Modeling and identification of an RRR-robot

A dynamic model of a robot with 3 rotational degrees of freedom is derived in closed form. A systematic procedure for estimation of model dynamic parameters is suggested. It consists of the following steps: (i) identification of friction model parameters for each joint; (ii) calculation of optimal exciting trajectories, required for estimation of the remaining dynamic model parameters; (iii) estimation of these parameters using a least-squares method. The estimated model satisfactory reconstructs experimental control signals, justifying its use in model-based nonlinear control

Insecticidal Activity of Sage (Salvia Officinalis) Essential Oil to Varroa Destructor (Acari: Varroidae) and Apis Mellifera (Hymenoptera: Apidae)

The need to find alternative systems of the fight against Varroa mite without application of chemicals and provide healthy bee products resulted in investigation of application of different plant essences to arthropod control. In order to perceive the sage essential oil (Salvia officinalis) bioactivity, contact residual toxicity of mites and bees was examined in the laboratory conditions. The chemical composition of essential oil was determined by standard GC and GC/MS methods. Different doses of the sage essential oil dissolved in acetone (0.1–10 μl/Petri dish) were applied in Petri dishes and left to dry for 20 minute at a room temperature. Following this period of time, ten honey bees and five adult female mites were added in each Petri dish and they were all maintained in controlled conditions (T = 30°C, Relative humidity = 60%). Survival of examined honey bees and Varroa mites was recorded two times, after 24 h and 48 h. The most prominent toxic effect on the examined Varroa mites was observed after 24 h and 48 h, with application of 10 μl of sage oil (the average values for dead mite individuals were 3.25 and 3.50, respectively). Recorded biological activities of the oil tested in different doses on both honey bee and Varroa mite revealed opportunity to proceed with further investigation by selecting the most appropriate variants and combinations of the most prominent individual components of the examined sage oil

Role of recombinant factor VIIa in the treatment of intractable bleeding in vascular surgery

BackgroundMost recent publications have shown that the recombinant form of activated factor VII (rFVIIa; NovoSeven, Novo Nordisk A/S, Bagsværd, Denmark) induces excellent hemostasis in patients with severe intractable bleeding caused by trauma and major surgery. The purpose of this study was to determine the influence of rFVIIa on the treatment of intractable perioperative bleeding in vascular surgery when conventional hemostatic measures are inadequate.Materials and MethodsThere were two groups of patients: the NovoSeven group (group N), 10 patients with ruptured abdominal aortic aneurysms (RAAAs) and 14 patients operated on due to thoracoabdominal aortic aneurysms (TAAAs); the control group (group C), 14 patients with RAAAs and 17 patients with TAAAs. All patients suffered intractable hemorrhage refractory to conventional hemostatic measures, while patients from group N were additionally treated with rFVIIa.ResultsPostoperative blood loss was significantly lower in group N treated with rFVII (P < .0001). Postoperative administration of packed red blood cells, fresh frozen plasma, and platelets was lower in patients from group N, (P < .0001). Successful hemorrhage arrest was reported in 21 patients (87.5%) treated with rFVIIa, and in 9 patients (29.03%) in group C (P < .001). Thirty-day mortality in these two groups significantly differed. The mortality rate was 12.5% (3 patients) in group N and 80.65% (25 patients) in group C (P < .0001).ConclusionOur findings suggest that rFVIIa may play a role in controlling the intractable perioperative and postoperative bleeding in surgical patients undergoing a repair of RAAAs and TAAAs. Certainly, prospective randomized trials are necessary to further confirm the efficacy and cost-effectiveness of rFVIIa in these patients

Techno-functional, textural and sensorial properties of frankfurters as affected by the addition of bee pollen powder

The objective of this study was to determine whether the addition of different pollen powder concentrations (0.5; 1.0 and 1.5 g/100 g) had an influence on techno-functional, textural and sensorial traits of frankfurters. Examining the techno-functional characteristics of pollen, a conclusion was reached that the higher the concentration, the higher the emulsification and better techno-functional properties. Also, FTIR-ATR analysis has shown that specific pollen molecules provided good emulsifying properties of sausages. On the other hand, sensory analysis showed that sausages with the addition of 1.0% and 1.5% of pollen powder have a more pronounced floral odor. Warner-Bratzler shear force test has shown that the incorporation of pollen caused a more stable product throughout sixty days of storage than the control sample. It could be explained by the formation of more protein-protein interactions due to the addition of non-meat proteins in the formulation of frankfurters and obtaining a more stable product than the control one. All things considered, it can be concluded that pollen exhibits good techno-functional properties and could be utilized in the formulation of frankfurters with improved and steady techno-functional properties during two months of refrigerated storage

Paramagnetic Meissner Effect in Multiply-Connected Superconductors

We have measured a paramagnetic Meissner effect in Nb-Al2O3-Nb Josephson junction arrays using a scanning SQUID microscope. The arrays exhibit diamagnetism for some cooling fields and paramagnetism for other cooling fields. The measured mean magnetization is always less than 0.3 flux quantum (in terms of flux per unit cell of the array) for the range of cooling fields investigated. We demonstrate that a new model of magnetic screening, valid for multiply-connected superconductors, reproduces all of the essential features of paramagnetism that we observe and that no exotic mechanism, such as d-wave superconductivity, is needed for paramagnetism.Comment: 4 pages, 3 figures, LaTe

A rapid and reliable determination of doxycycline hyclate by HPLC with UV detection in pharmaceutical samples

An accurate, sensitive and reproducible high performance liquid chromatographic (HPLC) method for the quantification of doxycycline hyclate in pharmaceutical samples has been developed and validated. The drug and the standard were eluted from a Lichrosorb RP-8 (250 mm´4.6 mm, 10 mm particle size) at 20 °C with a mobile phase consisting of methanol, acetonitrile and 0.010 M aqueous solution of oxalic acid (2:3:5, v/v/v). The flow rate was 1.25 ml min-1. A UV detector set at 350 nm was used to monitor the effluent. Each analysis required no longer than 4 min. The limits of detection and quantification were 1.15 and 3.84 μg ml-1, respectively. Recoveries for different concentrations ranged from 99.58 to 101.93 %

Having Fun in Learning Formal Specifications

There are many benefits in providing formal specifications for our software. However, teaching students to do this is not always easy as courses on formal methods are often experienced as dry by students. This paper presents a game called FormalZ that teachers can use to introduce some variation in their class. Students can have some fun in playing the game and, while doing so, also learn the basics of writing formal specifications in the form of pre- and post-conditions. Unlike existing software engineering themed education games such as Pex and Code Defenders, FormalZ takes the deep gamification approach where playing gets a more central role in order to generate more engagement. This short paper presents our work in progress: the first implementation of FormalZ along with the result of a preliminary users' evaluation. This implementation is functionally complete and tested, but the polishing of its user interface is still future work

Phenolic Profile and Antioxidant Activity of Pulp and Peel from Peach and Nectarine Fruits

Peach (Prunus persica L.) is a fruit of high nutritional and economic value. Carbohydrates, dietary fibers, minerals and organic acids are among the major constituents of peach fruit, which contribute to the nutritional quality of both fresh fruits and juice. Polyphenolic compounds found in peach may play an important role in physiological functions related to human health. Different polyphenolics may have varied biological activities including antioxidant activity. In this study antioxidant characteristics between peel and pulp of different peach cultivars (‘RadmilovÄanka’, ‘June Gold’, ‘Blake’, ‘Hale’, ‘Vesna’, ‘Adria’) and one of nectarine (‘Fantasia’) were investigated. The peel and pulp extracts showed a huge amount of total phenolics (TP), total flavonoids (TF), total hydroxycinnamates (TH) and total flavonols (TFL), ranging from 42.7-211.4, 11.1-128.5 mg GAE/100 g fresh weight (f.w.) (TP), 21.9 -94.9, 5.0-58.9 mg CE/100 g f.w. (TF), 28.4-389.2, 8.5-165.8 mg kg-1 f.w. (TH) and 17.3-54 mg kg-1 f.w. (TFL). High contents of phenolic compounds were significantly correlated with high antioxidant capacities. Peach pulp and peel differ significantly in their phenolic profiles: the pulp contains mainly chlorogenic, neochlorogenic and p-coumaric acids, whereas the peel possesses chlorogenic, neochlorogenic and p-coumaric acids together with several flavonol glycosides in huge amounts. Our results indicate that cultivar and extraction solvent play important roles in phenolic compositions and antioxidant properties of peach and nectarine extracts, which was shown using statistical analysis (ANOVA). There are high correlations between extracted phenolic compounds and peach and nectarine cultivars, and used solvent and part of the fruit (peel and pulp)

Plan integrisanog monitoringa kvaliteta zemljišta kao indikatora kvaliteta životne sredine u Novom Sadu

U radu je prikazan plan integisanog upravljanja životnom sredinom na primeru kontrole kvaliteta zemljišta u gradu Novom Sadu u Republici Srbiji. S obzirom da ima veoma povoljan geografski položaj, Novi Sad je grad gde se prepliću važni magistralni putevi, ima sve veći priliv stanovništva, kao i brzi razvoj industrije i poljoprivrede. Usled navedenih činjenica postoji i povećano zagađivanje vazduha, vode i zemljišta, kao i generisanje velike količine otpada. Pored parkova i devastiranih područja u okolini industrijskih zona, rasprostranjena poljoprivredna delatnost u prigradskim delovima, naročito je osetljiva na kvalitet zemljišta i obrnuto. U ovoj studiji analizirani su geografska pozicija i geomorfološke karakteristike područja grada, kao i vodeći ekološki problemi. Na osnovu datih činjenica predložen je integrisani monitoring jednog od indikatora kvaliteta životne sredine, kvalitet zemljišta. Predložena je mreža od ukupno 15 senzora za merenje pH vrednosti, vlage i temperature zemljišta na teritoriji grada. Podaci o kvalitetu zemljišta koji se na ovakav način dobijaju u realnom vremenu veoma značajni su za eliminisanje ili ublažavanje potencijalnih nepoželjnih posledica. Zahvaljujući brzom razvoju tehnologije primena senzorskih mreža sve više se koristi u modernim sistemima monitoringa i dostupna je za efikasno i ekonomski isplativo rešavanje problema zaštite životne sredine

Using Random Subsets to Build Scalable Network Services

In this paper, we argue that a broad range of large-scale network services would benefit from a scalable mechanism for delivering state about a random subset of global participants. Key to this approach is ensuring that membership in the subset changes periodically and with uniform representation over all participants. Random subsets could help overcome inherent scaling limitations to services that maintain global state and perform global network probing. It could further improve the routing performance of peer-to-peer distributed hash tables by locating topologically-close nodes. This paper presents the design, implementation, and evaluation of RanSub, a scalable protocol for delivering such state. As a first demonstration of the RanSub utility, we construct SARO, a scalable and adaptive application-layer overlay tree. SARO uses RanSub state information tolocate appropriate peers for meeting application-specific delay and bandwidth targets and to dynamically adapt to changing network conditions. A large-scale evaluation of 1000 overlay nodes participating in an emulated 20,000- node wide-area network topology demonstrate both the adaptivity and scalability (in terms of per-node state and network overhead) of both RanSub and SARO. Finally, we use an existing streaming media server to distribute content through SARO running on top of the PlanetLab Internet testbed