Chemical Classification of Space Debris

Space debris, here referring to all non-operating orbital objects, has steadily increased in number so that it has become a potential barrier to the exploration of space. The ever-increasing number of space debris pieces in space has created an increasingly threatening hazard to all on-the-orbit spacecraft, and all future space exploration activities have to be designed and operated with respect to the increasing threat posed by space debris. Generally, space debris is classified as large, medium and small debris pieces based on their sizes. The large debris piece is easily catalogued, but medium to small debris pieces are very difficult to track and also quite different in damage mechanisms from the large ones. In this paper, a scheme of chemical classification of space debris is developed. In our scheme, the first-order classification is employed to divide space debris into two groups: natural micrometeoroids and artificial space debris. The second-order classification is based on their chemical patterns and compositions. The natural micrometeoroids are further divided into three types, namely mafic, metal and phyllosilicate micrometeorites, while the artificial space debris is divided into seven types, which are polymers, non-metal debris, metals and their alloys, oxides, sulphides and their analogs, halides and carbides. Of the latter seven types, some can also be further divided into several sub-types. Chemical classification of space debris is very useful for the study of the chemical damage mechanism of small debris pieces, and also is of great significance in constraining the origin and source of space debris and assessing their impact on spacecraft and human space activities.

The Chemical Classification of the AGB Star IRAS 17515-2407

The chemical classification of IRAS 17515-2407 has been debated for a longtime. Up to now there are two contenders, oxygen-rich or carbon-rich. We believe that IRAS17515-2407 is an oxygen-rich source: because (ⅰ) it shows the silicate self-absorbed emission; (ⅱ)in the near infrared-IRAS diagram it is located in the oxygen-rich object region and (ⅲ)particularly, it has detected SiO maser emission.

The role of drug utilization evaluation in medical sciences

Background:Drug utilization evaluation(DUE)is defined by the World Health Organization(WHO)and focuses on the medical,social,and economic consequences of pharmaceutical marketing,distribution,prescribing,and usage in society.The WHO recommends a physician to every 1000 people.According to the recent data from the Health Ministry in 2019,in which 1.16 million doctors are of active population with just 80%,or 0.9 million,practicing.As a result,a ratio of 0.68 doctors for every 1000 people,which is much below as per the WHO reports.This article describes history,types,WHO guidelines,need and purpose of DUE.Objective:The main aim of this paper is to provide information about the rational use of medication in outpa­tient and inpatient department with special emphasis of DUEs.It also provides awareness directly to healthcare professionals,researchers,academicians,pharmacist and nurses to reduce the irrationality of medicines.Methods:The method used to compile this review information gathered from websites,Google scholar,PubMed,Research gate,and studies published on DUE from July 20 to Oct 22 were included as source of information.Results:We studied more than 35 published study on DUE,that reveals most of the physicians prescribed branded drugs not generic drugs,but WHO prescribing indicator allows to prescribe generic drugs in the hospital pharmacy to maintain better inventory control.It may also help to prevent pharmacist misunderstanding during dispensing.Conclusion:The use of generic prescription names avoids the possibility of medication product duplication and lowers patient costs.It is important to remember that incorrect medication prescriptions have impact on both patients and their family members.WHO indicators identify irrational prescribing behaviours to make therapy more rational and cost-effective.

基于药品分类的活性药物成分职业健康风险识别探索

目的 基于药品分类视角,分析药品分类编码所体现的疾病领域和作用机制信息,探索基于药品分类系统实现活性药物成分职业健康风险初步识别的可行性。方法 梳理《中华人民共和国药典(二部)》作为候选药品清单,应用解剖学、治疗学、化学(ATC)分类系统对美国国家职业安全卫生研究所(NIOSH)危害药品清单和候选药品清单进行编码,分析危害药品的疾病领域和作用机制。结果 NIOSH危害药品清单以L类抗肿瘤药和免疫功能调节药为主(占65%),覆盖我国药典候选药品中L类药品的93%,涉及9种作用机制。非L类药品分布较分散,以G类生殖泌尿系统和性激素、N类神经系统、C类心血管系统、J类系统用抗感染药、H类非性激素和胰岛素类的激素类系统用药为主。结论 基于疾病领域和作用机制识别高风险药品是对常规职业健康风险评估思路的拓展,是一种易于在作业场所实施的分类管理思路。在开展活性药物成分职业健康风险管控时,建议重点关注抗肿瘤药和免疫功能调节药。