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Improving hard machining efficiency is a growing concern in industrial production, but environmentally friendly characteristics are guaranteed. Nanofluid minimum quantity lubrication (NF MQL) has emerged as a promising solution to improve cooling and lubrication performance in the cutting zone. This paper utilizes Box-Behnken experimental design to identify the influences of Al2O3/MoS2 hybrid nanofluid MQL hard turning using CBN inserts on surface roughness and cutting forces. Mathematical models were employed to predict thrust cutting force, tangential cutting force, and surface roughness in hard turning under MQL conditions using Al2O3/MoS2 hybrid nanofluid. The study results reveal that the minimum thrust force (Fy) occurs at a nanoparticle concentration of 0.5%, air pressure of 5 bar, and flow rate of 236 l/min. In comparison, the tangential force (Fz) reaches its minimum at a nanoparticle concentration of 0.8%, air pressure of 5 bar, and airflow rate of 227 l/min. The minimum surface roughness was achieved with a nanoparticle concentration of 1%, air pressure of 4.7 bars, and airflow rate of 186 l/min. Additionally, based on the multi-objective optimization, an optimal parameter set of NC=1%, p=5 bar, and Q = 210 l/min was identified to bring out the minimal values of surface roughness (Ra) of 0.218 µm, thrust force (Fy) of 115.9 N, and tangential force (Fz) of 93.3 N.

To improve the recycling of solid waste and achieve the secondary utilization of waste resources, this study investigates the preparation of molybdenum tailings composited binders by high temperature calcination using molybdenum tailings, limestone, bauxite, and iron concentrate powder. Besides, to explore the mechanical properties of the new molybdenum tailings composited binders, a molybdenum tailings composited mortar was prepared. The mechanical properties, micro performance and hydration mechanism of the new molybdenum tailings composited binders were studied. Finally, the carbon dioxide emission of green molybdenum tailings composited binders/molybdenum tailings composited mortar was evaluated by the life cycle assessment method. The results show that the compressive strength of molybdenum tailings composited binders gradually increases with the increase of calcination temperature. When the calcination temperature is 1350 °C, the compressive strength and flexural strength at 28 days are 44.17 MPa and 7.56 MPa, respectively, which are 3.65 % and 4.63 % higher than control group made by P·O 42.5 cement. The early strength of molybdenum tailings composited binders increases slowly, and the later strength increases rapidly. In addition, there is more C2S in the matrix, resulting in a slow hydration heat rate and low cumulative hydration heat. Compared with other groups, the hydration kinetic parameters and hydration rate of molybdenum tailings composited binders under 1350 °C were the lowest. The main hydration prodcuts of molybdenum tailings composited binders are C-S-H, calcium hydroxide, and Aft gels. Compared with P·O 42.5 cement paste and mortar, the carbon dioxide emission of molybdenum tailings composited binders/molybdenum tailings composited mortar is reduced by 42.82 % and 29.08 %, respectively, which can indicate that the new binders can produce less carbon dioxide. Overall, this study can provide new ways for the development of the new binder mixed with plenty of molybdenum tailings, and offer a novel way for recycling the molybdenum tailings, and also present some valuable experimental results for the application of molybdenum tailings in infrastructures.

A cost-effective approach is urgently needed to utilize molybdenum tailings (MoT), a mining byproduct with rising output. This study explored the preparation of molybdenum tailings collaborative fly ash (FA) geopolymers (MFG) from mechanically activated MoT and FA raw materials. Orthogonal experiments investigated the impacts of various parameters on the compressive strengths of the MFG. The macroscopic properties of MFG with different mixture ratios were evaluated. The microstructures and components of the MFG were characterized using various methods. Fractal dimensions (Ds) of pore structures in the MFG samples were determined. Carbon emissions resulting from the production of MFG geopolymers were calculated and evaluated using Low carbon Assessment. The findings showed that increasing the content of mechanically activated MoT in the MFG system decreased flowabilities and prolonged setting times. The optimal MoT-to-FA ratio for achieving the highest compressive strength of 31.26 MPa was 1:4, resulting in a Si/Al ratio of 2.03 in the MFG system. XRD, TG, SEM-EDS, and FTIR analyses confirmed the primary product of the MFG was a glassy hydrated sodium-aluminum silicate (N-A-S-H) gel. MIP analysis revealed that addition of mechanically activated MoT improved the pore structure of the MFG, leading to smaller pores. Additionally, for MFG composed solely of MoT or FA, the Ds was smaller, and smaller particles of the raw materials also led to smaller Ds values. Conversely, when the raw materials were mixed, larger Ds values were observed, and a closer volume fraction for the two raw materials resulted in larger Ds values. Furthermore, the carbon emission analysis revealed that the carbon emissions of MFG geopolymers were reduced by 45.4 %-64.3 % compared to traditional OPC slurries.

Abstract Rapid and sensitive detection of pathogens is critical in interrupting the transmission chain of infectious diseases. Currently, real-time (RT-)PCR represents the gold standard for the detection of SARS-CoV-2. RNase HII-assisted amplification (RHAM) is a promising technology, enabling reliable point-of-care (PoC) testing; however, its diagnostic accuracy has not yet been investigated. The present study compared the Pluslife Mini Dock (RHAM technology), with Abbott ID Now and Cepheid GeneXpert IV. The positive percent agreement (PPA) and negative percent agreement (NPA) were determined in 100 SARS-CoV-2 positive and 210 SARS-CoV-2 negative samples. Further, the reliability of the Pluslife Mini Dock was investigated in different SARS-CoV-2 variants (Delta and Omicron subvariants). The PPA was 99.00% for Pluslife, 100.00% for Abbott ID Now, and 99.00% for Cepheid GeneXpert, with an NPA of 100.00%, 98.90%, and 93.72%, respectively. Abbott ID Now demonstrated the highest rate of invalid results. All SARS-CoV-2 analysed variants were detected by the Pluslife device. Altogether, the Pluslife Mini Dock demonstrated a PPA of 99.16% (235/237) for CT

Geopolymer concrete emerges as a sustainable and durable alternative to conventional concrete, addressing its high carbon footprint and enhanced durability. The distinct properties of geopolymer concrete, governed by supplementary cementitious materials and alkaline activators, promise reduced environmental impact and improved structural resilience. However, its complex composition complicates the prediction of mechanical properties such as the elastic modulus, crucial for structural applications. This study introduces an innovative approach using the eXtreme Gradient Boosting (XGBoost) technique integrated with the multi-objective grey wolf optimizer to model the elastic modulus of geopolymer concrete. By dynamically selecting influential features and optimizing model accuracy, this methodology advances beyond traditional empirical models, which fail to capture the nonlinear interactions intrinsic to geopolymer concrete. Utilizing a comprehensive database gathered from extensive literature, 22 potential variables were examined that influence geopolymer concrete’s elastic modulus. After mitigating multicollinearity and optimizing hyperparameters via Bayesian optimization, six XGBoost models were developed with different combinations of input variables, revealing compressive strength and total water content as pivotal predictors. The findings illustrate the models’ precision, with the trade-off between prediction accuracy and model simplicity visualized through the relationship between the number of input variables and prediction error. The study culminates in a user-friendly graphical user interface that enables easy prediction of geopolymer concrete’s elastic modulus and fosters educational engagement. This interface, available online, underscores the practicality and accessibility of advanced machine learning predictions. Overall, this research not only provides a robust predictive framework for geopolymer concrete’s elastic modulus using optimized input variables but also enhances the understanding of its underlying determinants, contributing to the advancement of sustainable construction materials.

Thermal energy storage (TES) system has been widely employed in concentrated solar power (CSP) plants to ensure the system efficiency. With excellent thermal characteristics, electrolytic copper powder (ECP), graphene oxide (GO) and lead-smelter slag (LSS) aggregate – a mining waste material, have been utilised in this study, aiming to fabricate metallurgical geopolymer material as a storage medium in the TES system. This paper investigated the effect of ECP contents (0, 5%, 10%, 15%, 20%) on the strength, specific heat, thermal conductivity and thermal stability of GO-engineered geopolymer mixes incorporating LSS aggregate. With 10% ECP inclusion, the flow rate and compressive strength improved significantly. Increasing ECP content improved the thermal conductivity but reduce specific heat of geopolymers. The results revealed that ECP was a promising component to be incorporated into geopolymer to enhance its physio-mechanical characteristics and thermal stability. The combination of ECP, GO and LSS to produce geopolymer materials for TES system can provide an eco-friendly solution to the CSP plants and the industry waste recovery.

Enhancing the quality of cultivated mud crabs is a crucial element for elevating productivity, quality, and economic effectiveness within the mud crab farming sector. This study investigates factors influencing the quality of farmed crabs in the Mekong Delta, Vietnam. The study employs descriptive statistical methods and synthesis approaches to analyse the current situation of crab farming in the Mekong Delta, Vietnam. Additionally, multivariate regression analysis was employed to identify factors affecting the quality of farmed crabs in the Mekong Delta, Vietnam. The survey results from 304 crab farmers in the Mekong Delta, Vietnam indicate that the total area of the Mekong Delta, Vietnam is 465 thousand hectares, with a production of 68 thousand tons. Among the provinces in the Mekong Delta, Vietnam, Kien Giang, Ca Mau, and Bac Lieu are the top three provinces with the highest area and production. Furthermore, factors influencing the quality of crab products during the farming process were analysed, and three main factors were identified: the decision to catch crabs at the fourth moult stage (Y4), the number of crab traps used, and the duration of the farming period. This research represents the first study on the quality of farmed crab in the Mekong Delta, Vietnam. Therefore, these findings provide guidelines for improving the quality of farmed crab and serve as a foundation for further research in this field

By-products (wastes or residues) of renewable materials have the potential to be manufactured into higher value fibre insulation products for the Australian market. Currently, such products have been imported for servicing the Australian market. This presents a potential opportunity to divert considerable quantities of waste from landfill and produce a high performance, locally made, low carbon, natural fibre insulation product for the Australian domestic and commercial building industry. This article assesses the hemp-based bulk insulations available in the Australian market.

Multiples zeta values and alternating multiple zeta values in positive characteristic were introduced by Thakur and Harada as analogues of classical multiple zeta values of Euler and Euler sums. In this paper, we determine all linear relations between alternating multiple zeta values and settle the main goals of these theories. As a consequence, we completely establish Zagier–Hoffman’s conjectures in positive characteristic formulated by Todd and Thakur which predict the dimension and an explicit basis of the span of multiple zeta values of Thakur of fixed weight.

In 2007 Chang and Yu determined all the algebraic relations among Goss’s zeta values for $A=\mathbb F_q[\theta ]$ , also known as the Carlitz zeta values. Goss raised the problem of determining all algebraic relations among Goss’s zeta values at positive integers for a general base ring A, but very little is known. In this paper, we develop a general method, and we determine all algebraic relations among Goss’s zeta values for the base ring A which is the coordinate ring of an elliptic curve defined over $\mathbb F_q$ . To our knowledge, this is the first work tackling Goss’s problem when the base ring has class number strictly greater than 1.

Introduction. Pseudoaneurysms of superior mesenteric artery and its branches are extremely rare but life threatening when complications occur. However, the diagnosis is often missed or delayed because of its non-specific signs and symptoms. Treatments depend on patient’s characteristics. In contrast to conventional open surgery, endovascular therapy has been reported as an effective option with minimally invasion, low complication, short recovery time and good outcome, especially in high-risk patients. Case presentation. We describe a case of ruptured pseudoaneurysm of ileal artery, a branch of superior mesenteric artery, presenting with gastrointestinal bleeding signs while on anticoagulant therapy. Both upper and lower gastrointestinal endoscopy were inconclusive. The diagnosis was confirmed by angiography and the patient was successfully treated by coil embolization. Conclusions. Ruptured pseudoaneurysm of superior mesenteric artery and its branches should be suspected in patients with unexplained gastrointestinal hemorrhage. Endovascular intervention is a feasible approach, especially in patients with multiple comorbidities and high bleeding risk.

This paper provides a numerical investigation on the ballistic performance of ceramic composite armour panels with porous architectures inspired by nacre from mollusc shells. The development of such armour panels can lead to reduced weight and improve ballistic performance through projectile rotation induced by non-uniform contact stresses. The porous tablets of nacre have the potential to reduce the mass of armour panels without compromising their ballistic performance. Preliminary simulations were conducted to assess the performance of several porous bio-inspired structures that have the potential to survive projectile impact with less mass. Several bio-inspired panels composed of various porous designs were generated based on the different void architectures of nacre's tablets. Their performances were benchmarked against a monolithic panel under the same projectile impact condition and having the same 4.5 mm overall panel thickness but higher mass. It was found that for the cases considered, the biomimetic panels with porous architectures possess better ballistic performance compared to the corresponding monolithic panel by arresting the projectile having an initial impact velocity of 500 m/s, whilst reducing its mass by up to 18%. A further study was conducted on bio-inspired panels with a higher thickness but the same mass as the solid monolithic panel under the same projectile impact condition. It was found that the bio-inspired panel exhibits significantly improved ballistic performance when subjected to a fragment simulating projectile having an initial velocity chosen to be the ballistic limit velocity of the corresponding monolithic panel.

Biological structures possess excellent damage tolerance, which makes them attractive for ballistic protection applications. This paper develops a finite element modelling framework to investigate the performance of several biological structures that are most relevant for ballistic protection, including nacre, conch, fish scales, and crustacean exoskeleton. Finite element simulations were conducted to determine the geometric parameters of the bio-inspired structures that can survive projectile impact. The performances of the bio-inspired panels were benchmarked against a monolithic panel with the same 4.5 mm overall thickness and projectile impact condition. It was found that the biomimetic panels that were considered possessed better multi-hit resistant capabilities compared to the selected monolithic panel. Certain configurations arrested a fragment simulating projectile with an initial impact velocity of 500 m/s, which was similar to the performance of the monolithic panel.

Waste glass stockpiling is a significant issue in Australia with approximately 66 kilo tonnes of uneconomic and contaminated waste glass fines being produced each year in Victoria alone. The high level of contaminants in waste glass fines could be harmful to concrete while washing glass is not economical and sustainable. Limited research has investigated the effect of contaminants in waste glass fines on the performance of concrete, which has hampered its broader acceptance as a substitution for natural sand aggregate. In this study, the feasibility of utilising unwashed waste glass fines as a sand replacement at 10 wt% was comprehensively investigated, under both laboratory and on-site conditions. Minor differences were observed in both mechanical and durability properties between concrete with and without waste glass fines at 10 wt% replacement. Overall, this study found that the effect of contaminants in waste glass fines can be neglected when being used as a replacement for natural sand at 10 wt%.

2019/20 Australia's bushfire season (Black Summer fires) occurred during a period of record breaking temperatures and extremely low rainfall. To understand the impact of these climatic values we conducted a preliminary analysis of the 2019/20 bushfire season and compared it with the fire seasons between March 2000 and March 2020 in the states of New South Wales (NSW), Victoria, and South Australia (SA). Forest and fire management in Australia were asked to provide data on the number of fires, burned area, life and house loss, as well as weather conditions. By March 2020 Black Summer fires burnt almost 19 million hectares, destroyed over 3,000 houses, and killed 33 people. Data showed that they were unprecedented in terms of impact on all areas. A number of mega-fires occurred in NSW resulting in more burned area than in any fire season during the last 20 years. One of them was the largest recorded forest fire in Australian history. Victoria had a season with the highest number of fires, area burned, and second highest numbers of houses lost for the same period. SA had the highest number of houses lost in the last 20 years. Black Summer fires confirmed existing trends of impact categories during the last two decades for NSW and Victoria. It showed that the smoke from the bushfires may be a significant concern in the future for the global community, as it travels to other countries and continents. Based on preliminary data, it will take many years to restore the economy and infrastructure in impacted areas, and to recover animal and vegetation biodiversity.

Abstract The complex cellular structure of trabecular bone possesses lightweight and superior energy absorption capabilities. By mimicking this novel high-performance structure, engineered cellular structures can be advanced into a new generation of protective systems. The goal of this research is to develop an analytical framework for predicting the critical buckling load, Young’s modulus and energy absorption of a 3D printed bone-like cellular structure. This is achieved by conducting extensive analytical simulations of the bone-inspired unit cell in parallel to traverse every possible combination of its key design parameters. The analytical framework is validated using experimental data and used to evolve the most optimal cellular structure, with the maximum energy absorption as the key performance criterion. The design charts developed in this work can be used to guide the development of a futuristic engineered cellular structure with superior performance and protective capabilities against extreme loads.

BackgroundVietnam is one of the first low- to middle-income countries to develop and implement a national-scale electronic immunization registry. This system was finalized into the National Immunization Information System (NIIS) and scaled up to a national-level system in 2017. As a result, immunization coverage and the timeliness of vaccinations have drastically improved. The time spent on planning and reporting vaccinations has drastically reduced; as a result, vaccination planning and reporting has become more accurate and effective. However, to date, end users have been tasked with managing both the NIIS and paper-based systems in parallel until a formal assessment of the readiness to fully transition to the NIIS is conducted. ObjectiveThis study aims to evaluate the readiness to move to an entirely digital NIIS in 2 provinces of Vietnam—Ha Noi and Son La. MethodsAll health facilities were surveyed to assess their infrastructure, capacity, and need for human resources. NIIS end users were observed and interviewed to evaluate their NIIS knowledge and skill sets. Data from immunization cards and facility paper-based logbooks were compared with data from the NIIS, and vaccine stocks at selected facilities were tallied and compared with data from the NIIS. ResultsOf the 990 health facilities evaluated, most used the NIIS to enter and track immunizations (987/990, 99.7%) and vaccine stocks (889/990, 90.8%). Most had stable electricity (971/990, 98.1%), at least 1 computer (986/990, 99.6%), and ≥2 trained NIIS end users (825/990, 83.3%). End users reported that the NIIS supported them in managing and reporting immunization data and saving them time (725/767, 94.5%). Although many end users were able to perform basic skills, almost half struggled with performing more complex tasks. Immunization data were compiled from the NIIS and immunization cards (338/378, 89.4%) and paper-based logbooks (254/269, 94.4%). However, only 54.5% (206/378) of immunization IDs matched, 57% (13/23) of Bacillus Calmette-Guérin vaccination records were accurate, and 70% (21/30) of the facilities had consistent physical vaccine stock balances. The feedback received from NIIS end users suggests that more supportive supervision, frequent refresher training for strengthening their skill sets, and detailed standardized guides for improving data quality are needed. ConclusionsThe readiness to transition to a digital system is promising; however, additional resources are required to address the timeliness, completeness, and accuracy of the data.

In recent decades, considerably greater flood losses have increased attention to flood risk evaluation. This study used data-sets collected from Queensland flood events and investigated the predictive capacity of three new Australian flood loss models to assess the extent of physical damages, after a temporal and spatial transfer. The models’ predictive power is tested for precision, variation, and reliability. The performance of a new Australian flood loss function was contrasted with two tree-based damage models, one pruned and one un-pruned. The tree-based models are grown based on the interaction of flood loss ratio with 13 examined predictors gathered from flood specifications, building characteristics, and mitigation actions. Besides an overall comparison, the prediction capacity is also checked for some sub-classes of water depth and some groups of building-type. It has been shown that considering more details of the flood damage process can improve the predictive capacity of damage prediction models. In this regard, complexity with parameters with low predictive power may lead to more uncertain results. On the other hand, it has also been demonstrated that the probability analysis approach can make damage models more reliable when they are subjected to use in different flooding events.

In current blast enhancement design strategies, to resist the effects of an accidental explosion, a facade system is commonly designed to behave in-elastically and undergo large deformations. The large deformation of the facade system leads to high blast energy dissipation, subsequently reducing the blast energy transferred to the main structure. In addition to the blast resistance of the facade system, human injuries due to glass fragmentation within the vicinity of the facade system should also be minimized in order to meet the required safety levels. Overall building safety can be optimized by balancing blast energy dissipation and glass fragmentation. Recently, Permasteelisa Group has developed an innovative design tool to optimize blast-enhanced facades using an equivalent MDOF approach. A novel fragmentation tool has been proposed to assist this design procedure. This paper presents various critical parameters considered in blast-enhanced facade analysis, the experimental validation of these parameters and their influence in the design optimization process.

In current blast enhancement design strategies, to resist the effects of an accidental explosion, a facade system is commonly designed to behave in-elastically and undergo large deformations. The large deformation of the facade system leads to high blast energy dissipation, subsequently reducing the blast energy transferred to the main structure. In addition to the blast resistance of the facade system, human injuries due to glass fragmentation within the vicinity of the facade system should also be minimized in order to meet the required safety levels. Overall building safety can be optimized by balancing blast energy dissipation and glass fragmentation. Recently, Permasteelisa Group has developed an innovative design tool to optimize blast-enhanced facades using an equivalent MDOF approach. A novel fragmentation tool has been proposed to assist this design procedure. This paper presents various critical parameters considered in blast-enhanced facade analysis, the experimental validation of these parameters and their influence in the design optimization process.

Prestressed concrete sleepers (PCSs) play an essential role in structural response and performance of ballasted railway tracks. Due to defects in track or train components, high magnitude dynamic loads may generate at the rail head and transfer to the PCSs which can generate cracks in PCSs. Cracking from dynamic loads have been reported as the most critical problem of PCSs around the world and impose an early replacement of sleepers which is a financial burden to the rail industry. This paper investigates the effects of strain rates on the strength enhancement of PCS. By using available measurements, the strain rates are calculated at two critical points of the PCSs, the rail seat and midspan. Considering the dynamic increase factor (DIF) of concrete, the cracking loads of a PCS are calculated and are compared with commonly occurring dynamic loads. Results show that the maximum strain rates at both rail seat and midspan are about 0.08 and 0.016 1/s, respectively. The increase of cracking wheel load due to the strain rate effects is about 5 to 26 percent. The results are also shown to be able to demonstrate the level cracking from dynamic loads with very short return periods.

This paper presents a novel damage detection method based on the reconstructed phase space of vibration signals using a single sensor. In this approach, a moving mass is applied as excitation source, and the structure vibration responses at different positions are measured using a single sensor. A Moving Filter Function (MFF) is also presented to be used to separate and filter the responses before phase space reconstruction. Using the determined time delay and embedding dimensions, the responses are translated from time domain into the spatial domain. The index CPST (changes of phase space topology) values are calculated from the reconstructed phase space and used to identify structural damage. To demonstrate the method, six analysis scenarios for a beam-like structure considering the moving mass magnitude, damage location, the single sensor location, moving mass velocity, multiple types of damage, and the responses contaminated with noise are calculated. The acceleration and displacement responses are both used to identify the damage. The results indicate that the proposed method using displacement response is more sensitive to damage than that of acceleration responses. The results also proved that the proposed method can use a single sensor installed at different location of the beam to locate the damage/much damage reliably, even though the responses are contaminated with noise.

Volumetric prefabricated building construction is growing in most developed countries; for example, in Sweden the market share of prefabricated building systems in the housing industry was more than 80%. However, in Australia only approximately 3⁻4% of new building constructions are prefabricated buildings in a year. A major hindrance to the growth of prefab construction in Australia is that systems are developed under commercial and confidential conditions. There are limited publicly-available research and case studies for certifiers, regulators, engineers and academia to provide independent information on the performance, advantages and disadvantages of prefabricated building systems. Independent designers and structural engineers are relying on the strength of the structural and non-structural element, as well as the connections of the prefabricated building systems. This strength is estimated from the “commercial-in-confidence„ test of individual components by manufactures, and it might result in undesired outcomes in design. This paper provides an overview of available literature on structural performance, benefits, constraints and challenges of prefabricated building systems. This paper also highlights the research needed on the prefabricated building systems such as full-scale tests, numerical modelling, hybrid simulations, case studies and social and economic assessments. Being supported by sound academic research will increase the market demand for prefabricated building systems in Australia as well as in other countries.

Building façades are considered as one of the critical elements of a buildings especially in case of fire where poor performance façades lead to severe fire spread and building damage including human loss. There has been a significant improvement in façade design to ensure excellent building performance in terms of energy efficiency and requirements on aesthetic appeal. These changes fundamentally alter the behaviour of modern façades in fire and pose a risk to building safety and economic loss in the event of a fire. The latest incident at Grenfell tower demonstrated how vulnerable modern facades may be to fires, and emphasised how this vulnerability directly affects the safety of building occupants. The paper provides the first comprehensive review of current international design guidelines and test methods involving fire resistive design of facades. The influence of cladding material, geometry of the façade, cavities, wind and space between buildings are also discussed. Test methods that can be used to predict the flame and smoke spread are introduced and compared comprehensively. Critical aspects as the combustibility of the materials, and further studies on façade performance in fire are also highlighted.

ABSTRACT The Arenaviridae are enveloped, negative-sense RNA viruses with several family members that cause hemorrhagic fevers. This work provides immunofluorescence evidence that, unlike those of New World arenaviruses, the replication and transcription complexes (RTC) of lymphocytic choriomeningitis virus (LCMV) colocalize with eukaryotic initiation factor 4E (eIF4E) and that eIF4E may participate in the translation of LCMV mRNA. Additionally, we identify two residues in the LCMV nucleoprotein (NP) that are conserved in every mammalian arenavirus and are required for recombinant LCMV recovery. One of these sites, Y125, was confirmed to be phosphorylated by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). NP Y125 is located in the N-terminal region of NP that is disordered when RNA is bound. The other site, NP T206, was predicted to be a phosphorylation site. Immunofluorescence analysis demonstrated that NP T206 is required for the formation of the punctate RTC that are typically observed during LCMV infection. A minigenome reporter assay using NP mutants, as well as Northern blot analysis, demonstrated that although NP T206A does not form punctate RTC, it can transcribe and replicate a minigenome. However, in the presence of matrix protein (Z) and glycoprotein (GP), translation of the minigenome message with NP T206A was inhibited, suggesting that punctate RTC formation is required to regulate viral replication. Together, these results highlight a significant difference between New and Old World arenaviruses and demonstrate the importance of RTC formation and translation priming in RTC for Old World arenaviruses. IMPORTANCE Several members of the Arenaviridae cause hemorrhagic fevers and are classified as category A pathogens. Arenavirus replication-transcription complexes (RTC) are nucleated by the viral nucleoprotein. This study demonstrates that the formation of these complexes is required for virus viability and suggests that RTC nucleation is regulated by the phosphorylation of a single nucleoprotein residue. This work adds to the body of knowledge about how these key viral structures are formed and participate in virus replication. Additionally, the fact that Old World arenavirus complexes colocalize with the eukaryotic initiation factor 4E, while New World arenaviruses do not, is only the second notable difference observed between New and Old World arenaviruses, the first being the difference in the glycoprotein receptor.

This paper presents experimental studies of concrete façade response to blast pressures. The experimental program also aims to establish the influence of fixings assemblies on the performance of precast concrete façade panels. The current standardized approach of pre-cast concrete design as defined in UFC3-340-02 limits the support fixity of pre-cast wall panels to be a simply supported system. The restriction to a simply supported system in a pre-cast wall panel would lead to inefficient design due to non-optimized use of concrete panel thickness. The experimental results showed that varying fixing assemblies may lead to a partial fixity condition, which is not accounted for in the UFC3-340-02 design guideline. The partial fixity conditions observed in the experimental results indicate that there are residual capacities in the pre-cast façade systems. The efficacy of the façade panel system could be improved by taking into account partial fixity in the support system. Similarly, premature shear failure could also be prevented by understanding the additional contribution of the partial fixity on fixing assemblies.

Spalling of concrete in fire is due to dislodgement of small pieces of concrete. This phenomenon is one of the most detrimental effects causing damage or even failure of the concrete members during or after a fire by decreasing the residual mechanical properties and durability of the structure. In spite of many experimental and numerical studies, the real mechanism of spalling is still not well understood, which is mainly due to the erratic nature of this phenomenon and inhomogeneity of the concrete structures. To establish a more clear view of the achievements in this area and also the areas in need of more investigations, this paper critically reviews the latest findings on concrete performance during heating in general and specifically the fire spalling behaviour of concrete members and different views on governing factors that affect this phenomenon.

The development of non-load bearing curtain walling technology around the turn of the 20th centre along with the effects to reduce the energy consumption of the building and dependence on artificial lightening, as well as the development of high performance glass and efficient building systems has seen architectural trends to move toward maximising glass surface areas in order to optimise natural daylight. This present study shows the potential offaçade systems potential to become an energy absorber of wind-induced vibrations. The façade has been rarely considered or designed as a potential wind-induced vibration absorber for tall buildings in the past. In this paper the potential of utilizing a moveable exterior façade in a double-skin façade is investigated and shown that with optimal choices of materials for stiffness and damping of brackets connecting the two skins, a substantial portion of wind-induced vibration energy can be dissipated which leads to avoiding expensive lateral stiffening systems and/or space consuming large damper systems such as tuned mass or liquid dampers. The work has demonstrated that up to 50% of response caused by winds can be absorbed by a smart and efficient façade design, including purely passive systems with constant stiffness and damping or better, by a smart a system possessing variable stiffness for different phases of façade movement.

Blast events can lead to critical injuries along with heavy casualties in addition to disastrous structural failure, thereby giving rise to detrimental economic and social impacts, both domestically as well as internationally. Bridges, an integral component of a vibrant transportation network, are not only vulnerable to accidental incidents, but also susceptible to deliberate attacks. Blast engineering regarding civil infrastructure, although very crucial in this modern era, has only received rapidly evolving interest in recent time, and many areas in this field, including most of the aspects regarding bridges, demand intensive attention. A state-of-theart review of the previous blast research projects concerning bridges is presented in this paper. The simplistic and advanced theoretical and practical investigation strategies employed are explained, and the distinct assumptions and justifications adopted are highlighted. The blast consequences observed on the individual bridge elements considered are described together with the subsequent impact on the overall integrity of the corresponding bridge systems. The mitigation tactics proposed are discussed, with major emphasis on the functions delivered as well as the inherent effectiveness. Further enquiries to be carried out for the future development of this engineering discipline are also identified.

Prestressed concrete sleepers (PCSs) are the most commonly used type of sleepers. They play an essential role in track performance, behaviour and safety. The focus of the published literature on PCSs has primarily been on quantification of dynamic load and resulting structural behaviour of sleepers, interaction with other components of track and failure mechanisms. While structural performance of PCSs is very important and researched as reflected by the large volume of published literature, concrete sleepers also need to meet the durability requirements. It is known that only a small percentage of concrete sleepers remain in service when reaching their intended design life, resulting in heavy maintenance and replacement costs. This paper reports a summary of the review of literature conducted as part of a broader investigation undertaken at the University of Melbourne. The aim of the investigation is to establish the material requirements of the concrete sleepers in order to meet the structural and durability requirements. A summary of the latest works on dynamic responses (including natural frequencies and mode shapes, damping, bending moments and strain rates), failure modes, fatigue and durability aspects of PCSs are presented. Moreover, design approach and dynamic loads are discussed briefly. It is established that a comprehensive research with a focus on material characterisation for concrete sleepers is currently lacking.

Despite being intensely studied for more than 50 years, a complete understanding of the enterovirus replication cycle remains elusive. Specifically, only a handful of cellular proteins have been shown to be involved in the RNA replication cycle of these viruses. In an effort to isolate and identify additional cellular proteins that function in enteroviral RNA replication, we have generated multiple recombinant polioviruses containing RNA affinity tags within the 3′ or 5′ noncoding region of the genome. These recombinant viruses retained RNA affinity sequences within the genome while remaining viable and infectious over multiple passages in cell culture. Further characterization of these viruses demonstrated that viral protein production and growth kinetics were unchanged or only slightly altered relative to wild type poliovirus. However, attempts to isolate these genetically-tagged viral genomes from infected cells have been hindered by high levels of co-purification of nonspecific proteins and the limited matrix-binding efficiency of RNA affinity sequences. Regardless, these recombinant viruses represent a step toward more thorough characterization of enterovirus ribonucleoprotein complexes involved in RNA replication.

A two dimensional behavioral rate dependent lattice model (RDLM) capable of analyzing reinforced concrete members subjected to impulsive loading is presented. As a result of the impulsive loads reaching their peak intensity in extremely short durations of time, material nonlinearities and strain rate effects play an important role in the analysis. A numerical approach based on an explicit finite element formulation is introduced to solve two dimensional planar structural problems under impulsive loads. The procedure incorporates equilibrium and compatibility conditions and utilizes realistic rate dependent stressstrain relationships for cracked concrete. The model inherently takes into account some major influencing factors, progressive cracking of concrete in tension, the inelastic response in compression, the yielding of reinforcing steel, and strain rate sensitivity of concrete and steel. Correlation studies between analytical and experimental results on reinforced concrete beams subject to impulsive loading are conducted and are shown to be in good agreement.

This paper provides a brief overview of the seismic activities in Vietnam. In the past, Vietnam did not have its own earthquake code. A new earthquake code which was based on Eurocode has been issued in 2006. The new earthquake code for Vietnam is reviewed in this paper. Due to the lack of historical records the establishment of the local site factors and design seismic response spectrum for major cities in Vietnam was found problematic. A case study was carried out to determine the full range response spectra for seismic design of building structures in Hanoi, the capital city of Vietnam. The study comprises the following components: (i) development of a seismic activity model for the potential earthquake sources in the region surrounding Hanoi; (ii) the response spectrum modelling for rock sites based on the assumed seismic activity; (iii) soil amplification modelling to represent typical soil conditions in Hanoi. Several representative boreholes have been obtained for soil resonance analyses based on the predicted bedrock motion. This method has been found very useful to produce important seismic parameters for earthquake design.

The use of vehicle bombs to attack city centers has been a feature of campaigns by terrorist organizations around the world. A bomb explosion within or immediately nearby a building can cause catastrophic damage on the building's external and internal structural frames, collapsing of walls, blowing out of large expanses of windows, and shutting down of critical life-safety systems. Loss of life and injuries to occupants can result from many causes, including direct blast-effects, structural collapse, debris impact, fire, and smoke. The indirect effects can combine to inhibit or prevent timely evacuation, thereby contributing to additional casualties. In addition, major catastrophes resulting from gas-chemical explosions result in large dynamic loads, greater than the original design loads, of many structures. Due to the threat from such extreme loading conditions, efforts have been made during the past three decades to develop methods of structural analysis and design to resist blast loads. The analysis and design of structures subjected to blast loads require a detailed understanding of blast phenomena and the dynamic response of various structural elements. This paper presents a comprehensive overview of the effects of explosion on structures. An explanation of the nature of explosions and the mechanism of blast waves in free air is given. This paper also introduces different methods to estimate blast loads and structural response.

Simple quasi-static treatment of wind loading, which is universally applied to design of typical low to medium-rise structures, can be unacceptably conservative for design of very tall buildings. On the other hand such simple treatment can easily lead to erroneous results and under-estimations. More importantly such a simplified treatment for deriving lateral loads does not address key design issues including dynamic response (effects of resonance, acceleration, damping, structural stiffness), interference from other structures, wind directionality, and cross wind response, which are all important factors in wind design of tall buildings. This paper provides an outline of advanced levels of wind design, in the context of the Australian Wind Code, and illustrates the exceptional benefits it offers over simplified approaches. Wind tunnel testing, which has the potential benefits of further refinement in deriving design wind loading and its effects on tall buildings, is also emphasized.

Compact Reinforced Composite, CRC, is a high-strength cement-based composite possessing an enormous flexural and energy-absorbing capacity due to close-spaced high strength steel reinforcement and a high-strength cement-based fiber DSP matrix. The material has been used in various construction projects including as protection for explosion hazards. In connection with explosive impact, the fraction of shear reinforcement needed to obtain full flexural capacity is controlled by the stand-off distance. For close-in detonations, a high fraction of shock reinforcement is needed to obtain full flexural capacity without breaching. This paper introduces an efficient method for implementing high fractions of polymer shock reinforcement into a CRC element. Experimental tests and a preliminary finite element analysis were performed to assess the potency of this material.

This article discusses the changes in tall building design practice after the World Trade Centre (WTC) buildings collapse. Although many suggestions were made post-9/11, regarding the improvement of the performance of buildings, no major changes have yet been implemented. These suggestions and the lessons learnt from the collapse are discussed in the paper.

Existing knowledge on the modelling of blast pressure have been further developed in this paper for engineering applications. Parametric studies involving time-history analyses of simple cantilevered wall models have been undertaken based on pre-defined pressure functions to study basic trends. The "corner period" of the velocity response spectrum was found to be the key controlling parameter in response behaviour modelling of the walls. An important contribution from this study is the identification of the direct relationship between the corner period and the "clearing time" for the blast. A simple and yet realistic capacity spectrum model has been developed for the design and assessment of cantilevered walls for its performance under blast loads. The practicality of the proposed model has been demonstrated herein by a worked example.

The use of high-strength concrete in reinforced concrete slabs is becoming popular in Australia and other countries. Current design provisions of AS3600 and other major codes throughout the world are based on empirical relationships developed from tests on low-strength concrete. In this paper, the experimental results from 4 research studies are used to review the existing recommendations in design codes for punching shear failure of slabs. Design codes referred in this study are AS3600 and CEB-FIP MC 90. In AS3600 the punching shear strength is expressed as proportional to fc1/2. However in CEB-FIP MC 90 punching shear strength is assumed to be proportional to fc1/3. It is shown that the present provisions in AS3600 are applicable up to 100 MPa.