WorldWideScience

Sample records for family zinc sensor

  1. Zinc-dependent carbapenemases in clinical isolates of family Enterobacteriaceae

    OpenAIRE

    Rai, S; V Manchanda; Singh, N P; I R Kaur

    2011-01-01

    Purpose: The emergence and spread of zinc-dependent carbapenem resistance has become a diagnostic challenge for clinical microbiologists. The objective of the present study was to screen zinc-dependent carbapenemase activity in clinical isolates of family Enterobacteriaceae. Materials and Methods: A total of 102 multidrug-resistant organisms (MDROs), non-repeat clinical isolates of family Enterobacteriaceae from two tertiary care centres in Delhi, were screened for carbapenemase production by...

  2. Fluorescence sensor for sequential detection of zinc and phosphate ions

    Science.gov (United States)

    An, Miran; Kim, Bo-Yeon; Seo, Hansol; Helal, Aasif; Kim, Hong-Seok

    2016-12-01

    A new, highly selective turn-on fluorescent chemosensor based on 2-(2‧-tosylamidophenyl)thiazole (1) for the detection of zinc and phosphate ions in ethanol was synthesized and characterized. Sensor 1 showed a high selectivity for zinc compared to other cations and sequentially detected hydrogen pyrophosphate and hydrogen phosphate. The fluorescence mechanism can be explained by two different mechanisms: (i) the inhibition of excited-state intramolecular proton transfer (ESIPT) and (ii) chelation-induced enhanced fluorescence by binding with Zn2 +. The sequential detection of phosphate anions was achieved by the quenching and subsequent revival of ESIPT.

  3. Polyacrylate microspheres for tunable fluorimetric zinc ions sensor.

    Science.gov (United States)

    Woźnica, Emilia; Maksymiuk, Krzysztof; Michalska, Agata

    2014-01-07

    A novel concept of optical fluorimetric sensing using polymeric microspheres is explored on example of zinc ions sensors. The novel approach proposed uses the advantage of concomitant presence in a microsphere of two compounds: a receptor, fluorescently silent complexing ligand and an optical transducer, fluorescent compound. Binding of the analyte by the ligand affects its absorption spectrum, leading to decrease of the free ligand absorption and increase of complex absorption band. The decrease of free ligand absorption exposes emission of the transducer, yielding increase in fluorescence intensity on analyte concentration increase. This approach was verified experimentally using Zn(2+) as a model analyte, the fluorimetric sensor obtained uses 1-(2-pyridylazo)-2-naphthol (PAN) as analyte sensitive receptor and pyrene as optical transducer. In the absence of zinc ions in the sample emission of pyrene embedded in the spheres was significantly quenched, whereas increase of Zn(2+) ions concentration in the sample resulted in dependence of fluorescence intensity on logarithm of zinc ions concentration in extraordinary wide range, from 10(-7) to 0.1 M. The response mechanism was explained by surface accumulation of zinc ion-PAN complex on the microsphere/sample solution interface. It was also shown that introduction of cation-exchanging sites to the microspheres significantly alters the responses pattern leading to high sensitivity over relatively limited concentration range (3-4 orders of magnitude). In the latter case the observed responses can be tuned to occur in chosen concentration range, simply by adjusting sample pH.

  4. Improved zinc oxide film for gas sensor applications

    Indian Academy of Sciences (India)

    S Roy; S Basu

    2002-11-01

    Zinc oxide (ZnO) is a versatile material for different commercial applications such as transparent electrodes, piezoelectric devices, varistors, SAW devices etc because of its high piezoelectric coupling, greater stability of its hexagonal phase and its pyroelectric property. In fact, ZnO is a potential material for gas sensor applications. Good quality ZnO films were deposited on glass and quartz substrates by a novel CVD technique using zinc acetate as the starting solution. X-ray diffraction confirmed the crystallinity of the zinc oxide film and SEM study revealed uniform deposition of fine grains. Undoped ZnO films were used for detection of dimethylamine (DMA) and H2 at different temperatures by recording the change in resistivity of the film in presence of the test gases. The response was faster and the sensitivity was higher compared to the earlier reported ZnO based sensors developed in our laboratory. The main objective of this work was to study the selectivity of the ZnO film for a particular gas in presence of the others. The operating temperature was found to play a key role in the selectivity of such sensors.

  5. Zinc selective ionophores for potentiometric and optical sensors

    Energy Technology Data Exchange (ETDEWEB)

    Lindner, E.; Horvath, M.; Toth, K.; Pungor, E.; Bitter, I.; Agai, B.; Toeke, L. (Technical Univ. of Budapest (Hungary))

    1992-03-01

    Iminodiacetamide derivatives were synthesized and studied as ionophores in plasticized poly(vinyl chloride) membranes with potentiometric and optical transduction. The N-benzyl and N-phenyl derivatives proved to have a distinct zinc selectivity preferring Zn{sup 2+} over Ca{sup 2+}, Na{sup +} by factors of 6x10{sup 5} and 3x10{sup 4}, respectively. All ionophores exhibit a serious proton interference (log K{sup pot}{sub Zn{sup ++}}, {sub H{sup +}} {approximately} 6) which suggests that all application of this type of ionophores based sensors are limited to hydrogen ion buffer solution at pH {>=} 6.

  6. A Surface Acoustic Wave Ethanol Sensor with Zinc Oxide Nanorods

    Directory of Open Access Journals (Sweden)

    Timothy J. Giffney

    2012-01-01

    Full Text Available Surface acoustic wave (SAW sensors are a class of piezoelectric MEMS sensors which can achieve high sensitivity and excellent robustness. A surface acoustic wave ethanol sensor using ZnO nanorods has been developed and tested. Vertically oriented ZnO nanorods were produced on a ZnO/128∘ rotated Y-cut LiNbO3 layered SAW device using a solution growth method with zinc nitrate, hexamethylenetriamine, and polyethyleneimine. The nanorods have average diameter of 45 nm and height of 1 μm. The SAW device has a wavelength of 60 um and a center frequency of 66 MHz at room temperature. In testing at an operating temperature of 270∘C with an ethanol concentration of 2300 ppm, the sensor exhibited a 24 KHz frequency shift. This represents a significant improvement in comparison to an otherwise identical sensor using a ZnO thin film without nanorods, which had a frequency shift of 9 KHz.

  7. Zinc oxide nanowires on carbon microfiber as flexible gas sensor

    Science.gov (United States)

    Tonezzer, M.; Lacerda, R. G.

    2012-03-01

    In the past years, zinc oxide nanowires (ZnO NWs) have been proven to be an excellent material for gas sensors. In this work, we used ZnO nanowires in a novel architecture integrated on a carbon microfiber (μC) textile. This innovative design permits us to obtain mechanical flexibility, while the absence of any lithographic technique allows a large-area and low-cost fabrication of gas sensors. The performances of the devices are investigated for both oxidizing and reducing gases. The nano-on-micro structure of the sensor provides a high surface-to-volume ratio, leading to a fast and intense response for both oxygen (O2) and hydrogen (H2) gases. The sensor response has an optimum temperature condition at 280 °C with a response value of 10 for oxygen and 11 for hydrogen. The limit of detection (LoD) has been found to be 2 and 4 ppm for oxygen and hydrogen, respectively. Additionally, the sensor response and recovery time is small being less than 10 s for both O2 and H2.

  8. Potentiometric Zinc Ion Sensor Based on Honeycomb-Like NiO Nanostructures

    Directory of Open Access Journals (Sweden)

    Magnus Willander

    2012-11-01

    Full Text Available In this study honeycomb-like NiO nanostructures were grown on nickel foam by a simple hydrothermal growth method. The NiO nanostructures were characterized by field emission electron microscopy (FESEM, high resolution transmission electron microscopy (HRTEM and X-ray diffraction (XRD techniques. The characterized NiO nanostructures were uniform, dense and polycrystalline in the crystal phase. In addition to this, the NiO nanostructures were used in the development of a zinc ion sensor electrode by functionalization with the highly selective zinc ion ionophore 12-crown-4. The developed zinc ion sensor electrode has shown a good linear potentiometric response for a wide range of zinc ion concentrations, ranging from 0.001 mM to 100 mM, with sensitivity of 36 mV/decade. The detection limit of the present zinc ion sensor was found to be 0.0005 mM and it also displays a fast response time of less than 10 s. The proposed zinc ion sensor electrode has also shown good reproducibility, repeatability, storage stability and selectivity. The zinc ion sensor based on the functionalized NiO nanostructures was also used as indicator electrode in potentiometric titrations and it has demonstrated an acceptable stoichiometric relationship for the determination of zinc ion in unknown samples. The NiO nanostructures-based zinc ion sensor has potential for analysing zinc ion in various industrial, clinical and other real samples.

  9. Ammonia sensor and antibacterial activities of green zinc oxide nanoparticles

    Directory of Open Access Journals (Sweden)

    S. Khaleel Basha

    2016-09-01

    Full Text Available Zinc oxide nanoparticles was synthesized by alginate (A through a rapid and a facile step in the aqueous solution condition at room temperature. Fabrication of zinc oxide nanoparticles was characterized by ATR-FTIR, TEM and XRD. ATR-FTIR analysis confirmed that the A/ZnO NPs were encapsulated by the polymerized alginate. Their shape, structure and composition were assessed by SEM. TEM and XRD analysis indicated that the A/ZnO NPs give evidence of the crystalline nature of ZnO and hybrid NPs structure, which is suitable for ammonia gas sensor development. The controlled size of the A/ZnO NPs obtained using this innovative synthesis strategy minimizes the response time of 2–3 s to sense the ammonia gas significantly with a detection limit of 1 ppm were found at room temperature. The antibacterial tests revealed that the A/ZnO NPs exhibits a potent activity against gram positive and gram negative bacteria.

  10. CSA doped polypyrrole-zinc oxide thin film sensor

    Science.gov (United States)

    Chougule, M. A.; Jundale, D. M.; Raut, B. T.; Sen, Shashwati; Patil, V. B.

    2013-02-01

    The polypyrrole-zinc oxide (PPy-ZnO) hybrid sensor doped with different weight ratios of camphor sulphonic acid (CSA) were prepared by spin coating technique. These CSA doped PPy-ZnO hybrids were characterized by field emission scanning electron microscope (FESEM) and fourier transform infrared (FTIR) which proved the formation of polypyrrole, PPy-ZnO and the interaction between polypyrrole - ZnO (PPy-ZnO) hybrid with CSA doping. The gas sensing properties of the PPy-ZnO hybrid films doped with CSA have been studied for oxidizing (NO2) as well as reducing (H2S, NH3, CH4OH and CH3OH) gases at room temperature. We demonstrate that CSA doped PPy-ZnO hybrid films are highly selective to NO2 along with high-sensitivity at low concentration (80% to 100 ppm) and better stability, which suggested that the CSA doped PPy-ZnO hybrid films are potential candidate for NO2 detection at room temperature.

  11. Zinc-dependent carbapenemases in clinical isolates of family Enterobacteriaceae

    Directory of Open Access Journals (Sweden)

    S Rai

    2011-01-01

    Full Text Available Purpose: The emergence and spread of zinc-dependent carbapenem resistance has become a diagnostic challenge for clinical microbiologists. The objective of the present study was to screen zinc-dependent carbapenemase activity in clinical isolates of family Enterobacteriaceae. Materials and Methods: A total of 102 multidrug-resistant organisms (MDROs, non-repeat clinical isolates of family Enterobacteriaceae from two tertiary care centres in Delhi, were screened for carbapenemase production by a modified Hodge test (MHT and additionally by a re-modified Hodge test, EDTA double disc synergy test, and combined disc test (or disc enhancement test to determine zinc dependence of carbapenemases harbouring bacteria. Results: Of the total 102 clinical isolates (June through November 2010, 91 were from urine and 11 were from blood specimens. The isolates were obtained from patients visiting the outpatient department (18 isolates, admitted in non-ICU inpatient care units (74 isolates and patients admitted in ICUs (4 isolates. MHT identified 92 (90.2% isolates as carbapenemases producers. Among those found negative for MHT (n=10, metallo-beta-lactamases (MBLs activity was demonstrated through the EDTA disc diffusion synergy test and the combined disc test in 8 and 9 isolates respectively. A total of 63 (61.7% isolates demonstrated MBL activity despite in vitro sensitivity to Imipenem. Conclusions: The study demonstrated that supplementing the MHT with at least one of the screening methods increases the likelihood of picking up such isolates that may be missed by the MHT. The study also demonstrates the wide-spread presence of MBLs in Enterobacteriaceae members from patients visiting hospitals in east Delhi.

  12. Chlorine sensing properties of zinc oxide resistive gas sensor doped with platinum

    Science.gov (United States)

    Fiedot, M.; Suchorska-Woźniak, P.; Rac, O.; Nawrot, W.; Teterycz, H.

    2016-11-01

    In presented studies resistive chlorine gas sensor with gas sensitive layer in the form of zinc oxide microrods doped with platinum was developed. The growth of active layer was carried out in water solution containing zinc nitrate (V), hexamethylenetetramine and chloroplatinic acid using the chemical bath deposition method. The structure and morphology of obtained sensors was characterized by scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX). To determine the chlorine gas sensing properties Temperature-Stimulated Conductance method (TSC) was used. During the measurements sensor was tested in a reference atmosphere and an atmosphere with 2, 5 or 8 ppm of chlorine. Obtained results have shown that zinc oxide microrods doped with platinum were obtained. TSC measurements showed that developed sensor allows to detect chlorine with very good sensitivity.

  13. Thin film zinc oxide gas sensor fabricated using near-field electrospray

    Science.gov (United States)

    Zheng, Gaofeng; Zhu, Ping; Sun, Lingling; Jiang, Jiaxin; Liu, Juan; Wang, Xiang; Li, Wenwang

    2016-12-01

    Near-field electrospray was used to deposit zinc acetate precursor particles over comb electrodes. These particles were heated and oxidized to form a zinc oxide (ZnO) semiconductor at 500 °C. The resulting ZnO thin film on the comb electrode was incorporated into a gas sensor, which was examined using a custom built measurement system. The current that was measured through the electrodes was used to calculate the resistance of the ZnO between the fingers of the comb electrode. The resistance decreased as the sensor was exposed to the target gas of ethanol, while the sensing response (R0/Rg) increased at higher concentrations of target gas. The ZnO sensor displayed high sensitivity because of the small diameters and high specific surface area of the electrospray particles. The ZnO sensors show great promise for use as micro/nano gas sensors as they exhibit high sensitivity, repeatability and stability.

  14. Zinc finger peptide based optic sensor for detection of zinc ions.

    Science.gov (United States)

    Verma, Neelam; Kaur, Gagandeep

    2016-12-15

    In the present work, polyacrylamide gel has been used as a matrix for the immobilization of zinc finger peptide and fluorescent dye acrydine orange on the micro well plate to fabricate the fluorescence based biosensor for the detection of zinc ions in milk samples. The fluorescent dye moves in the hydrophobic groove formed after folding of the peptide in the presence of zinc ions. Under optimized conditions, linear range was observed between 0.001µg/l to 10µg/l of Zinc ions, with a lowest detection limit of 0.001µg/l and response time of 5min. Presented biosensor has shown 20% decrease in fluorescent intensity values after 5 regenerations and stable for more than one month, stored at 4°C. Interference study with other metal ions like lead, cadmium and copper showed a negligible change in fluorescence intensity in comparison to zinc ions. Developed bio sensing system was found to be novel, quick, reliable, miniaturized, stable, reproducible and repeatable and specific for zinc ion, which has been applied to various milk samples.

  15. Dual Readout BRET/FRET Sensors for Measuring Intracellular Zinc

    Science.gov (United States)

    2016-01-01

    Genetically encoded FRET-based sensor proteins have significantly contributed to our current understanding of the intracellular functions of Zn2+. However, the external excitation required for these fluorescent sensors can give rise to photobleaching and phototoxicity during long-term imaging, limits applications that suffer from autofluorescence and light scattering, and is not compatible with light-sensitive cells. For these applications, sensor proteins based on Bioluminescence Resonance Energy Transfer (BRET) would provide an attractive alternative. In this work, we used the bright and stable luciferase NanoLuc to create the first genetically encoded BRET sensors for measuring intracellular Zn2+. Using a new sensor approach, the NanoLuc domain was fused to the Cerulean donor domain of two previously developed FRET sensors, eCALWY and eZinCh-2. In addition to preserving the excellent Zn2+ affinity and specificity of their predecessors, these newly developed sensors enable both BRET- and FRET-based detection. While the dynamic range of the BRET signal for the eCALWY-based BLCALWY-1 sensor was limited by the presence of two competing BRET pathways, BRET/FRET sensors based on the eZinCh-2 scaffold (BLZinCh-1 and -2) yielded robust 25–30% changes in BRET ratio. In addition, introduction of a chromophore-silencing mutation resulted in a BRET-only sensor (BLZinCh-3) with increased BRET response (50%) and an unexpected 10-fold increase in Zn2+ affinity. The combination of robust ratiometric response, physiologically relevant Zn2+ affinities, and stable and bright luminescence signal offered by the BLZinCh sensors allowed monitoring of intracellular Zn2+ in plate-based assays as well as intracellular BRET-based imaging in single living cells in real time. PMID:27547982

  16. Chemical-Biological Properties of Zinc Sensors TSQ and Zinquin: Formation of Sensor-Zn-Protein Adducts versus Zn(Sensor)2 Complexes.

    Science.gov (United States)

    Nowakowski, Andrew B; Meeusen, Jeffrey W; Menden, Heather; Tomasiewicz, Henry; Petering, David H

    2015-12-21

    Fluorescent zinc sensors are the most commonly used tool to study the intracellular mobile zinc status within cellular systems. Previously, we have shown that the quinoline-based sensors Zinquin and 6-methoxy-8-p-toluenesulfonamido-quinoline (TSQ) predominantly form ternary adducts with members of the Zn-proteome. Here, the chemistries of these sensors are further characterized, including how Zn(sensor)2 complexes may react in an intracellular environment. We demonstrate that these sensors are typically used in higher concentrations than needed to obtain maximum signal. Exposing cells to either Zn(Zinquin)2 or Zn(TSQ)2 resulted in efficient cellular uptake and the formation of sensor-Zn-protein adducts as evidenced by both a fluorescence spectral shift toward that of ternary adducts and the localization of the fluorescence signal within the proteome after gel filtration of cellular lysates. Likewise, reacting Zn(sensor)2 with the Zn-proteome from LLC-PK1 cells resulted in the formation of sensor-Zn-protein ternary adducts that could be inhibited by first saturating the Zn- proteome with excess sensor. Further, a native SDS-PAGE analysis of the Zn-proteome reacted with either the sensor or the Zn(sensor)2 complex revealed that both reactions result in the formation of a similar set of sensor-Zn-protein fluorescent products. The results of this experiment also demonstrated that TSQ and Zinquin react with different members of the Zn-proteome. Reactions with the model apo-Zn-protein bovine serum albumin showed that both Zn(TSQ)2 and Zn(Zinquin)2 reacted to form ternary adducts with its apo-Zn-binding site. Moreover, incubating Zn(sensor)2 complexes with non-zinc binding proteins failed to elicit a spectral shift in the fluorescence spectrum, supporting the premise that blue-shifted emission spectra are due to sensor-Zn-protein ternary adducts. It was concluded that Zn(sensors)2 species do not play a significant role in the overall reaction between these sensors and

  17. Development of Resistance-Based pH Sensor Using Zinc Oxide Nanorods.

    Science.gov (United States)

    Copal, Vernalyn C; Tuico, Anthony R; Mendoza, Jamie P; Ferrolino, John Paul R; Vergara, Christopher Jude T; Salvador, Arnel A; Estacio, Elmer S; Somintac, Armando S

    2016-06-01

    The resistance-based pH sensing capability of ZnO nanorods was presented in this study. Interdigitated finger structures of nickel/gold (Ni/Au) electrodes were fabricated on the substrates prior to the sensing material. The effect of varying electrode widths was also considered. Zinc oxide (ZnO) film, as seed layer, was deposited via spray pyrolysis, and zinc oxide nanorods (ZnO-NRs) were grown via low temperature chemical bath deposition. Resistance measurements have shown plausible difference in varying pH of a test solution. The sensor was found reasonably more appreciable in sensing acidic solutions. The electrode widths were also found to relay substantial consequence in the resistance-based sensor. The least electrode-width design has shown a significant increase in the sensitivity of the sensor, with higher initial resistance and greater range of response.

  18. Thin film zinc oxide gas sensor fabricated using near-field electrospray

    Directory of Open Access Journals (Sweden)

    Gaofeng Zheng

    2016-12-01

    Full Text Available Near-field electrospray was used to deposit zinc acetate precursor particles over comb electrodes. These particles were heated and oxidized to form a zinc oxide (ZnO semiconductor at 500 °C. The resulting ZnO thin film on the comb electrode was incorporated into a gas sensor, which was examined using a custom built measurement system. The current that was measured through the electrodes was used to calculate the resistance of the ZnO between the fingers of the comb electrode. The resistance decreased as the sensor was exposed to the target gas of ethanol, while the sensing response (R0/Rg increased at higher concentrations of target gas. The ZnO sensor displayed high sensitivity because of the small diameters and high specific surface area of the electrospray particles. The ZnO sensors show great promise for use as micro/nano gas sensors as they exhibit high sensitivity, repeatability and stability.

  19. Functionalised zinc oxide nanowire gas sensors: Enhanced NO2 gas sensor response by chemical modification of nanowire surfaces

    Directory of Open Access Journals (Sweden)

    Eric R. Waclawik

    2012-05-01

    Full Text Available Surface coating with an organic self-assembled monolayer (SAM can enhance surface reactions or the absorption of specific gases and hence improve the response of a metal oxide (MOx sensor toward particular target gases in the environment. In this study the effect of an adsorbed organic layer on the dynamic response of zinc oxide nanowire gas sensors was investigated. The effect of ZnO surface functionalisation by two different organic molecules, tris(hydroxymethylaminomethane (THMA and dodecanethiol (DT, was studied. The response towards ammonia, nitrous oxide and nitrogen dioxide was investigated for three sensor configurations, namely pure ZnO nanowires, organic-coated ZnO nanowires and ZnO nanowires covered with a sparse layer of organic-coated ZnO nanoparticles. Exposure of the nanowire sensors to the oxidising gas NO2 produced a significant and reproducible response. ZnO and THMA-coated ZnO nanowire sensors both readily detected NO2 down to a concentration in the very low ppm range. Notably, the THMA-coated nanowires consistently displayed a small, enhanced response to NO2 compared to uncoated ZnO nanowire sensors. At the lower concentration levels tested, ZnO nanowire sensors that were coated with THMA-capped ZnO nanoparticles were found to exhibit the greatest enhanced response. ΔR/R was two times greater than that for the as-prepared ZnO nanowire sensors. It is proposed that the ΔR/R enhancement in this case originates from the changes induced in the depletion-layer width of the ZnO nanoparticles that bridge ZnO nanowires resulting from THMA ligand binding to the surface of the particle coating. The heightened response and selectivity to the NO2 target are positive results arising from the coating of these ZnO nanowire sensors with organic-SAM-functionalised ZnO nanoparticles.

  20. Biomimetic ion nanochannels as a highly selective sequential sensor for zinc ions followed by phosphate anions.

    Science.gov (United States)

    Han, Cuiping; Su, Haiyan; Sun, Zhongyue; Wen, Long; Tian, Demei; Xu, Kai; Hu, Junfeng; Wang, Aming; Li, Haibing; Jiang, Lei

    2013-07-08

    A novel biomimetic ion-responsive multi-nanochannel system is constructed by covalently immobilizing a metal-chelating ligand, 2,2'-dipicolylamine (DPA), in polyporous nanochannels prepared in a polymeric membrane. The DPA-modified multi-nanochannels show specific recognition of zinc ions over other common metal ions, and the zinc-ion-chelated nanochannels can be used as secondary sensors for HPO4(2-) anions. The immobilized DPA molecules act as specific-receptor binding sites for zinc ions, which leads to the highly selective zinc-ion response through monitoring of ionic current signatures. The chelated zinc ions can be used as secondary recognition elements for the capture of HPO4(2-) anions, thereby fabricating a sensing nanodevice for HPO4(2-) anions. The success of the DPA immobilization and ion-responsive events is confirmed by measurement of the X-ray photoelectron spectroscopy (XPS), contact angle (CA), and current-voltage (I-V) characteristics of the systems. The proposed nanochannel sensing devices display remarkable specificity, high sensitivity, and wide dynamic range. In addition, control experiments performed in complex matrices suggest that this sensing system has great potential applications in chemical sensing, biotechnology, and many other fields.

  1. Phylogenetic Analysis of the Plant-specific Zinc Finger-Homeobox and Mini Zinc Finger Gene Families

    Institute of Scientific and Technical Information of China (English)

    Wei Hu; Claude W.dePamphilis; Hong Ma

    2008-01-01

    Zinc finger-homaodomain proteins (ZHD) are present in many plants;however,the evolutionary history of the ZHD gene family remains largely unknown.We show here that ZHD genes are plant-specific,nearly all intronless,and related to MINI ZINC FINGER (MIF) genes that possess only the zinc finger.Phylogenetic analyses of ZHD genes from representative land plants suggest that non-seed plant ZHD genes occupy basal positions and angiosperm homologs form seven distinct clades.Several clades contain genes from two or more major angiosperm groups,including eudicots,monocots,magnoliids,and other basal angiosperms,indicating that several duplications occurred before the diversification of flowering plants.In addition,specific lineages have experienced more recent duplications.Unlike the ZHD genes,&fiFs are found only from seed plants,possibly derived from ZHDs by loss of the homeodomain before the divergence of seed plants.Moreover,the MIF genes have also undergone relatively recent gene duplications.Finally,genome duplication might have contributed substantially to the expansion of family size in angiosperms and caused a high level of functional redundancy/overlap in these genes.

  2. Zinc up-regulated the expression of the rice metallonthionein gene family and enhanced the zinc tolerance of yeast cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Northern blot and functional complementation assay were employed to analyze the effects of zinc on expression of ten rice metallothionein genes (OsMT-Is) in rice seedlings and the growth of yeast cells transformed with OsMT-Is. Northern blot revealed that in shoots of the rice seedlings treated with different Zn2+ concentrations, expression of most members of OsMT-I family was increased, except the type 4 OsMT-Is (OsMT-I-4a, 4b and 4c). In roots, Zn2+ significantly increased the transcription of OsMT-I-1b and OsMT-I-2c, but reduced the trascription of OsMT-I-1a and OsMT-I-3a. When these ten cDNAs were heterologously expressed in zinc sensitive yeast mutant, all transgenic yeasts showed increased tolerance to Zn2+, and zinc accumulation in these yeast cells also increased.These indicated that OsMT-I family members might respond to extra Zn2+, and they could enhance Zn2+ tolerance of cells by direct binding Zn2+.

  3. Sol-gel zinc oxide humidity sensors integrated with a ring oscillator circuit on-a-chip.

    Science.gov (United States)

    Yang, Ming-Zhi; Dai, Ching-Liang; Wu, Chyan-Chyi

    2014-10-28

    The study develops an integrated humidity microsensor fabricated using the commercial 0.18 μm complementary metal oxide semiconductor (CMOS) process. The integrated humidity sensor consists of a humidity sensor and a ring oscillator circuit on-a-chip. The humidity sensor is composed of a sensitive film and branch interdigitated electrodes. The sensitive film is zinc oxide prepared by sol-gel method. After completion of the CMOS process, the sensor requires a post-process to remove the sacrificial oxide layer and to coat the zinc oxide film on the interdigitated electrodes. The capacitance of the sensor changes when the sensitive film adsorbs water vapor. The circuit is used to convert the capacitance of the humidity sensor into the oscillation frequency output. Experimental results show that the output frequency of the sensor changes from 84.3 to 73.4 MHz at 30 °C as the humidity increases 40 to 90%RH.

  4. Sol-Gel Zinc Oxide Humidity Sensors Integrated with a Ring Oscillator Circuit On-a-Chip

    Directory of Open Access Journals (Sweden)

    Ming-Zhi Yang

    2014-10-01

    Full Text Available The study develops an integrated humidity microsensor fabricated using the commercial 0.18 μm complementary metal oxide semiconductor (CMOS process. The integrated humidity sensor consists of a humidity sensor and a ring oscillator circuit on-a-chip. The humidity sensor is composed of a sensitive film and branch interdigitated electrodes. The sensitive film is zinc oxide prepared by sol-gel method. After completion of the CMOS process, the sensor requires a post-process to remove the sacrificial oxide layer and to coat the zinc oxide film on the interdigitated electrodes. The capacitance of the sensor changes when the sensitive film adsorbs water vapor. The circuit is used to convert the capacitance of the humidity sensor into the oscillation frequency output. Experimental results show that the output frequency of the sensor changes from 84.3 to 73.4 MHz at 30 °C as the humidity increases 40 to 90%RH.

  5. Zinc Oxide-Multi Walled Carbon Nanotubes Nanocomposites for Carbon Monoxide Gas Sensor Application.

    Science.gov (United States)

    Alharbi, Najlaa D; Ansari, M Shahnawaze; Salah, Numan; Khayyat, Suzan A; Khan, Zishan H

    2016-01-01

    Zinc oxide (ZnO)/multi walled carbon nanotubes (MWCNTs) composites based sensors with different ZnO concentrations were fabricated to improve carbon monoxide (CO) gas sensing properties in comparison to the sensors based on bare MWCNTs. To study the structure, morphology and elemental composition of the resultant products, X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM) and Energy dispersive X-ray spectroscopy (EDS) were carried out. It has been observed that as the concentration of ZnO is increased more and more ZnO nanoparticles in the form of nodes get attached to MWCNTs resulting the reduction in average diameter of MWCNTs. The typical response of ZnO/MWCNTs composites based gas sensors for different CO concentrations (40, 100, 140 and 200 ppm) was studied by using very advanced sensing setup attached to I-V measurement system. Different sensing parameters such as: resistive response, sensitivity and response time were estimated at room temperature for all the fabricated sensors. The results indicated that the sensor based on nanocomposite which has 30 mg ZnO dispersed on 20 mg MWCNTs showing highest sensitivity and fastest response. All the sensors showed response times ranging from 8 to 23 seconds. The sensing mechanism behind the sensors based on ZnO/MWCNTs nanocomposites for CO gas at room temperature is also discussed in the present report.

  6. Lab-on-a-Chip Sensor with Evaporated Bismuth Film Electrode for Anodic Stripping Voltammetry of Zinc

    Science.gov (United States)

    Kang, Wenjing; Pei, Xing; Yue, Wei; Bange, Adam; Heineman, William R.; Papautsky, Ian

    2013-01-01

    In this work, we report on the development of a lab-on-a-chip electrochemical sensor that uses an evaporated bismuth electrode to detect zinc using square wave anodic stripping voltammetry. The microscale electrochemical cell consists of a bismuth working electrode, an integrated silver/silver chloride reference electrode, and a gold auxiliary electrode. The sensor demonstrated linear response in 0.1 M acetate buffer at pH 6 with zinc concentrations ranging from 1 μM to 30 μM and a calculated detection limit of 60 nM. The sensor was also able to successfully detect zinc in a bovine serum extract and the results were verified with independent AAS measurements. These results demonstrate the advantageous qualities of this lab-on-a-chip electrochemical sensor for clinical applications, which include a small sample volume (μL scale), reduced cost, short response time and high accuracy at low concentrations of analyte. PMID:24436575

  7. Zinc

    Science.gov (United States)

    ... slow wound healing, poor sense of taste and smell, diarrhea, and nausea. Moderate zinc deficiency is associated ... nose, as it might cause permanent loss of smell. In June 2009, the US Food and Drug ...

  8. Design and characterization of a novel sensor combined imaging and zinc ion sensing

    Science.gov (United States)

    Wang, Jian; Wang, Lili

    2012-05-01

    A novel fluorescent sensor for Zn(II) detection and imaging is developed by incorporating 1-(2-pyridylazo)-2-naphthol (PAN) and Rhodamine B (RB) in a sol-gel film on an end face of a gradient index (GRIN) lens rod which is tightly connected with an imaging fiber. This technique has high-quality imaging capabilities for observing remote sample while measuring Zn(II). The RB and PAN employed in combination as the indicator for zinc-sensing is much cheaper than that of the other zinc-sensitive fluorescent dyes. The sol is prepared by base catalyzed hydrolysis of tetraethylorthosilicate (TEOS) with the addition of 3-glycidyloxypropyltrimethoxysilane (GLYMO) and 3-aminopropyltriethoxysilane (APTES), which is more suitable for Zn(II) detection. The sensor has the linear range of Zn(II) from 0.1 to 1 mmol/L. Simultaneously, it has the capabilities of real-time imaging with the whole system's resolution of 18.73 line pairs/mm. This bi-functional sensor has potential applications in in situ biosensing and other remote measurements.

  9. An Optical Fiber-Based Sensor Array for the Monitoring of Zinc and Copper Ions in Aqueous Environments

    Directory of Open Access Journals (Sweden)

    Steven Kopitzke

    2014-02-01

    Full Text Available Copper and zinc are elements commonly used in industrial applications as aqueous solutions. Before the solutions can be discharged into civil or native waterways, waste treatment processes must be undertaken to ensure compliance with government guidelines restricting the concentration of ions discharged in solution. While currently there are methods of analysis available to monitor these solutions, each method has disadvantages, be it high costs, inaccuracy, and/or being time-consuming. In this work, a new optical fiber-based platform capable of providing fast and accurate results when performing solution analysis for these metals is described. Fluorescent compounds that exhibit a high sensitivity and selectivity for either zinc or copper have been employed for fabricating the sensors. These sensors demonstrated sub-part-per-million detection limits, 30-second response times, and the ability to analyze samples with an average error of under 10%. The inclusion of a fluorescent compound as a reference material to compensate for fluctuations from pulsed excitation sources has further increased the reliability and accuracy of each sensor. Finally, after developing sensors capable of monitoring zinc and copper individually, these sensors are combined to form a single optical fiber sensor array capable of simultaneously monitoring concentration changes in zinc and copper in aqueous environments.

  10. Highly sensitive sensing of zinc(II) by development and characterization of a PVC-based fluorescent chemical sensor

    Science.gov (United States)

    Aksuner, Nur; Henden, Emur; Yenigul, Berrin; Yilmaz, Ibrahim; Cukurovali, Alaaddin

    2011-03-01

    A sensor membrane with excellent performance based on 1-methyl-1-phenyl-3-[1-hydroxyimino-2-(succinimido)ethyl]cyclobutane has been developed for the determination of zinc(II) ions. The sensing membrane is capable of determining zinc(II) with an outstanding high selectivity over a dynamic range between 8.0 × 10 -8 and 1.6 × 10 -4 mol L -1 with a limit of detection of 2.5 × 10 -8 mol L -1 (1.6 μg L -1). It can be easily and completely regenerated by using 0.1 mol L -1 EDTA solution. The optical sensor developed here was found to be stable, cost effective, easy to prepare, and has unique selectivity towards Zn 2+ ion with respect to common metal ions. The proposed sensor was then applied for the determination of zinc in tap water and hair samples with satisfactory results.

  11. The Electrical Characteristics of Aluminium Doped Zinc Oxide Thin Film for Humidity Sensor Applications

    Directory of Open Access Journals (Sweden)

    N. D. Md Sin

    2011-01-01

    Full Text Available The electrical characteristics of aluminum (Al doped zinc oxide (ZnO thin film for high sensitivity humidity sensors are presented. The effects of Al doping concentration at 0∼0.6 at % on the Al doped ZnO thin film properties were investigated using current-voltage measurement. The optical and structural properties were characterized using photoluminescence (PL, scanning emission microscope (SEM, and X-ray diffraction (XRD. Parameter 0.6 at % Aluminum doped show high sensitivity and suitable for humidity sensor. PL show an emissions band with two peaks centered at about 380 nm (ultra-violet (UV and 600 nm (green in a room temperature. The length of the nanorods increases as the doping concentration increases. XRD results show the intensity of the (002 peak decreased with the increasing of doping concentration.

  12. Family of lifetime sensors for medical purposes

    Science.gov (United States)

    Lippitsch, Max E.; Draxler, Sonja

    1995-05-01

    A family of indicators has been developed for fluorescence lifetime-based measurement of oxygen, pH, carbon dioxide, and potassium, all the indicators being derivatives of the same chemical compound and having identical spectral and lifetime properties. The indicators show an absorption accessible to low- cast light sources, a large Stokes shift, and long fluorescence decay time. all indicators can be excited at the same excitation wavelength, monitored at the same emission wavelength, and measured within the same time range. This opens the possibility of building a compact lifetime-based instrument to simultaneously measure blood gases and cations.

  13. A novel member of a zinc transporter family is defective in acrodermatitis enteropathica.

    Science.gov (United States)

    Wang, Kun; Zhou, Bing; Kuo, Yien-Ming; Zemansky, Jason; Gitschier, Jane

    2002-07-01

    The rare inherited condition acrodermatitis enteropathica (AE) results from a defect in the absorption of dietary zinc. Recently, we used homozygosity mapping in consanguineous Middle Eastern kindreds to localize the AE gene to an approximately 3.5-cM region on 8q24. In this article, we identify a gene, SLC39A4, located in the candidate region and, in patients with AE, document mutations that likely lead to the disease. The gene encodes a histidine-rich protein, which we refer to as "hZIP4," which is a member of a large family of transmembrane proteins, some of which are known to serve as zinc-uptake proteins. We show that Slc39A4 is abundantly expressed in mouse enterocytes and that the protein resides in the apical membrane of these cells. These findings suggest that the hZIP4 transporter is responsible for intestinal absorption of zinc.

  14. Volatile organic compound gas sensor based on aluminum-doped zinc oxide with nanoparticle.

    Science.gov (United States)

    Choi, Nak-Jin; Lee, Hyung-Kun; Moon, Seung Eon; Yang, Woo Seok; Kim, Jongdae

    2013-08-01

    Thick film semiconductor gas sensors based on aluminum-doped zinc oxide (AZO) with nanoparticle size were fabricated to detect volatile organic compound (VOC) existed in building, especially, formaldehyde (HCHO) gas which was known as the cause of sick building syndrome. The sensing materials for screen printing were prepared using roll milling process with binder. The crystallite sizes of prepared materials were about 15 nm through X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). Gas response characteristics were examined for formaldehyde (HCHO), benzene, carbon monoxide, carbon dioxide gas existing in building. In particular, the sensors showed responses to HCHO gas at sub ppm as a function of operating temperatures and gas concentrations. Also, we investigated sensitivity, repeativity, selectivity, and response time of sensor. The transients were very sharp, taking less than 2 s for 90% response. The sensor has shown very stable response at 350 degrees C and followed a very good behavior and showed 60% response in 50 ppb HCHO concentration at 350 degrees C operating temperatures.

  15. [Zinc].

    Science.gov (United States)

    Couinaud, C

    1984-10-01

    Zinc is indispensable for life from bacteria to man. As a trace element it is included in numerous enzymes or serves as their activator (more than 80 zinc metallo-enzymes). It is necessary for nucleic acid and protein synthesis, the formation of sulphated molecules (insulin, growth hormone, keratin, immunoglobulins), and the functioning of carbonic anhydrase, aldolases, many dehydrogenases (including alcohol-dehydrogenase, retinal reductase indispensable for retinal rod function), alkaline phosphatase, T cells and superoxide dismutase. Its lack provokes distinctive signs: anorexia, diarrhea, taste, smell and vision disorders, skin lesions, delayed healing, growth retardation, delayed appearance of sexual characteristics, diminished resistance to infection, and it may be the cause of congenital malformations. Assay is now simplified by atomic absorption spectrophotometry in blood or hair. There is a latent lack prior to any disease because of the vices of modern eating habits, and this increases during stress, infections or tissue healing processes. Its lack is accentuated during long-term parenteral feeding or chronic gastrointestinal affections. Correction is as simple as it is innocuous, and zinc supplements should be given more routinely during surgical procedures.

  16. High sensitive formaldehyde graphene gas sensor modified by atomic layer deposition zinc oxide films

    Energy Technology Data Exchange (ETDEWEB)

    Mu, Haichuan; Zhang, Zhiqiang; Wang, Keke; Xie, Haifen, E-mail: hfxie@ecust.edu.cn [Department of Physics, School of Science, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China); Zhao, Xiaojing; Liu, Feng [Department of Physics, Shanghai Normal University, 100 Guilin Road, Shanghai 200234 (China)

    2014-07-21

    Zinc oxide (ZnO) thin films with various thicknesses were fabricated by Atomic Layer Deposition on Chemical Vapor Deposition grown graphene films and their response to formaldehyde has been investigated. It was found that 0.5 nm ZnO films modified graphene sensors showed high response to formaldehyde with the resistance change up to 52% at the concentration of 9 parts-per-million (ppm) at room temperature. Meanwhile, the detection limit could reach 180 parts-per-billion (ppb) and fast response of 36 s was also obtained. The high sensitivity could be attributed to the combining effect from the highly reactive, top mounted ZnO thin films, and high conductive graphene base network. The dependence of ZnO films surface morphology and its sensitivity on the ZnO films thickness was also investigated.

  17. Zinc oxide-based thin film functional layers for chemiresistive sensors

    Energy Technology Data Exchange (ETDEWEB)

    Miller, James B.; Ashok, Tejasvi; Lee, Sojung; Broitman, Esteban

    2012-08-31

    Sol-gel wet-chemical techniques were used to prepare ZnO, Al-ZnO (Al:Zn = 1:10 mol/mol) and Cu-ZnO (Cu:Zn = 1:10 mol/mol) thin films for characterization as functional layers for chemiresistive oxygen sensors. Cu and Al minor components influence the ZnO films' topography and their thermally induced chemical and structural evolution. As prepared (room temperature) films have the structure of layered basic zinc acetate, a lamellar ZnO precursor. Upon annealing at temperatures through 973 K, the films display similar chemical evolution patterns-temperatures above 773 K are needed to completely desorb solvents and decompose precursors. Cu facilitates c-axis orientation of the film as its structure matures, while Al slows its crystallization. Chemiresistive sensors, fabricated by coating thin film functional layers onto interdigitated electrode (IDE) transducers, were evaluated for their responses to oxygen at operating temperatures through 873 K. A ZnO/IDE sensor displays high sensitivity for O{sub 2} at an intermediate temperature, 673 K, reflecting an optimal balance between surface O{sub 2} coverage and carrier availability. At 1:10 mol/mol Cu:Zn and Al:Zn, the developing ZnO structure cannot accommodate all minor component atoms. Surplus atoms accumulate in independent phases at grain boundaries, contributing to both high base resistances (in N{sub 2}) and low sensitivity to oxygen. - Highlights: Black-Right-Pointing-Pointer Cu modification of a ZnO thin film improves c-axis alignment. Black-Right-Pointing-Pointer Al modification of ZnO thin film delays crystallization. Black-Right-Pointing-Pointer At 1:10 mol/mol Zn, the ZnO structure cannot accommodate all Cu or Al atoms. Black-Right-Pointing-Pointer Excess modifier causes high film resistance and low sensitivity as O{sub 2} sensors.

  18. Low-Temperature Photochemically Activated Amorphous Indium-Gallium-Zinc Oxide for Highly Stable Room-Temperature Gas Sensors.

    Science.gov (United States)

    Jaisutti, Rawat; Kim, Jaeyoung; Park, Sung Kyu; Kim, Yong-Hoon

    2016-08-10

    We report on highly stable amorphous indium-gallium-zinc oxide (IGZO) gas sensors for ultraviolet (UV)-activated room-temperature detection of volatile organic compounds (VOCs). The IGZO sensors fabricated by a low-temperature photochemical activation process and exhibiting two orders higher photocurrent compared to conventional zinc oxide sensors, allowed high gas sensitivity against various VOCs even at room temperature. From a systematic analysis, it was found that by increasing the UV intensity, the gas sensitivity, response time, and recovery behavior of an IGZO sensor were strongly enhanced. In particular, under an UV intensity of 30 mW cm(-2), the IGZO sensor exhibited gas sensitivity, response time and recovery time of 37%, 37 and 53 s, respectively, against 750 ppm concentration of acetone gas. Moreover, the IGZO gas sensor had an excellent long-term stability showing around 6% variation in gas sensitivity over 70 days. These results strongly support a conclusion that a low-temperature solution-processed amorphous IGZO film can serve as a good candidate for room-temperature VOCs sensors for emerging wearable electronics.

  19. [Acrodermatitis enteropathica. Anatomo-clinical study of 2 familial cases treated with zinc sulfate].

    Science.gov (United States)

    Baudon, J J; Fontaine, J L; Larrègue, M; Feldmann, G; Laplane, R

    1978-01-01

    Two familial cases of acrodermatitis enteropathica began at the time of weaning, with characteristic dermatologic lesions and digestive signs, resulting in lack of weight gain: at 13 months of age growth future was evident in the elder child. The anatomic lesions were those of an exophagitis and, in the duodenal mucosa, a dilation of the capillaries of the chorion in the absence of villous atrophy. The ultrastructural study showed inclusions in Paneth's cells, and changes in keratin cells, with intra-cytoplasmic vacuoles and abnormal melanin pigment in the skin. The administration of zinc sulphate induced a rapid recovery of cutaneous lesions and resumption of growth. The interruption of treatment resulted twice in a quite immediate relapse of cutaneous signs in the first patient, which was rapidly reversible with the reintroduction of zinc sulphate.

  20. Dynamic imaging of cytosolic zinc in Arabidopsis roots combining FRET sensors and RootChip technology.

    Science.gov (United States)

    Lanquar, Viviane; Grossmann, Guido; Vinkenborg, Jan L; Merkx, Maarten; Thomine, Sébastien; Frommer, Wolf B

    2014-04-01

    Zinc plays a central role in all living cells as a cofactor for enzymes and as a structural element enabling the adequate folding of proteins. In eukaryotic cells, metals are highly compartmentalized and chelated. Although essential to characterize the mechanisms of Zn(2+) homeostasis, the measurement of free metal concentrations in living cells has proved challenging and the dynamics are difficult to determine. Our work combines the use of genetically encoded Förster resonance energy transfer (FRET) sensors and a novel microfluidic technology, the RootChip, to monitor the dynamics of cytosolic Zn(2+) concentrations in Arabidopsis root cells. Our experiments provide estimates of cytosolic free Zn(2+) concentrations in Arabidopsis root cells grown under sufficient (0.4 nM) and excess (2 nM) Zn(2+) supply. In addition, monitoring the dynamics of cytosolic [Zn(2+) ] in response to external supply suggests the involvement of high- and low-affinity uptake systems as well as release from internal stores. In this study, we demonstrate that the combination of genetically encoded FRET sensors and microfluidics provides an attractive tool to monitor the dynamics of cellular metal ion concentrations over a wide concentration range in root cells. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  1. Synthesis and characterization of nano crystalline nickel zinc ferrite for chlorine gas sensor at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Pawar, C. S., E-mail: charudutta-p@yahoo.com [Material Science and Thin Film Research Laboratory, Department of Physics,Shankarrao Mohite Mahavidyalaya, Akluj India (India); Gujar, M. P. [Shri. Shivaji Junior College, Bawada, Dist: Pune (India); Mathe, V. L. [Department of Physics, University of Pune, Pune – 411 007 India (India)

    2015-06-24

    Nano crystalline Nickel Zinc ferrite (Ni{sub 0.25}Zn{sub 0.75}Fe{sub 2}O{sub 4}) thin films were synthesized by Sol Gel method for gas response. The phase and microstructure of the obtained Ni{sub 0.25}Zn{sub 0.75}Fe{sub 2}O{sub 4} thin films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM). The nanostructured Ni{sub 0.25}Zn{sub 0.75}Fe{sub 2}O{sub 4} thin film shows single spinel phase. Magnetic study was obtained with the help of VSM. The effects of working temperature on the gas response were studied. The results reveal that the Ni{sub 0.25}Zn{sub 0.75}Fe{sub 2}O{sub 4} thin film gas sensor shows good selectivity to chlorine gas at room temperature. The sensor shows highest sensitivity (∼50%) at room temperature, indicating its application in detecting chlorine gas at room temperature in the future.

  2. A Zinc Oxide Nanoflower-Based Electrochemical Sensor for Trace Detection of Sunset Yellow

    Science.gov (United States)

    Ya, Yu; Jiang, Cuiwen; Li, Tao; Liao, Jie; Fan, Yegeng; Wei, Yuning; Yan, Feiyan; Xie, Liping

    2017-01-01

    Zinc oxide nanoflower (ZnONF) was synthesized by a simple process and was used to construct a highly sensitive electrochemical sensor for the detection of sunset yellow (SY). Due to the large surface area and high accumulation efficiency of ZnONF, the ZnONF-modified carbon paste electrode (ZnONF/CPE) showed a strong enhancement effect on the electrochemical oxidation of SY. The electrochemical behaviors of SY were investigated using voltammetry with the ZnONF-based sensor. The optimized parameters included the amount of ZnONF, the accumulation time, and the pH value. Under optimal conditions, the oxidation peak current was linearly proportional to SY concentration in the range of 0.50–10 μg/L and 10–70 μg/L, while the detection limit was 0.10 μg/L (signal-to-noise ratio = 3). The proposed method was used to determine the amount of SY in soft drinks with recoveries of 97.5%–103%, and the results were in good agreement with the results obtained by high-performance liquid chromatography. PMID:28282900

  3. Novel membrane potentiometric sulfate ion sensor based on zinc-phthalocyanine for the quick determination of trace amounts of sulfate.

    Science.gov (United States)

    Ganjali, Mohammad Reza; Pourjavid, Mohammad Reza; Shamsipur, Mojtaba; Poursaeri, Taherh; Rezapour, Morteza; Javanbakht, Mehran; Sharghi, Hashem

    2003-07-01

    Poly(vinyl chloride) (PVC) based membranes of zinc-phthalocyanine (ZPC) with hexadecyltrimethylammonium bromide (HTAB) as a cation excluder, and dibutyl phthalate (DBP) and benzyl acetate (BA) as plasticizing solvent mediators were prepared and investigated as a SO4(2-) selective electrode. The best performance was observed with a membrane having a composition of ZPC-PVC-HTAB-BA in a ratio of 5%:32%:3%:60%, which works well over a wide concentration range (1.0 x 10(-2) - 1.0 x 10(-6) M) with a Nemstian slope of -29.2 mV per decade of activity, between the pH values of 2.0 to 7.0. This sensor shows a very fast response time of 10 s, and can be used over a period of 2 months with good reproducibility. The proposed sensor displays excellent selectivity for SO4(2-) over a large number of common inorganic anions. The sensor has been successfully applied for the direct and indirect determination of sulfate and zinc in zinc sulfate tablets, respectively. It was also used as an indicator electrode in the potentiometric titration of sulfate ions with barium ions.

  4. Splendid one-dimensional nanostructures of zinc oxide: a new nanomaterial family for nanotechnology.

    Science.gov (United States)

    Wang, Zhong Lin

    2008-10-28

    Zinc oxide is a unique material that exhibits exceptional semiconducting, piezoelectric, and pyroelectric properties. Nanostructures of ZnO are equally as important as carbon nanotubes and silicon nanowires for nanotechnology and have great potential applications in nanoelectronics, optoelectronics, sensors, field emission, light-emitting diodes, photocatalysis, nanogenerators, and nanopiezotronics. Fundamental understanding about the growth of ZnO nanowires is of critical importance for controlling their size, composition, structure, and corresponding physical and chemical properties. The papers by She et al. and Ito et al. in this issue describe the controlled growth and field-emission properties of individual nanostructures, respectively. These studies provide new approaches and insight into the controlled growth and electrical properties of ZnO nanostructures.

  5. Non-Enzymatic Glucose Sensor Composed of Carbon-Coated Nano-Zinc Oxide

    Science.gov (United States)

    Chung, Ren-Jei; Wang, An-Ni; Liao, Qing-Liang; Chuang, Kai-Yu

    2017-01-01

    Nowadays glucose detection is of great importance in the fields of biological, environmental, and clinical analyzes. In this research, we report a zinc oxide (ZnO) nanorod powder surface-coated with carbon material for non-enzymatic glucose sensor applications through a hydrothermal process and chemical vapor deposition method. A series of tests, including crystallinity analysis, microstructure observation, and electrochemical property investigations were carried out. For the cyclic voltammetric (CV) glucose detection, the low detection limit of 1 mM with a linear range from 0.1 mM to 10 mM was attained. The sensitivity was 2.97 μA/cm2mM, which is the most optimized ever reported. With such good analytical performance from a simple process, it is believed that the nanocomposites composed of ZnO nanorod powder surface-coated with carbon material are promising for the development of cost-effective non-enzymatic electrochemical glucose biosensors with high sensitivity.

  6. Transcriptional activation capacity of the novel PLAG family of zinc finger proteins.

    Science.gov (United States)

    Kas, K; Voz, M L; Hensen, K; Meyen, E; Van de Ven, W J

    1998-09-04

    We have isolated and characterized two novel cDNAs encoding C2H2 zinc finger proteins showing high sequence homology to PLAG1, a protein ectopically activated by promoter swapping or promoter substitution in pleomorphic adenomas with chromosomal abnormalities at chromosome 8q12. PLAG1 and the two new PLAG1 family members (PLAGL1 and PLAGL2) constitute a novel subfamily of zinc finger proteins that recognize DNA and/or RNA. To examine the potential of the three human proteins to modulate transcription, we constructed several PLAG/GAL4 DNA binding domain fusion proteins and measured their ability to activate transcription of a reporter gene construct in different mammalian cell lines and in yeast. Although the carboxyl-terminal part of PLAGL1 shows strong overall transcriptional activity in mesenchymal (COS-1) and epithelial cells (293), both PLAG1 and PLAGL2 transactivate in mesenchymal cells only if depleted from a repressing region. This effect is less profound in epithelial cells. These data suggest that the activation in pleomorphic adenomas of PLAG1 most likely results in uncontrolled activation of downstream target genes.

  7. A tautomeric zinc sensor for ratiometric fluorescence imaging: application to nitric oxide-induced release of intracellular zinc.

    Science.gov (United States)

    Chang, Christopher J; Jaworski, Jacek; Nolan, Elizabeth M; Sheng, Morgan; Lippard, Stephen J

    2004-02-01

    Zinc is an essential metal ion for human growth and development, the disruption of cellular Zn(2+) homeostasis being implicated in several major disorders including Alzheimer's disease, diabetes, and cancer. The molecular mechanisms of Zn(2+) physiology and pathology are insufficiently understood, however, owing in part to the lack of tools for measuring changes in intracellular Zn(2+) concentrations with high spatial and temporal fidelity. To address this critical need, we have synthesized, characterized, and applied an intracellular fluorescent probe for the ratiometric imaging of Zn(2+) based on a tautomeric seminaphthofluorescein platform. Zin-naphthopyr 1 (ZNP1) affords single-excitation, dual-emission ratiometric detection of intracellular Zn(2+) through Zn(2+)-controlled switching between fluorescein and naphthofluorescein tautomeric forms. The probe features visible excitation and emission profiles, excellent selectivity responses for Zn(2+) over competing Ca(2+) and Mg(2+) ions at intracellular concentrations, a dissociation constant (K(d)) for Zn(2+) of zinc binding. We demonstrate the value of the ZNP1 platform for biological applications by imaging changes in intracellular [Zn(2+)] in living mammalian cells. Included is the ratiometric detection of endogenous pools of intracellular Zn(2+) after NO-induced release of Zn(2+) from cellular metalloproteins. We anticipate that ZNP1 and related probes should find utility for interrogating the biology of Zn(2+).

  8. Fabrication and Characterization of a SPR Based Fiber Optic Sensor for the Detection of Chlorine Gas Using Silver and Zinc Oxide

    Directory of Open Access Journals (Sweden)

    Sruthi P. Usha

    2015-04-01

    Full Text Available A fiber optic chlorine gas sensor working on surface plasmon resonance (SPR technique fabricated using coatings of silver and zinc oxide films over unclad core of the optical fiber is reported. The sensor probe is characterized using wavelength interrogation and recording SPR spectra for different concentrations of chlorine gas around the probe. A red shift is observed in the resonance wavelength on increasing the concentration of the chlorine gas. The thickness of the zinc oxide film is optimized to achieve the maximum sensitivity of the sensor. In addition to wavelength interrogation, the sensor can also work on intensity modulation. The selectivity of the sensor towards chlorine gas is verified by carrying out measurements for different gases. The sensor has various advantages such as better sensitivity, good selectivity, reusability, fast response, low cost, capability of online monitoring and remote sensing.

  9. Energetics of allosteric negative coupling in the zinc sensor S. aureus CzrA.

    Science.gov (United States)

    Grossoehme, Nicholas E; Giedroc, David P

    2009-12-16

    The linked equilibria of an allosterically regulated protein are defined by the structures, residue-specific dynamics and global energetics of interconversion among all relevant allosteric states. Here, we use isothermal titration calorimetry (ITC) to probe the global thermodynamics of allosteric negative regulation of the binding of the paradigm ArsR-family zinc sensing repressor Staphylococcus aureus CzrA to the czr DNA operator (CzrO) by Zn(2+). Zn(2+) binds to the two identical binding sites on the free CzrA homodimer in two discernible steps. A larger entropic driving force Delta(-TDeltaS) of -4.7 kcal mol(-1) and a more negative DeltaC(p) characterize the binding of the first Zn(2+) relative to the second. These features suggest a modest structural transition in forming the Zn(1) state followed by a quenching of the internal dynamics on filling the second zinc site, which collectively drive homotropic negative cooperativity of Zn(2+) binding (Delta(DeltaG) = 1.8 kcal mol(-1)). Negative homotropic cooperativity also characterizes Zn(2+) binding to the CzrA*CzrO complex (Delta(DeltaG) = 1.3 kcal mol(-1)), although the underlying energetics are vastly different, with homotropic Delta(DeltaH) and Delta(-TDeltaS) values both small and slightly positive. In short, Zn(2+) binding to the complex fails to induce a large structural or dynamical change in the CzrA bound to the operator. The strong heterotropic negative linkage in this system (DeltaG(c)(t) = 6.3 kcal mol(-1)) therefore derives from the vastly different structures of the apo-CzrA and CzrA*CzrO reference states (DeltaH(c)(t) = 9.4 kcal mol(-1)) in a way that is reinforced by a global rigidification of the allosterically inhibited Zn(2) state off the DNA (TDeltaS(c)(t) = -3.1 kcal mol(-1), i.e., DeltaS(c)(t) > 0). The implications of these findings for other metalloregulatory proteins are discussed.

  10. Nanostructured zinc oxide gas sensors by successive ionic layer adsorption and reaction method and rapid photothermal processing

    Energy Technology Data Exchange (ETDEWEB)

    Lupan, Oleg [Department of Physics, University of Central Florida, PO Box 162385 Orlando, FL, 32816-2385 (United States); Department of Microelectronics and Semiconductor Devices, Technical University of Moldova, bd. Stefan cel Mare 168, FCIM, MD-2004, Chisinau (Moldova, Republic of); Shishiyanu, Sergiu [Department of Microelectronics and Semiconductor Devices, Technical University of Moldova, bd. Stefan cel Mare 168, FCIM, MD-2004, Chisinau (Moldova, Republic of); Chow, Lee [Department of Physics, University of Central Florida, PO Box 162385 Orlando, FL, 32816-2385 (United States)], E-mail: chow@ucf.edu; Shishiyanu, Teodor [Department of Microelectronics and Semiconductor Devices, Technical University of Moldova, bd. Stefan cel Mare 168, FCIM, MD-2004, Chisinau (Moldova, Republic of)

    2008-03-31

    Undoped and Sn, Ni-doped nanostructured ZnO thin films were deposited on glass substrates using a successive ionic layer adsorption and reaction (SILAR) method at room temperature. The SILAR deposited zinc oxide films have been rapid photothermal processing (RPP) at various temperatures to study the effect of annealing on the sensing properties. Structural, electrical and sensing properties were investigated by means of X-ray diffraction (XRD), Energy Dispersive X-ray spectroscopy, scanning electron microscopy, electrical resistivity, and sensitivity measurements. Microstructures of the deposited films were studied for different concentrations of dopants and zinc-complex solution and temperatures. The results of influence of growth processes, doping, and RPP on phase structure, surface morphology, particles size and resistivity values are presented and discussed. The average grain size determined from XRD patterns was 240, 220 and 265 A for ZnO, Sn-ZnO and Ni-ZnO films, respectively. Moreover, electrical characterization of the sensors prepared from SILAR deposited nanostructured zinc oxide thin film has been carried out. The variation in resisitivity of the ZnO film sensors was obtained with doping and post-deposition rapid photothermal processing in vacuum and N{sub 2} ambient. Electrical resistivity measurements showed semiconducting nature with room temperature resistivity 1.5 x 10{sup 5}, 6.1 x 10{sup 2}, 70 {omega} cm for as-deposited ZnO, 4 at.% Ni-ZnO and 4 at.% Sn-ZnO, respectively. These values decreased to 1 x 10{sup 4}, 2 x 10{sup 2}, 30 {omega} cm for RPP annealed films. The types of doping and temperatures of RPP were found to have an important role in determining the sensitivity and resolution of the NO{sub 2}, NH{sub 3} ZnO-based sensors. While the nanostructured ZnO sensor showed higher ammonia sensitivity than that of NO{sub 2}, an enhanced NO{sub 2} sensitivity was noticed with the ZnO films doped with 4 at.% Sn and higher NH{sub 3} sensitivity

  11. Expression and prognostic significance of zinc fingers and homeoboxes family members in renal cell carcinoma

    Science.gov (United States)

    Jeong, Dae Cheon; Han, Myoung-Eun; Kim, Ji-Young; Liu, Liangwen; Jung, Jin-Sup; Oh, Sae-Ock

    2017-01-01

    Zinc fingers and homeoboxes (ZHX) is a transcription repressor family that contains three members; ZHX1, ZHX2, and ZHX3. Although ZHX family members have been associated with the progression of cancer, their values as prognostic factors in cancer patients have been poorly examined. Renal cell carcinoma (RCC) is a highly heterogeneous, aggressive cancer that responds variably to treatment. Thus, prognostic molecular markers are required to evaluate disease progression and to improve the survival. In clear cell RCC (ccRCC), ZHX1 and ZHX3 expression were found to be down-regulated but ZHX2 was up-regulated, and the expressions of ZHX1 and ZHX3 were significantly associated with pathological stage. Furthermore, Kaplan-Meier and multivariate regression analysis showed that reduction in the mRNA expression of ZHX1 was associated with poorer survival. Taken together, the present study shows loss of ZHX1 is correlated with ccRCC progression and suggests it is an independent prognostic marker in ccRCC. PMID:28152006

  12. A subset of the diverse COG0523 family of putative metal chaperones is linked to zinc homeostasis in all kingdoms of life

    Directory of Open Access Journals (Sweden)

    Merchant Sabeeha S

    2009-10-01

    Full Text Available Abstract Background COG0523 proteins are, like the nickel chaperones of the UreG family, part of the G3E family of GTPases linking them to metallocenter biosynthesis. Even though the first COG0523-encoding gene, cobW, was identified almost 20 years ago, little is known concerning the function of other members belonging to this ubiquitous family. Results Based on a combination of comparative genomics, literature and phylogenetic analyses and experimental validations, the COG0523 family can be separated into at least fifteen subgroups. The CobW subgroup involved in cobalamin synthesis represents only one small sub-fraction of the family. Another, larger subgroup, is suggested to play a predominant role in the response to zinc limitation based on the presence of the corresponding COG0523-encoding genes downstream from putative Zur binding sites in many bacterial genomes. Zur binding sites in these genomes are also associated with candidate zinc-independent paralogs of zinc-dependent enzymes. Finally, the potential role of COG0523 in zinc homeostasis is not limited to Bacteria. We have predicted a link between COG0523 and regulation by zinc in Archaea and show that two COG0523 genes are induced upon zinc depletion in a eukaryotic reference organism, Chlamydomonas reinhardtii. Conclusion This work lays the foundation for the pursuit by experimental methods of the specific role of COG0523 members in metal trafficking. Based on phylogeny and comparative genomics, both the metal specificity and the protein target(s might vary from one COG0523 subgroup to another. Additionally, Zur-dependent expression of COG0523 and putative paralogs of zinc-dependent proteins may represent a mechanism for hierarchal zinc distribution and zinc sparing in the face of inadequate zinc nutrition.

  13. BODIPY-based self-assembled nanoparticles as fluorescence turn-on sensor for the selective detection of zinc in human hair.

    Science.gov (United States)

    Jia, Ming-Yan; Wang, Yu; Liu, Yang; Niu, Li-Ya; Feng, Liang

    2016-11-15

    Zinc plays important roles in regulating physiological and pathological processes. Regrettably, mild to moderate zinc deficiency is common worldwide. Hair Zn(2+) concentration, which reflects a zinc storage status, is useful for tracking trends in zinc status within populations. In this work, we report BODIPY-based self-assembled nanoparticles (NPs) as fluorescence turn-on sensor for the selective sensing of Zn(2+) in human hair. The BODIPY monomers (BAN) self-assemble in aqueous medium to form nonfluorescent NPs. In the presence of Zn(2+) ions, the NPs selectively show an obvious turn-on fluorescence change. This selective response of the NPs allows the determination and quantification of Zn(2+) in human hair with a detection limit of 61.3nM. This study demonstrates that the small molecule self-assembled nanoparticle is a versatile and useful tool, and shows great potential for applications in sensing of important analytes in biological systems.

  14. Nanostructures of zinc oxide

    Directory of Open Access Journals (Sweden)

    Zhong Lin Wang

    2004-06-01

    Full Text Available Zinc oxide (ZnO is a unique material that exhibits semiconducting, piezoelectric, and pyroelectric multiple properties. Using a solid-vapor phase thermal sublimation technique, nanocombs, nanorings, nanohelixes/nanosprings, nanobows, nanobelts, nanowires, and nanocages of ZnO have been synthesized under specific growth conditions. These unique nanostructures unambiguously demonstrate that ZnO is probably the richest family of nanostructures among all materials, both in structures and properties. The nanostructures could have novel applications in optoelectronics, sensors, transducers, and biomedical science because it is bio-safe.

  15. Direct binding of specific AUF1 isoforms to tandem zinc finger domains of tristetraprolin (TTP) family proteins.

    Science.gov (United States)

    Kedar, Vishram P; Zucconi, Beth E; Wilson, Gerald M; Blackshear, Perry J

    2012-02-17

    Tristetraprolin (TTP) is the prototype of a family of CCCH tandem zinc finger proteins that can bind to AU-rich elements in mRNAs and promote their decay. TTP binds to mRNA through its central tandem zinc finger domain; it then promotes mRNA deadenylation, considered to be the rate-limiting step in eukaryotic mRNA decay. We found that TTP and its related family members could bind to certain isoforms of another AU-rich element-binding protein, HNRNPD/AUF1, as well as a related protein, laAUF1. The interaction domain within AUF1p45 appeared to be a C-terminal "GY" region, and the interaction domain within TTP was the tandem zinc finger domain. Surprisingly, binding of AUF1p45 to TTP occurred even with TTP mutants that lacked RNA binding activity. In cell extracts, binding of AUF1p45 to TTP potentiated TTP binding to ARE-containing RNA probes, as determined by RNA gel shift assays; AUF1p45 did not bind to the RNA probes under these conditions. Using purified, recombinant proteins and a synthetic RNA target in FRET assays, we demonstrated that AUF1p45, but not AUF1p37, increased TTP binding affinity for RNA ∼5-fold. These data suggest that certain isoforms of AUF1 can serve as "co-activators" of TTP family protein binding to RNA. The results raise interesting questions about the ability of AUF1 isoforms to regulate the mRNA binding and decay-promoting activities of TTP and its family members as well as the ability of AUF1 proteins to serve as possible physical links between TTP and other mRNA decay proteins and structures.

  16. Multiwalled carbon nanotubes-zinc oxide nanocomposites as low temperature toluene gas sensor

    Science.gov (United States)

    Septiani, Ni Luh Wulan; Yuliarto, Brian; Nugraha; Dipojono, Hermawan Kresno

    2017-03-01

    The performance of nanocomposite MWCNT-ZnO thin films was investigated as toluene gas sensor. The nanocomposites MWCNT-ZnO thin films were synthesized by reflux method with the variation of MWCNT:ZnO ratio on 1:0, 3:1, 1:1, 1:3, and 0:1. Crystallinity and morphology characterization show that the crystal structure was not influenced by the presence of MWCNT, and the presence of MWCNTs could prevent the agglomeration of ZnO nanostructure. The dynamic response curve of nanocomposites MWCNT-ZnO thin films shows two different patterns at low temperature region and high temperature region. At low temperature region, the sensor response decreases as the increasing operating temperature and increasing the concentration of ZnO. On the other hand, at high temperature region, the sensor response increases as the increasing operating temperature and increasing the concentration of ZnO. Moreover, the variation concentration of MWCNT and ZnO can decrease the operating temperature of the sensors. The sensor with the ratio of MWCNT:ZnO at 1:3 show highest sensor response that reaches 17% at 150 °C of operating temperature, while the pure MWCNTs and pure ZnO show no response at that temperature.

  17. Effect of covalent and non-covalent linking of zinc(II) phthalocyanine functionalised carbon nanomaterials on the sensor response to ammonia

    OpenAIRE

    Polyakov, Maxim S.; Basova, Tamara V.; Göksel, Meltem; Şenocak, Ahmet; Demirbaş, Erhan; Durmus,Mahmut; Kadem, Burak; Hassan, Aseel

    2017-01-01

    In this work, a comparative study of the sensor response of single walled carbon nanotubes (SWCNTs) and reduced graphene oxide (rGO) covalently and non-covalently functionalised with1-[N-(2-ethoxyethyl)-4-pentynamide]-8(11),15(18),22(25)-tris-{2-[2-(2-ethoxyethoxy) ethoxy]-1-[2-((2-ethoxy ethoxy)-ethoxy)methyl]ethyloxy}zinc(II) phthalocyanine (ZnPc) to ammonia is carried out. It was shown that in the case of SWCNT-based materials both covalent and non-covalent functionalisation with zinc(II) ...

  18. The maize INDETERMINATE1 flowering time regulator defines a highly conserved zinc finger protein family in higher plants

    Directory of Open Access Journals (Sweden)

    Colasanti Joseph

    2006-06-01

    Full Text Available Abstract Background The maize INDETERMINATE1 gene, ID1, is a key regulator of the transition to flowering and the founding member of a transcription factor gene family that encodes a protein with a distinct arrangement of zinc finger motifs. The zinc fingers and surrounding sequence make up the signature ID domain (IDD, which appears to be found in all higher plant genomes. The presence of zinc finger domains and previous biochemical studies showing that ID1 binds to DNA suggests that members of this gene family are involved in transcriptional regulation. Results Comparison of IDD genes identified in Arabidopsis and rice genomes, and all IDD genes discovered in maize EST and genomic databases, suggest that ID1 is a unique member of this gene family. High levels of sequence similarity amongst all IDD genes from maize, rice and Arabidopsis suggest that they are derived from a common ancestor. Several unique features of ID1 suggest that it is a divergent member of the maize IDD family. Although no clear ID1 ortholog was identified in the Arabidopsis genome, highly similar genes that encode proteins with identity extending beyond the ID domain were isolated from rice and sorghum. Phylogenetic comparisons show that these putative orthologs, along with maize ID1, form a group separate from other IDD genes. In contrast to ID1 mRNA, which is detected exclusively in immature leaves, several maize IDD genes showed a broad range of expression in various tissues. Further, Western analysis with an antibody that cross-reacts with ID1 protein and potential orthologs from rice and sorghum shows that all three proteins are detected in immature leaves only. Conclusion Comparative genomic analysis shows that the IDD zinc finger family is highly conserved among both monocots and dicots. The leaf-specific ID1 expression pattern distinguishes it from other maize IDD genes examined. A similar leaf-specific localization pattern was observed for the putative ID1 protein

  19. Synthesis and Characterization of Vanadium Doped Zinc Oxide Thick Film for Chemical Sensor Application

    Directory of Open Access Journals (Sweden)

    Rayees Ahmad Zargar

    2015-01-01

    Full Text Available Zinc oxide and vanadium pentoxide nanoparticles derived by chemical coprecipitation route were used to cast Zn0.96V0.04O thick film by screen printing method. The structural, morphological, optical, and electrical properties of the film were characterized by powder XRD, SEM, Raman, UV-VIS, and DC conductivity techniques. XRD pattern, SEM image, and Raman spectrum of the film confirm the single phase formation of Wurtzite structure with preferential orientation along [101] plane, minor variation in lattice parameters, and vanadium ions substitution at zinc sites. Zn0.96V0.04O pellet has been used for sensing ammonia vapor concentrations in 20–50°C temperature range which exhibits maximum responsiveness and sensitivity at 30°C. The minor variations in resistance are observed with ammonia vapor concentration. The adsorption of ammonia vapors through weak hydrogen bonding and its insertion into lattice by nitrogen lone pairs donation at vacant/defect sites in lattice caused by vanadium doping are considered to explain gas sensing mechanism.

  20. A bisphenol A sensor based on novel self-assembly of zinc phthalocyanine tetrasulfonic acid-functionalized graphene nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Keyu [Fujian Key Lab of Medical Instrument & Pharmaceutical Technology, Yishan Campus, Fuzhou University, Fuzhou, Fujian 350002 (China); Institute of Research for Functional Materials, Yishan Campus, Fuzhou University, Fuzhou, Fujian 350002 (China); College of Chemistry, Qishan Campus, Fuzhou University, Fuzhou, Fujian 350116 (China); Huang, Lei; Qi, Yongbo [Institute of Research for Functional Materials, Yishan Campus, Fuzhou University, Fuzhou, Fujian 350002 (China); College of Chemistry, Qishan Campus, Fuzhou University, Fuzhou, Fujian 350116 (China); Huang, Caixia [Fujian Key Lab of Medical Instrument & Pharmaceutical Technology, Yishan Campus, Fuzhou University, Fuzhou, Fujian 350002 (China); Institute of Research for Functional Materials, Yishan Campus, Fuzhou University, Fuzhou, Fujian 350002 (China); College of Chemistry, Qishan Campus, Fuzhou University, Fuzhou, Fujian 350116 (China); Pan, Haibo, E-mail: hbpan@fzu.edu.cn [Fujian Key Lab of Medical Instrument & Pharmaceutical Technology, Yishan Campus, Fuzhou University, Fuzhou, Fujian 350002 (China); Institute of Research for Functional Materials, Yishan Campus, Fuzhou University, Fuzhou, Fujian 350002 (China); College of Chemistry, Qishan Campus, Fuzhou University, Fuzhou, Fujian 350116 (China); Du, Min [Fujian Key Lab of Medical Instrument & Pharmaceutical Technology, Yishan Campus, Fuzhou University, Fuzhou, Fujian 350002 (China)

    2015-04-01

    In this work, a novel zinc phthalocyanine tetrasulfonic acid (ZnTsPc)-functionalized graphene nanocomposites (f-GN) was synthesized by a simple and efficient electrostatic self-assembly method, where the positive charged GN decorated by (3-aminopropyl) triethoxysilane (APTES) was self-assemblied with ZnTsPc, a two dimensional (2-D) molecules. It not only enhanced its stability for the hybrid structure, but also avoided the reaggregation of ZnTsPc or f-GN themselves. Based on layered ZnTsPc/f-GN nanocomposites modified glassy carbon electrode, a rapid and sensitive sensor was developed for the determination of bisphenol A (BPA). Under the optimal conditions, the oxidation peak current increased linearly with the concentration of BPA in the range of 5.0 × 10{sup −8} to 4.0 × 10{sup −6} M with correlation coefficient 0.998 and limits of detection 2.0 × 10{sup −8} M. Due to high absorption nature for BPA and electron deficiency on ZnTsPc/f-GN, it presented the unique electron pathway arising from π–π stackable interaction during redox process for detecting BPA. The sensor exhibited remarkable long-term stability, good anti-interference and excellent electrocatalytic activity towards BPA detection. - Graphical abstract: 2-D ZnTsPc/f-GN architecture with high BPA absorption efficiency and excellent catalysis of central metal in ZnTsPc was highly promising for BPA sensor. - Highlights: • 2-D ZnTsPc/f-GN architecture was synthesized by electrostatic self-assembly method. • ZnTsPc/f-GN nanocomposites avoided the reaggregation of ZnTsPc and f-GN themselves. • An electrochemical BPA sensor was developed based on ZnTsPc/f-GN nanocomposites. • High absorption for BPA and electron deficiency on the surface of ZnTsPc/f-GN • The proposed sensor could be applied for detection of BPA in real samples.

  1. Zinc Oxide Nanostructures for NO2 Gas-Sensor Applications:A Review

    Institute of Scientific and Technical Information of China (English)

    Rajesh Kumar; O. Al-Dossary; Girish Kumar; Ahmad Umar

    2015-01-01

    Abstract Because of the interesting and multifunctional properties, recently, ZnO nanostructures are considered as excellent material for fabrication of highly sensitive and selective gas sensors. Thus, ZnO nanomaterials are widely used to fabricate efficient gas sensors for the detection of various hazardous and toxic gases. The presented review article is focusing on the recent developments of NO2 gas sensors based on ZnO nanomaterials. The review presents the general introduction of some metal oxide nanomaterials for gas sensing application and finally focusing on the structure of ZnO and its gas sensing mechanisms. Basic gas sensing characteristics such as gas response, response time, recovery time, selectivity, detection limit, stability and recyclability, etc are also discussed in this article. Further, the utilization of various ZnO nanomaterials such as nanorods, nanowires, nano-micro flowers, quantum dots, thin films and nanosheets, etc for the fabrication of NO2 gas sensors are also presented. Moreover, various factors such as NO2 concentrations, annealing temperature, ZnO morphologies and particle sizes, relative humidity, operating temperatures which are affecting the NO2 gas sensing properties are discussed in this review. Finally, the review article is concluded and future directions are presented.

  2. Zinc oxide/redox mediator composite films-based sensor for electrochemical detection of important biomolecules.

    Science.gov (United States)

    Tang, Chun-Fang; Kumar, S Ashok; Chen, Shen-Ming

    2008-09-15

    Electrochemical oxidation of serotonin (SN) onto zinc oxide (ZnO)-coated glassy carbon electrode (GCE) results in the generation of redox mediators (RMs) that are strongly adsorbed on electrode surface. The electrochemical properties of zinc oxide-electrogenerated redox mediator (ZnO/RM) (inorganic/organic) hybrid film-coated electrode has been studied using cyclic voltammetry (CV). The scanning electron microscope (SEM), atomic force microscope (AFM), and electrochemical techniques proved the immobilization of ZnO/RM core/shell microparticles on the electrode surface. The GCE modified with ZnO/RM hybrid film showed two reversible redox peaks in acidic solution, and the redox peaks were found to be pH dependent with slopes of -62 and -60 mV/pH, which are very close to the Nernst behavior. The GCE/ZnO/RM-modified electrode exhibited excellent electrocatalytic activity toward the oxidations of ascorbic acid (AA), dopamine (DA), and uric acid (UA) in 0.1M phosphate buffer solution (PBS, pH 7.0). Indeed, ZnO/RM-coated GCE separated the anodic oxidation waves of DA, AA, and UA with well-defined peak separations in their mixture solution. Consequently, the GCE/ZnO/RMs were used for simultaneous detection of DA, AA, and UA in their mixture solution. Using CV, calibration curves for DA, AA, and UA were obtained over the range of 6.0 x 10(-6) to 9.6 x 10(-4)M, 1.5 x 10(-5) to 2.4 x 10(-4)M, and 5.0 x 10(-5) to 8 x 10(-4)M with correlation coefficients of 0.992, 0.991, and 0.989, respectively. Moreover, ZnO/RM-modified GCE had good stability and antifouling properties.

  3. Zinc Oxide Nanorods Grown on Printed Circuit Board for Extended-Gate Field-Effect Transistor pH Sensor

    Science.gov (United States)

    Van Thanh, Pham; Nhu, Le Thi Quynh; Mai, Hong Hanh; Tuyen, Nguyen Viet; Doanh, Sai Cong; Viet, Nguyen Canh; Kien, Do Trung

    2017-02-01

    Zinc oxide (ZnO) nanorods (NRs) were grown directly on printed circuit boards with a 35-μm-thick copper layer using a seedless galvanic-cell hydrothermal process. The hexagonal structure of the synthesized ZnO NRs was observed by scanning electron microscopy. The microstructural characteristics of the as-grown ZnO NRs were investigated by x-ray diffraction analysis, revealing preferred (002) growth direction. Raman and photoluminescence spectra confirmed the high crystalline quality of the ZnO NRs. As-grown ZnO NRs were then grown for 7 h using the galvanic effect for use as the pH membrane of an extended-gate field-effect transistor pH sensor (pH-EGFET). The current-voltage characteristics showed sensitivity of 15.4 mV/pH and 0.26 (μA)1/2/pH in the linear and saturated region, respectively. Due to their cost effectiveness, low-temperature processing, and ease of fabrication, such devices are potential candidates for use as flexible, low-cost, disposable biosensors.

  4. Zinc(II)-selective ratiometric fluorescent sensors based on inhibition of excited-state intramolecular proton transfer.

    Science.gov (United States)

    Henary, Maged M; Wu, Yonggang; Fahrni, Christoph J

    2004-06-21

    To develop a zinc(II)-selective emission ratiometric probe suitable for biological applications, we explored the cation-induced inhibition of excited-state intramolecular proton transfer (ESIPT) with a series of 2-(2'-benzenesulfonamidophenyl)benzimidazole derivatives. In the absence of Zn(II) at neutral pH, the fluorophores undergo ESIPT to yield a highly Stokes' shifted emission from the proton-transfer tautomer. Coordination of Zn(II) inhibits the ESIPT process and yields a significant hypsochromic shift of the fluorescence emission maximum. Whereas the paramagnetic metal cations Cu(II), Fe(II), Ni(II), Co(II), and Mn(II) result in fluorescence quenching, the emission response is not altered by millimolar concentrations of Ca(II) or Mg(II), rendering the sensors selective for Zn(II) among all biologically important metal cations. Due to the modular architecture of the fluorophore, the Zn(II) binding affinity can be readily tuned by implementing simple structural modifications. The synthesized probes are suitable to gauge free Zn(II) concentrations in the micromolar to picomolar range under physiological conditions.

  5. Zinc Oxide Nanorods Grown on Printed Circuit Board for Extended-Gate Field-Effect Transistor pH Sensor

    Science.gov (United States)

    Van Thanh, Pham; Nhu, Le Thi Quynh; Mai, Hong Hanh; Tuyen, Nguyen Viet; Doanh, Sai Cong; Viet, Nguyen Canh; Kien, Do Trung

    2017-06-01

    Zinc oxide (ZnO) nanorods (NRs) were grown directly on printed circuit boards with a 35- μm-thick copper layer using a seedless galvanic-cell hydrothermal process. The hexagonal structure of the synthesized ZnO NRs was observed by scanning electron microscopy. The microstructural characteristics of the as-grown ZnO NRs were investigated by x-ray diffraction analysis, revealing preferred (002) growth direction. Raman and photoluminescence spectra confirmed the high crystalline quality of the ZnO NRs. As-grown ZnO NRs were then grown for 7 h using the galvanic effect for use as the pH membrane of an extended-gate field-effect transistor pH sensor (pH-EGFET). The current-voltage characteristics showed sensitivity of 15.4 mV/pH and 0.26 ( μA)1/2/pH in the linear and saturated region, respectively. Due to their cost effectiveness, low-temperature processing, and ease of fabrication, such devices are potential candidates for use as flexible, low-cost, disposable biosensors.

  6. Family of fluorescence lifetime sensors for environmental purposes

    Science.gov (United States)

    Draxler, Sonja; Lippitsch, Max E.

    1995-09-01

    A family of indicators has been developed for measuring different analytes, all the indicators being derivatives of the same chemical compound and having identical spectral and lifetime properties. The indicators show an absorption accessible to low-cost light sources, a large Stokes shift, and a long fluorescence decay time. All indicators can be excited at the same excitation wavelength, monitored at the same emission wavelength, and measured within the same time range. This opens the possibility for a compact lifetime-based instrument for water monitoring.

  7. Evolutionary expansion and divergence in a large family of primate-specific zinc finger transcription factor genes

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, A T; Huntley, S; Tran-Gyamfi, M; Baggott, D; Gordon, L; Stubbs, L

    2005-09-28

    Although most genes are conserved as one-to-one orthologs in different mammalian orders, certain gene families have evolved to comprise different numbers and types of protein-coding genes through independent series of gene duplications, divergence and gene loss in each evolutionary lineage. One such family encodes KRAB-zinc finger (KRAB-ZNF) genes, which are likely to function as transcriptional repressors. One KRAB-ZNF subfamily, the ZNF91 clade, has expanded specifically in primates to comprise more than 110 loci in the human genome, yielding large gene clusters in human chromosomes 19 and 7 and smaller clusters or isolated copies at other chromosomal locations. Although phylogenetic analysis indicates that many of these genes arose before the split between old world monkeys and new world monkeys, the ZNF91 subfamily has continued to expand and diversify throughout the evolution of apes and humans. The paralogous loci are distinguished by sequence divergence within their zinc finger arrays indicating a selection for proteins with different DNA binding specificities. RT-PCR and in situ hybridization data show that some of these ZNF genes can have tissue-specific expression patterns, however many KRAB-ZNFs that are near-ubiquitous could also be playing very specific roles in halting target pathways in all tissues except for a few, where the target is released by the absence of its repressor. The number of variant KRAB-ZNF proteins is increased not only because of the large number of loci, but also because many loci can produce multiple splice variants, which because of the modular structure of these genes may have separate and perhaps even conflicting regulatory roles. The lineage-specific duplication and rapid divergence of this family of transcription factor genes suggests a role in determining species-specific biological differences and the evolution of novel primate traits.

  8. A survey of well conserved families of C2H2 zinc-finger genes in Daphnia

    Science.gov (United States)

    2010-01-01

    Background A recent comparative genomic analysis tentatively identified roughly 40 orthologous groups of C2H2 Zinc-finger proteins that are well conserved in "bilaterians" (i.e. worms, flies, and humans). Here we extend that analysis to include a second arthropod genome from the crustacean, Daphnia pulex. Results Most of the 40 orthologous groups of C2H2 zinc-finger proteins are represented by just one or two proteins within each of the previously surveyed species. Likewise, Daphnia were found to possess a similar number of orthologs for all of these small orthology groups. In contrast, the number of Sp/KLF homologs tends to be greater and to vary between species. Like the corresponding mammalian Sp/KLF proteins, most of the Drosophila and Daphnia homologs can be placed into one of three sub-groups: Class I-III. Daphnia were found to have three Class I proteins that roughly correspond to their Drosophila counterparts, dSP1, btd, CG5669, and three Class II proteins that roughly correspond to Luna, CG12029, CG9895. However, Daphnia have four additional KLF-Class II proteins that are most similar to the vertebrate KLF1/2/4 proteins, a subset not found in Drosophila. Two of these four proteins are encoded by genes linked in tandem. Daphnia also have three KLF-Class III members, one more than Drosophila. One of these is a likely Bteb2 homolog, while the other two correspond to Cabot and KLF13, a vertebrate homolog of Cabot. Conclusion Consistent with their likely roles as fundamental determinants of bilaterian form and function, most of the 40 groups of C2H2 zinc-finger proteins are conserved in kind and number in Daphnia. However, the KLF family includes several additional genes that are most similar to genes present in vertebrates but missing in Drosophila. PMID:20433734

  9. The rice B-box zinc finger gene family: genomic identification, characterization, expression profiling and diurnal analysis.

    Directory of Open Access Journals (Sweden)

    Jianyan Huang

    Full Text Available BACKGROUND: The B-box (BBX -containing proteins are a class of zinc finger proteins that contain one or two B-box domains and play important roles in plant growth and development. The Arabidopsis BBX gene family has recently been re-identified and renamed. However, there has not been a genome-wide survey of the rice BBX (OsBBX gene family until now. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we identified 30 rice BBX genes through a comprehensive bioinformatics analysis. Each gene was assigned a uniform nomenclature. We described the chromosome localizations, gene structures, protein domains, phylogenetic relationship, whole life-cycle expression profile and diurnal expression patterns of the OsBBX family members. Based on the phylogeny and domain constitution, the OsBBX gene family was classified into five subfamilies. The gene duplication analysis revealed that only chromosomal segmental duplication contributed to the expansion of the OsBBX gene family. The expression profile of the OsBBX genes was analyzed by Affymetrix GeneChip microarrays throughout the entire life-cycle of rice cultivar Zhenshan 97 (ZS97. In addition, microarray analysis was performed to obtain the expression patterns of these genes under light/dark conditions and after three phytohormone treatments. This analysis revealed that the expression patterns of the OsBBX genes could be classified into eight groups. Eight genes were regulated under the light/dark treatments, and eleven genes showed differential expression under at least one phytohormone treatment. Moreover, we verified the diurnal expression of the OsBBX genes using the data obtained from the Diurnal Project and qPCR analysis, and the results indicated that many of these genes had a diurnal expression pattern. CONCLUSIONS/SIGNIFICANCE: The combination of the genome-wide identification and the expression and diurnal analysis of the OsBBX gene family should facilitate additional functional studies of the Os

  10. A Novel Member of a Zinc Transporter Family Is Defective in Acrodermatitis Enteropathica

    OpenAIRE

    Wang, Kun; Zhou, Bing; Kuo, Yien-Ming; Zemansky, Jason; Gitschier, Jane

    2002-01-01

    The rare inherited condition acrodermatitis enteropathica (AE) results from a defect in the absorption of dietary zinc. Recently, we used homozygosity mapping in consanguineous Middle Eastern kindreds to localize the AE gene to an ∼3.5-cM region on 8q24. In this article, we identify a gene, SLC39A4, located in the candidate region and, in patients with AE, document mutations that likely lead to the disease. The gene encodes a histidine-rich protein, which we refer to as “hZIP4,” which is a me...

  11. A Novel Member of a Zinc Transporter Family Is Defective in Acrodermatitis Enteropathica

    OpenAIRE

    Wang, Kun; Zhou, Bing; Kuo, Yien-Ming; Zemansky, Jason; Gitschier, Jane

    2002-01-01

    The rare inherited condition acrodermatitis enteropathica (AE) results from a defect in the absorption of dietary zinc. Recently, we used homozygosity mapping in consanguineous Middle Eastern kindreds to localize the AE gene to an ∼3.5-cM region on 8q24. In this article, we identify a gene, SLC39A4, located in the candidate region and, in patients with AE, document mutations that likely lead to the disease. The gene encodes a histidine-rich protein, which we refer to as “hZIP4,” which is a me...

  12. Expression of a subset of the Arabidopsis Cys(2)/His(2)-type zinc-finger protein gene family under water stress.

    Science.gov (United States)

    Sakamoto, H; Araki, T; Meshi, T; Iwabuchi, M

    2000-05-02

    The genes encoding Cys(2)/His(2)-type zinc-finger proteins constitute a large family in higher plants. To elucidate the functional roles of these types of protein, four different members of the gene family were cloned from Arabidopsis by PCR-aided methods. One was identical to the already reported gene STZ/ZAT10 and three were as yet unidentified genes, then designated AZF1 (Arabidopsis zinc-finger protein 1), AZF2 and AZF3. The AZF- and STZ-encoded proteins contain two canonical Cys(2)/His(2)-type zinc-finger motifs, separated by a long spacer. Three conserved regions, named B-box, L-box, and DNL-box, were also recognized outside the zinc-finger motifs, as in other members of the two-fingered Cys(2)/His(2)-type zinc-finger protein family. These four genes were positioned on the same branch of a phylogenetic tree constructed based on the zinc-finger motif sequences, suggesting their structural and functional relationship. RNA blot analysis showed that all four genes were mainly expressed in roots and at different levels in other organs. Expression of the four genes responded to water stress. High-salt treatment resulted in elevated levels of expression of all of these genes. Low-temperature treatment increased the expression levels of AZF1, AZF3, and STZ, but not AZF2. Only AZF2 expression was strongly induced by ABA treatment, where the time course of the induction was similar to that caused by high salinity. In situ localization showed that AZF2 mRNA accumulated in the elongation zone of the roots under the salt-stress condition. These results suggest that AZF1, AZF2, AZF3, and STZ are all involved in the water-stress response in an ABA-dependent or -independent pathway to regulate downstream genes.

  13. Laser ablation synthesis of zinc oxide clusters: a new family of fullerenes?

    CERN Document Server

    Bulgakov, A V; Bulgakov, Alexander V.; Ozerov, Igor; Proxy, Wladimir Marine; ccsd-00000864, ccsd

    2003-01-01

    Positively charged zinc oxide clusters ZnnOm (up to n = 16, m <= n) of various stoichiometry were synthesized in the gas phase by excimer ArF laser ablation of a ZnO target and investigated using time-of-flight mass spectrometry. Depending on ablation conditions, either metal rich or stoichiometric clusters dominate in the mass spectrum. When the irradiated target surface is fairly fresh, the most abundant clusters are metal rich with Zn(n+1)On and Zn(n+3)On being the major series. The stoichiometric clusters are observed with an etched ablated surface. The magic numbers at n = 9, 11 and 15 in mass spectra of (ZnO)n clusters indicate that the clusters have hollow spheroid structures related to fullerenes. A local abundance minimum at n = 13 provides an additional evidence for the presence in the ablation plume of fullerene-like (ZnO)n clusters.

  14. Analyzing free zinc(II) ion concentrations in cell biology with fluorescent chelating molecules.

    Science.gov (United States)

    Maret, Wolfgang

    2015-02-01

    Essential metal ions are tightly controlled in biological systems. An understanding of metal metabolism and homeostasis is being developed from quantitative information of the sizes, concentrations, and dynamics of cellular and subcellular metal ion pools. In the case of human zinc metabolism, minimally 24 proteins of two zinc transporter families and a dozen metallothioneins participate in cellular uptake, extrusion, and re-distribution among cellular compartments. Significantly, zinc(ii) ions are now considered signaling ions in intra- and intercellular communication. Such functions require transients of free zinc ions. It is experimentally quite challenging to distinguish zinc that is protein-bound from zinc that is not bound to proteins. Measurement of total zinc is relatively straightforward with analytical techniques such as atomic absorption/emission spectroscopy or inductively coupled plasma mass spectrometry. Total zinc concentrations of human cells are 200-300 μM. In contrast, the pool of non-protein bound zinc is mostly examined with fluorescence microscopy/spectroscopy. There are two widely applied fluorescence approaches, one employing low molecular weight chelating agents ("probes") and the other metal-binding proteins ("sensors"). The protein sensors, such as the CALWY, Zap/ZifCY, and carbonic anhydrase-based sensors, can be genetically encoded and have certain advantages in terms of controlling intracellular concentration, localization, and calibration. When employed correctly, both probes and sensors can establish qualitative differences in free zinc ion concentrations. However, when quantitative information is sought, the assumptions underlying the applications of probes and sensors must be carefully examined and even then measured pools of free zinc ions remain methodologically defined. A consensus is building that the steady-state free zinc ion concentrations in the cytosol are in the picomolar range but there is no consensus on their

  15. Physiological changes and expression characteristics of ZIP family genes under zinc deifciency in navel orange (Citrus sinensis)

    Institute of Scientific and Technical Information of China (English)

    XING Fei; FU Xing-zheng; WANG Nan-qi; XI Jian-long; HUANG Yi; ZHOU Wei; LING Li-li; PENG Liang-zhi

    2016-01-01

    Zinc (Zn) deifciency is widespread among citrus plants, but information about the mechanisms for Zn deifciency response in these plants is scarce. In the present study, different navel orange (Citrus sinensis (L.) Osbeck) leaves with various yelowing levels were sampled in our experimental orchard, and upon estimation of nutrient contents, Zn deifciencies were diagnosed as mild, moderate, and severe. Further analysis of chlorophyl content, photosynthetic characteristics, antioxidant enzyme activities, and expression levels ofZn/Iron-regulated transporter-like protein (ZIP) family genes were conducted in the sampled Zn-deifcient leaves. The results showed that chlorophyl contents and net photosynthetic rate (Pn) seemed to decrease with reduced Zn contents. In addition, comparison of severe Zn-deifcient and normal leaves revealed that activities of peroxidase (POD) and catalase (CAT) increased signiifcantly, whereas that of Zn-containing enzymes such as Cu/Zn superoxide dismutase (Cu/Zn-SOD) signiifcantly reduced with decreasing Zn contents. As expected, expression of the ZIP family genes,ZIP1,ZIP3, andZIP4, was induced by Zn deifciencies. These results deepen our understanding of Zn deifciency in citrus plants as wel as provide useful preliminary information for further research.

  16. Comparison of gene expression in segregating families identifies genes and genomic regions involved in a novel adaptation, zinc hyperaccumulation.

    Science.gov (United States)

    Filatov, Victor; Dowdle, John; Smirnoff, Nicholas; Ford-Lloyd, Brian; Newbury, H John; Macnair, Mark R

    2006-09-01

    One of the challenges of comparative genomics is to identify specific genetic changes associated with the evolution of a novel adaptation or trait. We need to be able to disassociate the genes involved with a particular character from all the other genetic changes that take place as lineages diverge. Here we show that by comparing the transcriptional profile of segregating families with that of parent species differing in a novel trait, it is possible to narrow down substantially the list of potential target genes. In addition, by assuming synteny with a related model organism for which the complete genome sequence is available, it is possible to use the cosegregation of markers differing in transcription level to identify regions of the genome which probably contain quantitative trait loci (QTLs) for the character. This novel combination of genomics and classical genetics provides a very powerful tool to identify candidate genes. We use this methodology to investigate zinc hyperaccumulation in Arabidopsis halleri, the sister species to the model plant, Arabidopsis thaliana. We compare the transcriptional profile of A. halleri with that of its sister nonaccumulator species, Arabidopsis petraea, and between accumulator and nonaccumulator F(3)s derived from the cross between the two species. We identify eight genes which consistently show greater expression in accumulator phenotypes in both roots and shoots, including two metal transporter genes (NRAMP3 and ZIP6), and cytoplasmic aconitase, a gene involved in iron homeostasis in mammals. We also show that there appear to be two QTLs for zinc accumulation, on chromosomes 3 and 7.

  17. Comprehensive analysis of CCCH-type zinc finger gene family in citrus (Clementine mandarin) by genome-wide characterization.

    Science.gov (United States)

    Liu, Shengrui; Khan, Muhammad Rehman Gul; Li, Yongping; Zhang, Jinzhi; Hu, Chungen

    2014-10-01

    The CCCH-type zinc finger proteins comprise a large gene family of regulatory proteins and are widely distributed in eukaryotic organisms. The CCCH proteins have been implicated in multiple biological processes and environmental responses in plants. Little information is available, however, about CCCH genes in plants, especially in woody plants such as citrus. The release of the whole-genome sequence of citrus allowed us to perform a genome-wide analysis of CCCH genes and to compare the identified proteins with their orthologs in model plants. In this study, 62 CCCH genes and a total of 132 CCCH motifs were identified, and a comprehensive analysis including the chromosomal locations, phylogenetic relationships, functional annotations, gene structures and conserved motifs was performed. Distribution mapping revealed that 54 of the 62 CCCH genes are unevenly dispersed on the nine citrus chromosomes. Based on phylogenetic analysis and gene structural features, we constructed 5 subfamilies of 62 CCCH members and integrative subfamilies from citrus, Arabidopsis, and rice, respectively. Importantly, large numbers of SNPs and InDels in 26 CCCH genes were identified from Poncirus trifoliata and Fortunella japonica using whole-genome deep re-sequencing. Furthermore, citrus CCCH genes showed distinct temporal and spatial expression patterns in different developmental processes and in response to various stress conditions. Our comprehensive analysis of CleC3Hs is a valuable resource that further elucidates the roles of CCCH family members in plant growth and development. In addition, variants and comparative genomics analyses deepen our understanding of the evolution of the CCCH gene family and will contribute to further genetics and genomics studies of citrus and other plant species.

  18. A family for miniature, easily reconfigurable particle sensors for space plasma measurements

    Science.gov (United States)

    Wieser, M.; Barabash, S.

    2016-12-01

    Over the last 15 years the Swedish Institute of Space Physics developed a line of miniaturized ion mass analyzers for space plasma studies with masses of 400-600 g and highly compact and dense design to minimize the volume. The sensors cover an energy range from few eV up to 15 keV and reach an angular coverage up to hemispherical and mass resolution up to 7, depending on application. The experience with this line of sensors demonstrates that a sensor mass of 400-600 g is a limit in the trade-off between scientifically valuable performance and the sensor mass. The Solar Wind Monitor (SWIM), part of the Sub-keV Atom Reflecting Analyzer (SARA) on board of the Indian Chandrayaan-1 mission to the Moon, was the first sensor in the line. A number of instruments derived from SWIM were built, each using the same basic architecture but adapted for the needs of the corresponding mission: the Miniature Ion Precipitation Analyzer (MIPA) on the European Space Agency's BepiColombo mission to Mercury, the Detector for Ions at Mars (DIM) for the Russian Phobos-Grunt mission and the Yinghuo Plasma Package Ion sensor (YPPi) for the Chinese Yinghuo-1 spacecraft (both to Mars), the Prisma Ion Mass Analyzer (PRIMA) for the Swedish PRISMA spacecraft to Earth orbit, the eXtra Small Analyzer of Neutrals (XASN) for the Russian Luna-Glob lander, and the Laboratory Ion Scattering Analyzer (LISA) used for laboratory studies. We review architecture, design, performance, and fields of application of the instruments in this family and give and outlook in future developments.

  19. Genome-Wide Identification, Evolution and Expression Analysis of the Grape (Vitis vinifera L. Zinc Finger-Homeodomain Gene Family

    Directory of Open Access Journals (Sweden)

    Hao Wang

    2014-04-01

    Full Text Available Plant zinc finger-homeodomain (ZHD genes encode a family of transcription factors that have been demonstrated to play an important role in the regulation of plant growth and development. In this study, we identified a total of 13 ZHD genes (VvZHD in the grape genome that were further classified into at least seven groups. Genome synteny analysis revealed that a number of VvZHD genes were present in the corresponding syntenic blocks of Arabidopsis, indicating that they arose before the divergence of these two species. Gene expression analysis showed that the identified VvZHD genes displayed distinct spatiotemporal expression patterns, and were differentially regulated under various stress conditions and hormone treatments, suggesting that the grape VvZHDs might be also involved in plant response to a variety of biotic and abiotic insults. Our work provides insightful information and knowledge about the ZHD genes in grape, which provides a framework for further characterization of their roles in regulation of stress tolerance as well as other aspects of grape productivity.

  20. CCCH-type zinc finger family in maize: genome-wide identification, classification and expression profiling under abscisic acid and drought treatments.

    Directory of Open Access Journals (Sweden)

    Xiaojian Peng

    Full Text Available BACKGROUND: CCCH-type zinc finger proteins comprise a large protein family. Increasing evidence suggests that members of this family are RNA-binding proteins with regulatory functions in mRNA processing. Compared with those in animals, functions of CCCH-type zinc finger proteins involved in plant growth and development are poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: Here, we performed a genome-wide survey of CCCH-type zinc finger genes in maize (Zea mays L. by describing the gene structure, phylogenetic relationships and chromosomal location of each family member. Promoter sequences and expression profiles of putative stress-responsive members were also investigated. A total of 68 CCCH genes (ZmC3H1-68 were identified in maize and divided into seven groups by phylogenetic analysis. These 68 genes were found to be unevenly distributed on 10 chromosomes with 15 segmental duplication events, suggesting that segmental duplication played a major role in expansion of the maize CCCH family. The Ka/Ks ratios suggested that the duplicated genes of the CCCH family mainly experienced purifying selection with limited functional divergence after duplication events. Twelve maize CCCH genes grouped with other known stress-responsive genes from Arabidopsis were found to contain putative stress-responsive cis-elements in their promoter regions. Seven of these genes chosen for further quantitative real-time PCR analysis showed differential expression patterns among five representative maize tissues and over time in response to abscisic acid and drought treatments. CONCLUSIONS: The results presented in this study provide basic information on maize CCCH proteins and form the foundation for future functional studies of these proteins, especially for those members of which may play important roles in response to abiotic stresses.

  1. CCCH-type zinc finger family in maize: genome-wide identification, classification and expression profiling under abscisic acid and drought treatments.

    Science.gov (United States)

    Peng, Xiaojian; Zhao, Yang; Cao, Jiangang; Zhang, Wei; Jiang, Haiyang; Li, Xiaoyu; Ma, Qing; Zhu, Suwen; Cheng, Beijiu

    2012-01-01

    CCCH-type zinc finger proteins comprise a large protein family. Increasing evidence suggests that members of this family are RNA-binding proteins with regulatory functions in mRNA processing. Compared with those in animals, functions of CCCH-type zinc finger proteins involved in plant growth and development are poorly understood. Here, we performed a genome-wide survey of CCCH-type zinc finger genes in maize (Zea mays L.) by describing the gene structure, phylogenetic relationships and chromosomal location of each family member. Promoter sequences and expression profiles of putative stress-responsive members were also investigated. A total of 68 CCCH genes (ZmC3H1-68) were identified in maize and divided into seven groups by phylogenetic analysis. These 68 genes were found to be unevenly distributed on 10 chromosomes with 15 segmental duplication events, suggesting that segmental duplication played a major role in expansion of the maize CCCH family. The Ka/Ks ratios suggested that the duplicated genes of the CCCH family mainly experienced purifying selection with limited functional divergence after duplication events. Twelve maize CCCH genes grouped with other known stress-responsive genes from Arabidopsis were found to contain putative stress-responsive cis-elements in their promoter regions. Seven of these genes chosen for further quantitative real-time PCR analysis showed differential expression patterns among five representative maize tissues and over time in response to abscisic acid and drought treatments. The results presented in this study provide basic information on maize CCCH proteins and form the foundation for future functional studies of these proteins, especially for those members of which may play important roles in response to abiotic stresses.

  2. A cap-type Schiff base acting as a fluorescence sensor for zinc(II) and a colorimetric sensor for iron(II), copper(II), and zinc(II) in aqueous media.

    Science.gov (United States)

    Kim, Kyung Beom; Kim, Hyun; Song, Eun Joo; Kim, Sumi; Noh, Insup; Kim, Cheal

    2013-12-21

    A simple and low cost chemosensor is described. This sensor could simultaneously detect three biologically important metal ions through fluorogenic (Zn(2+)) and chromogenic (Fe(2+), Cu(2+), and Zn(2+)) methods in aqueous solution. The sensor could function as a "turn-on" fluorescence receptor only to Zn(2+) ions. In addition, the sensor could be successfully applied to the detection of intracellular Zn(2+). Meanwhile, the sensor displayed an obvious red color upon selective binding with Fe(2+). Therefore, the sensor could serve as a useful tool for the discrimination of Fe(2+) from Fe(3+) in aqueous media. Moreover, the sensor also showed color changes from yellow to colorless upon selective binding with Zn(2+) and Cu(2+), respectively. The detection limit of the sensor for Cu(2+) (1.5 μM) is far below the guidelines of the World Health Organization (30 μM) as the maximum allowable copper concentration in drinking water, and therefore it is capable of being a practical system for the monitoring of Cu(2+) concentrations in aqueous samples. These results provide a new approach for selectively recognizing the most important three trace elements in the human body simultaneously, for Zn(2+) by emission spectra and Fe(2+), Cu(2+), and Zn(2+) by the naked eye.

  3. The role of Zic family zinc finger transcription factors in the proliferation and differentiation of retinal progenitor cells

    Energy Technology Data Exchange (ETDEWEB)

    Watabe, Yui [Division of Molecular and Developmental Biology, Institute of Medical Science, University of Tokyo (Japan); Department of Ophthalmology, Teikyo University School of Medicine, Tokyo (Japan); Division of Orthoptics, Teikyo University School of Medical Care and Technology, Tokyo (Japan); Baba, Yukihiro [Division of Molecular and Developmental Biology, Institute of Medical Science, University of Tokyo (Japan); Nakauchi, Hiromitsu [Division of Stem Cell Therapy, Center for Stem Cell Biology and Regenerative Medicine, Institute of Medical Science, University of Tokyo (Japan); Mizota, Atsushi [Department of Ophthalmology, Teikyo University School of Medicine, Tokyo (Japan); Watanabe, Sumiko, E-mail: sumiko@ims.u-tokyo.ac.jp [Division of Molecular and Developmental Biology, Institute of Medical Science, University of Tokyo (Japan)

    2011-11-11

    Highlights: Black-Right-Pointing-Pointer Zic transcription factors expressed early retinal progenitor cells. Black-Right-Pointing-Pointer Zics sustain proliferation activity of retinal progenitor cells. Black-Right-Pointing-Pointer Overexpression of Zic in retinal progenitors perturbed rod differentiation. Black-Right-Pointing-Pointer Fate determination to rod photoreceptor was not affected. -- Abstract: Members of the Zic family of zinc finger transcription factors play critical roles in a variety of developmental processes. Using DNA microarray analysis, we found that Zics are strongly expressed in SSEA-1-positive early retinal progenitors in the peripheral region of the mouse retina. Reverse-transcription polymerase chain reaction using mRNA from the retina at various developmental stages showed that Zic1 and Zic2 are expressed in the embryonic retina and then gradually disappear during retinal development. Zic3 is also expressed in the embryonic retina; its expression level slightly decreases but it is expressed until adulthood. We overexpressed Zic1, Zic2, or Zic3 in retinal progenitors at embryonic day 17.5 and cultured the retina as explants for 2 weeks. The number of rod photoreceptors was fewer than in the control, but no other cell types showed significant differences between control and Zic overexpressing cells. The proliferation activity of normal retinal progenitors decreased after 5 days in culture, as observed in normal in vivo developmental processes. However, Zic expressing retinal cells continued to proliferate at days 5 and 7, suggesting that Zics sustain the proliferation activities of retinal progenitor cells. Since the effects of Zic1, 2, and 3 are indistinguishable in terms of differentiation and proliferation of retinal progenitors, the redundant function of Zics in retinal development is suggested.

  4. Transient Expression of Fez Family Zinc Finger 2 Protein Regulates the Brn3b Gene in Developing Retinal Ganglion Cells.

    Science.gov (United States)

    Qu, Chunsheng; Bian, Dandan; Li, Xue; Xiao, Jian; Wu, Chunping; Li, Yue; Jiang, Tian; Zhou, Xiangtian; Qu, Jia; Chen, Jie-Guang

    2016-04-01

    Retinal ganglion cells (RGCs) are projection neurons in the neural retina that relay visual information from the environment to the central nervous system. The early expression of MATH5 endows the post-mitotic precursors with RGC competence and leads to the activation ofBrn3bthat marks committed RGCs. Nevertheless, this fate commitment process and, specifically, regulation ofBrn3bremain elusive. To explore the molecular mechanisms underlying RGC generation in the mouse retina, we analyzed the expression and function of Fez family zinc finger 2 (FEZF2), a transcription factor critical for the development of projection neurons in the cerebral cortex.Fezf2mRNA and protein were transiently expressed at embryonic day 16.5 in the inner neuroblast layer and the prospective ganglion cell layer of the retina, respectively. Knockout ofFezf2in the developing retina reduced BRN3B+ cells and increased apoptotic cell markers.Fezf2knockdown by retinalin uteroelectroporation diminished BRN3B but not the coexpressed ISLET1 and BRN3A, indicating that the BRN3B decrease was the cause, not the result, of the overall reduction of BRN3B+ RGCs in theFezf2knockout retina. Moreover, the mRNA and promoter activity ofBrn3bwere increasedin vitroby FEZF2, which bound to a 5' regulatory fragment in theBrn3bgenomic locus. These results indicate that transient expression ofFezf2in the retina modulates the transcription ofBrn3band the survival of RGCs. This study improves our understanding of the transcriptional cascade required for the specification of RGCs and provides novel insights into the molecular basis of retinal development.

  5. Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, H. [PBI-Dansensor A/S (Denmark); Toft Soerensen, O. [Risoe National Lab., Materials Research Dept. (Denmark)

    1999-10-01

    A new type of ceramic oxygen sensors based on semiconducting oxides was developed in this project. The advantage of these sensors compared to standard ZrO{sub 2} sensors is that they do not require a reference gas and that they can be produced in small sizes. The sensor design and the techniques developed for production of these sensors are judged suitable by the participating industry for a niche production of a new generation of oxygen sensors. Materials research on new oxygen ion conducting conductors both for applications in oxygen sensors and in fuel was also performed in this project and finally a new process was developed for fabrication of ceramic tubes by dip-coating. (EHS)

  6. Sensors

    CERN Document Server

    Pigorsch, Enrico

    1997-01-01

    This is the 5th edition of the Metra Martech Directory "EUROPEAN CENTRES OF EXPERTISE - SENSORS." The entries represent a survey of European sensors development. The new edition contains 425 detailed profiles of companies and research institutions in 22 countries. This is reflected in the diversity of sensors development programmes described, from sensors for physical parameters to biosensors and intelligent sensor systems. We do not claim that all European organisations developing sensors are included, but this is a good cross section from an invited list of participants. If you see gaps or omissions, or would like your organisation to be included, please send details. The data base invites the formation of effective joint ventures by identifying and providing access to specific areas in which organisations offer collaboration. This issue is recognised to be of great importance and most entrants include details of collaboration offered and sought. We hope the directory on Sensors will help you to find the ri...

  7. Addressing the selectivity issue of cobalt doped zinc oxide thin film iso-butane sensors: Conductance transients and principal component analyses

    Science.gov (United States)

    Ghosh, A.; Majumder, S. B.

    2017-07-01

    Iso-butane (i-C4H10) is one of the major components of liquefied petroleum gas which is used as fuel in domestic and industrial applications. Developing chemi-resistive selective i-C4H10 thin film sensors remains a major challenge. Two strategies were undertaken to differentiate carbon monoxide, hydrogen, and iso-butane gases from the measured conductance transients of cobalt doped zinc oxide thin films. Following the first strategy, the response and recovery transients of conductances in these gas environments are fitted using the Langmuir adsorption kinetic model to estimate the heat of adsorption, response time constant, and activation energies for adsorption (response) and desorption (recovery). Although these test gases have seemingly different vapor densities, molecular diameters, and reactivities, analyzing the estimated heat of adsorption and activation energies (for both adsorption and desorption), we could not differentiate these gases unequivocally. However, we have found that the lower the vapor density, the faster the response time irrespective of the test gas concentration. As a second strategy, we demonstrated that feature extraction of conductance transients (using fast Fourier transformation) in conjunction with the pattern recognition algorithm (principal component analysis) is more fruitful to address the cross-sensitivity of Co doped ZnO thin film sensors. We have found that although the dispersion among different concentrations of hydrogen and carbon monoxide could not be avoided, each of these three gases forms distinct clusters in the plot of principal component 2 versus 1 and therefore could easily be differentiated.

  8. Characterization and phylogenetic analysis of environmental stress-responsive SAP gene family encoding A20/AN1 zinc finger proteins in tomato.

    Science.gov (United States)

    Solanke, Amolkumar U; Sharma, Manoj K; Tyagi, Akhilesh K; Sharma, Arun Kumar

    2009-08-01

    Characterization of genes responsive to stress is important for efforts on improving stress tolerance of plants. To address components involved in stress tolerance of tomato (Solanum lycopersicum), a stress-responsive gene family encoding A20/AN1 zinc finger proteins was characterized. In the present study, 13 members of this gene family were cloned from tomato cultivar Pusa Ruby and named as Stress Associated Protein (SAP) genes. Out of 13 genes, 12 have been mapped on their respective chromosomes. Expression of these genes in response to cold, heat, salt, desiccation, wounding, abscisic acid, oxidative and submergence stresses was analysed. All tomato SAP genes were found to be responsive to one or other type of environmental stress. The phylogenetic analysis of these genes, along with their orthologs from Solanaceae species suggests the presence of a common set of SAP genes in the studied Solanaceae species. The present study characterizes a SAP gene family, which encodes A20/AN1 zinc finger containing proteins from tomato for the first time. Genes showing high expression in response to a particular stress can be exploited for improving stress tolerance of tomato and other Solanaceae members.

  9. UV-Assisted Alcohol Sensors using Gallium Nitride Nanowires Functionalized with Zinc Oxide and Tin Dioxide Nanoparticles

    Science.gov (United States)

    Bajpai, Ritu

    The motivation behind this work has been to address two of the most challenging issues posed to semiconductor gas sensors--- tuning the device selectivity and sensitivity to a wide variety of gases. In a chemiresistor type nanowire sensor, the sensitivity and selectivity depend on the interaction of different chemical analytes with the nanowire surface. Constrained by the surface properties of the nanowire material, most nanowire sensors can detect only specific type of analytes. In order to make a nano-sensor array for a wide range of analytes, there is a need to tune the device sensitivity and selectivity towards different chemicals. Employing the inherent advantages of nanostructure based sensing such as large surface area, miniature size, low power consumption, and nmol/mol (ppb) sensitivity, an attempt has been made to propose a device with tunable selectivity and sensitivity. The idea proposed in this work is to functionalize GaN nanowires which have relatively inactive surface properties (i.e., with no chemiresistive sensitivity to different classes of organic vapors), with analyte dependent active metal oxides. The selectivity of the sensor devices is controlled independent of the surface properties of the nanowire itself. It is the surface properties of the functionalizing metal oxides which determine the selectivity of these sensors. Further facilitated by the proposed fabrication technique, these sensors can be easily tuned to detect different gases. The prototype developed in this work is that of a UV assisted alcohol sensor using GaN nanowires functionalized with ZnO and SnO2 nanoparticles. As opposed to the widely demonstrated metal oxide based sensors assisted by elevated temperature, the operation of photoconductive semiconductor sensor devices such as those fabricated in this work, can also be assisted by UV illumination at room temperature. Temperature assisted sensing requires an integrated on-chip heater, which could impose constraints on the

  10. 2,6-Bis(2-Benzimidazolyl)Pyridine Fluorescent Red-Shifted Sensor for Recognition of Zinc(II) and a Calorimetric Sensor for Iron Ions.

    Science.gov (United States)

    Vosough Razavi, Bita; Badiei, Alireza; Lashgari, Negar; Mohammadi Ziarani, Ghodsi

    2016-09-01

    The ability of 2,6-bis(2-benzimidazolyl)pyridine (bbp) as an optical sensor was studied by fluorescence spectroscopy, colorimetric and UV-visible techniques. The fluorescence spectra of bbp demonstrated a red-shifted upon addition of Zn(2+) ion, whereas rest of the cations did not induce any shift. Selectivity of the sensor was examined toward Zn(2+) in the presence of a wide range of cations, as interfering agents, that showed no disruption in its function. In addition, the pH effect was tested on the fluorescence response of bbp; which showed the efficiency of the sensor in a wide pH range. The limit of detection for Zn(2+) was estimated as 2.1 μM. Furthermore, the colorimetric studies were carried out and the observations showed a color change from colorless to purple by the addition of Fe(2+) ion and from colorless to yellow by the addition of Fe(3+). The UV-visible studies were carried out to confirm the colorimetric observations. The color changes occurred when Fe(2+) and Fe(3+) were added to the sensors solution, respectively. The detection limits were calculated as 2.8 × 10(-7) M and 3.5 × 10(-6) M for Fe(2+) and Fe(3+), respectively. Hence, bbp can be used as a dual mode optical sensor for detection of Zn(2+) by fluorescence and discriminately detection of Fe(2+) and Fe(3+) visually.

  11. A zinc-dependent protease AMZ-tk from a thermophilic archaeon is a new member of the archaemetzincin protein family

    Directory of Open Access Journals (Sweden)

    Baolei eJia

    2015-12-01

    Full Text Available A putative zinc-dependent protease (TK0512 in Thermococcus kodakarensis KOD1 shares a conserved motif with archaemetzincins, which are metalloproteases found in archaea, bacteria, and eukarya. Phylogenetic and sequence analyses showed that TK0512 and its homologues in Thermococcaceae represent new members in the archaemetzincins family, which we named AMZ-tk. We further confirmed its proteolytic activity biochemically by overexpression of the recombinant AMZ-tk in E. coli and characterization of the purified enzyme. In the presence of zinc, the purified enzyme degraded casein, while adding EDTA strongly inhibited the enzyme activity. AMZ-tk also exhibited self-cleavage activity that required Zn2+. These results demonstrated that AMZ-tk is a zinc-dependent protease within the archaemetzincin family. The enzyme displayed activity at alkaline pHs ranging from 7.0-10.0, with the optimal pH being 8.0. The optimum temperature for the catalytic activity of AMZ-tk was 55ºC. Quantitative reverse transcription-PCR revealed that transcription of AMZ-tk was also up-regulated after exposing the cells to 55 ºC and 65ºC. Mutant analysis suggests that Zn2+ binding histidine and catalytic glutamate plays key roles in proteolysis. AMZ-tk was thermostable on incubation for 4 h at 70°C in the presence of EDTA. AMZ-tk also retained >50% of its original activity in the presence of both laboratory surfactants and commercial laundry detergents. AMZ-tk further showed antibacterial activity against several bacteria. Therefore, AMZ-tk is of considerable interest for many purposes in view of its activity at alkaline pH, detergents, and thermostability.

  12. A low-symmetrical zinc phthalocyanine-based Langmuir-Blodgett thin films forNO2 gas sensor applications

    Science.gov (United States)

    Krichevsky, D. M.; Zasedatelev, A. V.; Tolbin, A. Yu; Zelenskiy, Yu M.; Krasovskii, V. I.; Karpo, A. B.; Tomilova, L. G.

    2016-08-01

    For many years effective detection of hazardous substances such as nitrogen oxides has remained a crucial task for environmental safety. In this article, we demonstrate high promising NO2-sensitive Langmuir-Blodgett monolayer structures based on 2-((2'- hydroxymethyl)-benzyloxy)-9(10),16(17),23(24)-tri-/re/-butyl- substituted low symmetrical zinc phthalocyanine complex bearing hydroxyl group on the periphery (compound 1). Amphiphilic arrangement of macrocycles was demonstrated to eliminate disordered molecular aggregation, resulting in a marked NO2 gas sensing effect under real atmospheric conditions. The optical response of monolayers was at room temperature, with the significant spectral changes being caused by the specific charge transfer process in phthalocyanine n-conjugated electronic system.

  13. A Family of Zinc Finger Proteins Is Required forChromosome-specific Pairing and Synapsis during Meiosis in C.elegans

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, Carolyn M.; Dernburg, Abby F.

    2006-06-07

    Homologous chromosome pairing and synapsis are prerequisitefor accurate chromosome segregation during meiosis. Here, we show that afamily of four related C2H2 zinc-finger proteins plays a central role inthese events in C. elegans. These proteins are encoded within a tandemgene cluster. In addition to the X-specific HIM-8 protein, threeadditional paralogs collectively mediate the behavior of the fiveautosomes. Each chromosome relies on a specific member of the family topair and synapse with its homolog. These "ZIM" proteins concentrate atspecial regions called meiotic pairing centers on the correspondingchromosomes. These sites are dispersed along the nuclear envelope duringearly meiotic prophase, suggesting a role analogous to thetelomere-mediated meiotic bouquet in other organisms. To gain insightinto the evolution of these components, wecharacterized homologs in C.briggsae and C. remanei, which revealed changes in copy number of thisgene family within the nematode lineage.

  14. Core-shell nanoparticles optical sensors - Rational design of zinc ions fluorescent nanoprobes of improved analytical performance

    Science.gov (United States)

    Woźnica, Emilia; Gasik, Joanna; Kłucińska, Katarzyna; Kisiel, Anna; Maksymiuk, Krzysztof; Michalska, Agata

    2017-10-01

    In this work the effect of affinity of an analyte to a receptor on the response of nanostructural fluorimetric probes is discussed. Core-shell nanoparticles sensors are prepared that benefit from the properties of the phases involved leading to improved analytical performance. The optical transduction system chosen is independent of pH, thus the change of sample pH can be used to control the analyte - receptor affinity through the ;conditional; binding constant prevailing within the lipophilic phase. It is shown that by affecting the ;conditional; binding constant the performance of the sensor can be fine-tuned. As expected, increase in ;conditional; affinity of the ligand embedded in the lipophilic phase to the analyte results in higher sensitivity over narrow concentration range - bulk reaction and sigmoidal shape response of emission intensity vs. logarithm of concentration changes. To induce a linear dependence of emission intensity vs. logarithm of analyte concentration covering a broad concentration range, a spatial confinement of the reaction zone is proposed, and application of core-shell nanostructures. The core material, polypyrrole nanospheres, is effectively not permeable for the analyte - ligand complex, thus the reaction is limited to the outer shell layer of the polymer prepared from poly(maleic anhydride-alt-1-octadecene). For herein introduced system a linear dependence of emission intensity vs. logarithm of Zn2+ concentration was obtained within the range from 10-7 to 10-1 M.

  15. Room-temperature phosphorescence sensor based on manganese doped zinc sulfide quantum dots for detection of urea

    Energy Technology Data Exchange (ETDEWEB)

    Bi, Lin; Dong, Xiang-ting; Yu, Yuan-hua, E-mail: jlyyh2013@126.com

    2014-09-15

    In this work, a simple scheme was proposed to prepare a urea-sensing system, which was composed of water-soluble Mn-doped ZnS phosphorescent QDs and urease. It allows for effective and quantitative detection of urea. The phosphorescence properties of MPA-capped Mn-doped ZnS QDs were explored to develop an RTP method for facile, rapid, cost-effective and selective detection of urea. This method does not need any deoxidant or other inducers and detects urea in biological fluids without being interfered from autofluorescence or the scattering light of the matrix. The new RTP sensor for urea detection has a detection limit of 0.014 mM and two linear ranges from 0 to 10 mM and from 10 to 60 mM. The precision for 11 replicate detections of 0.1 mM urea was 4.7%. The recoveries on spiked urine samples are 95–103%. It was successfully applied to the determination of urine without any complicated sample pretreatment. - Highlights: • RTP sensor greatly improves the urea detection ability. • The interferences from autofluorescence and scattering light were avoided. • The developed biosensor does not need any complicated sample pretreatment. • This method can be used to detect the content of urea in body fluid.

  16. A Comprehensive Catalog of Human KRAB-associated Zinc Finger Genes: Insights into the Evolutionary History of a Large Family of Transcriptional Repressors

    Energy Technology Data Exchange (ETDEWEB)

    Huntley, S; Baggott, D M; Hamilton, A T; Tran-Gyamfi, M; Yang, S; Kim, J; Gordon, L; Branscomb, E; Stubbs, L

    2005-09-30

    Krueppel-type zinc finger (ZNF) motifs are prevalent components of transcription factor proteins in all eukaryotic species. In mammals, most ZNF proteins comprise a single class of transcriptional repressors in which a chromatin interaction domain, called the Krueppel-associated box (KRAB) is attached to a tandem array of DNA-binding zinc-finger motifs. KRAB-ZNF loci are specific to tetrapod vertebrates, but have expanded dramatically in numbers through repeated rounds of segmental duplication to create a gene family with hundreds of members in mammals. To define the full repertoire of human KRAB-ZNF proteins, we searched the human genome for key motifs and used them to construct and manually curate gene models. The resulting KRAB-ZNF gene catalog includes 326 known genes, 243 of which were structurally corrected by manual annotation, and 97 novel KRAB-ZNF genes; this single family therefore comprises 20% of all predicted human transcription factor genes. Many of the genes are alternatively spliced, yielding a total of 743 distinct predicted proteins. Although many human KRAB-ZNF genes are conserved in mammals, at least 136 and potentially more than 200 genes of this type are primate-specific including many recent segmental duplicates. KRAB-ZNF genes are active in a wide variety of human tissues suggesting roles in many key biological processes, but most member genes remain completely uncharacterized. Because of their sheer numbers, wide-ranging tissue-specific expression patterns, and remarkable evolutionary divergence we predict that KRAB-ZNF transcription factors have played critical roles in crafting many aspects of human biology, including both deeply conserved and primate-specific traits.

  17. Polyvinyl chloride-based 18-crown-6, dibenzo18-crown-6 and calix-[6]-arene zinc(II-potentiometric sensors

    Directory of Open Access Journals (Sweden)

    Magda A. Akl

    2016-09-01

    Full Text Available Polyvinyl chloride (PVC based membranes of 18-crown-6 (18C6, dibenzo 18-crowen-6 (DB18C6 and calix[6]arene (CAX, as ionophores, with dioctylphenylphosphonate (DOPP, bis(ethylhexylsebacate (DOS dioctyl phthalate (DOP, 2-nitrophenyloctylether (o-NPOE and didecylphthalate (DDP as plasticizing solvent mediators are prepared and constructed for the determination of Zn(II. Of the 15 membranes constructed, only the PVC based membranes of DB18C6 and 18C6 ionophores with DOPP, as plasticizer, in the ratio (w/w PVC:ionophore:DOPP (60:2:120 give the best results in terms of working concentration range (1.0 × 10−5–1.0 × 10−1 M with a Nernstian slope of 29.0 mV/decade of activity for membrane composed of DOPP + DB18C6(1a and (1.0 × 10−5–1.0 × 10−1 M with a Nernstian slope of 30.0 mV/decade of activity for membrane composed of DOPP + 18C6(1b. The usable pH range of the sensors is 3.0–8.0, beyond which a drift in potential is observed. The response time of the sensors is ⩽15 s with a lifetime of 2 months during which they can be used without any measurable divergence. The selectivity coefficient values indicate that the electrode is highly selective for Zn2+ over a number of other cations except Pb2+ and Ag+. The electrodes have successfully been used to determine Zn(II in real alloys and standard samples with a precision as relative standard deviation (RSD <2% for each of the cited electrodes. The results obtained by the proposed ISEs are in good agreement with the results obtained by direct flame AAS method.

  18. ZINC-INDUCED FACILITATOR-LIKE family in plants: lineage-specific expansion in monocotyledons and conserved genomic and expression features among rice (Oryza sativa paralogs

    Directory of Open Access Journals (Sweden)

    Lopes Karina L

    2011-01-01

    Full Text Available Abstract Background Duplications are very common in the evolution of plant genomes, explaining the high number of members in plant gene families. New genes born after duplication can undergo pseudogenization, neofunctionalization or subfunctionalization. Rice is a model for functional genomics research, an important crop for human nutrition and a target for biofortification. Increased zinc and iron content in the rice grain could be achieved by manipulation of metal transporters. Here, we describe the ZINC-INDUCED FACILITATOR-LIKE (ZIFL gene family in plants, and characterize the genomic structure and expression of rice paralogs, which are highly affected by segmental duplication. Results Sequences of sixty-eight ZIFL genes, from nine plant species, were comparatively analyzed. Although related to MSF_1 proteins, ZIFL protein sequences consistently grouped separately. Specific ZIFL sequence signatures were identified. Monocots harbor a larger number of ZIFL genes in their genomes than dicots, probably a result of a lineage-specific expansion. The rice ZIFL paralogs were named OsZIFL1 to OsZIFL13 and characterized. The genomic organization of the rice ZIFL genes seems to be highly influenced by segmental and tandem duplications and concerted evolution, as rice genome contains five highly similar ZIFL gene pairs. Most rice ZIFL promoters are enriched for the core sequence of the Fe-deficiency-related box IDE1. Gene expression analyses of different plant organs, growth stages and treatments, both from our qPCR data and from microarray databases, revealed that the duplicated ZIFL gene pairs are mostly co-expressed. Transcripts of OsZIFL4, OsZIFL5, OsZIFL7, and OsZIFL12 accumulate in response to Zn-excess and Fe-deficiency in roots, two stresses with partially overlapping responses. Conclusions We suggest that ZIFL genes have different evolutionary histories in monocot and dicot lineages. In rice, concerted evolution affected ZIFL duplicated genes

  19. Electrochemical sensors for the simultaneous determination of zinc, cadmium and lead using a Nafion/ionic liquid/graphene composite modified screen-printed carbon electrode

    Energy Technology Data Exchange (ETDEWEB)

    Chaiyo, Sudkate [Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok (Thailand); Mehmeti, Eda [Institute of Chemistry, Department of Analytical Chemistry, Karl-Franzens University, Universitätsplatz 1, Graz A-8010 (Austria); Žagar, Kristina [Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana (Slovenia); Siangproh, Weena, E-mail: weena@swu.ac.th [Department of Chemistry, Faculty of Science, Srinakharinwirot University, Sukhumvit 23, Wattana, Bangkok (Thailand); Chailapakul, Orawon, E-mail: corawon@chula.ac.th [Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok (Thailand); Center of Excellence on Petrochemical and Materials Technology, Chulalongkorn University, Patumwan, Bangkok (Thailand); Kalcher, Kurt, E-mail: kurt.kalcher@uni-graz.at [Institute of Chemistry, Department of Analytical Chemistry, Karl-Franzens University, Universitätsplatz 1, Graz A-8010 (Austria)

    2016-04-28

    A simple, low cost, and highly sensitive electrochemical sensor, based on a Nafion/ionic liquid/graphene composite modified screen-printed carbon electrode (N/IL/G/SPCE) was developed to determine zinc (Zn(II)), cadmium (Cd(II)), and lead (Pb(II)) simultaneously. This disposable electrode shows excellent conductivity and fast electron transfer kinetics. By in situ plating with a bismuth film (BiF), the developed electrode exhibited well-defined and separate peaks for Zn(II), Cd(II), and Pb(II) by square wave anodic stripping voltammetry (SWASV). Analytical characteristics of the BiF/N/IL/G/SPCE were explored with calibration curves which were found to be linear for Zn(II), Cd(II), and Pb(II) concentrations over the range from 0.1 to 100.0 ng L{sup −1}. With an accumulation period of 120 s detection limits of 0.09 ng mL{sup −1}, 0.06 ng L{sup −1} and 0.08 ng L{sup −1} were obtained for Zn(II), Cd(II) and Pb(II), respectively using the BiF/N/IL/G/SPCE sensor, calculated as 3σ value of the blank. In addition, the developed electrode displayed a good repeatability and reproducibility. The interference from other common ions associated with Zn(II), Cd(II) and Pb(II) detection could be effectively avoided. Finally, the proposed analytical procedure was applied to detect the trace metal ions in drinking water samples with satisfactory results which demonstrates the suitability of the BiF/N/IL/G/SPCE to detect heavy metals in water samples and the results agreed well with those obtained by inductively coupled plasma mass spectrometry. - Highlights: • Nafion/ionic liquid/graphene composite modified electrode was fabricated. • Simultaneous determination of Zn, Cd and Pb in real samples was studied. • Zn, Cd and Pb could be sensitively measured as low as 90, 60 and 80 pg mL{sup −1}.

  20. A Zinc-Finger-Family Transcription Factor, AbVf19, Is Required for the Induction of a Gene Subset Important for Virulence in Alternaria brassicicola

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, Akhil [Univ. of Hawaii, Manoa, HI (United States); Ohm, Robin A. [USDOE Joint Genome Inst., Walnut Creek, CA (United States); Oxiles, Lindsay [Univ. of Hawaii, Manoa, HI (United States); Brooks, Fred [Univ. of Hawaii, Manoa, HI (United States); Lawrence, Christopher B. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Grigoriev, Igor V. [USDOE Joint Genome Inst., Walnut Creek, CA (United States); Cho, Yangrae [Univ. of Hawaii, Manoa, HI (United States)

    2011-10-26

    Alternaria brassicicola is a successful saprophyte and necrotrophic plant pathogen with a broad host range within the family Brassicaceae. It produces secondary metabolites that marginally affect virulence. Cell wall degrading enzymes (CDWE) have been considered important for pathogenesis but none of them individually have been identified as significant virulence factors in A. brassicicola. In this study, knockout mutants of a gene, AbVf19, were created and produced considerably smaller lesions than the wild type on inoculated host plants. The presence of tandem zinc-finger domains in the predicted amino acid sequence and nuclear localization of AbVf19- reporter protein suggested that it was a transcription factor. Gene expression comparisons using RNA-seq identified 74 genes being downregulated in the mutant during a late stage of infection. Among the 74 downregulated genes, 28 were putative CWDE genes. These were hydrolytic enzyme genes that composed a small fraction of genes within each family of cellulases, pectinases, cutinases, and proteinases. The mutants grew slower than the wild type on an axenic medium with pectin as a major carbon source. This study demonstrated the existence and the importance of a transcription factor that regulates a suite of genes that are important for decomposing and utilizing plant material during the late stage of plant infection.

  1. Assessment of plants from the Brassicaceae family as genetic models for the study of nickel and zinc hyperaccumulation.

    Science.gov (United States)

    Peer, Wendy Ann; Mahmoudian, Mehrzad; Freeman, John L; Lahner, Brett; Richards, Elizabeth L; Reeves, Roger D; Murphy, Angus S; Salt, David E

    2006-01-01

    We report on the second phase of a programme to select a relative of Arabidopsis thaliana for use in large-scale molecular genetic studies of nickel (Ni) and zinc (Zn) hyperaccumulation. We also report on the relatedness among Thlaspi caerulescens accessions and the utility of using O-acetyl-L-serine as a marker for Ni and Zn hyperaccumulation potential. Twenty-seven new accessions of metal-accumulating species collected in the Czech Republic, France, Greece, Italy, Slovenia and the USA during Spring-Summer 2002 were evaluated. The criteria established for selection were hyperaccumulation of metals (Ni and Zn); compact growth habit; reasonable time to flowering; production of > or = 1000 seeds per plant; self-fertility; compact diploid genome; high sequence similarity to A. thaliana; > or = 0.1% transformation efficiency with easy selection. We conclude that the best candidate identified in the first phase was the best candidate overall: T. caerulescens accession St Félix de Pallières.

  2. Toxicity and Removal of Zinc in the Three Species (Acutodesmus obliquus, Desmodesmus subspicatus and Desmodesmus armatus) Belonging to the Family, Scenedesmaceae (Chlorophyta)

    OpenAIRE

    Güçlü, Zekiye; Ömer Osman ERTAN

    2014-01-01

    In this study, the effects of zinc upon growth of three green microalgal species, Acutodesmus obliquus (Turpin) Hegewald & Hanagata, Desmodesmus subspicatus (Chodat) Hegewald & Schmidt and Desmodesmus armatus (Chodat) Hegewald, and the capability of these green algae for removal of zinc were investigated. Growth inhibition of the microalgal cells was determined following exposure for 96 h to five initial concentrations of zinc. The growth of the alga decreased wit h increa...

  3. Construction of a family of Cys2His2 zinc binding sites in the hydrophobic core of thioredoxin by structure-based design.

    Science.gov (United States)

    Wisz, M S; Garrett, C Z; Hellinga, H W

    1998-06-01

    A semi-automated, rational design strategy has been used to introduce a family of seven single, mononuclear Cys2His2 zinc sites at various locations in the hydrophobic core of Escherichia colithioredoxin, a protein that is normally devoid of metal centers. The electronic absorption spectra of the CoII complexes show that five of these designed proteins bind metal with the intended tetrahedral geometry. The designed sites differ in their metal-binding constants and effects on protein stability. Since these designs are constructed within the same host protein framework, comparison of their behavior allows a qualitative evaluation of dominant factors that contribute to metal-binding and metal-mediated protein stabilization. Metal-binding constants are dominated by steric interactions between the buried, designed coordination sphere and the surrounding protein matrix. Metal-mediated stability is the consequence of differential binding to the native and unfolded states. Increased interactions with the unfolded state decrease the stabilizing effect of metal binding. The affinity for the unfolded state is dependent on the placement of the primary coordination sphere residues within the linear protein sequence. These results indicate that a protein fold can have a remarkably broad potential for accommodating metal-mediated cross-links and suggest strategies for engineering protein stability by constructing metal sites that maximize metal binding to the native state and minimize binding to the unfolded state.

  4. Genome-wide analysis of the DNA-binding with one zinc finger (Dof) transcription factor family in bananas.

    Science.gov (United States)

    Dong, Chen; Hu, Huigang; Xie, Jianghui

    2016-12-01

    DNA-binding with one finger (Dof) domain proteins are a multigene family of plant-specific transcription factors involved in numerous aspects of plant growth and development. In this study, we report a genome-wide search for Musa acuminata Dof (MaDof) genes and their expression profiles at different developmental stages and in response to various abiotic stresses. In addition, a complete overview of the Dof gene family in bananas is presented, including the gene structures, chromosomal locations, cis-regulatory elements, conserved protein domains, and phylogenetic inferences. Based on the genome-wide analysis, we identified 74 full-length protein-coding MaDof genes unevenly distributed on 11 chromosomes. Phylogenetic analysis with Dof members from diverse plant species showed that MaDof genes can be classified into four subgroups (StDof I, II, III, and IV). The detailed genomic information of the MaDof gene homologs in the present study provides opportunities for functional analyses to unravel the exact role of the genes in plant growth and development.

  5. Zinc transporters and their role in the pancreatic β‐cell

    OpenAIRE

    Lemaire, Katleen; Chimienti, Fabrice; Schuit, Frans

    2012-01-01

    Abstract Zinc is an essential nutrient with tremendous importance for human health, and zinc deficiency is a severe risk factor for increased mortality and morbidity. As abnormal zinc homeostasis causes diabetes, and because the pancreatic β‐cell contains the highest zinc content of any known cell type, it is of interest to know how zinc fluxes are controlled in β‐cells. The understanding of zinc homeostasis has been boosted by the discovery of multiprotein families of zinc transporters, and ...

  6. Zinc alloy enhances strength and creep resistance

    Energy Technology Data Exchange (ETDEWEB)

    Machler, M. [Fisher Gauge Ltd., Peterborough, Ontario (Canada). Fishercast Div.

    1996-10-01

    A family of high-performance ternary zinc-copper-aluminum alloys has been developed that provides higher strength, hardness, and creep resistance than the traditional zinc-aluminum alloys Zamak 3, Zamak 5, and ZA-8. Designated ACuZinc, mechanical properties comparable to those of more expensive materials make it suitable for high-load applications and those at elevated temperatures. This article describes the alloy`s composition, properties, and historical development.

  7. MTF-1-mediated repression of the zinc transporter Zip10 is alleviated by zinc restriction.

    Directory of Open Access Journals (Sweden)

    Louis A Lichten

    Full Text Available The regulation of cellular zinc uptake is a key process in the overall mechanism governing mammalian zinc homeostasis and how zinc participates in cellular functions. We analyzed the zinc transporters of the Zip family in both the brain and liver of zinc-deficient animals and found a large, significant increase in Zip10 expression. Additionally, Zip10 expression decreased in response to zinc repletion. Moreover, isolated mouse hepatocytes, AML12 hepatocytes, and Neuro 2A cells also respond differentially to zinc availability in vitro. Measurement of Zip10 hnRNA and actinomycin D inhibition studies indicate that Zip10 was transcriptionally regulated by zinc deficiency. Through luciferase promoter constructs and ChIP analysis, binding of MTF-1 to a metal response element located 17 bp downstream of the transcription start site was shown to be necessary for zinc-induced repression of Zip10. Furthermore, zinc-activated MTF-1 causes down-regulation of Zip10 transcription by physically blocking Pol II movement through the gene. Lastly, ZIP10 is localized to the plasma membrane of hepatocytes and neuro 2A cells. Collectively, these results reveal a novel repressive role for MTF-1 in the regulation of the Zip10 zinc transporter expression by pausing Pol II transcription. ZIP10 may have roles in control of zinc homeostasis in specific sites particularly those of the brain and liver. Within that context ZIP10 may act as an important survival mechanism during periods of zinc inadequacy.

  8. Genome-wide identification, cloning and functional analysis of the Zinc/Iron-regulated transporter-like protein (ZIP) gene family in trifoliate orange (poncirus trifoliata L. Raf.)

    NARCIS (Netherlands)

    Fu, Xing Zheng; Zhou, Xue; Xing, Fei; Ling, Li Li; Chun, Chang Pin; Cao, Li; Aarts, Mark G.M.; Peng, Liang Zhi

    2017-01-01

    Zinc (Zn) and iron (Fe) deficiency are widespread among citrus plants, but the molecular mechanisms regarding uptake and transport of these two essential metal ions in citrus are still unclear. In the present study, 12 members of the Zn/Fe-regulated transporter (ZRT/IRT)-related protein (ZIP)

  9. Genome-wide identification, cloning and functional analysis of the Zinc/Iron-regulated transporter-like protein (ZIP) gene family in trifoliate orange (poncirus trifoliata L. Raf.)

    NARCIS (Netherlands)

    Fu, Xing Zheng; Zhou, Xue; Xing, Fei; Ling, Li Li; Chun, Chang Pin; Cao, Li; Aarts, Mark G.M.; Peng, Liang Zhi

    2017-01-01

    Zinc (Zn) and iron (Fe) deficiency are widespread among citrus plants, but the molecular mechanisms regarding uptake and transport of these two essential metal ions in citrus are still unclear. In the present study, 12 members of the Zn/Fe-regulated transporter (ZRT/IRT)-related protein (ZIP) gen

  10. NOVEL ZINC OXIDE FUNCTIONALIZED CARBON NANOTUBE CHEMIRESISTOR SENSOR ENHANCED WITH SURFACE O2 PLASMA INDUCED DEFECTS FOR METHANEDETECTION AT SINGLE PPM LEVEL

    Science.gov (United States)

    Novelty/Progress ClaimsThis paper presents a novel functionalized multi-walled carbon nanotubes (MWCNTs) based chemiresistor sensor which can detect methane at 2 ppm concentration level at room temperature with relative resistance change (RRC) of 2%. This is the highest reported ...

  11. NOVEL ZINC OXIDE FUNCTIONALIZED CARBON NANOTUBE CHEMIRESISTOR SENSOR ENHANCED WITH SURFACE O2 PLASMA INDUCED DEFECTS FOR METHANEDETECTION AT SINGLE PPM LEVEL

    Science.gov (United States)

    Novelty/Progress ClaimsThis paper presents a novel functionalized multi-walled carbon nanotubes (MWCNTs) based chemiresistor sensor which can detect methane at 2 ppm concentration level at room temperature with relative resistance change (RRC) of 2%. This is the highest reported ...

  12. On the Emerging Role of the Taste Receptor Type 1 (T1R Family of Nutrient-Sensors in the Musculoskeletal System

    Directory of Open Access Journals (Sweden)

    Shoichiro Kokabu

    2017-03-01

    Full Text Available The special sense of taste guides and guards food intake and is essential for body maintenance. Salty and sour tastes are sensed via ion channels or gated ion channels while G protein-coupled receptors (GPCRs of the taste receptor type 1 (T1R family sense sweet and umami tastes and GPCRs of the taste receptor type 2 (T2R family sense bitter tastes. T1R and T2R receptors share similar downstream signaling pathways that result in the stimulation of phospholipase-C-β2. The T1R family includes three members that form heterodimeric complexes to recognize either amino acids or sweet molecules such as glucose. Although these functions were originally described in gustatory tissue, T1R family members are expressed in numerous non-gustatory tissues and are now viewed as nutrient sensors that play important roles in monitoring global glucose and amino acid status. Here, we highlight emerging evidence detailing the function of T1R family members in the musculoskeletal system and review these findings in the context of the musculoskeletal diseases sarcopenia and osteoporosis, which are major public health problems among the elderly that affect locomotion, activities of daily living, and quality of life. These studies raise the possibility that T1R family member function may be modulated for therapeutic benefit.

  13. On the Emerging Role of the Taste Receptor Type 1 (T1R) Family of Nutrient-Sensors in the Musculoskeletal System.

    Science.gov (United States)

    Kokabu, Shoichiro; Lowery, Jonathan W; Toyono, Takashi; Sato, Tsuyoshi; Yoda, Tetsuya

    2017-03-15

    The special sense of taste guides and guards food intake and is essential for body maintenance. Salty and sour tastes are sensed via ion channels or gated ion channels while G protein-coupled receptors (GPCRs) of the taste receptor type 1 (T1R) family sense sweet and umami tastes and GPCRs of the taste receptor type 2 (T2R) family sense bitter tastes. T1R and T2R receptors share similar downstream signaling pathways that result in the stimulation of phospholipase-C-β2. The T1R family includes three members that form heterodimeric complexes to recognize either amino acids or sweet molecules such as glucose. Although these functions were originally described in gustatory tissue, T1R family members are expressed in numerous non-gustatory tissues and are now viewed as nutrient sensors that play important roles in monitoring global glucose and amino acid status. Here, we highlight emerging evidence detailing the function of T1R family members in the musculoskeletal system and review these findings in the context of the musculoskeletal diseases sarcopenia and osteoporosis, which are major public health problems among the elderly that affect locomotion, activities of daily living, and quality of life. These studies raise the possibility that T1R family member function may be modulated for therapeutic benefit.

  14. Familial Amyotrophic Lateral Sclerosis-associated Mutations Decrease the Thermal Stability of Distinctly Metallated Species of Human Copper/Zinc Superoxide Dismutase

    National Research Council Canada - National Science Library

    Jorge A. Rodriguez; Joan S. Valentine; Daryl K. Eggers; James A. Roe; Ashutosh Tiwari; Robert H. Brown, Jr; Lawrence J. Hayward

    2002-01-01

    ...) associated with familial amyotrophic lateral sclerosis (FALS). Multiple endothermic unfolding transitions were observed by differential scanning calorimetry for partially metallated SOD1 enzymes isolated from a baculovirus system...

  15. Effects of exogenous zinc on cell cycle, apoptosis and viability of MDAMB231, HepG2 and 293 T cells.

    Science.gov (United States)

    Wang, Yan-hong; Li, Ke-jin; Mao, Li; Hu, Xin; Zhao, Wen-jie; Hu, An; Lian, Hong-zhen; Zheng, Wei-juan

    2013-09-01

    As a non-toxic metal to humans, zinc is essential for cell proliferation, differentiation, regulation of DNA synthesis, genomic stability and mitosis. Zinc homeostasis in cells, which is crucial for normal cellular functioning, is maintained by various protein families including ZnT (zinc transporter/SLC30A) and ZIP (Zrt-, Irt-like proteins/SLC39A) that decrease and increase cytosolic zinc availability, respectively. In this study, we investigated the influences of a specific concentration range of ZnSO4 on cell cycle and apoptosis by flow cytometry, and cell viability by MTT method in MDAMB231, HepG2 and 293 T cell lines. Fluorescent sensors NBD-TPEA and the counterstain for nuclei Hoechst 33342 were used to stain the treated cells for observing the localisation and amount of Zn(2+) via laser scanning confocal microscope. It was found that the influence manners of ZnSO4 on cell cycle, apoptosis and cell viability in various cell lines were different and corresponding to the changes of Zn(2+) content of the three cell lines, respectively. The significant increase on intracelluar zinc content of MDAMB231 cells resulted in cell death, G1 and G2/M cell cycle arrest and increased apoptotic fraction. Additionally, the mRNA expression levels of ZnT and ZIP families in the three cell lines, when treated with high concentration of ZnSO4, increased and decreased corresponding to their functions, respectively.

  16. Integrated criteria document Zinc

    NARCIS (Netherlands)

    Cleven RFMJ; Janus JA; Annema JA; Slooff W

    1993-01-01

    This report contains information on zinc and zinc compounds concerning standards, emissions, exposure levels and effect levels. It includes a risk evaluation and presents proposals for maximum permissible concentrations of zinc in the environment. This study indicates that the concentration of zinc

  17. Genetic causes and gene–nutrient interactions in mammalian zinc deficiencies: acrodermatitis enteropathica and transient neonatal zinc deficiency as examples.

    Science.gov (United States)

    Kasana, Shakhenabat; Din, Jamila; Maret, Wolfgang

    2015-01-01

    Discovering genetic causes of zinc deficiency has been a remarkable scientific journey. It started with the description of a rare skin disease, its treatment with various agents, the successful therapy with zinc, and the identification of mutations in a zinc transporter causing the disease. The journey continues with defining the molecular and cellular pathways that lead to the symptoms caused by zinc deficiency. Remarkably, at least two zinc transporters from separate protein families are now known to be involved in the genetics of zinc deficiency. One is ZIP4, which is involved in intestinal zinc uptake. Its mutations can cause acrodermatitis enteropathica (AE) with autosomal recessive inheritance. The other one is ZnT2, the transporter responsible for supplying human milk with zinc. Mutations in this transporter cause transient neonatal zinc deficiency (TNZD) with symptoms similar to AE but with autosomal dominant inheritance. The two diseases can be distinguished in affected infants. AE is fatal if zinc is not supplied to the infant after weaning, whereas TNZD is a genetic defect of the mother limiting the supply of zinc in the milk, and therefore the infant usually will obtain enough zinc once weaned. Although these diseases are relatively rare, the full functional consequences of the numerous mutations in ZIP4 and ZnT2 and their interactions with dietary zinc are not known. In particular, it remains unexplored whether some mutations cause milder disease phenotypes or increase the risk for other diseases if dietary zinc requirements are not met or exceeded. Thus, it is not known whether widespread zinc deficiency in human populations is based primarily on a nutritional deficiency or determined by genetic factors as well. This consideration becomes even more significant with regard to mutations in the other 22 human zinc transporters, where associations with a range of diseases, including diabetes, heart disease, and mental illnesses have been observed

  18. Update on zinc biology.

    Science.gov (United States)

    Solomons, Noel W

    2013-01-01

    Zinc has become a prominent nutrient of clinical and public health interest in the new millennium. Functions and actions for zinc emerge as increasingly ubiquitous in mammalian anatomy, physiology and metabolism. There is undoubtedly an underpinning in fundamental biology for all of the aspects of zinc in human health (clinical and epidemiological) in pediatric and public health practice. Unfortunately, basic science research may not have achieved a full understanding as yet. As a complement to the applied themes in the companion articles, a selection of recent advances in the domains homeostatic regulation and transport of zinc is presented; they are integrated, in turn, with findings on genetic expression, intracellular signaling, immunity and host defense, and bone growth. The elements include ionic zinc, zinc transporters, metallothioneins, zinc metalloenzymes and zinc finger proteins. In emerging basic research, we find some plausible mechanistic explanations for delayed linear growth with zinc deficiency and increased infectious disease resistance with zinc supplementation. Copyright © 2013 S. Karger AG, Basel.

  19. Zinc stannate nanostructures: hydrothermal synthesis

    Directory of Open Access Journals (Sweden)

    Sunandan Baruah and Joydeep Dutta

    2011-01-01

    Full Text Available Nanostructured binary semiconducting metal oxides have received much attention in the last decade owing to their unique properties rendering them suitable for a wide range of applications. In the quest to further improve the physical and chemical properties, an interest in ternary complex oxides has become noticeable in recent times. Zinc stannate or zinc tin oxide (ZTO is a class of ternary oxides that are known for their stable properties under extreme conditions, higher electron mobility compared to its binary counterparts and other interesting optical properties. The material is thus ideal for applications from solar cells and sensors to photocatalysts. Among the different methods of synthesizing ZTO nanostructures, the hydrothermal method is an attractive green process that is carried out at low temperatures. In this review, we summarize the conditions leading to the growth of different ZTO nanostructures using the hydrothermal method and delve into a few of its applications reported in the literature.

  20. Method of capturing or trapping zinc using zinc getter materials

    Energy Technology Data Exchange (ETDEWEB)

    Hunyadi Murph, Simona E.; Korinko, Paul S.

    2017-07-11

    A method of trapping or capturing zinc is disclosed. In particular, the method comprises a step of contacting a zinc vapor with a zinc getter material. The zinc getter material comprises nanoparticles and a metal substrate.

  1. Zinc: the neglected nutrient.

    Science.gov (United States)

    Shambaugh, G E

    1989-03-01

    Zinc was first recognized as essential for animals at the University of Illinois School of Agriculture in 1916, when it was found that zinc-deficient baby pigs were runty, developed dermatitis on their legs, and were sterile. Zinc deficiency was first recognized in man by Dr. Ananda Prasad of Detroit 26 years ago when he measured serum and hair zinc levels in young male Egyptian dwarfs who had failed to mature and were small in stature. By simply adding zinc to their regular diet, they grew in height and became sexually mature. It is now recognized that dwarfism in males is frequent around the Mediterranean, where wheat is the staple of life and has been grown for 4,000 years on the same soil, thereby resulting in the depletion of zinc. Professor Robert Henkin first suggested that zinc deficiency might cause hearing-nerve impairment. Assay of the soft tissues of the cochlea and vestibule revealed a zinc level higher than that of any other part of the body. Previously, the eye was considered to have the highest level of zinc of any organ. To diagnose zinc deficiency clinically, we use serum zinc assays made at the Mayo Clinic Trace Element Laboratory. With zinc supplementation in patients who are marginally zinc deficient, there has been improvement in tinnitus and sensorineural hearing loss in about one-third of elderly adults. We believe zinc deficiency is one causation of presbycusis; by recognizing and correcting it, a progressive hearing loss can be arrested.

  2. The Essential Toxin: Impact of Zinc on Human Health

    Directory of Open Access Journals (Sweden)

    Laura M. Plum

    2010-03-01

    Full Text Available Compared to several other metal ions with similar chemical properties, zinc is relatively harmless. Only exposure to high doses has toxic effects, making acute zinc intoxication a rare event. In addition to acute intoxication, long-term, high-dose zinc supplementation interferes with the uptake of copper. Hence, many of its toxic effects are in fact due to copper deficiency. While systemic homeostasis and efficient regulatory mechanisms on the cellular level generally prevent the uptake of cytotoxic doses of exogenous zinc, endogenous zinc plays a significant role in cytotoxic events in single cells. Here, zinc influences apoptosis by acting on several molecular regulators of programmed cell death, including caspases and proteins from the Bcl and Bax families. One organ where zinc is prominently involved in cell death is the brain, and cytotoxicity in consequence of ischemia or trauma involves the accumulation of free zinc. Rather than being a toxic metal ion, zinc is an essential trace element. Whereas intoxication by excessive exposure is rare, zinc deficiency is widespread and has a detrimental impact on growth, neuronal development, and immunity, and in severe cases its consequences are lethal. Zinc deficiency caused by malnutrition and foods with low bioavailability, aging, certain diseases, or deregulated homeostasis is a far more common risk to human health than intoxication.

  3. Zinc oxide overdose

    Science.gov (United States)

    Zinc oxide is an ingredient in many products. Some of these are certain creams and ointments used ... prevent or treat minor skin burns and irritation. Zinc oxide overdose occurs when someone eats one of ...

  4. Model of how plants sense zinc deficiency

    DEFF Research Database (Denmark)

    Assuncao, Ana G.L.; Persson, Daniel Olof; Husted, Søren;

    2013-01-01

    to develop plant-based solutions addressing nutrient-use-efficiency and adaptation to nutrient-limited or -toxic soils. Recently two transcription factors of the bZIP family (basic-region leucine zipper) have been identified in Arabidopsis and shown to be pivotal in the adaptation response to zinc deficiency....... They represent not only the first regulators of zinc homeostasis identified in plants, but also a very promising starting-point that can provide new insights into the molecular basis of how plants sense and adapt to the stress of zinc deficiency. Considering the available information thus far we propose...... in this review a putative model of how plants sense zinc deficiency....

  5. A new family of field-stable and highly sensitive SQUID current sensors based on sub-micrometer cross-type Josephson junctions

    Science.gov (United States)

    Schmelz, M.; Zakosarenko, V.; Schönau, T.; Anders, S.; Kunert, J.; Meyer, M.; Meyer, H.-G.; Stolz, R.

    2017-07-01

    We report on the development of a new family of superconducting quantum interference device (SQUID) current sensors based on sub-micron cross-type Josephson tunnel junctions. Their low total junction capacitance permits high usable voltage swings of more than 100 μV and exceptional low noise of the SQUIDs at 4.2 K. Integrated rf-filters as well as high tolerable background fields during cool-down of up to 9.6 mT enable their highly reliable and easy use. With input coil inductances ranging from 10 nH to 2.8 μH and current sensitivities and coupled energy resolution down to 65 fA Hz-1/2 and below 10 h, respectively, they are a versatile tool for numerous applications.

  6. Zinc and zinc transporters in macrophages and their roles in efferocytosis in COPD.

    Directory of Open Access Journals (Sweden)

    Rhys Hamon

    Full Text Available Our previous studies have shown that nutritional zinc restriction exacerbates airway inflammation accompanied by an increase in caspase-3 activation and an accumulation of apoptotic epithelial cells in the bronchioles of the mice. Normally, apoptotic cells are rapidly cleared by macrophage efferocytosis, limiting any secondary necrosis and inflammation. We therefore hypothesized that zinc deficiency is not only pro-apoptotic but also impairs macrophage efferocytosis. Impaired efferocytic clearance of apoptotic epithelial cells by alveolar macrophages occurs in chronic obstructive pulmonary disease (COPD, cigarette-smoking and other lung inflammatory diseases. We now show that zinc is a factor in impaired macrophage efferocytosis in COPD. Concentrations of zinc were significantly reduced in the supernatant of bronchoalveolar lavage fluid of patients with COPD who were current smokers, compared to healthy controls, smokers or COPD patients not actively smoking. Lavage zinc was positively correlated with AM efferocytosis and there was decreased efferocytosis in macrophages depleted of Zn in vitro by treatment with the membrane-permeable zinc chelator TPEN. Organ and cell Zn homeostasis are mediated by two families of membrane ZIP and ZnT proteins. Macrophages of mice null for ZIP1 had significantly lower intracellular zinc and efferocytosis capability, suggesting ZIP1 may play an important role. We investigated further using the human THP-1 derived macrophage cell line, with and without zinc chelation by TPEN to mimic zinc deficiency. There was no change in ZIP1 mRNA levels by TPEN but a significant 3-fold increase in expression of another influx transporter ZIP2, consistent with a role for ZIP2 in maintaining macrophage Zn levels. Both ZIP1 and ZIP2 proteins were localized to the plasma membrane and cytoplasm in normal human lung alveolar macrophages. We propose that zinc homeostasis in macrophages involves the coordinated action of ZIP1 and ZIP2

  7. Zinc Deficiency Impacts CO2 Assimilation and Disrupts Copper Homeostasis in Chlamydomonas reinhardtii*

    Science.gov (United States)

    Malasarn, Davin; Kropat, Janette; Hsieh, Scott I.; Finazzi, Giovanni; Casero, David; Loo, Joseph A.; Pellegrini, Matteo; Wollman, Francis-André; Merchant, Sabeeha S.

    2013-01-01

    Zinc is an essential nutrient because of its role in catalysis and in protein stabilization, but excess zinc is deleterious. We distinguished four nutritional zinc states in the alga Chlamydomonas reinhardtii: toxic, replete, deficient, and limited. Growth is inhibited in zinc-limited and zinc-toxic cells relative to zinc-replete cells, whereas zinc deficiency is visually asymptomatic but distinguished by the accumulation of transcripts encoding ZIP family transporters. To identify targets of zinc deficiency and mechanisms of zinc acclimation, we used RNA-seq to probe zinc nutrition-responsive changes in gene expression. We identified genes encoding zinc-handling components, including ZIP family transporters and candidate chaperones. Additionally, we noted an impact on two other regulatory pathways, the carbon-concentrating mechanism (CCM) and the nutritional copper regulon. Targets of transcription factor Ccm1 and various CAH genes are up-regulated in zinc deficiency, probably due to reduced carbonic anhydrase activity, validated by quantitative proteomics and immunoblot analysis of Cah1, Cah3, and Cah4. Chlamydomonas is therefore not able to grow photoautotrophically in zinc-limiting conditions, but supplementation with 1% CO2 restores growth to wild-type rates, suggesting that the inability to maintain CCM is a major consequence of zinc limitation. The Crr1 regulon responds to copper limitation and is turned on in zinc deficiency, and Crr1 is required for growth in zinc-limiting conditions. Zinc-deficient cells are functionally copper-deficient, although they hyperaccumulate copper up to 50-fold over normal levels. We suggest that zinc-deficient cells sequester copper in a biounavailable form, perhaps to prevent mismetallation of critical zinc sites. PMID:23439652

  8. Molecular Cloning and Expression Analysis of a Cys2/His2 Type Zinc Finger Protein Gene in Upland Cotton

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The zinc finger proteins belong to the largest family of transcription factors.But there is little research of Cys2/His2 type zinc finger proteins in cotton,and there is no submission of correlating ESTs

  9. Time-resolved fluorescence spectroscopy for chemical sensors

    Science.gov (United States)

    Draxler, Sonja; Lippitsch, Max E.

    1996-07-01

    A family of sensors is presented with fluorescence decay-time measurements used as the sensing technique. The concept is to take a single fluorophore with a suitably long fluorescence decay time as the basic building block for numerous different sensors. Analyte recognition can be performed by different functional groups that are necessary for selective interaction with the analyte. To achieve this, the principle of excited-state electron transfer is applied with pyrene as the fluorophore. Therefore the same instrumentation based on a small, ambient air-nitrogen laser and solid-state electronics can be used to measure different analytes, for example, oxygen, pH, carbon dioxide, potassium, ammonium, lead, cadmium, zinc, and phosphate.

  10. Cadmium and zinc relationships

    Energy Technology Data Exchange (ETDEWEB)

    Elinder, C.; Piscator, M.

    1978-08-01

    Higher mammals, such as homo sapiens, accumulate zinc in kidney cortex almost equimolarly with cadmium. A different pattern seems to be present in liverthere is a limited increase of zinc in two species of large farm animals compared with a marked increase in the laboratory. In large farm animals, an equimolar increase of zinc with cadmium in renal cortex seems to indicate that the form of metallothionein that binds equal amounts of cadmium and zinc in present. Differences in cadmium and zinc relationships in large animals and humans compared with laboratory animals must be carefully considered. (4 graphs, 26 references)

  11. CO2 gas sensitivity of sputtered zinc oxide thin films

    Indian Academy of Sciences (India)

    P Samarasekara; N U S Yapa; N T R N Kumara; M V K Perera

    2007-04-01

    For the first time, sputtered zinc oxide (ZnO) thin films have been used as a CO2 gas sensor. Zinc oxide thin films have been synthesized using reactive d.c. sputtering method for gas sensor applications, in the deposition temperature range from 130–153°C at a chamber pressure of 8.5 mbar for 18 h. Argon and oxygen gases were used as sputtering and reactive gases, respectively. ZnO phase could be crystallized using a pure metal target of zinc. The structure of the films determined by means of X-ray diffraction method indicates that the zinc oxide single phase can be fabricated in this substrate temperature range. The sensitivity of the film synthesized at substrate temperature of 130°C is 2.17 in the presence of CO2 gas at a measuring temperature of 100°C.

  12. Zinc and skin biology.

    Science.gov (United States)

    Ogawa, Youichi; Kawamura, Tatsuyoshi; Shimada, Shinji

    2016-12-01

    Of all tissues, the skin has the third highest abundance of zinc in the body. In the skin, the zinc concentration is higher in the epidermis than in the dermis, owing to a zinc requirement for the active proliferation and differentiation of epidermal keratinocytes. Here we review the dynamics and functions of zinc in the skin as well as skin disorders associated with zinc deficiency, zinc finger domain-containing proteins, and zinc transporters. Among skin disorders associated with zinc deficiency, acrodermatitis enteropathica is a disorder caused by mutations in the ZIP4 transporter and subsequent zinc deficiency. The triad acrodermatitis enteropathica is characterized by alopecia, diarrhea, and skin lesions in acral, periorificial, and anogenital areas. We highlight the underlying mechanism of the development of acrodermatitis because of zinc deficiency by describing our new findings. We also discuss the accumulating evidence on zinc deficiency in alopecia and necrolytic migratory erythema, which is typically associated with glucagonomas. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Cadmium and zinc relationships.

    Science.gov (United States)

    Elinder, C G; Piscator, M

    1978-08-01

    Cadmium and zinc concentrations in kidney and liver have been measured under different exposure situations in different species including man. The results show that zinc increases almost equimolarly with cadmium in kidney after long-term low-level exposure to cadmium, e.g., in man, horse, pig, and lamb. In contrast, the increase of zinc follows that of cadmium to only a limited extent, e.g., in guinea pig, rabbit, rat, mouse, and chicks. In liver, the cadmium--zinc relationship seems to be reversed in such a way that zinc increases with cadmium more markedly in laboratory animals than in higher mammals. These differences between cadmium and zinc relationships in humans and large farm animals and those in commonly used laboratory animals must be considered carefully before experimental data on cadmium and zinc relationships in laboratory animals can be extrapolated to humans.

  14. Identification of the Human Zinc Transcriptional Regulatory Element (ZTRE)

    Science.gov (United States)

    Coneyworth, Lisa J.; Jackson, Kelly A.; Tyson, John; Bosomworth, Helen J.; van der Hagen, Eline; Hann, Georgia M.; Ogo, Ogo A.; Swann, Daniel C.; Mathers, John C.; Valentine, Ruth A.; Ford, Dianne

    2012-01-01

    Many genes with crucial roles in zinc homeostasis in mammals respond to fluctuating zinc supply through unknown mechanisms, and uncovering these mechanisms is essential to understanding the process at cellular and systemic levels. We detected zinc-dependent binding of a zinc-induced protein to a specific sequence, the zinc transcriptional regulatory element (ZTRE), in the SLC30A5 (zinc transporter ZnT5) promoter and showed that substitution of the ZTRE abrogated the repression of a reporter gene in response to zinc. We identified the ZTRE in other genes, including (through an unbiased search) the CBWD genes and (through targeted analysis) in multiple members of the SLC30 family, including SLC30A10, which is repressed by zinc. The function of the CBWD genes is currently unknown, but roles for homologs in metal homeostasis are being uncovered in bacteria. We demonstrated that CBWD genes are repressed by zinc and that substitution of the ZTRE in SLC30A10 and CBWD promoter-reporter constructs abrogates this response. Other metals did not affect expression of the transcriptional regulator, binding to the ZTRE or promoter-driven reporter gene expression. These findings provide the basis for elucidating how regulation of a network of genes through this novel mechanism contributes to zinc homeostasis and how the cell orchestrates this response. PMID:22902622

  15. Genome wide identification, phylogeny and expression of zinc transporter genes in common carp.

    Directory of Open Access Journals (Sweden)

    Yanliang Jiang

    Full Text Available BACKGROUND: Zinc is an essential trace element in organisms, which serves as a cofactor for hundreds of enzymes that are involved in many pivotal biological processes including growth, development, reproduction and immunity. Therefore, the homeostasis of zinc in the cell is fundamental. The zinc transporter gene family is a large gene family that encodes proteins which regulate the movement of zinc across cellular and intracellular membranes. However, studies on teleost zinc transporters are mainly limited to model species. METHODOLOGY/PRINCIPAL FINDINGS: We identified a set of 37 zinc transporters in common carp genome, including 17 from SLC30 family (ZnT, and 20 from SLC39 family (ZIP. Phylogenetic and syntenic analysis revealed that most of the zinc transporters are highly conserved, though recent gene duplication and gene losses do exist. Through examining the copy number of zinc transporter genes across several vertebrate genomes, thirteen zinc transporters in common carp are found to have undergone the gene duplications, including SLC30A1, SLC30A2, SLC30A5, SLC30A7, SLC30A9, SLC30A10, SLC39A1, SLC39A3, SLC39A4, SLC39A5, SLC39A6, SLC39A7 and SLC39A9. The expression patterns of all zinc transporters were established in various tissues, including blood, brain, gill, heart, intestine, liver, muscle, skin, spleen and kidney, and showed that most of the zinc transporters were ubiquitously expressed, indicating the critical role of zinc transporters in common carp. CONCLUSIONS: To some extent, examination of gene families with detailed phylogenetic or orthology analysis could verify the authenticity and accuracy of assembly and annotation of the recently published common carp whole genome sequences. The gene families are also considered as a unique source for evolutionary studies. Moreover, the whole set of common carp zinc transporters provides an important genomic resource for future biochemical, toxicological and physiological studies of zinc

  16. Sensors for Process Control

    Science.gov (United States)

    Tschulena, G.

    1988-01-01

    Sensors are one of the key elements for the automation in the manufacturing and process technology. The sensor field is presently within a restructuring process, directed to a stronger utilization of solid state technologies. This restructuring is governed by the utilization of solid state physical effects, by the use of reproducible fabrication techniques, and by the market driving forces. The state of the art of sensors in modern fabrication techniques will be demonstrated in examples, namely for sensors in silicon technology, in thin film technology and in thick film/screen printing technology. Some important physical and technological problems to be solved for the development of new and advanced sensor families will be outlined. Sensor development is strongly directed to the minaturization of devices and to the integration of different sensors to multisensors, as well as the integration between sensors and microelectronics.

  17. Use of Specific Properties of Zinc Ferrite in Innovative Technologies

    Directory of Open Access Journals (Sweden)

    Kmita A.

    2016-12-01

    Full Text Available Zinc ferrite ZnFe2O4 both in the micro and nano scale is widely used in various fields. The article discusses the structure of this compound and its properties in the nanoscale, which is clearly different from those which the ferrite shows in the microscale. The properties of dust generated electric arc furnace, which can contain up to 40% zinc, substantially in the form of ZnFe2O4 are disscused here. Specific properties (electric, magnetic, thermal of zinc ferrite nanoparticles determine the very wide possibilities of their use, inter alia as catalysts, absorbents, gas sensors, and a tool to combat cancer.

  18. Wild fire impact on copper, zinc, lead and cadmium distribution in soil and relation with abundance in selected plants of Lamiaceae family from Vidlic Mountain (Serbia).

    Science.gov (United States)

    Stankov Jovanovic, V P; Ilic, M D; Markovic, M S; Mitic, V D; Nikolic Mandic, S D; Stojanovic, G S

    2011-09-01

    Fire has been considered as an improving factor in soil quality, but only if it is controlled. Severe wild fire occurred in the summer 2007 on the Vidlic Mountain (Serbia) overspreading a huge area of meadows and forests. Main soil characteristics and content of heavy metals (Cu, Pb, Cd, Zn) in different fractions obtained after sequential extraction of soil from post-fire areas and from fire non disturbed areas were studied. In four plant species of Lamiaceae family (Ajuga genevensis L., Lamium galeobdolon (L.) L., Teucrium chamaedrys L., Acinos alpinus (L.) Moench.), that grow in typical habitats of the mountain, distribution of heavy metals in aerial parts and roots was investigated too. For all samples from post-fire area cation exchange capacity and soil organic matter content are increased while rH is decreased. Fire caused slightly increased bioavailability of the observed metals but more significant rise happened in metal amounts bound to oxides and organics. The plants showed variable behavior. T. chamaedrys collected on the post-fire area contained elevated concentrations of all analyzed metals. A. alpinus showed higher phytoaccumulation for Zn and Cd, while the other two plant species for Pb and Cd in the post-fire areas.

  19. Peptide-based, two-fluorophore, ratiometric probe for quantifying mobile zinc in biological solutions.

    Science.gov (United States)

    Zhang, Daniel Y; Azrad, Maria; Demark-Wahnefried, Wendy; Frederickson, Christopher J; Lippard, Stephen J; Radford, Robert J

    2015-02-20

    Small-molecule fluorescent sensors are versatile agents for detecting mobile zinc in biology. Capitalizing on the abundance of validated mobile zinc probes, we devised a strategy for repurposing existing intensity-based sensors for quantitative applications. Using solid-phase peptide synthesis, we conjugated a zinc-sensitive Zinpyr-1 derivative and a zinc-insensitive 7-hydroxycoumarin derivative onto opposite ends of a rigid P9K peptide scaffold to create HcZ9, a ratiometric fluorescent probe for mobile zinc. A plate reader-based assay using HcZ9 was developed, the accuracy of which is comparable to that of atomic absorption spectroscopy. We investigated zinc accumulation in prostatic cells and zinc levels in human seminal fluid. When normal and tumorigenic cells are bathed in zinc-enriched media, cellular mobile zinc is buffered and changes slightly, but total zinc levels increase significantly. Quantification of mobile and total zinc levels in human seminal plasma revealed that the two are positively correlated with a Pearson's coefficient of 0.73.

  20. [Zinc and type 2 diabetes].

    Science.gov (United States)

    Fukunaka, Ayako; Fujitani, Yoshio

    2016-07-01

    Pancreatic β cells contain the highest amount of zinc among cells within the human body, and hence, the relationship between zinc and diabetes has been a topic of great interest. While many studies demonstrating possible involvement of zinc deficiency in diabetes have been reported, precise mechanisms how zinc regulates glucose metabolism are still far from understood. Recent studies revealed that zinc can transmit signals that are driven by a variety of zinc transporters in a tissue and cell-type specific manner and deficiency in some zinc transporters may cause human diseases. Here, we review the role of zinc in metabolism particularly focusing on the emerging role of zinc transporters in diabetes.

  1. Protein kinase CK2 triggers cytosolic zinc signaling pathways by phosphorylation of zinc channel ZIP7.

    Science.gov (United States)

    Taylor, Kathryn M; Hiscox, Stephen; Nicholson, Robert I; Hogstrand, Christer; Kille, Peter

    2012-02-07

    The transition element zinc, which has recently been identified as an intracellular second messenger, has been implicated in various signaling pathways, including those leading to cell proliferation. Zinc channels of the ZIP (ZRT1- and IRT1-like protein) family [also known as solute carrier family 39A (SLC39A)] transiently increase the cytosolic free zinc (Zn(2+)) concentration in response to extracellular signals. We show that phosphorylation of evolutionarily conserved residues in endoplasmic reticulum zinc channel ZIP7 is associated with the gated release of Zn(2+) from intracellular stores, leading to activation of tyrosine kinases and the phosphorylation of AKT and extracellular signal-regulated kinases 1 and 2. Through pharmacological manipulation, proximity ligation assay, and mutagenesis, we identified protein kinase CK2 as the kinase responsible for ZIP7 activation. Together, the present results show that transition element channels in eukaryotes can be activated posttranslationally by phosphorylation, as part of a cell signaling cascade. Our study links the regulated release of zinc from intracellular stores to phosphorylation of kinases involved in proliferative responses and cell migration, suggesting a functional role for ZIP7 and zinc signals in these events. The connection with proliferation and migration, as well as the activation of ZIP7 by CK2, a kinase that is antiapoptotic and promotes cell division, suggests that ZIP7 may provide a target for anticancer drug development.

  2. Improved zinc electrode and rechargeable zinc-air battery

    Science.gov (United States)

    Ross, P.N. Jr.

    1988-06-21

    The invention comprises an improved rechargeable zinc-air cell/battery having recirculating alkaline electrolyte and a zinc electrode comprising a porous foam support material which carries the active zinc electrode material. 5 figs.

  3. Zinc finger structure-function in Ikaros

    Institute of Scientific and Technical Information of China (English)

    Marvin; A; Payne

    2011-01-01

    The zinc finger motif was used as a vehicle for the initial discovery of Ikaros in the context of T-cell differentiation and has been central to all subsequent analyses of Ikaros function.The Ikaros gene is alternately spliced to produce several isoforms that confer diversity of function and consequently have complicated analysis of the function of Ikaros in vivo.Key features of Ikaros in vivo function are associated with six C2H2 zinc fingers;four of which are alternately incorporated in the production of the various Ikaros isoforms.Although no complete structures are available for the Ikaros protein or any of its family members,considerable evidence has accumulated about the structure of zinc fingers and the role that this structure plays in the functions of the Ikaros family of proteins.This review summarizes the structural aspects of Ikaros zinc fingers,individually,and in tandem to provide a structural context for Ikaros function and to provide a structural basis to inform the design of future experiments with Ikaros and its family members.

  4. Chelators for investigating zinc metalloneurochemistry.

    Science.gov (United States)

    Radford, Robert J; Lippard, Stephen J

    2013-04-01

    The physiology and pathology of mobile zinc signaling has become an important topic in metalloneurochemistry. To study the action of mobile zinc effectively, specialized tools are required that probe the temporal and positional changes of zinc ions within live tissue and cells. In the present article we describe the design and implementation of selective zinc chelators as antagonists to interrogate the function of mobile zinc, with an emphasis on the pools of vesicular zinc in the terminals of hippocampal mossy fiber buttons.

  5. Parameters Influencing Zinc in Experimental Systems in Vivo and in Vitro

    Directory of Open Access Journals (Sweden)

    Johanna Ollig

    2016-03-01

    Full Text Available In recent years, the role of zinc in biological systems has been a subject of intense research. Despite wide increase in our knowledge and understanding of zinc homeostasis, numerous questions remain to be answered, encouraging further research. In particular, the quantification of intracellular zinc ions and fluctuation, as well as the function of zinc in signaling processes are being intensely investigated. The determination of free intracellular zinc ions is difficult and error-prone, as concentrations are extremely low (in the pico- to nanomolar range, but techniques exist involving fluorescent probes and sensors. In spite of zinc deficiency being accepted as a global problem, causing death and disease worldwide, to date there are no markers to reliably assess a person’s zinc status. This review summarizes the difficulties and major pitfalls when working with zinc in in vitro and in vivo research. Additionally, it specifies important aspects for zinc substitution and supplementation, including the bioavailability of zinc and its intestinal absorption. In particular, it is intended to help researchers with yet minor experience working with zinc efficiently set up experiments and avoid commonly occurring mistakes, starting with the choice and preparation of reagents and instrumentation, and concluding with possibilities for measuring the status of zinc in humans.

  6. Exploring zinc coordination in novel zinc battery electrolytes.

    Science.gov (United States)

    Kar, Mega; Winther-Jensen, Bjorn; Forsyth, Maria; MacFarlane, Douglas R

    2014-06-14

    The coordination of zinc ions by tetraglyme has been investigated here to support the development of novel electrolytes for rechargeable zinc batteries. Zn(2+) reduction is electrochemically reversible from tetraglyme. The spectroscopic data, molar conductivity and thermal behavior as a function of zinc composition, between mole ratios [80 : 20] and [50 : 50] [tetraglyme : zinc chloride], all suggest that strong interactions take place between chloro-zinc complexes and tetraglyme. Varying the concentration of zinc chloride produces a range of zinc-chloro species (ZnClx)(2-x) in solution, which hinder full interaction between the zinc ion and tetraglyme. Both the [70 : 30] and [50 : 50] mixtures are promising electrolyte candidates for reversible zinc batteries, such as the zinc-air device.

  7. Impedimetric detection of alcohol vapours using nanostructured zinc ferrite.

    Science.gov (United States)

    Kannan, Padmanathan Karthick; Saraswathi, Ramiah

    2014-11-01

    A comparative study on the sensing characteristics of nanostructured zinc ferrite to three primary alcohols viz. methanol, ethanol and propanol has been carried out. The zinc ferrite has been prepared by a combustion method and characterized by XRD, FTIR, AFM and SEM. Impedance studies in the alcohol concentration range varying from 100 to 1000 ppm show definite variations in response to both the nature of the alcohol and its concentration. The nanostructured zinc ferrite shows the highest sensor response to methanol and least to propanol. Equivalent circuit modelling and calibration have been made for all the three alcohol sensors. The material shows a better selectivity to the alcohols compared to formaldehyde, ammonia and acetone vapours.

  8. Highly Ordered Zinc Oxide Nanotubules Synthesized within the Anodic Aluminum Oxide Template

    Institute of Scientific and Technical Information of China (English)

    WANG Zhen; LI HuLin

    2001-01-01

    @@ Zinc oxide (ZnO) is a wide-band-gap semiconductor, which has a broad range of applications, e.g., in pigment, rubber additives, gas sensors, varistors and transducers1. It has recently been demonstrated that nanophase zinc oxide can be used in photocells of the Gatzel type2, which results in improved current generation efficiency. The properties of high aspect ratios and small sizes of zinc oxide nanotubules or nanowires are expected to improve the luminescence efficiency of the electro-optical devices and the sensitivity of the chemical sensors3.

  9. Highly Ordered Zinc Oxide Nanotubules Synthesized within the Anodic Aluminum Oxide Template

    Institute of Scientific and Technical Information of China (English)

    WANG; Zhen

    2001-01-01

    Zinc oxide (ZnO) is a wide-band-gap semiconductor, which has a broad range of applications, e.g., in pigment, rubber additives, gas sensors, varistors and transducers1. It has recently been demonstrated that nanophase zinc oxide can be used in photocells of the Gatzel type2, which results in improved current generation efficiency. The properties of high aspect ratios and small sizes of zinc oxide nanotubules or nanowires are expected to improve the luminescence efficiency of the electro-optical devices and the sensitivity of the chemical sensors3.  ……

  10. Zinc electrode and rechargeable zinc-air battery

    Science.gov (United States)

    Ross, Jr., Philip N.

    1989-01-01

    An improved zinc electrode is disclosed for a rechargeable zinc-air battery comprising an outer frame and a porous foam electrode support within the frame which is treated prior to the deposition of zinc thereon to inhibit the formation of zinc dendrites on the external surface thereof. The outer frame is provided with passageways for circulating an alkaline electrolyte through the treated zinc-coated porous foam. A novel rechargeable zinc-air battery system is also disclosed which utilizes the improved zinc electrode and further includes an alkaline electrolyte within said battery circulating through the passageways in the zinc electrode and an external electrolyte circulation means which has an electrolyte reservoir external to the battery case including filter means to filter solids out of the electrolyte as it circulates to the external reservoir and pump means for recirculating electrolyte from the external reservoir to the zinc electrode.

  11. Zinc in diet

    Science.gov (United States)

    ... Zinc is also needed for the senses of smell and taste. During pregnancy, infancy, and childhood the ... sense of taste Problems with the sense of smell Skin sores Slow growth Trouble seeing in the ...

  12. Zinc level and obesity

    Directory of Open Access Journals (Sweden)

    Doaa S.E. Zaky

    2013-01-01

    Conclusion Plasma zinc concentration in obese individuals showed an inverse relationship with the waist circumference and BMI as well as serum low-density lipoprotein-cholesterol and correlated positively with high-density lipoprotein.

  13. Zinc level and obesity

    OpenAIRE

    Doaa S.E Zaky; Eman A Sultan; Mahmoud F Salim; Rana S Dawod

    2013-01-01

    Background Obesity is a chronic condition that is associated with disturbances in the metabolism of zinc. Therefore, the aim of this study was to investigate the relationship between serum zinc level and different clinical and biochemical parameters in obese individuals. Patients and methods Twenty-four individuals with BMI more than 30 kg/m 2 and 14 healthy controls (BMI < 24 kg/m 2 ) were assessed for BMI and waist circumference using anthropometric measurements. Colorimetric tes...

  14. Chelating ionic liquids for reversible zinc electrochemistry.

    Science.gov (United States)

    Kar, Mega; Winther-Jensen, Bjorn; Forsyth, Maria; MacFarlane, Douglas R

    2013-05-21

    Advanced, high energy-density, metal-air rechargeable batteries, such as zinc-air, are of intense international interest due to their important role in energy storage applications such as electric and hybrid vehicles, and to their ability to deal with the intermittency of renewable energy sources such as solar and wind. Ionic liquids offer a number of ideal thermal and physical properties as potential electrolytes in such large-scale energy storage applications. We describe here the synthesis and characterisation of a family of novel "chelating" ILs designed to chelate and solubilize the zinc ions to create electrolytes for this type of battery. These are based on quaternary alkoxy alkyl ammonium cations of varying oligo-ether side chains and anions such as p-toluene sulfonate, bis(trifluoromethylsulfonyl)amide and dicyanoamides. This work shows that increasing the ether chain length in the cation from two to four oxygens can increase the ionic conductivity and reduce the melting point from 67 °C to 15 °C for the tosylate system. Changing the anion also plays a significant role in the nature of the zinc deposition electrochemistry. We show that zinc can be reversibly deposited from [N(222(20201))][NTf2] and [N(222(202020201))][NTf2] beginning at -1.4 V and -1.7 V vs. SHE, respectively, but not in the case of tosylate based ILs. This indicates that the [NTf2] is a weaker coordinating anion with the zinc cation, compared to the tosylate anion, allowing the coordination of the ether chain to dominate the behavior of the deposition and stripping of zinc ions.

  15. The bioavailability of four zinc oxide sources and zinc sulphate in broiler chickens

    OpenAIRE

    Veldkamp, T.; Diepen, van, C.A.; Bikker, P.

    2014-01-01

    Zinc is an essential trace element for all farm animal species. It is commonly included in animal diets as zinc oxide, zinc sulphate or organically bound zinc. Umicore Zinc Chemicals developed zinc oxide products with different mean particle sizes. Umicore Zinc Chemicals requested Wageningen UR Livestock Research to determine the bioavailability of four zinc oxide sources and zinc sulphate in broiler chickens. A precise estimate of the bioavailability of zinc sources is required both for fulf...

  16. Treatment of zinc deficiency without zinc fortification

    Institute of Scientific and Technical Information of China (English)

    Donald OBERLEAS; Barbara F. HARLAND

    2008-01-01

    Zinc (Zn) deficiency in animals became of interest until the 1950s. In this paper, progresses in researches on physi-ology of Zn deficiency in animals, phytate effect on bioavailability of Zn, and role of phytase in healing Zn deficiency of animals were reviewed. Several studies demonstrated that Zn is recycled via the pancreas; the problem of Zn deficiency was controlled by Zn homeostasis. The endogenous secretion of Zn is considered as an important factor influencing Zn deficiency, and the critical molar ratio is 10. Phytate (inositol hexaphosphate) constituted up to 90% of the organically bound phosphorus in seeds. Great improvement has been made in recent years on isolating and measuring phytate, and its structure is clear. Phytate is considered to reduce Zn bioavailability in animal. Phytase is the enzyme that hydrolyzes phytate and is present in yeast, rye bran, wheat bran, barley, triticale, and many bacteria and fungi. Zinc nutrition and bioavailability can be enhanced by addition of phytase to animal feeds. Therefore, using phytase as supplements, the most prevalent Zn deficiency in animals may be effectively corrected without the mining and smelting of several tons of zinc daily needed to correct this deficiency by fortification worldwide.

  17. Trace elements in human physiology and pathology: zinc and metallothioneins.

    Science.gov (United States)

    Tapiero, Haim; Tew, Kenneth D

    2003-11-01

    Zinc is one of the most abundant nutritionally essential elements in the human body. It is found in all body tissues with 85% of the whole body zinc in muscle and bone, 11% in the skin and the liver and the remaining in all the other tissues. In multicellular organisms, virtually all zinc is intracellular, 30-40% is located in the nucleus, 50% in the cytoplasm, organelles and specialized vesicles (for digestive enzymes or hormone storage) and the remainder in the cell membrane. Zinc intake ranges from 107 to 231 micromol/d depending on the source, and human zinc requirement is estimated at 15 mg/d. Zinc has been shown to be essential to the structure and function of a large number of macromolecules and for over 300 enzymic reactions. It has both catalytic and structural roles in enzymes, while in zinc finger motifs, it provides a scaffold that organizes protein sub-domains for the interaction with either DNA or other proteins. It is critical for the function of a number of metalloproteins, inducing members of oxido-reductase, hydrolase ligase, lyase family and has co-activating functions with copper in superoxide dismutase or phospholipase C. The zinc ion (Zn(++)) does not participate in redox reactions, which makes it a stable ion in a biological medium whose potential is in constant flux. Zinc ions are hydrophilic and do not cross cell membranes by passive diffusion. In general, transport has been described as having both saturable and non-saturable components, depending on the Zn(II) concentrations involved. Zinc ions exist primarily in the form of complexes with proteins and nucleic acids and participate in all aspects of intermediary metabolism, transmission and regulation of the expression of genetic information, storage, synthesis and action of peptide hormones and structural maintenance of chromatin and biomembranes.

  18. Zinc fate in animal husbandry systems.

    Science.gov (United States)

    Romeo, A; Vacchina, V; Legros, S; Doelsch, E

    2014-11-01

    Zinc (Zn) is considered in animal production systems as both an essential nutrient and a possible pollutant. While it is generally supplemented at low levels in animal diets, with less than 200 mg kg(-1) in complete feeds, it is under scrutiny due to potential accumulation in the environment. This explains why international regulations limit maximum supplementation levels in animal feeds in a stricter way. This article gives an overview of the current knowledge on the fate of zinc in animal production systems, from animal diets to animal wastes. Some analytical methods can be used for the quantification and qualification of Zn chemical forms: X-ray crystallography, electrospray tandem mass spectrometry, separation techniques, hyphenated techniques… Analysis of chelated forms issued from complex matrices, like hydrolysed proteins, remains difficult, and the speciation of Zn in diluted carriers (premix and feed) is a challenge. Our understanding of Zn absorption has made progress with recent research on ZnT/Zip families and metallothioneins. However, fine-tuned approaches towards the nutritional and metabolic interactions for Zn supplementation in farm conditions still require further studies. The speciation of zinc in pig manure and poultry litter has been a priority as monogastric animals are usually raised under intensive conditions and fed with high quantities of trace minerals, leading to high animal density and elevated quantities of zinc from animal wastes.

  19. LiZIP3 is a cellular zinc transporter that mediates the tightly regulated import of zinc in Leishmania infantum parasites

    Science.gov (United States)

    Carvalho, Sandra; da Silva, Rosa Barreira; Shawki, Ali; Castro, Helena; Lamy, Márcia; Eide, David; Costa, Vítor; Mackenzie, Bryan; Tomás, Ana M.

    2016-01-01

    Summary Cellular zinc homeostasis ensures that the intracellular concentration of this element is kept within limits that enable its participation in critical physiological processes without exerting toxic effects. We report here the identification and characterization of the first mediator of zinc homeostasis in Leishmania infantum, LiZIP3, a member of the ZIP family of divalent metal-ion transporters. The zinc transporter activity of LiZIP3 was first disclosed by its capacity to rescue the growth of Saccharomyces cerevisiae strains deficient in zinc acquisition. Subsequent expression of LiZIP3 in Xenopus laevis oocytes was shown to stimulate the uptake of a broad range of metal ions, among which Zn2+ was the preferred LiZIP3 substrate (K0.5 ≈ 0.1 μM). Evidence that LiZIP3 functions as a zinc importer in L. infantum came from the observations that the protein locates to the cell membrane and that its overexpression leads to augmented zinc internalization. Importantly, expression and cell-surface location of LiZIP3 are lost when parasites face high zinc bioavailability. LiZIP3 decline in response to zinc is regulated at the mRNA level in a process involving (a) short-lived protein(s). Collectively, our data reveal that LiZIP3 enables L. infantum to acquire zinc in a highly regulated manner, hence contributing to zinc homeostasis. PMID:25644708

  20. Gender dependent evaluation of autism like behavior in mice exposed to prenatal zinc deficiency

    Directory of Open Access Journals (Sweden)

    Stefanie eGrabrucker

    2016-03-01

    Full Text Available Zinc deficiency has recently been linked to the etiology of autism spectrum disorders (ASD as environmental risk factor. With an estimated 17% of the world population being at risk of zinc deficiency, especially zinc deficiency during pregnancy might be a common occurrence, also in industrialized nations. On molecular level, zinc deficiency has been shown to affect a signaling pathway at glutamatergic synapses that has previously been identified through genetic mutations in ASD patients, the Neurexin-Neuroligin-Shank pathway, via altering zinc binding Shank family members. In particular, prenatal zinc deficient but not acute zinc deficient animals have been reported to display autism like behavior in some behavioral tests. However, a full behavioral analysis of a possible autism like behavior has been lacking so far. Here, we performed an extensive behavioral phenotyping of mice born from mothers with mild zinc deficiency during all trimesters of pregnancy. Prenatal zinc deficient animals were investigated as adults and gender differences were assessed. Our results show that prenatal zinc deficient mice display increased anxiety, deficits in nest building and various social interaction paradigm, as well as mild alterations in ultrasonic vocalizations. A gender specific analysis revealed only few sex specific differences. Taken together, given that similar behavioral abnormalities as reported here are frequently observed in ASD mouse models, we conclude that prenatal zinc deficient animals even without specific genetic susceptibility for ASD, already show some features of ASD like behavior.

  1. Zinc and its transporters, pancreatic β-cells, and insulin metabolism.

    Science.gov (United States)

    Huang, Liping

    2014-01-01

    Zinc is an essential trace metal for life. Two families of zinc transporters, SLC30A (ZNT) and SLC39A (ZIP) are required for maintaining cellular zinc homeostasis. ZNTs function to decrease cytoplasmic zinc concentrations whereas ZIPs do the opposite. Expression of zinc transporters can be tissue/cell-type specific or ubiquitous. Zinc transporters that are limited in tissue/cell distributions usually perform specialized tasks to satisfy biological processes in a given cell. For example, ZNT8 is mainly expressed in β-cells and functions to deliver zinc into granules for insulin maturation and secretion. Many other zinc transporters are also expressed in β-cells. Defects in these zinc transporters have been associated with abnormalities in insulin synthesis, maturation, and secretion and subsequent glucose metabolism. This review focuses on the specific roles of zinc and its transporters in insulin metabolism and describes the current knowledge of the function of zinc transporters in β-cell health in animal knockout mouse models with respect to diabetes development in humans.

  2. Gender Dependent Evaluation of Autism like Behavior in Mice Exposed to Prenatal Zinc Deficiency.

    Science.gov (United States)

    Grabrucker, Stefanie; Boeckers, Tobias M; Grabrucker, Andreas M

    2016-01-01

    Zinc deficiency has recently been linked to the etiology of autism spectrum disorders (ASD) as environmental risk factor. With an estimated 17% of the world population being at risk of zinc deficiency, especially zinc deficiency during pregnancy might be a common occurrence, also in industrialized nations. On molecular level, zinc deficiency has been shown to affect a signaling pathway at glutamatergic synapses that has previously been identified through genetic mutations in ASD patients, the Neurexin-Neuroligin-Shank pathway, via altering zinc binding Shank family members. In particular, prenatal zinc deficient but not acute zinc deficient animals have been reported to display autism like behavior in some behavioral tests. However, a full behavioral analysis of a possible autism like behavior has been lacking so far. Here, we performed an extensive behavioral phenotyping of mice born from mothers with mild zinc deficiency during all trimesters of pregnancy. Prenatal zinc deficient animals were investigated as adults and gender differences were assessed. Our results show that prenatal zinc deficient mice display increased anxiety, deficits in nest building and various social interaction paradigm, as well as mild alterations in ultrasonic vocalizations. A gender specific analysis revealed only few sex specific differences. Taken together, given that similar behavioral abnormalities as reported here are frequently observed in ASD mouse models, we conclude that prenatal zinc deficient animals even without specific genetic susceptibility for ASD, already show some features of ASD like behavior.

  3. The five AhMTP1 zinc transporters undergo different evolutionary fates towards adaptive evolution to zinc tolerance in Arabidopsis halleri.

    Science.gov (United States)

    Shahzad, Zaigham; Gosti, Françoise; Frérot, Hélène; Lacombe, Eric; Roosens, Nancy; Saumitou-Laprade, Pierre; Berthomieu, Pierre

    2010-04-15

    Gene duplication is a major mechanism facilitating adaptation to changing environments. From recent genomic analyses, the acquisition of zinc hypertolerance and hyperaccumulation characters discriminating Arabidopsis halleri from its zinc sensitive/non-accumulator closest relatives Arabidopsis lyrata and Arabidopsis thaliana was proposed to rely on duplication of genes controlling zinc transport or zinc tolerance. Metal Tolerance Protein 1 (MTP1) is one of these genes. It encodes a Zn(2+)/H(+) antiporter involved in cytoplasmic zinc detoxification and thus in zinc tolerance. MTP1 was proposed to be triplicated in A. halleri, while it is present in single copy in A. thaliana and A. lyrata. Two of the three AhMTP1 paralogues were shown to co-segregate with zinc tolerance in a BC1 progeny from a cross between A. halleri and A. lyrata. In this work, the MTP1 family was characterized at both the genomic and functional levels in A. halleri. Five MTP1 paralogues were found to be present in A. halleri, AhMTP1-A1, -A2, -B, -C, and -D. Interestingly, one of the two newly identified AhMTP1 paralogues was not fixed at least in one A. halleri population. All MTP1s were expressed, but transcript accumulation of the paralogues co-segregating with zinc tolerance in the A. halleri X A. lyrata BC1 progeny was markedly higher than that of the other paralogues. All MTP1s displayed the ability to functionally complement a Saccharomyces cerevisiae zinc hypersensitive mutant. However, the paralogue showing the least complementation of the yeast mutant phenotype was one of the paralogues co-segregating with zinc tolerance. From our results, the hypothesis that pentaplication of MTP1 could be a major basis of the zinc tolerance character in A. halleri is strongly counter-balanced by the fact that members of the MTP1 family are likely to experience different evolutionary fates, some of which not concurring to increase zinc tolerance.

  4. The kinetic of photoreactions in zinc oxide microrods

    Science.gov (United States)

    Fiedot, M.; Rac, O.; Suchorska-Woźniak, P.; Nawrot, W.; Teterycz, H.

    2016-01-01

    Zinc oxide is the oldest sensing material used in the chemical resistive gas sensors which allow to detect many gases, such as carbon oxide, nitrogen oxides and other. This material is also widely used in medicine and daily life as antibacterial agent. For this reason this semiconductor is often synthesized on the polymer substrates such as foils and textiles. In presented results zinc oxide was deposited on the surface of poly(ethylene terephthalate) foil to obtain antibacterial material. As synthesis method chemical bath deposition was chosen. The growth of zinc oxide structures was carried out in water solution of zinc nitrate (V) and hexamethylenetetramine in 90°C during 9 h. Because antibacterial properties of ZnO are strongly depended on photocatalytic and electric properties of this semiconductor impedance spectroscopy measurements were carried out. During the measurements material was tested with and without UV light to determinate the kinetic of photoreactions in zinc oxide. Moreover the composite was analyzed by XRD diffraction and scanning electron microscope. The X-ray analysis indicated that obtained material has the structure of wurtzite which is typical of zinc oxide. SEM images showed that on the PET foil microrods of ZnO were formed. The impedance spectroscopy measurements of ZnO layer showed that in UV light significant changes in the conductivity of the material are observed.

  5. A high amount of dietary zinc changes the expression of zinc transporters and metallothionein in jejunal epithelial cells in vitro and in vivo but does not prevent zinc accumulation in jejunal tissue of piglets.

    Science.gov (United States)

    Martin, Lena; Lodemann, Ulrike; Bondzio, Angelika; Gefeller, Eva-Maria; Vahjen, Wilfried; Aschenbach, Jörg Rudolf; Zentek, Jürgen; Pieper, Robert

    2013-08-01

    High dietary zinc concentrations are used to prevent or treat diarrhea in piglets and humans, but long-term adaptation to high zinc supply has yet not been assessed. Intestinal zinc uptake is facilitated through members of zinc transporter families SLC30 (ZnT) and SLC39 (ZIP). Whereas in rodents, regulation of zinc homeostasis at low or adequate zinc supply has been described, such mechanisms are unclear in piglets. A total of 54 piglets were fed diets containing 57 [low dietary zinc (LZn)], 164 [normal dietary zinc (NZn)], or 2425 [high dietary zinc (HZn)] mg/kg dry matter zinc. After 4 wk, 10 piglets/group were killed and jejunal tissues taken for analysis of zinc transporters SLC30A1 (ZnT1), SLC30A2 (ZnT2), SLC30A5 (ZnT5), SLC39A4 (ZIP4), divalent metal transporter 1 (DMT1), and metallothionein-1 (MT). Weight gain was higher (P < 0.05) in pigs fed HZn than in the LZn and NZn groups during the first 2 wk. Food intake did not differ between groups. The digesta and jejunal tissue zinc concentrations were higher (P < 0.05) in the HZn pigs than in NZn and LZn pigs. Expression of ZnT1 was higher (P < 0.05) and ZIP4 lower (P < 0.05) in HZn pigs than in the 2 other groups, whereas expression of ZnT5 and DMT1 did not differ between treatments. Expression of ZnT2 was lower (P < 0.05) in the LZn group than in the HZn and NZn groups. The mRNA expression and protein abundance of MT was higher (P < 0.05) in the HZn group than in the NZn and LZn groups. Studies with intestinal porcine cell line intestinal epithelial cell-J2 confirmed the dose-dependent downregulation of ZIP4 and upregulation of ZnT1 and MT (P < 0.05) with increasing zinc concentration within 24 h. In conclusion, high dietary zinc concentrations increase intracellular zinc, promote increased zinc export from intestinal tissues into extracellular compartments, and decrease zinc uptake from the gut lumen. The adaptive process appears to be established within 24 h; however, it does not prevent tissue zinc

  6. Zinc Determination in Pleural Fluid

    OpenAIRE

    Nazan DEMİR; DEMİR, Yaşar

    2000-01-01

    In this study, an enzymatic zinc determination method was applied to pleural fluid, the basis of which was the regaining of the activity of apo carbonic anhydrase by the zinc present in the sample. The method was used for pleural fluid zinc determination in order to show the application to body fluids other than serum. For this purpose, pleural fluids were obtained from 20 patients and zinc concentrations were determined. Carbonic anhydrase was purified by affinity chromatography from bovine ...

  7. The bioavailability of four zinc oxide sources and zinc sulphate in broiler chickens

    NARCIS (Netherlands)

    Veldkamp, T.; Diepen, van J.T.M.; Bikker, P.

    2014-01-01

    Zinc is an essential trace element for all farm animal species. It is commonly included in animal diets as zinc oxide, zinc sulphate or organically bound zinc. Umicore Zinc Chemicals developed zinc oxide products with different mean particle sizes. Umicore Zinc Chemicals requested Wageningen UR

  8. The bioavailability of four zinc oxide sources and zinc sulphate in broiler chickens

    NARCIS (Netherlands)

    Veldkamp, T.; Diepen, van J.T.M.; Bikker, P.

    2014-01-01

    Zinc is an essential trace element for all farm animal species. It is commonly included in animal diets as zinc oxide, zinc sulphate or organically bound zinc. Umicore Zinc Chemicals developed zinc oxide products with different mean particle sizes. Umicore Zinc Chemicals requested Wageningen UR Live

  9. Environmental risk limits for zinc

    NARCIS (Netherlands)

    Bodar CWM; SEC

    2007-01-01

    Environmental Riks Limits (ERLs) were derived for zinc. ERLs serve as advisory values to set environmental quality standards in the Netherlands. The ERLs for zinc closely follow the outcomes of earlier discussions on zinc within the Water Framework Directive and EC Regulation 793/93. The ERLs refer

  10. Environmental risk limits for zinc

    NARCIS (Netherlands)

    Bodar CWM; SEC

    2007-01-01

    Environmental Riks Limits (ERLs) were derived for zinc. ERLs serve as advisory values to set environmental quality standards in the Netherlands. The ERLs for zinc closely follow the outcomes of earlier discussions on zinc within the Water Framework Directive and EC Regulation 793/93. The ERLs ref

  11. Zinc Phosphide Poisoning

    Directory of Open Access Journals (Sweden)

    Erdal Doğan

    2014-01-01

    Full Text Available Zinc phosphide has been used widely as a rodenticide. Upon ingestion, it gets converted to phosphine gas in the body, which is subsequently absorbed into the bloodstream through the stomach and the intestines and gets captured by the liver and the lungs. Phosphine gas produces various metabolic and nonmetabolic toxic effects. Clinical symptoms are circulatory collapse, hypotension, shock symptoms, myocarditis, pericarditis, acute pulmonary edema, and congestive heart failure. In this case presentation, we aim to present the intensive care process and treatment resistance of a patient who ingested zinc phosphide for suicide purposes.

  12. A role for dZIP89B in Drosophila dietary zinc uptake reveals additional complexity in the zinc absorption process.

    Science.gov (United States)

    Richards, Christopher D; Warr, Coral G; Burke, Richard

    2015-12-01

    Dietary zinc is the principal source of zinc in eukaryotes, with its uptake and distribution controlled by a complex network of numerous membrane-spanning transport proteins. Dietary absorption is achieved by members of the SLC39A (ZIP) gene family, which encode proteins that are generally responsible for the movement of zinc into the cytosol. ZIP4 is thought to be the primary mammalian zinc uptake gene in the small intestine, with mutations in this gene causing the zinc deficiency disease Acrodermatitis enteropathica. In Drosophila, dual knockdown of the major dietary zinc uptake genes dZIP42C.1 (dZIP1) and dZIP42C.2 (dZIP2) results in a severe sensitivity to zinc-deficient media. However, the symptoms associated with ZIP4 loss can be reversed by zinc supplementation and dZIP42C.1 and 2 knockdown has minimal effect under normal dietary conditions, suggesting that additional pathways for zinc absorption exist in both mammals and flies. This study provides evidence that dZIP89B is an ideal candidate for this role in Drosophila, encoding a low-affinity zinc uptake transporter active in the posterior midgut. Flies lacking dZIP89B, while viable and apparently healthy, show indications of low midgut zinc levels, including reduced metallothionein B expression and compensatory up-regulation of dZIP42C.1 and 2. Furthermore dZIP89B mutants display a dramatic resistance to toxic dietary zinc levels which is abrogated by midgut-specific restoration of dZIP89B activity. We postulate that dZIP89B works in concert with the closely related dZIP42C.1 and 2 to ensure optimal zinc absorption under a range of dietary conditions.

  13. Conservation, diversification and expansion of C2H2 zinc finger proteins in the Arabidopsis thaliana genome

    Directory of Open Access Journals (Sweden)

    Böhm Siegfried

    2004-07-01

    Full Text Available Background The classical C2H2 zinc finger domain is involved in a wide range of functions and can bind to DNA, RNA and proteins. The comparison of zinc finger proteins in several eukaryotes has shown that there is a lot of lineage specific diversification and expansion. Although the number of characterized plant proteins that carry the classical C2H2 zinc finger motifs is growing, a systematic classification and analysis of a plant genome zinc finger gene set is lacking. Results We found through in silico analysis 176 zinc finger proteins in Arabidopsis thaliana that hence constitute the most abundant family of putative transcriptional regulators in this plant. Only a minority of 33 A. thaliana zinc finger proteins are conserved in other eukaryotes. In contrast, the majority of these proteins (81% are plant specific. They are derived from extensive duplication events and form expanded families. We assigned the proteins to different subgroups and families and focused specifically on the two largest and evolutionarily youngest families (A1 and C1 that are suggested to be primarily involved in transcriptional regulation. The newly defined family A1 (24 members comprises proteins with tandemly arranged zinc finger domains. Family C1 (64 members, earlier described as the EPF-family in Petunia, comprises proteins with one isolated or two to five dispersed fingers and a mostly invariant QALGGH motif in the zinc finger helices. Based on the amino acid pattern in these helices we could describe five different signature sequences prevalent in C1 zinc finger domains. We also found a number of non-finger domains that are conserved in these families. Conclusions Our analysis of the few evolutionarily conserved zinc finger proteins of A. thaliana suggests that most of them could be involved in ancient biological processes like RNA metabolism and chromatin-remodeling. In contrast, the majority of the unique A. thaliana zinc finger proteins are known or

  14. Fishy business: effect of omega-3 fatty acids on zinc transporters and free zinc availability in human neuronal cells.

    Science.gov (United States)

    De Mel, Damitha; Suphioglu, Cenk

    2014-08-15

    Omega-3 (ω-3) fatty acids are one of the two main families of long chain polyunsaturated fatty acids (PUFA). The main omega-3 fatty acids in the mammalian body are α-linolenic acid (ALA), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Central nervous tissues of vertebrates are characterized by a high concentration of omega-3 fatty acids. Moreover, in the human brain, DHA is considered as the main structural omega-3 fatty acid, which comprises about 40% of the PUFAs in total. DHA deficiency may be the cause of many disorders such as depression, inability to concentrate, excessive mood swings, anxiety, cardiovascular disease, type 2 diabetes, dry skin and so on. On the other hand, zinc is the most abundant trace metal in the human brain. There are many scientific studies linking zinc, especially excess amounts of free zinc, to cellular death. Neurodegenerative diseases, such as Alzheimer's disease, are characterized by altered zinc metabolism. Both animal model studies and human cell culture studies have shown a possible link between omega-3 fatty acids, zinc transporter levels and free zinc availability at cellular levels. Many other studies have also suggested a possible omega-3 and zinc effect on neurodegeneration and cellular death. Therefore, in this review, we will examine the effect of omega-3 fatty acids on zinc transporters and the importance of free zinc for human neuronal cells. Moreover, we will evaluate the collective understanding of mechanism(s) for the interaction of these elements in neuronal research and their significance for the diagnosis and treatment of neurodegeneration.

  15. Fishy Business: Effect of Omega-3 Fatty Acids on Zinc Transporters and Free Zinc Availability in Human Neuronal Cells

    Directory of Open Access Journals (Sweden)

    Damitha De Mel

    2014-08-01

    Full Text Available Omega-3 (ω-3 fatty acids are one of the two main families of long chain polyunsaturated fatty acids (PUFA. The main omega-3 fatty acids in the mammalian body are α-linolenic acid (ALA, docosahexaenoic acid (DHA and eicosapentaenoic acid (EPA. Central nervous tissues of vertebrates are characterized by a high concentration of omega-3 fatty acids. Moreover, in the human brain, DHA is considered as the main structural omega-3 fatty acid, which comprises about 40% of the PUFAs in total. DHA deficiency may be the cause of many disorders such as depression, inability to concentrate, excessive mood swings, anxiety, cardiovascular disease, type 2 diabetes, dry skin and so on. On the other hand, zinc is the most abundant trace metal in the human brain. There are many scientific studies linking zinc, especially excess amounts of free zinc, to cellular death. Neurodegenerative diseases, such as Alzheimer’s disease, are characterized by altered zinc metabolism. Both animal model studies and human cell culture studies have shown a possible link between omega-3 fatty acids, zinc transporter levels and free zinc availability at cellular levels. Many other studies have also suggested a possible omega-3 and zinc effect on neurodegeneration and cellular death. Therefore, in this review, we will examine the effect of omega-3 fatty acids on zinc transporters and the importance of free zinc for human neuronal cells. Moreover, we will evaluate the collective understanding of mechanism(s for the interaction of these elements in neuronal research and their significance for the diagnosis and treatment of neurodegeneration.

  16. Doped zinc oxide microspheres

    Science.gov (United States)

    Arnold, Jr., Wesley D.; Bond, Walter D.; Lauf, Robert J.

    1993-01-01

    A new composition and method of making same for a doped zinc oxide microsphere and articles made therefrom for use in an electrical surge arrestor which has increased solid content, uniform grain size and is in the form of a gel.

  17. Zinc in multiple sclerosis

    DEFF Research Database (Denmark)

    Bredholt, Mikkel; Fredriksen, Jette Lautrup

    2016-01-01

    In the last 35 years, zinc (Zn) has been examined for its potential role in the disease multiple sclerosis (MS). This review gives an overview of the possible role of Zn in the pathogenesis of MS as well as a meta-analysis of studies having measured Zn in serum or plasma in patients with MS...

  18. Creep Resistant Zinc Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Frank E. Goodwin

    2002-12-31

    This report covers the development of Hot Chamber Die Castable Zinc Alloys with High Creep Strengths. This project commenced in 2000, with the primary objective of developing a hot chamber zinc die-casting alloy, capable of satisfactory service at 140 C. The core objectives of the development program were to: (1) fill in missing alloy data areas and develop a more complete empirical model of the influence of alloy composition on creep strength and other selected properties, and (2) based on the results from this model, examine promising alloy composition areas, for further development and for meeting the property combination targets, with the view to designing an optimized alloy composition. The target properties identified by ILZRO for an improved creep resistant zinc die-casting alloy were identified as follows: (1) temperature capability of 1470 C; (2) creep stress of 31 MPa (4500 psi); (3) exposure time of 1000 hours; and (4) maximum creep elongation under these conditions of 1%. The project was broadly divided into three tasks: (1) Task 1--General and Modeling, covering Experimental design of a first batch of alloys, alloy preparation and characterization. (2) Task 2--Refinement and Optimization, covering Experimental design of a second batch of alloys. (3) Task 3--Creep Testing and Technology transfer, covering the finalization of testing and the transfer of technology to the Zinc industry should have at least one improved alloy result from this work.

  19. Creep Resistant Zinc Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Frank E. Goodwin

    2002-12-31

    This report covers the development of Hot Chamber Die Castable Zinc Alloys with High Creep Strengths. This project commenced in 2000, with the primary objective of developing a hot chamber zinc die-casting alloy, capable of satisfactory service at 140 C. The core objectives of the development program were to: (1) fill in missing alloy data areas and develop a more complete empirical model of the influence of alloy composition on creep strength and other selected properties, and (2) based on the results from this model, examine promising alloy composition areas, for further development and for meeting the property combination targets, with the view to designing an optimized alloy composition. The target properties identified by ILZRO for an improved creep resistant zinc die-casting alloy were identified as follows: (1) temperature capability of 1470 C; (2) creep stress of 31 MPa (4500 psi); (3) exposure time of 1000 hours; and (4) maximum creep elongation under these conditions of 1%. The project was broadly divided into three tasks: (1) Task 1--General and Modeling, covering Experimental design of a first batch of alloys, alloy preparation and characterization. (2) Task 2--Refinement and Optimization, covering Experimental design of a second batch of alloys. (3) Task 3--Creep Testing and Technology transfer, covering the finalization of testing and the transfer of technology to the Zinc industry should have at least one improved alloy result from this work.

  20. Zinc in Multiple Sclerosis

    DEFF Research Database (Denmark)

    Bredholt, Mikkel; Frederiksen, Jette Lautrup

    2016-01-01

    In the last 35 years, zinc (Zn) has been examined for its potential role in the disease multiple sclerosis (MS). This review gives an overview of the possible role of Zn in the pathogenesis of MS as well as a meta-analysis of studies having measured Zn in serum or plasma in patients with MS...

  1. Zinc Oxide Nanoparticles for Revolutionizing Agriculture: Synthesis and Applications

    Directory of Open Access Journals (Sweden)

    Sidra Sabir

    2014-01-01

    Full Text Available Nanotechnology is the most innovative field of 21st century. Extensive research is going on for commercializing nanoproducts throughout the world. Due to their unique properties, nanoparticles have gained considerable importance compared to bulk counterparts. Among other metal nanoparticles, zinc oxide nanoparticles are very much important due to their utilization in gas sensors, biosensors, cosmetics, drug-delivery systems, and so forth. Zinc oxide nanoparticles (ZnO NPs also have remarkable optical, physical, and antimicrobial properties and therefore have great potential to enhance agriculture. As far as method of formation is concerned, ZnO NPs can be synthesized by several chemical methods such as precipitation method, vapor transport method, and hydrothermal process. The biogenic synthesis of ZnO NPs by using different plant extracts is also common nowadays. This green synthesis is quite safe and ecofriendly compared to chemical synthesis. This paper elaborates the synthesis, properties, and applications of zinc oxide nanoparticles.

  2. Nanostructured zinc oxide thin film by simple vapor transport deposition

    Science.gov (United States)

    Athma, P. V.; Martinez, Arturo I.; Johns, N.; Safeera, T. A.; Reshmi, R.; Anila, E. I.

    2015-09-01

    Zinc oxide (ZnO) nanostructures find applications in optoelectronic devices, photo voltaic displays and sensors. In this work zinc oxide nanostructures in different forms like nanorods, tripods and tetrapods have been synthesized by thermal evaporation of zinc metal and subsequent deposition on a glass substrate by vapor transport in the presence of oxygen. It is a comparatively simpler and environment friendly technique for the preparation of thin films. The structure, morphology and optical properties of the synthesized nanostructured thin film were characterized in detail by using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and photoluminescence (PL). The film exhibited bluish white emission with Commission International d'Eclairage (CIE) coordinates x = 0.22, y = 0.31.

  3. Studies on nanocrystalline zinc coating

    Indian Academy of Sciences (India)

    H B Muralidhara; Y Arthoba Naik

    2008-08-01

    Nano zinc coatings were deposited on mild steel by electrodeposition. The effect of additive on the morphology of crystal size on zinc deposit surface and corrosion properties were investigated. Corrosion tests were performed for dull zinc deposits and bright zinc deposits in aqueous NaCl solution (3.5 wt.%) using electrochemical measurements. The results showed that addition of additive in the deposition process of zinc significantly increased the corrosion resistance. The surface morphology of the zinc deposits was studied by scanning electron microscopy (SEM). The preferred orientation and average size of the zinc electrodeposited particles were obtained by X-ray diffraction analysis. The particles size was also characterized by TEM analysis.

  4. Ambient Sensors

    NARCIS (Netherlands)

    Börner, Dirk; Specht, Marcus

    2014-01-01

    This software sketches comprise two custom-built ambient sensors, i.e. a noise and a movement sensor. Both sensors measure an ambient value and process the values to a color gradient (green > yellow > red). The sensors were built using the Processing 1.5.1 development environment. Available under th

  5. Ambient Sensors

    NARCIS (Netherlands)

    Börner, Dirk; Specht, Marcus

    2014-01-01

    This software sketches comprise two custom-built ambient sensors, i.e. a noise and a movement sensor. Both sensors measure an ambient value and process the values to a color gradient (green > yellow > red). The sensors were built using the Processing 1.5.1 development environment. Available under

  6. The Application of Nafion Metal Catalyst Free Carbon Nanotube Modified Gold Electrode: Voltammetric Zinc Detection in Serum

    Science.gov (United States)

    Yue, Wei; Bange, Adam; Riehl, Bill L.; Johnson, Jay M.; Papautsky, Ian; Heineman, William R.

    2013-01-01

    Metal catalyst free carbon nanotube (MCFCNT) whiskers were first used as an electrode modification material on a gold electrode surface for zinc voltammetric measurements. A composite film of Nafion and MCFCNT whiskers was applied to a gold electrode surface to form a mechanically stable sensor. The sensor was then used for zinc detection in both acetate buffer solution and extracted bovine serum solution. A limit of detection of 53 nM was achieved for a 120 s deposition time. The zinc in bovine serum was extracted via a double extraction procedure using dithizone in chloroform as a zinc chelating ligand. The modified electrode was found to be both reliable and sensitive for zinc measurements in both matrices. PMID:24436574

  7. A Zinc Oxide Nanorod Ammonia Microsensor Integrated with a Readout Circuit on-a-Chip

    Directory of Open Access Journals (Sweden)

    Chyan-Chyi Wu

    2011-11-01

    Full Text Available A zinc oxide nanorod ammonia microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.35 mm complementary metal oxide semiconductor (CMOS process was investigated. The structure of the ammonia sensor is composed of a sensitive film and polysilicon electrodes. The ammonia sensor requires a post-process to etch the sacrificial layer, and to coat the sensitive film on the polysilicon electrodes. The sensitive film that is prepared by a hydrothermal method is made of zinc oxide. The sensor resistance changes when the sensitive film adsorbs or desorbs ammonia gas. The readout circuit is used to convert the sensor resistance into the voltage output. Experiments show that the ammonia sensor has a sensitivity of about 1.5 mV/ppm at room temperature.

  8. A zinc oxide nanorod ammonia microsensor integrated with a readout circuit on-a-chip.

    Science.gov (United States)

    Yang, Ming-Zhi; Dai, Ching-Liang; Wu, Chyan-Chyi

    2011-01-01

    A zinc oxide nanorod ammonia microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.35 μm complementary metal oxide semiconductor (CMOS) process was investigated. The structure of the ammonia sensor is composed of a sensitive film and polysilicon electrodes. The ammonia sensor requires a post-process to etch the sacrificial layer, and to coat the sensitive film on the polysilicon electrodes. The sensitive film that is prepared by a hydrothermal method is made of zinc oxide. The sensor resistance changes when the sensitive film adsorbs or desorbs ammonia gas. The readout circuit is used to convert the sensor resistance into the voltage output. Experiments show that the ammonia sensor has a sensitivity of about 1.5 mV/ppm at room temperature.

  9. A Zinc Oxide Nanorod Ammonia Microsensor Integrated with a Readout Circuit on-a-Chip

    Science.gov (United States)

    Yang, Ming-Zhi; Dai, Ching-Liang; Wu, Chyan-Chyi

    2011-01-01

    A zinc oxide nanorod ammonia microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.35 μm complementary metal oxide semiconductor (CMOS) process was investigated. The structure of the ammonia sensor is composed of a sensitive film and polysilicon electrodes. The ammonia sensor requires a post-process to etch the sacrificial layer, and to coat the sensitive film on the polysilicon electrodes. The sensitive film that is prepared by a hydrothermal method is made of zinc oxide. The sensor resistance changes when the sensitive film adsorbs or desorbs ammonia gas. The readout circuit is used to convert the sensor resistance into the voltage output. Experiments show that the ammonia sensor has a sensitivity of about 1.5 mV/ppm at room temperature. PMID:22247656

  10. Functional proteomics on zinc-dependent metalloproteinases using inhibitor probes

    NARCIS (Netherlands)

    Klein, Theo; Geurink, Paul P.; Overkleeft, Hermen S.; Kauffman, Henk K.; Bischoff, Rainer

    2009-01-01

    Metzincins ore a family of zinc(II)-dependent metolloproteinases with well known members such as the matrix metalloproteinases (MMPs) and A disintegrin and metalloproteinases (ADAMs). Metzincins are largely responsible for the modulation and regulation of the extracellular matrix by proteolytic degr

  11. Functional proteomics on zinc-dependent metalloproteinases using inhibitor probes

    NARCIS (Netherlands)

    Klein, Theo; Geurink, Paul P.; Overkleeft, Hermen S.; Kauffman, Henk K.; Bischoff, Rainer

    Metzincins ore a family of zinc(II)-dependent metolloproteinases with well known members such as the matrix metalloproteinases (MMPs) and A disintegrin and metalloproteinases (ADAMs). Metzincins are largely responsible for the modulation and regulation of the extracellular matrix by proteolytic

  12. Interaction Between Yeasts and Zinc

    Science.gov (United States)

    Nicola, Raffaele De; Walker, Graeme

    Zinc is an essential trace element in biological systems. For example, it acts as a cellular membrane stabiliser, plays a critical role in gene expression and genome modification and activates nearly 300 enzymes, including alcohol dehydrogenase. The present chapter will be focused on the influence of zinc on cell physiology of industrial yeast strains of Saccharomyces cerevisiae, with special regard to the uptake and subsequent utilisation of this metal. Zinc uptake by yeast is metabolism-dependent, with most of the available zinc translocated very quickly into the vacuole. At cell division, zinc is distributed from mother to daughter cells and this effectively lowers the individual cellular zinc concentration, which may become zinc depleted at the onset of the fermentation. Zinc influences yeast fermentative performance and examples will be provided relating to brewing and wine fermentations. Industrial yeasts are subjected to several stresses that may impair fermentation performance. Such stresses may also impact on yeast cell zinc homeostasis. This chapter will discuss the practical implications for the correct management of zinc bioavailability for yeast-based biotechnologies aimed at improving yeast growth, viability, fermentation performance and resistance to environmental stresses

  13. Zinc homeostasis and neurodegenerative disorders

    Directory of Open Access Journals (Sweden)

    Bernadeta eSzewczyk

    2013-07-01

    Full Text Available Zinc is an essential trace element, whose importance to the function of the central nervous system (CNS is increasingly being appreciated. Alterations in zinc dyshomeostasis has been suggested as a key factor in the development of several neuropsychiatric disorders. In the CNS, zinc occurs in two forms: the first being tightly bound to proteins and, secondly, the free, cytoplasmic or extracellular form found in presynaptic vesicles. Under normal conditions, zinc released from the synaptic vesicles modulates both ionotropic and metabotropic post-synaptic receptors. While under clinical conditions such as traumatic brain injury, stroke or epilepsy, the excess influx of zinc into neurons has been found to result in neurotoxicity and damage to postsynaptic neurons. On the other hand, a growing body of evidence suggests that a deficiency, rather than an excess, of zinc leads to an increased risk for the development of neurological disorders. Indeed, zinc deficiency has been shown to affect neurogenesis and increase neuronal apoptosis, which can lead to learning and memory deficits. Altered zinc homeostasis is also suggested as a risk factor for depression, Alzheimer’s disease, aging and other neurodegenerative disorders. Under normal CNS physiology, homeostatic controls are put in place to avoid the accumulation of excess zinc or its deficiency. This cellular zinc homeostasis results from the actions of a coordinated regulation effected by different proteins involved in the uptake, excretion and intracellular storage/trafficking of zinc. These proteins include membranous transporters (ZnT and Zip and metallothioneins (MT which control intracellular zinc levels. Interestingly, alterations in ZnT and MT have been recently reported in both aging and Alzheimer’s disease. This paper provides an overview of both clinical and experimental evidence that implicates a dysfunction in zinc homeostasis in the pathophysiology of depression, Alzheimer

  14. Pinacol Coupling Reactions Catalyzed by Active Zinc

    Institute of Scientific and Technical Information of China (English)

    Hui ZHAO; Wei DENG; Qing Xiang GUO

    2005-01-01

    Pinacol coupling reactions catalyzed by active zinc revealed high activity and extensive suitability. The efficiency of the reaction was improved apparently owing to decreasing reductive potential of zinc. In addition, the results indicated that the zinc activity has a direct relation to the coupling reactivity compared to untreated zinc or other general active zinc.

  15. Effect of the linkers between the zinc fingers in zinc finger protein 809 on gene silencing and nuclear localization

    Energy Technology Data Exchange (ETDEWEB)

    Ichida, Yu, E-mail: ichida-y@ncchd.go.jp; Utsunomiya, Yuko; Onodera, Masafumi

    2016-03-18

    Zinc finger protein 809 (ZFP809) belongs to the Kruppel-associated box-containing zinc finger protein (KRAB-ZFP) family and functions in repressing the expression of Moloney murine leukemia virus (MoMLV). ZFP809 binds to the primer-binding site (PBS)located downstream of the MoMLV-long terminal repeat (LTR) and induces epigenetic modifications at integration sites, such as repressive histone modifications and de novo DNA methylation. KRAB-ZFPs contain consensus TGEKP linkers between C2H2 zinc fingers. The phosphorylation of threonine residues within linkers leads to the inactivation of zinc finger binding to target sequences. ZFP809 also contains consensus linkers between zinc fingers. However, the function of ZFP809 linkers remains unknown. In the present study, we constructed ZFP809 proteins containing mutated linkers and examined their ability to silence transgene expression driven by MLV, binding ability to MLV PBS, and cellular localization. The results of the present study revealed that the linkers affected the ability of ZFP809 to silence transgene expression. Furthermore, this effect could be partly attributed to changes in the localization of ZFP809 proteins containing mutated linkers. Further characterization of ZFP809 linkers is required for understanding the functions and features of KRAB-ZFP-containing linkers. - Highlights: • ZFP809 has three consensus linkers between the zinc fingers. • Linkers are required for ZFP809 to silence transgene expression driven by MLV-LTR. • Linkers affect the precise nuclear localization of ZFP809.

  16. DMPD: Zinc in human health: effect of zinc on immune cells. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18385818 Zinc in human health: effect of zinc on immune cells. Prasad AS. Mol Med. ...2008 May-Jun;14(5-6):353-7. (.png) (.svg) (.html) (.csml) Show Zinc in human health: effect of zinc on immun...e cells. PubmedID 18385818 Title Zinc in human health: effect of zinc on immune cells. Authors Prasad AS. Pu

  17. Zinc oxide doped graphene oxide films for gas sensing applications

    Science.gov (United States)

    Chetna, Kumar, Shani; Garg, A.; Chowdhuri, A.; Dhingra, V.; Chaudhary, S.; Kapoor, A.

    2016-05-01

    Graphene Oxide (GO) is analogous to graphene, but presence of many functional groups makes its physical and chemical properties essentially different from those of graphene. GO is found to be a promising material for low cost fabrication of highly versatile and environment friendly gas sensors. Selectivity, reversibility and sensitivity of GO based gas sensor have been improved by hybridization with Zinc Oxide nanoparticles. The device is fabricated by spin coating of deionized water dispersed GO flakes (synthesized using traditional hummer's method) doped with Zinc Oxide on standard glass substrate. Since GO is an insulator and functional groups on GO nanosheets play vital role in adsorbing gas molecules, it is being used as an adsorber. Additionally, on being exposed to certain gases the electric and optical characteristics of GO material exhibit an alteration in behavior. For the conductivity, we use Zinc Oxide, as it displays a high sensitivity towards conduction. The effects of the compositions, structural defects and morphologies of graphene based sensing layers and the configurations of sensing devices on the performances of gas sensors were investigated by Raman Spectroscopy, X-ray diffraction(XRD) and Keithley Sourcemeter.

  18. Zinc oxide doped graphene oxide films for gas sensing applications

    Energy Technology Data Exchange (ETDEWEB)

    Chetna,, E-mail: chetna2288@gmail.com; Kumar, Shani; Chaudhary, S.; Kapoor, A. [Department of Electronic Science, University of Delhi South Campus, Benito Juarez Road, New Delhi-110021 (India); Garg, A.; Chowdhuri, A.; Dhingra, V. [Department of Electronic Science, Acharya Narendra Dev College, University of Delhi, Kalkaji, New Delhi- 110019 (India)

    2016-05-06

    Graphene Oxide (GO) is analogous to graphene, but presence of many functional groups makes its physical and chemical properties essentially different from those of graphene. GO is found to be a promising material for low cost fabrication of highly versatile and environment friendly gas sensors. Selectivity, reversibility and sensitivity of GO based gas sensor have been improved by hybridization with Zinc Oxide nanoparticles. The device is fabricated by spin coating of deionized water dispersed GO flakes (synthesized using traditional hummer’s method) doped with Zinc Oxide on standard glass substrate. Since GO is an insulator and functional groups on GO nanosheets play vital role in adsorbing gas molecules, it is being used as an adsorber. Additionally, on being exposed to certain gases the electric and optical characteristics of GO material exhibit an alteration in behavior. For the conductivity, we use Zinc Oxide, as it displays a high sensitivity towards conduction. The effects of the compositions, structural defects and morphologies of graphene based sensing layers and the configurations of sensing devices on the performances of gas sensors were investigated by Raman Spectroscopy, X-ray diffraction(XRD) and Keithley Sourcemeter.

  19. Molecular Cloning and Expression Analysis of a Cys2/His2 Type Zinc Finger Protein Gene in Upland Cotton

    Institute of Scientific and Technical Information of China (English)

    YANG Yu-wen; NI Wan-chao; ZHANG Bao-long; SHEN Xin-lian

    2008-01-01

    @@ The zinc finger proteins belong to the largest family of transcription factors.But there is little research of Cys2/His2 type zinc finger proteins in cotton,and there is no submission of correlating ESTs to GenBank.In this study,a full length of one Cys2/His2 type zinc finger protein (GZFP) and its 5 flanking sequence were obtained by RT-PCR and tail PCR.

  20. Fluorescence lifetime-based biosensing of zinc: Origin of the broad dynamic range.

    Science.gov (United States)

    Thompson, R B; Patchan, M W

    1995-06-01

    Fluorescence lifetime-based chemical sensors have recently been described for applications in medicine, environmental monitoring, and bioprocess control. These sensors transduce the level of the analyte as a change in the apparent fluorescence lifetime of an indicator phase. We have previously developed a wavelength-ratiometric fluorescence biosensor for zinc based on binding of zinc and dansylamide to apo-carbonic anhydrase which exhibited high sensitivity and selectivity. We demonstrate that the apo-carbonic anhydrase/dansylamide indicator system is very well suited for lifetime-based sensing, with a subnanomolar detection limit and greater than 1000-fold dynamic range. The theoretical basis for the wide dynamic range is discussed.

  1. Advanced Wireless Sensor Nodes - MSFC

    Science.gov (United States)

    Varnavas, Kosta; Richeson, Jeff

    2017-01-01

    NASA field center Marshall Space Flight Center (Huntsville, AL), has invested in advanced wireless sensor technology development. Developments for a wireless microcontroller back-end were primarily focused on the commercial Synapse Wireless family of devices. These devices have many useful features for NASA applications, good characteristics and the ability to be programmed Over-The-Air (OTA). The effort has focused on two widely used sensor types, mechanical strain gauges and thermal sensors. Mechanical strain gauges are used extensively in NASA structural testing and even on vehicle instrumentation systems. Additionally, thermal monitoring with many types of sensors is extensively used. These thermal sensors include thermocouples of all types, resistive temperature devices (RTDs), diodes and other thermal sensor types. The wireless thermal board will accommodate all of these types of sensor inputs to an analog front end. The analog front end on each of the sensors interfaces to the Synapse wireless microcontroller, based on the Atmel Atmega128 device. Once the analog sensor output data is digitized by the onboard analog to digital converter (A/D), the data is available for analysis, computation or transmission. Various hardware features allow custom embedded software to manage battery power to enhance battery life. This technology development fits nicely into using numerous additional sensor front ends, including some of the low-cost printed circuit board capacitive moisture content sensors currently being developed at Auburn University.

  2. Depleted zinc: Properties, application, production.

    Science.gov (United States)

    Borisevich, V D; Pavlov, A V; Okhotina, I A

    2009-01-01

    The addition of ZnO, depleted in the Zn-64 isotope, to the water of boiling water nuclear reactors lessens the accumulation of Co-60 on the reactor interior surfaces, reduces radioactive wastes and increases the reactor service-life because of the inhibitory action of zinc on inter-granular stress corrosion cracking. To the same effect depleted zinc in the form of acetate dihydrate is used in pressurized water reactors. Gas centrifuge isotope separation method is applied for production of depleted zinc on the industrial scale. More than 20 years of depleted zinc application history demonstrates its benefits for reduction of NPP personnel radiation exposure and combating construction materials corrosion.

  3. Chloroquine is a zinc ionophore.

    Directory of Open Access Journals (Sweden)

    Jing Xue

    Full Text Available Chloroquine is an established antimalarial agent that has been recently tested in clinical trials for its anticancer activity. The favorable effect of chloroquine appears to be due to its ability to sensitize cancerous cells to chemotherapy, radiation therapy, and induce apoptosis. The present study investigated the interaction of zinc ions with chloroquine in a human ovarian cancer cell line (A2780. Chloroquine enhanced zinc uptake by A2780 cells in a concentration-dependent manner, as assayed using a fluorescent zinc probe. This enhancement was attenuated by TPEN, a high affinity metal-binding compound, indicating the specificity of the zinc uptake. Furthermore, addition of copper or iron ions had no effect on chloroquine-induced zinc uptake. Fluorescent microscopic examination of intracellular zinc distribution demonstrated that free zinc ions are more concentrated in the lysosomes after addition of chloroquine, which is consistent with previous reports showing that chloroquine inhibits lysosome function. The combination of chloroquine with zinc enhanced chloroquine's cytotoxicity and induced apoptosis in A2780 cells. Thus chloroquine is a zinc ionophore, a property that may contribute to chloroquine's anticancer activity.

  4. Zinc In CCl4 Toxicity

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective To investigate the protective effect of zinc in CCl4-induced hepatotoxicity. Methods Rats were treated with zinc acetate for four days. The zinc doses were 5 mg Zn/kg and 10 mg Zn/kg body weight respectively. Two groups of the zinc acetate-treated rats were later challenged with a single dose of CCl4 (1.5 mL/kg body weight). Results Compared to control animals, the plasma of rats treated with CCl4 showed hyperbilirubinaemia, hypoglycaemia, hypercreatinaemia and hypoproteinaemia. When the animals were however supplemented with zinc in form of zinc acetate before being dosed with CCl4, the 5 mg Zn/kg body weight of zinc acetate reversed the hypoproteinaemia induced by CCl4, whereas the 10mg Zn/kg body weight of zinc acetate reversed the hypoglycaemia, hyperbilimbinaemia and hypercreatinaemia induced by CCl4. Conclusion The 10mug Zn/kg body weight of zinc acetate is more consistent in protecting against CCl4 hepatotoxicity. The possible mechanisms of protection are highlighted.

  5. Effects of Foliar Application of Nano Zinc Chelate and Zinc Sulfate on Zinc Content, Pigments and Photosynthetic Indices of Holy Basil (Ocimum sanctum(

    Directory of Open Access Journals (Sweden)

    Zohreh Moghimi pour

    2017-02-01

    Full Text Available Introduction: Holy basil is a perennial plant belongs to Lamiaceae family. The plant is a perennial and thrives well in the hot and humid climate. Its aerial parts have been in use for food, pharmaceuticals, cosmetics and perfumery industries. Leaves contain 0.5-1.5% essential oil and main oil components are eugenol, methyl eugenol, carvacrol, methyl chavicol and1,8-cineole. A balanced fertilization program with macro and micronutrients is very important in producing high quality yield. Zinc is involved in IAA production, chlorophyll biosynthesis, carbon assimilation, saccharids accumulation, reactive oxygen radicals scavenging and finally carbon utilization in volatile oil biosynthesis. Material and methods: In order to evaluate the effect on zinc foliar application on zinc content of leaves, photosynthetic indices and pigments of holy basil, an experiment was carried out in 2013 at a research farm of Horticultural Science, Shahid Chamran University (31°20'N latitude and 48°40'E longitude and 22.5 m mean sea level, Ahvaz (Iran, a region characterized by semi-dry climate. The experiment was arranged based on Randomized Complete Block Design (RCBD with six treatments and three replications. The treatments were nano zinc chelate (0, 0.5, 1 and 1.5 g.l-1 and zinc sulfate (1 and 1.5 g.l-1 fertilizers. Land preparation includes disking and the formation of raising beds (15cm high and 45cm wide across the top using a press-pan-type bed shaper. Holy basil seeds were sown on two rows on each bed, with 15 cm in-row and 40 cm between-row spacing. The plants were irrigated weekly as needed. Foliar application of zinc fertilizers was done at six-eight leaf stage and were repeated with interval 15 days until full bloom stage. Zinc content, stomata conductance (gs, CO2 under stomata (Ci, transpiration rate (E, net photosynthesis (Pn, light use efficiency (LUE, water use efficiency (WUE and also chlorophyll a, chlorophyll b, chlorophyll a+b and carotenoid

  6. Metamaterial Sensors

    Directory of Open Access Journals (Sweden)

    Jing Jing Yang

    2013-01-01

    Full Text Available Metamaterials have attracted a great deal of attention due to their intriguing properties, as well as the large potential applications for designing functional devices. In this paper, we review the current status of metamaterial sensors, with an emphasis on the evanescent wave amplification and the accompanying local field enhancement characteristics. Examples of the sensors are given to illustrate the principle and the performance of the metamaterial sensor. The paper concludes with an optimistic outlook regarding the future of metamaterial sensor.

  7. Modulation of Zinc Homeostasis in Acanthamoeba castellanii as a Possible Antifungal Strategy against Cryptococcus gattii

    Directory of Open Access Journals (Sweden)

    Nicole S. Ribeiro

    2017-08-01

    Full Text Available Cryptococcus gattii is a basidiomycetous yeast that can be found in the environment and is one of the agents of cryptococcosis, a life-threatening disease. During its life cycle, cryptococcal cells take hold inside environmental predators such as amoebae. Despite their evolutionary distance, macrophages and amoebae share conserved similar steps of phagocytosis and microbial killing. To evaluate whether amoebae also share other antifungal strategies developed by macrophages, we investigated nutritional immunity against cryptococcal cells. We focused on zinc homeostasis modulation in Acanthamoeba castellanii infected with C. gattii. The intracellular proliferation rate (IPR in amoebae was determined using C. gattii R265 and mutants for the ZIP1 gene, which displays defects of growth in zinc-limiting conditions. We detected a reduced IPR in cells lacking the ZIP1 gene compared to wild-type strains, suggesting that amoebae produce a low zinc environment to engulfed cells. Furthermore, flow cytometry analysis employing the zinc probe Zinpyr-1 confirmed the reduced concentration of zinc in cryptococcal-infected amoebae. qRT-PCR analysis of zinc transporter-coding genes suggests that zinc export by members of the ZnT family would be involved in the reduced intracellular zinc concentration. These results indicate that amoebae may use nutritional immunity to reduce fungal cell proliferation by reducing zinc availability for the pathogen.

  8. A simple liposome assay for the screening of zinc ionophore activity of polyphenols.

    Science.gov (United States)

    Clergeaud, Gael; Dabbagh-Bazarbachi, Husam; Ortiz, Mayreli; Fernández-Larrea, Juan B; O'Sullivan, Ciara K

    2016-04-15

    An efficient liposomal system for screening the zinc ionophore activity of a selected library consisting of the most relevant dietary polyphenols is presented. The zinc ionophore activity was demonstrated by exploring the use of zinc-specific fluorophore FluoZin-3 loaded liposomes as simple membrane tools that mimic the cell membrane. The zinc ionophore activity was demonstrated as the capacity of polyphenols to transport zinc cations across the liposome membrane and increase the zinc-specific fluorescence of the encapsulated fluorophore FluoZin-3. In addition, the zinc chelation strength of the polyphenols was also tested in a competition assay based on the fluorescence quenching of zinc-dependent fluorescence emitted by zinc-FluoZin-3 complex. Finally, the correlation between the chelation capacity and ionophore activity is demonstrated, thus underlining the sequestering or ionophoric activity that the phenolic compounds can display, thus, providing better knowledge of the importance of the structural conformation versus their biological activity. Furthermore, the assays developed can be used as tools for rapid, high-throughput screening of families of polyphenols towards different biometals.

  9. Zinc supplementation for tinnitus.

    Science.gov (United States)

    Person, Osmar C; Puga, Maria Es; da Silva, Edina Mk; Torloni, Maria R

    2016-11-23

    Tinnitus is the perception of sound without external acoustic stimuli. Patients with severe tinnitus may have physical and psychological complaints and their tinnitus can cause deterioration in their quality of life. At present no specific therapy for tinnitus has been found to be satisfactory in all patients. In recent decades, a number of reports have suggested that oral zinc supplementation may be effective in the management of tinnitus. Since zinc has a role in cochlear physiology and in the synapses of the auditory system, there is a plausible mechanism of action for this treatment. To evaluate the effectiveness and safety of oral zinc supplementation in the management of patients with tinnitus. The Cochrane ENT Information Specialist searched the ENT Trials Register; Central Register of Controlled Trials (CENTRAL 2016, Issue 6); PubMed; EMBASE; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 14 July 2016. Randomised controlled trials comparing zinc supplementation versus placebo in adults (18 years and over) with tinnitus. We used the standard methodological procedures recommended by Cochrane. Our primary outcome measures were improvement in tinnitus severity and disability, measured by a validated tinnitus-specific questionnaire, and adverse effects. Secondary outcomes were quality of life, change in socioeconomic impact associated with work, change in anxiety and depression disorders, change in psychoacoustic parameters, change in tinnitus loudness, change in overall severity of tinnitus and change in thresholds on pure tone audiometry. We used GRADE to assess the quality of the evidence for each outcome; this is indicated in italics. We included three trials involving a total of 209 participants. The studies were at moderate to high risk of bias. All included studies had differences in participant selection criteria, length of follow-up and outcome measurement

  10. Attention Sensor

    NARCIS (Netherlands)

    Börner, Dirk; Kalz, Marco; Specht, Marcus

    2014-01-01

    This software sketch was used in the context of an experiment for the PhD project “Ambient Learning Displays”. The sketch comprises a custom-built attention sensor. The sensor measured (during the experiment) whether a participant looked at and thus attended a public display. The sensor was built us

  11. Attention Sensor

    NARCIS (Netherlands)

    Börner, Dirk; Kalz, Marco; Specht, Marcus

    2014-01-01

    This software sketch was used in the context of an experiment for the PhD project “Ambient Learning Displays”. The sketch comprises a custom-built attention sensor. The sensor measured (during the experiment) whether a participant looked at and thus attended a public display. The sensor was built us

  12. Inhibitory zinc-enriched terminals in mouse spinal cord

    DEFF Research Database (Denmark)

    Danscher, G; Jo, S M; Varea, E;

    2001-01-01

    The ultrastructural localization of zinc transporter-3, glutamate decarboxylase and zinc ions in zinc-enriched terminals in the mouse spinal cord was studied by zinc transporter-3 and glutamate decarboxylase immunohistochemistry and zinc selenium autometallography, respectively.The distribution...

  13. Zinc absorption by young adults from supplemental zinc citrate is comparable with that from zinc gluconate and higher than from zinc oxide.

    Science.gov (United States)

    Wegmüller, Rita; Tay, Fabian; Zeder, Christophe; Brnic, Marica; Hurrell, Richard F

    2014-02-01

    The water-soluble zinc salts gluconate, sulfate, and acetate are commonly used as supplements in tablet or syrup form to prevent zinc deficiency and to treat diarrhea in children in combination with oral rehydration. Zinc citrate is an alternative compound with high zinc content, slightly soluble in water, which has better sensory properties in syrups but no absorption data in humans. We used the double-isotope tracer method with (67)Zn and (70)Zn to measure zinc absorption from zinc citrate given as supplements containing 10 mg of zinc to 15 healthy adults without food and compared absorption with that from zinc gluconate and zinc oxide (insoluble in water) using a randomized, double-masked, 3-way crossover design. Median (IQR) fractional absorption of zinc from zinc citrate was 61.3% (56.6-71.0) and was not different from that from zinc gluconate with 60.9% (50.6-71.7). Absorption from zinc oxide at 49.9% (40.9-57.7) was significantly lower than from both other supplements (P zinc oxide. We conclude that zinc citrate, given as a supplement without food, is as well absorbed by healthy adults as zinc gluconate and may thus be a useful alternative for preventing zinc deficiency and treating diarrhea. The more insoluble zinc oxide is less well absorbed when given as a supplement without food and may be minimally absorbed by some individuals. This trial was registered at clinicaltrials.gov as NCT01576627.

  14. El zinc: oligoelemento esencial

    Directory of Open Access Journals (Sweden)

    C. Rubio

    Full Text Available En este artículo se hace una revisión exhaustiva del zinc, elemento metálico esencial para el funcionamiento del organismo. Repasamos y reflejamos aspectos relacionados con la farmacocinética, con las fuentes dietéticas más importantes, así como las IDR (Ingestas Dietéticas Recomendadas del mismo. También se hace mención a los signos y síntomas relacionados tanto con una ingesta deficiente, como con posibles efectos tóxicos, derivados de ingestas excesivas.

  15. Zinc Base Die Castings

    Science.gov (United States)

    1935-01-31

    183 B86- 33T SAE N.J .zn Co. B86-33T 1934 SAE N.J.Zn Cc,. Zamak 3N AllO;E Cl C2 Allo~ XXI 221 Zarnak 2 .A.llo;z XXIII .Allol XXIII 202 Zamak 2 O...2 includ.es Pb ,Fe, Cd, C:’. 3 special high gra1e ?:inc. • t • • ; -J TABLE II Chemical Composition for Zinc Alloy Nuuber Zam.ak 2 Zamak 3...was alco given regarding the aging of the alloys. The a1loy3 Aupplied were: Zamak 2, Zamak 3, Zamak 3-S (Stabilized to hasten contraction which

  16. The biology of zinc transport in mammary epithelial cells: implications for mammary gland development, lactation, and involution.

    Science.gov (United States)

    McCormick, Nicholas H; Hennigar, Stephen R; Kiselyov, Kirill; Kelleher, Shannon L

    2014-03-01

    Zinc plays a critical role in a vast array of cellular functions including gene transcription, protein translation, cell proliferation, differentiation, bioenergetics, and programmed cell death. The mammary gland depends upon tight coordination of these processes during development and reproduction for optimal expansion, differentiation, and involution. For example, zinc is required for activation of matrix metalloproteinases, intracellular signaling cascades such as MAPK and PKC, and the activation of both mitochondrial-mediated apoptosis and lysosomal-mediated cell death. In addition to functional needs, during lactation the mammary gland must balance providing optimal zinc for cellular requirements with the need to secrete a substantial amount of zinc into milk to meet the requirements of the developing neonate. Finally, the mammary gland exhibits the most profound example of programmed cell death, which is driven by both apoptotic and lysosomal-mediated cell death. Two families of zinc-specific transporters regulate zinc delivery for these diverse functions. Members of the ZIP family of zinc transporters (ZIP1-14) import zinc into the cytoplasm from outside the cell or from subcellular organelles, while members of the ZnT family (ZnT1-10) export zinc from the cytoplasm. Recently, the ion channel transient receptor potential mucolipin 1 (TRPML1) has also been implicated in zinc transport. Herein, we review our current understanding of the molecular mechanisms through which mammary epithelial cells utilize zinc with a focus on the transport of zinc into discrete subcellular organelles for specific cellular functions during mammary gland development, lactation, and involution.

  17. Danxia Zinc Smelter started construction

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>Zinc smelting project of Danxia Smelting Plant has a total investment of about RMB 4 billion, which is designed by Changsha Engineering & Research Institute of Nonferrous Metallurgy and planned to be implemented in three stages. The first stage 100,000 tons of electrolytic zinc improvement work is planned to be completed by the end of 2008. The second and third stages

  18. [Cloning and structure analysis of zinc finger protein gene in Populus euphratica Oliv].

    Science.gov (United States)

    Wang, Jun-Ying; Yin, Wei-Lun; Xia, Xin-Li

    2005-03-01

    Zinc finger proteins belong to a family of nuclear transcription factors which function is to regulate gene expression in both prokaryotic and eukaryotic cells. A pair of primers was designed after analyzing the conservation of salt-tolerant zinc protein Alfin-1 in such diverse plants as alfalfa and Arabidopsis. The zinc finger protein gene is isolated from total RNA with RT-PCR in aquaculture leaves of Populus euphratica . Its full cDNA length is 924bp. Analysis of its amino acid sequence showed it has a typical Cys(2)/His(2) zinc finger structure and a G-rich promoter binding site GTGGGG, starting from position 556. Since transcrptional factors which have the same function show conservation in structure and amino acid sequence of DNA binding region, the structure analysis in this paper indicates the cloned zinc finger protein gene may have functional correlation to Alfin-1.

  19. The Functions of Metamorphic Metallothioneins in Zinc and Copper Metabolism

    Directory of Open Access Journals (Sweden)

    Artur Krężel

    2017-06-01

    Full Text Available Recent discoveries in zinc biology provide a new platform for discussing the primary physiological functions of mammalian metallothioneins (MTs and their exquisite zinc-dependent regulation. It is now understood that the control of cellular zinc homeostasis includes buffering of Zn2+ ions at picomolar concentrations, extensive subcellular re-distribution of Zn2+, the loading of exocytotic vesicles with zinc species, and the control of Zn2+ ion signalling. In parallel, characteristic features of human MTs became known: their graded affinities for Zn2+ and the redox activity of their thiolate coordination environments. Unlike the single species that structural models of mammalian MTs describe with a set of seven divalent or eight to twelve monovalent metal ions, MTs are metamorphic. In vivo, they exist as many species differing in redox state and load with different metal ions. The functions of mammalian MTs should no longer be considered elusive or enigmatic because it is now evident that the reactivity and coordination dynamics of MTs with Zn2+ and Cu+ match the biological requirements for controlling—binding and delivering—these cellular metal ions, thus completing a 60-year search for their functions. MT represents a unique biological principle for buffering the most competitive essential metal ions Zn2+ and Cu+. How this knowledge translates to the function of other families of MTs awaits further insights into the specifics of how their properties relate to zinc and copper metabolism in other organisms.

  20. Obesity and age-related alterations in the gene expression of zinc-transporter proteins in the human brain

    DEFF Research Database (Denmark)

    Olesen, R H; Hyde, T M; Kleinman, J E

    2016-01-01

    participate in intracellular zinc homeostasis. Altered expression of zinc-regulatory proteins has been described in AD patients. Using microarray data from human frontal cortex (BrainCloud), this study investigates expression of the SCLA30A (ZNT) and SCLA39A (ZIP) families of genes in a Caucasian and African......The incidence of Alzheimer's disease (AD) is increasing. Major risk factors for AD are advancing age and diabetes. Lately, obesity has been associated with an increased risk of dementia. Obese and diabetic individuals are prone to decreased circulating levels of zinc, reducing the amount of zinc...

  1. Zinc transporter 5 and zinc transporter 7 induced by high glucose protects peritoneal mesothelial cells from undergoing apoptosis.

    Science.gov (United States)

    Zhang, Xiuli; Liang, Dan; Guo, Baolei; Deng, Wenyan; Chi, Zhi-Hong; Cai, Yuan; Wang, Lining; Ma, Jianfei

    2013-04-01

    Zinc is an essential micronutrient and cytoprotectant involved in many types of apoptosis. The zinc transporter family SLC30A (ZnTs) is an important factor in the regulation of zinc homeostasis; however, its function in apoptosis in peritoneal mesothelial cells (PMCs) remains unknown. This study explores the regulation of zinc transporters and how they play a role in cell survival, particularly in rat peritoneal mesothelial cells (RPMCs), surrounding glucose concentrations, and the molecular mechanism involved. The messenger RNA (mRNA) transcripts were quantitatively measured by real-time polymerase chain reaction for all known nine zinc transport exporters (SLC30A1-8,10), as well as in primary RPMCs and the cells cultured under nonstimulated and HG-stimulated conditions. While many zinc transporters were constitutively expressed, ZnT5 mRNA and ZnT7 mRNA were strongly induced by HG. Overexpression of ZnT5 and ZnT7 respectively resulted in a decrease in the expression of caspace 3, caspace 8, BAX, and AIF and coincided with cell survival in the presence of HG. Inhibition of ZnT5 and ZnT7 expression using considerable siRNA-mediated knockdown of RPMCs was examined and, afterwards, the impact on cell apoptosis was investigated. Increased levels of apoptosis were observed after knockdown of ZnT5 and ZnT7. Furthermore, overexpression of ZnT5 and ZnT7 is accompanied by activation of PI3K/Akt pathway and inhibiting HG-induced apoptosis. This study suggests that the zinc transporting system in RPMCs is influenced by exposure to HG, particularly ZnT5 and ZnT7. This may account for the inhibition of HG-induced RPMC apoptosis and peritoneum injury, likely through targeting PI3K/Akt pathway-mediated cell survival.

  2. Interferon-inducible p200-family protein IFI16, an innate immune sensor for cytosolic and nuclear double-stranded DNA: regulation of subcellular localization.

    Science.gov (United States)

    Veeranki, Sudhakar; Choubey, Divaker

    2012-01-01

    The interferon (IFN)-inducible p200-protein family includes structurally related murine (for example, p202a, p202b, p204, and Aim2) and human (for example, AIM2 and IFI16) proteins. All proteins in the family share a partially conserved repeat of 200-amino acid residues (also called HIN-200 domain) in the C-terminus. Additionally, most proteins (except the p202a and p202b proteins) also share a protein-protein interaction pyrin domain (PYD) in the N-terminus. The HIN-200 domain contains two consecutive oligosaccharide/oligonucleotide binding folds (OB-folds) to bind double stranded DNA (dsDNA). The PYD domain in proteins allows interactions with the family members and an adaptor protein ASC. Upon sensing cytosolic dsDNA, Aim2, p204, and AIM2 proteins recruit ASC protein to form an inflammasome, resulting in increased production of proinflammatory cytokines. However, IFI16 protein can sense cytosolic as well as nuclear dsDNA. Interestingly, the IFI16 protein contains a nuclear localization signal (NLS). Accordingly, the initial studies had indicated that the endogenous IFI16 protein is detected in the nucleus and within the nucleus in the nucleolus. However, several recent reports suggest that subcellular localization of IFI16 protein in nuclear versus cytoplasmic (or both) compartment depends on cell type. Given that the IFI16 protein can sense cytosolic as well as nuclear dsDNA and can initiate different innate immune responses (production of IFN-β versus proinflammatory cytokines), here we evaluate the experimental evidence for the regulation of subcellular localization of IFI16 protein in various cell types. We conclude that further studies are needed to understand the molecular mechanisms that regulate the subcellular localization of IFI16 protein. Published by Elsevier Ltd.

  3. 21 CFR 73.1991 - Zinc oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Zinc oxide. 73.1991 Section 73.1991 Food and Drugs... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1991 Zinc oxide. (a) Identity. (1) The color additive zinc...). It is principally composed of Zn. (2) Color additive mixtures for drug use made with zinc oxide...

  4. Sensor Compendium

    CERN Document Server

    Artuso, M; Bolla, G; Bortoletto, D; Caberera, B; Carlstrom, J E; Chang, C L; Cooper, W; Da Via, C; Demarteau, M; Fast, J; Frisch, H; Garcia-Sciveres, M; Golwala, S; Haber, C; Hall, J; Hoppe, E; Irwin, K D; Kagan, H; Kenney, C; Lee, A T; Lynn, D; Orrell, J; Pyle, M; Rusack, R; Sadrozinski, H; Sanchez, M C; Seiden, A; Trischuk, W; Vavra, J; Wetstein, M; Zhu, R-Y

    2013-01-01

    Sensors play a key role in detecting both charged particles and photons for all three frontiers in Particle Physics. The signals from an individual sensor that can be used include ionization deposited, phonons created, or light emitted from excitations of the material. The individual sensors are then typically arrayed for detection of individual particles or groups of particles. Mounting of new, ever higher performance experiments, often depend on advances in sensors in a range of performance characteristics. These performance metrics can include position resolution for passing particles, time resolution on particles impacting the sensor, and overall rate capabilities. In addition the feasible detector area and cost frequently provides a limit to what can be built and therefore is often another area where improvements are important. Finally, radiation tolerance is becoming a requirement in a broad array of devices. We present a status report on a broad category of sensors, including challenges for the future ...

  5. Zinc-bromine battery development

    Science.gov (United States)

    Richards, Lew; Vanschalwijk, Walter; Albert, George; Tarjanyi, Mike; Leo, Anthony; Lott, Stephen

    1990-05-01

    This report describes development activities on the zinc-bromine battery system conducted by Energy Research Corporation (ERC). The project was a cost-shared program supported by the U.S. Department of Energy and managed through Sandia. The project began in September 1985 and ran through January 1990. The zinc-bromine battery has been identified as a promising alternative to conventional energy storage options for many applications. The low cost of the battery reactants and the potential for long life make the system an attractive candidate for bulk energy storage applications, such as utility load leveling. The battery stores energy by the electrolysis of an aqueous zinc bromide salt to zinc metal and dissolved bromine. Zinc is plated as a layer on the electrode surface while bromine is dissolved in the electrolyte and carried out of the stack. The bromine is then extracted from the electrolyte with an organic complexing agent in the positive electrolyte storage tank. On discharge the zinc and bromine are consumed, regenerating the zinc bromide salt.

  6. The (unusual) aspartic acid in the metal coordination sphere of the prokaryotic zinc finger domain.

    Science.gov (United States)

    D'Abrosca, Gianluca; Russo, Luigi; Palmieri, Maddalena; Baglivo, Ilaria; Netti, Fortuna; de Paola, Ivan; Zaccaro, Laura; Farina, Biancamaria; Iacovino, Rosa; Pedone, Paolo Vincenzo; Isernia, Carla; Fattorusso, Roberto; Malgieri, Gaetano

    2016-08-01

    The possibility of choices of protein ligands and coordination geometries leads to diverse Zn(II) binding sites in zinc-proteins, allowing a range of important biological roles. The prokaryotic Cys2His2 zinc finger domain (originally found in the Ros protein from Agrobacterium tumefaciens) tetrahedrally coordinates zinc through two cysteine and two histidine residues and it does not adopt a correct fold in the absence of the metal ion. Ros is the first structurally characterized member of a family of bacterial proteins that presents several amino acid changes in the positions occupied in Ros by the zinc coordinating residues. In particular, the second position is very often occupied by an aspartic acid although the coordination of structural zinc by an aspartate in eukaryotic zinc fingers is very unusual. Here, by appropriately mutating the protein Ros, we characterize the aspartate role within the coordination sphere of this family of proteins demonstrating how the presence of this residue only slightly perturbs the functional structure of the prokaryotic zinc finger domain while it greatly influences its thermodynamic properties.

  7. Wind Sensor

    OpenAIRE

    Li, Jiaoyang; Ni, Jiqin

    2014-01-01

    Wind measurement is needed in many practical and scientific research situations. Some specific applications require to precisely measuring both wind direction and wind speed at the same time. Current commercial sensors for wind direction and wind speed measurement usually use ultrasonic technology and the sensors are very expensive (> $1500). In addition, the sensors are large in dimension and cannot measure airflow patterns in high spatial resolution. Therefore new and low cost wind speed an...

  8. Cytotoxicity of zinc in vitro.

    Science.gov (United States)

    Borovanský, J; Riley, P A

    1989-01-01

    The effect of zinc ions on B16 mouse melanoma lines, HeLa cells and I-221 epithelial cells was investigated in vitro in order to ascertain whether sensitivity to Zn2+ is a general feature of cells in vitro and in an attempt to elucidate the mechanism(s) of zinc cytotoxicity. The proliferation of B16, HeLa and I-221 cell lines was inhibited by 1.25 x 10(-4), 1.50 x 10(-4) and 1.50 x 10(-4) mol/l Zn2+, respectively. The free radical scavengers, methimazole and ethanol, did not suppress the toxicity of Zn2+, neither did superoxide dismutase or catalase. The addition of the chelating agent EDTA reduced the zinc cytotoxicity. It was possible to suppress the cytotoxicity of zinc by increasing the concentration of either Fe2+ or Ca2+ but not Mg2+, which suggests that a prerequisite for the toxic action of zinc is entry into cells using channels that are shared with iron or calcium. This view was supported by experiments in which transferrin intensified the cytotoxic action of zinc in serum-free medium. Another agent facilitating zinc transport, prostaglandin E2, inhibited the proliferation of the B16 melanoma cell line. There were no conspicuous differences in zinc toxicity to pigmented and unpigmented cells. The toxic effect of zinc in the cell systems studied exceeded that of iron, copper, manganese and cobalt in the same concentration range. In vitro, Zn2+ should be regarded as a dangerous cation.

  9. Evaluating Zeolite-Modified Sensors: towards a faster set of chemical sensors

    Science.gov (United States)

    Berna, A. Z.; Vergara, A.; Trincavelli, M.; Huerta, R.; Afonja, A.; Parkin, I. P.; Binions, R.; Trowell, S.

    2011-09-01

    The responses of zeolite-modified sensors, prepared by screen printing layers of chromium titanium oxide (CTO), were compared to unmodified tin oxide sensors using amplitude and transient responses. For transient responses we used a family of features, derived from the exponential moving average (EMA), to characterize chemo-resistive responses. All sensors were tested simultaneously against 20 individual volatile compounds from four chemical groups. The responses of the two types of sensors showed some independence. The zeolite-modified CTO sensors discriminated compounds better using either amplitude response or EMA features and CTO-modified sensors also responded three times faster.

  10. Gas Sensor

    KAUST Repository

    Luebke, Ryan

    2015-01-22

    A gas sensor using a metal organic framework material can be fully integrated with related circuitry on a single substrate. In an on-chip application, the gas sensor can result in an area-efficient fully integrated gas sensor solution. In one aspect, a gas sensor can include a first gas sensing region including a first pair of electrodes, and a first gas sensitive material proximate to the first pair of electrodes, wherein the first gas sensitive material includes a first metal organic framework material.

  11. Sensor web

    Science.gov (United States)

    Delin, Kevin A. (Inventor); Jackson, Shannon P. (Inventor)

    2011-01-01

    A Sensor Web formed of a number of different sensor pods. Each of the sensor pods include a clock which is synchronized with a master clock so that all of the sensor pods in the Web have a synchronized clock. The synchronization is carried out by first using a coarse synchronization which takes less power, and subsequently carrying out a fine synchronization to make a fine sync of all the pods on the Web. After the synchronization, the pods ping their neighbors to determine which pods are listening and responded, and then only listen during time slots corresponding to those pods which respond.

  12. Enhanced fabrication process of zinc oxide nanowires for optoelectronics

    Energy Technology Data Exchange (ETDEWEB)

    García Núñez, C., E-mail: carlos.garcia@uam.es [Grupo de Electrónica y Semiconductores, Departamento de Física Aplicada, Universidad Autónoma de Madrid, 28049 Madrid (Spain); Pau, J.L.; Ruíz, E.; García Marín, A.; García, B.J.; Piqueras, J. [Grupo de Electrónica y Semiconductores, Departamento de Física Aplicada, Universidad Autónoma de Madrid, 28049 Madrid (Spain); Shen, G.; Wilbert, D.S.; Kim, S.M.; Kung, P. [Department of Electrical and Computer Engineering, the University of Alabama, Tuscaloosa, AL 35487 (United States)

    2014-03-31

    Zinc oxide (ZnO) nanowires (NWs) based ultraviolet (UV) sensors have been fabricated using different assembly techniques to form functional structures, aiming at the improvement of the performance of NW-based sensors for optoelectronic applications. NWs with diameters and lengths varying between 90–870 nm and 2–20 μm, respectively, were synthesized by controlling the growth conditions in a chemical vapor transport system. Optical properties of NWs were studied by means of transmission spectroscopy. Electrical properties of single ZnO NW-based sensors were analyzed in dark and under UV illumination (at photon wavelength of λ < 370 nm) as a function of the NW diameter. Results of the study indicate that reduction of the NW diameter below 200 nm leads to an improvement of the photocurrent (at λ < 370 nm) up to 10{sup 2} μA and a decrease of the decay time around 150 s. These enhancements may help to improve the performance of ZnO-based optoelectronic devices. - Highlights: • ZnO nanowires (NWs) with diameters 90–870 nm were grown by chemical vapor transport. • ZnO NWs showed strong absorption in the UV range. • Different assembly techniques were tested for preparing ZnO NW-based UV sensors. • Sensor photoresponses were around 10{sup 3} A/W. • Reducing NW diameter below 200 nm improved sensor photosensitivity.

  13. Zinc oxide piezoelectric nano-generators for low frequency applications

    Science.gov (United States)

    Nour, E. S.; Nur, O.; Willander, M.

    2017-06-01

    Piezoelectric Zinc Oxide (ZnO) nanogenerators (NGs) have been fabricated for low frequency (work as a triggered sensor for a wireless system using footstep pressure. These studies demonstrate the feasibility of using a ZnO NWs piezoelectric NG as a low-frequency self- powered sensor, with potential applications in wireless sensor networks. After that, we investigated and fabricated a sensor on a PEDOT: PSS plastic substrate using a one-sided growth and double-sided growth technique. For the first growth technique, the fabricated NG has been used as a sensor for an acceleration system; while the fabricated NG by the second technique works as an anisotropic direction sensor. This fabricated configuration showed stability for sensing and can be used in surveillance, security, and auto-Mobil applications. In addition to that, we investigated the fabrication of a sandwiched NG on plastic substrates. Finally, we demonstrated that doping ZnO NWs with extrinsic elements (such as Ag) will lead to the reduction of the piezoelectric effect due to the loss of crystal symmetry. A brief summary into future opportunities and challenges is also presented.

  14. Zinc Oxide Nanoparticle Photodetector

    Directory of Open Access Journals (Sweden)

    Sheng-Po Chang

    2012-01-01

    Full Text Available A zinc oxide (ZnO nanoparticle photodetector was fabricated using a simple method. Under a 5 V applied bias, its dark current and photocurrent were 1.98×10-8 and 9.42×10-7 A, respectively. In other words, a photocurrent-to-dark-current contrast ratio of 48 was obtained. Under incident light at a wavelength of 375 nm and a 5 V applied bias, the detector’s measured responsivity was 3.75 A/W. The transient time constants measured during the turn-ON and turn-OFF states were τON=204 s and τOFF=486 s, respectively.

  15. Zinc and cadmium monosalicylates

    Energy Technology Data Exchange (ETDEWEB)

    Kharitonov, Yu.Ya.; Tujebakhova, Z.K. (Moskovskij Khimiko-Tekhnologicheskij Inst. (USSR))

    1984-06-01

    Zinc and cadmium monosalicylates of the composition MSal, where M-Zn or Cd, Sal - twice deprotonated residue of salicylic acid O-HOC/sub 6/H/sub 4/COOH (H/sub 2/Sal), are singled out and characterized. When studying thermograms, thermogravigrams, IR absorption spectra, roentgenograms of cadmium salicylate compounds (Cd(OC/sub 6/H/sub 4/COO) and products of their thermal transformations, the processes of thermal decomposition of the compounds have been characterized. The process of cadmium monosalicylate decomposition takes place in one stage. Complete loss of salicylate acido group occurs in the range of 320-460 deg. At this decomposition stage cadmium oxide is formed. A supposition is made that cadmium complex has tetrahedral configuration, at that, each salicylate group plays the role of tetradentate-bridge ligand. The compound evidently has a polymer structure.

  16. Use of serum zinc concentration as an indicator of population zinc status.

    Science.gov (United States)

    Hess, Sonja Y; Peerson, Janet M; King, Janet C; Brown, Kenneth H

    2007-09-01

    Assessing the prevalence and severity of zinc deficiency in populations is critical to determine the need for and appropriate targeting of zinc intervention programs and to assess their effectiveness for improving the health and well-being of high-risk populations. However, there is very little information on the zinc status of populations worldwide due to the lack of consensus on appropriate biochemical indicators of zinc status. The objective of this review was to evaluate the use of serum zinc concentration as an indicator of population zinc status. We have reviewed the response of serum zinc concentration to dietary zinc restriction and zinc supplementation. In addition, we completed pooled analyses of nine zinc intervention trials in young children to assess the relations between serum zinc concentration of individuals before treatment and their responses to zinc supplementation. Also, in updated combined analyses of previously published data, we investigated the relation between the mean initial serum zinc concentration of a study population and their mean growth responses to zinc supplementation in randomized intervention trials among children. The results from depletion/repletion studies indicate that serum zinc concentrations respond appreciably to severe dietary zinc restriction, although there is considerable interindividual variation in these responses. There is also clear evidence that both individual and population mean serum zinc concentrations increase consistently during zinc supplementation, regardless of the initial level of serum zinc concentration. By contrast, an individual's serum zinc concentration does not reliably predict that person's response to zinc supplementation. Serum zinc concentration can be considered a useful biomarker of a population's risk of zinc deficiency and response to zinc interventions, although it may not be a reliable indicator of individual zinc status.

  17. Gas sensing application of nanocrystalline zinc oxide thin films prepared by spray pyrolysis

    Indian Academy of Sciences (India)

    Nisha R; K N Madhusoodanan; T V Vimalkumar; K P Vijayakumar

    2015-06-01

    Nanocrystalline oxygen-deficient ZnO thinfilm sensors were prepared by spray pyrolysis technique using zinc acetate dissolved in propanol and water as precursor. Response of the sensor to target gases NO2 and H2S is studied. At optimum temperature of 200° C, the sensors have a response of 3.32 to 7 ppm NO2 and 1.4 to 18 ppm of H2S gas. The analytical characterizations of the prepared sensors were performed using X-ray diffraction measurement, scanning electron microscopy, energy-dispersive X-ray spectroscopy and Raman spectroscopy. Dynamic response of sensors to different concentrations of NO2 and H2S gas was tested at optimum temperature. Experimental data revealed the sensors to be more selective to NO2 gas with satisfactory response and recovery time.

  18. Copper and Zinc Metallation Status of Copper Zinc Superoxide Dismutase form Amyotrophic Lateral Sclerosis Transgenic Mice

    Energy Technology Data Exchange (ETDEWEB)

    Lelie, H.L.; Miller, L.; Liba, A.; Bourassa, M.W.; Chattopadhyay, M.; Chan, P.K.; Gralla, E.B.; Borchelt, D.R.; et al

    2010-09-24

    Mutations in the metalloenzyme copper-zinc superoxide dismutase (SOD1) cause one form of familial amyotrophic lateral sclerosis (ALS), and metals are suspected to play a pivotal role in ALS pathology. To learn more about metals in ALS, we determined the metallation states of human wild-type or mutant (G37R, G93A, and H46R/H48Q) SOD1 proteins from SOD1-ALS transgenic mice spinal cords. SOD1 was gently extracted from spinal cord and separated into insoluble (aggregated) and soluble (supernatant) fractions, and then metallation states were determined by HPLC inductively coupled plasma MS. Insoluble SOD1-rich fractions were not enriched in copper and zinc. However, the soluble mutant and WT SOD1s were highly metallated except for the metal-binding-region mutant H46R/H48Q, which did not bind any copper. Due to the stability conferred by high metallation of G37R and G93A, it is unlikely that these soluble SOD1s are prone to aggregation in vivo, supporting the hypothesis that immature nascent SOD1 is the substrate for aggregation. We also investigated the effect of SOD1 overexpression and disease on metal homeostasis in spinal cord cross-sections of SOD1-ALS mice using synchrotron-based x-ray fluorescence microscopy. In each mouse genotype, except for the H46R/H48Q mouse, we found a redistribution of copper between gray and white matters correlated to areas of high SOD1. Interestingly, a disease-specific increase of zinc was observed in the white matter for all mutant SOD1 mice. Together these data provide a picture of copper and zinc in the cell as well as highlight the importance of these metals in understanding SOD1-ALS pathology.

  19. Zinc tolerance and zinc removal ability of living and dried biomass of Desmodesmus communis.

    Science.gov (United States)

    Novák, Zoltán; Jánószky, Mihály; B-Béres, Viktória; Nagy, Sándor Alex; Bácsi, István

    2014-12-01

    Effects of zinc on growth, cell morphology, oxidative stress, and zinc removal ability of the common phytoplankton species Desmodesmus communis were investigated at a concentration range of 0.25-160 mg L(-1) zinc. Cell densities and chlorophyll content decreased in treated cultures, changes in coenobia morphology and elevated lipid peroxidation levels appeared above 2.5 mg L(-1) zinc. The most effective zinc removal was observed at 5 mg L(-1) zinc concentration, while maximal amount of removed zinc appeared in 15 mg L(-1) zinc treated culture. Removed zinc is mainly bound on the cell surface. Dead biomass adsorbed more zinc than living biomass relative to unit of dry mass, but living biomass was more effective, relative to initial zinc content. This study comprehensively examines the zinc tolerance and removal ability of D. communis and demonstrates, in comparison with published literature, that these characteristics of different isolates of the same species can vary within a wide range.

  20. The five AhMTP1 zinc transporters undergo different evolutionary fates towards adaptive evolution to zinc tolerance in Arabidopsis halleri.

    Directory of Open Access Journals (Sweden)

    Zaigham Shahzad

    2010-04-01

    Full Text Available Gene duplication is a major mechanism facilitating adaptation to changing environments. From recent genomic analyses, the acquisition of zinc hypertolerance and hyperaccumulation characters discriminating Arabidopsis halleri from its zinc sensitive/non-accumulator closest relatives Arabidopsis lyrata and Arabidopsis thaliana was proposed to rely on duplication of genes controlling zinc transport or zinc tolerance. Metal Tolerance Protein 1 (MTP1 is one of these genes. It encodes a Zn(2+/H(+ antiporter involved in cytoplasmic zinc detoxification and thus in zinc tolerance. MTP1 was proposed to be triplicated in A. halleri, while it is present in single copy in A. thaliana and A. lyrata. Two of the three AhMTP1 paralogues were shown to co-segregate with zinc tolerance in a BC1 progeny from a cross between A. halleri and A. lyrata. In this work, the MTP1 family was characterized at both the genomic and functional levels in A. halleri. Five MTP1 paralogues were found to be present in A. halleri, AhMTP1-A1, -A2, -B, -C, and -D. Interestingly, one of the two newly identified AhMTP1 paralogues was not fixed at least in one A. halleri population. All MTP1s were expressed, but transcript accumulation of the paralogues co-segregating with zinc tolerance in the A. halleri X A. lyrata BC1 progeny was markedly higher than that of the other paralogues. All MTP1s displayed the ability to functionally complement a Saccharomyces cerevisiae zinc hypersensitive mutant. However, the paralogue showing the least complementation of the yeast mutant phenotype was one of the paralogues co-segregating with zinc tolerance. From our results, the hypothesis that pentaplication of MTP1 could be a major basis of the zinc tolerance character in A. halleri is strongly counter-balanced by the fact that members of the MTP1 family are likely to experience different evolutionary fates, some of which not concurring to increase zinc tolerance.

  1. Sensor technology for smart homes.

    Science.gov (United States)

    Ding, Dan; Cooper, Rory A; Pasquina, Paul F; Fici-Pasquina, Lavinia

    2011-06-01

    A smart home is a residence equipped with technology that observes the residents and provides proactive services. Most recently, it has been introduced as a potential solution to support independent living of people with disabilities and older adults, as well as to relieve the workload from family caregivers and health providers. One of the key supporting features of a smart home is its ability to monitor the activities of daily living and safety of residents, and in detecting changes in their daily routines. With the availability of inexpensive low-power sensors, radios, and embedded processors, current smart homes are typically equipped with a large amount of networked sensors which collaboratively process and make deductions from the acquired data on the state of the home as well as the activities and behaviors of its residents. This article reviews sensor technology used in smart homes with a focus on direct environment sensing and infrastructure mediated sensing. The article also points out the strengths and limitations of different sensor technologies, as well as discusses challenges and opportunities from clinical, technical, and ethical perspectives. It is recommended that sensor technologies for smart homes address actual needs of all stake holders including end users, their family members and caregivers, and their doctors and therapists. More evidence on the appropriateness, usefulness, and cost benefits analysis of sensor technologies for smart homes is necessary before these sensors should be widely deployed into real-world residential settings and successfully integrated into everyday life and health care services.

  2. Zinc toxicology following particulate inhalation

    Directory of Open Access Journals (Sweden)

    Cooper Ross

    2008-01-01

    Full Text Available The current mini-review describes the toxic effects of zinc inhalation principally in the workplace and associated complications with breathing and respiration. The International Classification of Functioning, Disability and Health Criteria were used to specifically select articles. Most of the commercial production of zinc involves the galvanizing of iron and the manufacture of brass. The recommended daily allowance for adults is 15 mg zinc/day. Metal fume fever associated with inhalation of fumes of ZnO is characterized by fatigue, chills, fever, myalgias, cough, dyspnea, leukocytosis, thirst, metallic taste and salivation. ZnCl 2 inhalation results in edema in the alveolar surface and the protein therein the lavage fluid is elevated. Particular pathological changes associated with zinc intoxication include: pale mucous membranes; jaundice; numerous Heinz bodies; and marked anemia. Adequate ambient air monitors for permissible exposure limits, excellent ventilation and extraction systems, and approved respirators are all important in providing adequate protection.

  3. Astrobiological Molecularly Imprinted Polymer Sensors

    Science.gov (United States)

    Izenberg, N. R.; Murray, G. M.; van Houten, K. A.; Hofstra, A. A.

    2005-12-01

    Development of Molecularly Imprinted Polymer (MIP) sensors for astrobiology is intended to provide a new class of microlaboratory sensors compatible with other life or biomarker detection. Molecular imprinting is a process for making selective binding sites in synthetic polymers. The process may be approached by designing the recognition site or by simply choosing monomers that may have favorable interactions with the imprinting molecule. We are working to apply this methodology to astrobiology for development of a reliable, low cost, low mass, low power consumption sensor technology for quantitative in-situ analysis of biochemistry, biomarkers, and other indicators of astrobiological importance. Specific goals of the project are: 1) To develop a general methodology and specific methods for MIP-based sensor construction. The overall methodology will guide procedures for design and testing of any desired sensor. Specific methods will be applied to key families and specific species of astrobiological interest, i.e., alkanes (and Polycyclic aromatic hydrocarbons - PAHs), amino acids, steroids, and hopanes; 2) To construct and characterize the general family and specific species sensors. We will test for accuracy, precision, interferences, and limitations of the sensor against blanks, standards, and known terrestrial biological environment samples. Additional testing will determine sturdiness and longevity of sensors after exposure to transit conditions (launch and space environment), and at potential target environments (pressure, temperature, pH, etc.); and 3) To construct and demonstrate the combination of multiple sensors into a viable prototype instrument, and roadmap the expansion of potential instrument capabilities and exploration of the ultimate environmental limitations of the technology, and the necessary changes and additions to create a mission-ready instrument. Initial work has resulted successful detection of aqueous alanine (D and L) with simple MIP

  4. Chemical sensors

    Science.gov (United States)

    Lowell, J.R. Jr.; Edlund, D.J.; Friesen, D.T.; Rayfield, G.W.

    1991-07-02

    Sensors responsive to small changes in the concentration of chemical species are disclosed. The sensors comprise a mechanochemically responsive polymeric film capable of expansion or contraction in response to a change in its chemical environment. They are operatively coupled to a transducer capable of directly converting the expansion or contraction to a measurable electrical response. 9 figures.

  5. Prevalence of Zinc Deficiency by “ Zinc Taste Test” in Pre School Children in Yazd.

    Directory of Open Access Journals (Sweden)

    Gh Maleki

    2004-10-01

    Full Text Available Introduction: Zinc deficiency is a health problem in many communities, especially among children because of growth spurt. Zinc deficiency can cause;growth limitation, delay in sexuel maturity, behavior disorders and abnormalities of immune system,susceptibility to respiratory and gasterointestinal infections and impairment of taste and smell perception. Material and Method: One of the methods of assessment the zinc defeciency is “ Zinc taste test” using zinc sulfate solution 0.1% , this test performed used to assess the zinc deficiency among preshool childeren in Yazd. The results were evaluated with measurments of weight,height and demographic data. 400 preschool children were selected by multi stage random sampling.Having good taste perception of zinc sulfate 0.1% was used as impaired taste test ( zinc deficiency and having bad taste perception as normal zinc level. Results: Regarding to zinc taste test 73.9% of study group had zinc deficiency (77.6%femal, 69.7% male There were no significant relation between zinc deficiency and measurment of weight and height,but there was higher prevalence of zinc deficiency in children who were below the 5th percentile in height and weight by age. Conclusion: 70% of preschool children in yazd had zinc deficiency assessed by “ zinc taste test”,31% of adolecents in Tehran have had zinc deficiency based on plasma , erythrocyte and hairindex. There is no significant relation between zinc deficiency and antropometric and demographic data, in this study and the study that had been done on adolescents in Tehran.Considering the prevalnce of zinc deficiency with “ Zinc taste test” ;it seems more accurate studies need to be done like zinc measurment in WBC,RBC and Platelets and zinc taste test at the same time,if correlation coefficients between zinc taste test and other tests were very strong , we can used zinc tase test in the different age for assessment of zinc body.

  6. Morphology study of electrodeposited zinc from zinc sulfate solutions as anode for zinc-air and zinc-carbon batteries

    OpenAIRE

    Nurhaswani Alias; Ahmad Azmin Mohamad

    2015-01-01

    The morphology of Zinc (Zn) deposits was investigated as anode for aqueous batteries. The Zn was deposited from zinc sulfate solution in direct current conditions on a copper surface at different current densities. The morphology characterization of Zn deposits was performed via field emission scanning electron microscopy. The Zn deposits transformed from a dense and compact structure to dendritic form with increasing current density. The electrodeposition of Zn with a current density of 0.02...

  7. Pathogen Sensors

    Directory of Open Access Journals (Sweden)

    Joseph Irudayaraj

    2009-10-01

    Full Text Available The development of sensors for detecting foodborne pathogens has been motivated by the need to produce safe foods and to provide better healthcare. However, in the more recent times, these needs have been expanded to encompass issues relating to biosecurity, detection of plant and soil pathogens, microbial communities, and the environment. The range of technologies that currently flood the sensor market encompass PCR and microarray-based methods, an assortment of optical sensors (including bioluminescence and fluorescence, in addition to biosensor-based approaches that include piezoelectric, potentiometric, amperometric, and conductometric sensors to name a few. More recently, nanosensors have come into limelight, as a more sensitive and portable alternative, with some commercial success. However, key issues affecting the sensor community is the lack of standardization of the testing protocols and portability, among other desirable elements, which include timeliness, cost-effectiveness, user-friendliness, sensitivity and specificity. [...

  8. Smart Sensors

    Science.gov (United States)

    Corsi, C.

    2007-01-01

    The term "Smart Sensors" refers to sensors which contain both sensing and signal processing capabilities with objectives ranging from simple viewing to sophisticated remote sensing, surveillance, search/track, weapon guidance, robotics, perceptronics and intelligence applications. Recently this approach is achieving higher goals by a new and revolutionary sensors concept which introduced inside the sensor some of the basic functions of living eyes, such as dynamic stare, non-uniformity compensation, spatial and temporal filtering. New objectives and requirements are presented for this type of new infrared smart sensor systems. This paper is concerned with the front end of FPA microbolometers processing, namely, the enhancement of target-to-noise ratio by background clutter suppression and the improvement in target detection by "smart" and pattern correlation thresholding.

  9. Zinc transporters and dysregulated channels in cancers

    Science.gov (United States)

    Pan, Zui; Choi, Sangyong; Ouadid-Ahidouch, Halima; Yang, Jin-Ming; Beattie, John H.; Korichneva, Irina

    2016-01-01

    As a nutritionally essential metal ion, zinc (Zn) not only constitutes a structural element for more than 3000 proteins but also plays important regulatory functions in cellular signal transduction. Zn homeostasis is tightly controlled by regulating the flux of Zn across cell membranes through specific transporters, i.e. ZnT and ZIP family proteins. Zn deficiency and malfunction of Zn transporters have been associated with many chronic diseases including cancer. However, the mechanisms underlying Zn regulatory functions in cellular signaling and their impact on the pathogenesis and progression of cancers remain largely unknown. In addition to these acknowledged multifunctions, Zn modulates a wide range of ion channels that in turn may also play an important role in cancer biology. The goal of this review is to propose how zinc deficiency, through modified Zn homeostasis, transporter activity and the putative regulatory function of Zn can influence ion channel activity, and thereby contribute to carcinogenesis and tumorigenesis. This review intends to stimulate interest in, and support for research into the understanding of Zn-modulated channels in cancers, and to search for novel biomarkers facilitating effective clinical stratification of high risk cancer patients as well as improved prevention and therapy in this emerging field. PMID:27814637

  10. [Role of zinc in type 2 diabetes].

    Science.gov (United States)

    Tamaki, Motoyuki; Fujitani, Yoshio

    2014-01-01

    Pancreatic β cells contain the highest amount of zinc among cells within the human body, and hence, the relationship between zinc and diabetes has been of great interest. To date, many studies of zinc and diabetes have been reported, including studies demonstrating that diabetic patients and mice have a decreased amount of zinc in the pancreas. Zinc may counteract the deleterious effects of oxidative stress, which contributes to reduced insulin resistance, and may also protect pancreatic β cells from glucolipotoxicity. Recently, we have shown that SLC30A8/zinc transporter 8, which is a transporter expressed on the surface of insulin granules, plays a key role in zinc transport into insulin granules and in the regulation of hepatic insulin clearance. Here, we review the role of zinc in whole-body maintenance and the latest information on the relationship between zinc and diabetes.

  11. Automotive sensors

    Science.gov (United States)

    Marek, Jiri; Illing, Matthias

    2003-01-01

    Sensors are an essential component of most electronic systems in the car. They deliver input parameters for comfort features, engine and emission control as well as for the active and passive safety systems. New technologies such as silicon micromachining play an important role for the introduction of these sensors in all vehicle classes. The importance and use of these sensor technologies in today"s automotive applications will be shown in this article. Finally an outlook on important current developments and new functions in the car will be given.

  12. Piezoceramic Sensors

    CERN Document Server

    Sharapov, Valeriy

    2011-01-01

    This book presents the latest and complete information about various types of piezosensors. A sensor is a converter of the measured physical size to an electric signal. Piezoelectric transducers and sensors are based on piezoelectric effects. They have proven to be versatile tools for the measurement of various processes. They are used for quality assurance, process control and for research and development in many different industries. In each area of application specific requirements to the parameters of transducers and sensors are developed. This book presents the fundamentals, technical des

  13. Vibrissa Sensor

    Science.gov (United States)

    2016-09-30

    Docket No. 300119 1 of 11 VIBRISSA SENSOR STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured and used by...REFERENCE TO OTHER PATENT APPLICATIONS [0002] None. BACKGROUND OF THE INVENTION (1) Field of the Invention [0003] The present invention provides a... measured as strain. [0009] Thus, there is a need for a sensor utilizing a vibrissa that can detect dynamic and high frequency movement of the

  14. Influence of DNA-methylation on zinc homeostasis in myeloid cells: Regulation of zinc transporters and zinc binding proteins.

    Science.gov (United States)

    Kessels, Jana Elena; Wessels, Inga; Haase, Hajo; Rink, Lothar; Uciechowski, Peter

    2016-09-01

    The distribution of intracellular zinc, predominantly regulated through zinc transporters and zinc binding proteins, is required to support an efficient immune response. Epigenetic mechanisms such as DNA methylation are involved in the expression of these genes. In demethylation experiments using 5-Aza-2'-deoxycytidine (AZA) increased intracellular (after 24 and 48h) and total cellular zinc levels (after 48h) were observed in the myeloid cell line HL-60. To uncover the mechanisms that cause the disturbed zinc homeostasis after DNA demethylation, the expression of human zinc transporters and zinc binding proteins were investigated. Real time PCR analyses of 14 ZIP (solute-linked carrier (SLC) SLC39A; Zrt/IRT-like protein), and 9 ZnT (SLC30A) zinc transporters revealed significantly enhanced mRNA expression of the zinc importer ZIP1 after AZA treatment. Because ZIP1 protein was also enhanced after AZA treatment, ZIP1 up-regulation might be the mediator of enhanced intracellular zinc levels. The mRNA expression of ZIP14 was decreased, whereas zinc exporter ZnT3 mRNA was also significantly increased; which might be a cellular reaction to compensate elevated zinc levels. An enhanced but not significant chromatin accessibility of ZIP1 promoter region I was detected by chromatin accessibility by real-time PCR (CHART) assays after demethylation. Additionally, DNA demethylation resulted in increased mRNA accumulation of zinc binding proteins metallothionein (MT) and S100A8/S100A9 after 48h. MT mRNA was significantly enhanced after 24h of AZA treatment also suggesting a reaction of the cell to restore zinc homeostasis. These data indicate that DNA methylation is an important epigenetic mechanism affecting zinc binding proteins and transporters, and, therefore, regulating zinc homeostasis in myeloid cells.

  15. Vibration sensors

    Science.gov (United States)

    Gupta, Amita; Singh, Ranvir; Ahmad, Amir; Kumar, Mahesh

    2003-10-01

    Today, vibration sensors with low and medium sensitivities are in great demand. Their applications include robotics, navigation, machine vibration monitoring, isolation of precision equipment & activation of safety systems e.g. airbags in automobiles. Vibration sensors have been developed at SSPL, using silicon micromachining to sense vibrations in a system in the 30 - 200 Hz frequency band. The sensing element in the silicon vibration sensor is a seismic mass suspended by thin silicon hinges mounted on a metallized glass plate forming a parallel plate capacitor. The movement of the seismic mass along the vertical axis is monitored to sense vibrations. This is obtained by measuring the change in capacitance. The movable plate of the parallel plate capacitor is formed by a block connected to a surrounding frame by four cantilever beams located on sides or corners of the seismic mass. This element is fabricated by silicon micromachining. Several sensors in the chip sizes 1.6 cm x 1.6 cm, 1 cm x 1 cm and 0.7 cm x 0.7 cm have been fabricated. Work done on these sensors, techniques used in processing and silicon to glass bonding are presented in the paper. Performance evaluation of these sensors is also discussed.

  16. Solution structure of an archaeal DNA binding protein with an eukaryotic zinc finger fold.

    Directory of Open Access Journals (Sweden)

    Florence Guillière

    Full Text Available While the basal transcription machinery in archaea is eukaryal-like, transcription factors in archaea and their viruses are usually related to bacterial transcription factors. Nevertheless, some of these organisms show predicted classical zinc fingers motifs of the C2H2 type, which are almost exclusively found in proteins of eukaryotes and most often associated with transcription regulators. In this work, we focused on the protein AFV1p06 from the hyperthermophilic archaeal virus AFV1. The sequence of the protein consists of the classical eukaryotic C2H2 motif with the fourth histidine coordinating zinc missing, as well as of N- and C-terminal extensions. We showed that the protein AFV1p06 binds zinc and solved its solution structure by NMR. AFV1p06 displays a zinc finger fold with a novel structure extension and disordered N- and C-termini. Structure calculations show that a glutamic acid residue that coordinates zinc replaces the fourth histidine of the C2H2 motif. Electromobility gel shift assays indicate that the protein binds to DNA with different affinities depending on the DNA sequence. AFV1p06 is the first experimentally characterised archaeal zinc finger protein with a DNA binding activity. The AFV1p06 protein family has homologues in diverse viruses of hyperthermophilic archaea. A phylogenetic analysis points out a common origin of archaeal and eukaryotic C2H2 zinc fingers.

  17. Zinc Plating Industry Drives Zinc Consumption by Power Grids, Railways and Highways

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>On the afternoon of June 30, at the Chengdu Lead and Zinc Summit, more than 150 partici-pants voted for the product they felt drives zinc consumption the most. 48% went for zinc plat-ing products, 16% voted for zinc oxide,

  18. High dose zinc supplementation induces hippocampal zinc deficiency and memory impairment with inhibition of BDNF signaling.

    Directory of Open Access Journals (Sweden)

    Yang Yang

    Full Text Available Zinc ions highly concentrate in hippocampus and play a key role in modulating spatial learning and memory. At a time when dietary fortification and supplementation of zinc have increased the zinc consuming level especially in the youth, the toxicity of zinc overdose on brain function was underestimated. In the present study, weaning ICR mice were given water supplemented with 15 ppm Zn (low dose, 60 ppm Zn (high dose or normal lab water for 3 months, the behavior and brain zinc homeostasis were tested. Mice fed high dose of zinc showed hippocampus-dependent memory impairment. Unexpectedly, zinc deficiency, but not zinc overload was observed in hippocampus, especially in the mossy fiber-CA3 pyramid synapse. The expression levels of learning and memory related receptors and synaptic proteins such as NMDA-NR2A, NR2B, AMPA-GluR1, PSD-93 and PSD-95 were significantly decreased in hippocampus, with significant loss of dendritic spines. In keeping with these findings, high dose intake of zinc resulted in decreased hippocampal BDNF level and TrkB neurotrophic signaling. At last, increasing the brain zinc level directly by brain zinc injection induced BDNF expression, which was reversed by zinc chelating in vivo. These results indicate that zinc plays an important role in hippocampus-dependent learning and memory and BDNF expression, high dose supplementation of zinc induces specific zinc deficiency in hippocampus, which further impair learning and memory due to decreased availability of synaptic zinc and BDNF deficit.

  19. High dose zinc supplementation induces hippocampal zinc deficiency and memory impairment with inhibition of BDNF signaling.

    Science.gov (United States)

    Yang, Yang; Jing, Xiao-Peng; Zhang, Shou-Peng; Gu, Run-Xia; Tang, Fang-Xu; Wang, Xiu-Lian; Xiong, Yan; Qiu, Mei; Sun, Xu-Ying; Ke, Dan; Wang, Jian-Zhi; Liu, Rong

    2013-01-01

    Zinc ions highly concentrate in hippocampus and play a key role in modulating spatial learning and memory. At a time when dietary fortification and supplementation of zinc have increased the zinc consuming level especially in the youth, the toxicity of zinc overdose on brain function was underestimated. In the present study, weaning ICR mice were given water supplemented with 15 ppm Zn (low dose), 60 ppm Zn (high dose) or normal lab water for 3 months, the behavior and brain zinc homeostasis were tested. Mice fed high dose of zinc showed hippocampus-dependent memory impairment. Unexpectedly, zinc deficiency, but not zinc overload was observed in hippocampus, especially in the mossy fiber-CA3 pyramid synapse. The expression levels of learning and memory related receptors and synaptic proteins such as NMDA-NR2A, NR2B, AMPA-GluR1, PSD-93 and PSD-95 were significantly decreased in hippocampus, with significant loss of dendritic spines. In keeping with these findings, high dose intake of zinc resulted in decreased hippocampal BDNF level and TrkB neurotrophic signaling. At last, increasing the brain zinc level directly by brain zinc injection induced BDNF expression, which was reversed by zinc chelating in vivo. These results indicate that zinc plays an important role in hippocampus-dependent learning and memory and BDNF expression, high dose supplementation of zinc induces specific zinc deficiency in hippocampus, which further impair learning and memory due to decreased availability of synaptic zinc and BDNF deficit.

  20. Seeking for Non-Zinc-Binding MMP-2 Inhibitors: Synthesis, Biological Evaluation and Molecular Modelling Studies

    Science.gov (United States)

    Ammazzalorso, Alessandra; De Filippis, Barbara; Campestre, Cristina; Laghezza, Antonio; Marrone, Alessandro; Amoroso, Rosa; Tortorella, Paolo; Agamennone, Mariangela

    2016-01-01

    Matrix metalloproteinases (MMPs) are an important family of zinc-containing enzymes with a central role in many physiological and pathological processes. Although several MMP inhibitors have been synthesized over the years, none reached the market because of off-target effects, due to the presence of a zinc binding group in the inhibitor structure. To overcome this problem non-zinc-binding inhibitors (NZIs) have been recently designed. In a previous article, a virtual screening campaign identified some hydroxynaphtyridine and hydroxyquinoline as MMP-2 non-zinc-binding inhibitors. In the present work, simplified analogues of previously-identified hits have been synthesized and tested in enzyme inhibition assays. Docking and molecular dynamics studies were carried out to rationalize the activity data. PMID:27782083

  1. Seeking for Non-Zinc-Binding MMP-2 Inhibitors: Synthesis, Biological Evaluation and Molecular Modelling Studies

    Directory of Open Access Journals (Sweden)

    Alessandra Ammazzalorso

    2016-10-01

    Full Text Available Matrix metalloproteinases (MMPs are an important family of zinc-containing enzymes with a central role in many physiological and pathological processes. Although several MMP inhibitors have been synthesized over the years, none reached the market because of off-target effects, due to the presence of a zinc binding group in the inhibitor structure. To overcome this problem non-zinc-binding inhibitors (NZIs have been recently designed. In a previous article, a virtual screening campaign identified some hydroxynaphtyridine and hydroxyquinoline as MMP-2 non-zinc-binding inhibitors. In the present work, simplified analogues of previously-identified hits have been synthesized and tested in enzyme inhibition assays. Docking and molecular dynamics studies were carried out to rationalize the activity data.

  2. Sensor management for multiple target tracking with heterogeneous sensor models

    Science.gov (United States)

    Williams, Jason L.; Fisher, John W., III; Willsky, Alan S.

    2006-05-01

    Modern sensors are able to rapidly change mode of operation and steer between physically separated objects. While control of such sensors over a rolling planning horizon can be formulated as a dynamic program, the optimal solution is inevitably intractable. In this paper, we consider the control problem under a restricted family of policies and show that the essential sensor control trade-offs are still captured. The advantage of this approach is that one can obtain the optimal policy within the restricted class in a tractable fashion, in this case by using the auction algorithm. The approach is well-suited for problems in which a single sensor (or group of sensors) is being used to track many targets using a heterogeneous sensor model, i.e., where the quality of observations varies with object state, such as due to obscuration. Our algorithm efficiently weighs the rewards achievable by observing each target at each time to find the best sensor plan within the restricted set. We extend this approach using a roll-out algorithm, to handle additional cases such as when observations take different amounts of time to complete.

  3. MEMS sensor technology

    Institute of Scientific and Technical Information of China (English)

    Jiang Zhuangde

    2012-01-01

    Since 1992 the author has led research group in Xi'an Jiaotong University to investigate and develop microelectro mechanical systems (MEMS) sensors, including pressure sensor, acceleration sensor, gas sensor, viscosity & density sensor, polymerase chain reaction (PCR) chip and integrated sensor etc. This paper introduces the technologies and research results related to MEMS sensors we achieved in the last 20 years.

  4. Zinc supplementation in children with cystic fibrosis

    Science.gov (United States)

    Cystic fibrosis (CF) leads to malabsorption of macro- and micronutrients. Symptomatic zinc deficiency has been reported in CF but little is known about zinc homeostasis in children with CF. Zinc supplementation (Zn suppl) is increasingly common in children with CF but it is not without theoretcial r...

  5. 21 CFR 558.78 - Bacitracin zinc.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Bacitracin zinc. 558.78 Section 558.78 Food and... in Animal Feeds § 558.78 Bacitracin zinc. (a) Specifications. Type A medicated articles containing bacitracin zinc equivalent to 10, 25, 40, or 50 grams per pound bacitracin. (b) Approvals. See No. 046573...

  6. 21 CFR 582.5991 - Zinc oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Zinc oxide. 582.5991 Section 582.5991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5991 Zinc oxide. (a) Product. Zinc oxide. (b) Conditions of use. This substance is...

  7. 21 CFR 182.8991 - Zinc oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Zinc oxide. 182.8991 Section 182.8991 Food and... CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8991 Zinc oxide. (a) Product. Zinc oxide. (b) Conditions of use. This substance is generally recognized as safe when used...

  8. 21 CFR 73.2991 - Zinc oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Zinc oxide. 73.2991 Section 73.2991 Food and Drugs... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2991 Zinc oxide. (a) Identity and specifications. The color additive zinc oxide shall conform in identity and specifications to the requirements of §...

  9. Zinc metalloproteins as medicinal targets.

    Science.gov (United States)

    Anzellotti, A I; Farrell, N P

    2008-08-01

    Zinc bioinorganic chemistry has emphasized the role of the metal ion on the structure and function of the protein. There is, more recently, an increasing appreciation of the role of zinc proteins in a variety of human diseases. This critical review, aimed at both bioinorganic and medicinal chemists, shows how apparently widely-diverging diseases share the common mechanistic approaches of targeting the essential function of the metal ion to inhibit activity. Protein structure and function is briefly summarized in the context of its clinical relevance. The status of current and potential inhibitors is discussed along with the prospects for future developments (162 references).

  10. Radial growth of zinc oxide nanowire for piezoelectric nanogenerator application

    Science.gov (United States)

    Rasouli, Safa

    2017-04-01

    Nano- and micro-self-biased sensors employed environmental harvested energy, which are provided by different methods, such as piezoelectric. Piezoelectric materials are capable of producing electrical energy from environmental mechanical force. In this paper, a radial layer of well-arrayed hexagonal zinc oxide nanowires is grown on carbon fiber substrate using a two-step Chemical deposition method of metal salt growth. The resulted morphology is examined using Field Emission Scanning Electron Microscopy (FESEM) micrographs and X-ray Diffraction (XRD) pattern which indicates the quality and the crystallization order of the samples. In addition, composition of the material is studied using a Fourier Transform Infrared (FTIR) spectroscopy method. The results show that zinc oxide nanowires are well managed in vertical direction on the cylindrical carbon fibers. The hexagonal nanowires are grown with a length from 206 to 286 nm (Nanometer) and the diameter from 75 to 103 nm. The results of FTIR spectroscopy and XRD also illustrate the wurtzite structure of zinc oxide. The synthesized nanowires are then applied in a flexible capacitive piezoelectric nanogenerator consisting of a thin Ag layer as the upper contact and a carbon substrate as the back contact which are separated by a PMMA dielectric film. The output current and voltage are measured by applying a random pulse mechanical force on the upper contact. A maximum voltage and current of 14 mV (millivolt) and 20 nA (nanoampere) are generated at the output of nanogenerator, respectively.

  11. Effect of resveratrol and zinc on intracellular zinc status in normal human prostate epithelial cells

    Science.gov (United States)

    To evaluate the influence of resveratrol on cellular zinc status, normal human prostate epithelial (NHPrE) cells were treated with 6 levels of resveratrol (0, 0.5, 1, 2.5, 5 and 10 microM) and 4 levels of zinc [0, 4, 16, and 32 microM for zinc-deficient (ZD), zinc-normal (ZN), zinc-adequate (ZA), an...

  12. Wireless Sensor Networks: Opportunities and Challenges

    Directory of Open Access Journals (Sweden)

    Matthew N. O. Sadiku

    2014-01-01

    Full Text Available The popularity of cell phones, laptops, PDAs and intelligent electronics has made computing devices to become cheaper and more pervasive in daily life. The desire for connectivity among these devices has caused an exponential growth in wireless communication. Wireless sensor networks (WSNs provide an example of this phenomenon. WSNs belong to the general family of sensor networks that employ distributed sensors to collect information on entities of interest. This paper provides a brief introduction to wireless sensor networks. It addresses the opportunities and challenges of WSNs

  13. Zinc dyshomeostasis during polymicrobial sepsis in mice involves zinc transporter Zip14 and can be overcome by zinc supplementation.

    Science.gov (United States)

    Wessels, Inga; Cousins, Robert J

    2015-11-01

    Integrity of the immune system is particularly dependent on the availability of zinc. Recent data suggest that zinc is involved in the development of sepsis, a life-threatening systemic inflammation with high death rates, but with limited therapeutic options. Altered cell zinc transport mechanisms could contribute to the inflammatory effects of sepsis. Zip14, a zinc importer induced by proinflammatory stimuli, could influence zinc metabolism during sepsis and serve as a target for therapy. Using cecal ligation-and-puncture (CLP) to model polymicrobial sepsis, we narrowed the function of ZIP14 to regulation of zinc homeostasis in hepatocytes, while hepatic leukocytes were mostly responsible for driving inflammation, as shown by higher expression of IL-1β, TNFα, S100A8, and matrix metalloproteinase-8. Using Zip14 knockout (KO) mice as a novel approach, we found that ablation of Zip14 produced a delay in development of leukocytosis, prevented zinc accumulation in the liver, altered the kinetics of hypozincemia, and drastically increased serum IL-6, TNFα, and IL-10 concentrations following CLP. Hence, this model revealed that the zinc transporter ZIP14 is a component of the pathway for zinc redistribution that contributes to zinc dyshomeostasis during polymicrobial sepsis. In contrast, using the identical CLP model, we found that supplemental dietary zinc reduced the severity of sepsis, as shown by amelioration of cytokines, calprotectins, and blood bacterial loads. We conclude that the zinc transporter ZIP14 influences aspects of the pathophysiology of nonlethal polymicrobial murine sepsis induced by CLP through zinc delivery. The results are promising for the use of zinc and its transporters as targets for future sepsis therapy.

  14. Pharmacokinetics of zinc tannate after intratesticular injection.

    Science.gov (United States)

    Migally, N B; Fahim, M S

    1984-01-01

    Forty-eight sexually mature male rats were injected intratesticularly with either 1, 3, or 6 mg zinc tannate (Kastrin) or with saline (as control). Zinc localized only in low concentration in primary spermatocytes and could not be detected in spermatogonia, Sertoli cells, spermatids, or spermatozoa. Forty-eight hours after injection of 1 mg Kastrin, zinc was accumulated in the spermatogonia and primary spermatocytes while, after injection of 3 mg, zinc was preferentially localized in Sertoli cells and spermatids; however, zinc was observed in the spermatids and spermatozoa 48 h after injection with 6 mg, and germ cells lost their identity and were fragmented after 1 week.

  15. Non-Chromate Passivation of Zinc

    DEFF Research Database (Denmark)

    Tang, Peter Torben; Bech-Nielsen, G.

    1993-01-01

    . There is no known environmental or health risk involved using the treatments mentioned above. All components used in the baths are non toxic compared to Cr(VI). Alloy coatings such as zinc/nickel, zinc/cobalt, zinc/tin and all types of pure zinc coating (from cyanide, acidic or alkaline baths) have been treated...... minutes, in any one of the baths, at 60¢XC. Some movement of the submerged samples, or stirring with air-bubbles, should be applied, just as a thorough rinse of the zinc surface immediately before the pas-sivation is extremely important....

  16. Utilization of a spiropyran derivative in a polymeric film optode for selective fluorescent sensing of zinc ion

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Ying; SHAO; Na; YANG; Ronghua; LI; Ke'an; LIU; Feng; CHAN; Winghong; MO; Tian

    2006-01-01

    A new spiropyran derivative was synthesized and first utilized in a polymeric film-based optical sensor for zinc ion. Spiropyrans, combining the characteristics of metal binding and signal transduction, show potential function in the design of optical chemical sensors (optodes) toward metal ions. When embedded in a plasticized poly (vinyl chloride) (PVC) membrane, the newly synthesized spiropyran derivative 1 exhibits obvious fluorescence enhancement at 630 nm in the presence of zinc ion in aqueous solution. With the optimum condition described, the optode membrane responds to also exhibits high selectivity toward zinc ion over transition metal ions including Hg2+, Cd2+, Pb2+, Cu2+,Fe3+and common cationic ions presented in the physiological fluids.

  17. Dissolved families

    DEFF Research Database (Denmark)

    Christoffersen, Mogens

    The situation in the family preceding a family separation is studied here, to identify risk factors for family dissolution. Information registers covering prospective statistics about health aspects, demographic variables, family violence, self-destructive behaviour, unemployment, and the spousal...

  18. Dissolved families

    DEFF Research Database (Denmark)

    Christoffersen, Mogens

    The situation in the family preceding a family separation is studied here, to identify risk factors for family dissolution. Information registers covering prospective statistics about health aspects, demographic variables, family violence, self-destructive behaviour, unemployment, and the spousal...

  19. Family Life

    Science.gov (United States)

    ... With Family and Friends > Family Life Request Permissions Family Life Approved by the Cancer.Net Editorial Board , ... your outlook on the future. Friends and adult family members The effects of cancer on your relationships ...

  20. Zinc leaching from tire crumb rubber.

    Science.gov (United States)

    Rhodes, Emily P; Ren, Zhiyong; Mays, David C

    2012-12-04

    Because tires contain approximately 1-2% zinc by weight, zinc leaching is an environmental concern associated with civil engineering applications of tire crumb rubber. An assessment of zinc leaching data from 14 studies in the published literature indicates that increasing zinc leaching is associated with lower pH and longer leaching times, but the data display a wide range of zinc concentrations, and do not address the effect of crumb rubber size or the dynamics of zinc leaching during flow through porous crumb rubber. The present study was undertaken to investigate the effect of crumb rubber size using the synthetic precipitation leaching procedure (SPLP), the effect of exposure time using quiescent batch leaching tests, and the dynamics of zinc leaching using column tests. Results indicate that zinc leaching from tire crumb rubber increases with smaller crumb rubber and longer exposure time. Results from SPLP and quiescent batch leaching tests are interpreted with a single-parameter leaching model that predicts a constant rate of zinc leaching up to 96 h. Breakthrough curves from column tests displayed an initial pulse of elevated zinc concentration (~3 mg/L) before settling down to a steady-state value (~0.2 mg/L), and were modeled with the software package HYDRUS-1D. Washing crumb rubber reduces this initial pulse but does not change the steady-state value. No leaching experiment significantly reduced the reservoir of zinc in the crumb rubber.

  1. Optics-less Sensors for Localization of Radiation Sources

    OpenAIRE

    Caulfield, H. J.; Yaroslavsky, L. P.; Goerzen, Ch.; Umansky, S.

    2008-01-01

    A new family of radiation sensors is introduced which do not require any optics. The sensors consist of arrays of elementary sub-sensors with natural cosine-law or similar angular sensitivity supplemented with a signal processing unit that computes optimal statistical estimations of source parameters. We show, both theoretically and by computer simulation, that such sensors are capable of accurate localization and intensity estimation of a given number of radiation sources and of imaging of a...

  2. Non-Chromate Passivation of Zinc

    DEFF Research Database (Denmark)

    Tang, Peter Torben; Bech-Nielsen, G.

    1993-01-01

    . There is no known environmental or health risk involved using the treatments mentioned above. All components used in the baths are non toxic compared to Cr(VI). Alloy coatings such as zinc/nickel, zinc/cobalt, zinc/tin and all types of pure zinc coating (from cyanide, acidic or alkaline baths) have been treated...... successfully. The corrosion resistance against white rust on zinc and zinc alloys is just as good as that of yellow chromate, although the result de-pends on the corrosion test method as well as on the nature of the zinc substrate pas-sivated. The passivation procedure is simply a dip for approxi-mately 2...

  3. Zinc Therapy in Dermatology: A Review

    Directory of Open Access Journals (Sweden)

    Mrinal Gupta

    2014-01-01

    Full Text Available Zinc, both in elemental or in its salt forms, has been used as a therapeutic modality for centuries. Topical preparations like zinc oxide, calamine, or zinc pyrithione have been in use as photoprotecting, soothing agents or as active ingredient of antidandruff shampoos. Its use has expanded manifold over the years for a number of dermatological conditions including infections (leishmaniasis, warts, inflammatory dermatoses (acne vulgaris, rosacea, pigmentary disorders (melasma, and neoplasias (basal cell carcinoma. Although the role of oral zinc is well-established in human zinc deficiency syndromes including acrodermatitis enteropathica, it is only in recent years that importance of zinc as a micronutrient essential for infant growth and development has been recognized. The paper reviews various dermatological uses of zinc.

  4. Zinc-The key to preventing corrosion

    Science.gov (United States)

    Kropschot, S.J.; Doebrich, Jeff L.

    2011-01-01

    Centuries before it was identified as an element, zinc was used to make brass (an alloy of zinc and copper) and for medicinal purposes. Metallic zinc and zinc oxide were produced in India sometime between the 11th and 14th centuries and in China in the 17th century, although the discovery of pure metallic zinc is credited to the German chemist Andreas Marggraf, who isolated the element in 1746. Refined zinc metal is bluish-white when freshly cast; it is hard and brittle at most temperatures and has relatively low melting and boiling points. Zinc alloys readily with other metals and is chemically active. On exposure to air, it develops a thin gray oxide film (patina), which inhibits deeper oxidation (corrosion) of the metal. The metal's resistance to corrosion is an important characteristic in its use.

  5. FurC regulates expression of zupT for the central zinc importer ZupT of Cupriavidus metallidurans.

    Science.gov (United States)

    Schmidt, Christopher; Schwarzenberger, Claudia; Große, Cornelia; Nies, Dietrich H

    2014-10-01

    The zinc importer ZupT is required for the efficient allocation of zinc to zinc-dependent proteins in the metal-resistant bacterium Cupriavidus metallidurans but not for zinc import per se. The expression of zupT is upregulated under conditions of zinc starvation. C. metallidurans contains three members of the Fur family of regulators that qualify as candidates for the zupT regulator. The expression of a zupT-lacZ reporter gene fusion was strongly upregulated in a ΔfurC mutant but not in a ΔfurA or ΔfurB mutant. Expression of the genes for transition-metal importers (pitA, corA1, corA2, and corA3) was not changed in this pattern in all three Δfur mutants, but they were still downregulated under conditions of elevated zinc concentrations, indicating the presence of another zinc-dependent regulator. FurA was a central regulator of the iron metabolism in C. metallidurans, and furA was constitutively expressed under the conditions tested. Expression of furB was upregulated under conditions of iron starvation, and FurB could be an iron starvation Fur connecting general metal and iron homeostasis, as indicated by the phenotype of a ΔfurB ΔfurC double mutant. FurC was purified as a Strep-tagged protein and retarded the electrophoretic mobility of a DNA fragment upstream of zupT. Binding of FurC to this operator region was influenced by the presence of zinc ions and EDTA. Thus, FurC is the main zinc uptake regulator (Zur) of C. metallidurans and represses synthesis of the central zinc importer ZupT when sufficient zinc is present.

  6. Recovery of zinc from low-grade zinc oxide ores by solvent extraction

    Institute of Scientific and Technical Information of China (English)

    覃文庆; 蓝卓越; 黎维中

    2003-01-01

    The recovery of zinc from low-grade zinc oxide ores with solvent extraction-electrowinning technique was investigated by using D2EHPA as extractant and 260# kerosene as diluent. The results show that it is possible to selectively leach zinc from the ores by heap leaching. The zinc concentration of leach solution in the first leaching cycle is 32.57 g/L, and in the sixteenth cycle the zinc concentration is 8.27g/L after solvent extraction. The leaching solution is subjected to solvent extraction, scrubbing and selective stripping for enrichment of zinc and removal of impurities. The pregnant zinc sulfate solution produced from the stripping cycle is suitable for zinc electrowinning.Extra-pure zinc metal was obtained in the electrowinning test under conventional conditions.

  7. Association between Maternal Zinc Status, Dietary Zinc Intake and Pregnancy Complications: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Rebecca L. Wilson

    2016-10-01

    Full Text Available Adequate zinc stores in the body are extremely important during periods of accelerated growth. However, zinc deficiency is common in developing countries and low maternal circulating zinc concentrations have previously been associated with pregnancy complications. We reviewed current literature assessing circulating zinc and dietary zinc intake during pregnancy and the associations with preeclampsia (PE; spontaneous preterm birth (sPTB; low birthweight (LBW; and gestational diabetes (GDM. Searches of MEDLINE; CINAHL and Scopus databases identified 639 articles and 64 studies were reviewed. In 10 out of 16 studies a difference was reported with respect to circulating zinc between women who gave birth to a LBW infant (≤2500 g and those who gave birth to an infant of adequate weight (>2500 g, particularly in populations where inadequate zinc intake is prevalent. In 16 of our 33 studies an association was found between hypertensive disorders of pregnancy and circulating zinc; particularly in women with severe PE (blood pressure ≥160/110 mmHg. No association between maternal zinc status and sPTB or GDM was seen; however; direct comparisons between the studies was difficult. Furthermore; only a small number of studies were based on women from populations where there is a high risk of zinc deficiency. Therefore; the link between maternal zinc status and pregnancy success in these populations cannot be established. Future studies should focus on those vulnerable to zinc deficiency and include dietary zinc intake as a measure of zinc status.

  8. Association between Maternal Zinc Status, Dietary Zinc Intake and Pregnancy Complications: A Systematic Review

    Science.gov (United States)

    Wilson, Rebecca L.; Grieger, Jessica A.; Bianco-Miotto, Tina; Roberts, Claire T.

    2016-01-01

    Adequate zinc stores in the body are extremely important during periods of accelerated growth. However, zinc deficiency is common in developing countries and low maternal circulating zinc concentrations have previously been associated with pregnancy complications. We reviewed current literature assessing circulating zinc and dietary zinc intake during pregnancy and the associations with preeclampsia (PE); spontaneous preterm birth (sPTB); low birthweight (LBW); and gestational diabetes (GDM). Searches of MEDLINE; CINAHL and Scopus databases identified 639 articles and 64 studies were reviewed. In 10 out of 16 studies a difference was reported with respect to circulating zinc between women who gave birth to a LBW infant (≤2500 g) and those who gave birth to an infant of adequate weight (>2500 g), particularly in populations where inadequate zinc intake is prevalent. In 16 of our 33 studies an association was found between hypertensive disorders of pregnancy and circulating zinc; particularly in women with severe PE (blood pressure ≥160/110 mmHg). No association between maternal zinc status and sPTB or GDM was seen; however; direct comparisons between the studies was difficult. Furthermore; only a small number of studies were based on women from populations where there is a high risk of zinc deficiency. Therefore; the link between maternal zinc status and pregnancy success in these populations cannot be established. Future studies should focus on those vulnerable to zinc deficiency and include dietary zinc intake as a measure of zinc status. PMID:27754451

  9. Load sensor

    NARCIS (Netherlands)

    Van den Ende, D.; Almeida, P.M.R.; Dingemans, T.J.; Van der Zwaag, S.

    2007-01-01

    The invention relates to a load sensor comprising a polymer matrix and a piezo-ceramic material such as PZT, em not bedded in the polymer matrix, which together form a compos not ite, wherein the polymer matrix is a liquid crystalline resin, and wherein the piezo-ceramic material is a PZT powder for

  10. Gas sensor

    Science.gov (United States)

    Schmid, Andreas K.; Mascaraque, Arantzazu; Santos, Benito; de la Figuera, Juan

    2014-09-09

    A gas sensor is described which incorporates a sensor stack comprising a first film layer of a ferromagnetic material, a spacer layer, and a second film layer of the ferromagnetic material. The first film layer is fabricated so that it exhibits a dependence of its magnetic anisotropy direction on the presence of a gas, That is, the orientation of the easy axis of magnetization will flip from out-of-plane to in-plane when the gas to be detected is present in sufficient concentration. By monitoring the change in resistance of the sensor stack when the orientation of the first layer's magnetization changes, and correlating that change with temperature one can determine both the identity and relative concentration of the detected gas. In one embodiment the stack sensor comprises a top ferromagnetic layer two mono layers thick of cobalt deposited upon a spacer layer of ruthenium, which in turn has a second layer of cobalt disposed on its other side, this second cobalt layer in contact with a programmable heater chip.

  11. The biological inorganic chemistry of zinc ions.

    Science.gov (United States)

    Krężel, Artur; Maret, Wolfgang

    2016-12-01

    The solution and complexation chemistry of zinc ions is the basis for zinc biology. In living organisms, zinc is redox-inert and has only one valence state: Zn(II). Its coordination environment in proteins is limited by oxygen, nitrogen, and sulfur donors from the side chains of a few amino acids. In an estimated 10% of all human proteins, zinc has a catalytic or structural function and remains bound during the lifetime of the protein. However, in other proteins zinc ions bind reversibly with dissociation and association rates commensurate with the requirements in regulation, transport, transfer, sensing, signalling, and storage. In contrast to the extensive knowledge about zinc proteins, the coordination chemistry of the "mobile" zinc ions in these processes, i.e. when not bound to proteins, is virtually unexplored and the mechanisms of ligand exchange are poorly understood. Knowledge of the biological inorganic chemistry of zinc ions is essential for understanding its cellular biology and for designing complexes that deliver zinc to proteins and chelating agents that remove zinc from proteins, for detecting zinc ion species by qualitative and quantitative analysis, and for proper planning and execution of experiments involving zinc ions and nanoparticles such as zinc oxide (ZnO). In most investigations, reference is made to zinc or Zn(2+) without full appreciation of how biological zinc ions are buffered and how the d-block cation Zn(2+) differs from s-block cations such as Ca(2+) with regard to significantly higher affinity for ligands, preference for the donor atoms of ligands, and coordination dynamics. Zinc needs to be tightly controlled. The interaction with low molecular weight ligands such as water and inorganic and organic anions is highly relevant to its biology but in contrast to its coordination in proteins has not been discussed in the biochemical literature. From the discussion in this article, it is becoming evident that zinc ion speciation is

  12. Influence of phytase, EDTA, and polyphenols on zinc absorption in adults from porridges fortified with zinc sulfate or zinc oxide.

    Science.gov (United States)

    Brnić, Marica; Wegmüller, Rita; Zeder, Christophe; Senti, Gabriela; Hurrell, Richard F

    2014-09-01

    Fortification of cereal staples with zinc is recommended to combat zinc deficiency. To optimize zinc absorption, strategies are needed to overcome the inhibitory effect of phytic acid (PA) and perhaps polyphenols. Five zinc absorption studies were conducted in young adults consuming maize or sorghum porridges fortified with 2 mg zinc as zinc sulfate (ZnSO4) or zinc oxide (ZnO) and containing combinations of PA or polyphenols as potential inhibitors and EDTA and phytase as potential enhancers. Fractional absorption of zinc (FAZ) was measured by using the double isotopic tracer ratio method. Adding phytase to the maize porridge immediately before consumption or using phytase for dephytinization during meal preparation both increased FAZ by >80% (both P zinc molar ratio of 1:1 increased FAZ from maize porridge fortified with ZnSO4 by 30% (P = 0.01) but had no influence at higher EDTA ratios or on absorption from ZnO. FAZ was slightly higher from ZnSO4 than from ZnO (P = 0.02). Sorghum polyphenols had no effect on FAZ from dephytinized sorghum porridges but decreased FAZ by 20% from PA-rich sorghum porridges (P zinc absorption from zinc-fortified cereals, EDTA at a 1:1 molar ratio modestly enhanced zinc absorption from ZnSO4-fortified cereals but not ZnO-fortified cereals, and sorghum polyphenols inhibited zinc absorption in the presence, but not absence, of PA. This trial was registered at clinicaltrials.gov as NCT01210794.

  13. El zinc: oligoelemento esencial Zinc: an essential oligoelement

    Directory of Open Access Journals (Sweden)

    C. Rubio

    2007-02-01

    Full Text Available En este artículo se hace una revisión exhaustiva del zinc, elemento metálico esencial para el funcionamiento del organismo. Repasamos y reflejamos aspectos relacionados con la farmacocinética, con las fuentes dietéticas más importantes, así como las IDR (Ingestas Dietéticas Recomendadas del mismo. También se hace mención a los signos y síntomas relacionados tanto con una ingesta deficiente, como con posibles efectos tóxicos, derivados de ingestas excesivas.This article comprehensively reviews zinc, the metallic element essential for body functioning. We review and highlight issues related to pharmacokinetics, the most important dietary sources, as well as its RDIs (Recommended Dietary Intakes. We also focus on signs and symptoms related with both a deficient intake and possible toxic effects derived from excessive intakes.

  14. Highly sensitive fiber grating chemical sensors: An effective alternative to atomic absorption spectroscopy

    Science.gov (United States)

    Laxmeshwar, Lata. S.; Jadhav, Mangesh S.; Akki, Jyoti. F.; Raikar, Prasad; Kumar, Jitendra; prakash, Om; Raikar, U. S.

    2017-06-01

    Accuracy in quantitative determination of trace elements like Zinc, present in drinking water in ppm level, is a big challenge and optical fiber gratings as chemical sensors may provide a promising solution to overcome the same. This paper presents design of two simple chemical sensors based on the principle of shift in characteristic wavelength of gratings with change in their effective refractive index, to measure the concentration of Zinc in drinking water using etched short period grating (FBG) and Long period grating (LPG) respectively. Three samples of drinking water from different places have been examined for presence of Zinc. Further, the results obtained by our sensors have also been verified with the results obtained by a standard method, Atomic absorption spectroscopy (AAS). The whole experiment has been performed by fixing the fibers in a horizontal position with the sensor regions at the center of the fibers, making it less prone to disturbance and breaking. The sensitivity of LPG sensor is about 205 times that of the FBG sensor. A few advantages of Fiber grating sensors, besides their regular features, over AAS have also been discussed, that make our sensors potential alternatives for existing techniques in determination of trace elements in drinking water.

  15. From Simple to Smart: The Development of Sensor Network

    Institute of Scientific and Technical Information of China (English)

    Ping Liu; Xunxiang Huang; Feng Liu; Lianghua Zhang

    2006-01-01

    Sensor networks have come a long way since the first point-to-point analog system. Rapid development of industrial applications imposes more challenges on traditional sensors and sensor networks. And World Wide Web browsers and object-oriented programming techniques are also helping shaping the next generation of sensor networks. As a trend, smart sensor networks are getting more attention in industrial areas for the values they can bring into us. The IEEE 1451 family of smart sensor interface standards tends to resolve the issues and problems associated with the proliferation and the heterogeneity of sensor networks. The evolution and current state of the art of sensor networks is captured in this article, where the characteristics of their generations are discussed under the networking technologies. It is also pointed out that the challenges sensor networks will face and intends of this field.

  16. Zinc oxide nanorod field effect transistor for long-time cellular force measurement.

    Science.gov (United States)

    Zong, Xianli; Zhu, Rong

    2017-03-08

    Mechanical forces generated by cells are known to influence a vast range of cellular functions ranging from receptor signaling and transcription to differentiation and proliferation. We report a novel measurement approach using zinc oxide nanorods as a peeping transducer to monitor dynamic mechanical behavior of cellular traction on surrounding substrate. We develop a ZnO nanorod field effect transistor (FET) as an ultrasensitive force sensor to realize long-time, unstained, and in-situ detection of cell cycle phases, including attachment, spread, and mitosis. Excellent biocompatibility and ultra-sensitivity of the biomechanical measurement is ensured by coating a parylene film on the FET sensor as a concealment, which provides complete electronic isolation between the sensor and cell. With unique features of ultra-sensitivity, label-free, easy handling, and good biocompatibility, the force sensor allows feasible for tracking cellular dynamics in physiological contexts and understanding their contribution to biological processes.

  17. Regulation and activity of a zinc uptake regulator, Zur, in Corynebacterium diphtheriae.

    Science.gov (United States)

    Smith, Kelsy F; Bibb, Lori A; Schmitt, Michael P; Oram, Diana M

    2009-03-01

    Regulation of metal ion homeostasis is essential to bacterial cell survival, and in most species it is controlled by metal-dependent transcriptional regulators. In this study, we describe a Corynebacterium diphtheriae ferric uptake regulator-family protein, Zur, that controls expression of genes involved in zinc uptake. By measuring promoter activities and mRNA levels, we demonstrate that Zur represses transcription of three genes (zrg, cmrA, and troA) in zinc-replete conditions. All three of these genes have similarity to genes involved in zinc uptake. Transcription of zrg and cmrA was also shown to be regulated in response to iron and manganese, respectively, by mechanisms that are independent of Zur. We demonstrate that the activity of the zur promoter is slightly decreased under low zinc conditions in a process that is dependent on Zur itself. This regulation of zur transcription is distinctive and has not yet been described for any other zur. An adjacent gene, predicted to encode a metal-dependent transcriptional regulator in the ArsR/SmtB family, is transcribed from a separate promoter whose activity is unaffected by Zur. A C. diphtheriae zur mutant was more sensitive to peroxide stress, which suggests that zur has a role in protecting the bacterium from oxidative damage. Our studies provide the first evidence of a zinc specific transcriptional regulator in C. diphtheriae and give new insights into the intricate regulatory network responsible for regulating metal ion concentrations in this toxigenic human pathogen.

  18. Intracellular zinc distribution in mitochondria, ER and the Golgi apparatus.

    Science.gov (United States)

    Lu, Qiping; Haragopal, Hariprakash; Slepchenko, Kira G; Stork, Christian; Li, Yang V

    2016-01-01

    Zinc (Zn(2+)) is required for numerous cellular functions. As such, the homeostasis and distribution of intracellular zinc can influence cellular metabolism and signaling. However, the exact distribution of free zinc within live cells remains elusive. Previously we showed the release of zinc from thapsigargin/IP3-sensitive endoplasmic reticulum (ER) storage in cortical neurons. In the present study, we investigated if other cellular organelles also contain free chelatable zinc and function as organelle storage for zinc. To identify free zinc within the organelles, live cells were co-stained with Zinpyr-1, a zinc fluorescent dye, and organelle-specific fluorescent dyes (MitoFluor Red 589: mitochondria; ER Tracker Red: endoplasmic reticulum; BODIPY TR ceramide: Golgi apparatus; Syto Red 64: nucleus). We examined organelles that represent potential storing sites for intracellular zinc. We showed that zinc fluorescence staining was co-localized with MitoFluor Red 589, ER Tracker Red, and BODIPY TR ceramide respectively, suggesting the presence of free zinc in mitochondria, endoplasmic reticulum, and the Golgi apparatus. On the other hand, cytosol and nucleus had nearly no detectable zinc fluorescence. It is known that nucleus contains high amount of zinc binding proteins that have high zinc binding affinity. The absence of zinc fluorescence suggests that there is little free zinc in these two regions. It also indicates that the zinc fluorescence detected in mitochondria, ER and Golgi apparatus represents free chelatable zinc. Taken together, our results support that these organelles are potential zinc storing organelles during cellular zinc homeostasis.

  19. The Current Trend of China’s Zinc Consumption

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正> According to estimations of zinc consumptionby China’s major zinc consumption industries,the growth rate of China’s actual zinc con-sumption in the period 1998-2002 was 10.2percent.Of China’s total zinc consumption inyear 2002,galvanizing zinc made 36 percent,

  20. Pressure sensor

    Science.gov (United States)

    Mee, David K.; Ripley, Edward B.; Nienstedt, Zachary C.; Nienstedt, Alex W.; Howell, Jr., Layton N.

    2015-09-29

    Disclosed is a passive, in-situ pressure sensor. The sensor includes a sensing element having a ferromagnetic metal and a tension inducing mechanism coupled to the ferromagnetic metal. The tension inducing mechanism is operable to change a tensile stress upon the ferromagnetic metal based on a change in pressure in the sensing element. Changes in pressure are detected based on changes in the magnetic switching characteristics of the ferromagnetic metal when subjected to an alternating magnetic field caused by the change in the tensile stress. The sensing element is embeddable in a closed system for detecting pressure changes without the need for any penetrations of the system for power or data acquisition by detecting changes in the magnetic switching characteristics of the ferromagnetic metal caused by the tensile stress.

  1. Semiconductor sensors

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Frank, E-mail: frank.hartmann@cern.c [Institut fuer Experimentelle Kernphysik, KIT, Wolfgang-Gaede-Str. 1, Karlsruhe 76131 (Germany)

    2011-02-01

    Semiconductor sensors have been around since the 1950s and today, every high energy physics experiment has one in its repertoire. In Lepton as well as Hadron colliders, silicon vertex and tracking detectors led to the most amazing physics and will continue doing so in the future. This contribution tries to depict the history of these devices exemplarily without being able to honor all important developments and installations. The current understanding of radiation damage mechanisms and recent R and D topics demonstrating the future challenges and possible technical solutions for the SLHC detectors are presented. Consequently semiconductor sensor candidates for an LHC upgrade and a future linear collider are also briefly introduced. The work presented here is a collage of the work of many individual silicon experts spread over several collaborations across the world.

  2. Corrosion sensor

    Science.gov (United States)

    Glass, Robert S.; Clarke, Jr., Willis L.; Ciarlo, Dino R.

    1994-01-01

    A corrosion sensor array incorporating individual elements for measuring various elements and ions, such as chloride, sulfide, copper, hydrogen (pH), etc. and elements for evaluating the instantaneous corrosion properties of structural materials. The exact combination and number of elements measured or monitored would depend upon the environmental conditions and materials used which are subject to corrosive effects. Such a corrosion monitoring system embedded in or mounted on a structure exposed to the environment would serve as an early warning system for the onset of severe corrosion problems for the structure, thus providing a safety factor as well as economic factors. The sensor array is accessed to an electronics/computational system, which provides a means for data collection and analysis.

  3. Interactions between zinc transporter-8 gene (SLC30A8) and plasma zinc concentrations for impaired glucose regulation and type 2 diabetes.

    Science.gov (United States)

    Shan, Zhilei; Bao, Wei; Zhang, Yan; Rong, Ying; Wang, Xia; Jin, Yilin; Song, Yadong; Yao, Ping; Sun, Changhao; Hu, Frank B; Liu, Liegang

    2014-05-01

    Although both SLC30A8 rs13266634 single nucleotide polymorphism and plasma zinc concentrations have been associated with impaired glucose regulation (IGR) and type 2 diabetes (T2D), their interactions for IGR and T2D remain unclear. Therefore, to assess zinc-SLC30A8 interactions, we performed a case-control study in 1,796 participants: 218 newly diagnosed IGR patients, 785 newly diagnosed T2D patients, and 793 individuals with normal glucose tolerance. After adjustment for age, sex, BMI, family history of diabetes, and hypertension, the multivariable odds ratio (OR) of T2D associated with a 10 µg/dL higher plasma zinc level was 0.87 (95% CI 0.85-0.90). Meanwhile, the OR of SLC30A8 rs13266634 homozygous genotypes CC compared with TT was 1.53 (1.11-2.09) for T2D. Similar associations were found in IGR and IGR&T2D groups. Each 10 µg/dL increment of plasma zinc was associated with 22% (OR 0.78 [0.72-0.85]) lower odds of T2D in TT genotype carriers, 17% (0.83 [0.80-0.87]) lower odds in CT genotype carriers, and 7% (0.93 [0.90-0.97]) lower odds in CC genotype carriers (P for interaction = 0.01). Our study suggested that the C allele of rs13266634 was associated with higher odds of T2D, and higher plasma zinc was associated with lower odds. The inverse association of plasma zinc concentrations with T2D was modified by SLC30A8 rs13266634. Further studies are warranted to confirm our findings and clarify the mechanisms underlying the interaction between plasma zinc and the SLC30A8 gene in relation to T2D.

  4. Zinc Prevents the Development of Diabetic Cardiomyopathy in db/db Mice

    Directory of Open Access Journals (Sweden)

    Shudong Wang

    2017-03-01

    Full Text Available Diabetic cardiomyopathy (DCM is highly prevalent in type 2 diabetes (T2DM patients. Zinc is an important essential trace metal, whose deficiency is associated with various chronic ailments, including vascular diseases. We assessed T2DM B6.BKS(D-Leprdb/J (db/db mice fed for six months on a normal diet containing three zinc levels (deficient, adequate, and supplemented, to explore the role of zinc in DCM development and progression. Cardiac function, reflected by ejection fraction, was significantly decreased, along with increased left ventricle mass and heart weight to tibial length ratio, in db/db mice. As a molecular cardiac hypertrophy marker, atrial natriuretic peptide levels were also significantly increased. Cardiac dysfunction and hypertrophy were accompanied by significantly increased fibrotic (elevated collagen accumulation as well as transforming growth factor β and connective tissue growth factor levels and inflammatory (enhanced expression of tumor necrosis factor alpha, interleukin-1β, caspase recruitment domain family member 9, and B-cell lymphoma/leukemia 10, and activated p38 mitogen-activated protein kinase responses in the heart. All these diabetic effects were exacerbated by zinc deficiency, and not affected by zinc supplementation, respectively. Mechanistically, oxidative stress and damage, mirrored by the accumulation of 3-nitrotyrosine and 4-hydroxy-2-nonenal, was significantly increased along with significantly decreased expression of Nrf2 and its downstream antioxidants (NQO-1 and catalase. This was also exacerbated by zinc deficiency in the db/db mouse heart. These results suggested that zinc deficiency promotes the development and progression of DCM in T2DM db/db mice. The exacerbated effects by zinc deficiency on the heart of db/db mice may be related to further suppression of Nrf2 expression and function.

  5. Morphology study of electrodeposited zinc from zinc sulfate solutions as anode for zinc-air and zinc-carbon batteries

    Directory of Open Access Journals (Sweden)

    Nurhaswani Alias

    2015-01-01

    Full Text Available The morphology of Zinc (Zn deposits was investigated as anode for aqueous batteries. The Zn was deposited from zinc sulfate solution in direct current conditions on a copper surface at different current densities. The morphology characterization of Zn deposits was performed via field emission scanning electron microscopy. The Zn deposits transformed from a dense and compact structure to dendritic form with increasing current density. The electrodeposition of Zn with a current density of 0.02 A cm−2 exhibited good morphology with a high charge efficiency that reached up to 95.2%. The Zn deposits were applied as the anode in zinc–air and zinc–carbon batteries, which gave specific discharge capacities of 460 and 300 mA h g−1, respectively.

  6. Production of nano zinc, zinc sulphide and nanocomplex of magnetite zinc oxide by Brevundimonas diminuta and Pseudomonas stutzeri.

    Science.gov (United States)

    Mirhendi, Mansoureh; Emtiazi, Giti; Roghanian, Rasoul

    2013-12-01

    ZnO (Zincite) nanoparticle has many industrial applications and is mostly produced by chemical reactions, usually prepared by decomposition of zinc acetate or hot-injection and heating-up method. Synthesis of semi-conductor nanoparticles such as ZnS (Sphalerite) by ultrasonic was previously reported. In this work, high-zinc tolerant bacteria were isolated and used for nano zinc production. Among all isolated microorganisms, a gram negative bacterium which was identified as Brevundimonas diminuta could construct nano magnetite zinc oxide on bacterial surface with 22 nm in size and nano zinc with 48.29 nm in size. A piece of zinc metal was immersed in medium containing of pure culture of B. diminuta. Subsequently, a yellow-white biofilm was formed which was collected from the surface of zinc. It was dried at room temperature. The isolated biofilm was analysed by X-ray diffractometer. Interestingly, the yield of these particles was higher in the light, with pH 7 at 23°C. To the best of the authors knowledge, this is the first report about the production of nano zinc metal and nano zinc oxide that are stable and have anti-bacterial activities with magnetite property. Also ZnS (sized 12 nm) produced by Pseudomonas stutzeri, was studied by photoluminescence and fluorescent microscope.

  7. Micro Ethanol Sensors with a Heater Fabricated Using the Commercial 0.18 μm CMOS Process

    Directory of Open Access Journals (Sweden)

    Wei-Zhen Liao

    2013-09-01

    Full Text Available The study investigates the fabrication and characterization of an ethanol microsensor equipped with a heater. The ethanol sensor is manufactured using the commercial 0.18 µm complementary metal oxide semiconductor (CMOS process. The sensor consists of a sensitive film, a heater and interdigitated electrodes. The sensitive film is zinc oxide prepared by the sol-gel method, and it is coated on the interdigitated electrodes. The heater is located under the interdigitated electrodes, and it is used to supply a working temperature to the sensitive film. The sensor needs a post-processing step to remove the sacrificial oxide layer, and to coat zinc oxide on the interdigitated electrodes. When the sensitive film senses ethanol gas, the resistance of the sensor generates a change. An inverting amplifier circuit is utilized to convert the resistance variation of the sensor into the output voltage. Experiments show that the sensitivity of the ethanol sensor is 0.35 mV/ppm.

  8. Recovery of Zinc from Zinc Ash and Flue Dusts by Hydrometallurgical Processing

    Science.gov (United States)

    Thorsen, G.; Grislingås, A.; Steintveit, G.

    1981-01-01

    A process has been developed for recovering zinc and other metal values from chloride-containing solid zinc waste materials such as zinc ash from galvanizing baths, and flue dusts from zinc smelting and Waelz processes. The waste is leached with a liquid organic phase containing a cation exchanger; the commercial carboxylic acid Versatic 911 is highly efficient for this operation. Halogens present in the organic phase are readily washed out with water. Zinc and other metal values are then selectively stripped with sulfuric acid, generating a neutral solution of zinc sulfate suitable for electrolytic production of zinc metal. Alternatively, zinc sulfate can be crystallized directly from the organic phase by stripping with concentrated sulfuric acid.

  9. The zinc electrode - Its behaviour in the nickel oxide-zinc accumulator

    Science.gov (United States)

    Certain aspects of zinc electrode reaction and behavior are investigated in view of their application to batteries. The properties of the zinc electrode in a battery system are discussed, emphasizing porous structure. Shape change is emphasized as the most important factor leading to limited battery cycle life. It is shown that two existing models of shape change based on electroosmosis and current distribution are unable to consistently describe observed phenomena. The first stages of electrocrystallization are studied and the surface reactions between the silver substrate and the deposited zinc layer are investigated. The reaction mechanism of zinc and amalgamated zinc in an alkaline electrolyte is addressed, and the batter system is studied to obtain information on cycling behavior and on the shape change phenomenon. The effect on cycle behavior of diferent amalgamation techniques of the zinc electrode and several additives is addressed. Impedance measurements on zinc electrodes are considered, and battery behavior is correlated with changes in the zinc electrode during cycling.

  10. Development of zinc oxide nanoparticle by sonochemical method and study of their physical and optical properties

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Samreen Heena, E-mail: samreen.heena.khan@gmail.com; Suriyaprabha, R. [Centre for Nanosciences, Central University of Gujarat, Gandhinagar, India- 382030 (India); Pathak, Bhawana, E-mail: bhawana.pathak@cug.ac.in; Fulekar, M. H., E-mail: mhfulekar@yahoo.com [School of Environment and Sustainable Development, Central University of Gujarat, Gandhinagar, India- 382030 (India)

    2016-04-13

    With the miniaturization of crystal size, the fraction of under-coordinated surface atoms becomes dominant, and hence, materials in the nano-regime behave very differently from the similar material in a bulk. Zinc oxide (ZnO), particularly, exhibits extraordinary properties such as a wide direct band gap (3.37 eV), large excitation binding energy (60 meV), low refractive index (1.9), stability to intense ultraviolet (UV) illumination, resistance to high-energy irradiation, and lower toxicity as compared to other semiconductors. This very property makes Zinc Oxide a potential candidate in many application fields, particularly as a prominent semiconductor. Zinc Oxide plays a significant role in many technological advances with its application in semiconductor mediated photocatalytic processes and sensor, solar cells and others. In present study, Zinc Oxide (ZnO) has been synthesized using three different precursors by sonochemical method. Zinc Acetate Dihydrate, Zinc Nitrate Hexahydrate and Zinc Sulphate Heptahydrate used as a precursor for the synthesis process. The synthesized ZnO nanoparticle has been found under the range of ∼50 nm. Zinc oxide nanoparticles were characterized using different characterizing tools. The as-synthesized ZnO was characterized by Fourier Transform-Infrared Spectroscopy (FT-IR) for the determination of functional group; Scanning Electron Microscopy equipped with Energy Dispersive Spectroscopy (SEM-EDS) for Morphology and elemental detection respectively, Transmission Electron Microscopy for Particle size distribution and morphology and X-Ray Diffraction (XRD) for the confirmation of crystal structure of the nanomaterial. The optical properties of the ZnO were examined by UV-VIS spectroscopy equipped with Diffuse Reflectance spectroscopy (DRS) confirmed the optical band gap of ZnO-3 around 3.23 eV resembles with the band gap of bulk ZnO (3.37eV). The TEM micrograph of the as-synthesized material showed perfectly spherical shaped

  11. Development of zinc oxide nanoparticle by sonochemical method and study of their physical and optical properties

    Science.gov (United States)

    Khan, Samreen Heena; Suriyaprabha, R.; Pathak, Bhawana; Fulekar, M. H.

    2016-04-01

    With the miniaturization of crystal size, the fraction of under-coordinated surface atoms becomes dominant, and hence, materials in the nano-regime behave very differently from the similar material in a bulk. Zinc oxide (ZnO), particularly, exhibits extraordinary properties such as a wide direct band gap (3.37 eV), large excitation binding energy (60 meV), low refractive index (1.9), stability to intense ultraviolet (UV) illumination, resistance to high-energy irradiation, and lower toxicity as compared to other semiconductors. This very property makes Zinc Oxide a potential candidate in many application fields, particularly as a prominent semiconductor. Zinc Oxide plays a significant role in many technological advances with its application in semiconductor mediated photocatalytic processes and sensor, solar cells and others. In present study, Zinc Oxide (ZnO) has been synthesized using three different precursors by sonochemical method. Zinc Acetate Dihydrate, Zinc Nitrate Hexahydrate and Zinc Sulphate Heptahydrate used as a precursor for the synthesis process. The synthesized ZnO nanoparticle has been found under the range of ˜50 nm. Zinc oxide nanoparticles were characterized using different characterizing tools. The as-synthesized ZnO was characterized by Fourier Transform-Infrared Spectroscopy (FT-IR) for the determination of functional group; Scanning Electron Microscopy equipped with Energy Dispersive Spectroscopy (SEM-EDS) for Morphology and elemental detection respectively, Transmission Electron Microscopy for Particle size distribution and morphology and X-Ray Diffraction (XRD) for the confirmation of crystal structure of the nanomaterial. The optical properties of the ZnO were examined by UV-VIS spectroscopy equipped with Diffuse Reflectance spectroscopy (DRS) confirmed the optical band gap of ZnO-3 around 3.23 eV resembles with the band gap of bulk ZnO (3.37eV). The TEM micrograph of the as-synthesized material showed perfectly spherical shaped

  12. High performance zinc anode for battery applications

    Science.gov (United States)

    Casey, John E., Jr. (Inventor)

    1998-01-01

    An improved zinc anode for use in a high density rechargeable alkaline battery is disclosed. A process for making the zinc electrode comprises electrolytic loading of the zinc active material from a slightly acidic zinc nitrate solution into a substrate of nickel, copper or silver. The substrate comprises a sintered plaque having very fine pores, a high surface area, and 80-85 percent total initial porosity. The residual porosity after zinc loading is approximately 25-30%. The electrode of the present invention exhibits reduced zinc mobility, shape change and distortion, and demonstrates reduced dendrite buildup cycling of the battery. The disclosed battery is useful for applications requiring high energy density and multiple charge capability.

  13. The role of zinc in acute pyelonephritis.

    Science.gov (United States)

    Mahyar, Abolfazl; Ayazi, Parviz; Farzadmanesh, Shahin; Sahmani, Mehdi; Oveisi, Sonia; Chegini, Victoria; Esmaeily, Shiva

    2015-09-01

    This study was conducted to determine the serum concentration of zinc in children with acute pyelonephritis. Serum zinc levels of 60 children with acute pyelonephritis and 60 healthy children were compared. Acute pyelonephritis was diagnosed using Tc-99m dimercaptosuccinic acid (DMSA) renal scan. Serum zinc levels were measured by the atomic absorption flame spectrophotometry. The levels in question in the case and control groups were 70.73 ± 14.15 and 87.61 ± 12.68 mcg/dL, respectively (P=0.001). There was no correlation between serum zinc level with inflammatory markers, severity of acute pyelonephritis and duration of the disease. This study showed that there is a correlation between serum zinc level and acute pyelonephritis. Zinc would therefore appear to play a certain role in the pathogenesis of acute pyelonephritis.

  14. Thermal flow micro sensors

    OpenAIRE

    Elwenspoek, M.

    1999-01-01

    A review is given on sensors fabricated by silicon micromachining technology using the thermal domain for the measurement of fluid flow. Attention is paid especially to performance and geometry of the sensors. Three basic types of thermal flow sensors are discussed: anemometers, calorimetric flow sensors and time of flight flow sensors. Anemometers may comprise several heaters and temperature sensors and from a geometric point of view are similar sometimes for calorimetric flow sensors. We fi...

  15. Zinc therapy for different causes of diarrhea

    OpenAIRE

    Hafaz Zakky Abdillah; Supriatmo Supriatmo; Melda Deliana; Selvi Nafianti; Atan Baas Sinuhaji

    2013-01-01

    Background The incidence of diarrhea in Indonesia has declined in the past five years. In spite of the increasing number of studies on the treatment for acute diarrhea, especially the use of zinc, it is not known if bacterial vs. non-bacterial etiology makes a difference in the reduction of severity of acute diarrhea in children on zinc therapy. Objective To assess the effect of zinc therapy in reducing the severity of acute bacterial and non-bacterial diarrhea. Method...

  16. Morphology control of zinc regeneration for zinc-air fuel cell and battery

    Science.gov (United States)

    Wang, Keliang; Pei, Pucheng; Ma, Ze; Xu, Huachi; Li, Pengcheng; Wang, Xizhong

    2014-12-01

    Morphology control is crucial both for zinc-air batteries and for zinc-air fuel cells during zinc regeneration. Zinc dendrite should be avoided in zinc-air batteries and zinc pellets are yearned to be formed for zinc-air fuel cells. This paper is mainly to analyze the mechanism of shape change and to control the zinc morphology during charge. A numerical three-dimensional model for zinc regeneration is established with COMSOL software on the basis of ionic transport theory and electrode reaction electrochemistry, and some experiments of zinc regeneration are carried out. The deposition process is qualitatively analyzed by the kinetics Monte Carlo method to study the morphological change from the electrocrystallization point of view. Morphological evolution of deposited zinc under different conditions of direct currents and pulse currents is also investigated by simulation. The simulation shows that parametric variables of the flowing electrolyte, the surface roughness and the structure of the electrode, the charging current and mode affect morphological evolution. The uniform morphology of deposited zinc is attained at low current, pulsating current or hydrodynamic electrolyte, and granular morphology is obtained by means of an electrode of discrete columnar structure in combination with high current and flowing electrolyte.

  17. Consequence of irrigation with arsenic and zinc contaminated water on accumulation of zinc in radishes plant

    Directory of Open Access Journals (Sweden)

    Hossein Banejad

    2014-10-01

    Conclusion: It was found that zinc concentration in radish roots, tubers, and leafs is correlated with the concentration of zinc in water. Moreover, there was a competition between the absorption of zinc and arsenic in plants. With increasing arsenic in irrigation water, transition of Zn was reduced to aerial part.

  18. Family Therapy

    Science.gov (United States)

    ... may be credentialed by the American Association for Marriage and Family Therapy (AAMFT). Family therapy is often short term. ... challenging situations in a more effective way. References Marriage and family therapists: The friendly mental health professionals. American Association ...

  19. Familial hypertriglyceridemia

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/000397.htm Familial hypertriglyceridemia To use the sharing features on this page, please enable JavaScript. Familial hypertriglyceridemia is a common disorder passed down through families. ...

  20. Family Meals

    Science.gov (United States)

    ... Teaching Kids to Be Smart About Social Media Family Meals KidsHealth > For Parents > Family Meals Print A ... even more important as kids get older. Making Family Meals Happen It can be a big challenge ...

  1. Family Arguments

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Family Life Medical Home Family Dynamics Adoption & Foster Care ... Life Listen Español Text Size Email Print Share Family Arguments Page Content Article Body We seem to ...

  2. Family History

    Science.gov (United States)

    Your family history includes health information about you and your close relatives. Families have many factors in common, including their genes, ... as heart disease, stroke, and cancer. Having a family member with a disease raises your risk, but ...

  3. Reversal of uraemic impotence by zinc.

    Science.gov (United States)

    Antoniou, L D; Shalhoub, R J; Sudhakar, T; Smith, J C

    1977-10-29

    In eight impotent haemodialysed men with low plasma-zinc levels sexual function, including potency, frequency of intercourse, libido, and plasma testosterone, follicle-stimulating hormone, and luteinising hormone levels, was determined before and after therapy with zinc (four patients) or placebo (four patients). Dialytic administration of zinc strikingly improved potency in all patients and raised the plasma-testosterone to normal in the two with low pretreatment plasma-testosterone levels. Placebo did not improve sexual function in any patient. Zinc deficiency is a reversible cause of gonadal dysfunction in uraemia.

  4. Zinc and Brass in Archaeological Perspective

    Directory of Open Access Journals (Sweden)

    J. S. Kharakwal

    2006-12-01

    Full Text Available Brass has a much longer history than zinc. There has been a bit of confusion about the early beginning of zinc as several claims are made out side of India. Both literary as well as archaeological records reveal that production of pure zinc had begun in the second half of the first millennium BC, though production on commercial scale begun in the early Medieval times. This paper attempts to examine the archaeological record and literary evidence to understand the actual beginning of brass and zinc in India.

  5. Zinc oxide varistor; Sanka aen barisuta

    Energy Technology Data Exchange (ETDEWEB)

    Igarashi, H.

    2000-01-01

    Characteristics of zinc oxide varistors, applications to electronic equipment protection and to power arrester are explained. Zinc oxide varistors were invented in Japan, which function by ceramics boundary phenomena and are applied to various fields from power plants to houses. Zinc oxide varistors protect electronic equipment from malfunctions and destructions by surge voltage, accordingly have spread rapidly. Protection performance of the power arresters has been improved by development of zinc oxide varistors for electric power, and power arresters came to be used to protect electric lines all over the world. (NEDO)

  6. Evolution of zinc morphology during continuous electrodeposition

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The morphology evolution of zinc continuous electrodeposits with nano-sized crystals on the ferrite substrate has been studied by in-situ scanning tunnel spectroscopy (STM). It is found that the morphology of zinc electrodeposits varies from initial granules with a size of about 30 nm to layered platelets with increasing deposition time. Meanwhile, the crystal structure of the zinc electrodeposits is identified to be hexagonal η-phase by X-ray diffraction. The orientation relationship between zinc crystals and the substrate surface can be interpreted in terms of the misfit and the atomic correspondence of the interphase boundary between the η-phase deposits and α-Fe substrate.

  7. Zinc absorption in inflammatory bowel disease

    Energy Technology Data Exchange (ETDEWEB)

    Valberg, L.S.; Flanagan, P.R.; Kertesz, A.; Bondy, D.C.

    1986-07-01

    Zinc absorption was measured in 29 patients with inflammatory bowel disease and a wide spectrum of disease activity to determine its relationship to disease activity, general nutritional state, and zinc status. Patients with severe disease requiring either supplementary oral or parenteral nutrition were excluded. The mean 65ZnCl2 absorption, in the patients, determined using a 65Zn and 51Cr stool-counting test, 45 +/- 17% (SD), was significantly lower than the values, 54 +/- 16%, in 30 healthy controls, P less than 0.05. Low 65ZnCl2 absorption was related to undernutrition, but not to disease activity in the absence of undernutrition or to zinc status estimated by leukocyte zinc measurements. Mean plasma zinc or leukocyte zinc concentrations in patients did not differ significantly from controls, and only two patients with moderate disease had leukocyte zinc values below the 5th percentile of normal. In another group of nine patients with inflammatory bowel disease of mild-to-moderate severity and minimal nutritional impairment, 65Zn absorption from an extrinsically labeled turkey test meal was 31 +/- 10% compared to 33 +/- 7% in 17 healthy controls, P greater than 0.1. Thus, impairment in 65ZnCl2 absorption in the patients selected for this study was only evident in undernourished persons with moderate or severe disease activity, but biochemical evidence of zinc deficiency was uncommon, and clinical features of zinc depletion were not encountered.

  8. Design and implementation of smart web sensors

    Directory of Open Access Journals (Sweden)

    Jevtić Nenad J.

    2015-01-01

    Full Text Available This paper presents the design and implementation of the smart web sensors. The paper briefly describes the concept of automatic configuration based on electronic specifications in industrial measurement and control systems as well as in distributed systems based on the OGC SWE family of standards. The model for the implementation of Plug and Play sensor in accordance with the IEEE 1451 family of standards is analyzed in detail. Special attention is paid to the network connectivity of analog sensors in accordance with IEEE 1451.4. The practical implementation of the 1451.4 compatible network processor for RTD temperature sensors and adequate software support for 1451.4 TEDS generation, are included in the paper.

  9. Graphene as a sensor material

    OpenAIRE

    Kochmann, Sven

    2014-01-01

    This thesis is concerned with the synthesis, characterization and utilization of (reduced) graphene oxide (chemically derived graphene) for sensor applications. The first chapter describes the history of graphene, classifies all members of the graphene family by convenient definitions, and outlines the motivation and aim of this work. Chapter 2 discusses several proof of principle and analytical concepts based on different graphene materials. These concepts point out the chemically deriv...

  10. Analysis of nanowire transistor based nitrogen dioxide gas sensor – A simulation study

    Directory of Open Access Journals (Sweden)

    Gaurav Saxena

    2015-06-01

    Full Text Available Sensors sensitivity, selectivity and stability has always been a prime design concern for gas sensors designers. Modeling and simulation of gas sensors aids the designers in improving their performance. In this paper, different routes for the modeling and simulation of a semiconducting gas sensor is presented. Subsequently, by employing one of the route, the response of Zinc Oxide nanowire transistor towards nitrogen dioxide ambient is simulated. In addition to the sensing mechanism, simulation study of gas species desorption by applying a recovery voltage is also presented.

  11. 家族性肌萎缩侧索硬化症患者及家系成员血中铜/锌超氧化物歧化酶活性及丙二醛水平变化与临床分型的关系%Relation of clinical type to the content of malondialdehyde and the activity of copper/zinc superoxide dismutase in patients with familial amyotrophic lateral sclerosis and their family members

    Institute of Scientific and Technical Information of China (English)

    王进; 罗杰峰; 梁秀龄

    2004-01-01

    背景:不同的铜 /锌超氧化物歧化酶( Copper/Zinc superoxide dismutase, Cu/ZnSOD)基因突变会使家族性肌萎缩侧索硬化 (family amyotropbic lateral sclerosis, FALS)产生不同的临床特征;丙二醛是过氧化脂降解的中间产物,可间接反映 Cu/ZnSOD的活性,但 Cu/ZnSOD活性及丙二醛水平改变与 FALS临床分型之间的关系尚不明确.若能探明前两者与后者的关系,将有助于 FALS的临床分型及亚临床诊断. 目的:探讨家族性肌萎缩侧索硬化症患者及家系成员 Cu/ZnSOD活性和丙二醛水平变化及 FALS的临床分型. 设计:随机病例对照研究. 地点和对象: 1998-09/1999-06共检测 7个家系的 32名成员,其中 3例先证者经中山医科大学第一附属院神经内科确诊( 1995年); 4例经广西医科大学附属第一医院神经内科确诊( 1997~ 1999年).将 32名成员分为 4组:汉族血统中有临床表现或有肌电图异常者归为第 1组(共 10例);各项检查均正常者的为第 2组(共 17例).壮族血统家系中有临床表现或肌电图异常者归为第 3组(共 3例);无临床表现、各项检查均正常者归为第 4组(共 2例). 72例对照组(第 5组)均来自 1999-01/1999-12到我院健康体检自愿者,其中男 38例,女 34例,年龄 15~ 59岁,平均 38.2岁. 方法:采用生物化学方法测定红细胞内 Cu/ZnSOD活性及丙二醛水平. 主要观察指标:外周血 SOD活性及丙二醛水平. 结果:第 1组 Cu/ZnSOD活性为( 316.68± 46.15) μ kat/g,丙二醛水平为( 8.08± 1.60) μ mol/L 1: 100溶血液,其中,有 4例 Cu/ZnSOD活性低于正常值, 3例丙二醛水平高于正常值,后者与前中的 3例为相同患者,无临床症状.第 2组 Cu/ZnSOD活性为( 351.74± 28.42) μ kat/g,丙二醛水平为( 6.55± 0.87) μ mol/L 1: 100溶血液,其中有 2例 Cu/ZnSOD活性低于正常对照组. 6例 Cu/ZnSOD活性低于正常值者及 3例丙二醛水平高于正常值者均集中见于 2个家系,并且与同

  12. Hydrogen sensor

    Science.gov (United States)

    Duan, Yixiang; Jia, Quanxi; Cao, Wenqing

    2010-11-23

    A hydrogen sensor for detecting/quantitating hydrogen and hydrogen isotopes includes a sampling line and a microplasma generator that excites hydrogen from a gas sample and produces light emission from excited hydrogen. A power supply provides power to the microplasma generator, and a spectrometer generates an emission spectrum from the light emission. A programmable computer is adapted for determining whether or not the gas sample includes hydrogen, and for quantitating the amount of hydrogen and/or hydrogen isotopes are present in the gas sample.

  13. A Rapid Process for Fabricating Gas Sensors

    Directory of Open Access Journals (Sweden)

    Chun-Ching Hsiao

    2014-07-01

    Full Text Available Zinc oxide (ZnO is a low-toxicity and environmentally-friendly material applied on devices, sensors or actuators for “green” usage. A porous ZnO film deposited by a rapid process of aerosol deposition (AD was employed as the gas-sensitive material in a CO gas sensor to reduce both manufacturing cost and time, and to further extend the AD application for a large-scale production. The relative resistance change (△R/R of the ZnO gas sensor was used for gas measurement. The fabricated ZnO gas sensors were measured with operating temperatures ranging from 110 °C to 180 °C, and CO concentrations ranging from 100 ppm to 1000 ppm. The sensitivity and the response time presented good performance at increasing operating temperatures and CO concentrations. AD was successfully for applied for making ZnO gas sensors with great potential for achieving high deposition rates at low deposition temperatures, large-scale production and low cost.

  14. Dosage Effect of Zinc Glycine Chelate on Zinc Metabolism and Gene Expression of Zinc Transporter in Intestinal Segments on Rat.

    Science.gov (United States)

    Huang, Danping; Hu, Qiaoling; Fang, Shenglin; Feng, Jie

    2016-06-01

    Zinc plays an essential role in various fundamental biological processes. The focus of this research was to investigate the dosage effect of zinc glycine chelate (Zn-Gly) on zinc metabolism and the gene expression of zinc transporters in intestinal segments. A total of 30 4-week-old SD rats were randomized into five treatment groups. The basal diets for each group were supplemented with gradient levels of Zn (0, 30, 60, 90, and 180 mg/kg) from Zn-Gly. After 1-week experiment, the results showed that serum and hepatic zinc concentration were elevated linearly with supplemental Zn levels from 0 to 180 mg Zn/kg. Serum Cu-Zn SOD activities resulted in a significant (P zinc levels (P zinc content and was significantly higher (P zinc levels and the activities of Cu-Zn SOD and AKP on rats. Dietary Zn-Gly has a certain effect on MT1, Zip4, Zip5, and ZnT1 expression, which expressed differently in intestinal segments with different levels of Zn-Gly load. Besides, Zn-Gly also could regulate PepT1 expression in intestinal segments.

  15. EOR-2 is an obligate binding partner of the BTB-zinc finger protein EOR-1 in Caenorhabditis elegans.

    Science.gov (United States)

    Howell, Kelly; Arur, Swathi; Schedl, Tim; Sundaram, Meera V

    2010-04-01

    BTB-zinc finger transcription factors play many important roles in metazoan development. In these proteins, the BTB domain is critical for dimerization and for recruiting cofactors to target genes. Identification of these cofactors is important for understanding how BTB-zinc finger proteins influence transcription. Here we show that the novel but conserved protein EOR-2 is an obligate binding partner of the BTB-zinc finger protein EOR-1 in Caenorhabditis elegans. EOR-1 and EOR-2 function together to promote multiple Ras/ERK-dependent cell fates during development, and we show that EOR-1 is a robust substrate of ERK in vitro. A point mutation (L81F) in the EOR-1 BTB domain reduces both ERK phosphorylation and EOR-2 binding and eliminates all detectable biological function without affecting EOR-1 expression levels, localization, or dimerization. This point mutation lies near the predicted charged pocket region of the EOR-1 BTB dimer, a region that, in other BTB-zinc finger proteins, has been proposed to interact with corepressors or coactivators. We also show that a conserved zinc finger-like motif in EOR-2 is required for binding to EOR-1, that the interaction between EOR-1 and EOR-2 is direct, and that EOR-2 can bind to the human BTB-zinc finger protein PLZF. We propose that EOR-2 defines a new family of cofactors for BTB-zinc finger transcription factors that may have conserved roles in other organisms.

  16. EOR-2 Is an Obligate Binding Partner of the BTB–Zinc Finger Protein EOR-1 in Caenorhabditis elegans

    Science.gov (United States)

    Howell , Kelly; Arur , Swathi; Schedl , Tim; Sundaram , Meera V.

    2010-01-01

    BTB-zinc finger transcription factors play many important roles in metazoan development. In these proteins, the BTB domain is critical for dimerization and for recruiting cofactors to target genes. Identification of these cofactors is important for understanding how BTB-zinc finger proteins influence transcription. Here we show that the novel but conserved protein EOR-2 is an obligate binding partner of the BTB-zinc finger protein EOR-1 in Caenorhabditis elegans. EOR-1 and EOR-2 function together to promote multiple Ras/ERK-dependent cell fates during development, and we show that EOR-1 is a robust substrate of ERK in vitro. A point mutation (L81F) in the EOR-1 BTB domain reduces both ERK phosphorylation and EOR-2 binding and eliminates all detectable biological function without affecting EOR-1 expression levels, localization, or dimerization. This point mutation lies near the predicted charged pocket region of the EOR-1 BTB dimer, a region that, in other BTB-zinc finger proteins, has been proposed to interact with corepressors or coactivators. We also show that a conserved zinc finger-like motif in EOR-2 is required for binding to EOR-1, that the interaction between EOR-1 and EOR-2 is direct, and that EOR-2 can bind to the human BTB-zinc finger protein PLZF. We propose that EOR-2 defines a new family of cofactors for BTB-zinc finger transcription factors that may have conserved roles in other organisms. PMID:20065070

  17. Longitudinal association between toenail zinc levels and the incidence of diabetes among American young adults: The CARDIA Trace Element Study.

    Science.gov (United States)

    Park, Jong Suk; Xun, Pengcheng; Li, Jing; Morris, Steve J; Jacobs, David R; Liu, Kiang; He, Ka

    2016-03-16

    Data on primary prevention of zinc status and diabetes risk are sparse and inconsistent. Of note, the previous studies measured either dietary zinc intake with questionnaire or zinc status in serum or hair. Toenail zinc levels are reliable biomarkers of a relatively long-term exposure. A total of 3,960 American young adults, aged 20-32 years, free of diabetes at baseline in 1987 when toenail clippings were collected, were examined for incident diabetes through 2010. Toenail zinc levels were measured with an inductively-coupled-plasma mass spectroscopy method. Incident diabetes cases were identified by fasting or non-fasting plasma glucose levels, oral glucose tolerance tests, hemoglobin A1C levels, and/or antidiabetic medications. During the 23-year follow-up, 418 incident diabetes occurred. After adjusted for age, sex, ethnicity, study center, body mass index, education, smoking status, alcohol consumption, physical activity, family history of diabetes, homeostasis model assessment of insulin resistance, and other dietary and non-dietary potential confounders, the hazard ratio of incident diabetes comparing the highest to the lowest quartile of toenail zinc levels was 1.21 (95% CI: 0.90-1.63; Ptrend = 0.20). Findings from this study do not support the hypothesis that zinc status is inversely and longitudinally associated with the incidence of diabetes in American young adults.

  18. Microcantilever sensor

    Science.gov (United States)

    Thundat, T.G.; Wachter, E.A.

    1998-02-17

    An improved microcantilever sensor is fabricated with at least one microcantilever attached to a piezoelectric transducer. The microcantilever is partially surface treated with a compound selective substance having substantially exclusive affinity for a targeted compound in a monitored atmosphere. The microcantilever sensor is also provided with a frequency detection means and a bending detection means. The frequency detection means is capable of detecting changes in the resonance frequency of the vibrated microcantilever in the monitored atmosphere. The bending detection means is capable of detecting changes in the bending of the vibrated microcantilever in the monitored atmosphere coactively with the frequency detection means. The piezoelectric transducer is excited by an oscillator means which provides a signal driving the transducer at a resonance frequency inducing a predetermined order of resonance on the partially treated microcantilever. Upon insertion into a monitored atmosphere, molecules of the targeted chemical attach to the treated regions of the microcantilever resulting in a change in oscillating mass as well as a change in microcantilever spring constant thereby influencing the resonant frequency of the microcantilever oscillation. Furthermore, the molecular attachment of the target chemical to the treated regions induce areas of mechanical strain in the microcantilever consistent with the treated regions thereby influencing microcantilever bending. The rate at which the treated microcantilever accumulates the target chemical is a function of the target chemical concentration. Consequently, the extent of microcantilever oscillation frequency change and bending is related to the concentration of target chemical within the monitored atmosphere. 16 figs.

  19. Zinc-regulated DNA binding of the yeast Zap1 zinc-responsive activator.

    Directory of Open Access Journals (Sweden)

    Avery G Frey

    Full Text Available The Zap1 transcription factor of Saccharomyces cerevisiae plays a central role in zinc homeostasis by controlling the expression of genes involved in zinc metabolism. Zap1 is active in zinc-limited cells and repressed in replete cells. At the transcriptional level, Zap1 controls its own expression via positive autoregulation. In addition, Zap1's two activation domains are regulated independently of each other by zinc binding directly to those regions and repressing activation function. In this report, we show that Zap1 DNA binding is also inhibited by zinc. DMS footprinting showed that Zap1 target gene promoter occupancy is regulated with or without transcriptional autoregulation. These results were confirmed using chromatin immunoprecipitation. Zinc regulation of DNA binding activity mapped to the DNA binding domain indicating other parts of Zap1 are unnecessary for this control. Overexpression of Zap1 overrode DNA binding regulation and resulted in constitutive promoter occupancy. Under these conditions of constitutive binding, both the zinc dose response of Zap1 activity and cellular zinc accumulation were altered suggesting the importance of DNA binding control to zinc homeostasis. Thus, our results indicated that zinc regulates Zap1 activity post-translationally via three independent mechanisms, all of which contribute to the overall zinc responsiveness of Zap1.

  20. Solubilization and Transformation of Insoluble Zinc Compounds by Fungi Isolated from a Zinc Mine

    Directory of Open Access Journals (Sweden)

    Thanawat Sutjaritvorakul

    2013-07-01

    Full Text Available Fungi were isolated from zinc-containing rocks and mining soil. They were screened for the ability to solubilize and transform three insoluble zinc compounds: ZnO, Zn3(PO4, and ZnCO3. Fungi were plated on potato dextrose agar (PDA medium which was supplemented with 0.5% (w/v of insoluble zinc compounds. Of the strains tested, four fungal isolates showed the highest efficiency for solubilizing all the insoluble zinc compounds, producing clearing zone diameters > 40 mm. These were identified as a Phomopsis spp., Aspergillus sp.1, Aspergillus sp.2, and Aspergillus niger. Zinc oxide was the most easily solubilized compound and it was found that 87%, 52%, and 61% of the tested fungi (23 isolates were able to solubilize zinc oxide, zinc phosphate, and zinc carbonate, respectively. Precipitation of zinc-containing crystals was observed in zinc oxide-containing agar medium underneath colonies of Aspergillus sp.1, and these were identified as zinc oxalate. It is suggested that these kinds of fungi have the potential application in bioremediation practices for heavy metal contaminated soils.

  1. Clinical Aspects of Trace Elements: Zinc in Human Nutrition - Assessment of Zinc Status

    Directory of Open Access Journals (Sweden)

    Michelle M Pluhator

    1996-01-01

    Full Text Available Because the limiting and vulnerable zinc pool has not been identified, it becomes a challenge to determine which of the many zinc pools is most susceptible to deficiency. As a consequence, defining and assessing zinc status in the individual patient is a somewhat uncertain process. Laboratory analysis of zinc status is difficult because no single biochemical criterion can reliably reflect zinc body stores. Many indexes have been examined in the hopes of discovering a method for the assessment of zinc nutriture. None of the methods currently used can be wholeheartedly recommended because they are fraught with problems that affect their use and interpretation. However, these methods remain in use for clinical and research purposes, though their benefits and drawbacks must always be acknowledged. Until an acceptable method of analysis is discovered, clinicians must rely for confirmation of zinc deficiency on a process of supplementing with zinc and observing the patient’s response. The main indexes (plasma/serum, erythrocyte, leukocyte, neutrophil, urine, hair and salivary zinc levels, taste acuity and oral zinc tolerance tests, and measurement of metallothionein levels are reviewed. Measurement of plasma or erythrocyte metallothionein levels shows promise as a future tool for the accurate determination of zinc status.

  2. The Potential for Zinc Stable Isotope Techniques and Modelling to Determine Optimal Zinc Supplementation

    Directory of Open Access Journals (Sweden)

    Cuong D. Tran

    2015-05-01

    Full Text Available It is well recognised that zinc deficiency is a major global public health issue, particularly in young children in low-income countries with diarrhoea and environmental enteropathy. Zinc supplementation is regarded as a powerful tool to correct zinc deficiency as well as to treat a variety of physiologic and pathologic conditions. However, the dose and frequency of its use as well as the choice of zinc salt are not clearly defined regardless of whether it is used to treat a disease or correct a nutritional deficiency. We discuss the application of zinc stable isotope tracer techniques to assess zinc physiology, metabolism and homeostasis and how these can address knowledge gaps in zinc supplementation pharmacokinetics. This may help to resolve optimal dose, frequency, length of administration, timing of delivery to food intake and choice of zinc compound. It appears that long-term preventive supplementation can be administered much less frequently than daily but more research needs to be undertaken to better understand how best to intervene with zinc in children at risk of zinc deficiency. Stable isotope techniques, linked with saturation response and compartmental modelling, also have the potential to assist in the continued search for simple markers of zinc status in health, malnutrition and disease.

  3. Arbuscular mycorrhiza and plant succesion on zinc smelter spoil heap in Katowice-Wełnowiec

    Directory of Open Access Journals (Sweden)

    Ewa Gucwa-Przepióra

    2014-01-01

    Full Text Available Mycorrhizal status of plants colonising the zinc wastes in Katowice was surveyed. In total 69 vascular plant species (25 families appearing on the investigated area have been noted. More than 60% of them were mycorrhizal. Non-mycorrhizal species, such as Cardaminopsis arenosa and Silene vulgaris dominated the early successional part of the zinc heap. Tussilago farfara was the only AM plant there, however, no arbuscules were developed at this stage. The number of AM species was increased on the 20 years old part of the zinc wastes and on the older 30-50 years old areas. AM plants constituted about 60% of the total number of species there. The frequency of particular AM species was the highest on the oldest part of the investigated area. The usefulness of the results for restoration practices was discussed.

  4. Calcium and zinc DTPA administration for internal contamination with plutonium-238 and americium-241.

    Science.gov (United States)

    Kazzi, Ziad N; Heyl, Alexander; Ruprecht, Johann

    2012-08-01

    The accidental or intentional release of plutonium or americium can cause acute and long term adverse health effects if they enter the human body by ingestion, inhalation, or injection. These effects can be prevented by rapid removal of these radionuclides by chelators such as calcium or zinc diethylenetriaminepentaacetate (calcium or zinc DTPA). These compounds have been shown to be efficacious in enhancing the elimination of members of the actinide family particularly plutonium and americium when administered intravenously or by nebulizer. The efficacy and adverse effects profile depend on several factors that include the route of internalization of the actinide, the type, and route time of administration of the chelator, and whether the calcium or zinc salt of DTPA is used. Current and future research efforts should be directed at overcoming limitations associated with the use of these complex drugs by using innovative methods that can enhance their structural and therapeutic properties.

  5. Intravenous zinc therapy for acquired zinc deficiency secondary to gastric bypass surgery: a case report.

    Science.gov (United States)

    Vick, Garrett; Mahmoudizad, Rod; Fiala, Katherine

    2015-01-01

    Zinc deficiency may result from either a congenitally inherited defect of zinc absorption or is acquired secondarily from a variety of factors affecting dietary zinc intake, absorption, or loss. We report a case of acquired zinc deficiency secondary to gastric bypass surgery that resulted in vulvar cutaneous manifestations of delayed onset, with failure to clear after oral supplementation with zinc. The patient experienced improvement of symptoms only after administration of intravenous zinc supplementation. Upon review of the current literature, it is thought that the patient's original suboptimal response to oral supplementation and improvement after receiving intravenous zinc were related to the intentional surgical alteration and bypass of the absorptive capacity of the duodenum and jejunum. With the current prevalence of obesity and availability of surgical weight loss therapies, it is important to be mindful of the resulting nutritional deficiencies, their clinical manifestations, and factors affecting the efficacy of therapeutic approaches as seen in this case.

  6. Family Privilege

    Science.gov (United States)

    Seita, John R.

    2014-01-01

    Family privilege is defined as "strengths and supports gained through primary caring relationships." A generation ago, the typical family included two parents and a bevy of kids living under one roof. Now, every variation of blended caregiving qualifies as family. But over the long arc of human history, a real family was a…

  7. Family Privilege

    Science.gov (United States)

    Seita, John R.

    2014-01-01

    Family privilege is defined as "strengths and supports gained through primary caring relationships." A generation ago, the typical family included two parents and a bevy of kids living under one roof. Now, every variation of blended caregiving qualifies as family. But over the long arc of human history, a real family was a…

  8. Molybdate based passivation of zinc

    DEFF Research Database (Denmark)

    Tang, Peter Torben; Bech-Nielsen, Gregers; Møller, Per

    1997-01-01

    In order to reduce corrosion rates, zinc plated parts are usually chromated. Recently chromates have caused increasingly environmental concern, for both allergic effects among workers touching chro-mated parts and toxic effects on fish, plants and bacteria. A molybdate based alternative has been...... developed to replace chromates in several passivation applica-tions. Depending on the environment in which the passivated parts are to be exposed, the protection that this alternative treatment provides range from less efficient to more efficient as compared to chromate. These aspects as well as issues...

  9. Bidirectional reflectance of zinc oxide

    Science.gov (United States)

    Scott, R.

    1973-01-01

    This investigation was undertaken to determine original and useful information about the bidirection reflectance of zinc oxide. The bidirectional reflectance will be studied for the spectra between .25-2.5 microns and the hemisphere above the specimen. The following factors will be considered: (1) surface conditions; (2) specimen preparation; (3) specimen substrate, (4) polarization; (5) depolarization; (6) wavelength; and (7) angles of incident and reflection. The bidirectional reflectance will be checked by experimentally determined angular hemispherical measurements or hemispherical measurements will be used to obtain absolute bidirectional reflectance.

  10. Sensors for Entertainment.

    Science.gov (United States)

    Lamberti, Fabrizio; Sanna, Andrea; Rokne, Jon

    2016-07-15

    Sensors are becoming ubiquitous in all areas of science, technology, and society. In this Special Issue on "Sensors for Entertainment", developments in progress and the current state of application scenarios for sensors in the field of entertainment is explored.

  11. DNA and RNA sensor

    Institute of Scientific and Technical Information of China (English)

    LIU; Tao; LIN; Lin; ZHAO; Hong; JIANG; Long

    2005-01-01

    This review summarizes recent advances in DNA sensor. Major areas of DNA sensor covered in this review include immobilization methods of DNA, general techniques of DNA detection and application of nanoparticles in DNA sensor.

  12. Zinc dosing and glucose tolerance in humans

    Energy Technology Data Exchange (ETDEWEB)

    Greenley, S.; Taylor, M.

    1986-03-05

    Animal data suggest the existence of a physiologic relationship between glucoregulatory hormones and zinc metabolism. In order to investigate this proposed relationship in humans, they examined the effect of moderately elevated plasma zinc levels on blood glucose clearance. Eight women (24-37 yrs) served as subjects for the study. Fasted volunteers were tested under two experimental conditions (a) ingestion of 50 g D-glucose (b) ingestion of 25 mg zinc followed 60 min later by ingestion of 50 g D-glucose. Five ml venous blood was drawn into trace-metal-free, fluoride-containing vacutainer tubes prior to and 15, 30, 45, 60, 90, and 120 min after glucose ingestion. Plasma was analyzed for glucose and zinc; glycemic responses were quantified by computing areas under the curves and times to peak concentration. Their human data indicate varied glycemic responses to the acute elevation of plasma zinc: 4 subjects showed little apparent effect; 3 subjects marginally increased either the area under the curve or time to peak and 1 subject (classified as suspect diabetic in the non-zinc condition) showed marked improvement in glycemic response following zinc ingestion. Their preliminary results suggest that blood glucose clearance may be affected in some individuals by the acute elevation of plasma zinc.

  13. Zinc anode alloy for sacrificial anodes

    Energy Technology Data Exchange (ETDEWEB)

    Jore, T.N.

    1984-02-13

    A zinc anode for sacrifical anodes, for preventing intercrystalline corrosion, comprises 0.10-050% by weight Al, 0.025-1.15% by weight Cd, and the remainder zinc and impurities caused by the production method, wherein the alloy also contains 0.01-1.0% magnesium.

  14. Poly(vinylidene fluoride)/zinc oxide smart composite material

    Science.gov (United States)

    Öğüt, Erdem; Yördem, O. Sinan; Menceloğlu, Yusuf Z.; Papila, Melih

    2007-04-01

    This work aimed at fabrication and electromechanical characterization of a smart material system composed of electroactive polymer and ceramic materials. The idea of composite material system is on account of complementary characteristics of the polymer and ceramic for flexibility and piezoelectric activity. Our preliminary work included Polyvinylidene Fluoride (PVDF) as the flexible piezoelectric polymer, and Zinc Oxide (ZnO) as the piezoelectric ceramic brittle, but capable to respond strains without poling. Two alternative processes were investigated. The first process makes use of ZnO fibrous formation achieved by sintering PVA/zinc acetate precursor fibers via electrospinning. Highly brittle fibrous ZnO mat was dipped into a PVDF polymer solution and then pressed to form pellets. The second process employed commercial ZnO nanopowder material. The powder was mixed into a PVDF/acetone polymer solution, and the resultant paste was pressed to form pellets. The free standing composite pellets with electrodes on the top and bottom surfaces were then subjected to sinusoidal electric excitation and response was recorded using a fotonic sensor. An earlier work on electrospun PVDF fiber mats was also summarized here and the electromechanical characterization is reported.

  15. Recent advances in zinc-air batteries.

    Science.gov (United States)

    Li, Yanguang; Dai, Hongjie

    2014-08-07

    Zinc-air is a century-old battery technology but has attracted revived interest recently. With larger storage capacity at a fraction of the cost compared to lithium-ion, zinc-air batteries clearly represent one of the most viable future options to powering electric vehicles. However, some technical problems associated with them have yet to be resolved. In this review, we present the fundamentals, challenges and latest exciting advances related to zinc-air research. Detailed discussion will be organized around the individual components of the system - from zinc electrodes, electrolytes, and separators to air electrodes and oxygen electrocatalysts in sequential order for both primary and electrically/mechanically rechargeable types. The detrimental effect of CO2 on battery performance is also emphasized, and possible solutions summarized. Finally, other metal-air batteries are briefly overviewed and compared in favor of zinc-air.

  16. AMPA receptor inhibition by synaptically released zinc.

    Science.gov (United States)

    Kalappa, Bopanna I; Anderson, Charles T; Goldberg, Jacob M; Lippard, Stephen J; Tzounopoulos, Thanos

    2015-12-22

    The vast amount of fast excitatory neurotransmission in the mammalian central nervous system is mediated by AMPA-subtype glutamate receptors (AMPARs). As a result, AMPAR-mediated synaptic transmission is implicated in nearly all aspects of brain development, function, and plasticity. Despite the central role of AMPARs in neurobiology, the fine-tuning of synaptic AMPA responses by endogenous modulators remains poorly understood. Here we provide evidence that endogenous zinc, released by single presynaptic action potentials, inhibits synaptic AMPA currents in the dorsal cochlear nucleus (DCN) and hippocampus. Exposure to loud sound reduces presynaptic zinc levels in the DCN and abolishes zinc inhibition, implicating zinc in experience-dependent AMPAR synaptic plasticity. Our results establish zinc as an activity-dependent, endogenous modulator of AMPARs that tunes fast excitatory neurotransmission and plasticity in glutamatergic synapses.

  17. Advances in wireless sensors and sensor networks

    CERN Document Server

    Mukhopadhyay, Subhas Chandra; Leung, Henry

    2010-01-01

    Written by experts, this book illustrates and collects recent advances in wireless sensors and sensor networks. It provides clever support for scientists, students and researchers in order to stimulate exchange and discussions for further developments.

  18. Zinc transporter Slc39a14 regulates inflammatory signaling associated with hypertrophic adiposity.

    Science.gov (United States)

    Troche, Catalina; Aydemir, Tolunay Beker; Cousins, Robert J

    2016-02-15

    Zinc is a signaling molecule in numerous metabolic pathways, the coordination of which occurs through activity of zinc transporters. The expression of zinc transporter Zip14 (Slc39a14), a zinc importer of the solute carrier 39 family, is stimulated under proinflammatory conditions. Adipose tissue upregulates Zip14 during lipopolysaccharide-induced endotoxemia. A null mutation of Zip14 (KO) revealed that phenotypic changes in adipose include increased cytokine production, increased plasma leptin, hypertrophied adipocytes, and dampened insulin signaling. Adipose tissue from KO mice had increased levels of preadipocyte markers, lower expression of the differentiation marker (PPARγ), and activation of NF-κB and STAT3 pathways. Our overall hypothesis was that ZIP14 would play a role in adipocyte differentiation and inflammatory obesity. Global Zip14 KO causes systemic endotoxemia. The observed metabolic changes in adipose metabolism were reversed when oral antibiotics were administrated, indicating that circulating levels of endotoxin were in part responsible for the adipose phenotype. To evaluate a mechanism, 3T3-L1 cells were differentiated into adipocytes and treated with siRNA to knock down Zip14. These cells had an impaired ability to mobilize zinc, which caused dysregulation of inflammatory pathways (JAK2/STAT3 and NF-κB). The Zip14 deletion may limit the availability of intracellular zinc, yielding the unique phenotype of inflammation coupled with hypertrophy. Taken together, these results suggest that aberrant zinc distribution observed with Zip14 ablation impacts adipose cytokine production and metabolism, ultimately increasing fat deposition when exposed to endotoxin. To our knowledge, this is the first investigation into the mechanistic role of ZIP14 in adipose tissue regulation and metabolism. Copyright © 2016 the American Physiological Society.

  19. Wireless sensor platform

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Pooran C.; Killough, Stephen M.; Kuruganti, Phani Teja

    2017-08-08

    A wireless sensor platform and methods of manufacture are provided. The platform involves providing a plurality of wireless sensors, where each of the sensors is fabricated on flexible substrates using printing techniques and low temperature curing. Each of the sensors can include planar sensor elements and planar antennas defined using the printing and curing. Further, each of the sensors can include a communications system configured to encode the data from the sensors into a spread spectrum code sequence that is transmitted to a central computer(s) for use in monitoring an area associated with the sensors.

  20. EDITORIAL: Humidity sensors Humidity sensors

    Science.gov (United States)

    Regtien, Paul P. L.

    2012-01-01

    produced at relatively low cost. Therefore, they find wide use in lots of applications. However, the method requires a material that possesses some conflicting properties: stable and reproducible relations between air humidity, moisture uptake and a specific property (for instance the length of a hair, the electrical impedance of the material), fast absorption and desorption of the water vapour (to obtain a short response time), small hysteresis, wide range of relative humidity (RH) and temperature-independent output (only responsive to RH). For these reasons, much research is done and is still going on to find suitable materials that combine high performance and low price. In this special feature, three of the four papers report on absorption sensors, all with different focus. Aziz et al describe experiments with newly developed materials. The surface structure is extensively studied, in view of its ability to rapidly absorb water vapour and exhibit a reproducible change in the resistance and capacitance of the device. Sanchez et al employ optical fibres coated with a thin moisture-absorbing layer as a sensitive humidity sensor. They have studied various coating materials and investigated the possibility of using changes in optical properties of the fibre (here the lossy mode resonance) due to a change in humidity of the surrounding air. The third paper, by Weremczuk et al, focuses on a cheap fabrication method for absorption-based humidity sensors. The inkjet technology appears to be suitable for mass fabrication of such sensors, which is demonstrated by extensive measurements of the electrical properties (resistance and capacitance) of the absorbing layers. Moreover, they have developed a model that describes the relation between humidity and the electrical parameters of the moisture-sensitive layer. Despite intensive research, absorption sensors still do not meet the requirements for high accuracy applications. The dew-point temperature method is more appropriate

  1. Thermodynamic Modeling of Zinc Speciation in Electric Arc Furnace Dust

    Science.gov (United States)

    Pickles, Chris A.

    2011-04-01

    The remelting of automobile scrap, containing galvanized steel, in an electric arc furnace (EAF) results in the generation of a dust, which contains considerable amounts of zinc and other metals. Typically, the amount of zinc is of significant commercial value, but the recovery of this metal can be hindered by the varied speciation of zinc. The majority of the zinc exists as zincite (ZnO) and zinc ferrite (ZnFe2O4) or ferritic spinels ((Zn x Mn y Fe1-x-y )Fe2O4), but other zinccontaining species such as zinc chloride, zinc hydroxide chlorides, hydrated zinc sulphates and zinc silicates have also been identified. There is a scarcity of research literature on the thermodynamic aspects of the formation of these zinc-containing species, in particular, the minor zinc-containing species. Therefore, in this study, the equilibrium module of HSC Chemistry® 6.1 was utilized to calculate the types and the amounts of the zinc-containing species. The variables studied were: the gas composition, the temperature and the dust composition. At high temperatures, zincite forms via the reaction of zinc vapour with oxygen gas and the zinc-manganese ferrites form as a result of the reaction of iron-manganese particles with zinc vapour and oxygen. At intermediate temperatures, zinc sulphates are produced through the reaction of zinc oxide and sulphur dioxide gas. As room temperature is approached, zinc chlorides and fluorides form by the reaction of zinc oxide with hydrogen chloride and hydrogen fluoride gases, respectively. Zinc silicate likely forms via the high temperature reaction of zinc vapour and oxygen with silica. In the presence of excess water and as room temperature is approached, the zinc sulphates, chlorides and fluorides can become hydrated.

  2. Zinc deficiency: a special challenge.

    Science.gov (United States)

    Hambidge, K Michael; Krebs, Nancy F

    2007-04-01

    In the development and testing of programs designed to improve complementary feeding globally, local nonfortified food-based solutions comprise an important strategy for the foreseeable future. These solutions are especially vital for the rural poor of less-developed countries. Zinc is notable among individual nutrients that have been designated as "problem" nutrients, adequate intake of which is difficult from complementary foods without fortification. This article considers the potential role of meat +/- liver in addressing this apparent problem. In a recent Colorado study, beef and cereal have been determined to be equally acceptable between age 5-7 mo as first and regular complementary foods. Average intake and absorption of Zn from beef by 7 mo of age, together with the modest intake/absorption of Zn from breast milk at that age, were adequate to meet average dietary and physiologic zinc requirements, respectively. Barriers to acceptability and availability of affordable meat are considered, but these are neither universal nor irresolvable in all populations.

  3. Modeling regulation of zinc uptake via ZIP transporters in yeast and plant roots.

    Directory of Open Access Journals (Sweden)

    Juliane Claus

    Full Text Available In yeast (Saccharomyces cerevisiae and plant roots (Arabidopsis thaliana zinc enters the cells via influx transporters of the ZIP family. Since zinc is both essential for cell function and toxic at high concentrations, tight regulation is essential for cell viability. We provide new insight into the underlying mechanisms, starting from a general model based on ordinary differential equations and adapting it to the specific cases of yeast and plant root cells. In yeast, zinc is transported by the transporters ZRT1 and ZRT2, which are both regulated by the zinc-responsive transcription factor ZAP1. Using biological data, parameters were estimated and analyzed, confirming the different affinities of ZRT1 and ZRT2 reported in the literature. Furthermore, our model suggests that the positive feedback in ZAP1 production has a stabilizing function at high influx rates. In plant roots, various ZIP transporters play a role in zinc uptake. Their regulation is largely unknown, but bZIP transcription factors are thought to be involved. We set up three putative models based on: an activator only, an activator with dimerization and an activator-inhibitor pair. These were fitted to measurements and analyzed. Simulations show that the activator-inhibitor model outperforms the other two in providing robust and stable homeostasis at reasonable parameter ranges.

  4. The effect of zinc deficiency and zinc supplementation on element levels in the bone tissue of ovariectomized rats: histopathologic changes.

    Science.gov (United States)

    Baltaci, Abdulkerim Kasim; Sunar, Fusun; Mogulkoc, Rasim; Acar, Musa; Toy, Hatice

    2014-05-01

    Study aimed to determine the effects of zinc supplementation/deficiency on the histological structure and elements levels in bone tissue in ovariectomized rats. The study included 40 Sprague-Dawley type adult female rats, divided as follows: Control, ovariectomized, ovariectomized + zinc supplemented, ovariectomized + zinc deficient groups. At the end of the study bone tissues (femur) were collected to determine the levels of calcium, phosphorus, magnesium, zinc, iron, aluminium, chrome, lithium, lead, nickel, and manganese. The bone tissue was examined for histopathology. Ovariectomy leaded to significant decrease in magnesium. Zinc supplementation to ovariectomized rats restored the reduced calcium, phosphorus, zinc. However, zinc deficiency in ovariectomized rats further reduced calcium, phosphorus, zinc, and manganese levels. Zinc deficiency in ovariectomized significantly increased Al, Cr, Li, Pb, and Ni levels. Tissue integrity was impaired due to ovariectomy and zinc deficiency. Ovariectomy and zinc deficiency leads significant decreases elements of the bone.

  5. Effects of zinc supplementation and zinc chelation on in vitro β-cell function in INS-1E cells

    DEFF Research Database (Denmark)

    Nygaard, Sanne Bjørn; Larsen, Agnete; Knuhtsen, Astrid;

    2014-01-01

    BACKGROUND: Zinc is essential for the activities of pancreatic β-cells, especially insulin storage and secretion. Insulin secretion leads to co-release of zinc which contributes to the paracrine communication in the pancreatic islets. Zinc-transporting proteins (zinc-regulated transporter, iron......-regulated transporter-like proteins [ZIPs] and zinc transporters [ZnTs]) and metal-buffering proteins (metallothioneins, MTs) tightly regulate intracellular zinc homeostasis. The present study investigated how modulation of cellular zinc availability affects β-cell function using INS-1E cells. RESULTS: Using INS-1E...... cells, we found that zinc supplementation and zinc chelation had significant effects on insulin content and insulin secretion. Supplemental zinc within the physiological concentration range induced insulin secretion. Insulin content was reduced by zinc chelation with N,N,N',N-tektrakis(2-pyridylmethyl...

  6. Zinc distribution in blood components, inflammatory status, and clinical indexes of disease activity during zinc supplementation in inflammatory rheumatic diseases.

    Science.gov (United States)

    Peretz, A; Nève, J; Jeghers, O; Pelen, F

    1993-05-01

    The effects of zinc supplementation on zinc status and on clinical and biological indicators of inflammation were investigated in 18 patients with chronic inflammatory rheumatic diseases and in 9 healthy control subjects. Patients with mild and recent onset disease were assigned to a 60-d trial to receive either 45 mg Zn (as gluconate)/d or a placebo, while control subjects received the zinc supplement. Baseline mean plasma zinc of the patients was low whereas mononuclear cell zinc content was elevated, suggesting a redistribution of the element related to the inflammatory process rather than to a zinc-deficient state. Zinc supplementation increased plasma zinc to a similar extent in patients and in control subjects, which suggested no impairment of zinc intestinal absorption as a result of the inflammatory process. On the contrary, erythrocyte and leukocyte zinc concentrations were not modified in the two groups examined. No beneficial effect of zinc treatment could be demonstrated on either clinical or inflammation indexes.

  7. Hydrothermal synthesis and acetylene sensing properties of variety low dimensional zinc oxide nanostructures.

    Science.gov (United States)

    Zhou, Qu; Chen, Weigen; Peng, Shudi; Zeng, Wen

    2014-01-01

    Various morphologies of low dimensional ZnO nanostructures, including spheres, rods, sheets, and wires, were successfully synthesized using a simple and facile hydrothermal method assisted with different surfactants. Zinc acetate dihydrate was chosen as the precursors of ZnO nanostructures. We found that polyethylene glycol (PEG), polyvinylpyrrolidone (PVP), glycine, and ethylene glycol (EG) play critical roles in the morphologies and microstructures of the synthesized nanostructures, and a series of possible growth processes were discussed in detail. Gas sensors were fabricated using screen-printing technology, and their sensing properties towards acetylene gas (C2H2), one of the most important arc discharge characteristic gases dissolved in oil-filled power equipments, were systematically measured. The ZnO nanowires based sensor exhibits excellent C2H2 sensing behaviors than those of ZnO nanosheets, nanorods, and nanospheres, indicating a feasible way to develop high-performance C2H2 gas sensor for practical application.

  8. Hydrothermal Synthesis and Acetylene Sensing Properties of Variety Low Dimensional Zinc Oxide Nanostructures

    Directory of Open Access Journals (Sweden)

    Qu Zhou

    2014-01-01

    Full Text Available Various morphologies of low dimensional ZnO nanostructures, including spheres, rods, sheets, and wires, were successfully synthesized using a simple and facile hydrothermal method assisted with different surfactants. Zinc acetate dihydrate was chosen as the precursors of ZnO nanostructures. We found that polyethylene glycol (PEG, polyvinylpyrrolidone (PVP, glycine, and ethylene glycol (EG play critical roles in the morphologies and microstructures of the synthesized nanostructures, and a series of possible growth processes were discussed in detail. Gas sensors were fabricated using screen-printing technology, and their sensing properties towards acetylene gas (C2H2, one of the most important arc discharge characteristic gases dissolved in oil-filled power equipments, were systematically measured. The ZnO nanowires based sensor exhibits excellent C2H2 sensing behaviors than those of ZnO nanosheets, nanorods, and nanospheres, indicating a feasible way to develop high-performance C2H2 gas sensor for practical application.

  9. Serum zinc levels in gestational diabetes

    Directory of Open Access Journals (Sweden)

    Rahimi Sharbaf F

    2008-12-01

    Full Text Available "nBackground: Maternal zinc deficiency during pregnancy has been related to adverse pregnancy outcomes. Most studies in which pregnant women have been supplemented with zinc to examine its effects on the outcome of the pregnancy have been carried out in industrialized countries and the results have been inconclusive. It has been shown that women with gestational diabetes (GDM have lower serum zinc levels than healthy pregnant women, and higher rates of macrosomia. Zinc is required for normal glucose metabolism, and strengthens the insulin-induced transportation of glucose into cells by its effect on the insulin signaling pathway. The purpose of this study was to assess the serum zinc levels of GDM patients and evaluate the effect of zinc supplementation. "nMethods: In the first stage of this prospective controlled study, we enrolled 70 women who were 24-28 weeks pregnant at the Prenatal Care Center of Mirza Kochak Khan Hospital, Tehran, Iran. The serum zinc level of each subject was determined. In the second stage, among these 70 subjects, the diabetics receiving insulin were divided into two groups, only one of which received a zinc supplement and the other group was the control group. Birth weight of neonates and insulin dosages were recorded. "nResults: The mean serum zinc level in the GDM group was lower than that of the control group (94.83 vs. 103.49mg/dl, respectively and the mean birth weight of neonates from the GDM women who received the zinc supplement was lower than that of the control group (3849g vs. 4136g. The rate of macrosomia was lower in the zinc supplemented group (20% vs. 53%. The mean of increase of insulin after receiving the zinc supplement was lower (8.4u vs. 13.53. "nConclusion: Maternal insulin resistance is associated with the accumulation of maternal fat tissue during early stages of pregnancy and greater fetoplacental nutrient availability in later stages, when 70% of fetal growth occurs, resulting in macrosomia. In

  10. Studies on the bioavailability of zinc in humans: intestinal interaction of tin and zinc.

    Science.gov (United States)

    Solomons, N W; Marchini, J S; Duarte-Favaro, R M; Vannuchi, H; Dutra de Oliveira, J E

    1983-04-01

    Mineral/mineral interactions at the intestinal level are important in animal nutrition and toxicology, but only limited understanding of their extent or importance in humans has been developed. An inhibitory interaction of dietary tin on zinc retention has been recently described from human metabolic studies. We have explored the tin/zinc interaction using the change-in-plasma-zinc-concentration method with a standard dosage of 12.5 mg of zinc as zinc sulfate in 100 ml of Coca-Cola. Sn/Zn ratios of 2:1, 4:1, and 8:1, constituted by addition of 25, 50, and 100 mg of tin as stannous chloride, had no significant overall effect on zinc uptake. The 100-mg dose of tin produced noxious gastrointestinal symptoms. Addition of iron as ferrous sulfate to form ratios of Sn/Fe/Zn of 1:1:1 and 2:2:1 with the standard zinc solution and the appropriate doses of tin produced a reduction of zinc absorption not dissimilar from that seen previously with zinc and iron alone, and addition of picolinic acid did not influence the uptake of zinc from the solution with the 2:2:1 Sn/Fe/Zn ratio.

  11. PREPARATION OF ZINC ENRICHED YEAST (SACCHAROMYCES CEREVISIAE BY CULTIVATION WITH DIFFERENT ZINC SALTS

    Directory of Open Access Journals (Sweden)

    Ľuboš Harangozo

    2012-02-01

    Full Text Available The yeast Saccharomyces cerevisiae is the best known microorganism and therefore widely used in many branches of industry. This study aims to investigate the accumulation of three inorganic zinc salts. Our research presents the ability of this yeast to absorb zinc from liquid medium and such enriched biomass use as a potential source of microelements in animal and/or human nutrition. It was found that the addition of different zinc forms, i.e. zinc nitrate, zinc sulphate and zinc chloride in fixed concentrations of 0, 25, 50 and 100 mg.100 ml-1 did not affect the amount of dry yeast biomass yielded, i.e. 1.0 – 1.2 g of yeast cells from 100 ml of cultivation medium, while higher presence of zinc solutions caused significantly lower yield of yeast biomass. The highest amount of zinc in yeast cells was achieved when added in the form of zinc nitrate in concentration of 200 mg.100 ml-1 YPD medium. The increment of intracellular zinc was up to 18.5 mg.g-1 of yeast biomass.

  12. Hyperaccumulation of zinc by zinc-depleted Candida utilis grown in chemostat culture.

    Science.gov (United States)

    Lawford, H G; Pik, J R; Lawford, G R; Williams, T; Kligerman, A

    1980-01-01

    The steady-state levels of zinc in Candida utilis yeast grown in continuous culture under conditions of zinc limitations are zinc-depleted cells from a zinc-limited chemostat possess the capacity to accumulate and store zinc at levels far in excess of the steady-state level of 4 nmol/mg dry biomass observed in carbon-limited chemostat cultures. Zinc uptake is energy-dependent and apparently undirectional since accumulated 65Zn neither exists from preloaded cells nor exchanges with cold Zn2+. The transport system exhibits a high affinity for Zn2+ (Km =.36micrM) with a Vmaxof 2.2 nmol per minute per milligram dry weight of cells. Growth during the period of the uptake assay is responsible for the apparent plateau level of 35 nmol Zn2+/mg dry weight of cells achieved after 20-30 min in the presence of 65Zn at pH 4.5 and 30 degrees C. Inhibition of growth during the uptake assay by cycloheximide results in a biphasic linear pattern of zinc accumulation where the cellular zinc is about 60 nmol/mg dry weight after 1 h. The enhanced level of accumulated zinc is not inhibtory to growth. Zinc-depleted C. utilis contains elevated amounts of polyphosphate and this anionic evidence does not allow discrimination between possible regulation of zinc homestasis either by inhibitions of zinc efflux through control of the membrane carrier or by control of the synthesis of a cytoplasmic zinc-sequestering macromolecule.

  13. DUF581 is plant specific FCS-like zinc finger involved in protein-protein interaction.

    Science.gov (United States)

    K, Muhammed Jamsheer; Laxmi, Ashverya

    2014-01-01

    Zinc fingers are a ubiquitous class of protein domain with considerable variation in structure and function. Zf-FCS is a highly diverged group of C2-C2 zinc finger which is present in animals, prokaryotes and viruses, but not in plants. In this study we identified that a plant specific domain of unknown function, DUF581 is a zf-FCS type zinc finger. Based on HMM-HMM comparison and signature motif similarity we named this domain as FCS-Like Zinc finger (FLZ) domain. A genome wide survey identified that FLZ domain containing genes are bryophytic in origin and this gene family is expanded in spermatophytes. Expression analysis of selected FLZ gene family members of A. thaliana identified an overlapping expression pattern suggesting a possible redundancy in their function. Unlike the zf-FCS domain, the FLZ domain found to be highly conserved in sequence and structure. Using a combination of bioinformatic and protein-protein interaction tools, we identified that FLZ domain is involved in protein-protein interaction.

  14. DUF581 is plant specific FCS-like zinc finger involved in protein-protein interaction.

    Directory of Open Access Journals (Sweden)

    Muhammed Jamsheer K

    Full Text Available Zinc fingers are a ubiquitous class of protein domain with considerable variation in structure and function. Zf-FCS is a highly diverged group of C2-C2 zinc finger which is present in animals, prokaryotes and viruses, but not in plants. In this study we identified that a plant specific domain of unknown function, DUF581 is a zf-FCS type zinc finger. Based on HMM-HMM comparison and signature motif similarity we named this domain as FCS-Like Zinc finger (FLZ domain. A genome wide survey identified that FLZ domain containing genes are bryophytic in origin and this gene family is expanded in spermatophytes. Expression analysis of selected FLZ gene family members of A. thaliana identified an overlapping expression pattern suggesting a possible redundancy in their function. Unlike the zf-FCS domain, the FLZ domain found to be highly conserved in sequence and structure. Using a combination of bioinformatic and protein-protein interaction tools, we identified that FLZ domain is involved in protein-protein interaction.

  15. An investigation into the influence of zinc precursor on the microstructural, photoluminescence, and gas-sensing properties of ZnO nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Catto, Ariadne C. [USP, Instituto de Física de São Carlos (Brazil); Silva, Luís F. da, E-mail: lfsilva83@gmail.com [UNESP, LIEC, Instituto de Química (Brazil); Bernardi, Maria I. B.; Li, Máximo S. [USP, Instituto de Física de São Carlos (Brazil); Longo, Elson [UNESP, LIEC, Instituto de Química (Brazil); Lisboa-Filho, Paulo N. [UNESP, Grupo de Materiais Avançados (MAv) (Brazil); Nascimento, Otaciro R.; Mastelaro, Valmor R. [USP, Instituto de Física de São Carlos (Brazil)

    2014-12-15

    This paper describes the effect of different zinc precursors, acetate, oxide, and nitrate, on the structure, microstructure, photoluminescence, and ozone gas-sensing properties of zinc oxide (ZnO) nanoparticles. Transmission and scanning electron microscopy, and BET surface area show a dependence of the particle size and surface area with the precursor type. The ZnO sample synthesized from zinc nitrate shows the best photoluminescence (PL) emission. Although electron paramagnetic resonance shows in all samples the presence of a g-signal attributed to oxygen vacancies, it is not possible to correlate the presence of these defects with PL emission behavior. Furthermore, ZnO sample synthesized from zinc nitrate also shows the best ozone gas-sensing response, however, our results do not allow correlating the best PL emission in the visible region with the best sensor response to ozone gas.

  16. Zinc Binding by Lactic Acid Bacteria

    Directory of Open Access Journals (Sweden)

    Jasna Mrvčić

    2009-01-01

    Full Text Available Zinc is an essential trace element in all organisms. A common method for the prevention of zinc deficiency is pharmacological supplementation, especially in a highly available form of a metalloprotein complex. The potential of different microbes to bind essential and toxic heavy metals has recently been recognized. In this work, biosorption of zinc by lactic acid bacteria (LAB has been investigated. Specific LAB were assessed for their ability to bind zinc from a water solution. Significant amount of zinc ions was bound, and this binding was found to be LAB species-specific. Differences among the species in binding performance at a concentration range between 10–90 mg/L were evaluated with Langmuir model for biosorption. Binding of zinc was a fast process, strongly influenced by ionic strength, pH, biomass concentration, and temperature. The most effective metal-binding LAB species was Leuconostoc mesenteroides (27.10 mg of Zn2+ per gram of dry mass bound at pH=5 and 32 °C, during 24 h. FT-IR spectroscopy analysis and electron microscopy demonstrated that passive adsorption and active uptake of the zinc ions were involved.

  17. Interactions of cadmium and zinc during pregnancy

    Energy Technology Data Exchange (ETDEWEB)

    Sorell, T.L.

    1988-01-01

    The interactions of cadmium exposure and zinc during pregnancy were investigated by studying rats exposed to 0, 5, 50, or 100 ppm cadmium (as CdCl{sub 2}) in the drinking water from day 6 to day 20 of pregnancy. On day 20 of pregnancy, fetuses of rats exposed to 50 and 100 ppm of cadmium were slightly but significantly smaller than those of control animals. Fetal weight was negatively correlated with fetal cadmium concentration and positively correlated with fetal cadmium concentration. Significant fetal cadmium accumulation occurred in both the 50 and 100 ppm cadmium exposure groups; fetal zinc concentrations were decreased. Maternal liver and kidney zinc concentrations were slightly elevated, and the possible role of maternal organ sequestration of available zinc is discussed. The activity of two zinc metalloenzymes, alkaline phosphatase and {delta}-aminolevulinic acid dehydratase, was decreased in maternal and fetal tissues, providing evidence of an alteration in zinc metabolism. In addition, the placental transport of {sup 65}Zn was characterized in control animals and compared to exposed groups; placental zinc transport was significantly decreased in the 50 and 100 ppm exposure groups.

  18. Zinc-Laccase Biofuel Cell

    Directory of Open Access Journals (Sweden)

    Abdul Aziz Ahmad

    2011-12-01

    Full Text Available A zinc-laccase biofuel cell adapting the zinc-air cell design features is investigated. A simple cell design configuration is employed: a membraneless single chamber and a freely suspended laccase in a quasi-neutral buffer electrolyte. The cell is characterised according to its open-circuit voltage, polarization profile, power density plot and discharge capacity at constant current. The biocatalytic role of laccase is evident from the polarization profile and power output plot. Performance comparison between a single chamber and dual chamber cell design is also presented. The biofuel cell possessed an open-circuit voltage of 1.2 V and delivered a maximum power density of 0.9 mW/cm2 at current density of 2.5 mA/cm2. These characteristics are comparable to biofuel cell utilising a much more complex system design.KEY WORDS (keyword:  Biofuel cell, Bioelectrochemical cell, Zinc anode, Laccase and Oxidoreductase.ABSTRAK: Sel bio-bahan api zink-laccase dengan adaptasi daripada ciri-ciri rekabentuk sel zink-udara telah dikaji. Sel dengan konfigurasi rekabentuk yang mudah digunapakai: ruangan tunggal tanpa membran dan laccase diampaikan secara bebas di dalam elektrolit pemampan quasi-neutral. Sel dicirikan berdasarkan voltan litar terbuka, profil polarisasi, plot ketumpatan kuasa dan kapasiti discas pada arus malar. Peranan laccase sebagai bio-pemangkin adalah amat ketara daripada profil polarisasi dan plot ketumpatan kuasa. Perbandingan prestasi di antara sel dengan rekabentuk ruangan tunggal and dwi-ruangan turut diketengahkan. Seperti dijangkakan, sel dengan rekabentuk ruangan tunggal menunjukkan kuasa keluaran yang lebih rendah jika dibandingkan dengan rekabentuk dwi-ruangan kemungkinan disebabkan fenomena cas bocor. Sel bio-bahan api ini mempunyai voltan litar terbuka 1.2 V dan memberikan ketumpatan kuasa maksima 0.9 mW/cm2 pada ketumpatan arus 2.5 mA/cm2. Ciri-ciri ini adalah sebanding dengan sel bio-bahan api yang menggunapakai rekabentuk sel

  19. Maternal zinc status is associated with breast milk zinc concentration and zinc status in breastfed infants aged 4-6 months.

    Science.gov (United States)

    Dumrongwongsiri, Oraporn; Suthutvoravut, Umaporn; Chatvutinun, Suthida; Phoonlabdacha, Phanphen; Sangcakul, Areeporn; Siripinyanond, Artitaya; Thiengmanee, Usana; Chongviriyaphan, Nalinee

    2015-01-01

    Breast milk provides adequate nutrients during the first 6 months of life. However, there are some reports of zinc deficiency in breastfed infants. This study was conducted to determine the prevalence of zinc deficiency in infants aged 4-6 months and the associated factors. Healthy infants aged 4-6 months and their mothers were enrolled. They were classified by feeding types as breastfed (BF), formula-fed (FF), and mixed groups (MF). Data collection included demographic data, perinatal data, given diets, and anthropometric measurement. Blood from infants and lactating mothers, and breast milk samples were collected to assess plasma and breast milk zinc concentrations. From 158 infants, the prevalence of zinc deficiency (plasma level below 10.7 mol/L) was 7.6%, and according to feeding groups 14.9%, 5.3%, and 2.9% in the BF, the FF, and the MF groups, respectively. Breastfed infants with zinc deficiency had significantly lower maternal zinc concentrations compared with those without zinc deficiency. There was a higher proportion of maternal zinc deficiency in zinc-deficient infants than those without zinc deficiency (66.7% vs 16.2%, p=0.02). There was a positive correlation between zinc concentrations in breast milk and plasma zinc concentrations of infants (r=0.62, p=0.01) and plasma zinc concentrations of lactating mothers (r=0.56, p=0.016). Using the regression analysis, infant zinc status was associated with maternal plasma zinc concentrations among breastfed infants. The results of this study suggest that breastfed infants aged 4-6 months may have a risk of zinc deficiency and that risk is associated with maternal zinc status and breast milk zinc concentrations.

  20. Pseudomonas aeruginosa capability to recruit zinc under conditions of limited metal availability is affected by inactivation of the ZnuABC transporter

    Science.gov (United States)

    D'Orazio, Melania; Mastropasqua, Maria Chiara; Cerasi, Mauro; Pacello, Francesca; Consalvo, Ada; Chirullo, Barbara; Mortensen, Brittany; Skaar, Eric P.; Ciavardelli, Domenico; Pasquali, Paolo; Battistoni, Andrea

    2015-01-01

    The ability of a large number of bacterial pathogens to multiply in the infected host and cause disease is dependent on their ability to express high affinity zinc importers. In many bacteria ZnuABC, a transporter of the ABC family, plays a central role in the process of zinc uptake in zinc poor environments, including the tissues of the infected host. To initiate an investigation into the relevance of the zinc uptake apparatus for Pseudomonas aeruginosa pathogenicity, we have generated a znuA mutant in the PA14 strain. We have found that this mutant strain displays a limited growth defect in zinc depleted media. The znuA mutant strain is more sensitive than the wild type strain to calprotectin-mediated growth inhibition, but both the strains are highly resistant to this zinc sequestering antimicrobial protein. Moreover, intracellular zinc content is not evidently affected by inactivation of the ZnuABC transporter. These findings suggest that P. aeruginosa is equipped with redundant mechanisms for the acquisition of zinc that might favor P. aeruginosa colonization of environments containing low levels of this metal. Nonetheless, deletion of znuA affects alginate production, reduces the activity of extracellular zinc-containing proteases, including LasA, LasB and Protease IV, and decreases the ability of P. aeruginosa to disseminate during systemic infections. These results indicate that efficient zinc acquisition is critical for the expression of various virulence features typical of P. aeruginosa and that ZnuABC also plays an important role in zinc homeostasis in this microorganism. PMID:25751674

  1. Implication of zinc excess on soil health.

    Science.gov (United States)

    Wyszkowska, Jadwiga; Boros-Lajszner, Edyta; Borowik, Agata; Baćmaga, Małgorzata; Kucharski, Jan; Tomkiel, Monika

    2016-01-01

    This study was undertaken to evaluate zinc's influence on the resistance of organotrophic bacteria, actinomyces, fungi, dehydrogenases, catalase and urease. The experiment was conducted in a greenhouse of the University of Warmia and Mazury (UWM) in Olsztyn, Poland. Plastic pots were filled with 3 kg of sandy loam with pHKCl - 7.0 each. The experimental variables were: zinc applied to soil at six doses: 100, 300, 600, 1,200, 2,400 and 4,800 mg of Zn(2+) kg(-1) in the form of ZnCl2 (zinc chloride), and species of plant: oat (Avena sativa L.) cv. Chwat and white mustard (Sinapis alba) cv. Rota. Soil without the addition of zinc served as the control. During the growing season, soil samples were subjected to microbiological analyses on experimental days 25 and 50 to determine the abundance of organotrophic bacteria, actinomyces and fungi, and the activity of dehydrogenases, catalase and urease, which provided a basis for determining the soil resistance index (RS). The physicochemical properties of soil were determined after harvest. The results of this study indicate that excessive concentrations of zinc have an adverse impact on microbial growth and the activity of soil enzymes. The resistance of organotrophic bacteria, actinomyces, fungi, dehydrogenases, catalase and urease decreased with an increase in the degree of soil contamination with zinc. Dehydrogenases were most sensitive and urease was least sensitive to soil contamination with zinc. Zinc also exerted an adverse influence on the physicochemical properties of soil and plant development. The growth of oat and white mustard plants was almost completely inhibited in response to the highest zinc doses of 2,400 and 4,800 mg Zn(2+) kg(-1).

  2. Wireless ferroelectric resonating sensor.

    Science.gov (United States)

    Viikari, Ville; Seppa, Heikki; Mattila, Tomi; Alastalo, Ari

    2010-04-01

    This paper presents a passive wireless resonating sensor that is based on a ferroelectric varactor. The sensor replies with its data at an intermodulation frequency when a reader device illuminates it at 2 closely located frequencies. The paper derives a theoretical equation for the response of such a sensor, verifies the theory by simulations, and demonstrates a temperature sensor based on a ferroelectric varactor.

  3. Integrated Optical Sensors

    NARCIS (Netherlands)

    Lambeck, Paul; Hoekstra, Hugo

    2003-01-01

    The optical (tele-) communication is the main driving force for the worldwide R&D on integrated optical devices and microsystems. lO-sensors have to compete with many other sensor types both within the optical domain (fiber sensors) and outside that domain, where sensors based on measurand induced c

  4. Integrated Optical Sensors

    NARCIS (Netherlands)

    Lambeck, Paul V.; Hoekstra, Hugo

    2003-01-01

    The optical (tele-) communication is the main driving force for the worldwide R&D on integrated optical devices and microsystems. lO-sensors have to compete with many other sensor types both within the optical domain (fiber sensors) and outside that domain, where sensors based on measurand induced c

  5. Familial gigantism

    NARCIS (Netherlands)

    W.W. de Herder (Wouter)

    2012-01-01

    textabstractFamilial GH-secreting tumors are seen in association with three separate hereditary clinical syndromes: multiple endocrine neoplasia type 1, Carney complex, and familial isolated pituitary adenomas.

  6. Familial gigantism

    Directory of Open Access Journals (Sweden)

    Wouter W. de Herder

    2012-01-01

    Full Text Available Familial GH-secreting tumors are seen in association with three separate hereditary clinical syndromes: multiple endocrine neoplasia type 1, Carney complex, and familial isolated pituitary adenomas.

  7. Familial dermographism.

    Science.gov (United States)

    Jedele, K B; Michels, V V

    1991-05-01

    Urticaria in response to various physical stimuli has been reported in sporadic and familial patterns. The most common of these physical urticarias, dermographism, is a localized urticarial response to stroking or scratching of the skin and has not been reported previously to be familial. A four-generation family with dermographism, probably inherited as an autosomal dominant trait, is presented along with a discussion of sporadic dermographism and other types of familial physical urticarias.

  8. Clinical Aspects of Trace Elements: Zinc in Human Nutrition – Zinc Deficiency and Toxicity

    Directory of Open Access Journals (Sweden)

    Michelle M Pluhator

    1996-01-01

    Full Text Available Available evidence suggests that trace elements, such as zinc, once thought to have no nutritional relevance, are possibly deficient in large sections of the human population. Conditioned deficiencies have been reported to result from malabsorption syndromes, acrodermatitis enteropathica, alcoholism, gastrointestinal disease, thermal injury, chronic diseases (eg, diabetes, sickle cell anemia, and in total parenteral nutrition therapy. Awareness that patients with these problems are at risk has led health professionals to focus increasingly on the importance of zinc therapy in the prevention and treatment of deficiency. More recently zinc toxicity and its role in human nutrition and well-being have come under investigation. Reports have focused on the role of zinc toxicity in causes of copper deficiency, changes in the immune system and alterations in blood lipids. As the numerous challenges presented by the study of zinc in human nutrition are met, more appropriate recommendations for dietary and therapeutic zinc intake are being made.

  9. Preparation of zinc oxide particles by using layered basic zinc acetate as a precursor

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Lanqin, E-mail: lanqin_tang@ycit.edu.cn [College of Chemical and Biological Engineering, Yancheng Institute of Technology, 9 Yingbin Avenue, Yancheng 224051 (China); College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Ding, Xuefeng; Zhao, Xu; Wang, Zichen; Zhou, Bing [College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012 (China)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer A simple aqueous solution process has been applied to prepare zinc oxide particles. Black-Right-Pointing-Pointer This novel method exempts traditional calcinations. Black-Right-Pointing-Pointer Various zinc oxide particles are obtained. - Abstract: TEA and NaOH are applied to transform layered basic zinc acetate into zinc oxide particles by a simple aqueous solution process (<100 Degree-Sign C). Zinc oxide with different morphologies, including dumbbells, earthnuts, ellipsoids and hexagonal pillars, are obtained by carefully controlling the amounts of sodium hydroxide, triethanolamine, and reaction temperature. Field emission scanning electron microscope images, X-ray powder diffraction patterns, X-ray photoelectron spectroscopy spectra and room-temperature photoluminescence spectra are used to characterize final products. Furthermore, a possible growth mechanism is discussed in this paper. This easy procedure for zinc oxide fabrication offers the possibility of a generalized approach to the production of metal oxide with tunable morphology.

  10. Zinc Deficiency in Humans and its Amelioration

    OpenAIRE

    Yashbir Singh Shivay

    2015-01-01

    Zinc (Zn) deficiency in humans has recently received considerable attention. Global mortality in children under 5 years of age in 2004 due to Zn deficiency was estimated at 4,53,207 as against 6,66,771 for vitamin A deficiency; 20,854 for iron deficiency and 3,619 for iodine deficiency. In humans 2800-3000 proteins contain Zn prosthetic group and Zn is an integral component of zinc finger prints that regulate DNA transcription. Zinc is a Type-2 nutrient, which means that its concentration in ...

  11. The zinc dyshomeostasis hypothesis of Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Travis J A Craddock

    Full Text Available Alzheimer's disease (AD is the most common form of dementia in the elderly. Hallmark AD neuropathology includes extracellular amyloid plaques composed largely of the amyloid-β protein (Aβ, intracellular neurofibrillary tangles (NFTs composed of hyper-phosphorylated microtubule-associated protein tau (MAP-tau, and microtubule destabilization. Early-onset autosomal dominant AD genes are associated with excessive Aβ accumulation, however cognitive impairment best correlates with NFTs and disrupted microtubules. The mechanisms linking Aβ and NFT pathologies in AD are unknown. Here, we propose that sequestration of zinc by Aβ-amyloid deposits (Aβ oligomers and plaques not only drives Aβ aggregation, but also disrupts zinc homeostasis in zinc-enriched brain regions important for memory and vulnerable to AD pathology, resulting in intra-neuronal zinc levels, which are either too low, or excessively high. To evaluate this hypothesis, we 1 used molecular modeling of zinc binding to the microtubule component protein tubulin, identifying specific, high-affinity zinc binding sites that influence side-to-side tubulin interaction, the sensitive link in microtubule polymerization and stability. We also 2 performed kinetic modeling showing zinc distribution in extra-neuronal Aβ deposits can reduce intra-neuronal zinc binding to microtubules, destabilizing microtubules. Finally, we 3 used metallomic imaging mass spectrometry (MIMS to show anatomically-localized and age-dependent zinc dyshomeostasis in specific brain regions of Tg2576 transgenic, mice, a model for AD. We found excess zinc in brain regions associated with memory processing and NFT pathology. Overall, we present a theoretical framework and support for a new theory of AD linking extra-neuronal Aβ amyloid to intra-neuronal NFTs and cognitive dysfunction. The connection, we propose, is based on β-amyloid-induced alterations in zinc ion concentration inside neurons affecting stability of

  12. Zinc and biotin deficiencies after pancreaticoduodenectomy.

    Science.gov (United States)

    Yazbeck, N; Muwakkit, S; Abboud, M; Saab, R

    2010-01-01

    We report zinc and biotin deficiencies after pancreaticoduodenectomy in a 16 year old female presenting clinically with marked alopecia, total body hair loss, dry skin with scales, and maculopathy with significant vision loss. These micronutrient deficiencies likely occurred due to resection of the duodenum and proximal jejunum, sites of primary absorption of several micronutrients and their protein carriers, including zinc and biotin. Early diagnosis is essential to prevent irreversible sequelae. Adequate supplementation of zinc and biotin as well as dietary advice is needed for clinical improvement.

  13. Thermally induced microstrain broadening in hexagonal zinc

    Energy Technology Data Exchange (ETDEWEB)

    Lawson, Andrew C [Los Alamos National Laboratory; Valdez, James A [Los Alamos National Laboratory; Roberts, Joyce A [Los Alamos National Laboratory; Leineweber, Andreas [STUTTGART, GERMANY; Mittemeijer, E J [STUTTGART, GERMANY; Kreher, W [DRESDEN UNIV

    2008-01-01

    Neutron powder-diffraction experiments on polycrystalline hexagonal zinc show considerable temperature-dependent line broadening. Whereas as-received zinc at 300 K exhibits narrow reflections, during cooling to a minimum temperature of 10K considerable line-broadening appears, which largely disappears again during reheating. The line broadening may be ascribed to microstrains induced by thermal microstresses due to the anisotropy of the thermal expansion (shrinkage) of hexagonal zinc. Differences between the thermal microstrains and theoretical predictions considering elastic deformation of the grains can be explained by plastic deformation and surface effects.

  14. Zinc therapy for different causes of diarrhea

    OpenAIRE

    Hafaz Zakky Abdillah; Supriatmo; Melda Deliana; Selvi Nafianti; Atan Baas Sinuhaji

    2013-01-01

    Background The incidence of diarrhea in Indonesia has declined in the past five years. In spite of the increasing number of studies on the treatment for acute diarrhea, especially the use of zinc, it is not known if bacterial vs. non-bacterial etiology makes a difference in the reduction of severity of acute diarrhea in children on zinc therapy. Objective To assess the effect of zinc therapy in reducing the severity of acute bacterial and non-bacterial diarrhea. Methods We performed a...

  15. Zinc supplementation in burn patients.

    Science.gov (United States)

    Caldis-Coutris, Nancy; Gawaziuk, Justin P; Logsetty, Sarvesh

    2012-01-01

    Micronutrient supplementation is a common practice throughout many burn centers across North America; however, uncertainty pertaining to dose, duration, and side effects of such supplements persists. The authors prospectively collected data from 23 hospitalized patients with burn sizes ranging from 10 to 93% TBSA. Each patient received a daily multivitamin and mineral supplement, 50 mg zinc (Zn) daily, and 500 mg vitamin C twice daily. Supplements were administered orally or enterally. Albumin, prealbumin, C-reactive protein, serum Zn, and serum copper were measured weekly during hospital admission until levels were within normal reference range. Our study concluded that 50 mg daily dose of Zn resulted in normal serum levels in 19 of 23 patients at discharge; 50 mg Zn supplementation did not interfere with serum copper levels; and Zn supplements, regardless of administration route, did not result in gastrointestinal side effects.

  16. PERANCANGAN DAN IMPLEMENTASI SENSOR PARKIR PADA MOBIL MENGGUNAKAN SENSOR ULTRASONIK

    Directory of Open Access Journals (Sweden)

    Rudy Susanto

    2007-05-01

    Full Text Available A car driver often had trouble to park his car a narrow location, caused by a narrow parking area on the wane.Also, cars had often crashed the electric pillar or scratched the car on the wall while retreat. The problem was the driverdidn’t know condition behind vehicle because of limited of view. The research aimed to make a system that can easily helpdriver in parking his car, by using of ultrasonic parking sensor. The method used in sensor scheme parks is ultrasonicisensor to detect and measure car and balk distance by utilising of 851 family microcontroller as the main system. Theresult indicates that ultrasonic censor effective deep measurement was on distance of 2 cm – 30 m. It is that enoughultrasonic censor is effective to be implemented on censor parks.

  17. Isolation and characterization of Lotus japonicus genes involved in iron and zinc homeostasis

    DEFF Research Database (Denmark)

    Cvitanich, Cristina; Jensen, Winnie; Sandal, Niels Nørgaard;

    in plants. We have used these sequences to search for L. japonicus ESTs and genomic loci that are likely to be involved in iron and zinc metabolism. We have identified sequences corresponding to ferritins, ferric reductases, metal transport proteins of the ZIP family, and cation transporters of the NRAMP....... japonicus Gifu recombinant inbred lines....

  18. Effects of zinc transporters on Cryptococcus gattii virulence

    OpenAIRE

    Schneider, Rafael de Oliveira; Diehl, Camila; dos Santos, Francine Melise; Piffer, Alícia Corbellini; Garcia, Ane Wichine Acosta; Kulmann, Marcos Iuri Roos; Schrank, Augusto; Kmetzsch, Lívia; Vainstein, Marilene Henning; Staats, Charley C.

    2015-01-01

    Zinc is an essential nutrient for all living organisms because it is a co-factor of several important proteins. Furthermore, zinc may play an essential role in the infectiousness of microorganisms. Previously, we determined that functional zinc metabolism is associated with Cryptococcus gattii virulence. Here, we characterized the ZIP zinc transporters in this human pathogen. Transcriptional profiling revealed that zinc levels regulated the expression of the ZIP1, ZIP2 and ZIP3 genes, althoug...

  19. First Principles Investigation of Zinc-anode Dissolution in Zinc-air Batteries

    OpenAIRE

    Siahrostami, Samira; Tripkovic, Vladimir; Lundgård, Keld Troen; Jensen, Kristian E.; Hansen, Heine A.; Hummelshøj, Jens Strabo; Mýrdal, Jón Steinar Garðarsson; Vegge, Tejs; Nørskov, Jens K.; Rossmeisl, Jan

    2013-01-01

    With surging interest in high energy density batteries, much attention has recently been devoted to metal-air batteries. The zinc-air battery has been known for more than hundred years and is commercially available as a primary battery, but recharging has remained elusive; in part because the fundamental mechanisms still remain to be fully understood. Here, we present a density functional theory investigation of the zinc dissolution (oxidation) on the anode side in the zinc-air battery. Two m...

  20. Sensor sentinel computing device

    Science.gov (United States)

    Damico, Joseph P.

    2016-08-02

    Technologies pertaining to authenticating data output by sensors in an industrial environment are described herein. A sensor sentinel computing device receives time-series data from a sensor by way of a wireline connection. The sensor sentinel computing device generates a validation signal that is a function of the time-series signal. The sensor sentinel computing device then transmits the validation signal to a programmable logic controller in the industrial environment.

  1. Coordinated Zinc Homeostasis Is Essential for the Wild-Type Virulence of Brucella abortus

    Science.gov (United States)

    Sheehan, Lauren M.; Budnick, James A.; Roop, R. Martin

    2015-01-01

    ABSTRACT Metal homeostasis in bacterial cells is a highly regulated process requiring intricately coordinated import and export, as well as precise sensing of intracellular metal concentrations. The uptake of zinc (Zn) has been linked to the virulence of Brucella abortus; however, the capacity of Brucella strains to sense Zn levels and subsequently coordinate Zn homeostasis has not been described. Here, we show that expression of the genes encoding the zinc uptake system ZnuABC is negatively regulated by the Zn-sensing Fur family transcriptional regulator, Zur, by direct interactions between Zur and the promoter region of znuABC. Moreover, the MerR-type regulator, ZntR, controls the expression of the gene encoding the Zn exporter ZntA by binding directly to its promoter. Deletion of zur or zntR alone did not result in increased zinc toxicity in the corresponding mutants; however, deletion of zntA led to increased sensitivity to Zn but not to other metals, such as Cu and Ni, suggesting that ZntA is a Zn-specific exporter. Strikingly, deletion of zntR resulted in significant attenuation of B. abortus in a mouse model of chronic infection, and subsequent experiments revealed that overexpression of zntA in the zntR mutant is the molecular basis for its decreased virulence. IMPORTANCE The importance of zinc uptake for Brucella pathogenesis has been demonstrated previously, but to date, there has been no description of how overall zinc homeostasis is maintained and genetically controlled in the brucellae. The present work defines the predominant zinc export system, as well as the key genetic regulators of both zinc uptake and export in Brucella abortus. Moreover, the data show the importance of precise coordination of the zinc homeostasis systems as disregulation of some elements of these systems leads to the attenuation of Brucella virulence in a mouse model. Overall, this study advances our understanding of the essential role of zinc in the pathogenesis of

  2. Effect of Zinc on Efficacy of Iron Supplementation in Improving Iron and Zinc Status in Women

    Directory of Open Access Journals (Sweden)

    Phuong Nguyen

    2012-01-01

    Full Text Available Iron and zinc may interact in micronutrient supplements and thereby decrease efficacy. We investigated interactive effects of combined zinc and iron supplementation in a randomized controlled trial conducted in 459 Guatemalan women. Four groups were supplemented for 12 weeks: (1 weekly iron and folic acid (IFA; (2 weekly IFA and 30 mg zinc; (3 daily IFA; (4 daily IFA and 15 mg zinc. Effects were assessed by generalized linear regression. Baseline hemoglobin (Hb concentration was 137.4±15.5 g/L, 13% were anemic and 54% had zinc deficiency. Hb cconcentrations were similar by supplement type, but Hb concentrations improved significantly in anemic women at baseline (increase of 21.8 g/L. Mean percentage changes in serum ferritin were significantly higher in daily compared to weekly supplemented groups (86% versus 32%. The addition of zinc to IFA supplements had no significant impact on iron or zinc status. In conclusion, adding zinc to IFA supplements did not modify efficacy on iron status or improve zinc status, but daily supplementation was more efficacious than weekly in improving iron stores.

  3. Associations between Dietary Iron and Zinc Intakes, and between Biochemical Iron and Zinc Status in Women

    Directory of Open Access Journals (Sweden)

    Karen Lim

    2015-04-01

    Full Text Available Iron and zinc are found in similar foods and absorption of both may be affected by food compounds, thus biochemical iron and zinc status may be related. This cross-sectional study aimed to: (1 describe dietary intakes and biochemical status of iron and zinc; (2 investigate associations between dietary iron and zinc intakes; and (3 investigate associations between biochemical iron and zinc status in a sample of premenopausal women aged 18–50 years who were recruited in Melbourne and Sydney, Australia. Usual dietary intakes were assessed using a 154-item food frequency questionnaire (n = 379. Iron status was assessed using serum ferritin and hemoglobin, zinc status using serum zinc (standardized to 08:00 collection, and presence of infection/inflammation using C-reactive protein (n = 326. Associations were explored using multiple regression and logistic regression. Mean (SD iron and zinc intakes were 10.5 (3.5 mg/day and 9.3 (3.8 mg/day, respectively. Median (interquartile range serum ferritin was 22 (12–38 μg/L and mean serum zinc concentrations (SD were 12.6 (1.7 μmol/L in fasting samples and 11.8 (2.0 μmol/L in nonfasting samples. For each 1 mg/day increase in dietary iron intake, zinc intake increased by 0.4 mg/day. Each 1 μmol/L increase in serum zinc corresponded to a 6% increase in serum ferritin, however women with low serum zinc concentration (AM fasting < 10.7 μmol/L; AM nonfasting < 10.1 μmol/L were not at increased risk of depleted iron stores (serum ferritin <15 μg/L; p = 0.340. Positive associations were observed between dietary iron and zinc intakes, and between iron and zinc status, however interpreting serum ferritin concentrations was not a useful proxy for estimating the likelihood of low serum zinc concentrations and women with depleted iron stores were not at increased risk of impaired zinc status in this cohort.

  4. Measurement of Zinc Absorption From Meals: Comparison of Extrinsi Zinc Labeling and Independent Measurements of Dietary Zinc Absorption

    Science.gov (United States)

    Sheng, Xiao-Yang; Hambidge, K. Michael; Miller, Leland V.; Westcott, Jamie E.; Lei, Sian; Krebs, Nancy F.

    2017-01-01

    Background Extrinsic labeling techniques are typically used to measure fractional absorption of zinc (FAZextrinsic) but none have been adequately evaluated. Objective To compare determination of the quantity of zinc absorbed (TAZextrinsic) using measurements of FAZextrinsic with results of simultaneous determinations of dietary zinc absorbed (TAZmetabolic) that are not dependent on labeling ingested food with an extrinsic tracer (modified metabolic balance technique). Design 70Zn was administered orally with all meals for 6 consecutive days to 21 healthy, free-living adult women consuming a constant diet. 68Zn and 67Zn were administered intravenously. FAZextrinsic was measured using a dual isotope tracer ratio technique and multiplied by dietary zinc to give TAZextrinsic TAZmetabolic was determined by addition of net absorption of zinc and endogenous fecal zinc, the latter determined by an isotope dilution technique. Results TAZextrinsic and TAZmetabolic were 3.0 ± 1.1mg/day and 3.1 ± 1.1 mg/day respectively, paired t-test p = 0.492. The correlation coefficient for TAZextrinsic and TAZmetabolic was 0.91, and for FAZextrinsic and FAZmetabolic was 0.95. A Bland Altman analysis indicated a bias of 0.07, and the limits of agreement of −0.86 to 1.01 for TAZextrinsic and TAZmatabolic Conclusion These results from two independent methods provide reasonable validation of our extrinsic labeling technique for a wide range of composite diets. PMID:20209474

  5. Zinc and its importance for human health: An integrative review.

    Science.gov (United States)

    Roohani, Nazanin; Hurrell, Richard; Kelishadi, Roya; Schulin, Rainer

    2013-02-01

    Since its first discovery in an Iranian male in 1961, zinc deficiency in humans is now known to be an important malnutrition problem world-wide. It is more prevalent in areas of high cereal and low animal food consumption. The diet may not necessarily be low in zinc, but its bio-availability plays a major role in its absorption. Phytic acid is the main known inhibitor of zinc. Compared to adults, infants, children, adolescents, pregnant, and lactating women have increased requirements for zinc and thus, are at increased risk of zinc depletion. Zinc deficiency during growth periods results in growth failure. Epidermal, gastrointestinal, central nervous, immune, skeletal, and reproductive systems are the organs most affected clinically by zinc deficiency. Clinical diagnosis of marginal Zn deficiency in humans remains problematic. So far, blood plasma/serum zinc concentration, dietary intake, and stunting prevalence are the best known indicators of zinc deficiency. Four main intervention strategies for combating zinc deficiency include dietary modification/diversification, supplementation, fortification, and bio-fortification. The choice of each method depends on the availability of resources, technical feasibility, target group, and social acceptance. In this paper, we provide a review on zinc biochemical and physiological functions, metabolism including, absorption, excretion, and homeostasis, zinc bio-availability (inhibitors and enhancers), human requirement, groups at high-risk, consequences and causes of zinc deficiency, evaluation of zinc status, and prevention strategies of zinc deficiency.

  6. Zinc and its importance for human health: An integrative review

    Directory of Open Access Journals (Sweden)

    Nazanin Roohani

    2013-01-01

    Full Text Available Since its first discovery in an Iranian male in 1961, zinc deficiency in humans is now known to be an important malnutrition problem world-wide. It is more prevalent in areas of high cereal and low animal food consumption. The diet may not necessarily be low in zinc, but its bio-availability plays a major role in its absorption. Phytic acid is the main known inhibitor of zinc. Compared to adults, infants, children, adolescents, pregnant, and lactating women have increased requirements for zinc and thus, are at increased risk of zinc depletion. Zinc deficiency during growth periods results in growth failure. Epidermal, gastrointestinal, central nervous, immune, skeletal, and reproductive systems are the organs most affected clinically by zinc deficiency. Clinical diagnosis of marginal Zn deficiency in humans remains problematic. So far, blood plasma/serum zinc concentration, dietary intake, and stunting prevalence are the best known indicators of zinc deficiency. Four main intervention strategies for combating zinc deficiency include dietary modification/diversification, supplementation, fortification, and bio-fortification. The choice of each method depends on the availability of resources, technical feasibility, target group, and social acceptance. In this paper, we provide a review on zinc biochemical and physiological functions, metabolism including, absorption, excretion, and homeostasis, zinc bio-availability (inhibitors and enhancers, human requirement, groups at high-risk, consequences and causes of zinc deficiency, evaluation of zinc status, and prevention strategies of zinc deficiency.

  7. Zinc fingers as protein recognition motifs: Structural basis for the GATA-1/Friend of GATA interaction

    OpenAIRE

    Liew, Chu Kong; Simpson, Raina J. Y.; Kwan, Ann H.Y.; Crofts, Linda A.; Loughlin, Fionna E.; Matthews, Jacqueline M; Crossley, Merlin; Mackay, Joel P.

    2005-01-01

    GATA-1 and friend of GATA (FOG) are zinc-finger transcription factors that physically interact to play essential roles in erythroid and megakaryocytic development. Several naturally occurring mutations in the GATA-1 gene that alter the FOG-binding domain have been reported. The mutations are associated with familial anemias and thrombocytopenias of differing severity. To elucidate the molecular basis for the GATA-1/FOG interaction, we have determined the three-dimensional structure of a compl...

  8. The Nuts and Bolts of Zinc-Nickel: OEM Zinc Nickel Implementation on Fasteners - Getting It Into Production

    Science.gov (United States)

    2014-11-01

    Blake Simpson Louie Tran The Nuts and Bolts of Zinc- Nickel OEM Zinc Nickel Implementation on Fasteners – Getting It Into Production Report...REPORT TYPE 3. DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE The Nuts and Bolts of Zinc- Nickel : OEM Zinc Nickel Implementation on...currently in production 2. Problem at Hand – Hexavalent Chromates 3. Transition to Zinc- Nickel 4. Preliminary Testing 5. Plan moving forward for

  9. Sealed Cylindrical Silver/Zinc Batteries Project

    Data.gov (United States)

    National Aeronautics and Space Administration — RBC Technologies has significanly improved the cycle life and wet life of silver/zinc battery technology through novel separator and anode formulations. This...

  10. Zinc-induced protection against cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Early, J.L.; Schnell, R.C.

    1978-02-01

    Pretreatment of male rats with cadmium acetate potentiates the duration of hexobarbital hypnosis and inhibits the rate of hepatic microsomal drug metabolism. Pretreatment of rats with zinc acetate protects against these alterations in drug action elicited by cadmium.

  11. Role of zinc in plasma membrane function

    National Research Council Canada - National Science Library

    O'Dell, B L

    2000-01-01

    ... with a posttranslational change in plasma membrane proteins. Among the signs of zinc deficiency in rats is a bleeding tendency associated with failure of platelet aggregation, a phenomenon that correlates with impaired uptake of Ca(2+) when stimulated...

  12. Controlling fires in silver/zinc batteries

    Science.gov (United States)

    Boshers, W. A.; Britz, W. A.

    1977-01-01

    Silver/zinc storage battery fires are often difficult to extinguish. Improved technique employs manifold connected to central evacuation chamber to rapidly vent combustion-supporting gases generated by battery plate oxides.

  13. A preliminary identification of insect successive wave in Egypt on control and zinc phosphide-intoxicated animals in different seasons

    Directory of Open Access Journals (Sweden)

    Marah Mohammad Abd El-Bar

    2016-09-01

    Full Text Available The presented study aimed primarily to document a baseline data of the decay process of rabbits and guinea pigs and their associated arthropod fauna, which are placed in an urban city: El Abbassyia, Cairo Governorate, Egypt, during winter and summer seasons, and to compare these data with the corresponding figure for zinc phosphide-intoxicated carrions. Generally, control rabbits and control guinea pigs were faster in their decay comparing the corresponding figure of the zinc phosphide–intoxicated group. A delay in colonization of insects was noticed either in the winter season for both groups, or additionally for the zinc phosphide groups. The associated insect fauna was represented in 6 orders, 20 families, and 36 genera and species. Necrophagous arthropods that supported decomposition of carcasses were mainly of orders Diptera and Coleoptera. Calliphoridae was the first insect family that colonized the different carcasses. The mean numbers of control immature dipterous maggots and similarly, the control coleopteran larvae significantly exceeded the corresponding mean numbers for the zinc phosphide-intoxicated groups in both winter and summer seasons in either rabbits or guinea pig groups. Moreover, the mean numbers of dipterous maggots or coleopteran larvae of rabbits significantly surpassed the corresponding figures for guinea pigs in both seasons. This study may add as a reference for the succession wave arthropod fauna in Cairo Governorate in winter and summer seasons. Moreover, it is the first record of the arthropod successive wave on zinc phosphide–intoxicated remains.

  14. Zinc coordination spheres in protein structures.

    Science.gov (United States)

    Laitaoja, Mikko; Valjakka, Jarkko; Jänis, Janne

    2013-10-07

    Zinc metalloproteins are one of the most abundant and structurally diverse proteins in nature. In these proteins, the Zn(II) ion possesses a multifunctional role as it stabilizes the fold of small zinc fingers, catalyzes essential reactions in enzymes of all six classes, or assists in the formation of biological oligomers. Previously, a number of database surveys have been conducted on zinc proteins to gain broader insights into their rich coordination chemistry. However, many of these surveys suffer from severe flaws and misinterpretations or are otherwise limited. To provide a more comprehensive, up-to-date picture on zinc coordination environments in proteins, zinc containing protein structures deposited in the Protein Data Bank (PDB) were analyzed in detail. A statistical analysis in terms of zinc coordinating amino acids, metal-to-ligand bond lengths, coordination number, and structural classification was performed, revealing coordination spheres from classical tetrahedral cysteine/histidine binding sites to more complex binuclear sites with carboxylated lysine residues. According to the results, coordination spheres of hundreds of crystal structures in the PDB could be misinterpreted due to symmetry-related molecules or missing electron densities for ligands. The analysis also revealed increasing average metal-to-ligand bond length as a function of crystallographic resolution, which should be taken into account when interrogating metal ion binding sites. Moreover, one-third of the zinc ions present in crystal structures are artifacts, merely aiding crystal formation and packing with no biological significance. Our analysis provides solid evidence that a minimal stable zinc coordination sphere is made up by four ligands and adopts a tetrahedral coordination geometry.

  15. A biokinetic model for zinc for use in radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Leggett, R.W., E-mail: rwl@ornl.gov

    2012-03-15

    The physiology of the essential trace element zinc has been studied extensively in human subjects using kinetic analysis of time-dependent measurements of administered zinc tracers. A number of biokinetic models describing zinc exchange between plasma and tissues and endogenous excretion of zinc have been derived as fits to data for specific study groups. More rudimentary biokinetic models for zinc have been developed to estimate radiation doses from internally deposited radioisotopes of zinc. The latter models are designed to provide broadly accurate estimates of cumulative decays of zinc radioisotopes in tissues and are not intended as realistic descriptions of the directions of movement of zinc in the body. This paper reviews biokinetic data for zinc and proposes a physiologically meaningful biokinetic model for systemic zinc for use in radiation protection. The proposed model bears some resemblance to zinc models developed in physiological studies but depicts a finer division of systemic zinc and is based on a broader spectrum of data than previous models. The proposed model and the model for zinc currently recommended by the International Commission on Radiological Protection yield reasonably similar estimates of total-body retention and effective dose for internally deposited radioisotopes of zinc but much different systemic distributions of activity and much different dose estimates for some individual tissues, particularly the liver. - Highlights: Black-Right-Pointing-Pointer Zinc is an essential trace element with numerous functions in the human body. Black-Right-Pointing-Pointer Several biokinetic models for zinc have been developed from tracer studies on humans. Black-Right-Pointing-Pointer More rudimentary biokinetic models for zinc have been developed in radiation protection. Black-Right-Pointing-Pointer Biokinetic data for zinc are reviewed and a new biokinetic model is proposed for radiation protection. Black-Right-Pointing-Pointer The proposed model

  16. Sensors an introductory course

    CERN Document Server

    Kalantar-zadeh, Kourosh

    2013-01-01

    Sensors: An Introductory Course provides an essential reference on the fundamentals of sensors. The book is designed to help readers in developing skills and the understanding required in order to implement a wide range of sensors that are commonly used in our daily lives. This book covers the basic concepts in the sensors field, including definitions and terminologies. The physical sensing effects are described, and devices which utilize these effects are presented. The most frequently used organic and inorganic sensors are introduced and the techniques for implementing them are discussed. This book: Provides a comprehensive representation of the most common sensors and can be used as a reference in relevant fields Presents learning materials in a concise and easy to understand manner Includes examples of how sensors are incorporated in real life measurements Contains detailed figures and schematics to assist in understanding the sensor performance Sensors: An Introductory Course is ideal for university stu...

  17. Smart Sensor Systems

    Science.gov (United States)

    Hunter, G. W.; Stetter, J. R.; Hesketh, P. J.; Liu, C. C.

    Sensors and sensor systems are vital to our awareness of our surroundings and provide safety, security, and surveillance, as well as enable monitoring of our health and environment. A transformative advance in the field of sensor technology has been the development of "Smart Sensor Systems". The definition of a Smart Sensor may vary, but typically at a minimum a Smart Sensor is the combination of a sensing element with processing capabilities provided by a microprocessor. That is, Smart Sensors are basic sensing elements with embedded intelligence. The sensor signal is fed to the microprocessor, which processes the data and provides an informative output to an external user. A more expansive view of a Smart Sensor System, which is used in this article, is illustrated in Fig. 19.1: a complete self-contained sensor system that includes the capabilities for logging, processing with a model of sensor response and other data, self-contained power, and an ability to transmit or display informative data to an outside user. The fundamental idea of a smart sensor is that the integration of silicon microprocessors with sensor technology cannot only provide interpretive power and customized outputs, but also significantly improve sensor system performance and capabilities.

  18. Ubiquitous Sensor Network for Chemical Sensors

    Institute of Scientific and Technical Information of China (English)

    Wan-Young Chung; Risto Myllylae

    2006-01-01

    Wireless sensor networks have been identified as one of the most important technologies for the 21st century. Recent advances in micro sensor fabrication technology and wireless communication technology enable the practical deployment of large-scale, low-power, inexpensive sensor networks. Such an approach offers an advantage over traditional sensing methods in many ways: large-scale, dense deployment not only extends spatial coverage and achieves higher resolution, but also increases the system's fault-tolerance and robustness. Moreover, the ad-hoc nature of wireless sensor networks makes them even more attractive for military and other risk-associated applications, such as environmental observation and habitat monitoring.

  19. Secondary structure and zinc ligation of human recombinant short-form stromelysin by multidimensional heteronuclear NMR.

    Science.gov (United States)

    Gooley, P R; Johnson, B A; Marcy, A I; Cuca, G C; Salowe, S P; Hagmann, W K; Esser, C K; Springer, J P

    1993-12-07

    Stromelysin-1, a member of the matrix metalloendoprotease family, is a zinc protease involved in the degradation of connective tissue in the extracellular matrix. As a step toward determining the structure of this protein, multidimensional heteronuclear NMR experiments have been applied to an inhibited truncated form of human stromelysin-1. Extensive 1H, 13C, and 15N sequential assignments have been obtained with a combination of three- and four-dimensional experiments. On the basis of sequential and short-range NOEs and 13C alpha chemical shifts, two helices have been delineated, spanning residues Asp-111 to Val-127 and Leu-195 to Ser-206. A third helix spanning residues Asp-238 to Gly-247 is characterized by sequential NOEs and 13C alpha chemical shifts, but not short-range NOEs. The lack of the latter NOEs suggests that this helix is either distorted or mobile. Similarly, sequential and interstrand NOEs and 13C alpha chemical shifts characterize a four-stranded beta-sheet with three parallel strands (Arg-100 to Ile-101, Ile-142 to Ala-147, Asp-177 to Asp-181) and one antiparallel strand (Ala-165 to Tyr-168). Two zinc sites have been identified in stromelysin [Salowe et al. (1992) Biochemistry 31, 4535-4540]. The NMR spectral properties, including chemical shift, pH dependence, and proton coupling of the imidazole nitrogens of six histidine residues (151, 166, 179, 201, 205, and 211), invariant in the matrix metalloendoprotease family, suggest that these residues are zinc ligands. NOE data indicate that these histidines form two clusters: one ligates the catalytic zinc (His-201, -205, and -211), and the other ligates a structural zinc (His-151, -166, and -179). Heteronuclear multiple quantum correlated spectra and specific labeling experiments indicate His-151, -179, -201, -205, and -211 are in the N delta 1H tautomer and His-166 is in the N epsilon 2H tautomer.

  20. Minimal motif peptide structure of metzincin clan zinc peptidases in micelles.

    Science.gov (United States)

    Onoda, Akira; Suzuki, Takako; Ishizuka, Hiroaki; Sugiyama, Rumiko; Ariyasu, Shinya; Yamamura, Takeshi

    2009-12-01

    It is well known that the functions of metalloproteins generally originate from their metal-binding motifs. However, the intrinsic nature of individual motifs remains unknown, particularly the details about metal-binding effects on the folding of motifs; the converse is also unknown, although there is no doubt that the motif is the core of the reactivity for each metalloprotein. In this study, we focused our attention on the zinc-binding motif of the metzincin clan family, HEXXHXXGXXH; this family contains the general zinc-binding sequence His-Glu-Xaa-Xaa-His (HEXXH) and the extended GXXH region. We adopted the motif sequence of stromelysin-1 and investigated the folding properties of the Trp-labeled peptides WAHEIAHSLGLFHA (STR-W1), AWHEIAHSLGLFHA (STR-W2), AHEIAHSLGWFHA (STR-W11), and AHEIAHSLGLFHWA (STR-W14) in the presence and absence of zinc ions in hydrophobic micellar environments by circular dichroism (CD) measurements. We accessed successful incorporation of these zinc peptides into micelles using quenching of Trp fluorescence. Results of CD studies indicated that two of the Trp-incorporated peptides, STR-W1 and STR-W14, exhibited helical folding in the hydrophobic region of cetyltrimethylammonium chloride micelle. The NMR structural analysis of the apo STR-W14 revealed that the conformation in the C-terminus GXXH region significantly differred between the apo state in the micelle and the reported Zn-bound state of stromelysin-1 in crystal structures. The structural analyses of the qualitative Zn-binding properties of this motif peptide provide an interesting Zn-binding mechanism: the minimum consensus motif in the metzincin clan, a basic zinc-binding motif with an extended GXXH region, has the potential to serve as a preorganized Zn binding scaffold in a hydrophobic environment.

  1. Amyloid precursor-like protein 1 (APLP1) exhibits stronger zinc-dependent neuronal adhesion than amyloid precursor protein and APLP2.

    Science.gov (United States)

    Mayer, Magnus C; Schauenburg, Linda; Thompson-Steckel, Greta; Dunsing, Valentin; Kaden, Daniela; Voigt, Philipp; Schaefer, Michael; Chiantia, Salvatore; Kennedy, Timothy E; Multhaup, Gerhard

    2016-04-01

    The amyloid precursor protein (APP) and its paralogs, amyloid precursor-like protein 1 (APLP1) and APLP2, are metalloproteins with a putative role both in synaptogenesis and in maintaining synapse structure. Here, we studied the effect of zinc on membrane localization, adhesion, and secretase cleavage of APP, APLP1, and APLP2 in cell culture and rat neurons. For this, we employed live-cell microscopy techniques, a microcontact printing adhesion assay and ELISA for protein detection in cell culture supernatants. We report that zinc induces the multimerization of proteins of the amyloid precursor protein family and enriches them at cellular adhesion sites. Thus, zinc facilitates the formation of de novo APP and APLP1 containing adhesion complexes, whereas it does not have such influence on APLP2. Furthermore, zinc-binding prevented cleavage of APP and APLPs by extracellular secretases. In conclusion, the complexation of zinc modulates neuronal functions of APP and APLPs by (i) regulating formation of adhesion complexes, most prominently for APLP1, and (ii) by reducing the concentrations of neurotrophic soluble APP/APLP ectodomains. Earlier studies suggest a function of the amyloid precursor protein (APP) family proteins in neuronal adhesion. We report here that adhesive function of these proteins is tightly regulated by zinc, most prominently for amyloid precursor-like protein 1 (APLP1). Zinc-mediated APLP1 multimerization, which induced formation of new neuronal contacts and decreased APLP1 shedding. This suggests that APLP1 could function as a zinc receptor processing zinc signals to stabilized or new neuronal contacts.

  2. Relationship between gastric levels and antiulcerogenic activity of zinc.

    Science.gov (United States)

    Navarro, C; Ramis, A; Sendrós, S; Bulbena, O; Ferrer, L; Escolar, G

    1990-01-01

    The relationship between the absorption of an organic zinc salt, zinc acexamate, and its antiulcerogenic activity in a model of cold-restraint stress was studied. Serum and gastric levels of zinc, as well as its antiulcerogenic effect, were determined after oral or intravenous administration of zinc acexamate. Cytochemical and X-ray microanalysis techniques were also applied. In the rats subjected to cold-restraint stress, gastric levels of zinc correlated with the antiulcerogenic effect observed after administration of zinc acexamate. However, it was not possible to establish a relationship between serum levels and the pharmacologic effect of zinc. Our results in animals subjected to regular diet indicate that the antiulcerogenic effect exhibited by zinc compounds could be associated with the presence of zinc at different levels of gastric tissue.

  3. A biokinetic model for zinc for use in radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Leggett, Richard Wayne [ORNL

    2012-01-01

    The physiology of the essential trace element zinc has been studied extensively in human subjects using kinetic analysis of time-dependent measurements of administered zinc tracers. A number of biokinetic models describing zinc exchange between plasma and tissues and loss of systemic zinc in excreta have been developed from the derived data. More rudimentary biokinetic models for zinc have been developed to estimate radiation doses from internally deposited radioisotopes of zinc. The latter models are designed to provide broadly accurate estimates of cumulative decays of zinc radioisotopes in tissues and are not intended as realistic descriptions of the directions of movement of zinc in the body. This paper reviews biokinetic data for zinc and proposes a physiologically meaningful biokinetic model for systemic zinc for use in radiation protection. The proposed model bears some resemblance to zinc models developed in physiological studies but depicts a finer division of systemic zinc and is based on a broader spectrum of data than previous models. The proposed model and current radiation protection model for zinc yield broadly similar estimates of effective dose from internally deposited radioisotopes of zinc but substantially different dose estimates for several individual tissues, particularly the liver.

  4. Serum and semen zinc levels in normozoospermic and oligozoospermic men

    Energy Technology Data Exchange (ETDEWEB)

    Madding, C.I.; Jacob, M.; Ramsay, V.P.; Sokol, R.Z.

    1986-01-01

    We studied 11 unselected men who presented to a Reproductive Endocrinology Clinic with histories of infertility and low sperm counts. Reproductive hormones and semen und serum zinc levels were measured. All men had semen analyses performed on at least three separate occasions. A similar set of laboratory evaluations were performed on 11 other men who had normal semen analyses and no history of infertility. No abnormalities of reproductive hormones were found in either group. Mean serum zinc levels were significantly lower in the infertile men. Mean semen zinc levels were not significantly different. There was no correlation between serum and semen zinc levels in either group. A significant correlation was found between sperm count and semen zinc in the volunteers with normal counts, but not in the oligozoospermic men. The results obtained in this study suggest that lowered serum zinc is more common than formerly appreciated in unselected patients with infertility. The high level of zinc found in semen is due primarily to the secretions of the prostate gland and reflects prostatic stores. Serum zinc is thought to be a reasonable indicator of zinc status. The lack of correlation between serum zinc and semen zinc found in our study suggests that mild zinc deficiency may lower serum zinc while the larger prostatic zinc stores remain unaffected.

  5. Zinc and Regulation of Inflammatory Cytokines: Implications for Cardiometabolic Disease

    Directory of Open Access Journals (Sweden)

    Samir Samman

    2012-07-01

    Full Text Available In atherosclerosis and diabetes mellitus, the concomitant presence of low-grade systemic inflammation and mild zinc deficiency highlights a role for zinc nutrition in the management of chronic disease. This review aims to evaluate the literature that reports on the interactions of zinc and cytokines. In humans, inflammatory cytokines have been shown both to up- and down-regulate the expression of specific cellular zinc transporters in response to an increased demand for zinc in inflammatory conditions. The acute phase response includes a rapid decline in the plasma zinc concentration as a result of the redistribution of zinc into cellular compartments. Zinc deficiency influences the generation of cytokines, including IL-1β, IL-2, IL-6, and TNF-α, and in response to zinc supplementation plasma cytokines exhibit a dose-dependent response. The mechanism of action may reflect the ability of zinc to either induce or inhibit the activation of NF-κB. Confounders in understanding the zinc-cytokine relationship on the basis of in vitro experimentation include methodological issues such as the cell type and the means of activating cells in culture. Impaired zinc homeostasis and chronic inflammation feature prominently in a number of cardiometabolic diseases. Given the high prevalence of zinc deficiency and chronic disease globally, the interplay of zinc and inflammation warrants further examination.

  6. Advances in intracellular DNA sensors of PYHIN family and mechanisms of viral evasion of innate immune responses%DNA 识别受体 PYHIN 家族及相关病毒免疫逃逸机制的研究

    Institute of Scientific and Technical Information of China (English)

    魏巍; 汪速飞; 倪明; 余冰

    2016-01-01

    宿主细胞内的DNA识别受体可识别病毒核酸分子并激活细胞天然免疫反应,从而产生抗病毒效应;同时,病毒也进化出相应机制来逃避或抑制这种免疫反应。本文总结了宿主细胞内 DNA识别受体PYHIN家族识别病毒核酸并激活细胞天然免疫反应的特点和分子机制,并讨论了病毒逃避宿主天然免疫应答的方式。%The intracellular DNA sensors in host cells recognize viral nucleic acid and activate the innate immunity , then resulting in antiviral effects . However , the viral pathogens have also evolved with appropriate strategies to evade or suppress the innate immune responses .In this review ,the characteristics and molecular mechanisms of the immune effects of PYHIN family ,one of the DNA sensors in host cells that could recognize viral DNA and activate innate immunity are discussed .The strategies of how viruses escape from the immune surveillance are also summarized .

  7. Inactivation of respiratory syncytial virus by zinc finger reactive compounds.

    Science.gov (United States)

    Boukhvalova, Marina S; Prince, Gregory A; Blanco, Jorge C G

    2010-01-26

    Infectivity of retroviruses such as HIV-1 and MuLV can be abrogated by compounds targeting zinc finger motif in viral nucleocapsid protein (NC), involved in controlling the processivity of reverse transcription and virus infectivity. Although a member of a different viral family (Pneumoviridae), respiratory syncytial virus (RSV) contains a zinc finger protein M2-1 also involved in control of viral polymerase processivity. Given the functional similarity between the two proteins, it was possible that zinc finger-reactive compounds inactivating retroviruses would have a similar effect against RSV by targeting RSV M2-1 protein. Moreover, inactivation of RSV through modification of an internal protein could yield a safer whole virus vaccine than that produced by RSV inactivation with formalin which modifies surface proteins. Three compounds were evaluated for their ability to reduce RSV infectivity: 2,2'-dithiodipyridine (AT-2), tetraethylthiuram disulfide and tetramethylthiuram disulfide. All three were capable of inactivating RSV, with AT-2 being the most potent. The mechanism of action of AT-2 was analyzed and it was found that AT-2 treatment indeed results in the modification of RSV M2-1. Altered intramolecular disulfide bond formation in M2-1 protein of AT-2-treated RSV virions might have been responsible for abrogation of RSV infectivity. AT-2-inactivated RSV was found to be moderately immunogenic in the cotton rats S.hispidus and did not cause a vaccine-enhancement seen in animals vaccinated with formalin-inactivated RSV. Increasing immunogenicity of AT-2-inactivated RSV by adjuvant (Ribi), however, led to vaccine-enhanced disease. This work presents evidence that compounds that inactivate retroviruses by targeting the zinc finger motif in their nucleocapsid proteins are also effective against RSV. AT-2-inactivated RSV vaccine is not strongly immunogenic in the absence of adjuvants. In the adjuvanted form, however, vaccine induces immunopathologic response. The

  8. Inactivation of respiratory syncytial virus by zinc finger reactive compounds

    Directory of Open Access Journals (Sweden)

    Prince Gregory A

    2010-01-01

    Full Text Available Abstract Background Infectivity of retroviruses such as HIV-1 and MuLV can be abrogated by compounds targeting zinc finger motif in viral nucleocapsid protein (NC, involved in controlling the processivity of reverse transcription and virus infectivity. Although a member of a different viral family (Pneumoviridae, respiratory syncytial virus (RSV contains a zinc finger protein M2-1 also involved in control of viral polymerase processivity. Given the functional similarity between the two proteins, it was possible that zinc finger-reactive compounds inactivating retroviruses would have a similar effect against RSV by targeting RSV M2-1 protein. Moreover, inactivation of RSV through modification of an internal protein could yield a safer whole virus vaccine than that produced by RSV inactivation with formalin which modifies surface proteins. Results Three compounds were evaluated for their ability to reduce RSV infectivity: 2,2'-dithiodipyridine (AT-2, tetraethylthiuram disulfide and tetramethylthiuram disulfide. All three were capable of inactivating RSV, with AT-2 being the most potent. The mechanism of action of AT-2 was analyzed and it was found that AT-2 treatment indeed results in the modification of RSV M2-1. Altered intramolecular disulfide bond formation in M2-1 protein of AT-2-treated RSV virions might have been responsible for abrogation of RSV infectivity. AT-2-inactivated RSV was found to be moderately immunogenic in the cotton rats S.hispidus and did not cause a vaccine-enhancement seen in animals vaccinated with formalin-inactivated RSV. Increasing immunogenicity of AT-2-inactivated RSV by adjuvant (Ribi, however, led to vaccine-enhanced disease. Conclusions This work presents evidence that compounds that inactivate retroviruses by targeting the zinc finger motif in their nucleocapsid proteins are also effective against RSV. AT-2-inactivated RSV vaccine is not strongly immunogenic in the absence of adjuvants. In the adjuvanted form

  9. Family Polymorphism

    DEFF Research Database (Denmark)

    Ernst, Erik

    2001-01-01

    safety and flexibility at the level of multi-object systems. We are granted the flexibility of using different families of kinds of objects, and we are guaranteed the safety of the combination. This paper highlights the inability of traditional polymorphism to handle multiple objects, and presents family...... polymorphism as a way to overcome this problem. Family polymorphism has been implemented in the programming language gbeta, a generalized version of Beta, and the source code of this implementation is available under GPL....

  10. My Family

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Everyone has a family.We live in it and feel very warm.There are three persons in my family,my mother,father and I.We live together very happily and there are many interesting stories about my family. My father is a hard-working man.He works as a doctor.He always tries his best to help every,patient and make patients comfortable.But sonetimes he works so hard

  11. Family Polymorphism

    DEFF Research Database (Denmark)

    Ernst, Erik

    2001-01-01

    safety and flexibility at the level of multi-object systems. We are granted the flexibility of using different families of kinds of objects, and we are guaranteed the safety of the combination. This paper highlights the inability of traditional polymorphism to handle multiple objects, and presents family...... polymorphism as a way to overcome this problem. Family polymorphism has been implemented in the programming language gbeta, a generalized version of Beta, and the source code of this implementation is available under GPL....

  12. Microwave Synthesis of Zinc Hydroxy Sulfate Nanoplates and Zinc Oxide Nanorods in the Classroom

    Science.gov (United States)

    Dziedzic, Rafal M.; Gillian-Daniel, Anne Lynn; Peterson, Greta M.; Martínez-Herna´ndez, Kermin J.

    2014-01-01

    In this hands-on, inquiry-based lab, high school and undergraduate students learn about nanotechnology by synthesizing their own nanoparticles in a single class period. This simple synthesis of zinc oxide nanorods and zinc hydroxy sulfate nanoplates can be done in 15 min using a household microwave oven. Reagent concentration, reaction…

  13. Possible role of zinc in diminishing lead-related occupational stress-a zinc nutrition concern.

    Science.gov (United States)

    Wani, Ab Latif; Ahmad, Ajaz; Shadab, G G H A; Usmani, Jawed Ahmad

    2017-03-01

    Lead and zinc are mostly present at the same occupational source and usually found as co-contaminants. Lead is known to associate with detrimental effects to humans. Zinc however is an essential nutrient and its deficiency causes debilitating effects on growth and development. Besides, it acts as core ion of important enzymes and proteins. The purpose of this study was to examine if zinc concentrations are associated with blood lead levels and if zinc may prevent lead-induced DNA damage. Blood samples were collected from 92 workers as participants occupationally exposed to lead or lead and zinc and 38 comparison participants having no history of such exposure. Lead and zinc levels were determined from blood by atomic absorption spectrophotometry and genetic damage was assessed by comet assay. Correlation was calculated by Spearman's rho. Lead concentrations were observed to increase among workers with increase in years of exposure. There was a significant difference (p lead levels between workers and controls. In addition, significant difference (p lead, while as the inverse effect of zinc on DNA damage. The results suggest that zinc may influence body lead absorption and may have a role in preventing the genetic damage caused by lead.

  14. Effect of zinc from zinc sulfate on trace mineral concentrations of milk in Varamini ewes

    NARCIS (Netherlands)

    Zali, A.; Ganjkhanlou, M.

    2009-01-01

    This study was conducted to evaluate the effect of feeding supplemental zinc (zinc sulfate) in different levels (15, 30, or 45 mg/kg) on trace mineral concentrations in milk of ewes. Thirty lactating Varaminni ewes were assigned to three experimental groups according to their live body weights, milk

  15. Enhanced zinc consumption causes memory deficits and increased brain levels of zinc

    Science.gov (United States)

    Flinn, J.M.; Hunter, D.; Linkous, D.H.; Lanzirotti, A.; Smith, L.N.; Brightwell, J.; Jones, B.F.

    2005-01-01

    Zinc deficiency has been shown to impair cognitive functioning, but little work has been done on the effects of elevated zinc. This research examined the effect on memory of raising Sprague-Dawley rats on enhanced levels of zinc (10 ppm ZnCO3; 0.153 mM) in the drinking water for periods of 3 or 9 months, both pre- and postnatally. Controls were raised on lab water. Memory was tested in a series of Morris Water Maze (MWM) experiments, and zinc-treated rats were found to have impairments in both reference and working memory. They were significantly slower to find a stationary platform and showed greater thigmotaxicity, a measure of anxiety. On a working memory task, where the platform was moved each day, zinc-treated animals had longer latencies over both trials and days, swam further from the platform, and showed greater thigmotaxicity. On trials using an Atlantis platform, which remained in one place but was lowered on probe trials, the zinc-treated animals had significantly fewer platform crossings, spent less time in the target quadrant, and did not swim as close to the platform position. They had significantly greater latency on nonprobe trials. Microprobe synchrotron X-ray fluorescence (??SXRF) confirmed that brain zinc levels were increased by adding ZnCO 3 to the drinking water. These data show that long-term dietary administration of zinc can lead to impairments in cognitive function. ?? 2004 Elsevier Inc. All rights reserved.

  16. Bioavailability of zinc in Wistar rats fed with rice fortified with zinc oxide.

    Science.gov (United States)

    Della Lucia, Ceres Mattos; Santos, Laura Luiza Menezes; Rodrigues, Kellen Cristina da Cruz; Rodrigues, Vivian Cristina da Cruz; Martino, Hércia Stampini Duarte; Sant'Ana, Helena Maria Pinheiro

    2014-06-13

    The study of zinc bioavailability in foods is important because this mineral intake does not meet the recommended doses for some population groups. Also, the presence of dietary factors that reduce zinc absorption contributes to its deficiency. Rice fortified with micronutrients (Ultra Rice®) is a viable alternative for fortification since this cereal is already inserted into the population habit. The aim of this study was to evaluate the bioavailability of zinc (Zn) in rice fortified with zinc oxide. During 42 days, rats were divided into four groups and fed with diets containing two different sources of Zn (test diet: UR® fortified with zinc oxide, or control diet: zinc carbonate (ZnCO3)), supplying 50% or 100%, respectively, of the recommendations of this mineral for animals. Weight gain, food intake, feed efficiency ratio, weight, thickness and length of femur; retention of zinc, calcium (Ca) and magnesium (Mg) in the femur and the concentrations of Zn in femur, plasma and erythrocytes were evaluated. Control diet showed higher weight gain, feed efficiency ratio, retention of Zn and Zn concentration in the femur (p 0.05) for dietary intake, length and thickness of the femur, erythrocyte and plasmatic Zn between groups. Although rice fortified with zinc oxide showed a lower bioavailability compared to ZnCO3, this food can be a viable alternative to be used as a vehicle for fortification.

  17. Bioinformatics Analysis of Zinc Transporter from Baoding Alfalfa

    Institute of Scientific and Technical Information of China (English)

    Haibo WANG; Junyun GUO

    2012-01-01

    [Objective] This study aimed to perform the bioinformatics analysis of Zinc transporter (ZnT) from Baoding Alfalfa. [Method] Based on the amino acid sequence, the physical and chemical properties, hydrophilicity/hydrophobicity, secondary structure of ZnT from Baoding alfalfa were predicted by a series of bioinformatics software. And the transmembrane domains were predicted by using different online tools. [Result] ZnT is a hydrophobic protein containing 408 amino acids with the theoretical pl of 5.94, and it has 7 potential transmembrane hydrophobic regions. In the sec- ondary structure, co-helix (Hh) accounted for 48.04%, extended strand (Ee) for 9.56%, random coil (Cc) for 42.40%, which was accored with the characteristic of transmembrane protein. [Conclusion] mZnT is a member of CDF family, responsible for transporting Zn^2+ out of the cell membrane to reduce the concentration and toxicity of Zn^2+.

  18. Family literacy

    DEFF Research Database (Denmark)

    Sehested, Caroline

    2012-01-01

    I Projekt familielæsning, der er et samarbejde mellem Nationalt Videncenter for Læsning og Hillerød Bibliotek, arbejder vi med at få kontakt til de familier, som biblioteket ellers aldrig ser som brugere og dermed også de børn, der vokser op i familier, for hvem bøger og oplæsningssituationer ikke...... er en selvfølgelig del af barndommen. Det, vi vil undersøge og ønsker at være med til at udvikle hos disse familier, er det, man kan kalde family literacy....

  19. CMOS Imaging Sensor Technology for Aerial Mapping Cameras

    Science.gov (United States)

    Neumann, Klaus; Welzenbach, Martin; Timm, Martin

    2016-06-01

    In June 2015 Leica Geosystems launched the first large format aerial mapping camera using CMOS sensor technology, the Leica DMC III. This paper describes the motivation to change from CCD sensor technology to CMOS for the development of this new aerial mapping camera. In 2002 the DMC first generation was developed by Z/I Imaging. It was the first large format digital frame sensor designed for mapping applications. In 2009 Z/I Imaging designed the DMC II which was the first digital aerial mapping camera using a single ultra large CCD sensor to avoid stitching of smaller CCDs. The DMC III is now the third generation of large format frame sensor developed by Z/I Imaging and Leica Geosystems for the DMC camera family. It is an evolution of the DMC II using the same system design with one large monolithic PAN sensor and four multi spectral camera heads for R,G, B and NIR. For the first time a 391 Megapixel large CMOS sensor had been used as PAN chromatic sensor, which is an industry record. Along with CMOS technology goes a range of technical benefits. The dynamic range of the CMOS sensor is approx. twice the range of a comparable CCD sensor and the signal to noise ratio is significantly better than with CCDs. Finally results from the first DMC III customer installations and test flights will be presented and compared with other CCD based aerial sensors.

  20. Growth of zinc oxide nanostructures

    Indian Academy of Sciences (India)

    K Sreenivas; Sanjeev Kumar; Jaya Choudhury; Vinay Gupta

    2005-11-01

    Zinc oxide (ZnO) nanowhiskers have been prepared using a multilayer ZnO(50 nm)/Zn(20 nm)/ZnO(2 m) structure on a polished stainless steel (SS) substrate by high rate magnetron sputtering. The formation of uniformly distributed ZnO nanowhiskers with about 20 nm dia. and 2 to 5 m length was observed after a post-deposition annealing of the prepared structure at 300–400 ° C. An array of highly -axis oriented ZnO columns (70–300 nm in dia. and up to 10 m long) were grown on Si substrates by pulsed laser deposition (PLD) at a high pressure (1 Torr), and Raman studies showed the activation of surface phonon modes. The nanosized powder (15–20 nm) and nanoparticle ZnO films on glass substrate were also prepared by a chemical route. Nanowhiskers showed enhanced UV light detection characteristics, and the chemically prepared ZnO nanoparticle films exhibited good sensing properties for alcohol.

  1. Nanoscale zinc silicate from phytoliths

    Science.gov (United States)

    Qadri, S. B.; Gorzkowski, E. P.; Rath, B. B.; Feng, C. R.; Amarasinghe, R.; Freitas, J. A.; Culbertson, J. C.; Wollmershauser, J. A.

    2017-10-01

    We report a faster, less expensive method of producing zinc silicate nanoparticles. Such particles are used in high volume to make phosphors and anti-corrosion coatings. The approach makes use of phytoliths (plant rocks), which are microscopic, amorphous, and largely silicate particles embedded in plants, that lend themselves to being easily broken down into nanoparticles. Nanoparticles of Zn2SiO4 were produced in a two stage process. In the refinement stage, plant residue, mixed with an appropriate amount of ZnO, was heated in an argon atmosphere to a temperature exceeding 1400 °C for four to six hours and then heated in air at 650 °C to remove excess carbon. TEM shows 50-100 nm nanoparticles. Raman scattering indicates that only the -Zn2SiO4 crystalline phase was present. X-ray analysis indicated pure rhombohedral R 3 bar phase results from using rice/wheat husks. Both samples luminesced predominantly at 523 nm when illuminated with X-rays or UV laser light.

  2. The binding of zinc ions to Emericella nidulans endo-β-1,4-galactanase is essential for crystal formation

    DEFF Research Database (Denmark)

    Otten, Harm; Michalak, Malwina; Mikkelsen, Jørn Dalgaard

    2013-01-01

    A novel Emericella nidulans endo-β-1,4-galactanase (EnGAL) demonstrates a strong capacity to generate high levels of very potent prebiotic oligosaccharides from potato pulp, a by-product of the agricultural potato-starch industry. EnGAL belongs to glycoside hydrolase family 53 and shows high (72...... belonging to GH53. It also revealed 15 zinc ions bound to the protein, one of which is located in the active site, where it is coordinated by residues Glu136 and Glu246 which comprise the catalytic machinery. The majority of the zinc ions are located on the surface of the enzyme, in some cases with side...

  3. A new zinc binding fold underlines the versatility of zinc binding modules in protein evolution.

    Science.gov (United States)

    Sharpe, Belinda K; Matthews, Jacqueline M; Kwan, Ann H Y; Newton, Anthea; Gell, David A; Crossley, Merlin; Mackay, Joel P

    2002-05-01

    Many different zinc binding modules have been identified. Their abundance and variety suggests that the formation of zinc binding folds might be relatively common. We have determined the structure of CH1(1), a 27-residue peptide derived from the first cysteine/histidine-rich region (CH1) of CREB binding protein (CBP). This peptide forms a highly ordered zinc-dependent fold that is distinct from known folds. The structure differs from a subsequently determined structure of a larger region from the CH3 region of CBP, and the CH1(1) fold probably represents a nonphysiologically active form. Despite this, the fold is thermostable and tolerant to both multiple alanine mutations and changes in the zinc-ligand spacing. Our data support the idea that zinc binding domains may arise frequently. Additionally, such structures may prove useful as scaffolds for protein design, given their stability and robustness.

  4. Photochemistry of flavoprotein light sensors.

    Science.gov (United States)

    Conrad, Karen S; Manahan, Craig C; Crane, Brian R

    2014-10-01

    Three major classes of flavin photosensors, light oxygen voltage (LOV) domains, blue light sensor using FAD (BLUF) proteins and cryptochromes (CRYs), regulate diverse biological activities in response to blue light. Recent studies of structure, spectroscopy and chemical mechanism have provided unprecedented insight into how each family operates at the molecular level. In general, the photoexcitation of the flavin cofactor leads to changes in redox and protonation states that ultimately remodel protein conformation and molecular interactions. For LOV domains, issues remain regarding early photochemical events, but common themes in conformational propagation have emerged across a diverse family of proteins. For BLUF proteins, photoinduced electron transfer reactions critical to light conversion are defined, but the subsequent rearrangement of hydrogen bonding networks key for signaling remains highly controversial. For CRYs, the relevant photocycles are actively debated, but mechanistic and functional studies are converging. Despite these challenges, our current understanding has enabled the engineering of flavoprotein photosensors for control of signaling processes within cells.

  5. Low serum zinc level in dpression

    Directory of Open Access Journals (Sweden)

    SA Mousavi

    2006-07-01

    Full Text Available BACKGROUND: Major Depressive Disorder (MDD is a common disorder, with a lifetime prevalence of about 15 percent, perhaps as high as 25 percent for women. The etiology of MDD is too complex to be explained totally by a single social, developmental, or biological theory. A variety of factors appear to work together to cause or precipitate depressive disorders. Various functions have been reported for trace elements such as zink in recovery or exacerbation of depression. METHODS: In this experimental study, we studied 46 patients with MDD based on DSM IV criteria, among the patients referred to mental disorders clininc of Noor Hospital. Twenty Patients were men and 26 were women. Thirty two volunteers of general population were evaluated for depression with Beck depression test who did not show any depressive symptoms with this test. A blood sample of 5cc was obtained from each person and the serum zinc concentration was measured. Data gathered and analyzed with SPSS, logistic regression and chi-squar tests. RESULTS: Serum zinc concentrations were 74 to 130 mg/dl in men and 60 to 128 mg/dl in women of control group. Serum zinc concentration was 30 to 60 mg/dl in depressive patients that it was lower in women than men. The difference between serum zinc concentrations of normal and depressive persons was meaningful (P = 0.02. CONCLUSION: In our study, the serum concentration of zinc was about half of normal value. This study replicates previous findings that major depressed subjects show significantly lowered serum zinc concentration. KEYWORDS: Depression, zinc.

  6. Zinc, copper and selenium in reproduction.

    Science.gov (United States)

    Bedwal, R S; Bahuguna, A

    1994-07-15

    Of the nine biological trace elements, zinc, copper and selenium are important in reproduction in males and females. Zinc content is high in the adult testis, and the prostate has a higher concentration of zinc than any other organ of the body. Zinc deficiency first impairs angiotensin converting enzyme (ACE) activity, and this in turn leads to depletion of testosterone and inhibition of spermatogenesis. Defects in spermatozoa are frequently observed in the zinc-deficient rat. Zinc is thought to help to extend the functional life span of the ejaculated spermatozoa. Zinc deficiency in the female can lead to such problems as impaired synthesis/secretion of (FSH) and (LH), abnormal ovarian development, disruption of the estrous cycle, frequent abortion, a prolonged gestation period, teratogenicity, stillbirths, difficulty in parturition, pre-eclampsia, toxemia and low birth weights of infants. The level of testosterone in the male has been suggested to play a role in the severity of copper deficiency. Copper-deficient female rats are protected against mortality due to copper deficiency, and the protection has been suggested to be provided by estrogens, since estrogens alter the subcellular distribution of copper in the liver and increase plasma copper levels by inducing ceruloplasmin synthesis. The selenium content of male gonads increases during pubertal maturation. Selenium is localized in the mitochondrial capsule protein (MCP) of the midpiece. Maximal incorporation in MCP occurs at steps 7 and 12 of spermatogenesis and uptake decreases by step 15. Selenium deficiency in females results in infertility, abortions and retention of the placenta. The newborns from a selenium-deficient mother suffer from muscular weakness, but the concentration of selenium during pregnancy does not have any effect on the weight of the baby or length of pregnancy. The selenium requirements of a pregnant and lactating mother are increased as a result of selenium transport to the fetus via

  7. Embedded sensor systems

    CERN Document Server

    Agrawal, Dharma Prakash

    2017-01-01

    This inspiring textbook provides an introduction to wireless technologies for sensors, explores potential use of sensors for numerous applications, and utilizes probability theory and mathematical methods as a means of embedding sensors in system design. It discusses the need for synchronization and underlying limitations, inter-relation between given coverage and connectivity to number of sensors needed, and the use of geometrical distance to determine location of the base station for data collection and explore use of anchor nodes for relative position determination of sensors. The book explores energy conservation, communication using TCP, the need for clustering and data aggregation, and residual energy determination and energy harvesting. It covers key topics of sensor communication like mobile base stations and relay nodes, delay-tolerant sensor networks, and remote sensing and possible applications. The book defines routing methods and do performance evaluation for random and regular sensor topology an...

  8. Towards Sensor Database Systems

    DEFF Research Database (Denmark)

    Bonnet, Philippe; Gehrke, Johannes; Seshadri, Praveen

    2001-01-01

    Sensor networks are being widely deployed for measurement, detection and surveillance applications. In these new applications, users issue long-running queries over a combination of stored data and sensor data. Most existing applications rely on a centralized system for collecting sensor data....... These systems lack flexibility because data is extracted in a predefined way; also, they do not scale to a large number of devices because large volumes of raw data are transferred regardless of the queries that are submitted. In our new concept of sensor database system, queries dictate which data is extracted...... from the sensors. In this paper, we define the concept of sensor databases mixing stored data represented as relations and sensor data represented as time series. Each long-running query formulated over a sensor database defines a persistent view, which is maintained during a given time interval. We...

  9. Air Sensor Toolbox

    Science.gov (United States)

    Air Sensor Toolbox provides information to citizen scientists, researchers and developers interested in learning more about new lower-cost compact air sensor technologies and tools for measuring air quality.

  10. Zinc Fortification Decreases ZIP1 Gene Expression of Some Adolescent Females with Appropriate Plasma Zinc Levels

    Directory of Open Access Journals (Sweden)

    Rosa O. Méndez

    2014-06-01

    Full Text Available Zinc homeostasis is achieved after intake variation by changes in the expression levels of zinc transporters. The aim of this study was to evaluate dietary intake (by 24-h recall, absorption, plasma zinc (by absorption spectrophotometry and the expression levels (by quantitative PCR, of the transporters ZIP1 (zinc importer and ZnT1 (zinc exporter in peripheral white blood cells from 24 adolescent girls before and after drinking zinc-fortified milk for 27 day. Zinc intake increased (p < 0.001 from 10.5 ± 3.9 mg/day to 17.6 ± 4.4 mg/day, and its estimated absorption from 3.1 ± 1.2 to 5.3 ± 1.3 mg/day. Mean plasma zinc concentration remained unchanged (p > 0.05 near 150 µg/dL, but increased by 31 µg/dL (p < 0.05 for 6/24 adolescents (group A and decreased by 25 µg/dL (p < 0.05 for other 6/24 adolescents (group B. Expression of ZIP1 in blood leukocytes was reduced 1.4-fold (p < 0.006 in group A, while for the expression of ZnT1 there was no difference after intervention (p = 0.39. An increase of dietary zinc after 27-days consumption of fortified-milk did not increase (p > 0.05 the plasma level of adolescent girls but for 6/24 participants from group A in spite of the formerly appropriation, which cellular zinc uptake decreased as assessed by reduction of the expression of ZIP1.

  11. Specific and ultrasensitive ciprofloxacin detection by responsive photonic crystal sensor

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Rong; Wang, Yong [Department of Chemistry, School of Science, Tianjin University, Tianjin 300072 (China); Yu, Li-Ping, E-mail: lipingyu@tju.edu.cn [Department of Chemistry, School of Science, Tianjin University, Tianjin 300072 (China); State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071 (China)

    2014-09-15

    Highlights: • Sensor was designed by integrating complexes into responsive photonic crystal. • Ternary tryptophan–zinc(II)–ciprofloxacin complexes were chosen for sensing. • Excellent sensing of ciprofloxacin was achieved in aqueous media. - Abstract: A new approach for specific and ultrasensitive measurement of ciprofloxacin has been developed by integrating ternary complexes into responsive photonic crystal (RPC). Tryptophan was first immobilized within the polyacrylamide hydrogel substrates of RPC. The determination of ciprofloxacin was via the existence of zinc(II) ions that function as a ‘bridge’ to form specific tryptophan–zinc(II)–ciprofloxacin complexes step by step, which resulted in a stepwise red-shift of the diffraction wavelength. A maximum wavelength shift from 798 to 870 nm for ciprofloxacin was observed when the RPC film was immersed in 10{sup −4} M ciprofloxacin. A linear relationship has been obtained between the Δλ of diffraction peak and logarithm of ciprofloxacin concentration at pH 5.0 in the range of 10{sup −10} to 10{sup −4} M. And the least detectable concentration in present work is about 5 × 10{sup −11} M. The results demonstrated that the as-designed ternary complexes-based RPC sensor exhibited high sensitivity, satisfactory specificity and excellent recoverability for sensing of ciprofloxacin in aqueous media and were validated by detecting ciprofloxacin in the eye-drop sample.

  12. Effect of low zinc intake on absorption and excretion of zinc by infants studied with 70Zn as extrinsic tag.

    Science.gov (United States)

    Ziegler, E E; Serfass, R E; Nelson, S E; Figueroa-Colón, R; Edwards, B B; Houk, R S; Thompson, J J

    1989-11-01

    The effect of low dietary intake of zinc was studied in six normal infants with the use of 70Zn as an extrinsic tag. Of the two study formulas, one provided a zinc intake similar to that of customary infant formulas ("high" intake), whereas the other provided a "low" zinc intake. Two zinc absorption studies were performed with each formula (sequence: high-low-low-high). Extrinsically labeled formula was fed for 24 h and excreta were collected for 72 h. Zinc isotope ratios were determined by inductively coupled plasma mass spectrometry (ICP/MS). When zinc intake was high, net zinc absorption was 9.1 +/- 8.7% (mean +/- SD) of intake and net zinc retention was 74 +/- 91 micrograms/(kg.d). True zinc (70Zn) absorption was 16.8 +/- 5.8% of intake and fecal excretion of endogenous zinc was 78 +/- 56 micrograms/(kg.d). When zinc intake was low, net absorption of zinc increased significantly (P less than 0.001) to 26.0 +/- 13.0% of intake, but net retention was not significantly different at 42 +/- 33 micrograms/(kg.d). True absorption of zinc also increased significantly (P less than 0.001) to 41.1 +/- 7.8% of intake, whereas fecal endogenous zinc decreased (P less than 0.05) to 34 +/- 16 micrograms/(kg.d) during low zinc intake. Thus, infants maintain zinc balance in the face of low zinc intake through increased efficiency of absorption and decreased excretion of endogenous zinc.

  13. Charge transport in dye-sensibilized porous zinc oxide films; Ladungstransport in farbstoffsensibilisierten poroesen Zinkoxidfilmen

    Energy Technology Data Exchange (ETDEWEB)

    Reemts, J.

    2006-05-18

    During the last decades, zinc oxide has attracted a lot of attention as an important material in various electrical, chemical, and optical applications. In the present work results are discussed gained from investigations of highly porous electrochemically deposited zinc oxide, which is a promising electrode material both in the area of solar energy conversion and sensor technology. The films were prepared by adding detergents during the electrodeposition process. The detergents have a structure-directing influence during the film deposition and, therefore, on the morphology of the films. The obtained electrodes can easily be sensitized for light or different chemicals by a simple adsorption of different molecules. In the present work I discuss the fundamental charge transport properties of electrochemically deposited zinc oxide films. Temperature-dependent measurements of the current-voltage characteristics are carried out and the spectral response of the photoconductivity is investigated. In order to understand the charge transport properties of this highly porous material, it is necessary to get a deeper insight in the electrode morphology. Therefore, different optical and scanning probe microscopy methods are used to characterize the inner structure of the electrodes. The electrical conductivity of the zinc oxide films can be seen as a thermally activated process, which can be explained by electronic transitions from the valence band of the zinc oxide to two shallow impurity levels. The current-voltage characteristic unveils a nonlinear behavior which can be explained by a space-charge-limited current model with traps distributed in energy. Upon excitation with different wavelengths, the conductivity of the zinc oxide increases already under sub-band gap illumination due to widely distributed trap states within the band gap. The transients of the photoconductivity follow a stretched exponential law with time scales in the range of several hours, either if the

  14. Digital Sensor Technology

    Energy Technology Data Exchange (ETDEWEB)

    Ted Quinn; Jerry Mauck; Richard Bockhorst; Ken Thomas

    2013-07-01

    The nuclear industry has been slow to incorporate digital sensor technology into nuclear plant designs due to concerns with digital qualification issues. However, the benefits of digital sensor technology for nuclear plant instrumentation are substantial in terms of accuracy, reliability, availability, and maintainability. This report demonstrates these benefits in direct comparisons of digital and analog sensor applications. It also addresses the qualification issues that must be addressed in the application of digital sensor technology.

  15. Fiber optic geophysical sensors

    Science.gov (United States)

    Homuth, Emil F.

    1991-01-01

    A fiber optic geophysical sensor in which laser light is passed through a sensor interferometer in contact with a geophysical event, and a reference interferometer not in contact with the geophysical event but in the same general environment as the sensor interferometer. In one embodiment, a single tunable laser provides the laser light. In another embodiment, separate tunable lasers are used for the sensor and reference interferometers. The invention can find such uses as monitoring for earthquakes, and the weighing of objects.

  16. Extreme Velocity Wind Sensor

    Science.gov (United States)

    Perotti, Jose; Voska, Ned (Technical Monitor)

    2002-01-01

    This presentation provides an overview of the development of new hurricane wind sensor (Extreme Velocity Wind Sensor) for the Kennedy Space Center (KSC) which is designed to withstand winds of up to three hundred miles an hour. The proposed Extreme Velocity Wind Sensor contains no moveable components that would be exposed to extreme wind conditions. Topics covered include: need for new hurricane wind sensor, conceptual design, software applications, computational fluid dynamic simulations of design concept, preliminary performance tests, and project status.

  17. Comparison of serum levels of copper and zinc among multiple sclerosis patients and control group.

    Directory of Open Access Journals (Sweden)

    Behnaz Sedighi

    2013-12-01

    Full Text Available There have been several studies done on the role of metals in the occurrence of multiple sclerosis (MS disease, but their roles have not been confirmed yet. Because of the lack of information on this issue, this study compared the serum level of copper and zinc in MS patients with their levels in a control group.This was an analytical, cross-sectional study conducted in Kerman (a medium size city, Iran. We assessed the serum level of copper and zinc in 58 MS patients and 39 healthy individuals, who were selected from the relatives of cases and matched for age and sex.The average serum level of Copper in cases and controls were 93.7 and 88.9 ml/dl, respectively. The corresponding numbers for Zinc were 36.7 and 40.9 ml/dl, respectively. There was no significant difference between the two groups (copper: P = 0.459; zinc: P = 0.249.The groups were matched for age, sex, and family. However, we did not find a considerable difference between the level of these metals in MS patients and controls.

  18. Structural insights of ZIP4 extracellular domain critical for optimal zinc transport

    Science.gov (United States)

    Zhang, Tuo; Sui, Dexin; Hu, Jian

    2016-06-01

    The ZIP zinc transporter family is responsible for zinc uptake from the extracellular milieu or intracellular vesicles. The LIV-1 subfamily, containing nine out of the 14 human ZIP proteins, is featured with a large extracellular domain (ECD). The critical role of the ECD is manifested by disease-causing mutations on ZIP4, a representative LIV-1 protein. Here we report the first crystal structure of a mammalian ZIP4-ECD, which reveals two structurally independent subdomains and an unprecedented dimer centred at the signature PAL motif. Structure-guided mutagenesis, cell-based zinc uptake assays and mapping of the disease-causing mutations indicate that the two subdomains play pivotal but distinct roles and that the bridging region connecting them is particularly important for ZIP4 function. These findings lead to working hypotheses on how ZIP4-ECD exerts critical functions in zinc transport. The conserved dimeric architecture in ZIP4-ECD is also demonstrated to be a common structural feature among the LIV-1 proteins.

  19. [Acceleration of somatic development in the surroundings of zinc plant].

    Science.gov (United States)

    Torbus, Onufry; Grzywna, Teresa; Grzywna, Ewa

    2002-01-01

    One of the most sensitive measures of health state depending on for example social conditions of the society and family as well as the degree of environmental pollution is somatic development of children. Changes in the somatic and descriptive values, which have been observed for the decades, are known as secular trend that is tendency for changes over centuries. One of its parts is enlargement of parameters of somatic development that is acceleration. Numerous studies on the development of children living in Silesia, the area of great economic potential, however, highly polluted, show the deterioration of developmental parameters of children in Silesia in comparison with their peers from other parts of Poland. The aim of the study is to evaluate the acceleration of somatic development of children living nearby zinc plant. Studies on the somatic development of children at the age between 7-15 years attending the same primary school were carried out in Miasteczko Slaskie at interval of 15 years (1983-1998). Miasteczko Slaskie is the town known for its zinc plant that emits the highest levels of pollution of all steelworks in Poland. This is related to metallurgy of non-ferrous metals. The results were compared with the results of body measurement of the peers from one of the schools in Tarnowskie Góry carried out in the years 1988 and 1998. It was shown that boys and girls from both communities presented lower body mass and height in all periods of study than the standards of The Institute of Mother and Child showed in 1983. No acceleration of somatic development was present among children in Tarnowskie Góry, which may be explained by deterioration of social conditions of these children. However, this acceleration is present in the population of children in Miasteczko Slaskie. This fact may be explained by significantly decreased emission of pollution by the zinc plant and intense care for children shown by the plant managers as well as the foundation for children

  20. Small Families

    Science.gov (United States)

    ... easier for both parents to combine careers with family life. The general stress level is lower because there often are fewer ... can help replace the missing ties. For many families, religious congregational ... such as youth and neighborhood activity centers also can fulfill these ...

  1. FAMILY PLATYSTOMATIDAE.

    Science.gov (United States)

    Wendt, Lisiane Dilli

    2016-06-14

    Platystomatidae (Signal Flies) are one of the largest families of Tephritoidea, with about 1200 species and four subfamilies, worldwide distributed. However, Platystomatidae are not well represented in the New World, and in the Neotropical Region only four genera and 26 species, belonging to Platystomatinae, are recorded. The family is a group understudied in Colombia and only one species is recorded to the country.

  2. Role of nutritional zinc in the prevention of osteoporosis.

    Science.gov (United States)

    Yamaguchi, Masayoshi

    2010-05-01

    Zinc is known as an essential nutritional factor in the growth of the human and animals. Bone growth retardation is a common finding in various conditions associated with dietary zinc deficiency. Bone zinc content has been shown to decrease in aging, skeletal unloading, and postmenopausal conditions, suggesting its role in bone disorder. Zinc has been demonstrated to have a stimulatory effect on osteoblastic bone formation and mineralization; the metal directly activates aminoacyl-tRNA synthetase, a rate-limiting enzyme at translational process of protein synthesis, in the cells, and it stimulates cellular protein synthesis. Zinc has been shown to stimulate gene expression of the transcription factors runt-related transcription factor 2 (Runx2) that is related to differentiation into osteoblastic cells. Moreover, zinc has been shown to inhibit osteoclastic bone resorption due to inhibiting osteoclast-like cell formation from bone marrow cells and stimulating apoptotic cell death of mature osteoclasts. Zinc has a suppressive effect on the receptor activator of nuclear factor (NF)-kappaB ligand (RANKL)-induced osteoclastogenesis. Zinc transporter has been shown to express in osteoblastic and osteoclastic cells. Zinc protein is involved in transcription. The intake of dietary zinc causes an increase in bone mass. beta-Alanyl-L: -histidinato zinc (AHZ) is a zinc compound, in which zinc is chelated to beta-alanyl-L: -histidine. The stimulatory effect of AHZ on bone formation is more intensive than that of zinc sulfate. Zinc acexamate has also been shown to have a potent-anabolic effect on bone. The oral administration of AHZ or zinc acexamate has the restorative effect on bone loss under various pathophysiologic conditions including aging, skeletal unloading, aluminum bone toxicity, calcium- and vitamin D-deficiency, adjuvant arthritis, estrogen deficiency, diabetes, and fracture healing. Zinc compounds may be designed as new supplementation factor in the prevention and

  3. Mechanisms of mammalian zinc-regulated gene expression.

    Science.gov (United States)

    Jackson, Kelly A; Valentine, Ruth A; Coneyworth, Lisa J; Mathers, John C; Ford, Dianne

    2008-12-01

    Mechanisms through which gene expression is regulated by zinc are central to cellular zinc homoeostasis. In this context, evidence for the involvement of zinc dyshomoeostasis in the aetiology of diseases, including Type 2 diabetes, Alzheimer's disease and cancer, highlights the importance of zinc-regulated gene expression. Mechanisms elucidated in bacteria and yeast provide examples of different possible modes of zinc-sensitive gene regulation, involving the zinc-regulated binding of transcriptional activators and repressors to gene promoter regions. A mammalian transcriptional regulatory mechanism that mediates zinc-induced transcriptional up-regulation, involving the transcription factor MTF1 (metal-response element-binding transcription factor 1), has been studied extensively. Gene responses in the opposite direction (reduced mRNA levels in response to increased zinc availability) have been observed in mammalian cells, but a specific transcriptional regulatory process responsible for such a response has yet to be identified. Examples of single zinc-sensitive transcription factors regulating gene expression in opposite directions are emerging. Although zinc-induced transcriptional repression by MTF1 is a possible explanation in some specific instances, such a mechanism cannot account for repression by zinc of all mammalian genes that show this mode of regulation, indicating the existence of as yet uncharacterized mechanisms of zinc-regulated transcription in mammalian cells. In addition, recent findings reveal a role for effects of zinc on mRNA stability in the regulation of specific zinc transporters. Our studies on the regulation of the human gene SLC30A5 (solute carrier 30A5), which codes for the zinc transporter ZnT5, have revealed that this gene provides a model system by which to study both zinc-induced transcriptional down-regulation and zinc-regulated mRNA stabilization.

  4. Apoptosis may underlie the pathology of zinc-deficient skin.

    Science.gov (United States)

    Wilson, Dallas; Varigos, George; Ackland, M Leigh

    2006-02-01

    The trace element zinc is essential for the survival and function of all cells. Zinc deficiency, whether nutritional or genetic, is fatal if left untreated. The effects of zinc deficiency are particularly obvious in the skin, seen as an erythematous rash, scaly plaques, and ulcers. Electron microscopy reveals degenerative changes within keratinocytes. Despite the well-documented association between zinc deficiency and skin pathology, it is not clear which cellular processes are most sensitive to zinc deficiency and could account for the typical pathological features. We used the cultured HaCaT keratinocyte line to obtain insight into the cellular effects of zinc deficiency, as these cells show many characteristics of normal skin keratinocytes. Zinc deficiency was induced by growing cells in the presence of the zinc chelator, TPEN, or by growth in zinc-deficient medium. Growth of cells in zinc-deficient medium resulted in a 44% reduction of intracellular zinc levels and a 75% reduction in the activity of the zinc-dependent enzyme, 5'-nucleotidase, relative to the control cells. Over a period of 7 days of exposure to zinc-deficient conditions, no changes in cell viability and growth, or in the cytoskeletal and cell adhesion systems, were found in HaCaT cells. At 7 days, however, induction of apoptosis was indicated by the presence of DNA fragmentation and expression of active caspase-3 in cells. These results demonstrate that apoptosis is the earliest detectable cellular change induced by zinc deficiency in HaCaT keratinocytes. Our observations account for many of the features of zinc deficiency, including the presence of degenerate nuclei, chromatin aggregates and abnormal organization of keratin, that may represent the later stages of apoptosis. In summary, a major causal role for apoptosis in the pathology of zinc deficiency in the skin is proposed. This role is consistent with the previously unexplained diverse range of degenerative cellular changes seen at the

  5. Different Zinc Sources Have Diverse Impacts on Gene Expression of Zinc Absorption Related Transporters in Intestinal Porcine Epithelial Cells.

    Science.gov (United States)

    Huang, Danping; Zhuo, Zhao; Fang, Shenglin; Yue, Min; Feng, Jie

    2016-10-01

    This study was conducted to investigate the effects of zinc sources on gene expression of zinc-related transporters in intestinal porcine epithelial cells (IPEC-1). IPEC-1 cells were treated with zinc glycine chelate (Zn-Gly), zinc methionine (Zn-Met), and zinc sulfate (ZnSO4), respectively, for measurement of cell viability. Then, the relative expression of zinc-related transporters in IPEC-1 in response to different zinc sources (50 μmol/L zinc) was measured. Zinc transporter SLC39A4 (ZIP4) expression was selectively silenced to assess the function of ZIP4 in inorganic and organic zinc absorption. The result showed that Zn-Gly and Zn-Met had lower cell damage compared with ZnSO4 on the same zinc levels. Different zinc sources improved the expression of metallothionein1 (MT1) and zinc transporter SLC30A1 (ZnT1) messenger RNA (mRNA) compared with the control (P zinc addition. MT1 and ZnT1 mRNA expressions in Zn-Gly and Zn-Met were higher than those in ZnSO4, and ZIP4 mRNA expression in Zn-Met was the lowest among three kinds of zinc sources (P zinc sources groups. Silencing of ZIP4 significantly decreased MT1 mRNA expression in ZnSO4 and Zn-Gly treatments, reduced zinc absorption rate, and increased DMT1 mRNA expression in ZnSO4 compared with negative control. In summary, different zinc sources could improve zinc status on IPEC-1 cells and organic zinc had lower cell damage compared with ZnSO4. Moreover, Zn-Gly and Zn-Met are more efficient on zinc absorption according to the expression of various zinc-related transporters MT1, ZIP4, ZnT1, and DMT1. ZIP4 played a direct role in inorganic zinc uptake, and the absorption of zinc in Zn-Gly depends on ZIP4 partly, while absorption of Zn-Met is less dependent on ZIP4.

  6. Thermal flow micro sensors

    NARCIS (Netherlands)

    Elwenspoek, M.

    1999-01-01

    A review is given on sensors fabricated by silicon micromachining technology using the thermal domain for the measurement of fluid flow. Attention is paid especially to performance and geometry of the sensors. Three basic types of thermal flow sensors are discussed: anemometers, calorimetric flow se

  7. Sensors for Entertainment

    Science.gov (United States)

    Lamberti, Fabrizio; Sanna, Andrea; Rokne, Jon

    2016-01-01

    Sensors are becoming ubiquitous in all areas of science, technology, and society. In this Special Issue on “Sensors for Entertainment”, developments in progress and the current state of application scenarios for sensors in the field of entertainment is explored. PMID:27428981

  8. Environmental Sensor Networks

    OpenAIRE

    Martinez, Kirk; Hart, Jane; Ong, Royan

    2004-01-01

    Sensor networks for the natural environment require an understanding of earth science, combined with sensor, communications and computer technology. We discuss the evolution from data logging to sensor networks, describe our research from a glacial environment and highlight future challenges in this field.

  9. Optical waveguide sensors

    NARCIS (Netherlands)

    Fluitman, J.; Popma, Th.

    1986-01-01

    An overview of the field of optical waveguide sensors is presented. Some emphasis is laid on the development of a single scheme under which the diversity of sensor principles can be arranged. First three types of sensors are distinguished: intrinsic, extrinsic and active. Next, two steps are disting

  10. Sensors and actuators, Twente

    NARCIS (Netherlands)

    Bergveld, P.

    1989-01-01

    This paper describes the organization and the research programme of the Sensor and Actuator (S&A) Research Unit of the University of Twente, Enschede, the Netherlands. It includes short descriptions of all present projects concerning: micromachined mechanical sensors and actuators, optical sensors,

  11. Automotive vehicle sensors

    Energy Technology Data Exchange (ETDEWEB)

    Sheen, S.H.; Raptis, A.C.; Moscynski, M.J.

    1995-09-01

    This report is an introduction to the field of automotive vehicle sensors. It contains a prototype data base for companies working in automotive vehicle sensors, as well as a prototype data base for automotive vehicle sensors. A market analysis is also included.

  12. Sensors for Entertainment

    Directory of Open Access Journals (Sweden)

    Fabrizio Lamberti

    2016-07-01

    Full Text Available Sensors are becoming ubiquitous in all areas of science, technology, and society. In this Special Issue on “Sensors for Entertainment”, developments in progress and the current state of application scenarios for sensors in the field of entertainment is explored.

  13. New chromate-free passivation treatments for zinc, zinc alloy, and zinc-containing coatings and surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C. J. E.; King, J. E.; Wright, D. G.; Erricker, S. L.; Wilcox, G.; Treacy, G.; Hovestad, A.; Woodhead, T.; Buckland, J.; Lindsey, L.; Eruli, M.; Koelewijn, H.; Shropshire, I. [Defence Evaluation and Research Agency, Farnborough, Hampshire (United Kingdom)

    2001-07-01

    Results of a series of experiments to develop chromate-free treatments which provide the same level of corrosion protection and promote adhesion of surface coatings and paint films are discussed. The initial phase of the project identified two different treatments which prompted the investigation of pH, temperature and immersion time, as part of the effort to optimize the processes. When subjected to accelerated corrosion tests, one of the two processes (the PTA process) compared favourably with conventional chromate filming when applied to electrodeposited zinc-nickel coatings. Further investigation revealed that the process also works effectively on brass and nickel substrates and provides an appropriate substrate for the application of lacquer. Development of an effective treatment for zinc coatings, particularly hot dip galvanized zinc, is in progress. This paper discusses the results of toxicological and environmental studies conducted in conjunction with the two processes and reviews lessons learned and opportunities for exploiting the findings. 5 refs., 6 tabs.

  14. Rotorwash wind sensor evaluation

    Science.gov (United States)

    Meyerhoff, Curtis L.; Lake, Robert E.; Gordge, Dennis N.

    1993-08-01

    This project's purpose was to assess and document the ability of the Qualimetrics, Inc. model 2132 wind sensor (a cup and vane type sensor) to measure a rotor wash flow field as compared to the TSI, Inc. model 204D ion beam deflection sensor. The tests concentrated on the sensor's ability to capture dynamic characteristics of a helicopter rotor wash flow field. The project was conducted from April to November 1992 and consisted of quantitative laboratory and field testing. The laboratory testing included 9.5 hours of wind tunnel test time, subjecting each sensor to three step input tests at velocities of 20 knots, 50 knots, and 80 knots. Field test data were collected during one hour of SH-60B helicopter hover time at heights of 15 and 25 feet above ground level at distances of 35 and 70 feet from the wind sensors. Aircraft gross weights ranged between 19,600 and 20,500 pounds. All field test data were obtained in ambient wind conditions of approximately 8 knots at 40 degrees relative to the aircraft nose, -40 feet pressure altitude in an ambient temperature of 85 F. Laboratory data analysis indicates the model 2132 cup and vane sensor's time constant values were significantly higher than those of the model 204D ion beam sensor and varied relative to wind tunnel velocity settings. This indicates the model 2132 sensor's ability to accurately capture oscillations in a dynamic flow field is significantly less than the model 204D sensor. The model 2132 sensor did detect periodic or pulsating velocity magnitudes, but failed to capture significant oscillations as compared to the model 204D sensor. Comparative analysis of all field test event data indicate the model 2132 sensor only detected frequencies below 1.5 Hz and only captured an average of 46 percent of the model 204D sensor's maximum amplitude pulse values that were below 1.5 Hz. The model 2132 sensor's inability to capture many of the maximum pulse amplitudes is evidence of the sensor's limited capability to

  15. Stunting prevalence, plasma zinc concentrations, and dietary zinc intakes in a nationally representative sample suggest a high risk of zinc deficiency among women and young children in Cameroon.

    Science.gov (United States)

    Engle-Stone, Reina; Ndjebayi, Alex O; Nankap, Martin; Killilea, David W; Brown, Kenneth H

    2014-03-01

    Before initiating a mass zinc fortification program, this study assessed the prevalence of and risk factors for low zinc status among Cameroonian women and children. In a nationally representative survey, we randomly selected 30 clusters in each of 3 strata (North, South, and Yaoundé/Douala) and 10 households per cluster, each with a woman aged 15-49 y and a child aged 12-59 mo (n = 1002 households). Twenty-four-hour dietary recalls (with duplicates in a subset) and anthropometric measurements were conducted, and non-fasting blood was collected to measure plasma zinc concentration (PZC) and markers of inflammation. PZC was adjusted for methodologic factors (time of collection and processing, and presence of inflammation). The prevalence of stunting was 33% (32% South; 46% North; 13% Yaoundé/Douala). Among women, 82% had low adjusted PZC (Nutrition Consultative Group (IZiNCG), 29 and 41% of women had inadequate zinc intakes, assuming moderate and low bioavailability, respectively, but only 8% of children had inadequate zinc intake. Depending on the estimated physiologic zinc requirement applied, 17% (IZiNCG) and 92% (Institute of Medicine) of women had inadequate absorbable zinc intakes. Total zinc intakes were greatest in the North region, possibly because of different dietary patterns in this area. Zinc deficiency is a public health problem among women and children in Cameroon, although PZC and dietary zinc yield different estimates of the prevalence of deficiency. Large-scale programs to improve zinc nutrition, including food fortification, are needed.

  16. Intraprostatic injection of neutralized zinc in rats

    Energy Technology Data Exchange (ETDEWEB)

    Fahim, M.S.; Wang, M.; Sutcu, M.F.; Fahim, Z.; Safron, J.A.; Ganjam, V.K. (Univ. of Missouri, Columbia (United States) Xian Medical University (China))

    1991-03-11

    Zinc has been implicated in steroid endocrinology of the prostate gland. The conversion of testosterone to dihydrotestosterone (DHT) by 5{alpha}-reductase enzyme is believed to express androgenic responses in the prostate. To note the effect of neutralized zinc on the prostate, 50 sexually mature rats, weighing 325 {plus minus} 20 grams, were divided into 5 groups as follows: (1) control, (2) sham, (3) castrated, (4) injected intraprostatically with 10 mg. neutralized zinc, and (5) injected intraprostatically with 20 mg. neutralized zinc. Results in the treated groups indicated significant reduction of prostate weights, 12% and 53% and histologically normal prostate; no significant change in weight and histological structure of testes, epididymides, and seminal vesicles; significant reduction in 5{alpha}-reductase activity and total protein and DNA concentrations in prostate tissue; and no significant effect on progeny of treated animals. These results suggest that direct application of neutralized zinc to the prostate offers a new modality for treatment of prostatitis without affecting spermatogenesis and testosterone production.

  17. Antioxidant role of zinc in diabetes mellitus.

    Science.gov (United States)

    Cruz, Kyria Jayanne Clímaco; de Oliveira, Ana Raquel Soares; Marreiro, Dilina do Nascimento

    2015-03-15

    Chronic hyperglycemia statue noticed in diabetes mellitus favors the manifestation of oxidative stress by increasing the production of reactive oxygen species and/or by reducing the antioxidant defense system activity. Zinc plays an important role in antioxidant defense in type 2 diabetic patients by notably acting as a cofactor of the superoxide dismutase enzyme, by modulating the glutathione metabolism and metallothionein expression, by competing with iron and copper in the cell membrane and by inhibiting nicotinamide adenine dinucleotide phosphate-oxidase enzyme. Zinc also improves the oxidative stress in these patients by reducing chronic hyperglycemia. It indeed promotes phosphorylation of insulin receptors by enhancing transport of glucose into cells. However, several studies reveal changes in zinc metabolism in individuals with type 2 diabetes mellitus and controversies remain regarding the effect of zinc supplementation in the improvement of oxidative stress in these patients. Faced with the serious challenge of the metabolic disorders related to oxidative stress in diabetes along with the importance of antioxidant nutrients in the control of this disease, new studies may contribute to improve our understanding of the role played by zinc against oxidative stress and its connection with type 2 diabetes mellitus prognosis. This could serve as a prelude to the development of prevention strategies and treatment of disorders associated with this chronic disease.

  18. Zinc Leaching from Tire Crumb Rubber

    Science.gov (United States)

    Rhodes, E. P.; Ren, J.; Mays, D. C.

    2010-12-01

    Recent estimates indicate that more than 2 billion scrap tires are currently stockpiled in the United States and approximately 280 million more tires are added annually. Various engineering applications utilize recycled tires in the form of shredded tire crumb rubber. However, the use of tire crumb rubber may have negative environmental impacts, especially when the rubber comes into contact with water. A review of the literature indicates that leaching of zinc from tire crumb rubber is the most significant water quality concern associated with using this material. Zinc is generally used in tire manufacturing, representing approximately 1.3% of the final product by mass. This study will report results from the U.S. Environmental Protection Agency’s (EPA’s) Synthetic Precipitation Leaching Procedure, batch leaching tests, and column leaching tests performed to quantify the process by which zinc leaches from tire crumb rubber into water. Results are interpreted with a first-order kinetic attachment/detachment model, implemented with the U.S. Agricultural Research Service software HYDRUS-1D, in order to determine the circumstances when zinc leaching from tire crumb rubber would be expected to comply with the applicable discharge limits. One potential application for recycled tires is replacing sand with tire crumb rubber in granular media filters used for stormwater pollution control. For this to be a viable application, the total zinc in the stormwater discharge must be below the EPA’s benchmark value of 0.117 mg/L.

  19. Relative Penetration of Zinc Oxide and Zinc Ions into Human Skin after Application of Different Zinc Oxide Formulations.

    Science.gov (United States)

    Holmes, Amy M; Song, Zhen; Moghimi, Hamid R; Roberts, Michael S

    2016-02-23

    Zinc oxide (ZnO) is frequently used in commercial sunscreen formulations to deliver their broad range of UV protection properties. Concern has been raised about the extent to which these ZnO particles (both micronized and nanoparticulate) penetrate the skin and their resultant toxicity. This work has explored the human epidermal skin penetration of zinc oxide and its labile zinc ion dissolution product that may potentially be formed after application of ZnO nanoparticles to human epidermis. Three ZnO nanoparticle formulations were used: a suspension in the oil, capric caprylic triglycerides (CCT), the base formulation commonly used in commercially available sunscreen products; an aqueous ZnO suspension at pH 6, similar to the natural skin surface pH; and an aqueous ZnO suspension at pH 9, a pH at which ZnO is stable and there is minimal pH-induced impairment of epidermal integrity. In each case, the ZnO in the formulations did not penetrate into the intact viable epidermis for any of the formulations but was associated with an enhanced increase in zinc ion fluorescence signal in both the stratum corneum and the viable epidermis. The highest labile zinc fluorescence was found for the ZnO suspension at pH 6. It is concluded that, while topically applied ZnO does not penetrate into the viable epidermis, these applications are associated with hydrolysis of ZnO on the skin surface, leading to an increase in zinc ion levels in the stratum corneum, thence in the viable epidermis and subsequently in the systemic circulation and the urine.

  20. Improving Reproducibility of Lab-on-a-Chip Sensor with Bismuth Working Electrode for Determining Zn in Serum by Anodic Stripping Voltammetry

    Science.gov (United States)

    Pei, Xing; Kang, Wenjing; Yue, Wei; Bange, Adam; Heineman, William R.; Papautsky, Ian

    2014-01-01

    This work reports on the continuing development of a lab-on-a-chip electrochemical sensor for determination of zinc in blood serum using square wave anodic stripping voltammetry. The microscale sensor consists of a three electrode system, including an environmentally friendly bismuth working electrode, an integrated silver/silver chloride reference electrode, and a gold auxiliary electrode. The sensor demonstrates a linear response in 0.1 M acetate buffer at pH 6 for zinc concentrations in the 1–30 μM range. By optimizing bismuth film deposition and better control of the fabrication process, repeatability of the sensor was improved, reducing variability from 42% to <2%. Through optimization of electrolyte and stripping voltammetry parameters, limit of detection was greatly improved to 60 nM. The optimized sensor was also able to measure zinc in the extracted blood serum. Ultimately, with integrated sample preparation, the sensor will permit rapid (min) measurements of zinc from a sub-mL sample (a few drops of blood) for clinical applications. PMID:24729629

  1. Ampoule failure sensor development for semiconductor crystal growth experiments

    Science.gov (United States)

    Watring, Dale A.; Johnson, Martin

    1994-01-01

    Currently there are no devices to detect an ampoule failure in semiconductor crystal growth experiments. If an ampoule fails, it will go undetected until the containing cartridge is breached due to chemical degradation. The experiment will then be terminated resulting in a failed experiment and a loss of data. The objective of this research was to develop a reliable failure sensor that would detect a specific liquid or vapor material before the metallic cartridge is degraded and the processing furnace contaminated. The sensor is a chemical fuse made from a metal with which the semiconductor material reacts more rapidly than it does with the containing cartridge. Upon ampoule failure, the sensor is exposed to the vapor or liquid semiconductor and the chemical reaction causes a resistance change in the sensor material. The sensor shows a step change in resistance on the order of megohms when exposed to mercury zinc telluride (HgZnTe), mercury cadmium telluride (HgCdTe), or gallium arsenide (GaAs). This ampoule failure sensor is being tested for possible use on the second United States Microgravity Mission (USML-2) and is the subject of a NASA patent application.

  2. Virtual Sensor Test Instrumentation

    Science.gov (United States)

    Wang, Roy

    2011-01-01

    Virtual Sensor Test Instrumentation is based on the concept of smart sensor technology for testing with intelligence needed to perform sell-diagnosis of health, and to participate in a hierarchy of health determination at sensor, process, and system levels. A virtual sensor test instrumentation consists of five elements: (1) a common sensor interface, (2) microprocessor, (3) wireless interface, (4) signal conditioning and ADC/DAC (analog-to-digital conversion/ digital-to-analog conversion), and (5) onboard EEPROM (electrically erasable programmable read-only memory) for metadata storage and executable software to create powerful, scalable, reconfigurable, and reliable embedded and distributed test instruments. In order to maximize the efficient data conversion through the smart sensor node, plug-and-play functionality is required to interface with traditional sensors to enhance their identity and capabilities for data processing and communications. Virtual sensor test instrumentation can be accessible wirelessly via a Network Capable Application Processor (NCAP) or a Smart Transducer Interlace Module (STIM) that may be managed under real-time rule engines for mission-critical applications. The transducer senses the physical quantity being measured and converts it into an electrical signal. The signal is fed to an A/D converter, and is ready for use by the processor to execute functional transformation based on the sensor characteristics stored in a Transducer Electronic Data Sheet (TEDS). Virtual sensor test instrumentation is built upon an open-system architecture with standardized protocol modules/stacks to interface with industry standards and commonly used software. One major benefit for deploying the virtual sensor test instrumentation is the ability, through a plug-and-play common interface, to convert raw sensor data in either analog or digital form, to an IEEE 1451 standard-based smart sensor, which has instructions to program sensors for a wide variety of

  3. Investigation of thiol derivatized gold nanoparticle sensors for gas analysis

    Science.gov (United States)

    Stephens, Jared S.

    Analysis of volatile organic compounds (VOCs) in air and exhaled breath by sensor array is a very useful testing technique. It can provide non-invasive, fast, inexpensive testing for many diseases. Breath analysis has been very successful in identifying cancer and other diseases by using a chemiresistor sensor or array with gold nanoparticles to detect biomarkers. Acetone is a biomarker for diabetes and having a portable testing device could help to monitor diabetic and therapeutic progress. An advantage to this testing method is it is conducted at room temperature instead of 200 degrees Celsius. 3. The objective of this research is to determine the effect of thiol derivatized gold nanoparticles based on sensor(s) detection of VOCs. The VOCs to be tested are acetone, ethanol, and a mixture of acetone and ethanol. Each chip is tested under all three VOCs and three concentration levels (0.1, 1, and 5.0 ppm). VOC samples are used to test the sensors' ability to detect and differentiate VOCs. Sensors (also referred to as a chip) are prepared using several types of thiol derivatized gold nanoparticles. The factors are: thiol compound and molar volume loading of the thiol in synthesis. The average resistance results are used to determine the VOC selectivity of the sensors tested. The results show a trend of increasing resistance as VOC concentration is increased relative to dry air; which is used as baseline for VOCs. Several sensors show a high selectivity to one or more VOCs. Overall the 57 micromoles of 4-methoxy-toluenethiol sensor shows the strongest selectivity for VOCs tested. 3. Gerfen, Kurt. 2012. Detection of Acetone in Air Using Silver Ion Exchanged ZSM-5 and Zinc Oxide Sensing Films. Master of Science thesis, University of Louisville.

  4. The changes of zinc transporter ZnT gene expression in response to zinc supplementation in obese women.

    Science.gov (United States)

    Noh, Hwayoung; Paik, Hee Young; Kim, Jihye; Chung, Jayong

    2014-12-01

    Obesity is associated with an alteration in zinc metabolism. This alteration may be associated with changes in gene expression of zinc transporters. In this study, we examined the leukocyte expression of zinc transporter ZnTs in response to zinc supplementation in young obese women. Thirty-five young obese women (BMI ≥ 25 kg/m(2)), aged 18-28 years, were randomly assigned to two groups: a placebo group or a zinc group (30 mg zinc/day for 8 weeks). Usual dietary zinc intake was estimated from 3-day diet records. Serum zinc and urinary zinc concentrations were measured by atomic absorption spectrometry. Messenger RNA (mRNA) levels of leukocyte ZnT transporters were examined using quantitative real-time PCR. Expression levels of two ZnT transporters, ZnT1 and ZnT5, in obese women, increased significantly after zinc supplementation. At the end of the study, mRNA levels of ZnT1 and ZnT5 showed no correlation with serum zinc or urinary zinc concentration in obese women. In addition, a further study was conducted to identify whether the association between the gene expression levels of leukocyte ZnT1 and ZnT5 and dietary zinc intake remained consistent in 216 healthy young adults aged 20-29 years. A positive correlation between ZnT1 and dietary zinc intake (r = 0.181, P = 0.089) was also observed in healthy men although the significance was marginal. Taken together, these results show that the gene expression levels of ZnT1 and ZnT5 may be changed by zinc intake, suggesting that zinc supplementation could potentially restore ZnT transporter expression in obese women with altered zinc metabolism.

  5. Properties of Zip4 accumulation during zinc deficiency and its usefulness to evaluate zinc status: a study of the effects of zinc deficiency during lactation.

    Science.gov (United States)

    Hashimoto, Ayako; Nakagawa, Miki; Tsujimura, Natsuki; Miyazaki, Shiho; Kizu, Kumiko; Goto, Tomoko; Komatsu, Yusuke; Matsunaga, Ayu; Shirakawa, Hitoshi; Narita, Hiroshi; Kambe, Taiho; Komai, Michio

    2016-03-01

    Systemic and cellular zinc homeostasis is elaborately controlled by ZIP and ZnT zinc transporters. Therefore, detailed characterization of their expression properties is of importance. Of these transporter proteins, Zip4 functions as the primarily important transporter to control systemic zinc homeostasis because of its indispensable function of zinc absorption in the small intestine. In this study, we closely investigated Zip4 protein accumulation in the rat small intestine in response to zinc status using an anti-Zip4 monoclonal antibody that we generated and contrasted this with the zinc-responsive activity of the membrane-bound alkaline phosphatase (ALP). We found that Zip4 accumulation is more rapid in response to zinc deficiency than previously thought. Accumulation increased in the jejunum as early as 1 day following a zinc-deficient diet. In the small intestine, Zip4 protein expression was higher in the jejunum than in the duodenum and was accompanied by reduction of ALP activity, suggesting that the jejunum can become zinc deficient more easily. Furthermore, by monitoring Zip4 accumulation levels and ALP activity in the duodenum and jejunum, we reasserted that zinc deficiency during lactation may transiently alter plasma glucose levels in the offspring in a sex-specific manner, without affecting homeostatic control of zinc metabolism. This confirms that zinc nutrition during lactation is extremely important for the health of the offspring. These results reveal that rapid Zip4 accumulation provides a significant conceptual advance in understanding the molecular basis of systemic zinc homeostatic control, and that properties of Zip4 protein accumulation are useful to evaluate zinc status closely.

  6. Effect of Zinc supplementation on the Management of Acute ...

    African Journals Online (AJOL)

    Effect of Zinc supplementation on the Management of Acute Diarrhoea in Young ... Incidence and prevalence of diarrhea were compared between the groups. ... Supplementing the treatment of acute watery diarrhea with Zinc in just 2 cases ...

  7. Vitamin A, zinc, iodine, anemia and Anthropometric Status of ...

    African Journals Online (AJOL)

    Acer01

    2012-04-02

    Apr 2, 2012 ... of vitamin A, zinc, iron, iodine deficiency and anaemia among underprivileged 2 – 10 ... Anthropometric data (weight and height measurements) and ... serum and hair zinc levels were reported among children in southern and ...

  8. The Zinc Transport Systems and Their Regulation in Pathogenic Fungi.

    Science.gov (United States)

    Jung, Won Hee

    2015-09-01

    Zinc is an essential micronutrient required for many enzymes that play essential roles in a cell. It was estimated that approximately 3% of the total cellular proteins are required for zinc for their functions. Zinc has long been considered as one of the key players in host-pathogen interactions. The host sequesters intracellular zinc by utilizing multiple cellular zinc importers and exporters as a means of nutritional immunity. To overcome extreme zinc limitation within the host environment, pathogenic microbes have successfully evolved a number of mechanisms to secure sufficient concentrations of zinc for their survival and pathogenesis. In this review, we briefly discuss the zinc uptake systems and their regulation in the model fungus Saccharomyces cerevisiae and in major human pathogenic fungi such as Aspergillus fumigatus, Candida albicans, and Cryptococcus gattii.

  9. Zinc, nitrogen and salinity interaction on agronomic traits and some ...

    African Journals Online (AJOL)

    use

    2011-11-23

    Nov 23, 2011 ... study the response of canola to different nitrogen and zinc fertilizer levels under two doses ... moderately calcareous, low in nitrogen, low in organic matter and alkaline in reaction ...... Effect of foliar application of zinc, selenium ...

  10. Effect of zinc treatment on intestinal motility in experimentally ...

    African Journals Online (AJOL)

    olayemitoyin

    meal and the mechanisms of action of zinc sulphate on motility were investigated. The effective ... The positive action of zinc in acute ..... of gastrointestinal motility by inhibiting acetylcholine ... activity in smooth muscle is initiated by a Ca2+-.

  11. The immune system and the impact of zinc during aging

    Directory of Open Access Journals (Sweden)

    Haase Hajo

    2009-06-01

    Full Text Available Abstract The trace element zinc is essential for the immune system, and zinc deficiency affects multiple aspects of innate and adaptive immunity. There are remarkable parallels in the immunological changes during aging and zinc deficiency, including a reduction in the activity of the thymus and thymic hormones, a shift of the T helper cell balance toward T helper type 2 cells, decreased response to vaccination, and impaired functions of innate immune cells. Many studies confirm a decline of zinc levels with age. Most of these studies do not classify the majority of elderly as zinc deficient, but even marginal zinc deprivation can affect immune function. Consequently, oral zinc supplementation demonstrates the potential to improve immunity and efficiently downregulates chronic inflammatory responses in the elderly. These data indicate that a wide prevalence of marginal zinc deficiency in elderly people may contribute to immunosenescence.

  12. Concentrations of plasma copper and zinc and blood selenium in ...

    African Journals Online (AJOL)

    Department of Human and Animal Physiology, University of Stellenbosch, Stellenbosch 7600, ... Concentrations of plasma copper and zinc as well as blood selenium were determined in single and twin lambs ... of zinc within the body; notably.

  13. Oral zinc and common childhood infections--An update.

    Science.gov (United States)

    Basnet, Sudha; Mathisen, Maria; Strand, Tor A

    2015-01-01

    Zinc is an essential micronutrient important for growth and for normal function of the immune system. Many children in developing countries have inadequate zinc nutrition. Routine zinc supplementation reduces the risk of respiratory infections and diarrhea, the two leading causes of morbidity and mortality in young children worldwide. In childhood diarrhea oral zinc also reduces illness duration and risk of persistent episodes. Oral zinc is therefore recommended for the treatment of acute diarrhea in young children. The results from the studies that have measured the therapeutic effect of zinc on acute respiratory infections, however, are conflicting. Moreover, the results of therapeutic zinc for childhood malaria also are so far not promising.This paper gives a brief outline of the current evidence from clinical trials on therapeutic effect of oral zinc on childhood respiratory infections, pneumonia and malaria and also of new evidence of the effect on serious bacterial illness in young infants.

  14. Multi-Sensor Architectures

    DEFF Research Database (Denmark)

    Hussain, Dil Muhammad Akbar; Ahmed, Zaki; Khan, M. Z.

    2012-01-01

    The use of multiple sensors typically requires the fusion of data from different type of sensors. The combined use of such a data has the potential to give an efficient, high quality and reliable estimation. Input data from different sensors allows the introduction of target attributes (target type......, size) into the association logic. This requires a more general association logic, in which both the physical position parameters and the target attributes can be used simultaneously. Although, the data fusion from a number of sensors could provide better and reliable estimation but abundance...... processing units for same type of multiple sensors, typically radar in our case....

  15. Multifuctional integrated sensors (MFISES).

    Energy Technology Data Exchange (ETDEWEB)

    Homeijer, Brian D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Roozeboom, Clifton [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-10-01

    Many emerging IoT applications require sensing of multiple physical and environmental parameters for: completeness of information, measurement validation, unexpected demands, improved performance. For example, a typical outdoor weather station measures temperature, humidity, barometric pressure, light intensity, rainfall, wind speed and direction. Existing sensor technologies do not directly address the demand for cost, size, and power reduction in multi-paramater sensing applications. Industry sensor manufacturers have developed integrated sensor systems for inertial measurements that combine accelerometers, gyroscopes, and magnetometers, but do not address environmental sensing functionality. In existing research literature, a technology gap exists between the functionality of MEMS sensors and the real world applications of the sensors systems.

  16. Anti-ulcer activity of a slow-release zinc complex, zinc monoglycerolate (Glyzinc).

    Science.gov (United States)

    Rainsford, K D; Whitehouse, M W

    1992-06-01

    A slow-release zinc complex, zinc monoglycerolate (ZMG) was examined for its potential gastroprotective activity in various gastric ulcer models. These models comprised (a) oral or parenteral non-steroidal anti-inflammatory drugs (NSAIDs) given to rats whose gastrointestinal mucosa was pre-sensitized by prior development of arthritis, oleyl alcohol-induced inflammation and cold exposure, (b) oral ethanol (12.5-100%) with and without added 4% HCl, (c) intraperitoneal reserpine (5 mg kg-1) in arthritic and normal rats and in normal mice, (d) oral NSAIDs given to mice in which acid and pepsin production was stimulated by co-administration of intraperitoneal bethanechol chloride (5 mg kg-1) to enhance ulcer development, and (e) NSAIDs given to carrageenan-inflamed rats to determine effects of ZMG on paw inflammation. In these models, ZMG given orally was effective in preventing development of gastric lesions, except with propionic acid NSAIDs; the effective doses being apparently dependent on the severity of the mucosal injury. In many of the models ZMG was superior to zinc sulphate and other zinc salts or metal ion complexes investigated but was slightly more effective or equipotent compared with zinc acexamate. ZMG did not impair the anti-oedemic effects of NSAIDs. ZMG is thus an effective agent in preventing ulcer development in a wide range of model systems and may be more effective than zinc salts because of the controlled slow-release of zinc from the complex.

  17. Nutritional assessment methods for zinc supplementation in prepubertal non-zinc-deficient children

    Directory of Open Access Journals (Sweden)

    Márcia Marília Gomes Dantas Lopes

    2015-10-01

    Full Text Available Background: Zinc is an essential nutrient that is required for numerous metabolic functions, and zinc deficiency results in growth retardation, cell-mediated immune dysfunction, and cognitive impairment. Objective: This study evaluated nutritional assessment methods for zinc supplementation in prepubertal non-zinc-deficient children. Design: We performed a randomised, controlled, triple-blind study. The children were divided into a control group (10% sorbitol, n=31 and an experimental group (10 mg Zn/day, n=31 for 3 months. Anthropometric and dietary assessments as well as bioelectrical measurements were performed in all children. Results: Our study showed (1 an increased body mass index for age and an increased phase angle in the experimental group; (2 a positive correlation between nutritional assessment parameters in both groups; (3 increased soft tissue, and mainly fat-free mass, in the body composition of the experimental group, as determined using bioelectrical impedance vector analysis; (4 increased consumption of all nutrients, including zinc, in the experimental group; and (5 an increased serum zinc concentration in both groups (p<0.0001. Conclusions: Given that a reference for body composition analysis does not exist for intervention studies, longitudinal studies are needed to investigate vector migration during zinc supplementation. These results reinforce the importance of employing multiple techniques to assess the nutritional status of populations.

  18. Selective extraction of zinc from sulfate leach solution of zinc ore

    Institute of Scientific and Technical Information of China (English)

    覃文庆; 蓝卓越; 黎维中; 邱冠周

    2003-01-01

    Selective extraction of zinc from sulfate leach solution of zinc ore was studied.D2EHPA dissolved in260# kerosene was used as extractant.The pH-extraction isotherms show the extraction order of D2EHPA for metals is Fe3+>Zn2+>Ca2+>Al3+>Mn2+>Cu2+>Cd2+>Co2+>Ni2+>Mg2+(pH0.5).This confirms that Fe3+ ispreferentially extracted before the extraction of zinc.Extraction experiments were carried out with varying the extractant content,equilibration time,aqueous pH and phase ratio,and the solvent extraction of zinc with sodium saltof D2EHPA were also investigated.Some impurity co-extracted into the zinc loaded organic phase was efficiently removed by scrub,and the Fe3+ was hardly stripped from organic phase by sulfuric acid,hence zinc was separatedfrom Fe3+ by selective stripping.A pregnant zinc sulfate solution with low contaminants was obtained by selectivesolvent extraction.

  19. Root-secreted nicotianamine from Arabidopsis halleri facilitates zinc hypertolerance by regulating zinc bioavailability.

    Science.gov (United States)

    Tsednee, Munkhtsetseg; Yang, Shun-Chung; Lee, Der-Chuen; Yeh, Kuo-Chen

    2014-10-01

    Hyperaccumulators tolerate and accumulate extraordinarily high concentrations of heavy metals. Content of the metal chelator nicotianamine (NA) in the root of zinc hyperaccumulator Arabidopsis halleri is elevated compared with nonhyperaccumulators, a trait that is considered to be one of the markers of a hyperaccumulator. Using metabolite-profiling analysis of root secretions, we found that excess zinc treatment induced secretion of NA in A. halleri roots compared with the nonhyperaccumulator Arabidopsis thaliana. Metal speciation analysis further revealed that the secreted NA forms a stable complex with Zn(II). Supplying NA to a nonhyperaccumulator species markedly increased plant zinc tolerance by decreasing zinc uptake. Therefore, NA secretion from A. halleri roots facilitates zinc hypertolerance through forming a Zn(II)-NA complex outside the roots to achieve a coordinated zinc uptake rate into roots. Secretion of NA was also found to be responsible for the maintenance of iron homeostasis under excess zinc. Together our results reveal root-secretion mechanisms associated with hypertolerance and hyperaccumulation. © 2014 American Society of Plant Biologists. All Rights Reserved.

  20. Fabrications of zinc-releasing biocement combining zinc calcium phosphate to calcium phosphate cement.

    Science.gov (United States)

    Horiuchi, Shinya; Hiasa, Masahiro; Yasue, Akihiro; Sekine, Kazumitsu; Hamada, Kenichi; Asaoka, Kenzo; Tanaka, Eiji

    2014-01-01

    Recently, zinc-releasing bioceramics have been the focus of much attention owing to their bone-forming ability. Thus, some types of zinc-containing calcium phosphate (e.g., zinc-doped tricalcium phosphate and zinc-substituted hydroxyapatite) are examined and their osteoblastic cell responses determined. In this investigation, we studied the effects of zinc calcium phosphate (ZCP) derived from zinc phosphate incorporated into calcium phosphate cement (CPC) in terms of its setting reaction and MC3T3-E1 osteoblast-like cell responses. Compositional analysis by powder X-ray diffraction analysis revealed that HAP crystals were precipitated in the CPC containing 10 or 30wt% ZCP after successfully hardening. However, the crystal growth observed by scanning electron microscopy was delayed in the presence of additional ZCP. These findings indicate that the additional zinc inhibits crystal growth and the conversion of CPC to the HAP crystals. The proliferation of the cells and alkaline phosphatase (ALP) activity were enhanced when 10wt% ZCP was added to CPC. Taken together, ZCP added CPC at an appropriate fraction has a potent promotional effect on bone substitute biomaterials.