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PubMed1997

Sheltered homeless children: their eligibility and unmet need for special education evaluations.

OBJECTIVES: This study described the proportion of sheltered homeless children in Los Angeles, Calif, who were eligible for special education evaluations because of a probable behavioral disorder, learning disability, or mental retardation, and to explore their level of unmet need for special education services. METHODS: This was a cross-sectional study of 118 parents and 169 children aged 6 through 12 years living in 18 emergency homeless family shelters in Los Angeles County, California. Parents and children were interviewed with standardized mental health and academic skill measures in English and Spanish. RESULTS: Almost half (45%) of the children met criteria for a special education evaluation, yet less than one quarter (22%) had ever received special education testing or placement. The main point of contact for children with behavioral disorders and learning problems was the general health care sector. CONCLUSIONS: School-aged sheltered homeless children have a high level of unmet need for special education evaluations, the first step toward accessing special education programs. Interventions for homeless children should include integration of services across special education, general health care, and housing service sectors.

California↗
PubMed1979

["General special education" - defining a questionable area of theory, action and research (author's transl)].

Special education is characterized as an integral part of education in general, and of the interdisciplinary field of rehabilitation. Its close relationship to social work/social education and its dependence on relevant related disciplines are pointed out. The establishment of a "general special educational theory" is regarded as problematic and theoretically impossible, as concrete and differentiated educational statements must always be made in relation to quite definite groups of pupils and/or educational needs. Theoretical reflections and practical actions in the field of special education are, therefore, necessarily directed towards persons with certain types of disabilities and/or specific special educational needs. While "General Special Education" (or "Education of the Handicapped") is rejected as an intermediate field of theory between general education and specific special educational theories, the importance of interdisciplinary and comparative actions in the area of special education and some other overlapping tasks in this field are emphasized.

Education, Special↗
PubMed1996

Financing special education.

The best available data indicate that approximately 12% of K-12 public education budgets are allocated to special education and that the cost per student is about 2.3 times the cost of regular education. About 8% of special education funds come from the federal government, 56% from state governments, and the remainder from local school districts. However, the division of fiscal responsibility between state and local sources varies considerably from state to state. Fiscal pressures on special education have increased markedly in recent years as a result of increasing overall school populations, increasing proportions of students found eligible for special education services, and increasing fiscal pressures on schools. At least six states have recently adopted, and the federal Department of Education has recently recommended, special education funding based on census counts of total school populations rather than on the number of students identified for special education services. Proponents of census-based funding foresee greater efficiency of services, while opponents fear a loss of services targeted to individualized needs. An additional proposal is that census-based funding be modified to increase funding to jurisdictions with higher rates of poverty. Criteria for evaluating state special education funding formulas are proposed.

Costs and Cost Analysis↗
PubMed1993

Ectoplasmic ("junctional") specializations in Sertoli cells of the rooster and turtle: evolutionary implications.

Ectoplasmic specializations are complex actin-containing structures found at certain sites of intercellular attachment in Sertoli cells. Current evidence indicates that these structures are a form of actin-associated adhesion junction. In the turtle (Pseudemys scripta) and rooster (Gallus domesticus) ectoplasmic specializations are known to occur adjacent to sites of attachment to elongate spermatids and are characterized by a layer of "loosely" cross-linked actin filaments that lies next to the plasma membrane. In the turtle, a cistern of endoplasmic reticulum is associated with the cytoplasmic face of the filament layer. We have found that, in fixed frozen sections of turtle and rooster testes, immunological probes for myosin II react with epithelial regions that also stain with probes for filamentous actin and that are known to be sites at which ectoplasmic specializations occur. Furthermore, when exposed to standard contraction buffers, the diameters of glycerinated ectoplasmic specializations of the turtle are statistically smaller than those of the same structures exposed to control buffers. We interpret these smaller diameters as being produced by the contraction of actin bundles within the ectoplasmic specializations. Our results indicate that ectoplasmic specializations in the rooster and turtle, unlike those in mammals, possess contractile properties. We speculate that ectoplasmic specializations in eutherian mammals may have evolved from actin-associated adhesion junctions in which the actin bundles were initially contractile and from which myosin II was secondarily lost.

Actins↗
PubMed2006

Asymmetric specialization and extinction risk in plant-flower visitor webs: a matter of morphology or abundance?

A recently discovered feature of plant-flower visitor webs is the asymmetric specialization of the interaction partners: specialized plants interact mainly with generalized flower visitors and specialized flower visitors mainly with generalized plants. Little is known about the factors leading to this asymmetry and their consequences for the extinction risk of species. Previous studies have proposed random interactions proportional to species abundance as an explanation. However, the simulation models used in these studies did not include potential biological constraints. In the present study, we tested the potential role of both morphological constraints and species abundance in promoting asymmetric specialization. We compared actual field data of a Mediterranean plant-flower visitor web with predictions of Monte Carlo simulations including different combinations of the potential factors structuring the web. Our simulations showed that both nectar-holder depth and abundance were able to produce asymmetry; but that the expected degree of asymmetry was stronger if based on both. Both factors can predict the number of interaction partners, but only nectar-holder depth was able to predict the degree of asymmetry of a certain species. What is more, without the size threshold the influence of abundance would disappear over time. Thus, asymmetric specialization seems to be the result of a size threshold and, only among the allowed interactions above this size threshold, a result of random interactions proportional to abundance. The simulations also showed that asymmetric specialization could not be the reason that the extinction risk of specialists and generalists is equalized, as suggested in the literature. In asymmetric webs specialists clearly had higher short-term extinction risks. In fact, primarily generalist visitors seem to profit from asymmetric specialization. In our web, specialists were less abundant than generalists. Therefore, including abundance in the simulation models increased the difference between specialists and generalists even more.

Adaptation, Biological↗
PubMed1995

The cochlea of Tadarida brasiliensis: specialized functional organization in a generalized bat.

Tadarida brasiliensis mexicana employs a broad-band sonar system at frequencies between 80 and 20 kHz and is characterized by non-specialized hearing capabilities. The cochlear frequency map was determined with extracellular horseradish peroxidase tracing in relation to quantitative morphological data obtained with light, scanning and transmission electron microscopy. These data reveal distinct species characteristic specializations clearly separate from the patterns observed in other bats with either broad-band or narrow-band sonar systems. The basilar membrane (BM) is coiled to 2.5 turns and about 12 mm long. Its thickness and width only change within the extreme basal and apical ends. The frequency range from about 30 to 80 kHz is represented in the lower basal turn with a typically mammalian mapping coefficient of about 3 mm/octave. This region exhibits morphological features correlated with non-specialized processing of high frequencies. (1) The BM is radially segmented by thickenings of pars tecta and pars pectinata. (2) The 3 rows of outer hair cells (OHCs) have similar morphology. Between 35 and 86% distance from base, frequencies between 30 and 12 kHz are represented with a slightly expanded mapping coefficient of about 6 mm/octave. In analogy to previous work, this cochlea region is termed acoustic fovea. It includes the frequency range of maximum sensitivity and sharpest tuning (21-27 kHz) but also frequencies below the sonar signals. The fovea is characterized by several morphological specializations. (1) The BM features a continuous radial thickening mainly composed of hyaline substance. (2) There is an increased number of layers of tension fibroblasts in the spiral ligament. (3) There are morphological differences in the arrangements of stereocilia bundles among the 3 rows of OHCs. The transitions between non-specialized and specialized cochlear regions occur gradually within a distance of about 600 microns. The gradients in stereocilia length of both receptor cell types and the gradations in length of the OHC bodies match specialized aspects of the frequency map.

Acoustic Stimulation↗
PubMed2005

Testing the trend towards specialization in herbivore-host plant associations using a molecular phylogeny of Tomoplagia (Diptera: Tephritidae).

Herbivorous insects are abundant and diverse and insect-host plant associations tend to be specialized and evolutionarily conserved. Some authors suggested that generalist insect lineages tend to become specialists, with host specialization leading to an evolutionary dead-end for the parasite species. In this paper, we have examined this tendency using a phylogenetic tree of Tomoplagia (Diptera: Tephritidae), a parasite of asteracean plants. We have tested the trend towards specialization in different hierarchical degrees of host specialization. The topology of the tree, the inference of ancestral hosts, and the lack of directional evolution indicated that specialization does not correspond to a phylogenetic dead-end. Although most Tomoplagia species are restricted to a single host genus, specialization does not seem to limit further host range evolution. This work emphasizes the advantages of the use of different levels of specialization and the inclusion of occasional hosts to establish a more detailed scenario for the evolution of this kind of ecological association.

Adaptation, Biological↗
PubMed2003

Consumer-provider communication research with special populations.

As the US population becomes increasingly diverse, understanding consumer-provider communication among special populations becomes of paramount importance. Cultural competence is a key element in improving communication between non-minority providers and minority patients. This includes overcoming sociocultural and linguistic barriers that hinder access to care and diminish quality consumer-provider communication. Of special concern is the lack of cancer prevention communication between providers and their special population patients. More research is needed to understand cancer communication needs and barriers among special populations, and to direct effective interventions to improve consumer-provider communication for special populations. To this end, interactive training to improve communication skills among oncologists and medical students, increasing the availability of trained medical translators, increasing the number of health professionals from special populations, and increasing the number of special population participants in communication research are recommended. Furthermore, research should focus on identifying and overcoming cultural factors that negatively impact consumer-provider interactions.

Clinical Competence↗
PubMed1996

Mg coordination by amino acid side chains is not required for assembly and function of the special pair in bacterial photosynthetic reaction centers.

A conserved histidine serves as the axial ligand to the Mg of bacteriochlorophylls in the photosynthetic reaction center (RC) and many other photosynthetic systems. The histidine axial ligands to each and both bacteriochlorophylls of the special-pair primary electron donor of the Rhodobacter sphaeroides RC have been replaced with glycine to create a cavity. In each case, RCs assemble and a normal special-pair comprised of Mg-containing bacteriochlorophylls is formed, as judged by many different spectroscopic and functional probes (e.g., absorption and Stark spectra, *P decay kinetics, P+Q(A)- recombination rate, and the redox potential of P). In contrast with heme proteins, where this strategy has been exploited to introduce exogenous organic ligands that can greatly affect the functional properties of the protein [DePillis, G. D., Decatur, S. M., Barrick, D., & Boxer, S. G. (1994) J. Am. Chem. Soc. 116, 6981-6982], addition of exogenous imidazole, pyridine, and ethanethiol has no measurable effect on the functional properties of the special pair in these cavity mutants. FT-Raman spectroscopy is used to provide more detailed information on local interactions around the special pair. Data in the core-size marker mode and carbonyl stretching region suggest that an adventitious ligand replaces histidine as the axial ligand to bacteriochlorophylls in the cavity mutants. We speculate that this ligand is water. Furthermore, the position of the core-size marker mode changes when the cavity mutant RCs are incubated with exogenous ligands such as imidazole, pyridine, or ethanethiol, suggesting that the axial ligand to the special pair BChls can be exchanged in the cavity mutants. Interestingly the temperature dependence of P+Q(A)- recombination kinetics is very similar in the cavity mutants and WT, suggesting that the axial ligands to the special pair are not significant contributors to the solvent reorganization energy for this reaction. These results lead to the surprising conclusion that the nature of the axial ligand to the special pair has little influence on the properties of the macrocycle, and that axial coordination from the protein by histidine is not required for bacteriochlorophyll binding or for efficient electron transfer in the RC.

Amino Acids↗
PubMed2006

Charge delocalization in the special-pair radical cation of mutant reaction centers of Rhodobacter sphaeroides from Stark spectra and nonadiabatic spectral simulations.

Stark and absorption spectra for the hole-transfer band of the bacteriochlorophyll special pair in the wild-type and L131LH, M160LH, and L131LH/M160LH mutants of the bacterial reaction center of Rhodobacter sphaeroides are presented, along with extensive analyses based on nonadiabatic spectral simulations. Dramatic changes in the Stark spectra are induced by the mutations, changes that are readily interpreted in terms of the redox-energy asymmetry and degree of charge localization in the special-pair radical cation. The effect of mutagenesis on key properties such as the electronic coupling within the special pair and the reorganization energy associated with intervalence hole transfer are determined for the first time. Results for the L131LH and M160LH/L131LH mutants indicate that these species can be considered as influencing the special pair primarily through modulation of the redox asymmetry, as is usually conceptualized, but M160LH is shown to develop a wide range of effects that can be interpreted in terms of significant mutation-induced structural changes in and around the special pair. The nonadiabatic spectra simulations are performed using both a simple two-state 1-mode and an extensive four-state 70-mode model, which includes the descriptions of additional electronic states and explicitly treats the major vibrational modes involved. Excellent agreement between the two simulation approaches is obtained. The simple model is shown to reproduce key features of the Stark effect of the main intervalence transition, while the extensive model quantitatively reproduces most features of the observed spectra for both the electronic and the phase-phonon regions, thus giving a more comprehensive description of the effect of the mutations on the properties of the special-pair radical cation. These results for a series of closely related mixed-valence complexes show that the Stark spectra provide a sensitive indicator for the properties of the mixed-valence complexes and should serve as an instructive example on the application of nonadiabatic simulations to the study of mixed-valence complexes in general as well as other chemical systems akin to the photosynthetic special pair.

Absorption↗
PubMed1996

Effects of Special Olympics International on social competence in persons with mental retardation.

OBJECTIVE: To evaluate the social and emotional goals of Special Olympics International, specifically whether Special Olympics facilitates social competence and self-esteem in persons with mental retardation. METHOD: Findings were "triangulated" across three studies on the social competence, adaptation, and self-perceptions of 104 athletes from 1993 Team USA (mean age = 22 years; mean IQ = 59). Study 1 related behavior to athletes' length of time in Special Olympics. Study 2 compared Team USA to an appropriately matched group of non-Special Olympians. Study 3 assessed Team USA before and 4 months after their participation in the World Games held in Salzburg, Austria. RESULTS: Relative to age and IQ, length of time in Special Olympics was the most powerful predictor of social competence. Special Olympics athletes had higher social competence scores and more positive self-perceptions than the comparison group. Team USA's behavioral data remained stable over time, suggesting that high pre-Game scores were not simply a function of parental or athlete pre-Game excitement. CONCLUSIONS: Based on the most conservative meaning of triangulation, more support was found linking Special Olympics to social competence than to remaining behavioral domains.

Adolescent↗
PubMed1998

The medical demands of the special athlete.

OBJECTIVE: To identify the most common injuries and medical conditions experienced by the mentally handicapped athlete during Special Olympic competition. DESIGN: A longitudinal, observational, and prospective study. SETTING: Hawaii Special Olympic Summer Games, 1993-1996. PARTICIPANTS: A total of 2326 athletic participants were registered during a 4-year period in the Hawaii Special Olympic Summer Games. The athletes ranged in age from 8 to 76 years. INTERVENTION: Medical encounter forms were documented by physicians and nurses on participants treated at aid stations located at the athletic venues and Olympic village during competition. MAIN OUTCOME MEASURES: The number and type of injuries and medical conditions encountered during Special Olympic competition were recorded on standard medical forms supplied by the U.S. Special Olympic Committee. RESULTS: Ninety athletes (3.87%) required medical attention during four annual Special Olympic Summer Games. A total of 52 (57.8%) injuries and 38 (42.2%) medical conditions were reported during the 4 years. Of the 90 encounters, 86.7% (n = 78) were acute and 13.3% (n = 12) were nonacute medical problems. More than 61% (n = 55) of the injuries and medical conditions occurred during actual competition. The majority of injuries occurred during track and field events (n = 25, 56%), and the most commonly injured site was the knee. CONCLUSIONS: Despite preexisting medical conditions and physical limitations of the Special Olympian, most of the medical demands encountered during athletic competition are acute, minor injuries. No athlete sustained more than one injury during the period studied.

Adolescent↗
PubMed2003

Facultative symbionts are associated with host plant specialization in pea aphid populations.

The pea aphid, Acyrthosiphon pisum, shows significant reproductive isolation and host plant specialization between populations on alfalfa and clover in New York. We examine whether specialization is seen in pea aphids in California, and whether fitness on alternative host plants is associated with the presence of bacterial symbionts. We measured the fitness of alfalfa- and clover-derived aphids on both types of plants and found no evidence for specialization when all aphid lineages were considered simultaneously. We then screened all aphids for the presence of four facultative bacterial symbionts: PAR, PASS, PABS and PAUS. Aphids with PAUS were host-plant specialized, having twice as many offspring as other aphids on clover, and dying on alfalfa. Other aphids showed no evidence of specialization. Additionally, aphids with PABS had 50% more offspring than aphids with PASS when on alfalfa. Thus, specialist and generalist aphid lineages coexist, and specialization is symbiont associated. Further work will resolve whether PAUS is directly responsible for this variation in fitness or whether PAUS is incidentally associated with host-plant specialized aphid lineages.

Adaptation, Physiological↗
PubMed2005

Economic evaluation of a general practitioner with special interests led dermatology service in primary care.

OBJECTIVE: To carry out an economic evaluation of a general practitioner with special interest service for non-urgent skin problems compared with hospital outpatient care. DESIGN: Cost effectiveness analysis and cost consequences analysis alongside a randomised controlled trial. SETTING: General practitioner with special interest dermatology service covering 29 general practices in Bristol. PARTICIPANTS: Adults referred to a hospital dermatology clinic who were potentially suitable for management by a general practitioner with special interest. INTERVENTIONS: Participants were randomised 2:1 to receive either care by general practitioner with special interest service or usual hospital outpatient care. MAIN OUTCOME MEASURES: Costs to NHS, patients, and companions, and costs of lost production. Cost effectiveness, using the two primary outcomes of dermatology life quality index scores and improved patient perceived access, was assessed by incremental cost effectiveness ratios and cost effectiveness acceptability curves. Cost consequences are presented in relation to all costs and both primary and secondary outcomes from the trial. RESULTS: Costs to the NHS for patients attending the general practitioner with special interest service were 208 pounds sterling (361 dollars; 308 euro) compared with 118 pounds sterling for hospital outpatient care. Based on analysis with imputation of missing data, costs to patients and companions were 48 pounds sterling and 51 pounds sterling, respectively; costs of lost production were 27 pounds sterling and 34 pounds sterling, respectively. The incremental cost effectiveness ratios for general practitioner with special interest care over outpatient care were 540 pounds sterling per one point gain in the dermatology life quality index and 66 pounds sterling per 10 point change in the access scale. CONCLUSIONS: The general practitioner with special interest service for dermatology is more costly than hospital outpatient care, but this additional cost needs to be weighed against improved access and broadly similar health outcomes.

Ambulatory Care↗
PubMed2005

Emerging neurophysiological specialization for letter strings.

In adult readers, printed words and other letter strings activate specialized visual functions within 200 msec, as evident from neurophysiological recordings of brain activity. These fast, specialized responses to letter strings are thought to develop through plastic changes in the visual system. However, it is unknown whether this specialization emerges only with the onset of word reading, or represents a precursor of literacy. We compared 6-year-old kindergarten children who could not yet read words to adult readers. Both age groups detected immediate repetitions of visually presented words, pseudowords, symbol strings, and pictures during event-related potential (ERP) mapping. Maps from seven corresponding ERP segments in children and adults were analyzed regarding fast (<250 msec) and slow (>300 msec) specialization for letter strings. Adults reliably differentiated words through increased fast (<150 msec) occipito-temporal N1 activity from symbols. Children showed a later, more mid-occipital N1 with marginal word-symbol differences, which were absent in those children with low letter knowledge. Children with high letter knowledge showed some fast sensitivity to letter strings, which was confined to right occipito-temporal sites, unlike the stronger adult N1 specialization. This suggests that a critical degree of early literacy induces some immature, but fast, specialization for letter strings before word reading becomes possible. Children also differentiated words from symbols in later segments through increased right occipito-temporal negativity for words. This slow specialization for letter strings was not modulated by letter knowledge and was absent in adults, possibly reflecting a visual precursor of literacy due to visual familiarity with letter strings.

Adult↗
PubMed2006

Measuring specialization in species interaction networks.

BACKGROUND: Network analyses of plant-animal interactions hold valuable biological information. They are often used to quantify the degree of specialization between partners, but usually based on qualitative indices such as 'connectance' or number of links. These measures ignore interaction frequencies or sampling intensity, and strongly depend on network size. RESULTS: Here we introduce two quantitative indices using interaction frequencies to describe the degree of specialization, based on information theory. The first measure (d') describes the degree of interaction specialization at the species level, while the second measure (H2') characterizes the degree of specialization or partitioning among two parties in the entire network. Both indices are mathematically related and derived from Shannon entropy. The species-level index d' can be used to analyze variation within networks, while H2' as a network-level index is useful for comparisons across different interaction webs. Analyses of two published pollinator networks identified differences and features that have not been detected with previous approaches. For instance, plants and pollinators within a network differed in their average degree of specialization (weighted mean d'), and the correlation between specialization of pollinators and their relative abundance also differed between the webs. Rarefied sampling effort in both networks and null model simulations suggest that H2' is not affected by network size or sampling intensity. CONCLUSION: Quantitative analyses reflect properties of interaction networks more appropriately than previous qualitative attempts, and are robust against variation in sampling intensity, network size and symmetry. These measures will improve our understanding of patterns of specialization within and across networks from a broad spectrum of biological interactions.

Adaptation, Physiological↗
PubMed2000

Access to health care for children with special health care needs.

OBJECTIVE: To assess the role health insurance plays in influencing access to care and use of services by children with special health care needs. METHODS: We analyzed data on 57 553 children younger than 18 years old included in the 1994-1995 National Health Interview Survey on Disability. The survey obtained information on special health care needs, insurance status, and access to and use of health services. Bivariate and multivariate analyses were used to assess the association of insurance with several measures of access and utilization, including usual source of care, site of usual care, missed or delayed care, and use of ambulatory physician services. RESULTS: Using the federal Maternal and Child Health Bureau definition of children with special health care needs, we estimate that 18% of US children under 18 years old had an existing special health care need in 1994-1995. An estimated 89% of these children had some form of health insurance coverage, most often private health insurance. Insured children were more likely than uninsured children to have a usual source of care (96.9% vs 79.2%). Among those with a usual source of care, insured children were more likely than uninsured children to have an identified regular clinician (87. 6% vs 80.7%). Insured children were less likely to report unmet health needs, including medical care (2.2% vs 10.5%), dental care (6. 1% vs 23.9%), prescriptions, and/or eyeglasses (3.1% vs 12.3%), and mental health care (.9% vs 3.4%). Insured children were also more likely to have a physician contact in the past year (89.3% vs 73.6%) and have more physician contacts on an annual basis (8.5 vs 4.1 contacts). Unexpectedly, no differences were found between insured and uninsured children in availability of after hours medical care (evenings and weekends) or satisfaction with care. We also found some modest differences in access between publicly and privately insured children. Privately insured children were more likely to have a usual source of care (97.6% vs 95.3%) and a regular clinician (91.0% vs 81.1%). Privately insured children were also less likely to report dissatisfaction with care at their usual site of care (14. 9% vs 21.0%) and have access to care on evenings and weekends (6.8% vs 13.4%). No substantial differences were found between privately and publicly insured children in prevalence of unmet health needs or delays in obtaining care due to cost. CONCLUSIONS: This study illustrates the importance of health insurance for children with special health care needs. Continued efforts are needed to ensure that all children with special health care needs have insurance and that remaining access and utilization barriers for currently insured children with special health care needs are also addressed.

Adolescent↗
PubMed2006

Children at risk for special health care needs.

OBJECTIVE: Despite the widespread use of the Maternal and Child Health Bureau definition of children with special health care needs, no published studies have considered the "at-risk" component of the definition. The purpose of this article is to present a conceptual model of risk for special health care needs. METHODOLOGY: The conceptual model presented here was developed based on a comprehensive review of the literature on the determinants of population health and the etiologic literature for selected representative childhood chronic conditions. RESULTS: Our conceptual model is built on 5 key pillars derived from the literature. First, determinants of health have been demonstrated to include genetic endowment, the physical and social environment, health-related behaviors, and the health care system. Second, the model recognizes that the relative importance of each of these domains in contributing to the presence of a special health care need is likely to vary across the major chronic conditions experienced by children. Third, these domains can be conceptualized as acting at the child, family, community, or societal level. Fourth, the model recognizes the presence of a complex interplay of causal factors influencing the development of chronic conditions and associated special health care needs. Fifth, the model incorporates a temporal aspect to the development of special health care needs. CONCLUSIONS: The conceptual model presented here represents a starting point for thinking about the risk factors that influence the occurrence and severity of a special health care need. The model incorporates many of the important breakthroughs by social epidemiologists over the past 25 years by including a broad range of genetic, social, and environmental risk factors; multiple pathways by which they operate; a time dimension; the notion of differential susceptibility and resilience; and a multilevel approach to considering risk. Nevertheless, we recognize that the conceptual model represents an oversimplification of reality. The study of risk factors for special health care needs remains largely in its infancy and is ripe for additional development.

Child↗