Multiple sclerosis(MS) is a chronic inflammatory condition of the central nervous system determined by a presumed autoimmune process mainly directed against myelin components but also involving axons and neurons. Acut...Multiple sclerosis(MS) is a chronic inflammatory condition of the central nervous system determined by a presumed autoimmune process mainly directed against myelin components but also involving axons and neurons. Acute demyelination shows as clinical relapses that may fully or partially resolve, while chronic demyelination and neuroaxonal injury lead to persistent and irreversible neurological symptoms, often progressing over time. Currently approved disease-modifying therapies are immunomodulatory or immunosuppressive drugs that significantly although variably reduce the frequency of attacks of the relapsing forms of the disease. However, they have limited efficacy in preventing the transition to the progressive phase of MS and are of no benefit after it has started. It is therefore likely that the potential advantage of a given treatment is condensed in a relatively limited window of opportunity for each patient, depending on individual characteristics and disease stage, most frequently but not necessarily in the early phase of the disease. In addition, a sizable proportion of patients with MS may have a very mild clinical course not requiring a disease-modifying therapy. Finally, individual response to existing therapies for MS varies significantly across subjects and the risk of serious adverse events remains an issue, particularly for the newest agents. The present review is aimed at critically describing current treatment strategies for MS with a particular focus on the decision of starting, switching and stopping commercially available immunomodulatory and immunosuppressive therapies.展开更多
面向水电站场景,为解决传统黑启动方案响应慢、可靠性差以及经济性低等问题,将超级电容器(super capacitor,SC)与不间断电源(uninterruptible power supply,UPS)结合,构建一种基于SC的混合储能系统(hybrid energy storage system,HESS)...面向水电站场景,为解决传统黑启动方案响应慢、可靠性差以及经济性低等问题,将超级电容器(super capacitor,SC)与不间断电源(uninterruptible power supply,UPS)结合,构建一种基于SC的混合储能系统(hybrid energy storage system,HESS)黑启动装置.基于主从控制,提出了一种黑启动自适应柔性切换控制策略.作为主控单元,UPS采用电压/频率(voltage/frequency,V/F)控制持续提供电能支撑;作为从控单元,SC在黑启动阶段利用恒功率控制与虚拟同步发电机(virtual synchronous generator,VSG)技术提供大电流支撑.为保证HESS切换过程中稳定运行,采用一种改进预同步控制对相位和幅值进行预同步,实现HESS柔性平滑切换,同时提出一种可控硅整流器(silicon controlled rectifier,SCR)强制关断策略,实现HESS快速黑启动切换响应.仿真结果表明所提方法能够实现HESS黑启动平滑切换控制,实现毫秒级别快速响应,提高了水电站黑启动稳定性与经济性.展开更多
文摘Multiple sclerosis(MS) is a chronic inflammatory condition of the central nervous system determined by a presumed autoimmune process mainly directed against myelin components but also involving axons and neurons. Acute demyelination shows as clinical relapses that may fully or partially resolve, while chronic demyelination and neuroaxonal injury lead to persistent and irreversible neurological symptoms, often progressing over time. Currently approved disease-modifying therapies are immunomodulatory or immunosuppressive drugs that significantly although variably reduce the frequency of attacks of the relapsing forms of the disease. However, they have limited efficacy in preventing the transition to the progressive phase of MS and are of no benefit after it has started. It is therefore likely that the potential advantage of a given treatment is condensed in a relatively limited window of opportunity for each patient, depending on individual characteristics and disease stage, most frequently but not necessarily in the early phase of the disease. In addition, a sizable proportion of patients with MS may have a very mild clinical course not requiring a disease-modifying therapy. Finally, individual response to existing therapies for MS varies significantly across subjects and the risk of serious adverse events remains an issue, particularly for the newest agents. The present review is aimed at critically describing current treatment strategies for MS with a particular focus on the decision of starting, switching and stopping commercially available immunomodulatory and immunosuppressive therapies.
