scholarly journals Highly sensitive and reusable Pt-black microfluidic electrodes for long-term electrochemical sensing

2010 ◽  
Vol 26 (2) ◽  
pp. 682-688 ◽  
Author(s):  
Liangliang Qiang ◽  
Santhisagar Vaddiraju ◽  
James F. Rusling ◽  
Fotios Papadimitrakopoulos
Author(s):  
T. M. Seed ◽  
M. H. Sanderson ◽  
D. L. Gutzeit ◽  
T. E. Fritz ◽  
D. V. Tolle ◽  
...  

The developing mammalian fetus is thought to be highly sensitive to ionizing radiation. However, dose, dose-rate relationships are not well established, especially the long term effects of protracted, low-dose exposure. A previous report (1) has indicated that bred beagle bitches exposed to daily doses of 5 to 35 R 60Co gamma rays throughout gestation can produce viable, seemingly normal offspring. Puppies irradiated in utero are distinguishable from controls only by their smaller size, dental abnormalities, and, in adulthood, by their inability to bear young.We report here our preliminary microscopic evaluation of ovarian pathology in young pups continuously irradiated throughout gestation at daily (22 h/day) dose rates of either 0.4, 1.0, 2.5, or 5.0 R/day of gamma rays from an attenuated 60Co source. Pups from non-irradiated bitches served as controls. Experimental animals were evaluated clinically and hematologically (control + 5.0 R/day pups) at regular intervals.


2018 ◽  
Vol 10 (4) ◽  
pp. 109-134 ◽  
Author(s):  
Moritz A. Drupp ◽  
Mark C. Freeman ◽  
Ben Groom ◽  
Frikk Nesje

The economic values of investing in long-term public projects are highly sensitive to the social discount rate (SDR). We surveyed over 200 experts to disentangle disagreement on the risk-free SDR into its component parts, including pure time preference, the wealth effect, and return to capital. We show that the majority of experts do not follow the simple Ramsey Rule, a widely used theoretical discounting framework, when recommending SDRs. Despite disagreement on discounting procedures and point values, we obtain a surprising degree of consensus among experts, with more than three-quarters finding the median risk-free SDR of 2 percent acceptable. (JEL C83, D61, D82, H43, Q58)


2014 ◽  
Vol 94 (1) ◽  
pp. 33-39 ◽  
Author(s):  
D. J. Thompson ◽  
W. D. Willms

Thompson, D. J. and Willms, W. D. 2014. Effects of long-term protection from grazing on phenotypic expression in geographically separated mountain rough fescue populations. Can. J. Plant Sci. 94: 33–39. Whether or not long-term grazing or protection from grazing alters the genetic makeup of grass populations has been debated. Mountain rough fescue [(Festuca campestris (Rydb.)], which is highly sensitive to summer grazing, and becomes dominant in plant communities with long-term protection, was chosen to address this question. Plants from three geographic sites (Stavely in AB, Milroy in the Kootenay trench, BC and Goose Lake on the BC interior plateau) with divergent grazing histories were vegetatively propagated from tillers. Daughter plants were planted into two field nurseries (at Kamloops, BC, and Stavely, AB) and morphological measurements were taken in two field seasons post-establishment. Plants from all three populations were taller, flowered earlier, and were more productive at the Kamloops nursery site. Of the three geographic sources, plants from the Goose Lake site were most distinct with narrower leaves, later flowering, and greater yield. Plants with a long history of grazing had slightly shorter fertile tillers and leaves than plants with a history of long-term protection.


2020 ◽  
Vol 9 (3) ◽  
pp. 152-157
Author(s):  
Rinat R. Fatkullin ◽  
Aikumis K. Saken

Abnormal environmental factors contribute to advanced behavioral strategies in higher regulatory centers as well as to the assessment of possible morphofunctional and energy transformations in the body. Animals, especially birds, which are characterized by curiosity, are highly sensitive to the presence of environmental pollution, since they interact with elements of the environment and surroundings. Contamination of broiler products can also be caused by contaminated soil and dust, unknown sources of persistent heavy metals and organic pollutants that are unknown to the public, such as car wreckage, household waste, and so on. In general, adverse factors that regularly affect small details do not require significant changes in the body at the initial stage, mainly affect non-specific mechanisms that lead to long-term activation. The paper contains significant work based on the analysis of microbiogenic links in the trophic chain, but the formation of processes associated with metabolic disorders from the development of trace elements to clinical manifestations is still insufficiently studied, so it is difficult to diagnose and treat previously unknown animal diseases in veterinary practice.


2020 ◽  
Vol 44 (37) ◽  
pp. 15975-15982
Author(s):  
Xueliang Niu ◽  
Weili Zhang ◽  
Yan Huang ◽  
Likai Wang ◽  
Zhongfang Li ◽  
...  

A novel electrochemical method for highly sensitive determination of baicalein was developed with Au@Ag/3DNGA as signal amplifier.


Sensors ◽  
2019 ◽  
Vol 19 (22) ◽  
pp. 4906 ◽  
Author(s):  
María Elena Martínez-Hernández ◽  
Javier Goicoechea ◽  
Francisco J. Arregui

Mercury is an important contaminant since it is accumulated in the body of living beings, and very small concentrations are very dangerous in the long term. This paper reports the fabrication of a highly sensitive fiber optic sensor using the layer-by-layer nano-assembly technique with gold nanoparticles (AuNPs). The gold nanoparticles were obtained via a water-based synthesis route that use poly acrylic acid (PAA) as stabilizing agent, in the presence of a borane dimethylamine complex (DMAB) as reducing agent, giving PAA-capped AuNPs. The sensing mechanism is based on the alteration of the Localized Surface Plasmon Resonances (LSPR) generated by AuNPs thanks to the strong chemical affinity of metallic mercury towards gold, which lead to amalgam alloys.


NANO ◽  
2019 ◽  
Vol 14 (11) ◽  
pp. 1950138 ◽  
Author(s):  
Sai Zhang ◽  
Shijun Yue ◽  
Jiajia Li ◽  
Jianbin Zheng ◽  
Guojie Gao

Au nanoparticles anchored on core–shell [Formula: see text]-Fe2O3@SnO2 nanospindles were successfully constructed through hydrothermal synthesis process and used for fabricating a novel nonenzymatic dopamine (DA) sensor. The structure and morphology of the Au/[Formula: see text]-Fe2O3@SnO2 trilaminar nanohybrid film were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The electrochemical properties of the sensor were investigated by cyclic voltammetry and amperometry. The experimental results suggest that the composites have excellent catalytic property toward DA with a wide linear range from 0.5[Formula: see text][Formula: see text]M to 0.47[Formula: see text]mM, a low detection limit of 0.17[Formula: see text][Formula: see text]M (S/[Formula: see text]) and high sensitivity of 397.1[Formula: see text][Formula: see text]A[Formula: see text]mM[Formula: see text][Formula: see text]cm[Formula: see text]. In addition, the sensor exhibits long-term stability, good reproducibility and anti-interference.


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