Engineering the future with America's high school students

The number of students enrolled in engineering is declining while the need for engineers is increasing. One contributing factor is that most high school students have little or no knowledge about what engineering is, or what engineers do. To teach young students about engineering, engineers need good tools. This paper presents a course of study developed and used by the authors in a junior college course for high school students. Students learned about engineering through independent student projects, in-class problem solving, and use of career information resources. Selected activities from the course can be adapted to teach students about engineering in other settings. Among the most successful techniques were the student research paper assignments, working out a solution to an engineering problem as a class exercise, and the use of technical materials to illustrate engineering concepts and demonstrate 'tools of the trade'

EVALUATION OF METHANE GAS PRODUCTION IN A SIMULTANEOUS REGRESSION SYSTEM

Methane gas production is a function of volatile solids activity in anaerobic digesters. Increasing the solids retention time of the swine manure digester system without increasing the hydraulic retention time would theoretically increase the methane gas production efficiency. Coagulation treatments were performed on the effluent of the second digester in a system of two digesters in series . The objective of this paper is to describe mathematically the relationship of the Coagulation treatments in the second digester to biogas production and volatile solids retention. An initial, single equation, ordinary least squares regression produced statistically significant parameter estimates, but failed to accurately describe the treatment activity occurring in the second digester. To assess the treatment activity of the second digester and account for the activity of first digester on the second, data was regressed through a simultaneous equation system. Both two-stage and three-stage least squares regression were examined

Cumulate causes for the low contents of sulfide-loving elements in the continental crust

Despite the economic importance of chalcophile (sulfide-loving) and siderophile (metal-loving) elements (CSEs), it is unclear how they become enriched or depleted in the continental crust, compared with the oceanic crust. This is due in part to our limited understanding of the partitioning behaviour of the CSEs. Here I compile compositional data for mid-ocean ridge basalts and subduction-related volcanic rocks. I show that the mantle-derived melts that contribute to oceanic and continental crust formation rarely avoid sulfide saturation during cooling in the crust and, on average, subduction-zone magmas fractionate sulfide at the base of the continental crust prior to ascent. Differentiation of mantle-derived melts enriches lower crustal sulfide- and silicate-bearing cumulates in some CSEs compared with the upper crust. This storage predisposes the cumulate-hosted compatible CSEs (such as Cu and Au) to be recycled back into the mantle during subduction and delamination, resulting in their low contents in the bulk continental crust and potentially contributing to the scarcity of ore deposits in the upper continental crust. By contrast, differentiation causes the upper oceanic and continental crust to become enriched in incompatible CSEs (such as W) compared with the lower oceanic and continental crust. Consequently, incompatible CSEs are predisposed to become enriched in subduction-zone magmas that contribute to continental crust formation and are less susceptible to removal from the continental crust via delamination compared with the compatible CSEs

A Stratabound Zinc-Lead Deposit in Meguma Group Metasediments at Eastville, Nova Scotia

The Eastville zinc-lead deposit, discovered by soil sampling in 1976, occurs near the contact of the Goldenvllle and Halifax Formations, the two divisions of the Cambro-Ordovician Meguma Group. The stratigraphic succession in the contact zone comprises an assemblage of quartz metawacke, calcareous quartz metawacke and slate. Quartz metawacke is predominant in the Goldenvllle Formation and slate is the dominant lithology in the overlying Halifax Formation. These rocks are interpreted as the middle to outer fan and basin plain deposits of a submarine fan complex. Pyrrhotite and pyrite, the predominant Bulphide minerals in all lithologles in the contact zone, were deposited by reduction of iron in the sediments, independent of the mineralizing process. Sphalerite and galena occur in rocks over a 10 km strike length in elongate blebs, 2 to 5 mm long, distributed parallel to bedding and in cross-cutting fractures. The deposit is stratabound and generally occurs in black slate beds near the Goldenvllle-Halifax contact. Geochemical analyses of the rocks have indicated a concentration of Mn in the calcareous quartzite member, the upper unit of the Goldenville Formation. A relationship between the Mn enrichment and the abundance of sphalerite and galena in the section has not been established. The sulphide mineralogy, laterally continuous stratigraphy and lack of metal zonation and underlying feeder structures indicate the sphalerite and galena were syngenetically deposited from metal-rich brines at a site distant from where the brines entered the basin of deposition- RÉSUMÉ Le dépôt de plomb at de zinc de Eastville, qui a été découvert par des prises d'échantillons de terre en 1976, est situé pré du contact des formations Goldenville et Halifax (les deux unités du groupe Meguma). La succession stratigraphique dans la zone de contact est constitué d'un assemblage de métagrauwacke de quartz, de métagrauvacke calcaire de quartz, et d'ardoise. Le métagrauwacke de quartz est prédominant dans la formation Goldenville et l'ardoise est la lithologie dominate de la formation de Halifax, qui est superposé sur la première. Ces roches sont expllquées comme étant le cône central ou extérieur et des dépôts de la plaine d'un basin d'un compiexe de cône. La pyrrhotite et la pyrite, les minéraux sulfides principalis dans toutes les lithologles de la zone de contact, ont été déposés par une réduction de fer dans les sédiments, indépendement des processus de minéralisation. La sphalérite et la galène se trouvent dans les roches sur une longueur de 10 kilomètres le long de la couche en temps que soufflures de 2 à 5 mm de longueur, réparties paralèllement à la couche et dans les fractures à trafers banc. Le dépôt est limite aux strates et se crouve en général dans de l'ardoise noire près du contact Goldenville-Halifax. Des analyses géochimiques des roches ont indiqué une concentration de Mn dans les quartzites calcaires, l'unité la plus é1evé de la formation Goldenville. Un rapport entre l'enrichiasement en Mn et l'abondance de la sphalerite et de la galène dans la section, n'a pas été établie. La minéralogie des sulfides, la stratigraphie laterale continue, et le manque de zonation de métaux et de structures de conduite d'alimentation, indique que la sphalerite et la galène ont été déposées sygénétiquement à partir de saumures riches en métaux dans un site éloigné de l'endroit où les saumures pénétrent le basin de dépôt. [Traduit par le journal

CD90 is not constitutively expressed in functional innate lymphoid cells

Huge progress has been made in understanding the biology of innate lymphoid cells (ILC) by adopting several well-known concepts in T cell biology. As such, flow cytometry gating strategies and markers, such as CD90, have been applied to indentify ILC. Here, we report that most non-NK intestinal ILC have a high expression of CD90 as expected, but surprisingly a sub-population of cells exhibit low or even no expression of this marker. CD90-negative and CD90-low CD127+ ILC were present amongst all ILC subsets in the gut. The frequency of CD90-negative and CD90-low CD127+ ILC was dependent on stimulatory cues in vitro and enhanced by dysbiosis in vivo. CD90-negative and CD90-low CD127+ ILC were a potential source of IL-13, IFNγ and IL-17A at steady state and upon dysbiosis- and dextran sulphate sodium-elicited colitis. Hence, this study reveals that, contrary to expectations, CD90 is not constitutively expressed by functional ILC in the gut

Early relapse after high‐dose melphalan autologous stem cell transplant predicts inferior survival and is associated with high disease burden and genetically high‐risk disease in multiple myeloma

Predicting patient outcome in multiple myeloma remains challenging despite the availability of standard prognostic biomarkers. We investigated outcome for patients relapsing early from intensive therapy on NCRI Myeloma XI. Relapse within 12 months of autologous stem cell transplant was associated with markedly worse median progression‐free survival 2 (PFS2) of 18 months and overall survival (OS) of 26 months, compared to median PFS2 of 85 months and OS of 91 months for later relapsing patients despite equal access to and use of subsequent therapies, highlighting the urgent need for improved outcome prediction and early intervention strategies for myeloma patients

The relative importance of factors predicting outcome for myeloma patients at different ages: results from 3894 patients in the Myeloma XI trial.

Disease factors such as tumor burden and molecular risk affect myeloma patient outcomes as well as patient factors that impact the capacity to deliver treatment. How the relative importance of these factors changes with patient age has not previously been investigated comprehensively. We analyzed data from 3894 patients of all ages uniformly treated in a large clinical trial of myeloma patients, Myeloma XI. Even with novel therapeutic approaches progression-free survival (PFS) and overall survival (OS) are affected by age with a stepwise reduction in PFS and OS with each decade increase. Renal function deteriorated with increasing age whilst the frequency of t(4;14) and del(17p) decreased and gain(1q) increased. The relative contribution of performance status, international staging score and molecular risk to progression-free and overall survival varied by age group. Molecular events have a larger effect on outcome in younger patients with their relative contribution diminishing in the elderly. Performance status is important for patient outcome at all ages suggesting that physical frailty may be a more important predictor of outcome than age itself. Significant differences in the factors driving patient outcomes at different ages are important to consider as we design disease segmentation strategies to deliver personalized treatment approaches

Cyclin-dependent kinase 9 as a potential target for anti-TNF resistant inflammatory bowel disease

BACKGROUND AND AIMS: Resistance to single cytokine blockade, namely anti-TNF therapy, is a growing concern for patients with inflammatory bowel disease (IBD). The transcription factor T-bet is a critical regulator of intestinal homeostasis, is genetically linked to mucosal inflammation and controls the expression of multiples genes such as the pro-inflammatory cytokines IFN-γ and TNF. Inhibiting T-bet may therefore offer a more attractive prospect for treating IBD but remains challenging to target therapeutically. In this study, we evaluate the effect of targeting the transactivation function of T-bet using inhibitors of P-TEFb (CDK9-cyclin T), a transcriptional elongation factor downstream of T-bet. METHODS: Using an adaptive immune-mediated colitis model, human colonic lymphocytes from IBD patients and multiple large clinical datasets, we investigate the effect of CDK9 inhibitors on cytokine production and gene expression in colonic CD4+ T cells and link these genetic modules to clinical response in patients with IBD. RESULTS: Systemic CDK9 inhibition led to histological improvement of immune-mediated colitis and was associated with targeted suppression of colonic CD4+ T cell-derived IFN-γ and IL-17A. In colonic lymphocytes from IBD patients, CDK9 inhibition potently repressed genes responsible for pro-inflammatory signalling, and in particular genes regulated by T-bet. Remarkably, CDK9 inhibition targeted genes that were highly expressed in anti-TNF resistant IBD and that predicted non-response to anti-TNF therapy. CONCLUSION: Collectively, our findings reveal CDK9 as a potential target for anti-TNF resistant IBD, which has the potential for rapid translation to the clinic

The IUCF Cooler Project

This research was sponsored by the National Science Foundation Grant NSF PHY 87-1440

Implementation of Whole-Body MRI (MY-RADS) within the OPTIMUM/MUKnine multi-centre clinical trial for patients with myeloma.

BACKGROUND: Whole-body (WB) MRI, which includes diffusion-weighted imaging (DWI) and T1-w Dixon, permits sensitive detection of marrow disease in addition to qualitative and quantitative measurements of disease and response to treatment of bone marrow. We report on the first study to embed standardised WB-MRI within a prospective, multi-centre myeloma clinical trial (IMAGIMM trial, sub-study of OPTIMUM/MUKnine) to explore the use of WB-MRI to detect minimal residual disease after treatment. METHODS: The standardised MY-RADS WB-MRI protocol was set up on a local 1.5 T scanner. An imaging manual describing the MR protocol, quality assurance/control procedures and data transfer was produced and provided to sites. For non-identical scanners (different vendor or magnet strength), site visits from our physics team were organised to support protocol optimisation. The site qualification process included review of phantom and volunteer data acquired at each site and a teleconference to brief the multidisciplinary team. Image quality of initial patients at each site was assessed. RESULTS: WB-MRI was successfully set up at 12 UK sites involving 3 vendor systems and two field strengths. Four main protocols (1.5 T Siemens, 3 T Siemens, 1.5 T Philips and 3 T GE scanners) were generated. Scanner limitations (hardware and software) and scanning time constraint required protocol modifications for 4 sites. Nevertheless, shared methodology and imaging protocols enabled other centres to obtain images suitable for qualitative and quantitative analysis. CONCLUSIONS: Standardised WB-MRI protocols can be implemented and supported in prospective multi-centre clinical trials. Trial registration NCT03188172 clinicaltrials.gov; registration date 15th June 2017 https://clinicaltrials.gov/ct2/show/study/NCT03188172