Mapping particulate organic carbon in lakes across China using OLCI/Sentinel-3 imagery.

Remote sensing monitoring of particulate organic carbon (POC) concentration is essential for understanding phytoplankton productivity, carbon storage, and water quality in global lakes. Some algorithms have been proposed, but only for regional eutrophic lakes. Based on in-situ data (N = 1269) in 49 lakes across China, we developed a blended POC algorithm by distinguishing Type-I and Type-II waters. Compared to Type-I, Type-II waters had higher reflectance peak around 560 nm (>0.0125 sr-1) and mean POC (4.65 ± 4.11 vs. 2.66 ± 3.37 mg/L). Furthermore, because POC was highly related to algal production (r = 0.85), a three-band index (R2 = 0.65) and the phytoplankton fluorescence peak height (R2 = 0.63) were adopted to estimate POC in Type-I and Type-II waters, respectively. The novel algorithm got a mean absolute percent difference (MAPD) of 35.93 % and outperformed three state-of-the-art formulas with MAPD values of 40.56-76.42 %. Then, the novel algorithm was applied to OLCI/Sentinel-3 imagery, and we first obtained a national map of POC in 450 Chinese lakes (> 20 km2), which presented an apparent spatial pattern of "low in the west and high in the east". In brief, water classification should be considered when remotely monitoring lake POC concentration over a large area. Moreover, a process-oriented method is required when calculating water column POC storage from satellite-derived POC concentrations in type-II waters. Our results contribute substantially to advancing the dynamic observation of the lake carbon cycle using satellite data.

Genome sequencing and multifaceted taxonomic analysis of novel strains of violacein-producing bacteria and non-violacein-producing close relatives.

Violacein is a water-insoluble violet pigment produced by various Gram-negative bacteria. The compound and the bacteria that produce it have been gaining attention due to the antimicrobial and proposed antitumour properties of violacein and the possibility that strains producing it may have broad industrial uses. Bacteria that produce violacein have been isolated from diverse environments including fresh and ocean waters, glaciers, tropical soils, trees, fish and the skin of amphibians. We report here the isolation and characterization of six violacein-producing bacterial strains and three non-violacein-producing close relatives, each isolated from either an aquatic environment or moist food materials in northern California, USA. For each isolate, we characterized traditional phenotypes, generated and analysed draft genome sequences, and carried out multiple types of taxonomic, phylogenetic and phylogenomic analyses. Based on these analyses we assign putative identifications to the nine isolates, which include representatives of the genera Chromobacterium, Aquitalea, Iodobacter, Duganella, Massilia and Janthinobacterium. In addition, we discuss the utility of various metrics for taxonomic assignment in these groups including average nucleotide identity, whole genome phylogenetic analysis and extent of recent homologous recombination using the software program PopCOGenT.

Draft Genome Sequences and Genomic Analysis for Pigment Production in Bacteria Isolated from Blue Discolored Soymilk and Tofu.

Cold-tolerant bacteria are known to contaminate and cause defects in refrigerated foods. Defects in food products can be observed as changes in appearance, texture, and/or flavor that detract from the product's intended look, feel, or taste. Two distinct organisms were cultured from blue pigmented soymilk and tofu that had been left opened and expired in a home refrigerator. The blue coloration was reproduced when isolates were cultured in fresh, sterile soymilk. These strains also produced a variety of colony color morphologies when cultured on different media types. We report two draft genome sequences of the potential causative agents of blue discoloration of soy foods, Pseudomonas carnis strains UCD_MED3 and UCD_MED7 as well as the 16S rRNA gene sequences of co-occurring strains isolated from the defective soy samples but that did not cause blue discoloration when cultured in fresh soymilk; Serratia liquefaciens strains UCD_MED2 and UCD_MED5.

Storm impacts on phytoplankton community dynamics in lakes.

In many regions across the globe, extreme weather events such as storms have increased in frequency, intensity, and duration due to climate change. Ecological theory predicts that such extreme events should have large impacts on ecosystem structure and function. High winds and precipitation associated with storms can affect lakes via short-term runoff events from watersheds and physical mixing of the water column. In addition, lakes connected to rivers and streams will also experience flushing due to high flow rates. Although we have a well-developed understanding of how wind and precipitation events can alter lake physical processes and some aspects of biogeochemical cycling, our mechanistic understanding of the emergent responses of phytoplankton communities is poor. Here we provide a comprehensive synthesis that identifies how storms interact with lake and watershed attributes and their antecedent conditions to generate changes in lake physical and chemical environments. Such changes can restructure phytoplankton communities and their dynamics, as well as result in altered ecological function (e.g., carbon, nutrient and energy cycling) in the short- and long-term. We summarize the current understanding of storm-induced phytoplankton dynamics, identify knowledge gaps with a systematic review of the literature, and suggest future research directions across a gradient of lake types and environmental conditions.

Neisseria dumasiana sp. nov. from human sputum and a dog's mouth.

Three independent isolates of Gram-reaction-negative cocci collected from two New York State patients and a dog's mouth in California were subjected to a polyphasic analysis. The 16S rRNA gene sequence similarity among these isolates is 99.66 to 99.86 %. The closest species with a validly published name is Neisseria zoodegmatis (98.7 % 16S rRNA gene sequence similarity) with six additional species of the genus Neisseria with greater than 97 % similarity. Average nucleotide identity (ANI) and genome-to-genome distance calculator (GGDC 2.0) analysis on whole genome sequence data support the three novel isolates as being from a single species that is distinct from all other closely related species of the genus Neisseria. Phylogenetic analysis of 16S rRNA gene sequences and ribosomal multilocus sequence typing (rMLST) indicate the novel species belongs in the genus Neisseria. This assignment is further supported by the predominant cellular fatty acids composition of C16 : 0, summed feature 3 (C16 : 1ω7c/C15 : 0iso 2-OH), and C18 : 1ω7c, and phenotypic characters. The name Neisseria dumasiana sp. nov. is proposed, and the type strain is 93087T (=DSM 104677T=LMG 30012 T).

A Global View of Breast Tissue Banking.

The importance of accessing high quality clinical samples for translational research is now firmly recognised. Traditionally these samples were collected and curated by individuals with an interest in a particular disease type. In recent years the idea of centralising and storing tissue collections in the form of tissue banks or biobanks has developed. As a result a number of biobanks have been established in many different countries. These can be either single centres or multi centre collaborations, often in the form of a federated network. This chapter outlines the development of breast tissue banking in a global context and discusses some of the challenges that lie ahead for the field, in particular how to meet the growing needs of researchers, how to make the best use of donated samples and how to increase the visibility of samples residing in biobanks to researchers.