Transfer function of sound transmission in subglottal human respiratory system at low frequencies

The amplitude of sound transmission from the mouth to a site overlying the extrathoracic trachea and two sites on the posterior chest wall was measured in eight healthy adult male subjects at resting lung volume over the 100- to 600-Hz frequency range. The ratios of the estimated magnitude spectra of transmission of each of the chest wall sites to the tracheal site were determined, with the resulting spectra representing effective transfer functions of transmission in the subglottal system. For the group, the transfer functions exhibited a single peak, which occurred at 143 +/- 13 Hz (mean +/- SD) with a quality factor (Q) of 2.0 +/- 0.2 for the upper chest wall site and at 129 +/- 6 Hz with a Q of 2.2 +/- 0.4 for the lower site. The trend of decreasing spectral energy with increasing frequency was indicated by roll-offs of -10 +/- 4 and -17 +/- 5 dB/octave from 300 to 600 Hz at the two sites, respectively. The fundamental radial mode of a model thoracic cavity, which is a large rigid cylinder filled with lossless lung tissue, provides a good estimate of the observed low-frequency resonance. This agreement suggests that thoracic cavity resonances may have particularly important effects on sound transmission at frequencies below approximately 250 Hz, where the magnitude of parenchymal attenuation appears to be small.     

Nucleotides and Nucleotide Sugars in Developing Maize Endosperms (Synthesis of ADP-Glucose in brittle-1)

As part of an in vivo study of carbohydrate metabolism during development of Zea mays L. kernels, quantities of nucleotides and nucleotide sugars were measured in endosperm extracts from normal, the single-mutant genotypes shrunken-1 (sh1), shrunken-2 (sh2), and brittle-1 (btl}, and the multiple-mutant genotypes sh1bt1, sh2bt1, and sh1sh2bt1. Results showed that bt1 kernels accumulated more than 13 times as much adenosine 5[prime] diphospho-glucose (ADP-Glc) as normal kernels. Activity of starch synthase in bt1 endosperm was equal to that in endosperm extracts from normal kernels. Thus the ADP-Glc accumulation in bt1 endosperm cells was not due to a deficiency in starch synthase. ADP-Glc content in extracts of sh1bt1 endosperms was similar to that in bt1, but in extracts of the sh2bt1 mutant kernels ADP-Glc content was much reduced compared to bt1 (about 3 times higher than that in normal). Endosperm extracts from sh1sh2bt1, kernels that are deficient in both ADP-Glc pyrophosphorylase (AGPase) and sucrose synthase, had quantities of ADP-Glc much lower than in normal kernels. These results clearly indicate that AGPase is the predominant enzyme responsible for the in vivo synthesis of ADP-Glc in bt1 mutant kernels, but Suc synthase may also contribute to the synthesis of ADP-Glc in kernels deficient in AGPase.     

Elucidation of the mechanism of CryIIIA overproduction in a mutagenized strain of Bacillus thuringiensis var. tenebrionis

NB176 is a Bacillus thuringiensis mutant derived by λ-irradiation of NB125 Bacillus thuringiensis var. tenebrionis (Krieg). It exhibits two interesting phenotypes: (i) oligosporogeny and (ii) twofold to threefold overproduction of the CryIIIA protein. Southern profiles of the NB176 strain showed an additional copy(s) of the cryIIIA gene located on a 4 kb HindIII fragment, in addition to the expected cryIIIA gene on a 3 kb HindIII fragment. Each cryIIIA gene-bearing HindIII fragment was cloned from NB176. The restriction map of the 3 kb HindIII fragment was identical to that published by Donovan and coworkers. Sequencing of the 4 kb HindIII fragment showed no alterations in the promoter region of the cryIIIA gene but did show replacement of the region immediately following the cryIIIA open reading frame with a sequence encoding a transposase with 50% amino acid homology to that of Tn 1000. These findings suggest that the overproduction phenotype of NB176 results from extra copies of the cryIIIA gene produced from a transposition event(s) induced or stabilized by γ-irradiation. Integration of additional copies of the cryIIIA gene into the native 90MDa plasmid of the wild-type B. thuringiensis var. tenebrionis strain resulted in strains that made enormous crystals, many possessing greatly enhanced insecticidal activity.     

Rumen contents as a reservoir of enterohemorrhagic Escherichia coli

Abstract We investigatedthe role of the rumen fermentation as a barries to the foodborne pathogen, Escherichia coli O157:H7. Strains of E. coli , including several isolates of O157:H7, grew poorly in media which simulated the ruminal environment of a well-fed animal. Strains of E. coli O157:H7 did not display a superior tolerance to ruminal conditions which may facilitate their colonization of the bovine digestive tract. Unrestricted growth of E. coli was observed in rumen fluid collected from fasted cattle. Growth was inhibited by rumen fluid collected from well-fed animals. Well-fed animals appear less likely to become reservoirs for pathogenic E. coli . These results have implications for cattle slaughter practices and epidemiological studies of E. coli O157:H7.     

Piping plover chick ecology following landscape-level disturbance

Population declines of disturbance-dependent species due to suppression of natural disturbances are realized across ecosystems. The piping plover (Charadrius melodus; plover), a disturbance-dependent and conservation-reliant shorebird that nests on sandy beaches and barrier islands on the Atlantic Coast, was listed under the United States Endangered Species Act in 1986. In 2012, Hurricane Sandy landed on Fire and Westhampton islands, barrier island nesting sites for plovers in New York, USA. Hurricane Sandy was a natural disturbance in this system, creating abundant nesting habitat. The number of chicks produced by a pair, or a population, is a direct measure of reproductive output, and gaining a better understanding of productivity and chick behavior following large-scale habitat creation may improve plover habitat management and potentially species persistence. We evaluated the effects of landscape features on habitat selection, behavior, and survival of plover broods using logistic regression, generalized linear mixed effects models, and survival models. Plover broods selected flatter sites with less dense vegetation than available at random. Chick foraging rates were highest in moist substrates and were lower in areas of higher nesting plover density. Chick survival was greater for broods that hatched earlier in the breeding season and increased as chicks aged. Generally, providing access to sites with flatter, moist substrates will likely result in higher quality brood rearing habitat on the landscape. Ultimately, vegetation removal and habitat management may be needed to reduce plover nesting density and ensure sufficient habitat, which may in turn improve plover chick survival. Moreover, sustaining natural landscape disturbances such as those resulting from storms, and not taking actions to prevent hurricane-created overwash, will allow these landscape features to persist.     

Sultans of Spin: Syrian Sacred Music on the World Stage

This article examines how the performance of a variety of Islamic music in transnational cultural circuits helps to promote the idea of a style of sacred music within the category of world music. Taking as an example the performance of the mawlawiyya, or "Whirling Dervish," music and dance by a Syrian–based ensemble, I show how the idea of an authentic local Syrian sacred music tradition requires its performance globally. I use the concept of the "world stage" to examine how musical performance practices that are represented as authentic local traditions obtain both their authenticity and their local specificity through their staging in global contexts. I further explore how such musical styles as sacred and Sufi emerge as naturalized categories in world music discourse, and how processes of differentiation and commodification reconfigure both the "local" and "global." [Keywords: world music, globalization, style, Syria, Islam]     

Discriminative effects of morphine administered intracerabrally in the rat

Rats were trained in a two-choice discrete trial avoidance paradigm to discriminate between saline and 3.0 mg/kg of morphine administered S.C. The microinjection of 0.3–3.0 μg of morphine into the lateral ventricle produced discriminative effects equivalent to those of the systemic training dose as measured by responding on the morphine-appropriate choice lever. Discriminative effects equivalent to those of the morphine training dose were not consistently produced by administration of morphine into the periaqueductal gray, lateral septum or dorsomedial thalamus in doses as high as 10 μg. However, the discriminative effects of systematically administered morphine were blocked by 10–30 μg of naloxone administered intracerebrally at all of the brain sites tested. Thus, the primary site at which morphine acts to produce discriminative effects in the rat is central, although the specific brain areas mediating these effects remain unidentified. The actions of naloxone could be the result of diffusion of the drug into the ventricular system or into the systemic circulation.     

Exogenous C1q reconstitutes a secondary deficiency of C5-deficient AKR mouse macrophages for FcR-dependent cellular cytotoxicity and phagocytosis

Studies originally designed to assess the putative role of endogenous C5 in macrophage activation for antibody-dependent cellular cytotoxicity (ADCC) yielded unanticipated results. Resident and inflammatory peritoneal macrophages from C5-deficient AKR mice were found to have significantly lower capacity for FcR-dependent ADCC activation and phagocytosis of IgG-opsonized SRBC targets than did C5-competent C3HeB/FeJ (C3H) mice. Reconstitution of the ADCC response of AKR macrophages was accomplished initially with C5-sufficient C3H mouse serum, which suggested that endogenous C5 may be required for ADCC activation. However, further investigation largely eliminated C5 involvement in that a heat-labile component of C5-deficient AKR serum was shown to be active in the reconstitution of ADCC activation of AKR macrophages. Macrophages from AKR mice were found to have significantly lower levels of C1q mRNA synthesis, endogenous C1q levels, and C1q secretion than did C3H mouse macrophages as determined by Northern blot, Western blot, and presynthetic radiolabeling analysis, respectively. The addition of purified exogenous C1q to IgG-opsonized SRBC targets fully reconstituted ADCC activation for AKR inflammatory peritoneal macrophages to levels of normally FcR-responsive C3H macrophages. Similarly, exogenous C1q augmented FcR-dependent phagocytosis of AKR macrophages but had no effect on macrophages from responsive C3H mice. Our results indicate that AKR mice have a deficiency for FcR-dependent cellular cytotoxicity and phagocytosis that is related to their low potential for C1q synthesis and secretion rather than to their established genetic deficiency for C5 synthesis. We tentatively conclude that endogenous C1q is required as an accessory molecule for macrophage FcR-dependent effector functions and that C5 is not a prerequisite for ADCC activation.