Diaphragm Pump With Resonant Piezoelectric Drive

A diaphragm pump driven by a piezoelectric actuator is undergoing development. This pump is intended to be a prototype of lightweight, highly reliable pumps for circulating cooling liquids in protective garments and high-power electronic circuits, and perhaps for some medical applications. The pump would be highly reliable because it would contain no sliding seals or bearings that could wear, the only parts subject to wear would be two check valves, and the diaphragm and other flexing parts could be designed, by use of proven methods, for extremely long life. Because the pump would be capable of a large volumetric flow rate and would have only a small dead volume, its operation would not be disrupted by ingestion of gas, and it could be started reliably under all conditions. The prior art includes a number piezoelectrically actuated diaphragm pumps. Because of the smallness of the motions of piezoelectric actuators (typical maximum strains only about 0.001), the volumetric flow rates of those pumps are much too small for typical cooling applications. In the pump now undergoing development, mechanical resonance would be utilized to amplify the motion generated by the piezoelectric actuator and thereby multiply the volumetric flow rate. The prime mover in this pump would be a stack of piezoelectric ceramic actuators, one end of which would be connected to a spring that would be part of a spring-and-mass resonator structure. The mass part of the resonator structure would include the pump diaphragm (see Figure 1). Contraction of the spring would draw the diaphragm to the left, causing the volume of the fluid chamber to increase and thereby causing fluid to flow into the chamber. Subsequent expansion of the spring would push the diaphragm to the right, causing the volume of the fluid chamber to decrease, and thereby expelling fluid from the chamber. The fluid would enter and leave the chamber through check valves. The piezoelectric stack would be driven electrically to make it oscillate at the resonance frequency of the spring and- mass structure. This frequency could be made high enough (of the order of 400 Hz) that the masses of all components could be made conveniently small. The resonance would amplify the relatively small motion of the piezoelectric stack (a stroke of the order of 10 m) to a diaphragm stroke of the order of 0.5 mm. The exact amplification factor would depend on the rate of damping of oscillations; this, in turn, would depend on details of design and operation, including (but not limited to) the desired pressure rise and volumetric flow rate. In order to obtain resonance with large displacement, the damping rate must be low enough that the energy imparted to the pumped fluid on each stroke is much less than the kinetic and potential energy exchanged between the mass and spring during each cycle of oscillation. To minimize the power demand of the pump, a highly efficient drive circuit would be used to excite the piezoelectric stack. This circuit (see Figure 2) would amount to a special-purpose regenerative, switching power supply that would operate in a power-source mode during the part of an oscillation cycle when the excitation waveform was positive and in a power-recovery mode during the part of the cycle when the excitation waveform was negative. The circuit would include a voltage-boosting dc-to-dc converter that would convert between a supply potential of 24 Vdc and the high voltage needed to drive the piezoelectric stack. Because of the power-recovery feature, the circuit would consume little power. It should be possible to build the circuit as a compact unit, using readily available components

Development of Aeroservoelastic Analytical Models and Gust Load Alleviation Control Laws of a SensorCraft Wind-Tunnel Model Using Measured Data

Aeroservoelastic (ASE) analytical models of a SensorCraft wind-tunnel model are generated using measured data. The data was acquired during the ASE wind-tunnel test of the HiLDA (High Lift-to-Drag Active) Wing model, tested in the NASA Langley Transonic Dynamics Tunnel (TDT) in late 2004. Two time-domain system identification techniques are applied to the development of the ASE analytical models: impulse response (IR) method and the Generalized Predictive Control (GPC) method. Using measured control surface inputs (frequency sweeps) and associated sensor responses, the IR method is used to extract corresponding input/output impulse response pairs. These impulse responses are then transformed into state-space models for use in ASE analyses. Similarly, the GPC method transforms measured random control surface inputs and associated sensor responses into an AutoRegressive with eXogenous input (ARX) model. The ARX model is then used to develop the gust load alleviation (GLA) control law. For the IR method, comparison of measured with simulated responses are presented to investigate the accuracy of the ASE analytical models developed. For the GPC method, comparison of simulated open-loop and closed-loop (GLA) time histories are presented

The message on the bottle:Rethinking plastic labelling to better encourage sustainable use

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordPlastic pollution continues to worsen globally in volume and complexity. The complexity in plastic production, use and disposal is significant, highlighting the importance of clear communication to consumers. Yet despite this, poor plastic labelling is clear, evident from poor waste management metrics even in the most equipped countries. Plastic labelling must change to contribute to a holistic intervention on global plastic mismanagement. Discussion on this topic leads to three key recommendations: 1. An accurate and clear “sustainability scale” to empower consumers to make decisions informed by environmental and human health implications; 2. Directions for appropriate disposal action in the region of purchase; 3. A comprehensive list of plastic composition, including additives.Natural Environment Research Council (NERC)QUEX InstituteQueensland Health, AustraliaMinderoo Foundation, Australi

Молекулярно-генетическая характеристика образцов озимой мягкой пшеницы в связи с селекцией на устойчивость к полеганию

The objective of the study was to analyze the genomic structure and allelic composition of the dwarfing Rht-B1, Rht-D1 and Rht8 genes in 37 varieties and breeding samples of soft winter wheat in connection with breeding for lodging resistance in the Republic of Belarus. The molecular cytogenetic marking (C-banding) and DNA typing of genotypes were used. As a result, the analysis of the chromosomal composition of the breeding material showed that 21 winter wheat samples are characterized by the standard karyotype with the genomic structure AABBDD (2n = 42). Five variants of translocations affecting the chromosomes 1B, 3B, 5B, 6B, and 7B were revealed in the karyotypes of the remaining samples. It was found that the chromosomes of the 2nd and 4th homologous groups, in which the main dwarfing genes (Rht-B1, Rht-D1, and Rht8) are localized, did not undergo structural changes. Genotyping showed that 45.9 % of the samples contain one of the dwarfing alleles (Rht-B1b, Rht-D1b, Rht8c) in their genotype. A combination of two commercially significant alleles (Rht-B1b and Rht8c) in the genotype were identified in one of the winter wheat samples. The genotype with a combination of the Rht-B1a, Rht-D1a and Rht8b alleles occurred with the highest frequency (37.8 %) in the analysed breeding material. The Rht-B1b, Rht-D1a, Rht8b; Rht-B1a, Rht-D1a, Rht8a genotypes showed the frequency of 16.2 %. The Rht-B1a, Rht-D1a, Rht8c; Rht-B1a, Rht-D1b, Rht8b; Rht-B1a, Rht-D1b, Rht8j genotypes were identified in 5.4 % of the samples; the Rht-B1a, Rht-D1b, Rht8а genotypes – in 8.1 % of the samples. The analysis of the plant height, taking into account the karyotyping and genotyping data showed that the targeted selection of the most efficient allelic combinations of dwarfing genes is important for the cultivation region. The studies carried out allow us to suggest that the selection by the overwintering level can contribute to the fixation of the Rht8b allele in the breeding material, which is apparently associated with better winter hardiness in the conditions of Belarus.Цель – анализ геномной структуры и аллельного состава генов короткостебельности Rht-B1, Rht-D1 и Rht8 у 37 сортов и селекционных образцов озимой мягкой пшеницы в связи с селекцией на устойчивость к полеганию в Республике Беларусь. Методы. Молекулярно-цитогенетическое маркирование (С-бэндинг) и ДНК-типирование генотипов. Результаты. В ходе анализа хромосомного состава селекционного материала установлено, что 21 образец озимой пшеницы характеризуется стандартным кариотипом с геномной структурой AABBDD (2n = 42). В кариотипах остальных образцов выявлено пять вариантов транслокаций, затрагивающих хромосомы 1В, 3В, 5В, 6В и 7В. Установлено, что хромосомы 2-й и 4-й гомеологичных групп, в которых локализованы основные гены короткостебельности Rht-B1, Rht-D1 и Rht8, не подверглись структурным изменениям. В результате генотипирования показано, что 45,9 % образцов содержат в генотипе один из аллелей короткостебельности (Rht-B1b, Rht-D1b, Rht8с). Сочетание в генотипе двух коммерчески значимых аллелей короткостебельности Rht-B1b и Rht8с выявлено у одного образца озимой пшеницы. С наибольшей частотой (37,8 %) в проанализированном селекционном материале встречался генотип с комбинацией аллелей Rht-B1а, Rht-D1а и Rht8b. С частотой 16,2 % присутствовали генотипы Rht-B1b, Rht-D1а, Rht8b; Rht-B1а, Rht-D1а, Rht8а. Генотипы Rht-B1а, Rht-D1а, Rht8с; Rht-B1а, Rht-D1b, Rht8b; Rht-B1а, Rht-D1b, Rht8j выявлены у 5,4 % образцов, генотип Rht-B1а, Rht-D1b, Rht8а – у 8,1 % образцов. Заключение. Анализ высоты растения с учетом данных кариотипирования и генотипирования показал важность целенаправленного подбора наиболее эффективных для региона возделывания сочетаний аллелей генов короткостебельности. Проведенные исследования позволили предположить, что отбор по уровню перезимовки может способствовать закреплению в селекционном материале аллеля Rht8b, ассоциированного, по-видимому, с лучшей зимостойкостью в условиях Беларуси

Neural networks for genetic epidemiology: past, present, and future

During the past two decades, the field of human genetics has experienced an information explosion. The completion of the human genome project and the development of high throughput SNP technologies have created a wealth of data; however, the analysis and interpretation of these data have created a research bottleneck. While technology facilitates the measurement of hundreds or thousands of genes, statistical and computational methodologies are lacking for the analysis of these data. New statistical methods and variable selection strategies must be explored for identifying disease susceptibility genes for common, complex diseases. Neural networks (NN) are a class of pattern recognition methods that have been successfully implemented for data mining and prediction in a variety of fields. The application of NN for statistical genetics studies is an active area of research. Neural networks have been applied in both linkage and association analysis for the identification of disease susceptibility genes

Bladder Sparing Approaches for Muscle-Invasive Bladder Cancers.

OPINION STATEMENT: Organ preservation has been increasingly utilised in the management of muscle-invasive bladder cancer. Multiple bladder preservation options exist, although the approach of maximal TURBT performed along with chemoradiation is the most favoured. Phase III trials have shown superiority of chemoradiotherapy compared to radiotherapy alone. Concurrent chemoradiotherapy gives local control outcomes comparable to those of radical surgery, but seemingly more superior when considering quality of life. Bladder-preserving techniques represent an alternative for patients who are unfit for cystectomy or decline major surgical intervention; however, these patients will need lifelong rigorous surveillance. It is important to emphasise to the patients opting for organ preservation the need for lifelong bladder surveillance as risk of recurrence remains even years after radical chemoradiotherapy treatment. No randomised control trials have yet directly compared radical cystectomy with bladder-preserving chemoradiation, leaving the age-old question of superiority of one modality over another unanswered. Radical cystectomy and chemoradiation, however, must be seen as complimentary treatments rather than competing treatments. Meticulous patient selection is vital in treatment modality selection with the success of recent trials within the field of bladder preservation only being possible through this application of meticulous selection criteria compared to previous decades. A multidisciplinary approach with radiation oncologists, medical oncologists, and urologists is needed to closely monitor patients who undergo bladder preservation in order to optimise outcomes

Genetic effects on gene expression across human tissues

Characterization of the molecular function of the human genome and its variation across individuals is essential for identifying the cellular mechanisms that underlie human genetic traits and diseases. The Genotype-Tissue Expression (GTEx) project aims to characterize variation in gene expression levels across individuals and diverse tissues of the human body, many of which are not easily accessible. Here we describe genetic effects on gene expression levels across 44 human tissues. We find that local genetic variation affects gene expression levels for the majority of genes, and we further identify inter-chromosomal genetic effects for 93 genes and 112 loci. On the basis of the identified genetic effects, we characterize patterns of tissue specificity, compare local and distal effects, and evaluate the functional properties of the genetic effects. We also demonstrate that multi-tissue, multi-individual data can be used to identify genes and pathways affected by human disease-associated variation, enabling a mechanistic interpretation of gene regulation and the genetic basis of diseas