MAVEN observations of the response of Mars to an interplanetary coronal mass ejection.

Coupling between the lower and upper atmosphere, combined with loss of gas from the upper atmosphere to space, likely contributed to the thin, cold, dry atmosphere of modern Mars. To help understand ongoing ion loss to space, the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft made comprehensive measurements of the Mars upper atmosphere, ionosphere, and interactions with the Sun and solar wind during an interplanetary coronal mass ejection impact in March 2015. Responses include changes in the bow shock and magnetosheath, formation of widespread diffuse aurora, and enhancement of pick-up ions. Observations and models both show an enhancement in escape rate of ions to space during the event. Ion loss during solar events early in Mars history may have been a major contributor to the long-term evolution of the Mars atmosphere.

Educating the rehabilitation engineer as a service provider.

This paper reviews a 12-month masters-level rehabilitation engineering training program to prepare engineers to be rehabilitation service providers. The extent of the rehabilitation engineering shortage is discussed. The curriculum is then provided with descriptions of 16 courses, the program's internship, and a comparison with other training programs. A listing of the intended customers of the program graduates is given along with a description of the advisory committee to help interface with these customers. Four educational goals consisting of disability and technology, major rehabilitation systems, applied skills, and life-long learning are discussed. The results of six years' experience with this program, including a survey of graduates, are presented.

Intracorneal nuclear dust aggregates in dermatitis herpetiformis. A clue to diagnosis.

Dermatitis herpetiformis has a characteristic histologic pattern consisting of subepidermal blisters often containing fibrin, infiltrates of neutrophils and nuclear dust at tips of dermal papillae, and papillary dermal edema. These are features of early and evolving lesions. We present two cases of clinically typical dermatitis herpetiformis with previously unreported histologic features that may provide a significant diagnostic clue. In each of these cases there were focal collections of nuclear dust in the cornified layer of the epidermis, a finding that may represent a resolving phase of dermatitis herpetiformis, beyond the usual papillary dermal neutrophilic microabscesses seen in early lesions. Biopsy material was available for immunofluorescent studies in one of the cases presented. In addition to the granular pattern of IgA positivity at the dermal-epidermal junction, which is diagnostic of dermatitis herpetiformis, this biopsy also showed similar IgA positivity in the intracorneal nuclear dust aggregates. In the second case, initial sections showed only intracorneal nuclear dust, but at deeper levels there were more typical diagnostic microabscesses at the tips of dermal papillae.

Blistering distal dactylitis caused by Staphylococcus aureus.

Blistering distal dactylitis is a superficial infection of the anterior fat pad on the volar surface of the distal portion of ordinarily a single finger. Although most commonly caused by group A beta-hemolytic streptococci, we report a case of blistering distal dactylitis caused by Staphylococcus aureus involving all the fingers and thumbs of a child. After results of a Gram's stain and culture established the diagnosis, the child responded rapidly to oral amoxicillin trihydrate/clavulanate potassium (Augmentin). Multiple fingers affected in blistering distal dactylitis may be a predictor of S. aureus as the causative agent.

Effect of autogenous marrow and calcitonin on reactions to a ceramic.

The effect of autogenous marrow and calcitonin on reactions to a tricalcium phosphate ceramic was studied by subcutaneous implantation in rats. No bone formation was evident in association with uncoated and calcitonin-coated ceramic. At four weeks and thereafter bone formation was evident in association with all marrow-coated implants.

The effect of levamisole on DMBA-induced carcinogenesis in the hamster cheek pouch.

The effect of levamisole on DMBA-induced carcinogenesis in the cheek pouch of the hamster was studied. Findings indicate that levamisole modified the response of the pouch to DMBA at six weeks, while this effect was not maintained after 12 weeks of DMBA application.

Long-term study of pulp capping in monkeys with three agents.

The pulps of 40 permanent teeth of two monkeys were mechanically exposed and contaminated with adjacent saliva or plaque for 3 to 5 1/2 hours. The pulps were then capped with either Keflin (an antibiotic), Durelon (a polycarboxylate cement), or Dycal (a calcium hydroxide compound). Varnish and then amalgam were inserted. Each monkey received at least one dose of Procion red H-8BS vital dye. The teeth were extracted from one monkey 23 months after capping and from the other monkey 29 months after capping. Serial, decalcified, 7 mum-thick paraffin sections were prepared. Alternate slides were stained with hematoxylin ane eosin. Unstained sections were examined for Procion labeling, and selected slides were stained by the Brown-Brenn method for bacteria. Of 13 teeth capped with Keflin, only 4 responded satisfactorily. All of the Dycal and Durelon-capped pulps were successful at both time intervals. All of the Dycal-capped pulps showed complete bridging and no inflammation or pulp obliteration. Bridging was complete in only three of the Durelon-capped pulps. The findings of this study support the findings in our previous study3 and further substantiate the effectiveness of Dycal as a pulp-capping agent. The often-repeated claim that calcium hydroxide compounds exert a persistent stimulating effect on the pulp resulting in its eventual obliteration was not supported. Durelon is not recommended for pulp capping since the material apparently lacks an antibacterial effect and does not stimulate reparative dentinogenesis at the exposure site. The low rate of satisfactory responses of pulps capped with Keflin, as used, precludes its use of pulp capping.

Clinical evaluation of the (+) isomer of mepivacaine.

A human clinical study was undertaken to evaluate the effectiveness and safety of dexivacaine 2 per cent, mepivacaine 2 per cent, and mepivacaine 3 per cent. A double-blind technique was used to evaluate time of onset, duration, depth of anesthesia, and side effects. Results indicated no significant differences among the three anesthetics, except that mepivacaine 3 per cent had a significantly longer duration of soft-tissue symptoms in the mandibular block series. The few side effects noted were minimal and of no statistical significance. The evaluation of an anesthetic by the several parameters employed and especially by the over-all opinion of the anesthesia was deemed a valuable research method whem comparing the clinical effectiveness of local anesthetics.