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Diffusion MR Characteristics Following Concurrent Radiochemotherapy Predicts Progression-Free and Overall Survival in Newly Diagnosed Glioblastoma.
The standard of care for newly diagnosed glioblastoma (GBM) is surgery, then radiotherapy (RT) with concurrent temozolomide (TMZ), followed by adjuvant TMZ. We hypothesized patients with low diffusivity measured using apparent diffusion coefficient (ADC) histogram analysis evaluated after RT+TMZ, prior to adjuvant TMZ, would have a significantly shorter progression-free (PFS) and overall survival (OS). To test this hypothesis we evaluated 120 patients with newly diagnosed GBM receiving RT+TMZ followed by adjuvant TMZ. MRI was performed after completion of RT+TMZ, prior to initiation of adjuvant TMZ. A double Gaussian mixed model was used to describe the ADC histograms within the enhancing tumor, where ADCL and ADCH were defined as the mean ADC value of the lower and higher Gaussian distribution, respectively. An ADCL value of 1.0 um2/ms and ADCH value of 1.6 um2/ms were used to stratify patients into high and low risk categories. Results suggest patients with low ADCL had significantly shorter PFS (Cox Hazard Ratio = 0.12, P = 0.0006). OS was significantly shorter with low ADCL tumors, showing a median OS of 407 vs. 644 days (Cox Hazard Ratio = 0.31, P = 0.047). ADCH was not predictive of PFS or OS when accounting for age and ADCL. In summary, newly diagnosed glioblastoma patients with low ADCL after completion of RT+TMZ are likely to progress and die earlier than patients with higher ADCL. Results suggest ADC histogram analysis may be useful for patient risk stratification following completion of RT+TMZ
The Massive and Distant Clusters of WISE Survey V: Extended Radio Sources in Massive Galaxy Clusters at z~1
We present the results from a pilot study with the Karl G. Jansky Very Large
Array (JVLA) to determine the radio morphologies of extended radio sources and
the properties of their host-galaxies in 10 massive galaxy clusters at z~1, an
epoch in which clusters are assembling rapidly. These clusters are drawn from a
parent sample of WISE-selected galaxy clusters that were cross-correlated with
the VLA Faint Images of the Radio Sky at Twenty-Centimeters survey (FIRST) to
identify extended radio sources within 1 of the cluster centers. Out
of the ten targeted sources, six are FR II sources, one is an FR I source, and
three sources have undetermined morphologies. Eight radio sources have
associated Spitzer data, 75% presenting infrared counterparts. A majority of
these counterparts are consistent with being massive galaxies. The angular
extent of the FR sources exhibits a strong correlation with the cluster-centric
radius, which warrants further investigation with a larger sample.Comment: accepted to Ap
āSheās been a rockā: the function and importance of āholdingā by social prescribing link workers in primary care in England: findings from a realist evaluation.
Social prescribing link workers are new roles in English primary care. One of their intended functions is to address the increasing number of patients with conditions influenced by the wider, social determinants of health. Their main purpose is to connect people to community resources to meet their non-medical needs. However, our research reveals that link workers provide not only connections, but also what we have described as āholdingā for patients who have complex needs, who lack informal networks of support or who are waiting to access services. We explore the concept of holding, its meaning and significance in this context and its consequences.As part of a realist evaluation, we observed seven link workers in GP practices in England during focussed ethnographies over a three-week period. We took field notes and interviewed 61 patients and 93 healthcare professionals. Nine to twelve months later we carried out follow-up interviews with 41 patients, seven link workers and a link worker manager. We identified four functions of holding: supporting patients waiting for services, sustaining patients as they prepare for change, reducing the emotional burden of primary healthcare professionals, and bearing witness to patientsā distress. Holding appears to be a vital, but often overlooked aspect of social prescribing. Patients benefit from having a reliable and consistent person to support their emotional needs. However, similar to the impact of holding on other primary care professionals, there are unintended consequences: some link workers exceed their capacity, become over-burdened, experience burnout, and leave their job. Recognizing the importance of holding and understanding its role in link workers' primary care responsibilities are critical. If holding work is accepted as a role for link workers, providing training and support for them should be prioritized to ensure successful implementation and positive outcomes for patients, link workers and primary healthcare
Observation of Parity Nonconservation in Moller Scattering
We report a measurement of the parity-violating asymmetry in fixed target
electron-electron (Moller) scattering: A_PV = -175 +/- 30 (stat.) +/- 20
(syst.) parts per billion. This first direct observation of parity
nonconservation in Moller scattering leads to a measurement of the electron's
weak charge at low energy Q^e_W = -0.053 +/- 0.011. This is consistent with the
Standard Model expectation at the current level of precision:
sin^2\theta_W(M_Z)_MSbar = 0.2293 +/- 0.0024 (stat.) +/- 0.0016 (syst.) +/-
0.0006 (theory).Comment: Version 3 is the same as version 2. These versions contain minor text
changes from referee comments and a change in the extracted value of Q^e_W
and sin^2\theta_W due to a change in the theoretical calculation of the
bremsstrahulung correction (ref. 16
The Era of Star Formation in Galaxy Clusters
We analyze the star formation properties of 16 infrared-selected, spectroscopically confirmed galaxy clusters at 1 1.35. Using infrared luminosities measured with deep Spitzer/Multiband Imaging Photometer for Spitzer observations at 24 Ī¼m, along with robust optical + IRAC photometric redshifts and spectral-energy-distribution-fitted stellar masses, we present the dust-obscured star-forming fractions, star formation rates, and specific star formation rates in these clusters as functions of redshift and projected clustercentric radius. We find that z ~ 1.4 represents a transition redshift for the ISCS sample, with clear evidence of an unquenched era of cluster star formation at earlier times. Beyond this redshift, the fraction of star-forming cluster members increases monotonically toward the cluster centers. Indeed, the specific star formation rate in the cores of these distant clusters is consistent with field values at similar redshifts, indicating that at z > 1.4 environment-dependent quenching had not yet been established in ISCS clusters. By combining these observations with complementary studies showing a rapid increase in the active galactic nucleus (AGN) fraction, a stochastic star formation history, and a major merging episode at the same epoch in this cluster sample, we suggest that the starburst activity is likely merger-driven and that the subsequent quenching is due to feedback from merger-fueled AGNs. The totality of the evidence suggests we are witnessing the final quenching period that brings an end to the era of star formation in galaxy clusters and initiates the era of passive evolution
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