Dual Response Research Articles

Engineering Self-Adaptive Multi-Response Thermochromic Hydrogel for Energy-Saving Smart Windows and Wearable Temperature-Sensing.

Buildings account for ≈40% of the total energy consumption. In addition, it is challenging to control the indoor temperature in extreme weather. Therefore, energy-saving smart windows with light regulation have gained increasing attention. However, most emerging base materials for smart windows have disadvantages, including low transparency at low temperatures, ultra-high phase transition temperature, and scarce applications. Herein, a self-adaptive multi-response thermochromic hydrogel (PHC-Gel) with dual temperature and pH response is engineered through "one-pot" integration tactics. The PHC-Gel exhibits excellent mechanical, adhesion, and electrical conductivity properties. Notably, the low critical solubility temperature (LCST) of PHC-Gel can be regulated over a wide temperature range (20-35°C). The outdoor practical testing reveals that PHC-Gel has excellent light transmittance at low temperatures and radiation cooling performances at high temperatures, indicating that PHC-Gel can be used for developing energy-saving windows. Actually, PHC-Gel-based thermochromic windows show remarkable visible light transparency (Tlum ≈95.2%) and solar modulation (△Tsol ≈57.2%). Interestingly, PHC-Gel has superior electrical conductivity, suggesting that PHC-Gel can be utilized to fabricate wearable signal-response and temperature sensors. In summary, PHC-Gel has broad application prospects in energy-saving smart windows, smart wearable sensors, temperature monitors, infant temperature detection, and thermal management.

Research on dual lateral log simulation of shale bedding fractures under different influencing conditions

Micro scale fractures play a crucial role in facilitating the migration of oil and gas in low permeability shale reservoirs. However, the identification of such fractures is a complex task. The efficacy of the dual lateral log physical field changes as a means of identifying shale micro fractures remains uncertain. To address this issue, a three-layer shale bedding fracture model was developed using the finite element method and core and conventional logging data from eight wells, which was based on different shale reservoirs within the Yanchang Formation in the Ordos Basin. The present study examines the dual lateral log response characteristics resulting from distinct characteristics of horizontal bedding fractures, with a focus on the response mechanism. The simulation of logging response characteristics of shale and siltstone combination were utilized by core statistical data for verification purposes. The results indicate that under the lithology combination of shale and siltstone, the magnitude of the difference between the resistivity of the filled fracture and the formation resistivity, the greater the formation resistivity of the shale itself, the wider the fracture width, and the greater the difference between the apparent resistivity and the real formation resistivity. Furthermore, the suitable conditions for the detection of shale bedding fracture characteristics by dual lateral log are clarified. In the presence of effective filling, the dual lateral log has the capability to identify shale fractures at the micron scale. The findings of our study establish a theoretical framework for the identification and assessment of shale fractures, and furnish technical assistance for the optimal selection of “sweet spots” within shale reservoirs and the precise evaluation of reservoirs. This study lays a theoretical foundation for the identification and evaluation of shale fractures, and provides technical support for the optimal “sweet spot” selection of shale reservoirs and the accurate evaluation of reservoirs.

Bio-inspired dual-responsive photonic crystal with smart responsive hydrogel for pH and temperature detection

Responsive photonic crystals (PCs) with bio-inspired microstructures and tailorable functionalities are of critical importance for their potential applications in diverse fields such as biological detection, sensing, decoration, anti-counterfeiting, etc. However, limited by preparation technologies and design theories, it is still a challenge to accurately and uniformly deposit smart responsive materials on natural PC structures and achieve dual stimulus response. Herein, a simple and rapid in situ polymerization method is presented for preparing dual-responsive PCs with ultra-precise micro-/nanoscale hierarchical structures. Exposure of the reaction site by deacetylation of Morpho butterfly wings allows in situ polymerisation of poly (N-isopropylacrylamide-co-acrylic acid) (P(NIPAAM-co-AAc)) on the surface of the natural photonic structure. The obtained P(NIPAAM-co-AAc) photonic crystals (P(NIPAAM-co-AAc)-PCs) exhibited a dual response to pH and temperature reversibility. In addition, the synergistic effect of the structures and materials on the optical response of the natural PCs is revealed. This work allows the combination of natural hierarchical PC structures with smart hydrogel to achieve an optical response to pH and temperature, thus opening up the channels for responsive PC to multiple stimulus responses.

Field-driven design and performance evaluation of dual functionally graded triply periodic minimal surface structures for additive manufacturing

Triply periodic minimal surface (TPMS) structures prepared by additive manufacturing (AM) have been widely used in aerospace and thermal management systems due to their functional advantages such as high specific strength and excellent heat transfer coefficient. However, lattices with uniform or simple gradients cannot match the regional diversity needs of functional advantages in service. This study proposed a field-driven AM data processing framework for dual functionally graded TPMS lattices. For unified data processing, mathematical functions, simulated outcomes, and geometric models were transformed into fields. I-WP and Diamond units were selected as the primitive and filling structures of Ti-6Al-4V lattices, respectively. According to the functional requirements, the gradient distribution design guided by the simulated stress field is completed through the proposed framework. The results illustrate that the field-driven dual graded lattices present superior compressive mechanical response. At almost equal volume fractions, their compressive strength is approximately 100% more than that of primitive lattices and 69% greater than that of dual uniform lattices. Furthermore, the dual lattices have larger specific surface areas than the primitive lattices, making them better at heat insulation and heat dissipation. This field-driven digital framework will show enormous potential in the matching design of functionally graded lattices.

Adenovirus-assembled DC vaccine induces dual-targeting CTLs for tumor antigen and adenovirus to eradicate tumors

The dendritic cell (DC) vaccine is a promising cancerimmunotherapy strategy, but its efficacy in treating the solid tumor is limited. To overcome this limitation, an oncolytic adenovirus (OAV-IL-12) was developed to enhance antigen targeting ability of adenovirus-assembled DC vaccine (DCs-CD137L/CAIX) for renal carcinoma treatment. Peritumoral administration of OAV-IL-12 increased the number of tumor-infiltrating DCs and their subsets (CD8+DCs and CD103+DCs). Combining OAV-IL-12 with DCs-CD137L/CAIX significantly inhibited the growth of subcutaneous tumors by inducing potent cytotoxic T lymphocyte (CTL) effect and improving the immune infiltration in tumor lesions. Interestingly, this treatment also reduced tumor growth distal to the OAV-IL-12 injecting side via eliciting a systemic CTL response. Furthermore, OAV-IL-12 potentiated DCs-CD137L/CAIX treatment induced dual CTL responses against both CAIX and adenovirus antigens. The therapeutic benefits of this treatment approach mainly relied on multifunctional CD8+T cell immune responses, as indicated by the depletion assay. Moreover, OAV-IL-12 potentiated DCs-CD137L/CAIX treatment generated a long-lasting protective effect against tumors by inducing memory CD8+T cell immune responses. These results suggest that the effective tumor targeting of the adenovirus-based DC vaccine, boosted by OAV-IL-12, is a promising treatment approach for renal carcinoma and other solid tumors.

Dual Responses of Fluorescence and Circular Dichroism for Antibiotics by a Cationic Cage in Water

AbstractA tetraphenylethene (TPE)-based cationic cage (1) can form a 1:2 host–guest complex with antibiotics in water and imparts dual responses of fluorescence and circular dichroism (CD) to antibiotics based on the fluorescence and adaptive chiral conformation of the TPE units. Moreover, the host–guest complexes 1⊃(antibiotic)2 exhibited good antibacterial activity.

Topological Regulating Bismuth Nano-Semiconductor for Immunogenic Cell Death-Mediated Sonocatalytic Hyperthermia Therapy.

Immunogenic cell death (ICD) can activate the body's immune system via dead cell antigens to achieve immunotherapy. Currently, small molecule drugs have been used for ICD treatment in clinical, however, how to precisely control the induced ICD while treating tumors is of great significance for improving therapeutic efficacy. Based on this, a sono/light dual response strategy to tumor therapy and activation of ICD is proposed. A topological synthesis method is used to obtain sulfur-doped bismuth oxide Bi2 O3-x Sx (BS) using BiF3 (BF) as a template through reduction and a morphology-controllable bismuth-based nano-semiconductor with a narrow bandgap is constructed. Under the stimulation of ultrasound, BS can produce reactive oxygen species (ROS) through the sonocatalytic process, which cooperates with BS to consume glutathione and enhance cellular oxidative damage, further inducing ICD. Due to the introduction of sulfur in the reduction reaction, BS can achieve photothermal conversion under light, and combine with ROS to treat tumors. Further, with the assistance of ivermectin (IVM) to form composite (BSM), combined with sono/light dual strategy, ICD is promoted and DCs maturation is accelerated. The proposed ICD-mediated hyperthermia/sonocatalytic therapy strategy will pay the way for synergetic enhancement of tumor treatment efficacy and provide a feasible idea for controllable induction of ICD.

Ultrawideband Dual Circularly Polarized Waveguide Array Antenna for K- and Ka-Bands Satellite Communications

In the letter, a wideband dual circularly polarized (CP) waveguide antenna array is designed for K and Ka dual-band satellite communications. A multi-stage square waveguide structure is exploited into the radiating part to facilitate the excitation of a dual polarization response. A ridge waveguide polarizer is integrated to form the left-hand circular polarization (LHCP) and the right-hand circular polarization (RHCP). For a better arrangement of the feeding network, a transition structure with E-plane waveguides to double-ridge waveguides reduces the cross-sectional area of the feeding network. An 8 x 8 array antenna prototype was designed, fabricated and measured for demonstration purposes. The axial ratio (AR) and impedance bandwidth of the array antenna are more than 45%, according to simulation and measurement results. Input reflection coefficient and isolation lower than -15 dB for the dual CP from 19 to 30 GHz, the total antenna efficiency for the entire operating band exceeded 72%. For both polarizations, the peak gain ranges between 24.6 and 28.8 dBi from 19 to 30 GHz.

Convex Programming-Based Robust Optimization Procedure for Blast-Excited Structures with Bounded Uncertainty

Application of the robust optimization (RO) technique to ensure the least possible deviation of structural performance is gaining increasing attention in recent years. However, most RO studies have been conducted in the probabilistic domain, where sufficient uncertainty information is available to construct probability distribution functions of response parameters. But, in many cases, such as for structures under underground blast excitation, hazard parameters like charge weight and charge center distance do not have any definite probability density function. Only their ranges of variations are known to an engineer. Hence, it is more logical to model these parameters as uncertain-but-bounded (UBB) type, which requires only bounds of variations to characterize the uncertainty. The available RO studies in the UBB-domain mainly deal with static loads. Studies on time-variant dynamic loads, such as blast load, are scarce in the existing literature. Also, blast load time-histories show record-to-record variations in their signatures, even with the same setup of hazard parameters. This aspect cannot be considered by the conventional convex programming approaches of RO in the UBB domain. To address all these issues, a new RO procedure is proposed in the present study, which is based on the dual response surface method. The proposed RO procedure can transform the complex simulation-based RO procedure under dynamic blast load to an equivalent deterministic problem with explicit constraints. Thereby, the RO can be easily solved by a gradient-based optimizer. The effectiveness of the proposed approach is elucidated by the complex real-world problems of a multistory building and an underground reinforced concrete bunker. The results are compared with conventional RO approaches. The results show that the proposed approach consistently yields more economic as well as robust solutions in a computationally efficient way.

Space Station-like Composite Nanoparticles for Co-Delivery of Multiple Natural Compounds from Chinese Medicine and Hydrogen in Combating Sensorineural Hearing Loss.

Ototoxic drugs such as aminoglycoside antibiotics and cisplatin (CDDP) can cause sensorineural hearing loss (SNHL), which is closely related to oxidative stress and the acidification of the inner ear microenvironment. Effective treatment of SNHL often requires multifaceted approach due to the complex pathology, and drug combination therapy is expected to be at the forefront of modern hearing loss treatment. Here, space-station-like composite nanoparticles (CCC@mPP NPs) with pH/oxidation dual responsiveness and multidrug simultaneous delivery capability were constructed and then loaded with various drugs including panax notoginseng saponins (PNS), tanshinone IIA (TSIIA), and ammonia borane (AB) to provide robust protection against SNHL. Molecular dynamics simulation revealed that carboxymethyl chitosan/calcium carbonate-chitosan (CCC) NPs and monomethoxy poly(ethylene glycol)-PLGA (mPP) NPs can rendezvous and dock primarily by hydrogen bonding, and electrostatic forces may be involved. Moreover, CCC@mPP NPs crossed the round window membrane (RWM) and entered the inner ear through endocytosis and paracellular pathway. The docking state was basically maintained during this process, which created favorable conditions for multidrug delivery. This nanosystem was highly sensitive to pH and reactive oxygen species (ROS) changes, as evidenced by the restricted release of payload at alkaline condition (pH 7.4) without ROS, while significantly promoting the release in acidic condition (pH 5.0 and 6.0) with ROS. TSIIA/PNS/AB-loaded CCC@mPP NPs almost completely preserved the hair cells and remained the hearing threshold shift within normal limits in aminoglycoside- or CDDP-treated guinea pigs. Further experiments demonstrated that the protective mechanisms of TSIIA/PNS/AB-loaded CCC@mPP NPs involved direct and indirect scavenging of excessive ROS, and reduced release of pro-inflammatory cytokines. Both in vitro and in vivo experiments showed the high biocompatibility of the composite NPs, even after long-term administration. Collectively, this work suggests that composite NPs is an ideal multi-drug-delivery vehicle and open new avenues for inner ear disease therapies.

Exploring valley polarized transport in graphene bilayer flakes

Valleytronics offers new routes to explore possible dual electronic responses related to the valley origin of the carriers. Graphene is known as an optimal material for devices based on valley-filter transport due to the double Dirac cones. Here we focus on understanding the role played by geometrical spatial details in the valley-dependent transport of bilayered graphene flakes, with long length, simulating nanoribbons. Flakes of different widths are considered at the stacking region. We also explore changing the valley transmission when a bias potential is applied. A tight-binding Hamiltonian is used to model the system, and the conductance is obtained by Landauer-Büttiker’s formalism and recursive Green’s function method. Our findings show that considering different bilayered graphene flake widths produces valley-polarized transmissions due to the presence of edge states. Furthermore, the corresponding energy range for which the valley filter occurs depends on the width asymmetries details. The theoretical analysis presented here indicates a potential route for valley-filter transmission scenarios of relatively easy engineering implementation.

The Dirichlet Dual Response Model: An Item Response Model for Continuous Bounded Interval Responses

Standard response formats such as rating or visual analogue scales require respondents to condense distributions of latent states or behaviors into a single value. Whereas this is suitable to measure central tendency, it neglects the variance of distributions. As a remedy, variability may be measured using interval-response formats, more specifically the dual-range slider (RS2). Given the lack of an appropriate item response model for the RS2, we develop the Dirichlet dual response model (DDRM), an extension of the beta response model (BRM; Noel & Dauvier in Appl Psychol Meas, 31:47–73, 2007). We evaluate the DDRM’s performance by assessing parameter recovery in a simulation study. Results indicate overall good parameter recovery, although parameters concerning interval width (which reflect variability in behavior or states) perform worse than parameters concerning central tendency. We also test the model empirically by jointly fitting the BRM and the DDRM to single-range slider (RS1) and RS2 responses for two Extraversion scales. While the DDRM has an acceptable fit, it shows some misfit regarding the RS2 interval widths. Nonetheless, the model indicates substantial differences between respondents concerning variability in behavior. High correlations between person parameters of the BRM and DDRM suggest convergent validity between the RS1 and the RS2 interval location. Both the simulation and the empirical study demonstrate that the latent parameter space of the DDRM addresses an important issue of the RS2 response format, namely, the scale-inherent interdependence of interval location and interval width (i.e., intervals at the boundaries are necessarily smaller).

Study on the actuation mechanism of liquid metal thermosensitive hydrogel soft robot

PNIPAm thermosensitive hydrogel (TSH) has attracted a lot of attention from academic scholars due to its smart volumetric phase transition response to external weak stimuli. However, it cannot simultaneously balance and optimize its tensile properties and response speed. Then, we developed LM-TSH with liquid metal (LM) as an additive, and its elongation at break can reach 768%. In this work, LM-TSH and magnetic TSH are combined to develop a double-layer TSH actuator with multi-field response behavior, which realizes the dual actuation response to near-infrared (NIR) light and high-frequency alternating magnetic field. In addition, a TSH soft robot with two-layer structure is designed, which can realize multi-gait behaviors such as jumping, transporting cargos, and crossing the height obstacle in multiple environments.

Magnetic WS2 nanosheets functionalized by biomimetic lipids with enhanced dispersibility for combined photothermal and chemotherapy therapy

In recent years, multi-target combination therapy has received extensive attention as a method to improve the effectiveness of tumor treatment. In this study, the tungsten disulfide nanosheets (WS2) were firstly modified with iron oxide nanoparticles (IONPs), and then the surface was modified with lipids, to construct a lipid-modified magnetic WS2 composite nanomaterial system (mWS2-lipid). The nanocomposites exhibited high doxorubicin (DOX)-loading amount (179.53 ± 3.24%) and excellent photothermal property, which can reach 60.7 °C in 10 min under near-infrared (NIR) light irradiation of 808 nm, 2 W/cm2. After lipid modification, the dispersity and stability of nanoparticles in water, phosphate buffered saline (PBS) and cell culture medium were greatly improved. The attached DOX exhibits an obvious dual response of pH and NIR. Cell experiment results show that mWS2-lipid has no obvious cytotoxicity, as for the cytotoxicity of DOX-loaded material as well as photothermal ablation, it was concentration-dependent. Finally, in vivo photothermal experiments confirmed that the modification of the material by lipids increased its accumulation level in tumors. MWS2-lipid is therefore a good choice for cancer therapy combining photothermal treatment with chemotherapy.

Integrated multifunctional molecular logic device powered by ion-specific dual mode optical responses

The current letter presents a new model of creating flexible interconvertible logic circuits by using various chemical components as inputs out of a specifically designed molecule. Very distinct output optical signals were received when Hg2+ and F− ions were incorporated as specific inputs. Interestingly, the degrees of responses, as quantified by spectral changes, were altered in the presence of specific masking agents or water. Thus, to obtain the intended results, multiple concentration modulated reversible and irreversible spectroscopic experiments were designed in a case-specific manner to examine the changes in absorption spectra at multiple channels. Beyond conventional logic gates like NOR, OR, AND, and NAND, we were also competent to create several integrated logic circuits including IMPLICATION, INHIBIT, TRANSFER, and NOT-TRANSFER. It's amazing how simple it is to switch the sort of logic sense in this case thanks to optical toggling.

Preparation of Fe3O4/SiO2@CDS@Pt Micromotors for Dual‐Mode Detection of Blood Lead

AbstractIt is necessary to accurately detect the content of lead in blood. Here, we investigate the preparation of magnetic mesoporous silica tubular (MMST) micromotors and their application in blood lead detection. Specifically, a magnetic MMST/Carbon dots (CDs)/Pt tubular micromotor with fluorescence property and autonomous motion ability was prepared. Results show that the micromotor has a dual response of fluorescence and speed to trace lead ions in blood. In the blood lead concentration range (0.001 ng/mL–31.62 ng/mL), the fluorescence intensity and movement speed of the micromotor have a linear relationship with the blood lead concentration, respectively. This dual‐detection platform provides a new idea for the detection of blood lead. It is the first time to combine the quantum dots and the motion rate of motor to detect lead ions in blood. It may have some potential value in the field of biosensors in the future.

Biomimetic patternable polyhydroxyl nanocellulose/MXene films sequentially bridged through a synergistic hydrogen and ionic interaction with tunable multi-photoresponsive performances

High-performance electronics based on transition-metal carbides/nitrides (MXene) have attracted extensive attention due to their two-dimensional structure, modifiable surface chemistry and excellent conductivity. However, because of the weak interconnections between adjacent nanosheets, the construction of robust and flexible macroscopic MXene-based films for wearable electronics remains a challenge. Herein, mechanically tough, highly electroconductive and multi-photoresponsive films (TTM-Al) with a hierarchical nacre-like structure composed of tannic acid-modified 2,2,6,6-tetramethylpiperidin-1-yloxy-oxidized cellulose nanofibers (TA@TOCNs) and MXene are developed via sequentially bridged hydrogen and ionic bonds. TA@TOCNs with abundant phenolic hydroxyl groups as the intercalation layer can enhance the hydrogen bonding interactions with adjacent MXene nanosheets and improve the dispersibility, film-forming ability, mechanical toughness, as well as the in-plane orientation of MXene nanosheets, which can facilitate the construction of well-aligned “brick and mortar” structure. The ionic bonds induced by aluminum ions and oxygen-containing groups in TA@TOCNs and MXene can not only strengthen the interlocking ability and mechanical toughness of TTM-Al, but also promote the electron transfer and heat conduction between MXene nanosheets. Benefiting from the synergism of sequentially bridged hydrogen and ionic bonds, the optimized ultra-thin TTM-Al (∼40 μm) integrates high mechanical strength (∼118.56 MPa), toughness (∼6.84 MJ m−3), electroconductivity (∼5587 S m−1), photoelectric response (photosensitivity ∼ 3050%) and fast photothermal conversion capability (saturation temperature up to 181.6 °C in only 20 s) under near-infrared irradiation. The patternable and flexible devices based on polydimethylsiloxane encapsulated TTM-Al demonstrate the tunable photoelectric/photothermal dual response, enhanced mechanical and waterproof properties, delivering an alternative construction strategy for next-generation multifunctional photoresponsive wearable devices.

Preparation of pH/Light dual-responsive biocompatible polymer micelles: Application to curcumin delivery

Polymer micelles play an important role in the research of drug delivery system because of their nano-size, unique “core-shell” structure and surface modifiability. A pH/photosensitive drug carrier, PEG-PDMAEMA-PNBAE, was synthesized by atom transfer radical polymerization (ATRP) using hydrophilic poly (N, N dimethylaminoethyl methacrylate) (PDMAEMA) as the pH-responsive chain segment and hydrophobic poly (o-nitrobenzyl acrylate) (PNBAE) as the light-responsive chain segment. The molecular and structural characteristics of the polymer were spectroscopically characterized with Fourier transform infrared spectrometer (FT-IR), Nuclear magnetic resonance hydrogen spectrum (1H NMR) and Gel permeation chromatography column (GPC). The morphology and size of micelles were observed by Scanning electron microscope (SEM) and Transmission electron microscope (TEM). The stability of micelles was detected by Laser particle size analyzer (DLS). The Critical micelle concentration (CMC) of the polymer was analyzed by Fluorescence spectrophotometer (Flu), and the photosensitivity of the micelles was determined by Ultraviolet–visible spectrophotometer (UV). The results showed that the synthesized polymers could self-assemble into homogeneous and stable spherical micelles and their particle size was about 100 nm with effective light sensitivity. Curcumin (Cur) was used as a model drug to investigate the adsorption and release abilities of the micelles. The adsorption performance test of the polymeric micelles showed an encapsulation rate of 77.82% and a drug loading capacity of 13.46%. In vitro drug release results showed cumulative drug release rates of 31.79% and 46.55% at pH 5.5 and pH 5.5+UV, indicating the dual pH and light responsiveness of the synthesized carrier. The in vitro hemolysis and cytotoxicity test demonstrated that the carrier has good biosafety.

Response uncertainty influences response bias in the sustained attention to response task: a signal detection theory perspective.

In the current investigation, we modified the high Go, low No-Go Sustained Attention to Response Task (SART) by replacing the single response on Go trials with a dual response to increase response uncertainty. In three experiments, a total of 80 participants completed either the original SART with no response uncertainty regarding the Go stimuli, or versions of the dual response SART in which response probabilities for the two possible responses to the Go stimuli varied from 0.9-0.1, 0.7-0.3, to 0.5-0.5. This resulted in a scale of increasing response uncertainty based on information theory to the Go stimuli. The probability of No-Go withhold stimuli was kept.11 in all experiments. Using the Signal Detection Theory perspective proposed by Bedi et al. (Psychological Research: 1-10, 2022), we predicted that increasing response uncertainty would result in a conservative response bias shift, noted by decreased errors of commission and slower response times to both Go and No-Go stimuli. These predictions were verified. The errors of commission in the SART may not be a measures of conscious awareness per se, but instead indicative of the level of participant trigger happiness-the willingness to respond quickly.

Dual-Band and Wideband Bandpass Filters Using Coupled Lines and Tri-Stepped Impedance Stubs.

In this paper, two bandpass filters-one with a dual-band response and the other with a wideband response-were designed, implemented, and experimented with. The filters are based on the novel combination of series coupled lines and tri-stepped impedance stubs. However, coupled lines along with tri-stepped impedance open stubs (TSIOSs) give a third-order dual passband response. The advantage of dual-band filters using coupled lines and TSIOSs is that they have wide passbands that are close together and separated by a single transmission zero. In contrast, the inclusion of tri-stepped impedance short-circuited stubs (TSISSs) instead of TSIOSs provides a fifth-order wide passband response. The advantage of wideband bandpass filters using coupled lines and TSISSs is that they have a very good selectivity factor. Theoretical analysis was carried out to validate both filter configurations. The tested bandpass filter using coupled lines and TSIOS units had two close wide passbands operating at 0.92 and 1.52 GHz center frequencies, respectively. The dual-band bandpass filter was implemented to operate in GSM and GPS applications. The first passband had a 3 dB fractional bandwidth (FBW) of 38.04%, while the second passband had a 3 dB FBW of 22.36%. The experimental result of the wideband bandpass filter (with coupled lines and TSISS units) had a center frequency of 1.51 GHz with a 3 dB fractional bandwidth of 62.91% and a selectivity factor of 0.90. A good congruence was demonstrated between the full-wave simulated and tested results for both filters.