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A switchable bandstop filter is proposed herein. In order to achieve switchability between a single ultra‐wide stopband and dual wide stopbands, a complex process of coupling synthesis is not necessarily required. By setting two diodes at the input and output port separately, this bandstop filter can be switched between single and dual stopbands. An exemplary bandstop filter with central frequency at 2 GHz is fabricated on Rogers RO4003C, a substrate with a thickness of 0.813 mm and an area occupying 29.3 × 29.7 mm. Agreement between the theoretical and measured results can validate the proposed circuit.

Full-spectrum flow cytometry is now routinely used in many laboratories internationally, and the demand for this technology is rapidly increasing. With capacity to use larger and more complex staining panels, standardized protocols are required for optimal panel design and analysis. Importantly, for ex vivo analysis, tissue preparation methods also need to be optimized to ensure samples are truly representative of tissues in situ. This is particularly relevant given the recent interest in adaptive immune cells that form residency in specific organs. Here we provide optimized protocols for tissue processing and phenotyping of memory T cells and natural killer T (NKT) cell subsets from liver, lung, spleen, and lymph node using full-spectrum flow cytometry. We provide a 21-color antibody panel for identification of different memory subsets, including tissue-resident memory T (T

A novel structure of the multi-passband bandpass filters has been proposed in this article. Multi-sectional short-circuit transmission lines shunted with transmission lines are utilized. By properly choosing the proposed structure's electrical lengths and impedances, multiple passbands can be easily controlled. In addition, the design procedures have been described in detail, and 3D architectures are provided. Because of the parasitic effect among capacitors for a physical 3D circuit, there is some slight difference between the theoretical predictions and measured results. However, generally speaking, the measured results match well with the theoretical predictions. Therefore with high integration and compact size, the proposed multi-passband filter is suitable for implementation in a multi-chip module. By the way, because insertion loss measurement is related to the degree and bandwidth of a filter, the performance of a filter with resonators can be well indicated by translating the measurement into an unloaded Q of a resonator.

A novel planar bandstop filter with high insertion loss is proposed. With the assistance of coupled lines with open stubs at the input and output ports, the newly proposed structure is different from the conventional bandstop filter. With the coupled lines mentioned above, selectivity and stopband rejection of the newly proposed planar bandstop filter can be effectively enhanced. Moreover, the attenuation level of the proposed structure can be controlled by adjusting the resonant frequency of each resonator. Design equations can be obtained with the assistance of the lossless transmission line model and parallel coupled-line model. In order to validate the analysis, a bandstop filter, with a fractional bandwidth of 14% for the measured stopband at 50 dB, is fabricated.

In this study, a switchable bandstop filter is proposed. In order to achieve the switchability between a single ultra-wide stopband and dual wide stopbands, the complex process of coupling synthesis is not required. By setting two diodes at the input and output port separately, this bandstop filter can be switched between single and dual stopbands. An exemplary bandstop filter with the central frequency at 2 GHz is fabricated on Rogers RO4003C, the substrate with thickness of 0.813 mm and with an area occupying 29.3 mm × 29.7 mm. The agreement between theoretical and measured results can validate our proposed circuit.

Aim: The efficacy of anti-lymphoma vaccines that exploit the cellular adjuvant properties of activated natural killer T (NKT) cells were examined in mouse models of CNS lymphoma. Materials & methods: Vaccines were prepared by either loading the NKT cell agonist, α-galactosylceramide onto irradiated and heat-shocked B- and T-lymphoma cells, or chemically conjugating α-galactosylceramide to MHC-binding peptides from a lymphoma-associated antigen. Vaccine efficacy was analyzed in mice bearing intracranial tumors. Results: Both forms of vaccine proved to be effective in preventing lymphoma engraftment through activity of T cells that accessed the CNS. Established lymphoma was harder to treat with responses constrained by Tregs, but this could be overcome by depleting Tregs prior to vaccination. Conclusion: Simply designed NKT cell-activating vaccines enhance T-cell responses and have the potential to protect against CNS lymphoma development or prevent CNS relapse. To be effective against established CNS lymphoma, vaccines need to be combined with Treg suppression.

A compact microstrip bandstop filter is proposed with wider stopband and larger insertion loss. By adopting coupled lines added with open stubs connected at the input and output port of the bandstop filter, the selectivity and stopband rejection can be increased significantly. Moreover, the attenuation level can be controlled by choosing the resonant frequencies of four resonators. This bandstop filter is fabricated with 14.75% fractional bandwidth for measuring at the stopband of 50 dB.

A planar bidirectional absorptive bandstop filter with a wide absorptive bandwidth and compact circuit size is proposed. The proposed absorptive bandstop filter is developed from the absorptive coupled line. Moreover, by adopting the symmetrical structure, both the input and output ports can be used to absorb the injected power. Furthermore, to broaden the stopband bandwidth, the π-shaped transmission lines are included. In addition, design equations are provided for synthesizing the proposed absorptive bandstop filter. In order to validate the analysis, a wide-absorptive bandstop filter has been fabricated, with 20 dB for the absorption and 18.7% for the fractional bandwidth.

The development of a universal vaccine for influenza A virus (IAV) that does not require seasonal modification is a long-standing health goal, particularly in the context of the increasing threat of new global pandemics. Vaccines that specifically induce T cell responses are of considerable interest because they can target viral proteins that are more likely to be shared between different virus strains and subtypes and hence provide effective cross-reactive IAV immunity. From a practical perspective, such vaccines should induce T cell responses with long-lasting memory, while also being simple to manufacture and cost-effective. Here we describe the synthesis and evaluation of a vaccine platform based on solid phase peptide synthesis and bio-orthogonal conjugation methodologies. The chemical approach involves covalently attaching synthetic long peptides from a virus-associated protein to a powerful adjuvant molecule, α-galactosylceramide (α-GalCer). Strain-promoted azide-alkyne cycloaddition is used as a simple and efficient method for conjugation, and pseudoproline methodology is used to increase the efficiency of the peptide synthesis. α-GalCer is a glycolipid that stimulates NKT cells, a population of lymphoid-resident immune cells that can provide potent stimulatory signals to antigen-presenting cells engaged in driving proliferation and differentiation of peptide-specific T cells. When used in mice, the vaccine induced T cell responses that provided effective prophylactic protection against IAV infection, with the speed of viral clearance greater than that seen from previous viral exposure. These findings are significant because the vaccines are highly defined, quick to synthesize, and easily characterized and are therefore appropriate for large scale affordable manufacture.

An important goal of vaccination against viruses and virus-driven cancers is to elicit cytotoxic CD8+ T cells specific for virus-derived peptides. CD8+ T cell responses can be enhanced by engaging help from natural killer T (NKT) cells. We have produced synthetic vaccines that induce strong peptide-specific CD8+ T cell responses in vivo by incorporating an NKT cell-activating glycolipid. Here we examine the effect of a glycolipid-peptide conjugate vaccine incorporating an NKT cell-activating glycolipid linked to an MHC class I-restricted peptide from a viral antigen in human peripheral blood mononuclear cells. The vaccine induces CD1d-dependent activation of human NKT cells following enzymatic cleavage, activates human dendritic cells in an NKT-cell dependent manner, and generates a pool of activated antigen-specific CD8+ T cells with cytotoxic potential. Compared to unconjugated peptide, the vaccine upregulates expression of genes encoding interferon-γ, CD137 and granzyme B. A similar vaccine incorporating a peptide from the clinically-relevant human papilloma virus (HPV) 16 E7 oncoprotein induces cytotoxicity against peptide-expressing targets in vivo, and elicits a better antitumor response in a model of E7-expressing lung cancer than its unconjugated components. Glycolipid-peptide conjugate vaccines may prove useful for the prevention or treatment of viral infections and tumors that express viral antigens.

The planar power divider with a wide passband/ stopband and filtering characteristics is proposed in this letter. In order to increase the slope rate around the passband skirt, the modified parallel-coupled bandpass filter is adopted. Moreover, utilizing the stub-loaded resonator within the filter, a wide passband can be achieved. Furthermore, the stopband bandwidth and attenuation can be extended with the stepped-impedance coupled lines. An exemplary design of the filtering power divider operated at 2 GHz is presented. In addition, the measured fractional bandwidth at 3 dB and attenuation in the stopband are 57.1% and 40 dB, respectively.

A compact planar crossover with four intersecting channels is proposed. By using two cascoded rings, the crossover with eight ports is constructed. The derived electrical lengths and selected impedance ratio between the interconnected lines and the outer ring are also used to achieve the desired central frequency. The measured and theoretically calculated results match well so that the feasibility of the proposed circuit is validated.

Activated NKT cells can stimulate antigen-presenting cells leading to enhanced peptide antigen-specific immunity. However, administration of potent NKT cell agonists like α-galactosylceramide (α-GalCer) can be associated with release of high levels of cytokines, and in some situations, hepatotoxicity. Here we show that it is possible to provoke sufficient NKT cell activity to stimulate strong antigen-specific T cell responses without these unwanted effects. This was achieved by chemically conjugating antigenic peptides to α-galactosylphytosphingosine (α-GalPhs), an NKT cell agonist with very weak activity based on structural characterisation and biological assays. Conjugation improved delivery to antigen-presenting cells in vivo, while use of a cathepsin-sensitive linker to release the α-GalPhs and peptide within the same cell promoted strong T cell activation and therapeutic anti-tumour responses in mice. The conjugates activated human NKT cells and enhanced human T cell responses to a viral peptide in vitro. Accordingly, we have demonstrated a means to safely exploit the immunostimulatory properties of NKT cells to enhance T cell activation for virus- and tumour-specific immunity.

The compact microstrip balun with wide stopband is proposed. This balun can be realized by integrating two short-circuited stepped coupled lines and two stepped impedance transformers. The electrical lengths of each stepped-coupled-line and each stepped-trans mission-line are a quarter wavelength. Moreover, by utilizing the weak-strong-weak coupling on the short-circuited stepped coupled line, a wide stopband will appear. Furthermore, the passband bandwidth can be broaden by adopting the stepped impedance transformer. In addition, the agreement between theoretical prediction and measurement validates the proposed structure.

A planar $4\times 4$ Butler matrix with a compact size is proposed. With the dual transmission lines, the proposed Butler matrix has arbitrary phase difference and phase delay for the used couplers and crossovers, respectively. In terms of experimental verification, the circuit size of the fabricated Butler matrix is $0.86\lambda_{g}\times 0.66\lambda_{g}$. In addition, the matched results between measurement and theoretical calculation can validate the proposed Butler matrix.

In this paper, a compact dual-wideband bandpass filter is presented. Based on the dual stepped-impedance rectangular-rings resonator, the bandpass filter with dual passbands can be realized. In order to obtain wide dual passbands, the high-impedance coupled lines are adopted for input and output ports to enhance the coupling. Moreover, with the assistance of open stubs added to the central transmission line, the harmonics can be suppressed and a wide stopband can be generated. An exemplary bandpass filter, operated at 2.5 and 7.25 GHz as the central frequencies, is fabricated, and both the corresponding 3-dB absolute bandwidths are the same as 1.5 GHz. In addition, the measured stopband can be extended to 13.8 GHz with the rejection level of 32 dB.

A 3-dB planar wideband power divider with an ultra-wide stopband and isolated frequency band is proposed. In order to extend the passband, the quasi-coupled lines are adopted. Moreover, the open and shorted stubs added at the input and output ports, respectively, can increase the bandwidths of the passband and stopband. Furthermore, in order to broaden the isolated frequency band, the impedance $Z _{\mathrm {iso}}$ with the series connected resister and capacitor on the right side of the middle coupled line is adopted. The detailed derivation is proposed as well. In addition, this power divider is fabricated on the substrate Rogers RO4003C with a compact size of 15.19 mm $\,\times \,11.4$ mm.

A major challenge in the development of highly defined synthetic vaccines is the codelivery of vaccine components (i.e., antigen and adjuvant) to secondary lymphoid tissue to induce optimal immune responses. This problem can be addressed by synthesizing vaccines that comprise peptide antigens covalently attached to glycolipid adjuvants through biologically cleavable linkers. Toward this, a strategy utilizing previously unreported 6″-deoxy-6″-thio analogues of α-GalCer that can undergo chemoselective conjugation with peptide antigens is described. Administration of these conjugate vaccines leads to enhanced priming of antigen specific T cells. This simple vaccine design is broadly applicable to multiple disease indications such as cancer and infectious disease.

A novel planar lowpass filter with a high attenuation and an ultra wide stopband is proposed. By using three radial stubs and one slotted pattern, seven transmission zeros appear in the stopband. Moreover, the stopband bandwidth of the lowpass filter can be conveniently altered by controlling characteristic impedances of the connecting lines and radial stubs. In order to validate the circuit design, a compact microstrip lowpass filter with the central frequency of 2.636 GHz and rejection level greater than 30 dB is fabricated. As a result, theoretical and measured results match well with each other, and the measured rejection bandwidth at 30 dB is 151.8%.

A microstrip dual-band Gysel power divider with arbitrary power division is proposed. In order to generate two frequency bands simultaneously, two Schiffman phase shifters are adopted. Moreover, these frequency bands with arbitrary power ratio between two output ports can be controlled by the transmission lines’ impedances $Z_{1}$ and $Z_{2}$ . In addition, with two $\pi$ -shaped transmission lines series connected at two output ports, there is prominent rejection between two passbands and a wide isolated frequency band between two output ports. Furthermore, two dual-band power dividers are developed to verify the proposed design.

Glycolipid–peptide conjugates designed to release vaccine components within target cells ensuring potent CD1d dependent T cell responses., It is known that T cells can eliminate tumour cells through recognition of unique or aberrantly expressed antigens presented as peptide epitopes by major histocompatibility complex (MHC) molecules on the tumour cell surface. With recent advances in defining tumour-associated antigens, it should now be possible to devise therapeutic vaccines that expand specific populations of anti-tumour T cells. However there remains a need to develop simpler efficacious synthetic vaccines that possess clinical utility. We present here the synthesis and analysis of vaccines based on conjugation of MHC-binding peptide epitopes to α-galactosylceramide, a glycolipid presented by the nonpolymorphic antigen-presenting molecule CD1d to provoke the stimulatory activity of type I natural killer T (NKT) cells. The chemical design incorporates an enzymatically cleavable linker that effects controlled release of the active components in vivo. Chemical and biological analysis of different linkages with different enzymatic targets enabled selection of a synthetic vaccine construct with potent therapeutic anti-tumour activity in mice, and marked in vitro activity in human blood.

Compact planar crossovers with a wide passband are proposed. By cascoding two quarter-wavelength branch-line couplers, a wide passband can be obtained. Moreover, the even-odd mode and the fourfold symmetry are adopted to derive the analytical equations. According to the derived formulas, the transmission lines' impedances Z 1 , Z 2 , and Z A , which may influence the performance of the operating fractional bandwidth (FBW), should be properly selected. In terms of experimental verification, the circuit size of the fabricated crossover is 0.23λ g × 0.23λ g . Moreover, the FBW of the developed crossover is the 59% 1-dB insertion-loss relative bandwidth corresponds to the S 31 parameter, whereas the 55% 15-dB one refers to the S 21 parameter. In addition, four bandstop filters can be added at four ports of the proposed crossover to achieve a wide stopband performance.

A compact tunable bandpass filter (BPF) with a broad stopband is presented. The proposed filter is composed of two modified coupled lines and one varactor-loaded stub. In terms of measurement, the tunable BPF with the transmission zero within the higher passband skirt has a very wide tuning range, from 0.95 to 1.55 GHz (48%). Moreover, with the return loss > 10 dB, there is a controllable constant passband bandwidth 120 MHz. Furthermore, within the tuning range, the insertion loss is from 2.4 to 2.8 dB and the return loss is > 20 dB.

The six-port crossover with the planar structure has been proposed. By utilizing double rings with quarter-wavelength branches, a wide passband can be obtained. With the proposed crossover, three intersecting channels with good performances of transmission and isolation can be generated. The even-odd mode and the six-fold rotational symmetry are adopted to derive the analytical equations. Moreover, the performances of diagonal transmission, port matching, and isolation between different channels are achieved with a fractional bandwidth of 13.5%, which has been demonstrated by the theoretical and measured results.

A compact and planar power divider with a wide passband and broad stopband is proposed. By using the coupled transmission lines for two output ports, the slope around the passband skirt will increase and the passband's bandwidth can be extended. Moreover, by inserting the open stubs at the input port and between two coupled transmission lines, a wide stopband can be obtained. An exemplary design of the power divider operated at 2 GHz is proposed. This power divider is fabricated on Rogers RO4003C with the size of 0.53 λ g × 0.52 λ g . Moreover, the measured fractional bandwidths in the passband and stopband are greater than 52.5% and 57.1%, respectively.

This study tests the hypothesis that CD8α(+) DCs in the spleen of mice contain an immature precursor for functionally mature, "classical" cross-presenting CD8α(+) DCs. The lymphoid tissues contain a network of phenotypically distinct DCs with unique roles in surveillance and immunity. Splenic CD8α(+) DCs have been shown to exhibit a heightened capacity for phagocytosis of cellular material, secretion of IL-12, and cross-priming of CD8(+) T cells. However, this population can be subdivided further on the basis of expression of both langerin/CD207 and CX(3)CR1. We therefore evaluated the functional capacities of these different subsets. The CX(3)CR1(+) CD8α(+) DC subset does not express langerin and does not exhibit the classical features above. The CX(3)CR1(-) CD8α(+) DC can be divided into langerin-positive and negative populations, both of which express DEC205, Clec9A, and high basal levels of CD86. However, the langerin(+) CX(3)CR1(-) CD8α(+) subset has a superior capacity for acquiring cellular material and producing IL-12 and is more susceptible to activation-induced cell death. Significantly, following purification and adoptive transfer into new hosts, the langerin(-) CX(3)CR1(-) CD8α(+) subset survives longer, up-regulates expression of langerin, and becomes more susceptible to activation-induced cell death. Last, in contrast to langerin(+) CX(3)CR1(-) CD8α(+), the langerin(-) CX(3)CR1(-) CD8α(+) are still present in Batf3(-/-) mice. We conclude that the classical attributes of CD8α(+) DC are confined primarily to the langerin(+) CX(3)CR1(-) CD8α(+) DC population and that the langerin(-) CX(3)CR1(-) subset represents a Batf3-independent precursor to this mature population.

This study develops a microstrip bandpass filter with a broader stopband. The proposed bandpass filter is constructed by cascading three stepped coupled lines and two short-circuited stubs. Moreover, quarter-wavelength electrical lengths and weak strong-weak couplings are adopted for the stepped coupled line. In this way, a compact circuit size and a wide stopband can be achieved readily. In addition, the short-circuited stubs connected to the input/output port can result in a steeper passband skirt and a broader passband. Finally, a design example is provided to show the availability of the proposed structure. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2283–2286, 2014

Novel design equations are proposed for the 3-dB microstrip branch-line coupler with a wide passband, utilizing multisectional branch lines. In addition, the proposed method makes it possible to reduce the internal impedance levels of branch-line couplers so they may be physically constructed by microstrip lines. Further, in terms of measured results, there is a wide bandwidth >70%. Synthesis of the 3-dB branch-line coupler is described in details as well. Good agreement between theoretical calculation and measurement validates the proposed method.

A compact notch filter with a wide tunable frequency range is developed. This tunable filter is composed of two varactor-tuned resonators, shunted at input/output ports separately, and one quarter-wavelength transmission line connecting two varactor-tuned resonators. By enlarging impedance of the quarter-wavelength transmission line, the proposed tunable filter can obtain a wide and constant absolute bandwidth within the whole tunable frequency band. The measured results show that there is a wide tuning range, 124.3%. In addition, with insertion loss greater than 20 dB, a wide constant absolute bandwidth can be achieved at 450 MHz.

Novel wide passband microstrip bandpass filters with broader stopbands are provided in this paper. The proposed bandpass filters are composed of the stepped coupled line and two short-circuited stubs. The electrical length of the stepped coupled line is a quarter of wavelength so that the proposed filter is compact size. Moreover, the stepped coupled line with weak-strong-weak coupling results in a wide stopband. Furthermore, with short-circuited stubs connected at the input/output port, there is a steeper passband skirt and broader passband. In addition, the agreement between theoretical prediction and measurement validates our proposed structure.

Complex impedance transformers with the modified coupled line are provided in this paper. With the modified coupled line as proposed, the electrical length of the impedance transformer would be smaller than a quarter wavelength. In addition, analytic equations for the design of complex impedance transformers are derived; optimal characteristic impedance and impedance transformation are also calculated for successful power transfer. Simulation and measurement have demonstrated transformation efficiency and the potential for application of the proposed structure to radio frequency and microwave circuits.

A compact planar crossover with two intersecting channels is proposed. This crossover is constructed by a patch resonator and two cross-slotted lines. Moreover, the longer the cross slotted lines are, the smaller the proposed planar crossover is. In order to simplify the analysis of the proposed planar crossover, the approximate two-port equivalent circuit is provided. The measured performances match well with the theoretical results, which validates the proposed circuit.

A planar power divider with a ultra-wide stopband and isolated frequency band is proposed. In this paper, the quasi-coupled lines are adopted to extend the passband. Moreover, the open and shorted stubs added at the input and output ports, respectively, can increase the bandwidths of the passband and stopband. Furthermore, in order to broaden the isolated frequency band, the impedance Ziso with the series connected resister and capacitor on the right side of the middle coupled line is adopted. This power divider is fabricated on the substrate Rogers RO4003C, with a compact size of 15.19 mm × 11.4 mm.

Poly ethoxy ethyl glycinamide (PEE-G) dendrimers have been specifically designed and synthesized with the aim of providing a readily available dendrimer scaffold that can be used to make products that can meet the stringent requirements of pharmaceutical applications. The synthesis has been refined to produce dendrimers that are of high HPLC purity. The suitability of PEE-G dendrimers for their designed use has been verified by subsequent measurements to demonstrate that they are of high stability, high aqueous solubility, low cytotoxicity, low immunogenicity and with low in vivo toxicity in an escalating-dose rat study. PEE-G dendrimers therefore provide a useful scaffold for researchers wanting to develop dendrimer-based drug candidates.

A novel compact tri-passband bandpass filter is proposed and developed. The proposed filter consists of two hexagonal grounded resonators, one rectangular slot, and two hexagonal patches. The resonators, slot and patches can control three passbands with 3, 5.5, and 9.4 GHz for central frequency, respectively. The equivalent circuit and design procedures of the tri-passband bandpass filter are provided as well.

A compact microstrip bandpass filter with a wide passband and broad stopband is proposed. In order to miniaturize the circuit size, the interdigital capacitor is adopted. Moreover, the open- and short-circuited coupled lines are also employed to generate the transmission zeros around the passband skirts. This bandpass filter is developed at 2.45 GHz for the central frequency. The measured bandwidth is 45% with 10-dB for the return loss. Furthermore, the stopband can be extended to 11.7 GHz (4.8ƒ0) with 27 dB for the suppression. In addition, the circuit size is 0.14λg × 0.15λg.

A microstrip crossover with dual passbands is proposed. With the asymmetrical n-shaped transmission lines inserted into the window-shaped crossover, a wide and flexible operating frequency ratio can be obtained. Consequently, the even- and odd-mode analysis and the fourfold symmetry are adopted to derive the design equations. In order to validate the proposed structure, a crossover with a compact size, 0.38λg × 0.38 λg is fabricated.

A compact dual-band bandpass filter is proposed in this paper. This dual-band bandpass filter consists of a 50-μ microstrip line with U-shaped slots on the top layer and two pairs of folded stepped impedance resonators (SIRs) with defected ground structure (DGS) on the bottom layer. The central frequency of the first passband, 3.7 GHz, is determined by the first pair of the DGS-SIR resonators; the central frequency of the second passband, 5.7 GHz, depends on the second pair of the DGS-SIR resonators. In addition, the proposed filter is fabricated on the substrate RO4003C, with the size of 46 mm × 18 mm. As for the measured results, with 3.7 GHz and 5.7 GHz for central frequencies, the insertion losses are 1.8 dB and 2.1 dB, respectively. Moreover, the measured return losses are 16.5 dB and 18.51 dB, respectively.

A broadband balun with the compensated coupled line at balanced ports has been proposed. The operating fractional bandwidth of the proposed balan is 10% more than that of the conventional Marchand balun. Moreover, the proposed method can be employed for a long connecting segment between the balanced ports with tight coupling at desired frequencies. In addition, summarized graphs are provided as well. Furthermore, a design example is developed to demonstrate the flexibility of the proposed structure.