A study of the entanglement in systems with periodic boundary conditions

We define the local periodic linking number, LK, between two oriented closed or open chains in a system with three-dimensional periodic boundary conditions. The properties of LK indicate that it is an appropriate measure of entanglement between a collection of chains in a periodic system. Using this measure of linking to assess the extent of entanglement in a polymer melt we study the effect of CReTA algorithm on the entanglement of polyethylene chains. Our numerical results show that the statistics of the local periodic linking number observed for polymer melts before and after the application of CReTA are the same.Comment: 11 pages, 11 figure

Managing oceanographic data collated from on-line Information Systems

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Taphonomical observations on the pygmy hippopotamus site in Aghia Napa, Cyprus.

Στην εργασία αυτή παρουσιάζονται τα αποτελέσματα ταφονομικής ανάλυσης της Άνω πλειστοκαινικής θέσης της Αγίας Νάπας στην Κύπρο. Η πανίδα της απολιθωματοφόρου θέσης κυριαρχείται από σκελετικό υλικό νάνων ιπποπόταμων του είδους Phanourios minor, και εντοπίζεται κάτω από ένα φυσικό στέγαστρο εντός των ασβεστολιθικών σχηματισμών της περιοχής. Η εμφάνιση εκτείνεται σε μια περιοχή περίπου 72 τ.μ. από την οποία έχει συλλεχθεί ιδιαίτερα μεγάλος αριθμός ευρημάτων που υποδεικνύει την ύπαρξη περισσότερων από 160 ιπποπόταμων στη θέση. Στόχο της μελέτης αποτελεί και η απόδοση της αυξημένης συσσώρευσης του οστεολογικού υλικού σε συγκεκριμένους μηχανισμούς, εστιάζοντας στους παλαιοπεριβαλλοντικούς παράγοντες που πιθανά έχουν επηρεάσει και την επιβίωση του. Η ανάλυση στηρίζεται και σε παραμέτρους που μας πληροφορούν σχετικά με την αντιπροσώπευση και άρα την επιβίωση των διαφόρων σκελετικών στοιχείων. Η μελέτη του υλικού ανέδειξε την ύπαρξη λείανσης, κατακερματισμού και σημαντικής θραύσης, φαινόμενα που σχετίζονται με τον τύπο, το μέγεθος και το σχήμα των σκελετικών στοιχείων. Η συσσώρευση του υπό μελέτη υλικού ερμηνεύεται ως αποτέλεσμα φυσικής μεταφοράς τους στη θέση από την γύρω περιοχή, ενώ ο ρόλος του ανθρώπου σε αυτήν είναι ακόμη υπό διερεύνηση. In this paper data concerning the taphonomy of the Upper Pleistocene site Aghia Napa in Cyprus is presented. The site is dominated by skeletal material belonging to the pygmy Hippopotamus species Phanourios minor, and consists a littoral rockshelter. The fossiliferous assemblage is spread in a total area of about 72 m2 and a significantly large number of specimens were collected, indicating the presence of more than 160 individuals at the site. In this paper, we attempt to identify the causes or mechanisms that led to the accumulation of the endemic hippopotamus remains, focusing also on the palaeo-environmental parameters that might had affected the survivorship of the fossils. The taphonomical analysis is also based on parameters, which provide information concerning skeletal element representation and thus survivorship. The study of the skeletal material shows signs of abrasion, cracking and significant fragmentation which are related to the type, size and shape of the skeletal elements. The bone assemblage is interpreted as a result of transportation of the skeletal material from longer or shorter distances in the surrounding area while the impact of man concerning their accumulation is still under discussion

Clinical Impact of a Novel Interprofessional Dental and Pharmacy Student Tobacco Cessation Education Program on Dental Patients

Objectives: • To compare the difference between IPE care and standard care (SC) groups regarding dental patients\u27 perceptions of knowledge gained about tobacco cessation, intentions to quit tobacco use, and quit attempts at follow-up. • To evaluate perceptions of IPE care. Background: Based on the link between tobacco use and oral health and the frequent contact between dental providers and patients, the dental clinic is an ideal setting to address tobacco use.1 • Many dentists feel unprepared providing tobacco cessation education, particularly pharmacologic treatment options.1-3 • Pharmacists promote safe and effective pharmacologic treatment options for tobacco dependence and patients’ perceptions toward pharmacist-provided tobacco cessation education have been positive.4-6 • A novel interprofessional education (IPE) program involving dental and pharmacy students may address the need for tobacco cessation education in the dental clinic setting

A step-by-step diagnosis of exclusion in a twin pregnancy with acute respiratory failure due to non-fatal amniotic fluid embolism: a case report

<p>Abstract</p> <p>Introduction</p> <p>Respiratory failure may develop during the later stages of pregnancy and is usually associated with tocolysis or other co-existing conditions such as pneumonia, sepsis, pre-eclampsia or amniotic fluid embolism syndrome.</p> <p>Case presentation</p> <p>We present the case of a 34-year-old healthy woman with a twin pregnancy at 31 weeks and 6 days who experienced acute respiratory failure, a few hours after administration of tocolysis (ritodrine), due to preterm premature rupture of the membranes. Her chest discomfort was significantly ameliorated after the ritodrine infusion was stopped and a Cesarean section was performed 48 hours later under spinal anesthesia; however, 2 hours after surgery she developed severe hypoxemia, hypotension, fever and mild coagulopathy. The patient was intubated and transferred to the intensive care unit where she made a quick and uneventful recovery within 3 days. As there was no evidence for drug- or infection-related thromboembolic or myocardial causes of respiratory failure, we conclude that our patient experienced a rare type of non-fatal amniotic fluid embolism.</p> <p>Conclusion</p> <p>In spite of the lack of solid scientific support for our diagnosis, we conclude that our patient suffered an uncommon type of amniotic fluid embolism syndrome and we believe that this report highlights the need for extreme vigilance and a high index of suspicion for such a diagnosis in any pregnant individual.</p

Responses of Lotus corniculatus to environmental change 3:The sensitivity of phenolic accumulation to growth temperature and light intensity and effects on tissue digestibility

The response of plant growth, phenolic accumulation and tissue digestibility to light and temperature was determined in clonal plants of three genotypes of Lotus corniculatus (birdsfoot trefoil) cv Leo, with low, intermediate or high levels of proanthocyanidins (condensed tannins). Plants were grown from 10 °C to 30 °C, or at light intensities from 20 to 500 µm m−2 s−1. Plants grown at 25 °C had the highest growth rate and highest digestibility, whereas the maximum tannin concentration was found in plants grown at 15 °C. Approximately linear increases in leaf flavonol glycoside levels were found with increasing growth temperature in the low tannin genotype. Tannin hydroxylation increased with increasing growth temperature but decreased with increasing light intensity. The major leaf flavonols were kaempferol glycosides of which kaempferol-3-glucoside and kaempferol-3,7-dirhamnoside were the major components. Increases in both tannin and total flavonol concentrations in leaves were linearly related to light intensity and were preceded by a specific increase in the transcript level of a non-legume type chalcone isomerase. Changes in growth temperature and light intensity, therefore, result in major changes in the partitioning of carbon into phenolics, which significantly affects tissue digestibility and nutritional quality with a high correlation between tannin concentration and leaf digestibility

Numerical renormalization-group study of spin correlations in one-dimensional random spin chains

We calculate the ground-state two-spin correlation functions of spin-1/2 quantum Heisenberg chains with random exchange couplings using the real-space renormalization group scheme. We extend the conventional scheme to take account of the contribution of local higher multiplet excitations in each decimation step. This extended scheme can provide highly accurate numerical data for large systems. The random average of staggered spin correlations of the chains with random antiferromagnetic (AF) couplings shows algebraic decay like $1/r^2$, which verifies the Fisher's analytic results. For chains with random ferromagnetic (FM) and AF couplings, the random average of generalized staggered correlations is found to decay more slowly than a power-law, in the form close to $1/\ln(r)$. The difference between the distribution functions of the spin correlations of the random AF chains and of the random FM-AF chains is also discussed.Comment: 14 pages including 8 figures, REVTeX, submitted to Physical Review

The effect of combined supplementation of carbohydrates and creatine on anaerobic performance.

The purpose of the study was to examine the effect of creatine (Cr) supplementation on anaerobic performance when ingesting creatine and carbohydrates (CHO) together. Twenty male physical education students comprised the two experimental (CR and CRCHO) and one control (CON) groups of the study. All groups performed three 30 s anaerobic Wingate tests (AWTs) interspersed with 6 minutes of recovery. The CR group (n = 7) ingested 5 g of Cr 5 times per day for 4 days. Subjects in the CRCHO group (n = 6) ingested the same quantity but additionally after each 5 g dose of Cr consumed 500 ml of a commercially available energy drink containing 100 g of simple sugars. Over all three AWTs average mean power improved significantly compared to baseline for the CR group (5.51%) but not for the CRCHO group (3.06%). Mean power for the second AWT was improved following the acute loading for the CR group only (4.54%) and for the third AWT for both CR (8.49%) and CRCHO (5.75%) groups. Over all three AWTs a significant change was recorded in average peak power following the acute loading for the CR group (8.26%) but not for the CRCHO group (4.11%). Peak power was significantly improved following the loading only for the CR group during the third AWT (19.79%). No changes in AWT performance were recorded for the CON group after intervention. The findings of the present study suggest that ingesting creatine together with carbohydrates will not further improve performance compared to the ingestion of creatine only