Simple Design Modification Research Articles

Transdermal Sensing of Enzyme Biomarker Enabled by Chemo-Responsive Probe-Modified Epidermal Microneedle Patch in Human Skin Tissue.

Wearable bioelectronics represents a significant breakthrough in healthcare settings, particularly in (bio)sensing which offers an alternative way to track individual health for diagnostics and therapy. However, there has been no notable improvement in the field of cancer, particularly for skin cancer. Here, a wearable bioelectronic patch is established for transdermal sensing of the melanoma biomarker, tyrosinase (Tyr), using a microneedle array integrated with a surface-bound chemo-responsive smart probe to enable target-specific electrochemical detection of Tyr directly from human skin tissue. The results presented herein demonstrate the feasibility of a transdermal microneedle sensor for direct quantification of enzyme biomarkers in an ex vivo skin model. Initial performance analysis of the transdermal microneedle sensor proves that the designed methodology can be an alternative for fast and reliable diagnosis of melanoma and the evaluation of skin moles. The innovative approach presented here may revolutionize the landscape of skin monitoring by offering a nondisruptive means for continuous surveillance and timely intervention of skin anomalies, such as inflammatory skin diseases or allergies and can be extended to the screening of multiple responses of complementary biomarkers with simple modification in device design.

Experimental and simulation studies on the no‐load performance assessment of a domestic solar dryer

AbstractSolar dryers have been tested with various simple and complex design modifications for better efficiencies. This article attempts to investigate the effect of a very simple design modification on the no‐load performance of a natural convection domestic solar dryer (NCDSD). A direct‐type domestic solar dryer has been developed with an air cavity surrounding the drying chamber. To compare the effect of air cavity, a domestic solar dryer without air cavity has also been developed and both the dryers were tested simultaneously under the climate of Hisar, India. The values of thermal efficiency were calculated along with convective heat transfer coefficient from absorber plate to the drying air. Both the dryers were also analyzed by developing finite element models in COMSOL multiphysics computer software. The no‐load thermal efficiency for the domestic solar dryer without and with air cavity was found to be 22.68% and 34.08%, respectively. The values of coefficient of correlation for modeled and actual drying tray temperatures for dryer without and with air cavity were 0.980466 and 0.9833917, respectively. The proposed finite element model would be helpful in the design and development of NCDSDs.

High-pressure homogenizer valve design modifications allowing intensified drop breakup without increasing power consumption. I. Optimization of current design-principle

This study uses a model-based design approach (CFD coupled to well-established emulsification correlations) to investigate how to choose the valve dimensions of a high-pressure homogenizer so as to achieve intensified drop breakup without increasing the power consumption. Results show how design modifications influence the thermodynamic efficiency of the homogenizer via two effects, a friction factor and a factor related to how high a dissipation rate of turbulent kinetic energy that the design delivers in the centre of the jet. By simple design modifications, thermodynamic efficiency can be increased by 4 % (compared to a representative contemporary valve design) by decreasing the inlet chamber angle, and an additional 5 % by carefully adjusting the outlet chamber angles so as to ensure that the jet exits the gap free of the wall, but then bends and re-attaches to the wall further downstream. The modifications are predicted to allow for achieving the same resulting drop size but with a 17 % lower power draw, compared to a standard contemporary valve, or alternatively a smaller resulting drop diameter at constant power draw.

Micropyramid-patterned, oxygen-permeable bottomed dish for high density culture of pancreatic islets

The need for maintaining cell-spheroid viability and function within high-density cultures is unmet for various clinical and experimental applications, including cell therapies. One immediate application is for transplantation of pancreatic islets, a clinically recognized treatment option to cure type 1 diabetes; islets are isolated from a donor for subsequent culture prior to transplantation. However, high seeding conditions cause unsolicited fusion of multiple spheroids, thereby limiting oxygen diffusion to induce hypoxic cell death. Here we introduce a culture dish incorporating a micropyramid-patterned surface to prevent the unsolicited fusion and oxygen-permeable bottom for optimal oxygen environment. A 400 µm-thick, oxygen-permeable polydimethylsiloxane sheet topped with micropyramid pattern of 400 µm-base and 200 µm-height was fabricated to apply to the 24-well plate format. The micropyramid pattern separated the individual pancreatic islets to prevent the fusion of multiple islets. This platform supported the high oxygen demand of islets at high seeding density at 260 islet equivalents cm−2, a 2–3-fold higher seeding density compared to the conventional islet culture used in a preparation for the clinical islet transplantations, demonstrating improved islet morphology, metabolism and function in a 4 d-culture. Transplantation of these islets into immunodeficient diabetic mice exhibited significantly improved engraftment to achieve euglycemia compared to islets cultured in the conventional culture wells. Collectively, this simple design modification allows for high-density cultures of three-dimensional cell spheroids to improve the viability and function for an array of investigational and clinical replacement tissues.

Investigating the Effect of Rotor Design Changes on Mechanical Losses Due to Rotor-Fluid Interaction

Abstract The overall efficiency of high-speed rotating machines depends largely on their mechanical efficiency. Mechanical efficiency is not just a matter of bearing losses, but includes all interactions of the rotor with the environment. Analytical and empirical descriptions of turbulent or laminar flow around rotating surfaces have been used to estimate the mechanical losses of a turbocharger rotor based on geometric parameters and operating conditions. Based on the knowledge of the effect of each parameter, design changes to the rotor were proposed. The positive effect of simple design modifications on mechanical losses was experimentally verified by measurements on a test turbocharger.

Effect of inlet chamber design and operation conditions on laminar drop deformation in a production-scale high-pressure homogenizer—A hydrodynamic investigation

Due to their wide utilization and low thermodynamic efficiency, there is a large interest in designing more efficient high-pressure homogenizer valves. Drop breakup in these devices is by turbulent interaction downstream of the gap exit. However, recent investigations in scaled systems suggest that the drops can be ‘primed’ for breakup by elongation upstream of the gap entrance. This study uses hydrodynamic modelling to investigate (1) if this effect is expected in production-scale valves and (2) if it can be enhanced by simple design modifications. Results confirm the high velocity gradients formed upstream of the gap (and proposes a model for estimating them based on design and operating conditions). However, regardless of which of the three deformation/relaxation models that is applied, no sizable drop deformation is predicted at the gap exit under standard conditions (e.g., in dairy processing, the single largest application). The drops are too small to deform substantially. Under extreme conditions (higher pressures, flowrates and inlet angles, and shorter gaps), a lightly deformed drop exits the gap. However, when taking into account the constraints set by applications, energy cost and valve manufacturing, no sizable deformation is possible to achieve by simple design modifications to the inlet chamber.

From laminar to turbulent flow in a dry powder inhaler: The effect of simple design modifications

In order to better understand powder dispersion in dry powder inhaler (DPI) devices, a new powder disperser was designed, which uses flow modifiers to alter powder fluidization behavior so as to physically replicate various flow conditions observed in a range of commercial DPIs. The influence of these modifiers on the performance of the DPI was analyzed for flowrates progressing from laminar (15 L/min) to transitional (30 L/min), and finally turbulent flow regimes (60 L/min) in the device. The aerosol performance of the disperser was measured using a Next Generation Impactor. For flowrate in the laminar regime, powder evacuation from the disperser was generally insufficient (<30%), which was increased to >85% when the device was operated in the turbulent flow regime. In contrast, the highest fine particle fraction (FPF) and lowest throat deposition were achieved when operating in the transitional flow regime. The FPF could be increased further by applying flow modifications such as narrowing the air passage before the powder pocket, inducing localized turbulence (by a grid) near the powder pocket, and by changing the loading position of the powder. Flow modifiers had the most noticeable effect under a laminar flow regime, however, the device operated most efficiently under a transitional flow regime.

3D investigation of semi-underground room comfort in a desert climate

In Algeria, the residential sector registries a high rate of energy consumption which requires an important action for rationalizing this charge and integrating renewable energies. Partic- ularly, the geothermal energy with its less intermittence presents an attractive candidate to reinforce energy-saving and building thermal comfort. In this paper, geothermal energy is used to create a favorable environment for creating a better life inside a semi-buried build- ing during the very hot period in the desert climate of southern Algeria. The cooled room is buried in rocky soil until 3 m depth, and only 0.5 m of the room high is above the ground level. The upper parts of southern and northern room walls are provided by small windows for aeration and lighting purposes. Inside room the air flow is modeled by Navier-Stocks and energy equations. The computational domain is taken as 3D design, and the prediction of temperature is calculated by ANSYS-Fluent code. For the base case, at 2 m height, the indoor temperature fluctuates between 30 and 33°C which is in good concordance with experimental data. For reducing the indoor temperature, some simple design modifications are introduced and a small ventilation system is installed. The new results show that the indoor temperature does not exceed 25 °C at the height of 2 m, therefore the temperature for height between 2 and 3 m it fluctuates between 25 and 26 °C. This indoor thermal behavior ensures acceptable cooling with negligible electricity consumption.

3D Printing of Tunable Zero-Order Release Printlets.

Zero-order release formulations are designed to release a drug at a constant rate over a prolonged time, thus reducing systemic side effects and improving patience adherence to the therapy. Such formulations are traditionally complex to manufacture, requiring multiple steps. In this work, fused deposition modeling (FDM) 3D printing was explored to prepare on-demand printlets (3D printed tablets). The design includes a prolonged release core surrounded by an insoluble shell able to provide zero-order release profiles. The effect of drug loading (10, 25, and 40% w/w paracetamol) on the mechanical and physical properties of the hot melt extruded filaments and 3D printed formulations was evaluated. Two different shell 3D designs (6 mm and 8 mm diameter apertures) together with three different core infills (100, 50, and 25%) were prepared. The formulations showed a range of zero-order release profiles spanning 16 to 48 h. The work has shown that with simple formulation design modifications, it is possible to print extended release formulations with tunable, zero-order release kinetics. Moreover, by using different infill percentages, the dose contained in the printlet can be infinitely adjusted, providing an additive manufacturing route for personalizing medicines to a patient.

Shorter trawls improve size selection of northern shrimp

Discards of small northern shrimp (Pandalus borealis) are a problem in the Skagerrak northern shrimp trawl fishery. To reduce catches of small shrimp, we studied the effect of trawl belly length on size selectivity in November 2017 and June 2018 onboard 15 and 27 m double-rigged shrimp trawlers. The selectivity of the vessels’ standard trawl was compared with a trawl differing only in the belly length, being 37% shorter. The trawls had 40 mm bottom panels and cod ends of 35 mm mesh sizes. Eleven and 14 hauls were made, respectively, in 2017 aboard the 15 m vessel and in 2018 aboard the 27 m vessel. The trawls fished shrimp above 19 mm carapace length equally, while catch rates of shrimp below 15.5–16 mm carapace length in the shorter trawl were more than halved. The results were consistent between the two vessels. In short, modifying trawl length is a simple design modification that can reduce catches of small shrimp. Bycatch of Norway pout (Trisopterus esmarkii) was slightly reduced in the shorter trawl, unrelated to fish length.

Study and Analysis of ENCON Opportunities in Automatic Tube Filling Machine

In this paperentitled, “Study and analysis of ENCON opportunities in Automatic Tube Filling Machine,” In this machine the plastic tubes gets sealed and aluminum tubes gets folded at open end. Wehave plannedto study and design mechanical cam based folding operation which will reduce the operating cost of the machine. We are going to study the folding operation in traditional Automatic tube filling machine. The traditional Automatic tube filling machine has pneumatically operated folding mechanism due to which operating cost of the machine increases. Using mechanical energy and cam principle we can operate the tube folding mechanism[4]. Simple modification in design will operates the tube folding mechanism without changing the main motor consumption.

Analysis of pre-service physics teacher skills designing simple physics experiments based technology

Pre-service physics teacher skill in designing simple experiment set is very important in adding understanding of student concept and practicing scientific skill in laboratory. This study describes the skills of physics students in designing simple experiments based technologicall. The experimental design stages include simple tool design and sensor modification. The research method used is descriptive method with the number of research samples 25 students and 5 variations of simple physics experimental design. Based on the results of interviews and observations obtained the results of pre-service physics teacher skill analysis in designing simple experimental physics charged technology is good. Based on observation result, pre-service physics teacher skill in designing simple experiment is good while modification and sensor application are still not good. This suggests that pre-service physics teacher still need a lot of practice and do experiments in designing physics experiments using sensor modifications. Based on the interview result, it is found that students have high enough motivation to perform laboratory activities actively and students have high curiosity to be skilled at making simple practicum tool for physics experiment.

Designed habitat heterogeneity on green roofs increases seedling survival but not plant species diversity

Abstract Urban areas benefit from the ecosystem services provided by low input green roofs. However, limited substrate depth on these green roofs creates challenging conditions for plant establishment and survival, leading to industry reliance on non‐native succulents. Through a green roof and glasshouse study, we assessed the impact of simple design modifications to the green roof surface, including redistribution of substrate and addition of logs and pebble piles, on both substrate temperature and moisture content. We added seeds of 26 native species and quantified seedling density, species richness and composition over a single growing season. Overall effects of microsite heterogeneity on species diversity were assessed using species accumulation curves. The modifications altered substrate temperature and moisture. Deep substrate (10–12 cm) and the presence of surface features reduced the temperature by 14.6°C and, while surface features had mixed effects on substrate moisture on the green roof, pebble piles slowed moisture loss during a 6‐week drought in the glasshouse. Following drought conditions, seedling density and species richness were greatest, relative to seeded controls, where substrate was deep on the green roof and where pebbles were present in glasshouse modules, despite high mortality overall. Design modifications did not result in differentiation of seedling communities among different microsite types. Species accumulation curves showed no difference in species richness between aggregates of modified vs. unaltered microsites. Synthesis and applications. Redistribution of green roof substrate and the addition of logs and pebble piles altered microsite conditions and created habitat heterogeneity on a green roof. These design modifications represent a minimalist strategy to ameliorate growing conditions, improve seedling survival and decrease species loss on shallow substrate green roofs.

Tale of Twisted Molecules. Atropselective Photoreactions: Taming Light Induced Asymmetric Transformations through Non-biaryl Atropisomers.

Photochemical transformations are a powerful tool in organic synthesis to access structurally complex and diverse synthetic building blocks. However, this great potential remains untapped in the mainstream synthetic community due to the challenges associated with stereocontrol originating from excited state(s). The finite lifetime of an excited state and nearly barrierless subsequent processes present significant challenges in manipulating the stereochemical outcome of a photochemical reaction. Several methodologies were developed to address this bottleneck including photoreactions in confined media and preorganization through noncovalent interactions resulting in stereoenhancement. Yet, stereocontrol in photochemical reactions that happen in solution in the absence of organized assemblies remained largely unaddressed. In an effort to develop a general and reliable methodology, our lab has been exploring non-biaryl atropisomers as an avenue to perform asymmetric phototransformations. Atropisomers are chiral molecules that arise due to the restricted rotation around a single bond (chiral axis) whose energy barrier to rotation is determined by nonbonding interactions (most often by steric hindrance) with appropriate substituents. Thus, atropisomeric substrates are chirally preorganized during the photochemical transformation and translate their chiral information to the expected photoproducts. This strategy, where "axial to point chirality transfer" occurs during the photochemical reaction, is a hybrid of the successful Curran's prochiral auxiliary approach involving atropisomers in thermal reactions and the Havinga's NEER principle (nonequilibrating excited-state rotamers) for photochemical transformations. We have investigated this strategy in order to probe various aspects such as regio-, enantio-, diastereo-, and chemoselectivity in several synthetically useful phototransformations including 6π-photocyclization, 4π-ring closure, Norrish-Yang photoreactions, Paternò-Büchi reaction, and [2 + 2]- and [5 + 2]-photocycloaddition. The investigations detailed in this Account clearly signify the scope of our strategy in accessing chirally enriched products during phototransformations. Simple design modifications such as tailoring the steric handle in atropisomers to hold reactive units resulted in permanently locked/traceless axial chirality in addition to incorporating multiple stereocenters in already complex scaffolds obtained from phototransformation. Further improvements allowed us to employ low energy visible light rather than high energy UV light without compromising the stereoenrichment in the photoproducts. Continued investigations on atropisomeric scaffolds have unraveled new design features, with outcomes that are unique and unprecedented for excited state reactivity. For example, we have established that reactive spin states (singlet or triplet excited state) profoundly influence the stereochemical outcome of an atropselective phototransformation. In general, the photochemistry and photophysics of atropisomeric substrates differ significantly from their achiral counterparts irrespective of having the same chromophore initiating the excited state reactivity. The ability of axially chiral chromophores to impart stereoenrichment in the intramolecular photoreactions appears to be promising. A challenging endeavor for the "axial to point chirality transfer" strategy is to enhance stereoenrichment or alter chemical reactivity in intermolecular photoreactions. Insights gained from our investigations will serve as a platform to venture into more complicated yet fruitful research in terms of broad synthetic utility.

Computational Modeling of Steel Stud Wall Systems for Applications to Blast-Resistant Design

Past research has shown that blast-loaded steel stud walls exhibit a range of different failure mechanisms depending on the stud and track section properties, connection details, and sheathing characteristics. To date, few studies have addressed the computational modeling of these systems. Because large-scale blast tests are expensive and logistically difficult, computational models are needed to evaluate different design options prior to carrying out full-scale experiments. In this paper, the authors present finite-element models that capture the peak load and deformation capacity of steel stud wall systems, accounting for the failure modes observed in past testing. The proposed models strike a balance between level of refinement and computational efficiency. These models were validated against data collected from an extensive laboratory testing program. Based on observations from both the lab tests and computational simulations, recommendations are given for improving the large-deformation response of these systems. Through simple and inexpensive design modifications, the capacity of steel stud walls can be made to far exceed existing response limits.

Stable Precision Grasps by Underactuated Grippers

The ability of underactuated hands to grasp small objects is very limited, because the precision grasp is normally unstable. The goal of this paper is to achieve stable precision grasps by means of simple design modifications of the distal phalanges of the fingers. These modifications comprise the curving of the contact area of the distal phalanx, the application of a mechanical limit to prevent hyperextension of the distal phalanx, and the application of a compliant joint between the proximal and distal phalanges. A model is developed to calculate the limits of the finger dimensions in order to achieve stable precision grasps for different object sizes. An experimental setup is used to test the grasp stability and to verify the calculated results. It is concluded that stable precision grasps exist for the combination of concavely curved distal phalanges with a mechanical limit or with a compliant joint, if the limits to the finger dimensions are satisfied.

Odd Stator Slot Numbers in Brushless DC Machines—An Aid to Cogging Torque Reduction

Brushless permanent-magnet dc machines often use an integral number of slots per pole (e.g., 3 slots/pole) with fully pitched coils in order to obtain a good trapezoidal back-electromotive-force (emf) waveform. However, this can lead to high cogging torque and load torque ripple. A simple solution is to add one additional slot so that the reluctance slotting that causes the ripple is removed, but the winding pattern is closely retained. This paper illustrates that simple design modification, where one additional slot is used so that the machine does not have an integral number of slots per pole. In this paper, the arrangement is analyzed using simple winding analysis and a finite-element analysis which gives more preciseness to calculations. It is found that there is a substantial reduction in cogging and load torque oscillation, thus proving the principle. However, the stator windings are slightly unbalanced and this can lead to vibration. This is also investigated and the resulting unbalanced magnetic pull under load is found to be present but of a low magnitude.

Establishment of sustainable water supply system in small islands through rainwater harvesting (RWH): case study of Guja-do

Many islands in Korea have problems related to water source security and supply. In particular, the water supply condition is worse in small islands which are remote from the mainland. A couple of alternatives are developed and suggested to supply water to islands including water hauling, groundwater extraction, and desalination. However, these alternatives require much energy, cost, and concern in installation and operation. Rainwater harvesting is a sustainable option that supplies water with low energy and cost. However, lack of practical or comprehensive studies on rainwater harvesting systems in these regions hinders the promotion of the system. Therefore, this research examines defects of current RWH systems on an existing island, Guja-do, and provides technical suggestions in quantitative and qualitative aspects. A simple system design modification and expansion of system capacity using empty space such as a wharf structure can satisfy both the qualitative and the quantitative water demand of the island. Since rainwater harvesting is estimated to be a feasible water supply option under the Korean climate, which is an unfavorable condition for rainwater harvesting, implies a high potential applicability of rainwater harvesting technology to other regions over the world suffering from water shortage.

Agricultural supply system traceability, Part I: Role of packing procedures and effects of fruit mixing

Traceability is becoming an integral component of modern agricultural supply chains. Higher-precision traceability and finer granularity of identifiable units of product offer the opportunity to add value to the conventional track and trace information in terms of improved feedback to producers and benefits to supply system efficiency. The packhouse is the major transformer of identifiable units in a horticultural supply system and is the only source of information on these transformations. The major influences on the precision of traceability possible through a packhouse are mixing in the infeed system to the grader, mixing in the packing system and the splitting of fruit stream to different packing outlets. A mixing model has been developed that is able to assign the probabilities of bin origin to individual fruit at the point they are packed into their final packs. In-feed mixing is essentially a mechanical process dependent on both packhouse design and operation. Simple design modification can significantly reduce fruit mixing and improve traceability. Packing lane mixing is a function of both mechanical design and operator factors. Traceability is not a definitive judgement, but a variable and statistical management process with inherent uncertainty. The research suggests there is potential to implement high-precision and fine granularity traceability in the agricultural supply system.

“Underlying” Causes for Settlement of Bridge Approach Pavement Systems

A comprehensive field study of 74 bridges in Iowa was conducted to characterize problems leading to poor performance of bridge approach pavement systems. Subsurface void development caused by water infiltration through unsealed expansion joints, collapse and erosion of the granular backfill, and poor construction practices were found to be the main contributing factors. To characterize the problem, International Roughness Index and profile measurements from several sites were used to show that approach pavement roughness is several times higher than the average roadway condition and are most severe at the abutment-to-approach pavement intersection and transverse expansion joints due to large (5–10cm) joint widths. Further, a settlement time history was documented at one bridge site by measuring the approach slab pavement elevations periodically after completion of bridge construction, revealing a progressive settlement problem under the approach pavement. To better understand the void development under the approach pavement, laboratory compaction tests were performed on granular backfill materials from various bridge sites to quantify their saturated collapse potential in the postconstruction phase. These tests revealed collapse potential of backfill materials in the range of 5–18% (based on volume) with the high values for poorly graded sandy backfill materials, indicating significant settlement problems. Based on the research findings, some relatively simple design and construction modifications are suggested which could be used to alleviate field problems for similar bridge approach pavement systems.