Scattering of underwater sound from a porous solid sphere

An experiment was performed to measure the scattering of underwater sound from a porous solid for the first time. Two porous solid spheres somposed of heat-epoxied glass beads of 100 and 500 micron mean bead diameter were used. The permeability, porosity, and shear modulus of each sample were estimated from measurements made on cylindrical samples which had been manufactured at the same time and of the same glass beads as the spheres. These material poperties were used as input to a theoretical model for the sound scattered from a poro-elastic sphere imbedded in a poro-elastic host developed by Kargl and Lim. The experimental data were compared to the theoretical calculations. Theoretical calculations with 0%, 3%, and 10% skeletal fram damping were compared to experimental data. Very good agreement between measured and predicted scattering was obtained for each sample over certain frequency ranges, taking 10% fram damping in the calculations. For other frequency ranges the agreement was less than good. No systematic trend in the agreement could be discerned with regard to prous grain size or sound frequencyhttp://archive.org/details/scatteringofunde00huskLieutenant, United States NavyApproved for public release; distribution is unlimited

Food Insecurity and Metabolic Control Among U.S. Adults With Diabetes

OBJECTIVE We sought to determine whether food insecurity is associated with worse glycemic, cholesterol, and blood pressure control in adults with diabetes. RESEARCH DESIGN AND METHODS We conducted a cross-sectional analysis of data from participants of the 1999–2008 National Health and Nutrition Examination Survey. All adults with diabetes (type 1 or type 2) by self-report or diabetes medication use were included. Food insecurity was measured by the Adult Food Security Survey Module. The outcomes of interest were proportion of patients with HbA1c >9.0% (75 mmol/mol), LDL cholesterol >100 mg/dL, and systolic blood pressure >140 mmHg or diastolic blood pressure >90 mmHg. We used multivariable logistic regression for analysis. RESULTS Among the 2,557 adults with diabetes in our sample, a higher proportion of those with food insecurity (27.0 vs. 13.3%, P 9.0% (75 mmol/mol). After adjustment for age, sex, educational attainment, household income, insurance status and type, smoking status, BMI, duration of diabetes, diabetes medication use and type, and presence of a usual source of care, food insecurity remained significantly associated with poor glycemic control (odds ratio [OR] 1.53 [95% CI 1.07–2.19]). Food insecurity was also associated with poor LDL control before (68.8 vs. 49.8, P = 0.002) and after (1.86 [1.01–3.44]) adjustment. Food insecurity was not associated with blood pressure control. CONCLUSIONS Food insecurity is significantly associated with poor metabolic control in adults with diabetes. Interventions that address food security as well as clinical factors may be needed to successfully manage chronic disease in vulnerable adults

MYC pathway activation in triple-negative breast cancer is synthetic lethal with CDK inhibition

Estrogen, progesterone, and HER2 receptor-negative triple-negative breast cancers encompass the most clinically challenging subtype for which targeted therapeutics are lacking. We find that triple-negative tumors exhibit elevated MYC expression, as well as altered expression of MYC regulatory genes, resulting in increased activity of the MYC pathway. In primary breast tumors, MYC signaling did not predict response to neoadjuvant chemotherapy but was associated with poor prognosis. We exploit the increased MYC expression found in triple-negative breast cancers by using a synthetic-lethal approach dependent on cyclin-dependent kinase (CDK) inhibition. CDK inhibition effectively induced tumor regression in triple-negative tumor xenografts. The proapoptotic BCL-2 family member BIM is up-regulated after CDK inhibition and contributes to this synthetic-lethal mechanism. These results indicate that aggressive breast tumors with elevated MYC are uniquely sensitive to CDK inhibitors

The Gly2019Ser mutation in LRRK2 is not fully penetrant in familial Parkinson's disease: the GenePD study

<p>Abstract</p> <p>Background</p> <p>We report age-dependent penetrance estimates for leucine-rich repeat kinase 2 (<it>LRRK2</it>)-related Parkinson's disease (PD) in a large sample of familial PD. The most frequently seen <it>LRRK2 </it>mutation, Gly2019Ser (G2019S), is associated with approximately 5 to 6% of familial PD cases and 1 to 2% of idiopathic cases, making it the most common known genetic cause of PD. Studies of the penetrance of <it>LRRK2 </it>mutations have produced a wide range of estimates, possibly due to differences in study design and recruitment, including in particular differences between samples of familial PD versus sporadic PD.</p> <p>Methods</p> <p>A sample, including 903 affected and 58 unaffected members from 509 families ascertained for having two or more PD-affected members, 126 randomly ascertained PD patients and 197 controls, was screened for five different <it>LRRK2 </it>mutations. Penetrance was estimated in families of <it>LRRK2 </it>carriers with consideration of the inherent bias towards increased penetrance in a familial sample.</p> <p>Results</p> <p>Thirty-one out of 509 families with multiple cases of PD (6.1%) were found to have 58 <it>LRRK2 </it>mutation carriers (6.4%). Twenty-nine of the 31 families had G2019S mutations while two had R1441C mutations. No mutations were identified among controls or unaffected relatives of PD cases. Nine PD-affected relatives of G2019S carriers did not carry the <it>LRRK2 </it>mutation themselves. At the maximum observed age range of 90 to 94 years, the unbiased estimated penetrance was 67% for G2019S families, compared with a baseline PD risk of 17% seen in the non-<it>LRRK2</it>-related PD families.</p> <p>Conclusion</p> <p>Lifetime penetrance of <it>LRRK2 </it>estimated in the unascertained relatives of multiplex PD families is greater than that reported in studies of sporadically ascertained <it>LRRK2 </it>cases, suggesting that inherited susceptibility factors may modify the penetrance of <it>LRRK2 </it>mutations. In addition, the presence of nine PD phenocopies in the <it>LRRK2 </it>families suggests that these susceptibility factors may also increase the risk of non-<it>LRRK2</it>-related PD. No differences in penetrance were found between men and women, suggesting that the factors that influence penetrance for <it>LRRK2 </it>carriers are independent of the factors which increase PD prevalence in men.</p

Intrinsic Reward Motivates Large-Scale Shifts Between Cognitive Control and Default Mode Networks During Task Performance

Cognitive control is an important framework for understanding the neuropsychological processes that underlie and enable the successful completion of everyday tasks. Only recently has research in this area investigated motivational contributions to control allocation. An important gap in our understanding is the way in which intrinsic rewards associated with a task motivate the sustained allocation of cognitive control. In three behavioral and one functional magnetic resonance imaging studies, we use a naturalistic and open-sourced simulator to show that changes in the balance between task difficulty and an individual’s ability to perform the task result in different levels of intrinsic reward, which motivates dynamic shifts between networked brain states. Specifically, high levels of intrinsic reward associated with a balance between task difficulty and individual ability are associated with increased connectivity between cognitive control and reward networks. By comparison, a mismatch between task difficulty and individual ability is associated with lower levels of intrinsic reward and corresponds to increased activity within the default mode network. Insular activation suggests that motivational salience, as defined by the level of intrinsic reward, drives shifts between networked brain states associated with task engagement or disengagement. These results implicate reward processing as a critical component of cognitive control

Impacts and consequences of non-standard cots C4I system acquisition upon associated programs of record

field capabilities quickly enough to meet warfighter requirements. DoD acquisition can not keep pace with the rate of C4I technology growth and is encumbered by layers of procedural bureaucracy. Subsequently existing Programs of Record were harmed by the resulting non-standard acquisitions. More reform is neither necessary nor the panacea. Adequate processes and programs exist to expedite the fielding of new capabilities. Optimization of existing processes and programs combined with greater warfighter involvement are necessary to prevent future occurrences of non-standard acquisition. Adherence to existing rules and regulations when combined with reduction of bureaucracy will reduce future occurrences of non-standard COTS C4I equipment acquisition and speed the fielding of new capabilities.http://archive.org/details/impactsndconsequ109453288Science Applications International Corporation author (civilian).Approved for public release; distribution is unlimited