Extra Amount Of Energy Research Articles

Nutrient sensing signaling and metabolic responses in shrimp Litopenaeus vannamei under acute ammonia stress

Ammonia is the primary environmental factor affecting the growth and health of crustaceans. It would induce oxidative stress and metabolic disorders. Extra amount of energy was demanded to maintain the physiological functions under ammonia stress. However, limited information was available on its effects on the main nutrient metabolism, as well as the nutrient sensing signaling pathways. In the present study, shrimp Litopenaeus vannamei were exposed to acute ammonia stress and injected with amino acid solution. The results showed that acute ammonia exposure resulted in lower free amino acid levels in hemolymph, incomplete activation of the mechanistic target of rapamycin (mTOR) signaling and cascaded less protein synthesis in muscle. It induced autophagy and activated the AMP-activated protein kinase (AMPK) pathway. Meanwhile, ammonia exposure enhanced glycolysis and lipogenesis, but inhibited lipolysis. The results characterized the integrated metabolic responses and nutrient signaling to ammonia stress. It provides critical clues to understand the growth performance and physiological responses in shrimp under ammonia stress.

Effects of Total Thermal Balance on the Thermal Energy Absorbed or Released by a High-Temperature Phase Change Material.

Front tracking and enthalpy methods used to study phase change processes are based on a local thermal energy balance at the liquid–solid interface where mass accommodation methods are also used to account for the density change during the phase transition. Recently, it has been shown that a local thermal balance at the interface does not reproduce the thermodynamic equilibrium in adiabatic systems. Total thermal balance through the entire liquid–solid system can predict the correct thermodynamic equilibrium values of melted (solidified) mass, system size, and interface position. In this work, total thermal balance is applied to systems with isothermal–adiabatic boundary conditions to estimate the sensible and latent heat stored (released) by and salts which are used as high-temperature phase change materials. Relative percent differences between the solutions obtained with a local thermal balance at the interface and a total thermal balance for the thermal energy absorbed or released by high-temperature phase change materials are obtained. According to the total thermal balance proposed, a correction to the liquid–solid interface dynamics is introduced, which accounts for an extra amount of energy absorbed or released during the phase transition. It is shown that melting or solidification rates are modified by using a total thermal balance through the entire system. Finally, the numerical and semi-analytical methods illustrate that volume changes and the fraction of melted (solidified) solid (liquid) estimated through a local thermal balance at the interface are not invariant in adiabatic systems. The invariance of numerical and semi-analytical solutions in adiabatic systems is significantly improved through the proposed model.

Proficient Techniques and Protocols for the Identification of Attacks in WSN: A Review

Objectives: In WSN (Wireless Sensor Network) attacks are the central concern. In this paper, we discuss various authentication techniques and protocols for detection of attacks in WSN). Our scope be situated on the way to take new authentication technique by analyzing various techniques and protocols for detection of attack. This technique solves the problems in existing techniques like micro Timed Sufficient Streaming Loss Tolerant Authentication protocol (μ TESLA), Secured Network Encryption Protocol (SNEP), Long Term Equity Anticipation Security (LEAP) ad node authentication all these techniques require an extra amount of energy for computational cost is very high. Analysis: Wireless Sensor Network (WSN) is used in various applications to monitor the sensitive environment. These applications have a high impact in human pursuit, battlefield monitoring and surround watching. After the deployment of the sector nodes at respective places the manual maintenance and monitoring is minimum for long interval of time due to these conditions it creates security problems at sensitive areas wherever the appliance is deployed. In this environment anyone will comes within the network to modify and hack the data. Due to this reason interference of the network also suffers from several constraints like low computation capability and restricted energy. These constraints conjointly build a security as a challenge in Wireless Sensor Network. In this paper we have various security protocols and techniques to beat these problems. Findings: By the limitations of resource we analysis and find the Zero Knowledge Protocol with Interlock Protocol for Sybil attack detection in WSN. These techniques having a less bandwidth, small computational power and less memory space.

New approach to exploit optimally the PV array output energy by maximizing the discharge rate of a directly-coupled photovoltaic water pumping system (DC/PVPS)

A directly-coupled photovoltaic water pumping system (DC/PVPS) is generally designed by considering the worst month conditions on lowest daylight-hours, the maximum monthly daily required water volume and tank to store the excess water. In case of absence of hydraulic storage (water tank) or it is not enough dimensioned, the extra amount of pumped water is lost or is not reasonably used, when the system is operated on full daylight-hour. Beside that the extra amount of energy, which might be produced by the PV generator, is not exploited, when the system is operated only during a specified period-time needed to satisfy the demand. Beyond the accurate design that satisfying the end-user, a new approach has been developed as target to exploit maximally the PV array energy production, by maximizing the discharge rate of the system. The methodology consists of approaching maximally the demanded energy to the supplied energy on full operating day. Based on the demand/supply energy condition, the approach has been developed, upon the PV array and the pump performance models. The issued approach predicts the maximum delivery capacity of the system on monthly daily water volumes versus the monthly daily averages of solar irradiation, previously recorded. Its efficacy has been investigated and discussed according to the estimated and experimental values of its linearity coefficient, following the characterization tests of a designed system, carried out at our pumping test facility in Ghardaia (Algeria). The new theoretically and experimentally obtained flow-rates fit well, except insignificant deviations. The demand and supply energy curves are approximately approachable. Compared to the previous required water volumes, the new predicted averages show an annual excess rate between 41% and 54%. This rate is expected to be extracted by an annual surplus energy rate between 29% and 36% of the total annual provided energy rate. The proposed approach may be a tool to investigate the maximal delivery capacity and to determine the corresponding maximal PV energy production to be exploited of such system, so that to select the best management at any case.

Diamond Networks With Bursty Traffic: Bounds on the Minimum Energy-Per-Bit

When data traffic in a wireless network is bursty, small amounts of data sporadically become available for transmission, at times that are unknown at the receivers, and an extra amount of energy must be spent at the transmitters to overcome this lack of synchronization between the network nodes. In practice, predefined header sequences are used with the purpose of synchronizing the different network nodes. However, in networks where relays must be used for communication, the overhead required for synchronizing the entire network may be very significant. In this paper, we study the fundamental limits of energy-efficient communication in an asynchronous diamond network with two relays. We formalize the notion of relay synchronization by saying that a relay is synchronized if the conditional entropy of the arrival time of the source message given the received signals at the relay is small. We show that the minimum energy-per-bit for bursty traffic in diamond networks is achieved with a coding scheme where each relay is either synchronized or not used at all. A consequence of this result is the derivation of a lower bound to the minimum energy-per-bit for bursty communication in diamond networks. This bound allows us to show that schemes that perform the tasks of synchronization and communication separately (i.e., with synchronization signals preceding the communication block) can achieve the minimum energy-per-bit to within a constant fraction that ranges from 2 in the synchronous case to 1 in the highly asynchronous regime.

Prospects of energy savings in the national meat processing factory

This investigation is conducted to examine potential opportunities of energy savings in the meat processing industry. It demonstrates that energy saving can be considered as a major factor to increase profit and competition within this sector. Detailed energy audits were carried out for meat processing equipment in the national factory. This work shows that there are large opportunities of savings which can be achieved by installing the economiser; using compressed air leakage points in the distribution air network, increasing the suction temperature of the high stage compressors as well as recovering of heat in blow down by preheating feed water which will save even more energy. It was found that the refrigeration systems consume more electricity compared to other departments. However, modification of the water pumping system will save an extra amount of energy. Finally, valuable recommendations to factory management are proposed and required additional research, analysis, and data collection are identified.

Observation-Based Estimates of Surface Cooling Inhibition by Heavy Rainfall under Tropical Cyclones

Abstract Tropical cyclones drive intense ocean vertical mixing that explains most of the surface cooling observed in their wake (the “cold wake”). In this paper, the authors investigate the influence of cyclonic rainfall on the cold wake at a global scale over the 2002–09 period. For each cyclone, the cold wake intensity and accumulated rainfall are obtained from satellite data and precyclone oceanic stratification from the Global Eddy-Permitting Ocean Reanalysis (GLORYS2). The impact of precipitation on the cold wake is estimated by assuming that cooling is entirely due to vertical mixing and that an extra amount of energy (corresponding to the energy used to mix the rain layer into the ocean) would be available for mixing the ocean column in the hypothetical case with no rain. The positive buoyancy flux of rainfall reduces the mixed layer depth after the cyclone passage, hence reducing cold water entrainment. The resulting reduction in cold wake amplitude is generally small (median of 0.07 K for a median 1 K cold wake) but not negligible (>19% for 10% of the cases). Despite similar cyclonic rainfall, the effect of rain on the cold wake is strongest in the Arabian Sea and weak in the Bay of Bengal. An analytical approach with a linearly stratified ocean allows attributing this difference to the presence of barrier layers in the Bay of Bengal. The authors also show that the cold wake is generally a “salty wake” because entrainment of subsurface saltier water overwhelms the dilution effect of rainfall. Finally, rainfall temperature has a negligible influence on the cold wake.

Nonadiabatic molecular dynamics of photoexcited ${\rm Li}_2^+{\rm Ne}_n$ Li 2+ Ne n clusters

We investigate the relaxation of photoexcited Li(2)(+) chromophores solvated in Ne(n) clusters (n = 2-22) by means of molecular dynamics with surface hopping. The simplicity of the electronic structure of these ideal systems is exploited to design an accurate and computationally efficient model. These systems present two series of conical intersections between the states correlated with the Li+Li(2s) and Li+Li(2p) dissociation limits of the Li(2)(+) molecule. Frank-Condon transition from the ground state to one of the three lowest excited states, hereafter indexed by ascending energy from 1 to 3, quickly drives the system toward the first series of conical intersections, which have a tremendous influence on the issue of the dynamics. The states 1 and 2, which originate in the Frank-Condon area from the degenerated nondissociative 1(2)Π(u) states of the bare Li(2)(+) molecule, relax mainly to Li+Li(2s) with a complete atomization of the clusters in the whole range of size n investigated here. The third state, which originates in the Frank-Condon area from the dissociative 1(2)Σ(u)(+) state of the bare Li(2)(+) molecule, exhibits a richer relaxation dynamics. Contrary to intuition, excitation into state 3 leads to less molecular dissociation, though the amount of energy deposited in the cluster by the excitation process is larger than for excitation into state 1 and 2. This extra amount of energy allows the system to reach the second series of conical intersections so that approximately 20% of the clusters are stabilized in the 2(2)Σ(g)(+) state potential well for cluster sizes n larger than 6.

Individual dietary intervention in patients with COPD during multidisciplinary rehabilitation

Dietary intervention studies in COPD patients often are short-term inpatient studies where a certain amount of extra energy is guaranteed. The aim of this study was to evaluate the effect of an 1 year individual multifaceted dietary intervention during multidisciplinary rehabilitation. Eighty-seven patients with severe COPD, not demanding oxygen therapy were included, 24 of them served as controls. A dietary history interview was performed at baseline and at study end. Dietary advice given were based on results from the dietary history and socio-economic status. The intervention group was divided into three parts; NW: normal weight (dietary advice given aiming to weight maintenance), OW: overweight (weight-reducing advice) and UW: underweight (dietary advise based on an energy- and protein-rich diet). Results: UW-group: Eighty-one per cent of the patients gained weight or kept a stable weight. OW-group: Fifty-seven per cent lost more than 2 kg. NW-group: Seventy-six per cent kept a stable weight or gained weight. Increased dietary intake from baseline was seen for energy, protein, carbohydrates and certain micronutrients (P<0.05) in the UW group. Six minutes walking distance increased by approximately 20 m in both NW (P<0.05) and UW patients. To conclude, slight, but uniform, indications of positive effects of dietary intervention during multidisciplinary rehabilitation was seen. Dietary intervention in underweight COPD patients might be a prerequisite for physical training.

Fusion Cross Section of Massive Nuclei by Fluctuation-Dissipation Dynamics

Fluctuation-dissipation dynamics is applied to the nearly mass-symmetric fusion reactions forming nuclei of Z> 80. We take into account the angular momentum of the system. The fusion cross section is calculated, and the hindrance of fusion is discussed. We estimate the amount of extra energy above the Coulomb barrier needed for fusion. In a fusion reaction with nearly symmetric projectile-target combination forming a compound nucleus with Z> 80 (or fissility larger than 0.65), additional kinetic energy above the incident Coulomb barrier is needed to realize the formation of a spherical compound nucleus. This supplementary energy was defined as the extraextra push energy EXX by Swiatecki 1) and systematic studies of this phenomenon, the so-called fusion hindrance, have been reported. 2) - 4) The origin of the necessity of the extra-extra push energy lies in the characteristics of the potential energy landscape in nuclear deformation parameter space. 5),6) As the system becomes heavier than Z around 80, the contact configuration comes to be located outside the ridge curve of the potential energy surface. Note that the fission saddle point is located on the ridge curve; it divides the deformation space into the mono-nucleus (fusion) region and di-nucleus (fission) region. This implies that the colliding nuclei must overcome the ridge to attain compact shapes, such as a sphere. Fusion hindrance has been investigated in the framework of the classical trajectory method 7) which describes fusion-fission dynamics in terms of the time evolution of the nuclear shape initially located at the contact configuration in the deformation space with a certain collective kinetic energy. To obtain information on EXX, the classical trajectory in a multi-dimensional deformation space has been calculated by Blocki et al. 7) taking into account the dissipative force stemming from the coupling between the collective and the single particle degrees of freedom. In their framework, the critical energy of the fusion reaction was obtained. There is no fusion event below the critical energy, while the trajectory always reaches the spherical region above the energy. The fluctuation of the trajectory which appears as the counterpart of the dissipative force was taken into account by Aguiar et al. 8) By the inclusion of fluctuations, it becomes possible to calculate the fusion probability; the trajectory becomes that of a Brownian particle and can thus be calculated using the Langevin equation. The aim of the present paper is to confirm the validity of the application of fluctuation-dissipation dynamics to the study of fusion of massive nuclei in the mass

The signal in total-body plethysmography: errors due to adiabatic-isothermic difference

Total-body plethysmography is a technique often employed in comparative physiology studies because it avoids excessive handling of the animals. The pressure signal obtained is generated by an increase in internal energy of the gas phase of the system. Currently, this increase in internal energy is ascribed to heating (and water vapour saturation) of the inspired gas. The standard equation for computing tidal-volume implies that only temperature and saturation differences can be responsible for generating the ventilation signal. In this study, we were able to demonstrate that the difference between the external process of the thoracic expansion, which is adiabatic, and the internal process of it, which is isothermic, is an important factor of internal energy change in the total-body plethysmography method. In other words, organic tissues transfer heat to the entering gas but also to the present gas, in a way that keeps internal expansion an isothermic process. This extra amount of energy was never taken into account before. Therefore, experiments using such a technique to measure tidal-volume should be done using isothermic chambers. Moreover, due to uncertainties of the complementary measurements (ambient and lung temperatures, ambient water vapour saturation) needed to compute tidal-volume using total-body plethysmography, a minimal temperature difference about 15°C between body and ambient should exist to keep uncertainties in tidal-volume values below 5%. However, this limit is not absolute, because it varies as a function of humidity and degree of uncertainty of the complementary measurements.