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A microelectromechanical systems analog tunable capacitor has been designed and fabricated for implementation into a two-pole UHF filter. Recent developments on the capacitor have improved the RF device performance significantly, and have resulted in improved UHF filter performance. In the 225-400-MHz range that this device is intended for, Q values are in excess of 100. In addition, an 8.4:1 tuning ratio has been achieved with continuous tuning over a 1.4: 11.9-pF range. When implemented into a two-pole UHF filter, tuning over the entire 225-400-MHz range was achieved with a loss under 6.2 dB. Index Terms--Reliability, RF microelectromechanical systems (MEMS), tunable capacitors, tunable filters.

The focus of this research was to design a functional and user-friendly reacher for people with spinal cord injuries (SCIs). Engineering advancements have taken assistive robotics to new dimensions. Technologies such as wheelchair robotics and myo-electronically controlled systems have opened up a wide range of new applications to assist people with physical disabilities. Similarly, exo-skeletal limbs and body suits have provided new foundations from which technologies can aid function. Unfortunately, these devices have issues of usability, weight, and discomfort with donning. The Smart Assistive Reacher Arm (SARA) system, developed in this research, is a voice-activated, lightweight, mobile device that can be used when needed. SARA was built to help overcome daily reach challenges faced by individuals with limited arm and hand movement capability, such as people with cervical level 5-6 (C5-6) SCI. This article shows that a functional reacher arm with voice control can be beneficial for this population. Comparison study with healthy participants and an SCI participant shows that, when using SARA, a person with SCI can perform simple reach and grasp tasks independently, without someone else’s help. This suggests that the interface is intuitive and can be easily used to a high level of proficiency by a SCI individual. [ABSTRACT FROM PUBLISHER]

The emergence of interconnected networks which include an intelligent lighting infrastructure is creating urban spaces possessing ambient intelligence in the form of smart sensors, embedded microprocessors, and cybernetic feedback systems. In his paper, Architectural Relevance of Cybernetics (1969), Gordon Pask envisioned an adaptive cybernetic system wherein the architecture becomes an electronic interface. Pask's approach has powerful implications for the universal design of “smart” urban infrastructures. New intelligent infrastructure systems are described within the context of interconnected cybernetic networks to consider the universal design of more equitable, sustainable, and secure urban space. [ABSTRACT FROM AUTHOR]

ABSTRACT An analytic statistical model is presented for aggregate ground-based continuous interference to airborne Global Positioning Systems receivers employed in the U.S. Air Traffic System. The model computes total interference from a random number of uniformly distributed ground based emitters utilizing statistical path loss models to account for the propagation environment in the vicinity of metropolitan airports. Numerical results are computed at the GPS L1 center frequency (1575.42 MHz) for the mean and standard deviation of the aggregate interference power density as well the associated probability distribution function. Comparisons are made between results from the new model and prior interference analysis studies. Copyright © 2012 Institute of Navigation. [ABSTRACT FROM AUTHOR]

Summary: Hepatic amyloid deposition in the form of globular inclusions is a rare occurrence. Only 24 such cases have been reported to date. Its clinical and pathological significance are undefined. Unawareness of such a pattern can cause diagnostic confusion. We herein describe a case of globular hepatic amyloid in a patient with a B-cell lymphoma and chronic hepatitis C. The findings in our case support the literature data in that (1) it is often an incidental finding during workup for other coexisting conditions and (2) its morphology is peculiar but can be recognized with ease if one is aware of its existence. Our case also provides new insights into this condition. First, it represents the first nonautopsy case to demonstrate that globular hepatic amyloid is an indication of systemic amyloidosis, thus emphasizing the clinical importance of the recognition of this condition. Second, in our case, there was a coexisting B-cell lymphoma, the constituent cells of which showed immunoglobulin λ light chain restriction, and patient''s serum λ light chain was elevated. However, light chain restriction was not demonstrated in the globular inclusions, and there was no evidence of monoclonal gammopathy by serum electrophoresis. Whether immunoglobulin light-chain abnormality played a causal role in this condition is to be determined. [Copyright &y& Elsevier]

The term malignant fibrous histiocytoma was coined by Stout and associates in the 1960s to encompass pleomorphic soft tissue sarcomas presumably derived from histiocytes that are capable of fibroblastic transformation. The concept was reaffirmed in the following 2 decades and malignant fibrous histiocytoma thus was regarded as the most common soft tissue tumor in older adults. However, recent more critical clinicopathologic, ultrastructural, and immunohistochemical studies have shown that malignant fibrous histiocytomas are not derived from histiocytic "facultative fibroblasts" and many neoplasms so diagnosed actually are pleomorphic subtypes of other sarcomas. Meticulous electron microscopic and immunohistochemical investigations also found that the more common storiform-pleomorphic, myxoid, and perhaps the giant cell subtypes are composed of variable mixtures of fibroblasts and phenotypically modulated fibroblastic cells, notably myofibroblasts and histiofibroblasts. On the basis of these findings, we propose a new classification for the above subtypes of so called malignant fibrous histiocytoma, the majority of which are variants of pleomorphic fibrosarcoma. [ABSTRACT FROM AUTHOR]

Lymphohistiocytoid mesothelioma(LHM)is a term proposed to designate a variant of mesothelioma that assumes a histiocytoid morphology and contains intense lymphocytic infiltrates. Reports on this variant are few, and its clinicopathologic and ultrastructural characteristics are still to be defined. The authors have studied 4 such cases that were identified among 120 mesotheliomas in the electron microscopy(EM)files of a single institution between 1982 and 2002. Histologically, all 4 lesions were composed of diffuse proliferations of cells with a histiocytoid appearance, admixed with an intense lymphocytic infiltrate. All 4 were associated with an unequivocal sarcomatoid component. Immunohistochemical(IHC)studies showed that the majority of histiocytoid cells were positive for CD68 and vimentin in all 4 cases, suggesting fibrohistiocytic differentiation. Immunoreactivity for calretinin and AE1:AE3 was only very focally identified in 3 of 4 cases. All cases were negative for CEA(M), Leu-M1, and B72.3. The lymphocytic component in all 4 cases was almost entirely composed of CD3- and CD8-positive, small, mature T cells, with only a minor component of CD20-positive cells and occasional eosinophils. Although all cases contained numerous CD68 positive atypical cells, co-expression of CD68 and either calretinin or keratin by individual cells was difficult to demonstrate by immunohistochemistry. Ultrastructurally, 3 of the 4 cases demonstrated very focal mesothelial differentiation as evidenced by long and slender surface microvilli, including the case with negative immunoreactivity for calretinin and cytokeratin. Review of the literature yielded 6 additional LHM cases. Analysis of all 10 cases showed a male predominance(8:2)with a mean age of 58 years(31–73 years). All 10 cases involved the pleura. Three of 10 patients had known asbestos exposure. Six of 10 patients died of disease at 2–20 months after the diagnosis(mean, 6.9 months). The findings suggest that LHM is a distinct morphological variant of sarcomatoid mesothelioma for which mesothelial differentiation is difficult to document. Many of the cells composing these tumors exhibit fibrohistiocytic differentiation. The unusual morphological pattern of LHM makes a combined modality approach, including IHC, EM, and a knowledge of the clinical/radiologic findings, essential in achieving a correct diagnosis. [ABSTRACT FROM AUTHOR]

Since 1980 when Sibley and coworkers first described a nodal neoplasm of unknown histogenesis with striking surface microvilli for which they introduced the term "anemone cell," a series of reports have appeared in the literature illustrating tumors with similar ultrastructural features. While most reported cases showed differentiation along a particular line, rare cases remained histogenetically unclear. In this report a case is described of epithelioid gastric gastrointestinal stromal tumor metastatic to the liver, showing conspicuous long microvillus-type cell processes partially or circumferentially coating the cell surfaces, thus qualifying as yet another tumor type with anemone cell features. [ABSTRACT FROM AUTHOR]

Deciduoid mesothelioma was first described in young females and in the peritoneum, which led to the suggestion that deciduoid mesothelioma was a distinct subtype with specific clinical and pathologic features. Later reports, however, have shown that this type of mesothelioma may also occur in elderly people and in the pleura. Cases reported in the literature so far are limited, and the disease is not well defined. The authors report the histologic, immunohistochemical, ultrastructural, and clinical findings of 5 cases of deciduoid mesothelioma, and review the literature reports. The results demonstrate that the presence of numerous cytoplasmic intermediate filaments, either dispersed or bundled, appear to be the likely ultrastructural basis for the deciduoid histologic appearance. Twenty-one cases of deciduoid mesothelioma were identified in the literature. Analyses of these 21 cases and the authors' 5 cases showed an age range of 13-78 years (median 53 years) and a slight female predominance (female to male ratio of 1.4:1). Fourteen of 26 cases (54%) occurred in the peritoneum. Seven of 20 patients (35%) had a documented history of asbestos exposure. Fifteen of 20 patients died, with a mean survival time of 7.33 months (range 1-21 months). Five of 20 patients were alive at a follow-up time of 8 months to 5 years. These findings suggest that the so-called deciduoid mesothelioma has some clinical and pathologic features that are dissimilar to mesothelioma in general. Whether it truly represents a pathogenetically distinct variant or merely an expansion of the morphologic spectrum awaits further studies. [ABSTRACT FROM AUTHOR]

Because the fibroblast has a remarkable capability of phenotypic modulations, reflected in both morphologic and immunohistochemical (IHC) changes, ultrastructural studiesare mandatory to identify the variants of fibroblasts. Myofibroblasts or histiofibroblasts are such examples, demonstrating chimeric ultrastructural features of fibroblastic cells in common with smooth muscle cells or with histiocytes, respectively. The presence of epithelioid fibroblastic cells sharing morphologic features with epithelial or plasma cells has not been yet characterized. The authors identified 4 cases of fibrosarcomas (FS) characterized by an unusual phenotype and associated with peculiar ultrastructural findings. The electron microscopic (EM) findings were correlated with the histologic appearance and immunoprofile. All tumors were located in the extremities, 3 in soft tissues and 1 in the bone. By light microscopy 2 cases were composed predominantly by round uniform cells with a striking plasmacytoid appearance. One case mimicked carcinoma, composed predominantly by epithelioid cells and scattered giant tumor cells. The fourth case showed a mixture of plasmacytoid-like and epithelioid cells. By IHC, tumor cells were positive for vimentin and in 2 cases also for epithelial membrane antigen. Kappa/lambda light chain and cytokeratins markers were negative. By EM all 4 tumors showed in addition to classic features of fibroblasts, unusual epithelial-type features, such as secretory granules of "neurosecretory-type" (3 cases), rudimentary cell junctions (3 cases), microvilli (2 cases), and lumen-like structures (1 case). One plasmacytoid-type tumor showed finely granular extracellular deposits. The study describe 4 examples of fibrosarcomas with unusual features at the ultrastructural level, which are associated microscopically with a peculiar phenotype, mimicking plasmacytoma or carcinoma. These findings broaden the spectrum of fibroblastic cell variants in neoplasia. [ABSTRACT FROM AUTHOR]

Examines the numerous small vesicles in clear cell leiomyoma of deep soft tissue. Derivation of the identifying feature of the tumor cells; Presence of clear cell leiomyoma around skeletal muscle fibers; Composition of the clear cells.

Recovery from anoxia has been evaluated in the isovolumic non-recirculating paced perfused rat heart. Seventy studies were performed consisting of 15 min of aerobic perfusion (AP); AP+15 min anoxic perfusion; and AP+15 min anoxic perfusion+15 min reoxygenation (recovery). Krebs-Ringer-bicarbonate+5 mmol glucose (KRB) (290 mmol) was compared to KRB+mannitol (350 mmol). Mannitol decreased myocardial water content. It improved recovery of haemodynamic function after reoxygenation. With KRB alone left ventricular systolic peak pressure (LVSP) decreased 32% and maximum dP/dt by 50%. With mannitol added LVSP decreased 18% and dP/dt 21% (<0·01). KRB and mannitol did not differentially affect total coronary flow, lactate and glucose extraction, tissue glycogen, creatine phosphate or adenine nucleotide concentrations. No difference in submicroscopic appearance was noted with either perfusate during aerobic perfusion. Anoxic hearts perfused with isosmolal KRB demonstrated the most severe ultrastructural alterations including mitochondrial swelling with disruption of cristae and extraction of matrix components, myofibrillar fusion and contraction bands, and subsarcolemmal oedema and vacuolization. These changes were only partially reversed during reoxygenated perfusion. However, cellular changes were reversed or markedly improved during both the anoxic and reoxygenation perfusion periods with hyperosmolal solutions. When studied by silicone rubber injection of the microcirculation, only focal capillary endothelial cell swelling was noted and no difference in arteriolar or capillary filling was observed with either perfusate. Mannitol appears to improve LV function by direct myocardial osmotic action unrelated to enhanced energy production. [ABSTRACT FROM PUBLISHER]