A bio-inspired host-parasite structure for broadband vibration energy harvesting from low-frequency random sources

Energy harvesting for low-power sensing has drawn great attention, but still faces challenges in harnessing broadband random motions. Inspired by the parasitic relationship in plants, a host-parasite vibration harvester is designed to scavenge random low-frequency vibrations by incorporating bi-stability and frequency up-conversion within such a design. A hosting beam is formed in a buckled condition by clamping it at both ends and applying an axial compression load. Two parasitic piezoelectric beams are fixed at the center of the hosting beam and plucked at the free ends by two plectra on the hosting beam, while it oscillates in an inter-well mode. The low-frequency hosting beam oscillation is converted to high-frequency parasitic beam's vibration at resonance due to the plucking effect, allowing the harvester to convert the broadband low-frequency motion into electricity effectively. The electromechanical dynamics are modeled and the design is validated experimentally. The harvester is capable of harnessing low-frequency random vibration (0.0018 g2/Hz @ 5–400 Hz) over a wide bandwidth. More than 1 mJ energy was collected over 100 s under this pseudorandom vibration. Energy harvesting has been recognized as one of the key enablers for self-powered sensing applications in the era of Internet of things.1–4 However, enhancing the energy harvesting effectiveness requires significant efforts, especially for different energy sources under various conditions, such as low-frequency human motion,5,6 random aircraft vibrations7 or ocean waves.8 Harnessing a random, broadband and low-frequency kinetic energy is one of the key challenges, and different mechanisms have been developed to enhance the conversion performance. Nonlinear dynamics are one major consideration to enhance the operation bandwidth.9–11 Different harvesters have been developed with monostable,12–14 bistable15–17 and multistable behaviors.18–20 The aim is to alter harvesters' potential shape by applying preloads using magnetic forces21–23 or displacement constraints.24,25 A good example of a bistable harvester using displacement constraints is a device designed for harvesting energy from the passing traffic and pedestrians.26 A scissor-like structure was adopted to transfer the vertical passing weight to a horizontal axial force for buckling and excitation. In addition to nonlinearity, frequency up-conversion is another mechanism that is often employed in harvesting low-frequency motions, especially human motion.27–29 This mechanism uses a beam plucking effect to convert the low-frequency plucking motion into high-frequency transducers' vibration, in which the transducers normally operate at resonance after each plucking. Direct impact30 and magnetic plucking31 are typical methods to achieve the plucking motion and activate the transducers. In a recent work, Halim and Park developed an impact-driven harvester for harvesting the human-limb motion.32 A metal ball was designed to impact a flexible side-wall where a piezoelectric beam is fixed. The impact motion excited the beam, and the low-frequency limb motion was up-converted to a high-frequency beam vibration. The parasitic relationship is a well-known phenomenon in nature. Figure 1(a) provides a good example in plants, where a dodder is reliant on a host plant. In terms of motion and dynamics, the parasitic plant intertwines with the hosting plant and moves along with the host; however, due to the freedom of its own structure, the parasitic plant exhibits more complex dynamics even under simple hosting plant's motions, such as airflow-induced low-frequency vibration

Population structure of sea cucumber Holothuria parva using 16S mitochondrial rRNA gene sequences in the northern coast of Persian Gulf

In order to investigate the population structure species of sea cucumber Holothuria parva in the two regions Bostaneh Port and Dayer Port, 16S rRNA gene sequencing method was used. In total, 417 nucleotide loci were determined, after investigating in the NCBI database, sequences were consistent with 16S rRNA gene and samples were verified to belong to the species H. parva. In total four haplotypes were identified, one of which was common in both regions. Bostaneh Port had 3 haplotypes and Dayer Port had 2 haplotypes. Haplotype diversity was estimated to be 83 percent in Bostaneh Port and 50 percent in Dayer Port. Estimated Nucleotide diversity in Bostaneh and Dayer Ports were 0.007 and 0.002 respectively. Low genetic differentiation (Fst=0.000), divergences rate (Dxy= 0.0048) and high gene flow (Nm=1874) between the two regions were estimated. Based on this study Bostaneh and Dayer Port samples have probably diverged from an identical population since a high gene flow and low differentiation is observed among them. There is also a common haplotype, suggesting a common ancestor of H. parva in two regions

Assay of genetic diversity of cuttlefish (Sepia pharaonis; Ehrenberg, 1831) populations using microsatellite markers in Bandar Abbas and Bushehr regions

In this present study genetic diversity of cuttlefish (Sepia pharaonis) populations were investigated using microsatellite markers. Total 51 samples were collected from Bandarabass and Bushehr regions. Tissue sample of arm tips (tentacle) were preserved in 96% ethanol alcohol until using in biotechnology laboratory of Khorramshahr University of Marine Science and Technology. Genomic DNA was extracted with CTAB method. The quality and quantity of extracted DNA was assessed by 1% agarose gel electrophoresis and spectrophotometry, respectively. Polymerase chain reaction conducted with 6 pairs of microsatellite primers. PCR products were electrophoresed on 8% polyacrylamide gel and stained with silver nitrate. These primers were shown 4 pairs of polymorph and 2 pairs of monomorp. Allele Sizes were measured in populations then genetic parameter were calculated using Arlequin and Gen Alex Programs and phylogenetic relationship was determinated and drawn using TFPGA Program. Result obtained showed genetic distance and resemblance distance is 0.282 and 0.754, respectively and Weak but significant genetic differentiation was present 0.031 between of populations

Generalized conductance sum rule in atomic break junctions

When an atomic-size break junction is mechanically stretched, the total conductance of the contact remains approximately constant over a wide range of elongations, although at the same time the transmissions of the individual channels (valence orbitals of the junction atom) undergo strong variations. We propose a microscopic explanation of this phenomenon, based on Coulomb correlation effects between electrons in valence orbitals of the junction atom. The resulting approximate conductance quantization is closely related to the Friedel sum rule.Comment: 4 pages, 1 figure, appears in Proceedings of the NATO Advanced Research Workshop ``Size dependent magnetic scattering'', Pecs, Hungary, May 28 - June 1, 200

Cloning of the GH gene from the beluga sturgeon (Huso huso) into a lentivial & none viral constructs and it’s expression in HEK cell lines

Caviar-producing fish with their economically valuable product are important in fisheries. The cDNA growth hormone (GH) of Beluga sturgeon (Huso huso) was constructed using total RNA from pituitary glands. To construct the recombinant and active lentiviruses carring GH gene, this DNA sequence was inserted into the cloning vector pTZ57R/T and subsequently cutted from pTZ57R/T by endonuclease enzyme and incorporated into lentivirus vector pNL-EGFP/CMV-WPRE on upstream of an IRES cassette. We also insert a reporter EGFP gene downstream of IRES so transfection and transduction steps can be traced. Using this vector plus virus packaging and envelope vectors, HEK293T cells was co-transfected by DNA-Lipofectamine complexes method. Cell supernatant full of virions was collected 48 hours later and concentrated using Amicon columns to obtain a high-titer virus stock. Nearly 1/5 of this stock was applied to a new batch of cultured HEK-293T. After 72h expression of EGFP gene was detected and the cells was collected for further analysis. Total RNA of these transduced cells was extracted and GH mRNA expression was revealed by RT-PCR. Results showed that, lentiviral vectors (LV) as a gene transfer system provide efficient delivery, integration and long-term expression by establishing a stable provirus in target cells and could be important tool in aquaculture and fisheries biotechnology research to increase the growth rate of farmed fish by transferring growth hormone (GH) transgenes into fish

Cloning of the GH gene from the beluga sturgeon (Huso huso) into a lentivial & none viral constructs and its expression in HEK cell lines

Caviar-producing fish with their economically valuable product are important in fisheries. The cDNA growth hormone (GH) of Beluga sturgeon (Huso huso) was constructed using total RNA from pituitary glands. To construct the recombinant and active lentiviruses carring GH gene, this DNA sequence was inserted into the cloning vector pTZ57R/T and subsequently cutted from pTZ57R/T by endonuclease enzyme and incorporated into lentivirus vector pNL-EGFP/CMV-WPRE on upstream of an IRES cassette. We also insert a reporter EGFP gene downstream of IRES so transfection and transduction steps can be traced. Using this vector plus virus packaging and envelope vectors, HEK293T cells was co-transfected by DNA-Lipofectamine complexes method. Cell supernatant full of virions was collected 48 hours later and concentrated using Amicon columns to obtain a high-titer virus stock. Nearly 1/5 of this stock was applied to a new batch of cultured HEK-293T. After 72h expression of EGFP gene was detected and the cells was collected for further analysis. Total RNA of these transduced cells was extracted and GH mRNA expression was revealed by RT-PCR. Results showed that, lentiviral vectors (LV) as a gene transfer system provide efficient delivery, integration and long-term expression by establishing a stable provirus in target cells and could be important tool in aquaculture and fisheries biotechnology research to increase the growth rate of farmed fish by transferring growth hormone (GH) transgenes into fish

Prediction of marbofloxacin dosage for the pig pneumonia pathogens Actinobacillus pleuropneumoniae and Pasteurella multocida by pharmacokinetic/pharmacodynamic modelling

PK/PD integration data. (DOCX 7 kb

Lived Experience of Caregivers of Family-Centered Care in the Neonatal Intensive Care Unit: “Evocation of Being at Home

Background: In recent decades, family-centered care (FCC) has come to be known, accepted, and reported as the best care strategy for admitted children and their families. However, in spite of the increasing application of this approach, the experiences of the caregivers have not yet been studied. Objectives: The present study aimed at the description and interpretation of the FCC experience in two neonatal intensive care units (NICU) at Shiraz University of Medical Sciences. Methods: This study was conducted through the hermeneutic phenomenological approach. Semi-structured interviews were conducted with 17 professional and familial caregivers, and their interactions were observed in three work shifts. The interviews were audiotaped and transcribed verbatim. After observations, field notes were also written. Finally, the data were analyzed through van Manen’s methodology. Results: One of the essential themes that emerged in this study was the “evocation of being at home” among familial and even professional caregivers. This theme had three subthemes: i.e., “meta-family interaction,” “comprehensive support,” and “reconstruction of a normal family.” Accordingly, FCC eliminated borders between professional and non-professional caregivers and built close relationships among them in the NICU. It also provided for the needs of neonates, their families, and even professional caregivers through perceived and received support. Conclusions: Parents of the neonates admitted to the NICU experience hard moments. They not only play the role of primary caregivers, but they also receive the care. Focusing on the different meanings of this care from the caregivers’ points of view and having managers provide certain requirements can guarantee the establishment of comprehensive care for clients and proper support for the staff in this uni

Effects of 20–100 nm particles on liquid clouds in the clean summertime Arctic

Observations addressing effects of aerosol par- ticles on summertime Arctic clouds are limited. An air- borne study, carried out during July 2014 from Resolute Bay, Nunavut, Canada, as part of the Canadian NETCARE project, provides a comprehensive in situ look into some effects of aerosol particles on liquid clouds in the clean environment of the Arctic summer. Median cloud droplet number concentrations (CDNC) from 62 cloud samples are 10 cm−3 for low-altitude cloud (clouds topped below 200 m) and 101 cm−3 for higher-altitude cloud (clouds based above 200m). The lower activation size of aerosol particles is ≤50nm diameter in about 40% of the cases. Particles as small as 20 nm activated in the higher-altitude clouds consis- tent with higher supersaturations (S) for those clouds inferred from comparison of the CDNC with cloud condensation nu- cleus (CCN) measurements. Over 60 % of the low-altitude cloud samples fall into the CCN-limited regime of Mauritsen et al. (2011), within which increases in CDNC may increase liquid water and warm the surface. These first observations of that CCN-limited regime indicate a positive association of the liquid water content (LWC) and CDNC, but no associ- ation of either the CDNC or LWC with aerosol variations. Above the Mauritsen limit, where aerosol indirect cooling may result, changes in particles with diameters from 20 to 100nm exert a relatively strong influence on the CDNC. Within this exceedingly clean environment, as defined by low carbon monoxide and low concentrations of larger parti- cles, the background CDNC are estimated to range between 16 and 160 cm−3, where higher values are due to activation of particles ≤ 50 nm that likely derive from natural sources. These observations offer the first wide-ranging reference for the aerosol cloud albedo effect in the summertime Arctic