HEALTH COSTS AND EXTERNALITIES OF PESTICIDE USE IN LOCUST AND GRASSHOPPER CONTROL IN THE SAHEL

To evaluate the economic cost of classical chemical control of locusts, externalities of chemical pesticides in the Sahel are estimated through a farmer survey. The costs of human health, losses in domestic animals and of destroying obsolete pesticides are estimated at $4 per treated ha for chemical control.Environmental Economics and Policy, Health Economics and Policy,

Ecology and biogeography of free-living nematodes associated with chemosynthetic environments in the deep sea: A review

Background: Here, insight is provided into the present knowledge on free-living nematodes associated with chemosynthetic environments in the deep sea. It was investigated if the same trends of high standing stock, low diversity, and the dominance of a specialized fauna, as observed for macro-invertebrates, are also present in the nematodes in both vents and seeps.Methodology: This review is based on existing literature, in combination with integrated analysis of datasets, obtained through the Census of Marine Life program on Biogeography of Deep-Water Chemosynthetic Ecosystems (ChEss).Findings: Nematodes are often thriving in the sulphidic sediments of deep cold seeps, with standing stock values ocassionaly exceeding largely the numbers at background sites. Vents seem not characterized by elevated densities. Both chemosynthetic driven ecosystems are showing low nematode diversity, and high dominance of single species. Genera richness seems inversely correlated to vent and seep fluid emissions, associated with distinct habitat types. Deep-sea cold seeps and hydrothermal vents are, however, highly dissimilar in terms of community composition and dominant taxa. There is no unique affinity of particular nematode taxa with seeps or vents.Conclusions: It seems that shallow water relatives, rather than typical deep-sea taxa, have successfully colonized the reduced sediments of seeps at large water depth. For vents, the taxonomic similarity with adjacent regular sediments is much higher, supporting rather the importance of local adaptation, than that of long distance distribution. Likely the ephemeral nature of vents, its long distance offshore and the absence of pelagic transport mechanisms, have prevented so far the establishment of a successful and typical vent nematode fauna. Some future perspectives in meiofauna research are provided in order to get a more integrated picture of vent and seep biological processes, including all components of the marine ecosystem

Population genetic structure in <i>Sabatieria</i> (Nematoda) reveals intermediary gene flow and admixture between distant cold seeps from the Mediterranean Sea

BackgroundThere is a general lack of information on the dispersal and genetic structuring for populations of small-sized deep-water taxa, including free-living nematodes which inhabit and dominate the seafloor sediments. This is also true for unique and scattered deep-sea habitats such as cold seeps. Given the limited dispersal capacity of marine nematodes, genetic differentiation between such geographically isolated habitat patches is expected to be high. Against this background, we examined genetic variation in both mitochondrial (COI) and nuclear (18S and 28S ribosomal) DNA markers of 333 individuals of the genus Sabatieria, abundantly present in reduced cold-seep sediments. Samples originated from four Eastern Mediterranean cold seeps, separated by hundreds of kilometers, and one seep in the Southeast Atlantic.ResultsIndividuals from the Mediterranean and Atlantic were divided into two separate but closely-related species clades. Within the Eastern Mediterranean, all specimens belonged to a single species, but with a strong population genetic structure (ΦST = 0.149). The haplotype network of COI contained 19 haplotypes with the most abundant haplotype (52% of the specimens) shared between all four seeps. The number of private haplotypes was high (15), but the number of mutations between haplotypes was low (1–8). These results indicate intermediary gene flow among the Mediterranean Sabatieria populations with no evidence of long-term barriers to gene flow.ConclusionsThe presence of shared haplotypes and multiple admixture events indicate that Sabatieria populations from disjunct cold seeps are not completely isolated, with gene flow most likely facilitated through water current transportation of individuals and/or eggs. Genetic structure and molecular diversity indices are comparable to those of epiphytic shallow-water marine nematodes, while no evidence of sympatric cryptic species was found for the cold-seep Sabatieria

Management of intractable bladder neck strictures following radical prostatectomy using the Memokath®045 stent

The incidence of vesicourethral anastomotic stenosis (VUAS) post radical prostatectomy varies from 1 to 26%. Current treatment can be challenging and includes a variety of different procedures. These range from endoscopic dilations to bladder neck reconstruction to urinary diversion. We investigated a 2-stage endoscopic treatment, using the thermo-expandable Memokath®045 bladder neck stent to manage patients with VUAS post radical prostatectomy. We retrospectively reviewed 30 patients, between 2013 and 2017, who underwent a Memokath®045 stent insertion following failed primary treatment (dilation and clean intermittent catheterisation) for VUAS. The mean interval time between prostatectomy and Memokath®045 stent insertion was 13 months. The mean follow-up time was 3.6 years with all patients having a minimum of 12-month follow-up. All patients had two previous attempts at endoscopic dilatation with or without incision and a trial of clean intermittent catheterisation. During stage 1, the anastomotic stricture is dilated/incised to diameter of 30 Fr, the stricture length is measured, and a catheter is left in situ. One to 2 weeks later, post haemostasis and healing, an appropriately sized Memokath®045 stent is inserted. The stent is then removed 1-year post-op. Our series of patients had a median age of 62 (54–72). Most patients (26) had a robot-assisted radical prostatectomy (RARP) or salvage procedure. Results showed improvement in IPSS scores, IPSS quality of life scores, Qmax and PVR after the Memokath®045 stent was removed compared to pre-operation. With a minimum of 12 months post stent removal, 93% of patients were fully continent, whilst 7% of patients were socially continent. 2 (7%) patients had their stents removed and not replaced due to re-stricturing and stone formation. However, no urinary tract infections, stricture recurrence or urinary retention was observed in the rest of the cohort (93%). Overall, the Memokath®045 stent was successful in treating 93% of our patients with VUAS. Our series had minimal complications that were managed with conservative measures and in three patients’ re-operation was needed. In conclusion, the Memokath®045 stent is a minimally invasive technique with faster recovery time compared to other techniques such as bladder neck reconstruction or urinary diversion. Additionally, it provides superior patency results compared to other techniques such as bladder neck incision and injection of Mitomycin C. Therefore, this management option should be considered in the management of VUAS

A three-dimensional geometric morphometric study of the effects of erosion on the morphologies of modern and prehistoric footprints.

Introduction: Fossilised footprints have been discovered all over the world and can provide information regarding the foot size and subsequent body size estimates of the track makers or an insight into the kinematics of the foot/lower limb. After exposure, these fossils rapidly erode. It is predicted that footprint morphology is compromised after creation, prior to fossilisation and that erosion after exposure will affect the morphology of a footprint after exposure. To date, no studies have assessed if degradation prior to fossilisation and/or after fossilisation, and subsequent exposure, affects the morphology of the print, thereby affecting any measurements taken. This study aims to quantify these pre- and post-erosional processes. Materials and methods: A set of experimentally generated footprints were created to test the effects of degradation of footprint morphology prior to fossilisation. In addition, Holocene footprints were recorded at Formby Point, Sefton, UK. In just over a week tidal action had completely eroded the Holocene beds. Photogrammetry was applied to the experimental human footprints and a selection of Holocene human and animal footprints. Three-dimensional Geometric Morphometric methods were utilised to estimate differences in shape and size. Results: Results from the experimental footprints indicate that weather action affects the size and shape of a footprint prior to fossilisation. When the weather was dry, footprint shape and size showed little difference for two weeks, but rainfall caused significant changes. The Holocene footprints show that after fossilisation and exposure to coastal erosion, footprint rigidity is highly compromised. The human footprint borders progressively recede, increasing length and width each day. Footprint depth, often used to inform upon speed and kinematics, varied considerably in one week. Some regions becoming shallower, others increasing in depth. Similar results were found for the animal footprints, but with less significant changes in shape and size determined. Conclusion: Observed significant differences in measurements result in problems for predicting stature, mass, sex, and kinematic analyses. This warrants caution when making interpretations from fossilised footprints. Rapid recording of fossilised prints from first exposure and assessing pre-fossilisation processed are necessities when recording footprint surfaces

Management of intractable bladder neck strictures following radical prostatectomy using the Memokath\uae045 stent

The incidence of vesicourethral anastomotic stenosis (VUAS) post radical prostatectomy varies from 1 to 26%. Current treatment can be challenging and includes a variety of different procedures. These range from endoscopic dilations to bladder neck reconstruction to urinary diversion. We investigated a 2-stage endoscopic treatment, using the thermo-expandable Memokath\uae045 bladder neck stent to manage patients with VUAS post radical prostatectomy. We retrospectively reviewed 30 patients, between 2013 and 2017, who underwent a Memokath\uae045 stent insertion following failed primary treatment (dilation and clean intermittent catheterisation) for VUAS. The mean interval time between prostatectomy and Memokath\uae045 stent insertion was 13\ua0months. The mean follow-up time was 3.6\ua0years with all patients having a minimum of 12-month follow-up. All patients had two previous attempts at endoscopic dilatation with or without incision and a trial of clean intermittent catheterisation. During stage 1, the anastomotic stricture is dilated/incised to diameter of 30\ua0Fr, the stricture length is measured, and a catheter is left in situ. One to 2\ua0weeks later, post haemostasis and healing, an appropriately sized Memokath\uae045 stent is inserted. The stent is then removed 1-year post-op. Our series of patients had a median age of 62 (54\u201372). Most patients (26) had a robot-assisted radical prostatectomy (RARP) or salvage procedure. Results showed improvement in IPSS scores, IPSS quality of life scores, Qmax and PVR after the Memokath\uae045 stent was removed compared to pre-operation. With a minimum of 12\ua0months post stent removal, 93% of patients were fully continent, whilst 7% of patients were socially continent. 2 (7%) patients had their stents removed and not replaced due to re-stricturing and stone formation. However, no urinary tract infections, stricture recurrence or urinary retention was observed in the rest of the cohort (93%). Overall, the Memokath\uae045 stent was successful in treating 93% of our patients with VUAS. Our series had minimal complications that were managed with conservative measures and in three patients\u2019 re-operation was needed. In conclusion, the Memokath\uae045 stent is a minimally invasive technique with faster recovery time compared to other techniques such as bladder neck reconstruction or urinary diversion. Additionally, it provides superior patency results compared to other techniques such as bladder neck incision and injection of Mitomycin C. Therefore, this management option should be considered in the management of VUAS