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Large satellite discrepancies and model biases in representing precipitation over the Southern Ocean (SO) are related directly to the region's limited surface observations of precipitation. To help address this knowledge gap, the study investigated the precipitation characteristics and rain rate retrievals over the remote SO using ship‐borne data of the Ocean Rainfall And Ice‐phase precipitation measurement Network disdrometer (OceanRAIN) and dual‐polarimetric C‐band radar (OceanPOL) aboard the Research Vessel (RV) Investigator in the Austral warm seasons of 2016–2018. Seven distinct synoptic types over the SO were analyzed based on their radar polarimetric signatures, surface precipitation phase, and rain microphysical properties. OceanRAIN observations revealed that the SO precipitation was dominated by drizzle and light rain, with small‐sized raindrops (diameter <1 mm) constituting up to 47% of total accumulation. Precipitation occurred most frequently over the warm sector of extratropical cyclones, while concentrations of large‐sized raindrops (diameter >3 mm) were prominent over synoptic types with colder and more convectively unstable environments. OceanPOL observations complement and extend the surface precipitation properties sampled by OceanRAIN, providing unique information to help characterize the variety of potential precipitation types and associated mechanisms under different synoptic conditions. Raindrop size distributions (DSD) measured with OceanRAIN over the SO were better characterized by analytical DSD forms with two‐shape parameters than single‐shape parameters currently implemented in satellite retrieval algorithms. This study also revised a rainfall retrieval algorithm for C‐band radars to reflect the large amount of small drops and provide improved radar rainfall estimates over the SO. Precipitation is a major component of the hydrologic cycle in high‐latitude regions including the remote Southern Ocean (SO). However, large differences continue to exist among current precipitation products in the region, owing in part to the absence of high‐quality surface observational records suitable for evaluation across a range of temporal and spatial scales. This work uses two instruments aboard the RV Investigator over the Australian sector of the SO in the Austral warm seasons of 2016–2018: the OceanRAIN disdrometer and OceanPOL radar. We found variability in radar features and surface precipitation properties among seven distinct synoptic conditions over the SO. This work also discussed two important findings related to remote sensing retrievals of SO rain. First, we demonstrated why the rainfall retrieval assumptions in satellite algorithms may need to be refined to account for the unique rainfall properties in the SO. Second, we formulated a new set of equations suitable for shipborne C‐band radars in improving rain rate estimates over the region. This work leads toward more accurate, high‐resolution estimates of precipitation over the measurement‐sparse SO to better understand a range of climatological and meteorological processes in the region. Different synoptic types across the Southern Ocean exhibit distinctive polarimetric signatures and surface precipitation propertiesSmall raindrops of less than one millimeter contribute up to 47% of total accumulation during the Austral warm seasons over the regionA new formulation for radar rainfall estimates that reflects the large numbers of small drops over the Southern Ocean is proposed Different synoptic types across the Southern Ocean exhibit distinctive polarimetric signatures and surface precipitation properties Small raindrops of less than one millimeter contribute up to 47% of total accumulation during the Austral warm seasons over the region A new formulation for radar rainfall estimates that reflects the large numbers of small drops over the Southern Ocean is proposed

The persistent Southern Ocean (SO) shortwave radiation biases in climate models and reanalyses have been associated with the poor representation of clouds, precipitation, aerosols, the atmospheric boundary layer, and their intrinsic interactions. Capitalizing on shipborne observations collected during the Clouds Aerosols Precipitation Radiation and atmospheric Composition Over the Southern Ocean 2016 and 2018 field campaigns, this research investigates and characterizes cloud and precipitation processes from synoptic to micro scales. Distinct cloud and precipitation regimes are found to correspond to the seven thermodynamic clusters established using a K‐means clustering technique, while less distinctions are evident using the cyclone and (cold) front compositing methods. Cloud radar and disdrometer data reveal that light precipitation is common over the SO with higher intensities associated with cyclonic and warm frontal regions. Multiple lines of evidence suggest the presence of diverse microphysical features in several cloud regimes, including the likely dominance of ice aggregation in deep precipitating clouds. Signatures of mixed phase, and in some cases, riming were detected in shallow convective clouds away from the frontal conditions. Two of the K‐means clusters with contrasting cloud and precipitation properties are observed over the high‐latitude SO and coastal Antarctica, suggesting distinct physical processes therein. Through a single case study, in‐situ and remote‐sensing data collected by an overflight of the Southern Ocean Clouds Radiation Aerosol Transport Experimental Study were also evaluated and complement the ship‐based analysis. The current generation of climate models and reanalyses products have difficulties in properly representing the radiative balance over the Southern Ocean (SO), which can be traced to the poor understanding of clouds and precipitation processes in this region. The remote location of the SO is a key factor for the lack of field observations that allow the scientific community to address the above‐mentioned problem. However, recent coordinated field campaigns have collected an unprecedented amount of data, offering new opportunities to explore this understudied region. This research paper aims to study clouds and precipitation processes over the SO using shipborne data collected from two field campaigns in 2016 and 2018. Using different synoptic classification techniques, we identify unique macro and micro cloud and precipitation behaviors that correspond to the various weather patterns across a wide range of latitudes. In addition, we use aircraft observations collected from an overflight to evaluate and complement our analysis of the shipborne data. The study offers a framework that may help better understand the nature of the model biases over the SO. Distinct cloud and precipitation regimes correspond to the Southern Ocean synoptics, defined using a sounding K‐means clustering techniqueEvidence suggests diverse microphysical features, like mixed phase in shallow convection and ice aggregation in deep precipitating cloudsTwo unique synoptic patterns have unique cloud and precipitation properties over the high‐latitudes, where climate models have large biases Distinct cloud and precipitation regimes correspond to the Southern Ocean synoptics, defined using a sounding K‐means clustering technique Evidence suggests diverse microphysical features, like mixed phase in shallow convection and ice aggregation in deep precipitating clouds Two unique synoptic patterns have unique cloud and precipitation properties over the high‐latitudes, where climate models have large biases

Owl monkeys Aotusspp have the potential to be a great model to accomplish a thorough integration of zoo and field research. Their most salient features are their nocturnal habits, monogamous social organization and paternal care, features that should make them of interest to the public. Following a brief historical perspective on our knowledge of owl monkey biology, I describe in detail, drawing from research with both captive and wild animals, those aspects that make owl monkeys unusual among primates and mammals. First, owl monkeys are the only anthropoids with nocturnal habits, and the study of their remarkable activity patterns has benefited enormously from an integrated approach that combined field research with research in semi‐natural conditions and the laboratory. Second, up until recently, our understanding of social monogamy and the involvement of the ♂♂ in infant care, two defining characteristics of the genus, have been primarily informed by studies of captive individuals. In the future, a truly integrated laboratory–field approach that focuses on certain areas that cannot be examined in only one or the other setting (e.g. reproductive biology, communication, energetics) will offer unique opportunities for synergistic interactions between zoo and field research that will have both intellectual and practical benefits.

A bacterium, Pseudomonas sp. strain C1S1, able to grow on 2,4,6-trinitrotoluene (TNT), 2,4- and 2,6-dinitrotoluene, and 2-nitrotoluene as N sources, was isolated. The bacterium grew at 30 degrees C with fructose as a C source and accumulated nitrite. Through batch culture enrichment, we isolated a derivative strain, called Pseudomonas sp. clone A, which grew faster on TNT and did not accumulate nitrite in the culture medium. Use of TNT by these two strains as an N source involved the successive removal of nitro groups to yield 2,4- and 2,6-dinitrotoluene, 2-nitrotoluene, and toluene. Transfer of the Pseudomonas putida TOL plasmid pWW0-Km to Pseudomonas sp. clone A allowed the transconjugant bacteria to grow on TNT as the sole C and N source. All bacteria in this study, in addition to removing nitro groups from TNT, reduced nitro groups on the aromatic ring via hydroxylamine to amino derivatives. Azoxy dimers probably resulting from the condensation of partially reduced TNT derivatives were also found.

The development of tolerance in Pseudomonas putida DOT-T1 to toluene and related highly toxic compounds involves short- and long-term responses. The short-term response is based on an increase in the rigidity of the cell membrane by rapid transformation of the fatty acid cis-9,10-methylene hexadecanoic acid (C17:cyclopropane) to unsaturated 9-cis-hexadecenoic acid (C16:1,9 cis) and subsequent transformation to the trans isomer. The long-term response involves in addition to the changes in fatty acids, alterations in the level of the phospholipid polar head groups: cardiolipin increases and phosphatidylethanolamine decreases. The two alterations lead to increased cell membrane rigidity and should be regarded as physical mechanisms that prevent solvent penetrance. Biochemical mechanisms that decrease the concentration of toluene in the cell membrane also take place and involve: (i) a solvent exclusion system and (ii) metabolic removal of toluene via oxidation. Mutants unable to carry out cis --> trans isomerization of unsaturated lipids, that exhibit altered cell envelopes because of the lack of the OprL protein, or that are unable to exclude toluene from cell membranes are hypersensitive to toluene.