bluuebunny/crossref_metadata_2025 huggingface dataset:
Not by bread alone project: a 2‐year follow‐up report
Authors: Taneja V. , Aggarwal R. , Beri R. S. , Puliyel J. M.
Published: October 2005

Background  We have previously reported the developmental gains achieved, after introducing a simple programme of structured play to stimulate children in an orphanage. It was envisaged that the caregivers could continue the programme. However, the enthusiasm of the caregivers waned over the year the programme was entrusted to them. After 1 year, a full time play therapist was recruited to rejuvenate the play programme.

Methods  Children's development was assessed using the Indian adaptation of the Bayley Scales of Infant Development. The first assessment was done when the play therapist joined. Subsequently, three‐monthly assessments were done and the scores achieved were recorded.

Results  The initial mean motor and mental scores, when the play therapist joined, were 66.14 and 56.95, respectively (similar to the pre‐intervention scores of the pilot study reported in an earlier paper). The scores improved to 81.84 and 78.25 within 3 months of restarting the play programme.

Conclusion  The schedule of the ‘Not by Bread Alone’ project can accelerate the motor and mental development of children in orphanages. However, it requires a highly motivated and dedicated person to sustain this programme over long periods.
Maternal responsiveness and infant intentional communication: implications for the early communicative and linguistic development
Authors: Paavola L. , Kunnari S. , Moilanen I.
Published: October 2005

Background  Maternal responsiveness has been found to have an important role in early language acquisition. From early on, children can also be regarded as active participants in interaction who demonstrate increasing competence in conveying messages to their interactive partners. Hence, in order to demonstrate consistent effects of maternal responses, it is important to take into account individual differences among children. In the present study, the relation between the frequencies of maternal responses and infant intentional communicative acts as well as their predictive validity to subsequent early communicative and linguistic skills was examined.

Methods  The participants were 27 Finnish‐speaking mothers and their healthy firstborn infants. Maternal and infant interactive behaviour was analysed from 20‐min samples of free play collected during home visits at the infants’ age of 10 months. At 12 months the children were assessed for their communicative and linguistic skills by using the Finnish version of the MacArthur Communicative Development Inventories and the Communication and Symbolic Behaviour Scales.

Results  The frequencies of maternal responses and infant intentional communicative acts were not intercorrelated. As for subsequent communicative and linguistic skills, the results of regression analyses indicated that both maternal responsiveness and infant intentional communication predict early comprehensive skills, whereas expressive skills – the use of both verbal and gestural communicative means – are predicted only by infant intentional communication.

Conclusion  The results of the present study suggest that maternal responsiveness during the prelinguistic stage is not necessarily dependent on children's communicative competence. As predictors of early communicative and linguistic skills, both maternal responsiveness and infant intentional communication make a distinctive contribution.
Relation between the changes in physical activity and body‐mass index during adolescence: a multicentre longitudinal study
Authors: Reading Richard
Published: October 2005

.
 
Kimm S.Y.S.,
Glynn N.W.,
Obarzanek E.,
Kriska A.M.,
Daniels S.R.,
Barton B.A.,
Liu K.
(
2005
)

,
366
,
301
–
307
.

Background  The role of physical activity in preventing obesity during adolescence remains unknown. We examined changes in activity in relation to changes in body‐mass index (BMI) and adiposity in a cohort of 1152 black and 1135 white girls from the USA, who were followed up prospectively from ages 9–19 years.

Methods  Body‐mass index and sum of skinfold thickness were assessed annually, whereas habitual activity was assessed at years 1 (baseline), 3, 5, and 7–10. Each girls’ overall activity status was categorized as active, moderately active, or inactive. Longitudinal regression models examined associations between changes in activity and in overall activity status with changes in BMI and in sum of skinfold thickness.

Findings  Each decline in activity of 10 metabolic equivalent [MET]‐times per week was associated with an increase in BMI of 0.14 kg/m2 (SE 0.03) and in sum of skinfold thickness of 0.62 mm (0.17) for black girls, and of 0.09 kg/m2 (0.02) and 0.63 mm (0.13) for white girls. At ages 18 or 19 years, BMI differences between active and inactive girls were 2.98 kg/m2 (P < 0.0001) for black girls and 2.10 kg/m2 (P < 0.0001) for white girls. Similar results were apparent for sum of skinfold thickness. For moderately active girls, changes in BMI and sum of skinfold thickness were about midway between those for active and inactive girls.

Interpretation  Changes in activity levels of US girls during adolescence significantly affected changes in BMI and adiposity. Thus, preventing the steep decline in activity during adolescence is an important method to reduce obesity.
Changing patterns of childhood mortality in Wolverhampton
Authors: Reading Richard
Published: October 2005

.
 
Moore A.
(
2005
)

,
90
,
687
–
691
.

Objectives  To review the incidence and characteristics of preventable childhood deaths in an urban population in the UK and to determine whether the excess of preventable deaths seen previously in Asian girls still exists.

Design  A retrospective survey of childhood deaths from 1996 to 2002 classified in terms of preventability and compared with a previous study conducted 20 years earlier from 1976 to 1982.

Setting  The city of Wolverhampton in the UK.

Main outcome measures  Deaths from all causes in children under the age of 5 years.

Results  There has been a reduction in the number of deaths in all age groups and from all causes. The post‐neonatal mortality rate fell from 6.5/1000 in 1976 to 3.1/1000 live births in 2002 largely because of the fall in the numbers of deaths caused by sudden infant death syndrome. Preventable deaths are still associated with low birth weight (P < 0.001) and poverty (unemployment and overcrowding in the earlier study (P < 0.05) and with the Townsend score in this study (P < 0.02). There were fewer deaths among Asians and no female excess. There was a new category not seen in the previous study, deaths caused by homicide. The death rate for homicide in the first year of life was much higher in Wolverhampton (18.7/100 000) than in England and Wales (4.6/100 000).

Conclusions  Low birth weight and adverse socio‐economic conditions remain important factors associated with preventable deaths. There is no longer an increased risk of preventable death in Asian girls. The number of non‐accidental deaths is a major cause for concern.
Moxidectin and ivermectin metabolic stability in sheep ruminal and abomasal contents
Authors: LIFSCHITZ A. , VIRKEL G. , BALLENT M. , SALLOVITZ J. , PIS A. , LANUSSE C.
Published: October 2005

The oral administration of macrocyclic lactones to sheep leads to poorer efficacy and shorter persistence of the antiparasitic activity compared to the subcutaneous treatment. Gastrointestinal biotransformation occurring after oral treatment to ruminant species has been considered as a possible cause of the differences observed between routes of administration. The current work was addressed to evaluate on a comparative basis the in vitro metabolism of moxidectin (MXD) and ivermectin (IVM) in sheep ruminal and abomasal contents. Both compounds were incubated under anaerobic conditions during 2, 6 and 24 h in ruminal and abomasal contents collected from untreated adult sheep. Drug concentrations were measured by high‐performance liquid chromatography with fluorescence detection after sample clean up and solid phase extraction. Neither MXD nor IVM suffered metabolic conversion and/or chemical degradation after 24‐h incubation in ruminal and abomasal contents collected from adult sheep. Unchanged MXD and IVM parent compounds represented between 95.5 and 100% of the total drug recovered in the ruminal and abomasal incubation mixtures compared with those measured in inactive control incubations. The partition of both molecules between the solid and fluid phases of both sheep digestive contents was assessed. MXD and IVM were extensively bound (>90%) to the solid material of both ruminal and abomasal contents collected from sheep fed on lucerne hay. The results reported here confirm the extensive degree of association to the solid digestive material and demonstrates a high chemical stability without evident metabolism and/or degradation for both MXD and IVM in ruminal and abomasal contents.
PK‐PD modeling of buprenorphine in cats: intravenous and oral transmucosal administration1
Authors: ROBERTSON S. A. , LASCELLES B. D. X. , TAYLOR P. M. , SEAR J. W.
Published: October 2005

The pharmacokinetics and thermal antinociceptive effects of buprenorphine after intravenous (i.v.) or oral transmucosal (OTM) administration were studied in six adult cats. Plasma buprenorphine concentrations were measured using radioimmunoassay in a crossover study after a dose of 20 μg/kg given by the i.v. or OTM route. Oral pH was measured. Blood for drug analyses was collected before, and at 1, 2, 4, 6, 10, 15, 30, and 60 min and at 2, 4, 6, 8, 12, and 24 h after treatment. Thermal thresholds were measured before treatment, then following treatment every 30 min to 6 h, every 1 hour to 12 h and at 24 hours postadministration. Plasma buprenorphine concentration effect relationships were analyzed using a log‐linear effect model. Oral pH was 9 in each cat. Peak plasma buprenorphine concentration was lower and occurred later in the OTM group but median bioavailability was 116.3%. Thermal thresholds increased significantly between 30 and 360 min in both groups. Peak effect was at 90 min and there was no difference at any time between the two groups. There was distinct hysteresis between plasma drug concentration and effect in both groups. Overall, OTM administration of buprenorphine is as effective as i.v. treatment and offers a simple, noninvasive method of administration which produces thermal antinociception for up to 6 h in cats.
The effects of inhibiting cytochrome P450 3A, p‐glycoprotein, and gastric acid secretion on the oral bioavailability of methadone in dogs
Authors: KUKANICH B. , LASCELLES B. D. X. , AMAN A. M. , MEALEY K. L. , PAPICH M. G.
Published: October 2005

Methadone is an opioid, which has a high oral bioavailability (>70%) and a long elimination half‐life (>20 h) in human beings. The purpose of this study was to evaluate the effects of ketoconazole [a CYP3A and p‐glycoprotein (p‐gp) inhibitor] and omeprazole (an H+,K+‐ATPase proton‐pump inhibitor) on oral methadone bioavailability in dogs. Six healthy dogs were used in a crossover design. Methadone was administered i.v. (1 mg/kg), orally (2 mg/kg), again orally following oral ketoconazole (10 mg/kg q12 h for two doses), and following omeprazole (1 mg/kg p.o. q12 h for five doses). Plasma concentrations of methadone were analyzed by high‐pressure liquid chromatography or fluorescence polarization immunoassay. The mean ± SD for the elimination half‐life, volume of distribution, and clearance were 1.75 ± 0.25 h, 3.46 ± 1.09 L/kg, and 25.14 ± 9.79 mL/min·kg, respectively following i.v. administration. Methadone was not detected in any sample following oral administration alone or following oral administration with omeprazole. Following administration with ketoconazole, detectable concentrations of methadone were present in one dog with a 29% bioavailability. MDR‐1 genotyping, encoding p‐gp, was normal in all dogs. In contrast to its pharmacokinetics humans, methadone has a short elimination half‐life, rapid clearance, and low oral bioavailability in dogs and the extent of absorption is not affected by inhibition of CYP3A, p‐gp, and gastric acid secretion.
Enrofloxacin pharmacokinetics in the European cuttlefish, Sepia officinalis, after a single i.v. injection and bath administration
Authors: GORE S. R. , HARMS C. A. , KUKANICH B. , FORSYTHE J. , LEWBART G. A. , PAPICH M. G.
Published: October 2005

Enrofloxacin pharmacokinetics were studied in European cuttlefish, Sepia officinalis, after a single 5 mg/kg i.v. injection or a 2.5 mg/L 5 h bath. A pilot study with two animals was also performed following a 10 mg/kg p.o. administration. The concentration of enrofloxacin in hemolymph was assayed using high‐performance liquid chromatography (HPLC) and pharmacokinetic parameters were derived from compartmental methods. In the i.v. study, the terminal half‐life (t1/2), apparent volume of distribution, and systemic clearance were respectively 1.81 h, 385 mL/kg, and 4.71 mL/min/kg. Following bath administration the t1/2, peak hemolymph concentration (Cmax), and area under the curve to infinity (AUC0−∞) were 1.01 h, 0.5 ± 0.12 μg/mL, and 0.98 μg·h/mL, respectively. After oral administration, the t1/2, Cmax, and AUC0−∞ were 1.01 h, 10.95 μg/mL, 26.71 μg·h/mL, respectively. The active metabolite of enrofloxacin, ciprofloxacin, was not detected in any samples tested. The hemolymph concentration was still above minimum inhibitory concentration (MIC) values for shrimp and fish bacterial isolates at 6 h after i.v. administration, therefore, a dose of 5 mg/kg i.v. every 8–12 h is suggested for additional studies of efficacy. The Cmax value for the water bath was lower than for the i.v. study, but a bath of 2.5 mg/L for 5 h once to twice daily is suggested for additional studies to test efficacy against highly susceptible organisms. Although only two animals were used for the oral study, a dose of 10 mg/kg produced hemolymph concentrations of enrofloxacin that were in a range consistent with therapeutic efficacy in other species.
Surgical Approaches to Recipient Vessels of the Fore‐ and HindLimbs for Microvascular Free Tissue Transfer in Dogs
Authors: Degner Daniel A. , Walshaw Richard , David Fowler J. , Lanz Otto I. , Ocello Peter , Maier Jackie , Blaezer Loren , Smith Rick J.
Published: October 2005

Objective—To develop and evaluate surgical approaches to the arteries and veins of the fore‐ and hindlimbs for use as potential recipient vessels for free tissue transfer.

Study Design—Experimental anatomic study.

Sample Population—Canine cadavers (11): 2 preserved and 9 fresh cadavers.

Methods—Fore‐ and hindlimbs from 1 preserved cadaver injected with a pigmented silicone/barium mixture, through the common carotid artery and external jugular vein, were cut in 1 cm cross‐sections. Tissue sections were used to identify the location of vessels >1 mm that could be used as recipient vessels for free tissue transfer. The other preserved cadaver was used to develop surgical approaches to these vessels. Three surgeons evaluated the written descriptions and illustrations for these approaches using fresh cadavers. Modifications to the surgical approaches were made based on recommendations from these surgeons.

Results—Six approaches were developed to isolate forelimb recipient vessels: palmar access, distal medial antebrachial, mid‐antebrachial, proximal antebrachial, distal humeral, and mid‐humeral vascular access. Twelve approaches were developed to isolate recipient vessels of the hindlimb: plantar access, dorsal tarsal, cranial distal tibial, craniomedial distal tibial, lateral distal tibial, medial distal tibial, medial femorotibial, lateral distal femoral, medial femoral, proximal medial femoral, groin, and proximal lateral femoral vascular access.

Conclusions—Six forelimb and 12 hindlimb sites were identified for surgical access to recipient vessels (>1 mm diameter) suitable for use in free tissue transfer for wound reconstruction.

Clinical Relevance—For reconstruction of complex wounds of the extremities of dogs, surgeons should consider use of readily accessible recipient vessels that would allow for free tissue transfer to the fore‐ and hindlimbs.
Synovial Membrane Microarthroscopy of the Equine Midcarpal Joint
Authors: Serena Alberto , Hanson R. Reid , Kincaid Steven A.
Published: October 2005

Objective— To evaluate the value of microarthroscopy in the equine midcarpal joint using the vital stains methylene blue, trypan blue, neutral red, and Janus green B to observe components of the synovial lamina propria, vascular architecture, and synoviocytes.

Study design— Experimental.

Animals— Ten horses.

Methods— Microarthroscopy of left and right midcarpal joints was performed with and without vital staining of the synovium. Four vital stains (methylene blue, trypan blue, neutral red, and Janus green B) were evaluated, with each stain used in 5 joints. Synovial biopsy specimens were collected from the dorsomedial and dorsolateral aspects of the joint.

Results— All dyes were biocompatible. At × 60 without vital staining, synovial surface topography, vascular network, and translucency were observed. Intra‐articular vital dyes improved evaluation of synovial surface topography. At × 150 with vital staining, individual synoviocytes were clearly identified with all dyes, except neutral red. Although methylene blue provided the best in vivo microscopic differentiation of the structure of the intima, trypan blue had superior retention in conventionally processed synovial biopsies.

Conclusions— Methylene blue, trypan blue, neutral red, and Janus green B stains can be used safely for microarthroscopy. Good visualization of cells and vascular network can be obtained by microarthroscopy, and microarthroscopic evaluation of the synovium compares favorably with conventional histologic evaluation of biopsy specimens.

Clinical relevance— Microarthroscopy may be beneficial in both research and clinical diagnosis of equine articular diseases.
Short‐Term Aseptic Loosening of the Femoral Component in Canine Total Hip Replacement: Effects of Cementing Technique on Cement Mantle Grade
Authors: Ota Juri , Cook James L. , Lewis Daniel D. , Tomlinson James L. , Fox Derek B. , Cook Cristi R. , Schultz Loren G. , Brumitt Jason
Published: October 2005

Objectives— To evaluate the effects of different cementing techniques on radiographic cement mantle grade and short‐term aseptic loosening of the femoral component in canine total hip replacement (THR).

Study Design— Retrospective study.

Sample Population— Radiographs of 284 dogs that had THR.

Methods— Immediate postoperative radiographs of 284 dogs that had cemented THR were reviewed by 4 surgeons and 1 radiologist and assigned a cement mantle grade using a 4‐grade classification system. Dog age and weight at surgery, cementing technique (1st, 2nd, 3rd generation), complications (type and timing), and follow‐up time were retrieved and analyzed.

Results— Mean cement mantle score for 2nd generation technique was significantly higher than 3rd generation technique and both were significantly higher than 1st generation technique (P<.001). Aseptic loosening was the 2nd most common complication observed with an incidence of 2.1%. Mean time from surgery to last follow‐up examination was 122 days. No statistically significant difference in incidence of aseptic loosening was identified among different cement mantle grades or cementing techniques.

Conclusions— Advanced cementing techniques resulted in better cement mantles based on grading of immediate postoperative radiographs, however grading did not predict short‐term aseptic loosening. Cementing technique seemingly did not affect the incidence of short‐term aseptic loosening of the femoral component for dogs in this study.

Clinical Relevance— Our study suggests that advances in cementing technique may result in improvements in the radiographic grade of cement mantles. With respect to aseptic loosening of the femoral component, our data only suggest that short‐term (3 months–3 years) loosening cannot be predicted by immediate postoperative radiographic evaluation of cement mantle.
Neodymium:Yttrium Aluminum Garnet Surgical Laser Versus Bipolar Electrocoagulation for Laparoscopic Ovariectomy in Dogs
Authors: Van Nimwegen Sebastiaan A. , Van Swol Christiaan F. P. , Kirpensteijn Jolle
Published: October 2005

Objective—To compare use of neodymium:yttrium aluminum garnet (Nd:YAG) surgical laser and bipolar electrocoagulation (BEC) for laparoscopic ovariectomy (OVE) in dogs.

Study Design—Prospective clinical trial.

Animals—Female dogs (n=72).

Methods—Laparoscopic OVE by Nd:YAG laser (600 μm optical fiber, contact mode) in 36 dogs was compared with laparoscopic OVE by bipolar electro‐coagulating grasping forceps. Dogs were paired (laser, electrocoagulation) matched for breed, age, body weight, obesity, and number of heat cycles. Duration of predetermined surgery times and total surgical time were compared between groups. Occurrence of intra‐ and postoperative complications and their effect on surgical duration were evaluated.

Results—Laser surgery resulted in a higher incidence of intraoperative mesovarial bleeding (12 times; 9 dogs) compared with electrosurgery (4 times; 3 dogs). Use of laser caused a 2 minute delay for transection of the left ovary compared with electrosurgery. Postoperative complication rates and convalescence were similar for both groups.

Conclusions—BEC reduced surgical time and intraoperative mesovarial bleeding compared with laser resection.

Clinical Relevance—Although the laser was effective for laparoscopic OVE, bipolar electrosurgical laparoscopic OVE remained the method of choice.
Teat Tip Reconstruction by Supernumerary Teat Autotransplantation in Cattle
Authors: Saifzadeh Siamak , Ardebili Farhad Farrokhi , Hobbenaghi Rahim , Farid Jafar
Published: October 2005

Objective—Evaluation of use of a supernumerary teat as a pedicle graft to repair experimental teat tip damage in cattle.

Study Design—Experimental study.

Animals—Mature, non‐gravid hybrid cows with ≥1 supernumerary teat.

Methods—The main teat and adjacent supernumerary teat were examined for patency by ultrasound with a 8 MHz linear array transducer. The tip of the main teat was resected at the junction of cistern and canal. The supernumerary teat was partially resected semi‐circumferentially at the cranial aspect of the base to maintain vascular supply and transplanted by end‐to‐end anastomosis. The pedicle of the supernumerary teat graft was amputated in stages starting at 14 days, again at 16 days and separated at 18 days. Reconstructed teat patency was evaluated at intervals by ultrasonography and confirmed at 50 days by histopathology. Repeated measures ANOVA was used to compare the measurements of luminal diameter between days; significance was set atP<.05.

Results—All reconstructed teats were patent. Decreased luminal diameters were detected at 25, 32, 39, and 46 days by ultrasonography. On histopathology, granulation and epithelial (mucosal) proliferation contributed to luminal reduction.

Conclusions—In this experimental model of an acute damage to a teat tip, supernumerary teat grafting was successfully used to restore teat anatomy.

Clinical Relevance—Supernumerary teat pedicle grafting may be considered as a salvage technique for reconstruction of a damaged bovine teat in cows that have an adjacent patent supernumerary teat. Function of the reconstructed teat in a lactating cow remains unknown.
Laser Fenestration of the Mesial Septum for Treatment of Guttural Pouch Chondroids in a Pony
Authors: Gehlen Heidrun , Ohnesorge Bernhard
Published: October 2005

Objective—To describe removal of guttural pouch chondroids through a laser fenestrated mesial septum in a pony with an obstructed pharyngeal ostium of the left guttural pouch.

Study Design—Case report.

Animals—Pony.

Methods—Transendoscopic laser neodymium:yttrium aluminum garnet (Nd:YAG) fenestration of the mesial guttural pouch septum was made by contact method (bare fiber, 15–25 W, exposure time 4 seconds). Dissected tissue was removed by transendoscopic monopolar electrosurgery (loop electrode, cutting blade) and multiple chondroids of varying size were removed from the left guttural pouch through the fenestration.

Results—After removing all chondroids and repeated flushing of the left guttural pouch via the right side, inflammation of the guttural pouch membranes decreased remarkably. The pony was discharged with instructions for transendoscopic lavage once weekly and was reevaluated at 2 months. A permanent septal fenestration was observed and the pony was free of abnormal clinical signs and being used for carriage driving competitions.

Conclusion—Nd:YAG laser fenestration of the mesial septum is an approach for access to guttural pouch chondroids.

Clinical Relevance—When guttural pouch empyema and/or chondroids is associated with adhesion of the pharyngeal ostium, laser fenestration of the mesial septum from the opposite guttural pouch should be considered as an alternative approach for access, rather than classic external surgical approaches.
Protective role of melatonin in pinealectomized rat brains: in vivo magnetic resonance spectroscopic analysis
Authors: Hascalik Seyma , Celik Onder , Karakas Hakki Muammer , Parlakpinar Hakan , Firat Ahmet K. , Ozsahin Murat
Published: October 2005

Abstract:  The goal of this study was to investigate the effect of melatonin on basic cerebral metabolites in pinealectomized (Px) rat brains. Twenty‐one rats were randomly divided into three groups with seven rats per group. The study groups included sham‐operated rats, Px rats and Px rats treated with melatonin. Melatonin administration began at 60 days following pinealectomy and continued for 21 days. At the end of the study, in vivo single voxel magnetic resonance spectroscopy was performed on whole brains to determine choline (Cho), creatine and N‐acetyl aspartate (NAA) concentrations. Px rats had significantly lower NAA levels (P < 0.05), and significantly higher Cho levels (P < 0.05) when compared with sham‐operated rats. Administration of melatonin had normalized NAA and Cho levels in Px rats. We propose that pinealectomy causes significant changes in cerebral metabolites which are compatible with neural loss. Melatonin administration prevents the disruptive effects of pinealectomy on brain tissue.
Melatonin provokes cell death in human B‐lymphoma cells by mitochondrial‐dependent apoptotic pathway activation
Authors: Trubiani Oriana , Recchioni Rina , Moroni Fausto , Pizzicannella Jacopo , Caputi Sergio , Di Primio Roberto
Published: October 2005

Abstract:  Apoptosis is an important cell suicide programme involved in physiological and pathological processes. Apoptosis can be induced in different ways depending on cell type and acquired signal. Melatonin, the major secretory product of the pineal gland, participates in many important physiological functions and displays a remarkable functional versatility exhibiting antioxidant, oncostatic, anti‐aging, and immunomodulatory properties. Recently, it has been shown that, in addition to pineal gland, human lymphoid cells are an important physiological source of melatonin and that may be involved in the regulation of the immune system. In this work, we examine the effect of melatonin on RAMOS‐1 human leukaemic cells. Cell growth and viability, DNA fragmentation and JC‐1, and annexin V expression have been determined. To elucidate the mechanism of action of melatonin, Western blot analyses for Bcl‐2 and caspase‐3 expression, and cytochrome c release were carried out. The results suggest that the apoptotic effect of melatonin is associated with cell‐cycle arrest, downregulation of Bcl‐2, mitochondrial membrane depolarization, cytochrome c release and activation of caspase‐3. The intrinsic (mitochondrial dependent) pathway of caspase activation is the ‘point of no return’ commitment to cell death. Taken together, our study indicates that melatonin may play a role as potential therapeutic drug in specific lymphoproliferative diseases.
Industrial Sensor TBCs: Studies on Temperature Detection and Durability
Authors: Chen X. , Mutasim Z. , Price J. , Feist J. P. , Heyes A. L. , Seefeldt S.
Published: October 2005

This article describes recent developments of the thermal barrier sensor concept for non‐destructive evaluation (NDE) of thermal barrier coatings (TBCs) and on‐line condition monitoring in gas turbines. Increases in turbine entry temperature in pursuit of higher efficiency will make it necessary improve or upgrade current thermal protection systems in gas turbines. As these become critical to safe operation it will also be necessary to devise techniques for on‐line conditions monitoring and NDE. Thermal barrier sensor coatings, which consist of a ceramic doped with rare‐earth activator to provide luminescence, may be a possible solution. The thermo‐luminescent response of such materials has been shown to be suitable for surface and sub‐surface temperature measurement and possibly for material phase determination. Herein we describe a number of steps in the development of the sensor coating technology. For the first time sensor coatings have been successfully produced using a production standard air plasma spray (APS) process. Microscopic analysis of the coatings showed them to be similar to standard TBCs and thermal cycle testing of the coatings to destruction showed them to exhibit durability similar to that of standard TBCs suggesting that the addition of rare earth dopants to produce sensor coatings does not change the material structure or the longevity of coatings. Calibration of the coatings using the lifeteime decay response mode showed them to have a dynamic range for temperature measurement extending to just under 1000°C. However, it should be noted that newer compositions have been shown to respond up to 1300°C. Finally, a study of surface temperatures and film cooling has been conducted in a research combustor using APS sensor coatings and some preliminary results are presented.
An ASTM Standard for Quantitative Scratch Adhesion Testing of Thin, Hard Ceramic Coatings
Authors: Gonczy Stephen T. , Randall Nicholas
Published: October 2005

Thin, hard ceramic coatings on metals and ceramics are extensively used for wear and abrasion resistance, friction control, corrosion resistance, and tailored functional (electrical, optical, and magnetic) properties across a wide range of high‐performance applications. Coating producers and users have to measure and control the coating‐substrate adhesion strength, because adhesion failure is often the primary failure mechanism of the coating, limiting its performance and life. The quantitative test method of choice for thin hard coatings is scratch adhesion testing. In this technique, a diamond stylus is drawn across the coating on the surface under increasing normal load and the damage to the coating is assessed against the applied load. With DOE funding and in coordination with the ASTM Committees C28, G08, and B02, a new scratch adhesion test standard has been researched and written and has been published. The ASTM C1624 test standard (Adhesion Strength and Mechanical Failure Modes of Ceramic Coatings by Quantitative Scratch Testing) provides comprehensive and detailed guidance and instructions on scratch adhesion testing of thin, hard ceramic coatings—the principles, terminology, applications, limitations, equipment, specimen preparation and characterization, critical experimental factors, calibration, procedures, calculations, and reporting requirements.
Cardiac cone‐beam CT
Authors: Manzke Robert
Published: October 2005

This doctoral thesis addresses imaging of the heart with retrospectively gated helical cone‐beam computed tomography (CT). A thorough review of the CT reconstruction literature is presented in combination with a historic overview of cardiac CT imaging and a brief introduction to other cardiac imaging modalities. The thesis includes a comprehensive chapter about the theory of CT reconstruction, familiarizing the reader with the problem of cone‐beam reconstruction. The anatomic and dynamic properties of the heart are outlined and techniques to derive the gating information are reviewed. With the extended cardiac reconstruction (ECR) framework, a new approach is presented for the heart‐rate‐adaptive gated helical cardiac cone‐beam CT reconstruction. Reconstruction assessment criteria such as the temporal resolution, the homogeneity in terms of the cardiac phase, and the smoothness at cycle‐to‐cycle transitions are developed. Several reconstruction optimization approaches are described: An approach for the heart‐rate‐adaptive optimization of the temporal resolution is presented. Streak artifacts at cycle‐to‐cycle transitions can be minimized by using an improved cardiac weighting scheme. The optimal quiescent cardiac phase for the reconstruction can be determined automatically with the motion map technique. Results for all optimization procedures applied to ECR are presented and discussed based on patient and phantom data. The ECR algorithm is analyzed for larger detector arrays of future cone‐beam systems throughout an extensive simulation study based on a four‐dimensional cardiac CT phantom. The results of the scientific work are summarized and an outlook proposing future directions is given. The presented thesis is available for public download at www.cardiac‐ct.net.
Monte Carlo portal dosimetry
Authors: Chin Pik Wai
Published: October 2005

This project developed a solution for verifying external photon beam radiotherapy. The solution is based on a calibration chain for deriving portal dose maps from acquired portal images, and a calculation framework for predicting portal dose maps. Quantitative comparison between acquired and predicted portal dose maps accomplishes both geometric (patient positioning with respect to the beam) and dosimetric (two‐dimensional fluence distribution of the beam) verifications. A disagreement would indicate that beam delivery had not been according to plan. The solution addresses the clinical need for verifying radiotherapy both pretreatment (without the patient in the beam) and on treatment (with the patient in the beam). Medical linear accelerators mounted with electronic portal imaging devices (EPIDs) were used to acquire portal images. Two types of EPIDs were investigated: the amorphous silicon and the scanning liquid ion chamber (SLIC). The EGSnrc family of Monte Carlo codes were used to predict portal dose maps by computer simulation of radiation transport in the beam‐phantom‐EPID configuration. Monte Carlo simulations have been implemented on several levels of high throughput computing (HTC), including the grid, to reduce computation time. The solution has been tested across the entire clinical range of gantry angle, beam size , and beam‐patient and patient‐EPID separations . In these tests of known beam‐phantom‐EPID configurations, agreement between acquired and predicted portal dose profiles was consistently within 2% of the central axis value. This Monte Carlo portal dosimetry solution therefore achieved combined versatility, accuracy, and speed not readily achievable by other techniques.
Dose‐response characteristics of an amorphous silicon EPID
Authors: Winkler Peter , Hefner Alfred , Georg Dietmar
Published: October 2005

Electronic portal imaging devices (EPIDs) were originally developed for the purpose of patient setup verification. Nowadays, they are increasingly used as dosimeters (e.g., for IMRT verification and linac‐specific QA). A prerequisite for any clinical dosimetric application is a detailed understanding of the detector's dose‐response behavior. The aim of this study is to investigate the dosimetric properties of an amorphous silicon EPID (Elekta IVIEWGT) with respect to three photon beam qualities: 6, 10, and . The EPID showed an excellent temporal stability on short term as well as on long term scales. The stability throughout the day was strongly influenced by warming up, which took several hours and affected EPID response by 2.5%. Ghosting effects increased the sensitivity of the EPID. They became more pronounced with decreasing time intervals between two exposures as well as with increasing dose. Due to ghosting, changes in pixel sensitivity amounted up to 16% (locally) for the photon beam. It was observed that the response characteristics of our EPID depended on dose as well as on dose rate. Doubling the dose rate increased the EPID sensitivity by 1.5%. This behavior was successfully attributed to a dose per frame effect, i.e., a nonlinear relationship between the EPID signal and the dose which was delivered to the panel between two successive readouts. The sensitivity was found to vary up to 10% in the range of 1 to 1000 monitor units. This variation was governed by two independent effects. For low doses, the EPID signal was reduced due to the linac's changing dose rate during startup. Furthermore, the detector reading was influenced by intrabeam variations of EPID sensitivity, namely, an increase of detector response during uniform exposure. For the beam qualities which were used, the response characteristics of the EPID did not depend on energy. Differences in relative dose‐response curves resulted from energy dependent temporal output characteristics of the accelerator. If ghosting is prevented from affecting the results and all dose‐response effects are properly corrected for, the EPID signal becomes independent of dose rate, dose, and exposure time.
Optimal steel thickness combined with computed radiography for portal imaging of nasopharyngeal cancer patients
Authors: Wu Shixiu , Jin Xiance , Xie Congying , Cao Guoquan
Published: October 2005

The poor image quality of conventional metal screen‐film portal imaging system has long been of concern, and various methods have been investigated in an attempt to enhance the quality of portal images. Computed radiography (CR) used in combination with a steel plate displays image enhancement. The optimal thickness of the steel plate had been studied by measuring the modulation transfer function (MTF) characteristics. Portal images of nasopharyngeal carcinoma patients were taken by both a conventional metal screen‐film system and this optimal steel and CR plate combination system. Compared with a conventional metal screen‐film system, the CR‐metal screen system achieves a much higher image contrast. The measured modulation transfer function (MTF) of the CR combination is greater than conventional film‐screen portal imaging systems and also results in superior image performance, as demonstrated by receiver operator characteristic (ROC) analysis. This optimal combination steel CR plate portal imaging system is capable of producing high contrast portal images conveniently.
Stability of a mobile electron linear accelerator system for intraoperative radiation therapy
Authors: Beddar A. Sam
Published: October 2005

The flexibility of mobile electron accelerators, which are designed to be transported to an operating room and plugged into a normal 3‐phase outlet, make them ideal for use in intraoperative radiation therapy. However, their transportability may cause trepidation among potential users, who may question the stability of such an accelerator over a period of use. In order to address this issue, we have studied the short‐term stability of the Mobetron system over 20 daily quality assurance trials. Variations in output generally varied within for the four energies produced by the unit (4, 6, 9, and ) and changes in energy produced an equivalent shift of less than on the depth‐dose curve. Hours of inactivity, with the Mobetron powered on for use either throughout the day or overnight, led to variations in output of about 1%. Finally, we have tested the long‐term stability of the absolute dose output of the Mobetron, which showed a change of about 1% per year.
Helical cone beam CT with an asymmetrical detector
Authors: Zamyatin Alexander A. , Taguchi Katsuyuki , Silver Michael D.
Published: October 2005

If a multislice or other area detector is shifted to one side to cover a larger field of view, then the data are truncated on one side. We propose a method to restore the missing data in helical cone‐beam acquisitions that uses measured data on the longer side of the asymmetric detector array. The method is based on the idea of complementary rays, which is well known in fan beam geometry; in this paper we extend this concept to the cone‐beam case. Different cases of complementary data coverage and dependence on the helical pitch are considered. The proposed method is used in our prototype 16‐row CT scanner with an asymmetric detector and a field of view. For evaluation we used scanned body phantom data and computer‐simulated data. To simulate asymmetric truncation, the full, symmetric datasets were truncated by dropping either 22.5% or 45% from one side of the detector. Reconstructed images from the prototype scanner with the asymmetrical detector show excellent image quality in the extended field of view. The proposed method allows flexible helical pitch selection and can be used with overscan, short‐scan, and super‐short‐scan reconstructions.
Composition of MRI phantom equivalent to human tissues
Authors: Kato Hirokazu , Kuroda Masahiro , Yoshimura Koichi , Yoshida Atsushi , Hanamoto Katsumi , Kawasaki Shoji , Shibuya Koichi , Kanazawa Susumu
Published: October 2005

We previously developed two new MRI phantoms (called the CAG phantom and the CAGN phantom), with T1 and T2 relaxation times equivalent to those of any human tissue at . The conductivity of the CAGN phantom is equivalent to that of most types of human tissue in the frequency range of . In this paper, the relaxation times of human tissues are summarized, and the composition of the corresponding phantoms are provided in table form. The ingredients of these phantoms are carrageenan as the gelling agent, as a T1 modifier, agarose as a T2 modifier, NaCl (CAGN phantom only) as a conductivity modifier, as an antiseptic, and distilled water. The phantoms have T1 values of and T2 values of when the concentrations of and agarose are varied from , and 0%–1.6%, respectively, and the CAGN phantom has a conductivity of when the NaCl concentration is varied from 0%–0.7%. These phantoms have sufficient strength to replicate a torso without the use of reinforcing agents, and can be cut by a knife into any shape. We anticipate the CAGN phantom to be highly useful and practical for MRI and hyperthermia‐related research.
Concert hall acoustic criteria; subjective significance
Authors: Sotiropoulou Alexandra G.
Published: October 2005

The validity of current physical room acoustic criteria developed by various authors in the laboratory has been tested for the first time under the environmental complexity of live concerts. Six independent subjective factors emerged from evaluations on semantic rating scales, namely body, clarity, tonal quality, proximity, spaciousness, and intimacy. In a correlation analysis between subjective factors and measured values of physical room acoustic parameters, the factors clarity and intimacy were not found to be related with any of the physical parameters. The factor body correlated with the ratio of 80-ms Late-to-Early energy, tonal quality with the texture of the impulse response decay, and proximity with the direct-to-reverberant energy ratio and distance from platform. Each of the factors body, tonal quality, and proximity were also found to be the effect of an additional objective influence which remained unidentified [A. G. Sotiropoulou, Ph.D. thesis, University of London (1982)]. These results show that there is redundancy in current physical room acoustic criteria, and that the list of physical criteria which account for good acoustics is still incomplete. [Thanks go to Dr. David B. Fleming for invaluable advice.]
A new task-oriented conversational mode speech recognition system
Authors: Levinson S. E. , Rabiner L. R. , Terrace S. G. , Shipley K. L.
Published: October 2005

A conversational mode-connected speech recognition system which simulates the function of an airline ticket agent is described. The system which allows a complete spoken dialog over dialed-up telephone lines comprises a syntax-directed dynamic programming temporal alignment algorithm [C. S. Meyers and S. E. Levinson, IEEE Trans. Acoust. Speech Signal Process. ASSP-30, 561–565 (1982)] for acoustic pattern recognition and a semantic processor [S. E. Levinson and K. L. Shipley, Bell Syst. Tech. J. 59, 119–137 (1980)] that controls an audio response system making two-way speech communication possible. The system is highly robust and operates on-line in ten times real time in speaker trained mode (or 60 times in speaker-independent mode) on a 32-bit minicomputer/array processor combination. The heterarchical nature of the system allows it some intelligent processing such as the ability to recognize incorrect, incomplete, improbable, and/or conflicting information in the context of the transaction and to pose questions which identify the difficulty thereby allowing communication to proceed in a natural way.
Effects of noise on distinctive feature information in normal and whispered speech
Authors: Voiers William D. , Panzer Ira L.
Published: October 2005

It is common knowledge that the bulk of the intelligibility-relevant information in English speech is carried by the consonants, which are generally of lower intensity and shorter duration than the vowels. This led us to hypothesize that, except for its effect on voicing information, whispered speech would permit more efficient use of communication channel space than would normal speech. The Diagnostic Rhyme Test (DRT) was used to test this hypothesis with noise-masked speech. Under extreme S/N conditions, normal speech yielded higher DRT total scores than did whispered speech, but, over the range from −6 to +9 dB S/N ratio, whispered speech yielded significantly higher scores. When the contribution of the voicing scale to total DRT scores was removed, whispered speech yielded uniformly higher scores. The DRT score for voicing was predictability the most affected by whispering. However, significantly greater than chance amounts of voicing information survived all but the least favorable conditions. Noise caused a substantial loss of information with respect to several features in normal speech, while having negligible effects in the case of whispered speech.
Consonant errors in noise and reverberation
Authors: Nabelek Anna K. , Robinson Pauline K.
Published: October 2005

Consonant errors in noise and reverberation were compared. In CVC syllables the variables were 24 initial or 21 final consonants that exist in English words while the constant consonant was /t/ and the vowels were /ɑ/ and /i/. All syllables were produced by a male talker in a carrier sentence: “Mark the /CVC/ again.” The tests were processed through a room with reverberation time, T = 1.2 s or a babble of 20 voices was added. The following conditions were tested: (1) no noise and no reverberation; (2) no noise, T = 1.2 s; and (3) no reverberation, noise at speech-to-noise ratio, S/N = + 5 dB. Each condition was tested 20 times by 10 normal hearing subjects. The responses were tabulated in 12 matrices: 2 vowels×2 positions of consonants×3 test conditions. Transmitted information, TI, was calculated for selected distinctive features for each matrix separately. Analysis of variance was performed for each distinctive feature. Many main effects and two-way interactions were significant. Diffferences in errors in noise and reverberation will be discussed. [Supported by NIH.]