Energy Balance Mechanisms Research Articles

New performance-based plastic design and evaluation of blind bolted end-plate CFT composite frames with BRBs

The blind bolted end-plate connection to concrete-filled steel tube column (BECFT) composite frame with buckling-restrained braces (BRBs, BRB-BECFT) is a novel dual structure system that combines advantages of fast assembly ability for BECFT connections, great energy dissipation capacity for BRBs coupled with BECFT connections and superior gravity load-carrying capacity for concrete-filled steel tube (CFT) columns. Given authors’ prior experimental and theoretical studies on the BRB-BECFT structure system, and as no design method is as far introduced for this system with adequate accuracy, a new plastic design procedure based on the modified energy balance and global yield mechanism in the framework of performance-based plastic design method was proposed. The post-yielding stiffness and overall yield inter-story drift of the BRB-BECFT structure system was considered to improve the accuracy of the design base shear. Meanwhile, the BRB-BECFT structure system was decomposed into the BRB system and BECFT frame system to simplify the design process. Moreover, some formulae to avoid structural adverse yield mechanism were derived. The semi-rigid characteristic of BECFT connections was introduced into the structural global yield mechanism by work-energy principle to ensure the deformation consistency between inter-story drift and BECFT connection rotation. Finally, four prototype structures with 6, 9, 12 and, 20 stories were designed as examples to illustrate the effectiveness and robustness of the proposed design method. The results of nonlinear time-history analyses showed that the designed structures successfully achieved the pre-selected performance objectives in terms of the inter-story drift, residual drift, BECFT connection rotation, and BRB ductility demands.

Regulatory and Metabolic Interactions of Carbohydrates and Lipids in Diabetes and Obesity

This paper attempts to review available pertinent scientific and medical literature that the current global epidemic of obesity and diabetes has increased simultaneously or contemporaneously with adverse metabolic events. There is widespread established evidence that the type of carbohydrate consumed is important in the development or prevention of insulin resistance, obesity, and the metabolic syndrome. There is scarcity of published data on the combined effects of interactions between micronutrients, carbohydrates and lipids. However, there are extensive data supporting the benefits of the effects of both carbohydrates and lipids on various mechanisms of energy balance and diseases. Adequate measure is necessary to control carbohydrate-lipid interactions as they impact on obesity and diabetes.

Photorespiration is the major alternative electron sink under high light in alpine evergreen sclerophyllous Rhododendron species

Owing to the high leaf mass per area, alpine evergreen sclerophyllous Rhododendron have low values of mesophyll conductance (gm). The resulting low chloroplast CO2 concentration aggravates photorespiration, which requires a higher ATP/NADPH ratio. However, the significance of photorespiration and underlying mechanisms of energy balance in these species are little known. In this study, eight alpine evergreen sclerophyllous Rhododendron species grown in a common garden were tested for their gm, electron flow to photorespiration, and energy balancing. Under saturating light, gm was the most limiting factor for net photosynthesis (AN) in all species, and the species differences in AN were primarily driven by gm rather than stomatal conductance. The total electron flow through photosystem II (ETRII) nearly equaled the electron transport required for Rubisco carboxylation and oxygenation. Furthermore, blocking electron flow to photosystem I with appropriate inhibitors showed that electron flow to plastic terminal oxidase was not observed. As a result, these studied species showed little alternative electron flow mediated by water-water cycle or plastic terminal oxidase. By comparison, the ratio of electron transport consumed by photorespiration to ETRII (JPR/ETRII), ranging from 43%∼55%, was negatively correlated to AN and gm. Furthermore, the increased ATP production required by enhanced photorespiration was regulated by cyclic electron flow around photosystem I. These results indicate that photorespiration is the major electron sink for dissipation of excess excitation energy in the alpine evergreen sclerophyllous Rhododendron species. The coordination of gm, photorespiration and cyclic electron flow is important for sustaining leaf photosynthesis.

A Single-Phase Five-Branch Direct AC–AC Modular Multilevel Converter for Railway Power Conditioning

This paper introduces a single-phase five-branch direct ac-ac modular multilevel converter (MMC) with the capability of equal frequency conversion for railway power conditioning applications. By analyzing the branch energy balance mechanism, the basic operating principle of the proposed MMC is clarified and the control strategy is also proposed. Comparisons between the proposed MMC and the traditional modular multilevel matrix converter (MMMC) on branch voltage and current ratings as well as capacitor dimension requirements are also presented. The effectiveness of the proposed topology and the control strategy is validated on a down-scaled prototype. Both the theoretical analyses and the experimental results reveal that for compensating low power factor traction loads in Scott transformer-based railway power systems, the proposed MMC has decreased branch current stresses and capacitor voltage fluctuations compared to the traditional MMMC, and the required total submodule numbers of these two MMCs are comparable.

Absence of photosynthetic state transitions in alien chloroplasts

Main conclusionThe absence of state transitions in a Nt(Hn) cybrid is due to a cleavage of the threonine residue from the misprocessed N-terminus of the LHCII polypeptides.The cooperation between the nucleus and chloroplast genomes is essential for plant photosynthetic fitness. The rapid and specific interactions between nucleus-encoded and chloroplast-encoded proteins are under intense investigation with potential for applications in agriculture and renewable energy technology. Here, we present a novel model for photosynthesis research in which alien henbane (Hyoscyamus niger) chloroplasts function on the nuclear background of a tobacco (Nicotiana tabacum). The result of this coupling is a cytoplasmic hybrid (cybrid) with inhibited state transitions—a mechanism responsible for balancing energy absorption between photosystems. Protein analysis showed differences in the LHCII composition of the cybrid plants. SDS-PAGE analysis revealed a novel banding pattern in the cybrids with at least one additional ‘LHCII’ band compared to the wild-type parental species. Proteomic work suggested that the N-terminus of at least some of the cybrid Lhcb proteins was missing. These findings provide a mechanistic explanation for the lack of state transitions—the N-terminal truncation of the Lhcb proteins in the cybrid included the threonine residue that is phosphorylated/dephosphorylated in order to trigger state transitions and therefore crucial energy balancing mechanism in plants.

Modeling on plasma energy balance and transfer in a hollow cathode

The hollow cathode lifetime is largely determined by the dissipation of the active emitter material and the ion-induced sputtering erosion. These two critical factors are involved in the physical mechanisms of the internal energy balance and plasma energy transfer to the cathode walls. Based on particle kinetic dynamics and behaviour statistics, a plasma energy balance and transfer model for the hollow cathode was established. The hollow cathode discharge process and steady-state plasma parameters were investigated by employing the self-consistent full particle-in-cell approach combined with Monte Carlo collisions. Relevant 2D numerical simulations for the partially ionized gas in hollow cathode were performed. The calculated parameters of the plasma energy balance and transfer model mainly include the plasma potential, plasma density, particle velocity, resistivity distribution, ohmic heating and electric-field work. In the full particle-in-cell code, the hollow cathode operated at a planar diode regime with a discharge current of 10.0 A and a gas flow rate of 3.5 sccm. The simulation results show that the electric field power is 85.9 W in the insert region, 37.5 W in the orifice region and 147.4 W in the plume region, respectively. The work performed by the electron pressure gradient in the insert region, orifice region and plume region is in the ratio of about 1.2:1:5.3. The ion kinetic-energy flux is negligible compared with the electron kinetic-energy transfer.

Negative-Sequence Second-Order Circulating Current Injection for Hybrid MMC Under Over-Modulation Conditions

Due to the presence of full-bridge submodules (FBSMs), hybrid modular multilevel converters (HMMCs) consisting of FBSMs and half-bridge submodules (HBSMs) can work under the over-modulation conditions, which means that half of the dc voltage is less than the magnitude of the ac voltage. However, because of the different charging and discharging characteristics of FBSMs and HBSMs under over-modulation conditions, capacitor voltages imbalance may occur if the modulation index exceeds a specific limit. To address this issue, this article first investigates the principles of HMMCs and the energy balance mechanism between the two types of submodules. Based on the theoretical analysis, a negative-sequence second-order circulating current injection method is proposed to keep the capacitor voltage balanced under over-modulation conditions. Finally, the proposed method is validated by both simulation and experimental results.

Prototype and model of solar driven desalination plant in arid environment

Water shortage and salinity are crucial factors affecting plant growth in arid and semi-arid regions, where irrigation water shortage and capillary rise from shallow saline water tables are often encountered. The objectives of this study are to construct a prototype of solar driven desalination plant in an arid area of Jordan Rift Valley, to develop a mathematical model predicting thermal dynamics in the prototype, to calibrate model parameters with measured physical parameters, and to discuss the performance of the prototype as well as its applicability to other areas under different environment. Results of measurement and numerical simulation show that the model is capable to reproduce the thermal dynamics of the desalination plant and to predict dew yield. Overall, the developed model provides a sound basis for describing and explaining the mass and energy balance mechanisms in the developed desalination plant. This study offers also a useful tool for analysis and assessment of the dew yield and thermal dynamics of such a desalination plant in general. Using the constructed prototype, performance analysis based on crop cultivation is ongoing.

Intensity of Agricultural Workload and the Seasonality of Births in Italy.

According to "the energy balance mechanism" theory, female ovarian function is strongly hindered by even a modest negative energy balance (the difference between calorie intake and calorie consumption). Agriculture-based economies were characterized by periods of extremely intense workload (especially in summer when grain was harvested) without sufficient nutrition. We analyze the role of the intensity of agricultural workload (proxied by marriage seasonality) on seasonal oscillations in births. Using data at the regional level, from Italian Unification to the eve of the World War I, we find some empirical support for the energy balance theory. In particular, we find the strength of the relationship between marriage seasonality and birth seasonality to be lower in the more developed Northern part of the Italian country, in which some signs of industrialization had already been present.

A distributed, multi‐hop, adaptive, tree‐based energy‐balanced routing approach

SummaryTo accomplish the primary objective of data sensing and collection of wireless sensor networks (WSN), the design of an energy efficient routing algorithm is very important. However, the energy constrained sensing nodes along with the intrinsic properties of the (WSN) environment makes the routing a challenging task. To overcome this routing dilemma, an improved distributed, multi‐hop, adaptive, tree‐based energy‐balanced (DMATEB) routing scheme is proposed in this paper. In this scheme, a relay node is selected in view of minimum distance and high energy from a current sensing node. Further, the parent node is chosen among the selected relay nodes on the basis of high residual energy and less power consumption with due consideration of its associated child nodes. As each sensing node itself selects its parent among the available alternatives, the proposed scheme offers a distributive and adaptive approach. Moreover, the proposed system does not overload any selected parent of a particular branch as it starts acting as a child whenever its energy lowers among the other available relay nodes. This leads to uniform energy utilization of nodes that offers a better energy balance mechanism and improves the network lifespan by 20% to 30% as compared with its predecessors.

"How Foraging Works": Let's not forget the physiological mechanisms of energy balance.

Anselme & Güntürkün propose a novel mechanism to explain the increase in foraging motivation when experiencing an unpredictable food supply. However, the physiological mechanisms that maintain energy homeostasis already control foraging intensity in response to changes in energy balance. Therefore, unpredictability may just be one of many factors that feeds into the same dopaminergic "wanting" system to control foraging intensity.

An overview of energy and metabolic regulation.

The physiology and behaviors related to energy balance are monitored by the nervous and humoral systems. Because of the difficulty in treating diabetes and obesity, elucidating the energy balance mechanism and identifying critical targets for treatment are important research goals. Therefore, the purpose of this article is to describe energy regulation by the central nervous system (CNS) and peripheral humoral pathway. Homeostasis and rewarding are the basis of CNS regulation. Anorexigenic or orexigenic effects reflect the activities of the POMC/CART or NPY/AgRP neurons within the hypothalamus. Neurotransmitters have roles in food intake, and responsive brain nuclei have different functions related to food intake, glucose monitoring, reward processing. Peripheral gut- or adipose-derived hormones are the major source of peripheral humoral regulation systems. Nutrients or metabolites and gut microbiota affect metabolism via a discrete pathway. We also review the role of peripheral organs, the liver, adipose tissue, and skeletal muscle in peripheral regulation. We discuss these topics and how the body regulates metabolism.

New Approaches for Weight Loss: Experiments Using Animal Models

The number of people who are overweight and obese are continuously increasing both in the adult and adolescent populations. Coinciding with this is the increased prevalence of health problems such as type 2 diabetes (T2D). Bariatric surgery is the only proven long-term treatment of obesity and may induce remission of T2D, although the underlying mechanisms are unknown. The translational studies presented here might provide insight on the mechanism of steady-state energy balance of the obese phenotype using a special time-restricted feeding regimen for weight loss during the steady-state energy balance; mechanism by vagal blocking therapy (vBLoc® therapy) as a new treatment for obesity; and possible mechanism behind the remission of T2D following gastric bypass surgery.

Food Cues and Obesity: Overpowering Hormones and Energy Balance Regulation.

In the modern obesogenic environment, food cues play a crucial role in the development of obesity by disrupting hormone and energy balance mechanisms. Thus, it is critical to understand the neurobiology of feeding behaviors and obesity in the context of ubiquitous food cues. The current paper reviews the physiology of feeding, hormonal regulation of energy balance, and food cue responses and discusses their contributions to obesity. Food cues have strong impact on human physiology. Obese individuals have altered food cue-elicited responses in the brain and periphery, overpowering hormone and energy balance regulation. Disrupted homeostasis during food cue exposure leads to continued food intake, unsuccessful weight management, and poor treatment outcomes, which further contributes to obesity epidemic. Findings from the review emphasize the crucial role of food cues in obesity epidemic, which necessitates multidimensional approaches to the prevention and treatment of obesity, including psychosocial interventions to reduce food cue reactivity, along with conventional treatment.

A Rendezvous Mechanism for Energy Balance and Link Quality in WSNs

Quorum System is a good method to assist the design of sensors of the wake-up scheduling mechanism. However, there are some problems about idle rendezvous and poor link quality when the sensor performs a sensing task according to the Quorum System. In order to improve the efficiency of the sensors and reduce energy consumption, a new rendezvous mechanism is proposed. The use of energy and the link quality between sensors are considered from a global perspective. It can not only ensure the rendezvous opportunity among sensors, but also balance the residual energy of the sensors, so it can improve the energy-saving efficiency of traditional Quorum System. According to the simulation, compared with the traditional Quorum System scheduling mechanism, the rendezvous mechanism proposed in this paper can effectively reduce the number of time-slots when the sensor is idle. Moreover, it also realizes the balance of the residual energy of the sensor and the link quality, which prolongs the life cycle of the wireless sensor network and improves the communication quality.

Intermittent fasting, energy balance and associated health outcomes in adults: study protocol for a randomised controlled trial

BackgroundPrior studies have shown that intermittent fasting is capable of producing improvements in body weight and fasted health markers. However, the extent to which intermittent fasting incurs compensatory changes in the components of energy balance and its impact on postprandial metabolism are yet to be ascertained.MethodsA total of 30–36 lean participants and 30–36 overweight/obese participants will be recruited to provide two separate study groups who will undergo the same protocol. Following an initial assessment of basic anthropometry and key health markers, measurements of habitual energy intake (weighed food and fluid intake) and physical activity energy expenditure (combined heart rate and accelerometry) will be obtained over 4 weeks under conditions of energy balance. Participants will then be randomly allocated to one of three experimental conditions for 20 days, namely (1) daily calorie restriction (reduce habitual daily energy intake by 25%), (2) intermittent fasting with calorie restriction (alternate between 24-hour periods of fasting and feeding to 150% of habitual daily energy intake), (3) intermittent fasting without calorie restriction (alternate between 24-hour periods of fasting and feeding to 200% of habitual daily energy intake). In addition to continued monitoring of energy intake and physical activity during the intervention, participants will report for laboratory-based assessments of various metabolic parameters both before and after the intervention. Specifically, fasting and postprandial measurements of resting metabolic rate, substrate oxidation, appetite, food preference, and plasma concentrations of key metabolites and hormones will be made, in addition to subcutaneous abdominal adipose tissue biopsies in the fasted state and an assessment of body composition via dual-energy x-ray absorptiometry.DiscussionComparing observed changes in these measures across the three intervention arms in each group will establish the impact of intermittent fasting on postprandial metabolism and the components of energy balance in both lean and overweight/obese populations. Furthermore, this will be benchmarked against current nutritional interventions for weight management and the relative contributions of negative energy balance and fasting-dependent mechanisms in inducing any observed effects will be elucidated.Trial registrationTrial retrospectively registered at clinicaltrials.gov under reference number NCT02498002 (version: IMF-02, date: July 6, 2015).

DC offset minimisation of three‐phase multilevel inverter configuration under fault and DC link voltage unbalance conditions

In recent days, multilevel inverters are quite popular in the photovoltaic system to improve the power quality. One of the popular multilevel inverters for medium power applications is neutral point clamping inverter. However, with the limited number of switching combinations, energy balancing and fault-tolerant operation is a major issue. The absence of energy balance mechanism may lead to unequal charge and discharge patterns in the batteries used in off-grid applications, which in turn results in the un-equal voltage at the batteries terminals. The difference in voltage between the sources can introduce the DC voltage offset at AC output, which causes serious problems when fed to the transformers or inductive loads like the induction motor. To address this problem, a five-level inverter is proposed which is capable of energy balancing between the two DC sources, minimising the DC voltage offset and able to operate in some fault-tolerant conditions. At the same time, this topology uses less number of switches as compared to conventional three-phase five-level inverters. The proposed topology is developed by combining conventional two-level and three-level inverters. The topology is verified by simulation using Matlab Simulink and tested on a laboratory prototype. The control algorithm for prototype is implemented with the help of Xilinx SPARTAN-6 (XC6SLX9) FPGA board.

Natural Dietary Products and Their Effects on Appetite Control.

Natural dietary products have been thoroughly studied for their effects of antiadipogenesis to prevent and treat obesity for decades. Nevertheless, in the past few years appetite control for the treatment of obesity has attracted much attention as a new target. Homeostatic control of energy intake involves a complex system that conveys peripheral signals to the central nervous system where multiple signals are integrated and then provide feedback to regulate satiation. This perspective aims at elucidating the neuronal mechanisms of food intake and energy balance as well as providing an alternative pathway of controlling weight using natural dietary products.

Seasonal fluctuations in body weight during growth of Thoroughbred racehorses during their athletic career

BackgroundDomesticated horses adapt to environmental conditions through seasonal fluctuations in their metabolic rate. The seasonal change of metabolic rates of domesticated horses in pastures is documented. However, there are few investigations on seasonal body weight change of domesticated horses housed in stables, which are provided constant energy intake throughout the year. Both seasonal changes and gain in body weight of racehorses during their athletic career is known to a lesser extent because their body weight are not measured in most countries. Here, we used a seasonal-trend decomposition method to conduct a time series analysis of body weight of Thoroughbred racehorses participating in flat races held by the Japan Racing Association from 1 January 2002 to 31 December 2014.ResultsWe acquired 640,431 body weight measurements for race starts and included 632,540 of these in the time series analysis. Based on seasonal component analysis, the body weight of male and gelding horses peaked in autumn and winter and reached its nadir in summer. In contrast, the body weight of female horses peaked in autumn and reached the nadir in spring. Based on trend component analysis, most of the increase in body weight was observed when all sexes approached 5 years of age. The slope of the body weight gain was smaller after that, and an approximately 30 kg gain was observed during their careers.ConclusionThese results indicate that the body weight of a Thoroughbred racehorse fluctuates seasonally, and that there may be sex differences in energy balance mechanisms. Moreover, the present results suggest that the physiological development of Thoroughbred racehorses is completed just before they reach 5 years of age.

Features of the Energy Balance and Fragmentation Mechanisms at Spontaneous Failure of Class I and Class II Rocks

Practically, all types of rockbursts are accompanied by release of seismic energy, rock bulking (due to fracturing and fragmentation), and ejection of fragmented rocks in the opening. Principles of the energy redistribution during rockbursts in some regards are comparable with principles taking place at spontaneous failure of rock specimens under compression in loading systems. In both cases, the total potential elastic energy accumulated in the failing material and in the loading system (or surrounding rock mass) is converted into such components of dynamic energy as rupture energy, seismic energy (or energy of oscillation of the loading system due to dynamic energy release), and kinetic energy of flying fragments of the failed material. It is known that spontaneous failure takes place at the post-peak failure stage and is determined by the ratio between stiffness of the loading system and stiffness (or brittleness) of the failing material. However, principles of the energy redistribution between different components of the energy balance are still unclear. The paper discusses results of laboratory experiments conducted on rock specimens of different brittleness (including Class I and Class II) that were loaded in testing machines of different loading stiffness. The most brittle of the tested specimens are represented by quartzite and glass, and the less brittle by salt. The loading stiffness of testing machines used in experiments was variable within three decimal orders of magnitude. The specific variations of the dynamic energy balance depending on rock brittleness and loading stiffness were established. The role of each portion of elastic energy stemming from the specimen and from the loading system in determining the dynamic energy balance and fragmentation mechanisms operating at spontaneous failure is analysed. The results obtained contribute to the understanding of dynamic processes taking place during rockbursts.