Low-power methods of power sensing and frequency detection for wideband vibration energy harvesting

Power maximisation techniques in wideband vibration energy harvesting typically require the periodic sensing of input power or excitation frequency. This paper presents low- power circuits and sensing methods to obtain this information. First, an excitation frequency measurement circuit is presented that permits a reduced timer run-time compared to reported methods. Second, a power sensing method is presented, which extends the measurement range of reported techniques by adapting to the levels of the available power. Experimental results for the frequency measurement circuit tested in the range 35-51 Hz show a power consumption of 3.7 μW. The power-sensing technique is experimentally validated over a power range of 370690 μW, and its power consumption is 7.5 μW

Molecular and cellular limits to somatosensory specificity

Animals detect environmental changes through sensory neural mechanisms that enable them to differentiate the quality, intensity and temporal characteristics of stimuli. The 'doctrine of specific nervous energies' postulates that the different sensory modalities experienced by humans result of the activation of specific nervous pathways. Identification of functional classes of sensory receptors provided scientific support to the concept that somatosensory modalities (touch, pain, temperature, kinesthesis) are subserved by separate populations of sensory receptor neurons specialized in detecting innocuous and injurious stimuli of different quality (mechanical forces, temperature, chemical compounds). The identification of receptor proteins activated by different physicochemical stimuli, in particular ion channels of the Transient Receptor Potential (TRP) superfamily, has put forward the concept that specificity of peripheral sensory receptor neurons is determined by their expression of a particular "molecular sensor" that confers to each functional type its selectivity to respond with a discharge of nerve impulses to stimuli of a given quality. Nonetheless, recent experimental data suggest that the various molecular sensors proposed as specific transducer molecules for stimuli of different quality are not as neatly associated with the distinct functional types of sensory receptors as originally proposed. First, many ion channel molecules initially associated to the transduction of only one particular form of energy are also activated by stimuli of different quality, implying a limited degree of specificity in their transducing capacities. Second, molecular sensors associated with a stimulus quality and hence to a sensory receptor type and ultimately to a sensory modality may be concomitantly expressed in sensory receptor neurons functionally defined as specific for another stimulus quality. Finally, activation of voltage gated channels involved primarily in nerve impulse generation can also influence the gating of transducing channels, dramatically modifying their activation profile. Thus, we propose that the capacity exhibited by the different functional types of somatosensory receptor neurons to preferentially detect and encode specific stimuli into a discharge of nerve impulses, appears to result of a characteristic combinatorial expression of different ion channels in each neuronal type that finally determines their transduction and impulse firing properties. Transduction channels don't operate in isolation and their cellular context should also be taken into consideration to fully understand their function. Moreover, the inhomogeneous distribution of transduction and voltage-gated channels at soma, axonal branches and peripheral endings of primary sensory neurons influences the characteristics of the propagated impulse discharge that encodes the properties of the stimulus. Alteration of this concerted operation of ion channels in pathological conditions may underlie the changes in excitability accompanying peripheral sensory neuron injuries

Enhancing spaceflight safety with UOS3 cubesat

Earth orbits are becoming increasingly congested. This will not only impact future space operations but also become a concern for the population on the ground; with more spacecraft being flown, more objects will re-enter the atmosphere in an uncontrolled fashion. Parts of these satellites can reach Earth surface and endanger the ground population (e.g. ROSAT or UARS satellites). A student-run project from the University of Southampton aims to build a 1U cubesat (approx. 10 by 10 by 10 cm satellite), which will gather data that will improve the accuracy of re-entry predictions. The cubesat will record and deliver its position and attitude during the orbital decay, thus providing validation data for re-entry prediction tools. This will reduce the risk to the ground population because more accurate prognoses will allow mitigation measures to be implemented in the areas at risk. The mission could also allow the risk of collision between spacecraft to be estimated more accurately thanks to improvement of the atmospheric models. This would give the decision makers more complete information to use, for instance, in collision avoidance manoeuvre plannin

The Utility of the Abstract Relational Model and Attribute Paths in SQL

It is well-known that querying information is difficult for domain experts, for they are not familiar with querying actual relational schemata due to the notions of primary and foreign keys and the various ways of representing and storing information in a relational database. To overcome these problems, the Abstract Relational Model and the query language, SQLP, have been proposed. They are the theoretical foundations and ensure that explicit primary and foreign keys are hidden from the user's view and that queries can be expressed more compactly. In this paper we evaluate these theoretical advantages with user studies that compare SQLP to plain SQL as the baseline. The experiments show significant statistical evidence that SQLP indeed requires less time for understanding and authoring queries, with no loss in accuracy. Considering the positive results, we develop a method to reverse engineer legacy relational schemata into abstract relational ones

Mechanical thrombectomy: can it be safely delivered out of hours in the UK?

BACKGROUND: Mechanical thrombectomy was approved by NICE as a treatment for stroke in 2016. However, most of the evidence is from studies conducted during working hours. Only few centres in the UK perform thrombectomies out-of-hours. The Royal Stoke University Hospital (RSUH) has offered thrombectomies over 24 h (24/7) since 2010. The aim of this service review is to compare the outcomes for patients treated in regular working hours to those treated outside normal working hours within this unit. METHODS: This retrospective service analysis includes all patients treated with mechanical thrombectomy at RSUH since the start of the service in January 2010 to June 2019. Data on key demographics, timings, procedural complications, and long-term outcomes including death and disability at 90 days were collected. In-hours was defined as the time between 8:00-17:00 h, Monday to Friday; out-of-hours was defined as any time outside this period. RESULTS: In total, 516 mechanical thrombectomies were performed in this time period; data were available on 501 of these. Successful recanalization (TICI 2b/3) was achieved in 86% of patients. By 90 days 96 (19%) had died and 234 (47%) were functionally independent (modified Rankin Scale score ≤ 2). 211 (42%) of the procedures were performed in-hours and 290 (58%) out-of-hours. Door-to-CT and door-to-groin times were significantly longer out-of-hours than in-hours, but thrombectomy duration was significantly shorter. There were no significant differences in complications and short- and long-term outcomes. CONCLUSION: Mechanical thrombectomy was delivered safely and effectively 24/7 in this UK hospital, with no difference in clinical outcomes

Implementation of a population-based epidemiological rare disease registry: study protocol of the amyotrophic lateral sclerosis (ALS) - registry Swabia

BACKGROUND: The social and medical impact of rare diseases is increasingly recognized. Amyotrophic lateral sclerosis (ALS) is the most prevalent of the motor neuron diseases. It is characterized by rapidly progressive damage to the motor neurons with a survival of 2–5 years for the majority of patients. The objective of this work is to describe the study protocol and the implementation steps of the amyotrophic lateral sclerosis (ALS) registry Swabia, located in the South of Germany. METHODS/DESIGN: The ALS registry Swabia started in October 2010 with both, the retrospective (01.10.2008-30.09.2010) and prospective (from 01.10.2010) collection of ALS cases, in a target population of 8.6 million persons in Southern Germany. In addition, a population based case–control study was implemented based on the registry that also included the collection of various biological materials. Retrospectively, 420 patients (222 men and 198 women) were identified. Prospectively data of ALS patients were collected, of which about 70% agreed to participate in the population-based case–control study. All participants in the case–control study provided also a blood sample. The prospective part of the study is ongoing. DISCUSSION: The ALS registry Swabia has been implemented successfully. In rare diseases such as ALS, the collaboration of registries, the comparison with external samples and biorepositories will facilitate to identify risk factors and to further explore the potential underlying pathophysiological mechanisms

Female Chimpanzees Use Copulation Calls Flexibly to Prevent Social Competition

The adaptive function of copulation calls in female primates has been debated for years. One influential idea is that copulation calls are a sexually selected trait, which enables females to advertise their receptive state to males. Male-male competition ensues and females benefit by getting better mating partners and higher quality offspring. We analysed the copulation calling behaviour of wild female chimpanzees (Pan troglodytes schweinfurthii) at Budongo Forest, Uganda, but found no support for the male-male competition hypothesis. Hormone analysis showed that the calling behaviour of copulating females was unrelated to their fertile period and likelihood of conception. Instead, females called significantly more while with high-ranking males, but suppressed their calls if high-ranking females were nearby. Copulation calling may therefore be one potential strategy employed by female chimpanzees to advertise receptivity to high-ranked males, confuse paternity and secure future support from these socially important individuals. Competition between females can be dangerously high in wild chimpanzees, and our results indicate that females use their copulation calls strategically to minimise the risks associated with such competition

A thalamic reticular networking model of consciousness

<p>Abstract</p> <p>[Background]</p> <p>It is reasonable to consider the thalamus a primary candidate for the location of consciousness, given that the thalamus has been referred to as the gateway of nearly all sensory inputs to the corresponding cortical areas. Interestingly, in an early stage of brain development, communicative innervations between the dorsal thalamus and telencephalon must pass through the ventral thalamus, the major derivative of which is the thalamic reticular nucleus (TRN). The TRN occupies a striking control position in the brain, sending inhibitory axons back to the thalamus, roughly to the same region where they receive afferents.</p> <p>[Hypotheses]</p> <p>The present study hypothesizes that the TRN plays a pivotal role in dynamic attention by controlling thalamocortical synchronization. The TRN is thus viewed as a functional networking filter to regulate conscious perception, which is possibly embedded in thalamocortical networks. Based on the anatomical structures and connections, modality-specific sectors of the TRN and the thalamus appear to be responsible for modality-specific perceptual representation. Furthermore, the coarsely overlapped topographic maps of the TRN appear to be associated with cross-modal or unitary conscious awareness. Throughout the latticework structure of the TRN, conscious perception could be accomplished and elaborated through accumulating intercommunicative processing across the first-order input signal and the higher-order signals from its functionally associated cortices. As the higher-order relay signals run cumulatively through the relevant thalamocortical loops, conscious awareness becomes more refined and sophisticated.</p> <p>[Conclusions]</p> <p>I propose that the thalamocortical integrative communication across first- and higher-order information circuits and repeated feedback looping may account for our conscious awareness. This TRN-modulation hypothesis for conscious awareness provides a comprehensive rationale regarding previously reported psychological phenomena and neurological symptoms such as blindsight, neglect, the priming effect, the threshold/duration problem, and TRN-impairment resembling coma. This hypothesis can be tested by neurosurgical investigations of thalamocortical loops via the TRN, while simultaneously evaluating the degree to which conscious perception depends on the severity of impairment in a TRN-modulated network.</p