Techniques for the dynamic randomization of network attributes

Critical infrastructure control systems continue to foster predictable communication paths and static configurations that allow easy access to our networked critical infrastructure around the world. This makes them attractive and easy targets for cyber-attack. We have developed technologies that address these attack vectors by automatically reconfiguring network settings. Applying these protective measures will convert control systems into «moving targets» that proactively defend themselves against attack. This «Moving Target Defense» (MTD) revolves about the movement of network reconfiguration, securely communicating reconfiguration specifications to other network nodes as required, and ensuring that connectivity between nodes is uninterrupted. Software-defined Networking (SDN) is leveraged to meet many of these goals. Our MTD approach eliminates adversaries targeting known static attributes of network devices and systems, and consists of the following three techniques: (1) Network Randomization for TCP/UDP Ports; (2) Network Randomization for IP Addresses; (3) Network Randomization for Network Paths In this paper, we describe the implementation of the aforementioned technologies. We also discuss the individual and collective successes for the techniques, challenges for deployment, constraints and assumptions, and the performance implications for each technique

The effect of premedication on oxygen saturation during the post-premedication period in 20 Chinese children undergoing elective surgery

Peri-operative continuous pulse oximetric data were studied in healthy Chinese children randomly allocated to receive either pethidine 1 mg kg-1 and atropine 0.02 mg kg-1 intramuscularly 90 min prior to surgery (n=10), or midazolam 0.5 mg kg-1 and atropine 0.02 mg kg-1 orally, 120 min before surgery (n=10). Data were collected during the night before surgery, after premedication and for 8h post-operatively. The pulse oximeter (Nellcor N-200E) output was retrospectively evaluated using Satmaster(®), a computer programme which permits storage, retrieval, signal evaluation and compilation of oximetric data. There was no significant difference in the frequency, duration, or magnitude of desaturation episodes recorded during the post-premedication period compared to the desaturation episodes which occurred in the same child during normal sleep, on the night before surgery. Furthermore, there was no significant difference in the desaturation data between the two premedicant regimens. No child recorded a genuine desaturation less than 80% for longer than 15s at any time during the study. Neither regimen significantly depressed saturation in otherwise healthy children presenting for minor surgical procedures.published_or_final_versio

Femtosecond laser inscription of depressed cladding single-mode mid-infrared waveguides in sapphire

Mid-infrared optical waveguides were inscribed in sapphire with femtosecond pulses at 515 nm. We show that such pulses induce a smooth negative refractive index change allowing for the inscription of a depressed cladding waveguide by closely overlapping the corresponding type I modification traces. The resulting structure consists of a highly symmetrical, uniform, and homogeneous waveguide. The size and numerical aperture of the waveguides were tailored to achieve efficient transmission in the mid-infrared. Single mode operation at a wavelength of 2850 nm and propagation loss of <0.37  dB/cm are reported for a 33 mm long depressed cladding waveguide. Thermal annealing was performed, and the refractive index contrast was still preserved to 50% (i.e., Δ=∼2.5×10−3) up to 1400°C

Enhancing search efficiency by means of a search filter for finding all studies on animal experimentation in PubMed

Collecting and analysing all available literature before starting an animal experiment is important and it is indispensable when writing a systematic review (SR) of animal research. Writing such review prevents unnecessary duplication of animal studies and thus unnecessary animal use (Reduction). One of the factors currently impeding the production of ‘high-quality’ SRs in laboratory animal science is the fact that searching for all available literature concerning animal experimentation is rather difficult. In order to diminish these difficulties, we developed a search filter for PubMed to detect all publications concerning animal studies. This filter was compared with the method most frequently used, the PubMed Limit: Animals, and validated further by performing two PubMed topic searches. Our filter performs much better than the PubMed limit: it retrieves, on average, 7% more records. Other important advantages of our filter are that it also finds the most recent records and that it is easy to use. All in all, by using our search filter in PubMed, all available literature concerning animal studies on a specific topic can easily be found and assessed, which will help in increasing the scientific quality and thereby the ethical validity of animal experiments

THE ROLE OF ARTIFICIAL INTELLIGENCE (AI) ON MRI BRAIN EXAMINATION WITH CLINICAL ISCHEMIC STROKE

Background: Application of Artificial Intelligence (AI) in radiology is named automatic image interpretation of neuroimaging stroke. It takes a short time to minimize the patient's brain damage. Purpose: Determine the role of AI in ischemic brain stroke MRI examination and find out the advantages and disadvantages of applying AI to ischemic brain stroke MRI examination. Review: It was a descriptive and qualitative study with a literature review approach. The selection of articles used the ScienceDirect, Scopus, ProQuest, PubMed, and Publish or Perish databases. The inclusion criteria included full articles, with the topic of AI on ischemic brain stroke MRI examinations published in the 2017 – 2022 range, articles published by English-language international journals with a classification of Q1 – Q3, and having DOI. Seven relevant pieces of article were obtained, then descriptive analysis was carried out by comparing and presenting the articles descriptively in tabular form. Result: The role of AI in MRI brain examination with clinical ischemic stroke, namely its role in automatic lesion segmentation, Time Since Stroke (TSS) classification, and infarct volume prediction. The advantages of AI included short image processing times and accurate results. The disadvantages of AI tended to decrease performance in small lesions, a large number of patients, limited data, and false positive results. The value of the Dice Score Coefficient (DSC) (0.53 – 0.86) was already high even though it had not reached 1 because it depended on the strength of the data used. Conclusion: The role of AI in MRI imaging of ischemic brain stroke helps in the diagnosis and prognosis of ischemic stroke patients. AI in stroke neuroimaging has advantages in time effectiveness and disadvantages in data limitations

Basal ganglia hyperdensity on computerised tomography of brain : a rare finding of non-ketotic hyperglycemia

Hyperdensity of basal ganglia in computed tomography (CT) of brain is alwaysrecognised as hemorrhagic stroke or calcification. Features of hyperglycemia include muscle weakness, hypotonia, pyramidal tract signs and hemichorea-hemiballismus (HC-HB), which mimic the symptoms of stroke. Hyperdensity of the basal ganglia was reported in patient with non-ketotic hyperglycemia (NKH). Inability to recognize the hyperdensity in CT brain as a feature of NKH may lead to failure of treatment. Early recognition and reversal of hyperglycemia will improve the outcome. This was a case of an atypical presentation of stroke-like symptoms with the neuroimaging finding showing asymmetric hyperdensity of basal ganglia. Neurological examination failed to elicit any sign of HC-HB. Laboratory test showed hyperglycemia with absence of acidosis and ketonaemia. The patient was diagnosed having basal ganglia hemorrhage and referred to the Neurosurgical team. However, the stroke-like symptoms completely resolved following the normalization of glucose level. This is the only other reported case of NKH with typical neuroimaging features not associated with HC-HB. One should be aware of the possibility of NKH in the absence of movement disorder with asymmetric basal ganglia hyperdensity in CT brain. Misinterpretation as acute intracranial bleeding may result in suboptimal management of the true underlying cause

Scientists and the 3Rs: attitudes to animal use in biomedical research and the effect of mandatory training in laboratory animal science

The 3Rs principle of replacement, reduction, and refinement has increasingly been endorsed by legislators and regulatory bodies as the best approach to tackle the ethical dilemma presented by animal experimentation in which the potential benefits for humans stand against the costs borne by the animals. Even when animal use is tightly regulated and supervised, the individual researcher’s responsibility is still decisive in the implementation of the 3Rs. Training in laboratory animal science (LAS) aims to raise researchers’ awareness and increase their knowledge, but its effect on scientists’ attitudes and practice has not so far been systematically assessed. Participants (n=206) in eight LAS courses (following the Federation of European Laboratory Animal Science Associations category C recommendations) in Portugal were surveyed in a self-administered questionnaire during the course. Questions were related mainly to the 3Rs and their application, attitudes to animal use and the ethical review of animal experiments. One year later, all the respondents were asked to answer a similar questionnaire (57% response rate) with added self-evaluation questions on the impact of training. Our results suggest that the course is effective in promoting awareness and increasing knowledge of the 3Rs, particularly with regard to refinement. However, participation in the course did not change perceptions on the current and future needs for animal use in research

Methylation-associated SNPs in adipose tissue

A genetic influence on methylation levels has been reported and methylation quantitative trait loci (meQTLs) have been identified in various tissues. The contribution of genetic and epigenetic factors in the development of the metabolic syndrome (MetS) has also been noted. In order to pinpoint candidate genes for testing association of SNPs with MetS and its components, we aimed to evaluate the contribution of genetic variations to differentially methylated CpG sites in severely obese men discordant for MetS. Genome-wide differential methylation analysis was conducted in visceral adipose tissue (VAT) of 31 severely obese men discordant for MetS (16 with and 15 without MetS) and identified ~17,800 variable CpG sites. Genome-wide association study conducted to identify SNPs (meQTL) associated with methylation levels at variable CpG sites revealed 2292 significant associations (P<2.22x10-11) involving 2182 unique meQTL regulating methylation levels of 174 variable CpG sites. Two meQTLs disrupting CpG sites located within the collagen encoding COL11A2 gene were tested for associations with MetS and its components in a cohort of 3021 obese individuals. Rare allele of these meQTLs showed association with plasma fasting glucose levels. Further analysis conducted on these meQTL suggested a biological impact mediated through disruption of transcription factor (TF) binding sites based on prediction of TF binding affinities. The current study identified meQTL in VAT of severely obese men and revealed associations of two COL11A2 meQTL with fasting glucose levels