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Background: The kynurenine pathway (KP) comprises a family of tryptophan-derived metabolites that some studies have reported are associated with poorer cognitive performance and an increased risk of Alzheimer’s disease and related dementias (ADRD). Objective: The objective of this study was to determine the associations of plasma KP metabolites (kynurenine [KYN], kynurenic acid [KA], and tryptophan [TRP]) with a panel of plasma ADRD biomarkers (Aβ42/ β40 ratio, pTau-181, glial fibrillary acidic protein [GFAP], and neurofilament light [NfL]) and cognitive performance in a subset of older adults drawn from the Duke Physical Performance Across the LifeSpan (PALS) study. Methods: The Montreal Cognitive Assessment (MoCA) was used to assess cognitive performance. We used multivariate multiple regression to evaluate associations of the KYN/TRP and KA/KYN ratios with MoCA score and plasma ADRD biomarkers at baseline and over two years (n = 301; Age = 74.8±8.7). Results: Over two years, an increasing KYN/TRP ratio was associated with increasing plasma concentrations of plasma p-Tau181 (β= 6.151; 95% CI [0.29, 12.01]; p = 0.040), GFAP (β= 11.12; 95% CI [1.73, 20.51]; p = 0.020), and NfL (β= 11.13; 95% CI [2.745, 19.52]; p = 0.009), but not MoCA score or the Aβ42/Aβ40 ratio. There were no significant associations of KA/KYN with MoCA score or plasma ADRD biomarkers. Conclusion: Our findings provide evidence that greater concentrations of KP metabolites are associated longitudinally over two years with greater biomarker evidence of neurofibrillary tau pathology (pTau-181), neuroinflammation (GFAP), and neurodegeneration (NfL), suggesting that dysregulated KP metabolism may play a role in ADRD pathogenesis.

Maternal metabolites influence the size of newborns independently of maternal body mass index (BMI) and glycemia, highlighting the importance of maternal metabolism on offspring outcomes. This study examined associations of maternal metabolites during pregnancy with childhood adiposity, and cord blood metabolites with childhood adiposity using phenotype and metabolomic data from the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study and the HAPO Follow-Up Study. The maternal metabolites analyses included 2324 mother–offspring pairs, while the cord blood metabolites analyses included 937 offspring. Multiple logistic and linear regression were used to examine associations between primary predictors, maternal or cord blood metabolites, and childhood adiposity outcomes. Multiple maternal fasting and 1 hr metabolites were significantly associated with childhood adiposity outcomes in Model 1 but were no longer significant after adjusting for maternal BMI and/or maternal glycemia. In the fully adjusted model, fasting lactose levels were negatively associated with child BMI z-scores and waist circumference, while fasting urea levels were positively associated with waist circumference. One-hour methionine was positively associated with fat-free mass. There were no significant associations between cord blood metabolites and childhood adiposity outcomes. Few metabolites were associated with childhood adiposity outcomes after adjusting for maternal BMI and glucose, suggesting that maternal BMI accounts for the association between maternal metabolites and childhood adiposity.

To design and establish a prospective biospecimen repository that integrates multi-omics assays with clinical data to study mechanisms of controlled injury and healing.Elective surgery is an opportunity to understand both the systemic and focal responses accompanying controlled and well-characterized injury to the human body. The overarching goal of this ongoing project is to define stereotypical responses to surgical injury, with the translational purpose of identifying targetable pathways involved in healing and resilience, and variations indicative of aberrant peri-operative outcomes.Clinical data from the electronic medical record combined with large-scale biological data sets derived from blood, urine, fecal matter, and tissue samples are collected prospectively through the peri-operative period on patients undergoing 14 surgeries chosen to represent a range of injury locations and intensities. Specimens are subjected to genomic, transcriptomic, proteomic, and metabolomic assays to describe their genetic, metabolic, immunologic, and microbiome profiles, providing a multidimensional landscape of the human response to injury.The highly multiplexed data generated includes changes in over 28,000 mRNA transcripts, 100 plasma metabolites, 200 urine metabolites, and 400 proteins over the longitudinal course of surgery and recovery. In our initial pilot dataset, we demonstrate the feasibility of collecting high quality multi-omic data at pre- and postoperative time points and are already seeing evidence of physiologic perturbation between timepoints.This repository allows for longitudinal, state-of-the-art geno-mic, transcriptomic, proteomic, metabolomic, immunologic, and clinical data collection and provides a rich and stable infrastructure on which to fuel further biomedical discovery.

Hypersecretion of amylin, a β-cell hormone that regulates satiation, is common in individuals with prediabetes and is associated with pancreatic amyloid deposition and type-2 diabetes. Evidence has emerged that increased circulating levels of amyloid-forming human amylin may potentially impair brain function. Because mouse amylin is non-amyloidogenic, we generated transgenic mice with conditional pancreatic expression of amyloid-forming human amylin to study how in vivo knockdown of human amylin expression influences brain function during the development of type-2 diabetes. Males and females were fed a high-fat diet starting at 3 months of age to induce amylin hypersecretion and glucose dysregulation. Males developed hyperglycemia at 5 months of age, whereas females showed glucose dysregulation 3-4 months later. At 5 months of age, human amylin-expressing male mice were randomly assigned to either amylin downregulation group (by peritoneal tamoxifen injection) or control group (maintained amylin expression) (n = 10/group). Two months later, we assessed brain function with the novel object recognition test and performed comparative non-targeted metabolomics and global RNA-seq analyses of hippocampal tissue. Mice with downregulated human amylin show enhanced recognition memory index (p < 0.001) and lower blood glucose levels (p < 0.001) compared to those that continued to express human amylin. This was associated with increased hippocampal levels of glycolysis metabolites, including lactic acid (p < 0.01), glucose-6-phosphate (p = 0.06), and fructose (p = 0.07). Hippocampal gene-expression patterns between the two mouse groups revealed extensive compensatory changes in gene expression related to glucose metabolism. In conclusion, amylin downregulation in diabetic mice improves systemic glucose homeostasis and memory. Molecular processes associated with improved memory involve increased hippocampal glycolytic fluxes and compensatory gene expression.

Insulin resistance (IR) in adolescents with obesity is associated with a sex-dependent metabolic 'signature' comprising the branched-chain amino acids (BCAAs), glutamate/glutamine, C3/C5 acylcarnitines and uric acid. Here, we compared the levels of branched-chain α-keto acids (BCKAs) and glutamate/glutamine, which are the byproducts of BCAA catabolism and uric acid among adolescents with obesity prior to and following a 6-month lifestyle-intervention program.Fasting plasma samples from 33 adolescents with obesity (16 males, 17 females, aged 12-18 year) were analysed by flow-injection tandem MS and LC-MS/MS. Multiple linear regression models were used to correlate changes in BCKAs, glutamate/glutamine and uric acid with changes in weight and insulin sensitivity as assessed by HOMA-IR, adiponectin and the ratio of triglyceride (TG) to HDL. In predictive models, BCKAs, glutamate/glutamine and uric acid at baseline were used as explanatory variables.Baseline BCKAs, glutamate/glutamine and uric acid were higher in males than females despite comparable BMI-metrics. Following lifestyle-intervention, α-keto-β-methylvalerate (α-KMV, a metabolic by product of isoleucine) decreased in males but not in females. The ratio of BCKA/BCAA trended lower in males. In the cohort as a whole, BCKAs correlated positively with the ratio of TG to HDL at baseline and HOMA-IR at 6-month-follow-up. Glutamate/glutamine was positively associated with HOMA-IR at baseline and 6-month-follow-up. A reduction in BCKAs was associated with an increase in adiponectin, and those with higher BCKAs at baseline had higher adiponectin levels at 6-month-follow-up. Interestingly those adolescents with higher uric acid levels at baseline had greater reduction in weight.BCKAs and glutamate/glutamine may serve as biomarkers of IR in adolescents with obesity, and uric acid might serve as a predictor of weight loss in response to lifestyle-intervention. Differential regulation of BCAA catabolism in adolescent males and females implicates critical roles for sex steroids in metabolic homeostasis.

Context Gestational diabetes is associated with a long-term risk of developing a disorder of glucose metabolism. However, neither the metabolic changes characteristic of gestational diabetes in a large, multi-ancestry cohort nor the ability of metabolic changes during pregnancy, beyond glucose levels, to identify women at high risk for progression to a disorder of glucose metabolism has been examined. Objective This work aims to identify circulating metabolites present at approximately 28 weeks’ gestation associated with gestational diabetes mellitus (GDM) and development of a disorder of glucose metabolism 10 to 14 years later. Methods Conventional clinical and targeted metabolomics analyses were performed on fasting and 1-hour serum samples following a 75-g glucose load at approximately 28 weeks’ gestation from 2290 women who participated in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study. Postpartum metabolic traits included fasting and 2-hour plasma glucose following a 75-g glucose load, insulin resistance estimated by the homeostasis model assessment of insulin resistance, and disorders of glucose metabolism (prediabetes and type 2 diabetes) during the HAPO Follow-Up Study. Results Per-metabolite analyses identified numerous metabolites, ranging from amino acids and carbohydrates to fatty acids and lipids, before and 1-hour after a glucose load that were associated with GDM as well as development of a disorder of glucose metabolism and metabolic traits 10 to 14 years post partum. A core group of fasting and 1-hour metabolites mediated, in part, the relationship between GDM and postpartum disorders of glucose metabolism, with the fasting and 1-hour metabolites accounting for 15.7% (7.1%-30.8%) and 35.4% (14.3%-101.0%) of the total effect size, respectively. For prediction of a postpartum disorder of glucose metabolism, the addition of circulating fasting or 1-hour metabolites at approximately 28 weeks’ gestation showed little improvement in prediction performance compared to clinical factors alone. Conclusion The results demonstrate an association of multiple metabolites with GDM and postpartum metabolic traits and begin to define the underlying pathophysiology of the transition from GDM to a postpartum disorder of glucose metabolism.

Objectives We have previously demonstrated that insulin resistance (IR) in youth is associated with elevated levels of branched-chain amino acids (BCAAs). BCAAs compete with aromatic amino acids (AAA) including tryptophan, the precursor of serotonin, for uptake into β-cells and other tissues via the large neutral amino acid transporter. Serotonin has been reported to increase β-cell mass and glucose-dependent insulin secretion. In this study we have explored how BCAA, tryptophan (one of the AAA), and a subset of their metabolites are modulated in youth-onset T2D. Based on our prior studies in neuronal BCAA metabolism, we hypothesized that elevated BCAA could induce diversion of tryptophan metabolism towards production of kynurenine rather than serotonin in youth with T2D. To test this, we analyzed 24-hour urine samples and compared levels of byproducts of BCAAs and tryptophan metabolism in obese youth with T2D with those in non-diabetic obese and lean youth of comparable age, pubertal status and ethnicity. Methods 56 non-diabetic adolescents with overweight/obesity ("obese"), 42 adolescents with T2D ("T2D"), and 43 normal weight controls ("lean"), ages 12-21 years-old were studied. Weight, height, BMI, BMI% were extracted from medical charts. Body fat percent (BF%) was measured by TANITA. We also measured metabolites derived from BCAA catabolism, including the branched-chain ketoacids (BCKAs), and tryptophan metabolism, including intermediates of the serotonergic and kynurenine pathways, in spot and 24-hour urine samples by liquid chromatography/tandem-mass spectrometry (LC/MS-MS). Levels were normalized to urine creatinine. Group differences were assessed by Kruskal Wallis or ANOVA. Results Groups were comparable for age (obese 14.8 +/- 1.9; T2D 15.7 +/- 2.1 and lean 14.9 +/- 1.9-yr), pubertal status, and ethnicity. Youth with T2D were predominantly female (T2D, 28 F, 14 M; obese 33 F, 23 M and lean, 17 F, 26 M), and had highest BF% (obese 37.3 +/- 9.5; T2D 42.9 +/- 9.9; lean 20.1 +/- 6.3%; p=2.58e-22). In 24-hour urine samples, BCKAs, tryptophan, and kynurenine levels were higher in T2D (p=0.0002, p= 0.0045 and p= 0.00009 respectively) than in either lean controls or nondiabetic youth with obesity; in contrast, there were no differences between lean controls and non-diabetic youth with obesity. The levels of 5-HIAA, the principal metabolite of serotonin, were comparable across groups; however, the ratio of kynurenine/tryptophan was higher (p= 0.0112) in youth with T2D and the ratios of 5-HIAA/ tryptophan (p=0.027) and 5-HIAA/Kynurenine (p=0.0067) were lower compared to the other two groups. Those ratios were comparable between lean controls and non-diabetic youth with obesity. Conclusions Increased BCKAs are accompanied by diversion of tryptophan metabolism from the serotonin pathway to the kynurenine pathway, suggesting perturbations in both BCAA and AAA metabolism in youth-onset T2D. These alterations could contribute to development of beta-cell dysfunction and progression to T2D in youth. Presentation: Sunday, June 12, 2022 12:00 p.m. - 12:15 p.m.

Objectives In healthy, normal - weight adults there is a circadian rhythm in blood pressure (BP) and plasma catecholamines (epinephrine and norepinephrine): BP and the levels of norepinephrine and epinephrine decline during sleep, followed by a rapid increase during the early morning hours. Studies in adults with Type 2 diabetes (T2D) show blunted reductions in BP and plasma catecholamine levels during sleep that are associated with increased risks for heart failure, stroke, myocardial infarction, and sudden death. In this study, we explored if the circadian rhythm in catecholamines is disrupted in youth-onset T2D. We hypothesized that increased sympatho-adrenal activity during sleep differentiates youth with T2D from non-diabetic overweight/obese and lean youth of comparable age, pubertal status, and ethnicity. To that end, we measured urine catecholamines in fasting – morning-spot urines and 24-hour urine samples. Methods 56 non-diabetic adolescents with overweight/obesity ("obese"), 42 adolescents with T2D ("T2D"), and 43 normal-weight controls ("lean"); aged 12-21 years, were studied. None was diagnosed with hypertension, and none was on antihypertensive treatment. Weight, height, BMI, BMI%, and BP were extracted from medical charts. Body fat percent (BF%) was measured by TANITA. Stress levels were assessed using PHQ-2 and PHQ-9 questionnaires. Fractionated free urine catecholamines (epinephrine, norepinephrine, and dopamine) were analyzed by liquid chromatography/tandem mass spectrometry (LC/MS-MS) in both spot and 24-hour urines, normalized to urinary creatinine. The ratio of fasting morning urine catecholamines to 24-hour urine catecholamines was calculated to assess circadian variation in catecholamines. Group differences were assessed by Kruskal-Wallis or ANOVA. Results Groups were comparable for age (obese 14.8 +/- 1.9; T2D 15.7 +/- 2.1 and lean 14.9 +/- 1.9-yr), pubertal status, and ethnicity. Obese youth with and without T2D were predominantly female (T2D, 28 F, 14 M; obese 33 F, 23 M; lean, 17 F, 26 M); those with T2D had highest BF% (obese 37.3 +/- 9.5; T2D 42.9 +/- 9.9; lean 20.1 +/- 6.3%; p=2.58e-22) and systolic blood pressure (obese 115.36 +/- 11.54; T2D 127.83 +/- 12.08 and lean 111.65 +/- 9.13 mmHg; p=5.49e-10). Fractionated free urine catecholamines (epinephrine, norepinephrine and dopamine) were comparable across groups in 24-hour urines. However, fasting morning epinephrine levels and the ratio of fasting morning/24-hour epinephrine were higher in T2D (p=0.0035, and p=0.035, respectively) than in either lean or nondiabetic youth with obesity. There were no differences in morning urine catecholamines between lean controls and non-diabetic youth with obesity. Conclusions Our results suggest a disrupted circadian rhythm in catecholamines in youth-onset T2D, with a blunted overnight fall in epinephrine levels. Higher levels of epinephrine levels at night in youth with T2D might be associated with, or predispose to, hypertension and long-term cardiovascular complications. Presentation: Sunday, June 12, 2022 11:30 a.m. - 11:45 a.m.

Hypersecretion of amylin, a β-cell hormone that regulates satiation, is common in individuals with prediabetes and is associated with pancreatic amyloid deposition and type-2 diabetes. Evidence has emerged that increased circulating levels of amyloid-forming human amylin may potentially impair brain function. Because mouse amylin is non-amyloidogenic, we generated transgenic mice with conditional pancreatic expression of amyloid-forming human amylin to study how in vivo knockdown of human amylin expression influences brain function during the development of type-2 diabetes. Males and females were fed a high-fat diet starting at 3 months of age to induce amylin hypersecretion and glucose dysregulation. Males developed hyperglycemia at 5 months of age, whereas females showed glucose dysregulation 3-4 months later. At 5 months of age, human amylin-expressing male mice were randomly assigned to either amylin downregulation (by peritoneal tamoxifen injection) or control (maintained amylin expression) groups (n = 10/group) . Two months later, we assessed brain function with a novel object recognition test and performed comparative non-targeted metabolomics and global RNA-seq analyses of hippocampal tissue. Mice with downregulated human amylin showed enhanced recognition memory index (p < 0.001) and lower blood glucose levels (p < 0.001) compared to those that continued to express human amylin. This was associated with increased hippocampal levels of glycolysis metabolites, including lactic acid (p < 0.01) , glucose-6-phosphate (p = 0.06) , and fructose (p = 0.07) . Hippocampal gene-expression patterns between the two mouse groups revealed extensive compensatory changes in gene expression related to glucose metabolism. In conclusion, amylin downregulation in diabetic mice improves systemic glucose homeostasis and memory. Molecular processes associated with improved memory involve increased hippocampal glycolytic fluxes and compensatory gene expression. Disclosure V.Gopal viswanathan: None. M.Muehlbauer: None. J.R.Bain: Other Relationship; CardioEphEx, LLC. F.Despa: None. N.Verma: None. E.D.Winford: None. D.Kotiya: None. L.E.Radulescu: None. N.Leibold: None. K.C.Chen: None. S.Despa: None. D.A.Hill: None. Funding National Institutes of Health NS116058, AG057290, AG053999

This article describes the first case of successful nerve grafting for posterior interosseous nerve (PIN) palsy secondary to radiocapitellar joint entrapment 2 years following closed reduction (CR) of a pediatric Monteggia fracture-dislocation (MFD). Patient notes were examined. The literature was reviewed to determine whether similar cases or techniques had been reported. A 5-year-old girl presented with a PIN palsy 2 years following CR of an MFD, demonstrating Medical Research Council (MRC) grade 4 wrist and MRC grade 2 finger and thumb extension. Nerve exploration at 27 months revealed a PIN crushed in the radiocapitellar joint with a proximal neuroma-in-continuity and no response to electrical stimulation. Neurolysis and lateral antebrachial cutaneous nerve cable grafting were performed. The decision to pursue nerve grafting was based on the intraoperative appearance of an atrophic PIN with no response to stimulation, but with minimal muscle atrophy, short distance to target muscles, and pediatric patient with extended reinnervation timeline. Full recovery (MRC grade 5 wrist extension and MRC grade 4+ finger and thumb extension) was achieved at 1-year follow-up. We present the first case of successful nerve grafting for PIN palsy secondary to radiocapitellar joint entrapment 2 years following CR of a type III MFD. Even with significant treatment delay, nerve reconstruction should be considered in the pediatric population.

An acousto-Optic Modulator (AOM) formed by an Arsenic Trisulfide (As $_2$ S $_3$ ) Mach–Zehnder interferometer (MZI), operating in a push-pull configuration and placed inside a surface acoustic wave (SAW) cavity on a Y-cut Lithium Niobate (LN) wafer is demonstrated. This is the first demonstration of such acousto-optic (AO) modulator in this As $_2$ S $_3$ -LN hybrid platform. In this approach, the high index contrast of As $_2$ S $_3$ waveguides is exploited to attain a high optical confinement. Additionally, the placement of the photonic MZI inside the SAW cavity enhances the AO interaction due to the high quality factor (Q) of the SAW resonator. An analytical expression that describes such enhancement as a function of the elasto-optic (EO) coefficient of As $_2$ S $_3$ is derived in conjunction with COMSOL finite element methods to describe strain in the SAW cavity. By fitting this expression to experimental data, the EO coefficient ( $p_{11}$ and $p_{12}$ , where $p_{11} \approx p_{12}$ ) for As $_2$ S $_3$ is extracted to be 0.29 at the wavelength of 1550 nm. This is the first time that the EO coefficient of thin film As $_2$ S $_3$ is experimentally derived.

We present experimental results of relaxation oscillations based on the TaOx threshold switching devices as a function of voltage, load resistance, and the parallel capacitance. Of particular inter...

The in utero environment is important for newborn size at birth, which is associated with childhood adiposity. We examined associations between maternal metabolite levels and newborn birthweight, sum of skinfolds (SSF), and cord C-peptide in a multinational and multi-ancestry cohort of 2337 mother–newborn dyads. Targeted and untargeted metabolomic assays were performed on fasting and 1 h maternal serum samples collected during an oral glucose tolerance test performed at 24–32 week gestation in women participating in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study. Anthropometric measurements were obtained on newborns at birth. Following adjustment for maternal BMI and glucose, per-metabolite analyses demonstrated significant associations between maternal metabolite levels and birthweight, SSF, and cord C-peptide. In the fasting state, triglycerides were positively associated and several long-chain acylcarnitines were inversely associated with birthweight and SSF. At 1 h, additional metabolites including branched-chain amino acids, proline, and alanine were positively associated with newborn outcomes. Network analyses demonstrated distinct clusters of inter-connected metabolites significantly associated with newborn phenotypes. In conclusion, numerous maternal metabolites during pregnancy are significantly associated with newborn birthweight, SSF, and cord C-peptide independent of maternal BMI and glucose, suggesting that metabolites in addition to glucose contribute to newborn size at birth and adiposity.

Although hematopoietic stem cell transplantation (HCT) is the only curative treatment for acute myeloid leukemia (AML), it is associated with significant treatment related morbidity and mortality. There is great need for predictive biomarkers associated with overall survival (OS) and clinical outcomes. We hypothesized that circulating metabolic, inflammatory, and immune molecules have potential as predictive biomarkers for AML patients who receive HCT treatment. This retrospective study was designed with an exploratory approach to comprehensively characterize immune, inflammatory, and metabolomic biomarkers. We identified patients with AML who underwent HCT and had existing baseline plasma samples. Using those samples (n = 34), we studied 65 blood based metabolomic and 61 immune/inflammatory related biomarkers, comparing patients with either long-term OS (≥ 3 years) or short-term OS (OS ≤ 1 years). We also compared the immune/inflammatory response and metabolomic biomarkers in younger vs. older AML patients (≤30 years vs. ≥ 55 years old). In addition, the biomarker profiles were analyzed for their association with clinical outcomes, namely OS, chronic graft versus host disease (cGVHD), acute graft versus host disease (aGVHD), infection and relapse. Several baseline biomarkers were elevated in older versus younger patients, and baseline levels were lower for three markers (IL13, SAA, CRP) in patients with OS ≥ 3 years. We also identified immune/inflammatory response markers associated with aGVHD (IL-9, Eotaxin-3), cGVHD (Flt-1), infection (D-dimer), or relapse (IL-17D, bFGF, Eotaxin-3). Evaluation of metabolic markers demonstrated higher baseline levels of medium- and long-chain acylcarnitines (AC) in older patients, association with aGVHD (lactate, long-chain AC), and cGVHD (medium-chain AC). These differentially expressed profiles merit further evaluation as predictive biomarkers.

To combat the high energy costs of moving data between main memory and the CPU, recent works have proposed to perform processing-using-memory (PUM), a type of processing-in-memory where operations are performed on data in situ (i.e., right at the memory cells holding the data). Several common and emerging memory technologies offer the ability to perform bitwise Boolean primitive functions by having interconnected cells interact with each other, eliminating the need to use discrete CMOS compute units for several common operations. Recent PUM architectures extend upon these Boolean primitives to perform bit-serial computation using memory. Unfortunately, several practical limitations of the underlying memory devices restrict how large emerging memory arrays can be, which hinders the ability of conventional bit-serial computation approaches to deliver high performance in addition to large energy savings. In this paper, we propose RACER, a cost-effective PUM architecture that delivers high performance and large energy savings using small arrays of resistive memories. RACER makes use of a bit-pipelining execution model, which can pipeline bit-serial w-bit computation across w small tiles. We fully design efficient control and peripheral circuitry, whose area can be amortized over small memory tiles without sacrificing memory density, and we propose an ISA abstraction for RACER to allow for easy program/compiler integration. We evaluate an implementation of RACER using NOR-capable ReRAM cells across a range of microbenchmarks extracted from data-intensive applications, and find that RACER provides 107 ×, 12 ×, and 7 × the performance of a 16-core CPU, a 2304-shader-core GPU, and a state-of-the-art in-SRAM compute substrate, respectively, with energy savings of 189 ×, 17 ×, and 1.3 ×.

Background Whether differences in circulating long chain acylcarnitines (LCAC) are seen in heart failure (HF) patients with and without diabetes mellitus (DM), and whether these biomarkers report on exercise capacity and clinical outcomes, remains unknown. The objective of the current study was to use metabolomic profiling to identify biomarkers that report on exercise capacity, clinical outcomes, and differential response to exercise in HF patients with and without DM. Methods Targeted mass spectrometry was used to quantify metabolites in plasma from participants in the heart failure: a controlled trial investigating outcomes of exercise training (HF-ACTION) trial. Principal components analysis was used to identify 12 uncorrelated factors. The association between metabolite factors, diabetes status, exercise capacity, and time to the primary clinical outcome of all-cause mortality or all-cause hospitalization was assessed. Results A total of 664 participants were included: 359 (54%) with DM. LCAC factor levels were associated with baseline exercise capacity as measured by peak oxygen consumption (beta 0.86, p = 2 × 10−7, and were differentially associated in participants with and without DM (beta 1.58, p = 8 × 10−8 vs. 0.67, p = 9 × 10−4, respectively; p value for interaction = 0.012). LCAC levels changed to a lesser extent in participants with DM after exercise (mean ∆ 0.09, p = 0.24) than in those without DM (mean ∆ 0.16, p = 0.08). In univariate and multivariate modeling, LCAC factor levels were associated with time to the primary outcome (multivariate HR 0.80, p = 2.74 × 10−8), and were more strongly linked to outcomes in diabetic participants (HR 0.64, p = 3.21 × 10−9 v. HR 0.90, p = 0.104, p value for interaction = 0.001). When analysis was performed at the level of individual metabolites, C16, C16:1, C18, and C18:1 had the greatest associations with both exercise capacity and outcomes, with higher levels associated with worse outcomes. Similar associations with time to the primary clinical outcome were not found in a control group of patients without HF from the CATHeterization GENetics (CATHGEN) study. Conclusions LCAC biomarkers are associated with exercise status and clinical outcomes differentially in HF patients with and without DM. Impaired fatty acid substrate utilization and mitochondrial dysfunction both at the level of the skeletal muscle and the myocardium may explain the decreased exercise capacity, attenuated response to exercise training, and poor clinical outcomes seen in patients with HF and DM. Trial Registration clinicaltrials.gov Identifier: NCT00047437.

Heat-assisted magnetic recording (HAMR) promises to increase the areal data density in hard disk drives beyond 1 Tb/in 2 by raising the temperature of the media to its Curie temperature for writing. The metallic optical near-field transducer (NFT) is a key component of the HAMR system. It confines optical energy to a small region below the diffraction limit on the recording media. The challenge with HAMR is that the NFT can reach extreme temperatures due to self-heating. Therefore, thermal reliability of the NFT is of great importance. To help the NFT dissipate heat, AlN is a potential heat sink material with reported thermal conductivity higher than 100 W/m-K [1] . In this work, we proposed a thermally efficient HAMR light delivery system using a ridge waveguide on an AlN heat sink. The relatively large metallic waveguide structure can dissipate heat effectively even in the presence of finite interface thermal conductance while still producing a small thermal spot in the medium. The thermal efficiencies ( TE ), defined as the ratio of peak temperature rise in the medium versus in the NFT can be as high as 2.93 in our design.

Summary PURPOSE Pelvic reconstruction following abdominoperineal resection or pelvic exenteration is associated with signification surgical site morbidity. Immediate pelvic reconstruction with a muscle flap is now the gold standard, associated with reduced perineal morbidity compared to primary closure alone. 2 , 3 The purpose of the present study was to directly compare outcomes of VRAM and gracilis flap pelvic reconstruction following oncologic resection. METHODS A multicenter retrospective review was performed of 88 patients who underwent abdominoperineal resection or pelvic exenteration and immediate pelvic reconstruction, either with a VRAM (N = 61) or Gracilis flap (N = 27). Electronic medical records were analyzed for patient demographics, intraoperative data, and postoperative outcomes. Mortality, minor complication rate, major complication rate and time to complete wound healing was compared between groups. RESULTS Overall, there was no significant difference in the minor complication rate (44% gracilis vs 48% VRAM, p = 0.8), major complication rate (19% gracilis vs 13% of VRAM, p = 0.53), 30-day mortality (0% VRAM vs 0% gracilis, p = 1.0) and median time to complete wound healing (68 days vs 67 days, p = 0.19) between the gracilis and VRAM groups. Muscle-only gracilis flaps had a significantly reduced healing time compared to musculocutaneous gracilis flaps (48 days vs 85 days, p = 0.007). CONCLUSIONS The workhorse flap in pelvic reconstruction remains the VRAM. While previous studies have alluded to the inferiority of thigh based flaps compared to the VRAM, we demonstrate here that pelvic reconstruction with the gracilis flap can be performed with comparable donor and recipient complication rates and similar time to complete wound healing as the VRAM.