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Since the industrial revolution, the civil engineers who created a built environment for a civilisation that is based on fossil fuel have been admired. For over 250 years, engineers have been educated and trained for the 'upslope' of using ever more resources to fuel engineering needs. However, there is now an urgent requirement to enter an era that is an order of magnitude shorter, and which is on the steep 'downslope' towards net-zero carbon dioxide by 2050 or earlier. The difference between what it meant to be an engineer on the upslope and what it means to be engineer on the downslope is colossal. The first step for all educators is to realise this, to embrace it and to be part of the solution by instilling a downslope mentality in engineering students. The Joint Board of Moderators (JBM) has recently reviewed and updated its guidelines for universities. It has placed the climate emergency central to the education of future civil engineers. This paper describes the background to, and details of, the changes made by the JBM. Given that creativity is enhanced through these additional challenges, what could possibly be more exciting for today's engineering students than knowing that they will lead the profession in achieving massive reductions in emissions, to the benefit of all humanity? The JBM, and society, require of civil engineering education that this ambition is fulfilled. [ABSTRACT FROM AUTHOR]

Study Design. Controlled animal study. Objective. To assess the cellular contribution of autograft to spinal fusion and determine the effects of intraoperative storage conditions on fusion. Summary of Background Data. Autograft is considered the gold standard graft material in spinal fusion, purportedly due to its osteogenic properties. Autograft consists of adherent and nonadherent cellular components within a cancellous bone scaffold. However, neither the contribution of each component to bone healing is well understood nor are the effects of intraoperative storage of autograft. Materials and Methods. Posterolateral spinal fusion was performed in 48 rabbits. Autograft groups evaluated included: (1) Viable, (2) partially devitalized, (3) devitalized, (4) dried, and (5) hydrated iliac crest. Partially devitalized and devitalized grafts were rinsed with saline, removing nonadherent cells. Devitalized graft was, in addition, freeze/thawed, lysing adherent cells. For 90 minutes before implantation, air dried iliac crest was left on the back table whereas the hydrated iliac crest was immersed in saline. At 8 weeks, fusion was assessed through manual palpation, radiography, and microcomputed tomography. In addition, the cellular viability of cancellous bone was assayed over 4 hours. Results. Spinal fusion rates by manual palpation were not statistically different between viable (58%) and partially devitalized (86%) autografts (P = 0.19). Both rates were significantly higher than devitalized and dried autograft (both 0%, P < 0.001). In vitro bone cell viability was reduced by 37% after 1 hour and by 63% after 4 hours when the bone was left dry (P < 0.001). Bone cell viability and fusion performance (88%, P < 0.001 vs. dried autograft) were maintained when the graft was stored in saline. Conclusions. The cellular component of autograft is important for spinal fusion. Adherent graft cells seem to be the more important cellular component in the rabbit model. Autograft left dry on the back table showed a rapid decline in cell viability and fusion but was maintained with storage in saline. [ABSTRACT FROM AUTHOR]

A domestic supply chain to produce 238Pu fuel for radioisotope thermoelectric generators is critical for enabling future space exploration. A multi-laboratory effort has worked to establish a common target design to efficiently produce 238Pu in two research reactors. This approach ensures that the annual production goals set forth by NASA are met, while also establishing redundant production capabilities. This paper describes the effort to develop the common target design as well as considerations for future applications for the irradiation platform. • The work details the redesign of a new Pu-238 production target. • The experiment was redesigned to accommodate a single target design capable of irradiation in HFIR and the ATR. • The manuscript describes the modification required of both reactor facilities. • The target is referred to as the HFIR Generation III or ATR Generation I designs. [ABSTRACT FROM AUTHOR]

The optimal sterilization method for load bearing allografts remains a clinical concern. Recently, supercritical carbon dioxide (SCCO2) treatments have been shown to be capable of terminally sterilizing a range of bacteria and viruses, while preserving the static mechanical properties of cortical bone. This study evaluated the effect of SCCO2 treatment compared with two doses of gamma irradiation, on clinically relevant dynamic mechanical properties of cortical bone. Quasi-static testing was also performed to compare the impairment of treatment. Whole paired adult rabbit humeri were dissected and randomly assigned into either SCCO2 Control, SCCO2 Additive or gamma irradiation at 10 or 25 kGy treatment groups. The bones were treated and mechanically tested in three-point bending, with the lefts acting as controls for the treated rights. Maximum load, energy to failure and stiffness were evaluated from static tests. The number of cycles to failure was determined for fatigue at 6-60% of the ultimate load. This study found that SCCO2 treatment with or without additive did not alter static or dynamic mechanical properties. Gamma irradiation had a deleterious dose dependent effect, with statistically significant (p < 0.05) reductions in all static mechanical parameters at 25 kGy. This effect was increased in fatigue with statistically significant decreases in both the 10 and 25 kGy dose groups. This study highlights the expediency of SCCO2 treatment for load bearing bone allograft processing as terminal sterilization can be achieved while maintaining both the quasi-static and dynamic mechanical properties of the graft. [ABSTRACT FROM AUTHOR]

Today's workflow management systems (WfMSs) offer workitems to users through specific worklists. Users select the workitems they will perform without having a schedule in mind. However, in many environments work needs to be scheduled and performed at particular times. For example, in hospitals many workitems are linked to appointments, e.g., a doctor cannot perform surgery without reserving an operating theater and making sure that the patient is present and ready. One of the problems when applying workflow technology in such domains is the lack of calendar-based scheduling support. In collaboration with the Academic Medical Center (AMC), a large hospital in the Netherlands, we developed a schedule-aware WfMS that supports the seamless integration of unscheduled (flow) and scheduled (schedule) tasks. However, before deployment of the resultant system in the hospital, a seamless integration with AMC's running healthcare processes needs to be guaranteed. Therefore, for a large and complex healthcare process, we apply computer simulation to validate and to investigate, for different configurations of the system, the operational performance for a selected healthcare process when supported by the schedule-aware workflow management system. One of the important characteristics of our approach is the tight coupling between the simulation model and the actual implemented system. While performing simulation experiments, parts of the system may be simulated using CPN Tools while connected to the actual system components. Our simulation experiments demonstrate that the developed schedule-aware WfMS can be safely applied in the AMC hospital. [ABSTRACT FROM AUTHOR]

Real-time PCR is an extremely powerful technique, however, often its results are open to interpretation since there is no convention for data presentation. This anomaly has arisen because many applications rely on non-standard calibration genes, which themselves often change in value during experimental manipulation.We present a novel method for absolute quantification of cDNA species using a combination of extremely accurate double-stranded DNA quantification and a plasmid reference curve. PicoGreen and reference standards are used to measure the amount of cDNA present in a sample using fluorescence. Real-time PCR products are cloned into plasmids and then used to calibrate unknown samples. This cloning is achieved using the same primers necessary for real-time PCR and thus does not involve a second design stage. Results are expressed as copy number per microgram of oligo-dT primed cDNA and consequently may be compared between both inter and intra-experimentally. We show results from a sample human system in which absolute levels of interferon-γ, TNF-α, interleukin-2 and interleukin-10 are measured. We further compare the copy numbers of these genes with levels of released protein and find remarkable correlation. Although our interest has been cytokine quantification, we believe that this technique is widely applicable to the majority of real-time PCR applications. [Copyright &y& Elsevier]

Comments on the organizational origin of failures in the information technology (IT) departments of businesses. Evidence from a large scale international survey of IT professionals; Description of a number of specific organizational problems that contribute to the lack of understanding and impede the creation of a flexible and responsive IT department.

We are reporting a case of nonabsorbable suture-induced osteomyelitis in patient who had an open rotator cuff repair with nonabsorbable Ethibond anchor suture. Patient in this case presented with very subtle clinical features of osteomyelitis of the left proximal humerus 15 years after initial rotator cuff repair surgery. Literature had shown that deep infection following rotator cuff repairs, although rare, can be easily missed and can cause severe complications. Absorbable suture had been demonstrated to be more superior, in terms of rate of deep infection, as compared to nonabsorbable suture when used in rotator cuff repair surgery. Both absorbable and nonabsorbable suture had been demonstrated to have similar mechanical properties by several different studies. The case demonstrated that initial presentation of deep infection can be subtle and easily missed by clinicians and leads to further complications. [ABSTRACT FROM AUTHOR]

Background: Patients with anorexia nervosa (AN) may experience life‐threatening malnutrition‐related complications requiring inpatient medical stabilisation. Several management guidelines have been developed but discrepancies exist because of limited high‐level evidence. Aims: To review the evidence base for recommendations contained in Victorian health services guidelines for the nutritional management of inpatients with AN. Methods: MEDLINE and Embase databases were searched for published studies on the nutritional management of inpatients with AN, combined with a manual search through citations. Studies including patients with AN aged 16 years and older were included. Case reports, small case series of <10 patients, studies of nonmedical management and studies with an exclusive paediatric population were excluded. The search results were compared with AN inpatient medical management guidelines sourced from large tertiary health services across Victoria, Australia. Results: The search yielded 584 studies, subsequently reduced to nine studies using the inclusion and exclusion criteria. The results suggest that commencing refeeding at a higher caloric value allows faster weight gain and shorter hospitalisation. Enteral tube feeding is preferential to parenteral nutrition because of infrequent and milder complications. Zinc supplementation showed a doubled rate of body mass index increase compared with placebo. Comparison with Victorian health services guidelines revealed inconsistent recommendations for high‐calorie refeeding and micronutrient supplementation. Conclusion: The evidence supports high‐calorie refeeding of 2000 kcal/day in AN inpatient medical management and zinc supplementation in improving the rate of weight restoration. This is inconsistently reflected in different Victorian health services guidelines. Updated national consensus guidelines could assist in improving consistency of evidence‐based health care. [ABSTRACT FROM AUTHOR]

• Thermal conductivity of molten eutectic LiF-NaF-KF is measured from 834 to 1195 K with the variable gap technique. • Thermal conductivity of LiF-NaF-KF is predicted with a kinetic theory derived model and equilibrium molecular dynamics. • Temperature dependence of the thermal conductivity of LiF-NaF-KF is discussed from an experimental and theoretical viewpoint. • Inconsistencies between experimental data on thermal conductivity of molten LiF-NaF-KF reported in literature are discussed. • Mapping of the thermal conductivity of LiF-NaF-KF is proposed in the entire range of temperature from 750 K to 1300 K. Molten salts are being proposed for numerous advanced energy applications, including advanced nuclear reactors, concentrating solar power plants, thermal energy storage, and fusion reactors. Accurate knowledge of the thermophysical properties of molten salts directly impact the performance of these energy systems and are essential for design and safety analyses. Thermal conductivity data for fluoride molten salts and mixtures are especially lacking. In this work, experimental measurements of thermal conductivity using the steady-state variable gap technique were performed on eutectic LiF-NaF-KF from 834 to 1195 K. The experiment accounts for radiative, convective, and conductive heat losses. In addition, theoretical and molecular dynamics models are used, from 750 K up to 1300 K, to estimate the thermal conductivity for comparison with the experimental results. The results of experiments show a weak negative deviation of thermal conductivity with temperature, unlike previous experimental results in the literature. The measured thermal conductivity magnitudes agree with the theoretical and molecular dynamics predictions, aside from the data above 1100 K, where heat losses and radiative errors are the most significant, having a 16% maximum deviation from theory. These experimental results provide new thermal conductivity data for the LiF-NaF-KF system and further validation of the predictive models. The theoretical model was used to map the composition and temperature dependent thermal conductivity of LiF-NaF-KF and the mapping's deviation from a linear additivity estimation of thermal conductivity. This mapping showed the highest deviations from linearity for KF-LiF rich mixtures and increasing deviation with temperature. Notably, the deviation from linearity near the LiF-NaF-KF eutectic composition was around 25%. [ABSTRACT FROM AUTHOR]

Autograft has historically been considered the gold standard graft material for spinal fusion, purportedly due to its osteogenic properties. Autograft consists of both adherent and nonadherent cellular components within or surrounding a cancellous bone scaffold. Thus, the bone forming potential of autograft may derive from adherent cells and/or the nonadherent cellular milieu (ie, bone marrow cells). However, the contribution of each component in spinal fusion is not well understood. During surgery, autograft may be left out on the back table for prolonged periods of time, which may adversely affect osteogenic potential. Furthermore, there has recently been controversy over the role of cells in allogeneic cell bone matrices, which begs additional questions about the role of cells in autograft. This study tested viable autograft, partially devitalized autograft (nonadherent cells removed), and devitalized autograft (nonadherent cells removed and adherent cells lysed) in a rabbit spinal fusion model. Additionally, autograft left out on the back table or immersed in saline for 90 minutes were also tested to simulate intraoperative handling of autograft. The hypotheses of this study are that both viable and partially devitalized autograft outperform devitalized autograft in a rabbit spinal fusion model, and that fusion performance is adversely affected by bone being left out dry under ambient conditions. Controlled basic science study. Posterolateral spinal fusion was performed using the standard Boden model in 40 New Zealand white rabbits. Eight rabbits were assigned each to viable iliac crest, partially devitalized iliac crest, devitalized iliac crest, dried iliac crest and hydrated iliac crest (2.5cc per side). Partially devitalized and devitalized grafts were vigorously rinsed with saline to remove nonadherent cells. Devitalized graft was additionally freeze/thawed to lyse adherent cells. Dried iliac crest was left on the back table for 90 minutes prior to implantation. Hydrated iliac crest was immersed in saline for 90 minutes prior to implantation. Fusion was assessed at 8 weeks via manual palpation and microCT. Spinal fusion by manual palpation was 7/12 (58%), 12/14 (86%), and 14/16 (88%) for viable, partially devitalized and hydrated autograft, respectively, which were not statistically different. All three fusion rates were significantly higher (p<.001) than both the devitalized and dried autograft groups (both 0/16, 0%). Three animals (6 fusion masses) died after surgery (2 from the viable group and 1 from the partially devitalized group) and were not replaced. Viable iliac crest resulted in significantly higher spinal fusion rates compared to devitalized autograft. Thus, the cellular component of autograft is important for spinal fusion. Similar fusion results for viable and partially devitalized autograft suggest that adherent graft cells, not the non-adherent cellular milieu, are the more important cellular component for fusion in the rabbit model. When autograft is left out dry on the back table, fusion performance drops significantly. However, graft performance can be maintained similar to viable iliac crest by immersing the graft in saline. These results suggest that intraoperative handling of autograft may substantially affect graft performance in spinal fusion. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]

• Techniques used for the measurement of thermal conductivity are reviewed. • A steady state instrument designed to measure the thermal conductivity is presented along with the measurement theory. • Tested on helium and KNO 3 NaNO 3 molten salt from 300 °C to 500 °C. • Effects of convection and radiation were mitigated using this technique. • Conductive heat losses will need to be minimized to extend operability above 500 °C. High-temperature fluids such as molten salts, liquid metals, and gasses are being proposed for many advanced energy systems including thermal energy storage devices, concentrating solar plants, and advanced nuclear reactor designs. However, the chemical behavior and thermophysical properties of many of these fluids have not been well characterized, which hinders the design, modeling, safety analysis, and deployment of these systems. Thermal conductivity is a property that is especially limited by existing measurement capabilities, which are subject to errors caused by convection, material interaction, radiative heat transfer, and instrument degradation. Therefore, there is a lack of standard, systematic measurement techniques for high-temperature, reactive, and corrosive fluids. In this work, the development of a variable gap thermal conductivity measurement system is detailed. The system is designed to measure the thermal conductivity of highly corrosive and reactive fluids, and survive operation between 100 °C and 800 °C. The effects of convection are minimized by limiting the thickness of the specimen to thin sizes (<0.3 mm). Corrections for radiative heat transfer were included in the working equations to consider specimens with varying optical properties. The design, construction, instrumentation, operating principles, and data analysis techniques are discussed in detail. The system was tested up to 500 °C using helium gas and molten KNO 3 NaNO 3 to verify the measurement technique and determine the sources of error. At 300 and 400 °C KNO 3 NaNO 3 , results showed maximum relative error of 6% when compared to results in the literature. The helium results were within 13% of those in the literature at 300 and 400 °C. Higher errors were observed at 500 °C for both fluids, and the sources of these errors are discussed. [ABSTRACT FROM AUTHOR]

There is clear evidence that certain forms of immunotherapy can be successful against certain cancers. However, it would appear that cancerous cells of various origin are exceptionally adept at subverting the immune response. Consequently, it is probable that the most efficacious therapy will be one in which multiple responses of the immune system are activated. There is currently an embarrassment of riches with regard to multiple vaccine strategies in the clinic, although no single method seems to hold the solution. Here, we draw together several of the humoral- and cellular-activating strategies currently under clinical investigation. [Copyright &y& Elsevier]

Antarctic microbial biodiversity is the result of a balance between evolution, extinction and colonization, and so it is not possible to gain a full understanding of the microbial biodiversity of a location, its biogeography, stability or evolutionary relationships without some understanding of the input of new biodiversity from the aerial environment. In addition, it is important to know whether the microorganisms already present are transient or resident – this is particularly true for the Antarctic environment, as selective pressures for survival in the air are similar to those that make microorganisms suitable for Antarctic colonization. The source of potential airborne colonists is widespread, as they may originate from plant surfaces, animals, water surfaces or soils and even from bacteria replicating within the clouds. On a global scale, transport of air masses from the well-mixed boundary layer to high-altitude sites has frequently been observed, particularly in the warm season, and these air masses contain microorganisms. Indeed, it has become evident that much of the microbial life within remote environments is transported by air currents. In this review, we examine the behaviour of microorganisms in the Antarctic aerial environment and the extent to which these microorganisms might influence Antarctic microbial biodiversity. [ABSTRACT FROM AUTHOR]

Allogeneic whole tumour cell vaccines are inherently practical compared with autologous vaccines. Cell lines are derived from allogeneic tumour, grown in bulk and then administered as a vaccine to the patient, following irradiation, which not only prevents any replication but also enhances antigen presentation. Protection is believed to occur through the presentation of antigens shared between the syngeneic and allogeneic tumours. Although cytokine-transfected tumour whole cell vaccines have been used clinically, little data is available comparing the effects of immunomodulatory cytokine-transfection directly on the same cells when used as both an allogeneic and autologous vaccine. To address this, weakly immunogenic B16-F10 (H-2b) murine melanoma was transfected to secrete either GM-CSF, IL-4 or IL-7. Prophylactic vaccination of both syngeneic C57/BL6 (H-2b) (B6) and allogeneic C3H/Hej (H-2k) (C3H) mice showed the effects of transfected cytokine varied between models. Both GM-CSF and IL-7 significantly ( P<0.05) increased the levels of protection within syngeneic B6 mice, but had a diminished effect ( P>0.05) within C3H allogeneic mice. Allogeneic B16-F10 cells and syngeneic K1735 cells generated CTL against K1735 suggesting cross-reactive immunity. Using cells labeled with fluorescent dye we demonstrate that irradiated vaccines, of either syngeneic or allogeneic origin, appear to generate potent immune responses and fragments of either vaccine remain at the injection site for up to 9 days. This study shows that protection can be enhanced in vivo by using transfected cytokine, but suggests that irradiated whole cell vaccines, of either tissue-type, are rapidly processed. This leads to the conclusion that the cytokine effects are transient and thus transfection with cytokine may be of limited long-term use in situ. [ABSTRACT FROM AUTHOR]