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In this paper, an energy-saving scheme in rotor field-orientated vector control is developed for induction motor drives. The energy-saving scheme minimizes copper and core losses in induction motors, which are equally applicable to induction generators. In efficiency optimization, an optimal stator angular velocity is uniquely obtained, and consequently, a corresponding optimal slip at any given rotor speed is determined. The challenge of determining a reference for rotor flux linkage that guarantees the minimal copper and core loss regime is overcome by developing a load torque observer loop. The torque observer is developed alongside a rotor speed observer for a sensorless speed operation. The observed mechanical torque is further used to enhance the outer-loop rotor speed control that generates an electromagnetic torque command used in building the reference for the inner-loop stator current control. The results obtained justified the effective operation of the torque and rotor speed observer, which consequently verified the effective minimal electrical loss regime at the optimal stator angular velocity and optimal rotor flux linkage. The results are further compared to results obtained from the equivalent induction machine drive on a finite-set model predictive control (FS-MPC) scheme with the same values of the optimal stator angular velocity and optimal rotor flux linkage. The developed efficiency-optimized vector control scheme gave lower ripples in developed electromagnetic torque and dampened overshoot better during step change in load torque.

Diverse control strategies for enhancing operations of isolated distribution grids are reviewed. Such distribution grids are called mini-grids or micro-grids, depending on their power flow capabilities. Robust control schemes identified in other climates for mini-grid and micro-grid operations are yet to be fully explored in the Nigerian electricity supply industry (NESI). Sustainable control strategies suitable for isolated distribution grids in the NESI predicate on capabilities for diverse objectives, such as energy conservation, affordability, efficient power throughput, and utilization, for enhanced resiliency and reliability. Consequently, the distributed control system in hierarchical layers is identified as a suitable choice for mini-grid operations in Nigeria because of its robustness in scalability and in energy conservation. However, the model predictive control (MPC) scheme is observed to be uniquely applicable in all of the hierarchical control layers. Therefore, a cascade-free MPC with improved robustness against sensitivity to system parameter variation is presented at the primary control layer for an H8 voltage source inverter (VSI) used for grid integration of the solar photovoltaic (PV) system. The H8 inverter gives more promising mitigation strategies against common-mode voltage and leakage current. Moreover, the control of DC link voltage for maximum power point tracking (MPPT) is achieved by the H8 inverter, thereby eliminating the need for a separate converter for MPPT. Thus, sustainability is achieved.

Abstract The Australian use of the term floodway refers to a trafficable transverse structure designed to facilitate the safe crossing of watercourses. Floodways are also commonly referred to as fords and causeways. This research explores areas of focus through experimental, numerical and survey methods to improve floodway resilience with regard to flood risk management. The industry‐based survey provides a dataset relating to user experiences, deduces the likeliness of floodways to sustain damage, defines several key focus areas, and reveals that the current risk levels are primarily managed without significant investigation into design. A floodway experimental and numerical simulation program was developed to investigate the lateral forces induced through debris impact using scaled models in a soil box and finite element analysis. Qualitatively, crack propagation and displacement correlated closely with the strain concentrations and displacements in the numerical simulation, with failure attributed to tensile strength being exceeded, followed by plastic strain development within the soil elements. It was concluded through this research that floodway failure during flood is complex and can be attributed to several different failure modes including concrete failure, yielding of adjoining soil material, and hydraulically via scour.

Type 2 diabetes is associated with insulin resistance, impaired insulin secretion and liver steatosis. Here the authors report a proof-of-concept study for small molecule SWELL1 modulators as a therapeutic approach to treat diabetes and associated liver steatosis by enhancing systemic insulin-sensitivity and insulin secretion in mice.

The use of batteries for diverse energy storage applications is increasing, primarily because of their high energy density, and lithium-ion batteries (LiBs) are of particular significance in this regard. However, designing estimators that are robust to compute the state of charge (SOC) of these batteries in the presence of disturbance signals arising from different battery types remains a challenge. Hence, this paper presents a hybrid estimator that combines the extended Kalman filter (EKF) and sliding mode observer (SMO) via a switching function and tracking closed loop to achieve the qualities of noise cancellation and disturbance rejection. Hybridization was carried out in such a way that the inactive observer tracks the output of the used observer, simultaneously feeding back a zero-sum signal to the input gain of the used observer. The results obtained show that noise filtering is preserved at a convergence time of .01 s. Also, the state of charge estimation interval improves greatly from a range of [1, .93] and [.94, .84] obtained from the extended Kalman filter and sliding mode observer, respectively, to a range of [1, 0], in spite of the added disturbance signals from a lithium–nickel (INR 18650) battery type.

Three phase induction motors (TPIM) are extensively used for various applications in the industry for driving cranes, hoists, lifts, rolling mills, cooling fans, textile operations, and so forth. TPIM are designed to operate on balanced three phase power supply, but sometimes three phase supply line voltages to which the TPIM is connected may be unbalanced. In this data article, the operational data of a TPIM operating under changing voltage scenarios is profiled to determine the variations in the magnitude of the operational parameters of the motor. The magnitude of each of the line voltages was separately varied from the balanced state (0% unbalance) until 5% voltage unbalance condition was achieved, in line with the recommendations and guidelines of the National Electrical Manufactures Association. The motor parameters; both mechanical and electrical, at various slip values were collected in six sets for the 0%, 1%, 2%, 3%, 4%, and 5% unbalance voltage conditions. Frequency distributions and statistical analysis were carried out to identify the data pattern and data variation trends among the parameters in the dataset. Keywords: Motor performance characteristics, Power quality, Three phase induction motor, Positive and negative sequence component, Voltage unbalance

Abstract Constrictive pericarditis is a disease where loss of pericardial elasticity and restriction of filling of the cardiac chambers occurs. It is most often seen as an associated symptom of heart failure. Pericardiectomy provides effective treatment for patients with symptomatic constrictive pericarditis, although high rates of morbidity and mortality are related to the procedure. We present a case with extensive calcification, massive caseous necrosis and an important impairment of right ventricular function successfully operated in our institution.

Threonine, like most amino acids, is traditionally noted for its role in protein synthesis. However, dietary threonine concentration required for the maximum performance of Japanese quails is yet to be determined, therefore, a study was conducted to determine the optimum threonine requirement of Japanese quail chicks in the tropical environment. A total of four hundred and fifty, two weeks old quail chicks (mixed sexes) were randomly allocated to five dietary treatments (0.67, 0.81, 0.95, 1.08 and 1.22 % total threonine) and replicated thrice in a completely randomized design (CRD). There were no significant differences (P>0.05) in average weight gain, average feed intake, feed conversion ratio and age at first lay of quails fed the dietary treatments. Weight of first egg laid was significantly (P0.05) similar for all treatments. There were significant differences (P0.05). It was concluded that the performance of birds were not influenced by the dietary treatments up to the highest dietary level of threonine studied (1.22%). Therefore, it is possible that the optimum dietary level of threonine may be above 1.22 %. Further studies will be necessary to establish higher doses of dietary threonine requirement of Japanese quails reared under tropical climatic environment.

The citizen creates the alien. The apparatus of citizenship establishes the criteria to determine who should be counted as undocumentable and therefore alien to lawful existence in this geographical territory. Detention centers extend the carceral imagination that subtends the modern state, which has claimed ownership of a particular land and has established a legal framework to criminalize and punish peoples who are categorized as threats to its vision for society. This paper tracks with Scriptural theologies that inform mechanisms of enslavement, the shadow side of citizenship. The United States is a project in social engineering, in population control, invested in registering and monitoring and relocating human life—all of which resonate with political trajectories outlined in biblical texts. The Scriptures are not salvific on their own terms. A liberative theology begins with a political commitment of solidarity. In this paper the detention center becomes a site from which to understand the carceral power that creates the world—a political landscape echoing with biblical theologies.

Acute pancreatitis is potentially fatal but treatment options are limited as disease pathogenesis is poorly understood. IL-33, a novel IL-1 cytokine family member, plays a role in various inflammatory conditions but its role in acute pancreatitis is not well understood. Specifically, whether pancreatic acinar cells produce IL-33 when stressed or respond to IL-33 stimulation, and whether IL-33 exacerbates acute pancreatic inflammation is unknown.In duct ligation-induced acute pancreatitis in mice and rats, we found that (a) IL-33 concentration was increased in the pancreas; (b) mast cells, which secrete and also respond to IL-33, showed degranulation in the pancreas and lung; (c) plasma histamine and pancreatic substance P concentrations were increased; and (d) pancreatic and pulmonary proinflammatory cytokine concentrations were increased. In isolated mouse pancreatic acinar cells, TNF-α stimulation increased IL-33 release while IL-33 stimulation increased proinflammatory cytokine release, both involving the ERK MAP kinase pathway; the flavonoid luteolin inhibited IL-33-stimulated IL-6 and CCL2/MCP-1 release. In mice without duct ligation, exogenous IL-33 administration induced pancreatic inflammation without mast cell degranulation or jejunal inflammation; pancreatic changes included multifocal edema and perivascular infiltration by neutrophils and some macrophages. ERK MAP kinase (but not p38 or JNK) and NF-kB subunit p65 were activated in the pancreas of mice receiving exogenous IL-33, and acinar cells isolated from the pancreas of these mice showed increased spontaneous cytokine release (IL-6, CXCL2/MIP-2α). Also, IL-33 activated ERK in human pancreatic tissue.As exogenous IL-33 does not induce jejunal inflammation in the same mice in which it induces pancreatic inflammation, we have discovered a potential role for an IL-33/acinar cell axis in the recruitment of neutrophils and macrophages and the exacerbation of acute pancreatic inflammation.IL-33 is induced in acute pancreatitis, activates acinar cell proinflammatory pathways and exacerbates acute pancreatic inflammation.

Assessment of physical activity in morbidly obese subjects is important especially in bariatric surgery. We examined the validity of Intelligent Device for Energy Expenditure and Activity (IDEEA) for measuring physical activity and sedentary behavior in morbidly obese women. Activity types, gait counts, and speed detected by the IDEEA monitor were compared to those reported by an observer. The IDEEA monitor detected activity types and gait counts with relatively high accuracy, although slightly lower in extremely obese women than in normal weight controls. The IDEEA monitor accurately estimated gait speeds in both groups. Since gait speed predicts energy expenditure more accurately than gait counts, it is of greater clinical relevance. Reliability of the IDEEA monitor was excellent. The IDEEA monitor is a valid instrument for measuring physical activity and sedentary behavior in extremely obese women, and therefore has potential applications in bariatric surgery both in preoperative evaluation and long-term follow-up.

Abstract Penetrating heart injuries present high mortality rates. Increasing rates of urban violence have contributed to a significant rise in the number of heart injuries by firearm projectiles. Such injuries are associated with the highest mortality rates among penetrating cardiac injuries and may involve one or more cardiac chambers. We present the case of a police officer who, in an approach to five robbers, suffered a transfixed cardiac injury by firearm with the projectile having been lodged inside the right ventricle. This patient was successfully operated, 65 days after the injury, at our institution.

Three hundred and sixty, six-week old Japanese quail (Coturnix coturnix japonica) hens were used to evaluate the effect of processed pigeon pea seed meal (PPSM) supplemented with enzyme (Vegpro) on egg quality characteristics of laying birds. The processing methods were soaking (24, 48 and 72 hours), fermentation (72 hours), boiling (60 minutes) and roasting (30 minutes). The birds were divided into eight groups of 45 per treatment each replicated three times with 15 birds per replicate in a completely randomized design. Eight experimental diets were formulated containing processed PPSM at 30 % of diet representing T1 (control), T2 (raw PPSM), T3 (soaked PPSM for 24 hours), T4 (soaked PPSM for 48 hours), T5 (soaked PPSM for 72 hours), T6 (soaked PPSM for 24 hours and fermented for 72 hours), T7 (boiling for 60 minutes) and T8 (roasted PPSM for 30 minutes) respectively. The experiment lasted for 20 weeks. Feed and water were provided ad libitum. The results showed that enzyme supplementation of diets containing raw and processed PPSM had no significant (p>0.05) effect on egg weight, egg height, egg diameter, egg shape index, egg shell thickness as well as albumen height, albumen diameter, albumen weight, yolk diameter, yolk weight, yolk index and haugh unit across the dietary treatments as these parameters were statistically similar. It was concluded that enzyme supplementation of raw and processed PPSM based diets had no significant effect on the egg quality characteristics of laying quail. [ABSTRACT FROM AUTHOR]