The sensitivity of heterogeneous energetic (HE) materials (propellants, explosives, and pyrotechnics) is critically dependent on their microstructure. Initiation of chemical reactions occurs at hot ...spots due to energy localization at sites of porosities and other defects. Emerging multi-scale predictive models of HE response to loads account for the physics at the meso-scale, i.e. at the scale of statistically representative clusters of particles and other features in the microstructure. Meso-scale physics is infused in machine-learned closure models informed by resolved meso-scale simulations. Since microstructures are stochastic, ensembles of meso-scale simulations are required to quantify hot spot ignition and growth and to develop models for microstructure-dependent energy deposition rates. We propose utilizing generative adversarial networks (GAN) to spawn ensembles of synthetic heterogeneous energetic material microstructures. The method generates qualitatively and quantitatively realistic microstructures by learning from images of HE microstructures. We show that the proposed GAN method also permits the generation of new morphologies, where the porosity distribution can be controlled and spatially manipulated. Such control paves the way for the design of novel microstructures to engineer HE materials for targeted performance in a materials-by-design framework.
Paraxial ray optics cloaking Choi, Joseph S; Howell, John C
Optics express,
2014-Dec-01, 2014-12-01, 20141201, Letnik:
22, Številka:
24
Journal Article
Recenzirano
Odprti dostop
Despite much interest and progress in optical spatial cloaking, a three-dimensional (3D), transmitting, continuously multidirectional cloak in the visible regime has not yet been demonstrated. Here ...we experimentally demonstrate such a cloak using ray optics, albeit with some edge effects. Our device requires no new materials, uses isotropic off-the-shelf optics, scales easily to cloak arbitrarily large objects, and is as broadband as the choice of optical material, all of which have been challenges for current cloaking schemes. In addition, we provide a concise formalism that quantifies and produces perfect optical cloaks in the small-angle ('paraxial') limit.
The liver is critical for maintaining systemic energy balance during starvation. To understand the role of hepatic fatty acid β-oxidation on this process, we generated mice with a liver-specific ...knockout of carnitine palmitoyltransferase 2 (Cpt2L−/−), an obligate step in mitochondrial long-chain fatty acid β-oxidation. Fasting induced hepatic steatosis and serum dyslipidemia with an absence of circulating ketones, while blood glucose remained normal. Systemic energy homeostasis was largely maintained in fasting Cpt2L−/− mice by adaptations in hepatic and systemic oxidative gene expression mediated in part by Pparα target genes including procatabolic hepatokines Fgf21, Gdf15, and Igfbp1. Feeding a ketogenic diet to Cpt2L−/− mice resulted in severe hepatomegaly, liver damage, and death with a complete absence of adipose triglyceride stores. These data show that hepatic fatty acid oxidation is not required for survival during acute food deprivation but essential for constraining adipocyte lipolysis and regulating systemic catabolism when glucose is limiting.
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•Hepatic fatty acid oxidation (FAO) is critical for liver physiology during starvation•Hepatic FAO suppresses adipose lipolysis and systemic catabolism•Upon fasting, loss of hepatic FAO induces Pparα target genes in the liver•A ketogenic diet induces severe lipolysis and lethality in hepatic FAO-deficient mice
Lee et al. have generated mice that lack mitochondrial long-chain fatty acid β-oxidation specifically in the liver. They report that these mice can survive a 24-hr fast but not a low-carbohydrate ketogenic diet. Surprisingly, whole-body energy expenditure is largely maintained due to increased peripheral catabolism.
To determine the role of fatty acid oxidation on the cellular, molecular, and physiologic response of brown adipose tissue to disparate paradigms of chronic thermogenic stimulation.
Mice with an ...adipose-specific loss of Carnitine Palmitoyltransferase 2 (Cpt2
), that lack mitochondrial long chain fatty acid β-oxidation, were subjected to environmental and pharmacologic interventions known to promote thermogenic programming in adipose tissue.
Chronic administration of β3-adrenergic (CL-316243) or thyroid hormone (GC-1) agonists induced a loss of BAT morphology and UCP1 expression in Cpt2
mice. Fatty acid oxidation was also required for the browning of white adipose tissue (WAT) and the induction of UCP1 in WAT. In contrast, chronic cold (15 °C) stimulation induced UCP1 and thermogenic programming in both control and Cpt2
adipose tissue albeit to a lesser extent in Cpt2
mice. However, thermoneutral housing also induced the loss of UCP1 and BAT morphology in Cpt2
mice. Therefore, adipose fatty acid oxidation is required for both the acute agonist-induced activation of BAT and the maintenance of quiescent BAT. Consistent with this data, Cpt2
BAT exhibited increased macrophage infiltration, inflammation and fibrosis irrespective of BAT activation. Finally, obese Cpt2
mice housed at thermoneutrality exhibited a loss of interscapular BAT and were refractory to β3-adrenergic-induced energy expenditure and weight loss.
Mitochondrial long chain fatty acid β-oxidation is critical for the maintenance of the brown adipocyte phenotype both during times of activation and quiescence.
Inborn errors of immunity are a group of rare genetically determined diseases that impair immune system development or function. Many of these diseases include immune dysregulation, autoimmunity, or ...autoinflammation as prominent clinical features. In some children diagnosed with very early onset inflammatory bowel disease (VEOIBD), monogenic inborn errors of immune dysregulation underlie disease. We report a case of VEOIBD caused by a novel homozygous loss of function mutation in IL10RB. We use cytometry by time-of-flight with a broad panel of antibodies to interrogate the immunophenotype of this patient and detect reduced frequencies of CD4 and CD8 T cells with additional defects in some populations of T helper cells, innate-like T cells, and memory B cells. Finally, we identify the patient's mutation as a founder allele in an isolated indigenous population and estimate the age of this variant by studying the shared ancestral haplotype.
Abstract
Ongoing challenges with reproducible human norovirus cultivable assays necessitate the use of surrogates, such as feline calicivirus (FCV‐F9) and Tulane virus (TV), during inactivation ...studies. Chlorine alternates used as control strategies include aqueous and gaseous ozone. This study aimed at determining the inactivation of FCV‐F9 and TV by a portable ozone‐generating device. FCV‐F9 (∼8 log PFU/mL) or TV (∼6 log PFU/mL) in sterile‐low‐organic matter‐containing‐water was treated for 0–5 min, or in sterile‐water containing newborn calf serum (high‐organic matter/protein) for 0–38 min with ∼1 ppm ozone (pH 7–6). Infectivity was determined from triplicate treatments using plaque assays. FCV‐F9 titers significantly decreased by 6.07 log PFU/mL after 5 min in ozonated low‐organic‐matter‐containing‐water and was non‐detectable (≤2 log PFU/mL) after 36 min treatments in high‐organic‐matter‐containing water (
p
< 0.05). TV titers decreased by 4.18 log PFU/mL after 4 min in ozonated low‐organic‐matter water (non‐detectable after 4.5 min) and were non‐detectable after 22.5 min treatments of high‐organic‐matter‐containing water (
p
< 0.05). Overall, ∼1 ppm aqueous ozone significantly decreased FCV‐F9 by >6 log PFU/mL after 5 min, TV to non‐detectable levels (≤2 log PFU/mL) after 4.5 min and required longer treatments (>32 and >20 min, respectively) for ≥4 log reduction in high‐organic‐matter‐containing water (
p
< 0.05). For ozone treatment of both viruses, the linear and Weibull models were similar for low‐organic‐load water, though the Weibull model was better for the high‐organic load water. Prior filtration or organic load removal is recommended before ozonation for increased viral inactivation with decreased treatment‐time.
Artificial intelligence (AI) is rapidly emerging as a enabling tool for solving complex materials design problems. This paper aims to review recent advances in AI‐driven materials‐by‐design and their ...applications to energetic materials (EM). Trained with data from numerical simulations and/or physical experiments, AI models can assimilate trends and patterns within the design parameter space, identify optimal material designs (micro‐morphologies, combinations of materials in composites, etc.), and point to designs with superior/targeted property and performance metrics. We review approaches focusing on such capabilities with respect to the three main stages of materials‐by‐design, namely representation learning of microstructure morphology (i. e., shape descriptors), structure‐property‐performance (S−P−P) linkage estimation, and optimization/design exploration. We leave out “process” as much work remains to be done to establish the connectivity between process and structure. We provide a perspective view of these methods in terms of their potential, practicality, and efficacy towards the realization of materials‐by‐design. Specifically, methods in the literature are evaluated in terms of their capacity to learn from a small/limited number of data, computational complexity, generalizability/scalability to other material species and operating conditions, interpretability of the model predictions, and the burden of supervision/data annotation. Finally, we suggest a few promising future research directions for EM materials‐by‐design, such as meta‐learning, active learning, Bayesian learning, and semi‐/weakly‐supervised learning, to bridge the gap between machine learning research and EM research.
When two or more parties need to compute a common result while safeguarding their sensitive inputs, they use secure multiparty computation (SMC) techniques such as garbled circuits. The traditional ...enabler of SMC is cryptography, but the significant number of cryptographic operations required results in these techniques being impractical for most real-time, online computations. Trusted execution environments (TEEs) provide hardware-enforced isolation of code and data in use, making them promising candidates for making SMC more tractable. This paper revisits the history of improvements to SMC over the years and considers the possibility of coupling trusted hardware with SMC. This paper also addresses three open challenges: (1) defeating malicious adversaries, (2) mobile-friendly TEE-supported SMC, and (3) a more general coupling of trusted hardware and privacy-preserving computation.
Background
Pleural effusion can be caused by a wide range of benign and malignant conditions. Pleural biopsy and effusion cytology represent two key methods of pathological diagnosis. To compare the ...performance these two methods, a large cohort of matched pleural biopsy and effusion cytology with clinical follow‐up was reviewed.
Methods
Pleural biopsies and effusion cytology specimens over a period of 18 years were retrieved. Cytology specimens collected within 7 days of pleural biopsy were matched. Reports were reviewed, and the cause for pleural effusion was determined by hospital disease coding and clinical data.
Results
Totally, 3026 cases were included. The leading cause of benign effusion was tuberculosis (n = 650). Malignant pleural effusion (MPE) was more common in older females (p < 0.001) and mostly due to lung cancer (n = 959), breast cancer (n = 64), and mesothelioma (n = 48). The inadequate/insufficient (B1/C1) rate of biopsy was higher than cytology (15.6% vs. 0.3%) but the rates for other diagnostic categories were similar. Biopsy and cytology showed a correlation coefficient of 0.315, improving to 0.449 when inadequate/insufficient (B1/C1) cases were excluded. The ROM for benign cytology (C2) was lower than biopsy (B2) (p < 0.001). Compared with biopsy, the diagnostic accuracy was higher in cytology overall and for metastatic carcinomas (p < 0.001) but lower for hematolymphoid malignancies (p = 0.014) and mesotheliomas (p = 0.002).
Conclusions
These results suggest that effusion cytology may be better for confirming benignity and diagnosing carcinomatous MPE. In these cases, pleural biopsy may be withheld to reduce procedural risks. However, for suspected hematolymphoid malignancies and mesothelioma, biopsy should be considered.
Effusion cytology is superior to pleural biopsy in excluding malignant pleural effusion and diagnosis of metastatic carcinomas.
Paraxial full-field cloaking Choi, Joseph S; Howell, John C
Optics express,
2015-Jun-15, 2015-06-15, 20150615, Letnik:
23, Številka:
12
Journal Article
Recenzirano
Odprti dostop
We complete the 'paraxial' (small-angle) ray optics cloaking formalism presented previously Opt. Express 22, 29465 (2014), by extending it to the full-field of light. Omnidirectionality is then the ...only relaxed parameter of what may be considered an ideal, broadband, field cloak. We show that an isotropic plate of uniform thickness, with appropriately designed refractive index and dispersion, can match the phase over the whole visible spectrum. Our results support the fundamental limits on cloaking for broadband vs. omnidirectionality, and provide insights into when anisotropy may be required.
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