Comparative study of objective and subjective parameters of accommodation in children with myopia

AIM: The study aims to compare the results of objective parameters such as autorefractometers of the open field Grand Seiko and closed field TONOREF III. and the subjective parameters such as the positive of relative accommodation (PRA) and the amplitude of accommodation (AA). MATERIAL AND METHODS: 30 children (60 eyes) with low and moderate myopia (on average -2.96 0.17 D) aged from 8 to 12 years (on average 10.04 0.24 years) were examined. Subjective (PRA, AA) and objective parameters of binocular adaptation (BAO) and monocular adaptation (MAO) response on the Grand Seiko Binocular Open Field Autorefkeratometer WR - 5500K (Japan) and the AA on the automatic refractokeratotonometer pakhimetre TONOREF III (Nidek, Japan) were determined. RESULTS: The average of BAO and MAO at 33 cm was -1.93 0.04 D and 1.86 0.05 D, respectively. The average PRA was 1.5 0.16 D. The objectively measured average AA was 5.25 0.4 D. The average minimum AA value was -2.86 0.16 D, and the average maximum value was 8.11 0.46 D. The subjective AA on the Iksar device was on average 4.17 0.43 D; Amin, on average -3.77 0.26 D; Amax, on average was -7.94 0.59 D. CONCLUSION: The objective and subjective measurements of AA produced comparable results. BAO and MAO reflected other characteristics of accommodation, different from its amplitude, and characterized the adequacy of the accommodation response to a specific accommodation task. The advantage of objective accommodation is that it is independent of the patients responses and intellectual level.

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Filtering Activity and Nutrient Release by the Keratose Sponge Sarcotragus spinosulus Schmidt, 1862 (Porifera, Demospongiae) at the Laboratory Scale

Journal of Marine Science and Engineering ◽

10.3390/jmse9020178 ◽

2021 ◽

Vol 9 (2) ◽

pp. 178

Author(s):

Roberta Trani ◽

Giuseppe Corriero ◽

Maria Concetta de Pinto ◽

Maria Mercurio ◽

Carlo Pazzani ◽

...

Keyword(s):

Benthic Communities ◽

Nutrient Release ◽

Nutrient Load ◽

Promising Candidate ◽

Filter Feeder ◽

Retention Efficiency ◽

Maximum Value ◽

Average Maximum ◽

Microbial Bioremediation ◽

Maximum Retention

Sponges are an important constituent of filter-feeder benthic communities, characterized by high ecological plasticity and abundance. Free bacteria constitute an important quota of their diet, making them excellent candidates in aquaculture microbial bioremediation, where bacteria can be a serious problem. Although there are studies on this topic, certain promising species are still under investigation. Here we report applied microbiological research on the filtering activity of Sarcotragus spinosulus on two different concentrations of the pathogenic bacterium Vibrio parahaemolyticus in a laboratory experiment. To evaluate the effects of the filtration on the surrounding nutrient load, the release of ammonium, nitrate, and phosphate was also measured. The results obtained showed the efficient filtration capability of S. spinosulus as able to reduce the Vibrio load with a maximum retention efficiency of 99.72% and 99.35% at higher and lower Vibrio concentrations, respectively, and remarkable values of clearance rates (average maximum value 45.0 ± 4.1 mL h−1 g DW−1) at the highest Vibrio concentration tested. The nutrient release measured showed low values for each considered nutrient category at less than 1 mg L−1 for ammonium and phosphate and less than 5 mg L−1 for nitrate. The filtering activity and nutrient release by S. spinosulus suggest that this species represents a promising candidate in microbial bioremediation, showing an efficient capability in removing V. parahaemolyticus from seawater with a contribution to the nutrient load.

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Evaluation of Cherry Tomato Genotypes for Qualitative Traits under Open Field and Protected Condition

International Research Journal of Pure and Applied Chemistry ◽

10.9734/irjpac/2020/v21i930194 ◽

2020 ◽

pp. 9-16

Author(s):

. Chandni ◽

Deepti Singh ◽

Shirin Akhtar ◽

Shiv Shankar Mahesh

Keyword(s):

Ascorbic Acid ◽

Open Field ◽

Ascorbic Acid Content ◽

Quality Parameters ◽

Soluble Solids ◽

Vegetable Crops ◽

Cherry Tomato ◽

Total Soluble Solids ◽

Maximum Value ◽

Β Carotene

Vegetable, due to higher neutraceutical component, are termed as protective food against various major and minor diseases. Scientific agro-techniques under optimum growing condition like temperature, relative humidity and light intensity, positively influence the qualitative and quantitative attributes of most of the vegetable crops including cherry tomato. It is one of potential vegetable crop, which is extensively utilized for table purpose and for preparing recipies in five star restaurants. Cherry tomato fetches higher prices in market due to good taste and higher nutrients, thus making qualitative attributes as an important factor to give higher returns to the farmers. Thus, this experiment was conducted to estimate the qualitative attributes in eighteen genotypes of cherry tomato grown under both open field and polyhouse conditions. The result of the study revealed that under open field condition, BRCT-30 was the best genotype with maximum value for lycopene content (6.62 mg 100-1 g FW) and β-carotene (2.30 mg 100-1 g FW), second maximum value for total soluble solids (7.85°Brix), third maximum value for reducing sugar and fourth highest position for ascorbic acid content (43.65 mg/100 g FW). Under polyhouse condition, the best genotype for quality parameters was BRCT-36 with maximum total soluble solids (10.81°Brix), lycopene (7.48 mg 100-1 g FW) and β-carotene (2.49 mg 100-1g FW) along with average range of values for ascorbic acid (72.36 mg 100-1 g FW) and titrable acidity (0.55 mg 100-1 g FW).

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Dynamical critical scaling of electric field fluctuations in the greater cusp and magnetotail implied by HF radar observations of F-region Doppler velocity

Annales Geophysicae ◽

10.5194/angeo-24-689-2006 ◽

2006 ◽

Vol 24 (2) ◽

pp. 689-705 ◽

Cited By ~ 17

Author(s):

M. L. Parkinson

Keyword(s):

Solar Wind ◽

Open Field ◽

Electric Fields ◽

Spectral Width ◽

Hf Radar ◽

Doppler Velocity ◽

Closed Field ◽

Scaling Exponent ◽

Central Plasma ◽

Field Lines

Abstract. Akasofu's solar wind ε parameter describes the coupling of solar wind energy to the magnetosphere and ionosphere. Analysis of fluctuations in ε using model independent scaling techniques including the peaks of probability density functions (PDFs) and generalised structure function (GSF) analysis show the fluctuations were self-affine (mono-fractal, single exponent scaling) over 9 octaves of time scale from ~46 s to ~9.1 h. However, the peak scaling exponent α0 was a function of the fluctuation bin size, so caution is required when comparing the exponents for different data sets sampled in different ways. The same generic scaling techniques revealed the organisation and functional form of concurrent fluctuations in azimuthal magnetospheric electric fields implied by SuperDARN HF radar measurements of line-of-sight Doppler velocity, vLOS, made in the high-latitude austral ionosphere. The PDFs of vLOS fluctuation were calculated for time scales between 1 min and 256 min, and were sorted into noon sector results obtained with the Halley radar, and midnight sector results obtained with the TIGER radar. The PDFs were further sorted according to the orientation of the interplanetary magnetic field, as well as ionospheric regions of high and low Doppler spectral width. High spectral widths tend to occur at higher latitude, mostly on open field lines but also on closed field lines just equatorward of the open-closed boundary, whereas low spectral widths are concentrated on closed field lines deeper inside the magnetosphere. The vLOS fluctuations were most self-affine (i.e. like the solar wind ε parameter) on the high spectral width field lines in the noon sector ionosphere (i.e. the greater cusp), but suggested multi-fractal behaviour on closed field lines in the midnight sector (i.e. the central plasma sheet). Long tails in the PDFs imply that "microbursts" in ionospheric convection occur far more frequently, especially on open field lines, than can be captured using the effective Nyquist frequency and volume resolution of SuperDARN radars.

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Differential rotation in neutron stars with open and closed magnetic topologies

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa915 ◽

2020 ◽

Vol 494 (3) ◽

pp. 3095-3109

Author(s):

F Anzuini ◽

A Melatos

Keyword(s):

Magnetic Field ◽

Field Line ◽

Open Field ◽

Flux Tube ◽

Differential Rotation ◽

Time Scale ◽

Outer Sphere ◽

Closed Field ◽

Magnetic Tension ◽

Field Lines

ABSTRACT Analytic arguments have been advanced that the degree of differential rotation in a neutron star depends on whether the topology of the internal magnetic field is open or closed. To test this assertion, the ideal-magnetohydrodynamics solver pluto is employed to investigate numerically the flow of an incompressible, viscous fluid threaded by a magnetic field with open and closed topologies in a conducting, differentially rotating, spherical shell. Rigid body corotation with the outer sphere is enforced on the Alfvén time-scale, along magnetic field lines that connect the northern and southern hemispheres of the outer sphere. Along other field lines, however, the behaviour is more complicated. For example, an initial point dipole field evolves to produce an approximately closed equatorial flux tube containing at least one predominantly toroidal and approximately closed field line surrounded by a bundle of predominantly toroidal but open field lines. Inside the equatorial flux tube, the field-line-averaged magnetic tension approaches zero, and the fluid rotates differentially, adjusting its angular velocity on the viscous time-scale to match the boundary conditions on the flux tube’s toroidal surface. Outside the equatorial flux tube, the differential rotation increases, as the magnetic tension averaged along open field lines decreases.

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A Comparative Study of Mechanical Properties in Ion-Irradiated A12O3 and MgO·nAl203

MRS Proceedings ◽

10.1557/proc-540-317 ◽

1998 ◽

Vol 540 ◽

Cited By ~ 1

Author(s):

K. Yasuda ◽

C. Kinoshita ◽

K. Izumi

Keyword(s):

Mechanical Properties ◽

Comparative Study ◽

Lattice Constant ◽

Point Defects ◽

Recombination Rate ◽

Radiation Hardening ◽

Maximum Value ◽

Plastic Hardening ◽

Load Displacement ◽

The Difference

AbstractWe have investigated radiation hardening in alumina (A1203), stoichiometric and nonstoichiometric spinel (MgO·nA1203: n= 1, 2.4) crystals at 300 K irradiated with 100 keV He+ ions by using a ultra-microhardness technique. Al203 shows a remarkable radiation hardening (35% increase in hardness) at a fluence of 5×1019 He+/m2 and saturates at 60 % of the maximum value at fluences higher than 8×1019 He+/m2. In spinel crystals, hardness increases monotonically with fluence, reaching to a saturation at a fluence of 1×1020He+/m2. Analyses of load- displacement curves indicate that both plastic and elastic hardening are responsible for the radiation hardening in A1203, and that plastic hardening is the main cause in MgO'nAl2O3. Microstructure observations and lattice constant measurements showed that point defects are mainly responsible for the radiation hardening in both A1203 and MgO·nAl2O3. The difference in the radiation hardening response is discussed in terms of the difference in recombination rate of point defects among the MgO-A1203 system ceramics.

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Analisis Kinerja Routing Protokol AODV pada Jaringan VANET (Studi Kasus : Kecamatan Cakranegara)

Jurnal Teknologi Informasi, Komputer, dan Aplikasinya (JTIKA ) ◽

10.29303/jtika.v1i2.19 ◽

2019 ◽

Vol 1 (2) ◽

Author(s):

Muhamad Zaelani Syahrir Ramadhan ◽

I Wayan Agus Arimbawa ◽

Moh Ali Albar

Keyword(s):

Ad Hoc ◽

Packet Delivery Ratio ◽

Delivery Ratio ◽

Routing Overhead ◽

Average Speed ◽

Packet Delivery ◽

Minimum Value ◽

End To End Delay ◽

Maximum Value ◽

Average Maximum

Vehicular Ad-hoc Network is the concept of a subset of Mobile Ad-Hoc Networks (MANET) where vehicles act as nodes on the network. Protocol routing is very influential on the performance of the network to deal with challenges related to the rapidly changing network topology. This study analyze the routing performance of the AODV protocol on vanet networks in the district of Cakranegara by analyzing performance results using end to end delay parameters, packet delivery ratio (PDR), throughput, and routing overhead. The average Maximum value at end to end delay is 940.577 ms while the minimum value is 50,065 ms, and the average speed value decreases delay at speed 50 to 30 km / h by 78,314 ms and from 30 to 10 km / hour decreased by 102,827 ms. The maximum average value in the packet delivery ratio is 84.75% while the minimum value is 55.33%, and the average speed value decreases the ratio at the speed of 50 to 30 km / hour by 7.26% and from 30 to 10 km / h has increased by 10.39%. The average maximum value at throughput is 69,553 Kbps while the minimum value is 10.06 Kbps, and the average speed value decreases throughput at speeds of 50 to 30 km / h by 1,065 Kbps and from 30 to 10 km / h decreases amounting to 0.658 Kbps. The average Maximum value on routing overhead is 37,311 bytes while the minimum value is 7,439 bytes, and the average speed value increases at a speed of 50 to 30 km / hour by 1,321 Bytes and from 30 to 10 km / hour decreases by 5,453 Bytes. Key words: AODV, VANET, Routing Protocols, SUMO, NS2.

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A comparative study between the addition of nano and micro-particles of Co3O4 on the electrical and microstructural properties of a ceramic system based on SnO2

Revista Mexicana de Física ◽

10.31349/revmexfis.66.47 ◽

2019 ◽

Vol 66 (1) ◽

pp. 47

Author(s):

M. I Miranda López ◽

M. B. Hernández Hernández ◽

B. S. Vera Barrios ◽

A. Toxqui Teran ◽

J. A. Aguilar Martinez

Keyword(s):

Comparative Study ◽

Sintering Temperature ◽

Electrical Breakdown ◽

Rietveld Analysis ◽

Nano Particles ◽

Particle Sizes ◽

Linear Coefficient ◽

Ohmic Behavior ◽

Micro Particles ◽

Maximum Value

A comparative study between the addition of Co3O4 micro-particles and nano-particles as densifying dopant of a SnO2 based varistor system was conducted. The ceramic composition was (99.9-X) %SnO2–X %Co3O4–0.05 %Cr2O3–0.05 %Nb2O5 where X = 0, 0.5, 1.0, 2.0 and 4.0 mol%. Two particle sizes of Co3O4 were used (~5 µm and ~50 nm). The addition of 0.5 mol% of Co3O4 nano-particles promoted an increase of grain size of sintered samples up to 7.9 µm, that is, the maximum value among all variations. Characterization techniques such as TGA, DTA, XRD, and Rietveld analysis revealed a decrease of 16 ºC in the formation temperature of Co2SnO4 as well as an increase of 2.6 wt% in the amount of said phase with the use of 4.0 mol% of Co3O4 nano-particles in comparison with micro-particles. Statistical analysis indicated that the addition of nano-particles of Co3O4 yield better repeatability on densification of ceramic samples. Residual porosity also was decreased. Electrical breakdown and non-linear coefficient values correspond to a non-ohmic behavior with potential application on manufacture of high voltage varistors. The findings of this work can be used as a reference for conducting a later study to improve the electrical properties or even to lower the sintering temperature.

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Nightside studies of coherent HF Radar spectral width behaviour

Annales Geophysicae ◽

10.5194/angeo-20-1399-2002 ◽

2002 ◽

Vol 20 (9) ◽

pp. 1399-1413 ◽

Cited By ~ 4

Author(s):

E. E. Woodfield ◽

J. A. Davies ◽

M. Lester ◽

T. K. Yeoman ◽

P. Eglitis ◽

...

Keyword(s):

Case Studies ◽

Open Field ◽

Local Time ◽

Frictional Heating ◽

Spectral Width ◽

Hf Radar ◽

Closed Field ◽

Multiple Peak ◽

Field Lines

Abstract. A previous case study found a relationship between high spectral width measured by the CUTLASS Finland HF radar and elevated electron temperatures observed by the EISCAT and ESR incoherent scatter radars in the post-midnight sector of magnetic local time. This paper expands that work by briefly re-examining that interval and looking in depth at two further case studies. In all three cases a region of high HF spectral width (>200 ms-1) exists poleward of a region of low HF spectral width (<200 ms-1). Each case, however, occurs under quite different geomagnetic conditions. The original case study occurred during an interval with no observed electrojet activity, the second study during a transition from quiet to active conditions with a clear band of ion frictional heating indicating the location of the flow reversal boundary, and the third during an isolated sub-storm. These case studies indicate that the relationship between elevated electron temperature and high HF radar spectral width appears on closed field lines after 03:00 magnetic local time (MLT) on the nightside. It is not clear whether the same relationship would hold on open field lines, since our analysis of this relationship is restricted in latitude. We find two important properties of high spectral width data on the nightside. Firstly the high spectral width values occur on both open and closed field lines, and secondly that the power spectra which exhibit high widths are both single-peak and multiple-peak. In general the regions of high spectral width (>200 ms-1) have more multiple-peak spectra than the regions of low spectral widths whilst still maintaining a majority of single-peak spectra. We also find that the region of ion frictional heating is collocated with many multiple-peak HF spectra. Several mechanisms for the generation of high spectral width have been proposed which would produce multiple-peak spectra, these are discussed in relation to the data presented here. Since the regions of high spectral width are observed both on closed and open field lines the use of the boundary between low and high spectral width as an ionospheric proxy for the open/closed field line boundary is not a simple matter, if indeed it is possible at all.Key words. Ionosphere (auroral ionosphere; ionospheric irregularities)

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