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The ever-increasing demand for higher bandwidth and lower loss makes the predictability of high-speed interconnect performance increasingly challenging. Validating models against measurements of manufactured test structures requires not only accurate methodology but also understanding of the uncertainty impact. S-parameter measurements, characterization of materials, manufacturing processes, and models constructed based on measured inputs all cause uncertainty in the performance metrics of interest. Therefore, it is critical to anticipate the results with the associated uncertainty to assess the correlation quality more objectively. This article investigates the reproducibility of measurements required for high-speed package interconnect validation through rigorous analysis and presents a methodology to quantify the impact of measurement uncertainty on commonly used performance metrics.

This report describes a technique for measuring lung shunt fraction (LSF) twice in a single session during planning arteriography for radioembolization using low and standard dose technetium-99m macroaggregated albumin (99mTc-MAA). A patient with a 16.0 cm hepatocellular carcinoma and LSF of 70% was treated with lenvatinib for 4 weeks. Planning arteriography with administration of 0.5 millicuries of 99mTc-MAA was then performed. Arterial access was maintained while the LSF was calculated, which was persistently elevated at 54%. Embolization of arteriovenous shunts was performed during the same session and 5.0 millicuries of 99mTc-MAA were administered. The repeat LSF was 29%. Successful radioembolization was subsequently performed.

Intel's microprocessors are powered by high-frequency fully-integrated switching regulators implemented on die. Current products use non-magnetic inductors designed in the package substrate. This article investigates the use of magnetic thin film inductors fabricated on silicon wafers as an alternative that improves conversion efficiency while achieving higher inductance per area density. This article builds on the earlier work done on thin film inductors at Intel, and explores the feasibility of using them in a high volume product. A number of different design variations are studied to look at tradeoffs between efficiency, saturation characteristics, transient response, and voltage ripple. This is accomplished through a combination of passive measurements using a vector network analyzer (VNA) and active measurements on a fully functioning integrated voltage regulator system.

The package integrated inductors employed by Intel's Fully Integrated Voltage Regulator (FIVR) have had to scale in tandem with the circuits they power. This reduction in available volume has resulted in degraded inductor quality factor and reduced conversion efficiency. In this work, a novel coaxial magnetic composite core inductor, called Coax MIL, is described. Coax MIL dramatically improves inductor performance and quality factor. This improvement in inductor metrics translates to reduced ripple current and enhanced efficiency.

The central nervous system (CNS) plays a key role in the sense-and-respond system which maintains proper energy stores. However, the molecular, cellular, and circuit mechanisms through which the CNS achieves this goal is poorly understood. We have recently identified the dorsal raphe nucleus (DRN) as a key node in the CNS, responsible for regulating numerous aspects of energy balance. Neurons within the DRN can potently regulate feeding, thermogenesis, and locomotor activity, and prolonged changes in their activity can ultimately drive changes in body weight. Despite playing a key role in regulating energy homeostasis, the molecular heterogeneity of the DRN had, until recently, hindered further progress in understanding it’s intricate role in the regulation of body weight. Here, we use a combination of nuclear labeling, sorting, and single-nuclear RNA-sequencing to identify the component cell types of key DRN populations, themselves known to regulate the various facets of energy balance. In particular, we identify over twenty candidate subpopulations of DRN neurons, principally defined by the neurotransmitters serotonin, glutamate, and GABA. Many of the subpopulations of these ‘principal’ cell types differentially express peptides, receptors, and signaling molecules that are directly implicated in the regulation of energy balance. We have begun to validate the expression and neuroanatomy of these molecules, including such neuropeptides as thyrotropin-releasing hormone and neuropeptide Y, and we have leveraged available recombinase-driver lines to modulate the activity of neurons expressing these genes to effectively assay their function. Together, this work represents important progress towards identifying the key cell subtypes that regulate the various aspects of energy balance. Disclosure V. M. Bhave: None. M. J. Hill-oliva: None. N. Kamatkar: None. S. Chowdhury: None. A. R. Nectow: None. Funding American Diabetes Association/Pathway to Stop Diabetes (1-18-ACE-49 to A.R.N.)

Plants actively regulate excess absorbed energy to protect photosynthetic machinery through heat dissipation in a process known as non-photochemical quenching (NPQ), a process useful for quantifying plant health and productivity. NPQ can be indirectly measured in the visible wavelengths between 500 nm and 560 nm, most commonly through the Photochemical Reflectance Index (PRI). However, there remains a lack of consensus regarding the optimal functional form and band selection to calculate PRI for the purpose of measuring NPQ mechanisms. Here, we quantitatively evaluate the effectiveness of leaf-level parametric and non-parametric spectral formulations, band locations, and number of bands to track the xanthophyll pigment cycle in a tall mature Eucalypt forest. Subsequently, our recommended approach is the new ‘tri-PRI’ index robust to constitutive pigment pool sizes across the canopy profile. tri-PRI is a Triangular Vegetation Index (TVI) (tri-PRI = 0.5[(520 - 490)(R545nm - R490nm) - (545 – 490)(R520nm - R490nm)]) using three reflectance bands around 490 nm, 520 nm and 545 nm, and has a physiological photosynthetic basis. We found that tri-PRI significantly outperformed PRI and other two band combinations for quantifying the xanthophyll EPoxidation State ‘EPS’ (tri-PRI R2 = 0.75 versus PRI R2 = 0.23), as well as the Φ NPQ and Φ PSII active chlorophyll fluorescence quenching yields. The new band placement enhanced the dynamic EPS absorption peak, while the third band provided an additional normalisation to minimise the confounding effects of pigments with overlapping spectral features. tri-PRI also performed comparably to parametric and non-parametric hyperspectral techniques and formulations using continuous spectral regions, highlighting the utility of targeted multispectral indices over hyperspectral approaches. This leaf-level study represents a foundational step toward indirectly measuring dynamic photosynthetic activity across the canopy profile in a tall mature Eucalypt forest to inform upscaling efforts from above-canopy remote sensing platforms. The application of tri-PRI and other top-performing multi-band TVI formulations for predicting EPS presented here should be explored across different canopy types, temporal-, and spatial scales.

Mapping the spatial distribution of woody and herbaceous vegetation in high temporal resolution in savannas would be beneficial for modeling interrelationships between trees and grasses, and monitoring fuel loads and biomass for livestock. In this study, we developed a frequency decomposition method to separate woody and herbaceous vegetation components using Normalized Difference Vegetation Index (NDVI) time series. The results were validated using fractional cover data derived from high-resolution images. The validation revealed a close relationship between our decomposed NDVI and corresponding fractional cover (R2 = 0.55 and 0.64 for woody and herbaceous components, respectively). We examined the spatial and temporal patterns of the decomposed NDVI, where woody and herbaceous NDVI showed different responses to precipitation. The methods proposed in this study can be used to separate the woody and herbaceous NDVI time series as an alternative approach for monitoring woody and herbaceous vegetation interrelationships related to climatic drivers.

Vegetation Fractional Cover (VFC) is an important indicator of the condition of the terrestrial surface of the Earth. The dynamics of bare soil (BS), non-photosynthetic vegetation (NPV) and photosynthetic vegetation (PV) fractions reveal patterns of growth, senescence, dormancy and regeneration. The dynamics also reveal trends in land cover and land use management across the globe. Analysis of satellite data has indicated increasing greenness of the land surface however the dynamics of the NPV and BS fractions are equally important indicators of many elements of ecosystem function and sustainability. In this study, we provide a comprehensive assessment of trends in VFC for the global terrestrial land surface based on a trend analysis over the period 2001–2018 using the Global Vegetation Fractional Cover Product. Trends were analysed by Mann-Kendell regressions over 18 years for each month of the year. Monthly maps of significant trend areas were aggregated to provide seasonal assessments. Areas and percentage areas of positive and negative trends were compiled for United Nations Subregions, Countries and Ecoregions. Significant negative trends in BS occurred across 20 M km2 of the terrestrial land surface. Although the areas of negative trends in BS were largest in China and India, the top 24 countries by area were widely distributed across the world. However, BS increased significantly across more than 11 M km2. Eleven of the top 24 ranked countries for area of increasing BS were in Africa. Substantial areas exhibited negative trends in NPV split between China and India where PV was increasing, and drylands in Asia and Africa where BS was increasing. Analysis of covariate factors at country scale inferred an association between significant increase in BS and long-term drought and increases in livestock populations. The positive trends in BS and negative trends in NPV are indicators of current and future risk for soil erosion, habitat change, and reduction in ecosystem health across heavily populated regions of the developing world.