Detection of DNS Traffic Anomalies in Large Networks

Almost every Internet communication is preceded by a translation of a DNS name to an IP address. Therefore monitoring of DNS traffic can effectively extend capabilities of current methods for network traffic anomaly detection. In order to effectively monitor this traffic, we propose a new flow metering algorithm that saves resources of a flow exporter. Next, to show benefits of the DNS traffic monitoring for anomaly detection, we introduce novel detection methods using DNS extended flows. The evaluation of these methods shows that our approach not only reveals DNS anomalies but also scales well in a campus network.Téměř každá síťová komunikace je předcházena překladem doménového jména na IP adresu. Měření a následná analýza DNS provozu může účinně rozšířit schopnosti současných metod pro detekci anomálií v celkovém síťovém provozu. Aby bylo možné tento provoz efektivně sledovat, navrhujeme v článku nový algoritmus pro sběr a export síťových toků šetřicí zdroje exportéru. Dále, abychom ukázali výhody monitorování DNS provozu pro detekci anomálií, představujeme nové detekční metody využívající síťové toky rozšířené o informace z DNS paketů. Z vyhodnocení těchto metod vyplývá, že navržený přístup umožňuje úspěšně detekovat anomálie v DNS provozu a to dokonce i v rozsáhlých, univerzitních sítích

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

Relationships between water temperature, nutrients and dissolved oxygen in the Northern Gulf of Aqaba, Red Sea

Five years (1998, 2000–2003) of summer records of temperature, nutrients and dissolved oxygen concentrations in the upper 400 m of the water column of the northern Gulf of Aqaba were employed to produce a simple statistical model of the relationship between temperature versus nitrate, phosphate, silicate andd issolved oxygen concentrations. Temperature profiles in the upper 400 m during summer revealeda clear thermocline in the upper 200 m. This was reflected in nutrient ando xygen concentrations as nitrate, phosphate, and silicate increasedfr om the surface to deep water while dissolved oxygen decreased. The best fit relationship between temperature versus nitrate andphosphate was inverse linear and the best fit correlation between temperature versus silicate andd issolvedo xygen was fractional. The observedn utrient concentrations were shaped by a combination of the hydrodynamics and biological factors. Deep winter mixing and high nutrient concentrations dominate during winter. Shortly after the water stratifies in spring, the nutrients are drawn down by phytoplankton during the spring bloom and remain low throughout the rest of the year. The regression equations presented here will be useful in estimating nutrient concentrations from temperature records as long as the annual natural cycle is the main driver of nutrient concentrations and external inputs are insignificant. Deviations from these relationships in the future could provide insight into modifications in the nutrient concentrations probably resulting from new nutrient sources, such as anthropogenic inputs

Circulation and winter deep-water formation in the Northern Red Sea

Water mass characteristics and circulation patterns in the Gulf of Aqaba and northern Red Sea were studied for the first time during the r/v ‘Meteor’ cruise leg 44/2 from February 21st to March 7th 1999 using temperature-salinity profiles and current observations. The deep water in the northern Red Sea had similar characteristics to the well-mixed upper 450 m of water in the Gulf of Aqaba. This indicates that the winter mixed waters of the Gulf of Aqaba contribute significantly to deep-water in the northern Red Sea. Mixing in the Gulf of Aqaba is an annually repeated event that starts with the cooling of the surface water during November–December and reaches a maximum, which in most years extends down the entire water column in March–April. Waters deeper than the mixed layer in the Gulf seems to be rather passive and play no specific role in water mass formation in the northern Red Sea. In contrast to the Gulf of Aqaba, the upper 200 m of the northern Red Sea were stratified (21.5–23.5◦C, and 40.0–40.3 PSU). Stratification at the Strait of Tiran was weak (21.6–22.0◦C, and 40.3–40.5 PSU) and disappeared abruptly in the Gulf of Aqaba (21.4–21.6◦C, and 40.6–40.7 PSU). A well-developed cyclonic gyre with a diameter of about 50–60 km and maximum velocity of about 0.4 m s−1 was observed in the stratified upper 200 m of the northern Red Sea waters. The gyre may contribute to the preconditioning for intermediate water formation in the northern Red Sea

Nutrient flux fuels the summer primary productivity in the oligotrophic waters of the Gulf of Aqaba, Red Sea

The thermohaline characteristics of the Gulf of Aqaba, Red Sea, depict a welldefined seasonal pattern of winter mixing from December to April and summer stratification from May to November. This thermohaline structure is a major controlling factor of the nutrient, chlorophyll a and primary productivity seasonal cycles. The nitrate and chlorophyll a concentration records generated down to 200 m at a vertical resolution of 25 m – weekly during 1994, 1995 and every two weeks from April 1997 through to December 2000 – are employed to assess the nitrogen flux across the summer thermocline of the Gulf of Aqaba. The flux calculations are based on a simple diffusion model that incorporates the physical stress eddy diffusivity factor Kz and a biological stress factor k. Both Kz and k are calculated using the Michaelis-Menten equation and the nitrate concentration gradient. The total nitrate flux of the Gulf of Aqaba during the seven summer months (May–November) is estimated at 0.52 moleN m−2. In relation to established primary productivity values (75.5 gC m−2 (May November)−1) and the generated chlorophyll a records, this yields an f fraction of new to total primary production of 0.50. This relatively high f value is discussed with respect to the geophysical characteristics of the Gulf of Aqaba and similar oceanic basins. The remaining 50% is accounted for by cross-sectional flow from the relatively nutrientrich coral reef coastal habitat and rapid recycling, triggered by high irradiance and water temperature

Yoga as a treatment for vasovagal syncope: A systematic review and meta-analysis

Background: Yoga therapy is being used for vasovagal syncope (VVS). However, there is no sufficient evidence. We aimed to evaluate the effect of yoga as an adjunct to the standard therapy on patients with recurrent VVS. Methods: Electronic databases were systematically searched to collect studies assessing the clinical effects of yoga along with guideline-directed treatment in patients with recurrent VVS. The outcomes were the number of VVS attacks and quality of life (QoL) assessment by Syncope Functional Status Questionnaire (SFSQ) scores at 12 months. We used the Mantel- Haenszel random-effects model to calculate the mean difference (MD) and 95% confidence interval (CI). We used The Cochrane Collaboration Risk of Bias Tool and Newcastle-Ottawa Scale for risk of bias assessment. Results: Four studies were included, two RCTs and two observational studies. The total of participants was 309, with a mean age of 36.4 ± 13.5 years. The male participants represented 141 (45.6%) being males. The baseline syncope burden was 3.5 ± 2.38 episodes over 15.6 ± 12.8 months. Yoga therapy significantly reduced the number of episodes of syncope and presyncope compared to the control group (MD -1.86; 95% CI -3.30, −0.43; P = 0.01). Nevertheless, yoga therapy did not show significant improvement in the QoL assessed by SFSQ scores (MD -30.69; 95% CI -62.22,0.83; P = 0.06). Conclusion: Yoga therapy is a useful lifestyle intervention that can reduce the frequency of syncope and presyncope among patients with recurrent VVS. However, higher-quality RCTs are needed to confirm our results

Physical and chemical properties of seawater during 2013–2015 in the 400 m water column in the northern Gulf of Aqaba, Red Sea

This research investigated physical (temperature, salinity, and density) and chemical (dissolved oxygen, ammonium, nitrate, nitrite, phosphate, and silicate) properties of offshore seawater in the Red Sea northern Gulf of Aqaba; Jordanian Site were measured during 2013–2015 to assess the temporal and seasonal variation of the upper 400 m of the water column. The study also investigated seasonal variations, assessing the relationships of temperature with physical and chemical parameters. The average value of temperature for all data was 23.03 ± 1.58 °C. Temperature followed an expected seasonal cycle during 2013–2015, with well-mixed conditions in the upper 400 m of the water column during spring (Feb–Apr) and stratification during summer (Jul–Aug). There were no significant differences among years for temperature, but highly significant differences among months and depths. The average value of salinity (psu) for all data was 40.60 ± 0.10 with significant positive or negative differences among years, months, and depths. In general, dissolved oxygen, ammonium, nitrate, nitrite, and phosphate data showed positive or negative significant differences among months and depths with no significant annual variations. Silicate only showed significant differences among depths. Correlation tests between temperature and other parameters in the upper 25 m of the water column revealed significant inverse-relationships between temperature and all other parameters (other than salinity) that were attributed to the dominant thermal controls on seawater density, to the thermodynamic controls on oxygen solubility and to seasonal increases in light irradiance that allowed nutrient consumption by primary producers. In the intermediate water column (100–150 m), similar correlations were found as in the 0–25 m data, except for silicate. In the deeper waters (300–400 m), only salinity, density, and phosphate showed significant correlations with temperature, and indicated that the seasonal effects of primary production at depth were minimal. In general, the values of all parameters during the years 2013–2015 in the upper 400 m were comparable with previous studies (e.g., 1998–2003). In conclusion, this research manifested the strong correlation of temperature with some chemical parameters and presumed seasonal controls on primary production. Given the general lack of interannual variation, water quality in the northern Gulf of Aqaba appears relatively stable

Multi-task temporal convolutional network for predicting water quality sensor data

Predicting the trend of water quality is essential in environmental management decision support systems. Despite various data-driven models in water quality prediction, most studies focus on predicting a single water quality variable. When multiple water quality variables need to be estimated, preparing several data-driven models may require unaffordable computing resources. Also, the changing patterns of several water quality variables can only be revealed by processing long term historical observations, which is not well supported by conventional data-driven models. In this paper, we propose a multi-task temporal convolution network (MTCN) for predicting multiple water quality variables. The temporal convolution offers one the capability to explore the temporal dependencies among a remarkably long historical period. Furthermore, instead of providing predictions for only one water quality variable, the MTCN is designed to predict multiple water quality variables simultaneously. Data collected from the Burnett River, Queensland is used to evaluate the MTCN. Compared to training a set of single-task TCNs for each variable separately, the proposed MTCN achieves the best RMSE scores in predicting both temperature and DO in the following 48 time steps but only requires 53% of the total training time of the TCN. Therefore, the MTCN is an encouraging approach for water quality management by processing a large amount of sensor data