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Four novel alkyl 2-cyanoacrylate monomers (alkyl=1-cyanoethyl, 2-cyanoethyl, trideuteromethyl and pentadeuteroethyl) have been tested for their ability to develop latent fingermarks that can then be visualized using mid-infrared spectral (chemical) imaging. Each of the four monomers was chosen for its potential to produce a strong, isolated infrared spectral band in its corresponding polymer (to provide spectral contrast against most backgrounds), as well as for its potential ability to be fumed onto fingermarks in the manner of conventional ethyl 2-cyanoacrylate (superglue). With the exception of the 2-cyanoethyl 2-cyanoacrylate, which had to be fumed under reduced pressure, all of the monomers were found to be sufficiently volatile to be fumed in a conventional fuming cabinet. All four monomers polymerized selectively on fingermark ridges on a variety of non-porous and semi-porous surfaces, leading to excellent development of the fingermarks. Unfortunately, although high quality mid-infrared spectral images of the fingermarks could be formed for all of the polymers at various frequencies, the new CN or CD stretching vibrations did not give rise to strong enough absorption intensities for good contrast on difficult backgrounds such as polymer banknotes. However, in the 1-cyanoethyl 2-cyanoacrylate polymer, the presence of the additional nitrile group had the unintended but desirable effect of shifting the strong CO absorption to higher frequencies, moving it away from interfering banknote absorptions. This enabled fingermark contrast to be achieved even against the intaglio printing on the banknotes.  相似文献   
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This article provides a nationally representative profile of noninstitutionalized children 0 to 17 years of age who were receiving support from the Supplemental Security Income (SSI) program because of a disability. To assess the role of the SSI program in providing assistance to low-income children with disabilities and their families, it is important to obtain detailed information on demographic characteristics, income and assets, health and disabilities, and health care utilization. Yet administrative records of the Social Security Administration do not contain many of the relevant data items, and the records provide only an incomplete picture of the family relationships affecting the lives of children with disabilities. The National Survey of SSI Children and Families fills this gap. This summary article is based on survey interviews conducted between July 2001 and June 2002 and provides some highlights characterizing children with disabilities who were receiving SSI and their families. Most children receiving SSI (hereafter referred to as "SSI children") lived in a family headed by a single mother, and less than one in three lived with both parents. A very high proportion, about half, were living in a household with at least one other individual reported to have had a disability. About 70 percent of children received some kind of special education. SSI support was the most important source of family income, with earnings a close second. On average, SSI payments accounted for nearly half of the income for the children's families, and earnings accounted for almost 40 percent. When all sources of family income were considered, slightly more than half (54 percent) of SSI children lived in families above the poverty threshold, a notable fact given that the federal SSI program guarantees only a subpoverty level of income. However, beyond these averages there was substantial variation, with some children living in families with income well below the poverty threshold and others having income well over 200 percent of the poverty threshold. About one-third of SSI children lived in families owning a home, two-thirds lived with parents or guardians with at least one car, and about 40 percent lived with parents or guardians with zero liquid assets. Less than 4 percent lived with adults who owned stocks, mutual funds, notes, certificates of deposit, or savings bonds. The Social Security Administration's administrative records contain only a limited amount of information about disability diagnoses. The National Survey of SSI Children and Families supplements those records with data from an array of questions on functional limitations, self-reported health, and the perceived severity of disabilities. The data suggest that a great degree of variation in severity exists within the childhood caseload, as reflected in reports of the presence or absence of six functional limitations, perceived overall health status, and perceived impact of disability on the child's ability to do things. Overall, 36 percent of the children were reported to have had disabilities that affected their abilities to do things "a great deal," and for 21 percent their difficulties had very little or no impact. Physical disabilities were most common among children aged 0 to 5, and mental disabilities dominated the picture for the other two age groups: 6 to 12 and 13 to 17. Virtually all SSI children are covered by some form of health insurance, with Medicaid being by far the most common source of health insurance coverage. Just as in the case of the severity of disabilities, substantial variation was reported in health care utilization among SSI children. Almost 30 percent of children had two or fewer doctor visits during the 12 months preceding the interview, and close to 50 percent had five or more doctor visits. About four-fifths of the children had no reported hospitalizations or surgeries during the previous year. More than 40 percent of the children visited an emergency room during the previous year, most of them more than once. Importantly, no out-of-pocket costs associated with medical care were reported for more than two-thirds of the children, and only about 3 percent had annual expenses exceeding $1,000 for physical and mental health care. This finding suggests that SSI payments are not used to cover medical expenses for the overwhelming majority of children. The use of supportive therapies varied widely among SSI children: more than half reported having used physical, occupational, or speech therapy; only 8 percent used respite care for the parents or other family members. An analysis of the perception of the survey respondents shows that more than one-third of children had unmet needs for mental health counseling services, and about three-quarters of families had unmet needs for respite care. In several service categories, the proportion perceived to have had unmet service needs was around 10 percent or less. In the dominant service category of physical, occupational, and speech therapy, only 11 percent perceived to have had unmet service needs.  相似文献   
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