Effect of recycled phosphogypsum and calcium aluminate cement on the strength behavior optimization of cement-treated dredged soil: A co-utilization of solid wastes.

Dredged soil and phosphogypsum (PG) are waste materials that must be treated to reduce their negative environmental effects. Guided by the concept of waste treatment, this study proposed the use of PG as a supplementary cementitious material to stabilize waste-dredged soil, and calcium aluminate cement (CAC) was selected to further improve the strength of the cement-treated dredged soil. Several laboratory tests were conducted to investigate the pH, unconfined compressive strength (UCS), and failure strain of the cement-treated soils in different proportions. Microstructural and mineralogical tests were performed to reveal the mechanisms underlying the strength improvement of PG and CAC. The results showed that both PG and CAC enhanced the strength of cement-treated dredged soil. PG provided SO2- 4 to promote the formation of ettringite (aluminum ferrite trisulfate (AFt)), whereas CAC neutralized the acidity of PG and provided reactants to the reaction system, leading to an increase in the pH and strength with an increase in the relative CAC content. Meanwhile, an exponential relationship was obtained between pH and qu. Mineralogical changes demonstrated that the major hydration products of cementitious materials, such as calcium silicate (aluminate) hydrate (C-(A)-S-H), AFt, and calcium aluminate hydrate (C-A-H), enhanced the strength by filling pores between particles and bridging soil particles. However, excess CAC content may not be favorable for the later strength formation, the relative CAC content is recommended to be in the range of 40%-60%. Compared to using sand, the construction of a square kilometer of reclamation consumed 3.5 million tons of PG, and saved 1.54 billion USD by using dredged soil as raw material. Hence, the use of PG to treat dredged soils will have great environmental sustainability, economic benefits, and engineering value.

Opistognathusctenion (Perciformes, Opistognathidae): a new jawfish from southern Japan.

Opistognathusctenionsp. nov. (Perciformes: Opistognathidae) is described on the basis of three specimens (17.3-30.6 mm in standard length) collected from the Osumi and Ryukyu islands, southern Japan in depths of 35-57 m. Although most similar to Opistognathustriops, recently described from Tonga and Vanuatu, the new species differs in mandibular pore arrangement, dorsal- and caudal-fin coloration, fewer gill rakers, and lacks blotches or stripes on the snout, suborbital region and both jaws.

Benthic impact assessment of a dredge sediment disposal in a dynamic resilient environment.

The eastern part of the Bay of Seine (English Channel) is highly impacted by harbour activities and the dumping of dredged sediment by the port authorities of Le Havre (GPMH) and Rouen (GPMR). Sediment dredged by the GPMH (2-2.5 millions of m3 per year) has been disposed at the subtidal Octeville site since 1947. Since the 2000s, mainly fine sediment (80% of fine particles <63 µm) has been disposed using alternate mosaic boxes with limited thickness (0.2 to 0.6 m per box per year), preventing the accumulation of disposed sediment in some parts of the dumping site. During the period August 2016 to September 2017, an experimental study was set up to identify the spatio-temporal changes of the macrobenthos collected at ten stations on six dates: three stations where different volumes of sediments were dumped (from 41,000 to 186,000 m3), two stations located within the Octeville site but without dumping operations during the study and five stations outside the disposal site (northern and southern zones). The Taxonomic Richness, total abundance and abundances of the polychaete Owenia fusiformis show negative correlations with the volumes of deposited sediment, whereas use of the AMBI (AZTI's Marine Biotic Index) and B2OA (Benthic Opportunist Annelids Amphipods) indices does not allow us to distinguish the impacted zone. Our study shows that the impact of dumping remains local and the benthic habitats display a high degree of resilience with rapid recovery of the community after the cessation of disturbance. Recommendations on the future long-term strategy are proposed to improve assessment and minimise the impact of dumping sediment on this benthic habitat.

A reassessment of TBT action levels for determining the fate of dredged sediments in the United Kingdom.

As part of reviewing the United Kingdom (UK) action levels (ALs) of contaminants for managing the disposal of dredged marine sediment material, tributyl tin (TBT) has been reassessed. TBT is a banned biocide capable of causing severe harm to the marine environment. Its presence is routinely screened for prior to marine disposal of dredged sediment material. Dredged sediment TBT concentrations have been studied using UK monitoring data obtained between 2000 and 2018. The changes in these TBT concentrations have guided the reassessment of ALs. Recent toxicity studies have also guided the reassessment of TBT ALs. This study, which itself forms part of a larger review by the Department for Environment, Food and Rural Affairs, has concluded that current UK TBT ALs may no longer be fit for purpose. A more environmentally protective approach for controlling release of TBT into the marine environment is recommended.

Systematic assessment of dredged sludge dewaterability improvement with different organic polymers based on analytic hierarchy process.

Organic polymeric flocculants are commonly used in improving dredged sludge dewaterability, but less attention has been paid to residual water quality. In this paper, the effects of cationic etherified starch (CS) and poly-dimethyl diallyl ammonium chloride (PDDA) on dredged sludge dewatering efficiency and residual water quality of Baiyangdian lake were comprehensively investigated and evaluated by analytic hierarchy process (AHP). The results indicated that PDDA had stronger electrical effect and flocculation performance compared with CS, resulting in more efficient dewatering performance. PDDA can reduce the pollutants of discharged residual water, while CS significantly promoted the increase of NH4+-N and NO3--N in the residual water. The increase of NH4+-N in the residual water of CS was due to the release of dredged sludge, while the increase of NO3--N was introduced by CS leaching. AHP showed that PDDA performed better in flocculation treatment of dredged sludge than other organic polymers. This work provides a method for optimization of flocculation treatment for dredged sludge dewaterability.

Sea lice Lepeophtheirus spinifer, Tuxophorus sp. and Caligus sp. infections on wild-caught queenfish Scomberoides commersonnianus from northern Australia.

Studies of ectoparasites of wild-caught queenfish Scomberoides commersonnianus from several areas in northern Australia were reviewed to investigate relationships between parasite burdens, environmental conditions and external lesions. A sample of 27 queenfish captured near a dredge spoil disposal site in Gladstone Harbour, Queensland, Australia, in January 2012 was anomalous, with a high percentage of fish (66.6%) exhibiting grossly visible skin lesions including foci of erythema and petechial haemorrhages, particularly on the pectoral girdle and ventrolateral surfaces. Microscopically, lesions comprised acute epidermal erosion, ulceration and/or perivascular dermatitis with dermal oedema and depigmentation. Skin lesions were associated with high prevalence (100%) and intensity (mean = 21.2 copepods fish-1, range 4-46) of infection by sea lice Lepeophtheirus spinifer. Only queenfish infected with >10 L. spinifer presented with skin lesions. This is the first record of L. spinifer from Australia. In contrast, grossly visible skin lesions were not reported from queenfish (n = 152) sampled from other sites in the Northern Territory and Queensland, where the sampled fish had a much lower prevalence (51.3%) and intensity (mean = 3.54, range 0-26) of copepod (L. spinifer, Caligus spp. and Tuxophorus sp.) infections. Copepods from queenfish in studies undertaken outside Gladstone Harbour exhibited an over-dispersed pattern of infection, with the vast majority (n = 137, or 90.1%) of fish infected with <5 copepods. These data demonstrate that heavy L. spinifer infections, combined with poor water quality and/or direct exposure to contaminated dredge spoil and blooms of the cyanobacterium Lyngbya majuscula, can be associated with cutaneous disease in wild-caught queenfish.

Dredging impacts on the toxicity and development of sediment quality values in a semi-arid region (Ceará state, NE Brazil).

Sediment dredging impacts coastal environments by promoting the resuspension of fine particles and remobilization of contaminants that may trigger toxic effects. In this study, we evaluated the sediment quality in harbor areas of Mucuripe bay, a semi-arid ecosystem located in Ceará state (Brazil), which is subject to dredging activities. A sampling survey was conducted right after dredging operations and data compared to another survey performed prior dredging. Sediments were analyzed for fine particles, organic carbon, nutrients, metals, hydrocarbons, and tributyltin (TBT). Toxicity of whole-sediment and liquid phase exposures were also determined. The concentrations of Cd, Cr, Cu, and Zn decreased after dredging, which was confirmed by the geoaccumulation index. Levels of TBT dropped while phosphorus, aliphatic and polycyclic aromatic hydrocarbons increased. Toxic effects persisted, indicating a post-dredging recontamination combined with other sources such as urban runoff, wastewater discharges, harbor activities, and antifouling particles. Data from Mucuripe and Pecém harbors were compiled and site-specific sediment quality values (SQVs) were developed by using multivariate methods. The threshold values proposed by our study were lower and more effective to predict toxicity compared to international guidelines, indicating levels of contamination for this tropical region in which toxic effects may occur. Considering the large geographic area with different sediment characteristics of the Brazilian coast, this study represents a significant contribution to sediment toxicity assessment of dredging activities in semi-arid environments.

Gas embolism and massive blunt force trauma to sea turtles entrained in hopper dredges in North and South Carolina, USA.

Decompression sickness (DCS) has been described mainly in loggerhead turtles Caretta caretta bycaught in trawls and gillnets. Here we present cases of gas emboli (GE) in 8 green turtles Chelonia mydas and 2 Kemp's ridleys Lepidochelys kempii entrained in hopper dredges that were working at 8.8-15.2 m depths during shipping channel maintenance or beach renourishment activities. Turtle weights ranged from 2.2 to 6.7 kg. All were found alive with blunt force injuries from passage through the dredge and were taken to rehabilitation facilities. Four green turtles died or were euthanized within 24 h. Six turtles survived. Radiographic or ultrasonographic evidence of GE was detected in 4 turtles, including 3 mortalities. Computed tomography (CT) revealed perirenal and cervical GE in 4 turtles, including 1 mortality. No GE were detected in 2 of the survivors. Upon necropsy, GE were found in mesenteric vessels, the right atrium, and kidneys. Histopathology confirmed that tissues were in a good state of preservation without evidence of bacterial overgrowth or putrefactive gas formation. Death likely resulted primarily from massive tissue trauma from the dredge, but moderate GE could have led to DCS and complicated recovery. The surviving turtles weighed less than those that did not survive. Besides hypothesized stress/exercise-induced circulatory changes of blood through the lungs and pressure reduction of forced surfacing from depth, drastic pressure change within the dredge pipes before and after the pump could contribute to GE. Hopper dredge entrainment is an additional cause of GE and potential DCS in sea turtles.

Re-imagining environmental governance: Gold dredge mining vs Territorial Health in the Colombian Amazon.

This article describes and analyses an encounter in the Colombian Amazon between Indigenous practices and arrangements to manage their environment and the conservation policies of the State. Indigenous peoples understand their world as populated by powerful human and nonhuman beings; for them, the moral duty of achieving happiness and abundance for all implies sustaining reciprocal and respectful relations with these beings (including the State). In contrast Colombian environmental policy distinguishes between nature and culture, seeking to safeguard landscapes from human interference so that natural processes can unfold unhindered. In practice these partially connected, yet incommensurable worldviews make for a 'perfect storm' - opening opportunities for illegal mining. Drawing on recent fieldwork among the Andoke, an ethnic group well acquainted with extractivism in its different historical modalities and presently affronting the fallout of gold dredge mining we narrate how a parallel, non-state governance system makes it difficult for them to care for their land and entertain mutual and respectful relations with human and nonhuman beings (which we translate as 'territorial health'). We conclude by arguing for the need to re-imagine environmental governance in ways that more closely engage with what we call pluriversal governance: a form of (environmental) governance that does ontological justice to those involved in the environmental conflict - including, crucially, Indigenous people.

Soft-bottom community responses in a marine area influenced by recurrent dumping activities and freshwater discharges.

The results of a 3 years monitoring program to assess the effects associated with recurrent dredged spoil disposal activity in a naturally stressed subtidal coastal area subjected to estuarine inputs are described. Changes observed through time in environmental and anthropogenic variables have been analyzed using cumulated sums and compared to macrobenthic community structure. Results revealed a scarce impact of the recurrent dumping activities, with faunal assemblages derived from the main "Tellina-venus community". The magnitude of estuarine influence appeared indeed greater on the soft-bottom community than the putative changes due to anthropogenic activities. Through a combination of high energetic conditions, structural changes were observed and ascribed to a flushing action of the highly channeled estuary. Finally, an exceptional flood was recorded over the monitoring period, resulting in a short-term spatial homogenization of the benthic community with an abundance burst of A. alba. Origins of this main new species are discussed.

A spatial model for the beneficial use of dredge spoil deposition: Creation and management of breeding habitat for reddish egrets in Texas.

Many species of coastal waterbirds have faced population declines in recent years as a result of loss and degradation of habitat. The creation of new habitat through strategic placement of dredge spoil can be an effective tool to mitigate habitat loss. The use of dredge spoil islands for nesting, wintering, and migratory stopover habitat by waterbirds has been documented extensively over the past several decades. Most of the reddish egret (Egretta rufescens) breeding population in the United States occurs in Texas, where it has declined by more than 30% since the 1970s. Reddish egrets breed on dredge spoil islands along the Texas coast, and the stability of breeding colonies has been variable since the 1970s. If nesting habitat is degraded or limiting in Texas, the creation of new nesting islands through strategic dredge spoil placement could benefit reddish egrets. We developed a spatially explicit prioritization model for targeted conservation of reddish egrets in the Laguna Madre, Texas, through colonial island establishment using dredge spoil. Prioritization is based on availability of foraging areas, potential competition at foraging areas, and distance of potential sites to the mainland. 'Priority areas' are potential nesting island locations that would maximize the foraging benefits for breeding reddish egrets. Model outputs show that highest priority areas in the Laguna Madre are located in the southernmost portion of the lagoon. Other priority areas are located in the lower Laguna Madre, and at the mouth of Baffin Bay. In addition, we provide a repeatable and transparent framework for the development of spatial support tools that help guide targeted placement of dredge spoil in an effort to conserve colonial waterbirds. We illustrate the model development for reddish egrets, a threatened species in Texas, however our framework can be applied to other similar species.

Selectivity of a fishing gear used in the catch of Anomalocardia flexuosa in the Northeast of Brazil / Seletividade de um petrecho de pesca utilizado na captura da Anomalocardia flexuosa no Nordeste do Brasil

ABSTRACT: A type of dredge was introduced as fishing gear along the extractive bank of Mangue Seco - PE from which the largest annual catch of Anomalocardia flexuosa in the world is extracted. This study was carried out with the objective of estimating the selectivity of the new fishing gear and quantitatively evaluating the length classes most compromised by the catches, especially considering 20 mm as the reference value. Specimens larger than this size are most likely to be mature. For the selectivity estimation, the methodology using codends (16 or 20 mm) and small meshed cover (2 mm) was used. To estimate the selectivity parameters, a logistic regression and the Bayesian approach were used. The transition between the state in which the specimen is invulnerable to the fishing gear and vulnerable occurs between 10 and 18 mm, using a 16 mm mesh, and using a 20 mm mesh, this transition is between 14 and 20 mm. Dredgers with 16 mm and 20 mm mesh compromise a large proportion of specimens smaller than 20 mm. If the intention is to protect this part of the population, measures such as total restriction of the 16 mm mesh and use of the 20 mm mesh should be necessary only in the months of less catching incidences, or increasing the mesh to 25 mm.

RESUMO: Um tipo de draga foi introduzido como arte de pesca no banco extrativista de Mangue Seco - PE de onde se extrai a maior captura anual de Anomalocardia flexuosa do mundo. Este trabalho foi realizado com objetivo de estimar a seletividade do novo petrecho de pesca e avaliar quantitativamente quais são as classes de comprimento mais penalizadas nas capturas, tendo especialmente como referencial o valor de 20 mm. Exemplares maiores que esse tamanho tem elevada probabilidade de estarem maturos. Para estimativa da seletividade foi utilizado o método com uso de saco (16 ou 20 mm) e sobresaco (2 mm). Para estimativa dos parâmetros de seletividade foi utilizada regressão logística e abordagem bayesiana. A transição entre o estado em que o exemplar é invulnerável à arte de pesca e em que o mesmo seria quase com certeza capturado ocorre para malha de 16 mm entre 10 e 18 mm, enquanto para malha de 20 mm essa transição se dá entre 14 e 20 mm. As dragas com malha de 16 e 20 mm penalizam uma proporção grande de exemplares menores que 20 mm. Se a intenção é proteger essa parcela da população, seriam necessárias medidas como a restrição total da malha de 16 mm e uso da malha de 20 mm somente nos meses de menor incidência de recrutamento, ou o aumento da malha para 25 mm.

Assessment of the physical impact of a short-term dredging operation on a semi-enclosed environment: South Euboean Gulf, Greece.

The potential influence of short-period (May-June 2012) dredging activities (for the installation of a submarine gas pipeline) on physical properties of the marine environment of two shallow-water sites in the Aliveri and Varnavas areas of South Euboean Gulf (Greece) has been evaluated. During the dredging operation in Varnavas, the induced dredge plume traveled up to ~ 750 m from the shoreline, featured by light attenuation coefficient (cp) maxima of 4.01-4.61 m-1 and suspended particulate matter (SPM) concentrations up to 6.01 mg L-1. After dredging the previous parameters reduced to the ambient seawater condition, ~ 0.45 m-1 and < 2.8 mg L-1 on average, respectively. Likewise in Aliveri, the dredging-associated sediment plume drifted offshore up to ~ 400 m from the shoreline, characterized by cp maxima of 2.11-4.86 m-1 and SPM concentrations up to 13.07 mg L-1. After the completion of the excavation and trenching activities, the cp and SPM values were restored to the pre-disturbance condition, ~ 0.6 m-1 and < 2.2 mg L-1 on average, respectively. The migration of the dredge plume in both dredging sites was accomplished through the formation of intermediate and benthic nepheloid layers, whose development and evolution were governed by seawater stratification and flow regime. The dredging-derived SPM levels appeared to increase within a distance of no more than 300 m from the shoreline (near-field zone). Based on data from the literature, this SPM enhancement together with the deposition of a post-dredging residual mud veneer in the near-field zone could deteriorate local marine biota, but in a reversible way.

Benthic marine litter in shallow fishing grounds in the NW Mediterranean Sea.

Fisheries are one of the main economic sectors affected by marine litter, which can damage gear, reduce catch, and require time to repair or clean nets. This study aims to evaluate the type and density of marine litter in two shallow fishing grounds in the NW Mediterranean Sea, both belonging to the Natura 2000 network. Moreover, it quantifies the fraction of marine litter within the total catch to help understand the potential influence of marine litter on fisheries. Two study areas were selected, one in the vicinity of urban populated areas and high navigational traffic and one in a rural site off an agricultural area. The urban area had more benthic marine litter (393 to 198 kg km-2) including clinker (residue from coal-burning steamships), fabric, plastics, and processed wood and accounting for up to 38% of the total catch. The rural area had far less marine litter (34-56 kg km-2), accounting for only 5% of the total catch. Marine litter may have potential negative effects on fisheries; thus we propose that government credit trading programs could be promoted to help recover litter from fishing catches, to reduce fishing costs and hazards to marine ecosystems.

The invasive, non-native slipper limpet Crepidula fornicata is poorly adapted to sediment burial.

The American slipper limpet Crepidula fornicata is an invasive, non-native species (INNS) abundant along the European coast. Its further distribution may be facilitated by activities such as dredging and spoil disposal, and the aim of this study was to assess whether C. fornicata is able to survive sediment burial. The slipper limpet was found attached to hard substratum in intertidal areas, but it was absent at a nearby subtidal dredge spoil site. In laboratory experiments 22% of C. fornicata emerged when buried under a 2 cm sediment-layer; only half of them survived. When buried under ≥6 cm none re-surfaced or survived. The results provided evidence that C. fornicata is poorly adapted to adjust its vertical position in sediment and is killed by sudden burial underneath 2 to 6 cm of sediment. The combined laboratory experiments and field surveys suggested that C. fornicata has limited scope to survive the dredge spoil disposal process.

From source to sink: Rare-earth elements trace the legacy of sulfuric dredge spoils on estuarine sediments.

Land disposal of dredged sulfide-rich coastal sediments generates secondary coastal acid sulfate soils (CASS), as previously reduced sulfide minerals oxidise to produce acidic drainage rich in Fe, SO42- and rare-earth elements (REEs). Few studies investigate both the source and the sink of REEs in the context of interpreting their mobilisation and potential use in tracing anthropogenic activity. Here we investigate REE signatures in estuarine sediments (and overlying surface waters) that have received acute, long-term (>15 years) acidic drainage from legacy sulfuric dredge spoils. It was found that the dredge spoil continues to act as a source of acidity (pH 3.5-5.5), Fe and REEs during development of CASS, and contains negligible acid volatile sulfide (AVS, a proxy for FeS) and relatively low concentrations of ΣREE (mean 44.5 mg/kg, range 4.1-362 mg/kg). In the receiving sediments, high AVS concentrations (mean 92.2 µmol/g, range 0.38-278 µmol/g) reflect elevated FeS content, likely due to high inputs of Fe and SO42- from the acidic drainage, and correspond with a high concentration of total S (mean 852 µmol/g, range 105-2209 µmol/g) and an accumulation of ΣREE (mean 670 mg/kg, range 19.9-1819 mg/kg). Importantly, where drain sediments that were previously enriched in highly reactive sulfidic minerals and trace elements and have become exposed to the atmosphere (e.g. Site 3) and partially oxidised, they provide a further source of acidification, remobilising the REEs to the downstream sediments. Interestingly, we also found a clear positive correlation between phosphorous and REEs both in the dredge spoil and sediment, suggesting phosphate minerals may act as a sink for REEs in CASS influenced drain sediments. This is further supported by strong positive gadolinium anomalies (1.1-1.6) and high calculated anthropogenic Gd values (12-38%), which may reflect the influence of phosphate fertiliser on this eutrophic system.

Infralittoral-sublittoral (submerged zone) macroinfauna community structure of high-impact, medium-impact and non-impact beaches on the Gulf of Cádiz coast (SW Spain). Evaluation of anthropogenic alterations: Nourishments, human impact and urbanization.

Beaches are dynamic transitional environments subject to numerous natural and anthropic alterations. In these ecosystems, the infralittoral-sublittoral macrofauna communities play a key role in the food web. The objective of this study was to compare macrofauna communities on six beaches on the Gulf of Cádiz coast, which were classified according to the anthropic alterations they support, and evaluate the influence of abiotic factors on the species distribution. Sampling was done in the infralittoral-sublittoral zone of each beach using a modified manual dredge. Five perpendicular transects of 25 m, each separated by 10 m, were performed per beach, with a total sample area of 43.75 m2 per beach. A total of 27 species were found, of which Donax trunculus, Diogenes pugilator, and Tritia grana were the most abundant. Anthropogenic effects are appreciable in the infralittoral-sublittoral although they are areas that are permanently submerged and less exposed than the intertidal. Beach nourishments carried out with large volumes of sand can alter the grain size, the most influential parameter on the distribution of the species, and consequently, affect the macrofauna community that inhabits these beaches.

Influence of Adjust Zang Dredge Meridian electroacupuncture in expression of GRP78 in sciatic nerve cells of rats with diabetic peripheral neuropathy and its neuroprotective effect / 吉林大学学报(医学版)

Oective: To investigate the expression of glucose regulating protein 78 (GRP78) in the sciatic nerve cells of the rats with diabetic peripheral neuropathy (DPN), and to elucidate the clinical significance and mechanism of Adjust Zang Dredge Meridian electroacupuncture in the treatment of DPN. Methods: A total of 86 adult male SD rats were divided into normal control group (n=5) and model group (n=81). The diabetic rat models were built through one-time injection of streptozocin (STZ), and then the diabetic rats were randomly divided into model control group (n=27), medicine intervention group (n=26), and electroacupuncture intervention group (n= 26). The rats in normal control group and model control group were fed with the maintenance feed. During the course of experiment, no special treatment was done for the rats in normal control group and model control group. The rats in drug intervention group were treated with intragastric administration of mecobalamin, 20 mg · kg-1 · d-1, once per day. The rats in electroacupuncture intervention group were treated with Adjust Zang Dredge Meridian electroacupuncture in the bilateral Feishu, Pishu, Shenshu, Hegu, Zusanli, Sanyinjiao and Taichong, once per day, 30 min per time. The thermal sensitivity value, motor nerve conduction velocity (MCV) and sensory nerve conduction velocity (SCV) of the tibial nerve of the rats in various groups were measured, the ultrastructures of sciatic nerve of the rats in various groups were observed under transmission electron microscope, the apoptotic rates of sciatic nerve cells of the rats in various groups were detected by TUNEL method, the expressions of GRP78 in sciatic nerve cells of the rats in various groups were detected by immumofluorescence, and the expression levels of GRP78 in sciatic nerve of the rats in various groups were detected by Western blotting method. Results: Compared with medicine intervention group, the thermal sensitivity value of the rats in electroacupuncture intervention group was significantly decresed (P<0. 01). Compared with model control group, the MCV and SCV of tibial nerve of the rats in medicine intervention group and electroacupuncture intervention group were increased after 12-week-intervention (P<0. 01); compared with before intervention, the MCV and SCV of tibial nerve of the rats in various groups were decreased after 12-week-intervention (P<0. 01). Under transmission electron microscope, some of the myelin sheath lamellae of sciatic nerve of the rats in model control group showed irregular membrane-like mass, and most of the thicker myelinated nerve fibers were seriously involved; the above changes were alleviated in medicine intervention group and electroacupuncture intervention group. The TUNEL assay results showed that compared with model control group, the apoptotic rates of sciatic nerve cells of the rats in medicine intervention group and electroacupuncture intervention group were significantly decreased (P < 0. 01). The Western blotting results showed that compared with model control group, the expression levels of GRP78 in sciatic nerve cells of the rats in medicine intervention group and electroacupuncture intervention group were significantly decreased (P < 0.05). Conclusion: Adjust Zang Dredge Meridian electroacupuncture can reduce the expression level of GRP78 in sciatic nerve cells of the DPN rats, inhibit the occurrence of endoplasmic reticulum stress (ERS), decrease the apoptotic rate of cells, and protect the nerves.

The application of Diffusive Gradients in Thin Films (DGT) for improved understanding of metal behaviour at marine disposal sites.

Assessment of the effects of sediment metal contamination on biological assemblages and function remains a key question in marine management, especially in relation to disposal activities. However, the appropriate description of bioavailable metal concentrations within pore-waters has rarely been reported. Here, metal behaviour and availability at contaminated dredged material disposal sites within UK waters were investigated using Diffusive Gradient in Thin films (DGT). Three stations, representing contrasting history and presence of dredge disposal were studied. Depth profiles of five metals were derived using DGT probes as well as discrete analysis of total metal concentrations from sliced cores. The metals analysed were: iron and manganese, both relevant to sediment biogeochemistry; cadmium, nickel and lead, classified as priority pollutants. DGT time-integrated labile flux profiles of the metals display behaviour consistent with increasingly reduced conditions at depth and availability to DGT (iron and manganese), subsurface peaks and a potential sedimentary source to the water column related to the disposal activity (lead and nickel) and release to pore-water linked to decomposition of enriched phytodetritus (cadmium). DGT data has the potential to improve our current understanding of metal behaviour at impacted sites and is suitable as a monitoring tool. DGT data can provide information on metal availability and fluxes within the sediment at high depth-resolution (5mm steps). Differences observed in the resulting profiles between DGT and conventional total metal analysis illustrates the significance of considering both total metals and a potentially labile fraction. The study outcomes can help to inform and improve future disposal site impact assessment, and could be complemented with techniques such as Sediment Profile Imagery for improved biologically relevance, spatial coverage and cost-effective monitoring and sampling of dredge material disposal sites. Additionally, the application of this technology could help improve correlative work on biological impacts under national and international auspices when linking biological effects to more biologically relevant metal concentrations.

Prevalence, characteristics and ecology of Vibrio vulnificus found in New Zealand shellfish.

AIMS: In New Zealand, there have been no known cases of foodborne diseases linked to Vibrio vulnificus and shellfish consumption, but two cases of wound infection have been reported. We evaluated the distribution, the effect of environmental parameters, the pheno-genotypic profile and the growth characteristics of strains isolated from shellfish. METHODS AND RESULTS: Vibrio vulnificus was present in 13·6% of Pacific oysters and not found in any dredge oyster or Greenshell(™) mussel samples. Eleven isolates belonged to biotype 1 while nine appeared to be variants of biotype 1. Nineteen isolates were genotype E (type A) and just one was genotype C (type B). Some isolates were more resistant to high salt concentrations (>30‰) than others, but not different from ATCC 27562. CONCLUSIONS: Vibrio vulnificus were low in numbers, mostly belonging to genotype E, 16S rRNA type A and biotype 1. No relationship or adaptability to high salinity was observed, but seawater temperature was a strong predictor of bacterial numbers in shellfish. SIGNIFICANCE AND IMPACT OF THE STUDY: We report, for the first time, the characterization of V. vulnificus isolated from New Zealand shellfish and its long-term distribution and prevalence. This information will help the authorities on risk assessments.