Flying path optimization in UAV-assisted IoT sensor networks

AbstractIn this paper, we present an optimal flying path for unmanned aerial vehicle-assisted internet of things sensor networks using a location aware multi-layer information map considering different utility functions based on the sensor density, energy consumption, flight time, and flying risk level. The overall weighted sum of multi-objective utility functions is maximized using the genetic algorithm. The simulation results verify that the optimum solution points can be obtained by adjusting the weights while satisfying the required constraints

Control of nacre biomineralization by Pif80 in pearl oyster

Molluscan nacre is a fascinating biomineral consisting of a highly organized calcium carbonate composite that provides unique fracture toughness and an iridescent color. Organisms elaborately control biomineralization using organic macromolecules. We propose the involvement of the matrix protein Pif80 from the pearl oyster Pinctada fucata in the development of the inorganic phase during nacre biomineralization, based on experiments using the recombinant form of Pif80. Through interactions with calcium ions, Pif80 participates in the formation of polymer-induced liquid precursor-like amorphous calcium carbonate granules and stabilizes these granules by forming calcium ion-induced coacervates. At the calcification site, the disruption of Pif80 coacervates destabilizes the amorphous mineral precursors, resulting in the growth of a crystalline structure. The redissolved Pif80 controls the growth of aragonite on the polysaccharide substrate, which contributes to the formation of polygonal tablet structure of nacre. Our findings provide insight into the use of organic macromolecules by living organisms in biomineralization.117Ysciescopu

Happiness among Pregnant Women: A Concept Analysis

PURPOSE: The purpose of this study was to analyze the concept of happiness among pregnant women. METHODS: Walker and Avant's method for concept analysis was used. RESULTS: The defining attributes of happiness among pregnant women were 1) period of pregnancy, 2) emotional dimension (positive affect), and 3) cognitive dimension(existence need-satisfaction, relatedness need-satisfaction, growth need-satisfaction). The antecedents of happiness among pregnant women were 1) intrapersonal characteristics, 2) reproductive history and related characteristics, 3) interpersonal relationship, and 4) external factors. The consequences included 1) pregnant women's well-being, 2) fetal well-being, 3) maternal well-being, and 4) child's happiness. CONCLUSION: Although further studies are required to refine the diverse attributes of the concept, the results of this study contribute to explaining happiness among pregnant women. In addition, the development of adequate interventions to increase prenatal happiness is needed

Optimization of isoprene production using a metabolically engineered Escherichia Coli

The volatile C5 hydrocarbon, isoprene is an important platform chemical, which has been used in the manufacture of synthetic rubber for tires and also has the potential for various other applications such as elastomers and adhesives. Moreover, isoprene is convertible to biofuel blend stocks such as C10 gasoline, C15 diesel, and jet fuels because of its higher energy content than other biofuels. Although isoprene is currently derived from petroleum, its sustainable supply has been suffered from price fluctuation of crude oil, high refining cost and energy consumption, and low recovery yield of pure isoprene. As an alternative, the biologically produced isoprene (bio-isoprene) has been developed rapidly for the last decade. Bio-isoprene is synthesized from dimethylallyl diphosphate (DMAPP), which is derived from mevalonate (MVA) pathway or the methylerythritol phosphate (MEP) pathway, by isoprene synthase. In this study, metabolic engineering for enhanced production of bio-isoprene was performed by deletion of relevant genes and optimization of culture condition. In comparison of isoprene production between E.coli DH5α and MG1655, lower isoprene production was observed in MG1655. The lower isoprene production in E. coli MG1655 was ascribed to the presence of recA gene which is absent in the DH5α strain. The deletion of recA gene in E.coli MG1655 allows higher isoprene production than E. coli DH5α. Moreover, the optimized expression of isoprene synthesis pathway with 0.03mM IPTG induction enhanced the isoprene production up to 2,850 mg/L. Overall, isoprene production through the optimization was improved by 28.5-fold compared to the initial production of MG1655 strain. Please click Additional Files below to see the full abstract

The effect of epidural administration of dexamethasone on postoperative pain: a randomized controlled study in radical subtotal gastrectomy

BACKGROUND: Epidurally administered dexamethasone may reduce the incidence and severity of postoperative pain. We investigated whether postoperative pain could be alleviated by preoperative or postoperative epidural dexamethasone administration in patients undergoing major abdominal surgery. METHODS: Ninety patients (age 30-77 with American Society of Anesthesiologists physical status I and II) undergoing radical subtotal gastrectomy were randomly allocated to three groups using computer generated randomization. In all groups, 10 ml of 0.25% ropivacaine was injected epidurally before the start and at the end of the operation. In Group I, a bolus ropivacaine epidural without dexamethasone was administered. In Group II, dexamethasone (5 mg) was added to the ropivacaine bolus epidural before the start of operation. In Group III, the same amount of dexamethasone was given with the ropivacaine epidural at the end of operation. Effort and resting VAS, the use of rescue analgesics and any complications noted during the procedure were evaluated. RESULTS: VAS and requirements of rescue analgesics were significantly lower in Groups II and III when compared to Group I. There were no difference in the incidence of nausea and vomiting between groups, but an itching sensation was frequent in Group III. CONCLUSIONS: The administration of 5 mg of dexamethasone epidurallly, before or after operation, could reduce the pain and analgesic requirement after radical subtotal gastrectomy.ope

Engineering de novo disulfide bond in bacterial alpha-type carbonic anhydrase for thermostable carbon sequestration

Exploiting carbonic anhydrase (CA), an enzyme that rapidly catalyzes carbon dioxide hydration, is an attractive biomimetic route for carbon sequestration due to its environmental compatibility and potential economic viability. However, the industrial applications of CA are strongly hampered by the unstable nature of enzymes. In this work, we introduced in silico designed, de novo disulfide bond in a bacterial alpha-type CA to enhance thermostability. Three variants were selected and expressed in Escherichia coli with an additional disulfide bridge. One of the variants showed great enhancement in terms of both kinetic and thermodynamic stabilities. This improvement could be attributed to the loss of conformational entropy of the unfolded state, showing increased rigidity. The variant showed an upward-shifted optimal temperature and appeared to be thermoactivated, which compensated for the lowered activity at 25 degrees C. Collectively, the variant constructed by the rapid and effective de novo disulfide engineering can be used as an efficient biocatalyst for carbon sequestration under high temperature conditions.1194Ysciescopu