bluuebunny/crossref_metadata_2025_split huggingface dataset:
Energy splitting of eg orbitals in Fe‐doped bilayer manganites
Authors: Ma Xiao , Kou Zhiqi , Di Naili , Cheng Zhaohua , Li Qing'An 
Published: October 2004

Abstract57Fe Mössbauer spectra measurements of Fe‐doped La2–2xSr1+2xMn1.88Fe0.12O7 (x = 0.30, 0.40, and 0.55) compounds were employed to estimate the energy splitting of the Mn3+ ion eg orbital. A large splitting energy ES, about 1.0 eV, was found for each sample. This suggests that there is a strong electron localization effect in these Fe‐doped bilayer manganites. The transport behaviour can be explained on the basis of the effect of ES on the hopping possibility of Mn3+ eg electrons. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dielectric properties of compositionally graded Ba1–xSrxTiO3 thin films described by the transverse‐field Ising model
Authors: Gao Y. H. , Cao H. X. , Jiang Q. 
Published: October 2004

AbstractThis investigation reports on the phase transition and dielectric properties of compositionally graded Ba1–xSrxTiO3 (BST) thin films with x decreasing from 0.20 to 0.10 in successive slabs, based on the transverse‐field Ising model (TIM) within the framework of mean field theory. The random bond model of related parameters is applied to mimic doping. The effect on polarization and dielectric susceptibility arising from a gradient in composition is taken into account. The peaks of dielectric susceptibility versus temperature become comparatively flat by modulating appropriate thickness in each slab in compositionally graded BST thin films, which means that the thickness may weaken the effect of composition gradient. When increasing the number of slabs of thin films, the dielectric susceptibility shows good temperature stability in a wide temperature range, which is useful for reducing the temperature coefficient of dielectric susceptibility without depressors. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Compton profile study of polycrystalline ytterbium
Authors: Ahuja B. L. , Sharma M. 
Published: October 2004

AbstractIn this paper, we present the first experimental Compton profile of ytterbium. Measurement has been made, at an intermediate resolution (0.40 a.u.), using gamma‐ray Compton spectrometry employing a 20 Ci 137Cs source. In the absence of band‐structure calculations, the experimental profile is compared with a free‐electron model‐based profile and renormalised free‐atom (RFA) model. It is seen that the RFA results are comparatively in better agreement with the experiment. Using our Compton profile measurement, we have also derived the cohesive energy of ytterbium. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Continuous flow 2H/1H and 18O/16O analysis of water samples with dual inlet precision
Authors: Gehre M. , Geilmann H. , Richter J. , Werner R. A. , Brand W. A. 
Published: October 2004

AbstractA method for isotope ratio analysis of water samples is described comprising an on‐line high‐temperature reduction technique in a helium carrier gas. Using a gas‐tight syringe, injection of 0.5 to 1 μL sample is made through a heated septum into a glassy carbon reactor at temperatures in excess of 1300°C. More than 150 injections can be made per day and both isotope ratios of interest, δ2H and δ18O, can be measured with the same setup. The technique has the capability to transfer high‐precision stable isotope ratio analysis of water samples from a specialized to a routine laboratory task compatible with other common techniques (automated injection for GC, LC, etc.). Experiments with an emphasis on the reactor design were made in two different laboratories using two different commercially available high‐temperature elemental analyser (EA) systems.In the Jena TC/EA unit, sample‐to‐sample memory (single injection) has been reduced to ∼1% and high precision of about 0.1‰ for δ18O and < 1‰ for δ2H has been achieved by a redesign of the glassy carbon reactor and by redirecting the gas flow of the commercial TC/EA unit. With the modified reactor, the contact of water vapour with surfaces other than glassy carbon is avoided completely. The carrier gas is introduced at the bottom of the reactor thereby flushing the outer tube compartment of the tube‐in‐tube assembly before entering the active heart of the reactor.With the Leipzig high‐temperature reactor (HTP) similar precision was obtained with a minor modification (electropolishing) of the injector metal sleeve. With this system, the temperature dependence of the reaction has been studied between 1100 and 1450°C. Complete yield and constant isotope ratio information has been observed only for temperatures above 1325°C. For temperatures above 1300°C the reactor produces an increasing amount of CO background from reaction of glass carbon with the ceramic tube. This limits the usable temperature to a maximum of 1450°C. Relevant gas permeation through the Al2O3 walls has not been detected up to 1600°C. Copyright © 2004 John Wiley & Sons, Ltd.
Development of a compound‐specific isotope analysis method for acetone via 2,4‐dinitrophenylhydrazine derivatization
Authors: Wen Sheng , Feng Yanli , Wang Xinming , Sheng Guoying , Fu Jiamo , Bi Xinhui 
Published: October 2004

AbstractA novel method has been developed for compound‐specific isotope analysis for acetone via DNPH (2,4‐dinitrophenylhydrazine) derivatization together with combined gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). Acetone reagents were used to assess δ13C fractionation during the DNPH derivatization process. Reduplicate δ13C analyses were designed to evaluate the reproducibility of the derivatization, with an average error (1 standard deviation) of 0.17 ± 0.05‰, and average analytical error of 0.28 ± 0.09‰. The derivatization process introduces no isotopic fractionation for acetone (the average difference between the predicted and analytical δ13C values was 0.09 ± 0.20‰, within the precision limits of the GC/C/IRMS measurements), which permits computation of the δ13C values for the original underivatized acetone through a mass balance equation. Together with further studies of the carbon isotopic effect during the atmospheric acetone‐sampling procedure, it will be possible to use DNPH derivatization for carbon isotope analysis of atmospheric acetone. Copyright © 2004 John Wiley & Sons, Ltd.
Opioid use in the elderly
Authors: Wilder‐Smith Oliver H.G. 
Published: October 2004

AbstractPain treatment in the elderly is an important challenge to Western societies due to increasing numbers of old persons, their higher incidence of pain, and their greater susceptibility to adverse effects of pain medication. We provide an overview of the factors liable to influence opioid action in the elderly population.A major challenge for the physician prescribing opioids in the elderly is their greater risk of medication‐associated problems. Thus, older patients suffer increased vulnerability to adverse drug effects and interactions, higher rates of polypharmacy, and more comorbidity. These problems are compounded by a relative lack of definitive published information. There is clearly a need for more research in this area.Aging affects opioid pharmacokinetics via altered body composition (distribution volumes) and organ function (liver = metabolism, kidney = excretion). Pharmacodynamics is affected via impaired neurotransmitter/peptide production and changed receptor affinities/populations. Older women may need less morphine analgesia postoperatively, while pain sensitivity tends to increase particularly in older men. However, the net effects of changes in opioid pharmacology with age on clinical opioid analgesia remain unclear, probably due to the significantly greater variability in body function with increasing age.Practical recommendations for opioid prescription in the elderly include meticulous review of indication for opioid use, not only initially but also at regular intervals thereafter. A policy of careful titration should be followed, with conservative choice of dosage on starting. Dosing intervals may need to be lengthened subsequently. Finally, it should be remembered that old persons do not necessarily need less opioid than younger ones.
Impact of present and past antipsychotic side effects on attitude toward typical antipsychotic treatment and adherence
Authors: Lambert M. , Conus P. , Eide P. , Mass R. , Karow A. , Moritz S. , Golks D. , Naber D. 
Published: October 2004

AbstractObjective(1) determine which antipsychotic side effects (SE) schizophrenic patients consider the most distressing during treatment with typical antipsychotics, (2) measure the impact of actual and past SE on patients' attitude toward antipsychotics and (3) assess the influence of both on adherence.MethodsThe 213 schizophrenics, treated with conventional antipsychotics, were recruited in two psychiatric hospitals in Hamburg. Subjects were assessed about type and severity of present and past side effects and their attitude and adherence to antipsychotic treatment.ResultsThe 82 (39%) patients presented present SE while 131 (61%) did not. Sexual dysfunctions (P<0.001), extrapyramidal (P<0.05) and psychic side effects (P<0.05) were rated as significantly subjectively more distressing than sedation or vegetative side effects. Patients presenting with present SE compared with patients without present SE had a significantly more negative general attitude toward antipsychotics (P<0.05), were more doubtful about their efficacy (P<0.01) and were less likely to encourage a relative to take such a medication in case of need (P<0.001). A regression analysis indicated that nonadherence was mainly influenced by negative general and efficacy attitudes toward antipsychotics and the experience of past or present antipsychotic side effects.ConclusionsAll antipsychotic side effects, present or past, can have a durable negative impact on patient's attitude toward antipsychotic treatment and adherence. Non-adherence is mainly determined, among other factors, by these negative attitudes, which are partly influenced by the experience of past or present antipsychotic-induced side effects.
Salivary Epidermal Growth Factor Concentration in Adults with Reflux Laryngitis
Authors: Eckley Claudia A. , Michelsohn Nelson , Rizzo Luiz Vicente , Tadakoro Carlos Eduardo , Costa Henrique O. 
Published: October 2004

OBJECTIVEThe mechanisms involved in the muco‐sal alterations of laryngopharyngeal reflux (LPR) have not been well established. Reports indicate a decrease in the salivary epidermal growth factor (EGF) of patients with reflux esophagitis, but there are no reports of its behavior in LPR. Our objective was to determine the salivary concentration of EGF in adults with LPR.STUDY DESIGN AND SETTINGSalivary EGF concentration of 26 patients with LPR and 20 healthy controls was determined using a commercially available ELISA kit. Patients with LPR were graded according to endoscopic and laryngoscopic criteria.RESULTSSalivary EGF concentration was significantly lower in the LPR group when compared with controls (P = 0.002). No correlation between the severity of laryngeal findings or esophagitis and salivary EGF concentration could be determined.CONCLUSIONSThe decreased salivary concentration of EGF in adults with LPR suggests that a deficiency in this polypeptide could be associated to the disease.
Incidence of Dehiscence of the Facial Nerve at Surgery for Middle Ear Cholesteatoma
Authors: Lin Jen‐Chih , Ho Kuen‐Yao , Kuo Wen‐Rei , Wang Ling‐Feng , Chai Chee‐Yin , Tsai Shih‐Meng 
Published: October 2004

OBJECTIVETo identify the incidence of dehiscence of the facial nerve in patients undergoing surgery for cholesteatoma and to describe its relevance with iatrogenic facial nerve injury.STUDY DESIGN AND SETTINGThis was a retrospective study including 117 tympanoplasties with or without mastoidectomy performed in 49 men and 66 women.RESULTSThe presences of FND after exenteration of disease are 33.3% of total surgical procedures, 33% of the initial procedures, and 37.5% of the revision procedures. The locations of facial nerve dehiscence were 87.2% in only the tympanic segment, 7.7% in only the vertical segment, and 5.1% in both the tympanic and vertical segments.CONCLUSIONS AND SIGNIFICANCEThe incidence of facial nerve dehiscence is high (33.3%) in our study. The surgeon should keep in mind that the location of facial nerve dehiscence with cholesteatoma is comparable with the most common area of iatrogenic facial nerve injury during otologic surgery.
How Do Cartilage and other Material Overlay over a Prosthesis Affect its Vibration Transmission Properties in Ossiculoplasty?
Authors: Morris David P. , Bance Manohar , Van Wijhe Rene G. 
Published: October 2004

OBJECTIVEThe prosthesis/eardrum interface is often deliberately modified by cartilage overlay, or by soft tissue in‐growth. We examined the effects of vibration transmission to the footplate of inserting cartilage of varying sizes, and materials of varying rigidities.STUDY DESIGN AND SETTINGUsing fresh human cadaveric temporal bones, stapes vibrations were measured. A partial ossicular reconstruction prosthesis was covered with differing materials and cartilage sizes. Materials used included glass (rigid), cartilage (intermediate), and Merocel® (soft). Cartilage sizes varied in size relative to the prosthesis head.RESULTSRigidity of material had little impact. Cartilage size had an impact, with smaller cartilage covers performing best.CONCLUSIONLarger cartilage sizes performed worse. This could be a result of increased tension on the eardrum from larger cartilage size. There is little impact stiffness of interposed material stiffness.SIGNIFICANCECartilage of the size used clinically has little impact on vibration transmission to the footplate. A wide range of materials could clinically be interposed over the prosthesis.
Cyclin D1, p53, MIB1, Intratumoral Microvessel Density, and Human Papillomavirus in Advanced Laryngeal Carcinoma: Association with Nodal Metastasis
Authors: Kumar Rekha V. , Shenoy Ashok M. , Daniel Richard , Shah Keerti V. 
Published: October 2004

OBJECTIVEWe sought to study various parameters in laryngeal squamous cell carcinoma (LSCC) that might predict nodal metastasis.STUDY DESIGN AND SETTINGSixty‐four LSCCs were examined with respect to their histopathology and, using immunohistochemistry, their proliferative capacity (MIB1), p53 and cyclin D1 status, and intratumoral microvessel density. The presence of human papillomavirus was ascertained by the polymerase chain reaction.RESULTSHistopathologically, most tumors had an infiltrating/mixed growth pattern and a diminished inflammatory reaction at the growing margin. In addition, 56% of the tumors were positive for MIB1, with 64% showing p53 overexpression; 70% were positive for cyclin D1; and 59% showed increased tumor microvessel density. Of 42 cases analyzed, 9.5% were positive for human papillomavirus 16.CONCLUSIONSOf the parameters studied, a diminished lymphocytic inflammatory response at the periphery (P < 0.05) and cyclin D1 overexpression (P < 0.001) correlated significantly with cervical nodal metastasis at presentation.SIGNIFICANCECyclin D1 overexpression, easily assessed on biopsy samples, may thus help in optimizing therapy at the outset.
A Simplified Technique for Airway Correction at the Nasal Valve Area
Authors: Friedman Michael , Ibrahim Hani , Lee George , Joseph Ninos J. 
Published: October 2004

OBJECTIVETo describe a simplified system to correct an obstructed nasal airway utilizing the Mitek bone anchor suspension technique (BAST).STUDY DESIGNThis is a retrospective/prospective study of patients with nasal airway obstruction treated with the BAST. The retrospective study is based on 188 patients who underwent the BAST over the past 5 years and were analyzed to assess complications and subjective results. The prospective group consisted of 52 patients with unilateral or bilateral valve obstruction who were assessed with preoperative and postoperative rhinomanometry and quality of life (QOL) questionnaires.METHODSThe surgical technique is based on introducing a bone anchor into the orbital rim through a 4‐mm stab incision. The bone anchor system comes with attached sutures that are easily passed to the valve area and secured in position to support and open the valve area. Preoperative and postoperative QOL surveys and rhinometric studies were compared in 52 patients to assess the subjective and objective outcomes of the procedure.RESULTSBased on subjective data, over 90% of the patients had significant improvement in their nasal airway. Objectively, cross‐sectional areas at the nasal valve were found to have significantly improved postoperatively (P < 0.046). Complications were rare and limited to localized infection, reaction to sutures, and loss of support.CONCLUSIONCorrection of nasal valve obstruction with this technique provides a simplified alternative in selected patients to improve airflow and decrease nasal resistance. The BAST allows for a simple, highly effective correction of an obstructed airway with minimal complications.
Transnasal Endoscopic Repair of Choanal Atresia: Why Stent?
Authors: Schoem Scott R. 
Published: October 2004

OBJECTIVETo analyze the outcome of transnasal endoscopic repair of choanal atresia in children without stenting.DESIGNRetrospective review.SETTINGAcademic pediatric referral center.PATIENTSThirteen children ages 2 days to 13 years old (mean 45 months) who presented with unilateral (8) or bilateral (5) choanal atresia and underwent transnasal endoscopic surgery between January 1997 and May 2002. No stents were used. All patients received combinations of oral steroids, topical nasal steroids, and oral antibiotics. Patency was defined as less than 50% restenosis.RESULTSThe 4 patients who underwent office serial examination alone after surgery remained patent. Seven of the 9 patients who underwent reexamination under general anesthesia had varying amounts of emerging granulation tissue or minor synechia formation that resolved with microdebrider excision. All serial office endoscopies demonstrated no restenoses. No office dilations were performed. There were no long‐term complications. One patient (2 days old) who underwent tracheoesopha‐geal fistula repair and bilateral choanal atresia repair on the same day required a blood transfusion. Both patients with tracheostomies were decannu‐lated.CONCLUSIONSTransnasal endoscopic repair of choanal atresia, both unilateral and bilateral, is safe, and is effective without stenting. Postoperative failure of endoscopic approaches may be a result of prolonged mucosal trauma from stenting rather than any deficiency inherent in the surgical technique. Adjuctive therapy may not offer any advantage in promoting patency.
Proton Pump Inhibitor Therapy for Chronic Laryngo‐Pharyngitis: A Randomized Placebo‐Control Trial
Authors: Steward David L. , Wilson Keith M. , Kelly Dan H. , Patil Mona S. , Schwartzbauer Heather R. , Long John D. , Welge Jeff A. 
Published: October 2004

OBJECTIVETo determine the efficacy of proton‐pump inhibitor (PPI) therapy for chronic laryngo‐pharyngitis treated with lifestyle modification.STUDY DESIGN AND METHODSDouble‐blind, randomized trial comparing two‐month Rabeprazole (20 mg b.i.d.) to placebo control.RESULTSCompared to baseline, both PPI and control patients had significant improvement in total reflux symptoms (P = 0.002 and P = 0.03 respectively), with significant improvement in “laryngo‐pharyngeal” but not “typical” reflux symptoms. No significant difference was noted for change in reflux symptoms between PPI‐treated and control patients (P = 0.44). Significant global improvement was noted by 50% of control and 53% of PPI‐treated patients (P = 1.0). No significant differences were noted within or between treatment groups for change in health status or videostrobolaryngoscopy grade. Lifestyle modification compliance correlated significantly with global improvement.CONCLUSIONCompared to baseline, lifestyle modification for 2 months significantly improved chronic laryngo‐pharyngitis symptoms. When compared to control, treatment with a PPI failed to demonstrate significantly greater improvement in reflux symptoms, health status, or laryngeal appearance.
The Role of Agger Nasi Air Cells in Patients Requiring Revision Endoscopic Frontal Sinus Surgery
Authors: Bradley Dewayne T. , Kountakis Stilianos E. 
Published: October 2004

OBJECTIVESTo determine the association of agger nasi air cell disease with frontal rhinosinusitis, assessed by computed tomography (CT), in patients who require revision functional endoscopic sinus surgery (FESS).METHODSWe prospectively collected data on patients undergoing revision FESS at a tertiary care medical center over an 18‐month period. Sinus CT scans were graded as per Lund‐Mackay. Frontal sinus findings on CT scan were correlated with the presence or absence of disease in agger nasi air cells.RESULTSEighty patients underwent revision FESS in an 18‐month period. A total of 160 sides were evaluated by sinus CT scan with agger nasi being present in all but 11 sides (93%). One patient did not have a pneumatized frontal sinus on 1 side and so 148 sides were available for study. Frontal sinus disease was present in 119 and absent in 29 sides. The average CT grade of patients with frontal rhinosinusitis was 8.4 while it was only 3.0 in patients without frontal rhinosinusitis (P = 0.000). Agger nasi air cell disease was present in only 3 of 29 (10%) sides in patients without frontal rhinosinusitis and was present in all 119 (100%) sides of patients with frontal rhinosinusitis (P = 0.0000).CONCLUSIONAgger nasi air cells are a common anatomic feature, present in 93% of our patients. Agger nasi air cell disease correlates strongly with frontal sinus disease as assessed by sinus CT scan in patients undergoing revision FESS. In addition, frontal sinus disease correlates with the severity of overall sinus disease as determined by sinus CT scan.
Functional Surgical Approach to the Level I for Staging Early Carcinoma of the Lower Lip
Authors: Guney E. , Yigitbasi O. G. 
Published: October 2004

OBJECTIVEThe management of the neck in patients with T1‐T2 carcinoma of the lower lip (LLC) remains controversial. Suprahyoid neck dissection seems a reliable diagnostic approach, although it sacrifices the submandibular gland and its vascularity.STUDY DESIGN AND SETTINGThis study was a prospective, randomized study. Patients with previously untreated T1 or T2 primary LLC underwent either classical suprahyoid neck dissection (CSHD) or functional suprahyoid neck dissection (FSHD) in continuity with the resection of the cancer of the lip.RESULTSA total of 48 suprahyoid neck dissections were performed in 36 patients. Among these dissections, 27 were CSHD and 21 were FSHD. The average number of dissected lymph nodes was similar for both classical and functional type operations. The overall follow‐up period was 40.5 months.CONCLUSIONSThe end result of this series supports the idea that FSHD is a reliable diagnostic method for the management of level I lymph nodes in LLC. FSHD can avoid undertreatment or overtreatment of the patients with early LLC while preserving the submandibular gland.