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Recent literature has demonstrated the sensitivity of mayflies to environmental contaminants. However, to date, there are no methods approved by the US Environmental Protection Agency for using sensitive insects like mayflies in whole-effluent toxicity or receiving water toxicity tests. The parthenogenetic mayfly Neocloeon triangulifer has been shown to be amenable to continuous culture in the laboratory, and methods have been described for its use in both acute and chronic toxicity studies. The goal of the present study was to investigate aspects of N. triangulifer testing and culturing methods that might require adjustment so that they are applicable for testing effluents and receiving waters in a short-term exposure. To this end, the influence of organism age, test duration, and test temperature on sensitivity to NaCl as a reference toxicant were tested (concentrations ranging from 182 to 2489 mg/L). Further studies were conducted to assess the utility of commercially available diets and the influence of nutrient amendment of water on organism growth and sensitivity. Seven-day NaCl tests started with less than 24-h-old larvae were similar in sensitivity to 14-day and full life chronic tests, and were much more sensitive than those started with 7-day-old organisms. Reducing test temperature from 25 °C to 22 °C had a minor influence on culture timing, and little impact on sensitivity to NaCl. In other experiments, reconstituted test water supplemented with nutrients to potentially improve in-test food quality had minimal effect on growth at 7 days and did not significantly alter acute sensitivity to NaCl relative to unamended reconstituted water. A suitable commercially available, ready-to-feed diet substitute for cultured diatoms was not found. Testing N. triangulifer in effluents or receiving waters with the methods recommended will complement similar methods for Ceriodaphnia dubia. Environ Toxicol Chem 2022;41:2758-2768. © 2022 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Packed cell volume (PCV) is commonly used to assess and monitor red blood cell count in animals, but the results can be altered if inappropriate ratios of anticoagulant/blood are used. The purpose of this study was to determine the effect of ideally filled, overfilled, and underfilled K3 ethylenediaminetetraacetic acid (EDTA) tubes with various volumes of healthy dog blood on centrifuged PCV. Six milliliters of blood was obtained from 94 blood donors each. Initial distribution was injected into two nonheparinized microhematocrit tubes. The remainder was instilled into 1.3 mL K3 EDTA spray-dried tubes as 1.5 mL, 1.3 mL, 0.75 mL, 0.5 mL, and 0.25 mL aliquots. Normality was determined using the D’agostino–Pearson method and by visual examination of histograms. Data were analyzed using a repeated-measures analysis of variance with post hoc testing using Tukey’s test. There is a statistically significant decrease in the PCV between all groups with progressive underfilling of tubes (P < .0001). The closest difference is between 1.5 and 1.3 mL (P = .0138). Our study suggested that underfilling K3 EDTA tubes significantly and negatively influences the PCV in healthy dogs. Using underfilled K3 EDTA tubes result in a lower PCV compared with directly filled microhematocrit tubes without anticoagulant.

Aquatic insects are poorly represented in water quality criteria, and previous studies have suggested a lack of sensitivity in acute toxicity tests despite observational studies demonstrating the contrary. Our objectives were to determine the toxicity of nickel (Ni) and zinc (Zn) to the mayfly Neocloeon triangulifer in fed acute (96-h) and chronic exposures to estimate aqueous effect concentrations while acknowledging the importance of dietary exposure for these insects. For the chronic tests, we conducted preliminary full-life cycle (~25-30 d) and subchronic (14 d) exposures to compare the relative sensitivity of the 2 test durations under similar conditions (i.e., feeding rates). Observing similar sensitivity, we settled on 14 d as the definitive test duration. Furthermore, we conducted experiments to determine how much food could be added to a given volume of water while minimally impacting dissolved metal recovery; a ratio of food dry mass to water volume (

Elevated nitrate (NO3 ) and sulfate (SO4 ) in surface water are of global concern, and studies are needed to generate toxicity data to develop environmental guideline values for NO3 and SO4 . The present study was designed to fill existing gaps in toxicity databases by determining the acute and/or chronic toxicity of NO3 (tested as NaNO3 ) to a unionid mussel (Lampsilis siliquoidea), a midge (Chironomus dilutus), a fish (rainbow trout, Oncorhynchus mykiss), and 2 amphibians (Hyla versicolor and Lithobates sylvaticus), and to determine the acute and/or chronic toxicity of SO4 (tested as Na2 SO4 ) to 2 unionid mussels (L. siliquoidea and Villosa iris), an amphipod (Hyalella azteca), and 2 fish species (fathead minnow, Pimephales promelas and O. mykiss). Among the different test species, acute NO3 median effect concentrations (EC50s) ranged from 189 to >883 mg NO3 -N/L, and chronic NO3 20% effect concentrations (EC20s) based on the most sensitive endpoint ranged from 9.6 to 47 mg NO3 -N/L. The midge was the most sensitive species, and the trout was the least sensitive species in both acute and chronic NO3 exposures. Acute SO4 EC50s for the 2 mussel species (2071 and 2064 mg SO4 /L) were similar to the EC50 for the amphipod (2689 mg SO4 /L), whereas chronic EC20s for the 2 mussels (438 and 384 mg SO4 /L) were >2-fold lower than the EC20 of the amphipod (1111 mg SO4 /L), indicating the high sensitivity of mussels in chronic SO4 exposures. However, the fathead minnow, with an EC20 of 374 mg SO4 /L, was the most sensitive species in chronic SO4 exposures whereas the rainbow trout was the least sensitive species (EC20 > 3240 mg SO4 /L). The high sensitivity of fathead minnow was consistent with the finding in a previous chronic Na2 SO4 study. However, the EC20 values from the present study conducted in test water containing a higher potassium concentration (3 mg K/L) were >2-fold greater than those in the previous study at a lower potassium concentration (1 mg K/L), which confirmed the influence of potassium on chronic Na2 SO4 toxicity to the minnow. Environ Toxicol Chem 2020;39:1071-1085. © 2020 SETAC.

While information professionals are not expected to be experts in law, they are experts in understanding the link between access to information and the realization of justice and human rights. This chapter investigates the role of the information professional in the fulfillment of the right to asylum, particularly in the context of contemporary asylum seekers at the US–Mexico border, volatile information landscapes, and the legal and historical framework in the United States for seeking asylum.

We studied biotic ligand model (BLM) predictions of the toxicity of nickel (Ni) and zinc (Zn) in natural waters from Illinois and Minnesota, USA, which had combinations of pH, hardness, and dissolved organic carbon (DOC) more extreme than 99.7% of waters in a nationwide database. We conducted 7-day chronic tests with Ceriodaphnia dubia and 96-hour acute and 14-day chronic tests with Neocloeon triangulifer and estimated median lethal concentrations and 20% effect concentrations for both species. Toxicity of Ni and Zn to both species differed among test waters by factors from 8 (Zn tests with C. dubia) to 35 (Zn tests with N. triangulifer). For both species and metals, tests with Minnesota waters (low pH and hardness, high DOC) showed lower toxicity than Illinois waters (high pH and high hardness, low DOC). Recalibration of the Ni BLM to be more responsive to pH-related changes improved predictions of Ni toxicity, especially for C. dubia. For the Zn BLM, we compared several input data scenarios, which generally had minor effects on model performance scores (MPS). A scenario that included inputs of modeled dissolved inorganic carbon and measured Al and Fe(III) produced the highest MPS values for tests with both C. dubia and N. triangulifer. Overall, the BLM framework successfully modeled variation in toxicity for both Zn and Ni across wide ranges of water chemistry in tests with both standard and novel test organisms. Environ Toxicol Chem 2021;40:3049-3062. © 2021 SETAC. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

Objectives/Hypothesis We aimed to determine whether there was a difference between core and surface bacteriology of Finnish adults with recurrent or chronic tonsillitis to understand whether a surface swab is worthwhile and which bacteria are involved. Study Design Case series. Methods Uninflamed tonsillar surface swabs and core biopsies were taken prior to and during surgery, respectively, in 103 patients aged 16 to 66 years undergoing tonsillectomy for recurrent or chronic tonsillitis. The McNemar test was used to determine differences between the surface and core in the most prevalent bacterial species. Results Twenty-seven bacterial species were isolated in addition to normal flora and were more commonly found in the core (1.11 surface and 4.75 core bacteria isolated per patient). Viridans group streptococci were the most commonly detected bacteria, found in 88% of the patients, mainly in the core. The bacteria in general were mainly isolated from the core. Of the 10 most prevalent bacteria, only group C beta-hemolytic streptococci showed no difference between detection from core and surface swabs. Other bacteria found mainly in the core include Prevotella melaninogenica, Staphylococcus aureus, and fusobacteria. Conclusions There is discord between the surface and core bacteria. A different population of bacteria exists in the core, especially anaerobic bacteria, suggesting that a core sample may be useful in evaluating recurrent and chronic tonsillitis. Level of Evidence 4 Laryngoscope, 2019

Background: Laryngeal squamous cell carcinoma (LSCC) is rare in the young. Objectives: We characterized the clinical behavior of LSCC and assessed the presentation of second primary tumors (SPCs) in this patient population. Materials and methods: Data from the Finnish Cancer Registry (FCR) were used to identify an epidemiological series of LSCC patients diagnosed at the age of 40 years or under, during 1953-2012 in Finland. Data regarding primary treatment, survival, and SPCs were available. To further characterize the comorbidity and lifestyle factors of young patients with LSCC, institutional data were collected of patients treated at the Helsinki University Hospital during 1967-2012. Results: We identified 151 patients, with a mean follow-up of 252 months. The 10-year overall survival (OS) was 75% and the disease-specific survival was 84%. SPCs were diagnosed in 26% (n = 39), with a median delay of 28 years. Of the 35 patients in the institutional series from Helsinki, 22 (63%) were current or former smokers. LSCC recurred in 28% of patients. Conclusions and Significance: The delay to SPCs in young patients was significantly longer compared with the general LSCC population. As factors underlying this phenomenon cannot be identified by this retrospective study, further studies are warranted.

PurposeApproximately 20% of cancers are estimated to have a viral etiology. We aimed to investigate whether DNA of 8 human parvoviruses [bocavirus 1-4 (HBoV1-4), parvovirus B19 (B19V), protoparvoviruses (bufa-, tusa-, and cutavirus)] and 13 human polyomaviruses (HPyV) can be detected in oropharyngeal and oral cavity squamous cell carcinoma (OPSCC/OSCC), and in juvenile nasopharyngeal angiofibroma (JNA) tissue samples.MethodsFresh samples of seven JNA tissues and ten paired tissues of OSCC/OPSCC tumor and adjacent healthy tissues were collected. DNA extraction and real-time PCRs were performed to detect HBoV1-4, B19V, bufa- tusa- and cutavirus, and HPyV genomes.ResultsJNA specimens were negative for all parvoviruses tested, whereas one JNA sample was Merkel cell polyomavirus (MCPyV) DNA positive. The OSCC/OPSCC samples were negative for the human protoparvoviruses, HBoV1-4, and all human polyomaviruses, except for one patient that was MCPyV DNA positive in both healthy and tumor tissues. Seven OSCC/OPSCC patients were positive for B19V DNA, three of them in both healthy and cancerous tissues and three in only healthy tissues. Three of the B19V DNA-positive patients harbored viral genotype 1, three genotype 2, and one genotype 3B.ConclusionsThese are the first reports of MCPyV and B19V DNA being detected in JNA and OPSCC. The significance of viral DNA positivity is unclear. B19V DNA is known to remain in the tissues lifelong, however, it is of interest that there are some patients with B19 DNA in healthy tissue, but not in the corresponding cancer tissue.

Although standardized sediment toxicity testing methods have been developed for the amphipod Hyalella azteca, no standardized chronic water-only toxicity testing methods have been established. Furthermore, optimal feeding and water quality conditions for culturing and toxicity testing with this species remained unclear. The objective of the present study was to determine the food or combination of foods that best promotes survival, growth, and reproduction of the US Lab strain of Hyalella azteca under 42-d, water-only, static-renewal testing conditions. The authors conducted 7 42-d control (no toxicant) tests with various combinations of food (including Tetramin, yeast-cereal leaves-trout chow, diatoms, wheatgrass, alfalfa, and maple leaves) and substrate types (clean "unconditioned" Nitex screens vs "conditioned" Nitex screens that were colonized by live biofilms). Over all treatments, survival ranged from 18% to 96%, dry weight per individual from 0.084 mg to 1.101 mg, and reproduction from 0 young/female to 28.4 young/female. Treatments that included Tetramin tended to result in better performance than those that did not. In particular, treatments that included Tetramin and either conditioned screens or diatoms consistently had high survival, weight, and reproduction values as well as low variability among replicates (measured as coefficient of variation). A ramped Tetramin plus diatom suspension feeding regime appears to have the greatest potential to produce consistently good performance across laboratories using static-renewal systems. Environ Toxicol Chem 2016;35:2407-2415. © 2016 SETAC.

Lipid metabolic reprogramming is one hallmark of cancer. Lipid metabolism is regulated by numerous enzymes, many of which are targeted by several drugs on the market. We aimed to characterize the lipid alterations in oral squamous cell carcinoma (OSCC) as a basis for understanding its lipid metabolism, thus identifying potential therapeutic targets. We compared lipid species, classes, and glycerophospholipid (GPL) fatty acid species between paired tumor tissue and healthy oral tongue mucosa samples from 10 OSCC patients using a QExactive mass spectrometer. After filtering the 1370 lipid species identified, we analyzed 349 species: 71 were significantly increased in OSCC. The GPL metabolism pathway was most represented by the lipids differing in OSCC (P = .005). Cholesterol and the GPLs phosphatidylcholines, phosphatidylethanolamines, and phosphatidylinositols were most significantly increased in OSCC tissue (FC 1.8, 2.0, 2.1, and 2.3 and, P = .003, P = .005, P = .002, P = .007). In conclusion, we have demonstrated a shift in the lipid metabolism in these OSCC samples by characterizing the detailed landscape. Predominantly, cholesterol and GPL metabolism were altered, suggesting that interactions with sterol regulatory binding proteins may be involved. The FA composition changes of the GPLs suggest increased de novo lipogenesis.

Purpose Experimental design There are no blood biomarkers to detect early-stage oral cavity squamous cell carcinoma (OSCC) prior to clinical signs. Most OSCC incidence is associated with significant morbidity and poor survival. The authors aimed to use mass-spectrometry (MS) technology to find specific N-glycopeptides potentially serving as serum biomarkers for preclinical OSCC screening. Serum samples from 14 patients treated for OSCC (stage I or stage IV) with 12 age- and sex-matched controls are collected. Quantitative label-free N-glycoproteomics is performed, with MS/MS analysis of the statistically significantly different N-glycopeptides. Results Conclusions and clinical relevance Combined with a database search using web-based software (GlycopeptideID), MS/MS provided detailed N-glycopeptide information, including glycosylation site, glycan composition, and proposed structures. Thirty-eight tryptic N-glycopeptides are identified, having 19 unique N-glycosylation sites representing 14 glycoproteins. OSCC patients, including stage I tumors, can be differentiated from healthy controls based on the expression levels of these glycoforms. N-glycopeptides of IgG1, IgG4, haptoglobin, and transferrin have statistically significant different abundances between cases and controls. The authors are the first to suggest specific N-glycopeptides to serve as potential serum biomarkers to detect preclinical OSCC in patients. These N-glycopeptides are the lead candidates for validation as future diagnostic modalities of OSCC as early as stage I.

Objectives No prognostic or predictive biomarkers for oral squamous cell carcinoma (OSCC) exist. We aimed to discover novel proteins, altered in OSCC, to be further investigated as potential biomarkers, and to improve understanding about pathways involved in OSCC. Materials and Methods Proteomic signatures of seven paired healthy and OSCC tissue samples were identified using ultra-definition quantitative mass spectrometry, then analysed and compared using Anova, principal component analysis, hierarchical clustering and OPLS-DA modelling. A selection of significant proteins that were also altered in the serum from a previous study (PMID: 28632724 ) were validated immunohistochemically on an independent cohort (n = 66) to confirm immunopositivity and location within tumour tissue. Ingenuity Pathways Analysis was employed to identify altered pathways. Results Of 829 proteins quantified, 257 were significant and 72 were able to classify healthy vs OSCC using OPLS-DA modelling. We identified 19 proteins not previously known to be upregulated in OSCC, including prosaposin and alpha-taxilin. KIAA1217 and NDRG1 were upregulated in stage IVa compared with stage I tumours. Altered pathways included calcium signalling, cellular movement, haematological system development and function, and immune cell trafficking, and involved NF-kB and MAPK networks. Conclusions We found a set of proteins reliably separating OSCC tumour from healthy tissue, and multiple proteins differing between stage I and stage IVa OSCC. These potential biomarkers can be studied and validated in larger cohorts.

Field and laboratory studies have shown that mayflies (Ephemeroptera) tend to be relatively sensitive to elevated major ion concentrations, but little is known about how ionic composition influences these responses. The present study evaluated the acute toxicity of major ion salts to the mayfly Neocloeon triangulifer over a range of background water quality conditions. The mayfly was particularly sensitive to Na2 SO4 , with the median lethal concentration (LC50) of 1338 mg SO4 /L being lower than LC50s reported for 7 other species at that hardness. Increasing hardness of the dilution water from 30 to 150 mg/L (as CaCO3 ) resulted in doubling of LC50s for sodium salts, and an approximately 1.5-fold increase in LC50 for MgSO4 . Potassium salt toxicity was not strongly influenced by hardness, consistent with findings for other species. When hardness was held constant but the Ca to Mg ratio was manipulated, the ameliorative effect on Na2 SO4 and NaCl did not appear as strong as when hardness was varied; but for MgSO4 the amelioration relative to Ca activity was similar between the 2 experiments. The toxicity of K salts to N. triangulifer was similar to Na salts on a millimolar basis, which contrasts with several other species for which K salts have been much more toxic. In addition, the toxicity of KCl to N. triangulifer was not notably affected by Na concentration, as has been shown for Ceriodaphnia dubia. Finally, plotting LC50s in terms of ion activity (Cl, SO4 , Na, Mg, or K) over the range of Ca activities in dilution water resulted in significant positive relationships, with comparable slopes to those previously observed for C. dubia over the same range of Ca activities. Environ Toxicol Chem 2018;37:1330-1339. © 2018 SETAC.

Background The increasing incidence of oropharyngeal squamous cell carcinoma (OPSCC) is mainly related to human papillomavirus (HPV) infection. As OPSCCs are often diagnosed at an advanced stage, mortality and morbidity remain high. There are no diagnostic biomarkers for early detection of OPSCC. Methods Serum from 25 patients with stage I–II OPSCC, and 12 healthy controls, was studied with quantitative label-free proteomics using ultra-definition MSE. Statistical analyses were performed to identify the proteins most reliably distinguishing early-stage OPSCCs from controls. P16 was used as a surrogate marker for HPV. P16-positive and P16-negative tumours were analysed separately. Results With two or more unique proteins per identification, 176 proteins were quantified. A clear separation between patients with early-stage tumours and controls was seen in principal component analysis. Latent structures discriminant analysis identified 96 proteins, most reliably differentiating OPSCC patients from controls, with 13 upregulated and 83 downregulated proteins in study cases. The set of proteins was studied further with network, pathway and protein–protein interaction analyses, and found to participate in lipid metabolism, for example. Conclusions We found a set of serum proteins distinguishing early-stage OPSCC from healthy individuals, and suggest a protein set for further evaluation as a diagnostic biomarker panel for OPSCC.

The strain of Hyalella azteca (Saussure: Amphipoda) commonly used for aquatic toxicity testing in the United States has been shown to perform poorly in some standardized reconstituted waters frequently used for other test species. In 10-d and 42-d experiments, the growth and reproduction of the US laboratory strain of H. azteca was shown to vary strongly with chloride concentration in the test water, with declining performance observed below 15 mg/L to 20 mg/L. In contrast to the chloride-dependent performance of the US laboratory strain of H. azteca, growth of a genetically distinct strain of H. azteca obtained from an Environment Canada laboratory in Burlington, Ontario, Canada, was not influenced by chloride concentration. In acute toxicity tests with the US laboratory strain of H. azteca, the acute toxicity of sodium nitrate increased with decreasing chloride in a pattern similar not only to that observed for control growth, but also to previous acute toxicity testing with sodium sulfate. Subsequent testing with the Burlington strain showed no significant relationship between chloride concentration and the acute toxicity of sodium nitrate or sodium sulfate. These findings suggest that the chloride-dependent toxicity shown for the US laboratory strain may be an unusual feature of that strain and perhaps not broadly representative of aquatic organisms as a whole.

Although insects occur in nearly all freshwater ecosystems, few sensitive insect models exist for use in determining the toxicity of contaminants. The objectives of the present study were to adapt previously developed culturing and toxicity testing methods for the mayfly Neocloeon triangulifer (Ephemeroptera: Baetidae), and to further develop a method for chronic toxicity tests spanning organism ages of less than 24 h post hatch to adult emergence, using a laboratory cultured diatom diet. The authors conducted 96-h fed acute tests and full-life chronic toxicity tests with sodium chloride, sodium nitrate, and sodium sulfate. The authors generated 96-h median lethal concentrations (LC50s) of 1062 mg Cl/L (mean of 3 tests), 179 mg N-NO3/L, and 1227 mg SO4/L. Acute to chronic ratios ranged from 2.1 to 6.4 for chloride, 2.5 to 5.1 for nitrate, and 2.3 to 8.5 for sulfate. The endpoints related to survival and development time were consistently the most sensitive in the tests. The chronic values generated for chloride were in the same range as those generated by others using natural foods. Furthermore, our weight-versus-fecundity plots were similar to those previously published using the food culturing method on which the present authors' method was based, indicating good potential for standardization. The authors believe that the continued use of this sensitive mayfly species in laboratory studies will help to close the gap in understanding between standard laboratory toxicity test results and field-based observations of community impairment . Environ Toxicol Chem 2015;34:2126–2137. © 2015 SETAC

Efforts to control invasive bighead ( Hypophthalmichthys nobilis ) and silver carp ( H . molitrix ) may include harvest for human consumption. We measured concentrations of arsenic (As), mercury (Hg), and selenium (Se) in fillets from silver and bighead carp collected from the lower Illinois River, Illinois, USA, to determine whether concentrations were of health concern and differed by species, size, and location. Concentrations of total As were below detection limits in most bighead (92%) and silver (77%) carp fillets, whereas inorganic As was below detection limits in all samples. Mean Hg concentrations were greater in bighead (0.068 mg kg −1 ) than in silver carp (0.035 mg kg −1 ), and were smallest in carp from the confluence of the Illinois and Mississippi rivers. Mercury concentrations in fillets were positively correlated with body mass in both species. Concentrations of Hg were below the US Food and Drug Administration’s (USFDA) action level (1 ppm as methyl-Hg); however, concentrations in some bighead (70%) and silver (12%) carp fell within the range that would invoke a recommendation to limit meals in sensitive cohorts. Mean Se concentrations were greater in silver (0.332 mg kg −1 ) than in bighead (0.281 mg kg −1 ) carp fillets, and were below the 1.5 mg kg −1 limit for an unrestricted number of meals/month. The mean molar ratio of Se:Hg in fillets was lower in bighead (14.0) than in silver (29.1) carp and was negatively correlated with mass in both species Concentrations of Hg in bighead and silver carp fillets should be considered when assessing the risks associated with the use of these species as a protein source.

While it has been well established that increasing chloride concentration in water reduces the toxicity of nitrite to freshwater species, little work has been done to investigate the effect of chloride on nitrate toxicity. We conducted acute and chronic nitrate (as sodium nitrate) toxicity tests with the cladoceran Ceriodaphnia dubia and the amphipod Hyalella azteca (chronic tests only) over a range of chloride concentrations spanning natural chloride levels found in surface waters representative of watersheds of the Great Lakes Region. Chronic nitrate toxicity test results with both crustaceans were variable, with H. azteca appearing to be one of the more sensitive invertebrate species tested and C. dubia being less sensitive. While the variability in results for H. azteca were to an extent related to chloride concentration in test water that was distinctly not the case for C. dubia. We concluded that the chloride dependent toxicity of nitrate is not universal among freshwater crustaceans. An additional sodium chloride chronic toxicity test with the US Lab strain of H. azteca in the present study suggested that when present as predominantly sodium chloride and with relatively low concentrations of other ions, there is a narrow range of chloride concentrations over which this strain is most fit, and within which toxicity test data are reliable.

Total dissolved solids (TDS) represent the sum of all common ions (e.g., Na, K, Ca, Mg, chloride, sulfate, and bicarbonate) in freshwater. Currently, no federal water quality criteria exist for the protection of aquatic life for TDS, but because the constituents that constitute TDS are variable, the development of aquatic life criteria for specific ions is more practical than development of aquatic life criteria for TDS. Chloride is one such ion for which aquatic life criteria exist; however, the current aquatic life criteria dataset for chloride is more than 20 years old. Therefore, additional toxicity tests were conducted in the current study to confirm the acute toxicity of chloride to several potentially sensitive invertebrates: water flea (Ceriodaphnia dubia), fingernail clams (Sphaerium simile and Musculium transversum), snail (Gyraulus parvus), and worm (Tubifex tubifex), and determine the extent to which hardness and sulfate modify chloride toxicity. The results indicated a significant ameliorating effect of water hardness (calcium and magnesium) on chloride toxicity for all species tested except the snail; for example, the 48-h chloride median lethal concentration (LC50) for C. dubia at 50 mg/L hardness (977 mg Cl(-) /L) was half that at 800 mg/L hardness (1,836 mg Cl(-) /L). Conversely, sulfate over the range of 25 to 600 mg/L exerted a negligible effect on chloride toxicity to C. dubia. Rank order of LC50 values for chloride at a given water hardness was in the order (lowest to highest): S. simile

e18047Tongue cancer patients can be distinguished from healthy controls by specific N-glycopeptides found in serum. Background: There are no blood biomarkers to detect early-stage oral cavity squam...

The purpose of our study was to investigate the sub-lethal effects of millimeter wave carbon fibers (MWCF), a military obscurant, on filter-feeding freshwater invertebrates. We observed decreased survival, reproduction, and oxygen consumption in Daphnia magna at realistic loading rates. In experiments with the Asiatic clam (Corbicula fluminea), soft tissue dry weight and tissue condition index were not significantly different among control and MWCF exposed treatments; however, using a (15)N labeled alga as food, we observed decreased nitrogen turnover in tissues of clams exposed to MWCF, suggesting lower filtering or ingestion rates. Our findings combined with previous demonstrations of MWCF toxicity to green algae suggest that over a period of several months, bivalve growth may be inhibited, and cladoceran populations may be even more strongly affected by MWCF. Given that these fibers are persistent, further experiments should be conducted to determine the longer-term effects of contamination of water bodies with MWCF.

Multiple-choice experimental arenas, with sample compartments, were used to assess the response of fungus gnat, Bradysia sp. nr. coprophila (Lintner) (Diptera: Sciaridae), adults to varying light intensities in environmentally controlled walk-in chambers. Each sample compartment contained a yellow sticky card (2.5 × 2.5 cm) to capture fungus gnat adults. Under conditions of darkness, fungus gnat adults migrated randomly with no significant differences among the six sample compartments. Fungus gnat adults were observed to positively respond to light intensities less than 0.08374 μmol·m−2·s−1. In addition, adults responded to light intensities that were below the detection threshold of a photosynthetically active radiation light sensor. A higher percentage of fungus gnat adults (22% to 39%) were captured on yellow sticky cards in the sample compartments that were closest to a directional light source compared with sample compartments that were located further away from the light source (2% to 9%). Fungus gnat adults exhibited a significant response when exposed to two distinct ranges of light intensities (0.12 to 0.26 versus 0.87 to 1.02 μmol·m−2·s−1) with adults significantly more attracted to the highest light intensities (0.87 to 1.02 μmol·m−2·s−1). The results obtained in this study indicate that fungus gnat adults are positively phototactic, and as light intensity increases, they display a preference for those higher light intensities. It is possible that modifications in light intensity may be a feasible management strategy for alleviating problems with fungus gnats in greenhouses.

This study, consisting of three experiments, was designed to assess whether diatomaceous earth, when applied to the surface of growing media, reduces adult fungus gnat Bradysia sp. nr. coprophila (Diptera: Sciaridae) emergence or inhibits the females from laying eggs; and whether fungus gnat adults are attracted to the fungus Trichoderma harzianum T-22 (Rifai strain KRL-AG2) under laboratory conditions. In the first two experiments, diatomaceous earth was applied at two different thicknesses (3.1 and 6.3 mm) and conditions (dry and moist) to the surface of a growing medium (Universal SB 300 Mix) after the growing medium had been artificially inoculated with second or third instars of fungus gnats, or before female fungus gnat adults were released into each deli squat container. In the third experiment, preparations of the fungus T. harzianum at the highest recommended label rate (0.889 kg/m3) were amended into the growing medium and processed 24, 48, or 72 h before use in a series of three two-choice trials with a two-armed experimental arena. In the first two experiments, the dry or moist layers of diatomaceous earth, in general, did not affect fungus gnats in terms of preventing adult emergence or egg laying by the females. During the course of these experiments, we observed that the diatomaceous earth dry treatments expanded as a result of absorbing moisture from the growing medium, creating fissures that allowed the fungus gnat larvae to pupate and females to lay eggs. In the third experiment, fungus gnat adults were not attracted to the T. harzianum treatments in any of the trials.

Although insects occur in nearly all freshwater ecosystems, few sensitive insect models exist for use in determining the toxicity of contaminants. The objectives of the present study were to adapt previously developed culturing and toxicity testing methods for the mayfly Neocloeon triangulifer (Ephemeroptera: Baetidae), and to further develop a method for chronic toxicity tests spanning organism ages of less than 24 h post hatch to adult emergence, using a laboratory cultured diatom diet. The authors conducted 96-h fed acute tests and full-life chronic toxicity tests with sodium chloride, sodium nitrate, and sodium sulfate. The authors generated 96-h median lethal concentrations (LC50s) of 1062 mg Cl/L (mean of 3 tests), 179 mg N-NO3 /L, and 1227 mg SO4 /L. Acute to chronic ratios ranged from 2.1 to 6.4 for chloride, 2.5 to 5.1 for nitrate, and 2.3 to 8.5 for sulfate. The endpoints related to survival and development time were consistently the most sensitive in the tests. The chronic values generated for chloride were in the same range as those generated by others using natural foods. Furthermore, our weight-versus-fecundity plots were similar to those previously published using the food culturing method on which the present authors' method was based, indicating good potential for standardization. The authors believe that the continued use of this sensitive mayfly species in laboratory studies will help to close the gap in understanding between standard laboratory toxicity test results and field-based observations of community impairment.

In this study, we measured, under laboratory conditions, the direct and indirect effects of insecticides on mealybug destroyer, Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae), and parasitoid Leptomastix dactylopii Howard (Hymenoptera: Encyrtidae), natural enemies of citrus mealybug, Planococcus citri (Risso) (Homoptera: Pseudococcidae). The adult stages of both natural enemies were exposed to sprays of the insecticides buprofezin, pyriproxyfen, flonicamid, acetamiprid, dinotefuran, and clothianidin at label-recommended rates to assess direct mortality after 24, 48, and 72 h, respectively. The effects of the insecticides on L. dactylopii parasitization rate and percentage of parasitoid emergence also were monitored using the label and 4x the recommended label rate. Dinotefuran was extremely detrimental to the adult parasitoid at the label rate with 100% mortality after 24 h. Buprofezin, pyriproxyfen, and flonicamid were not harmful to L. dactylopii when applied at the label rate. At 4x the recommended label rate, dinotefuran, acetamiprid, and clothianidin were all harmful to the parasitoid with 100% mortality 72 h after application. Both buprofezin and flonicamid were not toxic to L. dactylopii with 100% adult survival after 72 h. Pyriproxyfen and flonicamid, at both the label and 4x the recommended label rate, did not negatively affect L. dactylopii parasitization rate or percentage of parasitoid emergence. Acetamiprid, dinotefuran, and clothianidin were toxic to C. montrouzieri adults with 100% mortality after 48 h, whereas buprofezin, pyriproxyfen, and flonicamid demonstrated minimal (10-20% mortality after 48 h) harmful effects to the predator. Based on the results from our study, the indirect effects of the insect growth regulator (IGR) buprofezin were not decisive; however, the IGR pyriproxyfen and the insecticide flonicamid were not directly or indirectly harmful to the predator C. montrouzieri and parastioid L. dactylopii, indicating that these insecticides are compatible with both natural enemies when used together for control of citrus mealybug in greenhouses and conservatories.

Fungus gnats (Bradysia spp.) are major insect pests in greenhouses. The adult stage is primarily a nuisance whereas the larval stage is directly responsible for plant injury by feeding on plant roots or tunneling into stems. Insecticides are used to deal with fungus gnat larvae in growing medium, although sometimes with limited success. This study evaluated the potential of using a soil amendment—diatomaceous earth (DE) incorporated into growing media—for controlling the fungus gnat Bradysia sp. nr. coprophila. Two experiments were conducted by testing a series of growing media containing various concentrations of diatomaceous earth, and several without diatomaceous earth. The effects of the growing media containing diatomaceous earth on both the 2nd and 3rd instars of fungus gnat larvae were determined by recording the number of adults captured on yellow sticky cards (2.5 × 2.5 cm). Based on the results obtained from both experiments, the addition of DE to growing medium, at the concentrations tested, did not negatively affect or increase efficacy against both the 2nd and 3rd instars. This suggests that incorporating DE into commercially available growing medium may not be beneficial to greenhouse producers. However, further research is needed to assess whether differential larval susceptibility and moisture content influence the ability of DE to control soil-dwelling arthropods.

The strain of Hyalella azteca (Saussure: Amphipoda) commonly used for aquatic toxicity testing in the United States has been shown to perform poorly in some standardized reconstituted waters frequently used for other test species. In 10-d and 42-d experiments, the growth and reproduction of the US laboratory strain of H. azteca was shown to vary strongly with chloride concentration in the test water, with declining performance observed below 15 mg/L to 20 mg/L. In contrast to the chloride-dependent performance of the US laboratory strain of H. azteca, growth of a genetically distinct strain of H. azteca obtained from an Environment Canada laboratory in Burlington, Ontario, Canada, was not influenced by chloride concentration. In acute toxicity tests with the US laboratory strain of H. azteca, the acute toxicity of sodium nitrate increased with decreasing chloride in a pattern similar not only to that observed for control growth, but also to previous acute toxicity testing with sodium sulfate. Subsequent testing with the Burlington strain showed no significant relationship between chloride concentration and the acute toxicity of sodium nitrate or sodium sulfate. These findings suggest that the chloride-dependent toxicity shown for the US laboratory strain may be an unusual feature of that strain and perhaps not broadly representative of aquatic organisms as a whole.

Fungus gnats, Bradysia spp., are major insect pests in greenhouses and interiorscapes. Management typically involves the use of either insecticides or biological control agents such as entomopathogenic nematodes. Efficacy trials provide information to greenhouse producers on the effectiveness of these management options. However, a simple procedure that rapidly evaluates the performance of control products against fungus gnat larvae is needed. Because fungus gnat larvae inhabit the growing medium, excess or deficient growing medium moisture may reduce adult fungus gnat emergence, thus confounding effects from efficacy trial treatments. Therefore, it is important to determine the amount of moisture and moisture content that results in the highest recovery of fungus gnat adults. We conducted two replicated experiments in a completely randomized design using a range of initial water volumes (treatments) and two larval stages (second and third) of the fungus gnat, Bradysia sp. nr. coprophila. The success of the procedure was based on the number of fungus gnat adults that emerged per treatment. In the first experiment, initial water volumes of 0, 25, 50, 75, 100, 150, and 200 mL were applied to 300 mL of a soilless growing medium consisting of 50% composted pine bark, 20% Canadian sphagnum peatmoss, 10% perlite, and 20% medium coarse vermiculite (SB300 Universal Mix). In general, the highest mean numbers (range, 11.2 to 14.6) of fungus gnat adults were recovered from growing medium treated with 50, 75, and 100 mL of water. In the second experiment, initial water volumes (treatments) of 50, 55, 60, 65, 70, and 75 mL were applied to 300 mL of the soilless growing medium (SB300 Universal Mix). There were no significant differences in the mean number of fungus gnat adults recovered regardless of the larval instar (second instar: 15.8 to 17.7; third instar: 14.4 to 17.4). The final percent moisture content ranged from 65% to 68% for the second instars and 56% to 66% for third instars. This study demonstrates that the highest number of fungus gnat adults may be recovered from soilless growing medium (SB300 Universal Mix) treated with between 50 and 75 mL of water, thus enhancing the confidence in any data set generated when evaluating insecticides or biological control agents for control of fungus gnats.

The amphipod Hyalella azteca is widely used in ecotoxicology laboratories for the assessment of chemical risks to aquatic environments, and it is a cryptic species complex with a number of genetically distinct strains found in wild populations. While it would be valuable to note differences in contaminant sensitivity among different strains collected from various field sites, those findings would be influenced by acclimation of the populations to local conditions. In addition, potential differences in metabolism or lipid storage among different strains may confound assessment of sensitivity in unfed acute toxicity tests. In the present study, our aim was to assess whether there are genetic differences in contaminant sensitivity among three cryptic provisional species of H. azteca. Therefore, we used organisms cultured under the same conditions, assessed their ability to survive for extended periods without food, and conducted fed and unfed acute toxicity tests with two anions (nitrate and chloride) whose toxicities are not expected to be altered by the addition of food. We found that the three genetically distinct clades of H. azteca had substantially different responses to starvation, and the presence/absence of food during acute toxicity tests had a strong role in determining the relative sensitivity of the three clades. In fed tests, where starvation was no longer a potential stressor, significant differences in sensitivity were still observed among the three clades. In light of these differences in sensitivity, we suggest that ecotoxicology laboratories consider using a provisional species in toxicity tests that is a regionally appropriate surrogate.

Financial insecurity and dissatisfaction can affect the quality of family life at all income levels and across all races. Hardships resulting from financial insecurity or dissatisfaction fall most heavily upon women — directly through inferior wages and income opportunities or indirectly through abusive actions by discontented spouses. Empowering women in the financial arena can help stabilize the family and improve the quality of life for women and their dependent children.

Over the past two decades, research into the economic reasons why borrowers prepay their mortgage loans has matured into a coherent body of work that has a sound theoretical framework and consistent empirical validation. This paper summarizes progress to date in five general areas: the impact of refinancing on the cash flows and yields of mortgage-backed securities, analytical research into the value of the borrower's prepayment option, determinants of prepayment rates on mortgage pools, analyses of individual borrower behavior, and prepayment forces in the market for adjustable rate loans. Unresolved issues and suggestions for future research are also considered.

(1994). Short Selling and Common Stock Prices. Financial Analysts Journal: Vol. 50, No. 1, pp. 20-28.

This study, conducted under laboratory conditions, was designed to determine the repellent activity of 10 naturally occurring volatile alcohol constituents against adults of the fungus gnat, Bradysia sp. nr. coprophila (Lintner) (Diptera: Sciaridae). The essential oil constituents were octanoic acid, furfural, acetophenone, benzaldehyde, dimethoxybenzene, borneol, menthol, 1-octen-3-ol, and 7-hydroxycitronellol, and alpha-terpineol. alpha-Terpineol, octanoic acid and furfural were tested at several concentrations, whereas the remaining seven were tested at only one concentration. The essential oil constituents' menthol, 1-octen-3-ol, and borneol displayed the most repellent activity. The mean percentage of fungus gnat adults recovered from the test compound petri dishes associated with the three essential oil constituents was between 6 and 15% compared with between 36 and 50% for the petri dishes with distilled water. The mean +/- SEM number of fungus gnat adults present in the sample compartments associated with menthol (10.4 +/- 2.6), 1-octen-3-ol (18.8 +/- 2.4), and borneol (23.4 +/- 5.6) was statistically lower than those in the petri dishes containing distilled water (60.9 +/- 7.4, 49.8 +/- 4.0, and 79.7 +/- 13.5), respectively. Only the highest concentration of alpha-terpineol (8.0 micromol) displayed significant repellent activity against fungus gnat adults. The other essential constituents tested, including octanoic acid (all three concentrations), furfural (both concentrations), acetophenone, dimethoxybenzene, and 7-hydroxycitronellol, were not statistically different from the distilled water control. The results of this study indicate that certain essential oil constituents repel fungus gnat adults, which may be useful, from a practical standpoint, in deterring adults from laying eggs into growing media.

Both point- and nonpoint-sources of pollution have contributed to increased inorganic nitrogen concentrations in freshwater ecosystems. Although numerous studies have investigated the toxic effects of ammonia on freshwater species, relatively little work has been performed to characterize the acute toxicity of the other two common inorganic nitrogen species: nitrate and nitrite. In particular, to our knowledge, no published data exist on the toxicity of nitrate and nitrite to North American freshwater bivalves (Mollusca) or stoneflies (Insecta, Plecoptera). We conducted acute (96-h) nitrate and nitrite toxicity tests with two stonefly species (Allocapnia vivipara and Amphinemura delosa), an amphipod (Hyalella azteca), two freshwater unionid mussels (Lampsilis siliquoidea and Megalonaias nervosa), a fingernail clam (Sphaerium simile), and a pond snail (Lymnaea stagnalis). Overall, we did not observe a particularly wide degree of variation in sensitivity to nitrate, with median lethal concentrations ranging from 357 to 937 mg NO(3)-N/l; furthermore, no particular taxonomic group appeared to be more sensitive to nitrate than any other. In our nitrite tests, the two stoneflies tested were by far the most sensitive, and the three mollusks tested were the least sensitive. In contrast to what was observed in the nitrate tests, variation among species in sensitivity to nitrite spanned two orders of magnitude. Examination of the updated nitrite database, including previously published data, clearly showed that insects tended to be more sensitive than crustaceans, which were in turn more sensitive than mollusks. Although the toxic mechanism of nitrite is generally thought to be the conversion of oxygen-carrying pigments into forms that cannot carry oxygen, our observed trend in sensitivity of broad taxonomic groups, along with information on respiratory pigments in those groups, suggests that some other yet unknown mechanism may be even more important.

This paper develops a model which explains how mortgage-rate movements, transactions costs, changes in borrower income and house value, personal financial opportunities and the prepayment option embedded in fixed-rate mortgages affect a financially flexible borrower's decision to refinance an existing loan while retaining the underlying home. Broadening the focus of previous analytical work, the model explains why households with similar mortgage loans may react differently as financial market conditions change. It contains definitive empirical predictions that are supported by an analysis of a choice-based sample of individual loan transactions. Results suggest that refinancings are motivated both by movements in the level of interest rates and by borrowers' desires to alter their capital structures in the face of changing income and housing wealth.

This study examines the presence of contagion effects associated with the failure of First RepublicBank. Banks are segregated on the basis of whether their stock price reactions are likely due to industry-based information effects or contagion effects. Also considered are announcements during the same period of time associated with Third World loans. Results fail to substantiate the presence of contagion effects.

The soil bacterium Bacillus thuringiensis Berliner subsp. israelensis (Bti), the neonicotinoid insecticides dinotefuran, imidacloprid, thiamethoxam and clothianidin and the insect growth regulator pyriproxyfen were evaluated to determine their efficacy against the larval stages of the fungus gnat Bradysia sp nr. coprophila (Lintner) in the laboratory. Treatments were applied as a drench to the growing medium in polypropylene deli containers. The Bti treatments had no effect on either instar tested, whereas all the other compounds negatively affected both the second and third instars. This study demonstrates that the soil bacterium B. thuringiensis var. israelensis may not be active on these larval stages, whereas the neonicotinoid insecticides and the insect growth regulator pyriproxyfen are effective on these stages. The fact that Bti is not effective on the second and third instars of the fungus gnat means that greenhouse producers using this insecticide must make applications before fungus gnat populations build up and before overlapping generations develop.