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Many systems and services rely on timing assumptions for performance and availability to perform critical aspects of their operation, such as various timeouts for failure detectors or optimizations to concurrency control mechanisms. Many such assumptions rely on the ability of different components to communicate on time -- a delay in communication may trigger the failure detector or cause the system to enter a less-optimized execution mode. Unfortunately, these timing assumptions are often set with little regard to actual communication guarantees of the underlying infrastructure -- in particular, the variability of communication delays between processes in different nodes/servers. The higher communication variability holds especially true for systems deployed in the public cloud since the cloud is a utility shared by many users and organizations, making it prone to higher performance variance due to noisy neighbor syndrome. In this work, we present Cloud Latency Tester (CLT), a simple tool that can help measure the variability of communication delays between nodes to help engineers set proper values for their timing assumptions. We also provide our observational analysis of running CLT in three major cloud providers and share the lessons we learned.

Purpose: Chronic pain is common in adolescents. Evidence-based guidelines recommend interdisciplinary treatment, but access is limited by geography. The development of hybrid programs utilizing both face-to-face and videoconference treatment may help overcome this. We developed a 7-week hybrid pediatric interdisciplinary pain program (Hybrid-PIPP) and wished to compare it to individual face-to-face sessions (Standard Care). Our objective was to test the feasibility of a protocol that used a matched pair un-blinded randomized controlled design to investigate the efficacy and cost-effectiveness of the Hybrid-PIPP compared to Standard Care. Patients and Methods: Parent–adolescent dyads were recruited from tertiary pediatric clinics and matched by disability before randomization to minimize allocation bias. The adolescents (aged 11– 17) had experienced primary pain for > 3 months. Hybrid-PIPP involved 11 hrs of group therapy and 4 individual videoconference sessions. Standard care was provided by the same clinical team, using the same treatment model and similar intensity as the Hybrid-PIPP. The intention was to recruit participants for 3 Hybrid-PIPP groups with a comparison stream. Recruitment was ceased after 2 groups due to the high participant disability requiring more intensive intervention. Results: Eighteen dyads were screened and 13 randomized (7 Hybrid-PIPP, 6 Standard Care, 2 unsuitable, 3 unallocated when the study was stopped). The study met a priori feasibility criteria for staff availability; recruitment rate; treatment completion; and data collection. Global satisfaction ratings were similar in both streams (SC median 7, range 5– 9 and Hybrid-PIPP median 8.5, range 5– 10). Challenges were identified in both streams. A future modified Hybrid-PIPP was considered acceptable if the intensity is increased to manage the high level of disability. Standard care was considered inefficient. No adverse events were reported. Conclusion: The study determined that the

Purpose: Chronic pain is common in adolescents. Evidence-based guidelines recommend interdisciplinary treatment, but access is limited by geography. The development of hybrid programs utilizing both face-to-face and videoconference treatment may help overcome this. We developed a 7-week hybrid pediatric interdisciplinary pain program (Hybrid-PIPP) and wished to compare it to individual face-to-face sessions (Standard Care). Our objective was to test the feasibility of a protocol that used a matched pair un-blinded randomized controlled design to investigate the efficacy and cost-effectiveness of the Hybrid-PIPP compared to Standard Care. Patients and Methods: Parent–adolescent dyads were recruited from tertiary pediatric clinics and matched by disability before randomization to minimize allocation bias. The adolescents (aged 11– 17) had experienced primary pain for > 3 months. Hybrid-PIPP involved 11 hrs of group therapy and 4 individual videoconference sessions. Standard care was provided by the same clinical team, using the same treatment model and similar intensity as the Hybrid-PIPP. The intention was to recruit participants for 3 Hybrid-PIPP groups with a comparison stream. Recruitment was ceased after 2 groups due to the high participant disability requiring more intensive intervention. Results: Eighteen dyads were screened and 13 randomized (7 Hybrid-PIPP, 6 Standard Care, 2 unsuitable, 3 unallocated when the study was stopped). The study met a priori feasibility criteria for staff availability; recruitment rate; treatment completion; and data collection. Global satisfaction ratings were similar in both streams (SC median 7, range 5– 9 and Hybrid-PIPP median 8.5, range 5– 10). Challenges were identified in both streams. A future modified Hybrid-PIPP was considered acceptable if the intensity is increased to manage the high level of disability. Standard care was considered inefficient. No adverse events were reported. Conclusion: The study determined that the

Anna Hilyard,1,2 Julia Kingsley,1 David Sommerfield,1,3,4 Susan Taylor,1,5 Natasha Bear,6 Noula Gibson7,8 1Complex Pain Service, Perth Children’s Hospital, Perth, Western Australia, Australia; 2Discipline of Psychology, College of Science, Health, Engineering and Education, Murdoch University, Perth, Western Australia, Australia; 3Department of Anaesthesia and Pain Management, Perth Children’s Hospital, Perth, Australia; 4Medical School, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, Australia; 5School of Occupational Therapy, Social Work and Speech Pathology, Faculty of Health Sciences, Curtin University, Perth, Western Australia, Australia; 6Department of Child Research, Child Adolescent Health Service, Perth, Western Australia, Australia; 7Physiotherapy Department, Perth Children’s Hospital, Perth, Western Australia, Australia; 8School of Physiotherapy and Exercise Science, Faculty of Health Sciences, Curtin University, Perth, Western Australia, AustraliaCorrespondence: Anna HilyardComplex Pain Service, Perth Children’s Hospital, Locked Bag 2010, Nedlands, Western Australia 6909, AustraliaTel +6186456 4341Email anna.hilyard@health.wa.gov.auPurpose: Chronic pain is common in adolescents. Evidence-based guidelines recommend interdisciplinary treatment, but access is limited by geography. The development of hybrid programs utilizing both face-to-face and videoconference treatment may help overcome this. We developed a 7-week hybrid pediatric interdisciplinary pain program (Hybrid-PIPP) and wished to compare it to individual face-to-face sessions (Standard Care). Our objective was to test the feasibility of a protocol that used a matched pair un-blinded randomized controlled design to investigate the efficacy and cost-effectiveness of the Hybrid-PIPP compared to Standard Care.Patients and Methods: Parent–adolescent dyads were recruited from tertiary pediatric clinics and matched by

We report on the design and performance of the Keck Cosmic Web Imager (KCWI), a general purpose optical integral field spectrograph that has been installed at the Nasmyth port of the 10 m Keck II telescope on Mauna Kea, HI. The novel design provides blue-optimized seeing-limited imaging from 350-560 nm with configurable spectral resolution from 1000 - 20000 in a field of view up to 20"x33". Selectable volume phase holographic (VPH) gratings and high performance dielectric, multilayer silver and enhanced aluminum coatings provide end-to-end peak efficiency in excess of 45% while accommodating the future addition of a red channel that will extend wavelength coverage to 1 micron. KCWI takes full advantage of the excellent seeing and dark sky above Mauna Kea with an available nod-and-shuffle observing mode. The instrument is optimized for observations of faint, diffuse objects such as the intergalactic medium or cosmic web. In this paper, a detailed description of the instrument design is provided with measured performance results from the laboratory test program and ten nights of on-sky commissioning during the spring of 2017. The KCWI team is lead by Caltech and JPL (project management, design and implementation) in partnership with the University of California at Santa Cruz (camera optical and mechanical design) and the W. M. Keck Observatory (observatory interfaces)., Comment: 33 pages, 31 figures. Accepted to the Astrophysical Journal

We report on the design and performance of the Keck Cosmic Web Imager (KCWI), a general purpose optical integral field spectrograph that has been installed at the Nasmyth port of the 10 m Keck II telescope on Mauna Kea, HI. The novel design provides blue-optimized seeing-limited imaging from 350-560 nm with configurable spectral resolution from 1000 - 20000 in a field of view up to 20"x33". Selectable volume phase holographic (VPH) gratings and high performance dielectric, multilayer silver and enhanced aluminum coatings provide end-to-end peak efficiency in excess of 45% while accommodating the future addition of a red channel that will extend wavelength coverage to 1 micron. KCWI takes full advantage of the excellent seeing and dark sky above Mauna Kea with an available nod-and-shuffle observing mode. The instrument is optimized for observations of faint, diffuse objects such as the intergalactic medium or cosmic web. In this paper, a detailed description of the instrument design is provided with measured performance results from the laboratory test program and ten nights of on-sky commissioning during the spring of 2017. The KCWI team is lead by Caltech and JPL (project management, design and implementation) in partnership with the University of California at Santa Cruz (camera optical and mechanical design) and the W. M. Keck Observatory (observatory interfaces)., Comment: 33 pages, 31 figures. Accepted to the Astrophysical Journal

The Automated Planet Finder (APF) is a facility purpose-built for the discovery and characterization of extrasolar planets through high-cadence Doppler velocimetry of the reflex barycentric accelerations of their host stars. Located atop Mt. Hamilton, the APF facility consists of a 2.4-m telescope and its Levy spectrometer, an optical echelle spectrometer optimized for precision Doppler velocimetry. APF features a fixed format spectral range from 374 nm - 970 nm, and delivers a "Throughput" (resolution * slit width product) of 114,000 arc-seconds, with spectral resolutions up to 150,000. Overall system efficiency (fraction of photons incident on the primary mirror that are detected by the science CCD) on blaze at 560 nm in planet-hunting mode is 15%. First-light tests on the RV standard stars HD 185144 and HD 9407 demonstrate sub-meter per second precision (RMS per observation) held over a 3-month period. This paper reviews the basic features of the telescope, dome, and spectrometer, and gives a brief summary of first-light performance., Comment: Accepted at PASP. Version with full resolution available at http://oklo.org/Vogt_APF_2014.pdf

The Automated Planet Finder (APF) is a facility purpose-built for the discovery and characterization of extrasolar planets through high-cadence Doppler velocimetry of the reflex barycentric accelerations of their host stars. Located atop Mt. Hamilton, the APF facility consists of a 2.4-m telescope and its Levy spectrometer, an optical echelle spectrometer optimized for precision Doppler velocimetry. APF features a fixed format spectral range from 374 nm - 970 nm, and delivers a "Throughput" (resolution * slit width product) of 114,000 arc-seconds, with spectral resolutions up to 150,000. Overall system efficiency (fraction of photons incident on the primary mirror that are detected by the science CCD) on blaze at 560 nm in planet-hunting mode is 15%. First-light tests on the RV standard stars HD 185144 and HD 9407 demonstrate sub-meter per second precision (RMS per observation) held over a 3-month period. This paper reviews the basic features of the telescope, dome, and spectrometer, and gives a brief summary of first-light performance., Comment: Accepted at PASP. Version with full resolution available at http://oklo.org/Vogt_APF_2014.pdf

The objective of this study was to evaluate the factor structure, validity, and reliability of the Compulsive Exercise Test (CET) in an adolescent clinical eating disorder population. The data source was the Helping to Outline Paediatric Eating Disorders (HOPE) Project, a prospective ongoing registry study comprising consecutive pediatric tertiary eating disorder referrals. Adolescents (N=104; 12–17 years) with eating disorders completed the CET and other measures. Factor structure, convergent validity, and internal consistency were evaluated. Despite failing to identify a factor structure, the study provided clear evidence of the multidimensionality of the measure. The total score correlated significantly with measures of eating pathology, perfectionism, and frequency of exercise for shape and weight control (r = 0.32–0.70, ps < 0.05). More research into the multidimensional nature of compulsive exercise in clinical populations is needed. Further, research into compulsive exercise offers promise as an addition to existing cognitive behavioral models and treatments for eating disorders.

Let $w$ be a word in alphabet $\{x,D\}$ with $m$ $x$'s and $n$ $D$'s. Interpreting "$x$" as multiplication by $x$, and "$D$" as differentiation with respect to $x$, the identity $wf(x) = x^{m-n}\sum_k S_w(k) x^k D^k f(x)$, valid for any smooth function $f(x)$, defines a sequence $(S_w(k))_k$, the terms of which we refer to as the {\em Stirling numbers (of the second kind)} of $w$. The nomenclature comes from the fact that when $w=(xD)^n$, we have $S_w(k)={n \brace k}$, the ordinary Stirling number of the second kind. Explicit expressions for, and identities satisfied by, the $S_w(k)$ have been obtained by numerous authors, and combinatorial interpretations have been presented. Here we provide a new combinatorial interpretation that retains the spirit of the familiar interpretation of ${n \brace k}$ as a count of partitions. Specifically, we associate to each $w$ a quasi-threshold graph $G_w$, and we show that $S_w(k)$ enumerates partitions of the vertex set of $G_w$ into classes that do not span an edge of $G_w$. We also discuss some relatives of, and consequences of, our interpretation, including $q$-analogs and bijections between families of labelled forests and sets of restricted partitions., Comment: To appear in Eur. J. Combin., doi:10.1016/j.ejc.2014.07.002

Background: During the 2009 H1N1 pandemic, the global health community sought to make vaccine available "in developing nations in the same timeframe as developed nations." However, richer nations placed advance orders with manufacturers, leaving poorer nations dependent on the quantity and timing of vaccine donations by manufacturers and rich nations. Knowledge of public support for timely donations could be important to policy makers during the next pandemic. We explored what the United States (US) public believes about vaccine donation by its country to poorer countries. Methods and Findings: We surveyed 2079 US adults between January 22 nd and February 1 st 2010 about their beliefs regarding vaccine donation to poorer countries. Income (p = 0.014), objective priority status (p = 0.005), nativity, party affiliation, and political ideology (p<0.001) were significantly related to views on the amount of vaccine to be donated. Though party affiliation and political ideology were related to willingness to donate vaccine (p<0.001), there was bipartisan support for timely donations of 10% of the US vaccine supply so that those "at risk in poorer countries can get the vaccine at the same time" as those at risk in the US. Conclusions: We suggest that the US and other developed nations would do well to bolster support with education and public discussion on this issue prior to an emerging pandemic when emotional reactions could potentially influence support for donation. We conclude that given our evidence for bipartisan support for timely donations, it may be necessary to design multiple arguments, from utilitarian to moral, to strengthen public and policy makers' support for donations. © 2012 Kumar et al.

Background: During the 2009 H1N1 pandemic, the global health community sought to make vaccine available "in developing nations in the same timeframe as developed nations." However, richer nations placed advance orders with manufacturers, leaving poorer nations dependent on the quantity and timing of vaccine donations by manufacturers and rich nations. Knowledge of public support for timely donations could be important to policy makers during the next pandemic. We explored what the United States (US) public believes about vaccine donation by its country to poorer countries. Methods and Findings: We surveyed 2079 US adults between January 22 nd and February 1 st 2010 about their beliefs regarding vaccine donation to poorer countries. Income (p = 0.014), objective priority status (p = 0.005), nativity, party affiliation, and political ideology (p<0.001) were significantly related to views on the amount of vaccine to be donated. Though party affiliation and political ideology were related to willingness to donate vaccine (p<0.001), there was bipartisan support for timely donations of 10% of the US vaccine supply so that those "at risk in poorer countries can get the vaccine at the same time" as those at risk in the US. Conclusions: We suggest that the US and other developed nations would do well to bolster support with education and public discussion on this issue prior to an emerging pandemic when emotional reactions could potentially influence support for donation. We conclude that given our evidence for bipartisan support for timely donations, it may be necessary to design multiple arguments, from utilitarian to moral, to strengthen public and policy makers' support for donations. © 2012 Kumar et al.

The DEIMOS spectrograph is a multi-object spectrograph being built for Keck II. DEIMOS was delivered in February 2002, became operational in May, and is now about three-quarters of the way through its commissioning period. This paper describes the major problems encountered in completing the spectrograph, with particular emphasis on optical quality and image motion. The strategies developed to deal with these problems are described. Overall, commissioning is going well, and it appears that DEIMOS will meet all of its major performance goals.

The DEIMOS spectrograph is a multi-object spectrograph being built for Keck II. DEIMOS was delivered in February 2002, became operational in May, and is now about three-quarters of the way through its commissioning period. This paper describes the major problems encountered in completing the spectrograph, with particular emphasis on optical quality and image motion. The strategies developed to deal with these problems are described. Overall, commissioning is going well, and it appears that DEIMOS will meet all of its major performance goals.

1:100 000 geological mapping of Bougainville Island has resulted in refinement of stratigraphic subdivisions and relationships. The Kupei Complex, host to the Panguna porphyry copper-gold deposit, consists of medium-K2O microdiorites, granodiorites, and andesites intruding Arawa Conglomerate and Toniva Formation. The Panguna Andesite may be a composite unit of intrusive microdiorite and Arawa Conglomerate, perhaps containing extrusive andesite., 1:100 000 geological mapping of Bougainville Island has resulted in refinement of stratigraphic subdivisions and relationships. The Kupei Complex, host to the Panguna porphyry copper-gold deposit, consists of medium-K2O microdiorites, granodiorites, and andesites intruding Arawa Conglomerate and Toniva Formation. The Panguna Andesite may be a composite unit of intrusive microdiorite and Arawa Conglomerate, perhaps containing extrusive andesite.

An apparatus has been developed for the measurement of the dynamic mechanical properties of foamed materials impregnated with viscous fluids over a wide frequency and temperature range. Preliminary results are given for two foams. Measurements of rolling friction on foam-fluid substrates have also been obtained in two ways for a number of low-density foams. They are compared with the predictions of a simple theoretical treatment of rolling friction on viscoelastic substrates. An analysis is given of the distributions of stress and displacement in solid rubber blocks subjected to small compressions between rigid frictional surfaces. Particular consideration is given to local sliding motions in the outer regions of the loaded surfaces, as a possible means of energy dissipation. Preliminary experimental measurements of the amount of sliding are reported. (Author)

Apparatus has been developed to measure the dynamic mechanical properties of foamed materials filled with a viscous fluid, over a frequency range from 0.002 to 200 Hz and a temperature range from -50 o C to +100 o C. Measurements have been made on various foam/ fluid systems including rubber latex, polyether and polyester foams filled with air, glycerin, silicone oil and water. The Gent-Rusch theory has been modified to take into account inertia effects, damping in the matrix material itself, and special features of the text-piece assembly . The theory is shown to describe the measurements successfully and verifies the engineering validity of the approach outline. (Author-PL)

An apparatus was developed to measure the dynamic mechanical properties of foamed materials filled with a viscous fluid, over a frequency range from 0.002 to 200 Hz. It has been tested using two model viscoelastic materials over the temperature range -50C to +100C. Measurements were then made on various foam/fluid systems including rubber latex, polyether and polyester foams filled with air, glycerin, silicone oil and water. The Gent-Rusch theory has been modified to take into account inertia effects, damping in the matrix material itself, and special features of the test-piece assembly. The modified theory is shown to describe the measurements successfully over the entire frequency range employed. Stress-optical coefficients have been determined for lightly-cross-linked samples of cis- and trans-polyisoprene, swollen to a high degree in a variety of non-polar solvents. A strong dependence on the geometrical asymmetry of the solvent molecule has been observed. Solvents with long straight molecules gave large values of the stress-optical coefficient whereas those with compact symmetrical molecules gave minimum values. This effect is attributed to short-range orientational order, due to packing effects in a molecularly-anisotropic medium. (Author)

The integrated engineering and service test of the Supplementary Light Source, AN/VSS-3 was changed to a six-month tropic storage test to be conducted from March until September in the Canal Zone. Objective was to determine if the criteria specified for storage of the item can be met in a humid tropic environment. Monthly microbiological examinations were made during the storage test. Each test item was activated for one hour before shipment. As the test items did not undergo a full 12-month storage period, no conclusions can be drawn. It was noted, however, that the search light and some of its components were susceptible to fungus, moisture, and corrosion after only six months of tropic storage. It is recommended that the test items be treated and sealed to increase moisture, corrosion, and fungus resistance, and then subjected to a full 12-month storage test in the humid tropic environment.

The internship experience with the Department of Community Development and its Urban Programs Division provided an opportunity to participate in the preparation and revision of operating budgets, in the organizing and revision of fiscal management systems and in the review and preparation of a federally assisted program. The functioning of intergovernmental relations was observed both between the city and the national government and between the city and the state government. Also, the role of individual personalities was observed in such relations. A part of the first two weeks of the internship was spent in private meetings with various department directors and division administrators. In these meetings, particular attention was paid to the techniques the directors and administrators use in the budgetary process. When the internship was over, the practical experience which it provided was compared to the academic experience.

The internship experience with the Department of Community Development and its Urban Programs Division provided an opportunity to participate in the preparation and revision of operating budgets, in the organizing and revision of fiscal management systems and in the review and preparation of a federally assisted program. The functioning of intergovernmental relations was observed both between the city and the national government and between the city and the state government. Also, the role of individual personalities was observed in such relations. A part of the first two weeks of the internship was spent in private meetings with various department directors and division administrators. In these meetings, particular attention was paid to the techniques the directors and administrators use in the budgetary process. When the internship was over, the practical experience which it provided was compared to the academic experience.

Interpretation of new Discovery 2000 aeromagnetic data has allowed the definition of magnetic domains which correlate well with outcrop geology in the southern part of this area of New South Wales and permit extrapolation along strike to the north. Some of the interpretations have been tested by drilling. Economically important units such as the Ordovician volcanics and ultramafics and the Cambro-Ordovician mafic schists have been mapped under the Mesozoic-Cainozoic cover to the north, as well as the Silurian Nyngan intrusive complex and the Devonian Yeovil batholith. Other features identified include north-striking synclines, the Parkes thrust and the Nyngan transverse zone. Potential for precious and base metal mineralisation, in varying styles, exists in a number of different units that extend under the cover., Interpretation of new Discovery 2000 aeromagnetic data has allowed the definition of magnetic domains which correlate well with outcrop geology in the southern part of this area of New South Wales and permit extrapolation along strike to the north. Some of the interpretations have been tested by drilling. Economically important units such as the Ordovician volcanics and ultramafics and the Cambro-Ordovician mafic schists have been mapped under the Mesozoic-Cainozoic cover to the north, as well as the Silurian Nyngan intrusive complex and the Devonian Yeovil batholith. Other features identified include north-striking synclines, the Parkes thrust and the Nyngan transverse zone. Potential for precious and base metal mineralisation, in varying styles, exists in a number of different units that extend under the cover.

One school of thought based on the current boom in the aluminium industry anticipates its continued growth at about 1-2% into the next decade. An alternative view, argues that the industry is entering a period of zero growth. These analysts predict falling prices and permanent closure of high cost capacity in the 1990s. The author favours this argument and suggests some implications that will ensue., One school of thought based on the current boom in the aluminium industry anticipates its continued growth at about 1-2% into the next decade. An alternative view, argues that the industry is entering a period of zero growth. These analysts predict falling prices and permanent closure of high cost capacity in the 1990s. The author favours this argument and suggests some implications that will ensue.

This report is prefaced by a brief review of factors in the international economic environment which will influence the aluminium market. These factors include changes in the situation and outlook for world industrial production growth in the light of the stock market fallout, changes in oil prices and in currency alignments. It deals with the state of the market for bauxite, alumina and aluminium and briefly outlines the short term outlook in each of those markets., This report is prefaced by a brief review of factors in the international economic environment which will influence the aluminium market. These factors include changes in the situation and outlook for world industrial production growth in the light of the stock market fallout, changes in oil prices and in currency alignments. It deals with the state of the market for bauxite, alumina and aluminium and briefly outlines the short term outlook in each of those markets.