Batch grinding kinetics with assumptions is applied to continuous tube milling to describe the grinding performance, relating the degree of size reduction to the milling conditions including the ...scale-up variables. As to the scale-up effect on the degree of size reduction, the trend predicted is confirmed with that observed in industrial cement mills in reasonable agreement. The equation of the grinding performance alone, however, does not evaluate the mill diameter and the length individually nor guarantee the powder filling to be a desired level. Then, it is proposed to use one more equation representing the material hold-up (or the powder filling) in relation to the milling conditions. That is, the solution of the two simultaneous equations enables the two variables (the mill diameter and the length) to be evaluated, satisfying the powder filling to be a desired value.
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•Batch grinding kinetics with assumptions is applied to continuous milling.•The grinding performance or the size reduction is related to milling conditions.•The scale-up effect on size reduction is confirmed with cement mill data.•The material hold-up equation assures the powder filling level as desired.•Simultaneous use of grinding performance and hold-up equations is demonstrated.
In our studies of life‐supporting α‐1,3‐galactocyltransferase knockout (GalT‐KO) pig‐to‐baboon kidneys, we found that some recipients developed increased serum creatinine with growth of the grafts, ...without histological or immunological evidence of rejection. We hypothesized that the rapid growth of orthotopic pig grafts in smaller baboon recipients may have led to deterioration of organ function. To test this hypothesis for both kidneys and lungs, we assessed whether the growth of outbred (Yorkshire) organ transplants in miniature swine was regulated by intrinsic (graft) or extrinsic (host environment) factors. Yorkshire kidneys exhibited persistent growth in miniature swine, reaching 3.7 times their initial volume over 3 mo versus 1.2 times for miniature swine kidneys over the same time period. Similar rapid early growth of lung allografts was observed and, in this case, led to organ dysfunction. For xenograft kidneys, a review of our results suggests that there is a threshold for kidney graft volume of 25 cm3/kg of recipient body weight at which cortical ischemia is induced in transplanted GalT‐KO kidneys in baboons. These results suggest that intrinsic factors are responsible, at least in part, for growth of donor organs and that this property should be taken into consideration for growth‐curve–mismatched transplants, especially for life‐supporting organs transplanted into a limited recipient space.
Factors intrinsic to transplanted organs play a role in subsequent growth of those organs, suggesting that this property should be considered for growth‐curve mismatched transplants, especially when transplanting life‐supporting organs into limited recipient space.
We describe the realization of a homemade and portable setup to perform experiments of pulsed magnetic resonance of nitrogen-vacancy (NV) centers in diamonds. The system is fully implemented by using ...an Arduino Uno board equipped with an AVR microcontroller that is used as a transistor-transistor logic pulse sequencer to drive precise laser and microwave pulses with a resolution of 62.5 ns. The equipment is assembled with low-cost modules on a printed circuit board and placed in a compact box with a volume of 20 × 40 × 10 cm3. The detection system is based on a switched integrator and a photodiode in the vicinity of a diamond substrate and read by oversampling the analog-to-digital converter of Arduino Uno. We characterize a CVD diamond sample by performing the pulsed optically detected magnetic resonance and we show the possibility to perform a coherent manipulation of the electron spin of NV centers by driving Rabi oscillations up to 6 MHz with microwave powers within 1 W. We demonstrate different pulse sequences to study electron spin relaxation and dephasing. Finally, we propose additional modules and an antenna to perform the multifrequency manipulation of the electron spin by microwave and radio-frequency pulses. Compared to the previous studies, our system results in a low-cost setup with significantly reduced complexity, which finds application as a learning module for science education and enables a wider audience to access the magnetic resonance in diamond.
The present paper deals with a theoretical analysis of the dispersion properties, the dispersion coefficient and the Peclet number, of particulate material in a continuous ball mill. In the analysis, ...a dispersion zone where the brief dispersion of particles occurs, is postulated in the lower portion of an operated mill called the grinding zone. Consequently, the dispersion coefficient is derived to be a function of the size of the dispersion zone and the mobility of balls in the grinding zone and the Peclet number is a function of the dispersion coefficient, the axial mean velocity of material flowing and the mill length. Results derived from the theory are within reasonable agreement with reported data for dry and wet grinding operations, although minor variations are observed between theory and experiment. Additionally, the mill diameter and length are predicted to affect greatly the Peclet number, implying the importance of designing mill sizes for required product size distributions as the residence time distribution is dominated by the Peclet number. Further, a proportional relationship to predict the Peclet number is derived, which appears to be valid as confirmed with data regardless of the mill sizes tested.
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► The dispersion properties in a continuous ball mill are analyzed theoretically. ► The Peclet number determines the residence time distribution. ► Trends derived from the theory are within agreement with data reported. ► Mill length and diameter are predicted to affect greatly the Peclet number. ► A proportional relation for the Peclet number is valid regardless of mill sizes.
On March 28, the Japanese government decided on the “Basic Policies for Novel Coronavirus Disease Control” and called on the public to thoroughly implement social distancing measures (i.e., ...behavioral restrictions to limit the frequency and intensity of human contact), especially telework.
We used population-level questionnaire data from a social networking service (SNS), with 275,560 respondents from March 5 to April 6, to evaluate the relationship between telework implementation and the presence of a fever (body temperature higher than 37.5 °C) within 1 month as a surrogate indicator of COVID-19 infection, by occupation type and age-group.
Among company employees, statistical significance was identified in the 15- to 29-year and 30- to 59-year age-groups, showing higher fever rates in the non-teleworker group (for the 15- to 29-year age-group, non-teleworkers: 7.64%; teleworkers: 6.45%; P = 0.02; for the 30- to 59-year age-group, non-teleworkers: 3.46%; teleworkers: 3.14%; P = 0.02).
Telework remains a controversial topic in Japan as the government called for emergency measures. Although caution is warranted in interpreting our findings because our data are limited to the voluntary SNS users, they will be essential to push forward with more measures to promote social distancing measures in the midst of Japan's current tense political climate.
•Slow progress in the introduction of telework as a coronavirus disease 2019 (COVID-19) measure in Japan.•Analysis using COVID-19 monitoring responses from over 270,000 social networking service users in Japan.•Statistical relationship between teleworking and fever among company employees.•The urgent need for social support in the implementation of telework in Japan.
In Japan, several studies have reported no excess all-cause deaths (the difference between the observed and expected number of deaths) during the coronavirus disease 2019 (COVID-19) pandemic in 2020. ...This study aimed to estimate the weekly excess deaths in Japan's 47 prefectures for 2021 until June 27.
Vital statistical data on deaths were obtained from the Ministry of Health, Labour and Welfare of Japan. For this analysis, we used data from January 2012 to June 2021.
A quasi-Poisson regression was used to estimate the expected weekly number of deaths. Excess deaths were expressed as the range of differences between the observed and expected number of all-cause deaths and the 95% upper bound of the one-sided prediction interval.
Since January 2021, excess deaths were observed for the first time in the week corresponding to April 12–18 and have continued through mid-June, with the highest excess percentage occurring in the week corresponding to May 31–June 6 (excess deaths: 1431–2587; excess percentage: 5.95–10.77%). Similarly, excess deaths were observed in consecutive weeks from April to June 2021 in 18 of 47 prefectures.
For the first time since February 2020, when the first COVID-19 death was reported in Japan, excess deaths possibly related to COVID-19 were observed in April 2021 in Japan, during the fourth wave. This may reflect the deaths of non-infected people owing to the disruption that the pandemic has caused.
The physical and chemical characteristics of peat were assessed through measurement of pH, percentage of organic matter, cationic exchange capacity (CEC), elemental analysis, infrared spectroscopy ...and quantitative analysis of metals by ICP OES. Despite the material showed to be very acid in view of the percentage of organic matter, its CEC was significant, showing potential for retention of metal ions. This characteristic was exploited by coupling a peat mini-column to a flow system based on the multicommutation approach for the in-line copper concentration prior to flame atomic absorption spectrometric determination. Cu(II) ions were adsorbed at pH 4.5 and eluted with 0.50
mol
L
−1 HNO
3. The influence of chemical and hydrodynamic parameters, such as sample pH, buffer concentration, eluent type and concentration, sample flow-rate and preconcentration time were investigated. Under the optimized conditions, a linear response was observed between 16 and 100
μg
L
−1, with a detection limit estimated as 3
μg
L
−1 at the 99.7% confidence level and an enrichment factor of 16. The relative standard deviation was estimated as 3.3% (
n
=
20). The mini-column was used for at least 100 sampling cycles without significant variation in the analytical response. Recoveries from copper spiked to lake water or groundwater as well as concentrates used in hemodialysis were in the 97.3–111% range. The results obtained for copper determination in these samples agreed with those achieved by graphite furnace atomic absorption spectrometry (GFAAS) at the 95% confidence level.
Gene Expression within Cell-Sized Lipid Vesicles Nomura, Shin-ichiro M; Tsumoto, Kanta; Hamada, Tsutomu ...
Chembiochem : a European journal of chemical biology,
November 7, 2003, Letnik:
4, Številka:
11
Journal Article
Recenzirano
Functional protein synthesis was observed in cell-sized lipid vesicles following encapsulation of a gene-expression system. Expression of rsGFP (red-shifted green fluorescent protein) within ...individual vesicles was observed by fluorescence microscopy. Interestingly, at the early stage of the reaction, the expression efficiency inside the vesicle was remarkably higher than that in the solution outside. The synthesized rsGFP in individual vesicles is safe from attack by proteinase K added to the external aqueous solution. Studies on cell-sized vesicles expressing protein should contribute to a fundamental understanding of certain aspects of living systems and will be useful for practical applications, such as the construction of microreactors.
The metabotropic glutamate receptors (mGluRs) have distinct distribution patterns in the CNS but subtypes within group I or group III mGluRs share similar ultrastructural localization relative to ...neurotransmitter release sites: group I mGluRs are concentrated in an annulus surrounding the edge of the postsynaptic density, whereas group III mGluRs are concentrated in the presynaptic active zone. One of the group II subtypes, mGluR2, is expressed in both pre- and postsynaptic elements, having no close association with synapses. In order to determine if such a distribution is common to another group II subtype, mGluR3, an antibody was raised against a carboxy-terminus of mGluR3 and used for light and electron microscopic immunohistochemistry in the mouse CNS. The antibody reacted strongly with mGluR3, but it also reacted, though only weakly, with mGluR2. Therefore, to examine mGluR3-selective distribution, we used mGluR2-deficient mice as well as wild-type mice.
Strong immunoreactivity for mGluR3 was found in the cerebral cortex, striatum, dentate gyrus of the hippocampus, olfactory tubercle, lateral septal nucleus, lateral and basolateral amygdaloid nuclei, and nucleus of the lateral olfactory tract. Pre-embedding immunoperoxidase and immunogold methods revealed mGluR3 labeling in both presynaptic and postsynaptic elements, and also in glial profiles. Double labeling revealed that the vast majority of mGluR3 in presynaptic elements is not closely associated with glutamate and GABA release sites in the striatum and thalamus, respectively. However, in the spines of the dentate granule cells, the highest receptor density was found in perisynaptic sites (20% of immunogold particles within 60 nm from the edge of postsynaptic membrane specialization) followed by a decreasing receptor density away from the synapses (to ∼5% of particles per 60 nm). Furthermore, 19% of immunogold particles were located in asymmetrical postsynaptic specialization, indicating an association of mGluR3 to glutamatergic synapses.
The present results indicate that the localization of mGluR3 is rather similar to that of group I mGluRs in the postsynaptic elements, suggesting a unique functional role of mGluR3 in glutamatergic neurotransmission in the CNS.
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