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Herein two new and concise synthetic approaches for making an unsaturated bicyclic oxamazin core are reported. The first involves the use of an intramolecular Diels–Alder reaction to form both of the fused rings in one step. The second approach incorporates ring-closing olefin metathesis in the final step to form the second fused ring of the core. The scope of the second approach was also expanded further to afford larger ringed bicyclic systems. [ABSTRACT FROM AUTHOR]

The article discusses a study comparing the effects of a supported speed treadmill training exercise program (SSTTEP) with exercise on spasticity, strength, gait spatiotemporal parameters, motor control, physical function, and gross motor skills in children with spastic cerebral palsy (CP). Results showed improvements in gait, speed, cadence and Pediatric Outcomes Data Collection Instrument (PODCI) scores. The gains in PODCI global scores and gait speed were also maintained by those in the SSTTEP group after the intervention's withdrawal.

Aim The aim of this study was to determine the psychometric properties, content range, and measurement precision of a lower extremity physical functioning and mobility skills item bank (LE85) in children with cerebral palsy (CP). Method Lower extremity functioning and mobility skill items were administered to 308 parents of children (169 males, 139 females; mean age 10y 8mo, SD 4y) with spastic CP (145 diplegia, 73 hemiplegia, 89 quadriplegia; [for one person type of CP was unknown]) classified using the Gross Motor Function Classification System (75 level I, 91 level II, 79 level III, 37 level IV, 26 level V). Additional legacy measures were administered to assess concurrent validity. Psychometric characteristics, differential item functioning, content range, and score precision were examined. Results The LE85 had acceptable psychometric properties. Content range matched the ability range of the sample population and exceeded legacy measures with minimal differential item functioning. The LE85 had good correlation with the Paediatric Outcomes Data Collection Instrument, Functional Independence Measure for Children, Gillette Functional Assessment Questionnaire, and Paediatric Quality of Life Inventory – CP module (range r=0.63–0.86). Precision of the LE85 and 10-item simulated computer adaptive test scores outperformed legacy measures. Interpretation The LE85 appears to be suitable to administer as a computer adaptive test to measure lower extremity physical functioning and mobility in children with CP. [ABSTRACT FROM AUTHOR]

Abstract: The use of fluorine as an oxidizing agent in aluminum (Al)-based thermite reactions yields higher peak pressures and an increase in gas production compared with oxygen-containing oxidizers, such as molybdenum trioxide (MoO3). Thus fluorination reactions have the potential to excel in situations that require high pressures and flame speeds. This study compares the combustion behaviors of Al/Teflon, Al/MoO3/Teflon, and Al/MoO3 in an effort to determine the effects that the replacement of oxygen with fluorine has on the reaction dynamics in both open and confined burning configurations. Data were collected from pressure sensors and high-speed imaging. The mass percent of Al was varied from 10 to 90% to study the effects of composition. The composites were then further tested at the optimum stoichiometry using either 50 nm or 1–3 μm Al to examine the effect of Al particle size. The addition of Teflon in an open configuration hinders the reaction due to a loss of liberated gas. Confining the reaction enables the trapped gases to enhance convection, yielding increased flame speeds. For confined conditions, the reactions containing Teflon exhibit higher peak pressures but lower flame speeds than the reactions with MoO3. These results imply that a direct relationship between generated gas pressures and flame speeds does not generally exist when comparing different oxidizers. The theoretically predicted relationship for the relative flame speed versus relative particle size based on the melt-dispersion mechanism agrees with experimental data for all Al particle sizes and for the fluorination reaction. Particle synthesis parameters are suggested that could be controlled to enable micrometer-scale Al particles to achieve the performance of nanoscale Al particles. This is of significant practical importance, because nanoparticles are 30 to 50 times more expensive than the micrometer particles. [Copyright &y& Elsevier]

The successful approach to bicyclic oxamazins (III) relies on a Mitsunobu reaction to form β-lactams (II) selectively, followed by a ring closing metathesis (RCM). [ABSTRACT FROM AUTHOR]

The objective of this project was to develop computer-adaptive tests (CATs) using parent reports of physical function in children and adolescents with cerebral palsy (CP). The specific aims of this study were to (1) examine the psychometric properties of an item bank of lower-extremity and mobility skills for children with CP; (2) evaluate a CAT using this item bank; (3) examine the concurrent validity of the CAT with the Pediatric Outcomes Data Collection Instrument (PODCI) and the Functional Assessment Questionnaire (FAQ); and (4) establish the discriminant validity of simulated CATs with Gross Motor Function Classification System (GMFCS) levels and CP type (diplegia, hemiplegia, or quadriplegia). Parents ( n=190) of children and adolescents with spastic diplegic (48%), hemiplegic (22%), or quadriplegic (30%) CP consisting of 108 males and 82 females with a mean age of 10 years 7 months (SD 4y 1mo, range 2–21y) and in GMFCS levels I to V participated in item pool calibration and completed the PODCI and FAQ. Confirmatory factor analyses supported a unidimensional model for the 45 basic lower-extremity and mobility items. Simulated CATs of 5, 10, and 15 items demonstrated excellent accuracy (intraclass correlation coefficients [ICCs] >0.91) with the full item bank and had high correlations with PODCI transfers and mobility (ICC = 0.86) and FAQ scores (ICC = 0.77). All CATs discriminated among GMFCS levels and CP type. The lower-extremity and mobility skills item bank and simulated CATs demonstrated excellent performance over a wide span of ages and severity levels. [ABSTRACT FROM AUTHOR]

The theoretically predicted relationship for the relative flame rate versus relative particle size based on the melt dispersion mechanism (MDM), which was previously confirmed for oxidation of 40–120 nm diameter aluminum particles, is found to be in agreement with experiments for 1–3 μm diameter Al particles and fluorination. The main physical parameters for MDM (pressure in molten particle, cavitation threshold, and nanoclusters’ velocity) have been estimated for micron scale particles. The results suggest parameters that could be controlled during particle synthesis that would enable micron scale Al particles to react and achieve the performance of nanoscale Al particles. [ABSTRACT FROM AUTHOR]

Abstract: Selective catalytic reduction (SCR) was used to reduce exhaust gas nitrogen oxides (NO x ) from the emissions of a 710kW combined heat and power system fueled by dairy biogas. Exhaust gas NO x was reduced from 63.1±31.9 to 14.2±17.5ppmvd@15% O2 such that emissions were 0.33±0.40gkW−1 h−1, based on data averaged over 15min intervals. Online exhaust gas sensors with integrated process control algorithms were effective in improving NO x removal by automated control of urea, the ammonia source used for catalysis of NO x reduction reactions. Pre-SCR NO x was most strongly correlated with equivalence ratio (R 2 =0.39), indicative of the air–fuel ratio. A concave relationship between NO x production and thermal conversion efficiency was not observed since lean-burn operation of the engine was consistent and only altered under low engine load. Following installation of pre- and post-SCR NO x sensors, average daily exhaust gas NO x reduction in the SCR was 82.6±8.5%. Post-SCR NO x emissions were typically impacted by pre-SCR NO x (R 2 =0.36), suggesting that altered operation of the anaerobic digesters or modifications to the engine would be effective in reducing NO x emissions as well as urea demand. After nearly three years of operation, the SCR catalyst remains in service without requiring replacement. Average daily urea demand was 31.8±16.3Ld−1 for the system that produced 369±136kW of electricity. During the second year of observation the regulatory limit of 0.804gkW−1 h−1 was met 94% of the time while the regulatory target of 0.201gkW−1 h−1 was only met 45% of the time, based on data averaged over 15min intervals. These results provide guidance for dairy energy projects in locations with stringent NO x emissions standards. [Copyright &y& Elsevier]

The specific aims of this study were to (1) examine the psychometric properties (unidimensionality, differential item functioning, scale coverage) of an item bank of upper-extremity skills for children and adolescents with cerebral palsy (CP); (2) evaluate a simulated computer-adaptive test (CAT) using this item bank; (3) examine the concurrent validity of the CAT with the Pediatric Outcomes Data Collection Instrument (PODCI) upper-extremity core scale; and (4) determine the discriminant validity of the simulated CAT with Manual Ability Classification System (MACS) levels and CP type (i.e. diplegia, hemiplegia, or quadriplegia). Parents ( n=180) of children and adolescents with CP (spastic diplegia 49%, hemiplegia 22%, or quadriplegia 28%) consisting of 102 males and 78 females with a mean age of 10 years 6 months (SD 4y 1mo, range 2–21y), and MACS levels I through V participated in calibration of an item pool and completed the PODCI. Confirmatory factor analyses supported a unidimensional model using 49 of the 53 upper-extremity items. Simulated CATs of 5, 10, and 15 items demonstrated excellent accuracy (intraclass correlation coefficient [ICCs] >0.93) with the full item bank, had high correlations with the PODCI upper-extremity core scale score (ICC 0.79), and discriminated among MACS levels. The simulated CATs demonstrated excellent overall content coverage over a wide age span and severity of upper-extremity involvement. The future development and refinement of CATs for parent report of physical function in children and adolescents with CP is supported by our work. [ABSTRACT FROM AUTHOR]

Background. Contemporary clinical assessments of activity arc needed across the age span for children with cerebral palsy (CP). Computerized adaptive testing (CAT) bat the potential to efficiently administer items for children across wide age spans and functional levels. Objective. The objective of this study was to examine the psychometric properties of a new item bank and simulated computerized adaptive test to assess activity level abilities in children with CP. Design. This was a cross-sectional item calibration study. Methods. The convenience sample consisted of 308 children and youth with CP, aged 2 to 20 years (X=10.7, SD=4.O), recruited from 4 pediatric hospitals We collected parent-report data on an initial set of 45 activity items. Using an Item Response Theory (IRT) approach, we compared estimated scores from the activity item bank with concurrent instruments, examined discriminate validity, and developed computer simulations of a CAT algorithm with multiple stop rules to evaluate scale coverage, score agreement with CAT algorithms, and discriminant and concurrent validity. Results. Confirmatory factor analysis supported scale unidimensionally, local item dependence, and invariance. Scores from the computer simulations of the prototype CATs with varying stop rules were consistent with scores from the full item bank (r=.93-.98). The activity summary scores discriminated across levels of Upper-extremity and gross motor severity and were correlated with the Pediatric Outcomes Data Collection Instrument (PODCl) physical function and sports subscale (r=.H6). the Functional Independence Measure for Children (Wee-FIM) (r=.79), and the Pediatric Quality of Life Inventory-Cerebral palsy version (r=.74). Limitations. The sample size was small for such IRT item banks and CAT development studies. Another limitation was oversampling of children with CP at higher functioning levels. Conclusions. The new activity item bank appears to have promise for use in a CAT application for the assessment of activity abilities in children with CP across a wide age range and different levels of motor severity. [ABSTRACT FROM AUTHOR]

The purposes of this study were to apply a bi-factor model for the determination of test dimensionality and a multidimensional CAT using computer simulations of real data for the assessment of a new global physical health measure for children with cerebral palsy (CP). Parent respondents of 306 children with cerebral palsy were recruited from four pediatric rehabilitation hospitals and outpatient clinics. We compared confirmatory factor analysis results across four models: (1) one-factor unidimensional; (2) two-factor multidimensional (MIRT); (3) bi-factor MIRT with fixed slopes; and (4) bi-factor MIRT with varied slopes. We tested whether the general and content (fatigue and pain) person score estimates could discriminate across severity and types of CP, and whether score estimates from a simulated CAT were similar to estimates based on the total item bank, and whether they correlated as expected with external measures. Confirmatory factor analysis suggested separate pain and fatigue sub-factors; all 37 items were retained in the analyses. From the bi-factor MIRT model with fixed slopes, the full item bank scores discriminated across levels of severity and types of CP, and compared favorably to external instruments. CAT scores based on 10- and 15-item versions accurately captured the global physical health scores. The bi-factor MIRT CAT application, especially the 10- and 15-item versions, yielded accurate global physical health scores that discriminated across known severity groups and types of CP, and correlated as expected with concurrent measures. The CATs have potential for collecting complex data on the physical health of children with CP in an efficient manner. [ABSTRACT FROM AUTHOR]