Research on personal epistemologies (Hofer & Pintrich, 2002) has mostly conceptualized them as stable beliefs or stages of development. On these views, researchers characterize individual students' epistemologies with single, coherent descriptions. Evidence of variability in Student epistemologies, however, suggests the need for more complex models. Hammer and Elby (2002) proposed modeling personal epistemologies as comprised of manifold epistemological resources.This difference in ontology-the form research attributes to cognitive structure-accounts for variability: The activation of these epistemological resources depends on context. Our purpose in this article is to argue that it also accounts for coherences in student epistemologies, in particular for multiple local coherences. We advance this argument using a case study of a 15-min discussion by a group of eighth graders about the "rock cycle" (the cyclic transformations of rock among different forms). We begin with evidence of the students' working from a stable, coherent epistemological stance. Then, after a brief, purely epistemological intervention by the teacher, the evidence indicates they are working from a different but also coherent and stable epistemological stance.

According to many scholars, classrooms in America are overwhelmingly authoritarian and undemocratic. They focus on fragmented knowledge that is disconnected from the students' lives. Proven reforms are resisted at all levels, and systematic progressive change is non-existent nearly a century after the progressive movement. Why is this so? The standard liberal outlook is that the schools are 'broken' and 'neglected', but that they have the potential, with reform, to be a major progressive force in society. This paper questions these assumptions through a review of the seminal educational-economic work by Bowles and Gintis: Schooling in Capitalist America [I]. The major claim of this text is that our educational system's primary role is to mirror, support, stabilize, and reproduce the fundamentally hierarchical and undemocratic social relationships that exist in the majority of American workplaces. The major arguments and evidence of this text are reviewed, and implications for PER will be briefly mentioned.

Generalized quantum mechanics is used to examine a simple two-particle scattering experiment in which there is a bounded region of closed timelike curves (CTCs) in the experiment's future. The transitional probability is shown to depend on the existence and distribution of the CTCs. The effect is therefore acausal, since the CTCs are in the experiment's causal future. The effect is due to the nonunitary evolution of the pre- and postscattering particles as they pass through the region of CTCs. We use the time-machine spacetime developed by Politzer, in which CTCs are formed due to the identification of a single spatial region at one time with the same region at another time. For certain initial data, the total cross section of a scattering experiment is shown to deviate from the standard value (the value predicted if no CTCs existed). It is shown that if the time machines are small, sparsely distributed, or far away, then the deviation in the total cross section may be negligible as compared to the experimental error of even the most accurate measurements of cross sections. For a spacetime with CTCs at all points, or one where microscopic time machines pervade the spacetime in the final moments before the big crunch, the total cross section is shown to agree with the standard result (no CTCs) due to a cancellation effect.

The combined retrolabyrinthine-retrosigmoid (CRR) approach utilizes anterior retraction of the sigmoid sinus to improve exposure of the posterior fossa without cerebellar retraction. The CRR was initially used for vestibular neurectomy but is now utilized for acoustic neuroma excision with hearing preservation and exposure for clipping of basilar and vertebrobasilar aneurysms. This excellent exposure of the cerebellopontine angle without cerebellar retraction can be used for all posterior fossa exposures.

In this study, the results of 76 revision stapes surgeries performed from 1974 to 1992 were reviewed. Either the KTP or the argon laser was used in 40 operations. Prosthesis problems were the most common cause for revision (63%) followed by eroded/ necrotic incus (29%) and adhesions (29%). Overall “success” in air‐bone gap closure (air‐bone gap ≤ 10 dB) was 46% for first revisions and 33% for second or greater revisions. The “improvement” rate (air‐bone gap ≤ 20 dB) was 65% for first revisions and 53% for second or greater revisions. There was no statistically significant difference in hearing results between laser surgery and conventional technique. However, an absence of adhesions was noted when the laser had been used in the primary procedure.

During the last decade, vestibular neurectomy has become a more frequently performed procedure to cure symptoms of inner ear vertigo while preserving hearing. In an effort to determine the results of vestibular neurectomy across the country, a questionnaire was prepared and sent to the 350 members of the American Otologic Society and the American Neurotology Society. Results of that survey indicated that 2,820 vestibular neurectomy procedures were performed by 58 surgeons. Ninety-two percent (2,590 cases) were performed through the posterior fossa approach. Of these, 1149 cases (44%) were through the retrolabyrinthine approach, 940 cases (36%) were through the retrosigmoid approach, 307 cases (12%) were through the combined retrolabyrinthine-retrosigmoid approach, and 194 cases (8%) were unspecified as to which posterior fossa approach was used. The remaining 230 cases (8%) were through the middle fossa approach. Sectioning of the vestibular nerve was done by the otologist in 58 percent of cases, by the neurosurgeon in 12 percent, and by either surgeon in 30 percent. Classic Meniere's disease, the most common indication for vestibular neurectomy, resulted in the best cure rate of 91 percent. Other inner ear diseases such as traumatic labyrinthitis and vestibular neuronitis had a lower cure rate of 74 to 81 percent. Hearing was preserved to within 20 dB of the preoperative pure-tone thresholds in 87 percent. There were no deaths, 11 cases of meningitis and 16 cases of facial paralysis, 15 of which occurred after middle fossa surgery, representing a 7 percent incidence of facial paralysis after middle fossa surgery. Eleven of the 15 cases resulted in permanent paralysis and four in temporary paralysis.(ABSTRACT TRUNCATED AT 250 WORDS)

The LaryngoscopeVolume 102, Issue 12 p. 1395-1398 Article Documentation is a snap Herbert Silverstein M.D., Corresponding Author Herbert Silverstein M.D. Ear Research Foundation, Sarasota, Fla.The Ear Research Foundation, 1901 Floyd St., Sarasota, FL 34239Search for more papers by this authorMichael Seidman M.D., Michael Seidman M.D. Ear Research Foundation, Sarasota, Fla.Search for more papers by this authorSeth Rosenberg M.D., Seth Rosenberg M.D. Ear Research Foundation, Sarasota, Fla.Search for more papers by this author Herbert Silverstein M.D., Corresponding Author Herbert Silverstein M.D. Ear Research Foundation, Sarasota, Fla.The Ear Research Foundation, 1901 Floyd St., Sarasota, FL 34239Search for more papers by this authorMichael Seidman M.D., Michael Seidman M.D. Ear Research Foundation, Sarasota, Fla.Search for more papers by this authorSeth Rosenberg M.D., Seth Rosenberg M.D. Ear Research Foundation, Sarasota, Fla.Search for more papers by this author First published: December 1992 https://doi.org/10.1288/00005537-199212000-00017Citations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume102, Issue12December 1992Pages 1395-1398 RelatedInformation

In patients with Menière's disease, the possibility of developing Menière's disease in the uninvolved ear is of great concern. In this study, the incidence of bilateral Menière's disease (BMD) in medically treated patients was found to be 17 percent, while in surgically treated patients it was significantly lower, 5.9 percent (p less than 0.01). The incidence of BMD for each surgical procedure was as follows: 9 percent after endolymphatic subarachnoid shunt (n = 101), 7 percent after cochleovestibular neurectomy (n = 100), 6 percent after cochleosacculotomy (n = 18), and 0 percent after vestibular nerve section (n = 73). The average duration of disease prior to surgery was 6.3 years. Seventy-two percent of the patients who developed BMD did so within 5 years of the onset of their symptoms. Proper patient selection is the most likely explanation for the low incidence of BMD among surgically treated patients.

Otolaryngology–Head and Neck SurgeryVolume 104, Issue 1 p. 139-140 Original Articles Auditory and vestibular function after vestibular neurectomy Seth Rosenberg MD, Seth Rosenberg MD Ear Research Foundation, Sarasota, FloridaSearch for more papers by this authorHerbert Silverstein MD, Corresponding Author Herbert Silverstein MD n/a@dne.dne Ear Research Foundation, Sarasota, FloridaReprint requests: Herbert Silverstein, MD, Ear Research Foundation, 1901 Floyd St., Sarasota, FL 34239.Search for more papers by this authorHorace Norrell MD, Horace Norrell MD Ear Research Foundation, Sarasota, FloridaSearch for more papers by this authorDavid White MD, David White MD Ear Research Foundation, Sarasota, FloridaSearch for more papers by this author Seth Rosenberg MD, Seth Rosenberg MD Ear Research Foundation, Sarasota, FloridaSearch for more papers by this authorHerbert Silverstein MD, Corresponding Author Herbert Silverstein MD n/a@dne.dne Ear Research Foundation, Sarasota, FloridaReprint requests: Herbert Silverstein, MD, Ear Research Foundation, 1901 Floyd St., Sarasota, FL 34239.Search for more papers by this authorHorace Norrell MD, Horace Norrell MD Ear Research Foundation, Sarasota, FloridaSearch for more papers by this authorDavid White MD, David White MD Ear Research Foundation, Sarasota, FloridaSearch for more papers by this author First published: 01 January 1991 https://doi.org/10.1177/019459989110400130Citations: 1 Presented at the Annual Meeting of the American Neurotologic Society, Palm Beach, April 27, 1990. AboutPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume104, Issue1January 1991Pages 139-140 RelatedInformation

Facial nerve monitoring is one of the most exciting innovations in otologic surgery in the past decade. Intraoperative monitoring has been shown to reduce the probability of iatrogenic injury to the facial nerve during surgery. It saves surgical time and reduces the anxiety level of both patients and surgeons. There are several reasons to use facial nerve monitoring: The surgeon nerve knows when it will be needed in a particular case, the operating room personnel become familiar with the equipment, and the surgeon learns how to interpret the sounds produced by the monitor and how to correlate them with surgical manipulations around the facial nerve. Facial nerve monitoring has added another dimension of safety to otologic and neurotologic surgery and has reduced the incidence of facial weakness or paralysis in the authors' surgical practice.

Since introducing the retrolabyrinthine vestibular neurectomy in 1978, we have performed 78 procedures with good results. In 1985 we introduced the retrosigmoid-IAC vestibular neurectomy, which allows a more complete transection of the vestibular nerves within the internal auditory canal (IAC). Vertigo control has been excellent; however, in 75% of patients, postoperative headaches have been a significant problem. In 1987, the best aspects of the two procedures were incorporated and the combined retrolab-retrosigmoid vestibular neurectomy was developed. The procedure is similar to the RVN in that all bone covering the lateral venous sinus is removed. It differs from the RVN in that a limited mastoidectomy is performed and the dura is opened just behind the LVS. The LVS is retracted forward, exposing the cerebellopontine angle. This allows the surgeon the option to section the vestibular nerve in either the CP angle or the IAC, depending upon the presence or absence of a cochieovestibular cleavage plane in the CP angle. The results have been good and the incidence of headache has been reduced to 10%. The technique, results, and complications are reported here.

Between 1925 and 1945, Walter Dandy and Kenneth McKenzie performed more than 700 posterior fossa eighth nerve sections and vestibular neurectomies to treat the intractable vertigo accompanying Ménière's disease. During the past 10 years, with the aid of microsurgical techniques and the approach to the posterior fossa through the temporal bone, vestibular neurectomy has undergone a resurgence of popularity. When hearing is to be preserved, vestibular neurectomy is the surgical treatment of choice for patients who fail to undergo a remission of the vertigo attacks of Ménière's disease. This report reviews 115 consecutive vestibular neurectomies performed from 1978 to 1988 for the treatment of Ménière's disease. In 1978, retrolabyrinthine vestibular neurectomy (RVN), a procedure in which the posterior fossa is entered anterior to the sigmoid sinus and behind the labyrinth, was introduced. During the last 3 years, the approach to the posterior fossa has been a small dural opening behind the sigmoid sinus; this approach is known as the combined retrolabyrinthine retrosigmoid approach. There have been no cases of facial paralysis and no serious complications connected with this technique. A high incidence of headache (50%) resulted when the posterior wall of the internal auditory canal was drilled away for better exposure. Transient cerebrospinal fluid (CSF) leaking occurred in 7% of the patients undergoing RVN; however, no CSF leaks occurred when the combined retrolabyrinthine retrosigmoid approach was used. In the RVN series, wound infection occurred in 20% of the cases until perioperative antibiotics reduced the rate to 3%. The results in terms of curing or improving vertigo have been excellent (94%), and hearing has been preserved to within 20 dB preoperative levels in 76% of the cases. Until a cure for Ménière's disease is found, microsurgical posterior fossa vestibular neurectomy remains the best treatment.

The results of 33 small fenestra stapedotomies performed using conventional techniques were compared with the results of 33 stapedotomies performed using the argon or KTP laser. The ossicular chain was reconstructed using a Teflon wire piston of 0.6 mm diameter, and follow-up was at least 1 year. Over-closure of the air-bone gap or closure to within 10 dB was accomplished in 91% of the laser-treated group versus 72% of the conventionally treated group (p less than 0.10). The hearing results were statistically better in the laser group (p less than 0.05). Transient delayed vestibular symptoms, lasting from 1 to 3 weeks, were present in 39% of the laser-treated group and in 12% of the patients treated by conventional techniques (p less than 0.05). The KTP laser stapedotomy, using a micromanipulator mounted on the microscope, is a safe, efficient technique that reduces some of the technical difficulties associated with conventional stapes surgery. The main advantage of the laser is that it enables the surgeon to make an atraumatic, bloodless opening in a fixed or mobile stapes footplate without mechanical manipulation of the stapes. Using a lower wattage to vaporize the footplate and waiting several seconds between laser bursts may decrease the incidence of postoperative vestibular symptoms. The use of the KTP laser in stapes surgery represents a major advance in surgery for otosclerosis.