Federal Rule of Criminal Procedure 6(e) functionally binds everyone who is present during grand jury proceedings (except witnesses) to secrecy. But questions arise when courts are asked to make ...exceptions to grand jury secrecy outside those enumerated in the rule, such as exceptions for Congress or for the release of historically significant grand jury records.
This Note examines the propriety of judge-made exceptions to grand jury secrecy. Contrary to some courts authorizing disclosure outside of Rule 6(e), this Note argues that the text and development of Rule 6(e), along with limitations on courts' inherent authority over grand jury procedure, caution against this practice. The tension between the current practice of some courts and the apparent meaning of Rule 6(e) renders the law of grand jury secrecy unsettled. To clarify the law, the Advisory Committee on Criminal Rules should add a residual exception to Rule 6(e) that would not only give courts flexibility and discretion but also a clear source of authority on which to authorize disclosures.
Fused filament fabrication (FFF) has seen broad industrial adoption as it is capable of manufaturing large complex parts from robust thermoplastics in a cost‐effective manner. However, the mechanical ...performance of the printed parts is limited due to poor interlayer bonding and the presence of voids. In order to overcome these drawbacks, the addition of short or continuous fibers into the polymer matrix has been investigated, as the fibers can act as a mechanical reinforcement while also mitigating residual stress resulting from the material's rapid solidification following extrusion. Therefore, understanding the implications of process parameters and fiber reinforcements on printed part properties through detailed crystallization analysis and rheological characterizations is of paramount importance. The goal of this study is to understand the process–structure–property relationships of short carbon fiber‐reinforced polyamide 6 (CF‐PA6) by comparing the melt rheology and crystallinity of CF‐PA6 versus a neat PA6 polymer. Differences in the melting and crystallization behavior resulting from the reinforcing fibers revealed an increased time window for crystallization in the fiber‐reinforced matrix. Rheological characterizations at the recommended printing temperatures demonstrate the shear‐thinning behavior of the samples at shear rates relevant to FFF. From a statistical design of experiments analysis, the layer thickness was found to be the most significant parameter affecting the tensile properties of a printed part at a constant printing temperature and printing speed. The tensile fracture surfaces of the printed specimens using scanning electron microscopy were analyzed to provide insights into the failure mechanisms as a function of AM processing variables.
Prior research has demonstrated that fiber-sizings can be designed to yield composite materials that simultaneously possess high energy absorption and structural properties. The improved mechanical ...properties resulted from control of the fiber surface chemistry and nano-scale topological features within the fiber–matrix interphase. The present study further explains the role of sizing chemistry and surface roughness on composite material performance. Model and commercial glass fiber epoxy specimens were fabricated using these fiber sizing systems resulting in interphase regions with varied surface topology and chemical functionality. Micromechanical measurements were performed using the microdroplet adhesion test method to quantify the fiber–matrix interfacial properties. Improvement in energy absorption and interfacial shear strength due to the presence of the nano-scale silica were quantified. Inspection of the failure modes revealed that the existence of colloidal silica promotes crack propagation along a more tortuous path within the interphase that results in progressive failure and contributes to increased energy dissipation.
Electrical phenomena play an important role in numerous biological processes including cellular signaling, early embryogenesis, tissue repair and remodeling, and growth of organisms. Electrical and ...magnetic effects have been studied on a variety of stimulation strategies and cell types regarding cellular functions and disease treatments. In this review, we discuss recent advances in using three different stimulation strategies, namely electrical stimulation via conductive and piezoelectric materials as well as magnetic stimulation via magnetic materials, to modulate cell and tissue properties. These three strategies offer distinct stimulation routes given specific material characteristics. This review will evaluate material properties and biological response for these stimulation strategies with respect to their potential applications in neural and musculoskeletal research.
Electrospinning is a process by which sub-micron polymer fibers can be produced using an electrostatically driven jet of polymer solution (or polymer melt). Electrospun textiles are of interest in a ...wide variety of applications including semi-permeable membranes, filters, composite applications, and as scaffolding for tissue engineering. The goal of the research presented here is to demonstrate that it is possible to produce sub-micron fibers with a specific surface chemistry through electrospinning. This has been accomplished by electrospinning a series of random copolymers of PMMA-
r-TAN from a mixed solvent of toluene and dimethyl formamide. X-ray Photoelectron Spectroscopy (XPS) analysis shows that the atomic percentage of fluorine in the near surface region of the electrospun fibers is about double the atomic percentage of fluorine found in a bulk sample of the random copolymer, as determined by elemental analysis. These results are in good agreement with XPS and water contact angle results obtained from thin films of the same copolymer materials.
This review documents the current state of the art of highly filled (HF) polymer composite systems used in additive manufacturing (AM), with a core focus on short and continuous fiber filled ...composites for use in material extrusion (MatEx) AM. Current state of the art composite materials systems have been succesfully incorporated into the MatEx process with loading percentages up to approximately 45 vol. %. Further increasing the loading percentage would afford significant mechanical improvements that could enable structural performance, however there are currently a number of limitations that need to be addressed. Viscosity limitations associated with MatEx processing of HF composites originate from the low processing pressure inherent to filament feed MatEx processes. Restrictive hot end nozzle geometries (high volume contractions) increase required processing pressure and potential for nozzle clogging failures. The increased viscosity of the HF composite reduces interlayer contact and adhesion during the printing process, resulting in increased void spacing. Mechanical limitations of HF composites processed using MatEx are also reviewed. Flow induced fiber orientation and its influence on viscosity and mechanical anisotropy are investigated. Fiber breakage as well as strain to break limitations are reviewed. Lastly, the geometric packing limitations of fibers within a circular bound nozzle are reviewed. This review takes an in-depth look at recent advances in addressing these challenges, and discusses opportunities for realizing MatEx processing of HF composite systems with significantly improved performance.
Objective:
The purpose of this review is to evaluate the efficacy and safety of colchicine after acute coronary syndrome (ACS).
Data Sources:
English-language searches were made of MEDLINE and EMBASE ...from database inception through mid-June 2020.
Study Selection and Data Extraction:
Randomized trials characterizing the effects of colchicine in ACS were considered. Of 627 title and abstracts identified, nine trials were included. Two reviewers extracted data and rated study quality.
Data Synthesis:
Four studies showed colchicine did not attenuate C-reactive protein production. Colchicine did modulate the NOD-like receptor family pyrin domain containing 3 inflammasome in 3 studies and reduced production of chemokine ligand 2 (CCL2), CCL5, and C-X3-C motif chemokine ligand 1 in 1 study. Major adverse cardiovascular events (MACE) were not significantly different at 30 days in 3 studies, administered as 1.8 mg preprocedurally or scheduled 1 mg daily. One study found a significant reduction in MACE with colchicine 0.5 mg daily over median 22.6 months (hazard ratio = 0.77; 95% CI = 0.61-0.96). Colchicine is associated with increased gastrointestinal adverse events but was generally well tolerated.
Relevance to Patient Care and Clinical Practice:
Colchicine is likely to reduce MACE in an ACS population if administered for greater than 30 days but does not improve MACE when administered only preprocedurally.
Conclusions:
Adjunctive colchicine 0.5 mg daily for greater than 30 days is reasonable for an ACS population on guideline-directed medical therapy treated with PCI. Additional studies are needed to validate and determine the durability of these benefits.
Achieving high impact energy absorption without loss of structural performance in a glass fiber-reinforced composite can be obtained through a “materials by design” approach of the fiber matrix ...interphase through modification of current commercially formulated silane-based fiber sizing packages. In this paper, we document our attempt to balance the structural and impact performance of glass-reinforced composites produced using a fiber-sizing package composed of mixed silane coupling agents to vary the reactivity of the fiber with the matrix phase. Additionally, enhancement of post-failure energy absorption through increased frictional dissipation during fiber–matrix pull-out was explored through control of the surface roughness of the glass fibers. A unique inorganic–organic hybrid fiber sizing formulation was successfully applied at a commercial E-glass manufacturing facility to produce rovings as well as woven fabric reinforcements. Composite materials were manufactured using these specialized fabrics and the preliminary structural and impact energy responses of these materials have been measured.
Tobacco (Nicotiana tabacum) is cultivated in more than 100 countries, and in 2004, some 5.73 million metric tons dry weight of tobacco were grown worldwide. The top five tobacco producers forecast ...for 2004 are China (2.01 million metric tons; 35.1%), Brazil (757 thousand metric tons; 13.2%), India (598 thousand metric tons; 10.4%), United States (358 thousand metric tons; 6.2%), and Malawi (138 thousand metric tons; 2.4%). Together, these five countries account for two-thirds of worldwide tobacco production. Tobacco farming presents several hazards to those who cultivate and harvest the plant. Although some of these hazards, such as pesticide exposure and musculoskeletal trauma, are faced by workers in other types of agricultural production, tobacco production presents some unique hazards, most notably acute nicotine poisoning, a condition also known as green tobacco sickness (GTS). GTS is an occupational poisoning that can affect workers who cultivate and harvest tobacco. It occurs when workers absorb nicotine through the skin as they come into contact with leaves of the mature tobacco plant. GTS is characterized largely by nausea, vomiting, headache, muscle weakness, and dizziness. Historically, children have played a role in agricultural production in the United States, and they continue to do so today. This includes tobacco farming. The North American Guidelines for Children's Agricultural Tasks, a set of injury prevention guidelines prepared by the National Children's Center for Rural and Agricultural Health and Safety, lists GTS as one of several hazards children face when working on tobacco farms. Children 17 years of age and younger who work on U.S. tobacco farms come from three main groups: members of farm families, migrant youth laborers (primarily Latinos), and other hired local children. All three groups are at risk for GTS. Beyond the U.S., tobacco production using child labor is an emerging topic of concern in developing nations. An international movement, advocated by the Eliminating Child Labor in Tobacco Foundation, is underway to restrict child labor in tobacco production. GTS is a unique occupational poisoning associated with tobacco farming. We suspect that many public health practitioners, clinicians, advocates, and researchers are unaware of GTS among children and adolescents. In this article, we provide an overview of GTS among young people who work in tobacco, summarize reports documenting pediatric GTS cases, explain GTS etiology, and present three case studies of pediatric GTS in Kentucky. In addition, we discuss the need for expanded surveillance and prevention of GTS, both in the United States and globally.
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