) relative to that off the western Korean Peninsula. Combined with the lower radium concentrations, the detection of 134Cs is explained by mixing of FDNPP-derived radiocesium-contaminated Kuroshio Current water.
•We determined radium and radiocesium in seawater around the Korean Peninsula in 2014.•Radium concentrations were governed by the mixing ratio of Kuroshio Current water.•134Cs (0.1–0.2 mBq/L) was detected at the surface of the southern Korean Peninsula.•134Cs level was negligible due to the low concentration in the Kuroshio Current.
The general antiparticle spectrometer (GAPS) experiment is a proposed indirect dark matter search focusing on antiparticles produced by WIMP (weakly interacting massive particle) annihilation and ...decay in the Galactic halo. In addition to the very powerful search channel provided by antideuterons (Donato et al., 2000, 2008) 1,2, (Vittino et al.) 3, (Fornengo, 2013) 4, GAPS has a strong capability to measure low-energy antiprotons (0.07⩽E⩽0.25GeV) as dark matter signatures. This is an especially effective means for probing light dark matter, whose existence has been hinted at in the direct dark matter searches, including the recent result from the CDMS-II experiment (Agnese, 2013) 5. While severely constrained by LUX and other direct dark matter searches (Akerib et al.) 6, light dark matter candidates are still viable in an isospin-violating dark matter scenario and halo-independent analysis (Del Nobile et al.) 7,8. Along with the excellent antideuteron sensitivity, GAPS will be able to detect an order of magnitude more low-energy antiprotons, compared to BESS (Abe et al., 2012) 9, (Orito et al., 2000) 10, PAMELA (Adriani et al., 2010) 11 and AMS-02 (Casaus, 2009) 12, providing a precision measurement of low-energy antiproton flux and a unique channel for probing light dark matter models. Additionally, dark matter signatures from gravitinos and Kaluza–Klein right-handed neutrinos as well as evidence of primordial black hole evaporation can be observed through low-energy antiproton search.
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