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Can volatile organic compounds (VOC) be modelled in an IVF clinical setting?The study performed equilibrium modelling of low concentrations of airborne VOC partitioning from the air phase into the oil cover layer into the water-based culture media and into/onto the embryo (air-oil-water-embryo). The air-phase VOC were modelled based on reported VOC concentrations found in modern assisted reproductive technology (ART) suites, older IVF clinics, and hospitals, as well as at 10 parts per billion (ppb) and 100 ppb for all compounds. The modelling was performed with 23 documented healthcare-specific VOC.Based on the partitioning model, seven compounds (acrolein, formaldehyde, phenol, toluene, acetaldehyde, ethanol and isopropanol) should be of great concern to the embryologist and clinician. Acrolein, formaldehyde, phenol, toluene and acetaldehyde are the VOC with the most potent cytotoxic factor and the highest toxic VOC concentration in media. In addition, ethanol and isopropanol are routinely found in the greatest air-phase concentrations and modelled to have the highest water-based culture concentrations.The results of the equilibrium partitioning modelling of VOC provides a fundamental understanding of how airborne VOC partition from the air phase and negatively influence human IVF outcomes. The results presented here are based on the theoretical model and the values presented have not yet been measured in a laboratory or clinical setting. High air-phase concentrations and toxic concentrations of VOC in culture media are likely indicators of poor clinical outcomes. Based on this model, improved air quality in IVF laboratories reduces the chemical burden imparted on embryos, which supports findings of improved IVF outcomes with reduced air-phase VOC concentrations.

Diesel particulate filters (DPFs) are porous ceramic wall-flow devices utilized in diesel exhaust systems to capture particulate matter. DPFs require intermittent on-board regeneration to combust the soot component of particulate matter in order to lower engine back pressure. In addition, proper DPF maintenance requires removal from the vehicle every 100,000–200,000 miles for off-board cleaning to remove the accumulated inorganic ash component of particulate matter. In this study, the capability to quantify off-board DPF cleaning effectiveness was assessed by measuring particulate removal effectiveness and back pressure relief. DPFs were selected from vehicles with the same DPF manufacturer so as to eliminate DPF sizing as a variable. A total of 34 DPFs were removed from on-road heavy-duty diesel vehicles with mostly highway miles with low idle time and were cleaned using pneumatic air cleaning, thermal calcination, and wet cleaning processes. The cleaning processes were used alone, and in series. DPF cleaning effectiveness was evaluated by quantifying particulate removal by weight loss and by measuring DPF back pressure both before and after each process step. The estimated ash exposure values for DPFs in the study were compared with total particulate matter removed from cleaning. The results indicate that back pressure does not provide a complete quantification for off-board cleaning effectiveness, as back pressure may be decreased while DPFs may still retain significant levels of ash.

Recent advances in additive manufacturing technologies for cementitious construction have mainly focused on low resolution fused deposition methods, herein the authors aim to advance high resolution binder jet printing methods. The inherent challenge of additive binder jet cement-based printing is to achieve adequate mechanical strengths and maintain geometry without the agitation and casting of conventional fabrication. The authors utilize a commercially available binder jet printer to fabricate sample specimens that are used to assess material and geometric properties. A novel water-based binder formulation, compatible with concrete chemistry and piezoelectric jetting, is developed. This study examines a dry cementitious mix comprised of round grain fine aggregates and calcium sulfoaluminate (CSA) cement. The printed samples have a density of 1474–1501 kg/m3, 28-day compressive strengths of 5.94–6.70 MPa, and flexural strengths of 1.76–2.39 MPa. The results indicate that binder jet printed CSA cement with the addition of fine aggregates possess the strength and the resolution to produce high detail objects with rapid production capability and compatibility in applications with conventional construction materials.

Renewable fuels are necessary energy sources as bio-based combustible fuels can be utilized in existing infrastructure while lowering the dependence on petrochemical based fuels. Current bio-fuels are predominantly crop-based which require tillable land, fertilizer, chemicals, irrigation, and fuel to cultivate the biomass feedstock. This study investigated the hydrothermal conversion of underutilized waste streams for biomass feedstock. This work blended municipal sewage sludge solids, poultry dissolved air flotation solids, and used cooking oil to form a waste slurry that was thermally converted to renewable fuel products. Blended waste processing provides flexibility and robustness in the future of bio-based fuels, and the authors believe this is the first documented hydrothermal processing of this specific blended waste. The waste slurry was heated under subcritical hydrothermal conditions, where solids were separated, and then heated in a second pressurized reaction to complete the thermal conversion process of wastes to recoverable products. Prior to processing, the blended waste slurry contained 8,490 kJ/kg (3,650 BTU/lb). Following processing, the recovered gas products contained 38,747 kJ/kg (16,658 BTU/lb) and 42% methane. The recovered renewable oil contained 40,468 kJ/kg (17,398 BTU/lb) and 0.012% ash. The effluent produced water was appraised for nutrient content and was found to contain 1,689 mg/L of nitrogen, which has potential as a liquid fertilizer product. The produced gas fuel, produced liquid fuel, solid char, and produced nutrient laden water were determined to be potential marketable products.

In an effort to develop highly porous silicon carbide for high temperature air filtration, an alternative approach to forming silicon carbide nanowires (SCNW) was developed by blending carbon containing materials with silicon powder and heating these precursors to 1400 °C. The mixing ratio of precursor materials and processing temperature were investigated with respect to the formation of SCNWs. Results indicate that anthracite and starchy materials can yield high purity SiC ceramics, yet these combinations did not produce SiC nanowires. SCNWs were successfully grown from a combination of guar gum and silicon powder precursors at 1400 °C, when held for 4 h with an argon flow rate of 1 L/min. The produced SiC is a high purity product with nanowire diameters of approximately 40 nm and ranging in length from about 100 nm to several micrometers in length. Iron was used to catalyze the nanowire growth through vapor-liquid-solid (VLS) mechanisms by adsorbing the silicon and carbon vapor at the iron rich tip, which then led the nanowire growth. TEM analysis revealed the growth of SCNWs followed the [1,1,2] direction. A wafer comprised of the synthesized SiC nanowire matrix has much higher hardness compared with a wafer of the porous commercially available cordierite.

A simple method to modify hydroxyapatite and pectin into an efficient zinc sorbent was investigated. Process and formulation modifications enabled the formation of a flower-like hydroxyapatite/pectin hybrid material. The hybrid material was characterized with scanning electron microscopy, elemental analysis, and zeta potential tests. Sorption data were analyzed with different kinetic and isotherm models. The results showed that the pseudo-second order kinetic model and two-staged isotherm curves with Langmuir at the first stage and a Freundlich model the at second stage could best describe the zinc sorption on the hybrid. The maximum experimental sorption capacity was 330.4 mg Zn2+ per gram of sorbent, which was obtained with an initial concentration of 260 mg L−1 Zn2+ at pH 5.0. pH monitoring and Zeta potential tests suggested surface complexation and electrostatic attraction were fundamental in the zinc sorption process.

The fundamentals of silicic acid sorption on customized metal organic frameworks (MOFs) synthesized with green chemistry was investigated. The authors appraised the influence of pH, contact time, initial concentration of silicic acid as SiO2 on the sorption effectiveness. In-situ Raman tests confirm that hydroxyl group was involved in the silicic acid sorption process. Batch tests demonstrate that the pseudo-second order kinetic model and Freundlich isotherm model best describe the silicic acid sorption on the MOF-Al while the pseudo-second order kinetic model and Langmuir isotherm model can best describe the sorption on the MOF-Fe and MOF-Cu. The maximum experimental silicic acid sorption capacity was 182.2 mg SiO2/g for MOF-Al, 157.7 mg SiO2/g for MOF-Fe and 201.4 mg SiO2/g for MOF-Cu. The MOF-Fe and MOF-Cu are the most promising variation as they represent the most robust materials tested.

The surfaces of most materials in aqueous systems are charged due to the ionization of surface functional groups. When these surfaces interact, the surface charge, electrostatic potential, and pH will vary as a function of separation distance, and this process is termed the charge-regulation effect. Charge regulation is a controlling factor in the adhesion and transport of colloids and microorganisms in aqueous systems, and its modeling requires representation of the pH–charge response of the surfaces, typically provided as the equilibrium constants (K) and site densities (N) of the dominant surface functional groups. Existing methods for obtaining these parameters demonstrate shortcomings when applied to many natural and man-made materials, such as weathered materials, materials with undefined or complex surface structures, and permeable materials, and for materials that do not provide the requisite high surface area in suspension due to small sample sizes. This hinders inclusion of the charge-regulation...

A 1.02pJ/b USR link carrying 416.67 Gb/s/mm die edge (500Gb/s aggregated data rate) in 16nm FinFET, while occupying 2.4mm2, is presented. To enable dense routing over conventional package material, a modified correlated NRZ signaling with low sensitivity to ISI, Xtalk, and common-mod noise has been developed. A matched CTLE/slicer topology has been employed to enhance robustness of the receiver over PVT. A very wideband Rx PLL tracks the majority of Tx jitter, resulting in significant power saving by relaxing Tx design constraints.

The effects of Na, K, and Fe with porous cordierite were investigated at elevated temperatures. Samples of unused diesel particulate filter cordierite substrates were doped with sodium, potassium, and iron. The doped samples were heated in a thermal gravimetric analyzer to 300, 500, 900, and 1100 °C. The resulting interactions were analyzed with scanning electron microscopy, wavelength-dispersive X-ray spectroscopy (WDS), and X-ray diffraction. The alkalis and iron induced corrosion and degradation to the cordierite substrate at temperatures lower than pristine cordierite substrate samples. The corrosion and degradation pathway followed the porous structure as observed with WDS.

Diesel particulate filters (DPFs) are essential particulate matter emission control devices. Some diesel particulate filters have been observed to fail during industrial-fleet vehicle use. DPFs that fail during vehicle use compromise particulate matter emission capture. Herein, failures in cordierite DPF substrates observed during commercial fleet use were characterized as pinhole failure, melt failure, crack failure, and fouling failure. The observed failures were correlated to particulate matter chemical composition and physical changes in the cordierite substrate of the exhausted DPFs. The physical-chemical characteristics of pinhole failure, melt failure, crack failure, and fouling failure were determined by applying scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). Results indicate that the chemical composition and crystalline structures of cordierite DPF substrate changed according to the failure characterization. The specific changes to the cordierite substrate during failure can contribute towards understanding fundamental DPF failure mechanisms.

Delivering effective, efficient and extraordinary healthcare to all requires full access to care. Health insurance, either private or government, is essential to that access, which is why Beaumont Health is urging President Donald Trump and members of Congress to tread carefully as they consider changes in the Affordable Care Act.

Activated carbon adsorption experiments were carried out with humic acid solutions to determine adsorption isotherms and kinetics. Four commercial coconut shell–based activated carbons were...

When comparing a novel collagen and alkali silicate core binder system to a conventional phenolic urethane binder system during full-scale trials, the phenolic urethane incurred a 33.3 % higher emissions rate than did the novel binder system. This was chronicled during several hours of stack tests in a full-scale trial demonstration of 3500 novel cores at a high-volume automotive ductile iron foundry. Baseline phenolic urethane emissions were determined immediately prior to running the collagen and alkali silicate cores, when making an identical casting. Approximately 10 % of the demonstration iron castings were inspected for defects, of which none (0 %) were scrapped on account of core-related defects. Also, the novel core’s shakeout was complete. These favorable results were achieved with humidity-free storage of the cores over the 10 days that the cores were made. These novel demonstration cores required somewhat longer curing time in the core-making machine, than did conventional phenolic urethane cores; and this curing rate was influenced by air flow and pressure into the core box. Also, tensile specimen tests of the collagen and alkali silicate-adhered system were higher than that of the conventional phenolic urethane system. When exposed to high humidity levels (80–95 % relative humidity) for prolonged periods of time (10 days), the collagen and alkali silicate-adhered tensile specimens degraded in terms of tensile strength and scratch hardness. These losses mostly rebounded when the tensile specimens were re-dried.

A novel core binder system has been devised that is comprised of hydrolyzed collagen and alkali silicates. Cores that employ this hybrid binder were tested in a full-scale demonstration at a partner foundry. Among the 244 iron castings manufactured at this facility while using these hybrid binders, none of the iron castings were rejected as scrap due to core-related defects. The core regions of these iron castings exhibited no deformation, veining, or erosion from molten iron exposure. Moreover, these hybrid silicate-collagen cores demonstrated satisfactory shakeout during full-scale demonstrations. This hydrolyzed collagen-alkali silicate binder yielded cores that achieved a higher tensile strength and less hot distortion than conventional phenolic urethane binders.

Background ST-segment elevation in lead aVR predicts left main and/or three-vessel disease (LM/3VD) in patients with acute coronary syndromes. ST-segment elevation in lead aVR is generally reciprocal to and accompanied by ST-segment depression in precordial leads. Previous studies have assessed the independent predictive value of ST-segment elevation in lead aVR for LM/3VD in non–ST-segment elevation acute coronary syndrome and have reported conflicting results. Methods We performed a retrospective analysis of 379 patients with non–ST-segment elevation myocardial infarction (NSTEMI). Electrocardiograms on presentation were reviewed especially for ST-segment elevation ≥0.05 mV in lead aVR and ST-segment depression ≥0.05 mV in more than two contiguous leads in any other leads. Results Among 379 patients, 97 (26%) patients had ST-segment elevation in lead aVR and 88 (23%) patients had LM/3VD. Patients with ST-segment elevation in lead aVR had a higher rate of LM/3VD (39% vs. 18%; P < 0.001) and in-hospital revascularization (73% vs. 60%; P = 0.02) driven by a higher rate of in-hospital coronary artery bypass grafting (19% vs. 7%; P < 0.001) than those without ST-segment elevation in lead aVR. On multivariate analysis, ST-segment elevation in lead aVR (odds ratio [OR] 2.05; 95% confidence interval [CI] 1.10–3.77; P = 0.02) and ST-segment depression in leads V1–V4 (OR 2.99; 95% CI 1.46–6.15; P = 0.003) were independent predictors of LM/3VD. Conclusion This study demonstrates that ST-segment elevation in lead aVR is an independent predictor of LM/3VD in patients with NSTEMI.

The use of carbon soot recovered from diesel particulate filters (DPF) has been investigated as a potential adsorbent for heavy metals including cadmium, chromium, and copper from wastewater. Results were compared with the adsorption performance of powder activated carbon (PAC). The uptake capacity of heavy metals for soot was found to be higher than PAC. And the thermodynamic study result for both soot and PAC indicated the adsorption procedures are exothermic. The adsorption studies were carried out for both single and binary systems. The data are best modeled by the monolayer model and Langmuir isotherm model for single systems. The adsorption mechanisms are more complex for binary systems. The kinetic studies indicated the adsorption happens rapidly within the first 1 h, and the results can be best modeled by pseudo-second-order model. The SEM-EDS analysis revealed the soot possesses higher porosity and surface area. Carboxylic and hydroxyl functional groups are the predominant surface functional group on both soot and PAC as revealed by FTIR and IEP values. The adsorption can be explained by both Van Der Waals force and electrostatic force. Graphical abstract ᅟ.

An experimental study was conducted to assess the chloride migration resistance of concrete used for bridge superstructure and substructure projects in the state of Pennsylvania. A total of 68 concrete mixes were sampled and tested to determine the chloride migration coefficient using NT Build 492. A subset of these samples was also examined using the rapid chloride migration and surface resistivity tests. The tested samples exhibit a wide variation in aggregate rock type, cementitious materials and mix proportions. The results show that the concrete migration coefficient varied from 0.54 × 10−12 m2/s for a concrete with 59.4% cement type I, 35% slag and 5.5% silica fume to 30.62 × 10−12 m2/s for a concrete with 100% cement type I, the average migration for all samples was 9.51 × 10−12 m2/s. A statistical analysis shows correlation between migration coefficient, compressive strength, and water/cement ratio but no correlation with aggregate absorption, air entrainment, or aggregate type. The results were utilized to evaluate the life-cycle performance of bridge decks constructed for the Pennsylvania Department of Transportation. Reliability analyses were carried out, where the limit state consisted in the chloride content in concrete at the depth of the reinforcement reaching the critical chloride content for the reinforcing steel corrosion initiation. The chloride diffusion over time was modeled with a probabilistic implementation of Fick’s 2nd law and the evolution of reliability was assessed. The impact of the chloride migration on the expected service life of superstructure components shows that 75% of tested concrete when used with uncoated reinforcement has a 10% likelihood of corrosion initiation within 15 years. This service life is extended to 30 years when epoxy coated reinforcement is used.

The authors and collaborators have devised innovative technologies that decrease foundry costs, pollution, materials use, and energy. These include: (a) applying advanced oxidation to green sand and baghouse dust to diminish clay, coal, sand, volatile organic compounds (VOCs), and costs; (b) replacing phenolic urethane core binders with collagen-alkali silicate binders to diminish VOCs; (c) replacing coke with anthracite fines held together with biomaterial to reduce energy and costs. It is proposed by the authors that if a foundry were to concurrently employ all these innovative technologies (with 50% anthracite bricks), it could potentially diminish overall costs by 6.6%, life cycle energy costs by 15%, VOC pollution by 57%, sand by 85%, clay and coal by 50%, and iron scrap by 9%. These computations are per full-scale operations for advanced oxidation; and R&D results for replacing binders and coke. This paper also notes that when electricity comes primarily from coal fired power plants, electric induction furnaces consumes more life cycle energy than do cupolas for melting iron.

Metalcasting within the United States aims to meet ever-more stringent environmental standards as new process technologies are developed. Conventional foundry core binders are responsible for up to 70% of a foundry's volatile organic compound (VOC) emissions. New core binder technologies are essential for environmental sustainability within foundries. Herein, conventional and novel foundry core binders were appraised using thermal gravimetric analysis (TGA), dynamic mechanical analysis (DMA), hot distortion testing (HDT), and (Pilot-scale) molten iron erosion tests. Inherently, these tests cannot replace full-scale casting trials to evaluate binder effectiveness, however, these tests were performed to more fully elucidate binder properties that might cause casting defects or other unwanted behaviors at high temperatures. During each of these lab protocols, the combination of collagen plus alkali silicate as binders exhibited properties that matched or exceeded those of conventional phenolic urethane. Also, in iron erosion testing, the collagen/alkali silicate binder exhibited the same low erosion as conventional phenolic urethane. In hot distortion testing, the collagen–alkali silicate binder exhibited longer resistance to thermal bending, and comparable thermal flexibility to conventional phenolic urethane.

Silicon carbide nanowires (SCNWs) were grown from anthracite fine surfaces through a simple one-step carbothermal process with silicon powder as the Si precursor. This straightforward and fast formation of SCNWs made it possible to maintain the binding of briquetted waste anthracite fines at very high temperatures as an alternative fuel in foundry cupola furnaces. This SCNW mechanism could thus provide the crucial hot crushing strength in the cupola heat zone and melt zone. Progressive thermal tests exhibited that the formation of the SCNWs started from 1100 C, and was favored at 1400 C. No extra metal catalyst was needed for the growth of the SCNWs. Characterizations were performed by XRD, SEM, EDS, TEM, and SAED. The SCNWs were 30–60 nm in diameter and were typically grown by stacking the (1 1 1) lattice plane of 3C-SiC along the [1 1 1] direction. Many non-epitaxial branches of the nanowires were also formed through this one-step process as observed by TEM. The results suggest that the SCNWs were most likely grown through the vapor–solid mechanism.

David Stephens and colleagues describe their experience of treating patients with Ebola virus disease at Emory University in the United States.

BACKGROUND: ST‐segment elevation in lead aVR predicts left main and/or three‐vessel disease (LM/3VD) in patients with acute coronary syndromes. ST‐segment elevation in lead aVR is generally reciprocal to and accompanied by ST‐segment depression in precordial leads. Previous studies have assessed the independent predictive value of ST‐segment elevation in lead aVR for LM/3VD in non–ST‐segment elevation acute coronary syndrome and have reported conflicting results. METHODS: We performed a retrospective analysis of 379 patients with non–ST‐segment elevation myocardial infarction (NSTEMI). Electrocardiograms on presentation were reviewed especially for ST‐segment elevation ≥0.05 mV in lead aVR and ST‐segment depression ≥0.05 mV in more than two contiguous leads in any other leads. RESULTS: Among 379 patients, 97 (26%) patients had ST‐segment elevation in lead aVR and 88 (23%) patients had LM/3VD. Patients with ST‐segment elevation in lead aVR had a higher rate of LM/3VD (39% vs. 18%; P < 0.001) and in‐hospital revascularization (73% vs. 60%; P = 0.02) driven by a higher rate of in‐hospital coronary artery bypass grafting (19% vs. 7%; P < 0.001) than those without ST‐segment elevation in lead aVR. On multivariate analysis, ST‐segment elevation in lead aVR (odds ratio [OR] 2.05; 95% confidence interval [CI] 1.10–3.77; P = 0.02) and ST‐segment depression in leads V(1)–V(4) (OR 2.99; 95% CI 1.46–6.15; P = 0.003) were independent predictors of LM/3VD. CONCLUSION: This study demonstrates that ST‐segment elevation in lead aVR is an independent predictor of LM/3VD in patients with NSTEMI.

Portions of the greater metropolitan District of Columbia area have water distribution system corrosion problems. This has resulted in elevated levels of heavy metals, in particular lead from some plumbing and service connections. One alternative being considered for corrosion control is the addition of either phosphoric acid (ortho-phosphate) or zinc ortho-phosphate based products at the water treatment plant to inhibit corrosion of plumbing and service connections that contain lead (Cadmus, 2004). A potential consequence of the addition of zinc orthophosphate (ZnOP) to the water supply is the impact of Zn on the operation of the wastewater treatment plants that receive and treat sanitary wastewater from treated water supplies. The objective of this study was to evaluate the impact of ZnOP, and specifically Zn 2+ , on the nitrification process at the Arlington County, Virginia Water Pollution Control Plant (WPCP). Inhibition was investigated using continuous respirometry and nitrate generation rate measurements at the Zn concentration increment expected in the influent wastewater (0.3-0.5 mg/L) as a result of corrosion inhibitor use, although much higher levels of Zn were also evaluated. Short-term batch experiments up to 5 days in length were conducted with fresh mixed liquor samples in an attempt to make 0.5 mg/L Zn as inhibitory as possible, providing conditions that would be expected to sensitize the biomass to Zn stress. Results suggest no significant inhibition at 0.5 mg/L Zn, slight inhibition at 1.0 mg/L Zn after roughly 5-10 hours of exposure, and significant inhibition at 10 mg/L Zn.

An alternative fuel to replace foundry coke in cupolas was developed from waste anthracite fines. Waste anthracite fines were briquetted with Si-containing materials and treated in carbothermal (combination of heat and carbon) conditions that simulated the cupola preheat zone to form silicon carbide nanowires (SCNWs). SCNWs can provide hot crushing strengths, which are important in cupola operations. Lab-scale experiments confirmed that the redox level of the Si-source significantly affected the formation of SiC. With zerovalent silicon, SCNWs were formed within the anthracite pellets. Although amorphous Si (+4) plus anthracite formed SiC, these conditions did not transform the SiC into nanowires. Moreover, under the test conditions, SiC was not formed between crystallized Si (+4) and anthracite. In a full-scale demonstration, bricks made from anthracite fines and zerovalent silicon successfully replaced a part of the foundry coke in a full-scale cupola. In addition to saving in fuel cost, replacing coke by waste anthracite fines can reduce energy consumption and CO2 and other pollution associated with conventional coking.

Simultaneous thrombosis of multiple epicardial coronary arteries is an uncommon clinical finding in ST-segment elevation myocardial infarction (STEMI). We describe a 37-year-old male present with inferior wall STEMI who was found to have large thrombi in both the right coronary artery (RCA) and the left anterior descending artery (LAD). We reviewed 23 patients with multivessel thrombosis in acute myocardial infarction in the literature. The mean age of patients was 53 +/- 14 years (32-82 years); 74% were males, and most patients had multiple risk factors for coronary artery disease. The LAD (78%) and RCA (87%) were the arteries involved for most patients. Aspiration thrombectomy was used in 3 cases. Though it is rare, STEMI with multiple culprit arteries can occur, and it is crucial to recognize this condition to determine the proper treatment, since most of these patients are critically ill.

Background While stress myocardial perfusion imaging (MPI) has strong prognostic power, it predicts the site of a subsequent acute myocardial infarction (AMI) in only 47–77% of patients. Prior studies have included small number of subjects and the interval between the stress test and the AMI has varied. The objective of the present study was to further evaluate the relationship between antecedent stress MPI and subsequent AMI. Methods We screened 600 patients admitted to our institution with acute ST-elevation MI and identified 21 patients who had a stress MPI an average of 4.8 months prior to the event. The location of perfusion defects on MPI were compared to the angiographic findings at the time of the subsequent AMI. Results Sixteen patients (76%) with AMI had defects on antecedent stress MPI while 5 patients (24%) had normal scans. Reversible or fixed perfusion defects in the territory corresponding to the site of AMI were seen in 62% of patients. All 5 patients with normal scans had multiple risk factors for coronary artery disease. Conclusion Although a normal stress MPI portends an excellent outcome, a small proportion of patients with normal scans, but with risk factors go on to develop AMI. Stress MPI has reasonable power in predicting future STEMI, but a lesser degree for the location of the future MI. Complementary imaging approaches such as coronary calcium scoring or CT angiography may be beneficial in the assessment of patients at high risk for MI.

High-speed signaling over package substrates is key to delivering the promise of 2.5D integration. Applications abound and include high-density memory interfaces, sub-division of large dies to increase yield and lower development time, sub-division of a die to achieve upward or downward scalability, or connecting to an off-chip SerDes or optics engine. Each of these in-package applications typically has high throughput and onerously low power constraints along with a low-loss channel. Several solutions have been proposed. Interposer substrates [1], or Chip-on-Substrate-on-Wafer [2] allow for very high-density wiring and low power using CMOS transceivers. Their high manufacturing and testing cost makes them prohibitive for anything but high-end applications. A different approach using high-speed ground-referenced single-ended signaling is reported in [3], which is intended for shorter channels up to 4.5mm and a BER of 1e-12. An approach using differential signaling on up to 0.75″ of Megtron 6 material and a BER of 1e-9 is reported in [4]. A comparison is given in Fig. 10.1.1.

The continuing demand for higher bandwidth in serial interconnects has pushed the symbol rate of differential lanes into the high-insertion-loss region of channels. Multi-level signaling such as differential PAM-4 [1] has been used to mitigate the loss of electrical channels by lowering the signal spectrum. Such an approach suffers from lower SNR tolerance as well as higher susceptibility to crosstalk and ISI as compared to differential signaling (DS). Coded differential approaches have been reported [2] to mitigate ISI. Our approach is a generalization of DS in which ternary values are transmitted on an 8-wire bus. The set of transmitted values belongs to a code consisting of 256 code-words called the 8b8w-code (8-bits-on-8-wires) [3]. The specific correlations in the code-words of the 8b8w-code eliminate transmit common-mode and simultaneous switching output (SSO) noise and allow for detection via self-referencing comparators (unlike PAM-4), which provides additional noise immunity. Compared to DS, the 8b8w-code offers twice the throughput at 50% of the line power. Compared to PAM-4, the code offers better SNR (3dB) at 38% of the line power with enhanced tolerance of ISI and lower crosstalk generation. The design and experimental verification of an 8b8w transceiver in 40nm CMOS is described. Transmission is achieved up to 12Gb/s per wire over 55cm of Rogers with up to 15dB loss.