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Since their advent over 2 decades ago, autonomous Argo floats have revolutionized the field of oceanography, and, more recently, the addition of biogeochemical and biological sensors to these floats has greatly improved our understanding of carbon, nutrient, and oxygen cycling in the ocean. While Argo floats offer unprecedented horizontal, vertical, and temporal coverage of the global ocean, uncertainties remain about whether Argo sampling frequency and density capture the true spatiotemporal variability in physical, biogeochemical, and biological properties. As the true distributions of, e.g., temperature or oxygen are unknown, these uncertainties remain difficult to address with Argo floats alone. Numerical models with synthetic observing systems offer one potential avenue to address these uncertainties. Here, we implement synthetic biogeochemical Argo floats into the Energy Exascale Earth System Model version 2 (E3SMv2), which build on the Lagrangian In Situ Global High-Performance Particle Tracking (LIGHT) module in E3SMv2 (E3SMv2-LIGHT-bgcArgo-1.0). Since the synthetic floats sample the model fields at model run time, the end user defines the sampling protocol ahead of any model simulation, including the number and distribution of synthetic floats to be deployed, their sampling frequency, and the prognostic or diagnostic model fields to be sampled. Using a 6-year proof-of-concept simulation, we illustrate the utility of the synthetic floats in different case studies. In particular, we quantify the impact of (i) sampling density on the float-derived detection of deep-ocean change in temperature or oxygen and on float-derived estimates of phytoplankton phenology, (ii) sampling frequency and sea-ice cover on float trajectory lengths and hence float-derived estimates of current velocities, and (iii) short-term variability in ecosystem stressors on estimates of their seasonal variability. [ABSTRACT FROM AUTHOR]

Simple Summary: In addition to invaluable ecosystem services, beekeeping offers opportunities for job creation, income generation and food security. Beekeepers have been experiencing economic losses due to high rates of honey bee colony losses driven by various factors worldwide. We conducted this study using the COLOSS monitoring survey tools for the first time in Ethiopia to assess honey bee colony loss rates, annual colony development, beekeeping practices, and to determine the role of management practices (varroa monitoring, varroa treatment, colony splitting, feed supplementation, use of natural comb, and purchase of beeswax from external sources), as well as region, on colony losses. For this, data were collected by interviewing beekeepers from two major beekeeping regions in the country—Oromia and Tigray. Our results showed a high rate of colony losses in Ethiopia, which significantly varied between the regions. The main drivers of honey bee colony losses are related to natural disasters (particularly war), beekeeping husbandry practices, and pest management. Therefore, it is important to promote the capacity of smallholder beekeepers to implement improved beekeeping practices such as feed supplementation, queen replacement and pest management that would lead to reduced losses, increased profitability, and improved food security and livelihood. The COLOSS research association has been assessing honey bee colony losses, associated risk factors and management, focusing on Western countries but with a progressive international expansion. Here, we report the first survey on the loss rates of colonies in 2022/2023 in Ethiopia using COLOSS monitoring survey tools. A face-to-face interview questionnaire survey was conducted on 64 beekeepers selected from Oromia and Tigray regions. This covered 1713 honey bee colonies distributed in 68 apiaries. The percentages of colonies lost were significantly different between Oromia (24.1%) and Tigray (66.4%) regions. Colony losses were attributed as unsolvable queen problems (8% in Oromia; 10% in Tigray), natural disaster (32%; 82%), and empty hives or dead colonies (60%; 8%). The loss rate was significantly affected by queen replacement (p < 0.0001), use of natural comb (p < 0.0001), feed supplementation (p < 0.0001), region (p < 0.0001), varroa treatment (p < 0.0001), colony splitting (p < 0.01), and merging (p < 0.01). Beekeepers in Oromia managed more colonies and implemented improved practices compared to those in Tigray. However, all beekeepers in Oromia detected at least some bees with signs of deformed wing virus, compared to 76% of beekeepers in Tigray. In conclusion, the colony loss rate was significantly different between Oromia and Tigray regions due to differences in natural disasters, management, environment and health factors. [ABSTRACT FROM AUTHOR]

Kilovoltage therapy units are used for superficial radiotherapy treatment delivery. Peer reviewed studies for MV linear accelerators describe tolerances to dosimetrically match multiple linear accelerators enabling patient treatment on any matched machine. There is an absence of literature on using a single planning data set for multiple kilovoltage units which have limited ability for beam adjustment. This study reviewed kilovoltage dosimetry and treatment planning scenarios to evaluate the feasibility of using ACPSEM annual QA tolerances to determine whether two units (of the same make and model) were dosimetrically matched. The dosimetric characteristics, such as measured half value layer (HVL), percentage depth dose (PDD), applicator factor and output variation with stand-off distance for each kV unit were compared to assess the agreement. Independent planning data based on the measured HVL for each beam energy from each kV unit was prepared. Monitor unit (MU) calculations were performed using both sets of planning data for approximately 200 clinical scenarios and compared with an overall agreement between units of < 2%. Additionally, a dosimetry measurement comparison was completed at each site for a subset of nine scenarios. All machine characterisation measurements were within the ACPSEM Annual QA tolerances, and dosimetric testing was within 2.5%. This work demonstrates that using a single set of planning data for two kilovoltage units is feasible, resulting in a clinical impact within published uncertainty. [ABSTRACT FROM AUTHOR]

The document is a compilation of scientific articles and reports related to oceanography and climate research. The articles cover a wide range of topics including phytoplankton bloom phenology, ocean currents, carbon cycle simulations, sea-ice dynamics, and subsurface chlorophyll concentrations. These articles provide valuable information for researchers studying these specific topics and highlight the importance of ongoing research and monitoring efforts in understanding and predicting changes in the marine environment. [Extracted from the article]

Global estimates of mesoscale vertical velocity remain poorly constrained due to a historical lack of adequate observations on the spatial and temporal scales needed to measure these small magnitude velocities. However, with the wide‐spread and frequent observations collected by the Argo array of autonomous profiling floats, we can now better quantify mesoscale vertical velocities throughout the global ocean. We use the underutilized trajectory data files from the Argo array to estimate the time evolution of isotherm displacement around a float as it drifts at 1,000 m, allowing us to quantify vertical velocity averaged over approximately 4.5 days for that depth level. The resulting estimates have a non‐normal, high‐peak, and heavy‐tail distribution. The vertical velocity distribution has a mean value of (1.9 ± 0.02) × 10−6 m s−1 and a median value of (1.3 ± 0.2) × 10−7 m s−1, but the high‐magnitude events can be up to the order of 10−4 m s−1. We find that vertical velocity is highly spatially variable and is largely associated with a combination of topographic features and horizontal flow. These are some of the first observational estimates of mesoscale vertical velocity to be taken across such large swaths of the ocean without assumptions of uniformity or reliance on horizontal divergence. Plain Language Summary: Vertical velocity in the ocean is a fundamental part of how water circulates throughout the globe. This impacts the temperature, salt, nutrients, and currents that make up the ocean. However, vertical velocities are very small and are, therefore, difficult to measure. In particular, the vertical velocities of ocean events that occur on roughly a weekly to monthly time scale (mesoscale) are poorly understood. We have developed a method for estimating these mesoscale vertical velocities across the globe using an array of autonomous robots called Argo floats. Our results show that vertical velocities vary greatly depending on location, with the largest values occurring where there is a combination of relatively shallow ocean depths and larger horizontal velocities. These estimates are some of the first of their kind to be made from observations across such large swaths of the ocean. Key Points: Five‐day averaged vertical velocities from Argo observations near 1,000 m are non‐normally distributed, with a high peak and heavy tailsMesoscale vertical velocities are on the order of centimeters per day, but high‐magnitude events can be on the order of meters per dayVertical velocities estimated from Argo floats are spatially variable and correlated with topographic features and horizontal surface flow [ABSTRACT FROM AUTHOR]

Oceanic macroturbulence is efficient at stirring and transporting tracers. The dynamical properties of this stirring can be characterized by statistically quantifying tracer structures. Here, we characterize the macroscale (1–100 km) tracer structures observed by two Seagliders downstream of the Southwest Indian Ridge in the Antarctic Circumpolar Current (ACC). These are some of the first glider observations in an energetic standing meander of the ACC, a region associated with enhanced ventilation. The small‐scale density variance in the mixed layer (ML) was relatively enhanced near the surface and base of the ML, while being muted at mid‐depth in the ML, suggesting the formation mechanism to be associated with ML instabilities and eddies. In addition, ML density fronts were formed by comparable contributions from temperature and salinity gradients. In the interior, along‐isopycnal spectra and structure functions of spice indicated that there is relatively lower variance at smaller scales than would be expected based on non‐local stirring, suggesting that flows smaller than the deformation radius play a role in the cascade of tracers to small scales. These interior spice anomalies spanned across isopycnals, and were found to be about 3–5 times flatter than the aspect ratio that would be expected for O(1) Burger number flows like interior QG dynamics, suggesting the ratio of vertical shear to horizontal strain is greater than N/f. This further supports that small‐scale flows, with high‐mode vertical structures, impact tracer distributions. Plain Language Summary: Ocean eddies and fronts are efficient at stirring and generating tracer structures spanning a wide range of scales. This stirring is important for uptake of tracers, particularly in the Southern Ocean where sloping density surfaces provide a direct pathway from the surface into the interior. While the qualitative nature of stirring seems clear, quantitatively characterizing properties of this stirring is necessary to build accurate parameterizations and understand how the ocean is ventilated. One way to characterize this is by quantifying the distribution of the tracer concentration as a function of scale. Here, we do this characterization by analyzing data collected by two gliders in a region where the mean current of the Southern Ocean meanders as it flows over topography, and is likely to be a hot spot for ventilation. This analysis reveals that relatively small eddies generated by a process known as mixed layer instability are active in the mixed layer and play an important role in setting the near‐surface stratification. Surprisingly, tracer structure below the mixed layer also indicates that flows with small horizontal and vertical scales play a role in stirring. This challenges conventional wisdom, which assumes that only the largest eddies are important for stirring. Key Points: Glider observations were used to analyze tracer structure at scales ≤100 km in the Antarctic Circumpolar CurrentThe vertical structure of density variance in the mixed layer (ML) is suggestive of ML instabilities and eddiesSmall‐scale flows contribute to stirring in the interior, as indicated by passive tracer structure [ABSTRACT FROM AUTHOR]

Despite its importance for the global cycling of carbon, there are still large gaps in our understanding of the processes driving annual and seasonal carbon fluxes in the high‐latitude Southern Ocean. This is due in part to a historical paucity of observations in this remote, turbulent, and seasonally ice‐covered region. Here, we use autonomous biogeochemical float data spanning 6 full seasonal cycles and with circumpolar coverage of the Southern Ocean, complemented by atmospheric reanalysis, to construct a monthly climatology of the mixed layer budget of dissolved inorganic carbon (DIC). We investigate the processes that determine the annual mean and seasonal cycle of DIC fluxes in two different zones of the Southern Ocean—the Sea Ice Zone (SIZ) and Antarctic Southern Zone (ASZ). We find that, annually, mixing with carbon‐rich waters at the base of the mixed layer supplies DIC which is, in the ASZ, either used for net biological production or outgassed to the atmosphere. In contrast, in the SIZ, where carbon outgassing and the biological pump are weaker, the surplus of DIC is instead advected northward to the ASZ. In other words, carbon outgassing in the southern Antarctic Circumpolar Current (ACC), which has been attributed to remineralized carbon from deep water upwelled in the ACC, is also due to the wind‐driven transport of DIC from the SIZ. These results stem from the first observation‐based carbon budget of the circumpolar Southern Ocean and thus provide a useful benchmark to evaluate climate models, which have significant biases in this region. Plain Language Summary: The ocean surrounding the frozen continent of Antarctica plays an important role in the global cycling of carbon and is important for the climate of our planet. Despite its importance, there are gaps in our knowledge due to the difficulties involved in collecting data from a remote, seasonally ice‐covered ocean. In this study, we use year‐round data collected by autonomous instruments that can even measure under sea ice. We build a budget of carbon in the surface layer of the ocean, quantifying the different sources and sinks of inorganic carbon. We find that carbon mostly enters the surface layer through mixing with carbon‐rich waters below. In the more stormy, northern part of our study area, this carbon is then either consumed by photosynthesis in the ocean or it is transferred to the atmosphere. In the southernmost region, biological activity and gas transfer at the ocean‐atmosphere interface is hindered by the presence of sea ice and the surplus of carbon is instead transferred north by wind‐driven circulation. Our results show that year‐round measurements of carbon are necessary to understand carbon cycling in the region and we provide a useful product to compare to global simulations of the Earth system. Key Points: We build a Southern Ocean observation‐based mixed layer inorganic carbon budget with circumpolar coverage and a full seasonal cycleBiological activity and circulation dominate the seasonal variations in mixed layer dissolved inorganic carbonWind‐driven transport from the seasonal ice zone contributes to carbon outgassing in the Antarctic Circumpolar Current [ABSTRACT FROM AUTHOR]

This paper surveys flood mapping and modelling in Nigeria in regard to frequency and impact of floods in the last decade. The aim is to understand the frequency and patterns of flooding and approaches to its modelling in relation to current practices globally. The northern part of Nigeria is affected more by flooding than the south, so should be prioritised for flood management. The use of remote sensing data with GIS techniques is the most common approach to flood modelling in Nigeria. Bayesian and machine learning approaches should be used, in preference to process-based models. [ABSTRACT FROM AUTHOR]

Simple Summary: Relatively little is known about experience of beekeepers, honey bee management practices and colony loss rates in Saudi Arabia and the Middle East compared to other countries, yet beekeeping and honey production are important in the Saudi economy. Results of a survey of 109 beekeepers in Saudi Arabia conducted in 2018 are presented, from a purpose-designed questionnaire, including colony losses over 5 seasons, to help fill this knowledge gap. The participants were managing 135 to 1700 colonies and had 2 to 45 years of beekeeping experience. Most (73.1%) respondents were mainly keeping local hybrid bees, while 25.9% mainly kept the Yemeni honey bee. Most (83.5%) beekeepers reported losing colonies over the time period studied. The reported colony loss rate was significantly higher in summer than in other seasons: the overall proportion of colonies lost was 11.4% in summer 2017 and was lowest in spring 2018 (6.6%). The main reported causes of colony losses were the Varroa mite, then disease. However, the bee wolf was the major named pest. Honey produced per colony varied greatly between beekeepers rather than bee races. The results establish a benchmark for future beekeeper surveys in Saudi Arabia and other environmentally similar countries where colony losses are of interest in all seasons of the year. There is high demand for honey in Saudi Arabia, honey bees make a valuable contribution to agriculture and the economy, and therefore it is important to know levels of colony loss and potential reasons for losses. While there is much research into honey bee colony losses worldwide, little is known about colony losses in Saudi Arabia, management practices or beekeeping experience there. The aims of this work were to address this knowledge gap. Results of a survey of beekeepers in southwest Saudi Arabia conducted in summer 2018 are presented, including colony losses in five different seasons. Data collection involved face-to-face interviews, supplemented by an online survey, using a purpose-designed questionnaire. Responses were obtained from 109 beekeepers, all male, managing 135 to 1700 colonies, with 2 to 45 years of beekeeping experience. Most (73.1%) respondents mainly kept local hybrid bees, while 25.9% mainly kept Apis mellifera jemenitica. Honey yields per colony varied much more between beekeepers than between bee races. A high proportion (83.5%) of beekeepers reported losing colonies over the period studied. The reported colony loss rate was significantly higher in summer than in other seasons, but still low. The overall proportion of colonies lost was 11.4% in summer 2017 and was lowest in spring 2018 (6.6%). The main reported causes of loss were Varroa destructor and disease. Most beekeepers (88.0%) treated against the Varroa mite, although only one method was reported, tau-fluvalinate as Apistan strips, and only 41.7% used a screened bottom board. The results establish a benchmark for future beekeeper surveys in Saudi Arabia and other environmentally similar countries where colony losses are of interest in all seasons of the year. Informing and supporting Saudi beekeepers concerning Varroa monitoring and treatment and optimal hive management could result in fewer losses, higher honey yields, potential to market organic honey and a greater share of the domestic honey market. [ABSTRACT FROM AUTHOR]

Simple Summary: Honey bees (Apis mellifera) are important pollinators that benefit environmental conservation and agricultural production. Additionally, beekeeping is an important economic activity that currently faces the problem of high colony loss rates, particularly during winter. Finding solutions involves knowing the factors associated with high loss rates. To investigate whether loss rates are related to hive migration, beekeeping operation size, and Varroa control, we surveyed beekeepers from five states in Mexico after six consecutive winters (2016–2017 to 2021–2022). The results show an average colony loss rate of 22%, but these range from 14.9% to 30% between the years. The migration practice and beekeeping operation size did not influence the losses; however, Varroa control reduced colony losses. The main causes were problems related to the queen and dead colonies or empty hives, which showed differences between the winters analyzed. The results reveal high loss rates in the studied region, as has been reported in other countries. To improve the honey bee colony loss rates, it is suggested to improve the quality of queens, the control of varroasis and other diseases, and the degree of Africanization in order to reduce absconding. The objective of this study was to estimate the loss rates of honey bee (Apis mellifera) colonies in six consecutive winters (2016–2017 to 2021–2022) in five states of the semi-arid high plateau region of Mexico, as well as study the factors associated with these losses. The survey included data from 544 beekeepers and 75,341 colonies. The colony loss rate differs significantly (p < 0.0001) between the winters analyzed and fluctuates between 14.9% and 30%, with an average of 22%. Colony losses were unaffected (p > 0.05) by migratory beekeeping practice and operation size, but losses were significantly affected by Varroa monitoring and control (p ≤ 0.001). The types of loss differ among the winters analyzed. In the winters of 2016–2017 to 2018–2019, beekeepers attributed higher loss rates to unresolved problems related to the queen (e.g., a queenless colony, poor laying), but in the winters of 2019–2020 to 2021–2022, the highest loss rate was the result of problems such as diseases, poisoning, and absconding (leading to dead colonies or empty hives). The results reveal high loss rates in the region studied, as reported by beekeepers from other countries. It is suggested that strategies should be implemented to improve the quality of queens, the control of varroasis and other diseases, and the degree of Africanization. [ABSTRACT FROM AUTHOR]

Missing values in water level data is a persistent problem in data modelling and especially common in developing countries. Data imputation has received considerable research attention, to raise the quality of data in the study of extreme events such as flooding and droughts. This article evaluates single and multiple imputation methods used on monthly univariate and multivariate water level data from four water stations on the rivers Benue and Niger in Nigeria. The missing completely at random, missing at random and missing not at random data mechanisms were each considered. The best imputation method is identified using two error metrics: root mean square error and mean absolute percentage error. For the univariate case, the seasonal decomposition method is best for imputing missing values at various missingness levels for all three missing mechanisms, followed by Kalman smoothing, while random imputation is much poorer. For instance, for 5% missing data for the Kainji water station, missing completely at random, the Kalman smoothing, random and seasonal decomposition methods had average root mean square errors of 13.61, 102.60 and 10.46, respectively. For the multivariate case, missForest is best, closely followed by k nearest neighbour for the missing completely at random and missing at random mechanisms, and k nearest neighbour is best, followed by missForest, for the missing not at random mechanism. The random forest and predictive mean matching methods perform poorly in terms of the two metrics considered. For example, for 10% missing data missing completely at random for the Ibi water station, the average root mean square errors for random forest, k nearest neighbour, missForest and predictive mean matching were 22.51, 17.17, 14.60 and 25.98, respectively. The results indicate that the seasonal decomposition method, and missForest or k nearest neighbour methods, can impute univariate and multivariate water level missing data, respectively, with higher accuracy than the other methods considered. [ABSTRACT FROM AUTHOR]

This article presents managed honey bee colony loss rates over winter 2019/20 resulting from using the standardised COLOSS questionnaire in 37 countries. Six countries were from outside Europe, including, for the first time in this series of articles, New Zealand. The 30,491 beekeepers outside New Zealand reported 4.5% of colonies with unsolvable queen problems, 11.1% of colonies dead after winter and 2.6% lost through natural disaster. This gave an overall colony winter loss rate of 18.1%, higher than in the previous year. The winter loss rates varied greatly between countries, from 7.4% to 36.5%. 3216 beekeepers from New Zealand managing 297,345 colonies reported 10.5% losses for their 2019 winter (six months earlier than for other, Northern Hemisphere, countries). We modelled the risk of loss as a dead/empty colony or from unresolvable queen problems, for all countries except New Zealand. Overall, larger beekeeping operations with more than 50 colonies experienced significantly lower losses (p < 0.001). Migration was also highly significant (p < 0.001), with lower loss rates for operations migrating their colonies in the previous season. A higher proportion of new queens reduced the risk of colony winter loss (p < 0.001), suggesting that more queen replacement is better. All three factors, operation size, migration and proportion of young queens, were also included in a multivariable main effects quasi-binomial GLM and all three remained highly significant (p < 0.001). Detailed results for each country and overall are given in a table, and a map shows relative risks of winter loss at the regional level. [ABSTRACT FROM AUTHOR]

In recent years honey bee colonies have been seriously affected by colony losses, with implications for their future existence. Much has been written about beekeeping, honey bee management practices, and colony losses in many developed countries, but relatively little has been written about these topics in Saudi Arabia. This overview provides a brief insight into races of honey bees and beekeeping in Saudi Arabia. It also examines some important factors which have an impact on beekeeping within Saudi Arabia, including climatic factors and availability of forage. The main challenges faced by beekeepers in Saudi Arabia are discussed. Some conclusions are that honey is a much sought-after product in Saudi Arabia, and it is important for the economy to be able to meet this demand. As a result of the lucrativeness of the beekeeping industry, many have taken up beekeeping, but the industry lacks an overall structure, and lack of information and communication amongst beekeepers can mean that issues are not easily resolved. Hence, there is a need to gain more in-depth knowledge of beekeeping in Saudi Arabia, and in particular to identify common practices and challenges faced, so that trends, solutions, and best practices can be identified. Identification of aspects of beekeeping in Saudi Arabia which could be improved will be beneficial to all stakeholders involved in beekeeping there. [ABSTRACT FROM AUTHOR]

Flow‐topography interactions along the path of the Antarctic Circumpolar Current generate standing meanders, create regions of enhanced eddy kinetic energy (EKE), and modify frontal structure. We consider the impact of standing meanders on ventilation based on oxygen measurements from Argo floats and the patterns of apparent oxygen utilization (AOU). Regions of high‐EKE have relatively reduced AOU values at depths 200–700 m below the base of the mixed layer and larger AOU variance, suggesting enhanced ventilation due to both along‐isopycnal stirring and enhanced exchange across the base of the mixed layer. Vertical exchange is inferred from finite‐size Lyapunov exponents, a proxy for the magnitude of surface lateral density gradients, which suggest that submesoscale vertical velocities may contribute to ventilation. The shaping of ventilation by standing meanders has implications for the temporal and spatial variability of air‒sea exchange. Plain Language Summary: The circulation of the Southern Ocean is dominated by the eastward‐flowing Antarctic Circumpolar Current (ACC). The characteristics of the ACC are not uniform around the Southern Ocean. Rather, when the ACC encounters underwater mountain ranges the flow is diverted, which causes these regions to be more energetic through the generation of ocean eddies in a process similar to atmospheric storm tracks. Numerical models have suggested that the exchange of properties, such as heat and carbon dioxide, between the atmosphere and the interior ocean is enhanced in these energetic regions. In this study, data from freely floating robotic floats in the Southern Ocean is used to observe the vertical structure of dissolved oxygen. Transfer of properties between the ocean's surface and the interior ocean preferentially occurs in high energy regions of the ACC. Most previous work has relied on numerical models of the ocean that, due to computational limits, do not represent all aspects of the ACC's energetic regions. This study has implications for how the Southern Ocean's ability to take up excess carbon dioxide from the atmosphere will evolve in the future. Key Points: The relationship between apparent oxygen utilization (AOU) and eddy kinetic energy (EKE) is assessed in the Antarctic Circumpolar CurrentAOU has relatively reduced values below the mixed layer in high‐EKE standing meanders as compared to low‐EKE regionsModification of the density structure and enhanced meso‐ and submesoscale motions enhance ventilation in standing meanders [ABSTRACT FROM AUTHOR]

Phage display technology utilises peptide and antibody libraries with very high diversities to select ligands with specific binding properties. The production of such libraries can be labour intensive and technically challenging and whilst there are commercial sources of libraries, the exploitation of the resulting binders is constrained by ownership of the libraries. Here, a peptide library of ~ 1 × 109 variants for display on gene VIII was produced alongside three VHH antibody libraries with similar diversity, where 12mer, 16mer or 21mer CDR3s were introduced into the highly stable cAbBCII10 scaffold displayed on gene III. The cloning strategy used a simple whole-plasmid PCR method and type IIS restriction enzyme assembly that facilitate the seamless insertion of diversity into any suitable phage coat protein or antibody scaffold. This method reproducibly produced 1 × 109 variants from just 10 transformations and the four libraries had relatively low bias with 82 to 86% of all sequences present as single copies. The functionality of both peptide and antibody libraries were demonstrated by selection of ligands with specific binding properties by biopanning. The peptide library was used to epitope map a monoclonal antibody. The VHH libraries were pooled and used to select an antibody to recombinant human collagen type 1. [ABSTRACT FROM AUTHOR]

The Southern Ocean modulates the climate system by exchanging heat and carbon dioxide (CO2) between the atmosphere and deep ocean. While this region plays an outsized role in the global oceanic anthropogenic carbon uptake, CO2 is also released to the atmosphere across large swaths of the Antarctic Circumpolar Current (ACC). Southern Ocean outgassing has long been attributed to remineralized carbon from upwelled deep water, but the precise mechanisms by which this water reaches the surface are not well constrained from observations. Using data from a novel array of autonomous biogeochemical profiling floats, we examine Southern Ocean air‐sea CO2 fluxes and the pathways that transfer carbon from the ocean interior into the mixed layer where air‐sea exchange occurs. These float‐based flux estimates of unprecedented spatial resolution indicate that carbon outgassing occurs predominantly in the Indo‐Pacific sector of the ACC due to variations in the mean surface ocean partial pressure of CO2 (pCO2). We show that this zonal asymmetry in surface pCO2, and consequently air‐sea carbon fluxes, stems primarily from regional variability in the mixed‐layer entrainment of upwelled carbon‐rich deep water. These results suggest that a sustained circumpolar observing system is crucial to monitor future changes in oceanic carbon release and uptake. Plain Language Summary: The Southern Ocean, which surrounds Antarctica, helps regulate the global climate system by sequestering atmospheric heat and carbon dioxide (CO2) in the deep ocean. Although this region makes a significant contribution to the total oceanic carbon uptake, there are also locations in the Southern Ocean where CO2 is released back into the atmosphere. Understanding what controls these patterns of air‐sea carbon exchange is necessary to improve climate models and prepare for the effects of climate change. However, studying the Southern Ocean carbon cycle is difficult due to the lack of observations from this remote environment. Here, we use new data collected by autonomous biogeochemical floats to examine air‐sea carbon fluxes throughout the Southern Ocean. We find that ocean carbon release occurs preferentially in the Indo‐Pacific sector of the Southern Ocean due to systematic differences between basins in the transport of subsurface carbon from the deep ocean into the mixed layer—the portion of the upper ocean that is in direct contact with the atmosphere. These results suggest that collecting data from all sectors of the Southern Ocean is crucial to monitor future changes in the ocean carbon sink. Key Points: Autonomous biogeochemical floats reveal that carbon outgassing occurs predominantly in the Indo‐Pacific sector of the Southern OceanAsymmetry in carbon outgassing is driven by systematic interbasin variations in the mixed‐layer entrainment of carbon‐rich deep waterExpanded data coverage, particularly circumpolar sampling, is necessary to accurately capture Southern Ocean carbon sink variability [ABSTRACT FROM AUTHOR]

Pollen metabarcoding is emerging as a powerful tool for ecological research and offers unprecedented scale in citizen science projects for environmental monitoring via honey bees. Biases in metabarcoding can be introduced at any stage of sample processing and preservation is at the forefront of the pipeline. While in metabarcoding studies pollen has been preserved at − 20 °C (FRZ), this is not the best method for citizen scientists. Herein, we compared this method with ethanol (EtOH), silica gel (SG) and room temperature (RT) for preservation of pollen collected from hives in Austria and Denmark. After ~ 4 months of storage, DNAs were extracted with a food kit, and their quality and concentration measured. Most DNA extracts exhibited 260/280 absorbance ratios close to the optimal 1.8, with RT samples from Austria performing slightly worse than FRZ and SG samples (P < 0.027). Statistical differences were also detected for DNA concentration, with EtOH samples producing lower yields than RT and FRZ samples in both countries and SG in Austria (P < 0.042). Yet, qualitative and quantitative assessments of floral composition obtained using high-throughput sequencing with the ITS2 barcode gave non-significant effects of preservation methods on richness, relative abundance and Shannon diversity, in both countries. While freezing and ethanol are commonly employed for archiving tissue for molecular applications, desiccation is cheaper and easier to use regarding both storage and transportation. Since SG is less dependent on ambient humidity and less prone to contamination than RT, we recommend SG for preserving pollen for metabarcoding. SG is straightforward for laymen to use and hence robust for widespread application in citizen science studies. [ABSTRACT FROM AUTHOR]

It has been hypothesized that submesoscale flows play an important role in the vertical transport of climatically important tracers, due to their strong associated vertical velocities. However, the multiscale, nonlinear, and Lagrangian nature of transport makes it challenging to attribute proportions of the tracer fluxes to certain processes, scales, regions, or features. Here we show that criteria based on the surface vorticity and strain joint probability distribution function (JPDF) effectively decompose the surface velocity field into distinguishable flow regions, and different flow features, like fronts or eddies, are contained in different flow regions. The JPDF has a distinct shape and approximately parses the flow into different scales, as stronger velocity gradients are usually associated with smaller scales. Conditioning the vertical tracer transport on the vorticity–strain JPDF can therefore help to attribute the transport to different types of flows and scales. Applied to a set of idealized Antarctic Circumpolar Current simulations that vary only in horizontal resolution, this diagnostic approach demonstrates that small-scale strain-dominated regions that are generally associated with submesoscale fronts, despite their minuscule spatial footprint, play an outsized role in exchanging tracers across the mixed layer base and are an important contributor to the large-scale tracer budgets. Resolving these flows not only adds extra flux at the small scales, but also enhances the flux due to the larger-scale flows. [ABSTRACT FROM AUTHOR]