System vulnerabilities

At least two specific properties make the immune system vulnerable to chemical or physical insults (1) the immune system develops rather late in life (thymus development lasts at least until puberty), and some bone marrow-dependent immune components are continuously renewed (i.e., granulocytes), and (2) each pathogen attack, as well as immune surveillance, demands a delicate control of the balance between activation, silencing, and regulation of immune reactivity. 

It should also be emphasized that this adaptation of the Kalecki system represents an interpretation of the reproduction schema that is consistent with Marx s system. As Lee (1998) has argued, Kalecki has a restrictive production model in which each department is vertically integrated, producing its own raw materials. In contrast, Marx assumes that raw materials are a part of constant capital, produced in the first department and circulated to other departments. A failure to fully take into account connections between industries leaves the Kalecki system vulnerable to a SrafFian critique. Steedman (1992), for example, has lambasted the Kaleckian price system for the absence of multisectoral relationships. By establishing the Kalecki principle in an input-output context, an interpretation of the reproduction schema is possible in which linkages between industries are taken seriously. 

In addition to the control system vulnerabilities mentioned earlier, several factors have contributed to the escalation of risk to control systems, including (1) the adoption of standardized technologies with known vulnerabilities, (2) the connectivity of control systems to other networks, (3) constraints on the implementation of existing security technologies and practices, (4) insecure remote connections, and (5) the widespread availability of technical information about control systems. 

The objective of the security policy is to either minimize the likelihood of impact occurrence or to at least minimize the consequences that an undesirable event may have. The former can be done either by reducing the system vulnerabilities or by decreasing the likelihood that a threat will successfully exploit some vulnerability. Clearly threats cannot be controlled, being outside the system control domain. In order to achieve these goals, appropriate countermeasures should be put in place. 

In addition, it should be considered that the picture is further complicated by the fact that security solutions require the application of additional socio-technical systems, vulnerable themselves, and which can be used themselves as attack means (cf. attack to the Twin Towers on September 11th, 2001). 

Virus protection activities defined in a policy and procedure for governing vims protection for SCADA systems include methods for checking automation system data and software integrity, e.g., standards and requirements for installing fixes/patches for known automation control system problems. Periodic assessment of automation control system vulnerabilities are to be undertaken in the light of emerging knowledge. 

Research is going on to improve the DELFIA system , because of drawbacks such as the time-consuming conversion of the non-fluorescent RE label into a luminescent complex, or the system vulnerability to contamination by RE due to the excess of the reagents ntfa and topo. An alternative is the use of a -diketone that can be covalently bonded to proteins such as 5-(4,4,4-trifluoro-l,3-dioxobutyl)-2-thiophenesulfonyl chloride (ctta) . Since the stability of the RE + complexes formed by this ligand is quite low, a large excess of RE + has to be used to shift the equilibrium to the rare-earth complex. More stable europium complexes can be obtained by the use of tetradentate fi-diketonates, such as 7a-7d, anchored on a functionalized o-terphenyl skeleton, or 8a-8c, anchored on a biperfluorobutadiene skeleton . ... 

In addition to the main document, a number of additional guidance documents have been published during recent years. These include an article in Pharmaceutical Engineeringf about a risk-based approach to computer validation. The article starts from the risk assessment given in GAMP 4 and provides a model for a system risk assessment based on the risk level of the business process supported by the system and the system vulnerability. As an outcome of this assessment, it summarizes which validation activities are appropriate for which risk level. 

Information technology has made anything that requires the understanding of large and complex systems vulnerable to exploration as never before. ... 

Chemicals generally perturb neurological function of the adult by interfering differentially with the structure and function of specific neural pathways, circuits, and systems. Vulnerable circuits within the brain include those that modulate and affect efferent output. Most commonly affected, however, are the peripheral neurons in pathways that relay information to and from the brain. 

Anonymous Janes Defence Weekly, 13 August, 1997. Ventilation Systems Vulnerable to Bioterrorism, p. 14. 

This might seem like a duplication of effort, but does not have to be. Each tool/technique approaches system vulnerabilities from its own perspective and may all reference the same quaUtative/quantitative analysis which evidences its mitigation and or probability deceleration. 

ID Component in zone External failure mode(s) Intrinsic hazards Systemic vulnerabilities Effect on the aircraft Corrective/preventative action and/or mitigations... 

A task still in the making is to develop metrics and indicators for risks which may contribute to making the overall supply system vulnerable. These may then be used in the life-cycle perspective, observing time-evolvement of risk factors. 

Irrespective of the exact numbers, whether 50,000 or 100,000 deaths per year, preventable medical injury is a serious problem. For health care leaders, the message is clear allowing system vulnerabilities to cause harm to patients is unacceptable. Academicians may continue to debate methodology, but the leader s job is to focus on the design and implementation of stife care delivery systems. 

Identified system vulnerabilities are useful as initial data sources to prevent failure from reaching a patient. 

The systems framework does identify individual human action or inaction as part of a complex system but places greater emphasis on systemic vulnerabilities. These include the design, construction, and maintenance of work processes allocation of resources technology expectations training and development of operational procedures (Leape, 1994). 

Among the significant contributions from human factors research to the field of patient safety is the notion that fallibility is part of the human condition. Therefore creating safety requires changing the conditions in which human beings work. Although individual failures and system vulnerabilities are inevitable, adverse events and harm resulting from them need not be. 

Designing fail-safe care delivery processes that deflect system errors and system vulnerabilities before they reach a patient to create harm... 

The implementation of a voluntary blameless reporting system is a deep cultural intervention in an organization that legitimizes transparency of system vulnerability, nurtures an alert field, and empowers front-line providers to expose risks. In turn, the front line learns to expect responses from managers at the blunt end to support the work of improvement. The few organizations in health care that have developed reporting systems believe that the effort is 75 percent social and only 25 percent technical (personal communication from Anne-Claire France, former director of the Center for Healthcare Improvement, Memorial Hermann Healthcare... 

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