Application of analysis techniques for low frequency interior noise and vibration of commercial aircraft

Finite element analysis (FEA), statistical energy analysis (SEA), and a power flow method (computer program PAIN) were used to assess low frequency interior noise associated with advanced propeller installations. FEA and SEA models were used to predict cabin noise and vibration and evaluate suppression concepts for structure-borne noise associated with the shaft rotational frequency and harmonics (less than 100 Hz). SEA and PAIN models were used to predict cabin noise and vibration and evaluate suppression concepts for airborne noise associated with engine radiated propeller tones. Both aft-mounted and wing-mounted propeller configurations were evaluated. Ground vibration test data from a 727 airplane modified to accept a propeller engine were used to compare with predictions for the aft-mounted propeller. Similar data from the 767 airplane was used for the wing-mounted comparisons

Nichtdermatomgebundene somatosensorische Defizite bei chronischen Schmerzpatienten

Zusammenfassung: Nichtdermatomgebundene somatosensorische Defizite (NDSD) sind bei chronischen Schmerzpatienten häufig und weisen auf Schmerzsensibilisierung und Schmerzzentralisierung hin. Klinisch findet sich in der Regel eine Berührungs- und Thermhypästhesie mit oftmals quadrantenartiger oder halbseitiger Ausbreitung. Bei der Mehrzahl der Patienten liegt anamnestisch ein somatisch-nozizeptives Auslöseereignis vor, das aber wie das komplexe regionale Schmerzsyndrom (CRPS) in keiner eindeutigen Relation zur nachfolgenden Schmerzstörung steht. Wie bei vielen chronischen Schmerzstörungen weisen auch Patienten mit NDSD oft eine überdurchschnittliche psychobiografische Stressbelastung auf. Die Ergebnisse der funktionellen Bildgebung weisen auf ein komplexes Muster zentralnervöser Dysregulationen hi

The value of different resistance parameters in distinguishing biopsy-proved dysfunction of renal allografts

The data concerning the value of duplex sonography in diagnosing parenchymatous renal allograft dysfunction are controversial. Most early studies did not take into consideration the many factors influencing resistance parameters. We therefore performed a prospective, biopsy-controlled study with exclusion of all known sources of error regarding resistance parameters. Furthermore we investigated the value of a new resistance parameter, the systolic deceleration percentage. Forty-seven duplex sonographic studies were performed on 43 patients (30 male, 13 female, median age 47 years, range 7-70). Fourteen studies were done on normally functioning grafts (control group) an average of 33 days after transplantation. Thirty-three studies were performed on dysfunctional grafts immediately prior to biopsy. Grafts which had been transplanted more than a year previously or with vascular findings or any other clinical or sonographic pathology probably explaining function deterioration were excluded. In all patients, the resistive index (RI), pulsatility index (PI) and systolic deceleration percentage (DP) were calculated in the main renal artery and in the interlobar artery. Of the 33 grafts with dysfunction, nine had vascular rejection (VR), 11 interstitial rejection (IR), 11 cyclosporin A toxicity (CAT) and two other histologies (OR). The mean RI in normal grafts (NO) was 0.71±0.06 in the main artery and 0.68±0.06 in the interlobar artery, in VR 0.86±0.12 and 0.80±0.18, in IR 0.72±0.05 and 0.70±0.07, in CAT 0.67±0.06 and 0.65±0.07 and in OR 0.64±0.07 and 0.60±0.01. For PI, the values were 1.45±0.23 and 1.41±0.28 (NO), 3.5±2.13 and 2.92±2.16 (VR), 1.55±0.26 and 1.46±0.33 (IR), 1.32±0.25 and 1.27±0.26 (CAT) and 1.30±0.34 and 1.13±0.04 (OR). For DP we calculated 28±5% and 29±6% (NO), 43±14% and 36±6% (VR), 29±9% and 27±9% (IR), 31±8% and 32±7% (CAT ) and 32±4% and 28±3% (OR). The sensitivity/specificity for VR with a cutoff mean+2 SD was 0.44/1 for RI, 0.55/0.97 for PI and 0.33/0.89 for DP. It was concluded that:(1) despite the high selection of our patient group, diagnostic accuracy of duplex sonography for diagnosing parenchymatous function disorder in renal allograft remains insufficient; (2) in vascular rejection only, the resistance parameters differ significantly from the values of normal allografts; (3) the higher the cutoff of resistance parameters, the better the specificity and the worse the sensitivity for diagnosing vascular rejection; (4) of all investigated resistance parameters, the RI is the most practical due to a simple measurement techniqu

Early renal transplant dysfunction due to arterial kinking stenosis

The main differential diagnoses of early renal trans-plant dysfunction include ischaemic damage, cyclospo-rin toxicity, and rejection [1]. Rarer causes include bleeding, ureteral obstruction, urinary leak, venou

Induction of apoptosis in host cells: a survival mechanism for Leishmania parasites?

Leishmania parasites invade host macrophages, causing infections that are either limited to skin or spread to internal organs. In this study, 3 species causing cutaneous leishmaniasis, L. major, L. aethiopica and L. tropica, were tested for their ability to interfere with apoptosis in host macrophages in 2 different lines of human monocyte-derived macrophages (cell lines THP-1 and U937) and the results confirmed in peripheral blood mononuclear cells (PBMC). All 3 species induced early apoptosis 48 h after infection (expression of phosphatidyl serine on the outer membrane). There were significant increases in the percentage of apoptotic cells both for U937 and PBMC following infection with each of the 3 species. Early apoptotic events were confirmed by mitochondrial membrane permeabilization detection and caspase activation 48 and 72 h after infection. Moreover, the percentage of infected THP-1 and U937 macrophages increased significantly (up to 100%) following treatment with an apoptosis inducer. Since phosphatidyl serine externalization on apoptosing cells acts as a signal for engulfment by macrophages, induction of apoptosis in the parasitized cells could actively participate in spreading the infection. In summary, parasite-containing apoptotic bodies with intact membranes could be released and phagocytosed by uninfected macrophages

Nichtdermatomgebundene somatosensorische Defizite bei chronischen Schmerzpatienten

Nondermatomal somatosensory deficits (NDSDs) are frequently found in chronic pain patients and allude to pain sensitization and pain centralization. In the clinical examination NDSDs are as a rule accompanied by hyposensitivity to touch and heat perception often with a quadrantal or hemibody distribution. The majority of NDSD patients show a trigger episode with a somatic nociceptive trauma in the case history. These somatic findings, however, never fully explain the pain disorder, analogue to the complex regional pain syndrome (CRPS). Most patients with chronic pain disorders as well as those with NDSD often report an antecedent period of high psychobiological stress. The data from functional imaging reveal a complex pattern of a central nervous dysregulation

Consistent Atomic Geometries and Electronic Structure of Five Phases of Potassium Niobate from Density-Functional Theory

We perform a comprehensive theoretical study of the structural and electronic properties of potassium niobate (KNbO3) in the cubic, tetragonal, orthorhombic, monoclinic, and rhombohedral phase, based on density-functional theory. The influence of different parametrizations of the exchange-correlation functional on the investigated properties is analyzed in detail, and the results are compared to available experimental data. We argue that the PBEsol and AM05 generalized gradient approximations as well as the RTPSS meta-generalized gradient approximation yield consistently accurate structural data for both the external and internal degrees of freedom and are overall superior to the local-density approximation or other conventional generalized gradient approximations for the structural characterization of KNbO3. Band-structure calculations using a HSE-type hybrid functional further indicate significant near degeneracies of band-edge states in all phases which are expected to be relevant for the optical response of the material

fMRI evidence of ‘mirror’ responses to geometric shapes

Mirror neurons may be a genetic adaptation for social interaction [1]. Alternatively, the associative hypothesis [2], [3] proposes that the development of mirror neurons is driven by sensorimotor learning, and that, given suitable experience, mirror neurons will respond to any stimulus. This hypothesis was tested using fMRI adaptation to index populations of cells with mirror properties. After sensorimotor training, where geometric shapes were paired with hand actions, BOLD response was measured while human participants experienced runs of events in which shape observation alternated with action execution or observation. Adaptation from shapes to action execution, and critically, observation, occurred in ventral premotor cortex (PMv) and inferior parietal lobule (IPL). Adaptation from shapes to execution indicates that neuronal populations responding to the shapes had motor properties, while adaptation to observation demonstrates that these populations had mirror properties. These results indicate that sensorimotor training induced populations of cells with mirror properties in PMv and IPL to respond to the observation of arbitrary shapes. They suggest that the mirror system has not been shaped by evolution to respond in a mirror fashion to biological actions; instead, its development is mediated by stimulus-general processes of learning within a system adapted for visuomotor control

Anti-filarial Activity of Antibiotic Therapy Is Due to Extensive Apoptosis after Wolbachia Depletion from Filarial Nematodes

Filarial nematodes maintain a mutualistic relationship with the endosymbiont Wolbachia. Depletion of Wolbachia produces profound defects in nematode development, fertility and viability and thus has great promise as a novel approach for treating filarial diseases. However, little is known concerning the basis for this mutualistic relationship. Here we demonstrate using whole mount confocal microscopy that an immediate response to Wolbachia depletion is extensive apoptosis in the adult germline, and in the somatic cells of the embryos, microfilariae and fourth-stage larvae (L4). Surprisingly, apoptosis occurs in the majority of embryonic cells that had not been infected prior to antibiotic treatment. In addition, no apoptosis occurs in the hypodermal chords, which are populated with large numbers of Wolbachia, although disruption of the hypodermal cytoskeleton occurs following their depletion. Thus, the induction of apoptosis upon Wolbachia depletion is non-cell autonomous and suggests the involvement of factors originating from Wolbachia in the hypodermal chords. The pattern of apoptosis correlates closely with the nematode tissues and processes initially perturbed following depletion of Wolbachia, embryogenesis and long-term sterilization, which are sustained for several months until the premature death of the adult worms. Our observations provide a cellular mechanism to account for the sustained reductions in microfilarial loads and interruption of transmission that occurs prior to macrofilaricidal activity following antibiotic therapy of filarial nematodes