Mass Size (mass + size)

Distribution by Scientific Domains


Selected Abstracts


Brochosome influence on parasitisation efficiency of Homalodisca coagulata (Say) (Hemiptera: Cicadellidae) egg masses by Gonatocerus ashmeadi Girault (Hymenoptera: Mymaridae)

ECOLOGICAL ENTOMOLOGY, Issue 5 2005
Hans-Paul Velema
Abstract., 1.,Many cicadellid females in the tribe Proconiini (Hemiptera: Cicadellidae) cover their egg masses with specialised, usually rod-shaped, brochosomes as the eggs are being laid. The brochosomes are produced in Golgi complexes in the Malpighian tubules of Cicadellidae. In contrast to the gravid females, adult males, pre-reproductive adult females, and nymphal males and females produce specialised, usually spherically shaped brochosomes. Brochosomes are also used to cover the external surfaces of nymphs and newly moulted adult males and females. 2.,The function of the brochosome covering the egg masses is unknown but various hypotheses have been suggested, including protecting the eggs against pathogens, predators, and parasitoids. Based on preliminary observations of Gonatocerus ashmeadi Girault (Hymenoptera: Mymaridae) parasitising the eggs of the cicadellid, Homalodisca coagulata (Say), it is speculated here that brochosomes covering an egg mass hinder parasitisation of eggs by G. ashmeadi. This hypothesis was tested by observing G. ashmeadi females foraging on leaves with H. coagulata egg masses heavily covered with rod-shaped brochosomes vs. those lacking brochosomes. 3.,Cox's proportional hazards model was used to evaluate the probability, per unit time, that a female G. ashmeadi displayed the sequence of behaviours that ended in successful oviposition as influenced by five variables: (a) presence or absence of brochosomes on an egg mass, (b) the leaf surface, upper or lower, being searched by the parasitoid (the egg masses are laid in the parenchyma on the lower leaf surface), (c) the parasitoid's previous ovipositional experience, (d) egg mass size, and (e) the parasitoid's age. 4.,Brochosomes significantly decreased oviposition efficacy of G. ashmeadi females. Scanning electron microscopy showed that females exposed to brochosome-covered egg masses had brochosomes adhering to their tarsi, legs, antennae, and eyes, all of which prompted extensive bouts of grooming. [source]


Life-threatening haemorrhage from a sternal metastatic hepatocellular carcinoma

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 6 2000
Chih-Yen Chen
Abstract Rupture of the tumour is a catastrophic complication of hepatocellular carcinoma. The prognosis in patients with a ruptured hepatocellular carcinoma is usually unfavourable. We describe a 46-year-old man who suffered from visible massive tumour haemorrhage due to a hepatitis B-related hepatocellular carcinoma that metastasized to the sternal bone. The prominent tumour mass was bulging over the anterior chest wall on the sternum of the patient, and bled spontaneously. This episode of life-threatening haemorrhage was stopped by surgical ligation of the bleeding site. Palliative radiotherapy shrank the tumour mass size and prevented further possible bleeding. This is likely to be the first reported case with a visible spontaneous tumour bleeding from a sternal metastatic hepatocellular carcinoma. [source]


Nontuberculous Mycobacteria-Induced Parotid Lymphadenitis Successfully Limited With Clarithromycin and Rifabutin

THE LARYNGOSCOPE, Issue 8 2004
Maulik B. Shah
Abstract Objectives/Hypothesis: Nontuberculous mycobacterial adenitis of the parotid gland is often difficult to diagnose. The rarity of these infections in the parotid region and the lack of specific guidelines pose a treatment challenge to the clinician. Three cases of nontuberculous mycobacterial adenitis are presented, with clinical response to antibiotics before surgery. Study Design: Retrospective chart review was made of children up to 18 years of age presenting with a parotid mass diagnosed as nontuberculous mycobacterial infection. Methods: Three patients (age range, 15 to 30 mo) with nontuberculous mycobacteria-induced parotid lymphadenitis were treated with a combination antibiotic regimen of clarithromycin and rifabutin or with clarithromycin alone. Results: All three patients responded clinically to the antibiotic treatment as evidenced by a smaller mass size and resolution of the overlying discoloration. Subsequent parotidectomy or biopsy appeared to be easier to perform because of decreased inflammation and edema and a more readily dissectible facial nerve. Conclusion: Children with nontuberculous mycobacteria-induced parotid lymphadenitis should be started on a trial of antibiotic treatment before surgery. Although surgery remains the definitive treatment modality, a larger study of preoperative antibiotic use against nontuberculous mycobacterial adenitis of the parotid in children is necessary. [source]


High-sensitivity surface micromachinable accelerometer using a ferroelectric substrate and its characterization

IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 3 2007
Seiji Aoyagi Member
Abstract The present study reports the fabrication and characterization of a high-sensitivity surface micromachinable accelerometer using a ferroelectric material having a large dielectric constant, such as bulk PZT (,r = 2600). The measurement principle is the detection of capacitance change with respect to the dielectric mass movement in the fringe electrical field. Considering the practical fabrication, a ferroelectric material is used for the substrate instead of the suspended proof mass. Since capacitance is increased not mechanically but electrically, high sensitivity can be expected while maintaining mechanical stiffness, which has the advantage of preventing touch down of the proof mass and widening the allowable measuring range of acceleration. A fabricated sensor is characterized. A high sensitivity of several sub-pF/g is confirmed, which is hundreds of times higher compared to that of a sensor fabricated using the Parylene polymer (,r = 3.15). This sensitivity is an order higher compared to those of other reported capacitive microaccelerometers, which have comparable proof mass sizes and comparable detectable acceleration ranges to the newly fabricated sensor. Copyright © 2007 Institute of Electrical Engineers of Japan© 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source]