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Atlantic multidecadal variability (AMV) is a cornerstone for decadal prediction and profoundly influences regional and global climate variability, yet its fundamental drivers remain an issue for debate. Studies suggest that external forcing may have affected AMV during the Little Ice Age (AD 1400–1860). However, the detailed mechanism remains elusive, and the AMV’s centennial to millennial variations over the past 2000 years have not yet been explored. We first show that proxy-data reconstructions and paleo-data assimilations suggest a significant 60-yr AMV during AD 1250–1860 but not during AD 1–1249. We then conducted a suite of experiments with the Community Earth System Model (CESM) to unravel the causes of the changing AMV property. The simulation results under all external forcings match the reconstructions reasonably well. We find that the significant 60-yr AMV during 1250–1860 arises predominantly from the volcano forcing variability. During the period 1–1249, the average volcanic eruption intensity is about half of the 1250–1860 intensity, and a 20–40-yr internal variability dominates the AMV. The volcanic radiative forcing during 1250–1860 amplifies AMV and shifts the internal variability peak from 20–40 years to 60 years. The volcano forcing prolongs AMV periodicity by sustaining Arctic cooling, delaying subpolar sea ice melting and atmospheric feedback to reduce surface evaporation. These slow-response processes over the subpolar North Atlantic results in a persisting reduction of sea surface salinity, weakening the Atlantic overturning circulation, and warm water transport from the subtropical North Atlantic. The results reveal the cause of the nonstationary AMV over the past two millennia and shed light on the AMV’s response to external forcing. Significance Statement AMV plays an important role in the regional and global climate variability. The purpose of this study is to better understand the secular change of AMV during the past 2000 years and its response to the external forcing. Proxy data and model simulation consistently show a significant 60-yr AMV during AD 1250–1860 that is absent during AD 1–1249. Active volcanic eruptions during 1250–1860 amplify the AMV and shift its intrinsic 20–40-yr to a prominent 60-yr variance peak. Volcanoes prolong AMV periodicity by sustaining Arctic cooling, delaying subpolar sea ice melting, reducing evaporation, and increasing surface salinity. These results help us better understand nonstationary AMV and highlight the role of external forcing over the past two millennia.

The Malaysian government reinforced smoking restrictions at public venues to protect nonsmokers from secondhand smoke (SHS) exposure. This study examined whether smokers' reports about smoking restrictions and psychosocial beliefs were associated with quit intentions among Malaysian smokers. Data from 1047 cigarette smokers (103 females and 944 males) aged 18 and older from the 2020 International Tobacco Control (ITC) Malaysia Wave 1 Survey were analyzed with bivariate and multivariable logistic regression models. Most Malaysian smokers (85.2%) reported having quit intentions. Smoking was completely restricted in 34.8% of the nighttime venues, 85.3% of air-conditioned (AC) food and beverage (FB) venues (restaurants, food courts, coffee shops), 87.3% of non-AC FB, and 69.4% of indoor workplaces. Smokers who visited nighttime entertainment venues where smoking was fully restricted were less likely to have quit intentions. There was no significant association found with quit intentions for smokers who visited AC and non-AC FB venues and indoor workplaces where smoking was fully restricted. All five psychosocial beliefs assessed, age, and education were positively associated with quit intentions. Malaysian smokers are interested in quitting and psychosocial beliefs were positively associated with quit intentions. There is a need for the Malaysian government to implement and reinforce comprehensive smoking restrictions in all public venues and indoor workplaces to protect nonsmokers from SHS exposure and to encourage smokers to think about quitting, which may influence their quit intentions.

In 1970, the Southern Corn Leaf Blight epidemic ravaged US fields to great economic loss. The outbreak was caused by never-before-seen, super-virulent, Race T of the fungusCochliobolus heterostrophus. The functional difference between Race T and O, the previously known, far less aggressive strain, is production of T-toxin, a host-selective polyketide. Super-virulence is associated with ∼1 Mb of Race T- specific DNA; only a fraction encodes T-toxin biosynthetic genes (Tox1).Tox1is genetically and physically complex, with unlinked loci (Tox1A, Tox1B) genetically inseparable from breakpoints of a Race O reciprocal translocation that generated hybrid Race T chromosomes. Previously, we identified ten genes for T-toxin biosynthesis. Unfortunately, high depth, short-read sequencing placed these genes on four small, unconnected scaffolds surrounded by repeated A+T rich sequence, concealing context. To sort outTox1topology and pinpoint the hypothetical Race O translocation breakpoints corresponding to Race T-specific insertions, we undertook PacBio long-read sequencing which revealedTox1gene arrangement and the breakpoints. SixTox1Agenes are arranged as three small islands in a Race T-specific sea (∼634 kb) of repeats. FourTox1Bgenes are linked, on a large loop of Race T-specific DNA (∼210 kb). The race O breakpoints are short sequences of race O-specific DNA; corresponding positions in race T are large insertions of race T-specific, A+T rich DNA, often with similarity to transposable (predominantly Gypsy) elements. Nearby, are ‘Voyager Starship’ elements and DUF proteins. These elements may have facilitatedTox1integration into progenitor Race O and promoted large scale recombination resulting in race T.ImportanceIn 1970 a corn disease epidemic ravaged fields in the US to great economic loss. The outbreak was caused by a never-before seen, super-virulent strain of the fungal pathogenCochliobolus heterostrophus. This was a plant disease epidemic, however, the current COVID-19 pandemic of humans is a stark reminder that novel, highly virulent, pathogens evolve with devastating consequences, no matter what the host-animal, plant, or other organism. Long read DNA sequencing technology allowed in depth structural comparisons between the sole, previously known, much less aggressive, version of the pathogen and the super-virulent version and revealed, in meticulous detail, the structure of the unique virulence-causing DNA. These data are foundational for future analysis of mechanisms of DNA acquisition from a foreign source.

High-frequency soft magnetic ferrite ceramics are desired in miniaturized and efficient power electronics but remain extremely challenging to deploy on account of the power loss (Pcv) at megahertz frequencies. Here, we prepared NiCuZn ferrite with superior high-frequency properties by V2O5 and Bi2O3 synergistic doping, which proves to be a potent pathway to reduce Pcv of the ferrite at megahertz frequencies. The sample doped with 800 ppm V2O5 and 800 ppm Bi2O3 yielded the most optimized magnetic properties with a Pcv of 113 kW/m3 (10 MHz, 5 mT, 25 °C), an initial permeability (μi) of 89, and a saturation induction (Bs) of 340 mT, which is at the forefront of the reported results. These outstanding properties are closely related to the notable grain boundary structure, which features a new type of nano-Bi2Fe4O9 phase around ferrite grains and a Ca/Si/V/O amorphous layer. Our results indicate great strides in correlating the grain boundary structure with multiple-ion doping and set the scene for the developing high-frequency soft magnet ferrites.

Usually the improved coercivity of rare earth (RE) based 2:14:1-type permanent magnets via RE-rich intergranular additives is achieved at the cost of more corrosion channels and deteriorated corrosion resistance, which remains a challenging hurdle in the RE-Fe-B community. Distinctly, here we report the concurrent improvements of corrosion resistance and coercivity in 40 wt.% Ce-substituted Nd-Ce-Fe-B sintered magnets through engineering the intergranular phase using simple (Nd, Pr)Hx additive. The dehydrogenated Nd/Pr changes the RE concentration gradients between 2:14:1 matrix and intergranular phases during sintering and enlarges the fraction of corrosion-resistant REFe2 phase, rather than the conventionally assumed Nd/Pr-rich intergranular phase with high chemical vulnerability. The spontaneous formation of REFe2 intergranular phase after (Nd, Pr)Hx addition generates the uniquely enhanced corrosion resistance against the hot/humid and acidic environments, and counts as one peculiar feature of Nd-Ce-Fe-B magnets at high Ce substitution level, being distinct from previously reported Ce-free/lean RE-Fe-B. Simultaneously, the formation of continuous grain boundaries enhances the coercivity from 8.7 to 12.5 kOe with trace addition of (Nd, Pr)Hx. Above findings may spur progress towards developing a high-performance Nd-Ce-Fe-B permanent magnet.

Introduction Mushroom-forming fungi comprise diverse species that develop complex multicellular structures. In cultivated species, both ecological adaptation and artificial selection have driven genome evolution. However, little is known about the connections among genotype, phenotype and adaptation in mushroom-forming fungi. Objectives This study aimed to (1) uncover the population structure and demographic history of Lentinula edodes, (2) dissect the genetic basis of adaptive evolution in L. edodes, and (3) determine if genes related to fruiting body development are involved in adaptive evolution. Methods We analyzed genomes and fruiting body-related traits (FBRTs) in 133 L. edodes strains and conducted RNA-seq analysis of fruiting body development in the YS69 strain. Combined methods of genomic scan for divergence, genome-wide association studies (GWAS), and RNA-seq were used to dissect the genetic basis of adaptive evolution. Results We detected three distinct subgroups of L. edodes via single nucleotide polymorphisms, which showed robust phenotypic and temperature response differentiation and correlation with geographical distribution. Demographic history inference suggests that the subgroups diverged 36,871 generations ago. Moreover, L. edodes cultivars in China may have originated from the vicinity of Northeast China. A total of 942 genes were found to be related to genetic divergence by genomic scan, and 719 genes were identified to be candidates underlying FBRTs by GWAS. Integrating results of genomic scan and GWAS, 80 genes were detected to be related to phenotypic differentiation. A total of 364 genes related to fruiting body development were involved in genetic divergence and phenotypic differentiation. Conclusion Adaptation to the local environment, especially temperature, triggered genetic divergence and phenotypic differentiation of L. edodes. A general model for genetic divergence and phenotypic differentiation during adaptive evolution in L. edodes, which involves in signal perception and transduction, transcriptional regulation, and fruiting body morphogenesis, was also integrated here.

Shrub willows (Salix spp.) are emerging as a viable lignocellulosic, second-generation bioenergy crop with many growth characteristics favorable for marginal lands in New York State and surrounding areas. Willow rust, caused by members of the genus Melampsora, is the most limiting disease of shrub willow in this region and remains extremely understudied. In this study, genetic diversity, genetic structure, and pathogen clonality were examined in Melampsora americana over two growing seasons via genotyping-by-sequencing to identify single-nucleotide polymorphism markers. In conjunction with this project, a reference genome of rust isolate R15-033-03 was generated to aid in variant discovery. Sampling between years allowed regional and site-specific investigation into population dynamics, in the context of both wild and cultivated hosts within high-density plantings. This work revealed that this pathogen is largely panmictic over the sampled areas, with few sites showing moderate genetic differentiation. These data support the hypothesis of sexual recombination between growing seasons because no genotype persisted across the two years of sampling. Additionally, clonality was determined as a driver of pathogen populations within cultivated fields and single shrubs; however, there is also evidence of high genetic diversity of rust isolates in all settings. This work provides a framework for M. americana population structure in the Great Lakes region, providing crucial information that can aid in future resistance breeding efforts.

Fungi have evolved over millions of years and their species diversity is predicted to be the second largest on the earth. Fungi have cross-kingdom interactions with many organisms that have mutually shaped their evolutionary trajectories. Zygomycete fungi hold a pivotal position in the fungal tree of life and provide important perspectives on the early evolution of fungi from aquatic to terrestrial environments. Phylogenomic analyses have found that zygomycete fungi diversified into two separate clades, the Mucoromycota which are frequently associated with plants and Zoopagomycota that are commonly animal-associated fungi. Genetic elements that contributed to the fitness and divergence of these lineages may have been shaped by the varied interactions these fungi have had with plants, animals, bacteria, and other microbes. To investigate this, we performed comparative genomic analyses of the two clades of zygomycetes in the context of Kingdom Fungi, benefiting from our generation of a new collection of zygomycete genomes, including nine produced for this study. We identified lineage-specific genomic content that may contribute to the disparate biology observed in these zygomycetes. Our findings include the discovery of undescribed diversity in CotH, a Mucormycosis pathogenicity factor, which was found in a broad set of zygomycetes. Reconciliation analysis identified multiple duplication events and an expansion of CotH copies throughout the Mucoromycotina, Mortierellomycotina, Neocallimastigomycota, and Basidiobolus lineages. A kingdom-level phylogenomic analysis also identified new evolutionary relationships within the subphyla of Mucoromycota and Zoopagomycota, including supporting the sister-clade relationship between Glomeromycotina and Mortierellomycotina and the placement of Basidiobolus as sister to other Zoopagomycota lineages.

Seagrasses comprise the only submerged marine angiosperms, a feat of adaptation from three independent freshwater lineages within the Alismatales. These three parallel lineages offer the unique opportunity to study convergent versus lineage-specific adaptation to a fully marine lifestyle. Here, we present chromosome-level genome assemblies from a representative species of each of the seagrass lineages -Posidonia oceanica(Posidoniaceae),Cymodocea nodosa(Cymodoceaceae), andThalassia testudinum(Hydrocharitaceae)-along with an improved assembly forZostera marina(Zosteraceae). We also include a draft genome ofPotamogeton acutifolius, a representative of Potamogetonaceae, the freshwater sister lineage to the Zosteraceae. Genome analysis reveals that all seagrasses share an ancient whole genome triplication (WGT) event, dating to the early evolution of the Alismatales. An additional whole genome duplication (WGD) event was uncovered forC. nodosaandP. acutifolius. Dating of ancient WGDs and more recent bursts of transposable elements correlate well with major geological and recent climatic events, supporting their role as rapid generators of genetic variation. Comparative analysis of selected gene families suggests that the transition from the submerged-freshwater to submerged-marine environment did not require revolutionary changes. Major gene losses related to, e.g., stomata, volatiles, defense, and lignification, are likely a consequence of the submerged lifestyle rather than the cause (‘use it or lose it’). Likewise, genes, often retained from the WGD and WGT, were co-opted for functions requiring the alignment of many small adaptations (‘tweaking’), e.g., osmoregulation, salinity, light capture, carbon acquisition, and temperature. Our ability to manage and conserve seagrass ecosystems depends on our understanding of the fundamental processes underpinning their resilience. These new genomes will accelerate functional studies and are expected to contribute to transformative solutions — as continuing worldwide losses of the ‘savannas of the sea’ are of major concern in times of climate change and loss of biodiversity.

Solar activity affects Asian summer monsoon (ASM) at various time scales. However, it remains unknown if and how solar activity can influence ASM on the centennial time scale. Using the Community Earth System Model, we conduct a solar activity forced Holocene transient simulation with an acceleration factor of 10 and show that during the middle‒late Holocene ASM precipitation exhibits a significant 300‒600-year periodicity under solar forcing. This model-produced multi-centennial variation is also suggested by proxy data. The leading mode of the multi-centennial ASM variation shows a “wet tropics–dry subtropics” pattern, which lags the corresponding solar activity by about a quarter cycle. The western North Pacific (WNP) circulation system is responsible for the multi-centennial ASM variation, through enhancing the climatological south Asia‒WNP monsoon trough. We suggest that solar activity modulates the zonal SST gradients of the tropical Pacific, inducing the anomalous WNP cyclone and enhancing ASM precipitation in a delayed mode.

The Asian-Australian monsoon system is mainly composed of East Asian monsoon, Australian monsoon and South Asian monsoon. The Australian monsoon and East Asian monsoon can form the East Asian-Australian monsoon system through the cross-equatorial flow over Maritime Continent and the atmospheric lateral coupling. On the other hand, the East Asian monsoon and the Australian monsoon can be relatively independent regional climate systems due to the difference of land-sea configuration and the influence of tropical ocean. Therefore, under different forcings, the evolutionary relationship between the two may be different on different time scales. In this study, we investigated the evolutionary relationship between East Asian winter monsoon (EAWM) and Australian summer monsoon (AUSM) at orbital scales, utilizing a set of transient simulations over past 300,000 years conducted with NCAR-CCSM3. It is found that, the variations of EAWM and AUSM are significantly in-phase at obliquity scale. In the case of high obliquity, when the northern Hemisphere (NH) is winter/the southern Hemisphere (SH) is summer, the NH receives less insolation while the SH receives more, leading to both intensified EAWM and AUSM. Meanwhile, the cross-equatorial flow is also enhanced due to the strengthened hemispheric insolation gradient, which "consolidates" the positive relationship between EAWM and AUSM. Whereas at precession scale, EAWM and AUSM show out-of-phase relationship. Taking low precession for instance, when the summer solstice of the NH is located at perihelion, the insolation over NH and SH both decrease in boreal winter/southern summer, leading to strengthened EAWM. AUSM, however, is weakened due to the reduced insolation. This may be because the AUSM is mainly controlled by local insolation. That is, the reduction of local insolation directly leads to the weakening of the AUSM, and “cut off” the link between EAWM and AUSM. The above results are based on the monsoon index defined by the wind field. We also notice that the East Asian summer monsoon precipitation and the Australian summer monsoon precipitation show significant out-of-phase relationship at precession scale, while in-phase relationship at obliquity scale, which could be well explained by the seasonal variation of insolation caused by the change of precession and obliquity. The different relationship between EAWM and AUSM at precession and obliquity scales is robust in pure orbital run and three forcings run, which is forced by orbital parameters, greenhouse gases and icesheet.

The 4.2 ka BP event is one of the most severe centennial-scale cold and megadrought events during the Holocene, with serious influences on the collapse of the Akkadian Empire, and many other old civilizations. Based on 173 proxy records across the global monsoon regions and isotope-enabled Community Earth System Model last millennium ensemble (CESM-iLME), a group of precipitation 18O reanalysis for the period 2 ka-5 ka BP were reconstructed through the hybrid gain analog offline ensemble Kalman filter (HG-AOEnKF) with the fast implementation framework of Last Millennium Reanalysis (LMR) paleoclimate data assimilation. The time series showed that the 4.2 ka BP event in all northern Hemisphere monsoon regions exhibits as monsoon weakening, but are not synchronous. Spatially, consistent with the proxy data, during the 4.2 ka BP event, the East Asian summer monsoon shows wet anomalies in the south and drought anomalies in the north, and the North African monsoon, South Asian summer monsoon, and North American monsoon show unified drought anomalies. While, all three southern Hemisphere monsoon, i.e., South American monsoon, Australian monsoon, South African monsoon, show wet anomalies during the 4.2 ka BP event. Based on model simulations, it is found that the potential mechanism behind the 4.2ka BP event is the multi-century-scale fluctuations in SSTs across the North Atlantic and AMOC strength, superimposed on the steady decline in SSTs and AMOC led by long-term changes of orbital forcing.

A facile oxidation strategy is proposed to in situ grow a hydrophobic, thin and uniform triplex surface coating on Nd–Fe–B, which ensures outstanding anti-corrosion performance, accompanied with synergistic magnetic and mechanical performance.

E-cigarettes (ECs) have become increasingly common in many countries, including Malaysia. The prevalence of EC use increased in Malaysia from 0.8% in 2011 to 4.9% in 2019. Three quarters of Malaysian EC users also smoke combustible cigarettes, and the prevalence of EC use among Malaysian smokers in 2014 was consistent with the prevalence of use among smokers from Canada and the US in 2016. The purpose of this study was to estimate the prevalence of EC use among Malaysian adults aged ≥18 years in 2020 and the types of EC products and flavors used by cigarette smokers who also used ECs at least monthly.Data came from 1253 adults aged ≥18 years who participated in the 2020 International Tobacco Control Malaysia Wave 1 Survey. Weighted descriptive statistics were used to estimate the prevalence of adults who reported ever using ECs and the prevalence who used ECs either monthly, weekly, or daily. The types of EC products and flavors used were compared by frequency of EC use among current smokers who used ECs at least monthly (n=459).Overall, 5.4% (95% CI: 3.7-7.5) of Malaysian adults reported using ECs on a daily basis in 2020. Among current cigarette smokers who used ECs daily, 81.0% (95% CI: 72.5-87.7) used nicotine in their ECs, 46.2% (95% CI: 37.8-54.7) used pre-filled ECs, and 60.4% (95% CI: 51.9-68.6) reported being somewhat/very addicted to ECs. The most common EC flavors were fruit, coffee, and menthol/ mint.Continued surveillance of EC use is necessary to monitor EC use in non-tobacco using populations while longitudinal research is needed to determine the extent to which ECs are, or are not, related to quitting smoking.

This article presents methods used in the 2020 International TC Korea Wave 1 (KRA1) Survey. To date, three cohorts of Korean respondents have participated in the larger ITC Korea Project (cohort 1: 2005-2014, cohort 2: 2016, and cohort 3: 2020-present). The overall objectives of the ITC KRA1 Survey were to examine the use of cigarettes, heated tobacco products (HTPs), e-cigarettes (ECs); whether HTPs might help smokers quit; and the effectiveness of tobacco control policies, such as large graphic warnings, high cigarette taxes, and smoking bans in public places. The KRA1 Survey measures were identical or functionally similar to those of the ITC Japan Survey and, to a lesser extent, those of other ITC countries. Key measures assessed sociodemographic characteristics of respondents; the use of combustible cigarettes, e-cigarettes, and heated tobacco products; and measures assessing policies of the WHO Framework Convention on Tobacco Control, including price and tax (Article 6), smoke-free laws (Article 8), health warnings (Article 11), education, communication and public awareness (Article 12), advertising, promotion, and sponsorship restrictions (Article 13), and support for cessation (Article 14). Adult tobacco and/or nicotine users aged ≥19 years in South Korea were recruited by a commercial survey firm from its online panel. Overall, 4794 respondents completed the KRA1 Survey. The cooperation rate was 97.4% and the response rate was 15.2%. The cohort design permits assessment of transitions in products used among users in South Korea and evaluations of the impact of policies on tobacco and/or nicotine products used and transitions in use.