Evidence for a magnesium-insensitive membrane resistance increase during NMDA-induced depolarizations in rat neocortical neurons in vitro

The responses of rat neocortical neurons in vitro to iontophoretically applied N-methyl-d-aspartate (NMDA) were investigated by means of intracellular recording in the presence and absence of extracellular magnesium ions (Mg2+). At Mg2+-concentrations of 1.3 mM the neurons responded with a depolarization accompanied by an increase in membrane resistance. Upon removal of Mg2+ the NMDA-induced depolarization was markedly potentiated. However, even in neurons recorded from slices which were incubated in a Mg2+-free solution for 3–7 h, the NMDA response was still associated with a resistance increase, suggesting that the voltage-dependence of the NMDA-activated conductance is not exclusively determined by Mg2+

Sensitivity of Ti-6Al-4V components to oxidation during out of chamber wire arc additive layer manufacturing (WAALM)

Wire Arc Additive Manufacturing is an innovative manufacturing process with great potential for production of large ribbed titanium aerospace components. Based on well-established and trusted welding technology, the process is extremely affordable, characterized by its potential for high deposition rates and free of the limitations associated with presently utilized additive manufacturing processes. However, given titanium’s extreme reactivity at high temperatures, an ongoing challenge is to prevent atmospheric contamination during out-of-chamber material deposition. This is especially important during additive layer manufacturing, as surface oxidation formed from previous layers is readily absorbed during deposition of subsequent layers. This engineering thesis explores the overall sensitivity of Ti-6Al-4V components to oxidation contamination during out-of-chamber Wire Arc Additive Layer Manufacturing (WAALM). Several sample conditions were produced through various argon trailing shield configurations and the changes in alloying element chemistry and mechanical properties evaluated. Other techniques, such as sand blasting to reduce re-inclusion of surface oxidation, were also investigated. This work aids in determining acceptable levels of surface oxidation during out-of-chamber wire arc additive manufacturing. Irrespective of the level of surface oxidation, no significant difference in chemical or mechanical properties were observed between each sample condition. Overall, more focus needs to be placed on providing quality wire feedstock and ensuring shielding at the melt pool, as opposed to qualitative analysis of surface oxidation

Appearances can be deceiving: How naturalistic changes to target appearance impact on lineup-based decision-making

The present study examined the influence of appearance, procedure and position on identification decisions, post-decisional confidence ratings and estimates of discrimination and confidence-specific accuracy. Regarding appearance, the study examined the combined influence of three naturalistic changes that occur day-to-day (i.e. a reduction in cranial hair length, the removal of stubble, and a change of clothing), two of which have not been considered before in a lineup-decision context. Participants (N = 350) completed four experimental lineups which involved: viewing a target person, completing a brief distractor task, and making an identification decision and a post-decisional confidence rating from a photographic lineup. Participants were randomly allocated to complete simultaneous or sequential lineups, with appearance (no change, change), position (early, late) and target (present, absent) systematically varied across the four trials. Appearance affected all dependent measures and was particularly influential in target-present lineups. Naturalistic changes to target appearance reliably decreased correct identification rates, confidence in correct identifications, discrimination accuracy, and confidence-specific accuracy. Procedure and position, by contrast, had a more limited impact. Of concern for the criminal justice system, neither procedure nor position manipulations offset any reductions in lineup-decision accuracy when target appearance changed

On Differences of Zeta Values

Finite differences of values of the Riemann zeta function at the integers are explored. Such quantities, which occur as coefficients in Newton series representations, have surfaced in works of Maslanka, Coffey, Baez-Duarte, Voros and others. We apply the theory of Norlund-Rice integrals in conjunction with the saddle point method and derive precise asymptotic estimates. The method extends to Dirichlet L-functions and our estimates appear to be partly related to earlier investigations surrounding Li's criterion for the Riemann hypothesis.Comment: 18 page

Variation in incidence of breast, lung and cervical cancer and malignant melanoma of skin by socioeconomic group in England

BACKGROUND: Cancer incidence varies by socioeconomic group and these variations have been linked with environmental and lifestyle factors, differences in access to health care and health seeking behaviour. Socioeconomic variations in cancer incidence by region and age are less clearly understood but they are crucial for targeting prevention measures and health care commissioning. METHODS: Data were obtained from all eight English cancer registries for patients diagnosed between 1998 and 2003, for all invasive cases of female breast cancer (ICD-10 code C50), lung cancer (ICD-10 codes C33-C34), cervical cancer (ICD-10 code C53), and malignant melanoma of the skin (ICD-10 code C43). Socioeconomic status was assigned to each patient based on their postcode of residence at diagnosis, using the income domain of the Index of Multiple Deprivation 2004. We analysed the socioeconomic variations in the incidence of breast, lung and cervical cancer and malignant melanoma of the skin for England, and regionally and by age. RESULTS: Incidence was highest for the most deprived patients for lung cancer and cervical cancer, whilst the opposite was observed for malignant melanoma and breast cancer. The difference in incidence between the most and the least deprived groups was higher for lung cancer patients aged under 65 at diagnosis than those over 65 at diagnosis, which may indicate a cohort effect. There were regional differences in the socioeconomic gradients with the gap being widest for lung and cervical cancer in the North (North East, North West and Yorkshire and Humberside) and for malignant melanoma in the East and South West. There were only modest variations in breast cancer incidence by region. If the incidence of lung and cervical cancer were decreased to that of the least deprived group it would prevent 36% of lung cancer cases in men, 38% of lung cancer cases in women and 28% of cervical cancer cases. Incidence of breast cancer and melanoma was highest in the least deprived group, therefore if all socioeconomic groups had incidence rates similar to the least deprived group it is estimated that the number of cases would increase by 7% for breast cancer, 27% for melanoma in men and 29% for melanoma in women. CONCLUSION: National comparison of socioeconomic variations in cancer incidence by region and age can provide an unbiased basis for public health prevention and health commissioning. Decreasing inequalities in incidence requires the integration of information on risk factors, incidence and projected incidence but targeted public health interventions could help to reduce regional inequalities in incidence and reduce the future cancer burden

Ganglioside Alters Phospholipase Trafficking, Inhibits NF-κB Assembly, and Protects Tight Junction Integrity

Background and Aims: Dietary gangliosides are present in human milk and consumed in low amounts from organ meats. Clinical and animal studies indicate that dietary gangliosides attenuate signaling processes that are a hallmark of inflammatory bowel disease (IBD). Gangliosides decrease pro-inflammatory markers, improve intestinal permeability, and reduce symptoms characteristic in patients with IBD. The objective of this study was to examine mechanisms by which dietary gangliosides exert beneficial effects on intestinal health. Methods: Studies were conducted in vitro using CaCo-2 intestinal epithelial cells. Gangliosides were extracted from milk powder and incubated with differentiated CaCo-2 cells after exposure to pro-inflammatory stimuli. Gut barrier integrity was assessed by electron microscopy, epithelial barrier function was examined by measuring transepithelial electric resistance, and content of HBD-2, IL-23, NF-κB, and sPLA2 was assessed by ELISA. Results: Ganglioside attenuated the decrease in integrity of tight junctions induced by pro-inflammatory stimuli and improved epithelial barrier function (P \u3c 0.05). Ganglioside decreased the basolateral secretion of sPLA2 (P ≤ 0.05), lowered HBD-2 and IL-23 levels (P ≤ 0.05), and inhibited NF-κB activation (P ≤ 0.05). Conclusions: In summary, the present study indicates that ganglioside GD3 improves intestinal integrity by altering sPLA2 trafficking, and the production of pro-inflammatory mediators is mitigated by decreasing assembly of the NF-κB complex. Dietary gangliosides may have promising potential beneficial effects in IBD as decreased inflammatory signaling, improved intestinal integrity, and maintenance of epithelial barrier function have been demonstrated in vitro

Nanofabrication by self-assembly

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Influence of association state and DNA binding on the O2-reactivity of [4Fe-4S] fumarate and nitrate reduction (FNR) regulator

The fumarate and nitrate reduction (FNR) regulator is the master switch for the transition between anaerobic and aerobic respiration in Escherichia coli. Reaction of dimeric [4Fe-4S] FNR with O2 results in conversion of the cluster into a [2Fe-2S] form, via a [3Fe-4S] intermediate, leading to the loss of DNA binding through dissociation of the dimer into monomers. In the present paper, we report studies of two previously identified variants of FNR, D154A and I151A, in which the form of the cluster is decoupled from the association state. In vivo studies of permanently dimeric D154A FNR show that DNA binding does not affect the rate of cluster incorporation into the apoprotein or the rate of O2-mediated cluster loss. In vitro studies show that O2-mediated cluster conversion for D154A and the permanent monomer I151A FNR is the same as in wild-type FNR, but with altered kinetics. Decoupling leads to an increase in the rate of the [3Fe-4S]1+ into [2Fe-2S]2+ conversion step, consistent with the suggestion that this step drives association state changes in the wild-type protein. We have also shown that DNA-bound FNR reacts more rapidly with O2 than FNR free in solution, implying that transcriptionally active FNR is the preferred target for reaction with O2

Feeding the world\u27s largest fish: highly variable whale shark residency patterns at a provisioning site in the Philippines

Provisioning wildlife for tourism is a controversial yet widespread practice. We analysed the residency patterns of juvenile whale sharks (Rhincodon typus) in Oslob, Philippines, where provisioning has facilitated a large shark-watching operation since 2011. We identified 208 individual sharks over three years, with an average of 18.6 (s.d. = 7.8, range = 6–43) individuals sighted per week. Weekly shark abundance varied seasonally and peak-season abundance (approx. May–November) increased across years. Whale sharks displayed diverse individual site visitation patterns ranging from a single visit to sporadic visits, seasonal residency and year-round residency. Nine individuals became year-round residents, which represents a clear response to provisioning. The timing of the seasonal peak at Oslob did not align with known non-provisioned seasonal aggregations elsewhere in the Philippines, which could suggest that seasonal residents at Oslob exploit this food source when prey availability at alternative sites is low. Since prolonged residency equates to less time foraging naturally, provisioning could influence foraging success, alter distributions and lead to dependency in later life stages. Such impacts must be carefully weighed against the benefits of provisioning (i.e. tourism revenue in a remote community) to facilitate informed management decisions

Does shear wave ultrasound independently predict axillary lymph node metastasis in women with invasive breast cancer?

Shear wave elastography (SWE) shows promise as an adjunct to greyscale ultrasound examination in assessing breast masses. In breast cancer, higher lesion stiffness on SWE has been shown to be associated with features of poor prognosis. The purpose of this study was to assess whether lesion stiffness at SWE is an independent predictor of lymph node involvement. Patients with invasive breast cancer treated by primary surgery, who had undergone SWE examination were eligible. Data were retrospectively analysed from 396 consecutive patients. The mean stiffness values were obtained using the Aixplorer(®) ultrasound machine from SuperSonic Imagine Ltd. Measurements were taken from a region of interest positioned over the stiffest part of the abnormality. The average of the mean stiffness value obtained from each of two orthogonal image planes was used for analysis. Associations between lymph node involvement and mean lesion stiffness, invasive cancer size, histologic grade, tumour type, ER expression, HER-2 status and vascular invasion were assessed using univariate and multivariate logistic regression. At univariate analysis, invasive size, histologic grade, HER-2 status, vascular invasion, tumour type and mean stiffness were significantly associated with nodal involvement. Nodal involvement rates ranged from 7 % for tumours with mean stiffness <50 kPa to 41 % for tumours with a mean stiffness of >150 kPa. At multivariate analysis, invasive size, tumour type, vascular invasion, and mean stiffness maintained independent significance. Mean stiffness at SWE is an independent predictor of lymph node metastasis and thus can confer prognostic information additional to that provided by conventional preoperative tumour assessment and staging