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Modern communication systems have traditionally exploited three parts of the electromagnetic spectrum: radio waves region, infrared region and visible region, where the evolution in these ranges is always accompanied by the appropriation of new electromagnetic phenomena to build devices with better characteristics. In these three regions great advances have been conducted in recent years. For this reason, in this issue, we call for papers concerning to the major challenges that these technologies may face in the coming years.

Dielectric Ba0.6Sr0.4TiO3 (BST) thin films with a different concentration of Ag-dopant of 0.5, 1, 1.5, 2, 3, and 5 mol % have been prepared using an alkoxide-based sol-gel method on a Pt(111)/TiO 2/SiO2/Si substrate and their surface morphology and crystallinity have been examined using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis, respectively. An on-chip metal-insulator-metal capacitor has been fabricated with the prepared thin film ferroelectric sample. Concentric coplanar electrodes are used for high frequency electrical characterization with a vector network analyzer and a probe station. The SEM images show that increasing Ag doping concentration leads to a decrease in grain size. XRD reveals that the fabricated films show good BST crystallinity for all the concentration while a doping concentration of 5 mol % starts to show an Ag peak, implying a metallic phase. Improved microwave dielectric loss properties of the BST thin films are observed in a low Ag doping level. Especially, BST with an Ag doping concentration of 1 mol % shows the best properties with a dielectric constant of 269.3, a quality factor of 48.1, a tunability at the electric field of 100 kV/cm of 41.2 %, a leakage-current density of 1.045 × 10- 7A/cm2 at an electric field of 100 kV/cm and a figure of merit (defined by tunability (%) divided by tan δ (%)) of 19.59 under a dc bias voltage of 10 V at 1 GHz. © 2014 Elsevier B.V. All rights reserved. This work was supported by the Global R&D program of MOTIE/KIAT (N0000686)

A millimeter-wave two-pole bandpass filter (BPF) with an asymmetrical frequency response is realized on a flexible liquid crystal polymer substrate for wearable/conformal wireless applications. The design uses the triangular-shape quarter-mode substrate integrated waveguide (QMSIW) cavity loaded with a complementary split-ring resonator. The compact cavity shows a resonant mode below the quasi-TE1,0,0.5 mode of an original QMSIW cavity, which indicates a further size reduction. In addition, its low quality factor (Q) is useful for BPFs with broad fractional bandwidth (FBW). A surface micromachined two-pole Chebyshev BPF is realized for operation at 35 GHz with a 20 dB return loss FBW of 8% and an insertion loss of 1.7 dB. © 2015 Wiley Periodicals, Inc. National Science Foundation, NSF: 1132413

A new wearable RF plethysmography (RPG) sensor is developed to monitor wrist pulse rate and variability. System design, numerical simulations, fabrication and measurements were carried out to demonstrate the performance of the plethysmography sensor. The RF sensor detects not only pulse rate but also modulations within each pulse. Clear detection of three modulations indicate that the RF plethysmography signals can be used for diagnosing different health conditions. A cavity based H-slot antenna is designed as a near field sensor. Two transmit and receive architectures based on conventional coupler/power combiner and innovative differential LNA approaches are designed in order to improve sensitivity of pulse detection. Both these architectures are based on the principle of isolation of the reflected signal from the transmitted signal. It is observed that the present RPG sensors perform better than the commercially available PPG sensor.

The analysis of the performance of wireless power transfer (WPT) systems that use a planar array of magnetic metamaterial (MM) resonators embedded in the transmitter and receiver loop coils is presented. A high quality factor (Q) multiturn planar spiral loaded with a chip capacitor is used to create a compact subwavelength metamaterial unit cell, which shows a better control of the WPT system resonance frequency and overall Q factor than conventionally used self-resonance coils. Cases with one unit cell, 2×2 and 3×3 MM arrays are investigated. The measured results show a stable power transfer with up to 78% power transfer efficiency (PTE) at a distance of 3 cm for a 3×3 array. The results show that planar lumped element based embedded metamaterial slabs in the transmitter (Tx) and receiver (Rx) help improve the PTE for resonant inductive and non-resonant WPT systems.

This paper presents a wrist wearable wireless plethysmography sensor based on the variation of reflection coefficient (S11) of a planar H-slot antenna and a compact, efficient signal processing circuit. The sensor detects changes in the volume of human blood in the radial artery and reflects it as a change in the reflection coefficient, and hence a change in the body pulse waveform. The sensor is designed to operate at 2.4 GHz ISM band. A salient feature of the present work is improved sensitivity through slot antenna and an efficient T/R architecture with better SNR design.

Two highly compact tunable stopband filters using microstrip transmission lines coupled with split ring resonators (SRRs) and varactor diodes are presented. Frequency or bandwidth tuning capability of each device is demonstrated. The frequency tunable filter, realized by a single stage, shows a wide tuning range of 19.8% with a maximum bandwidth of 5% and an insertion loss of approximately 20 dB at 4 GHz. The bandwidth tunable filter, realized by double stages, shows a 10-dB bandwidth of 19–34% with a biasing voltage of 0–10 V. The implemented frequency tuning and bandwidth tuning devices show a significant area reduction of 60.1% and 53.5%, respectively, in comparison with a similar frequency or bandwidth tunable structure presented by others. Equivalent circuit models are presented. The measured S -parameters are in good agreement with simulated ones.

An inductively loaded compact patch antenna for a radiation frequency of 433 MHz is designed taking into consideration a human-body model and fabricated on a flexible liquid crystalline polymer (LCP) substrate, which is subsequently wrapped into a cylindrical shape to achieve a monopole-like omnidirectional radiation pattern for wireless endoscope applications. The wrapped patch antenna has a stretched length of 31 mm (0.07λ), and its cylindrical form has a diameter of 10 mm and a width of 18.5 mm, whose dimensions are designed to be comparable to those of a commercially available capsule endoscope. Compared to a traditional patch antenna with the same radiation frequency, an 86% length reduction is achieved. Omnidirectionality is desired to increase the space coverage in communication between the randomly moving capsule inside and the receiver outside the body. The enclosed cylindrical cavity, surrounded by the ground plane of the patch, provides an electromagnetic interference (EMI) protected room that is useful for the placement of other electronic components. Multiple inductive notches on a patch designed for antenna size reduction are described by an equivalent circuit model. Human-body phantom solution is used for antenna characterization. The antenna, located at the outermost layer, serves not only as a good radiating unit, but also as the EMI protecting, mechanically supporting, packaging layer of the endoscope system. © 2002-2011 IEEE.

A patch loaded with a complementary split-ring resonator (CSRR) is fabricated on a flexible substrate and folded in a cylindrical shape, forming a self-packaged folded patch antenna with a quasi-omnidirectional radiation pattern. The space inside the cylindrical cavity is electromagnetically shielded by the ground plane of the patch, and therefore electronic circuits can be accommodated in it with little electromagnetic interference (EMI) from the antenna or other external electronics. The CSRR contributes to size reduction. As a test vehicle, a 2.4-GHz ISM-band folded patch antenna is designed, fabricated, and characterized for a wireless capsule endoscope application, where the implemented antenna has a patch length of 10.5 mm (0.11λ ) and a folded cylinder diameter of 10 mm. A 74% size reduction is achieved after CSRR loading. The antenna located at the outermost surface not only functions as an electromagnetic radiator and an EMI shield, but also serve as a mechanical packaging structure.

An analysis of the electrical performance of a microstrip patch antenna loaded with a periodic array of metamaterial resonators is presented in this work. Hexagonal complementary split ring resonators (CSRRs) are selected as metamaterial particles to be embedded in a conventional patch antenna. Geometrical parameters of the array of resonators are varied in order to evaluate the frequency response and radiation performance of the proposed antenna. A reduction of 5.7% in the resonance frequency is achieved with the metamaterial inclusions, while the return loss are improved to a value of -34 dB for 2GHz. The radiation performance is unchanged while the gain of the antenna is increased. Simulation and measured results are presented and show that the metamaterial array allows size reduction and gain improvement. © 2016 IEEE. The Institute of Electrical and Electronics Engineers IEEE Antennas and Propagation Society

In this work, we report on in-substrate passive components using a high performance glass interposer and through glass via (TGV) technology and a multi-layer superlattice conductor architecture. Minimal RF loss is achieved using low dielectric loss glass substrates and superlattice conductors featuring skin effect suppression. Half mode substrate integrated waveguide (HMSIW) resonators and two-pole bandpass filters, embedded inside a glass interposer substrate, are used as test vehicles for the demonstration of insertion loss improvement in K-band. The utilized conductor is made of 20 layers of Cu/NiFe with each pair of 360 nm/30 nm, respectively, where NiFe layers with negative permeability in frequency range of interest are used for eddy current cancelling and improving the conductor loss. Control devices using the same glass substrate and conductor made of pure copper are fabricated for comparison purposes. The glass interposer substrate (SGW3, Corning Incorporated) has a thickness of 0.13 mm and the TGV's with a diameter of 0.08 mm. Up to 0.3 dB reduction in the insertion loss is achieved by using the proposed superlattice approach on glass substrates. © 2016 IEEE. IEEE Components, Packaging, and Manufacturing Technology (CPMT) Society

A millimeter-wave bandpass filter (BPF) using complementary split-ring resonator (CSRR) loaded quarter-mode substrate integrated waveguide (QMSIW) cavities is presented in this work. The CSRR-loaded QMSIW cavity resonates below the original QMSIW resonance frequency, which further reduces the size with respect to its SIW counterpart. The reduced quality factor Q of the cavity makes it useful for BPFs with broad fractional bandwidth (FBW). A micromachined 4th order Chebyshev BPF is demonstrated at the unlicensed 57 GHz to 64 GHz frequency band. A FBW of more than 11.6% with an in-band return loss of better than 15 dB, and an insertion loss of less than 2.5 dB are obtained. © 2014 IEEE.

In this paper the flexible Liquid Crystal Polymer (LCP) substrate is used to implement broadband wearable/foldable conformal bandpass filters that use compact cavity resonators working under the principle of quarter mode substrate integrated waveguide (QMSIW), which features a 75% size reduction with respect to the conventional substrate integrated waveguide (SIW) counterpart. Further size reduction is realized with the use of a complementary split ring resonator (CSRR) metamaterial unit cell integrated with the QMSIW architecture. The resulting CSRR-loaded QMSIW cavity has its main resonance frequency below the quasi-TE0.5,0,0.5 resonance mode of the original QMSIW cavity due to the evanescent wave amplification phenomenon with CSRR loading. A low temperature surface micromachining process on the LCP and mechanical drilling of via holes are used for fabrication. The realized CSRR-loaded QMSIW cavity features a moderate quality factor (Q) that makes it useful for the design of bandpass filters with much broader fractional bandwidth (FBW) when compared to those using conventional SIW cavities. A 2nd order and a 3rd order surface micromachined Chebyshev BPFs are demonstrated for operation at a center frequency of 25.5 GHz. More than 11% FBW with an in-band return loss of better than 20 dB and an insertion loss of less than 1.5 dB, including transitions, are obtained for both filters. Theoretical analysis of the working principle is explained. Measured results are in good agreement with the 3D full wave structure simulations. © 2014 IEEE. IEEE Components, Packaging, and Manufacturing Technology Society (CPMT)

High quality and compact RF devices, using the half mode substrate integrated waveguide (HMSIW) architecture loaded with a complementary split ring resonator (CSRR), are implemented on a glass interposer layer, which therefore serves as an interconnection layer and as a host medium for integrated passive RF components. Compared with the silicon interposer approach, which suffers from large electrical conductivity and therefore substrate loss, the glass interposer has advantages of low substrate loss, allowing high quality interconnection and passive circuits, and low material and manufacturing costs. Corning fusion glass is selected as the substrate to realize the compact CSRR-loaded HMSIW resonators and bandpass filters (BPFs) working under the principle of evanescent wave amplification. Two and three pole bandpass filters are designed for broadband operation at 5.8 GHz. Thru glass vias (TGVs) are used to define the side-wall of the substrate integrated waveguiding structure. Surface micromachining techniques are used to fabricate the proposed devices. The variations of the external quality factor (Qe) of the resonator and the internal coupling coefficient (M) of the coupled resonators are studied for filter design. Operation of the filters at 5.8 GHz with a fractional bandwidth (FBW) of more than 10% for an in-band return loss of better than 20 dB and an low insertion loss of less than 1.35 dB has been obtained, which is not feasible with a usual Si interposer approach. Measurement results are presented from 2 to 10 GHz and show good agreement with simulated ones. © 2014 IEEE. IEEE Components, Packaging, and Manufacturing Technology Society (CPMT)

The substrate integrated waveguide (SIW) is analyzed as an Epsilon Negative transmission line for the design of dual band dual mode antennas. The dual band design is feasible by exciting an open ended SIW to produce the zeroth order resonance (ZOR) or infinite wavelength mode at the cutoff frequency where a zero permittivity point is presented, and the first order resonance occurring at a frequency where the length of the waveguide is a half of the guided wavelength. A new design procedure is demonstrated using the theoretical analysis of the SIW. A miniaturized dual band antenna working at 10/17 GHz frequency bands is implemented and characterized. The proposed design procedure has been confirmed. The antenna features a compact size of 0.35λ0 × 0.2λ0 at 10 GHz.

Novel dual-band bandpass filters are implemented for 3.5GHz and 5.8GHz operation by using the half-mode substrate integrated-waveguide (HMSIW) loaded with a complementary split-ring resonator (CSRR) and a capacitive metal patch. Forward electromagnetic wave transmission below the characteristic waveguide cutoff frequency is achieved at two arbitrary frequency bands. Relatively independent control of the resonance frequencies, external Q factor and mutual coupling are possible. A dual band resonator and a two-pole miniaturized bandpass filter are demonstrated. The external and internal mutual coupling variations are fully investigated. Full wave structure simulation and measurement results are provided.

A surface micromachined high gain dielectric lens antenna (DLA) for millimeter wave applications is designed, fabricated, and characterized. The designed DLA consists of a conductor-backed coplanar waveguide (CBCPW) fed coplanar patch antenna and a lens made of photopatternable epoxy, SU8, and supported by polydimethylsiloxane (PDMS). The antenna has a broad bandwidth of 6 % and a high gain of 7.54 dBi at 77 GHz.

Electrically tunable evanescent mode half mode substrate integrated waveguide (HMSIW) resonators are implemented for S band applications. An HMSIW loaded with a complementary split ring resonator (CSRR) achieves forward electromagnetic wave transmission below the characteristic waveguide cutoff frequency due to evanescent wave amplification. A variable capacitor connected to one of the conductors of the CSRR changes its effective capacitance to ground, resulting in frequency tuning of the resonator. Three different configurations are investigated with a varactor diode connected between the ground and three different contact points of the CSRR. The external Q factor is slightly affected by the frequency tuning. More than 15% tunability is achieved around 3.4 GHz. Full wave structure simulation results are in good agreement with those of measurement. © 2006 IEEE. Manuscript received September 27, 2011; revised December 15, 2011; accepted January 05, 2012. Date of publication February 24, 2012; date of current version March 14, 2012. This work was supported by the U.S. National Science Foundation Grant ECCS 1132413.

Two linear arrays of split ring resonators (SRR) with broad side coupling and various relative positions are investigated for controllable wave transmission in a rectangular waveguide. Each array is designed to have a different unit size of SRRs. A rectangular waveguide with a cutoff frequency of 3.2 GHz shows an additional stopband between 3.4 GHz and 4.8 GHz when a five element SRR array with a unit SRR dimension of 18mm by 18 mm and a pitch of 25mm is loaded. The other five element array with a unit dimension of 10mm by 10mm and a pitch of 25mm is inserted adjacent to the first array with a broad side coupling resulting in another stopband between 5 GHz and 6.5 GHz, where the coupling gap between two arrays is approximately 3mm (120mil) and the dielectric constant is 2.55. The center frequency of the stopband is tunable depending on the degree of alignment between those two arrays. One of the SRR arrays has a piece of magnet attached to its edge, and in-situ tuning is achieved by moving it by a ferrite (or a permanent magent) from outside of the waveguide. The tuning results of numerical simulation show good agreement with those of measurement.

A self-packaged folded patch antenna in a rectangular waveguide shape is greatly reduced in size by loading a complimentary split ring resonator (CSRR) on the edge of its ground plane. The dimensions of the proposed antenna are 15mm×15mm×20mm, showing 72% volume reduction compared to one without CSRR loading at the same radiation frequency of 2.4GHz. Impedance matching between the patch and the feeding line is obtained by adjusting the gap between two edges of the folded patch not necessitating an additional impedance matching circuit. Also, the inside cavity surrounded and packaged by the folded patch is electromagnetically well shielded from the external circuit. This antenna offers a quasi-omni-directional radiation pattern. All those features make the proposed antenna very suitable for a compact sensor network application. To our knowledge, this is the first report a non-planar CSRR applied to antenna size reduction.

A self-packaged antenna obtained by folding a normal patch antenna into rectangular waveguide shape has been recently reported by the authors. In this work, by applying electric vias at the edge of the folded patch as well as inductive dents on the edge, the folded antenna dimension is greatly reduced. At the same radiation frequency of 2.4GHz, the vertical length of the newly proposed antenna is reduced from 40mm to 19mm which is 52.5% size reduction. The cross section area is 20mm × 20mm. Since this architecture allows PCB layout or other electronics inside the cavity of the folded antenna, it is considered a self-packaged structure. If designed carefully, this antenna may take zero footprint and offers electromagnetic interference shielding to the PCB enclosed in its cavity. Meanwhile, this antenna does not require additional impedance matching circuits, which makes it very useful for compact devices. A quasi-omni-directional radiation pattern is obtained. Theoretical analysis, numerical simulation, fabrication and measurement are performed. Good agreement is observed between simulation and measurement data.

Three dimensional (3-D) nanofabrication using the dynamic mode multidirectional ultraviolet (UV) lithography has been explored, where the size of the photomask pattern is compatible to or smaller than the wavelength of the UV source and therefore the diffraction effect is prominent in photopatterning. Ray trace taking into account the effect of refraction, diffraction, and absorption has been simulated using an optical numerical analysis tool (COMSOL, Inc.). Subwavelength patterning with a pattern diameter of 300nm has been performed on a chromium coated glass substrate using E-beam lithography to form a photomask. A thin layer of SU-8, a negative tone photoresist, with a thickness of 1∼10 microns has been coated on the photomask and multidirectional UV lithography is performed through the mask, where the photomask servs as a substrate as well. Nanoscale pillars with a pattern diameter of 300nm have been fabricated with different optical doses and simulation results show good correlation with simulation results in terms of the shape and the height. Various 3-D structures including an inclined pillar array, a vertical triangular slab, a tripod embedded horn, and a triangular slab embedded horn have been successfully fabricated. A vertical triangular slab array has been demonstrated for a terahertz (THz) selective surface application.

A corrugated substrate integrated waveguide (SIW) with dual non-Bragg resonance frequencies at 4.8 GHz and 8 GHz is presented, where the two sidewalls of the SIW are not straight but corrugated in sinusoidal shape. Theory has been described and backed up by numerical simulation. In addition, test devices are fabricated and characterized. The measurement results show good agreement with those of theoretical calculation and simulation. Design parameters for dual bands include the amplitude and period of the corrugations, and the phase difference between two corrugation boundaries. The presented architecture has flexibility for broadband or multi-band applications. Design guidelines are discussed.

The Electrospinning and Stamp-thru-mold (ESTM) technique, an integrated fabrication process which incorporates the versatility of the electrospinning process for nanofiber fabrication with the non-lithographic patterning ability of the stamp-thru-mold process is introduced. In-situ multilayer stacking of orthogonally aligned nanofibers, ultimately resulting in a nanoporous membrane, has been demonstrated using orthogonally placed collector electrode pairs and an alternating bias scheme. The pore size of the nanoporous membrane can be controlled by the number of layers and the deposition time of each layer. Nonlithographic patterning of the fabricated nanoporous membrane is then performed by mechanical shearing using a pair of pre-fabricated micromolds. This patterning process is contamination free compared to other photo lithographical patterning approaches. The ability to pattern on different substrates has been tested with and without oxygen plasma surface treatment. In vitro tests of ESTM poly-lactic-co-glycolic acid (PLGA) nanofibers verify the biocompatibility of this process. Simulation by the COMSOL Multiphysics tool has been conducted for the analysis of electrospun nanofiber alignment.

In this work, an evanescent mode half mode substrate integrated waveguide (HMSIW) resonator is designed for a wireless passive sensing application at 5 GHz. The wireless pressure sensor has been implemented by placing a small Polydimethylsiloxane (PDMS) cavity, covered with a metal coated membrane, on top of the original resonator or by using a cavity ground plane. When the metal coated membrane is deformed or deflected by an external pressure, it perturbs the electric field of a complementary split ring resonator (CSRR) patterned on top of the HMSIW, producing a shift in the resonance frequency. Because it operates in a microwave frequency spectrum, it offers a high pressure-frequency sensitivity. Resonance frequency as a function of an applied pressure has been presented. Also, a broadband antenna has been integrated to perform wireless interrogation of the sensor. © 2011 IEEE.

A disease syndrome similar to the hemolytic uremic syndrome of people is described in three dogs with acute renal failure. In each dog, hemorrhagic gastroenteritis preceded the onset of anuric acute renal failure. Evidence of microangiopathic hemolytic anemia (schizocytes, thrombocytopenia, and increased concentrations of fibrin split products) was present in the three dogs. Serum chemistry results showed increased concentrations of blood urea nitrogen, creatinine, and phosphorus. Ultrasound examination performed in one dog revealed increased echogenicity of the renal cortices. Treatment for anuric acute renal failure using a continuous dopamine and furosemide infusion established urine production in one of three dogs. Microscopic examination of tissue from the two dogs that underwent necropsy showed occlusion of the renal vasculature by fibrin thrombi consistent with microangiopathic arteriolar thrombosis. The pathophysiology and current knowledge of human hemolytic uremic syndrome is compared with hemolytic uremic syndrome in these dogs.

Electromagnetic (EM) wave propagation in periodic structure is an interesting research topic in electronic, optical and laser systems. Conventionally, wave propagation in periodic media can be characterized by the Bragg's law where the resonance frequency can be determined by the periodicity of the media and a wave incident angle. However, there is also a kind of non-Bragg resonance which cannot be characterized by the traditional Bragg's law. A non-Bragg resonance has been observed in a rectangular waveguide with corrugated walls by the Cheng et al. [1]. The resonance frequency depends on the waveguide height (or thickness), the periods and amplitudes of the corrugations, and a phase shift between the corrugated walls. Since non-Bragg resonance only occurs under specific geometric conditions, it is also known as geometric resonance [1].

High performance microwave bandpass filters with low insertion loss, high selectivity, compact size and multiple bands are widely used for wireless and satellite communication systems [1]. During the years, bandpass waveguide filters have used all kinds of metallic and non-metallic insertions in order to improve performance and reduce size [2]. Since the first experimental demonstrations of metamaterial particles exhibiting either negative permeability such as the split ring resonators (SRR), or negative permittivity such as the complementary split ring resonators (CSRR), different implementations combining waveguide with such structures have been widely investigated for bandpass filters [3–4], mainly motivated by their extraordinary property of generating backward wave transmission below the waveguide cutoff frequency. On the other hand, the need for new applications and integration with digital circuitry is the motivation for proposing and implementing planar microwave filters with performances similar to those provided by the bulky waveguide filters. The substrate integrated waveguide (SIW) and the half mode substrate integrated waveguide (HMSIW) [5–6] have been selected as the key wave guiding structures for the implementation of low loss, high quality factor and improved selectivity waveguide bandpass filters on printed circuit board (PCB) technology. In addition, taking into account the possibility of having forward wave propagation below the waveguide cutoff frequency, the substrate integrated waveguide has been combined with complementary split ring resonators (CSRR) for the implementation of compact size and high selectivity bandpass filters [7].

Retrograde nephrostomy, a new technique to aid in stone management, has been performed successfully in dogs. It has also been used without complication in a human patient to help remove a renal stone percutaneously under local anesthesia. The technique consists of placing a coaxial catheter over a guidewire under fluoroscopy into the exact calyx desired and advancing a long needle out to the skin to establish a transcutaneous tract. The advantages of the technique include increased control and precision of tract placement, efficient working angles for percutaneous stone removal, and the ability to perform the procedure under local anesthesia.

The introduction of extracorporeal shock wave lithotripsy (ESWL) has provided an avenue for dealing with many urinary stones noninvasively. The margin of safety for the kidney during shock wave administration is largely undefined. A pilot study was performed where six kidneys in five female mongrel dogs were shocked. Group A kidneys were given 1,776, 4,500, 6,000, or 8,000 shocks, respectively, at 18-24 kV. Group B kidneys received 1,600 and 8,000 shocks (18-24 kV). The number of shocks per electrode ranged from 500 to 4,538 and averaged 2,490. The dogs were sacrificed forty-eight to seventy-two hours (Group A) or twenty-eight to thirty-two days (Group B) post-treatment. Modest damage (hematoma and/or interstitial hemorrhage) was noted in all kidneys. Evidence of permanent change (fibrosis) was noted in both Group B kidneys. Complete necrosis of the kidney was not seen after administration of 8,000 shocks. These preliminary data indicate that lithotripsy can, in some circumstances, produce renal damage in the canine model.

High throughput nanomanufacturing of photopatternable nanofibers and subsequent photopatterning is reported. For the production of high density nanofibers, the tube nozzle electrospinning (TNE) process has been used, where an array of micronozzles on the sidewall of a plastic tube are used as spinnerets. By increasing the density of nozzles, the electric fields of adjacent nozzles confine the cone of electrospinning and give a higher density of nanofibers. With TNE, higher density nozzles are easily achievable compared to metallic nozzles, e.g. an inter-nozzle distance as small as 0.5 cm and an average semi-vertical repulsion angle of 12.28° for 8-nozzles were achieved. Nanofiber diameter distribution, mass throughput rate, and growth rate of nanofiber stacks in different operating conditions and with different numbers of nozzles, such as 2, 4 and 8 nozzles, and scalability with single and double tube configurations are discussed. Nanofibers made of SU-8, photopatternable epoxy, have been collected to a thickness of over 80 μm in 240 s of electrospinning and the production rate of 0.75 g/h is achieved using the 2 tube 8 nozzle systems, followed by photolithographic micropatterning. TNE is scalable to a large number of nozzles, and offers high throughput production, plug and play capability with standard electrospinning equipment, and little waste of polymer. © 2017, The Author(s).