True Aneurysm of the Superficial Temporal Artery

AbstractTrue aneurysms of the superficial temporal artery are rare in contrast to false aneurysms of the superficial temporal artery. We report a case of a true aneurysm that developed spontaneously in an HIV patient. The patient was treated with surgical excision of the aneurysm with an uneventful recovery. Histology revealed a true aneurysm. Clinical presentation and treatment as well as a review of the literature are presented

A Model for Conductive Percolation in Ordered Nanowire Arrays

The combined processes of anodization and electrodeposition lead to highly ordered arrays of cylindrical nanowires. This template-based self-assembly fabrication method yields nanowires embedded in alumina. Commonly, chemical etching is used to remove the alumina and free the nanowires. However, it has been experimentally observed during the etching process that the nanowires tend to form clumps. In this work, the nanowires are modeled as elastic rods subject to surface interaction forces. The dynamics of the model give rise to the aforementioned clumping behavior which is studied via percolation theory. This work finds that percolation takes place with probability $P \sim (t-t_c)^x$, where the exponent $x = 2.8$ and $t_c$ is the time at which percolation takes place. The critical exponents which entirely determine the system are found to be for (dimension) $d = 2$, $\beta = 2.1, \gamma = 0.57, \Delta = 2.7, \alpha = -2.8, \nu = 2.4,$ and $\delta = 1.3$.Comment: 5 pages, 8 figure

Expert Panel Survey to Update the American Congress of Rehabilitation Medicine Definition of Mild Traumatic Brain Injury

Objective: As part of an initiative led by the Brain Injury Special Interest Group Mild Traumatic Brain Injury (TBI) Task Force of the American Congress of Rehabilitation Medicine (ACRM) to update the 1993 ACRM definition of mild TBI, the present study aimed to characterize current expert opinion on diagnostic considerations. Design: Cross-sectional web-based survey. Setting: Not applicable. Participants: An international, interdisciplinary group of clinician-scientists (N=31) with expertise in mild TBI completed the survey by invitation between May and July 2019 (100% completion rate). Interventions: Not applicable. Main Outcome Measures: Ratings of agreement with statements related to the diagnosis of mild TBI and ratings of the importance of various clinical signs, symptoms, test findings, and contextual factors for increasing the likelihood that the individual sustained a mild TBI, on a scale ranging from 1 (“not at all important”) to 10 (“extremely important”). Results: Men (n=25; 81%) and Americans (n=21; 68%) were over-represented in the sample. The survey revealed areas of expert agreement (eg, acute symptoms are diagnostically useful) and disagreement (eg, whether mild TBI with abnormal structural neuroimaging should be considered the same diagnostic entity as “concussion”). Observable signs were generally rated as more diagnostically important than subjective symptoms (Wilcoxon signed ranks test, Z=3.77; P&lt;.001; r=0.68). Diagnostic importance ratings for individual symptoms varied widely, with some common postconcussion symptoms (eg, fatigue) rated as unhelpful (&lt;75% of respondents indicated at least 5 out of 10 importance). Certain acute test findings (eg, cognitive and balance impairments) and contextual factors (eg, absence of confounds) were consistently rated as highly important for increasing the likelihood of a mild TBI diagnosis (≥75% of respondents indicated at least 7 out of 10). Conclusions: The expert survey findings identified several potential revisions to consider when updating the ACRM mild TBI definition, including preferentially weighing observable signs in a probabilistic framework, incorporating symptoms and test findings, and adding differential diagnosis considerations.</p

Network structure of inter-industry flows

We study the structure of inter-industry relationships using networks of money flows between industries in 20 national economies. We find these networks vary around a typical structure characterized by a Weibull link weight distribution, exponential industry size distribution, and a common community structure. The community structure is hierarchical, with the top level of the hierarchy comprising five industry communities: food industries, chemical industries, manufacturing industries, service industries, and extraction industries.Comment: 14 pages, 7 figure

Advice to Rest for More Than 2 Days After Mild Traumatic Brain Injury Is Associated With Delayed Return to Productivity: A Case-Control Study

Objectives: Recent expert agreement statements and evidence-based practice guidelines for mild traumatic brain injury (mTBI) management no longer support advising patients to “rest until asymptomatic,” and instead recommend gradual return to activity after 1–2 days of rest. The present study aimed to: (i) document the current state of de-implementation of prolonged rest advice, (ii) identify patient characteristics associated with receiving this advice, and (iii) examine the relationship between exposure to this advice and clinical outcomes.Methods: In a case-control design, participants were prospectively recruited from two concussion clinics in Canada's public health care system. They completed self-report measures at clinic intake (Rivermead Post-concussion Symptom Questionnaire, Personal Health Questionnaire-9, and Generalized Anxiety Disorder-7) as well as a questionnaire with patient, injury, and recovery characteristics and the question: “Were you advised by at least one health professional to rest for more than 2 days after your injury?”Results: Of the eligible participants (N = 146), 82.9% reported being advised to rest for more than 2 days (exposure group). This advice was not associated with patient characteristics, including gender (95% CI odds ratio = 0.48–2.91), race (0.87–6.28) age (0.93–1.01), a history of prior mTBI(s) (0.21–1.20), or psychiatric problems (0.40–2.30), loss of consciousness (0.23–2.10), or access to financial compensation (0.50–2.92). In generalized linear modeling, exposure to prolonged rest advice predicted return to productivity status at intake (B = −1.06, chi-squared(1) = 5.28, p = 0.02; 64.5% in the exposure group vs. 40.0% in the control were on leave from work/school at the time of clinic intake, 19.8 vs. 24% had partially returned, and 11.6 vs. 24% had fully returned to work/school). The exposure group had marginally (non-significantly) higher post-concussion, depression, and anxiety symptoms.Conclusions: mTBI patients continue to be told to rest for longer than expert recommendations and practice guidelines. This study supports growing evidence that prolonged rest after mTBI is generally unhelpful, as patients in the exposure group were less likely to have resumed work/school at 1–2 months post-injury. We could not identify patient characteristics associated with getting prolonged rest advice. Further exploration of who gets told to rest and who delivers the advice could inform strategic de-implementation of this clinical practice

Comparison of the COBE FIRAS and DIRBE Calibrations

We compare the independent FIRAS and DIRBE observations from the COBE in the wavelength range 100-300 microns. This cross calibration provides checks of both data sets. The results show that the data sets are consistent within the estimated gain and offset uncertainties of the two instruments. They show the possibility of improving the gain and offset determination of DIRBE at 140 and 240 microns.Comment: Accepted for publication in the Astrophysical Journal 11 pages, plus 3 figures in separate postscript files. Figure 3 has three part

Submillimeter wavelength survey of the galactic plane from l = -5 deg to l = +62 deg: Structure and energetics of the inner disk

Results from a large scale survey of the first quadrant of the Milky Way galactic plane at wavelengths of 150, 250, and 300 microns with a 10x10 arcmin beam are presented. The emission detected in the survey arises from compact sources, most of which are identified with known peaks of 5 GHz and/or CO emission, and from an underlying diffuse background with a typical angular width of approximately 0.9 deg (FWHM) which accounts for most of the emission. A total of 80 prominent discrete sources were identified and characterized, of which about half were not previously reported at far infrared wavelengths. The total infrared luminosity within the solar circle is approximately 1 to 2x10 to the 10th power L sub 0, and is probably emitted by dust that resides in molecular clouds

Realizing orders as group rings

An order is a commutative ring that as an abelian group is finitely generated and free. A commutative ring is reduced if it has no non-zero nilpotent elements. In this paper we use a new tool, namely, the fact that every reduced order has a universal grading, to answer questions about realizing orders as group rings. In particular, we address the Isomorphism Problem for group rings in the case where the ring is a reduced order. We prove that any non-zero reduced order $R$ can be written as a group ring in a unique ``maximal'' way, up to isomorphism. More precisely, there exist a ring $A$ and a finite abelian group $G$, both uniquely determined up to isomorphism, such that $R\cong A[G]$ as rings, and such that if $B$ is a ring and $H$ is a group, then $R\cong B[H]$ as rings if and only if there is a finite abelian group $J$ such that $B\cong A[J]$ as rings and $J\times H\cong G$ as groups. Computing $A$ and $G$ for given $R$ can be done by means of an algorithm that is not quite polynomial-time. We also give a description of the automorphism group of $R$ in terms of $A$ and $G$