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1.
Sensors (Basel) ; 20(21)2020 Oct 28.
Article in English | MEDLINE | ID: mdl-33126629

ABSTRACT

Internet of Things (IoT) technology is increasingly pervasive in all aspects of our life and its usage is anticipated to significantly increase in future Smart Cities to support their myriad of revolutionary applications. This paper introduces a new architecture that can support several IoT-enabled smart home use cases, with a specified level of security and privacy preservation. The security threats that may target such an architecture are highlighted along with the cryptographic algorithms that can prevent them. An experimental study is performed to provide more insights about the suitability of several lightweight cryptographic algorithms for use in securing the constrained IoT devices used in the proposed architecture. The obtained results showed that many modern lightweight symmetric cryptography algorithms, as CLEFIA and TRIVIUM, are optimized for hardware implementations and can consume up to 10 times more energy than the legacy techniques when they are implemented in software. Moreover, the experiments results highlight that CLEFIA significantly outperforms TRIVIUM under all of the investigated test cases, and the latter performs 100 times worse than the legacy cryptographic algorithms tested.

2.
Foot Ankle Int ; 37(2): 218-26, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26424725

ABSTRACT

BACKGROUND: We present a new method to stabilize proximal crescentic osteotomies (PCOs) for the correction of moderate to severe hallux valgus. METHODS: A single-center prospective study with a consecutive series of 72 patients (94 feet) with a PCO was performed using a head locking X-plate. The primary aim was to investigate the stability of the osteotomy, measuring the dorsal elevation of the first metatarsal head, first cuneiform height, talus-first metatarsal angle, and first metatarsal inclination pre- and postoperatively. A secondary outcome assessed weight distribution during gait, quality of life, and radiologically documented bone healing process. RESULTS: Ninety-three percent of the feet were within ±2 mm change for dorsal elevation of the first metatarsal head, and 72% for the medial cuneiform height. Eighty-nine percent were within ±4 degrees change for the first metatarsal inclination, 73% for the talus-first metatarsal angle, and 100% for the calcaneus pitch angle. The mean changes between pre- and 1-year postoperative were not significantly different for any of the stability measurements except for the first metatarsal inclination angle. The SF36 showed a significant improvement of physical function, general health, and decreased bodily pain. Harris mat footprints showed a decrease of 46% underneath the second and a pressure decrease of 40% underneath the third metatarsal head. CONCLUSION: This technique, of using a head locking X-plate to stabilize the PCO, showed satisfactory and reproducible results in terms of stability, clinical outcome, bone healing, and patient satisfaction. The plate provided substantial support for the PCO resulting in adequate and easy fixation. LEVEL OF EVIDENCE: Level IV, retrospective case series.


Subject(s)
Bone Plates , Hallux Valgus/surgery , Metatarsal Bones/surgery , Osteotomy/instrumentation , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Patient Outcome Assessment , Patient Satisfaction , Pressure , Prospective Studies , Severity of Illness Index , Young Adult
3.
J Sci Med Sport ; 14(6): 529-34, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21602102

ABSTRACT

To assess the effects of currently used prescribed in-shoe custom foot orthoses (CFOs) on a number of biomechanical variables during the power phase of cycling, including: hip adduction, knee abduction and tibial internal rotation. Before and after cross-over study recording subjects' biomechanical variables with and without their CFOs. Twelve competitive cyclists, currently using prescribed in-shoe CFOs, performed two exercise bouts on a stationary trainer, with 3-dimensional data recorded on an 8 camera Vicon Mx system. 2-way ANOVA statistical analysis of Null vs Orthotic condition, and left leg vs right leg. No systematic effects from the CFOs were seen. A trend towards reduced tibial internal rotation range of movement was found (P<0.072). Significant subject-specific effects from the CFOs were seen (P<0.05). Three distinct patterns of knee movement were observed. All subjects had significant left to right leg differences. CFOs do not produce systematic effects on cycling biomechanics. Significant subject-specific biomechanical effects can be produced by CFOs utilizing rearfoot and/or forefoot wedges. An individualised approach to orthotic prescription, and attention to the forefoot-rearfoot relationship, is recommended.


Subject(s)
Athletic Performance/physiology , Bicycling , Orthotic Devices , Adult , Athletes , Biomechanical Phenomena , Cross-Over Studies , Female , Hip/physiology , Humans , Leg/physiology , Male , Middle Aged , Rotation , Tibia/physiology
4.
Virtual Mentor ; 13(4): 241-7, 2011 Apr 01.
Article in English | MEDLINE | ID: mdl-23131332
5.
Int J Epidemiol ; 39(5): 1345-59, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20439481

ABSTRACT

BACKGROUND: Meta-analysis of individual participant time-to-event data from multiple prospective epidemiological studies enables detailed investigation of exposure-risk relationships, but involves a number of analytical challenges. METHODS: This article describes statistical approaches adopted in the Emerging Risk Factors Collaboration, in which primary data from more than 1 million participants in more than 100 prospective studies have been collated to enable detailed analyses of various risk markers in relation to incident cardiovascular disease outcomes. RESULTS: Analyses have been principally based on Cox proportional hazards regression models stratified by sex, undertaken in each study separately. Estimates of exposure-risk relationships, initially unadjusted and then adjusted for several confounders, have been combined over studies using meta-analysis. Methods for assessing the shape of exposure-risk associations and the proportional hazards assumption have been developed. Estimates of interactions have also been combined using meta-analysis, keeping separate within- and between-study information. Regression dilution bias caused by measurement error and within-person variation in exposures and confounders has been addressed through the analysis of repeat measurements to estimate corrected regression coefficients. These methods are exemplified by analysis of plasma fibrinogen and risk of coronary heart disease, and Stata code is made available. CONCLUSION: Increasing numbers of meta-analyses of individual participant data from observational data are being conducted to enhance the statistical power and detail of epidemiological studies. The statistical methods developed here can be used to address the needs of such analyses.


Subject(s)
Coronary Disease/blood , Coronary Disease/epidemiology , Data Interpretation, Statistical , Epidemiologic Methods , Fibrinogen/analysis , Age Factors , Humans , Proportional Hazards Models , Risk Factors , Sex Factors , Smoking/epidemiology , Time Factors
6.
JAMA ; 302(18): 1993-2000, 2009 Nov 11.
Article in English | MEDLINE | ID: mdl-19903920

ABSTRACT

CONTEXT: Associations of major lipids and apolipoproteins with the risk of vascular disease have not been reliably quantified. OBJECTIVE: To assess major lipids and apolipoproteins in vascular risk. DESIGN, SETTING, AND PARTICIPANTS: Individual records were supplied on 302,430 people without initial vascular disease from 68 long-term prospective studies, mostly in Europe and North America. During 2.79 million person-years of follow-up, there were 8857 nonfatal myocardial infarctions, 3928 coronary heart disease [CHD] deaths, 2534 ischemic strokes, 513 hemorrhagic strokes, and 2536 unclassified strokes. MAIN OUTCOME MEASURES: Hazard ratios (HRs), adjusted for several conventional factors, were calculated for 1-SD higher values: 0.52 log(e) triglyceride, 15 mg/dL high-density lipoprotein cholesterol (HDL-C), 43 mg/dL non-HDL-C, 29 mg/dL apolipoprotein AI, 29 mg/dL apolipoprotein B, and 33 mg/dL directly measured low-density lipoprotein cholesterol (LDL-C). Within-study regression analyses were adjusted for within-person variation and combined using meta-analysis. RESULTS: The rates of CHD per 1000 person-years in the bottom and top thirds of baseline lipid distributions, respectively, were 2.6 and 6.2 with triglyceride, 6.4 and 2.4 with HDL-C, and 2.3 and 6.7 with non-HDL-C. Adjusted HRs for CHD were 0.99 (95% CI, 0.94-1.05) with triglyceride, 0.78 (95% CI, 0.74-0.82) with HDL-C, and 1.50 (95% CI, 1.39-1.61) with non-HDL-C. Hazard ratios were at least as strong in participants who did not fast as in those who did. The HR for CHD was 0.35 (95% CI, 0.30-0.42) with a combination of 80 mg/dL lower non-HDL-C and 15 mg/dL higher HDL-C. For the subset with apolipoproteins or directly measured LDL-C, HRs were 1.50 (95% CI, 1.38-1.62) with the ratio non-HDL-C/HDL-C, 1.49 (95% CI, 1.39-1.60) with the ratio apo B/apo AI, 1.42 (95% CI, 1.06-1.91) with non-HDL-C, and 1.38 (95% CI, 1.09-1.73) with directly measured LDL-C. Hazard ratios for ischemic stroke were 1.02 (95% CI, 0.94-1.11) with triglyceride, 0.93 (95% CI, 0.84-1.02) with HDL-C, and 1.12 (95% CI, 1.04-1.20) with non-HDL-C. CONCLUSION: Lipid assessment in vascular disease can be simplified by measurement of either total and HDL cholesterol levels or apolipoproteins without the need to fast and without regard to triglyceride.


Subject(s)
Lipids/blood , Vascular Diseases/blood , Apolipoproteins/blood , Cholesterol, HDL/blood , Coronary Disease/blood , Coronary Disease/epidemiology , Female , Humans , Male , Middle Aged , Proportional Hazards Models , Regression Analysis , Risk Factors , Stroke/blood , Stroke/epidemiology , Triglycerides/blood , Vascular Diseases/epidemiology
7.
Opt Express ; 17(15): 12668-77, 2009 Jul 20.
Article in English | MEDLINE | ID: mdl-19654671

ABSTRACT

Return-to-Zero (RZ) and Non-Return-to-Zero (NRZ) Differential Phase Shift Keyed (DPSK) systems require cheap and optimal transmitters for widespread implementation. The authors report on a gain switched Discrete Mode (DM) laser that can be employed as a cost efficient transmitter in a 10.7 Gb/s RZ DPSK system and compare its performance to that of a gain switched Distributed Feed-Back (DFB) laser. Experimental results show that the gain switched DM laser readily provides error free performance and a receiver sensitivity of -33.1 dBm in the 10.7 Gbit/s RZ DPSK system. The standard DFB laser on the other hand displays an error floor at 10(-1) in the same RZ DPSK system. The difference in performance, between the two types of gain switched transmitters, is analysed by investigating their linewidths. We also demonstrate, for the first time, the generation of a highly coherent gain switched pulse train which displays a spectral comb of approximately 13 sidebands spaced by the 10.7 GHz modulation frequency. The filtered side-bands are then employed as narrow linewidth Continuous Wave (CW) sources in a 10.7 Gb/s NRZ DPSK system.

8.
JAMA ; 302(4): 412-23, 2009 Jul 22.
Article in English | MEDLINE | ID: mdl-19622820

ABSTRACT

CONTEXT: Circulating concentration of lipoprotein(a) (Lp[a]), a large glycoprotein attached to a low-density lipoprotein-like particle, may be associated with risk of coronary heart disease (CHD) and stroke. OBJECTIVE: To assess the relationship of Lp(a) concentration with risk of major vascular and nonvascular outcomes. STUDY SELECTION: Long-term prospective studies that recorded Lp(a) concentration and subsequent major vascular morbidity and/or cause-specific mortality published between January 1970 and March 2009 were identified through electronic searches of MEDLINE and other databases, manual searches of reference lists, and discussion with collaborators. DATA EXTRACTION: Individual records were provided for each of 126,634 participants in 36 prospective studies. During 1.3 million person-years of follow-up, 22,076 first-ever fatal or nonfatal vascular disease outcomes or nonvascular deaths were recorded, including 9336 CHD outcomes, 1903 ischemic strokes, 338 hemorrhagic strokes, 751 unclassified strokes, 1091 other vascular deaths, 8114 nonvascular deaths, and 242 deaths of unknown cause. Within-study regression analyses were adjusted for within-person variation and combined using meta-analysis. Analyses excluded participants with known preexisting CHD or stroke at baseline. DATA SYNTHESIS: Lipoprotein(a) concentration was weakly correlated with several conventional vascular risk factors and it was highly consistent within individuals over several years. Associations of Lp(a) with CHD risk were broadly continuous in shape. In the 24 cohort studies, the rates of CHD in the top and bottom thirds of baseline Lp(a) distributions, respectively, were 5.6 (95% confidence interval [CI], 5.4-5.9) per 1000 person-years and 4.4 (95% CI, 4.2-4.6) per 1000 person-years. The risk ratio for CHD, adjusted for age and sex only, was 1.16 (95% CI, 1.11-1.22) per 3.5-fold higher usual Lp(a) concentration (ie, per 1 SD), and it was 1.13 (95% CI, 1.09-1.18) following further adjustment for lipids and other conventional risk factors. The corresponding adjusted risk ratios were 1.10 (95% CI, 1.02-1.18) for ischemic stroke, 1.01 (95% CI, 0.98-1.05) for the aggregate of nonvascular mortality, 1.00 (95% CI, 0.97-1.04) for cancer deaths, and 1.00 (95% CI, 0.95-1.06) for nonvascular deaths other than cancer. CONCLUSION: Under a wide range of circumstances, there are continuous, independent, and modest associations of Lp(a) concentration with risk of CHD and stroke that appear exclusive to vascular outcomes.


Subject(s)
Coronary Disease/blood , Coronary Disease/epidemiology , Lipoprotein(a)/blood , Stroke/blood , Stroke/epidemiology , Cause of Death , Humans , Risk Factors
9.
Virtual Mentor ; 10(8): 485-6, 2008 Aug 01.
Article in English | MEDLINE | ID: mdl-23211076
10.
Virtual Mentor ; 10(12): 781-3, 2008 Dec 01.
Article in English | MEDLINE | ID: mdl-23211942
11.
Virtual Mentor ; 8(6): 387-91, 2006 Jun 01.
Article in English | MEDLINE | ID: mdl-23234669
12.
Virtual Mentor ; 8(9): 602-8, 2006 Sep 01.
Article in English | MEDLINE | ID: mdl-23234713
13.
Virtual Mentor ; 8(12): 863-70, 2006 Dec 01.
Article in English | MEDLINE | ID: mdl-23241550
14.
Virtual Mentor ; 7(12)2005 Dec 01.
Article in English | MEDLINE | ID: mdl-23256974
15.
Virtual Mentor ; 6(4)2004 Apr 01.
Article in English | MEDLINE | ID: mdl-23260476
16.
Teratog Carcinog Mutagen ; Suppl 2: 31-41, 2003.
Article in English | MEDLINE | ID: mdl-14691978

ABSTRACT

Telomerase-targeted strategies have aroused recent interest in anti-cancer chemotherapy, because DNA-binding drugs can interact with high-order tetraplex rather than double-stranded (duplex) DNA targets in tumour cells. However, the protracted cell-drug exposure times necessary for clinical application require that telomerase inhibitory efficacy must be accompanied by both low inherent cytotoxicity and the absence of mutagenicity/genotoxicity. For the first time, the genotoxicity of a number of structurally diverse DNA-interactive telomerase inhibitors is examined in the Ames test using six Salmonella typhimurium bacterial strains (TA1535, TA1537, TA1538, TA98, TA100, and TA102). DNA damage induced by each agent was also assessed using the Comet assay with human lymphocytes. The two assay procedures revealed markedly different genotoxicity profiles that are likely to reflect differences in metabolism and/or DNA repair between bacterial and mammalian cells. The mutational spectrum for a biologically active fluorenone derivative, shown to be mutagenic in the TA100 strain, was characterised using a novel and rapid assay method based upon PCR amplification of a fragment of the hisG46 allele, followed by RFLP analysis. Preliminary analysis indicates that the majority (84%) of mutations induced by this compound are C --> A transversions at position 2 of the missense proline codon of the hisG46 allele. However, despite its genotoxic bacterial profile, this fluorenone agent gave a negative response in the Comet assay, and demonstrates how unwanted systemic effects (e.g., cytotoxicity and genotoxicity) can be prevented or ameliorated through suitable molecular fine-tuning of a candidate drug in targeted human tumour cells.


Subject(s)
Antineoplastic Agents/toxicity , DNA, Bacterial/drug effects , Enzyme Inhibitors/toxicity , Telomerase/antagonists & inhibitors , Comet Assay , DNA Damage , DNA Repair , DNA, Bacterial/metabolism , Fluorenes/toxicity , Humans , Lymphocytes/drug effects , Mutagenicity Tests , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Salmonella typhimurium/drug effects , Salmonella typhimurium/genetics , Telomerase/metabolism
18.
Virtual Mentor ; 5(7)2003 Jul 01.
Article in English | MEDLINE | ID: mdl-23267650
19.
Curr Pharm Des ; 8(27): 2491-504, 2002.
Article in English | MEDLINE | ID: mdl-12369943

ABSTRACT

Telomerase is a cellular ribonucleoprotein reverse transcriptase responsible for the maintenance of telomeres, the tandemly repeating guanine-rich nucleic acid sequences at the 3'-ends of eukaryotic chromosomes that serve to protect chromosomal stability and maintain integrity. Telomerase enzyme activity is essential for the sustained proliferation of most immortal cells, including cancer cells, and is currently an important recognised target for the development of novel and potentially tumour-specific anticancer chemotherapeutics. Herein, we review recent advances in the design and development of telomerase inhibitors for the treatment of cancer. To date, these have included antisense strategies, reverse transcriptase inhibitors, and agents capable of interacting with high-order telomeric DNA tetraplex (or "G-quadruplex") structures in such a way as to prevent enzyme access to its required linear telomeric DNA substrate. Critical appraisal of each distinct approach is provided together with highlighted areas for continued development necessary to further refine the present disparate classes of telomerase inhibitors for use in clinically viable therapies.


Subject(s)
Drug Design , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/therapeutic use , Neoplasms/drug therapy , Telomerase/antagonists & inhibitors , Animals , Enzyme Inhibitors/pharmacology , Humans , Neoplasms/enzymology , Telomerase/metabolism
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