We conducted a population-based retrospective cohort study to investigate the influence of hospital volume, delay of surgery, and both together on the long-term survival of postoperative cancer ...patients.
Using information from the Korea Central Cancer Registry from 2001 through 2005 and the National Health Insurance claim database, we determined survival for 147 682 patients who underwent definitive surgery for any of six cancers.
Regardless of cancer site, surgical patients in low- to medium-volume hospitals showed significantly worse survival adjusted hazard ratio (aHR) = 1.36–1.86 than those in high-volume hospitals in multivariable analyses. Among the latter, treatment delays > 1 month were not associated with worse survival for stomach, colon, pancreatic, or lung cancer but were for rectal aHR = 1.28; 95% confidence interval (CI), 1.17–1.40 and breast (aHR = 1.59; 95% CI, 1.37–1.84) cancer. For patients in low- to medium-volume hospitals, treatment delay was associated with worse survival for all types of cancer (aHR = 1.78–3.81).
Our findings suggest that the effect of hospital volume and surgical treatment delay on overall survival of cancer patients should be considered in formulating or revising national health policy.
Weyl fermions are hypothetical two-component massless relativistic particles in three-dimensional (3D) space, proposed by Hermann Weyl in 1929. Their band-crossing points, called 'Weyl points', carry ...a topological charge and are therefore highly robust. There has been much excitement over recent observations of Weyl points in microwave photonic crystals and the semimetal TaAs. Here, we report on the experimental observation of 'type-II' Weyl points of light at optical frequencies, with the photons having a strictly positive group velocity along one spatial direction. We use a 3D structure consisting of laser-written waveguides, and show the presence of type-II Weyl points by observing conical diffraction along one axis when the frequency is tuned to the Weyl point; and observing the associated Fermi arc-like surface states. The realization of Weyl points at optical frequencies allows these novel electromagnetic modes to be further explored in the context of linear, nonlinear, and quantum optics.
Observation of growing phase space density (PSD) peak in the outer electron radiation belt has been considered evidence for local wave‐driven acceleration as a primary cause of radiation belt ...enhancement. However, recent studies showed that strong substorm‐associated MeV electron injections can also cause significant radiation belt enhancements on fast timescales (∼10s min). Such rapid enhancements pose challenges for determining true spatial PSD profiles. To address this, we conduct a detailed spatiotemporal analysis of electron flux and PSD during an enhancement event, using Van Allen Probes data. Our analysis reveals rapid and intermittent flux enhancements. During these rapid enhancements, inbound spacecraft observed false PSD peaks, due to spacecraft's relatively slow movement. However, we identify time intervals of stable fluxes between enhancements, enabling us to determine quasi‐stationary PSD profiles with no noticeable peaks. This study provides new insights into accurate PSD analysis, critical for understanding the mechanisms underlying radiation belt enhancements.
Plain Language Summary
Radiation belt physics studies the origin and dynamics of high‐energy electrons trapped in the Earth's radiation belts. The radial profiles of these electrons' phase space density (PSD) are essential parameters for investigating their origin and dynamics. Outward‐increasing PSD profiles indicate that electrons have been transported radially (injections) from outside the radiation belt, while locally peaked profiles suggest that they were generated locally within the belt. Obtaining accurate PSD profiles is challenging due to significant temporal changes in electron flux, particularly rapid flux enhancements from injections as observed in recent studies. To examine the impact of rapid flux enhancements on PSD analysis, we closely tracked electron flux changes in space and time during an enhancement event using data from NASA's Van Allen Probes. Our results show that inbound spacecraft can observe falsely peaked PSD profiles during rapid flux enhancements, which are temporal artifacts from relatively slower spacecraft motion. By identifying time intervals of stable electron flux between enhancements, we were able to determine the true spatial PSD profiles, which overall exhibited outward‐increasing trends, consistent with injections. Our findings offer new perspective on accurately determining PSD radial profiles, which is essential for unraveling the origins of high‐energy electrons in the Earth's radiation belts.
Key Points
Rapid and intermittent electron enhancement pattern significantly impacts phase space density (PSD) analysis
Inbound spacecraft can observe a temporal PSD peak during rapid electron enhancements driven by injections
Quasi‐stationary time intervals between enhancements enable accurate determination of PSD radial profiles
Abstract Purpose Studies regarding the effects of aesthetic outcomes after breast cancer surgery on quality of life (QoL) have yielded inconsistent results. This study analyzed the aesthetic outcomes ...and QoL of women who underwent breast conserving surgery (BCS) or total mastectomy with immediate reconstruction (TMIR) using objective and validated methods. Patients and methods QoL questionnaires (EORTC QLQ-C30, BR23, and HADs) were administered at least 1 year after surgery and adjuvant therapy to 485 patients who underwent BCS, 46 who underwent TMIR, and 87 who underwent total mastectomy (TM) without reconstruction. Aesthetic results were evaluated using BCCT.core software and by a panel of physicians. Patients' body image perception was assessed using the body image scale (BIS). Results QoL outcomes, including for social and role functioning, fatigue, pain, body image, and arm symptoms, were significantly better in the BCS and TMIR groups than in the TM group (p<0.05 each). BIS was significantly better in the BCS than in the TM or TMIR group (p<0.001 each). In the BCS and TMIR groups, general QoL factors were not significantly associated with objective cosmetic outcomes, except for body image in the QLQ-BR23. In contrast, patients with poorer BIS score reported lower QoL in almost all items of the QLQ-C30, BR23, and HADS (p<0.05 each). Conclusion In conclusion, BCS and TMIR enhanced QoL compared with TM. Among BCS and TMIR patients, objectively measured cosmetic results did not affect general QoL. S elf-perception of body image seems to be more important for QoL after breast cancer surgery.
Physics of electromagnetic ion cyclotron (EMIC) waves is complicated by inclusion of heavy ions. In particular, He+ ions in the magnetosphere have long been considered to play important roles. ...Motivated by recent observations, we examine the effect of the inclusion of hot anisotropic He+ ions in addition to the usual hot anisotropic protons. We solve the kinetic dispersion relation for this examination and find the following results. First, inclusion of hot anisotropic He+ ions leads to the growth of EMIC waves at frequencies below the He+ gyrofrequency (He band) and a reduction of the EMIC wave growth rates (or damping of the waves) at frequencies between the proton and He+ gyrofrequencies (H band). Second, this effect is more dramatic for higher temperatures of He+ that would play a role in damping EMIC waves for both frequency bands and especially for cases without a He+ temperature anisotropy. Lastly, the effect is more prominent for cold plasma dominant conditions such as the region inside the plasmasphere or plume than for hot proton dominant conditions such as the region outside the plasmasphere. We propose that this last effect can at least partially explain the satellite observations indicating the preferred (though not exclusive) occurrence of He band waves inside the plasmasphere for the times when hot anisotropic He+ ions are supplied from the plasma sheet and ring current.
Key Points
Hot anisotropic He+ ions cause increase (decrease) of He+ (H+) band EMIC wave growth rates
This effect is more significant for higher temperatures of He+
It is more effective for cold plasma dominant conditions than for hot proton dominant conditions
Background: Although recent studies suggest high accuracy of breast magnetic resonance imaging (MRI) in predicting residual tumor extent after neo-adjuvant systemic treatment (NST), its use is still ...controversial. In this study, we aimed to identify predictive factors of MRI accuracy after NST to determine a subgroup of patients in whom the use of MRI provides best additional benefit. Materials and methods: Clinicopathologic and molecular profiles of breast cancer patients were investigated and their relationships with MRI accuracy were analyzed. Results: From January 2006 to February 2008, 195 patients received NST and preoperative MRI. In overall, MRI predicted residual tumor extent with higher accuracy than ultrasonography. Triple-negative (TN) tumors showed highest correlation between MRI-measured and pathologic tumor size (r = 0.781) when compared with other subtypes. Multivariate analysis showed age and HER2 expression status as independent factors predicting MRI accuracy. When patients were classified based on their age and HER2 status, relatively older patients (>45) with HER2-negative tumors showed highest MRI accuracy. This finding was further validated using an independent cohort of 63 consecutive patients. Conclusion: Age and HER2 status independently affected MRI accuracy after NST. This observation may guide more tailored approach in using MRI in breast cancer patients undergoing NST.
An organic field‐effect transistor (OFET) memory device based on pentacene is fabricated using an additional poly(α‐methyl styrene) gate dielectric layer (PαMS, see figure) that has charge‐trapping ...ability (an electret). The device has excellent non‐volatile OFET memory characteristics, believed to originate from the stored charges in PαMS layer and transferred from the semiconductor to the polymeric gate electret.
Magnetospheric compression due to impact of enhanced solar wind dynamic pressure Pdyn has long been considered as one of the generation mechanisms of electromagnetic ion cyclotron (EMIC) waves. With ...the Van Allen Probe‐A observations, we identify three EMIC wave events that are triggered by Pdyn enhancements under prolonged northward interplanetary magnetic field (IMF) quiet time preconditions. They are in contrast to one another in a few aspects. Event 1 occurs in the middle of continuously increasing Pdyn while Van Allen Probe‐A is located outside the plasmapause at postmidnight and near the equator (magnetic latitude (MLAT) ~ −3°). Event 2 occurs by a sharp Pdyn pulse impact while Van Allen Probe‐A is located inside the plasmapause in the dawn sector and rather away from the equator (MLAT ~ 12°). Event 3 is characterized by amplification of a preexisting EMIC wave by a sharp Pdyn pulse impact while Van Allen Probe‐A is located outside the plasmapause at noon and rather away from the equator (MLAT ~ −15°). These three events represent various situations where EMIC waves can be triggered by Pdyn increases. Several common features are also found among the three events. (i) The strongest wave is found just above the He+ gyrofrequency. (ii) The waves are nearly linearly polarized with a rather oblique propagation direction (~28° to ~39° on average). (iii) The proton fluxes increase in immediate response to the Pdyn impact, most significantly in tens of keV energy, corresponding to the proton resonant energy. (iv) The temperature anisotropy with T⊥ > T|| is seen in the resonant energy for all the events, although its increase by the Pdyn impact is not necessarily always significant. The last two points (iii) and (iv) may imply that in addition to the temperature anisotropy, the increase of the resonant protons must have played a critical role in triggering the EMIC waves by the enhanced Pdyn impact.
Key Points
Three EMIC wave events triggered by various dynamic pressure conditions
Exhibit proton flux increases in expected resonant energy
Exhibit temperature anisotropy with T⊥ > T|| in the resonant energy
In this paper, using the multisatellite (the Van Allen Probes and two GOES satellites) observations in the inner magnetosphere, we examine two electromagnetic ion cyclotron (EMIC) wave events that ...are triggered by Pdyn enhancements under prolonged northward interplanetary magnetic field quiet time preconditions. For both events, the impact of enhanced Pdyn causes EMIC waves at multiple points. However, we find a strong spatial dependence that EMIC waves due to enhanced Pdyn impact can occur at multiple points (likely globally but not necessarily everywhere) but with different wave properties. For Event 1, three satellites situated at a nearly same dawnside zone but at slightly different L shells see occurrence of EMIC waves but in different frequencies relative to local ion gyrofrequencies and with different polarizations. These waves are found inside or at the outer edge of the plasmasphere. Another satellite near noon observes no dramatic EMIC wave despite the strongest magnetic compression there. For Event 2, the four satellites are situated at widely separated magnetic local time zones when they see occurrence of EMIC waves. They are again found at different frequencies relative to local ion gyrofrequencies with different polarizations and all outside the plasmasphere. We propose two possible explanations that (i) if triggered by enhanced Pdyn impact, details of ion cyclotron instability growth can be sensitive to local plasma conditions related to background proton distributions, and (ii) there can be preexisting waves with a specific spatial distribution, which determines occurrence and specific properties of EMIC waves depending on satellite's relative position after an enhanced Pdyn arrives.
Key Points
Examined EMIC waves at multiple points in the inner magnetosphere for enhanced dynamic pressure
Wave occurrences, frequencies, and polarizations differ significantly at different spatial points
Suggest explanations for the sensitive spatial dependence
L-ascorbate (L-ascorbic acid, vitamin C) clearly has an inhibitory effect on cancer cells. However, the mechanism underlying differential sensitivity of cancer cells from same tissue to L-ascorbate ...is yet to be clarified. Here, we demonstrate that L-ascorbate has a selective killing effect, which is influenced by sodium-dependent vitamin C transporter 2 (SVCT-2) in human breast cancer cells. Treatment of human breast cancer cells with L-ascorbate differentially induced cell death, dependent on the SVCT-2 protein level. Moreover, knockdown of endogenous SVCT-2 via RNA interference in breast cancer cells expressing high levels of the protein induced resistance to L-ascorbate treatment, whereas transfection with SVCT-2 expression plasmids led to enhanced L-ascorbate chemosensitivity. Surprisingly, tumor regression by L-ascorbate administration in mice bearing tumor cell xenograft also corresponded to the SVCT-2 protein level. Interestingly, SVCT-2 expression was absent or weak in normal tissues, but strongly detected in tumor samples obtained from breast cancer patients. In addition, enhanced chemosensitivity to L-ascorbate occurred as a result of caspase-independent autophagy, which was mediated by beclin-1 and LC3 II. In addition, treatment with N-acetyl-L-cysteine, a reactive oxygen species (ROS) scavenger, suppressed the induction of beclin-1 and LC3 II, implying that the differential SVCT-2 protein-dependent L-ascorbate uptake was attributable to intracellular ROS induced by L-ascorbate, subsequently leading to autophagy. These results suggest that functional SVCT-2 sensitizes breast cancer cells to autophagic damage by increasing the L-ascorbate concentration and intracellular ROS production and furthermore, SVCT-2 in breast cancer may act as an indicator for commencing L-ascorbate treatment.
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