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We report the synthesis of gold nanotwins (Au NTs) on a solid and transparent glass substrate which in turn has been employed for the selective optoplasmonic detection of

To accommodate a variety of users with the growing popularity of 3D printing technology, the concept of usability; the effectiveness of a user’s interaction with the product, must be considered. A seamless user interaction with the currently available commercial 3D printer systems assumes that the users have the required hand strength, ability to stand, and vision, which could be challenging for some learning this new technology. This research intends to utilize the principles of universal design, i.e., the idea of appealing design for all age groups or abilities towards operating the physical 3D printer in order to expand its field of use. Physical challenges of the human body as it moves to interact with desktop fused filament fabrication (FFF) 3D printers were investigated. Following that, a survey was collected, to understand the perspective of 3D printer users in terms of challenges faced while interacting with the machine and troubleshooting them. The survey indicated that users found print bed levelling the most challenging task. As a result, the redesign process for print bed leveling was initiated by the development of design specifications. This paper attempts to shed light on potential improvements that can be made in commercially available desktop systems by implementing universal design guidelines, such that the technology is accessible to a larger population. The process used in this paper is applicable for redesign of any existing product for Universal Design.

Chronic stress is the leading cause of memory impairment today. Various stress-based models are being developed for studying cognitive impairment. Repurposing of existing drugs in a new pharmacology class is the safest and cheapest option for treatment instead of new drug discovery. Vorinostat (VOR) is the first histone deacetylase (HDAC) inhibitor approved for the treatment of cutaneous T-cell lymphoma by the U.S. FDA. VOR follows the rule of five and is reported to cross the blood-brain barrier. Therefore, we aimed to evaluate the procognitive potential of VOR (25 mg/kg) administered by intraperitoneal (ip) route in a stress-based model of chronic corticosterone (CORT) injections (20 mg/kg, subcutaneously (sc)). The study comprised six groups. Normal mice were administered vehicle (VEH) (days 1-21, sc) in the first group, VOR (days 8-21, 25 mg/kg, ip) in the second group, and fluoxetine (FLX) (days 8-21, 15 mg/kg, oral) in the third group. Mice in the remaining three groups were given 20 mg/kg (sc) CORT for 21 days, and VOR (days 8-21, 25 mg/kg, ip) or FLX (days 8-21, 15 mg/kg, oral) was additionally administered to the treatment groups. Behavioral tests such as Morris water maze test, novel object recognition test, and object in place test were performed at the end of the dosing schedule to assess cognition. After behavior tests, mice were sacrificed, and hippocampus was separated from brain tissue for reverse transcriptase polymerase chain reaction (RT-PCR), Western blot, and immunohistochemistry studies. VOR treatment attenuated endoplasmic reticulum (ER) stress in CORT mice as evident from the reduction in DNA damage-inducible transcript 3 (Ddit3) (gene encoding CHOP), caspase 12 (Casp12), and calpain-2 (Capn2) mRNA levels, and cleaved caspase 3 (CASP3) protein expression. Bax inhibitor-1 (BI-1) was significantly increased in VOR-treated CORT mice. VOR also reversed CORT induced increase in HDAC2 level in the CA3 region. The protective effects of VOR were comparable to that of FLX in CORT mice. Thus, VOR has the potential to reverse cognitive dysfunction via modulation of ER stress markers and HDAC2.

Additive manufacturing (AM) offers designers access to the entire volume of an artifact during its build operation, including the embedding of foreign objects, like sensors, motors, and actuators, into the artifact to produce multifunctional products from the build tray. However, the application of embedding requires extensive designer expertise in AM. This research aims to develop a tool to automate design decisions for in situ embedding, eliminating the need for ad hoc design decisions made by experts. Two unique approaches are proposed in this work: shadow projection and voxel simulation. Both of these approaches follow a three-stage methodology to achieve design automation by (1) identifying the optimum orientation for the object, (2) designing cavity, and finally (3) designing the shape converter for a flush surface at the paused layer. The two approaches differ in Stages 2 and 3. Where the shadow projection approach employs a series of point cloud manipulation to geometry of the embedded object, the voxel simulation approach simulates the process of insertion of the embedding geometry into the part voxel by voxel. While both proposed approaches are successful in automating design for embedding complex geometries, they result in tradeoffs between final designs and the time for computation. Computational experiment with six test cases shows that designers must strategically choose from one of the approaches to efficiently automate the digital design for embedding.

Single nucleotide polymorphisms (SNPs) are the most common mutations found in humans and are special molecular signatures providing intricate information pertaining to human migration patterns, ancestral history, and predisposition to diseases. In present modern forensic era, SNPs in the human populations are being used by investigative agencies across the world as productive and sometimes definitive evidence in solving cases especially pertaining to suspect/victim identification or establishing relatedness. In the present book chapter, we have provided a comprehensive account of the use of SNPs in forensic sciences. We have explained the various conventional and most modern cutting edge strategies and approaches of typing SNPs. Most importantly we have detailed the numerous applications of SNP genotyping in DNA forensics including disaster victim identification, suspect identification at the crime scene, and establishing precisely the disputes related to paternity. We have also included a few landmark case-studies which used SNP typing to reach conclusive verdict.

Purpose This paper aims to identify and quantify the effects of additive manufacturing (AM) process interruption on the tensile strength of material extrusion parts, and to find solutions to mitigate it. Design/methodology/approach Statistical analysis was performed to compare the tensile strength of specimens prepared with different process interruption time durations and different embedding methods. Subsequently, specimens were reheated at the paused layer before resuming, and tensile strengths were analyzed to observe any improvements. Findings Process interruption significantly reduced the tensile strength of printed parts by 48 per cent compared to non-interrupted specimens. Reheating the paused layer immediately before resuming the print improved part strength significantly by 47 per cent compared to regular process interrupted specimens and by 90 per cent compared to specimens with embeds. Practical implications The layer-by-layer deposition of material in AM introduces the capability for in situ embedding of functional components into printed parts. This paper shows that tensile properties are degraded during embedding due to the need for process interruption. These effects can be addressed by reheating the paused layer, providing process guidance for embedding with AM. Originality/value This paper provides an understanding of process interruption and embedding effects on mechanical properties of the parts, and how to improve them. The results from this experimental analysis provide crucial information toward design guidelines for multi-functional AM with embedded components.

Poor strength of material extrusion additively manufactured parts has limited the process’s adoption for direct manufacturing of end-use products. These weaknesses are present at material interfaces as a result of material extrusion’s typical deposition. The variety of possible part geometries, along with the multiple toolpath options to deposit material, results in a unique thermal profile that causes varying strength across the part at the material interfaces. Prior research showed that by utilizing polymer weld theory alongside thermal profile information at the layer interfaces, one can predict tensile strength for different designs. However, these thermal profiles are unique at each point of a part’s cross-section, making them challenging to obtain experimentally or analytically. Therefore, this work presents a framework to obtain these interfacial thermal profiles computationally and directly from the programmed material deposition toolpath. A heat transfer simulation technique based on finite difference method is demonstrated and validated experimentally through thermocouple measurements. The practical potential of this simulation is then demonstrated by using the evaluated thermal profile alongside polymer weld theory to estimate the strength of structures with different infill densities and complex internal cavity designs.

Additive manufacturing (AM) offers access to the entire volume of a printed artifact during the build operation. This makes it possible to embedding foreign components (e.g. sensors, motors, actuators) into AM parts, thus enabling multifunctional products directly from the build tray. However, the process of designing for embedding currently requires extensive designer expertise in AM. Current methods rely on a designer to select an orientation for the embedded component and design a cavity such that the component can be successfully embedded without compromising the print quality of the final part. For irregular geometries, additional design knowledge is required to prepare a shape converter: a secondary piece to ensure a flush deposition surface on top of the embedded component. This research aims to develop a tool to automate these different design decisions for in-situ embedding, thus reducing the need for expert design knowledge. A three-stage process is proposed to 1) find the optimum orientation based on cavity volume and cross-section area, 2) create the necessary cavity geometry to successfully insert the component, and 3) perform a Boolean operation to create the digital design for any requisite shape converter. Performance of the tool is demonstrated with four test cases with varying levels of geometric complexity. These test cases show that the proposed process successfully handles arbitrary embedded geometries, though several limitations are noted for future work.

Major depressive disorder (MDD) is a multifactorial neuropsychiatric disorder. Chronic administration of corticosterone (CORT) to rodents is used to mimic the stress associated dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, a well-established feature found in depressive patients. Recently, preclinical studies have demonstrated the antidepressant potential of histone deacetylase (HDAC) inhibitors. So, we examined the antidepressant potential of vorinostat (VOR), a HDAC inhibitor against CORT injections in male mice. VOR (25 mg/kg; intraperitoneal) and fluoxetine (FLX) (15 mg/kg; oral) treatments were provided to CORT administered mice. At the end of dosing schedule, neurobehavioral tests were conducted; followed by mechanistic evaluation through biochemical analysis, RTPCR and western blot in serum and hippocampus. Neurobehavioral tests revealed the development of anxiety/depressive-like behavior in CORT mice as compared to the vehicle control. Depressive-mice showed concomitant HPA axis dysregulation as observed from the significant increase in serum CORT and ACTH. Chronic CORT administration was found to significantly increase hippocampal malondialdehyde (MDA) and iNOS levels while lowering glutathione (GSH) content, as compared to vehicle control. VOR treatment, in a similar manner to the classical antidepressant FLX, significantly ameliorated anxiety/depressive-like behavior along with HPA axis alterations induced by CORT. The antidepressant-like ability of drug treatments against chronic CORT induced stress model, as revealed in our study, may be due to their potential to mitigate inflammatory damage and oxidative stress via modulation of hippocampal NF-κB p65, COX-2, HDAC2 and phosphorylated JNK levels.

This paper proposes implementation of coupled inductor based 7 level inverter with reduced number switches. The inverter which generates the sinusoidal output voltage by the use of coupled inductor with reduced total harmonic distortion. The voltage stress on each switching devices, capacitor balancing and common mode voltage can be minimized. The proposed system which gives better controlled output current and improved output voltage with diminished THD value. The switching devices of the system are controlled by using hysteresis current control algorithm by comparing the carrier signals with constant pulses with enclosed hysteresis band value. The simulation and experimental results of the proposed system outputs are verified using matlab/Simulink and TMS320F3825 dsp controller respectively.

Now the world became more digitalized and the digital communication over the internet increases day by day. At present days the digital data is widely transfer over the internet and the whole information of living being has been uploaded on the server. With the increase of internet use, the misuse of private data also increases. There exist are many hackers and they may easily hack our private data too. So now a days security of private data has become major part of concern. For the prospective of security, cryptography and steganography of secret data can be used. In cryptography the original secret message is converted into ciphertext that is understood. While in steganography technique the secret data is hiding in cover media. Cover media may be multimedia file such as data, images, audios and videos. In this paper we are introducing video steganography technique using discrete wavelet packet transform (DWPT). Additional security can be achieved by using combined cryptography and steganography for better security of secret information. Result shows that the video steganography using discrete wavelet transform provide better performance parameter as compare to other technique of steganography.