bluuebunny/crossref_metadata_2025_split huggingface dataset:
An approximation algorithm for state minimization in 2-MDFAs
Authors: Subramani K. , Tauras C. 
Published: August 2006

Abstract

In this paper, we analyze the problem of state minimization in a class of Finite State Automata called Two Start State Deterministic Finite State Automata (2-MDFAs). A 2-MDFA is similar to a deterministic finite state automaton (DFA), in that on a given input, each state has precisely one destination state; however, it differs from a DFA in that there are two start states.
A string is accepted by a 2-MDFA if and only if there exists a transitional path from either start state to a finish state, on that string
. Observe that 2-MDFAs provide a limited amount of non-determinism and hence investigating their properties from the perspective of state minimization is a worthwhile pursuit. In case of unbounded non-determinism, i.e., Non-deterministic finite state automata (NFAs), it is well-known that the state minimization problem is PSPACE-complete [Jiang and Ravikumar in Proceedings of the 18th International Colloquium on Automata, Languages and Programming, ICALP’91, Madrid, Spain, July 8–12, 1991] and further that such automata can be exponentially more succinct than DFAs [Meyer and Fischer in Proceedings of the 12th SWAT(Annual Symposium on switching and automata theory), pp 188-191, 1971]. Even in the case of 2-MDFAs, the minimization problem remains non-trivial; indeed, Malcher in Theor Comput Sci 327(3):375–390, 2004 shows that the corresponding decision problem is NP-complete. We focus on deriving approximability bounds for the state minimization problem in 2-MDFAs. Our main contribution in the current paper, is the design of an
n
-approximation algorithm for state minimization in 2-MDFAs, where
n
denotes the minimum number of states required to represent the input language as a 2-MDFA. We also present a proof that this bound is tight for our algorithm.
Spatial pattern analysis in forest dynamics: deviation from power law and direction of regeneration waves
Authors: Schlicht Robert , Iwasa Yoh 
Published: August 2006

AbstractGrid‐based models have been used to understand spatial heterogeneity of the vegetation height in forests and to analyze spatio‐temporal dynamics of the forest regeneration process. In this report, we present two methods of identifying lattice models when spatio‐temporal data are given. The first method detects directionality of regeneration waves based on the timing of local disturbance events. The second evaluates the forest pattern by recording the fraction of high and low vegetation areas at multiple spatial scales. We illustrate these methods by applying them to patterns generated using three simple stochastic lattice models: (1) two‐state model, distinguishing sites with high and low vegetation, (2) three‐state model, in which sites can be in an additional disturbed state, and (3) Shimagare model, which considers a continuous range of states. The combination of the two methods provides efficient means of distinguishing the models. The first method has a more direct ecological meaning, while the second is useful when forest data are limited in time.
Factors determining plant–neighbour interactions on different spatial scales in young species‐rich grassland communities
Authors: Milbau Ann , Reheul Dirk , De Cauwer Benny , Nijs Ivan 
Published: August 2006

AbstractIn naturally colonised species‐rich grassland communities, we examined the properties of a plant's aboveground neighbourhood that affect its performance (aboveground biomass). To this end a range of neighbourhood parameters were measured: number, biomass and species richness of the neighbours, number and biomass of the conspecific neighbours, and light availability at the base of the target plant. We also determined at which neighbourhood size the strongest target plant–neighbour interactions occurred, and whether conspecific neighbours affected competitively stronger or weaker target species differently. Target plant performance varied with target identity, and was significantly affected by light availability and the number of neighbouring plants (neighbourhood density). Depending on the target species, there was also an effect of total neighbour biomass on plant performance. The target plants were most strongly affected by their neighbours within a 3‐cm distance, which could account for 78% of the variance in target biomass. Number or biomass of the conspecific neighbours did not contribute to the explanation of target performance in any of the target species. Whereas in an 8‐cm neighbourhood the amount of light penetration was the strongest predictor of target performance, the number of neighbours was more important in a 3‐cm neighbourhood. These experimental results might be useful to extend existing neighbourhood competition models for one or two species to multi‐species competition models.
Assessment of left ventricular asynchrony using volume—time curves of 16 segments by real‐time 3 dimensional echocardiography: Comparison with tissue Doppler imaging
Authors: Park Seong‐Mi , Kim Ki‐Chang , Jeon Min‐Jae , Lee Chang‐Kun , Kim Dae‐Hyeok , Park Keum‐Soo , Lee Woo‐Hyung , Kwan Jun 
Published: August 2006

AbstractBackground:Recent technical developments with high‐resolution real‐time 3 dimensional echocardiography (RT3DE) facilitate the acquisition of high quality images and the analysis of segmental volume—time curves (VTCs).Aims:To assess left ventricular (LV) asynchrony using the VTCs of 16 segments by RT3DE, and to evaluate accuracy compared to tissue Doppler imaging (TDI).Methods:Twenty‐three heart failure (HF) patients (LVEF: 25±6%, age: 60±13 years) and 16 normal controls underwent TDI and RT3DE. The standard deviation (SD3) of the end systolic time reaching minimal systolic volume for the 16 segments on VTCs was obtained by RT3DE. The standard deviation (SD2) of the electromechanical coupling time for the 8 segments was measured using TDI.Results:SD3 was markedly higher in HF patients than in controls (7.7±2.5 vs 1.5±1.0%, P<0.01) and increased as LVEF decreased (r=−0.85, P<0.01). SD2 was also significantly higher in HF patients (27.0±8.6 vs 12.6±5.0 ms, P<0.01) and had a good negative correlation with LVEF (r=−0.72, P<0.01). SD3 was well correlated to SD2 (r=0.66, P<0.01).Conclusions:We suggest that analysis of VTCs in 16 segments using RT3DE may be a useful alternative to TDI for the evaluation of LV asynchrony.
Left bundle branch block as a risk factor for progression to heart failure
Authors: Zannad Faiez , Huvelle Etienne , Dickstein Kenneth , van Veldhuisen Dirk J. , Stellbrink Christoph , Køber Lars , Cazeau Serge , Ritter Philippe , Maggioni Aldo Pietro , Ferrari Roberto , Lechat Philippe 
Published: August 2006

AbstractThe prevalence of conduction disturbances, particularly left bundle branch block (LBBB), is strongly correlated with age and with the presence of cardiovascular disease. LBBB has been reported to affect approximately 25% of the heart failure (HF) population and it is likely that the deleterious role of such conduction disorders in the progression to HF has been underestimated.The purpose of this article is to review the data from the literature indicating that LBBB may have a causative role, mediated through the resulting intra‐ventricular asynchrony, in the deterioration of cardiac function and the development of cardiac remodelling and HF. It also aims to address the potential for future clinical therapies for this conduction disorder.
Pheochromocytoma induced cardiogenic shock with rapid recovery of ventricular function
Authors: Wu Grace Y. , Doshi Amit A. , Haas Garrie J. 
Published: August 2006

AbstractPheochromocytoma is a rare cause of secondary hypertension. It may present atypically as cardiogenic shock with significant morbidity and mortality. We present a patient in cardiogenic shock dependant on an intra‐aortic balloon pump and vasopressor support who completely recovered cardiac function within 96 h of hospitalization.
Heterotopic noxious conditioning stimulation (HNCS) reduced the intensity of spontaneous pain, but not of allodynia in painful peripheral neuropathy
Authors: Tuveson Birgitta , Leffler Ann‐Sofie , Hansson Per 
Published: August 2006

AbstractIn 15 patients with painful peripheral neuropathy and dynamic mechanical allodynia, the influence of spontaneous ongoing neuropathic pain on pain sensitivity in a remote pain‐free area was examined, as was the influence of ischemia‐induced heterotopic noxious conditioning stimulation (HNCS) on the intensity of ongoing pain and brush‐evoked allodynia. In addition, the modulating effect of HNCS on pain sensitivity in a pain‐free area was investigated. Pain thresholds to pressure and heat as well as the sensitivity to suprathreshold pressure‐ and heat pain were assessed in the pain‐free area. Dynamic mechanical allodynia was induced by a recently developed semi‐quantitative brushing technique and the patients continuously rated the intensity of the allodynia using a computerized visual analogue scale (VAS). The total brush‐evoked pain intensity was calculated as the area under the VAS curve. At baseline, no significant difference in pain sensitivity was found between patients and their healthy controls in the pain‐free area, indicating a lack of activation of pain modulatory systems from the spontaneous pain. Compared to baseline, the patients rated the ongoing neuropathic pain intensity significantly lower during the HNCS‐procedure (p<0.05). In contrast, there was no influence from HNCS on the total brush‐evoked pain intensity. In the pain‐free area higher pressure pain thresholds were demonstrated during conditioning stimulation in patients and controls alike (p<0.01). In controls only, a significantly higher heat pain threshold was found during the HNCS‐procedure (p<0.01). The main finding of the present study was that HNCS altered differentially spontaneous and brush‐provoked pain in patients with painful peripheral neuropathy.
A comparison of polysomnography and the SleepStrip in the diagnosis of OSA
Authors: Pang Kenny P. , Dillard Thomas A. , Blanchard Amy R. , Gourin Christine G. , Podolsky Robert , Terris David J. 
Published: August 2006

ObjectiveTo investigate the role of a portable screening device (SleepStrip) in the diagnosis of obstructive sleep apnea (OSA).Methods and MaterialsProspective, nonrandomized double‐blinded single cohort study at an academic health center. Patients with suspected OSA scheduled for an attended overnight Level I polysomnogram (PSG) and who consented to participate in the study wore the SleepStrip device at home the night after the PSG. The apnea‐hypopnea index (AHI) determined by PSG was compared with the results of the SleepStrip recording.ResultsThirty‐seven patients with a mean age of 52.1 ± 12.2 years and mean body mass index of 35.7 ± 5.2 participated in the study. The overall agreement between the AHI and the SleepStrip results using Cohen's Kappa value was 0.139 (P = 0.19). The sensitivity and specificity of the SleepStrip for diagnosing severe OSA when the AHI was >40 were 33.3% and 95% (P = 0.05). When the AHI was >25, the SleepStrip sensitivity and specificity were 43.8% and 81.3% (P = 0.26). The sensitivity and specificity of the SleepStrip for diagnosing OSA in patients with an AHI >15 were 54.6% and 70%, respectively (P = 0.26).ConclusionThe SleepStrip has a low correlation with the AHI as measured by PSG. Further studies are needed before this device can be recommended as a screening tool for the diagnosis of OSA.EBM rating: B‐2b
Management of recurrent sinus disease in children with cystic fibrosis: A combined approach
Authors: Anat Shatz 
Published: August 2006

ObjectiveTo determine whether a combined approach consisting of functional endoscopic sinus surgery (FESS), Caldwell‐Luc operation, and medial maxillectomy is beneficial for children with cystic fibrosis (CF) with refractory sinonasal disease previously treated with endoscopic procedures alone.Study DesignRetrospective review and comparison of outcomes of CA and FESS alone for each CF patient. Outcomes measured: sinonasal symptoms, endoscopic findings, number of hospitalizations, antibiotic courses, and forced expiratory volume in 1 second (FEV1).SettingReferral hospital.ResultsFifteen children underwent CA between 1996 and 2000 (7 males, 8 females; 13.8 years mean age; 42 months average follow‐up period). Significant decrease in number of hospitalizations and intravenous antibiotic courses, with increased mean FEV1 (from 70.2% preoperation to 89.3% postoperation, P <0.0001) were found. Marked clinical improvement persisted for several years.ConclusionApplying the CA after multiple failed endoscopic procedures in CF patients reduced morbidity and resulted in successful management of sinonasal disease. CA is suggested after multiple failed endoscopic procedures. Further studies of CA as a first‐line procedure for difficult sinus cases in children with CF is recommended.EBM rating: C‐4
Morphine/ondansetron PCA for postoperative pain, nausea, and vomiting after skull base surgery
Authors: Jellish W. Scott , Leonetti John P. , Kristina Sawicki , Douglas Anderson , Origitano Thomas C. 
Published: August 2006

ObjectivePatients who underwent skull base procedures have been noted to experience appreciable pain. This study examines pain after surgery and the effectiveness of patient controlled analgesia (PCA) with combination morphine ondansetron for analgesia and control of emesis.Study Design and SettingA total of 120 skull base surgery patients were randomized to receive placebo, morphine, or morphine ondansetron. Demographic and intraoperative variables were recorded along with pain, nausea, vomiting, and rescue analgesics. Total PCA use, hospital stay, satisfaction, and cost were also compared.ResultsDemographically the groups were similar. Pain was elevated with placebo PCA, and this group averaged twice as many analgesic rescues. Total usage time was lower with placebo PCA. Morphine ondansetron PCA had the lowest pain score with highest satisfaction. Nausea and vomiting was similar but female patients had more vomiting regardless of PCA group.Conclusions and SignificanceThe use of morphine PCA reduced pain and did not appreciably increase nausea or vomiting. The addition of ondansetron produced no real benefit and its PCA use cannot be justified.EBM rating: A‐1b© 2006 American Academy of Otolaryngology‐Head and Neck Surgery Foundation. All rights reserved.
Alloplastic bone cements in otologic surgery: Long‐term follow‐up and lessons learned
Authors: Saunders James E. 
Published: August 2006

ObjectiveOtolaryngologists are often confronted with structural defects in the tegmen, scutum, or external auditory canal. Carbonated calcium phosphate (CCP) bone cements offer an alternative way of managing these defects.Study Design and SettingRetrospective review in an academic otology practice. The technical feasibility of these techniques described as well as the wound healing and structural integrity results.ResultsCCP bone cement was used to reconstruct defects of the tegmen or EAC in 22 patients. The material was used to repair the EAC in 19 of these patients, including complete EAC reconstruction in 4 patients, and tegmen defects only in 3 cases.ConclusionThe surgical technique is not technically difficult and the alloplastic material is hard within minutes of application. Twenty patients have been followed for over 1 year with an average follow‐up period of 3.8 years. Failure, defined as infection or explantation, occurred in 4 patients followed over 3 years. There was a difference in outcomes for pediatric cases.EBM rating: C‐4
Treatment of pain after head and neck surgeries: Control of acute pain after head and neck oncological surgeries
Authors: Gil Ziv , Smith Darryl B. , Marouani Nissim , Khafif Avi , Fliss Dan M. 
Published: August 2006

ObjectiveTo devise an effective postoperative analgesic protocol.Study Design and SettingTwo consecutive groups participated in this study. In the first group (n = 100), the pain‐control management was pro re nata (PRN). In the second group, (n = 109) we tailored a procedure‐specific pain‐control protocol for each patient according to the level of pain recorded in the first group. These patients were treated with analgesics given at predetermined hours. Pain was evaluated by using a verbal scale of 1 to 10.ResultsIn the first group, a significant reduction in the level of pain was monitored 1 hour after PRN drug administration; however, patients reported the return of pain several hours later, after the drug effect subsided. Overall, the patients suffered a substantial level of pain during the entire postoperative period. In the second group, significant reduction in the level of pain was recorded throughout the hospitalization.ConclusionThe PRN protocol is not adequate for management of pain after head and neck surgeries.SignificanceWe can substantially reduce our patients' postoperative pain by adopting a procedure‐specific analgesic regimen instead of a PRN regimen.EBM rating: B‐3b.
Topical otic antibiotics: Clinical cochlear ototoxicity and cost consideration
Authors: Berenholz Leonard P. , Burkey John M. , Farmer Tonia L. , Lippy William H. 
Published: August 2006

ObjectiveDetermine the incidence of clinical cochlear ototoxicity in routine use of Cortisporin after ventilation tube placement. Cost differential between use of Cortisporin and fluoroquinolone agents was evaluated.MethodsA retrospective review of 500 patients was performed. Cortisporin otic suspension was used for 5 days following ventilation tube insertion.ResultsTesting following surgery indicated a sensorineural hearing loss in 19 (2.1%) ears. The SNHL existed prior to the surgery and there was no deterioration in the hearing postoperatively. The total cost for our study group who used Cortisporin was $15,500. If Floxin had been prescribed the cost would have been $45,000. Had Ciprodex been prescribed, the cost would have been $49,500.ConclusionOur study demonstrates no clinical cochlear ototoxicity in children who received Cortisporin following ventilation tube placement. The cost differential for prescribing flouroquinolone drops is significant.EBM rating: C‐4
Minimal incision for open thyroidectomy
Authors: Rafferty Mark , Miller Ian , Timon Conrad 
Published: August 2006

ObjectivesTo establish the incision length for thyroid surgery that optimizes access and cosmesis.Study Design and SettingProspective study from January 2003 to June 2004. All thyroidectomies were included. Exclusion criteria were concomitant neck dissections, previous surgery, and those performed endoscopically. The first 40 cases were attempted through a 5 cm incision and the second 40 through a 4 cm incision.MethodsIn both groups, the size of the incision was compared with the thyroid's weight and histology.ResultsTwo subtotal, 22 total, and 56 hemithyroidectomies were performed. In the first group, median gland weight was 39.5 gm and 62.5% of these were removed through a 5 cm incision. In the second group, median gland weight was 34 gm and 75% were removed through a 4 cm incision.ConclusionA 4 cm incision provides adequate access for the majority of thyroidectomies in our cohort.SignificanceThe minimal incision thyroidectomy is a useful addition to the thyroid surgeon's armamentarium.EBM rating: B‐3b
Long‐term results of cricopharyngeal myotomy in oculopharyngeal muscular dystrophy
Authors: Laurent Coiffier , Sophie Périé , Pascal Laforêt , Bruno Eymard , Jean Lacau St Guily 
Published: August 2006

ObjectiveTo analyze long‐term results of extramucosal cricopharyngeal myotomy in oculopharyngeal muscular dystrophy.Study DesignThe preoperative and postoperative evaluations including symptoms, type of feeding, weight, and functional examinations were retrospectively evaluated in 39 patients. Results were defined postoperatively as successful, partial, or failed.SettingUniversity hospital.ResultsIn the short term, 25 patients showed a complete remission of symptoms, 10 showed a marked improvement, and 4 exhibited no improvement at all (success rate of 90%). Long‐term evaluation during a mean follow‐up of 4 years showed that of the 35 improved patients, 12 exhibited a recurrence of dysphagia (mean time of 39 months). In 3 of these 12 patients, a revision transmucosal endoscopic cricopharyngeal myotomy was performed with a successful outcome in 2. Of the 4 patients who initially showed no improvement, 1 was improved by transmucosal myotomy.ConclusionExtramucosal cricopharyngeal myotomy improves dysphagia in oculopharyngeal muscular dystrophy patients during the first few years but one third of the patients exhibited a recurrence of symptoms within 3 years. Revision by transmucosal endoscopic myotomy may be performed.EBM rating: C‐4
Can a fluoroscopic estimation of pharyngeal constriction predict aspiration?
Authors: Yip Helena , Leonard Rebecca , Belafsky Peter C. 
Published: August 2006

BackgroundThe pharyngeal constriction ratio is a ratio of pharyngeal area measured in lateral fluoroscopic view at the point of maximum pharyngeal constriction during the swallow to the pharyngeal area measured with the bolus held in the oral cavity. We hypothesize that the PCR may represent a surrogate measure of pharyngeal strength.ObjectiveTo investigate the relationship between the PCR and aspiration.Study Design and SettingData from a computerized clinical database of individuals undergoing a videofluoroscopic swallow evaluation at a tertiary academic swallowing center was acquired.ResultsTwo hundred sixty videofluoroscopic studies were abstracted. The mean PCR was 0.32 (± 0.02) for individuals who aspirated and 0.20 (± 0.02) for individuals who did not (P < 0.001). In a multiple logistic regression analysis, the PCR was significantly associated with the prevalence of aspiration (P < 0.01). Individuals with a PCR greater than 0.25 were 3 times more likely to aspirate (95% CI = 1.7, 5.1).ConclusionsThe pharyngeal constriction ratio is associated with the presence of aspiration on fluoroscopy. Before the PCR can be used as a surrogate measure of pharyngeal constriction, correlation with pharyngeal manometry will be necessary.SignificanceThe pharyngeal constriction ratio is associated with the presence of aspiration on fluoroscopy.EBM rating: B‐3b
Primary head and neck Langerhans cell histiocytosis in children
Authors: Buchmann Luke , Emami Abbas , Wei Julie L. 
Published: August 2006

ObjectiveTo evaluate the experience of a tertiary care children's hospital in the diagnosis, treatment, and long‐term outcomes of patients with primary head and neck Langerhans' cell histiocytosis.Study Design and SettingA retrospective study of patients who presented with Langerhans' cell histiocytosis that primarily affected head and neck sites between January 1, 1986, and December 31, 2004, at Children's Mercy Hospital.ResultsTwenty‐two patients were diagnosed and treated for LCH at our hospital during this time period. Seventeen patients had head and neck involvement; 14 of these patients had primary head and neck LCH. Lesions of the head and neck are complicated and involve multiple structures including the calvarium and skull base. Overall outcomes were good with 10 of 14 patients without disease at time of last follow‐up. Recurrence is common and involved 50% of our patients.ConclusionsLangerhans' cell histiocytosis commonly affects the head and neck. These lesions are complex and require prudent evaluation and treatment. Due to the complex nature of head and neck lesions, primary chemotherapy is the treatment of choice.SignificanceBecause of the frequent head and neck involvement of this disease, otolaryngologists need to be familiar with its presentation, work‐up, and treatment.EBM rating: C‐4