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101.
An innovative TPO, based upon a complex fluid, is described, which shows an unusual balance of physical properties. The effects of complex fluid composition are addressed in a statistically designed experiment. Physical performance, rheological effects, thermal analysis, and morphological characterization are reported. J. VINYL ADDIT. TECHNOL., 12:183–191, 2006. © 2006 Society of Plastics Engineers  相似文献   
102.
By a strategy suggested by E. H. Uhlenhuth et al (1983), Diagnostic and Statistical Manual of Mental Disorders (DSM-III) referenced syndrome classifications were derived on the basis of the Hopkins Symptoms Checklist—42 scores of 1,131 elderly community residents. Overall syndrome prevalence rates were consistent with other epidemiologic data: 3.9% for depression, 1.0% for agoraphobia-panic, 2.6% for other phobia, and 6.9% for anxiety. Prevalence rates reflected expected sex differences and showed an age trend for other phobias. Considerable comorbidity among syndromes was observed. The association of the syndromes with patterns of psychosocial risk factors, prior diagnoses, and medication suggests that some but not all of the identified syndromes reflect clinically relevant classifications. If further developed, syndrome classifications based on self-report scales can provide inexpensive and clinically relevant measures of caseness. Required refinements of this approach are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
103.
王云  王德安 《光电工程》1992,19(6):61-63
热成像系统检测仪器的定标工作直接影响着热像仪MTF数据的可信度。本文描述从英国Sira公司引进的微机控制红外和可见光系统MTF检测仪器的FTF校准工作,介绍了测量原理、校正程序,给出了实测数据及仪器误差值,最后对校正结果进行了讨论。  相似文献   
104.
105.
The density of GABA(A) receptors in the hippocampus and the temporal cortex from rats treated for 28 days with either haloperidol, chlorpromazine, clozapine or olanzapine was measured. Compared to haloperidol (0.01 and 0.1 mg kg(-1) day(-1)) and chlorpromazine (0.1 and 1 mg kg(-1) day(-1)), clozapine and olanzapine (0.1 and 1 mg kg(-1) day(-1)) markedly decreased the density of GABA(A) receptors in these two brain regions. These data suggest that modulation of GABAergic transmission could be an important action of some antipsychotic drugs.  相似文献   
106.
Adult cat fleas, Ctenocephalides felis (Bouché), were fed suboptimal in vitro concentrations of lufenuron in blood to allow hatching of flea larvae for cytological study. At concentrations of 0.125, 0.25, and 0.5 ppm, larval hatch was 64, 15, and 4%, respectively. Larvae hatching from eggs laid by adults fed lufenuron at concentrations of 0.025, 0.08, or 0.125 ppm did not differ significantly from the control. However, many larvae from the 0.08-ppm group and higher concentrations died during the 1st instar. Examination of these larvae revealed that they were dying from desiccation caused by bleeding from microscopic lesions in the cuticle or the inability to complete the molt to the next instar. Electron micrographs showed that lufenuron often disrupted formation of the endocuticle resulting in the deposition of an amorphous mass of randomly oriented chitin microfibrils. Other larvae formed normal endocuticle but were unable to digest the old endocuticle or produce new procuticle after apolysis. Failure of larvae to digest old cuticle or form new cuticle was caused by degeneration of the epidermal cells needed for the synthesis of molting fluid and chitin.  相似文献   
107.
A 64 year old woman presented with persistent and severe symptoms due to recurrent aspiration pneumonias associated with oesophageal reflux. She had had multiple miscarriages and her son at birth had widely spaced eyes (hypertelorism), hypospadias, bilateral undescended testes, and an imperforate anus. Her daughter has mild hypertelorism and her daughter's son had neonatal inspiratory stridor, hypospadias and hypertelorism, all features now recognised as typical of the Opitz oculo-genito-laryngeal syndrome. This syndrome is genetically heterogeneous with autosomal dominant (linked to chromosome 22q21) and X-linked (linked to Xp22) inheritance. This family's history and genetic linkage data are consistent with linkage to Xp22. The proband is a manifesting carrier of this syndrome; her history of recurrent aspiration is probably secondary to pharyngeal neuromuscular incoordination aggravating gastro-oesophageal reflux. Obtaining a family history gives a vital clue to the diagnosis of Opitz oculo-genito-laryngeal syndrome. It is also suggested that this condition should be included in the differential diagnosis of recurrent aspiration pneumonia.  相似文献   
108.
The efficacy of nonreamed nailing as the treatment of choice of unstable blunt tibial diaphyseal fractures was studied. From March 1, 1990, through August 31, 1991, 72 patients with 74 fractures that required fixation were treated. One patient died and six were lost to follow-up, leaving 65 patients with 67 fractures. Follow-up averaged 21 months (range 5-43). Fisher's exact and logistic regression analyses were used to compare grades of open fractures, comminution as classified by Winquist, and dynamic and static nailings. The failure rates of 51 titanium and 16 stainless steel nails were compared. Times to union were compared by the log rank statistic method. The average time to union was 32 weeks with 26 (39%) additional operations required to achieve union; 13 dynamizations (12 successful), 12 exchange nailings (11 successful), and one plate and bone graft. The rate of reconstructive procedures to achieve union was a more sensitive indicator of difficulties achieving union than was time to union. Reoperation rates were 33% for closed or grade I and II fractures compared with 46% for grade III fractures (NS). Among closed grade I and II static versus dynamic nailing, times to union were 36 versus 25 weeks (p < 0.01), and the reoperation rates were 44% versus 13% (p < 0.04). Winquist I and II fractures required a 24% reoperation rate versus 53% for grade III and IV and segmental fractures (p < 0.01). Static locked fractures required a 48% reoperation rate versus 12% for dynamic locked fractures (p < 0.01). A logistic regression analysis demonstrated that locking mode was the most important factor in determining reoperation rates. Fifteen additional reoperations for infection, broken or painful implants, or to remodel bones that united with an incomplete circumference of cortex were performed. With an additional 12 elective nail removals, the total reoperations numbered 53 (79%). Titanium alloy nails had a 2% failure rate versus 25% for stainless steel nails (p < 0.01). Two of 28 (7%) grade III fractures became infected. All fractures united within 10 degrees of normal alignment and 1 cm of length. Nine (13%) united with an incomplete cortical circumference, refractory to dynamization and full weight bearing. Thirteen of the 58 (22%) fractures available for an evaluation of ankle motion were symptomatic, with < 10 degrees of dorsiflexion.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
109.
Investigated 2 independent variables associated with the design of instruction for coordinate concept learning to clarify the transition in memory between conceptual knowledge formation and procedural knowledge development. The 1st variable, display time interval, controlled the amount of instructional display time of each interrogatory example; the 2nd variable, content sequence, sequenced examples according to response-sensitive decision strategies effecting incorrect solutions. 72 11th graders who were randomly assigned to 1 of 6 instructional treatment conditions served as Ss in a 2?×?3 experimental design. Data analysis showed that adaptive-controlled display time groups needed fewer examples and less instructional time and performed better on the posttest and retention test than did the learner-controlled groups. For the 2nd variable, the combined generalization–discrimination strategy resulted in better on-task learning efficiency and test performances than each of these strategies separately. Findings are discussed in reference to concept teaching using a 2-phase concept-learning theory. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
A generalization of the data parallel model has been proposed by Blelloch which permits the nesting of data parallel operators to specify parallel computation across nested and irregular data structures. In this paper we consider the costs of supporting the general model of nested data parallelism, analyzing the requirements such a model places upon an underlying model of execution. We propose a new multi-node execution model which meets the needs of the paradigm and is additionally generic in the partitioning of data aggregates within the system. The basis for our execution model is an abstract machine based upon elementary notions of nodal multi-threading. We demonstrate the utility of our proposal by providing a full definition for a simple nestable one-dimensional data parallel operator. We discuss the applicability of our design to existing multi-processor machines, illustrating performance statistics gathered from a prototype system we have constructed on the Thinking Machines CM-5.  相似文献   
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