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Preoperative Narcotic Use, Impaired Ambulation Status, and Increased Intraoperative Blood Loss Are Independent Risk Factors for Complications Following Posterior Cervical Laminectomy and Fusion Surgery.
ObjectiveThis retrospective cohort study seeks to identify risk factors associated with complications following posterior cervical laminectomy and fusion (PCLF) surgery.MethodsAdults undergoing PCLF from 2012 through 2018 at a single center were identified. Demographic and radiographic data, surgical characteristics, and complication rates were compared. Multivariate logistic regression models identified independent predictors of complications following surgery.ResultsA total of 196 patients met the inclusion criteria and were included in the study. The medical, surgical, and overall complication rates were 10.2%, 23.0%, and 29.1% respectively. Risk factors associated with medical complications in multivariate analysis included impaired ambulation status (odds ratio [OR], 2.27; p=0.02) and estimated blood loss over 500 mL (OR, 3.67; p=0.02). Multivariate analysis revealed preoperative narcotic use (OR, 2.43; p=0.02) and operative time (OR, 1.005; p=0.03) as risk factors for surgical complication, whereas antidepressant use was a protective factor (OR, 0.21; p=0.01). Overall complication was associated with preoperative narcotic use (OR, 1.97; p=0.04) and higher intraoperative blood loss (OR, 1.0007; p=0.03).ConclusionPreoperative narcotic use and estimated blood loss predicted the incidence of complications following PCLF for CSM. Ambulation status was a significant predictor of the development of a medical complication specifically. These results may help surgeons in counseling patients who may be at increased risk of complication following surgery
Boundary-Layer Instability Measurements in a Mach-6 Quiet Tunnel
Several experiments have been performed in the Boeing/AFOSR Mach-6 Quiet Tunnel at Purdue University. A 7 degree half angle cone at 6 degree angle of attack with temperature-sensitive paint (TSP) and PCB pressure transducers was tested under quiet flow. The stationary crossflow vortices appear to break down to turbulence near the lee ray for sufficiently high Reynolds numbers. Attempts to use roughness elements to control the spacing of hot streaks on a flared cone in quiet flow did not succeed. Roughness was observed to damp the second-mode waves in areas influenced by the roughness, and wide roughness spacing allowed hot streaks to form between the roughness elements. A forward-facing cavity was used for proof-of-concept studies for a laser perturber. The lowest density at which the freestream laser perturbations could be detected was 1.07 x 10(exp -2) kilograms per cubic meter. Experiments were conducted to determine the transition characteristics of a streamwise corner flow at hypersonic velocities. Quiet flow resulted in a delayed onset of hot streak spreading. Under low Reynolds number flow hot streak spreading did not occur along the model. A new shock tube has been built at Purdue. The shock tube is designed to create weak shocks suitable for calibrating sensors, particularly PCB-132 sensors. PCB-132 measurements in another shock tube show the shock response and a linear calibration over a moderate pressure range
Chemical signatures of the first star clusters
The chemical abundance patterns of the oldest stars in the Galaxy are
expected to contain residual signatures of the first stars in the early
universe. Numerous studies attempt to explain the intrinsic abundance scatter
observed in some metal-poor populations in terms of chemical inhomogeneities
dispersed throughout the early Galactic medium due to discrete enrichment
events. Just how the complex data and models are to be interpreted with respect
to "progenitor yields" remains an open question. Here we show that stochastic
chemical evolution models to date have overlooked a crucial fact. Essentially
all stars today are born in highly homogeneous star clusters and it is likely
that this was also true at early times. When this ingredient is included, the
overall scatter in the abundance plane [Fe/H] vs. [X/Fe] (C-space), where X is
a nucleosynthetic element, can be much less than derived from earlier models.
Moreover, for moderately flat cluster mass functions (gamma < 2), and/or for
mass functions with a high mass cut-off (M_max > 10^5 M_sun), stars exhibit a
high degree of clumping in C-space that can be identified even in relatively
small data samples. Since stellar abundances can be modified by mass transfer
in close binaries, clustered signatures are essential for deriving the yields
of the first supernovae. We present a statistical test to determine whether a
given set of observations exhibit such behaviour. Our initial work focusses on
two dimensions in C-space, but we show that the clustering signal can be
greatly enhanced by additional abundance axes. The proposed experiment will be
challenging on existing 8-10m telescopes, but relatively straightforward for a
multi-object echelle spectrograph mounted on a 25-40m telescope.Comment: 24 pages, 17 figs; Astrophysical Journal (Sept 20 issue); a full copy
is available at
http://sydney.edu.au/science/physics/~jbh/share/firststarclusters.pd
Heterogeneous ice nucleation properties of natural desert dust particles coated with a surrogate of secondary organic aerosol
Ice nucleation abilities of surface collected mineral dust particles from the Sahara (SD) and Asia (AD) are investigated for the temperature (T) range 253–233 K and for supersaturated relative humidity (RH) conditions in the immersion freezing regime. The dust particles were also coated with a proxy of secondary organic aerosol (SOA) from the dark ozonolysis of α-pinene to better understand the influence of atmospheric coatings on the immersion freezing ability of mineral dust particles. The measurements are conducted on polydisperse particles in the size range 0.01–3 µm with three different ice nucleation chambers. Two of the chambers follow the continuous flow diffusion chamber (CFDC) principle (Portable Ice Nucleation Chamber, PINC) and the Colorado State University CFDC (CSU-CFDC), whereas the third was the Aerosol Interactions and Dynamics in the Atmosphere (AIDA) cloud expansion chamber. From observed activated fractions (AFs) and ice nucleation active site (INAS) densities, it is concluded within experimental uncertainties that there is no significant difference between the ice nucleation ability of the particular SD and AD samples examined. A small bias towards higher INAS densities for uncoated versus SOA-coated dusts is found but this is well within the 1σ (66 % prediction bands) region of the average fit to the data, which captures 75 % of the INAS densities observed in this study. Furthermore, no systematic differences are observed between SOA-coated and uncoated dusts in both SD and AD cases, regardless of coating thickness (3–60 nm). The results suggest that any differences observed are within the uncertainty of the measurements or differences in cloud chamber parameters such as size fraction of particles sampled, and residence time, as well as assumptions in using INAS densities to compare polydisperse aerosol measurements which may show variable composition with particle size. Coatings with similar properties to that of the SOA in this work and with coating thickness up to 60 nm are not expected to impede or enhance the immersion mode ice nucleation ability of mineral dust particles.ISSN:1680-7375ISSN:1680-736
Optimal design of pre-control plans
[EN] Pre-control is a quality tool for quick set-up approvals, especially used in short-run processes. It is based on specifications instead of on the natural variability of the process and uses cumulative counts in order to yield a conclusion. Its main drawbacks are a high false alarm rate and a low power to detect process deviations, under certain circumstances. These issues can be addressed by making the technique more flexible, as shown in previous works. In this paper, we introduce a Mathematical Programming approach in order to optimally determine the value of the pre-control parameters, so that it can meet the user s requirements while minimizing the sample size of the technique as much as possible. We propose and develop a mathematical model for optimal pre-control and perform some numerical experiments in order to show its effectiveness.The research by V. Giner-Bosch and M. Clemente-Ciscar was partially supported by the Ministerio de Ciencia e Innovacion of Spain under grant no. MTM2013-45381-P.Giner-Bosch, V.; San Matías Izquierdo, S.; Clemente-Císcar, M.; Carrión García, A. (2016). Optimal design of pre-control plans. Quality and Reliability Engineering International. 32(2):623-634. https://doi.org/10.1002/qre.1777S62363432
PARP-1 dependent recruitment of the amyotrophic lateral sclerosis-associated protein FUS/TLS to sites of oxidative DNA damage
Amyotrophic lateral sclerosis (ALS) is associated with progressive degeneration of motor neurons. Several of the genes associated with this disease encode proteins involved in RNA processing, including fused-in-sarcoma/translocated-in-sarcoma (FUS/TLS). FUS is a member of the heterogeneous nuclear ribonucleoprotein (hnRNP) family of proteins that bind thousands of pre-mRNAs and can regulate their splicing. Here, we have examined the possibility that FUS is also a component of the cellular response to DNA damage. We show that both GFP-tagged and endogenous FUS re-localize to sites of oxidative DNA damage induced by UVA laser, and that FUS recruitment is greatly reduced or ablated by an inhibitor of poly (ADP-ribose) polymerase activity. Consistent with this, we show that recombinant FUS binds directly to poly (ADP-ribose) in vitro, and that both GFP-tagged and endogenous FUS fail to accumulate at sites of UVA laser induced damage in cells lacking poly (ADP-ribose) polymerase-1. Finally, we show that GFP-FUS(R521G), harbouring a mutation that is associated with ALS, exhibits reduced ability to accumulate at sites of UVA laser-induced DNA damage. Together, these data suggest that FUS is a component of the cellular response to DNA damage, and that defects in this response may contribute to ALS
Interaction Between Pre- and Post-Migration Factors on Depressive Symptoms in New Migrants to Hong Kong from Mainland China
The goal of the current study is to examine the role of poor migration planning as a moderator for the effects of two post-migration factors, namely acculturation stress and quality of life, on symptoms of depression. Using a random sample of 347 Hong Kong new migrants from a 1-year longitudinal study, we used multiple regression analyses to examine both the direct and interaction effects of poorly planned migration, acculturation stress, and quality of life on depressive symptoms. Although poorly planned migration did not predict depressive symptoms at 1-year follow-up, it did exacerbate the detrimental effect of the two post-migration factors, namely high stress or low quality of life (both also measured at baseline) on depressive symptoms at this stage. Our results indicate that preventive measures must be developed for new immigrants in Hong Kong, especially for those who were not well prepared for migration
Angular Momentum and Vortex Formation in Bose-Einstein-Condensed Cold Dark Matter Haloes
(Abridged) Extensions of the standard model of particle physics predict very
light bosons, ranging from about 10^{-5} eV for the QCD axion to 10^{-33} eV
for ultra-light particles, which could be the cold dark matter (CDM) in the
Universe. If so, their phase-space density must be high enough to form a
Bose-Einstein condensate (BEC). The fluid-like nature of BEC-CDM dynamics
differs from that of standard collisionless CDM (sCDM), so observations of
galactic haloes may distinguish them. sCDM has problems with galaxy
observations on small scales, which BEC-CDM may overcome for a large range of
particle mass m and self-interaction strength g. For quantum-coherence on
galactic scales of radius R and mass M, either the de-Broglie wavelength
lambda_deB ~ m_H \cong 10^{-25}(R/100 kpc)^{-1/2}(M/10^{12}
M_solar)^{-1/2} eV, or else lambda_deB << R but self-interaction balances
gravity, requiring m >> m_H and g >> g_H \cong 2 x 10^{-64} (R/100
kpc)(M/10^{12} M_solar)^{-1} eV cm^3. Here we study the largely-neglected
effects of angular momentum. Spin parameters lambda \cong 0.05 are expected
from tidal-torquing by large-scale structure, just as for sCDM. Since lab BECs
develop quantum vortices if rotated rapidly enough, we ask if this angular
momentum is sufficient to form vortices in BEC haloes, affecting their
structure with potentially observable consequences. The minimum angular
momentum for this, L_{QM} = , requires m >= 9.5 m_H for lambda =
0.05, close to the particle mass required to influence structure on galactic
scales. We study the equilibrium of self-gravitating, rotating BEC haloes which
satisfy the Gross-Pitaevskii-Poisson equations, to calculate if and when
vortices are energetically favoured. Vortices form as long as self-interaction
is strong enough, which includes a large part of the range of m and g of
interest for BEC-CDM haloes.Comment: Several typos and numerical typos (incl. in Fig.6, Table 2 and Table
3) have been corrected and references have been updated after proof-reading
stage; MNRAS in press; 29 pages; 11 figure
Midgut pain due to an intussuscepting terminal ileal lipoma: a case report
<p>Abstract</p> <p>Introduction</p> <p>The occurrence of intussusception in adults is rare. The condition is found in 1 in 1300 abdominal operations and 1 in 100 patients operated for intestinal obstruction. The child to adult ratio is 20:1.</p> <p>Case presentation</p> <p>A 52-year-old Irish Caucasian woman was investigated for a 3-month history of intermittent episodes of colicky midgut pain and associated constipation. Ileocolonoscopy revealed a pedunculated lesion in the terminal ileum prolapsing into the caecum. Computed tomography confirmed a smooth-walled, nonobstructing, low density intramural lesion in the terminal ileum with secondary intussusception. A laparoscopic small bowel resection was performed. Histology revealed a large pedunculated polypoidal mass measuring 4 × 2.5 × 2 cm consistent with a submucosal lipoma. She had complete resolution of her symptoms and remained well at 12-month follow-up.</p> <p>Conclusion</p> <p>This case highlights an unusual cause of incomplete small bowel obstruction successfully treated through interdisciplinary cooperation. Ileal lipomas are not typically amenable to endoscopic removal and require resection. This can be successfully achieved via a laparoscopic approach with early restoration of premorbid functioning.</p
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