机构输入与识别系统的研究——机构创新设计系统研究之三

介绍了机构创新设计系统以两种方式输入简图作为构型设计的原形。一种是在系统界面环境直接点击专用菜单绘制简图；一种方式是由设计者提供手绘草图或图纸，通过图像处理和模式识别技术，实现草图的获取，转化为系统机构绘制单元组成的简图。机构生成模块对简图可以进行自动识别纠错，保证机构的合理性，得到完整的机构信息。机构输入系统的实现，奠定了机构创新设计的自动化、智能化基础。     

Assessing the date of the global oil peak: The need to use 2P reserves

Combining geological knowledge with proved plus probable (‘2P’) oil discovery data indicates that over 60 countries are now past their resource-limited peak of conventional oil production. The data show that the global peak of conventional oil production is close.

Many analysts who rely only on proved (‘1P’) oil reserves data draw a very different conclusion. But proved oil reserves contain no information about the true size of discoveries, being variously under-reported, over-reported and not reported. Reliance on 1P data has led to a number of misconceptions, including the notion that past oil forecasts were incorrect, that oil reserves grow very significantly due to technology gain, and that the global supply of oil is ensured provided sufficient investment is forthcoming to ‘turn resources into reserves’. These misconceptions have been widely held, including within academia, governments, some oil companies, and organisations such as the IEA.

In addition to conventional oil, the world contains large quantities of non-conventional oil. Most current detailed models show that past the conventional oil peak the non-conventional oils are unlikely to come on-stream fast enough to offset conventional's decline. To determine the extent of future oil supply constraints calculations are required to determine fundamental rate limits for the production of non-conventional oils, as well as oil from gas, coal and biomass, and of oil substitution. Such assessments will need to examine technological readiness and lead-times, as well as rate constraints on investment, pollution, and net-energy return.     

Icons improve older and younger adults' comprehension of medication information

We examined whether timeline icons improved older and younger adults' comprehension of medication information. In Experiment 1, comprehension of instructions with the icon (icon/text format) and without the icon (text-only format) was assessed by questions about information that was (a) implicit in the text but depicted explicitly by the icon (total dose in a 24 hour period), (b) stated and depicted in the icon/text condition (medication dose and times), and (c) stated but not depicted by the icon (e.g., side effects). In a separate task, participants also recalled medication instructions (with or without the icon) after a study period. We found that questions about dose and time information were answered more quickly and accurately when the icon was present in the instructions. Notably, icon benefits were greater for information that was implicit rather than stated in the text. This finding suggests that icons can improve older and younger adults' comprehension by reducing the need to draw some inferences. The icon also reduced effective study time (study time per item recalled). In Experiment 2, icon benefits did not occur for a less integrated version of the timeline icon that, like the text, required participants to integrate dose and time information in order to identify the total daily dose. The integrated version of the icon again improved comprehension, as in Experiment 1, as well as drawing inferences from memory. These findings show that integrated timeline icons improved comprehension primarily by aiding the integration of dose and time information. These findings are discussed in terms of a situation model approach to comprehension.     

Definition of natural T cell antigens with mimicry epitopes obtained from dedicated synthetic peptide libraries

Progress has recently been made in the use of synthetic peptide libraries for the identification of T cell-stimulating ligands. T cell epitopes identified from synthetic libraries are mimics of natural epitopes. Here we show how the mimicry epitopes obtained from synthetic peptide libraries enable unambiguous identification of natural T cell Ags. Synthetic peptide libraries were screened with Mycobacterium tuberculosis-reactive and -autoreactive T cell clones. In two cases, database homology searches with mimicry epitopes isolated from a dedicated synthetic peptide library allowed immediate identification of the natural antigenic protein. In two other cases, an amino acid pattern that reflected the epitope requirements of the T cell was determined by substitution and omission mixture analysis. Subsequently, the natural Ag was identified from databases using this refined pattern. This approach opens new perspectives for rapid and reliable Ag definition, representing a feasible alternative to the biochemical and genetic approaches described thus far.     

Pattern formation in chick feather development: distribution of beta 1-integrin in normal and scaleless embryos

We have examined the immunolocalization of beta 1-integrin during feather development in the spino-lumbar tract of the backskin from normal and scaleless chick embryos. beta 1-integrin appears during early feather development in three distinct phases which correspond to important developmental events. The first phase (5-5 1/2 days of incubation; Hamburger and Hamilton [H.H.] stage 27) represents the period prior to the formation of dermis. During this phase, beta 1-integrin antiserum labels mesenchymal cells located in the central region of the spino-lumbar tract where the initiation site for feather development is located. The second phase (5 1/2-7 1/2 days of incubation; H.H. stages 28-32) corresponds to the period during which dermis is formed. The cells that make up the dermis are readily distinguished by their lack of beta 1-integrin immunostaining. The third phase (7 1/2-10 days of incubation; H.H. stages 33-36) begins with the sudden appearance of beta 1-integrin in the central and lateral regions of the dermis. The pattern of beta 1-integrin immunostaining in scaleless backskin becomes different from that of normal backskin during this phase. In normal backskin the dermal condensations of feather germs are not labeled with the beta 1-integrin antiserum. This produces a heterogeneous immunostaining pattern very similar to the pattern seen for Type I collagen (Mauger et al. [1982] Dev. Biol. 94:93-105). In contrast, homogeneous immunostaining is observed in the dermis of scaleless backskin. The initial time of appearance, manner of appearance, and pattern of integrin expression in the third phase suggest that beta 1-integrin may be involved in the stabilization of the feather pattern. We also observed the appearance of beta 1-integrin on the epidermal basal cells during the time of feather follicle formation. The beta 1-integrin antiserum reacts strongly with the baso-lateral surfaces of normal basal cells, yet the basal surfaces of the scaleless basal cells are unstained. This lack of immunostaining along the basal surfaces of the scaleless basal cells may relate to the abnormal adhesion between the epidermis and dermis in scaleless backskin.     

Outcome of patients with total colonic ischemia

PURPOSE: In this study, we sought to determine the outcome of patients with ischemic colitis, comparing patients with segmental disease with those with total colonic ischemia. METHODS: Patients with the diagnosis of ischemic colitis over the past six years were selected and reviewed for demographics, presenting symptoms, diagnosis, and treatment. RESULTS: Forty-three consecutive patients with ischemic colitis were identified and were grouped into those with segmental ischemic colitis and total colonic ischemia. Mean age was 68.8 years; 28 of 43 patients (65 percent) were males. Diagnosis was established by colonoscopy in 31 of 43 patients (72 percent), whereas in the remainder, diagnosis was made in the operating room. Ischemic colitis developed in the hospital in 17 of 43 patients (40 percent) during admission for an unrelated illness. In 6 of 43 (14 percent) of these patients, ischemic colitis developed following surgery. Thirty-one of 43 patients (72 percent) were found to have segmental colitis; 11 of 31 patients (35 percent) were successfully managed nonoperatively. Segmental colitis was present in 31 of 43 patients (72 percent), and 12 of 31 (35 percent) of these patients were successfully managed nonoperatively. In the patients with segmental colitis who required surgery, the 30-day mortality rate was 22 percent. Among 12 of 17 patients (71 percent) with segmental ischemia treated by resection and stoma, 9 of 12 (75 percent) underwent eventual stoma closure. All 12 patients with total colonic ischemia required surgery, and 9 of 12 patients (75 percent) died. CONCLUSION: Ischemic colitis occurs commonly during an unrelated hospital admission and following previous surgery. Most patients treated by resection and stoma undergo stoma closure. Total colonic ischemia carries a worse prognosis than segmental colonic ischemia.     

1,4-Cyclohexanecarboxylates: potent and selective inhibitors of phosophodiesterase 4 for the treatment of asthma

Evaluation of a variety of PDE4 inhibitors in a series of cellular and in vivo assays suggested a strategy to improve the therapeutic index of PDE4 inhibitors by increasing their selectivity for the ability to inhibit PDE4 catalytic activity versus the ability to compete for high affinity [3H]rolipram-binding sites in the central nervous system. Use of this strategy led ultimately to the identification of cis-4-cyano-4-[3-(cyclopentyloxy)-4-methoxyphenyl]cyclohexane-1-carboxyl ic acid (1, SB 207499, Ariflo), a potent second-generation inhibitor of PDE4 with a decreased potential for side effects versus the archetypic first generation inhibitor, (R)-rolipram.     

Use of Percoll gradient centrifugation for the isolation of diatoms from Wadden Sea sediments; diatom yields, species recoveries and population diversity

Platelet-activating factor (PAF) production is carefully controlled in inflammatory cells. The specific removal of arachidonate (AA) from 1-O-alkyl-2-arachidonoyl-sn-glycero-3-phosphocholine (GPC), thought to be mediated by CoA-independent transacylase (CoA-IT), is required to generate the PAF precursor 1-O-alkyl-2-lyso-GPC in human neutrophils. Exposure of A23187-stimulated human monocytes to the CoA-IT inhibitors SK&F 98625 and SK&F 45905 inhibited PAF formation (IC50s of 10 and 12 microM, respectively), indicating that these cells also need CoA-IT activity for PAF production. Because CoA-IT activity transfers arachidonate to a 2-lyso phospholipid substrate, its activity is obligated to an sn-2 acyl hydrolase to form the 2-lyso phospholipid substrate. SB 203347, an inhibitor of 14 kDa phospholipase A2 (PLA2), and AACOCF3, an inhibitor of 85 kDa PLA2, both inhibited AA release from A23187-stimulated human monocytes. However, AACOCF3 had no effect on A23187-induced PAF formation at concentrations as high as 3 microM. Further, depletion of 85 kDa PLA2 using antisense (SB 7111, 1 microM) had no effect on PAF production, indicating a lack of a role of 85 kDa PLA2 in PAF biosynthesis. Both SB 203347 and the 14 kDa PLA2 inhibitor scalaradial blocked PAF synthesis in monocytes (IC50s of 2 and 0.5 microM, respectively), suggesting a key role of 14 kDa PLA2 in this process. Further, A23187-stimulated monocytes produced two forms of PAF: 80% 1-O-alkyl-2-acetyl-GPC and 20% 1-acyl-2-acetyl-GPC, which were both equally inhibited by SB 203347. In contrast, inhibition of CoA-IT using SK&F 45905 (20 microM) had a greater effect on the production of 1-O-alkyl (-80%) than of 1-acyl (-14%) acetylated material. Finally, treatment of U937 cell membranes with exogenous human recombinant (rh) type II 14 kDa PLA2, but not rh 85 kDa PLA2, induced PAF production. Elimination of membrane CoA-IT activity by heat treatment impaired the ability of 14 kDa PLA2 to induce PAF formation. Taken together, these results suggest that a 14 kDa PLA2-like activity, and not 85 kDa PLA2, is coupled to monocyte CoA-IT-induced PAF production.