Microbial carbon use efficiency promotes global soil carbon storage.

Soils store more carbon than other terrestrial ecosystems1,2. How soil organic carbon (SOC) forms and persists remains uncertain1,3, which makes it challenging to understand how it will respond to climatic change3,4. It has been suggested that soil microorganisms play an important role in SOC formation, preservation and loss5-7. Although microorganisms affect the accumulation and loss of soil organic matter through many pathways4,6,8-11, microbial carbon use efficiency (CUE) is an integrative metric that can capture the balance of these processes12,13. Although CUE has the potential to act as a predictor of variation in SOC storage, the role of CUE in SOC persistence remains unresolved7,14,15. Here we examine the relationship between CUE and the preservation of SOC, and interactions with climate, vegetation and edaphic properties, using a combination of global-scale datasets, a microbial-process explicit model, data assimilation, deep learning and meta-analysis. We find that CUE is at least four times as important as other evaluated factors, such as carbon input, decomposition or vertical transport, in determining SOC storage and its spatial variation across the globe. In addition, CUE shows a positive correlation with SOC content. Our findings point to microbial CUE as a major determinant of global SOC storage. Understanding the microbial processes underlying CUE and their environmental dependence may help the prediction of SOC feedback to a changing climate.

Development of genus-specific universal primers for the detection of flaviviruses.

BACKGROUND: Flaviviruses are representative arboviruses carried by arthropods and/or vertebrates; these viruses can pose a public health concern in many countries. By contrast, it is known that a novel virus group called insect-specific flaviviruses (ISFs) also infects arthropods, although no such virus has yet been isolated from vertebrates. The characteristics of ISFs, which affect replication of human-pathogenic flaviviruses within co-infected mosquito cells or mosquitoes without affecting the mosquitoes themselves, mean that we should pay attention to both ISFs and human-pathogenic flaviviruses, despite the fact that ISFs appear not to be directly hazardous to human health. To assess the risk of diseases caused by flaviviruses, and to better understand their ecology, it is necessary to know the extent to which flaviviruses are harbored by arthropods. METHODS: We developed a novel universal primer for use in a PCR-based system to detect a broad range of flaviviruses. We then evaluated its performance. The utility of the novel primer pair was evaluated in a PCR assay using artificially synthesized oligonucleotides derived from a template viral genome sequence. The utility of the primer pair was also examined by reverse transcription PCR (RT-PCR) using cDNA templates prepared from virus-infected cells or crude supernatants prepared from virus-containing mosquito homogenates. RESULTS: The novel primer pair amplified the flavivirus NS5 sequence (artificially synthesized) in all samples tested (six species of flavivirus that can cause infectious diseases in humans, and flaviviruses harbored by insects). In addition, the novel primer pair detected viral genomes in cDNA templates prepared from mosquito cells infected with live flavivirus under different infectious conditions. Finally, the viral genome was detected with high sensitivity in crude supernatants prepared from pooled mosquito homogenates. CONCLUSION: This PCR system based on a novel primer pair makes it possible to detect arthropod-borne flaviviruses worldwide (the primer pair even detected viruses belonging to different genetic subgroups). As such, an assay based on this primer pair may help to improve public health and safety, as well as increase our understanding of flavivirus ecology.

Courtship activity, copulation & insemination success in a mosquito vector fed a herbal aphrodisiac: Implications for sterile insect technology.

BACKGROUND & OBJECTIVES: In sterile insect technology (SIT), mating competitiveness is a pre-condition for the reduction of target pest populations and a crucial parameter for judging efficacy. Still, current SIT trials are being hindered by decreased effectiveness due to reduced sexual performance of released males. Here, we explored the possible role of a herbal aphrodisiac in boosting the mating activity of Aedes aegypti. METHODS: Males were fed one of two diets in this study: experimental extract of Eurycoma longifolia (MSAs) and sugar only (MSOs). Differences in life span, courtship latency, copulation activity and mating success were examined between the two groups. RESULTS: No deaths occurred among MSA and MSO males. Life span of MSOs was similar to that of MSAs. The courtship latency of MSAs was shorter than that of MSOs (P<0.01). MSAs had greater copulation success than MSOs (P<0.001). In all female treatments, MSAs mated more than MSOs, but the differences in rate were significant only in the highest female density (P<0.05). In MSAs, mating success varied significantly with female density (P<0.01), with the 20-female group (P<0.01) having the lowest rate. Single MSA had better mating success at the two lowest female densities. In MSOs, there were no significant differences in mating success rate between the different female densities. INTERPRETATION & CONCLUSIONS: Our results suggested that the herbal aphrodisiac, E. longifolia, stimulated the sexual activity of Ae. aegypti and may be useful for improving the mating competitiveness of sterile males, thus improving SIT programmes.

Co-Infection of Mosquitoes with Chikungunya and Dengue Viruses Reveals Modulation of the Replication of Both Viruses in Midguts and Salivary Glands of Aedes aegypti Mosquitoes.

Arthropod-borne virus (arbovirus) infections cause several emerging and resurgent infectious diseases in humans and animals. Chikungunya-affected areas often overlap with dengue-endemic areas. Concurrent dengue virus (DENV) and chikungunya virus (CHIKV) infections have been detected in travelers returning from regions of endemicity. CHIKV and DENV co-infected Aedes albopictus have also been collected in the vicinity of co-infected human cases, emphasizing the need to study co-infections in mosquitoes. We thus aimed to study the pathogen-pathogen interaction involved in these co-infections in DENV/CHIKV co-infected Aedes aegypti mosquitoes. In mono-infections, we detected CHIKV antigens as early as 4 days post-virus exposure in both the midgut (MG) and salivary gland (SG), whereas we detected DENV serotype 2 (DENV-2) antigens from day 5 post-virus exposure in MG and day 10 post-virus exposure in SG. Identical infection rates were observed for singly and co-infected mosquitoes, and facilitation of the replication of both viruses at various times post-viral exposure. We observed a higher replication for DENV-2 in SG of co-infected mosquitoes. We showed that mixed CHIKV and DENV infection facilitated viral replication in Ae. aegypti. The outcome of these mixed infections must be further studied to increase our understanding of pathogen-pathogen interactions in host cells.

Detection of chikungunya virus antigen by a novel rapid immunochromatographic test.

Chikungunya fever is a mosquito-borne disease of key public health importance in tropical and subtropical countries. Although severe joint pain is the most distinguishing feature of chikungunya fever, diagnosis remains difficult because the symptoms of chikungunya fever are shared by many pathogens, including dengue fever. The present study aimed to develop a new immunochromatographic diagnosis test for the detection of chikungunya virus antigen in serum. Mice were immunized with isolates from patients with Thai chikungunya fever, East/Central/South African genotype, to produce mouse monoclonal antibodies against chikungunya virus. Using these monoclonal antibodies, a new diagnostic test was developed and evaluated for the detection of chikungunya virus. The newly developed diagnostic test reacted with not only the East/Central/South African genotype but also with the Asian and West African genotypes of chikungunya virus. Testing of sera from patients suspected to have chikungunya fever in Thailand (n = 50), Laos (n = 54), Indonesia (n = 2), and Senegal (n = 6) revealed sensitivity, specificity, and real-time PCR (RT-PCR) agreement values of 89.4%, 94.4%, and 91.1%, respectively. In our study using serial samples, a new diagnostic test showed high agreement with the RT-PCR within the first 5 days after onset. A rapid diagnostic test was developed using mouse monoclonal antibodies that react with chikungunya virus envelope proteins. The diagnostic accuracy of our test is clinically acceptable for chikungunya fever in the acute phase.

Untangling the Effect of Carbonaceous Materials on the Photoelectrochemical Performance of BaTaO2N.

The water oxidation reaction is a rate-determining step in solar water splitting. The number of surviving photoexcited holes is one of the most influencing factors affecting the photoelectrochemical water oxidation efficiency of photocatalysts. The solar-to-hydrogen energy conversion efficiency of BaTaO2N is still far below the benchmark efficiency set for practical applications, notwithstanding its potential as a 600 nm-class photocatalyst in solar water splitting. To improve its efficiency in photoelectrochemical water splitting, this study offers a straightforward route to develop photocatalytic materials based on the combination of BaTaO2N and carbonaceous materials with different dimensions. The impact of diverse carbonaceous materials, such as fullerene, g-C3N4, graphene, carbon nanohorns, and carbon nanotubes, on the photoelectrochemical behavior of BaTaO2N has been examined. Notably, the use of graphene and g-C3N4 remarkably improves the photoelectrochemical performance of the composite photocatalysts through a higher photocurrent and acting as electron reservoirs. Consequently, a marked reduction in recombination rates, even at low overpotentials, leads to a higher accumulation of photoexcited holes, resulting in 2.6- and 1.7-fold increased BaTaO2N photocurrent densities using graphene and g-C3N4, respectively. The observed trends in the dark for the oxygen reduction reaction (ORR) potential align with the increase in the photocurrent density, revealing a good correlation between opposite phenomena. Importantly, the enhancement observed implies an underlying accumulation phenomenon. The verification of this concept lies in the evidence provided by oxygen reduction and is in line with photoredox flux matching during photocatalysis. This research underscores the intricate interplay between carbonaceous materials and oxynitride photocatalysts, offering a strategic approach to enhancing various photocatalytic capabilities.

Perovskite BaTaO2 N: From Materials Synthesis to Solar Water Splitting.

Barium tantalum oxynitride (BaTaO2 N), as a member of an emerging class of perovskite oxynitrides, is regarded as a promising inorganic material for solar water splitting because of its small band gap, visible light absorption, and suitable band edge potentials for overall water splitting in the absence of an external bias. However, BaTaO2 N still exhibits poor water-splitting performance that is susceptible to its synthetic history, surface states, recombination process, and instability. This review provides a comprehensive summary of previous progress, current advances, existing challenges, and future perspectives of BaTaO2 N for solar water splitting. A particular emphasis is given to highlighting the principles of photoelectrochemical (PEC) water splitting, classic and emerging photocatalysts for oxygen evolution reactions, and the crystal and electronic structures, dielectric, ferroelectric, and piezoelectric properties, synthesis routes, and thin-film fabrication of BaTaO2 N. Various strategies to achieve enhanced water-splitting performance of BaTaO2 N, such as reducing the surface and bulk defect density, engineering the crystal facets, tailoring the particle morphology, size, and porosity, cation doping, creating the solid solutions, forming the heterostructures and heterojunctions, designing the photoelectrochemical cells, and loading suitable cocatalysts are discussed. Also, the avenues for further investigation and the prospects of using BaTaO2 N in solar water splitting are presented.

Identification of Three Novel Genes in Phenuiviridae Detected from Aedes Mosquitoes in Hokkaido, Japan.

Mosquitoes are important arthropod vectors of arboviruses. The family Phenuiviridae includes several medically important arboviruses, such as the Rift Valley fever phlebovirus and Toscana phlebovirus. Recent comprehensive genetic analyses have identified many novel mosquito-specific viruses that are phylogenetically related to Phenuiviridae. We collected mosquitoes from Hokkaido in northern Japan, and conducted reverse transcription polymerase chain reactions (RT-PCRs) targeting the RNA-dependent RNA polymerase (RdRp) gene of Phenuiviridae. A total of 285 pools, comprising 3,082 mosquitoes from 2 genera and 8 species, were collected. Partial RdRp sequences were detected in 97 pools, which allowed us to classify the viruses into 3 clusters provisionally designated as Etutanne virus (ETTV) 1, 2, and 3. The virus most closely related to ETTVs is Narangue virus (family Phenuiviridae, genus Mobuvirus), which was detected in Mansonia mosquitoes; the nucleotide and amino acid sequences of the Narangue virus are 58.4-66.2% and 64.7-86.7% similar, respectively, to those of ETTVs. PCR and RT-PCR using DNA and RNase digestion methods showed that the ETTVs are RNA viruses that do not form non-retroviral integrated RNA virus sequences in the mosquito genome.

Identification of the Tembusu Virus in Mosquitoes in Northern Thailand.

Among emerging zoonotic pathogens, mosquito-borne viruses (MBVs) circulate between vertebrate animals and mosquitoes and represent a serious threat to humans via spillover from enzootic cycles to the human community. Active surveillance of MBVs in their vectors is therefore essential to better understand and prevent spillover and emergence, especially at the human-animal interface. In this study, we assessed the presence of MBVs using molecular and phylogenetic methods in mosquitoes collected along an ecological gradient ranging from rural urbanized areas to highland forest areas in northern Thailand. We have detected the presence of insect specific flaviviruses in our samples, and the presence of the emerging zoonotic Tembusu virus (TMUV). Reported for the first time in 1955 in Malaysia, TMUV remained for a long time in the shadow of other flaviviruses such as dengue virus or the Japanese encephalitis virus. In this study, we identified two new TMUV strains belonging to cluster 3, which seems to be endemic in rural areas of Thailand and highlighted the genetic specificities of this Thai cluster. Our results show the active circulation of this emerging flavivirus in Thailand and the need for continuous investigation on this poorly known but threatening virus in Asia.

Elevation of Pulmonary Artery Pressure in Newborns from High-Altitude Pregnancies Complicated by Preeclampsia.

We hypothesized that fetal exposure to the oxidative stress induced by the combined challenge of preeclampsia (PE) and high altitude would induce a significant impairment in the development of pulmonary circulation. We conducted a prospective study in La Paz (Bolivia, mean altitude 3625 m) in which newborns from singleton pregnancies with and without PE were compared (PE group n = 69, control n = 70). We conducted an echocardiographic study in these infants at the median age of two days. The percentage of cesarean deliveries and small for gestational age (SGA) infants was significantly higher in the PE group. Heart rate, respiratory rate, and oxygen saturation did not vary significantly between groups. Estimated pulmonary arterial pressure and pulmonary vascular resistance were 30% higher in newborns exposed to PE and high altitude compared with those exposed only to high altitude. We also detected signs of right ventricular hypertrophy in infants subjected to both exposures. In conclusion, this study provides evidence that the combination of PE and pregnancy at high altitude induces subclinical alterations in the pulmonary circulation of the newborn. Follow-up of this cohort may provide us with valuable information on the potential increased susceptibility to developing pulmonary hypertension or other pulmonary and cardiovascular disorders.

Update on temporal and spatial abundance of dengue vectors in Penang, Malaysia.

It is important to obtain frequent measurements of the abundance, distribution, and seasonality of mosquito vectors to determine the risk of disease transmission. The number of cases of dengue infection has increased in recent years on Penang Island, Malaysia, with recurring epidemics. However, ongoing control attempts are being critically hampered by the lack of up-to-date information regarding the vectors. To overcome this problem, we examined the current situation and distribution of dengue vectors on the island. Residences throughout the urban, suburban, and rural areas were inspected through wet and dry seasons between February 2009 and February 2010. Two vectors were encountered in the survey, with Aedes aegypti present in especially high numbers mostly in urban areas. Similar observations were noted for Ae. albopictus in rural areas. The former species was more abundant in outdoor containers, while the latter showed almost equivalent abundance both outdoors and indoors. The dengue virus was active in both urban and rural areas, and the number of cases of infection was higher in areas where Ae. aegypti was predominant. The abundance of immature Ae. albopictus was positively correlated with rainfall (r2 = 0.461; P < 0.05), but this was not the case for Ae. aegypti. For both species, the size of immature populations tended to increase with increasing intensity of rain, but heavy rains resulted in population loss. In addition to updating data regarding the larval habitats and locations (outdoors and indoors), this study highlighted the importance of spatial vector control stratification, which has the potential to reduce costs in control programs.

Detoxifying SARS-CoV-2 antiviral drugs from model and real wastewaters by industrial waste-derived multiphase photocatalysts.

The use of antiviral drugs has surged as a result of the COVID-19 pandemic, resulting in higher concentrations of these pharmaceuticals in wastewater. The degradation efficiency of antiviral drugs in wastewater treatment plants has been reported to be too low due to their hydrophilic nature, and an additional procedure is usually necessary to degrade them completely. Photocatalysis is regarded as one of the most effective processes to degrade antiviral drugs. The present study aims at synthesizing multiphase photocatalysts by a simple calcination of industrial waste from ammonium molybdate production (WU photocatalysts) and its combination with WO3 (WW photocatalysts). The X-ray diffraction (XRD) results confirm that the presence of multiple crystalline phases in the synthesized photocatalysts. UV-Vis diffuse reflectance spectra reveal that the synthesized multiphase photocatalysts absorb visible light up to 620 nm. Effects of calcination temperature of industrial waste (550-950 °C) and WO3 content (0-100%) on photocatalytic activity of multiphase photocatalysts (WU and WW) for efficient removal of SARS-CoV-2 antiviral drugs (lopinavir and ritonavir) in model and real wastewaters are studied. The highest k1 value is observed for the photocatalytic removal of ritonavir from model wastewater using WW4 (35.64 ×10-2 min-1). The multiphase photocatalysts exhibit 95% efficiency in the photocatalytic removal of ritonavir within 15 of visible light irradiation. In contrast, 60 min of visible light irradiation is necessary to achieve 95% efficiency in the photocatalytic removal of lopinavir. The ecotoxicity test using zebrafish (Danio rerio) embryos shows no toxicity for photocatalytically treated ritonavir-containing wastewater, and the contrary trend is observed for photocatalytically treated lopinavir-containing wastewater. The synthesized multiphase photocatalysts can be tested and applied for efficient degradation of other SARS-CoV-2 antiviral drugs in wastewater in the future.

Antioxidative systems defense against oxidative stress induced by blood meal in Aedes aegypti.

The release of iron from hemoglobin via the digestion of a blood meal in female mosquitoes can potentially induce oxidative damage and even death. These mosquitoes need an effective antioxidant to prevent this. We carried out this study to determine the antioxidant activities of ferritin, glutathione peroxidase (GPx), glutathione S-transferase (GST) and catalase, and glutathione (GSH). These enzymes had their greatest activity among 4 day old virgin female mosquitoes. Using a single blood feed model, groups of female mosquitoes were tested at 4, 7 and 20 days post-emergence. They were allowed to feed on a hamster for 1 hour. The engorged mosquitoes were collected at 48 and 72 hours after their blood meal. There were no changes in GSH, GPx, GST or catalase levels, but ferritin levels increased markedly (about 2-3 fold) by 48 hours post blood-feed in all mosquito age groups. On repeated blood-feed experiments, mosquitoes aged 4 days were blood fed, once every 3 days and were collected 48 hours after their most recent blood meal. A significant decrease in GSH and GPx activity and a further increase in ferritin, were detected. Ferritin levels were 0.19+/-0.03 and 0.14+/-0.02 ng/microg protein in the repeat and single blood-feed groups, respectively. These results suggest ferritin is an inducible, sensitive defense system protecting against oxidative stress caused by iron derived from blood meals in Aedes aegypti mosquitoes.

Fundamentals and applications of photoelectrocatalysis as an efficient process to remove pollutants from water: A review.

Water pollution is an environmental problem in constant raising because of population growing, industrial development, agricultural frontier expansion, and principally because of the lack of wastewater treatment technology to remove organic recalcitrant and toxic pollutants from industrial and domestic wastewater. Recalcitrant compounds are a serious environmental and health problem mainly due to their toxicity and potential hazardous effects on living organisms, including human beings. Conventional wastewater treatments have not been able to remove efficiently pollutants from water; however, electrochemical advanced oxidation processes (EAOPs) are able to solve this environmental concern. One of the most recent EAOPs technology is photoelectrocatalysis (PEC), it consists in applying an external bias potential to a semiconductor film placed over a conductive substrate to avoid the recombination of photogenerated electron-hole (e-/h+) pairs, increasing h+ availability and hydroxyl radicals' formation, responsible for promoting the degradation/mineralization of organic pollutants in aqueous medium. This review summarizes the recent advances in PEC as a promising technology for wastewater treatment. It addresses the fundamentals and kinetic aspects of PEC. An analysis of photoanode materials and of the configuration of photoelectrochemical reactors is also presented, including an analysis of the influence of the main operational parameters on the treatment of contaminated water. Finally, the most recent applications of PEC are reviewed, and the challenges and perspectives of PEC in wastewater treatment are discussed.

New Insights into the Biology of the Emerging Tembusu Virus.

Reported for the first time in 1955 in Malaysia, Tembusu virus (TMUV) remained, for a long time, in the shadow of flaviviruses with human health importance such as dengue virus or Japanese encephalitis virus. However, since 2010 and the first large epidemic in duck farms in China, the threat of its emergence on a large scale in Asia or even its spillover into the human population is becoming more and more significant. This review aims to report current knowledge on TMUV from viral particle organization to the development of specific vaccines and therapeutics, with a particular focus on host-virus interactions.

Zika Virus Potential Vectors among Aedes Mosquitoes from Hokkaido, Northern Japan: Implications for Potential Emergence of Zika Disease.

The Zika virus (ZIKV) is a rapidly expanding mosquito-borne virus that causes febrile illness in humans. Aedes aegypti and Ae. albopictus are the primary ZIKV vectors; however, the potential vector competence of other Aedes mosquitoes distributed in northern Japan (Palearctic ecozone) are not yet known. In this study, the susceptibility to Zika virus infection of three Aedes mosquitoes distributed in the main city of the northern Japan and their capacities as vectors for ZIKV were evaluated. Field-collected mosquitoes were fed ad libitum an infectious blood meal containing the ZIKV PRVABC59. The Zika virus was detected in the abdomen of Ae. galloisi and Ae. japonicus at 2-10 days post infection (PI), and from the thorax and head of Ae. galloisi at 10 days PI, resulting in 17.6% and 5.9% infection rates, respectively. The Zika virus was not detected from Ae. punctor at any time. Some northern Japanese Aedes could be suspected as vectors of ZIKV but the risk may be low when compared with major ZIKV vectors.

Flower Mimics Roll Out Multicolored Carpets to Lure and Kill the House Fly.

Flowers and their spatial clustering are important parameters that mediate the foraging behavior and visitation rate of pollinating insects. Visual stimuli are crucial for triggering behavioral changes in the house fly, Musca domestica, which regularly visits plants for feeding and reproduction. The success of bait technology, which is the principal means of combatting flies, is adversely affected by reduced attractiveness and ineffective application techniques. Despite evidence that house flies have color vision capacity, respond to flowers, and exhibit color and pattern preference, the potential of artificial flowers as attractive factors has not been explored. The present study was performed to investigate whether artificial floral designs can lure and kill house flies. Starved wild house flies were presented with equal opportunities to acquire sugar meals, to which boric acid had been added as a toxin, from one flower arrangement (blue-dominated design, BDD; yellow-dominated design, YDD; or pink-dominated design, PDD), and a non-toxic white design (WDD). We also allowed house flies to forage within an enclosure containing two non-toxic floral designs (WDDs). The differences in mortality between the two environments with and without toxicant were examined. The survival rate of Musca domestica was extremely high when WDDs containing non-toxic sugar sources were the only feeding sites available. When given an option to forage in an environment containing a BDD and a WDD, house flies showed a high mortality rate (76%) compared to their counterparts maintained in the WDD environment (2%). When kept in an enclosure containing one YDD and a WDD, flies showed a mortality rate of 88%; however, no mortality occurred among flies confined to a compound with a WDD pair. When provided an even chance of foraging in an enclosure containing a mixed pair of floral arrangements (PDD and WDD) and another with two WDDs, flies showed a higher mortality rate (78%) in the first environment. However, the maximum survival rate (100%) was seen in the WDD environment. Exposure to YDD tended to result in a greater mortality rate than with the two other floral designs. Mortality gradually increased with time among flies exposed to tested artificial floral designs. The results presented here clearly indicated that artificial flower arrangements with a toxic sugar reward were strikingly attractive for house flies when their preferred color (white) was present. These observations offer novel possibilities for future development of flower mimic-based house fly control.