Thermal Transients in District Heating Systems

Heat fluxes in a district heating pipeline systems need to be controlled on the scale from minutes to an hour to adjust to evolving demand. There are two principal ways to control the heat flux - keep temperature fixed but adjust velocity of the carrier (typically water) or keep the velocity flow steady but then adjust temperature at the heat producing source (heat plant). We study the latter scenario, commonly used for operations in Russia and Nordic countries, and analyze dynamics of the heat front as it propagates through the system. Steady velocity flows in the district heating pipelines are typically turbulent and incompressible. Changes in the heat, on either consumption or production sides, lead to slow transients which last from tens of minutes to hours. We classify relevant physical phenomena in a single pipe, e.g. turbulent spread of the turbulent front. We then explain how to describe dynamics of temperature and heat flux evolution over a network efficiently and illustrate the network solution on a simple example involving one producer and one consumer of heat connected by "hot" and "cold" pipes. We conclude the manuscript motivating future research directions.Comment: 31 pages, 7 figure

Landmarks in vaginal mesh development: polypropylene mesh for treatment of SUI and POP

Vaginal meshes used in the treatment of stress urinary incontinence (SUI) and pelvic organ prolapse (POP) have produced highly variable outcomes, causing life-changing complications in some patients while providing others with effective, minimally invasive treatments. The risk:benefit ratio when using vaginal meshes is a complex issue in which a combination of several factors, including the inherent incompatibility of the mesh material with some applications in pelvic reconstructive surgeries and the lack of appropriate regulatory approval processes at the time of the premarket clearance of these products, have contributed to the occurrence of complications caused by vaginal mesh. Surgical mesh used in hernia repair has evolved over many years, from metal implants to knitted polymer meshes that were adopted for use in the pelvic floor for treatment of POP and SUI. The evolution of the material and textile properties of the surgical mesh was guided by clinical feedback from hernia repair procedures, which were also being modified to obtain the best outcomes with use of the mesh. Current evidence shows how surgical mesh fails biomechanically when used in the pelvic floor and materials with improved performance can be developed using modern material processing and tissue engineering techniques

Proteomic Analysis of a Noninvasive Human Model of Acute Inflammation and Its Resolution: The Twenty-one Day Gingivitis Model

The 21-day experimental gingivitis model, an established noninvasive model of inflammation in response to increasing bacterial accumulation in humans, is designed to enable the study of both the induction and resolution of inflammation. Here, we have analyzed gingival crevicular fluid, an oral fluid comprising a serum transudate and tissue exudates, by LC−MS/MS using Fourier transform ion cyclotron resonance mass spectrometry and iTRAQ isobaric mass tags, to establish meta-proteomic profiles of inflammation-induced changes in proteins in healthy young volunteers. Across the course of experimentally induced gingivitis, we identified 16 bacterial and 186 human proteins. Although abundances of the bacterial proteins identified did not vary temporally, Fusobacterium outer membrane proteins were detected. Fusobacterium species have previously been associated with periodontal health or disease. The human proteins identified spanned a wide range of compartments (both extracellular and intracellular) and functions, including serum proteins, proteins displaying antibacterial properties, and proteins with functions associated with cellular transcription, DNA binding, the cytoskeleton, cell adhesion, and cilia. PolySNAP3 clustering software was used in a multilayered analytical approach. Clusters of proteins that associated with changes to the clinical parameters included neuronal and synapse associated proteins

Effects of Cryogenic Processing on Rapid Prototyping Materials (DSMSomos-8110 and DuraForm PA)

This research investigates the effects of cryogenic processing on the properties of rapid prototyped materials. Not much research has been done on the post-processing (aging) of rapid prototyped (RP) polymers at temperatures below 159K (–173˚F). Test specimens of RP thermoplastic resin DSM-Somos 8110 and DuraformPA Nylon were fabricated and cryogenically aged from 5-30 hours. The tensile strength and impact toughness were measured. The goal of this work was to study the effect of cryogenic aging on yield strength and ductility. This research investigated (1) the cryogenic aging of DSM-Somos 8110 and DuraformPA Nylon, (2) the effects of controlled ramp-downs/ups on the ultimate and tensile strengths of samples, (3) the experimental methods, and (4) the analysis and interpretation of the data.Part of this work was funded by a NSF Grant under Research Experiences for Undergraduates.Mechanical Engineerin

Alternative job search strategies in remote rural and peri-urban labour markets: the role of social networks

This paper examines the importance of informal methods (especially social networking) to the job search strategies used by unemployed people. It compares three areas: a small rural town; a larger, more sparsely populated, remote rural area; and a centrally-located, peri-urban labour market. The analysis is based first on survey research undertaken with 490 job seekers across the study areas. Emerging issues were then followed up during a series of twelve focus groups. The survey research showed that job seekers in the rural study areas were significantly more likely to use social networks to look for work. However, those who had experienced repeated or long-term periods out of work, the unskilled and young people were significantly less likely to use such networks. Focus groups confirmed the perceived importance of social networking to the job search process in rural areas, in contrast to the more marginal role such methods appear to play in peri-urban settings. For many rural job seekers, formal job search activities conducted through Jobcentres were seen as largely symbolic, lacking the practical value of social networking. These results suggest that service providers seeking to assist unemployed people in rural areas need to address the problems faced by many disadvantaged job seekers who are currently caught between their lack of social network relations and the absence of local public employment service facilities in more remote communities

Darifenacin hydro­bromide

In the title compound {systematic name: (S)-3-[(aminocar­bonyl)diphenylmethyl]-1-[2-(2,3-di­hy­dro­benzofuran-5-yl)ethyl]pyrrolidinium bromide}, C28H31N2O2 +·Br−, the pyrrolidine rings adopts an envelope conformation. The two phenyl rings make a dihedral angle of 72.5 (1)°. The four coplanar atoms of the pyrrolidine ring makes dihedral angles of 33.1 (2) and 82.8 (2)° with the two phenyl rings. The mol­ecular conformation is influenced by a C—H⋯O inter­action. In the crystal packing, there are two N—H⋯Br hydrogen bonds running in opposite directions. They appear to form C(10) and C(9) chain motifs in the unit cell. In addition, the mol­ecular packing is further stabilized by C—H⋯Br and C—H⋯O hydrogen bonds. The C atom bonded to the benzofuran ring system is disordered in a 0.66:0.34 ratio

Social context mediates the expression of a personality trait in a gregarious lizard

The social environment is a key factor that influences behavioural traits across a wide array of species. Yet, when investigating individual differences in behaviour, studies tend to measure animals in isolation from other conspecifics-even in social species. Surprisingly, whether behavioural traits measured in isolation are predictive of individual-level behaviour when in social groups is still poorly understood. Here, we repeatedly measured risk-taking behaviour (i.e. boldness; 741 total trials) in both the presence and absence of conspecifics in a social lizard, the delicate skink (Lampropholis delicata). Further, we manipulated food availability during group trials to test whether the effect of the social environment on risk-taking behaviour was mediated by competition over resources. Using 105 lizards collected from three independent populations, we found that individual risk-taking behaviour was repeatable when measured in either social isolation or within groups both with and without food resources available. However, lizards that were bolder during individual trials were not also bolder when in groups, regardless of resource availability. This was largely driven by individual differences in social behavioural plasticity, whereby individual skinks responded differently to the presence of conspecifics. Together, this resulted in a rank order change of individual behavioural types across the social conditions. Our results highlight the importance of the social environment in mediating animal personality traits across varying levels of resource availability. Further, these findings suggest that behavioural traits when measured in isolation, may not reflect individual variation in behaviour when measured in more ecologically realistic social groups

Prevalence of Lower Urinary Tract Symptoms in China, Taiwan, and South Korea: Results from a Cross-Sectional, Population-Based Study.

INTRODUCTION: Few population-based data are available evaluating the prevalence of lower urinary tract symptoms (LUTS) in Asia. The objective of our study was to determine LUTS prevalence in China, Taiwan, and South Korea using International Continence Society (ICS) 2002 criteria. METHODS: An Internet-based self-administered survey among individuals aged at least 40 years with the ability to use a computer and to read the local language. Survey questions included ICS symptom definitions and the international prostate symptom score (IPSS). Data analysis was based on descriptive statistics and post hoc significance testing. RESULTS: There were 8284 participants, of whom 51% were women and 34% were aged at least 60 years. LUTS prevalence was slightly higher in men than women (62.8% vs. 59.6%; p = 0.004), increasing significantly with age (p = 0.001). All three ICS symptom groups (voiding, storage, and post-micturition) were present in 35% of individuals with LUTS. Symptoms with the highest overall prevalence were nocturia, frequency, incomplete emptying, and terminal dribble. The most bothersome symptoms were terminal dribble, nocturia, and urgency. According to IPSS scores, 87% of participants had at least mild symptoms; 43% of those aged over 60 years had moderate/severe symptoms. The percentage of participants with any LUTS who had visited healthcare professionals because of urinary symptoms was 26%, rising to 45% amongst individuals with all three symptom groups (p = 0.001 vs. other ICS symptom groups). CONCLUSIONS: LUTS are highly prevalent in men and women aged at least 40 years who participated in this study in China, Taiwan, and South Korea and increases with increasing age. A minority of individuals with LUTS seek healthcare and our results suggest an increased patient awareness of LUTS is required. FUNDING: Astellas Pharma Singapore Pte. Ltd. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT02618421

The Ministry of Works and the Development of Souvenir Guides from 1955

The first formal guidebooks for historic sites placed in state guardianship in the United Kingdom appeared in 1917. There was an expansion of the series in the 1930s and 1950s. However, from the late 1950s the Ministry of Works, and later the Ministry of Public Buildings and Works, started to produce an additional series of illustrated souvenir guides. One distinct group covered Royal Palaces: the Tower of London, Hampton Court Palace, Queen Victoria's residence of Osborne House on the Isle of Wight, and Holyroodhouse in Edin-burgh. This was followed by guides for archaeological sites such as Stone-henge and Avebury, the Neolithic flint mines at Grime's Graves, the Roman villa at Lullingstone, and Hadrian's Wall. In 1961, a series of guides, with covers designed by Kyffin Williams, was produced for the English castles constructed in North Wales. These illustrated guides, some with colour, prepared the way for the fully designed guides now produced by English Heritage, Cadw, and Historic Environment Scotland