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Article Highlights - Effective induction of PLBs from stem thin layer and shoot regeneration using specific BAP and auxin combinations. - Significant role of potato extract in enhancing shoot regeneration. - Highest shoot regeneration rate achieved with 3 mg/L BAP concentration. Abstract Anubias barteri var. nana Petite, a highly valued ornamental aquatic plant in the Araceae family, faces challenges in vegetative propagation due to its slow multiplication rate. This study established a robust micropropagation protocol for rapid and efficient multiplication of A. barteri var. nana Petite. Explants were subjected to thorough sterilization, and shoot induction and multiplication were optimized using varying concentrations of Benzyl adenine (BA) on Murashige and Skoog (MS) medium. Protocorm-like bodies (PLBs) were induced from transverse thin-layer explants using combinations of BAP and Naphthaleneacetic acid (NAA). PLB multiplication and shoot regeneration were achieved through a sequential culture protocol. In addition, the influence of potato extract on shoot regeneration and the role of Indole-3-butyric Acid (IBA) in root development were explored. This study demonstrated a 100% survival rate of regenerated shoots in aquariums. Ongoing research is focused on further enhancing PLB multiplication. This optimized micropropagation protocol holds promise for the large-scale production of A. barteri var. nana Petite, addressing the limitations of natural propagation.

This study investigated the dual role of Streptomyces rochei BT02 in promoting tomato growth and suppressing Fusarium solani, the causative agent of tomato root rot disease. Various assays were conducted to evaluate the plant growth-promoting attributes of strain BT02 including indole-3-acetic acid (IAA) biosynthesis, phosphate solubilization, biofilm formation, and siderophore production. Under in vitro conditions, strain BT02 exhibited plant growth-promoting characteristics such as cellulose degradation, phosphate solubilization, IAA synthesis, biofilm formation, and siderophore production. Application of strain BT02 significantly improved tomato seed germination (26.7%), with enhanced sprout and radicle lengths and seed vigor (38.6%). Greenhouse experiments revealed substantial increases in plant height, leaf and branch numbers, inflorescence, and flower number, emphasizing the positive impact of strain BT02 on overall plant growth. The BT02 strain demonstrated antagonistic efficacy of 45.3 to 58.9% against Fusarium solani, as evidenced by the dual culture and agar well diffusion methods. Under greenhouse conditions, strain BT02 significantly reduced disease incidence and demonstrated control efficacy of 41.6% against Fusarium solani, highlighting its biocontrol potential. This study provides insights into the mechanisms employed by Streptomyces rochei BT02 to enhance plant growth and suppress root rot disease, paving the way for its application as a biocontrol agent in sustainable agriculture.

Abstract Climate-driven changes in precipitation amounts and their seasonal variability are expected in many continental-scale regions during the remainder of the 21st century. However, much less is known about future changes in the predictability of seasonal precipitation, an important earth system property relevant for climate adaptation. Here, on the basis of CMIP6 models that capture the present-day teleconnections between seasonal precipitation and previous-season sea surface temperature (SST), we show that climate change is expected to alter the SST-precipitation relationships and thus our ability to predict seasonal precipitation by 2100. Specifically, in the tropics, seasonal precipitation predictability from SSTs is projected to increase throughout the year, except the northern Amazonia during boreal winter. Concurrently, in the extra-tropics predictability is likely to increase in central Asia during boreal spring and winter. The altered predictability, together with enhanced interannual variability of seasonal precipitation, poses new opportunities and challenges for regional water management.

Groundwater is a critical component of water resources and has become the primary water supply for agricultural and domestic uses in the Vietnamese Mekong Delta (VMD). Widespread groundwater level declines have occurred in the VMD over recent decades, reflecting that extraction rates exceed aquifer recharge in the region. However, the impacts of climate variability on groundwater system dynamics in the VMD remain poorly understood. Here, we explore recent changes in groundwater levels in shallow and deep aquifers from observed wells in the VMD and investigate their relations to the annual precipitation variability and El Niño–Southern Oscillation (ENSO). We show that groundwater level responds to changes in annual precipitation at time scales of approximately 1 year. Moreover, shallow (deep) groundwater in the VMD appears to correlate with the ENSO over intra-annual (inter-annual) time scales. Our findings reveal a critical linkage between groundwater level changes and climate variability, suggesting the need to develop an understanding of the impacts of climate variability across time scales on water resources in the VMD. HIGHLIGHTS The connections between groundwater level change and climate variability in the Vietnamese Mekong Delta (VMD) are examined using vector autoregression and wavelet analysis.; Groundwater level response to changes in annual precipitation in the VMD is largest within the first year.; Groundwater level in shallow (deep) aquifers in the VMD appears to correlate with ENSO over intra-annual (inter-annual) time scales.;

Interferometric synthetic aperture radar (InSAR), one of the most commonly used remote sensing methods for observing and monitoring land subsidence, has been applied in Hanoi, Vietnam in several studies with results showing deformation up to 2014. However, freely accessible Sentinel-1 InSAR data have not been investigated thoroughly to date. Here, we investigate the most recent land surface deformation in Hanoi for the period 2016$$ - $$2020 using Sentinel-1A SAR data. The analysis is conducted on 114 SAR scenes with both the Persistent Scatterer InSAR (PSInSAR) and Small BAseline Subset (SBAS) methods. The GPS-based deformation time series are used to verify InSAR results and borehole groundwater level measurements are employed to evaluate the relationship between groundwater depletion and surface subsidence. The results show that observed deformation from SBAS and PSInSAR is consistent in both spatial patterns and statistics, in which two high-rate subsiding bowls were detected in Dan Phuong/Hoai Duc and Ha Dong/Thanh Tri districts with the mean subsiding rates of ∼5 mm per year. GPS and InSAR deformation generally agree well except for the comparison at the JNAV station after 2017, which can be attributable to the local deformation detected by GPS and the average movement of a 100-m radius area captured by InSAR. An agreement in the drawdown trend between borehole groundwater and InSAR-derived deformation was found at four wells located within or in proximity to the two bowls. The declining rates of groundwater level at about 0.31 m per year were found at the two wells Q57a and Q58a located within the Dan Phuong/Hoai Duc bowl, corresponding to the surface subsidence rates found at 6–8 mm per year. The Q68a well was found to experience groundwater level declining at the highest rate of ∼0.9 m per year corresponding to the subsidence rate of ∼7 mm per year found by InSAR.

At the RIKEN Nishina Center, exotic neutron-rich isotopes of Ba, La, Ce, Pr, and Nd were measured. This work reports their half-lives (T1/2) and β-delayed neutron-emission probabilities (Pxn). The setup consisted of the BigRIPS in-flight separator for particle identification, the Advanced Implantation Detector Array (AIDA) for ions and β detection, and the BRIKEN neutron counter for neutron detection. Using this arrangement, 4 new T1/2 and 14 new P1n were measured. Furthermore, 38 T1/2 and 2 P1n values were remeasured, decreasing the uncertainties for some of them. In addition to improving predictions of nucleosynthesis models that describe the production of the rare-earth peak at A ∼ 160 via the r-process, these additional experimental data should help to constrain theoretical models for calculations of T1/2 and Pxn in this region.

Half-lifes (T1/2) of exotic neutron-rich isotopes of Ba, La, Ce, Pr, and Nd were measured at the RIKEN Nishina Center. The experimental setup consisted of the BigRIPS in-flight separator for ion selection identification, the Advance Implantation Detector Array (AIDA) for ions and β detection, and the BRIKEN detector for neutron counting. Using this setup, 4 new T1/2 have been measured for the first time, and 38 T1/2 have been remeasured with improved precision in several cases. These new experimental data should help to constrain theoretical models for calculations of T1/2. The status of the experimental analysis and preliminary results are provided in this contribution.

The very proton-rich 71Kr isotope was produced through the in-flight fragmentation of 78Kr on a beryllium target at RIKEN – Nishina Center in order to study its β-decay properties. A stack of double-sided silicon strip detectors, called WAS3ABi, was used as the decay station, where the detection of ion implants, β-decays and β-delayed protons took place. Beta-delayed γ-rays were measured using a system of 84 HPGe detectors, called EURICA, surrounding the decay station. The main goal of the present study was the precise measurement of the half-life of 71Kr, as in the literature there is an almost 10 σ difference between the most precise independent results. Implant–β time correlations, implant–proton time correlations and implant–β–γ time correlations were all used to derive the half-life value, followed by a thorough investigation of systematic uncertainties for each method. As these values were found to be consistent, the weighted average t1/2 = 94.40+19ms is reported as a new half-life value in this work. Furthermore a total of 26 previously unreported γ following the β-decay of 71Kr were also identified in the analysis.

Abstract Background The transmission of malaria is highly variable and depends on a range of climatic and anthropogenic factors. In addition, the dispersal of Anopheles mosquitoes is a key determinant that affects the persistence and dynamics of malaria. Simple, lumped-population models of malaria prevalence have been insufficient for predicting the complex responses of malaria to environmental changes. Methods and results A stochastic lattice-based model that couples a mosquito dispersal and a susceptible-exposed-infected-recovered epidemics model was developed for predicting the dynamics of malaria in heterogeneous environments. The It$$\hat{o}$$ o^ approximation of stochastic integrals with respect to Brownian motion was used to derive a model of stochastic differential equations. The results show that stochastic equations that capture uncertainties in the life cycle of mosquitoes and interactions among vectors, parasites, and hosts provide a mechanism for the disruptions of malaria. Finally, model simulations for a case study in the rural area of Kilifi county, Kenya are presented. Conclusions A stochastic lattice-based integrated malaria model has been developed. The applicability of the model for capturing the climate-driven hydrologic factors and demographic variability on malaria transmission has been demonstrated.

Experimental studies on astrophysical reactions involving radioactive isotopes (RI) often accompany technical challenges. Studies on such nuclear reactions have been conducted at the low-energy RI beam separator CRIB, operated by Center for Nuclear Study, the University of Tokyo. We discuss two cases of astrophysical reaction studies at CRIB; one is for the 7Be+n reactions which may affect the primordial 7Li abundance in the Big-Bang nucleosynthesis, and the other is for the 22Mg(α, p) reaction relevantin X-raybursts.

BACKGROUND:The transmission of malaria is highly variable and depends on a range of climatic and anthropogenic factors. This study investigates the combined, i.e. direct and indirect, impacts of climate change on the dynamics of malaria through modifications in: (i) the sporogonic cycle of Plasmodium induced by air temperature increase, and (ii) the life cycle of Anopheles vector triggered by changes in natural breeding habitat arising from the altered moisture dynamics resulting from acclimation responses of vegetation under climate change. The study is performed for a rural region in Kilifi county, Kenya. METHODS AND FINDINGS:We use a stochastic lattice-based malaria (SLIM) model to make predictions of changes in Anopheles vector abundance, the life cycle of Plasmodium parasites, and thus malaria transmission under projected climate change in the study region. SLIM incorporates a nonlinear temperature-dependence of malaria parasite development to estimate the extrinsic incubation period of Plasmodium. It is also linked with a spatially distributed eco-hydrologic modeling framework to capture the impacts of climate change on soil moisture dynamics, which served as a key determinant for the formation and persistence of mosquito larval habitats on the land surface. Malaria incidence data collected from 2008 to 2013 is used for SLIM model validation. Projections of climate change and human population for the region are used to run the models for prediction scenarios. Under elevated atmospheric CO2 concentration ([CO2]) only, modeled results reveal wetter soil moisture in the root zone due to the suppression of transpiration from vegetation acclimation, which increases the abundance of Anopheles vectors and the risk of malaria. When air temperature increases are also considered along with elevated [CO2], the life cycle of Anopheles vector and the extrinsic incubation period of Plasmodium parasites are shortened nonlinearly. However, the reduction of soil moisture resulting from higher evapotranspiration due to air temperature increase also reduces the larval habitats of the vector. Our findings show the complicated role of vegetation acclimation under elevated [CO2] on malaria dynamics and indicate an indirect but ignored impact of air temperature increase on malaria transmission through reduction in larval habitats and vector density. CONCLUSIONS:Vegetation acclimation triggered by elevated [CO2] under climate change increases the risk of malaria. In addition, air temperature increase under climate change has opposing effects on mosquito larval habitats and the life cycles of both Anopheles vectors and Plasmodium parasites. The indirect impacts of temperature change on soil moisture dynamics are significant and should be weighed together with the direct effects of temperature change on the life cycles of mosquitoes and parasites for future malaria prediction and control.

The commissioning of a new setup for β-delayed neutron measurements was carried out successfully in November-2016, at the RIKEN Nishina Center in Japan. The β-decay half-lives and Pn branching ratios of several isotopes in the 78Ni region were measured. Details of the experimental setup and the first results are given.

Climate-driven changes in precipitation amounts and their seasonal variability are expected in many continental-scale regions during the remainder of the 21st century. However, much less is known about future changes in the predictability of seasonal precipitation, an important earth system property relevant for climate adaptation. Here, on the basis of CMIP6 models that capture the present-day teleconnections between seasonal precipitation and previous-season sea surface temperature (SST), we show that climate change is expected to alter the SST-precipitation relationships and thus our ability to predict seasonal precipitation by 2100. Specifically, in the tropics, seasonal precipitation predictability from SSTs is projected to increase throughout the year, except the northern Amazonia during boreal winter. Concurrently, in the extra-tropics predictability is likely to increase in central Asia during boreal spring and winter. The altered predictability, together with enhanced interannual variability of seasonal precipitation, poses new opportunities and challenges for regional water management. This study shows that climate change will alter the sea surface temperature - precipitation relationships and our ability to predict seasonal precipitation by 2100. [ABSTRACT FROM AUTHOR]

In this study, the spatiotemporal variability of drought over the entire Southeast Asia (SEA) region and its associations with the large-scale climate drivers during the period 1960–2019 are investigated for the first time. The 12-month Standardized Precipitation Evapotranspiration Index (SPEI) was computed based on the monthly Global Precipitation Climatology Centre (GPCC) precipitation and the monthly Climate Research Unit (CRU) 2-m temperature. The relationships between drought and large-scale climate drivers were examined using the principal component analysis (PCA) and maximum covariance analysis (MCA) techniques. Results showed that the spatiotemporal variability of drought characteristics over SEA is significantly different between mainland Indochina and the Maritime Continent and the difference has been increased substantially in recent decades. Moreover, the entire SEA is divided into four homogeneous drought subregions. Drought over SEA is strongly associated with oceanic and atmospheric large-scale drivers, particularly El Nino˜ –Southern Oscillation (ENSO), following by other remote factors such as the variability of sea surface temperature (SST) over the tropical Atlantic, the Pacific decadal oscillation (PDO), and the Indian Ocean dipole mode (IOD). In addition, there exists an SST anomaly dipole over the Pacific Ocean, which modulates the atmospheric circulations and consequently precipitation over SEA, affecting drought conditions in the study region. [ABSTRACT FROM AUTHOR]

Summary: The root-knot nematodes (RKN) Meloidogyne graminicola and M. incognita are responsible for rice yield losses worldwide, particularly in Asia and Africa. Previous studies demonstrated that nematode-secreted proteins are crucial for root invasion and establishment in the host. We present some characteristics of a pioneer effector, M. incognita- secreted protein 4 (Mi-SP4), which is conserved in RKN and required for infection in compatible rice-RKN interactions. In situ hybridisation assays revealed Mi-SP4 expression in the dorsal pharyngeal gland of M. incognita second-stage juveniles (J2). Meloidogyne - SP4 transcripts strongly accumulated in pre-parasitic J2 and decreased in later parasitic stages of M. incognita and M. graminicola. Transient expression of the nematode effector gene in Nicotiana benthamiana leaves and onion cells indicated that GFP-tagged Mi-SP4 was present in the cytoplasm and accumulated in the nucleus of the plant cells. In vitro RNA interference (RNAi) gene silencing, obtained by soaking J2 with small-interfering (si)RNA si4-1, decreased Mi - SP4 expression in J2 by 35% and significantly reduced M. incognita reproduction in rice by at least 30%. Similarly, host-mediated gene silencing of the nematode SP4 effector candidate gene in transgenic rice plants significantly reduced M. graminicola reproduction by 26% to 47%. The data obtained demonstrate that Mi -SP4 is a pioneer virulence effector, which plays an essential role in both M. incognita and M. graminicola pathogenicity on rice. [ABSTRACT FROM AUTHOR]

Xao tam phan (Paramignya trimera (Oliv.) Guillaum) is a medicinal plant native to Vietnam, that is renowned for its therapeutic properties, particularly for the treatment of various ailments, including cancer. This study investigated in vitro propagation of P. trimera through somatic embryogenesis and shoot organogenesis using leaf callus. Various culture media, plant growth regulators, malt extract, and carbon sources were evaluated to optimize callus induction and somatic embryo formation from leaf explants. DNA barcoding confirmed 96.96% to 100% homology with P. trimera specimens from Khanh Hoa province, Vietnam. The highest callus formation rate, reaching 100%, was observed in one-year-old explants cultured in Woody Plant Medium (WPM) supplemented with 2.0 mg L-1 naphthaleneacetic acid (NAA) and 0.2 mg L-1 benzylaminopurine (BAP) in the dark for over six weeks. In WPM supplemented with 30 g L-1 sucrose, 4.0 mg L-1 BAP, and 500 mg L-1 malt extract, globular stage embryos developed into embryoids and shoots and buds clumped at 10 and 18 weeks, respectively. Shoot organogenesis was observed in WPM supplemented with 30 g L-1 sucrose and 0.07 mg L-1 thidiazuron (TDZ) after 18 weeks of culture. Genetic fidelity assessments using 12 SCoT markers indicated that in vitro plantlets were homologous to the mother plant. This study provides a viable method for the conservation and sustainable cultivation of Xao tam phan, ensuring a stable supply of this valuable medicinal resource.

Groundwater is a critical component of water resources and has become the primary water supply for agricultural and domestic uses in the Vietnamese Mekong Delta (VMD). Widespread groundwater level declines have occurred in the VMD over recent decades, reflecting that extraction rates exceed aquifer recharge in the region. However, the impacts of climate variability on groundwater system dynamics in the VMD remain poorly understood. Here, we explore recent changes in groundwater levels in shallow and deep aquifers from observed wells in the VMD and investigate their relations to the annual precipitation variability and El Niño-Southern Oscillation (ENSO). We show that groundwater level responds to changes in annual precipitation at time scales of approximately 1 year. Moreover, shallow (deep) groundwater in the VMD appears to correlate with the ENSO over intra-annual (inter-annual) time scales. Our findings reveal a critical linkage between groundwater level changes and climate variability, suggesting the need to develop an understanding of the impacts of climate variability across time scales on water resources in the VMD. [ABSTRACT FROM AUTHOR]

Summary: The rice root-knot nematode, Meloidogyne graminicola , is a serious pathogen of rice production worldwide. In Vietnam, scientific information on the rice root-knot nematode is limited. In this circumstance, our study aimed to investigate the characteristics of M. graminicola from rice fields in southern Vietnam and to evaluate the reaction of 20 rice varieties to this soil-borne pathogen in a glasshouse experiment. Ten populations of root-knot nematode collected from rice fields at different geographical regions in the Mekong Delta were identified as M. graminicola based on the perineal configuration of females and species-specific molecular markers. The morphological, morphometric and molecular characteristics of ten nematode isolates were defined, and the variations observed between these isolates were not significantly different. The pathogenicity of these isolates was examined in the susceptible Indica rice, Oryza sativa 'IR64', with a reproduction factor ranging from 18.1 to 37.8. Of the 20 Indica rice varieties tested in response to the nematode population MG-PN08, the 'Tetep' variety showed moderate resistance to the nematode (reproductive factor = 11.7; galling index = 2.4), while others were ranked at levels ranging from moderately susceptible to highly susceptible. The life cycle of M. graminicola in 'Tetep' root is 28 days compared to 21 in 'IR64'. 'Tetep'-nematode interaction at the histological and molecular levels needs further investigation to develop new rice varieties resistant to rice root-knot nematode. [ABSTRACT FROM AUTHOR]

The Madden‐Julian Oscillation (MJO) is the leading mode of intraseasonal climate variability, having profound impacts on a wide range of weather and climate phenomena. Here, we use a wavelet‐based spectral Principal Component Analysis (wsPCA) to evaluate the skill of 20 state‐of‐the‐art CMIP6 models in capturing the magnitude and dynamics of the MJO. By construction, wsPCA has the ability to focus on desired frequencies and capture each propagative physical mode with one principal component (PC). We show that the MJO contribution to the total intraseasonal climate variability is substantially underestimated in most CMIP6 models. The joint distribution of the modulus and angular frequency of the wavelet PC series associated with MJO is used to rank models relatively to the observations through the Wasserstein distance. Using Hovmöller phase‐longitude diagrams, we also show that precipitation variability associated with MJO is underestimated in most CMIP6 models for the Amazonia, Southwest Africa, and Maritime Continent. Plain Language Summary: Dominant modes (i.e., coherent spatio‐temporal patterns of variability) of the climate system, such as the Madden‐Julian Oscillation (MJO), influence a wide range of weather and climate phenomena worldwide. The ability of state‐of‐the‐art climate models to accurately simulate these modes is crucial for advancing our understanding of the climate system and reliably predicting its future trends. The Coupled Model Intercomparison Project Phase 6 (CMIP6) will be the foundation for the upcoming Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6). Here, we use a wavelet‐based spectral principal component analysis (wsPCA) to quantitatively assess how well historical simulations from 20 CMIP6 models capture MJO as compared to the observations. We first show that the MJO magnitude is not reproduced well in most of CMIP6 models. We then reveal that MJO‐related precipitation variability in the Amazonia, Southwest Africa, and Maritime Continent is significantly underestimated in many CMIP6 models. Our results highlight the need to better simulate the coupled ocean‐atmosphere dynamics in order to improve the representation of MJO in climate models and increase confidence in projected states of MJO for assessing future tropical and extratropical impacts. Key Points: A wavelet‐based spectral principal component analysis is used to examine CMIP6 models in reproducing the Madden‐Julian Oscillation (MJO)CMIP6 models capture the average MJO propagation speed but significantly underestimate the MJO contribution to the total intraseasonal climate variabilityPrecipitation variability related to MJO over the Amazonia, Southwest Africa, and Maritime Continent is underestimated in CMIP6 models [ABSTRACT FROM AUTHOR]

Beta-decay of the very neutron-deficient Kr isotope, 70Kr, was studied at RIKEN-RIBF using the EURICA cluster array. The experiment significantly increased our knowledge of the beta-decay of this isotope. Namely, 16 new γ-ray transitions were identified and the half-life was derived from time correlations of the beta particles (tiβ 1/2 = (44.99±0.16) ms) and from thedecaycurvesoftheobserved γ-raytransitions(tiβγ 1/2 = (45.16±0.71) ms), respectively. [ABSTRACT FROM AUTHOR]

BackgroundDietary and lifestyle habits related to troublesome gastroesophageal reflux symptoms (tGERS) differ significantly across populations. There have yet to be studies on the Vietnamese population.AimsTo identify dietary and lifestyle habits associated with tGERS in Vietnamese adults.MethodsA cross-sectional survey was conducted among Vietnamese adults aged 18 years and older from March 2023 to May 2023. Participants were recruited online through a widely read national newspaper and Facebook, one of Vietnam’s most popular social media platforms. The survey questionnaire comprised 27 questions covering participants’ basic demographic information, dietary and lifestyle habits, the presence and characteristics of tGERS, and inquiries about specific dietary and lifestyle patterns, foods, and beverages associated with tGERS.ResultsA total of 4,400 valid responses were collected, including 2050 participants without tGERS and 2,350 participants with tGERS. Multivariate analysis showed several factors associated with tGERS, including eating beyond fullness (OR 1.383, CI95% 1.127–1.698), tight clothing (OR 1.627, CI95% 1.256–2.107), stress (OR 1.566, CI95% 1.363–1.800), and insomnia (OR 1.321, CI95% 1.129–1.546). Among habits associated with tGERS, eating beyond fullness was the most frequently reported (64.6%). Interestingly, although a short meal-to-bed time and staying up late after midnight were not risk factors for tGERS, they were two common factors associated with tGERS in symptomatic participants, particularly those with nocturnal reflux symptoms. For food triggers, the three most common ones were greasy foods (71.9%), sour/spicy soups (64.7%), and citrus fruits (36.0%). In terms of beverages, carbonated soft drinks were at the top of triggering tGERS (40.3%), and beer and orange juice were the second and third most common triggers, accounting for 35.7 and 30.6%, respectively.ConclusionWe reported the dietary and lifestyle habits associated with tGERS in Vietnamese adults for the first time. These findings will serve as a basis for future studies on the primary prevention and nondrug management of tGERS in Vietnam.

Drought may have severe societal, economic, and environmental consequences. However, the space–time characteristics of drought over Vietnam remain poorly understood. In this study, we investigate the spatio‐temporal variability of drought using the Palmer Drought Severity Index (PDSI) over mainland Vietnam for the 1980–2014 period. Through data analysis at 131 stations, we identified the main characteristics, historical trends, and dominant variability of drought across seven climatic sub‐regions in Vietnam. The results show regional patterns of drought duration, inter‐arrival time, frequency, and severity, but no consistent trend of drought variation during the study period. Based on the supply and demand concepts of water balance, PDSI captures well the large frequency and severity of drought in some sub‐regions that are related to soil moisture deficit associated with high temperature and low rainfall during summer. Moreover, drought over Vietnam was predominantly controlled by climate seasonality. The linkages between drought in Vietnam and large‐scale drivers are quite different among areas, suggesting a possibility of early prediction for drought at some sub‐regions using ENSO. [ABSTRACT FROM AUTHOR]

Our understanding of the evolution of the shell structure in nuclei far from stability is based on the study of some key nuclei. Nuclei at or next to double shell closures play a special role in this. Presently, a lot of discussion is concentrated on the neutron-rich calcium isotopes, which provide a rich testing ground for various nuclear models with several traditional and new magic numbers. 60Ca is now almost within reach with the most advanced radioactive beam facilities. In order to investigate the evolution of the shell gap at N = 40, the configuration of states in the odd-even titanium isotopes up to N = 37 (59Ti) have been studied. In order to experimentally access the shell gap at N = 40, it is nowadays within the reach of the most advanced facility the investigation of neutron hole configuration states in odd-even titanium isotopes up to N = 37, in the 59Ti nucleus. Such states correspond to relatively simple configurations that constitute a challenging testing ground for effective nuclear interactions. The new data obtained in our experiment allows to place the present predictions concerning the shell closure at N = 40 in the calcium region on a more solid ground. [ABSTRACT FROM AUTHOR]

Background: The transmission of malaria is highly variable and depends on a range of climatic and anthropogenic factors. This study investigates the combined, i.e. direct and indirect, impacts of climate change on the dynamics of malaria through modifications in: (i) the sporogonic cycle of Plasmodium induced by air temperature increase, and (ii) the life cycle of Anopheles vector triggered by changes in natural breeding habitat arising from the altered moisture dynamics resulting from acclimation responses of vegetation under climate change. The study is performed for a rural region in Kilifi county, Kenya. Methods and findings: We use a stochastic lattice-based malaria (SLIM) model to make predictions of changes in Anopheles vector abundance, the life cycle of Plasmodium parasites, and thus malaria transmission under projected climate change in the study region. SLIM incorporates a nonlinear temperature-dependence of malaria parasite development to estimate the extrinsic incubation period of Plasmodium. It is also linked with a spatially distributed eco-hydrologic modeling framework to capture the impacts of climate change on soil moisture dynamics, which served as a key determinant for the formation and persistence of mosquito larval habitats on the land surface. Malaria incidence data collected from 2008 to 2013 is used for SLIM model validation. Projections of climate change and human population for the region are used to run the models for prediction scenarios. Under elevated atmospheric CO2 concentration ([CO2]) only, modeled results reveal wetter soil moisture in the root zone due to the suppression of transpiration from vegetation acclimation, which increases the abundance of Anopheles vectors and the risk of malaria. When air temperature increases are also considered along with elevated [CO2], the life cycle of Anopheles vector and the extrinsic incubation period of Plasmodium parasites are shortened nonlinearly. However, the reduction of soil moisture resulting from higher evapotranspiration due to air temperature increase also reduces the larval habitats of the vector. Our findings show the complicated role of vegetation acclimation under elevated [CO2] on malaria dynamics and indicate an indirect but ignored impact of air temperature increase on malaria transmission through reduction in larval habitats and vector density. Conclusions: Vegetation acclimation triggered by elevated [CO2] under climate change increases the risk of malaria. In addition, air temperature increase under climate change has opposing effects on mosquito larval habitats and the life cycles of both Anopheles vectors and Plasmodium parasites. The indirect impacts of temperature change on soil moisture dynamics are significant and should be weighed together with the direct effects of temperature change on the life cycles of mosquitoes and parasites for future malaria prediction and control. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) is going through rapid reorganization due to anthropogenic influences. Understanding how biogeochemical transformation and erosion‐induced SOC redistribution influence SOC profiles and stocks is critical to our food security and adaptation to climate change. The important roles of erosion and deposition on SOC dynamics have drawn increasing attention in the past decades, but quantifying such dynamics is still challenging. Here we develop a process‐based quasi 3‐D model that couples surface runoff, soil moisture dynamics, biogeochemical transformation, and landscape evolution. We apply this model to a subcatchment in Iowa to understand how natural forcing and farming practices affect the SOC dynamics in the critical zone. The net soil thickness and SOC stock change rates are −0.336 (mm/yr) and −1.9 (g C/m2/year), respectively. Our model shows that in a fast transport landscape, SOC transport is the dominant control on SOC dynamics compared to biogeochemical transformation. The SOC profiles have "noses" below the surface at depositional sites, which are consistent with cores sampled at the same site. Generally, erosional sites are local net atmospheric carbon sinks and vice versa for depositional sites, but exceptions exist as seen in the simulation results. Furthermore, the mechanical soil mixing arising from tillage enhances SOC stock at erosional sites and reduces it at depositional ones. This study not only helps us understand the evolution of SOC stock and profiles in a watershed but can also serve as an instrument to develop practical means for protecting carbon loss due to human activities. Plain Language Summary: Understanding how soil organic carbon (SOC) content changes in space and time are critical for our food security and adaptation to climate change. It changes through the belowground transformation—decomposition of litter and release of CO2, and surficial transport—lateral physical redistribution. The balance between the two interactions has been strongly shifted by human activities. Quantifying such interactions has remained challenging. Here we developed a 3‐D model, which simulates the movement and burial of SOC and compare the impacts of natural and human activities in the critical zone. We apply this model to a watershed in Iowa. Our results show that the net soil thickness and SOC stock change rates are both decreasing. The fast burial of legacy carbon by modern carbon results in a "nose" profile at depositional sites, which is consistent with soil cores sampled in the watershed. The lateral transport rate can be significantly larger than the transformation rate, but this balance is modified by the mechanical mixing from tillage. Generally, erosional sites are net sinks for atmospheric carbon and depositional sites are net sources. The model can serve as an important tool for protecting soil carbon change caused by both human and natural events. Key Points: A process‐based 3‐D model is developed to simulate the coevolution of soil organic carbon (SOC) and landscape in a watershedVertical SOC profiles evolve heterogeneously across the watershed due to SOC redistribution and biogeochemical transformationGenerally, erosion and deposition sites are local net atmospheric C sinks and sources, respectively, but exceptions exist [ABSTRACT FROM AUTHOR]

Abstract: Natural wetlands are ecological, biogeochemical, and hydrological hot spots yet continue to disappear under human pressure. Their shapes and sizes control their hydroecological functions. We propose that elevation data can be used to delineate potential wetlands and that the (statistical) distributions of potential wetlands should be identical to the distributions of actual wetlands. We compare the shape and size distributions of wetlands reported in the National Wetland Inventory with those of potential wetlands identified using a topographic depression identification model. We estimated area and perimeter distributions as well as shoreline fractal dimension in six contrasting locations in the United States. Pareto distributions described the tails of these distributions, with similar slopes for both model and data. The shape of shorelines was also similar, and their fractal dimension clustered around D = 4/3, a pervasive value in nature. We also analyzed the entire wetland inventory data set for the conterminous United States (~20 million wetlands) for reference and found the statistics to be invariant across scales. Our results demonstrate that a simple topographic model can identify most reported wetlands as well as potential wetlands missing from the inventory. These findings could inform strategic surveys and the conservation of wetlandscapes. [ABSTRACT FROM AUTHOR]

Abstract Background Dengue virus (DENV) is a mosquito-borne arbovirus transmitted by Aedes mosquitoes, but is not endemic in all areas where this vector is found. For example, the relatively sparse distribution of cases in West Africa is generally attributed to the refractory nature of West African Aedes aegypti (Ae. aegypti) to DENV infection, and particularly the forest-dwelling Ae. aegypti formosus. However, recent studies have shown these mosquitoes to be competent vectors within some West African countries that have suffered outbreaks in the past, such as Senegal. There is however little information on the vector competence of the Ae. aegypti in West African countries such as Ghana with no reported outbreaks. Methods This study examined the vector competence of 4 Ae. aegypti colonies from urban, semi-urban, and two rural locations in Ghana in transmitting DENV serotypes 1 and 2, using a single colony from Vietnam as control. Midgut infection and virus dissemination were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR), while the presence and concentration of DENV in the saliva of infectious mosquitoes was determined by the focus forming assay. Results There were significant differences in the colonies’ susceptibility to virus infection, dissemination, and transmission. All examined Ghanaian mosquitoes were refractory to infection by DENV serotype 2, while some colonies exhibited potential to transmit DENV serotype 1. None of the tested colonies were as competent as the control group colony. Conclusions These findings give insight into the possible risk of outbreaks, particularly in the urban areas in the south of Ghana, and highlight the need for continuous surveillance to determine the transmission status and outbreak risk. This study also highlights the need to prevent importation of different DENV strains and potential invasion of new highly vector-competent Ae. aegypti strains, particularly around the ports of entry. Graphic Abstract

Vegetation acclimation resulting from elevated atmospheric CO2 concentration, along with response to increased temperature and altered rainfall pattern, is expected to result in emergent behavior in ecologic and hydrologic functions. We hypothesize that microtopographic variability, which are landscape features typically of the length scale of the order of meters, such as topographic depressions, will play an important role in determining this dynamics by altering the persistence and variability of moisture. To investigate these emergent ecohydrologic dynamics, we develop a modeling framework, Dhara, which explicitly incorporates the control of microtopographic variability on vegetation, moisture, and energy dynamics. The intensive computational demand from such a modeling framework that allows coupling of multilayer modeling of the soil-vegetation continuum with 3-D surface-subsurface flow processes is addressed using hybrid CPU-GPU parallel computing framework. The study is performed for different climate change scenarios for an intensively managed agricultural landscape in central Illinois, USA, which is dominated by row-crop agriculture, primarily soybean ( Glycine max) and maize ( Zea mays). We show that rising CO2 concentration will decrease evapotranspiration, thus increasing soil moisture and surface water ponding in topographic depressions. However, increased atmospheric demand from higher air temperature overcomes this conservative behavior resulting in a net increase of evapotranspiration, leading to reduction in both soil moisture storage and persistence of ponding. These results shed light on the linkage between vegetation acclimation under climate change and microtopography variability controls on ecohydrologic processes. [ABSTRACT FROM AUTHOR]

Correction to: I Nature Communications i https://doi.org/10.1038/s41467-023-39463-9, published online 28 June 2023 The original version of this Article contained an error in Fig. Instead, they were meant to show the percentage of land surface area with NSE above a given threshold ("Land surface area (%)") as described in the title and caption of the Figure. 1, in which the vertical axes in all panels showed the cumulative distribution function ("CDF"), i.e., the fraction of land surface area with Nash-Sutcliffe Efficiency (NSE) below a given threshold. [Extracted from the article]