Factors influencing the implementation of information systems security strategies in organisations

Many organizations still rely on deterrence to control insider threats and on purely preventive strategies to control outsider threats. Such a simple approach to organizational information security is no longer viable given the increasing operational sophistication of current security threat agents and the complexity of information technology infrastructure. Effective implementation of security requires organizations to select a combination of strategies that work in tandem and best suits their security situation. This paper addresses the identification and classification of factors that influence implementation of security strategies in organizations. In this paper, we develop a preliminary architecture that aims to assist organizations in deciding how strategies can be designed to complement each other to improve the cost-effectiveness of security.<br /

A hybrid method to improve target registration accuracy in surgical navigation

Background: The accuracy of surgical navigation depends greatly on that of registration between the patient and the medical image. Point-based registration has been the most common and reliable method, which typically uses skin markers. Unfortunately, high registration accuracy around the markers is not sustained at targets deeply seated within the body. To address such increase in target registration error (TRE), we proposed a hybrid point-based registration method that incorporates anatomical landmarks near the target. Material and methods: Ultrasound calibration is performed with an optical tracker for coordinate frame conversion of image coordinates into the real world. With the calibrated ultrasound probe, we could non-invasively obtain landmark positions near the target, being used together with skin markers for registration. Results: In the experiment, we examined registration accuracies achieved with and without use of an anatomical landmark. We confirmed that using an additional anatomical landmark in registration resulted in an increase in fiducial regsitration error (FRE), but a significant decrease in TRE (p &lt; 0.001). Conclusion: We proposed and demonstrated the effectiveness of a hybrid method that uses both artificial and anatomical landmarks for patient-to-image registration. The experimental results confirmed that an improvement in TRE was evident by the proposed method, suggesting its feasibility in various spinal surgeries. © 2015 © Informa Healthcare.

Cardiovascular and Autonomic Responses to Acute Exposure to Mild Hypercapnic Conditions in Middle-Aged Adults

Sedentary lifestyle in the US has significantly increased in recent decades, specifically, adults in modern workplaces have been known to be exposed to ~6 hours of uninterrupted prolonged sitting (PS) per day. PS has been shown to cause endothelial dysfunction, leading to an increased risk for cardiovascular disease such as peripheral arterial disease. Additionally, elevations in carbon dioxide (hypercapnia), commonly observed in workplaces such as offices, have been known to impair cardiovascular function. Interrupting PS with muscular contractions has been used to prevent the negative effects of PS. However, the underlying protective mechanism(s) of these muscular contractions during PS with hypercapnia in middle-aged adults is currently unknown. The purpose of this study was to examine the impacts of muscle contraction, specifically, activation of group III/IV muscle afferents via passive and active leg movement in middle-aged office workers during PS in a mild-hypercapnic environment. Healthy sedentary middle-aged adults (n=5, age: 45 ± 9) completed 3 visits in a mild-hypercapnic environment: control (CON) passive (PASS) and active (ACT) to determine how activating group III/IV muscle afferents during 2.5 hours of PS affect cardiovascular function. Following PS, popliteal shear rate increased in ACT (23.98%) compared to PASS (4.09%) and CON (11.44%). Popliteal artery flow-mediated dilation showed greater increase in ACT (3.33%) compared to PASS (1.44%) and CON (1.12%). This study provides novel insight towards the cardiovascular effects of PS with mild hypercapnia in sedentary middle-aged adults, and the roles of group III and IV muscle afferent activation in the preservation for vascular function

Integrative function of microcirculation and skeletal muscle function in peripheral artery disease

Peripheral artery disease (PAD) is an atherosclerotic disease that impairs lower-extremity circulatory function. Attenuated skeletal muscle mitochondrial function and oxygen utility capacity have been reported in the ischemic limbs; however, the underlying mechanisms are not well-understood. We investigated the impacts of chronic ischemia on skeletal muscle arteriole vasodilatory function and its contribution to skeletal muscle mitochondrial function and microvascular oxygen delivery and utilization capacity (TOI) in PAD. Skeletal muscle and arteriole samples from patients with PAD (n=18, 68.4±10.2 years) and age-matched controls (CON, n=11, 64.6±9.3 years) were harvested. Endothelial-dependent and endothelial-independent vasodilatory function was assessed by flow, acetylcholine (ACh), and sodium nitroprusside (SNP), and skeletal muscle mitochondrial function was measured by high-resolution respirometry. TOI was assessed by near-infrared spectroscopy in-vivo. Endothelial-dependent vasodilation was attenuated in PAD in response to ACh (10-3M, CON: 71.1±7%, PAD: 45.5±6%, PP-3M, CON: 101.5±4%, PAD: 91.6±5%, P=0.12). Complex I + II state 3 respiration was lower in PAD (CON: 26.1±2.1, PAD: 7.8±1.4 pmol∙s-1∙mg-1, P-1, Pr=0.6 and r=0.5, respectively, Pr=0.5 and r=0.6, respectively,

A preliminary study on surgical navigation for epiduroscopic laser neural decompression

Epiduroscopic laser neural decompression is an emerging therapeutic modality to treat lumbar spine pathologies including chronic low back pain, spinal stenosis, and disk herniation via catheter insertion followed by laser ablation of the lesion. Despite the efficacy of epiduroscopic laser neural decompression, excessive radiation doses due to fluoroscopy during epiduroscopic laser neural decompression have limited its widespread application. To address the issue, we propose a surgical navigation system to assist in epiduroscopic laser neural decompression procedures using radiation-free image guidance. An electromagnetic tracking system was used as the basic modality to track the internal location of the surgical instrument with respect to the patient body. Patient-to-image registration was carried out using the point-based registration method to determine the transformation between the coordinate system of the patient and that of the medical images. We applied the proposed system in epiduroscopic laser neural decompression procedures to assess its effectiveness, and the outcomes confirmed its clinical feasibility. To the best of our knowledge, this is a report on the first surgical navigation applied for epiduroscopic laser neural decompression procedure. © IMechE 2015.