Biocompatible Conjugated Polymer Nanoparticles for Efficient Photothermal Tumor Therapy

Conjugated polymers (CPs) with strong near‐infrared (NIR) absorption and high heat conversion efficiency have emerged as a new generation of photothermal therapy (PTT) agents for cancer therapy. An efficient strategy to design NIR absorbing CPs with good water dispersibility is essential to achieve excellent therapeutic effect. In this work, poly[9,9‐bis(4‐(2‐ethylhexyl)phenyl)fluorene‐alt‐co‐6,7‐bis(4‐(hexyloxy)phenyl)‐4,9‐di(thiophen‐2‐yl)‐thiadiazoloquinoxaline] (PFTTQ) is synthesized through the combination of donor–acceptor moieties by Suzuki polymerization. PFTTQ nanoparticles (NPs) are fabricated through a precipitation approach using 1,2‐distearoyl‐ sn ‐glycero‐3‐phosphoethanolamine‐N‐[methoxy(polyethylene glycol)‐2000] (DSPE‐PEG₂₀₀₀) as the encapsulation matrix. Due to the large NIR absorption coefficient (3.6 L g^‐1 cm^‐1), the temperature of PFTTQ NP suspension (0.5 mg/mL) could be rapidly increased to more than 50 °C upon continuous 808 nm laser irradiation (0.75 W/cm²) for 5 min. The PFTTQ NPs show good biocompatibility to both MDA‐MB‐231 cells and Hela cells at 400 μg/mL of NPs, while upon laser irradiation, effective cancer cell killing is observed at a NP concentration of 50 μg/mL. Moreover, PFTTQ NPs could efficiently ablate tumor in in vivo study using a Hela tumor mouse model. Considering the large amount of NIR absorbing CPs available, the general encapsulation strategy will enable the development of more efficient PTT agents for cancer or tumor therapy.     

Efficient Structure Selection of Polynomial Nonlinear Systems Using Evolutionary Programming

A new method of structure selection or which terms to include into a nonlinear autoregressive moving average with eXogenous inputs (NARMAX) model, based on Evolutionary Programming (EP) has been proposed. The algorithm uses a strategy similar to Elitism where the single best chromosome in a generation is retained and passed to the next. In addition to minimizing the Mean Square Error (MSE), the method introduces an internal term penalty (ITP) function to reject spurious terms under the effects of significant noise. By following an adaptive mutation rate and restricting this to vary within 50%, faster convergence is achieved. To further improve the convergence, a pruning strategy is followed where any insignificant terms are removed from the model by assigning them with a time-to-live parameter. The performance of the proposed method is illustrated considering several examples of nonlinear systems including nonlinear wave force models and has been found to be satisfactory.     

An optimized hardware calibration technique for transmission of real-time applications in VoIP network

Multimedia Tools and Applications - Voice over Internet Protocol (VoIP) uses packet switching to transmit voice, video, data and chat services. VoIP applications depend upon various speech codecs...     

Impact of Temperature Variation on Analog,Hot-Carrier Injection and Linearity Parameters of Nanotube Junctionless Double-Gate-All-Around (NJL-DGAA) MOSFETs

Silicon - Silicon-based Nanotube Junction-less Double-Gate-All-Around (NJL-DGAA) MOSFETs has become a promising solution to high-speed ULSI chip design. However, the change in surrounding...     

A Novel Approach to Investigate the Impact of Hetero-High-K Gate Stack on SiGe Junctionless Gate-All-Around (JL-GAA) MOSFET

Silicon - It is a well-known fact that the gate stacking is used to improve the electrostatic behavior of Si0.5Ge0.5 Junctionless Gate-All-Around (JL-GAA) MOSFETs. In gate stacking, the high-k...     

Processing,tensile, and fracture properties of injection molded Hdpe‐Al2O3‐HAp hybrid composites

The aim of this study is to characterize the physical and mechanical properties of HDPE‐alumina‐HAp composites prepared by injection molding techniques and to demonstrate their superiority over unreinforced HDPE. Composites with up to 30 vol. % of filler, composed of equal volumes of HAp and alumina, were successfully processed by injection molding. On the basis of the analysis of processing results, i.e., melt viscosity, volume flow rate, shear rate, mixing torque, the critical ceramic loading was determined. Tensile tests done at varying crosshead speeds confirm that an increase in ceramic loading results in an increase in strength, as well as a simultaneous decrease in the total elongation at failure. A maximum strength of 20 MPa and a maximum tensile modulus of around 1 GPa was achieved with 30 vol % ceramic loading in semicrystalline HDPE matrix. SEVNB test results demonstrate an improvement in toughness at 20 vol %. The fracture properties are discussed in terms of interfacial bonding between ceramic fillers and the semicrystalline HDPE matrix. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Ground-Free ECG Recording with Two Electrodes

ECG recordings normally use three electrodes?two for the differential inputs of the ECG amplifier and the third for ground. We analyze those situations where the ground electrode can be eliminated. We propose a model for the source of electrical interference and determine various parameter values. Making use of experimentally obtained data for the model parameters we suggest optimal design for a two-electrode amplifier. The two-electrode design is useful for biotelemetry, portable Holter monitors, and portable arrhythmia monitors. Under certain circumstances it may be useful for grounded monitoring equipment. The two-electrode technique has the advantage that it improves patient safety by eliminating the ground electrode. Fewer electrodes make patient attachment easier and lower electrode costs.     

A Battery-Powered Digital Modem for Telephone Transmission of ECG Data

We present the design of a battery-powered digital modem for transmitting ECG signals. It operates from a 5-V battery supply, uses a coil or acoustic coupler for a telephone interface, and consumes only 30 mW during transmission. We show error rates comparable to regular stand-alone modems, well within the acceptable limit of 1 bit per 100 kbits transmitted at a transmission speed of 300 Bd.     

Application of a dynamic programming algorithm for trajectory planning of finger-like manipulators

Dextrous hand designs require planning and coordination of multijointed fingers. This communication presents a dynamic programming algorithm to optimize the trajectory of a finger or a fingerlike manipulator. The algorithm generates a minimum cost trajectory for a specified cost function (such as accuracy or time of travel) and a set of constraints (such as obstacles along the trajectory). We present simulations demonstrating the trajectory planning for simplified fingerlike manipulator configurations. This approach is potentially applicable to several additional situations faced by multijointed fingers employed in dextrous hand designs, such as complex trajectory planning, obstacle avoidance, and fault tolerance. We illustrate some results obtained by computer simulations of these problems.     

Biomimetic Nanocomposites Cloaked with Bioorthogonally Labeled Glioblastoma Cell Membrane for Targeted Multimodal Imaging of Brain Tumors

Brain tumor targeted delivery of diagnostic contrast agents has been an elusive goal due to the presence of the blood brain barrier (BBB) and the complex brain tumor microenvironment. Herein, an ingenious design of nanoscale contrast agents coated by bioorthogonally labeled brain tumor cell membrane for targeted diagnosis of glioblastoma through multiple complementary imaging modalities is presented. Taking advantage of bioorthogonal click reactions, an endothelial integrin receptor‐targeting peptide cRGD is decorated onto the nanocomposite surface to act in synergy with brain tumor cell membrane to offer BBB‐penetrating and homotypic targeting effect in the brain tumor microenvironment. Cellular and animal experimental results validate the superior targeting outcomes achieved by cRGD‐labeled brain tumor cell membrane coating. This study offers an example of a surface modified cell membrane as a potential theranostic strategy to overcome the delivery barriers in brain tumors.