Sound production in Pituophis melanoleucus (Serpentes: Colubridae) with the first description of a vocal cord in snakes

The pine, gopher, or bull snake (Pituophis melanoleucus) makes two different defensive sounds. Hisses are characterized by lack of frequency and amplitude modulation; bellows have a brief initial period of high-amplitude, broad-frequency sound followed by a longer period of lower-amplitude, constant-frequency sound. Both defensive sounds contain distinct harmonic elements. The modulation and harmonic nature of these sounds seems to be unique among snakes. The larynx of Pituophis is unusual in having an epiglottal keel, a dorsal expansion of the cricoid cartilage, previously proposed to contribute to sound production; however, this study shows that it plays only a small role in increasing the amplitude of bellows. Within the larynx of Pituophis is a "vocal cord," the laryngeal septum, which is a flexible, horizontal shelf of tissue that divides the anterior portion of the larynx. Removal of the laryngeal septum alters the defensive sounds and eliminates their harmonic elements. The laryngeal septum is unique among previously described vertebrate vocal cords or folds because it is supported by the cricoid (as opposed to arytenoid) cartilage and is a single (as opposed to bilaterally paired) structure.     

Broadband electrostatic acoustic transducer for ultrasonic measurements in liquids

A broadband capacitive electrostatic acoustic transducer (ESAT) has been developed for use in a liquid environment at megahertz frequencies. The ESAT basically consists of a thin conductive membrane stretched over a metallic housing. The membrane functions as the ground plate of a parallel plate capacitor, the other plate being a dc biased electrode recessed approximately 10 mum from the electrically grounded membrane. An ultrasonic wave incident on the membrane varies the membrane-electrode gap spacing and generates an electrical signal proportional to the wave amplitude. The entire assembly is sealed for immersion in a liquid environment. Calibration of the ESAT with incident ultrasonic waves of constant displacement amplitude from 1 to 15 MHz reveals a decrease in signal response with increasing frequency independent of membrane tension. The use of the ESAT as a broadband ultrasonic transducer in liquids with a predictable frequency response is promising.     

Structural behavior of alkali activated fly ash concrete. Part 2: structural testing and experimental findings

Alkali activated fly ash concrete (AAFAC) is an alternative form of concrete that uses coal fly ash as a 100 % replacement for ordinary portland cement (OPC). In this paper structural testing of nine steel reinforced AAFAC beams is explored. The test matrix included three over-reinforced, three under-reinforced, and three shear critical AAFAC beam samples, all tested in four point monotonic bending. For control purposes, an identical set of OPC concrete (OPCC) beams was fabricated and tested under identical conditions. Data collection during testing included load, deflection, top and side fiber concrete strains, and crack width. Test results show that AAFAC beams have very similar behavior to companion OPCC beams. This applies to load induced crack pattern, crack width magnitude, neutral axis location, flexural stiffness, and ultimate flexural and ultimate shear strengths. The research concludes that AAFAC flexural members can be designed using existing ACI 318-08 methods developed for OPCC, and that this applies to both the service and ultimate limit states.     

MALDI mass spectrometric imaging of cardiac tissue following myocardial infarction in a rat coronary artery ligation model

Although acute myocardial infarction (MI) is consistently among the top causes of death in the United States, the spatial distribution of lipids and metabolites following MI remains to be elucidated. This work presents the investigation of an in vivo rat model of MI using mass spectrometric imaging (MSI) and multivariate data analysis. MSI was conducted on cardiac tissue following a 24-h left anterior descending coronary artery ligation to analyze multiple compound classes. First, the spatial distribution of a small metabolite, creatine, was used to identify areas of infarcted myocardium. Second, multivariate data analysis and tandem mass spectrometry were used to identify phospholipid (PL) markers of MI. A number of lysophospholipids demonstrated increased ion signal in areas of infarction. In contrast, select intact PLs demonstrated decreased ion signal in the area of infarction. The complementary nature of these two lipid classes suggests increased activity of phospholipase A(2), an enzyme that has been implicated in coronary heart disease and inflammation.     

Advances in the diagnosis and management of scleroderma-related vascular complications

Vascular disease is observed in virtually all patients with systemic sclerosis and presents several challenges for the clinician. The alterations in vascular tone noted with Raynaud's phenomenon may have corollaries in both the pathogenesis and management of systemic sclerosis-related internal organ complications. Early recognition of isolated pulmonary hypertension, coronary microcirculatory disease, and scleroderma renal involvement may be the keys to successful outcomes. Future trends in the management of systemic sclerosis may be directed at preventing the development of these vascular syndromes. This may occur through combined therapies directed at the abnormal immune response, disregulated fibroblast function, and resultant abnormal vascular response.     

High-performance fully-depleted SOI RF CMOS

A T-gate structure has been implemented in the fabrication of fully depleted silicon-on-insulator MOSFETs. The T-gate process is fully compatible with the standard CMOS and the resulting reduction of gate-resistance significantly improved the RF performance. Measured f _max is 76 GHz and 63 GHz for n- and p-MOSFET with 0.2-μm gate length, respectively. At 2 GHz, a minimum noise figure of 0.4 dB was measured on an n-MOSFET with the T-gate structure     

Determinants of subsequent home health care nursing service use by hospitalized patients with cancer

BACKGROUND: The authors examined the extent to which specific patient characteristics and length of hospital stay were capable of independently explaining the use of home health care nursing services by hospitalized patients with cancer after discharge. METHODS: The current study represents a secondary analysis of a data set originally gathered to identify the home health care needs of patients with cancer. The sample involved 87 patients with cancer who received home health care after hospitalization and 43 patients who did not receive such services. RESULTS: A logistic regression analysis indicated that home health care use was related to patient age, length of hospital stay, and level of symptom distress. Specifically, the likelihood of home health care use was found to increase among subjects older than 50 years of age, subjects with hospital stays of more than 7 days (apparently related to surgery), and those who experienced moderate to high levels of symptom distress. CONCLUSIONS: The results indicate a need for home health care nurses to be skilled in the management of cancer symptoms and in the complex problems commonly experienced by the postsurgical patient with cancer.