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Wide-angle coverage, fine angular resolution, and low-power consumption are the key characteristics of millimeter-wave short-range wireless systems, such as access points in fifth-generation cellular networks and automotive radars. In this paper, we present a 60 GHz switched-beam antenna system addressing all these requirements. It consists of two identical parallel-fed arrays of eight slots, each fed by a passive pillbox beamformer. A switch network comprising four single-pole-multiple-throw switches excites one of the two arrays at a time and selects the radiated beam. The whole system is fully integrated into a multilayer low-temperature cofired ceramic module. The antenna covers a scan range of about ±39° in one plane using 11 beams between 57 and 66 GHz. The proposed architecture enables the simultaneous achievement of continuous coverage (beam crossover levels of about −3 dB) and of low sidelobe levels. Dedicated numerical tools are used for a preliminary design of the antenna. The design procedure, the technological development, and the experimental results are discussed in detail. [ABSTRACT FROM AUTHOR]

A millimeter-wave communication system needs a directive beam-steering antenna with a low scan loss to compensate the high free space loss. In this letter, an electronically beam-switching integrated lens antenna (ILA) system with low scan loss is designed for lower E-band (71–76 GHz). An ILA with hemispherical collimating surface of 26 mm radius and spherical feed surface of 37.5 mm radius is fabricated from Teflon material. A conformal 1 × 16 linear beam-switching feed array based on SP4T switches and Vivaldi antennas is designed. The maximum simulated and measured realized gain including the switch network losses is 21.8 and 19.6 dBi, respectively. The measured scan loss of the ILA excluding the switch network loss is less than 1.3 dB in the lower E-band for beams within $\pm$ 40°. [ABSTRACT FROM AUTHOR]

The new services available through smart devices require very high cellular network capacity. The capacity requirement is expected to increase exponentially with the forthcoming 5G networks. The only available spectrum for truly wideband communication (>1 GHz) is at millimeter wavelengths. The high free space loss can be overcome by using the directive and beam-steerable antennas. This paper describes a design and the measurement results for a lens antenna system for $E$ -band having 2-D beam-steering capability. Continuous beam-switching range of about \pm 4 {^{\circ }} \times \pm 17^{\circ } is demonstrated with the lens having the maximum measured directivity of 36.7 dB. Link budget calculation for backhaul application using the presented lens antenna system is presented and compared with the measurement results of the implemented demo system. [ABSTRACT FROM PUBLISHER]

Background Many children with permanent brachial plexus birth injury (BPBI) develop shoulder problems, with subsequent joint deformity without treatment. We assessed the indications and outcome of shoulder operations for BPBI. Patients and methods 31 BPBI patients who had undergone a shoulder operation in our hospital between March 2002 and December 2005 were included in the study. Relocation of the humeral head had been performed in 13 patients, external rotation osteotomy of the humerus in 5 patients, subscapular tendon lengthening in 5 patients, and teres major transposition in 8 patients. Subjective results were registered. Shoulder range of motion was measured, and function assessed according to the Mallet scale. Magnetic resonance imaging (MRI) was performed pre- and postoperatively. Glenoscapular angle (GSA) and percentage of humeral head anterior to the middle of the glenoid fossa (PHHA) were measured. Congruency of the glenohumeral joint (GHJ) was estimated. The mean follow-up time was 3.8 (1.7-6.8) years. Results At follow-up, the subjective result was satisfactory in 30 of the 31 patients. There were 4 failures, which in retrospect were due to wrong choice of surgical method in 3 of these 4 patients. Mean increase in Mallet score was 5.5 after successful relocation, 1.4 after rotation osteotomy, 2.2 after subscapular tendon lengthening, and 3.1 after teres major transposition. Congruency of the shoulder joint improved in 10 of 13 patients who had undergone a relocation operation, with mean improvement in GSA of 33º and mean increase in PHHA of 25%. There were no substantial changes in congruency of the glenohumeral joint in patients treated with other operation types. Interpretation Restriction of the range of motion and malposition of the glenohumeral joint can be improved surgically in brachial plexus birth injury. Remodeling of the joint takes place after successful relocation of the humeral head in young patients. [ABSTRACT FROM AUTHOR]

A reader module at 60 GHz for high data-rate short-range backscattering-based communications is presented. The reader consists of a CMOS-based oscillator, amplifiers, and a mixer on a low-temperature co-fired ceramic (LTCC) substrate. The filter, power splitter, and antennas are directly patterned on the LTCC. All millimeter-wave components are contained within the module and the only interfaces to the module are the IF and bias lines. Transmit power of the module is +\11.6-dBm effective isotropic radiated power with an IF bandwidth of 400 MHz. The LTCC module measures \ 13\times \ 24~\ mm^2 and has a dc power consumption of 130 mW. Reception of a 20-MHz square wave from a tag 5 cm apart from the reader is demonstrated; the suggested millimeter-wave identification concept enables a \10^2–\10^3-fold data-rate increase in comparison to the present near-field communication technique, with similar size, range, and power consumption of the reader. [ABSTRACT FROM AUTHOR]

The relatively high dielectric constant of the low-temperature cofired ceramic (LTCC) substrate materials can reduce the antenna gain and increase the mutual coupling in antenna arrays due to the increased surface-wave power. We present a design of a uniplanar-compact electromagnetic band-gap (UC-EBG) structure on the Ferro A6-S LTCC tape system operating in the 60-GHz frequency band. The UC-EBG design is used with an aperture-coupled microstrip-line-fed patch antenna (ACMPA) and with a 16-element array to increase the antenna gain. The UC-EBG is also used to reduce the mutual coupling between antennas in the Eand H-planes. The performance of the antennas with and without UC-EBG are evaluated with the probe-station and radiation-pattern measurements. In addition, the reflection from the UC-EBG surface is measured using a WR-15 waveguide excitation. Good agreement is achieved between the simulations and the measurements. An increase of up to 4.5 and 2.3 dBi is achieved in the gain for a single element and for a 16-element array, respectively. A reduction of up to 11.8 dB is observed in the E-plane coupling between two patches. The presented design is suitable for electromagnetic shielding, reduction of coupling in integrated LTCC modules, and providing high gain antennas for low-cost millimeter-wave applications. [ABSTRACT FROM AUTHOR]

Pompe disease is a rare, progressive disease leading to skeletal muscle weakness due to deficiency of the acid α-glucosidase (GAA) enzyme. Herein we report the first diagnosed Finnish patient with a phenotype compatible with the late-onset form of Pompe disease. Molecular genetic analysis of the GAA gene revealed a novel missense mutation, 1725C>A (Y575X), combined with a previously reported mutation, 1634C>T (P545L). Human recombinant α-glucosidase enzyme (alglucosidase-α) treatment was initiated for this patient at age 20 years. After 12 months she was no longer fully wheelchair-bound, and muscle strength had improved. No disease progression was visible on muscle magnetic resonance imaging of the lower limbs, and the energy state of the muscle cells increased by 46% on phosphorus magnetic resonance spectroscopy. Overall, our findings suggest that enzyme replacement therapy is indicated, even in patients with late-onset Pompe disease, to halt disease progression and improve the quality of daily life. Muscle Nerve, 2009 [ABSTRACT FROM AUTHOR]

The aim of this study was to characterize the magnetic resonance imaging (MRI) findings in chronic solvent encephalopathy (CSE) patients and to study whether the findings are associated with solvent exposure indices. The brain MRI scans of 71 CSE patients were independently re-evaluated and rated by two experienced neuroradiologists. All the work tasks were analyzed and the chemical composition of lifetime exposure was categorized. The MRI scans of 27/71 CSE patients (38%) were classified as abnormal. Brain atrophy in any brain area was found in 17/71 CSE patients (24%). Abnormal white matter hyperintensities (WMH) were found in 20/71 CSE patients (28%). Cerebral and cerebellar brain atrophy was associated with the duration of exposure in years, and vermian atrophy was associated with alcohol consumption. Periventricular and brainstem WMH were related to age. Slight brain atrophy is associated with CSE and there is a correlation between brain atrophy and the duration of exposure in years. However, all the MRI findings in CSE are non-specific and thus MRI is useful mainly in the differential diagnosis of CSE. [ABSTRACT FROM AUTHOR]

Abstract-The design is presented of aperture-coupled microstrip line-fed patch antennas (ACMPAs) and 4 × 4 planar arrays on Ferro A6-S low-temperature cofired ceramic (LTCC) substrate operating in the 60-GHz frequency band. In addition to the traditional ACMPA design, air cavities processed inside the LTCC substrate are used to improve the bandwidth and gain of the antennas. The arrays are excited through the microstrip-line feed networks using quarter-wave matched T-junctions and using Wilkinson power dividers. The results show that ACMPAs and arrays can be fabricated with a standard LTCC process even for the millimeter-wave region. Good agreement is achieved between simulations and measurements. The measured S-parameters indicate impedance bandwidths of 9.5% and 5.8% for the array elements with and without an. embedded cavity. The measured maximum gains for the 16-element patch arrays (with and without cavity) are 18.2 and 15.7 dBi, respectively. [ABSTRACT FROM AUTHOR]

Hereditary gelsolin amyloidosis (AGel amyloidosis) is a systemic disorder caused by a G654A or G654T gelsolin mutation, reported from Europe, North America, and Japan. Principal clinical signs are corneal lattice dystrophy, cutis laxa and cranial neuropathy, often deleterious at advanced age. Peripheral neuropathy, if present, is usually mild. We report a 78-year-old male Finnish patient who presented with ataxia and mainly sensory peripheral polyneuropathy (PNP) signs, causing severe disability and ambulation loss. Electrophysiological studies showed severe generalized chronic mainly axonal sensorimotor PNP with facial paralysis. In magnetic resonance imaging proximal lower limb and axial muscle atrophy with fatty degeneration as well as moderate spinal cord atrophy were seen. A G654A gelsolin mutation was demonstrated but no other possible causes of his disability were found. At age 79 years he became bedridden and died of pulmonary embolism. Neuropathological examination revealed marked gelsolin amyloid deposition at vascular and connective tissue sites along the entire length of the peripheral nerves extending to the spinal nerve roots, associated with severe degeneration of nerve fibers and posterior columns. Our report shows that advanced AGel amyloidosis due to degeneration of central and distal sensory nerve projections results in deleterious ataxia with fatal outcome. Severe posterior column atrophy may reflect radicular AGel deposition, although even altered gelsolin-actin interactions in neural cells possibly contribute to neurodegeneration with successive ataxia in carriers of a G654A gelsolin mutation. [ABSTRACT FROM AUTHOR]

Background: Muscle pathology of the arm and forearm in brachial plexus birth injury (BPBI) with elbow flexion contracture has not been evaluated with MRI.Objective: To determine whether limited range of motion of the elbow in BPBI is correlated with specific patterns of muscular pathology.Materials and Methods: For 15 BPBI patients, total active motion (TAM) of the elbow (extension-flexion) and the forearm (pronation-supination) were measured. MRI of the elbow joints and musculature allowed assessment of elbow congruency. Fatty infiltration and size reduction of the muscles were graded semiquantitatively.Results: Mean TAM of the elbow was 113 degrees (50 degrees-140 degrees) and that of the forearm 91 degrees (10 degrees-165 degrees). The greater the size reduction of the brachioradialis muscle, the more diminished was elbow TAM. The more extensive the BPBI and muscle pathology of the pronator teres muscle, the more limited was the TAM of the forearm. Pathology of the supinator and brachialis muscles was evident in every patient.Conclusion: Extensive BPBI may result in marked limitation of TAM. Elbow flexion contracture seems to be caused mainly by brachialis muscle pathology. Prosupination of the forearm is better preserved when the pronator teres is not severely affected. MRI can reliably show the extent of muscle pathology in BPBI. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate rotator cuff muscles and the glenohumeral (GH) joint in brachial plexus birth injury (BPBI) using MRI and to determine whether any correlation exists between muscular abnormality and the development of glenoid dysplasia and GH joint incongruity.Materials and Methods: Thirty-nine consecutive BPBI patients with internal rotation contracture or absent active external rotation of the shoulder joint were examined clinically and imaged with MRI. In the physical examination, passive external rotation was measured to evaluate internal rotation contracture. Both shoulders were imaged and the glenoscapular angle, percentage of humeral head anterior to the middle of the glenoid fossa (PHHA) and the greatest thickness of the subscapular, infraspinous and supraspinous muscles were measured. The muscle ratio between the affected side and the normal side was calculated to exclude age variation in the assessment of muscle atrophy.Results: All muscles of the rotator cuff were atrophic, with the subscapular and infraspinous muscles being most severely affected. A correlation was found between the percentage of humeral head anterior to the middle of the glenoid fossa (PHHA) and the extent of subscapular muscle atrophy (r(s)=0.45, P=0.01), as well as between its ratio (r(s)=0.5, P P=0.01). Severity of rotator cuff muscle atrophy correlated with increased glenoid retroversion and the degree of internal rotation contracture.Conclusions: Glenoid retroversion and subluxation of the humeral head are common in patients with BPBI. All rotator cuff muscles are atrophic, especially the subscapular muscle. Muscle atrophy due to neurogenic damage apparently results in an imbalance of the shoulder muscles and progressive retroversion and subluxation of the GH joint, which in turn lead to internal rotation contracture and deformation of the joint. [ABSTRACT FROM AUTHOR]

Eleven hips in nine patients with Perthes' disease were studied by plain radiography at 3-month and MRI at 6-month intervals over a period of 2 years. The aim was to clarify the value of MRI in estimating epiphyseal involvement and in predicting uncoverage of the epiphysis. Signal intensities of the epiphysis and metaphysis were visually evaluated from T1- (T1W) and T2-weighted (T2W) images. The extent of decreased signal intensity (DSI) in the epiphyses was volumetrically calculated from T1W images and then compared with follow-up radiographs. The area of epiphyseal DSI corresponding best with Catterall's classification was seen by MRI 3–8 months after the first symptoms. MRI images obtained earlier usually showed less involvement than the follow-up radiographs. However, two features predicting extensive epiphyseal necrosis were: (1) DSI on both T1W and T2W images covering over two-thirds of the epiphysis and (2) diffuse bone marrow oedema of the femoral neck and metaphysis. When T1W images showed a reappearance of high signal intensity patches in the lateral quarter of the epiphysis, no clinically significant uncoverage was seen during the follow-up. Extensive epiphyseal necrosis can, therefore, sometimes be predicted by MRI even within the first 3 months, but MRI visualises epiphyseal involvement more clearly 3–8 months after the first symptoms. [ABSTRACT FROM AUTHOR]

Objective: To compare indium In 111 altumomab pentetate–labeled antimyosin scintigraphy with magnetic resonance imaging (MRI) in the diagnosis and follow-up of patients with myositis. Design and Methods: Sixteen patients with polymyositis and 1 patient with dermatomyositis, all verified with biopsy samples, were examined during diagnostic evaluation with antimyosin antibody scintigraphy and low-field MRI of the thighs and calves using T[sub 1]- and T[sub 2]-weighted sequences. Both examinations were repeated 6 to 22 months after therapeutic intervention with anti-inflammatory drugs. The performance of the 2 methods for the assessment of the severity of muscle inflammation was evaluated using comparison with clinical examination and the serum creatine kinase level. Results: At diagnosis all patients had increased uptake of antimyosin antibody in the thighs and/or calves. In T[sub 2]-weighted MRI images, increased signal intensity changes reflecting intramuscular edema and inflammation were seen in all patients in at least 1 muscle group in the thighs or calves. After anti-inflammatory drug therapy, the mean uptake of antibody and the mean signal intensity changes in T[sub 2]-weighted MRI had decreased. However, in T[sub 1]-weighted MRI the signal intensity changes reflecting intramuscular fatty degeneration were more pronounced in the follow-up study. The level of serum creatine kinase had decreased markedly by the second examination except in 1 patient who also had more accumulation of antibody in the calves after than before treatment. The clinical condition improved in 8 patients and remained unchanged in 9 patients. Conclusions: Antimyosin scintigraphy and T[sub 2]-weighted MRI are feasible tools for the detection and follow-up of lesions in patients with myositis. Scintigraphy findings correlate with serum creatine kinase activity and seem to reflect disease activity better than T[sub 2]-weighted MRI changes, whereas secondary degenerative intra... [ABSTRACT FROM AUTHOR]

The radiologic imaging of esophageal cysts (EC) in adults is described. These rare cysts, often detected incidentally on routine chest radiographs, seldom produce symptoms, but they may cause precordial sensations, arrhythmias, and dysphagia. They may also bleed and become malignant. As surgical excision is the treatment of choice, the preoperative diagnosis must be exact. For this, magnetic resonance imaging (MRI) or endoscopic ultrasound seem to be the imaging methods of choice even if a plausible diagnosis can be advanced on computed tomography (CT). Chest x-ray or esophagus roentgenogram have little differential diagnostic value. [ABSTRACT FROM AUTHOR]

Since the introduction of bolometers more than a century ago, they have been used in various applications ranging from chemical sensors, consumer electronics, and security to particle physics and astronomy. However, faster bolometers with lower noise are of great interest from the fundamental point of view and to find new use-cases for this versatile concept. We demonstrate a nanobolometer that exhibits roughly an order of magnitude lower noise equivalent power, 20 zW ∕ Hz , than previously reported for any bolometer. Importantly, it is more than an order of magnitude faster than other low-noise bolometers, with a time constant of 30 μs at 60 zW ∕ Hz . These results suggest a calorimetric energy resolution of 0.3 zJ = h × 0.4 THz with a time constant of 30 μs. Further development of this nanobolometer may render it a promising candidate for future applications requiring extremely low noise and high speed such as those in quantum technology and terahertz photon counting. Bolometers have been used for over a century for a wide range of applications with recent developments aiming at reducing noise and increasing readout speed. The authors present a nanobolometer with an order of magnitude lower noise and over an order of magnitude increased readout speed than previously shown, making this instrument a promising candidate for applications in quantum and terahertz technology. [ABSTRACT FROM AUTHOR]

Hereditary gelsolin amyloidosis (AGel amyloidosis) is a systemic disorder caused by a G654A or G654T gelsolin mutation, reported from Europe, North America, and Japan. Principal clinical signs are corneal lattice dystrophy, cutis laxa and cranial neuropathy, often deleterious at advanced age. Peripheral neuropathy, if present, is usually mild. We report a 78- year old male Finnish patient who presented with ataxia and mainly sensory peripheral polyneuropathy (PNP) signs, causing severe disability and ambulation loss. Electrophysiological studies showed severe generalized chronic mainly axonal sensorimotor PNP with facial paralysis. In magnetic resonance imaging proximal lower limb and axial muscle atrophy with fatty degeneration as well as moderate spinal cord atrophy were seen. A G654A gelsolin mutation was demonstrated but no other possible causes of his disability were found. At age 79 he became bedridden and died of pulmonary embolism. Neuropathological examination revealed marked gelsolin amyloid deposition at vascular and connective tissue sites along the entire length of the peripheral nerves extending to the spinal nerve roots, associated with severe degeneration of nerve fibers and posterior columns. Our report shows that advanced AGel amyloidosis due to degeneration of central and distal sensory nerve projections results in deleterious ataxia with fatal outcome. Severe posterior column atrophy may reflect radicular AGel deposition, although even altered gelsolin – actin interactions in neural cells possibly contribute to neurodegeneration with successive ataxia in carriers of a G654A gelsolin mutation. [ABSTRACT FROM AUTHOR]