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Plasmodium vivax serological exposure markers (SEMs) have emerged as promising tools for the actionable surveillance and implementation of targeted interventions to accelerate malaria elimination. To determine the dynamic profiles of SEMs in current and past P. vivax infections, we screened and selected 11 P. vivax proteins from 210 putative proteins using protein arrays, with a set of serum samples obtained from patients with acute P. vivax and documented past P. vivax infections. Then we used a murine protein immune model to initially investigate the humoral and memory B cell response involved in the generation of long-lived antibodies. We show that of the 11 proteins, especially C-terminal 42-kDa region of P. vivax merozoite surface protein 1 (PvMSP1-42) induced longer-lasting long-lived antibodies, as these antibodies were detected in individuals infected with P. vivax in the 1960-1970s who were not re-infected until 2012. In addition, we provide a potential mechanism for the maintenance of long-lived antibodies after the induction of PvMSP1-42. The results indicate that PvMSP1-42 induces more CD73+CD80+ memory B cells (MBCs) compared to P. vivax GPI-anchored micronemal antigen (PvGAMA), allowing IgG anti-PvMSP1-42 antibodies to be maintained for a long time. Author summary: P. vivax serological exposure markers (SEMs) that reflect exposure to blood-stage P. vivax parasites, could play an important role in assessing progress towards malaria elimination. Serological surveillance can be a useful tool for identifying areas of high transmission intensity or hidden asymptomatic reservoirs, especially as malaria transmission declines. These immune responses can persist long after the clearance of blood-stage infection, making antibodies valuable markers for both past exposure and current infection status. Furthermore, gaining a better understanding of the host immune response to malaria, particularly regarding the induction and maintenance of high levels of circulating antibodies, is crucial for effective serological surveillance efforts. Using serum obtained in 2007 or 2012 from patients with acute P. vivax infection, 5-year, 12-year and 30-year recovery of P. vivax-infected patients we provide evidence that PvMSP1-42 induces long-lived anti-PvMSP1-42 antibodies. Then we used a murine protein immune model, show that more CD73+CD80+ memory B cells, allowing IgG anti-PvMSP1-42 antibodies to be maintained for a long time (Fig 1). The results of this study represent an important step forward in our understanding of the host immune response to P. vivax blood stages, including the induction and maintenance of high levels of circulating antibodies. These findings may have important implications for the development of effective serological surveillance tools. [ABSTRACT FROM AUTHOR]

With the growth of the global economy, changes in climate and ecological environments, and increased mobility of humans and animals, the transmission risk of vector-borne tropical diseases continues to rise. To address this challenge, strengthening surveillance of vector-borne tropical diseases is urgent. This consensus brought together 29 renowned experts in related professional fields from 26 institutions in China, who, through analyzing the epidemic trend and hazard situation of vector-borne tropical diseases and summarizing the working experiences of experts, have firstly reached following consensus: the burden of vector-borne tropical diseases is heavy with great threats to human health; China has achieved remarkable results in prevention and control of vector-borne tropical diseases, but still needs to strengthen the surveillance and response actively. Secondly, a unanimous consensus has been reached on the aspects of surveillance definition, objectives, contents, and methods of vector-borne tropical diseases. Thirdly, detail requirements have been agreed including: strengthening the concept of early surveillance and forecast, standarding the function, evaluation steps, and construction requirements of surveillance system for vector-borne tropical diseases. Fourthly, key tasks were put forward that need to be investigated and strengthened in the future. This expert consensus provides a standardized reference for the construction of the surveillance pathway and surveillance system for vector-borne tropical diseases in China. [ABSTRACT FROM AUTHOR]

BACKGROUND Lignin is an important component of marine organic carbon. It is also an important biomarker for extracting information on the evolution of the land and marine environment and tracking the source of organic marine matter. However, the existing analytical techniques are difficult to determine lignin directly. So, the content of phenolic compounds in the decomposition products of lignin in marine sediments were generally determined to indicate the content of lignin and the source of organic matter. The content of phenolic compounds in the decomposition products of lignin in marine sediments is often used to reflect the content of lignin. In addition, by calculating the diagnostic ratio of individual phenolic compounds, it also provides important information about the classification, source, and diagenesis of terrestrial organic matter in marine sediments. However, phenolic compounds in the decomposition products of lignin have the characteristics of strong polarity and low volatility, so they cannot be directly detected by gas chromatography and need to be derivatized first, which makes the sample processing complicated and often results in incomplete derivatization. Therefore, it is of great significance to develop a simple and reliable method for determination of phenolic compounds of the lignin decomposition products in marine sediments to explore the source of organic matter and understand the environmental evolution process. OBJECTIVES To establish a simple and reliable method for the determination of phenolic compounds of lignin decomposition products in marine sediments using solid phase extraction (SPE) combined with ultra-high performance liquid chromatography-high resolution mass spectrometry, and to trace the content level and source of lignin in the sediments of Laizhou Bay in China. METHODS Marine sediment samples were first decomposed with oxidative-alkaline CuO and extracted by solid phase extraction. Briefly, the oxidation was carried out in a polytetrafluoroethylene digestion tank. 1.00g of sediment sample, 500mg of copper oxide, and 100mg of ammonium ferrous sulfate were accurately weighed and placed in the tank. The components were thoroughly mixed with the sample and then the digestion tank was transferred to a glove box filled with nitrogen. 8.0mL of aqueous sodium hydroxide solution with a concentration of 8.0% (bubbled with N2 to remove dissolved oxygen) was added to the tank. The digestion tank was covered tightly and transferred to an oven heating to 150℃ for reaction, which was terminated after 3h. After the digestion tank cooled to room temperature, it was carefully unscrewed, and an internal standard (ethyl vanillin) solution was added. Subsequently, the hydrolysate was transferred to a centrifuge tube, spun at 8000r/min for 10min, and the supernatant and reaction residue was separated. 2.0mL of 1.0% sodium hydroxide solution was added to rinse the residue, and centrifuged at 8000r/min for 10min. Combining the centrifuged supernatant obtained twice, the solution was acidified to pH=1 with hydrochloric acid. After the solution was left to stand for 30 minutes, solid phase extraction was performed. The SPE procedure was as follows: A hydrophilic-lipophilic balance (HLB) SPE cartridge (200mg, 6mL) was conditioned with 5mL of methanol and 5mL of ultrapure water. Sample solution was passed through the cartridge in a flow rate 1.0mL/min, and then the cartridges were rinsed with 10mL water, and dried under vacuum for about 3min. Phenolic compounds were eluted with 10mL ethyl acetate, and were evaporated by a rotary evaporator, reconstituted with sample solvent. Then, ultra-high performance liquid chromatography using ZORBAX Eclipse XDB-C18 column with packing particle size of 1.8μm was used to directly separate all target compounds at 28℃, with gradient elution. The mobile phase was composed of ultrapure water with 0.1% formic acid (V/V) and acetonitrile/methanol (9:1, V/V) , and the flow rate was set to 0.25mL/min. Electrospray ionization (in positive) time of flight mass spectrometry was applied to detect target compounds in full scan mode, and quantification was performed using an internal standard determination. RESULTS Firstly, chromatographic conditions and solid phase extraction conditions were systematically optimized. Ultra-high performance liquid chromatography was used for the chromatographic separation of phenolic compounds from lignin decomposition products in marine sediments. The separation effects of three mobile phase systems, namely, water-acetonitrile, water- methanol, and water-methanol-acetonitrile, were compared. When using a water-methanol -acetonitrile ternary mobile phase system, the resolution of various phenolic compounds was superior to the commonly used water-acetonitrile or water-methanol binary mobile phase systems in the literature. In addition, the effects of mobile phase acidity (trifluoroacetic acid, formic acid, and acetic acid were added into the mobile phase) on the separation of various phenolic compounds were investigated. The results showed that adding a certain concentration of all three acids to the mobile phase provided better separation results. Considering the compatibility with mass spectrometry, it was finally determined that adding 0.1% formic acid into the mobile phase achieved good peak patterns and resolution. In order to determine the ionization mode suitable for the analysis of phenolic compounds from lignin decomposition products in marine sediment, electrospray ionization (ESI) mass spectrometry was performed on each target phenolic compound in ESI+ and ESI− mode, respectively. Under ESI+ mode, various target phenolic compounds were less affected by interfering substances in the sample matrix, and the MS response value for most of the phenolic compounds was higher than that found in ESI− mode. Hence, ESI-TOF/MS in positive mode was selected to determine phenolic compounds of lignin decomposition products in marine sediment. Subsequently, the fragmentation voltage was optimized to obtain the highest sensitivity for all target phenolic compounds, which was the main mass spectrometric condition that affected the quantification accuracy and sensitivity. The effect of fragmentation voltage on the MS response signal of each target phenolic compound was investigated in the range of 80V to 200V. Overall, considering the detection sensitivity of the [M+H]+ ion peak of each target compound, 130V was selected as the optimal fragmentation voltage to determine phenolic compounds of lignin decomposition products in marine sediment. The effect of pH (1.0-2.5) of the loading solution for solid phase extraction on the extraction efficiency of various target phenolic compounds was systematically investigated, to ensure that the phenolic compounds of lignin decomposition products in marine sediments have a good recovery rate during the SPE process. When the pH of the loading solution was 1.0 and 1.5, the recovery rate of various phenolic compounds by using HLB solid phase extraction column was significantly higher than that of the loading solution adjusted pH to 2.0 and 2.5. When the pH of the sample solution was 1.0 and 1.5, although the recoveries of syringaldehyde and acetovanillone were relatively similar, the recoveries of other phenolic compounds were the highest at a pH of 1.0. Considering the recovery rate of all the target phenolic compounds and applicability of the method, the pH of the sample solution was confirmed to adjust to 1.0. In this study, HLB SPE column with 200mg of packing material was used to enrich phenolic compounds in sample extraction solution. Generally, 5-10mL of eluting solvent can ensure the full elution of all target phenolic compounds adsorbed on the SPE column. Therefore, based on the results of literature research, ethyl acetate was finally selected as the eluting solvent, with a dosage of 10mL. Under the optimum experimental conditions, the 11 main decomposition phenol compounds of lignin in marine sediments were well separated within 20 minutes. The proposed method had good precision (RSD was less than 9.0%), the correlation coefficient (R2) was not less than 0.9989 in the linear range, and the recovery rate of all spiked phenol compounds in blank marine sediment was in the range of 86.8%-93.2%, thereby indicating that the developed method would be suitable to determine the target decomposition phenol compounds of lignin in marine sediment. Subsequently, the method was used to determine the phenolic compounds of lignin decomposition products in the surface sediments of Laizhou Bay. The detection rate of 11 target phenolic compounds in 12 surface sediment samples was 100%, and the concentration of Σ8 in 12 surface sediment samples ranged from 0.001mg/10gds to 0.019mg/10gds. The value of C/V was between 0.18 and 0.81, with an average of 0.38; the value of S/V was between 0.18 and 0.45, with an average of 0.26; PON/P value was between 0.01 and 0.07, with an average of 0.03; P/(V+S) value was between 0.55 and 3.77, with an average of 1.44; (Ad/Al)v value was between 0.12 and 1.07, with an average of 0.48; the value of (Ad/Al)s was between 0.15 and 1.26, with an average of 1.02. CONCLUSIONS The above diagnostic ratios indicate that the lignin in the surface sediments of Laizhou Bay originate mainly from the herbaceous tissue of angiosperms, while the proportion of organic matter in vascular plants is relatively low. The degradation degree of terrestrial organic matter in most sampling stations is medium or high, but there is still a small amount of fresh plant debris. The proposed method has the advantages of high efficiency, simple for sample pretreatment, and is a powerful technique for the determination of main decomposition product phenolic compounds of lignin in marine sediments.

Iran is an important political power and strategic hub in the Middle East, connecting Central Asia and West Asia, acting as a significant route from Asia to North Africa and Europe; it is an intersection of the "Silk Road Economic Belt" and the "21st Century Maritime Silk Road". Coupled with the enrichment of petroleum resources and the control of global oil security, Iran's geostrategic position is very important. This study constructs a geo-potential mathematical model and index system from a spatial perspective, including the geo-weight evaluation index system, weight distribution, interdependence index, and geo-distance measurements while innovatively incorporating the element of geostrategic investment willingness. Based on these factors, this study conducts a quantitative, comparative analysis of the geo-potential of China, the USA, and Russia in Iran after September 11st, 2001, from two dimensions—"strong-weak" and "positive-negative." Subsequently, the driving factors and mechanisms of geo-potential are obtained through mathematical model construction and empirical research. Finally, by placing Iran on regional and global scales and thoroughly considering both international and regional geopolitical patterns around foreign policy and strategy, we analyze geopolitical relations between China, the USA, Russia, and Iran: diplomatic, economic, and cultural factors considered from a geo-potential perspective. We hope that this study will enrich research on Iran studies and geopolitical studies, through its understanding of the power interaction mechanism and geopolitical relations between global powers and Iran, while providing a research basis to promote the high-quality development of the Belt and Road Initiative. The following conclusions were drawn: (1) The USA's geo-potential in Iran fluctuates frequently in the negative high range, and Russia's geo-potential fluctuates slightly in the positive median range. Fluctuations between these two countries thus show a "strong - strong" interaction. The change of China's geo-potential is relatively separate from that of the USA and Russia, showing an "S" shaped curve trending upward, thus gradually narrowing the gap with Russia. Russia and China have a positive influence on Iran (attraction), while the USA has a negative influence on Iran (repulsion), which is much stronger than the attraction from Russia and China. (2) Geo-diplomacy is the decisive factor guiding the trend of geo-economy and geo-culture. Geo-economy is the direct driving force of the evolution of geo-potential. Geo-culture acts as a collaborative factor; geo-economy and geo-culture both have a potential influence on geo-diplomacy. (3) Based on amicable geo-cultural relations, the strengthening of China's comprehensive national strength and the deepening of bilateral economic interdependence constantly enhances the intensity of geopolitical relations between China and Iran. The geopolitical relationship between the USA and Iran is occasionally eased but is generally poor. Volatility is largely due to changes in foreign policy triggered by the change of governments, which is the dual response of the domestic political system and the international political environment. The close geopolitical relationship between Russia and Iran is owing to the geographical proximity and the need for a geo-strategy. There is a stable but complex geopolitical relationship network between these two countries, composed of economic, political, and security factors.

Novel yellow to blackish green Ni-doped aluminium titanate (Al2TiO5) ceramic pigments were synthesized by solid-state reaction method at 1400 °C. Effects of nickel doping content on phase composition, microstructure, optical properties and stability were studied. The results show that the higher content of Al2TiO5 phase and the reduction of the lattice distortion of aluminium titanate could be attributed to the entry of nickel ions into aluminium titanate lattice resulting in the formation of solid solution. Ni-doped aluminium titanate ceramic pigments show exceptional glaze colouring and are expected to be promising high-temperature pigments.

The mainshock location of the Badong Ms5.1 earthquake is determined using four location methods: the simplex method, HYP2000, hyposat, and locSAT; the 350 aftershocks over 3 months are relocated using the double difference location method. The results indicate that aftershocks are distributed as bands along the NEE direction and that the aftershocks 1 month after the mainshock, which are mainly distributed in the west of the mainshock and near the Gaoqiao fault, are shallow earthquakes within 5 km; the depth of each aftershock after one month is deeper, and two distinct fault planes, for which the geological occurrence is similar to the Gaoqiao and Zhoujiashan-Niukou fault, are shaped. The frequency-spectrum analysis of the recorded waveform in 12 seismic events indicates that the corner frequency of the mainshock is significantly lower than that of its aftershock and is also lower than a tectonic earthquake of the same magnitude. We considered that this result is related to the constraint of the parameter calibration relationship in the focal spectrum and the lithology change due to water erosion. Combined with the focal mechanism and geological tectonic setting, we conclude that the occurrence of the earthquake is related to the activity of the Daping and Gaoqiao fault and is a reservoir-induced tectonic seismicity.

The focal mechanism solutions of the M5. 1 Badong earthquake and subsequent 34 aftershocks at ML 2. 0 or more were calculated using the P-wave first motion method; the main earthquake was normal fault dip slip type, and the slip types of the seismogenic rupture surfaces of the subsequent aftershocks primarily include normal dip slip (14 times), reverse dip slip (9 times), normal strike slip (9 times) and reverse strike slip (2 times). The M5. 1 Badong earthquake activities may be related to the stress adjustment caused by the rise of the groundwater level and the decrease of the frictional resistance betvveen structural planes of rock formations due to the effect of reservoir water penetration, and related to the joint activities of the NE-strike Gaoqiao fault and the near EW-strike Daping fault.

In order to provide technical guidance for the construction of rock embankment with a thickness greater than 60 cm, thehigh-power roller with self-weight of 32tand supporting construction machinery have been used to carryoutfield experimentson vibration compaction of large thickness rock embankment, and several indexes of compaction quality have been comparedand evaluated, so the quality detection method and evaluation criteria of large thickness vibration compaction of rockembankment have beenobtained.The results showsthatforthe vibration compaction of the hard rock embankment with large thickness, the effective rolling thickness of the high-power vibratory roller with 32tweight is 90cm.It is suggested that the comprehensive parameters such as loosenesscoefficient, settlement difference and construction technology should be adopted toevaluatingcompaction quality. The standard of compacting quality is: the loosenesscoefficient should be greater than 1.16, the average settlement difference of the last rolling should not exceed 5mm, and the high-power roller should roll more than 6 times.

What Is Already Known About This Topic?: Sierra Leone, with a gross domestic product (GDP) per capita below $300 and significant poverty, ranks among the world's least developed countries (LDCs). Despite its modest population of 8.6 million, the nation reports approximately 2.6 million malaria cases annually. Previously, there has been no reporting on the malaria genome data from this country., What Is Added by This Report?: In this study, we present the first reported whole-genome sequence analysis of 19 high parasite-density Plasmodium falciparum isolates from Sierra Leone, providing insights into the genomic epidemiology of this high-prevalence area. We found a high degree of relatedness among infections and substantial genetic diversity, consistent with the gradual reduction in overall case numbers. Moreover, our whole-genome analysis revealed that, beyond drug-resistance genes, gene families related to blood cell invasion, immune evasion, and others are undergoing directional selection. This suggests that the population in Sierra Leone has developed a relatively strong acquired immunity., What Are the Implications for Public Health Practice?: The genomic data not only facilitate the creation of single nucleotide polymorphism barcodes for case tracking but also enable the analysis of evolving transmission dynamics and selection pressures. Additionally, the samples from Sierra Leone exhibited higher selective pressures on resistance genes compared to those from Asia, a trend not commonly observed in other African samples. This suggests that less stringent healthcare systems and inconsistent treatment strategies can subject parasites to increased drug pressure, thereby accelerating the development of resistant strains., Competing Interests: No conflicts of interest., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2024.)

Babesiosis caused by Babesia species imposes an increasing threat to public-health and so far, there is no effective vaccine to prevent Babesia infections. Babesia surface antigen may participate in the invasion of erythrocytes. In our previous study, a surface antigen of B. microti merozoites, named as Bm SP44 was identified as a dominant reactive antigen by protein microarray screening. To evaluate its potential applications in diagnosis and prevention of Babesiosis, the open reading frame encoding Bm SP44 was cloned and the recombinant protein was expressed. In consistent with the protein microarray result, recombinant Bm SP44 (r Bm SP44) can be recognized by sera from B. microti infected mice. Immunofluorescence assays (IFA) confirmed that Bm SP44 is a secreted protein and localized principally in the cytoplasm of the parasites. The parasitemia and Babesia gene copies were lower in mice administered r Bm SP44 antisera compared with normal controls. Active immunization with r Bm SP44 also afforded protection against B. microti infection. The concentrations of hemoglobin in r Bm SP44 immunization group were higher than those in the control group. Importantly, vaccination of mice with r Bm SP44 resulted in a Th1/Th2 mixed immune response with significantly elevated IL-10 and IFN-γ levels during the early stage of infection. Taken together, our results indicated that r Bm SP44 can induce a protective immune response against Babesia infection. Thus, Bm SP44 can be used as both a diagnosis marker and a vaccine candidate., (Copyright © 2020 Wang, Wang, Huang, Xu, Chen, Dai and Zhou.)