Key Design Criteria Research Articles

Decoding the Molecular Basis for the Population Mechanism of the Triplet Phototoxic Precursors in UVA Light-Activated Pyrimidine Anticancer Drugs.

The photosensitization of DNA by thionucleosides is a promising photo-chemotherapeutic treatment option for a variety of malignancies. DNA metabolization of thionated prodrugs can lead to cell death upon exposure to a low dose of UVA light. The exact mechanisms of thionucleoside phototoxicity are still not fully understood. In this work, we have combined femtosecond broadband transient absorption experiments with state-of-the-art molecular simulations to provide mechanistic insights into the ultrafast and efficient population of the triplet state in the UVA-activated pyrimidine anticancer drug 4-thiothymine. The triplet state is thought to act as a precursor to DNA lesions and the reactive oxygen species responsible for 4-thiothymine photocytotoxicity. The electronic-structure and mechanistic results presented in this contribution reveal key molecular design criteria that can assist in developing alternative chemotherapeutic agents that may overcome some of the primary deficiencies of classical photosensitizers.

Ecological considerations in sustainable silvopasture design and management

Silvopastoral systems are sustainable production systems characterized by greater biodiversity and multifunctionality, compared with other livestock production methods. The complex functional dynamics, however, make silvopastoralism a difficult construct to design and study. The key design criterion for these complex land use practices is to optimize the use of spatial, temporal, and physical resources, by maximizing positive interactions (facilitation) and minimizing negative ones (competition) among the components, for which the principles of sustainable land use systems are relevant. In this paper we address the cardinal questions, how the general ecological principles common to complex natural systems apply to the design and management of silvopastoral systems and how sound management might be identified with the notion of sustained maximum yield. In particular, we explore (1) spatial and temporal heterogeneity for maximizing resource use efficiency, (2) competitive interactions in perennial systems, (3) structural and functional diversity for resource conservation, and (4) integration of the principles of disturbance ecology in silvopastoral system design.

Multiple rainfall event pollution transport by sustainable drainage systems: the fate of fine sediment pollution

A key design criterion of sustainable urban drainage systems is to mitigate urban stormwater pollution. Current research defines sustainable urban drainage systems (SuDS) pollutant treatment efficiency through the detention of total suspended solids, urban nutrients and heavy metal pollutants within the system during a design flow event, with research focusing on sand (>2 mm) sediment movement. The impact of multiple rainfall–runoff events on the fine sediment (<2 mm) treatment efficiency of SuDS is not yet well defined, and the temporal movement of detained sediment has not been investigated in detail. The field research presented in this paper addresses this research gap, monitoring ongoing fine sediment transport through a best-practice-designed SuDS network over 12 months through the use of a novel rare earth oxide trace methodology. Through time-stepped monitoring of the fine sediment pollution across three SuDS treatment trains (networks), the following key conclusions have been drawn. (1) That fine sediment becomes re-suspended and re-deposited within SuDS assets and the network as a result of ongoing multiple rainfall–runoff events. (2) That this re-suspension continues for over 52 weeks. (3) That by area, linear wetlands (within the monitored networks) outperform wetland and swale assets in multiple event fine sediment detention. And (4) that multiple event monitoring and analysis of fine sediment within a SuDS network highlights the under-performance of SuDS assets against current design event expectations.

Design, Analysis and Construction of a Steel Truss Cable-Stayed Bridge for High-Speed Railway in China

The Yujiang cable-stayed bridge, a significant project of the Nanning–Guangzhou High-Speed Railway, consists of steel-truss girders and two symmetrical vase-shaped concrete pylons up to 102.5 m high. With a main span of 228 m, the bridge crosses the main shipping channel of the Yujiang River. In this paper, the key design criteria and structural details are reviewed and discussed along with the special design considerations, including pylon local stress distribution, vehicle–bridge interaction, seismic response and wind tunnel experiment. In addition, a new construction method involving synchronous construction technology of tower and girder is introduced.

Unusual Dual Superlyophobic Surfaces in Oil-Water Systems: The Design Principles.

Thermodynamically unusual surfaces that possess two contradictory wetting properties, i.e., underoil superhydrophobicity and underwater superoleophobicity, are prepared by the combination of re-entrant topography and delicately matched surface chemistry. The preparation of such extraordinary surfaces relies on two key design criteria and employs a metastable state effect in solid-oil-water systems.

Open-source predictive simulators for scale-up of direct contact membrane distillation modules for seawater desalination

Proper industrial-scale module design for seawater desalination by means of direct contact membrane distillation (DCMD) can be aided by module simulation. Accordingly, two open-source simulators (of flat sheet membranes and hollow fibre membranes) were developed on the Matlab GUI platform to supplement DCMD module scale-up. A coupled “tanks-in-series” and “black box” mathematical approach was developed not only to yield accurate simulation, but also to produce profiles of all the key parameters versus membrane length. Using laboratory-scale experimental results in one configuration as simulation inputs, the developed simulators were able to predict large-scale DCMD module performance in both co-current and counter-current configurations. These predictions exhibited good accuracy in both laboratory-scale and large-scale. Design considerations informing appropriate module scale-up for the DCMD process were demonstrated using the simulators. Key design criteria for industrial-scale module design were identified and evaluated. The results presented in this study offer general and practical guidance for proper module scale-up to deliver optimal pure water productivity for industrial-scale seawater desalination using the DCMD process. More importantly, the developed simulators are open-source, available for all researchers to develop specific DCMD module scale-up strategies for their own membranes.

Engineered Biopolymeric Scaffolds for Chronic Wound Healing.

Skin regeneration requires the coordinated integration of concomitant biological and molecular events in the extracellular wound environment during overlapping phases of inflammation, proliferation, and matrix remodeling. This process is highly efficient during normal wound healing. However, chronic wounds fail to progress through the ordered and reparative wound healing process and are unable to heal, requiring long-term treatment at high costs. There are many advanced skin substitutes, which mostly comprise bioactive dressings containing mammalian derived matrix components, and/or human cells, in clinical use. However, it is presently hypothesized that no treatment significantly outperforms the others. To address this unmet challenge, recent research has focused on developing innovative acellular biopolymeric scaffolds as more efficacious wound healing therapies. These biomaterial-based skin substitutes are precisely engineered and fine-tuned to recapitulate aspects of the wound healing milieu and target specific events in the wound healing cascade to facilitate complete skin repair with restored function and tissue integrity. This mini-review will provide a brief overview of chronic wound healing and current skin substitute treatment strategies while focusing on recent engineering approaches that regenerate skin using synthetic, biopolymeric scaffolds. We discuss key polymeric scaffold design criteria, including degradation, biocompatibility, and microstructure, and how they translate to inductive microenvironments that stimulate cell infiltration and vascularization to enhance chronic wound healing. As healthcare moves toward precision medicine-based strategies, the potential and therapeutic implications of synthetic, biopolymeric scaffolds as tunable treatment modalities for chronic wounds will be considered.

Harnessing natural light for energy efficiency in buildings

This paper is written within the premise that lighting accounts for a sizeable portion of the total energy requirements of Sri Lanka. It is also noted that efficiently planned usage of daylight for building interiors could result in considerable savings in energy and thereby lead to energy efficiency. The intention of this article is to highlight few key design criteria which must be considered by architects in harnessing natural light to make the buildings they create energy efficient. Although these criteria are commonly known, lack of understanding and application are amply demonstrated in contemporary Sri Lankan buildings.

High-throughput exploration of thermoelectric and mechanical properties of amorphous NbO2 with transition metal additions

To increase the thermoelectric efficiency and reduce the thermal fatigue upon cyclic heat loading, alloying of amorphous NbO2 with all 3d and 5d transition metals has systematically been investigated using density functional theory. It was found that Ta fulfills the key design criteria, namely, enhancement of the Seebeck coefficient and positive Cauchy pressure (ductility gauge). These quantum mechanical predictions were validated by assessing the thermoelectric and elastic properties on combinatorial thin films, which is a high-throughput approach. The maximum power factor is 2813 μW m−1 K−2 for the Ta/Nb ratio of 0.25, which is a hundredfold increment compared to pure NbO2 and exceeds many oxide thermoelectrics. Based on the elasticity measurements, the consistency between theory and experiment for the Cauchy pressure was attained within 2%. On the basis of the electronic structure analysis, these configurations can be perceived as metallic, which is consistent with low electrical resistivity and ductile behavior. Furthermore, a pronounced quantum confinement effect occurs, which is identified as the physical origin for the Seebeck coefficient enhancement.

A novel predictive PCE-based protection strategy for resilient transport networks

The ever increasing requirements of new Internet applications are pushing to optimize the design of optical networks. A key design criterion in network design is the ability to recover from failures in an agile and efficient manner. Protection capabilities are highly required in optical networks since the failure of an optical link might potentially lead to a significant traffic loss. Under this context, Network Coding Protection (NCP) has emerged as an innovative solution to proactively enable protection in an agile and efficient manner by means of throughput improvement techniques such as Network Coding (NC). Nevertheless, the benefits of NC can be reduced by the negative effects of inaccurate Network State Information (NSI), which are common in dynamic scenarios.In this paper, we propose a novel proactive protection strategy based on NC jointly with a Path Computation Element (PCE) architecture called Predictive Network Coding Protection (PNCP). PNCP leverages predictive techniques in order to mitigate the negative impact of the inaccurate NSI on the blocking probability. In addition, PNCP computes resilient lightpaths with a low amount of network resources devoted for path protection.By means of extensive simulation results we show that in comparison with proactive protection strategies such as Dedicated Path Protection (DPP), and conventional dynamic NCP, PNCP reduces the blocking probability as well as the network resources allocated for path protection in dynamic scenarios.

Immunogenicity and biodistribution of nanoparticles in vivo

Abstract Nanoparticles have been widely used in vaccine design as both adjuvants and antigen delivery vehicles. In a seminal study, 40–50 nm nanoparticles with conjugated antigen were shown to induce high antibody titers and IFN-γ production in mice but with no added inflammatory stimuli. Subsequent research has shown that similar levels of immunogenicity can be achieved via the co-injection of naked 40–50 nm nanoparticles adjuvants and larger 500 nm nanoparticles with conjugated antigen. Furthermore, recent works indicate that particle shape can also influence the immune response. As such, we investigate the influence of surface morphology using 40–50 nm smooth and rough surfaced nanoparticle adjuvants and report their differential immunogenicity via ELISA, ELISpot and flow cytometry. Further, we determine the biodistribution of fluorescent 40–50 nm nanoparticle adjuvants with smooth and rough surfaces and larger 500 nm nanoparticles. Nanoparticle size is shown to be a discriminating factor in lymph node drainage, using a Carestream FX PRO in vivo imaging system and fluorescence microscopy of lymph nodes sectioned ex vivo. To elucidate the safety profile of this vaccine construct, we also investigate the biodistribution of nanoparticles within the major organs. The outcomes from this study provide key design criteria in the development of novel nanoparticle immunotherapeutics for the treatment of disease.

Systematic Variation of Sulfur Cathode Chemistry and Its Effects on Cell Performance

In recent years, tremendous effort has been invested into researching energy storage chemistries that will replace lithium ion. New strategies with higher capacities must be considered, such as a chemical conversion cathode. The lithium sulfur chemistry is a promising candidate as it uses earth abundant, inexpensive, high capacity sulfur as its cathode. Conversion cathodes like sulfur are much more challenging as a secondary battery, and behave differently than intercalation cathodes. Because of this, different design criteria must be applied to conversion cathodes to maximize power and capacity. The interplay of conductive network, insulating active cathode, and binder all give rise to differences in performance for the dissolution and precipitation of the cathode material. This work attempts to identify key design criteria for sulfur cathodes by systemically varying the basic components of cathode chemistry and structure. A matrix of ~110 different cathode formulations were fabricated by varying conducting carbon, % active material, binder system, and sulfur loading. Performance of these cathodes was evaluated by means of 2032 coin cell tests under constant current and pulsed loads. First discharge capacity, capacity retention, coulombic efficiency, impedance, cathode surface area, and cathode porosity are utilized to gauge the effectiveness of the cathode and explain trends observed in cycling tests. The effects of cathode rheology on porosity surface area and overall cathode utilization was also investigated. Observed differences in performance between different electronically conductive elements and different cathode support elements were observed, with nuanced changes in morphology resulting in significant performance changes. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000. Figure 1

Ordered Mesoporous to Macroporous Oxides with Tunable Isomorphic Architectures: Solution Criteria for Persistent Micelle Templates

Porous and nanoscale architectures of inorganic materials have become crucial for a range of energy and catalysis applications, where the ability to control the morphology largely determines the transport characteristics and device performance. Despite the availability of a range of block copolymer self-assembly methods, the conditions for tuning the key architectural features such as the inorganic wall-thickness have remained elusive. Toward this end, we have developed solution processing guidelines that enable isomorphic nanostructures with tunable wall-thickness. A new poly(ethylene oxide-b-hexyl acrylate) (PEO-b-PHA) structure-directing agent (SDA) was used to demonstrate the key solution design criteria. Specifically, the use of a polymer with a high Flory–Huggins effective interaction parameter, χ, and appropriate solution conditions leads to the kinetic entrapment of persistent micelle templates (PMT) for tunable isomorphic architectures. Solubility parameters are used to predict conditions for mai...

A hybrid approach for environmental impact evaluation of design options

The strengthened environmental regulatory requirements and general awareness of the need for environmental conservation worldwide, design for environment has become a key design criterion in new product development processes. Due to their resources-consuming attribute and the prerequisite expert knowledge in environmental sciences for the impacts interpretations, the existing forms of product-oriented environmental impact assessment methods are impractical to be adopted by product designers in small-and-medium enterprises. Life Cycle Assessment (LCA) is a generally accepted quantitative approach to assess a product’s environmental impact. However, a full LCA study often requires a considerable amount of data and therefore, it is regarded as not a handy tool for product design evaluations particularly at the initial design stage. This leads to our intention to develop an immediately applicable approach for decision-makers to evaluate the design options. The proposed approach integrates Analytic Hierarchy Process and Fuzzy Theory, with Evidential Reasoning (ER) to support the environmental impact evaluations of design options. A case study is carried out to demonstrate its applicability to prioritize the environmental impact of various design options. A symmetrical triangular distribution is introduced for calculating the expected utility and for testing the sensitivity of results.

Sum-rate maximisation for two-way AF MIMO relaying networks and random antenna selection

This paper considers a multiple-input multiple-output MIMO two-way relaying network, where two-source nodes exchange data via a half-duplex amplify-and-forward AF relay. In this paper, we propose an efficient random antenna selection strategy based on maximising the sum-rate and minimising the power consumption. The proposed strategy involves choosing the best transmit and receive antennas at the two sources based on the maximisation of the overall sum-rate. The key design criterion is to reduce transmit radio frequency chains in order to minimise the energy consumption of the system. In the first step, transmit and receive antennas will be selected randomly. In the second step, signal-to-noise ratios SNRs of randomly chosen antennas are compared with a predefined threshold γ

Differential antibody induction to surface textured silica nanoparticle adjuvants (VAC3P.1055)

Abstract Nanoparticles have been shown to be a potent adjuvant in vaccine design. Previous studies demonstrated that carboxylated 40-50 nm polystyrene nanoparticles (PSNPs) with covalently bound antigen offer a new class of vaccine with only two elements (antigen and particle) but with no added inflammatory stimuli. Herein, we report on a deconstructed two-part vaccine whereby the adjuvant and protein carrier are co-administered to elicit potent antibody responses in vivo. Recent works indicate that particle shape can also influence the immune response. As such, we investigate the influence of surface morphology using smooth and rough surfaced silica nanoparticle adjuvants, showing smooth nanoparticles as the more potent antibody inducers. MTT assay confirms that both silica nanoparticle adjuvant and polystyrene protein carrier display excellent biocompatibility with over 95% viability with COS-7 cells. Preliminary in vitro dendritic cell (DC) culture experiments indicate that silica nanoparticle adjuvants, similarly to PSNPs, do not induce the up-regulation of maturation markers, CD80, CD86 and MHC II on CD11c+ gated DCs. This suggests the particle carrier itself is non-inflammatory, a required feature for our vaccine approach. Ongoing studies are focusing on the cytokines induced in vitro and in vivo by these novel constructs. The outcomes from this study provide key design criteria in the development of novel nanoparticle immunotherapeutics for the treatment of disease.

Torrent Frog‐Inspired Adhesives: Attachment to Flooded Surfaces

Anatomic differences on the toe pad epithelial cells of torrent and tree frogs (elongated versus regular geometry) are believed to account for superior ability of torrent frogs to attach to surfaces in the presence of running water. Here, the friction properties of artificial hexagonal arrays of polydimethylsiloxane (PDMS) pillars (elongated and regular) in the presence of water are compared. Elongated pillar patterns show significantly higher friction in a direction perpendicular to the long axis. A low bending stiffness of the pillars and a high edge density of the pattern in the sliding direction are the key design criteria for the enhanced friction. The elongated patterns also favor orientation‐dependent friction. These findings have important implications for the development of new reversible adhesives for wet conditions.

Low-Power Touch-Sensing Circuit With Reduced Scanning Algorithm for Touch Screen Panels on Mobile Devices

Touch screen panel (TSP) technology has dramatically enhanced the connectivity between man and machine, in particular within mobile consumer electronics where mobility is a key design criterion. This paper introduces a novel charge-sensing technique derived from the behavioral characteristics of a mutual capacitive touch screen panel. The approach is based on a reduced scan algorithm whereby both the target and its surroundings form the node and the selection process is conducted in two phases. In the first phase, the introduction of a charge on the TSP is sensed, while the second phase evaluates when the touch event occurs on the TSP. The proposed algorithm reduces the number of sensing nodes activated during the waiting period by observing the behavior of a single row within the charge sensing array, as opposed to the more conventional approach in which all TSP nodes are scanned. As a result, power consumption is reduced by 60% during the sensing phase, while the dynamic sensing range is increased by a factor of 38% for a complete two-stage sensing cycle.

OS1102-115 破壊モードを考慮した複合材の損傷進展解析 : その2:衝撃後に静的圧縮を受ける平板について

Compression after impact (CAI) strength is a key design criteria for composite structure. In this study, impact damage and CAI strength were simulated by progressive damage analysis. The LaRC03 failure criteria which consider fiber kink failure mode was employed for each lamina, and cohesive zone modelling was applied for interlaminar resin layer. In these analyses, impact load and static compression load were applied successively. The simulated impact damage area and CAI strength were compared to tests results. Consequently, simulation well predicted test results for both of impact damage and CAI strength. In addition, it was suggested that CAI failure is caused by fiber kink in each lamina, not by propagation of delamination.

Review of Photovoltaic/Thermal System Design and Heat Transfer Enhancement Methods

Solar energy is a viable renewable energy source, and photovoltaic technology has mature significantly in recent years. To maintain the operating efficiency of photovoltaic system, heat must be remove from its surface, thus lead to development of photovoltaic/thermal system. This paper identify several key design criteria as well as heat transfer enhancement methods that is currently existed, and some future work is proposed to optimize the system.