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Rice is widely grown in rainfed lowlands during the wet season in the Mekong region. Limited nutrient availability is a common constraint on crop yield, and the optimal rate of fertilizer application depends on the soil type. The objective of our study was to evaluate rice productivity and the economic feasibility of various nutrient management regimes in Cambodia. We conducted field experiments on three soil types (Prey Khmer, Prateah Lang, and Toul Samroung, equivalent to Psamments, Plinthustalfs, and Endoaqualfs, respectively) in four provinces (Battambang, Kampong Thom, Pursat, and Siem Reap) during the 2016 and 2017 wet seasons to compare nine (2016) and seven (2017) N–P–K combinations. Grain yield ranged from 0.9 to 4.8 t ha−1 in 2016 and from 1.0 to 5.2 t ha−1 in 2017, depending on soil type and nutrient management. The Prey Khmer soil contained around 80% sand, and rice yield responded most weakly to nutrient management. The moderate fertilizer input in the current soil-specific recommendation was effective on this soil type. However, on more fertile soils with a higher clay content and a higher cation-exchange capacity (Toul Samroung and Prateah Lang), an additional 20 kg N ha−1 combined with adding 15 kg ha−1 of P2O5 or 20 kg ha−1 of K2O significantly increased yield and economic return. Although P and K use during Cambodia’s wet season is uncommon, our results demonstrate the importance of these nutrients in improving the country’s rice production.
We introduce CRYSTAL, a multi-agent AI system for crystal-structure phase mapping. CRYSTAL is the first system that can automatically generate a portfolio of physically meaningful phase diagrams for expert-user exploration and selection. CRYSTAL outperforms previous methods to solve the example Pd-Rh-Ta phase diagram, enabling the discovery of a mixed-intermetallic methanol oxidation electrocatalyst. The integration of multiple data-knowledge sources and learning and reasoning algorithms, combined with the exploitation of problem decompositions, relaxations, and parallelism, empowers AI to supersede human scientific data interpretation capabilities and enable otherwise inaccessible scientific discovery in materials science and beyond.
Previously known to form only under high pressure synthetic conditions, here we report that the T′-type 214-structure cuprate based on the rare earth atom Tb is stabilized for ambient pressure synthesis through partial substitution of Pd for Cu. The new material is obtained in purest form for mixtures of nominal composition Tb1.96Cu0.8Pd0.2O4. The refined formula, in orthorhombic space group Pbca, with a = 5.5117(1) Å, b = 5.5088(1) Å, and c = 11.8818(1) Å, is Tb2Cu0.83Pd0.17O4. An incommensurate structural modulation is seen along the a axis by electron diffraction and high resolution imaging. Magnetic susceptibility measurements reveal long-range antiferromagnetic ordering at 7.9 K, with a less pronounced feature at 95 K; a magnetic moment reorientation transition is observed to onset at a field of approximately 1.1 T at 3 K. The material is an n-type semiconductor.
Simulation models are used widely in pharmacology, epidemiology and health economics (HEs). However, there have been no attempts to incorporate models from these disciplines into a single integrated model. Accordingly, we explored this linkage to evaluate the epidemiological and economic impact of oseltamivir dose optimisation in supporting pandemic influenza planning in the USA. An HE decision analytic model was linked to a pharmacokinetic/pharmacodynamics (PK/PD) – dynamic transmission model simulating the impact of pandemic influenza with low virulence and low transmissibility and, high virulence and high transmissibility. The cost-utility analysis was from the payer and societal perspectives, comparing oseltamivir 75 and 150 mg twice daily (BID) to no treatment over a 1-year time horizon. Model parameters were derived from published studies. Outcomes were measured as cost per quality-adjusted life year (QALY) gained. Sensitivity analyses were performed to examine the integrated model's robustness. Under both pandemic scenarios, compared to no treatment, the use of oseltamivir 75 or 150 mg BID led to a significant reduction of influenza episodes and influenza-related deaths, translating to substantial savings of QALYs. Overall drug costs were offset by the reduction of both direct and indirect costs, making these two interventions cost-saving from both perspectives. The results were sensitive to the proportion of inpatient presentation at the emergency visit and patients’ quality of life. Integrating PK/PD–EPI/HE models is achievable. Whilst further refinement of this novel linkage model to more closely mimic the reality is needed, the current study has generated useful insights to support influenza pandemic planning.
We investigated the first presence of qnrA among Shigella sonnei clinical isolates in Jiangsu Province, China. The qnrA-positive isolates coexisted with the mutation in gyrA at codon 83, these isolates were resistant to nalidixic acid and 22·2% (2 of 9) of them were resistant to norfloxacin.
We compute the outcomes of close encounters between a binary and a single black holes including the effects of gravitational radiation reaction. All masses of individual black holes are assumed to be 1 M⊙. We found that merger of two black holes takes place during the encounters in some cases. Thus the gravitational radiation can act as a mechanism for the dissipation of energy of a cluster mainly composed of 10 M⊙ black holes which are produced by the evolution of high mass stars. The merger probability depends on many parameters in a complex way. Our preliminary calculations show that about 10% of the strong encounters (i.e., rp ∼ a) between a binary of hardness 100 and a single lead to mergers of two black holes in the stellar system of one-dimensional velocity σ = 100 km/s.
Repeat rectal chlamydia infection is common in men who have sex with men (MSM) following treatment with 1 g azithromycin. This study describes the association between organism load and repeat rectal chlamydia infection, genovar distribution, and efficacy of azithromycin in asymptomatic MSM. Stored rectal chlamydia-positive samples from MSM were analysed for organism load and genotyped to assist differentiation between reinfection and treatment failure. Included men had follow-up tests within 100 days of index infection. Lymphogranuloma venereum and proctitis diagnosed symptomatically were excluded. Factors associated with repeat infection, treatment failure and reinfection were investigated. In total, 227 MSM were included – 64 with repeat infections [28·2%, 95% confidence interval (CI) 22·4–34·5]. Repeat positivity was associated with increased pre-treatment organism load [odds ratio (OR) 1·7, 95% CI 1·4–2·2]. Of 64 repeat infections, 29 (12·8%, 95% CI 8·7–17·8) were treatment failures and 35 (15·4%, 95% CI 11·0–20·8) were reinfections, 11 (17·2%, 95% CI 8·9–28·7) of which were definite reinfections. Treatment failure and reinfection were both associated with increased load (OR 2·0, 95% CI 1·4–2·7 and 1·6, 95% CI 1·2–2·2, respectively). The most prevalent genovars were G, D and J. Treatment efficacy for 1 g azithromycin was 83·6% (95% CI 77·2–88·8). Repeat positivity was associated with high pre-treatment organism load. Randomized controlled trials are urgently needed to evaluate azithromycin's efficacy and whether extended doses can overcome rectal infections with high organism load.
Virtual reality surgical simulation of mastoidectomy is a promising training tool for novices. Final-product analysis for assessing novice mastoidectomy performance could be limited by a peak or ceiling effect. These may be countered by simulator-integrated tutoring.
Twenty-two participants completed a single session of self-directed practice of the mastoidectomy procedure in a virtual reality simulator. Participants were randomised for additional simulator-integrated tutoring. Performances were assessed at 10-minute intervals using final-product analysis.
In all, 45.5 per cent of participants peaked before the 60-minute time limit. None of the participants achieved the maximum score, suggesting a ceiling effect. The tutored group performed better than the non-tutored group but tutoring did not eliminate the peak or ceiling effects.
Timing and adequate instruction is important when using final-product analysis to assess novice mastoidectomy performance. Improved real-time feedback and tutoring could address the limitations of final product based assessment.
We derive zphot for sources in the entire (~0.4 deg2) H-HDF-N field with the EAzY code, based on PSF-matched broad-band (U band to IRAC 4.5 μm) photometry. Our catalog consists of a total of 131,678 sources. We find σNMAD = 0.029 for non-X-ray sources. We also classify each object as a star or galaxy through SED fitting. Furthermore, we match our catalog with the 2 Ms CDF-N main X-ray catalog. For the 462 matched non-stellar X-ray sources, we improve their zphot quality (σNMAD = 0.035) by adding three additional AGN templates. We make our photometry and zphot catalog publicly available.
Biomolecules have been traditionally immobilised onto surfaces using wet chemical techniques for various medical applications. Recent decades have seen plasma methods being used to prepare these surfaces through various forms of surface modification, but the direct exposure of biomolecules to plasma has been avoided due to fears that the molecules would be denatured by the energetic plasma species. Recent results are now demonstrating that direct plasma deposition of biomolecule coatings can be achieved. This creates the possibility to directly modify the surface of implants without any form of surface pre-treatment and this opens up the possibility to alter the healing processes. Materials such as collagen, chitosan, catalase and heparin can be effectively deposited onto surfaces with minimal impact on biological performance and without any chemical binders, linkers or impurities. The performance of these materials has been characterised using both in vitro and in vivo methodologies. In a further step, the results of a preclinical trial are presented which reveal that direct deposition of biomolecules onto open wounds can also be achieved and the impact of this on wound healing is measured in an immunocompromised animal model. A non-thermal plasma device was used to deliver collagen on to chronic wounds and the treatment was shown to promote wound closure in a rabbit wound healing model.
We studied the pulmonary toxicity of indium hydroxide (In(OH)3), which is produced during a recycling process of indium-tin oxide (ITO), in comparison with that of ITO or indium oxide (In2O3), two raw materials of flat panel displays. One hundred and forty-four male Wistar rats were intratracheally given equivalent doses of 10 mg/kg indium as In(OH)3, ITO, or In2O3 particles, twice a week, for a total of 5 times for 2 weeks. Control rats were given distilled water as a vehicle. After 3 weeks, these rats were serially euthanized, and toxicological effects were determined. Body weight gain was significantly suppressed in the In(OH)3-treated rats compared to that in the control group, but not in the ITO- or In2O3-treated rats. Relative lung weights in all the indium-treated groups significantly increased compared to those in the control group throughout the observation period. Furthermore, lung weights in the In(OH)3 group were significantly higher than those in either the ITO or In2O3 group. Blood indium levels in the In(OH)3-treated rats were much higher, 70- to 200-fold, than those in the In2O3- or ITO-treated rats at each time point. Although the lung indium content decreased gradually during the observation periods, the content in the In(OH)3 group was significantly higher than that in either the ITO or In2O3 group. A histopathological analysis revealed foci indicating a slight to severe pulmonary inflammatory response, including exudation to alveolar spaces, were present in all the indium-treated groups. Interstitial fibrotic proliferation was seen only in the In(OH)3-treated rats. The severity of these lesions in the In(OH)3-treated rats was greater than that in either the ITO- or In2O3-treated rats.
The results of our study clearly demonstrated that In(OH)3 particles caused severe pulmonary toxicity when repeated intratracheal instillations were performed in rats. Furthermore, the toxic potency of In(OH)3 in the lung was much higher than that of ITO and In2O3. Accordingly, the toxicity of In(OH)3 particles should be considered in addition to that of ITO and In2O3 particles when indium exposure occurs.
We studied effects of atmospheric air dielectric barrier discharge plasma irradiation to seeds of radish sprouts on chlorophyll and carotenoid concentrations in their leaves. Plasma irradiation increases chlorophyll concentration under some irradiation conditions, whereas the irradiation has little effects on carotenoid concentration. These results show that plasma irradiation to seeds has influence on cell activities in a selective way.
We have studied multigeneration effects of plasma irradiation to seeds of Arabidopsis thaliana (L.) and Zinnia peruviana (L.) on their growth using a scalable DBD device. Atmospheric plasma irradiation enhances growth of these plants in multi-generations. For Arabidopsis thaliana (L.) in the third generation, the leaf area is 2 times larger than that without plasma irradiation and the stem length is 1.5 times longer than that without plasma. For Zinnia peruviana (L.) in the second generation, the stem length is 2 times longer than that without plasma.
Articular cartilage is prone to degeneration and possesses extremely poor self-healing capacity due to its low cell density and absence of blood vessels. It has extensively reported tissue engineered scaffold can be a promising approach for cartilage repair. However, there still remains an inherent lack of desirable scaffolds that stimulate cartilage regrowth with appropriate functional properties. Therefore, in this study, we develop a biomimetic cartilage substitute comprising of electrospun polycaprolactone (PCL) with cold atmospheric plasma (CAP) modified cell favorable surface and sustained bioactive factor (bovine serum albumin (BSA) or transforming growth factor beta 1 (TGF-β1)) incorporated microspheres inside for improving stem cell chondrogenesis and cartilage regeneration. Scanning electron microscopy (SEM) analysis showed the drug delivery spheres homogeneously distribution in the fibrous scaffold. Furthermore, CAP treatment renders the scaffold’s surface more hydrophilic and results in more specific vitronectin adsorption as illustrated by contact angle and ELISA testing. Our results showed that the CAP treated scaffold can greatly improve growth and chondrogenic differentiation (such as increased glycosaminoglycan (GAG) synthesis) of human bone marrow-derived mesenchymal stem cells (MSCs).
Multidrug-resistant bacteria are major causes of nosocomial infections and are associated with considerable morbidity, mortality, and healthcare costs. Preventive strategies have therefore become increasingly important. Mathematical modeling has been widely used to understand the transmission dynamics of nosocomial infections and the quantitative effects of infection control measures. This review will explore the principles of mathematical modeling used in nosocomial infections and discuss the effectiveness of infection control measures investigated using mathematical modeling.
Infect Control Hosp Epidemiol 2014;35(12):1521–1530
A radio-frequency magnetron sputtering technique and subsequent rapid thermal annealing (RTA) at 600, 700, 800, and 900 °C were implemented to grow high-quality Ga-doped MgxZn1-xO (GMZO) epi-layers. The GMZO films were deposited using a radio-frequency magnetron sputtering system and a 4 inch ZnO/MgO/Ga2O3 (75/20/5 wt %) target. The Hall results, X-ray diffraction (XRD), and transmittance were determined and are reported in this paper. The Hall results indicated that the increase in mobility was likely caused by the improved crystallization in the GMZO films after thermal annealing. The XRD results revealed that MgxZn1-xO (111) and MgO2 (200) peaks were obtained in the GMZO films. The absorption edges of the as-grown and annealed GMZO films shifted toward the short wavelength of 373 nm at a transmittance of 90%. According to these results, GMZO films are feasible for forming transparent contact layers for near-ultraviolet light-emitting diodes.