The influence factors of mean particle size and positive quality control of bacterial filtration efficiency system

Summary Background The Coronavirus Disease 2019 (COVID-19) has swept the whole world with high mortality. Since aerosol transmission is the main route of transmission, wearing a mask serves as a crucial preventive measure. An important parameter to evaluate the performance of a mask is the bacteria filtration efficiency (BFE). Aerosol mean particle size (MPS) and positive quality control value are two key indexes of BFE system. Aim To study the major influence factors of the mean particle size of bacterial aerosols and positive quality control value of BFE system. Method and Results In this study, we investigated the influence of Anderson sampler, spray flow, medium thickness, and peristaltic pump flow on the MPS of bacterial aerosols and positive quality control value of BFE system, respectively. The results show that the machining accuracy of Anderson sampler has great influence on aerosol MPS and positive quality control value. With the increase of aerosol spray flow rate, the positive quality control value will increase gradually, but the effect on aerosol MPS is not a simple linear relationship. As the agar medium thickness increased, the positive quality control value and aerosol MPS increased gradually. With the increase of peristaltic pump flow, the positive quality control value increased gradually, while the aerosol MPS was basically in a downward trend. When the peristatic pump flow rate was 0.1mL/min, the spray flow rate was 7.2L/min, the agar plate thickness was 27mL, and the Anderson sampler of Beijing Mingjie was used for the experiment, the aerosol MPS and positive quality control value were both within the acceptable range and were the optimal parameters. Conclusions This study provides guidance for the manufacturers of the BFE system and improves the protective performance of masks, which is important for the human health, especially during the occurrence of viral pandemics such as "COVID-19".

Generosity in Buddhist thought and generous education for today's Vietnamese students

With the theory of reincarnation and karma, Buddhism thinks that everything has cause and effect, the sowing cause will reap that fruit. Therefore, in order to be reborn in good lives after death, people need to sow good karma. From a moral perspective, we all know that generosity is a positive quality, people should practice to live in harmony in society. When we do a good thing, there will be a wealth of benefits that it can bring. That may be the subject of the act perceived, and may not be, but because of the good nature, honesty they still d

The olfactory critical period is determined by activity-dependent Sema7A/PlxnC1 signaling within glomeruli

In mice, early exposure to environmental odors affects social behaviors later in life. A signaling molecule, Semaphorin 7A (Sema7A), is induced in the odor-responding olfactory sensory neurons. Plexin C1 (PlxnC1), a receptor for Sema7A, is expressed in mitral/tufted cells, whose dendrite-localization is restricted to the first week after birth. Sema7A/PlxnC1 signaling promotes post-synaptic events and dendrite selection in mitral/tufted cells, resulting in glomerular enlargement that causes an increase in sensitivity to the experienced odor. Neonatal odor experience also induces positive responses to the imprinted odor. Knockout and rescue experiments indicate that oxytocin in neonates is responsible for imposing positive quality on imprinted memory. In the oxytocin knockout mice, the sensitivity to the imprinted odor increases, but positive responses cannot be promoted, indicating that Sema7A/PlxnC1 signaling and oxytocin separately function. These results give new insights into our understanding of olfactory imprinting during the neonatal critical period.

Analysis on the Dynamic Wave Attenuation Properties of Metaconcrete Considering a Quasi-Random Arrangement of Inclusions

The mitigation properties of metaconcrete cast with two types of resonant inclusions are assessed through wave transmission tests. Three cylindric metaconcrete specimens of regular size (20 cm height, 10 cm diameter), containing an equal number of different type of inclusions disposed in a semi-regular lattice, are tested in the longitudinal direction within the sonic range of frequencies. Inclusions, bi-material spheres consisting of a heavy core coated with a soft material, are characterized by a resonant behavior, evaluated numerically with a finite element modal analysis of a unit metaconcrete cell. Each metaconcrete specimen contains six layers consisting of six engineered aggregates of different type. Inclusions are disposed by rotating each layer with respect to the adjacent ones, as so as to create a pseudo-random arrangement. Specimens are excited by a sinusoidal signal of linearly growing frequency, sweeping a range centered at the translational eigenfrequency of the resonant inclusion. A standard plain concrete specimen is used as reference to define a transmissibility coefficient, that facilitates the quantification of the attenuation properties. With respect to plain concrete, all metaconcrete specimens show a marked (up to 80–90%) attenuation of the transmitted signal in proximity of the numerically estimated eigenfrequency of the inclusion. The intensity of the attenuation is weakly dependent on the type of the inclusion, while the frequency where the attenuation is observed depends markedly on the inclusion type. As a very positive quality in the view of practical applications, experimental results confirm that the attenuation effectiveness of metaconcrete is not related to the ordered microstructural arrangement.

A New and Convenient Method to Get Paraffin-Embedded Sections of Tuberculous Bacteria as Positive Quality Controls for Acid-Fast Staining

Background: Acid-fast staining for the detection of Mycobacterium tuberculosis has a high false negative-rate, partly due to it is hard to get a good positive control tissue of acid-fast staining. We aimed to design a simple and convenient method for making positive quality controls for acid-fast staining in paraffin-embedded sections.Methods: Three methods were used to get more tuberculous bacteria, which involving centrifugation, mixing, and culture of tubercle bacilli in pleural fluid, prior to the preparation of paraffin-embedded sections.Results: Culturing tubercle bacilli in pleural fluid proved to be, by far, the best of the three methods, with sufficient bacteria, convenient observation, clear staining, and potential for upscaled production.Conclusions: The application of this method should improve the detection rate of tuberculous bacteria, thus facilitating clinical treatment.

“Thaz how u kno ur dum”

This study analyzes language use among a group of gay men who participate on an online messageboard (OnYourKnees), focused on the attainment of a ‘dumb jock’ identity. Posters align with a series of qualities that largely conform to ideologies of American jock masculinity, but at the same time satirize those ideologies: in particular, many posters view as an integral quality of dumb-jock identity ‘dumbness:’ an unwillingness/inability to engage in scholarly/academic pursuits. The repeated citationality of dumbness as a positive quality creates a distinct identity-type that posters link with erotic desire. Orthographic variation contributes to the attainment and recognition of a jock identity: posters who identify as jocks are more likely to display non-standard American English spelling than those who do not. This study thus highlights the importance of orthographic variation in maintaining distinct identities among local communities, especially in a space where traditional ideologies of masculinity are recontextualized.

Usulan perbaikan kualitas pelayanan penerbitan sertifikat tanah dengan pendekatan Quality Function Deployment

Quality Function Deployment uses a very different approach because it adds value to the product by maximizing positive quality, such as ease of use, pleasure, and luxury. Visible or invisible customer needs will be handled by Quality Function Deployment. Research analysis found 31 service quality attributes, consisting of 10 variables of simplicity, clarity, time certainty, accuracy, security, responsibility, completeness of infrastructure, ease of access, friendly discipline, comfort. There were still 23 House of Quality results that did not meet customer satisfaction that was prioritized for improvement. The priority order of improvement is most important to the requirements of the customers, namely the responsibility of the officer in the work with a relative importance of 26,225 in stage 1 and Making an assessment of the performance of the officer with a relative importance of 18,424 is the highest value for QFD stage 2.

Hume on Pride, Vanity and Society

Pride is a fundamental element in Hume's description of human nature. An important part of the secondary literature on Hume is devoted to this passion. However, no one, as far as I am aware, takes seriously the fact that pride often appears in pairs with vanity. In Book 2 of the Treatise, pride is defined as the passion one feels when society recognizes his connection to a ‘cause’, composed by a ‘subject’ and a (positive) ‘quality’. Conversely, no definition of vanity is provided. Despite Hume's fluctuating vocabulary, I hold that a conceptual difference between pride and vanity exists. To support this claim, I analyse the common features of these two passions, showing that both pride and vanity (a) are indirect passions, (b) are self-regarding passions, and (c) have the same structure. Supported by textual evidence, I then claim that vanity is a desire of reputation, a desire to feel pride, when pride is not (yet) in place, because its cause is only imaginary and not real. Nonetheless, I underscore that, at times, ‘vanity’ means simply pride and call for greater attention on this ongoing oscillation. In conclusion, I explore the implications of this account of vanity for social interactions in Hume's philosophy, which illustrates its intrinsic ambivalence.