bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Study of the Al–Mg–B Ternary Phase Diagram
Authors: Bodkin Richard , Herrmann Mathias , Coville Neil J. , Sigalas Iakovos 
Published: May 2009

Abstract
The Al
x
Mg(1 – x)B2 solid solution was studied at temperatures of 900, 1000, 1200 and 1400 °C using X-ray diffraction. From the obtained data, isothermal sections at 1000, 1200 and 1400 °C have been proposed for the Al – Mg – B ternary system. Based on these results there exists an equilibrium between Al and AlMgB14 at temperatures above 1000 °C.
Comparison of Depth-Sensing Indentation at Ultramicroscopic Contacts by Single- and Multiple-Partial-Unload Cycles
Authors: Nassirou Maissarath , Thurn Jeremy 
Published: May 2009

Abstract
Thin films typically exhibit variations in modulus and hardness with increasing indentation depth during depth-sensing indentation experiments at ultramicroscopic contacts (“nanoindentation”) because the measured stiffness response is affected by the substrate. There are three techniques commonly used to sample this variation in properties with depth: multiple indentations with increasing peak load, a single indentation with multiple-partial-unload cycles, and continuous stiffness measurement during a single indentation event. Experiments using the first two options were performed on a series of thin film systems and the method of multiple-partial-unloading found to have significant drawbacks when used at the sub-micron length scale that lead to erroneous conclusions.
The coupled FEM analysis of super-high angular speed polishing of diamond films
Authors: Huang S. T. , Zhou L. , Xu L. F. , Jiao K. R. 
Published: May 2009

AbstractSuper-high angular speed polishing of diamond films is a new polishing method. During the polishing process, the rotational velocity of the cast iron polishing plate is higher than that of conventional polishing methods, and friction between the polishing plate and the diamond film during rotary motion generates heat that creates a diffusion condition for carbon atoms. The temperature and strain energy density distributions of the polished surface directly affect the polishing quality of diamond films. In this paper, a three-dimensional thermo-mechanical coupled finite element analysis was employed to analyze the temperature and strain energy due to the friction between the polishing plate and the thick diamond film while the polishing plate rotates at super-high angular speed. The results indicate that when the diamond film and polishing plate rotate in the same direction, the differences of temperature and strain energy evidently decrease, and the temperature and strain energy in the diamond film become more uniform. The removal rate by super-high speed polishing has been quantitatively described by the diffusion mechanism, and it agrees well with the experiment data. This work will provide theoretical guidance to the design and operation of the super-high speed polishing of diamond films.
Micromagnetism of advanced hard magnetic materials
Authors: Kronmüller Helmut , Goll Dagmar 
Published: May 2009

Abstract
The continuum theory of micromagnetism has been found to be a rather effective tool to describe magnetic states and magnetization processes. In this paper some rigorous micromagnetic results obtained for characteristic magnetic properties of nanocrystalline hard magnetic materials will be outlined and their application to the development of outstanding magnetic materials will be discussed. In particular the role of exchange coupled composite systems will be considered and the effects of the microstructure will be investigated. Furthermore, the deteriorating effects of magnetically softened surface regions, the depinning and pinning of domain walls at phase boundaries, the remanence exchange enhancing effects and the depinning fields of domain walls of composite particles in the case of high-density recording systems will be discussed.
Recurrent hematomas following craniotomy for traumatic intracranial mass
Authors: Bullock Ross , Hannemann C. Oliver , Murray Lilian , Teasdale Graham M. 
Published: May 2009

✓ Of 850 patients who underwent craniotomy for evacuation of a traumatic intracranial mass, 59 (6.9%) developed a second hematoma at the operation site, which required a second operation. Compared to those who did not, patients who developed postcraniotomy hematoma (PCH) had a significantly higher incidence of evidence of alcohol intake and preoperative mannitol administration; a higher percentage had a bad outcome. Coagulopathy was frequent in PCH patients.
Although three-quarters of the initial hematomas were intradural, 69% of the PCH's were predominantly extradural. The large potential space underlying a craniotomy bone flap may predispose to development of a PCH. Intracranial pressure (ICP) was monitored in 39 of the 59 PCH patients, which allowed earlier detection of the PCH in 22 (56%). In 17 patients, the ICP failed to rise despite clinical deterioration, and detection of the PCH was delayed, significantly worsening the outcome in this group.
Saphenous vein graft bypass of the cavernous internal carotid artery
Authors: Sekhar Laligam N. , Sen Chandra N. , Jho Hae Dong 
Published: May 2009

✓ Saphenous vein graft reconstruction was performed from the petrous to the supraclinoid internal carotid artery (ICA) to replace the cavernous ICA in six patients during direct intracavernous operations. Four of these patients had intracavernous neoplasms with invasion of the ICA and two had intracavernous ICA aneurysms that could not be clipped or occluded with intraluminal balloons. All but one patient had evidence of poor collateral flow reserve in a balloon occlusion test of the ICA. The superficial temporal artery was not present in four patients, was minuscule in one, and was damaged during the initial dissection in another, making it unsuitable for superficial temporal-to-middle cerebral artery branch anastomosis.
Blood flow within the graft could not be established intraoperatively in one patient (who had excellent collateral circulation) due to the small size of the vein (3 mm). In all others, the grafts were patent on follow-up arteriography and transcranial Doppler studies. Three patients who had severe reduction of cerebral blood flow during test occlusion of the ICA exhibited temporary hemispheric neurological deficits postoperatively; the deficits were related to the duration of temporary ICA occlusion. All three recovered completely without evidence of infarction on computerized tomography (CT). One patient who clinically could not tolerate the balloon occlusion test of the ICA also had temporary neurological deficits with good recovery but showed evidence of border-zone infarction on CT scans. The present role of saphenous vein graft bypass of the cavernous ICA is discussed.
Postcallosotomy language impairments in patients with crossed cerebral dominance
Authors: Sass Kimberlee J. , Novelly Robert A. , Spencer Dennis D. , Spencer Susan S. 
Published: May 2009

✓ Language impairments were reviewed retrospectively in patients who underwent partial or total corpus callosum section for medically refractory secondary generalized epilepsy. Postoperatively, four of 32 patients had clinically significant language impairments that were not present prior to the operation. All involved primarily verbal output (speech and writing) and spared verbal comprehension. Written language skills (reading and spelling), verbal memory, and verbal reasoning abilities were impaired to varying degrees. These impairments were associated with crossed cerebral dominance. Three patients with severe speech difficulties after surgery were right hemisphere-dominant for speech and were right-handed. One left hemisphere speech-dominant, left-handed patient was agraphic after surgery, but spoke normally.
It is concluded from these data and from other reports in the literature that three syndromes of language disturbance may follow callosotomy. The first, involving speech difficulty but sparing writing, is attributable to buccofacial apraxia. The second involves speech and writing difficulties and occurs in right hemisphere-dominant right-handed patients. The third involves dysgraphia with intact speech and occurs in left hemisphere-dominant left-handed patients.
Surgical management of epilepsy associated with cerebral arteriovenous malformations
Authors: Yeh Hwa-Shain , Kashiwagi Shiro , Tew John M. , Berger Thomas S. 
Published: May 2009

✓ Between 1982 and 1986, 27 patients with seizure disorders due to cerebral arteriovenous malformation (AVM) were surgically treated by the authors. These patients had no history or clinical manifestation of intracranial hemorrhage. All were treated with anticonvulsant agents by their neurologists but became disabled due to inadequate control of seizures by medication, side effects of the anticonvulsant drugs, or the effects on their professional lives of even infrequent seizures. The age of the patients ranged from 13 to 61 years. There were 13 males and 14 females. The AVM's were smaller than 2 cm in four patients, between 2 and 4 cm in five, and larger than 4 cm in 18. The most frequent location of the AVM's was in the temporal lobe, followed by the frontal, parietal, and occipital lobes. All patients had preoperative electroencephalography (EEG) and intraoperative electrocorticography. Intraoperative recording of the amygdala and the hippocampus by depth electrodes was performed if the AVM's were located in the temporal lobe. Superficial or posterior temporal lobe AVM's often have remote seizure foci that involve the amygdala and hippocampus. All patients underwent craniotomy and total excision of their AVM's. Surgery was carried out under local anesthesia to allow localization by electrical stimulation if the AVM involved the speech area or the sensorimotor cortex. Based on the EEG findings, excision of the epileptogenic lesion in addition to the AVM was performed in 18 patients. In seven patients with AVM's located in the temporal lobe, remote seizure foci were identified and excised. The remote epileptic activity was particularly prominent in AVM's in the temporal lobe and usually involved mesial temporal structures.
Microscopic study of excised seizure foci showed gliosis in 26 cases, hemosiderin deposits in 10, and focal hemorrhage in four. There were no operative deaths. Two patients developed a hemiparesis and three suffered temporary dysphasia after surgery. Two patients had visual field deficits. The results of postoperative seizure control during the average follow-up period of 3 years 11 months were excellent in 21 patients, good in three, fair in two, and poor in one. The latter patient, whose epileptic lesion was not completely excised because of its location in the motor cortex, had poor seizure control postoperatively. Another patient required a second operation to remove a remote seizure focus.
In this series, proposed mechanisms of seizure associated with cerebral AVM include focal cerebral ischemia secondary to arteriovenous shunting, gliosis of the surrounding brain, and a secondary epileptogenesis in the temporal lobe. Successful seizure control can be obtained with wide excision of the epileptogenic foci surrounding the AVM's. In some circumstances, seizure foci remote from the vascular malformation must be excised.
Effect of clot removal on cerebral vasospasm
Authors: Inagawa Tetsuji , Yamamoto Mitsuo , Kamiya Kazuko 
Published: May 2009

✓ The effect of clot removal on cerebral vasospasm was studied in 104 patients with aneurysmal subarachnoid hemorrhage (SAH). The series included patients who fulfilled all of the following criteria: operation was performed by Day 3 after the ictus; the patient's preoperative clinical grade was between Grades I and IV; there was no rebleeding; computerized tomography (CT) showed only SAH; and carotid angiograms were performed by Day 2 and repeated between Days 7 and 9. Both the degree of SAH on CT and angiographic vasospasm were graded from 0 to III. The relationship of the SAH grade in the basal frontal interhemispheric fissure (IHF) to the presence of vasospasm at the A2 segments of the anterior cerebral artery and the relationship of the SAH grade in the sylvian stems to the presence of vasospasm at the M1 segments of the middle cerebral artery were analyzed.
Correlation of preoperative and postoperative SAH grades with the angiographic vasospasm grades, with the incidence of symptomatic vasospasm, and with the low-density area on CT could be found in the A2 and M1 territories. Decrease of cisternal blood measured by CT after the operation did not relate directly to the reduction of vasospasm. When the SAH was Grade II or III in the basal frontal IHF, the angiographic vasospasm grades at the A2 were significantly lower in patients with surgery via the interhemispheric approach than in those with surgery via the pterional approach. Symptomatic vasospasm occurred in two of the eight cases operated on by the interhemispheric approach compared with 11 of the 22 cases approached via the pterional route. In patients with a pterional approach, there was no significant difference in severity of vasospasm in the M1 territory between the side of approach and the opposite side. No consistent relationship could be found between the time interval from SAH to operation and the severity of vasospasm. While clot removal may ameliorate cerebral vasospasm, its effect per se does not seem to be significant.
The effect of fetal mesencephalon implants on primate MPTP-induced parkinsonism
Authors: Bankiewicz Krzysztof S. , Plunkett Robert J. , Jacobowitz David M. , Porrino Linda , di Porzio Umberto , London William T. , Kopin Irwin J. , Oldfield Edward H. 
Published: May 2009

✓ Parkinsonism or hemiparkinsonism was induced by administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in four rhesus monkeys, which then received homologous fetal mesencephalon implants into the caudate nuclei. Cavities were prepared in the medial caudate nucleus 2 to 5 weeks before the fetal grafts were implanted. Control studies were conducted in unoperated MPTP-treated animals. Significant behavioral improvement, which occurred within weeks of implantation of fetal mesencephalon, was sustained for up to 7 months. No recovery was seen in the unoperated control animals. Histological examination revealed numerous surviving tyrosine hydroxylase (TH)-immunoreactive cell bodies. In addition to the graft, abundant TH-immunoreactive fibers were observed in the host caudate nucleus ventral to the region of the implanted and the nonimplanted cavities. Since TH-immunoreactive cell bodies of the substantia nigra compacta (A-9 cells) were destroyed by MPTP treatment and the ventral tegmental area (A-10) remained intact, it is concluded that sprouting of remaining host dopaminergic fibers occurs. These newly formed fibers appeared to emanate from the mesolimbic projection to the striatum. It is likely that the newly sprouted dopaminergic fibers account for the motor improvement elicited by precavitation and fetal mesencephalon implantation.
These results suggest that the mechanism of recovery of parkinsonian primates after implantation of fetal dopaminergic tissue into the caudate nucleus is by stimulation of sprouting from host neurons. They also suggest that, with identification of the factors responsible for the formation of the new dopaminergic neuronal processes and with further development, tissue implantation may be an effective therapy for Parkinson's disease in humans.
Immunohistochemical demonstration of DNA polymerase α in human brain-tumor cells
Authors: Kunishio Katsuzo , Mishima Nobuya , Matsuhisa Takashi , Tsuno Kazuyuki , Matsumi Nobuhiko , Satoh Toru , Matsumoto Kengo , Furuta Tomohisa , Nishimoto Akira , Shiraishi Tetsuya 
Published: May 2009

✓ The proliferative capacity of brain-tumor cells was analyzed in vitro and in situ using monoclonal antibody (MAb) against deoxyribonucleic acid (DNA) polymerase α. For the in vitro studies, two cultured human glioma cell lines were investigated using MAb against DNA polymerase α, the MAb Ki-67, a serum against proliferating cell nuclear antigen (PCNA/cyclin), bromodeoxyuridine (BUdR), and an anti-BUdR MAb. During exponential growth of the cells, the percentage of polymerase α-positive cells (the “polymerase α score”) ranged from 72.0% to 77.1%, the Ki-67-positive cells (the “Ki-67 score”) ranged from 43.4% to 59.4%, the PCNA/cyclin-positive cells from 30.9% to 41.4%, and the BUdR labeling index from 28.6% to 39.3%.
For the in situ studies, tissue from 60 human brain tumors and from two normal human brains was investigated and the polymerase α scores and Ki-67 scores were compared. In normal brain tissue, no immunostaining was found by either method. In brain tumors, both the polymerase α scores and the Ki-67 scores correlated with the histological grade of malignancy. Polymerase α scores were generally higher than Ki-67 scores in the same specimen, especially in malignant brain tumors.
These findings suggest that immunostaining of DNA polymerase α is a convenient and important new method by which to estimate the cellular proliferation rate of brain tumors. Polymerase α scores may be closer to the growth fraction of the individual tumor than the MAb Ki-67 or other scores.
Diagnosis and microsurgical approach to far-lateral disc herniation in the lumbar spine
Authors: Maroon Joseph C. , Kopitnik Thomas A. , Schulhof Larry A. , Abla Adnan , Wilberger James E. 
Published: May 2009

✓ Lumbar-disc herniations that occur beneath or far lateral to the intervertebral facet joint are increasingly recognized as a cause of spinal nerve root compression syndromes at the upper lumbar levels. Failure to diagnose and precisely localize these herniations can lead to unsuccessful surgical exploration or exploration of the incorrect interspace. If these herniations are diagnosed, they often cannot be adequately exposed through the typical midline hemilaminectomy approach. Many authors have advocated a partial or complete unilateral facetectomy to expose these herniations, which can lead to vertebral instability or contribute to continued postoperative back pain.
The authors present a series of 25 patients who were diagnosed as having far lateral lumbar disc herniations and underwent paramedian microsurgical lumbar-disc excision. Twelve of these were at the L4–5 level, six at the L5–S1 level, and seven at the L3–4 level. In these cases, myelography is uniformly normal and high-quality magnetic resonance images may not be helpful. High-resolution computerized tomography (CT) appears to be the best study, but even this may be negative unless enhanced by performing CT-discography. Discography with enhanced CT is ideally suited to precisely diagnose and localize these far-lateral herniations. The paramedian muscle splitting microsurgical approach was found to be the most direct and favorable anatomical route to herniations lateral to the neural foramen. With this approach, there is no facet destruction and postoperative pain is minimal. Patients were typically discharged on the 3rd or 4th postoperative day. The clinical and radiographic characteristics of far-lateral lumbar-disc herniations are reviewed and the paramedian microsurgical approach is discussed.
Prediction of stability of cervical spine fracture managed in the halo vest and indications for surgical intervention
Authors: Sears William , Fazl Mahmood 
Published: May 2009

✓ A retrospective study was made of 173 cases of acute cervical spine injury with halo vest management to compare initial injury features with outcome. The object was to determine whether a mathematical model could be developed enabling a prediction to be made at the time of the initial assessment as to the probability of success or failure of conservative management using the halo vest alone, and thus perhaps avoid lengthy, unsuccessful treatment.
Patients with facet joint dislocation were found to form a distinct subgroup of the injury population. Of the 70 patients in this subgroup, 44% achieved stability with the halo vest alone, but half of these had a “poor anatomical result.” No mathematical model or associated injury features could be found to assist in the outcome prediction in this subgroup. Of the 103 patients without facet joint dislocation, 70% achieved stability with the vest alone and over 75% of these had a “good anatomical result.” A useful model of outcome prediction was found for this subgroup by logistic regression analysis; the two most important predictors in the model were the amount of subluxation and the degree of angulation in the sagittal plane.
Aneurysms of the ophthalmic segment
Authors: Day Arthur L. 
Published: May 2009

✓ The clinical, radiographic, and anatomical features in 80 patients with ophthalmic segment aneurysms were reviewed, and were categorized according to a presumed origin related to the ophthalmic (41 cases) or superior hypophyseal (39 cases) arteries. There was a marked female predominance (7:1) and high incidence of multiple aneurysms (45%) within this population. Clinical presentations included subarachnoid hemorrhage in 23 cases (29%) and visual deficits in 24 (30%); five patients exhibited both hemorrhage and visual loss. Twenty-eight aneurysms were incidentally identified.
Ophthalmic artery aneurysms arose from the internal carotid artery (ICA) just distal to the ophthalmic artery, pointed superiorly or superomedially, and (when large) deflected the carotid artery posteriorly and inferiorly, closing the siphon. Abnormalities relating to vision were not identified until the aneurysm realized giant proportions. The optic nerve was typically displaced superomedially, which restricted contralateral extension until late in the clinical course; unilateral nasal field loss was seen in 12 patients. Nine patients had bilateral ophthalmic artery aneurysms which were often clipped via a unilateral craniotomy.
Superior hypophyseal artery aneurysms arose just above the dural ring from the medial bend of the ICA, at the site of perforator origin to the superior aspect of the hypophysis, and had no direct association with the ophthalmic artery. The carotid artery was usually located lateral or superolateral relative to the aneurysm. These lesions could extend medially beneath the chiasm (suprasellar variant), producing a clinical and computerized tomography picture similar to a pituitary adenoma, or they could extend ventrally to burrow beneath the anterior clinoid process (paraclinoid variant).
Preoperative categorization of these lesions according to their likely branch of origin provides excellent correlation with visual deficits and operative findings, and has allowed the author to clip 52 of 54 lesions, with very low operative or visual morbidity.