A modified figure of merit for pyroelectric energy harvesting

This paper reports a new figure of merit for the selection of pyroelectric materials for thermal energy harvesting applications, for example, when the material is exposed to heat or radiation of a specified power density. The figure of merit put forward and developed is of interest to those selecting materials for the design of thermal harvesting devices or the development of novel ceramic, single-crystal and composite materials for pyroelectric harvesting application

A novel pyroelectric generator utilising naturally driven temperature fluctuations from oscillating heat pipes for waste heat recovery and thermal energy harvesting

Low temperature thermal to electrical energy converters have the potential to provide a route for recovering waste energy. In this paper, we propose a new configuration of a thermal harvester that uses a naturally driven thermal oscillator free of mechanical motion and operates between a hot heat source and a cold heat sink. The system exploits a heat induced liquid-vapour transition of a working fluid as a primary driver for a pyroelectric generator. The two-phase instability of a fluid in a closed looped capillary channel of an oscillating heat pipe (OHP) creates pressure differences which lead to local high frequency temperature oscillations in the range of 0.1–5 K. Such temperature changes are suitable for pyroelectric thermal to electrical energy conversion, where the pyroelectric generator is attached to the adiabatic wall of the OHP, thereby absorbing thermal energy from the passing fluid. This new pyroelectric-oscillating heat pipe (POHP) assembly of a low temperature generator continu- ously operates across a spatial heat source temperature of 55 C and a heat sink temperature of 25 C, and enables waste heat recovery and thermal energy harvesting from small temperature gradients at low temperatures. Our electrical measurements with lead zirconate titanate (PZT) show an open circuit voltage of 0.4 V (AC) and with lead magnesium niobate–lead titanate (PMN-PT) an open circuit volt- age of 0.8 V (AC) at a frequency of 0.45 Hz, with an energy density of 95 pJ cm 3 for PMN-PT. Our novel POHP device therefore has the capability to convert small quantities of thermal energy into more desirable electricity in the nW to mW range and provides an alternative to currently used batteries or centralised energy generation

Gender-Specific Metabolomics Approach to Kidney Cancer

Renal cell carcinoma (RCC) is the most common form of kidney malignancy. RCC is more common among men with a 2/1 male/female incidence ratio worldwide. Given the underlying epidemiological differences in the RCC incidence between males and females, we explored the gender specific 1H NMR serum metabolic profiles of RCC patients and their matched controls. A number of differential metabolites were shared by male and female RCC patients. These RCC specific changes included lower lactate, threonine, histidine, and choline levels together with increased levels of pyruvate, N-acetylated glycoproteins, beta-hydroxybutyrate, acetoacetate, and lysine. Additionally, serum lactate/pyruvate ratio was a strong predictor of RCC status regardless of gender. Although only moderate changes in metabolic profiles were observed between control males and females there were substantial gender related differences among RCC patients. Gender specific metabolic features associated with RCC status were identified suggesting that different metabolic panels could be leveraged for a more precise diagnostic

Application of 1H NMR-based serum metabolomic studies for monitoring female patients with rheumatoid arthritis

AbstractRheumatoid arthritis is a chronic autoimmune-based inflammatory disease that leads to progressive joint degeneration, disability, and an increased risk of cardiovascular complications, which is the main cause of mortality in this population of patients. Although several biomarkers are routinely used in the management of rheumatoid arthritis, there is a high demand for novel biomarkers to further improve the early diagnosis of rheumatoid arthritis, stratification of patients, and the prediction of a better response to a specific therapy.In this study, the metabolomics approach was used to provide relevant biomarkers to improve diagnostic accuracy, define prognosis and predict and monitor treatment efficacy. The results indicated that twelve metabolites were important for the discrimination of healthy control and rheumatoid arthritis. Notably, valine, isoleucine, lactate, alanine, creatinine, GPC  APC and histidine relative levels were lower in rheumatoid arthritis, whereas 3-hydroxyisobutyrate, acetate, NAC, acetoacetate and acetone relative levels were higher. Simultaneously, the analysis of the concentration of metabolites in rheumatoid arthritis and 3 months after induction treatment revealed that L1, 3-hydroxyisobutyrate, lysine, L5, acetoacetate, creatine, GPC+APC, histidine and phenylalanine were elevated in RA, whereas leucine, acetate, betaine and formate were lower. Additionally, metabolomics tools were employed to discriminate between patients with different IL-17A genotypes.Metabolomics may provide relevant biomarkers to improve diagnostic accuracy, define prognosis and predict and monitor treatment efficacy in rheumatoid arthritis

Metabolomics of Human Amniotic Fluid and Maternal Plasma during Normal Pregnancy - Fig 2

<p><b>The PCA results obtained using quantified metabolites (signal areas) for amniotic fluid (A) and plasma (B).</b> Pregnancy stages. Yellow inverted triangles– 2^nd trimester (T2), red triangles– 3^rd trimester (T3), blue squares–delivery (TD) and green circles–prolonged pregnancy (PP).</p

The influence of different diets on metabolism and atherosclerosis processes—A porcine model: Blood serum, urine and tissues 1H NMR metabolomics targeted analysis

The global epidemic of cardiovascular diseases leads to increased morbidity and mortality caused mainly by myocardial infarction and stroke. Atherosclerosis is the major pathological process behind this epidemic. We designed a novel model of atherosclerosis in swine. Briefly, the first group (11 pigs) received normal pig feed (balanced diet group-BDG) for 12 months, the second group (9 pigs) was fed a Western high-calorie diet (unbalanced diet group-UDG) for 12 months, the third group (8 pigs) received a Western type high-calorie diet for 9 months later replaced by a normal diet for 3 months (regression group-RG). Clinical measurements included zoometric data, arterial blood pressure, heart rate and ultrasonographic evaluation of femoral arteries. Then, the animals were sacrificed and the blood serum, urine and skeletal muscle tissue were collected and 1H NMR based metabolomics studies with the application of fingerprinting PLS-DA and univariate analysis were done. Our results have shown that the molecular disturbances might overlap with other diseases such as onset of diabetes, sleep apnea and other obesity accompanied diseases. Moreover, we revealed that once initiated, molecular changes did not return to homeostatic equilibrium, at least for the duration of this experiment

Differences of metabolites (expressed as percentage) between the four gestational age periods.

<p>Differences of metabolites (expressed as percentage) between the four gestational age periods.</p

The characterization of the amniotic fluid and plasma samples.

<p>The characterization of the amniotic fluid and plasma samples.</p

Ultrasound measured Intima-Media complex thickness (IMT) and the mean thickness of intima, media and adventitia obtained from a histological analysis of femoral arteries at the same location as ultrasound measurements in all study groups.

<p>Ultrasound measured Intima-Media complex thickness (IMT) and the mean thickness of intima, media and adventitia obtained from a histological analysis of femoral arteries at the same location as ultrasound measurements in all study groups.</p