Background Non-physician clinicians (NPCs) providing services in functionally private markets account for a large share of the workforce in the primary care system in many low-income and middle-income countries. Although regular in-service training is believed to be crucial to updating NPCs’ professional knowledge, skills, and practices, participation rates are often low. Low participation may result from the “credence good” nature of the market for primary care: if patients are unable to observe quality improvements from training, NPCs have weaker incentives to participate. Empirical evidence is limited on the relationship between market competition and NPC participation in-service training as well as how participation varies with the type of training available. Methods The study uses a dataset of 301 NPCs from three prefectures in Yunnan, a province in southwest China, collected in July 2017. Logistic regression is used to estimate the relationship between competition and NPC’s participation in in-service training. We assess the relationship between participation and both the quantity of competition (number of competitors in the same village and surrounding villages) and the quality of competition (proxied using characteristics of competing clinicians). Results In 2016, nearly two thirds of NPCs participated in face-to-face or web-based in-service trainings at least once. Specifically, 58 percent of NPCs participated in face-to-face in-service trainings, and 24 percent of NPCs participated in web-based in-service trainings. The quantity of competitors is unrelated to participation in in-service training. The quality of competition is not related to face-to-face training but has a significant positive relationship with participation in web-based training. Conclusions Web-based trainings may be a better approach to increase NPC skills in developing country primary care markets.;The study uses a dataset of 301 NPCs from three prefectures in Yunnan, a province in southwest China, collected in July 2017. Logistic regression is used to estimate the relationship between competition and NPC's participation in in-service training. We assess the relationship between participation and both the quantity of competition (number of competitors in the same village and surrounding villages) and the quality of competition (proxied using characteristics of competing clinicians). In 2016, nearly two thirds of NPCs participated in face-to-face or web-based in-service trainings at least once. Specifically, 58 percent of NPCs participated in face-to-face in-service trainings, and 24 percent of NPCs participated in web-based in-service trainings. The quantity of competitors is unrelated to participation in in-service training. The quality of competition is not related to face-to-face training but has a significant positive relationship with participation in web-based training. Web-based trainings may be a better approach to increase NPC skills in developing country primary care markets.;
Formaldehyde (HCHO) is one of the most important intermediate products of atmospheric photochemical reactions and is also a radical source that promotes ozone formation. Given its high solubility, HCHO is likely to exist in particulate form. In this work, gaseous HCHO (HCHOg) and particulate HCHO (HCHOp) were separated and collected by a rotating wet annular denude (RWAD) and an aerosol growth chamber-coil aerosol cooler (AC). The collected HCHO from the RWAD and AC are measured by two online Hantzsch method-based formaldehyde analyzers. The comprehensive campaign was held in the Yangtze River Delta of China from 15 May to 18 June 2018, which is during the harvest season. Several biomass burning events were identified by using acetonitrile as a tracer. During the period influenced by biomass burning, the mixing ratios of HCHOg and HCHOp were respectively 122% and 231% higher than those during other time periods. The enhancement ratio of HCHOg to acetonitrile obtained from this work generally agrees with those from the existing literature. Biomass burning contributed 14.8% to HCHOg, but the abundant freshly discharged precursors it emitted greatly promoted the secondary production of HCHOg. We suggest that the high concentration of HCHOp during the biomass burning period was from uptake of HCHOg by aerosols during their transportation; the liquid state particles are conducive to HCHOg uptake. High relative humidity, a low particle rebound fraction f, as well as low temperatures may result in higher uptake coefficient values.
Formaldehyde (HCHO) is one of the most important intermediate products of atmospheric photochemical reactions and is also a radical source that promotes ozone formation. Given its high solubility, HCHO is likely to exist in particulate form. In this work, gaseous HCHO (HCHOg) and particulate HCHO (HCHOp) were separated and collected by a rotating wet annular denude (RWAD) and an aerosol growth chamber-coil aerosol cooler (AC). The collected HCHO from the RWAD and AC are measured by two online Hantzsch method-based formaldehyde analyzers. The comprehensive campaign was held in the Yangtze River Delta of China from 15 May to 18 June 2018, which is during the harvest season. Several biomass burning events were identified by using acetonitrile as a tracer. During the period influenced by biomass burning, the mixing ratios of HCHOg and HCHOp were respectively 122% and 231% higher than those during other time periods. The enhancement ratio of HCHOg to acetonitrile obtained from this work generally agrees with those from the existing literature. Biomass burning contributed 14.8% to HCHOg, but the abundant freshly discharged precursors it emitted greatly promoted the secondary production of HCHOg. We suggest that the high concentration of HCHOp during the biomass burning period was from uptake of HCHOg by aerosols during their transportation; the liquid state particles are conducive to HCHOg uptake. High relative humidity, a low particle rebound fraction f, as well as low temperatures may result in higher uptake coefficient values.
Formaldehyde (HCHO) is one of the most important intermediate products of atmospheric photochemical reactions and is also a radical source that promotes ozone formation. Given its high solubility, HCHO is likely to exist in particulate form. In this work, gaseous HCHO (HCHOg) and particulate HCHO (HCHOp) were separated and collected by a rotating wet annular denude (RWAD) and an aerosol growth chamber–coil aerosol cooler (AC). The collected HCHO from the RWAD and AC are measured by two online Hantzsch method-based formaldehyde analyzers. The comprehensive campaign was held in the Yangtze River Delta of China from 15 May to 18 June 2018, which is during the harvest season. Several biomass burning events were identified by using acetonitrile as a tracer. During the period influenced by biomass burning, the mixing ratios of HCHOg and HCHOp were respectively 122% and 231% higher than those during other time periods. The enhancement ratio of HCHOg to acetonitrile obtained from this work generally agrees with those from the existing literature. Biomass burning contributed 14.8% to HCHOg, but the abundant freshly discharged precursors it emitted greatly promoted the secondary production of HCHOg. We suggest that the high concentration of HCHOp during the biomass burning period was from uptake of HCHOg by aerosols during their transportation; the liquid state particles are conducive to HCHOg uptake. High relative humidity, a low particle rebound fraction f, as well as low temperatures may result in higher uptake coefficient values.
Nitrous oxide emission factors (N2O-EF, percentage of N2O–N emissions arising from applied fertilizer N) for cropland emission inventories can vary with agricultural management, soil properties and climate conditions. Establishing a regionally-specific EF usually requires the measurement of a whole year of N2O emissions, whereas most studies measure N2O emissions only during the crop growing season, neglecting emissions during non-growing periods. However, the difference in N2O-EF (ΔEF) estimated using measurements over a whole year (EFwy) and those based on measurement only during the crop-growing season (EFgs) has received little attention. Here, we selected 21 studies including both the whole-year and growing-season N2O emissions under control and fertilizer treatments, to obtain 123 ΔEFs from various agroecosystems globally. Using these data, we conducted a meta-analysis of the ΔEFs by bootstrapping resampling to assess the magnitude of differences in response to management-related and environmental factors. The results revealed that, as expected, the EFwy was significantly greater than the EFgs for most crop types. Vegetables showed the largest ΔEF (0.19%) among all crops (0.07%), followed by paddy rice (0.11%). A higher ΔEF was also identified in areas with rainfall ≥600 mm yr−1, soil with organic carbon ≥1.3% and acidic soils. Moreover, fertilizer type, residue management, irrigation regime and duration of the non-growing season were other crucial factors controlling the magnitude of the ΔEFs. We also found that neglecting emissions from the non-growing season may underestimate the N2O-EF by 30% for paddy fields, almost three times that for non-vegetable upland crops. This study highlights the importance of the inclusion of the non-growing season in the measurements of N2O fluxes, the compilation of national inventories and the design of mitigation strategies.
Reservoirs play a vital role in the control and management of surface water resources. However, the long water residence time in the reservoir potentially increases the storage and accumulation of antibiotic resistant genes (ARGs). The full profiles and potential health risks of antibiotic resistomes in reservoirs are largely unknown. In this study, we investigated the antibiotic resistomes of water and sediment during different seasons in the Danjiangkou Reservoir, which is one of the largest reservoirs in China, using a metagenomic sequencing approach. A total of 436 ARG subtypes belonging to 20 ARG types were detected from 24 water and 18 sediment samples, with an average abundance of 0.138 copies/cell. The overall ARG abundance in the sediment was higher than that in the water, and bacitracin and vancomycin resistance genes were the predominant ARG types in the water and sediment, respectively. The overall ARG abundance in the dry season was higher than that in the wet season, and a significant difference in ARG subtype compositions was observed in water, but not in the sediment, between the different seasons. The potential horizontal gene transfer frequency in the water was higher than that in the sediment, and the ARGs in water mainly came from the sediment upstream of the reservoir. The metagenomic assembly identified 14 contigs as ARG-carrying pathogens including Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa, and 3 of 14 carried virulence factors. Overall, the potential public health risks posed by resistomes in the water of the Danjiangkou Reservoir were higher in the dry season than in the wet season. Based on these results, strategies including sediment control and pathogen monitoring are suggested for water safety management in drinking water reservoirs.
Reservoirs play a vital role in the control and management of surface water resources. However, the long water residence time in the reservoir potentially increases the storage and accumulation of antibiotic resistant genes (ARGs). The full profiles and potential health risks of antibiotic resistomes in reservoirs are largely unknown. In this study, we investigated the antibiotic resistomes of water and sediment during different seasons in the Danjiangkou Reservoir, which is one of the largest reservoirs in China, using a metagenomic sequencing approach. A total of 436 ARG subtypes belonging to 20 ARG types were detected from 24 water and 18 sediment samples, with an average abundance of 0.138 copies/cell. The overall ARG abundance in the sediment was higher than that in the water, and bacitracin and vancomycin resistance genes were the predominant ARG types in the water and sediment, respectively. The overall ARG abundance in the dry season was higher than that in the wet season, and a significant difference in ARG subtype compositions was observed in water, but not in the sediment, between the different seasons. The potential horizontal gene transfer frequency in the water was higher than that in the sediment, and the ARGs in water mainly came from the sediment upstream of the reservoir. The metagenomic assembly identified 14 contigs as ARG-carrying pathogens including Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa, and 3 of 14 carried virulence factors. Overall, the potential public health risks posed by resistomes in the water of the Danjiangkou Reservoir were higher in the dry season than in the wet season. Based on these results, strategies including sediment control and pathogen monitoring are suggested for water safety management in drinking water reservoirs.
Polarization-based passive millimeter-wave imaging has been applied in several applications, including material clustering, pattern recognition, and target detection. We present here a general formulation of a metal target detection method called dual linear polarization discriminator (DLPD), utilizing passive millimeter-wave polarimetric imagery. Several potential discriminators are defined, and linear polarization difference ratio (LPDR) is selected and proposed to be a new feature discriminator that is sensitive to material composition and able to reduce ambient radiation effects when detecting target with different material and shape. Furthermore, the detection criterion is verified utilizing the threshold values determined by a statistical analysis of LPDR. Outdoor experiments demonstrate that the proposed detection method is highly effective for detecting a metal target in a complex background.
Average bioequivalence tests are used in clinical trials to determine whether a generic drug has the same effect as an original drug in the population. For highly variable drugs whose intra-subject variances of direct drug effects are high, extra criteria are needed in bioequivalencestudies. Currently used average bioequivalence tests for highly variable drugs recommended by the European Medicines Agency and the US Food and Drug Administration use sample estimators in the null hypotheses of interest. They cannot control the empirical type I error rate, so the consumer's risk is higher than the predetermined level. In this paper, we propose two new statistically sound methods that can control the empirical type I error rate without involving any sample estimators in the null hypotheses. In the proposed methods, we consider the average level of direct drug effects and the intra-subject variance of the direct drug effects. The first proposed method tests the latter parameter first to determine whether a product should be regarded as a highly variable drug, and then tests the former using corresponding bioequivalence limits. The second proposed method tests these two parameters simultaneously to capture the bioequivalence region. Extensive simulations are done to compare these methods. The simulation results show that the proposed methods have good performance on controlling the empirical type I error rate. The proposed methods are useful for pharmaceutical manufacturers and regulators.
Reverse osmosis (RO) technology is promising in the sustainable production of fresh water. However, expansion of RO use has been hindered by membrane fouling, mainly inorganic fouling known as scaling. Although membrane mineral scaling by chemical means have been investigated extensively, mineral scaling triggered by microbial activity has been largely neglected. In this study, the simultaneous biomineralization of CaCO3 and CaSO4 in the presence of three different microbial communities from fresh water, wastewater, and seawater was investigated. In the presence of either 13 or 79 mM of Ca2+ and SO42- in the media, the fresh water microbial community produced calcite/vaterite and vaterite/gypsum, respectively; the wastewater community produced vaterite and vaterite/gypsum, respectively; and the seawater community produced aragonite in both conditions. The results showed that the concentration of salts and the microbial composition influence the types of precipitates produced. The mechanisms of crystal formation of CaCO3 and gypsum by these communities were also investigated by determining the need for metabolic active cells, the effect of a calcium channel blocker, and the presence of extracellular polymeric substances (EPS). The results showed that metabolically active cells can lead to production of EPS and formation of Ca2+ gradient along the cells through calcium channels, which will trigger formation of biominerals. The prevention of biomineralization by these consortia was also investigated with two common polymeric RO antiscalants, i.e. polyacrylic acid (PAA) and polymaleic acid (PMA). Results showed that these antiscalants do not prevent the formation of the bio-precipitates suggesting that novel approaches to prevent biomineralization in RO systems still needs to be investigated.
Thermography detects surface temperature and subsurface thermal activity of an object based on the Stefan-Boltzmann law. Impacts of the technology would be more far-reaching with finer thermal sensitivity, called noise-equivalent differential temperature (NEDT). Existing efforts to advance NEDT are all focused on improving registration of radiation signals with better cameras, driving the number close to the end of the roadmap at 20 to 40 mK. In this work, we take a distinct approach of sensitizing surface radiation against minute temperature variation of the object. The emissivity of the thermal imaging sensitizer (TIS) rises abruptly at a preprogrammed temperature, driven by a metal-insulator transition in cooperation with photonic resonance in the structure. The NEDT is refined by over 15 times with the TIS to achieve single-digit millikelvin resolution near room temperature, empowering ambient thermography for a broad range of applications such as in operando electronics analysis and early cancer screening.
