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Abstract: A number of 1,3,1′,3′‐tetrasubstituted bisadamantylidenes are examined with 4 different density functional methods (BP86‐D3, ωB97X‐D, B3LYP, and B3LYP‐D3) and the 6‐311G(d) basis set. With increasing steric bulk, these substituted bisadamantylidenes become ever more twisted about the central carbon‐carbon double bond. This manifests in significantly reduced singlet‐triplet gaps from that of typical alkenes, with the tetra‐t‐butylbisadamantylidene 17, twisted to almost 90°, having a gap of only 2.2 kcal mol−1. While its large strain energy may preclude the synthesis of 17, other less‐strained tetrasubstituted analogues are more feasible synthetic targets and still possess small singlet‐triplet gaps, which should be testable by variable temperature NMR and EPR spectroscopy. The twisted alkenes also result in a low rotational energy barrier, and 4 examples with a low barrier to cis‐trans isomerization are presented. These too should be testable by experiment. [ABSTRACT FROM AUTHOR]

Despite tremendous progress over the past four decades, challenges remain in the field of computational organic chemistry. Challenges that are likely to be addressed in the near term include tackling the complexity of large configuration spaces, reactions where dynamic effects dictate product outcomes, design of enzymes to catalyze specific reactions, and the quest for a standard computational method. WIREs Comput Mol Sci 2014, 4:482-487. Conflict of interest: The author has declared no conflicts of interest for this article. For further resources related to this article, please visit the . [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to assess the rate of fracture before and after a 1-year course of intravenous pamidronate in children with spastic quadriplegic cerebral palsy (CP) who had previously experienced fractures. Method Twenty-five children (nine males, 16 females) with quadriplegic CP in Gross Motor Function Classification System (GMFCS) level IV or V who were treated with intravenous pamidronate for approximately 1 year were identified. All participants had previously experienced at least one non-traumatic fracture. Each received 15 doses of pamidronate over a mean of 13.6 months. Post-treatment observation ranged from 1 to 10 years 6 months (mean 4y 1mo). The fracture rate before and after commencement of treatment was calculated using the person-years method. Results The participants had experienced a total of 86 fractures before treatment began, occurring over 280.6 person-years, giving a fracture rate of 30.6% per year. During the post-treatment observation period, totalling 107.5 person-years, 8 of the 25 children experienced a total of 14 fractures. This fracture rate of 13.0% per year is a statistically significant decrease ( p=0.02). Interpretation Pamidronate treatment lowered the rate of fracture, and a 1-year course appears to provide a protective effect after treatment ends. For the majority of participants, this effect lasted 4 years or longer. However, a subset of children suffered a fracture soon after the drug was discontinued. In these children, a longer course of treatment appears to have been necessary. [ABSTRACT FROM AUTHOR]

Aim There is a lack of investigation into the functional developmental profile of children with Down syndrome. On the basis of current international health paradigms, the purpose of this study was to assess the developmental profile of these children. Method Sixty children (33 males, 27 females) with Down syndrome (age range 6–16y; mean age 9y 3mo, SD 28.8mo), who had received standard, holistic, early intervention, were assessed. Of these, 42 (70%) had congenital anomalies, 12 had severe congenital heart defects. Participants were assessed on measures of cognitive function (Beery–Buktenica Developmental Test of Visual–Motor Integration; Stanford–Binet Intelligence Scale) and participation (Vineland Adaptive Behaviour Scales). Results No difference was found on any measure on the basis of severity of congenital anomaly. Results showed improvements in age-related body function and correlations between specific body functions and participation. No decline in IQ was found with age, and significant correlations between IQ and all other measures were noted. Although sex differences were found in the body functions of short-term memory and motor function, no difference in measures of activity performance and participation was found. Interpretation Our findings emphasize the need for paediatric Down syndrome intervention to encourage improved body functions while emphasizing the acquisition of functional skills that enable enhanced participation in age-appropriate activities. [ABSTRACT FROM AUTHOR]

Mechanical loading plays an important role in skeletal health, and this is a major reason standing devices are widely used with non-ambulatory persons. However, little is known about the true axial loading that occurs while in a stander, or the factors which may impact loading. The purpose of this study was to quantify weight borne while in a stander, and to directly compare different standers. Load measuring footplate adaptors were designed and fabricated specifically for this study. Weight bearing loads in 20 non-ambulatory persons with quadriplegic cerebral palsy aged 6 to 21 years (median 14y) were continuously monitored during routine 30-minute standing sessions. Fourteen participants were female, six were male; one was Gross Motor Function Classification System (GMFCS) Level IV, and 19 were GMFCS Level V. Each participant was monitored on four to six occasions over an 8-week period, two to three times in each of two different standers (total 108 standing sessions). Weight bearing loads ranged widely from 37 to 101% of body weight. The difference between standers was as much as 29% body weight. There is wide variance in the actual weight borne while in passive standers. The type of stander utilized is one factor which can significantly affect the amount of weight borne. [ABSTRACT FROM AUTHOR]

Presents a study that attempted to resolve the question of whether pregnancy complications and perinatal trauma, including brain insults, in premature infants increase the susceptibility to eating disorder symptomatology during the adolescent years. Study population; Pregnancy and perinatal complications; Illnesses during the neonatal intensive care unit hospitalization.

Density functional theory and extrapolated CCSD(T) computations of several "anti‐Bredt" alkenes were carried to explore possible 1,2‐diyl "alkene" candidates with a triplet ground state. Ten candidates containing twisted double bonds at the bridgehead positions of bicyclic structures (1‐6) or adamantene (7‐10) derivatives were studied. Based on a combination of ring strain, rigid scaffolding, and steric crowding, four species were identified to have surprisingly low singlet‐triplet energy gaps (lower than 4 kcal/mol). A tert‐butyl substituted bicyclic structure (4) was identified to have a near‐zero singlet‐triplet energy gap, but no triplet ground‐state alkene was found. Ring strain energy (RSE) calculations, π‐orbital axis vector (POAV) analyses, and multiple linear regression models were performed to elucidate the geometric and energetic effects of double bond twisting in 1‐10. Based on our computational exploration, it appears unlikely that there is a ground‐state triplet olefin. [ABSTRACT FROM AUTHOR]

Review: 35 refs. [ABSTRACT FROM AUTHOR]

Review: 65 refs. [ABSTRACT FROM AUTHOR]

Aim To assess lower extremity bone mineral density (BMD) of children with congenital spinal dysfunction and examine factors that may influence BMD in this population. Method Forty-four children (25 females, 19 males) aged 6 to 18 years (mean 11y 11mo, SD 3y 6mo) with congenital spinal dysfunction (35 with myelomeningocele, seven with lipomas, one with sacral agenesis, one with caudal regression) were enrolled in the study. A health survey including ambulatory status, history of bladder augmentation, and history of fracture was administered. Each participant had a physical examination including Tanner stage and neurological level. Dual-energy X-ray absorptiometry scans of the lateral distal femur (LDF) and, when possible, lumbar spine were obtained. We reported LDF BMD results as z-scores for three regions of interest (metaphyseal, metadiaphyseal, and diaphyseal). Univariable and multivariable analyses examined relationships between LDF BMD and the other variables. Results BMD was significantly related to ambulatory status (14 non-ambulatory, 15 partly ambulatory, 15 fully ambulatory) and neurological level (13 with low-level lesions, 15 medium-level, 16 high-level) in the univariable analysis ( p<0.01 for both in all three regions). Neither history of fracture, nor Tanner stage, nor history of bladder augmentation showed a significant relationship to BMD. The significance of ambulatory status and neurological level in the univariable analysis failed to persist in the multivariable analysis of this study with a small sample size. Interpretation The LDF measurement proved to be a viable technique for assessing BMD in children with congenital spinal dysfunction. LDF BMD was sensitive to differences in three categories of ambulation. The overall influence of neurological level was not deemed as important as ambulation. [ABSTRACT FROM AUTHOR]