Fabrication of low-cost Mod-OA wood composite wind turbine blades

The wood composite blades were fabricated by using epoxy resin-bonded laminates of Douglas fir veneers for the leading edge spar sections and honeycomb-cored birch plywood panels for the blade trailing edge or afterbody sections. The blade was joined to the wind turbine hub assembly by epoxy resin-bonded steel load take-off studs. The wood composite blades were installed in the Mod-OA wind turbine test facility at Kahuku, Hawaii. The wood composite blades have successfully completed high power (average of 150 kW) operations for an eighteen month period (nearly 8,000 hr) before replacement with another set of wood composite blades. The original set of blades was taken out of service because of the failure of the shank on one stud. An inspection of the blades at NASA-Lewis showed that the shank failure was caused by a high stress concentration at a corrosion pit on the shank fillet radius which resulted in fatigue stresses in excess of the endurance limit

Phonon Mode Spectroscopy, Electron-Phonon Coupling and the Metal-Insulator Transition in Quasi-One-Dimensional M2Mo6Se6

We present electronic structure calculations, electrical resistivity data and the first specific heat measurements in the normal and superconducting states of quasi-one-dimensional M2Mo6Se6 (M = Tl, In, Rb). Rb2Mo6Se6 undergoes a metal-insulator transition at ~170K: electronic structure calculations indicate that this is likely to be driven by the formation of a dynamical charge density wave. However, Tl2Mo6Se6 and In2Mo6Se6 remain metallic down to low temperature, with superconducting transitions at Tc = 4.2K and 2.85K respectively. The absence of any metal-insulator transition in these materials is due to a larger in-plane bandwidth, leading to increased inter-chain hopping which suppresses the density wave instability. Electronic heat capacity data for the superconducting compounds reveal an exceptionally low density of states DEF = 0.055 states eV^-1 atom^-1, with BCS fits showing 2Delta/kBTc >= 5 for Tl2Mo6Se6 and 3.5 for In2Mo6Se6. Modelling the lattice specific heat with a set of Einstein modes, we obtain the approximate phonon density of states F(w). Deconvolving the resistivity for the two superconductors then yields their electron-phonon transport coupling function a^2F(w). In Tl2Mo6Se6 and In2Mo6Se6, F(w) is dominated by an optical "guest ion" mode at ~5meV and a set of acoustic modes from ~10-30meV. Rb2Mo6Se6 exhibits a similar spectrum; however, the optical phonon has a lower intensity and is shifted to ~8meV. Electrons in Tl2Mo6Se6 couple strongly to both sets of modes, whereas In2Mo6Se6 only displays significant coupling in the 10-18meV range. Although pairing is clearly not mediated by the guest ion phonon, we believe it has a beneficial effect on superconductivity in Tl2Mo6Se6, given its extraordinarily large coupling strength and higher Tc compared to In2Mo6Se6.Comment: 16 pages, 13 figure

Superconducting transitions of intrinsic arrays of weakly coupled one-dimensional superconducting chains: the case of the extreme quasi-1D superconductor Tl(2)Mo(6)Se(6)

International audienceTl(2)Mo(6)Se(6) represents a model system for quasi-one-dimensional (quasi-1D) superconductors. We investigate its superconducting transition in detail by means of electrical transport experiments on high-quality single crystalline samples with onset T(c) = 6.8 K. Our measurements indicate a highly complex superconducting transition that occurs in different stages, with a characteristic bump in the resistivity and distinct plateau structures in the supercurrent gap imaged by V-I curves. We interpret these features as fingerprints of the gradual establishment of global phase coherence in an array of weakly coupled parallel 1D superconducting bundles. In this way, we demonstrate that superconducting Tl(2)Mo(6)Se(6) behaves like an intrinsic array of proximity or Josephson junctions, undergoing a complex superconducting phase-ordering transition at 4.5 K that shows many similarities to the Berezinskii-Kosterlitz-Thouless transition

Multi-band Superconductivity in the Chevrel Phases SnMo6S8 and PbMo6S8

Sub-Kelvin scanning tunnelling spectroscopy in the Chevrel Phases SnMo6S8 and PbMo6S8 reveals two distinct superconducting gaps with Delta_1 = 3 meV, Delta_2 ~ 1.0 meV and Delta_1 = 3.1 meV, Delta_2 ~ 1.4 meV respectively. The gap distribution is strongly anisotropic, with Delta_2 predominantly seen when scanning across unit-cell steps on the (001) sample surface. The spectra are well-fitted by an anisotropic two-band BCS s-wave gap function. Our spectroscopic data are confirmed by electronic heat capacity measurements which also provide evidence for a twin-gap scenario.Comment: 5 pages, 4 figure

Bridging Time Scales in Cellular Decision Making with a Stochastic Bistable Switch

Cellular transformations which involve a significant phenotypical change of the cell's state use bistable biochemical switches as underlying decision systems. In this work, we aim at linking cellular decisions taking place on a time scale of years to decades with the biochemical dynamics in signal transduction and gene regulation, occuring on a time scale of minutes to hours. We show that a stochastic bistable switch forms a viable biochemical mechanism to implement decision processes on long time scales. As a case study, the mechanism is applied to model the initiation of follicle growth in mammalian ovaries, where the physiological time scale of follicle pool depletion is on the order of the organism's lifespan. We construct a simple mathematical model for this process based on experimental evidence for the involved genetic mechanisms. Despite the underlying stochasticity, the proposed mechanism turns out to yield reliable behavior in large populations of cells subject to the considered decision process. Our model explains how the physiological time constant may emerge from the intrinsic stochasticity of the underlying gene regulatory network. Apart from ovarian follicles, the proposed mechanism may also be of relevance for other physiological systems where cells take binary decisions over a long time scale.Comment: 14 pages, 4 figure

Multicentre prospective evaluation of histological and molecular criterion for diagnosis of prosthetic-joint infection

Objectives: This multicenter prospective study was performed to assess the contribution of broad range PCR diagnosis in prosthetic-joint infection (PJI). Methods: Adult patients treated for PJI at 7 centers were included between December 2010 and March 2012. Six per-operative samples were obtained for each patient, 5 for conventional cultures and 16S rRNA gene real-time PCR followed by sequencing, and 1 for histopathological classification according to Morawietz. Cultures and PCR were performed in a highly standardized manner, with 3 quality controls of PCR analyses. An infection was considered as proved (3 criteria: per-operative, bacteriological and histological), probable (clinical or bacteriological criterium), or excluded (no criterium). Molecular criterium for predicting PJI was determined using the bacteriological one as reference (>=1 positive sample for virulent organism, and >=3 positive samples for coagulase-negative staphylococci (CoNS) and P. acnes). Results: 299 patients were included, 264 with suspicion of sepsis (S) and 35 as controls (C). The 264 S presented with acute (19%), or chronic suspicion of PJI (81%). Infection was proved or probable in 212/264 S (80%), with the bacteriological criterium in 189/212 S (89%). Out of these, 156 (83%) had monomicrobial and 33 (17%) polymicrobial infections. The isolated pathogens were S. aureus (40%), CoNS (25%), streptococci (14%), Gram-Negative rods (10%), and anaerobes 8%. Histology results were not available for 55 patients, leaving 244 patients available for analysis. Histological findings of infection (Morawietz types II or III) were present in 128/169 (76%) proved or probable infections, in 3 patients without any other criterium, and were absent in excluded infections (n=42) and controls (n=29). PCR results were not analysable for 32 patients (S=28, C=4), leaving 267 patients (S=236, C=31) available for analysis. Molecular criterium of infection was present in 63/68 (93%) proved infections, 83/124 (67%) probable infections, 3/42 excluded infections, 0/2 histological criterium alone and 2/31 controls. Molecular criterium of infection was absent in 34/189 (18%) culture-positive S, and present in 8/23 culture-negative S (8 patients treated with antibiotics). Conclusions: According to this multicenter prospective study, 16S rRNA gene real-time PCR is less susceptible than culture for diagnosis of PJI. Molecular analysis could be recommended in culture-negative patients who were receiving antibiotics

New insights into the early evolution of horizontal spiral trace fossils and the age of the Brioverian series (Ediacaran-Cambrian) in Brittany, NW France

In northwestern France, the Brioverian series is a thick siliciclastic succession deposited during the Cadomian cycle (c. 750-540 Ma). In the uppermost Brioverian beds, previous studies unravelled an assemblage dominated by simple horizontal trace fossils associated with microbially stabilized surfaces. Here, we report Spirodesmos trace fossils - one-way, irregular and regular horizontal spirals - from Crozon (Finistère, Brittany), Montfort-sur-Meu and St-Gonlay (Ille-et-Vilaine, Brittany). After reviewing the literature on horizontal spiral trace fossils, an Ediacaran-Fortunian Spirodesmos pool is identified from marginal-marine to shelf settings, while an Ordovician-Recent trend formed in the deep-marine realm. These results suggest that an onshore-offshore migration in Spirodesmos took place during Ediacaran-Fortunian to Ordovician time, similar to what happened in graphoglyptids. In addition, the age of the uppermost Brioverian beds (Ediacaran or early Cambrian) is still a pending question. Here, we report two new U-Pb detrital zircon datings from sandstone samples in St-Gonlay, giving maximum deposition ages of 551 ± 7 Ma and 540 ± 5 Ma. Although these results do not discard an Ediacaran age for the uppermost Brioverian beds, a Fortunian age is envisioned because the new dating corroborates previous dating from Brittany, Mayenne and Normandy. However, the intervals of error of the radiometric dating, and the dominance of non-penetrative trace fossils associated with matgrounds (an ecology more typical of the Ediacaran Period), do not allow definitive conclusions on the age of the uppermost Brioverian beds

Evaluation of 16S rRNA gene PCR sensitivity and specificity for diagnosis of prosthetic joint infection: a prospective multicenter cross-sectional study

There is no standard method for the diagnosis of prosthetic joint infection (PJI). The contribution of 16S rRNA gene PCR sequencing on a routine basis remains to be defined. We performed a prospective multicenter study to assess the contributions of 16S rRNA gene assays in PJI diagnosis. Over a 2-year period, all patients suspected to have PJIs and a few uninfected patients undergoing primary arthroplasty (control group) were included. Five perioperative samples per patient were collected for culture and 16S rRNA gene PCR sequencing and one for histological examination. Three multicenter quality control assays were performed with both DNA extracts and crushed samples. The diagnosis of PJI was based on clinical, bacteriological, and histological criteria, according to Infectious Diseases Society of America guidelines. A molecular diagnosis was modeled on the bacteriological criterion (≥ 1 positive sample for strict pathogens and ≥ 2 for commensal skin flora). Molecular data were analyzed according to the diagnosis of PJI. Between December 2010 and March 2012, 264 suspected cases of PJI and 35 control cases were included. PJI was confirmed in 215/264 suspected cases, 192 (89%) with a bacteriological criterion. The PJIs were monomicrobial (163 cases [85%]; staphylococci, n = 108; streptococci, n = 22; Gram-negative bacilli, n = 16; anaerobes, n = 13; others, n = 4) or polymicrobial (29 cases [15%]). The molecular diagnosis was positive in 151/215 confirmed cases of PJI (143 cases with bacteriological PJI documentation and 8 treated cases without bacteriological documentation) and in 2/49 cases without confirmed PJI (sensitivity, 73.3%; specificity, 95.5%). The 16S rRNA gene PCR assay showed a lack of sensitivity in the diagnosis of PJI on a multicenter routine basis

The contributory role of autism symptomology in child pornography offending : why there is an urgent need for empirical research in this area

Purpose As recently highlighted by Creaby-Attwood and Allely (2017) it is crucial that the possible innate vulnerabilities that contributed to sexual offending behaviour in an individual with an autism spectrum disorder (ASD) are taken into consideration for the application of a diversion program to avoid the stigma of a criminal conviction or during sentencing for a non-custodial outcome. Specifically, in those defendants with a diagnosis of what used to be referred to as Asperger's Syndrome (AS) and now is recognised as an ASD and who are charged and convicted of a non-contact sexual offence, education and mental health intervention will best serve the interests of justice. Design/methodology/approach This paper focuses on one particular type of sexual offending behaviour, namely, possession of child pornography. A systematic PRISMA review was conducted. Findings The authors linked examples of child pornography in the research literature to the ASD symptomology and describe how the symptomology explains such behaviour as not reflecting actual sexual deviance. Originality/value Downloading and viewing of child pornography by individuals with ASD has received relatively little research outside the mental health field. This review is of particular importance to those in the criminal justice system who may not have much knowledge and understanding of ASD. It is suggested that diversion programmes and mental health courts should be set up for this particular population charged with this particular crime in mind so that the necessary treatment/intervention/support and care can be given to this particular group. Keywords: Autism Spectrum Disorder; Asperger’s syndrome; child pornography; child exploitative material; pretrial diversio

CONCEPTT: Continuous Glucose Monitoring in Women with Type 1 Diabetes in Pregnancy Trial: A multi-center, multi-national, randomized controlled trial - Study protocol.

BACKGROUND: Women with type 1 diabetes strive for optimal glycemic control before and during pregnancy to avoid adverse obstetric and perinatal outcomes. For most women, optimal glycemic control is challenging to achieve and maintain. The aim of this study is to determine whether the use of real-time continuous glucose monitoring (RT-CGM) will improve glycemic control in women with type 1 diabetes who are pregnant or planning pregnancy. METHODS/DESIGN: A multi-center, open label, randomized, controlled trial of women with type 1 diabetes who are either planning pregnancy with an HbA1c of 7.0 % to ≤10.0 % (53 to ≤ 86 mmol/mol) or are in early pregnancy (<13 weeks 6 days) with an HbA1c of 6.5 % to ≤10.0 % (48 to ≤ 86 mmol/mol). Participants will be randomized to either RT-CGM alongside conventional intermittent home glucose monitoring (HGM), or HGM alone. Eligible women will wear a CGM which does not display the glucose result for 6 days during the run-in phase. To be eligible for randomization, a minimum of 4 HGM measurements per day and a minimum of 96 hours total with 24 hours overnight (11 pm-7 am) of CGM glucose values are required. Those meeting these criteria are randomized to RT- CGM or HGM. A total of 324 women will be recruited (110 planning pregnancy, 214 pregnant). This takes into account 15 and 20 % attrition rates for the planning pregnancy and pregnant cohorts and will detect a clinically relevant 0.5 % difference between groups at 90 % power with 5 % significance. Randomization will stratify for type of insulin treatment (pump or multiple daily injections) and baseline HbA1c. Analyses will be performed according to intention to treat. The primary outcome is the change in glycemic control as measured by HbA1c from baseline to 24 weeks or conception in women planning pregnancy, and from baseline to 34 weeks gestation during pregnancy. Secondary outcomes include maternal hypoglycemia, CGM time in, above and below target (3.5-7.8 mmol/l), glucose variability measures, maternal and neonatal outcomes. DISCUSSION: This will be the first international multicenter randomized controlled trial to evaluate the impact of RT- CGM before and during pregnancy in women with type 1 diabetes. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01788527 Registration Date: December 19, 2012