Electrochemical sulfate production from sulfide-containing wastewaters and integration with electrochemical nitrogen recovery.

Electrochemical methods can help manage sulfide in wastewater, which poses environmental and health concerns due to its toxicity, malodor, and corrosiveness. In addition, sulfur could be recovered as fertilizer and commodity chemicals from sulfide-containing wastewaters. Wastewater characteristics vary widely among wastewaters; however, it remains unclear how these characteristics affect electrochemical sulfate production. In this study, we evaluated how four characteristics of influent wastewaters (electrolyte pH, composition, sulfide concentration, and buffer strength) affect sulfide removal (sulfide removal rate, sulfide removal efficiency) and sulfate production metrics (sulfate production rate, sulfate production selectivity). We identified that electrolyte pH (3 × difference, i.e., 25.1 to 84.9 µM h-1 in average removal rate within the studied pH range) and sulfide concentration (16 × difference, i.e., 82.1 to 1347.2 µM h-1 in average removal rate) were the most influential factors for electrochemical sulfide removal. Sulfate production was most sensitive to buffer strength (6 × difference, i.e., 4.4 to 27.4 µM h-1 in average production rate) and insensitive to electrolyte composition. Together, these results provide recommendations for the design of wastewater treatment trains and the feasibility of applying electrochemical methods to varying sulfide-containing wastewaters. In addition, we investigated a simultaneous multi-nutrient (sulfur and nitrogen) process that leverages electrochemical stripping to further enhance the versatility and compatibility of electrochemical nutrient recovery.

Limits and phylogenetic relationships of East Asian fishes in the subfamily Oxygastrinae (Teleostei: Cypriniformes: Cyprinidae).

The cyprinid subfamily Oxygastrinae is composed of a diverse group of fishes that has been taxonomically and phylogenetically problematic. Their great variation in appearance, life histories, and trophic diversity resulted in uncertainty regarding their relationships, which led to their historical classification across many disparate subfamilies. The phylogenetic relationships of Oxygastrinae are resolved based on sequence data from four loci: cytochrome b, cytochrome c oxidase I, opsin, and recombination activating gene 1. A combined data matrix consisting of 4114 bp for 144 taxa was compiled and analyzed using maximum likelihood and parsimony optimality criteria. The subfamily Oxygastrinae is recovered as a monophyletic group that includes Ancherythroculter, Aphyocypris, Candidia, Chanodichthys, Ctenopharyngodon, Culter, Distoechodon, Elopichthys, Hainania, Hemiculter, Hemiculterella, Hemigrammocypris, Hypophthalmichthys, Ischikauia, Macrochirichthys, Megalobrama, Metzia, Mylopharyngodon, Nicholsicypris, Nipponocypris, Ochetobius, Opsariichthys, Oxygaster, Parabramis, Parachela, Paralaubuca, Pararasbora, Parazacco, Plagiognathops, Pseudobrama, Pseudohemiculter, Pseudolaubuca, Sinibrama, Squaliobarbus, Toxabramis, Xenocyprioides, Xenocypris, Yaoshanicus, and Zacco. Of these genera, the following were found to be monophyletic: Aphyocypris, Distoechodon, Hypophthalmichthys, Nipponocypris, Opsariichthys, Parachela, Paralaubuca, Plagiognathops, Xenocyprioides, and Xenocypris. The following genera were not monophyletic: Metzia, Hemiculter, Toxabramis, Ancherythroculter, Chanodichthys, Culter, Megalobrama. The remainder are either monotypic or were represented by only a single species. Four genera not examined in this study are provisionally classified in Oxygastrinae: Anabarilius, Longiculter, Pogobrama, and Rasborichthys.

Phylogeny of the gudgeons (Teleostei: Cyprinidae: Gobioninae).

The members of the cyprinid subfamily Gobioninae, commonly called gudgeons, form one of the most well-established assemblages in the family Cyprinidae. The subfamily is a species-rich group of fishes, these fishes display diverse life histories, appearances, and behavior. The phylogenetic relationships of Gobioninae are examined using sequence data from four loci: cytochrome b, cytochrome c oxidase I, opsin, and recombination activating gene 1. This investigation produced a data matrix of 4114 bp for 162 taxa that was analyzed using parsimony, maximum likelihood, and Bayesian inference methods. The phylogenies our analyses recovered corroborate recent studies on the group. The subfamily Gobioninae is monophyletic and composed of three major lineages. We find evidence for a Hemibarbus-Squalidus group, and the tribes Gobionini and Sarcocheilichthyini, with the Hemibarbus-Squalidus group sister to a clade of Gobionini-Sarcocheilichthyini. The Hemibarbus-Squalidus group includes those two genera; the tribe Sarcocheilichthyini includes Coreius, Coreoleuciscus, Gnathopogon, Gobiocypris, Ladislavia, Paracanthobrama, Pseudorasbora, Pseudopungtungia, Pungtungia, Rhinogobio, and Sarcocheilichthys; the tribe Gobionini includes Abbottina, Biwia, Gobio, Gobiobotia, Huigobio, Microphysogobio, Platysmacheilus, Pseudogobio, Romanogobio, Saurogobio, and Xenophysogobio. The monotypic Acanthogobio is placed into the synonymy of Gobio. We tentatively assign Belligobio to the Hemibarbus-Squalidus group and Mesogobio to Gobionini; Paraleucogobio and Parasqualidus remain incertae sedis. Based on the topologies presented, the evolution of swim bladder specializations, a distinctive feature among cyprinids, has occurred more than once within the subfamily.

Systematics of the subfamily Danioninae (Teleostei: Cypriniformes: Cyprinidae).

The members of the cyprinid subfamily Danioninae form a diverse and scientifically important group of fishes, which includes the zebrafish, Danio rerio. The diversity of this assemblage has attracted much scientific interest but its monophyly and the relationships among its members are poorly understood. The phylogenetic relationships of the Danioninae are examined herein using sequence data from mitochondrial cytochrome b, mitochondrial cytochrome c oxidase I, nuclear opsin, and nuclear recombination activating gene 1. A combined data matrix of 4117 bp for 270 taxa was compiled and analyzed. The resulting topology supports some conclusions drawn by recent studies on the group and certain portions of the traditional classification, but our results also contradict key aspects of the traditional classification. The subfamily Danioninae is not monophyletic, with putative members scattered throughout Cyprinidae. Therefore, we restrict Danioninae to the monophyletic group that includes the following genera: Amblypharyngodon, Barilius, Cabdio, Chela, Chelaethiops, Danio, Danionella, Devario (including Inlecypris), Esomus, Horadandia, Laubuca, Leptocypris, Luciosoma, Malayochela, Microdevario, Microrasbora, Nematabramis, Neobola, Opsaridium, Opsarius, Paedocypris, Pectenocypris, Raiamas, Rasbora (including Boraras and Trigonostigma), Rasboroides, Salmostoma, Securicula, and Sundadanio. This Danioninae sensu stricto is divided into three major lineages, the tribes Chedrini, Danionini, and Rasborini, where Chedrini is sister to a Danionini-Rasborini clade. Each of these tribes is monophyletic, following the restriction of Danioninae. The tribe Chedrini includes a clade of exclusively African species and contains several genera of uncertain monophyly (Opsarius, Raiamas, Salmostoma). Within the tribe Rasborini, the species-rich genus Rasbora is rendered non-monophyletic by the placement of two monophyletic genera, Boraras and Trigonostigma, hence we synonymize those two genera with Rasbora. In the tribe Danionini, the miniature genus Danionella is recovered as the sister group of Danio, with D. nigrofasciatus sister to D. rerio.

Reconstructing the phylogenetic relationships of the earth's most diverse clade of freshwater fishes--order Cypriniformes (Actinopterygii: Ostariophysi): a case study using multiple nuclear loci and the mitochondrial genome.

The order Cypriniformes is the most diverse clade of freshwater fishes and is natively distributed on all continents except South America, Australia, and Antarctica. Despite the diversity of the group and the fundamental importance of these species in both ecosystems and human culture, relatively little has been known about their relationships relative to their diversity. In recent years, with an international effort investigating the systematics of the group, more information as to their genealogical relationships has emerged and species discovery and their descriptions have increased. One of the more interesting aspects of this group has been a traditional lack of understanding of the relationships of the families, subfamilies, and other formally or informally identified groups. Historical studies have largely focused on smaller groups of species or genera. Because of the diversity of this group and previously published whole mitochondrial genome evidence for relationships of major clades in the order, this clade serves as an excellent group to investigate the congruence between relationships reconstructed for major clades with whole mitogenome data and those inferred from a series of nuclear gene sequences. As descent has resulted in only one tree of life, do the phylogenetic relationships of these major clades converge on similar topologies using the large number of available characters through this suite of nuclear genes and previously published mitochondrial genomes? In this study we examine the phylogenetic relationships of major clades of Cypriniformes using previously published mitogenomes and four putative single-copy nuclear genes of the same or closely related species. Combined nuclear gene sequences yielded 3810bp, approximately 26% of the bp found in a single mitogenome; however homoplasy in the nuclear genes was measurably less than that observed in mitochondrial sequences. Relationships of taxa and major clades derived from analyses of nuclear and mitochondrial sequences were nearly identical and both received high support values. While some differences of individual gene trees did exist for species, it is predicted that these differences will be minimized with increased taxon sampling in future analyses.

Safety profile of amateur kickboxing among military and civilian competitors.

The purpose of this study was to identify match-ending injuries in amateur kickboxing (KB) among military and civilian competitors. A total of 148 competitors, of whom 5 were on active duty in the U.S. Air Force or Marine Corps, participated in amateur KB matches (N = 74) from 1999 to 2001. Match-ending injuries were observed and managed from ringside by one author (G.J.B.). Of all matches, 23 (31.1%) were stopped because of injury. Of the 23 matches, 15 (65.2%) ended because of traumatic brain injury, 4 (17.4%) because of orthopedic trauma, 3 (13.0%) because of thoracoabdominal trauma, and 1 (4.4%) because of ocular trauma. The incidence of traumatic brain injury was greater than that of all other match-ending injuries combined (p < 0.01). Because of the incidence and potentially serious sequelae of injuries associated with competitive KB, military commanders should exercise operational risk management in an attempt to safeguard personnel from unnecessary hazard.

Evaluation of the Gammarus pulex in situ feeding assay as a biomonitor of water quality: robustness, responsiveness, and relevance.

Biomonitoring using benthic macroinvertebrates has been used to assess water quality in Europe since the early 20th century. Most methods use community-level measurements, and the use of single-species responses has been limited, despite their potential benefits as sensitive, early warning indicators. Here we evaluate a single-species in situ assay in which the response is feeding inhibition of the freshwater amphipod Gammarus pulex. The assay was deployed in uncontaminated reference sites to quantify background variability in feeding rates and to elucidate sources of this variation. The ability of the assay to detect impacts of point-source discharges was assessed and the ecological relevance of the assay determined by comparing assay responses to aspects of community structure and functioning. Water temperature accounted for 76% of the variation in the feeding rate of animals deployed at uncontaminated sites, and summer deployments had a >90% power to detect a 30% inhibition in feeding. Inhibition of the situ feeding rate of G. pulex deployed downstream of a variety of point-source discharges ranged from 27 to 99.6%. Gammarus pulex is an important detritivore in stream communities, and a strong positive correlation existed between in situ feeding rate measured over 6 d and leaf decomposition measured over 28 d. A positive correlation also existed between in situ feeding and macroinvertebrate diversity and a biotic index. The G. pulex in situ feeding assay is a short-term sublethal biomonitor of water quality that is indicative of community- and ecosystem-level responses occurring over longer time periods. It is robust, responsive, and relevant.

Recovering cryptic diversity and ancient drainage patterns in eastern North America: historical biogeography of the Notropis rubellus species group (Teleostei: Cypriniformes).

The Central Highlands of North America contain a strikingly diverse assemblage of temperate freshwater fishes and have long been a focus of biogeographic studies. The rosyface shiner complex, Notropis rubellus and related species, is a member of this fauna exhibiting a disjunct highlands distribution occurring in the unglaciated regions of the Central Highlands and glaciated regions of the Central Lowlands. Until recently, N. rubellus was considered a single, widespread species exhibiting geographic variation in morphological characters. However, several studies have revealed that N. rubellus is a multi-species complex with closely related species endemic to drainages within each highland region. We examined genetic variation of the N. rubellus complex using a complete mtDNA cytochrome b gene sequence data set and combined mtDNA and published allozyme data sets. Parsimony and Bayesian analyses of the mitochondrial data set and parsimony analyses of a combined mitochondrial and allozyme data sets were largely consistent. Results of these analyses revealed ancient cryptic diversity within the N. rubellus complex that existed prior to the onset of Pleistocene glaciations. We identified seven strongly supported clades within the N. rubellus complex. Four clades are diagnosed as separate species (N. percobromus, N. rubellus, N. micropteryx and N. suttkusi) and three clades may represent undescribed forms. Relationships among these groups and their biogeographical patterns provided significant inferences on ichthyofaunal distributions in southeastern North America. These include the timing of the origin of the diversity, ancient drainage patterns and barriers to dispersal in the Central Highlands. The observation of increased diversity in N. rubellus suggests there may be greater diversity within other taxa with a similar distribution.

Phylogenetic relationships of Danio within the order Cypriniformes: a framework for comparative and evolutionary studies of a model species.

The evolutionary relationships of species of Danio and the monophyly and phylogenetic placement of the genus within the family Cyprinidae and subfamily Rasborinae provide fundamentally important phyloinformatics necessary for direct evaluations of an array of pertinent questions in modern comparative biology. Although the genus Danio is not one of the most diverse within the family, Danio rerio is one of the most important model species in biology. Many investigations have used this species or presumed close relatives to address specific questions that have lasting impact on the hypothesis and theory of development in vertebrates. Largely lacking from this approach has been a holistic picture of the exact phylogenetic or evolutionary relationships of this species and its close relatives. One thing that has been learned over the previous century is that many organismal attributes (e.g., developmental pathways, ecologies, behaviors, speciation) are historically constrained and their origins and functions are best explained via a phylogenetic approach. Herein, we provide a molecular evaluation of the phylogenetic placement of the model species Danio rerio within the genus Danio and among hypothesized closely related species and genera. Our analysis is derived from data using two nuclear genes (RAG1, rhodopsin) and five mitochondrial genes (ND4, ND4L, ND5, COI, cyt b) evaluated using parsimony, maximum likelihood, and Bayesian analyses. The family Cyprinidae is resolved as monophyletic but the subfamily Rasborinae (priority over Danioinae) is an unnatural assemblage. Danio is identified as a monophyletic group sister to a clade inclusive of the genera Chela, Microrasbora, Devario, and Inlecypris, not Devario nor Esomus as hypothesized in previous studies. Danio rerio is sister to D. kyathit among the species of Danio evaluated in this analysis. Microrasbora and Rasbora are non-monophyletic assemblages; however, Boraras is monophyletic.