bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinetics and Mechanism of the Permanganate-Induced Autocatalytic Dehydration Reaction of L-Y-Amino-N-Butyric Acid to Give 2-Pyrrolidone through a Radical Intermediate in Moderately Concentrated Acidic Medium
Authors: Bahrami Homayoon , Bigdeli Moghadas , Davari Mehdi D. , Zahedi Mansour , Moosavi-Movahedi Ali A. 
Published: May 2011

The reaction kinetics and mechanism of the permanganate ion oxidation of L-y-amino-butyric acid (GABA) in moderately concentrated sulfuric acid medium has been investigated spectrophotometrically. The product of this reaction is 2-pyrrolidone, which is a 5-membered lactam structure compound (gamma-butyrolactam). Conclusive evidence indicates autocatalytic activity for Mn(II) in this reaction, analogous to that of some a- amino acids. It has been shown that such activity appears when a certain concentration ratio of Mn(II) to GABA is built up in the medium, termed the “critical ratio”. The magnitude of this ratio depends on the sulfuric acid concentration. In considering the “delayed autocatalytic behaviour” of Mn(II) ions, rate equations satisfying our observations for both the catalytic and non- catalytic routes have been presented. The reaction shows a first-order dependence on permanganate ion concentration both in the catalytic and non-catalytic pathways, and an apparent first-order dependence on Mn2+ ions in the catalytic pathway. Also, it was found that the variation in the apparent rate constants of the catalytic and non-catalytic pathways versus the GABA concentration follows saturation curves. The correspondence of the pseudo-order rate constants of the catalytic and non-catalytic pathways to the Arrhenius and Eyring laws have verified the “critical ratio” as well as the “delayed autocatalytic behaviour” concepts. The activation parameters associated with both pathways have been computed and discussed. Mechanisms for both catalytic and non-catalytic routes involving radical intermediates, as well as a product having a lactam skeleton, are reported.
La crise ivoirienne et les migrants burkinabés
Authors: Courtin Fabrice , Fournet Florence , Solano Philippe 
Published: May 2011

Résumé Environ un million de personnes ont migré suite au conflit qui a éclaté le 19 septembre 2002 en Côte d’Ivoire. Parmi elles, 550 000 se sont déplacées à l’intérieur de la Côte d’Ivoire et 360 000 Burkinabés se sont déplacés vers le Burkina Faso. Cet article analyse les conséquences de l’arrivée de ces migrants sur le peuplement et sur le paysage de deux zones d’accueil au sud-ouest distants de deux cents kilomètres. Il ouvre une perspective nouvelle sur les migrations internes africaines et montre des impacts très différenciés.
Entre « renaissance » africaniste et interrogations pour l'avenir
Authors: Gaulme François 
Published: May 2011

Résumé Quel est l’état de la recherche sur l’Afrique en France ? Une volonté de renouveau traverse actuellement les milieux académiques africanistes, confrontés à un avenir incertain. Ce compte rendu donne à voir les débats engagés au cours du deuxième congrès des études africaines organisé à Bordeaux les 6, 7 et 8 septembre 2011. Cette grand-messe des africanistes témoigne de la vitalité des recherches africanistes et de l’affirmation de Bordeaux comme cœur des études africaines.
Culte du terrain à la rue Monsieur
Authors: Meimon Julien 
Published: May 2011

Résumé Du ministère de la France d’outre-mer au ministère de la Coopération, rupture ou continuité ? La transition postcoloniale de cette administration est lue à travers les trajectoires de carrière de ses fonctionnaires qui partagent tous le « culte du terrain » construit au cours de la période coloniale. Issus en majeure partie de l’Enfom et dotés d’une formation d’expert et de technicien, ils se méfient d’une bureaucratie administrative classique naissante qu’ils jugent trop éloignée des réalités de terrain.
L'aide néerlandaise en Afrique dans les années 1960
Authors: Dierikx Marc 
Published: May 2011

Résumé La signature du traité de Rome a conduit les Pays-Bas à participer à l’effort européen de coopération dans une région du monde qui leur était encore inconnue : l’Afrique. Conscient des limites des programmes européens et soucieux de faire valoir leurs intérêts propres, les Pays-Bas se désolidarisent en partie de la politique commune motivés par le soutien des intérêts de son secteur privé. À travers l’épopée de l’aide hollandaise en Afrique, cet article interroge la relation des intérêts nationaux avec les dispositifs d’aide de l’Europe.
Le « pauvre », l'aide et les politiques sociales
Authors: Morin Chloé 
Published: May 2011

Résumé L’aide au développement n’a pas seulement un impact sur les pays bénéficiaires : par rétroaction, elle influence les politiques publiques des pays donateurs. En Grande-Bretagne et en France, respectivement sous l’ère Blair et Jospin, elle a offert un réservoir d’idées mobilisé par les gouvernements pour leurs politiques domestiques. En suivant la « circulation des politiques publiques » au cours des vingt dernières années, on remarque que la notion de « pauvre », utilisée antérieurement pour les pays en voie de développement, inspire les politiques sociales élaborées à l’échelon national.
Incidence and Symptoms of High Altitude Illness in South Pole Workers: Antarctic Study of Altitude Physiology (ASAP)
Authors: Anderson Paul J. , Miller Andrew D. , O'malley Kathy A. , Ceridon Maile L. , Beck Kenneth C. , Wood Christina M. , Wiste Heather J. , Mueller Joshua J. , Johnson Jacob B. , Johnson Bruce D. 
Published: May 2011

Introduction Each year, the US Antarctic Program rapidly transports scientists and support personnel from sea level (SL) to the South Pole (SP, 2835 m) providing a unique natural laboratory to quantify the incidence of acute mountain sickness (AMS), patterns of altitude related symptoms and the field effectiveness of acetazolamide in a highly controlled setting. We hypothesized that the combination of rapid ascent (3 hr), accentuated hypobarism (relative to altitude), cold, and immediate exertion would increase altitude illness risk. Methods Medically screened adults (N = 246, age = 37 ± 11 yr, 30% female, BMI = 26 ± 4 kg/m2) were recruited. All underwent SL and SP physiological evaluation, completed Lake Louise symptom questionnaires (LLSQ, to define AMS), and answered additional symptom related questions (eg, exertional dyspnea, mental status, cough, edema and general health), during the 1st week at altitude. Acetazolamide, while not mandatory, was used by 40% of participants. Results At SP, the barometric pressure resulted in physiological altitudes that approached 3400 m, while T °C averaged -42, humidity 0.03%. Arterial oxygen saturation averaged 89% ± 3%. Overall, 52% developed LLSQ defined AMS. The most common symptoms reported were exertional dyspnea-(87%), sleeping difficulty-(74%), headache-(66%), fatigue-(65%), and dizziness/lightheadedness-(46%). Symptom severity peaked on days 1-2, yet in >20% exertional dyspnea, fatigue and sleep problems persisted through day 7. AMS incidence was similar between those using acetazolamide and those abstaining (51 vs. 52%, P = 0.87). Those who used acetazolamide tended to be older, have less altitude experience, worse symptoms on previous exposures, and less SP experience. Conclusion The incidence of AMS at SP tended to be higher than previously reports in other geographic locations at similar altitudes. Thus, the SP constitutes a more intense altitude exposure than might be expected considering physical altitude alone. Many symptoms persist, possibly due to extremely cold, arid conditions and the benefits of acetazolamide appeared negligible, though it may have prevented more severe symptoms in higher risk subjects.
Isoresonant Complex-valued Potentials and Symmetries
Authors: Autin Aymeric 
Published: May 2011

Abstract Let X be a connected Riemannian manifold such that the resolvent of the free Laplacian , has a meromorphic continuation through . The poles of this continuation are called resonances. When X has some symmetries, we construct complex-valued potentials, V, such that the resolvent of, which has also ameromorphic continuation, has the same resonances with multiplicities as the free Laplacian.
Hook-content Formulae for Symplectic and Orthogonal Tableaux
Authors: Campbell Peter S. , Stokke Anna 
Published: May 2011

AbstractBy considering the specialisation sλ(1, q, q2, … , qn–1) of the Schur function, Stanley was able to describe a formula for the number of semistandard Young tableaux of shape λ in terms of the contents and hook lengths of the boxes in the Young diagram. Using specialisations of symplectic and orthogonal Schur functions, we derive corresponding formulae, first given by El Samra and King, for the number of semistandard symplectic and orthogonal λ-tableaux.
Characterizations of Three Classes of Zero-Divisor Graphs
Authors: LaGrange John D. 
Published: May 2011

AbstractThe zero-divisor graph Γ(R) of a commutative ring R is the graph whose vertices consist of the nonzero zero-divisors of R such that distinct vertices x and y are adjacent if and only if xy = 0. In this paper, a characterization is provided for zero-divisor graphs of Boolean rings. Also, commutative rings R such that Γ(R) is isomorphic to the zero-divisor graph of a direct product of integral domains are classified, as well as those whose zero-divisor graphs are central vertex complete.
Chen Inequalities for Submanifolds of Real Space Forms with a Semi-Symmetric Non-Metric Connection
Authors: Özgür Cihan , Mihai Adela 
Published: May 2011

AbstractIn this paper we prove Chen inequalities for submanifolds of real space forms endowed with a semi-symmetric non-metric connection, i.e., relations between the mean curvature associated with a semi-symmetric non-metric connection, scalar and sectional curvatures, Ricci curvatures and the sectional curvature of the ambient space. The equality cases are considered.
The Nonrecurrent Laryngeal Nerve in Thyroid Surgery
Authors: Kraus Dennis , Shaha Ashok R , O'Neill James Paul , Femina Jennifer La 
Published: May 2011

ABSTRACT
A nonrecurrent laryngeal nerve is a rare anomaly and estimated to be present in 0.25 to 0.99% of patients.1 The identification and preservation of the recurrent laryngeal nerve is an essential part of thyroid surgery. It is now well-known that the recurrent laryngeal nerve is not only a single nerve but also a complex branching network of innervation. Thyroid surgery demands a precise understanding of the anatomical intimacy between the gland and surrounding structures, including the parathyroid glands and neurovascular tissue. The morbidity associated with thyroid surgery, in the short-term, generally relates to hematoma collection and hypocalcemia. Long-term morbidity is more commonly seen with dysphonia and vocal cord dysfunction due to superior laryngeal nerve damage and its role in explosive sound formation, the recurrent laryngeal nerve, its tortuous anatomical course, and its role in laryngeal musculature innervation.
We review the literature on this subject and report three cases of the rare nonrecurrent anomaly, firstly a 75-year-old lady with a large retrosternal goiter. During her initial work-up which included a CT scan of the thorax, an ‘arteria lusoria' was identified in the retroesophageal plane. Intraoperatively, a right-sided nonrecurrent inferior laryngeal nerve (NRILN) was identified. The second case is of a 63-year-old lady with a right-sided type 1 nonrecurrent laryngeal nerve which we identified and photographed when medially retracting the gland off the central compartment and ligament of Berry. The third case is that of a 45-year-old lady with a right-sided thyroid nodule and a right-sided NRILN identified intraoperatively.
What is the Ideal CO2 Insufflation Pressure for Endoscopic Thyroidectomy? Personal Experience with Five Cases of Goiter
Authors: PRK Bhargav , A Kusumanjali , R Nagaraju , V Amar 
Published: May 2011

ABSTRACT

Introduction
The endoscopic thyroidectomy (ET) using high CO2 insufflation pressures (CIP) are prone to complications, such as hypercarbia, acidosis, pneumomediastinum and cardiac arrhythmias. The purpose of this study was to analyse the perioperative events and CO2 related morbidity in five cases of endoscopic thyroidectomy in our experience.

Methods
Between Febraury 2010 and August 2010 (6 months), five cases of benign goiters operated with extracervical ET technique in endocrine surgery department of a teritiary care hospital of southern India were studied. Clinicopathological, operative and morbidity data were documented and analyzed.

Results
All the five patients were women and mean age was 37.2 years (25-46). CIP of 12 to 14 mm Hg was used for creation of working space and CIP of 8 to 10 mm Hg for its maintainence. Average operative time was 135 minutes (65-212). Two cases had to be converted into open procedure due to gas related complications, such as hypercarbia, acidosis and ventricular tachycardia.

Conclusions
CO2 insufflation pressure (CIP) of 10 to 12 mm Hg for creation of working space and 6 to 8 mm Hg for maintainence of space is optimal. A protocol based on CIP, monitoring and intermittent desufflation is recommended for safe ET with minimum complications.
Hypocalcemia and Hoarseness Following Total Thyroidectomy for Benign Disease: Relationship of Incidence to the Size of the Gland
Authors: Fernando R , Chandrasinghe PC , Bandara M 
Published: May 2011

ABSTRACT

Introduction
Total thyroidectomy is considered as the standard surgical procedure for most malignancies and benign disease involving both lobes of the thyroid gland. Postoperative complications are likely to be commoner when the thyroid gland is large in size due to the alteration of structural anatomy.

Methods
Postoperative complications of 102 patients who underwent total thyroidectomy for benign disease, by the same surgeon, were analyzed. Patients were prospectively followed up and presence of hoarseness and hypocalcemia, both transient and temporary, were compared with the weight of the gland.

Results
Fourteen patients developed hypocalcemia of which 12 (11.7%) had transient and 2 (1.96%) had permanent deficiencies. Eight patients developed hoarseness following surgery of which seven (6.86%) had transient and only one (0.98%) had permanent hoarseness. A mean thyroid weight of 91.78 gm was observed in the uncomplicated group. Those who developed postoperative hypocalcemia and transient hoarseness had a mean thyroid weight over 100 gm. One patient, who had a thyroid weighing 195 gm developed permanent hoarseness due to RLN injury.

Conclusion
There is no statistically significant difference in the incidence of transient RLN and transient or permanent hypocalcemia. With increased size of the thyroid gland increased rate of complications was observed with a mean thyroid weight above 100 gm. There may be a significant risk of permanent RLN injury when the thyroid gland is enlarged over 10 times (closer to 200 gm) its normal size.
Decision Making in Lateral Skull Base Surgery
Authors: Sankhla Suresh , Morwani KP , Agrawal Rahul , Jayashankar Narayan 
Published: May 2011

ABSTRACTLateral skull base surgery encompasses a number of lesions and also a variety of approaches to deal with them. Correct understanding of the nature of the lesion as also various patient factors are used to decide on surgical option wherever indicated. The extent of the lesion and also the involvement of structures adjacent to the lesion is discussed with the neuroradiology team, and is very important in deciding the most favorable surgical approach. The subject is explained preoperatively about staging of the procedure, if needed. The principle is to gain maximal exposure of the lesion with good control of the neurovascular structures along the surgical route, so as to minimize morbidity. Correct decision making and good skill help in achieving the best possible results.
Management of Vestibular Schwannoma: Dependence on Stakeholder's View for Small and Medium-Sized Tumors
Authors: Zisiopoulou Maria , Gouveris Haralampos , Mann Wolf J 
Published: May 2011

ABSTRACTManagement options for patients with vestibular schwannoma include observation and active treatment, namely surgical resection, gamma knife stereotactic radiosurgery or fractionated radiation therapy. Although for large tumors microsurgery remains the mainstay of treatment, management of the small- and medium-sized vestibular schwannomas has been the matter of considerable controversy. Computerized clinical decision support systems have been developed to assist clinicians in this demanding task. Nonetheless, the complexity of the problem requires adaptation of the decision strategy to specific circumstances arising within a particular clinical scenario which can not always be modeled with adequate precision or addressed adequately within a mathematical framework. We present a set of clinical, neurophysiologic and radiologic parameters and the respective evidence which may guide carers’ decisions. These parameters include the size, growth rate and localization of the tumor, the age, general medical condition, facial nerve function, hearing and hearing deterioration rate, balance, vestibular and trigeminal nerve function of the affected individual, the estimated risk of malignant transformation and radiation-induced tumors, the health-related quality of life measures, the patient's and surgeon's preference and the issue of cost-effectiveness. A complex decision analysis, guided by evidence and tailored to each individual patient is required.
Jugular Foramen Tumors
Authors: Rayappa C 
Published: May 2011

ABSTRACTJugular foramen tumors are rare cranial base lesions that present diagnostic and management difficulties. Paragangliomas were the most frequent lesions, followed by schwannomas and meningiomas. These tumors have characteristic radiological features. Radical resection of these tumors with preservation of the lower cranial nerves is the treatment of choice. Despite the advances in skull base surgery, new postoperative lower cranial nerve deficits still represent a challenge.
The Role of Radiotherapy in the Management of Paraganglioma
Authors: Trombetta Mark 
Published: May 2011

ABSTRACTParagangliomas or glomus tumors are usually low-grade hypervascular tumors occurring in various sites of the autonomic nervous system including the carotid body, glomus vagale and glomus tympanicum. Although the grading of the tumor suggests a benign clinical course, the tumor can be locally malignant and surgical management is sometimes difficult because of postoperative functional loss and local recurrence. In addition, the operative field is generally very bloody and tissue planes are not always well-defined.Though the optimal management of paraganglioma occurs in a multidisciplinary setting, considering the excellent local control rates with primary irradiation alone, a nonsurgical definitive approach should initially be considered.
Transmastoid Repair of Temporal Meningoencephaloceles and Cerebrospinal Fluid Otorrhea
Authors: Garavello Werner , Gaini Lorenzo , Zanetti Diego 
Published: May 2011

ABSTRACTThis paper reviews the diagnosis and treatment of temporal bone meningoencephaloceles, defined as the herniation of meninges or brain tissue into empty spaces within the temporal bone, i.e. tympanic or mastoid cavity, through the tegmen tympani or antri respectively. It also describes the current methods of control of cerebrospinal fluid (CSF) leaks, which commonly present as serous otorrhea or rhinorrhea in addition to a variety of symptoms, such as conductive hearing loss. Imaging is the mainstay of the diagnostic process. Management of the condition is surgical, and this review outlines the surgical options with special emphasis on the transmastoid approach and the materials applicable for repair of the bony dehiscences.
MRI of Lateral Skull Base Lesions
Authors: Patkar Deepak P , Yanamandala Rama , Pardhi Mukesh , Pungavkar Sona A , Gaikwad Vishal , Pawar Sudarshan Vijay 
Published: May 2011

ABSTRACT
This article reviews the role of magnetic resonance imaging (MRI) in the evaluation of lateral skull base lesions. Due to superior soft tissue resolution and multiplanar capability, MRI provides accurate information and exquisite anatomical detail. Thus, it guides the surgeon in proper preoperative planning regarding the approach of a lesion. MRI is also useful in post-treatment follow-up to assess the therapeutic response and to identify potential complications. We discuss the relevant anatomy, indications of MRI and MR pulse sequences used in the diagnosis of lesions of lateral skull base. Characteristic MRI findings of various lesions which help to arrive at a specific diagnosis as well as pitfalls of MRI which may confound the diagnosis are described. Newer MR pulse sequences enable image-guided surgery, which assist the surgeon intraoperatively, are briefly discussed. In summary, this article emphasizes the role of MRI in providing a specific answer to a clinical problem and its ability to guide the clinician for better management of patients.
Gamma Knife Radiosurgery for Vestibular Schwannomas
Authors: Liscak Roman 
Published: May 2011

ABSTRACTThe current gamma knife radiosurgery technique involves the use of magnetic resonance imaging for targeting, the application of a low marginal dose (usually between 12 and 13 Gy) and highly conformal treatment planning using multiple small isocenters. This technique achieves an average tumor control rate of 95% and open surgery is needed in fewer than 2 to 3% of patients treated by gamma knife. Facial nerve function preservation is achieved in up to 99% of cases and chance of preserving serviceable hearing is usually between a 70 to 80%. The introduction of ventriculoperitoneal drainage after radiosurgery is required for 1 to 8% of patients. Gamma knife radiosurgery can be treatment of choice for the patients, where the diameter of the tumor is less than 3 cm.
Avoidance of Facial Nerve Injury in Lateral Skull Base Surgery
Authors: Sughrue Michael E 
Published: May 2011

ABSTRACTIn the radiosurgery era, the treatment strategies for vestibular schwannoma have changed at most centers. This new paradigm holds that rational CPA tumor therapy requires balancing often competing goals of therapy, and the associated risks and benefits of different therapies or combination of therapies. The present review discusses this new paradigm and its specific implications for CPA tumor surgery. Inevitably, such a review will focus largely on minimizing facial nerve morbidity, as this is both the most modifiable risk, and the risk that is most reduced with the use of adjuvant therapies, such as stereotactic radiosurgery (like Gamma knife). The facts about facial nerve preservation in CPA tumor surgery will be reviewed, and methods for avoiding facial nerve morbidity will be discussed.
Should Gamma Knife be Offered as a Primary Treatment for a Resectable Glomus Jugulare Tumor?
Authors: Sankhla Suresh , Morwani KP , Jayashankar Narayan 
Published: May 2011

ABSTRACTAttempted total resections is the preferred treatment option in the management of glomus jugulare tumors in most subjects. In the elderly patients, it may be advisable to leave a tiny residue over the involved cranial nerve to preserve function. In a medically unfit and anesthetically high-risk subject observation with serial MRI scans is the preferred line of management. If in such a patient there occurs brainstem compression, it is prudent to only operate the intracranial part to relieve the compression explaining the very high-risk in this group. Radiotherapy is not to be offered as a primary treatment for glomus jugulare tumors.
Fetal and Gynecological 3D Ultrasound in Daily Practice
Authors: Baba Kazunori 
Published: May 2011

ABSTRACT
Three-dimensional ultrasound has many functions, and is a little complicated to use perfectly. But by starting from easy cases, objects and display modes in daily practice, 3D ultrasound would be a powerful diagnostic tool when and after some abnormalities are suspected with 2D ultrasound. Some tips to use 3D ultrasound easily and efficiently are demonstrated for those who are not familiar with 3D ultrasound.