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Electrocatalytic hydrogen peroxide (H2O2) production via two-electron oxygen reduction reaction (2e--ORR) features energy-saving and eco-friendly characteristics, making it a promising alternative to the anthraquinone oxidation process. However, the common existence of numerous 2e--ORR-inactive sites/species on electrocatalysts tends to catalyze side reactions, especially under low potentials, which compromises energy efficiency and limits H2O2 yield. Addressing this, a high surface density of mono-species pyrrolic nitrogen configurations is formed over a polypyrrole@carbon nanotube composite. Thermodynamic and kinetic calculation and experimental investigation collaboratively confirm that these densely distributed and highly selective active sites effectively promote high-rate 2e--ORR electrocatalysis and inhibit side reactions over a wide potential range. Consequently, an ultra-high and stable H2O2 yield of up to 67.9/51.2 mol g-1 h-1 has been achieved on this material at a current density of 200/120 mA cm-1, corresponding Faradaic efficiency of 72.8/91.5%. A maximum H2O2 concentration of 13.47 g L-1 can be accumulated at a current density of 80 mA cm-1 with satisfactory stability. The strategy of surface active site densification thus provides a promising and universal avenue toward designing highly active and efficient electrocatalysts for 2e--ORR as well as a series of other similar electrochemical processes.

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To investigate the clinical characteristics, early blood biochemical indicators, and prognostic status of children with bronchopneumonia. We conducted a retrospective analysis of data from 500 children diagnosed with bronchopneumonia at our hospital from June 2019 to December 2022. Based on the severity of the disease, patients were assigned to the severe group (n = 180) or mild group (n = 320), and an additional 150 healthy children were chosen as the control group. Blood indicators [aspartate aminotransferase (AST), plasma carbon dioxide combining power (CO2CP), serum potassium (K+), serum sodium (Na+)], inflammatory markers [interleukin-17 (IL-17), interleukin-10 (IL-10), C-reactive protein (CRP), procalcitonin (PCT)], and cardiac enzyme profiles [lactate dehydrogenase (LDH), creatine kinase (CK), alpha-hydroxybutyrate dehydrogenase (α-HBDH), creatine kinase isoenzyme (CK-MB)] were compared among the 3 groups. The severe group showed more signs such as diarrhea, pleural effusion, and respiratory distress than the mild group. AST levels in the severe group were significantly higher than those in the mild group and control group, while CO2CP, K+, and Na+ were lower than those in the mild group and control group. AST levels in the mild group were significantly higher than those in the control group, while CO2CP and Na + were significantly higher than those in the control group (P < .05). IL-10, IL-17, PCT, and CRP levels in the severe group were higher than those in the mild group and control group, while those in the mild group were higher than those in the control group (P < .05). CK, CK-MB, LDH, and α-HBDH levels in the severe group were significantly higher than those in the mild group and control group. CK, CK-MB, LDH, and α-HBDH levels in the mild group were higher than those in the control group (P < .05). The severe group had a longer duration of fever, disappearance of symptoms, and cough relief time than the mild group (P < .05). Children with bronchopneumonia exhibit increased cardiac enzyme (CK, CK-MB, LDH, and α-HBDH) activity, and PCT and CRP expression levels increase with disease severity. Timely detection of relevant blood biochemical indicators and early implementation of prevention and treatment measures can improve the cure rate and reduce mortality in children with bronchopneumonia.

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Remittances received by households from international migrants are of interest in an increasing number of microeconomic analyses. Making use of novel data, we measure misreporting of remittances sent by migrants in the United Arab Emirates (UAE) to remittance recipients in the Philippines. We obtained administrative transaction data from a sample of Filipino migrants who were clients of a popular money transfer operator (MTO). We then surveyed these migrants as well as their primary remittance recipients about the same remittance flows. Migrant-reported remittances are only 6% lower than MTO administrative records, and we cannot reject their equality. A custom smartphone app designed to facilitate migrant remittance reporting does not help raise reporting accuracy. Recipient-reported remittances are 23% lower than migrant reports on average. Recipients under-report even more when they receive remittances less frequently and when remittances make up a lower share of household income.

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BACKGROUND AND PURPOSE: Prioritizing a drug therapy problem (DTP) during an experiential placement is challenging for some pharmacy students, suggesting a gap in pre-placement preparedness and the need to modify existing resources. A modified DTP prioritizing framework is proposed to enhance clinical reasoning and increase students' confidence in performing this important step in the pharmaceutical care process. EDUCATIONAL ACTIVITY AND SETTING: Students' baseline DTP prioritizing capability was assessed in an informal focus group consisting of pharmacy students and experienced hospital pharmacy preceptors. Participants ranked the urgency for addressing 47 common medical conditions and selected a time frame to resolve the DTP. Participants also provided feedback on a proposed DTP prioritizing framework. A modified, student-focused DTP prioritizing framework, incorporating elements of curricular knowledge, principal elements of urgency, and time frame for taking action to resolve the identified DTP is described. FINDINGS: Students' DTP urgency rankings were heterogeneous and showed greater deviation from the anticipated ranking (R = 0.61) compared to the pharmacist cohort (R = 0.807), reinforcing our view of the need for a modified DTP prioritizing framework for students. In qualitative terms, students felt the framework's focus on curricular knowledge would contribute to the development of expertise. Preceptors felt the framework reflected their usual practice and would help guide discussions with students. SUMMARY: The modified DTP prioritizing framework, described in this article, may be utilized both to enhance student success and preceptor development in the experiential setting.

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Interventions to promote learning are often categorized into supply- and demand-side approaches. In a randomized experiment to promote learning about COVID-19 among Mozambican adults, we study the interaction between a supply and a demand intervention, respectively: teaching via targeted feedback, and providing financial incentives to learners. In theory, teaching and learner-incentives may be substitutes (crowding out one another) or complements (enhancing one another). Experts surveyed in advance predicted a high degree of substitutability between the two treatments. In contrast, we find substantially more complementarity than experts predicted. Combining teaching and incentive treatments raises COVID-19 knowledge test scores by 0.5 standard deviations, though the standalone teaching treatment is the most cost-effective. The complementarity between teaching and incentives persists in the longer run, over nine months post-treatment.

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Does variation in how religious festivals are celebrated have economic consequences? We study the economic impacts of the timing of Catholic patron saint day festivals in Mexico. For causal identification, we exploit cross-locality variation in festival dates and in the timing of agricultural seasons. We estimate the impact of "agriculturally-coinciding" festivals (those coinciding with peak planting or harvest months) on long-run economic development of localities. Agriculturally-coinciding festivals lead to lower household income and worse development outcomes overall. These negative effects are likely due to lower agricultural productivity, which inhibits structural transformation out of agriculture. Agriculturally-coinciding festivals may nonetheless persist because they also lead to higher religiosity and social capital.

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How readily do potential migrants respond to increased returns to migration? Even if origin areas become less attractive vis-à-vis migration destinations, fixed costs can prevent increased migration. We examine migration responses to hurricanes, which reduce the attractiveness of origin locations. Restricted-access U.S. Census data allows precise migration measures and analysis of more migrant-origin countries. Hurricanes increase U.S. immigration, with the effect increasing in the size of prior migrant stocks. Large migrant networks reduce fixed costs by facilitating legal immigration from hurricane-affected source countries. Hurricane-induced immigration can be fully accounted for by new legal permanent residents ("green card" holders).

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We implement a randomized experiment offering Salvadoran migrants matching funds for educational remittances, which are channeled directly to a beneficiary student in El Salvador chosen by the migrant. The matches lead to increased educational expenditures, higher private school attendance, and lower labor supply of youths in El Salvador households connected to migrant study participants. We find substantial "crowd-in" of educational investments: for each $1 received by beneficiaries, educational expenditures increase by $3.72. We find no shifting of expenditures away from other students, and no effect on remittances.

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The high-volume resistivity and surface resistance of poly(ether ether ketone)/multiwalled carbon nanotubes (PEEK/MWCNT) composites restrict their use in an electronic field. To decrease the volume resistivity and surface resistance, we metalized the composites by electroless plating. The composites and metal coatings were characterized by SEM, XPS, AFM, EDX, and XRD spectroscopy. The swelling ratio of the composites, volume resistivity of two-side-coated composites, sheet resistance of plated composites, and adhesion between the coating and PEEK/MWCNT were tested. The results are as follows. A high roughness and a small swelling ratio were obtained by swelling in 18 mol/L H2SO4 for 3 min. Most of the MWCNT on the surface were still wrapped with PEEK after swelling. To expose the MWCNT, an environmentally friendly and effective etchant (MnO2-NaH2PO4-H2SO4) was used. After etching, not only were high roughness and partially exposed MWCNT obtained but also the percentage of hydrophilic groups on the surface was increased. A dense cauliflower-like Ni-P coating was produced, and the exposed MWCNT were embedded in the metal coating after electroless plating for 20 min. The coating exhibited an amorphous structure with a phosphorus content of 11.21 wt %. The volume resistivity of two-side-coated PEEK/MWCNT dropped sharply to 38 Ω·m after electroless plating for 5 min. The sheet resistance decreased with increasing the electroless-plating time, and it dropped to 0.88 Ω/square after electroless plating for 40 min. The adhesion of the coating reached the highest 5 B scale (ASTM D3359) and could even undergo the test 20 times.

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Poly (propylene fumarate)/(Calcium sulfate/ß-tricalcium phosphate) (PPF/(CaSO(4)/ß-TCP)) is a kind of biodegradable composite designed for bone tissue engineering. The in vitro degradation behavior of this composite has been investigated in our previous study. The aim of this study was to investigate the effects of PPF molecular weight and CaSO(4)/ß-TCP molar ratio on the in vivo degradation of PPF/(CaSO(4)/ß-TCP) composite and the bone tissue response to PPF/(CaSO(4)/ß-TCP). Total 36 PPF/(CaSO(4)/ß-TCP) composite samples were implanted into 15.0 mm segmental defects in tibiae of 18 Japanese rabbits, harvested at 2, 4 and 8 weeks after the operation, and analyzed using radiographic and histological analysis to assess the in vivo degradation of the composites as well as tissue response to the implants. The in vivo degradation results show that all the samples maintained their original shape. Tissues penetrated into the pores which formed by the degradation of CaSO(4)/ß-TCP spheres near the surface of the composites. The rate of in vivo degradation and pore forming increased with a decrease in PPF molecular weight and an increase in CaSO(4)/ß-TCP molar ratio. No inflammatory reaction was observed after implantation, and the composites are capable of in situ pore forming. In particular, the pore forming rate can be adjusted by varying the composition of the composites. These results may indicate that PPF/(CaSO(4)/ß-TCP) is a promising osteogenic scaffold for its controllable degradation rate and excellent biocompatibility.

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This study aimed to prepare a poly(propylene fumarate)/(calcium sulphate/beta-tricalcium phosphate) (PPF/(CaSO(4)/beta-TCP)) composite. We first examined the effects of varying the molecular weight of PPF and the N-vinyl pyrrolidinone (NVP) to PPF ratio on the maximum cross-linking temperature and the composite compressive strength and modulus. Then the in vitro biodegradation behaviour of PPF/(CaSO(4)/beta-TCP) composites was investigated. The effects of varying the molecular weight of PPF, the NVP/PPF ratio and the CaSO(4)/beta-TCP molar ratio on the weight loss and the composite compressive strength and modulus were examined. The cross-linking temperature, which increased with increasing molecular weight of PPF and NVP/PPF ratio, ranged from 41 to 43 degrees C for all formulations. The mechanical properties were increased by a decrease in the NVP/PPF ratio. For all formulations, the compressive strength values fell between 12 and 62 MPa, while the compressive modulus values fell between 290 and 1149 MPa. The weight loss decreased either with increasing molecular weight of PPF or with decreasing NVP/PPF ratio and CaSO(4)/beta-TCP molar ratio during degradation. The compressive strength and modulus increased with decreasing NVP/PPF ratio or decreasing CaSO(4)/beta-TCP ratio. The greatest weight loss over 6 weeks was 14.72%. For all formulations, the compressive modulus values fell between 57 and 712 MPa and the compressive strength fell between 0.5 and 21 MPa throughout 6 weeks degradation. Scanning electron microscopy and X-ray diffraction analysis of the PPF/(CaSO(4)/beta-TCP) composites demonstrated that hydroxyapatite was deposited on the surface of CaSO(4)/beta-TCP granules during degradation.

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Poly (propylene fumarate) is an unsaturated linear polyester, which degrades, in the presence of water, into propylene glycol and fumaric acid, and the degradation products can be cleared from the human body by normal metabolic processes. In this paper, different methods of the synthesis of PPF are listed, the crosslinking characteristics of polymerizing composite as well as the mechanical properties of cross-linked composite are discussed, and the potentialities of PPF composite used as particularly degradable polymeric cement for orthopedic application are reviewed.

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