Dimensioning Links for IP Telephony

Transmitting telephone calls over the Internet causes problems not present in current telephone technology such as packet loss and delay due to queueing in routers. In this undergraduate thesis we study how a Markov modulated Poisson process is applied as an arrival process to a multiplexer and we study the performance in terms of loss probability. The input consists of the superposition of independent voice sources. The predictions of the model is compared with results obtained with simulations of the multiplexer made with a network simulator. The buffer occupancy distribution is also studied and we see how this distribution changes as the load increases

Change in Function, Pain and Quality of Life following Structured Nonoperative Treatment in Patients with Degenerative Cervical Myelopathy: A Systematic Review

Title: Change in Function, Pain and Quality of Life following Structured Nonoperative Treatment in Patients with Degenerative Cervical Myelopathy: A Systematic Review Authors: Lindsay Tetreault1, Mohammed Shamji1, John Rhee2, Heidi Prather3, Jeff Wilson1, Ian B. Andersson4, Anna H. Dembek4, Krystle Pagarigan5, Joseph R. Dettori5, Michael G. Fehlings1 Affiliations: 1. Toronto Western Hospital, Toronto 2. Emory clinic, Atlanta 3. School of Medicine, Washington University at St. Louis 4. School of Physical Therapy, University of Puget Sound 5. Spectrum Research, Tacoma Purpose: To perform a systematic review of the current literature to analyze (1) the change in pain, function, and quality of life resulting from structured nonoperative treatment for degenerative cervical myelopathy (DCM); (2) the variability of change in function, pain and quality of life after different nonoperative treatments; (3) the differences in outcomes observed among subgroups (i.e baseline severity score, duration of symptoms); and (4) negative outcomes and harms resulting from physical therapy intervention. Materials and Methods: A systematic search was conducted in Embase, the Cochrane Collaboration, and PubMed for research published between January 1, 1950 and February 9, 2015. Articles were included if they evaluated outcomes related to structured nonoperative treatment, including manual therapy, therapeutic exercise, cervical bracing and/or traction. Outcomes of interest include functional status (Japanese Orthopedic Association (JOA), Nurick), upper extremity and neck pain, quality of life (Neck Disability Index), and/or surgical intervention. The quality of each study was assessed using the Newcaste-Ottawa Scale and the strength of evidence was rated using guidelines from the Grading of Recommendation Assessment, Development and Evaluation Working Group. Results: Of the 570 citations, eight met the criteria for inclusion in this review. There is very low evidence implying that structured nonoperative treatment for DCM garners a positive or negative change in pain, function, and quality of life as interpreted by the JOA score. There is also limited evidence from three studies showing that early nonoperative treatment (symptoms \u3c1 year) is associated with positive clinical outcomes. No studies directly compared structured nonoperative treatment types nor explored outcomes based on patient subgroups. The incidence of conversion to surgery ranged from 23-54%; primarily involving cases of mild or moderate myelopathy (JOA≥12). Conclusion: There is a general lack of evidence to discern the role of nonoperative treatment for patients with DCM. In the majority of studies, however, patients did not achieve clinically significant gains in functional status with structured nonoperative treatment. Rates of failed conservative treatment among all included studies were between 23-54%. Clinical Relevance: The role of structured nonoperative treatment for the management of DCM is not well defined, and the typical recommendation for patients with moderate to severe DCM is surgical intervention. References: Fehlings MG, Ibrahim A, Tetreault L, et al. A Global Perspective on the Outcomes of Surgical Decompression in Patients with Cervical Spondylotic Myelopathy: Results from the Prospective Multicenter AOSpine International Study on 479 patients. Spine. 2015. Nurick S. The natural history and the results of surgical treatment of the spinal cord disorder associated with cervical spondylosis. Brain : a journal of neurology. 1972;95(1):101-108. Nouri A, Tetreault L, Singh A, Karadimas SK, Fehlings MG. Degenerative Cervical Myelopathy: Epidemiology, Genetics, and Pathogenesis. Spine. 2015;40(12):E675-693. Key Words: cervical myelopathy, degenerative myelopathy, nonsurgical management, nonoperative, conservative, physical therapy, manual therapy, therapeutic exercise, cervical traction, OPLL, spondylotic myelopathy, cervical stenosi

The dynamical tides of spinning Newtonian stars

We carefully develop the framework required to model the dynamical tidal response of a spinning neutron star in an inspiralling binary system, in the context of Newtonian gravity, making sure to include all relevant details and connections to the existing literature. The tidal perturbation is decomposed in terms of the normal oscillation modes, used to derive an expression for the effective Love number which is valid for any rotation rate. In contrast to previous work on the problem, our analysis highlights subtle issues relating to the orthogonality condition required for the mode-sum representation of the dynamical tide and shows how the prograde and retrograde modes combine to provide the overall tidal response. Utilising a slow-rotation expansion, we show that the dynamical tide (the effective Love number) is corrected at first order in rotation, whereas in the case of the static tide (the static Love number) the rotational corrections do not enter until second order.PP acknowledges support from the María Zambrano Fellowship Programme (ZAMBRANO21), funded by the Spanish Ministry of Universities and the University of Alicante through the European Union’s “Next Generation EU” package, as well as from the grant PID2021-127495NBI00, funded by MCIN/AEI/10.13039/501100011033 and by the European Union, from the Astrophysics and High Energy Physics programme of the Generalitat Valenciana ASFAE/2022/026, funded by the Spanish Ministry of Science and Innovation (MCIN) and the European Union’s “Next Generation EU” package (PRTR-C17.I1), and from the Prometeo 2023 excellence programme grant CIPROM/2022/13, funded by the Ministry of Innovation, Universities, Science, and Digital Society of the Generalitat Valenciana. This work was also supported by the “Ministero dell’istruzione, dell’università e della ricerca" (MIUR) PRIN 2017 programme (CUP: B88D19001440001), from the Amaldi Research Center, funded by the MIUR programme “Dipartimento di Eccellenza" (CUP: B81I18001170001), and from the EU Horizon 2020 Research and Innovation Programme under the Marie Skłodowska-Curie Grant Agreement N. 101007855. FG, NA, and DIJ are grateful for support from STFC via grant numbers ST/R00045X/1 and ST/V000551/1

Assessment of Breast Milk Iodine Concentrations in Lactating Women in Western Australia

Breast-fed infants may depend solely on an adequate supply of iodine in breast milk for the synthesis of thyroid hormones which are essential for optimal growth and cognitive development. This is the first study to measure breast milk iodine concentration (BMIC) among lactating women in Western Australian (n = 55). Breast milk samples were collected between 2014 and 2015 at a mean (±SD) of 38.5 (±5.5) days post-partum. The samples were analysed to determine median BMIC and the percentage of samples with a BMIC < 100 μg/L, a level considered adequate for breast-fed infants. The influence of (a) iodine-containing supplements and iodised salt use and (b) consumption of key iodine-containing foods on BMIC was also examined. The median (p25, p75) BMIC was 167 (99, 248) μg/L and 26% of samples had a BMIC < 100 μg/L. Overall, BMIC tended to be higher with iodine-containing supplement usage (ratio 1.33, 95% confidence interval (CI) (1.04, 1.70), p = 0.030), cow’s milk consumption (ratio 1.66, 95% CI (1.23, 2.23), p = 0.002) and lower for Caucasians (ratio 0.61, 95% CI (0.45, 0.83), p = 0.002), and those with secondary school only education (ratio 0.66, 95% CI (0.46, 0.96), p = 0.030). For most women, BMIC was adequate to meet the iodine requirements of their breast-fed infants. However, some women may require the use of iodine-containing supplements or iodised salt to increase BMIC to adequate levels for optimal infant nutrition

Ultra-high-resolution observations of CH in southern molecular cloud envelopes

We present a mini‐survey of ultrahigh‐resolution spectroscopy (UHRS) of CH towards three southern molecular cloud envelopes. The sightlines are selected to probe physically similar gas in different Galactic environments. With a velocity resolution of ∼0.5 km s−1(R=575 000) these observations resolve most kinematic components of the absorption lines. We do, however, detect one line component in the Lupus region, which is not resolved and for which an upper limit of b<0.3 km s‐1 is found. We find a correlation between distance of the absorbing gas from the Galactic mid‐plane and the fractional abundance of CH. We show that this correlation can be explained as being a result of a fall‐off in the ultraviolet radiation field intensity and propose that CH observations in carefully selected sightlines might allow a mapping of the variations in the interstellar radiation field

Determining the variation in premaxillary and dentary bone morphology that may underlie beak shape between two pure layer lines

ABSTRACT: Beak treatment is an effective method of reducing the damage inflicted by severe feather pecking (SFP) but there is significant pressure to eliminate these treatments and rely solely on alternative strategies. Substantial variation in beak shape exists within non-beak treated layer flocks and beak shape appears to be heritable. There is the potential to use this pre-existing variation and genetically select for hens whose beak shapes are less apt to cause damage during SFP. To do this, we must first understand the range of phenotypes that exist for both the external beak shape and the bones that provide its structure. The objective of this study was to determine the variation in premaxillary (within the top beak) and dentary (within the bottom beak) bone morphology that exists in 2 non-beak treated pure White Leghorn layer lines using geometric morphometrics to analyze radiographs. Lateral head radiographs were taken of 825 hens and the premaxillary and dentary bones were landmarked. Landmark coordinates were standardized by Procrustes superimposition and the covariation was analyzed by principal components analysis and multivariate regression using Geomorph (an R package). Three principal components (PCs) explained 85% of total premaxillary bone shape variation and showed that the shape ranged from long and narrow with pointed bone tips to short and wide with more curved tips. Two PCs explained 81% of total dentary bone shape variation. PC1 described the dentary bone length and width and PC2 explained the angle between the bone tip and its articular process. For both bones, shape was significantly associated with bone size and differed significantly between the two lines. Bone size accounted for 42% of the total shape variation for both bones. Together, the results showed a range of phenotypic variation in premaxillary and dentary bone shape, which in turn may influence beak shape. These bone phenotypes will guide further quantitative genetic and behavioral analyses that will help identify which beaks shapes cause the least damage when birds engage in SFP

The gains from preferential tax regimes reconsidered

The EU policy against harmful tax competition aims at eliminating tax policies targeted at attracting the internationally mobile tax base. We construct an imperfectly competitive model of costly trade between two countries. In setting their corporate taxes, governments non-cooperatively decide whether to discriminate between internationally mobile and immobile firms. We find the Nash equilibrium tax regimes. When trade costs are high countries impose a uniform tax on all firms while nations will discriminate between mobile and immobile firms when costs are low. At some trade costs, fiscal competition results in tax discrimination despite uniform taxation being socially preferable

Heparin molecularly imprinted surfaces for the attenuation of complement activation in blood

Heparin-imprinted synthetic polymer surfaces with the ability to attenuate activation of both the complement and the coagulation system in whole blood were successfully produced. Imprinting was achieved using a template coated with heparin, a highly sulfated glycosaminoglycan known for its anticoagulant properties. The N,N'-diacryloylpiperazine-methacrylic acid copolymers were characterized using goniometry, AFM and XPS. The influence of the molecular imprinting process on morphology and template rebinding was demonstrated by radioligand binding assays. Surface hemocompatibility was evaluated using human whole blood without anticoagulants followed by measurement of complement activation markers C3a and sC5b-9 and platelet consumption as a surrogate coagulation activation marker. The observed low thrombogenicity of this copolymer combined with the attenuation of complement activation induced by the molecular imprint offer potential for the development of self-regulating surfaces with important potential clinical applications. We propose a mechanism for the observed phenomena based upon the recruitment of endogenous sulfated glycosaminoglycans with heparin-like activities

Bridging the Gap Between Science, Economics and Policy to Develop and Implement a Pilot Market Based Instrument for Soil Carbon

Increasing soil organic carbon (SOC) has potential to offset greenhouse gas emissions, but the scope for on-farm carbon sequestration is poorly understood. A pilot scheme was developed in Central West NSW, Australia to trial the use of a market-based instrument to encourage farmers to increase soil organic carbon levels. The pilot considered the relationship between land use, management practices and soil carbon levels; offered alternative contract designs to attract landholders; and developed monitoring and reporting protocols. The pilot was rolled-out in 2011 and 2012 and had 11 successful tenders with an average price of $A37 per t CO2-e. The results of this conservation tender will assist the design of future programs aimed at encouraging mitigation effort from the agricultural sector

The impact of early outcome events on the effect of tranexamic acid in post-partum haemorrhage: an exploratory subgroup analysis of the WOMAN trial.

BACKGROUND: In severe post-partum haemorrhage, death can occur within hours of bleeding onset so interventions to control the bleeding must be given immediately. In clinical trials of treatments for life-threatening bleeding, established treatments are given priority and the trial treatment is usually given last. However, enrolling patients in whom severe maternal morbidity or death is imminent or inevitable at the time of randomisation may dilute the effects of a trial treatment. METHODS: We conducted an exploratory analysis of data from the WOMAN trial, an international, randomised placebo-controlled trial of the effects of tranexamic acid on death and surgical intervention in 20,060 women with post-partum haemorrhage. We assessed the impact of early maternal death or hysterectomy due to exsanguination on the effect of tranexamic acid on each of these respective outcomes. We conducted repeated analyses excluding patients with these outcomes at increasing intervals from the time of randomisation. We quantified treatment effects using risk ratios (RR) and 99% confidence intervals (CI) and prepared cumulative failure plots. RESULTS: Among 14,923 women randomised within 3 h of delivery (7518 tranexamic acid and 7405 placebo), there were 216 bleeding deaths (1.5%) and 383 hysterectomies due to bleeding (2.8%). After excluding deaths from exsanguination at increasing time intervals following randomization, there was a significant reduction in the risk of death due to bleeding with tranexamic acid (RR = 0.41; 99% CI 0.19-0.89). However, after excluding hysterectomies at increasing time intervals post-randomization, there was no reduction in the risk of hysterectomy due to bleeding with tranexamic acid (RR = 0.79; 99% CI 0.33-1.86). CONCLUSIONS: Findings from this analysis provide further evidence that tranexamic acid reduces the risk of death from exsanguination in women who experience postpartum haemorrhage. It is uncertain whether tranexamic acid reduces the risk of hysterectomy for bleeding after excluding early hysterectomies. TRIAL REGISTRATION: ISRCTN trial registration number ISRCTN76912190, 8 Dec 2008; ClinicalTrials.gov number NCT00872469, 30 March 2009; PACTR number PACTR201007000192283, 9 Feb 2010; EudraCT number 2008-008441-38, 8 Dec 2010 (retrospectively registered)