Molecular Biology to Radiation Oncology: A Model for Translational Research? Opportunities in basic and translational research. From a workshop sponsored by the National Cancer Institute, Radiation Research Program, January 26-28, 1997, Bethesda, Maryland

Many exciting discoveries are being made that are providing new insights into how molecules, cells and tissues respond to ionizing radiation. There remains a need, however, to translate these findings into more effective treatments for cancer patients, including those treated with radiation therapy. This complex task will require the collaboration of scientists studying molecular, cellular and tissue responses, and those performing clinical trials of emerging therapies. The Radiation Research Program of the National Cancer Institute sponsored a workshop entitled "Molecular Biology to Radiation Oncology: A Model for Translational Research?" to bring together basic scientists and clinicians to exchange ideas and fundamental concepts and to identify opportunities for future research and collaboration. Four broad topics were addressed: signal transduction and apoptosis, the cell cycle, repair of radiation damage, and the microenvironment. The development, selection and use of appropriate experimental models is crucial to finding and developing new therapies, and opportunities exist in this area as well. This paper and the accompanying paper by Coleman and Harris that provides the viewpoint of radiation oncologists (Radiat. Res. 150, 134-147, 1998) summarize the background concepts and opportunities for translational research identified by the workshop participants.     

Chronic electrical stimulation of the left ventrointermediate (Vim) thalamic nucleus for the treatment of pharmacotherapy-resistant Parkinson's disease: a differential impact on access to semantic and episodic memory?

Thalamotomy for medically refractory Parkinson's disease (PD) is considered to be efficacious and relatively safe. Because a minority of patients experience decrements in language and memory (often mild and transient) after thalamotomy, chronic thalamic deep brain stimulation (DBS) might be a safer treatment given its reversibility and the modifiability of stimulation parameters. Two preliminary studies support the relative cognitive safety of unilateral DBS of the ventral intermediate (Vim) thalamic nucleus, but it is unclear whether possibly subtle changes in language and memory represent effects of "microthalamotomy" or of stimulation per se. This report provides preliminary data concerning effects of left thalamic stimulation on information processing speed, semantic memory (verbal fluency and visual confrontation naming), and verbal episodic memory in a patient with PD. In addition to being evaluated before and 3 and 6 months after surgery, the patient was tested 18 months after surgery either on or off medications and with the stimulator turned either on or off (order counterbalanced across medication conditions). Test performance differences between the stimulation conditions were attenuated "off" as compared to "on" medication. Vim stimulation consistently, albeit subtly, improved semantic verbal fluency but interfered with immediate recall of word lists. Parallels to findings from acute, intraoperative thalamic stimulation studies are explored. The hypothesis is offered that left Vim stimulation might facilitate access to semantic memory, but interfere with episodic memory processes.     

Strategies for rare-event detection: an approach for automated fetal cell detection in maternal blood

This article explores the feasibility of the use of automated microscopy and image analysis to detect the presence of rare fetal nucleated red blood cells (NRBCs) circulating in maternal blood. The rationales for enrichment and for automated image analysis for "rare-event" detection are reviewed. We also describe the application of automated image analysis to 42 maternal blood samples, using a protocol consisting of one-step enrichment followed by immunocytochemical staining for fetal hemoglobin (HbF) and FISH for X- and Y-chromosomal sequences. Automated image analysis consisted of multimode microscopy and subsequent visual evaluation of image memories containing the selected objects. The FISH results were compared with the results of conventional karyotyping of the chorionic villi. By use of manual screening, 43% of the slides were found to be positive (>=1 NRBC), with a mean number of 11 NRBCs (range 1-40). By automated microscopy, 52% were positive, with on average 17 NRBCs (range 1-111). There was a good correlation between both manual and automated screening, but the NRBC yield from automated image analysis was found to be superior to that from manual screening (P=.0443), particularly when the NRBC count was >15. Seven (64%) of 11 XY fetuses were correctly diagnosed by FISH analysis of automatically detected cells, and all discrepancies were restricted to the lower cell-count range. We believe that automated microscopy and image analysis reduce the screening workload, are more sensitive than manual evaluation, and can be used to detect rare HbF-containing NRBCs in maternal blood.     

Transparent High-Performance Supramolecular Plastics Operating in All-Weather Environments

Supramolecular plastics (SMPs) can be made mechanically robust, repairable, and recyclable, rendering themselves promising alternatives to their conventional predecessors to address environmental concerns. However, dense accumulations of noncovalent bonds generally lead to mechanical brittleness as well as intolerance toward heat and moisture. To resolve this issue, a simple strategy of preparing high-performance SMP by constructing highly dense, but irregular hydrogen-bond networks with hierarchical structures is proposed. The resultant SMP exhibits an outstanding combination of good comprehensive mechanical properties (high stiffness, strength, and toughness with ductile failure when fracturing), excellent dynamic behaviors (repairability and recyclability), and high tolerances toward moisture and high temperatures (as high as 90 °C). Additionally, the SMP also shows a high dielectric constant, exhibiting great potential for applications such as healable flexible touch screens and energy storage. Last, through structure characterizations and molecular dynamic simulation, this study provides a fundamental insight into the mechanism behind such high-performances from nano- to micro-scales, which is expected to inspire the design of a wide range of other SMPs that use different chemistries.     

Meltblown fabric vs nanofiber membrane,which is better for fabricating personal protective equipments

The coronavirus disease 2019 (COVID-19) pandemic has led to a great demand on the personal protection products such as reusable masks.As a key raw material for masks,meltblown fabrics play an important role in rejection of aerosols.However,the electrostatic dominated aerosol rejection mechanism of melt-blown fabrics prevents the mask from maintaining the desired protective effect after the static charge degradation.Herein,novel reusable masks with high aerosols rejection efficiency were fabricated by the introduction of spider-web bionic nanofiber membrane (nano cobweb-biomimetic membrane).The reuse stability of meltblown and nanofiber membrane mask was separately evaluated by infiltrating water,75％ alcohol solution,and exposing under ultraviolet (UV) light.After the water immersion test,the filtration efficiency of meltblown mask was decreased to about 79％,while the nanofiber membrane was maintained at 99％.The same phenomenon could be observed after the 75％ alcohol treatment,a high filtration efficiency of 99％ was maintained in nanofiber membrane,but obvious negative effect was observed in meltblown mask,which decreased to about 50％.In addition,after long-term expose under UV light,no filtration efficiency decrease was observed in nanofiber membrane,which provide a suitable way to disinfect the potential carried virus.This work successfully achieved the daily disinfection and reuse of masks,which effectively alleviate the shortage of masks during this special period.     

蓝晶石微粉的烧结性能及其机理

介绍了蓝晶石微粉的烧结性能 ,并对其烧结机理进行了探讨。在 1 0 0 0～ 1 40 0℃以不同温度煅烧 ,微粉坯体呈收缩状态 ,线变化率为- 0 .83%～ - 2 .1 6% ,体积密度为 1 .99～ 2 .1 1g·cm- 3,显气孔率为 2 0 %～ 2 3% ,常温耐压强度为1 63～ 2 64MPa。烧结温度以 1 1 50～ 1 2 0 0℃最佳。与普通蓝晶石精矿粉相比 ,微粉不仅能显著提高制品的机械强度 ,还可明显降低制品的烧结温度。     

丙烯酸酯乳液的改性研究与发展状况

丙烯酸酯乳液是一大类容易制备、性能优良、价格低廉、应用广泛,且符合环保要求的聚合物.丙烯酸酯乳液的改性研究已经得到了多方面的发展.介绍了丙烯酸酯乳液的基本特性,分析了有机硅、有机氟、聚氧酯和环氧树脂改性丙烯酸酯乳液的优缺点,综述了其改性方法及研究现状,对今后丙烯酸酯乳液改性的发展提出了建议.     

桃园煤矿瓦斯抽放参数优化研究

应用采空区顶板冒落的关键层理论，确定了桃园煤矿裂隙带的高度，为优化采空区顶板抽放参数提供了依据，并利用优化设计的高位钻孔进行瓦斯抽放，回风巷和上隅角的瓦斯浓度均得到控制，消除了瓦斯超限现象，保证了工作面的安全回采。