School Readiness Predictors of Early Academic Achievement in Children Born Very Preterm.

OBJECTIVE: This study examined associations of school readiness measures obtained before school entry with academic achievement at early school age in children born very preterm (VPT, gestational age ≤ 30 weeks) and children born full term (FT, GA ≥ 37 weeks). METHOD: The sample included 38 children born VPT and 30 born FT recruited at age 4 years and followed to early school age. Measures of readiness included tests of global cognition, executive function, motor abilities, and preacademic skills, as well as caregiver behavior ratings. Tests of math, reading, and spelling were administered to assess school-age achievement. Analyses that controlled for socioeconomic status and accounted for inclusion of siblings compared the groups on the achievement tests and identified measures of readiness related to school-age achievement. RESULTS: Achievement difficulties were more pronounced in the VPT group and associated with problems in multiple readiness domains. Effect sizes for these associations were largest for measures of spatial ability, executive function, and preacademic skills. Some associations remained significant when controlling for global cognitive ability at age 4 years, and others were significant only for the VPT group. CONCLUSION: Findings suggest that deficits on tests in multiple readiness domains assessed before school entry in children born VPT or FT are associated with early school-age achievement. The most pronounced readiness deficits in the VPT group at age 4 years were also among those most closely associated with later difficulties in achievement. Further research is needed to refine assessment of school readiness in children born VPT.

Long-Term Outcomes of Pediatric Traumatic Brain Injury Following Inpatient Rehabilitation.

OBJECTIVE: Assess residual disability in youth with traumatic brain injury (TBI) treated in a pediatric inpatient rehabilitation unit and examine associations of disability with inpatient status and measures of concurrent functioning. SETTING: Large, urban, quaternary care children's hospital in the Midwestern United States. PARTICIPANTS: Forty-five youth aged 6 to 18 years treated in an inpatient rehabilitation unit for mild-complicated to severe TBI at a minimum of 12 months postdischarge (mean = 3.5 years). DESIGN: Retrospective chart review of clinical data collected from standard clinical care at admission and discharge combined with follow-up data examining current functioning at the time of study enrollment. MAIN OUTCOME MEASURES: Glasgow Outcome Scale-Extended, Pediatric Revision (GOS-E Peds), Neurology Quality of Life Measurement System Short Form (NeuroQOL) Social Interaction with Peers and Cognitive Short Forms, Patient Reported Outcomes Measurement Information System (PROMIS) Global Health Scale, Strengths and Difficulties Questionnaire, and the Behavior Rating Inventory of Executive Function, 2nd Edition (BRIEF-2). RESULTS: Based on parent report at follow-up, 62% of the children had residual TBI-related disabilities on the GOS-E Peds, while 38% reported "good recovery." Children with residual disability also reported more long-term problems in overall health, social relationships, emotional regulation, behaviors, and executive functioning than those with no residual disability. Measures of functional independence and cognitive recovery at discharge were associated with these impairments. CONCLUSIONS: More than half of the children with TBI in this study had residual disability more than 1 year after inpatient rehabilitation. Findings highlight the associations between measures of functional independence and cognitive recovery during inpatient rehabilitation with later outcomes and underscore the need for continued services to support the needs of children with TBI following their inpatient rehabilitation stay.

Quality of Social Relationships with Parents and Peers in Adolescents Born Extremely Preterm.

OBJECTIVE: Adolescents born extremely preterm (EPT, gestational age [GA] <28 weeks) are at higher risk for problems in peer socialization than those born full-term (FT, GA >36 weeks). This study was designed to examine the possibility that adolescents born EPT may also have difficulty in transitioning from parents to peers for socialization, a process referred to as "social reorienting." A secondary aim was to investigate associations of social reorienting with other neurodevelopmental characteristics. METHODS: The Network of Relationships Inventory, Relationship Quality Version was administered to 24 adolescents (ages 11-16 years) born EPT and 29 born FT to obtain self-ratings of closeness and discord with parents and peers. Measures of other neurodevelopmental characteristics included tests of cognitive and social skills, adolescent self-ratings of adjustment and victimization, and parent ratings of youth behavior and adaptive skills. Mixed model analyses controlling for sex, socioeconomic status, and race were conducted to examine group differences in measures of relationship quality and their associations with other neurodevelopmental characteristics. RESULTS: The EPT group had higher ratings of closeness with parents than the FT group. For adolescents from lower socioeconomic backgrounds, those born EPT had lower closeness with peers. Higher closeness with parents was associated with lower test scores. Lower closeness and more discord with peers were associated with more behavior problems. CONCLUSION: Findings suggest that adolescents born EPT have difficulties in social reorientation toward peers and identify factors related to these difficulties. Results imply a need for interventions to improve peer socialization in youth born EPT.

Isokinetic profiling of elite youth footballers: informing selection of a practicable and efficacious isokinetic screening test.

Isokinetic dynamometry represents the clinical gold standard for strength assessment but testing lack consensus. Elite youth male football players (n = 28) completed 20 repetitions (analysed as four epochs) of eccentric knee flexor (eccKF) and concentric knee extensor (conKE) trials at 60, 180 and 270°âˆ™s-1, quantifying peak torque (PT) and functional range (FR). There was a significant (P < 0.001) main effect for fatigue and angular velocity in conKE PT; eccKF PT was not significant across epoch (P = 0.35) and velocity (P = 0.12) and a velocity x epoch interaction highlighted more repetitions were required to elicit fatigue as velocity increased. FR decreased with fatigue (P < 0.001) and velocity (P < 0.01) in conKE and eccKF, indicative of a narrowing of the strength curve. Clinical interpretation advocates an isokinetic test comprising at least 15 reps at a velocity ≥ 180°âˆ™s-1 and analysis beyond the peak of the strength curve (PT) to inform clinical reasoning and individualized exercise prescription.

Family matters: A systematic review and meta-analysis on the efficacy of family-oriented interventions for children with acquired brain injuries.

INTRODUCTION: Acquired brain injury (ABI) is a leading cause of disability among children. An increasing number of programs have emerged to involve family members as an integral component of post-ABI rehabilitation. This study aimed to conduct a systematic review and meta-analysis of such programs among children with ABI. METHODS: Following PRISMA guidelines, search among six databases (PsycINFO, PsycARTICLES, Scopus, Web of Science, PubMed, Cochrane CENTRAL) was conducted, followed by abstract/full-text screening and data extraction. Hedge's g was computed for effect sizes. The risk of bias was assessed using Cochrane guidelines. Meta-regression analyses were conducted on six moderators. RESULTS: A total of 32 studies (reported in 37 articles) were included in the qualitative analysis. Meta-analysis of 20 studies showed a positive small-to-medium effect of family-oriented interventions on child and parental outcomes but not on family functioning. Study design moderated the effect sizes of parent outcomes. CONCLUSIONS: This study synthesized the latest empirical evidence of family-oriented rehabilitation programs for pediatric ABI across interventional strategies, study designs, and outcomes. The findings suggested an overall beneficial impact of such programs on both the pediatric patients and their caregivers.

Establishing a reproducible approach to study cellular functions of plant cells with 3D bioprinting.

Capturing cell-to-cell signals in a three-dimensional (3D) environment is key to studying cellular functions. A major challenge in the current culturing methods is the lack of accurately capturing multicellular 3D environments. In this study, we established a framework for 3D bioprinting plant cells to study cell viability, cell division, and cell identity. We established long-term cell viability for bioprinted Arabidopsis and soybean cells. To analyze the generated large image datasets, we developed a high-throughput image analysis pipeline. Furthermore, we showed the cell cycle reentry of bioprinted cells for which the timing coincides with the induction of core cell cycle genes and regeneration-related genes, ultimately leading to microcallus formation. Last, the identity of bioprinted Arabidopsis root cells expressing endodermal markers was maintained for longer periods. The framework established here paves the way for a general use of 3D bioprinting for studying cellular reprogramming and cell cycle reentry toward tissue regeneration.

Electron Beam Melting of Niobium Alloys from Blended Powders.

Niobium-based tungsten alloys are desirable for high-temperature structural applications yet are restricted in practice by limited room-temperature ductility and fabricability. Powder bed fusion additive manufacturing is one technology that could be leveraged to process alloys with limited ductility, without the need for pre-alloying. A custom electron beam powder bed fusion machine was used to demonstrate the processability of blended Nb-1Zr, Nb-10W-1Zr-0.1C, and Nb-20W-1Zr-0.1C powders, with resulting solid optical densities of 99+%. Ultimately, post-processing heat treatments were required to increase tungsten diffusion in niobium, as well as to attain satisfactory mechanical properties.

Quasi-Static Tensile Properties of Unalloyed Copper Produced by Electron Beam Powder Bed Fusion Additive Manufacturing.

Mechanical properties of powder bed fusion processed unalloyed copper are reported majorly in the as-fabricated condition, and the effect of post-processes, common to additive manufacturing, is not well documented. In this study, mechanical properties of unalloyed copper processed by electron beam powder bed fusion are characterized via room temperature quasi-static uniaxial tensile test and Vickers microhardness. Tensile samples were extracted both perpendicular and parallel to the build direction and assigned to three different conditions: as-fabricated, hot isostatic pressing (HIP), and vacuum annealing. In the as-fabricated condition, the highest UTS and lowest elongation were obtained in the samples oriented perpendicular to the build direction. These were observed to have clear trends between sample orientation caused primarily by the interdependencies between the epitaxial columnar grain morphology and dislocation movement during the tensile test. Texture was insignificant in the as-fabricated condition, and its effect on the mechanical properties was outweighed by the orientation anisotropy. The fractographs revealed a ductile mode of failure with varying dimple sizes where more shallow and finely spaced dimples were observed in the samples oriented perpendicular to the build direction. EDS maps reveal that grain boundary oxides coalesce and grow in HIP and vacuum-annealed specimens which are seen inside the ductile dimples and contribute to their increased ductility. Overall, for the post-process parameters chosen in this study, HIP was observed to slightly increase the sample's density while vacuum annealing reduced the oxygen content in the specimens.

Tissue Regeneration with Hydrogel Encapsulation: A Review of Developments in Plants and Animals.

Hydrogel encapsulation has been widely utilized in the study of fundamental cellular mechanisms and has been shown to provide a better representation of the complex in vivo microenvironment in natural biological conditions of mammalian cells. In this review, we provide a background into the adoption of hydrogel encapsulation methods in the study of mammalian cells, highlight some key findings that may aid with the adoption of similar methods for the study of plant cells, including the potential challenges and considerations, and discuss key findings of studies that have utilized these methods in plant sciences.

Evaluation of Structural Anisotropy in a Porous Titanium Medium Mimicking Trabecular Bone Structure Using Mode-Converted Ultrasonic Scattering.

The mode-converted (longitudinal to transverse, L-T) ultrasonic scattering method was utilized to characterize the structural anisotropy of a phantom mimicking the structural properties of trabecular bone. The sample was fabricated using metal additive manufacturing from high-resolution computed tomography (CT) images of a sample of trabecular horse bone with strong anisotropy. Two focused transducers were used to perform the L-T ultrasonic measurements. A normal incidence transducer was used to transmit longitudinal ultrasonic waves into the sample, while the scattered transverse signals were received by an oblique incidence transducer. At multiple locations on the sample, four L-T measurements were performed by collecting ultrasonic scattering from four directions. The amplitude of the root mean square (rms) of the collected ultrasonic scattering signals was calculated for each L-T measurement. The ratios of rms amplitudes for L-T measurements in different directions were calculated to characterize the anisotropy of sample. The results show that the amplitude of L-T converted scattering is highly dependent on the direction of microstructural anisotropy. A strong anisotropy of the microstructure was observed, which coincides with simulation results previously published on the same structure as well as with the anisotropy estimated from the CT images. These results suggest the potential of mode-converted ultrasonic scattering methods to assess the anisotropy of materials with porous, complex structures, including trabecular bone.

Evaluation of 3D Additively Manufactured Canine Brain Models for Teaching Veterinary Neuroanatomy.

Physical specimens are essential to the teaching of veterinary anatomy. While fresh and fixed cadavers have long been the medium of choice, plastinated specimens have gained widespread acceptance as adjuncts to dissection materials. Even though the plastination process increases the durability of specimens, these are still derived from animal tissues and require periodic replacement if used by students on a regular basis. This study investigated the use of three-dimensional additively manufactured (3D AM) models (colloquially referred to as 3D-printed models) of the canine brain as a replacement for plastinated or formalin-fixed brains. The models investigated were built based on a micro-MRI of a single canine brain and have numerous practical advantages, such as durability, lower cost over time, and reduction of animal use. The effectiveness of the models was assessed by comparing performance among students who were instructed using either plastinated brains or 3D AM models. This study used propensity score matching to generate similar pairs of students. Pairings were based on gender and initial anatomy performance across two consecutive classes of first-year veterinary students. Students' performance on a practical neuroanatomy exam was compared, and no significant differences were found in scores based on the type of material (3D AM models or plastinated specimens) used for instruction. Students in both groups were equally able to identify neuroanatomical structures on cadaveric material, as well as respond to questions involving application of neuroanatomy knowledge. Therefore, we postulate that 3D AM canine brain models are an acceptable alternative to plastinated specimens in teaching veterinary neuroanatomy.

Multi-sample Arabidopsis Growth and Imaging Chamber (MAGIC) for long term imaging in the ZEISS Lightsheet Z.1.

Time-course imaging experiments on live organisms are critical for understanding the dynamics of growth and development. Light-sheet microscopy has advanced the field of long-term imaging of live specimens by significantly reducing photo-toxicity and allowing fast acquisition of three-dimensional data over time. However, current light-sheet technology does not allow the imaging of multiple plant specimens in parallel. To achieve higher throughput, we have developed a Multi-sample Arabidopsis Growth and Imaging Chamber (MAGIC) that provides near-physiological imaging conditions and allows high-throughput time-course imaging experiments in the ZEISS Lightsheet Z.1. Here, we illustrate MAGIC's imaging capabilities by following cell divisions, as an indicator of plant growth and development, over prolonged time periods. To automatically quantify the number of cell divisions in long-term experiments, we present a FIJI-based image processing pipeline. We demonstrate that plants imaged with our chamber undergo cell divisions for >16 times longer than those with the glass capillary system supplied by the ZEISS Z1.

Thermodynamic and fibril formation studies of full length immunoglobulin light chain AL-09 and its germline protein using scan rate dependent thermal unfolding.

Light chain (AL) amyloidosis is a fatal disease where monoclonal immunoglobulin light chains deposit as insoluble amyloid fibrils. For many years it has been considered that AL amyloid deposits are formed primarily by the variable domain, while its constant domain has been considered not to be amyloidogenic. However recent studies identify full length (FL) light chains as part of the amyloid deposits. In this report, we compare the stabilities and amyloidogenic properties of two light chains, an amyloid-associated protein AL-09 FL, and its germline protein κ I O18/O8 FL (IGKV 1-33). We demonstrate that the thermal unfolding for both proteins is irreversible and scan rate dependent, with similar stability parameters compared to their VL counterparts. In addition, the constant domain seems to modulate their amyloidogenic properties and affect the morphology of the amyloid fibrils. These results allow us to understand the role of the kappa constant domain in AL amyloidosis.

Overview of current additive manufacturing technologies and selected applications.

Three-dimensional printing or rapid prototyping are processes by which components are fabricated directly from computer models by selectively curing, depositing or consolidating materials in successive layers. These technologies have traditionally been limited to the fabrication of models suitable for product visualization but, over the past decade, have quickly developed into a new paradigm called additive manufacturing. We are now beginning to see additive manufacturing used for the fabrication of a range of functional end use components. In this review, we briefly discuss the evolution of additive manufacturing from its roots in accelerating product development to its proliferation into a variety of fields. Here, we focus on some of the key technologies that are advancing additive manufacturing and present some state of the art applications.

Development and validation of a canine radius replica for mechanical testing of orthopedic implants.

OBJECTIVE: To design and fabricate fiberglass-reinforced composite (FRC) replicas of a canine radius and compare their mechanical properties with those of radii from dog cadavers. SAMPLE: Replicas based on 3 FRC formulations with 33%, 50%, or 60% short-length discontinuous fiberglass by weight (7 replicas/group) and 5 radii from large (> 30-kg) dog cadavers. PROCEDURES: Bones and FRC replicas underwent nondestructive mechanical testing including 4-point bending, axial loading, and torsion and destructive testing to failure during 4-point bending. Axial, internal and external torsional, and bending stiffnesses were calculated. Axial pullout loads for bone screws placed in the replicas and cadaveric radii were also assessed. RESULTS: Axial, internal and external torsional, and 4-point bending stiffnesses of FRC replicas increased significantly with increasing fiberglass content. The 4-point bending stiffness of 33% and 50% FRC replicas and axial and internal torsional stiffnesses of 33% FRC replicas were equivalent to the cadaveric bone stiffnesses. Ultimate 4-point bending loads did not differ significantly between FRC replicas and bones. Ultimate screw pullout loads did not differ significantly between 33% or 50% FRC replicas and bones. Mechanical property variability (coefficient of variation) of cadaveric radii was approximately 2 to 19 times that of FRC replicas, depending on loading protocols. CONCLUSIONS AND CLINICAL RELEVANCE: Within the range of properties tested, FRC replicas had mechanical properties equivalent to and mechanical property variability less than those of radii from dog cadavers. Results indicated that FRC replicas may be a useful alternative to cadaveric bones for biomechanical testing of canine bone constructs.