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The liquid bridge rupture has attracted much attention in various fields such as powder technology, micro gripping, and wet agglomeration. In present study, an artificial neural network (ANN) model was developed to predict the liquid bridge rupture between two plates, focusing on the rupture distance and the transfer ratio. The initial weights and biases of the ANN model were optimized by the grey wolf optimization algorithm (GWO). The GWO-ANN model prediction is compared with the BP-ANN model prediction. Based on the testing dataset, the mean square error (MSE) and correlation coefficient (R2) of the rupture distance for the optimized GWO-ANN model were calculated as 4.65 × 10− 4 and 0.9586, and that of the transfer ratio was 2.15 × 10− 4 and 0.975, respectively. The effectiveness of the constructed GWO-ANN model for the liquid bridge rupture prediction was verified by experimental investigations. The effect of input parameters including contact angles, stretching speed, liquid volume and liquid viscosity on the rupture was discussed in detail. [ABSTRACT FROM AUTHOR]

In order to reduce the transmission of vertical vibration waves generated by the rail-track system to the station superstructure through the platform columns, a nested vibration isolation column for subway stations is developed. Taking the Financial Island Station of the Xiong'an -- Beijing Daxing International Airport Express Line (Line R1) as research background, a nested steel structure vibration isolation column model is established, and rubber vibration damping columns are set at the intervals of the nested structure. Modal analysis and acceleration transfer rate analysis in the frequency domain are performed. The findings show that: compared with the traditional column, the nested vibration isolation column adds 97 vibration isolation frequencies in the frequency range of 0~200 Hz, achieving vibration isolation effects of more than 60% of the frequencies; fundamental frequency vibration isolation performance will be enhanced by raising the width of the central support, decreasing the radius of the rubber damping body cross-section, and increasing the bottom length-width ratio of the U-shaped nested steel structure. The vibration isolation columns designed mainly with the anisotropic U-shaped nested steel structure can effectively reduce the vertical vibration generated by the rail-track system. [ABSTRACT FROM AUTHOR]

Objective: The current study investigated the immune response of maternal coronavirus disease 2019 (COVID‐19) vaccination and vertical transmission of anti–severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) spike (S) and nucleocapsid (N) proteins. Study design: This retrospective study included pregnant women in Bahrain Defense Force Hospital from March 2021 to September 2021 who were vaccinated with Sinopharm or Pfizer/BioNTech. Testing of anti‐N and ‐S levels from paired samples of maternal and umbilical cord blood was performed at the time of delivery. The immune response to vaccination, association with maternal and fetal factors, and vertical transmission of antibodies were studied. Results: The current study included 79 pregnant women. The median gestational age for those vaccinated with Sinopharm was 28 weeks and those vaccinated with Pfizer was 31 weeks, with 100% of the vaccinated population generating antibodies and showing vertical transmission. The anti‐N and ‐S titers and interval frequencies varied in both vaccinations. The anti‐N and ‐S and transfer ratio statistically correlated with maternal age, gestational age at delivery, latency period, and birth weight of the neonates differently in both vaccines. In addition, the peak level of antibodies and transfer ratios varied. Conclusion: Although variations are exhibited in both types of vaccination, the vaccinated pregnant population generated a significant level of anti‐N and ‐S and showed vertical transmission. Synopsis: Although variations are exhibited in the type of COVID‐19 vaccination, the vaccinated pregnant population generated a significant level of anti‐N and ‐S and showed vertical transmission. [ABSTRACT FROM AUTHOR]

Aiming at the problem of vibration caused by underground high-speed railways, this paper proposes a vibration prediction method based on the multi-point transfer ratio in the frequency domain. The transmission information of vibration signals from the tunnel to the surface was obtained by an in situ hammer excitation test, and the acceleration response near the vibration source was calculated via high-precision vehicle-track coupling analysis and a finite element model of the tunnel. Then, the superposition operation was carried out in consideration of the position change of the train, and the surface vibration response caused by the underground high-speed railway was finally predicted. An in situ vibration test was carried out near an underground high-speed railway line and the measured data were compared with the predicted data. The results demonstrate that the predicted and measured time domain peaks were similar, and the main vibration frequencies were both located in the range of 30–70 Hz. Moreover, the 1/3-octave spectra were also very similar, and the root mean square error of acceleration and the Z vibration level error were less than 1.9%. The comparison results show that the proposed method can be used to predict the vibration response caused by the operation of underground high-speed railways with high precision. [ABSTRACT FROM AUTHOR]

Persistent halogenated organic pollutants (HOPs) are a class of toxic chemicals, which may have adverse effects on fetuses via transplacental transfer from their mothers. Here, we review reported internal exposure levels of various HOPs (organochlorinated pesticides, polychlorinated biphenyls, polybrominated diphenyl ethers, short- and medium-chain chlorinated paraffins, and per- and poly-fluoroalkyl substances) in placenta, and both maternal and umbilical cord sera. We also present analyses of the transplacental transfer and placental distribution characteristics of each class of compounds, and discuss effects of several factors on the transfer and accumulation efficiencies of HOPs, as well as the main mechanisms of HOPs’ transfer across the placental barrier. Reported compound-specific transplacental transfer efficiencies and distribution efficiencies, expressed as umbilical cord:maternal serum and placental:maternal serum concentration ratios (RCM and RPM, respectively), are summarized. Average published RCM values of the HOPs range from 0.24 to 3.08 (lipid-adjusted) and from 0.04 to 3.1 (based on wet weights), and are highest for perfluoroalkylcarboxylates (PFCAs) and tetrabromobisphenol A. Average published RPM values range from 0.14 to 1.02 (lipid-adjusted) and from 0.30 to 1.4 (based on wet weights). The broad RCM and RPM ranges may reflect effects of various factors, inter alia physicochemical properties of HOPs, metabolic capacities of mothers and fetuses, placental maturity, and differential expression of influx/efflux transporters in the placenta. Generally, HOPs’ RCM values decline linearly with molecular size, and are curvilinearly related to solubility. Plasma protein binding affinity and the difference between maternal and fetal metabolic capacities may also affect some HOPs’ transfer efficiencies. HOPs’ molecular size may be influential. Transplacental transport of HOPs likely occurs mostly through passive diffusion, although influx/efflux transporters expressed on maternal and/or fetal sides of the placenta may also facilitate or hinder their transport. Overall, the review highlights clear gaps in our understanding of mechanisms involved in HOPs’ transplacental transport.

With the opening of the Chinese electricity market, as a retailer that provides energy services to consumers, the park-integrated energy system (PIES) not only serves as an effective way to earn benefits and reduce carbon emissions but also impacts the energy consumption characteristics of consumers. The PIES implements this function by adjusting the energy selling price in free energy markets. The pricing mechanism model (P-M model) is established to obtain the energy selling price in the planning and design stages. In this model, the impact of the demand response on the energy configuration and the impact of the changes in energy configuration on the energy cost price are both considered. Additionally, the optimal result ensures that both the consumers and the PIES benefit simultaneously. The reactive demand response zone, which represents a consumer trap, is found in numerical studies. The results indicate the following: (1) from the perspective of P-M model optimization, the benefit exclusive point of the PIES is the optimal solution in the short term; (2) from the perspective of the long-term benefit, the ultimate result in the relationship between the PIES and consumers is that the PIES will share its profits with consumers; in other words, benefit sharing point is the optimal solution for the long term. [ABSTRACT FROM AUTHOR]

Nowadays, there has been some development in micro/nano manufacturing technology, but many micro/nano components have not yet been applied as products in practice. This is because the application of ultra-micro encapsulation technology in the micro/nano field is one of the main obstacles. Ultra-micro encapsulation needs to reach the nL (10-9L) level. However, there are some problems with methods that can achieve nL-level encapsulation currently, such as the amount of adhesive output is uneven and uncontrollable. Therefore, this article proposes an ultra-micro dispensing method based on the principle of liquid transfer, which achieves adhesive transfer at the pL (10-12L) level. A way to ascertain the liquid's transfer state based on the transfer ratio is proposed in response to the difficulty in determining the stretching speed when changes in the transfer state at the pL level. The roles of Ca , receding contact angle, and initial distance in various transfer states were investigated, and a prediction formula for the transfer ratio was derived based on the influence of three physical parameters on the transfer ratio. Verification has confirmed that the discrepancy between the predicted transfer ratio and the actual transfer ratio doesn't surpass 3%. [ABSTRACT FROM AUTHOR]

This paper proposes a new vibration isolation mounting system, with spherical balls and vertical spring dampers, that provides seismic protection from horizontal and vertical ground excitation. To characterize the system, nonlinear governing equations are derived by considering the kinematics and interaction forces of the structures, and the dynamic characteristics of the design parameters are investigated by numerical analysis. The condition of contact stability for sustaining continuous friction of the isolation device is discussed, along with the design parameters. The vibration transfer characteristics are analyzed for the displacement transfer ratio obtained for the design parameters satisfying the sustainable contact condition, when the base is harmonically excited. The results confirm that the relative motion occurrence satisfies the conditional expression, and a jump in which the transfer ratio suddenly increases at a specific frequency is identified. Finally, design variables that are suitable for the horizontal and vertical acceleration of the El Centro earthquake are set, and a simulation confirms the vibration reduction effect in both the horizontal and vertical motions. [ABSTRACT FROM AUTHOR]

Implementations of the variational method in transformer bridges with inductively coupled arms and in logometric bridges based on an operational amplifier with high amplification factor are described. It is shown that through the use of the variational method in transformer bridges it is possible to eliminate the influence of the basic error sources – impedances in connecting cables and transformer windings – and, in logometric bridges, by means of this method, eliminate the effect of the finite amplification factor of the operational amplifier and its input impedance on the measurement results. Theoretical and experimental investigations have shown that the measurement error may be reduced 100- and 1000-fold through the use of the variational method. Metrological data from impedance meters developed with the use of variational methods are presented. [ABSTRACT FROM AUTHOR]

The variational method of increasing the precision of instruments for the measurement of the impedance parameters is considered. The method is based on variations of the coefficients of influence of the sources of an error on the result of measurements. It is shown that each variation of an influence coefficient of a particular source of error is accompanied by a corresponding measurement of the input quantity. A solution of the system of equations that describes these measurements and that makes it possible to obtain an exact result is presented. Devices used for different purposes constructed on the basis of the variational method are described. [ABSTRACT FROM AUTHOR]

Aflatoxin M1 (AFM1) is a hydroxylated metabolite of aflatoxin B1 (AFB1) that can be excreted in milk of cows after consuming contaminated feed. The aim of this study consisted of a field monitoring to assess the contamination levels of AFB1 in 60 feed samples from two feeding systems for high-yielding dairy cows and of AFM1 in the corresponding raw milk samples. The aflatoxins were analyzed by in-house validated methods based on high-performance liquid chromatography (HPLC) with fluorescence detection. AFB1 was detected in 55% of feed samples (mean 0.61 μg/kg, with 2 samples exceeding the European Union (EU) maximum level set at 5 μg/kg), with greater incidence and concentration in compound feed than in unifeed rations (p < 0.05). AFM1 was detected in 38.3% milk samples (mean 12.6 ng/kg, with 5 samples exceeding the EU maximum level set at 50 ng/kg), with a higher occurrence in milk of cows fed compound feed, as well as in spring milk compared to that produced in winter. The overall transfer ratio of aflatoxins from feed to milk was 3.22%, being higher in cows fed with compound feed and in spring milkings. In a selection of positive matched samples (n = 22), the ratio AFM1/AFB1 exceeded the European Food Safety Authority (EFSA) estimated 6% threshold for high-yielding dairy cows.

Food-producing animals represent one of the sources of antibiotic resistant commensal bacteria. There is an increasing awareness that these bacteria might have the potential to transfer their resistance genes to other (pathogenic) bacteria. In this study, 50 commensal Escherichia coli strains originating from food-producing animals and resistant to the “highest priority, critically important antibiotics” cefotaxime and/or ciprofloxacin, were selected for further characterization. For each strain (i) an antibiogram, (ii) the phylogenetic group, (iii) plasmid replicon type, (iv) presence and identification of integrons, and (v) antibiotic resistance transfer ratios were determined. Forty-five of these strains were resistant to 5 or more antibiotics, and 6 strains were resistant to 10 or more antibiotics. Resistance was most common to ampicillin (100%), sulfamethoxazole, ciprofloxacin (82%), trimethoprim, tetracycline (74%), cefotaxime, (70%) and ceftazidime (62%). Phylogenetic groups A (62%) and B1 (26%) were most common, followed by C (8%) and E (4%). In 43 strains, more than 1 replicon type was detected, with FII (88%), FIB (70%), and I1 (48%) being the most encountered types. Forty strains, positive for integrons, all harbored a class I integron and seven of them contained an additional class II integron. No class III integrons were detected. The antibiotic resistance transfer was assessed by liquid mating experiments. The transfer ratio, expressed as the number of transconjugants per recipient, was between 10−5 and 100 for cefotaxime resistance and between 10−7 and 10−1 for ciprofloxacin resistance. The results of the current study prove that commensal E. coli in food-production animals can be a source of multiple resistance genes and that these bacteria can easily spread their ciprofloxacin and cefotaxime resistance. [ABSTRACT FROM AUTHOR]

This paper proposes a new vibration isolation mounting system, with spherical balls and vertical spring dampers, that provides seismic protection from horizontal and vertical ground excitation. To characterize the system, nonlinear governing equations are derived by considering the kinematics and interaction forces of the structures, and the dynamic characteristics of the design parameters are investigated by numerical analysis. The condition of contact stability for sustaining continuous friction of the isolation device is discussed, along with the design parameters. The vibration transfer characteristics are analyzed for the displacement transfer ratio obtained for the design parameters satisfying the sustainable contact condition, when the base is harmonically excited. The results confirm that the relative motion occurrence satisfies the conditional expression, and a jump in which the transfer ratio suddenly increases at a specific frequency is identified. Finally, design variables that are suitable for the horizontal and vertical acceleration of the El Centro earthquake are set, and a simulation confirms the vibration reduction effect in both the horizontal and vertical motions.

With the opening of the Chinese electricity market, as a retailer that provides energy services to consumers, the park-integrated energy system (PIES) not only serves as an effective way to earn benefits and reduce carbon emissions but also impacts the energy consumption characteristics of consumers. The PIES implements this function by adjusting the energy selling price in free energy markets. The pricing mechanism model (P-M model) is established to obtain the energy selling price in the planning and design stages. In this model, the impact of the demand response on the energy configuration and the impact of the changes in energy configuration on the energy cost price are both considered. Additionally, the optimal result ensures that both the consumers and the PIES benefit simultaneously. The reactive demand response zone, which represents a consumer trap, is found in numerical studies. The results indicate the following: (1) from the perspective of P-M model optimization, the benefit exclusive point of the PIES is the optimal solution in the short term; (2) from the perspective of the long-term benefit, the ultimate result in the relationship between the PIES and consumers is that the PIES will share its profits with consumers; in other words, benefit sharing point is the optimal solution for the long term.

To solve the problem of calculating the power circulation and efficiency, the mechanical transmission cycles are reform the notion of efficiency. Using the principle of virtual velocities presented a demonstration to calculate power flux indicator. Finally, examples of the method for calculation of differential type mechanisms.

Concentrations of Cd, Hg, Pb, Cr, Fe, Co, Ni, Cu, Zn, Mo and As were determined in soils and leaves of plants from refuse dumpsites and background soils in two cities, a municipality and a rural community in Ghana, using a ThermoFinnigan Element 2 high resolution inductively coupled plasma mass spectrometric (HR-ICP-MS) instrument. The refuse dump soils were classified between 'Uncontaminated to Moderate' and 'Strongly Contaminated'. Pollution levels for Cd (Igeo = 2.06-2.40) and Zn (Igeo = 2.95-3.36) were higher than of the other metals. The refuse dump soil from the rural community was the least polluted with the metals. Fe and Ni loads in plants from the refuse dump soils in the cities and the municipality were beyond the normal ranges of 40-500 µg/g (Fe) and 0.02-5.00 µg/g (Ni). Transfer ratios for Cd, Hg, Cu, Zn and Pb and Fe of plants from the background soils were higher than those from the refuse dump soils, which might be due to the higher levels of organic matter, pH, phosphate, Ca and Mg in the refuse dump soils.

Tropane alkaloids (TAs) are toxic anticholinergic compounds that appear due to accidental contamination of foods with TA-producing plants. Atropine and scopolamine are the most common TAs and their maximum levels in certain foodstuffs have been recently regulated, including food supplements. TAs occurrence in commercial products and the transfer ratio to herbal infusions prepared from contaminated spices are of interest for exposure assessment of consumers. In this study, the occurrence of atropine and scopolamine was investigated in a total of 51 commercial spices of 6 types (ginger, cloves, fennel, cumin, aniseed, coriander) and a mix of spices and herbs (curry) purchased in Portugal (19 samples) and Spain (32 samples) in 2021. Results evidenced that more than half of the samples analysed (67%) were contaminated with one or both analytes. Fennel, cloves and coriander showed the highest concentrations ranging between 5-31 μg/kg, 8–28 μg/kg and 5–45 μg/kg, respectively, for the sum of atropine and scopolamine. On the other hand, the transfer ratio of the target analytes found in four naturally contaminated fennel samples was studied. Infusions were prepared according to International Standard ISO 3103 protocol, and a transfer ratio between 64 and 88% for atropine and between 47 and 57% for scopolamine was found. • Atropine and scopolamine content in spices relevant for exposure assessment of consumers. • 67% of 51 samples of spices contaminated with one or both analytes. • Highest contamination levels detected in fennel, cloves and coriander. • Transfer ratios to herbal infusions: 64–88% for atropine and 47–57% for scopolamine. [ABSTRACT FROM AUTHOR]

Beeswax is known to have a high capacity to accumulate different contaminants due to its fat-soluble properties. Many surveys in Europe and the USA have shown high levels of contamination in beeswax especially with acaricides used for varroa treatment. In this study, we investigated the transfer pathways of various active substances from beeswax into different matrices under field conditions. Honey, bee bread, larvae, and pupae samples were collected 6–8 weeks after building the experimental colonies on different charges of wax foundations. Identification and quantification of the target substances were performed with an established and validated multi-residue method using LC-MS/MS and GC-MS systems. Nine out of 19 active substances in wax could be detected in the analyzed matrices. Our results confirm the migration of different contaminants from wax into different bee matrices including honey, bee bread, and bee brood. The concentration of detected residues in the different matrices was significantly increased by increasing residue concentration in wax. Therefore, the maximum detected residues in the matrices were almost in wax containing high residual concentrations. Bee bread can be considered as the most important matrix due to relatively high detected concentrations and transfer ratios of the most contaminants. A significant effect of the lipophilicity of active substances on the transfer ratio into bee bread was found, which means that increasing the Log P values has positive effects on the transfer ratio. In conclusion, our results provide the first detailed information regarding the migration of active substances from wax into various matrices under realistic field conditions and are fundamentally important for assessing potential exposure and risks for honey bees. [Display omitted] • Detection of 9 out of 19 active substances in wax in honey, bee bread and brood. • The higher the residues in wax the higher the residues in analyzed matrices. • Bee bread is the most important matrix related to the migration from wax. • Significant effect of the lipophilicity of active substances on the transfer ratio. [ABSTRACT FROM AUTHOR]

Buses and metros are two main public transit modes, and these modes are crucial components of sustainable transportation systems. Promoting reciprocal integration between bus and metro systems requires a deep understanding of the effects of multiple factors on transfers among integrated public transportation transfer modes, i.e., metro-to-bus and bus-to-metro. This study aims to reveal the determinants of the transfer ratio between bus and metro systems and quantify the associated impacts. The transfer ratio between buses and metros is identified based on large-scale transaction data from automated fare collection systems. Meanwhile, various influencing factors, including weather, socioeconomic, the intensity of business activities, and built environment factors, are obtained from multivariate sources. A multivariate regression model is used to investigate the associations between the transfer ratio and multiple factors. The results show that the transfer ratio of the two modes significantly increases under high temperature, strong wind, rainfall, and low visibility. The morning peak hours attract a transfer ratio of up to 57.95%, and the average hourly transfer volume is 0.94 to 1.38 times higher at this time than in other periods. The intensity of business activities has the most significant impact on the transfer ratio, which is approximately 1.5 to 15 times that of the other independent variables. Moreover, an adaptative geographically weighted regression is utilized to investigate the spatial divergences of the influences of critical factors on the transfer ratio. The results indicate that the impact of a factor presents spatial heterogeneity and even shows opposite effects (in terms of positive and negative) on the transfer ratio in different urban contexts. For example, among the related socioeconomic variables, the impact of the housing price on the downtown transfer ratio is larger than that in the suburbs. Crowd density positively influences the transfer ratio at most stations in the northern region, whereas it shows negative results in the southern region. These findings provide valuable insights for public transportation management and promote the effective integration of bus and metro systems to provide enhanced transfer services. • Estimating the transfer ratio of different modes based on large-scale smartcard data. • Revealing the determinants of the transfer ratio and quantifying their impacts. • Disclosing the spatial heterogeneity in the transfer ratio. • Investigating the spatial divergences of critical factors by geographically weighted regression model. [ABSTRACT FROM AUTHOR]

In order to evaluate the isolation efficiency of shock isolation system using energy method, two degrees of freedom mechanical model of shock isolation system consisting of human body and protective structure was introduced. The energy responses of the model due to the excitation of explosion and shock wave were solved. A new evaluation method of shock isolation efficiency was proposed based on the energy transferred to body, which was named the energy transfer ratio. By inputting the half-sine impulse acceleration composed of different peak values and duration time, the energy responses, acceleration transfer ratio and energy transfer ratio of the two degrees of freedom shock isolation system were simulated. According to the results of many numerical examples, the relationship of input and output was studied. The influence rules of the input total energy on the isolation efficiency were obtained. Numerical results illustrate that energy analysis method can reflect the inherent characteristic of the shock isolation system. [ABSTRACT FROM AUTHOR]

The concentration of five trace elements Cr, As, Pb, Rb and Sr in seven medicinal plants Garcinia indica, Ficus benghalensis, Flacartia Montana, Nyctanthes arbor- tristis, Morinda citrifolia, Ficus recemosa, Barringtonia acutangula and associated soils were analyzed using ICP-MS. In plant the elemental concentrations of Cr, Pb, Rb and Sr vary widely and in soil the elemental concentrations of Cr, As and Sr showed wide variation. Selective enrichment of elements Rb and Sr was observed in some plants. The soil to plant transfer ratio was significant for Sr. The results of these systematic investigations are presented and discussed in this paper. [ABSTRACT FROM AUTHOR]