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Wet markets have been implicated in multiple zoonotic outbreaks, including COVID-19. They are also a conduit for legal and illegal trade in wildlife, which threatens thousands of species. Yet wet markets supply food to millions of people around the world, and differ drastically in their physical composition, the goods they sell, and the subsequent risks they pose. As such, policy makers need to know how to target their actions to efficiently safeguard human health and biodiversity without depriving people of ready access to food. Here, we propose a taxonomy of wet markets, oriented around the presence of live or dead animals, and whether those animals are domesticated or wild (either captive-reared or wild-caught). We assess the dimensions and levels of risk that different types of wet markets pose to people and to biodiversity. We identify six key risk factors of wet markets that can affect human health: (1) presence of high disease-risk animal taxa, (2) presence of live animals, (3) hygiene conditions, (4) market size, (5) animal density and interspecies mixing, and (6) the length and breadth of animal supply chains. We also identify key factors informing risk to biodiversity. Finally, we recommend targeted, risk-adjusted policies to more efficiently and humanely address the dangers posed by wet markets.

Low-density polyethylene (LDPE) is a commodity polymer widely used in a variety of applications. Due to the complexity of its molecular structure, which includes molecular weight distribution and randomly distributed long-chain branching, its rheological behavior is varied. In the present work, a mathematical model is used to predict molecular and rheological properties of LDPE produced in a high-pressure tubular reactor under different operating conditions. The agreement between flow curve predictions and experimental data is very good, demonstrating the potential of this model as a predictive tool for industrial producers.

The first combustion experiments aboard the Japanese Experiment Module “Kibo” on the International Space Station, titled “Elucidation of Flame Spread and Group Combustion Excitation Mechanism of Randomly Distributed Droplet Clouds (Group Combustion)” were conducted in 2017 in order to bridge the gap between droplet combustion and spray combustion through flame spread over droplet arrays, droplet-cloud elements and randomly distributed droplet clouds. n-Decane droplets were distributed randomly on a SiC-fiber lattice, and the flame spread and group-combustion excitation were observed. During the flame spread near the group-combustion-excitation limit, two types of anomalous behavior appeared: large-scale ignition and re-burning by a slow flame propagation in a burned area. We successfully simulated similar phenomena by a flame-spread experiment using droplet-cluster arrays. The large-scale ignition phenomenon is caused by the ignition of a flammable mixture generated by heating multiple droplets existing outside the local flame-spread limit. The re-burning phenomenon by the slow flame propagation in a burned area is caused by the ignition of a flammable mixture diluted by the combustion products after the radiative extinction of the group flame. There is the possibility of a cool-flame appearance in both phenomena.

BACKGROUND: The current neuroblastoma (NBL) staging system employs image-defined risk factors (IDRFs) to assess numerous anatomic features, but the impact of IDRFs on surgical and oncologic outcomes is unclear. METHODS: The Vanderbilt Cancer Registry identified children treated for NBL from 2002 to 2017. Tumor volume (TV) and IDRFs were measured radiographically at diagnosis and before resection. Perioperative and oncologic outcomes were evaluated. RESULTS: At diagnosis of 106 NBL, 61% were IDRF positive. MYCN-amplified and undifferentiated NBL had more IDRFs than nonamplified and more differentiated tumors (p = 0.001 and p = 0.01). Of 86 NBLs resected, 43% were IDRF positive, which associated with higher stage, risk, and TV (each p < 0.001). The presence of IDRF at resection was also associated with increased blood loss (p < 0.001), longer operating times (p < 0.001), greater incidence of intraoperative complications (p = 0.03), more frequent ICU admissions postoperatively (p < 0.001), and longer hospital stays (p < 0.001). IDRF negative and positive tumors did not have significantly different rates of gross total resection (p = 0.2). Five-year relapse-free and overall survival was similar for IDRF negative and positive NBL (p = 0.9 and p = 0.8). CONCLUSIONS: IDRFs at diagnosis were associated with larger, less differentiated, advanced stage, and higher risk NBL and at resection with increased operative difficulty and perioperative morbidity. However, the frequency of gross total resection and patient survival after resection were not associated with the presence of IDRFs. TYPE OF STUDY: Retrospective cohort study. LEVEL OF EVIDENCE: Level III.

Transient, isolated n-alkane droplet combustion is simulated at elevated pressure for helium-diluent substituted-air mixtures. We report the presence of unique quasi-steady, three-stage burning behavior of large sphero-symmetric n-alkane droplets at these elevated pressures and helium substituted ambient fractions. Upon initiation of reaction, hot-flame diffusive burning of large droplets is initiated that radiatively extinguishes to establish cool flame burning conditions in nitrogen/oxygen “air” at atmospheric and elevated pressures. However, at elevated pressure and moderate helium substitution for nitrogen (XHe > 20%), the initiated cool flame burning proceeds through two distinct, quasi-steady-state, cool flame burning conditions. The classical “Hot flame” (∼1500 K) radiatively extinguishes into a “Warm flame” burning mode at a moderate maximum reaction zone temperature (∼ 970 K), followed by a transition to a lower temperature (∼765 K), quasi-steady “Cool flame” burning condition. The reaction zone (“flame”) temperatures are associated with distinctly different yields in intermediate reaction products within the reaction zones and surrounding near-field, and the flame-standoff ratios characterizing each burning mode progressively decrease. The presence of all three stages first appears with helium substitution near 20%, and the duration of each stage is observed to be strongly dependent on helium substitutions level between 20–60%. For helium substitution greater than 60%, the hot flame extinction is followed by only the lower temperature cool flame burning mode. In addition to the strong coupling between the diffusive loss of both energy and species and the slowly evolving degenerate branching in the low and negative temperature coefficient (NTC) kinetic regimes, the competition between the low-temperature chain branching and intermediate-temperature chain termination reactions control the “Warm” and “Cool” flame quasi-steady conditions and transitioning dynamics. Experiments onboard the International Space Station with n-dodecane droplets confirm the existence of these combustion characteristics and predictions agree favorably with these observations.

Droplet-combustion experiments with normal-alkane fuels, carried out onboard the International Space Station, have shown that, after radiative extinction of a droplet burning with an ordinary hot flame, often quasi-steady burning is initiated and sustained by a chemical-kinetic mechanism associated with cool flames. This second, cool-flame combustion stage occurs in a partial-burning regime in which both fuel and oxygen leak through a reaction zone that is controlled by the low-temperature chemistry of cool flames. This second stage persists for an appreciable period of time, after which it is terminated by cool-flame extinction, often at a measurable non-zero droplet diameter. This extinction diameter depends on the fuel and on the composition of the ambient atmosphere. Experiments involving large fuel droplets of different initial diameters indicate that the value of this cool-flame extinction diameter may vary with the initial droplet diameter and with the ignition energy imparted by the hot-wire igniters, even though the cool flame lies well within the region described as the inner quasi-steady zone, where flame structures are independent of initial conditions. These observations imply that the effective ambient atmosphere during the second stage likely depends on the previous combustion history. In the present contribution, evaluations are reported concerning possible influences of the ignition process, of the first-stage hot-flame combustion, and of prior cool-flame combustion on the effective atmosphere in which the second-stage combustion and extinction occur. It is concluded that analysis of influences of fuel leakage and condensation may be needed.

Millimeter-size fuel droplets burning in microgravity show substantial thermal expansion at earlier times in their burning history. Here, we develop a simple model that accounts for thermal expansion of the liquid fuel and compare it against experimental measurements. The results show that excellent agreement with measured droplet-diameter histories throughout the hot-flame period of combustion is obtained when the effect of thermal expansion is included.

Experimental observations are presented concerning radiative extinction of large n-alkane droplets in diluent-substituted environments at moderately varied pressures in microgravity onboard the International Space Station. The fuels considered are n-heptane, n-octane, and n-decane with carbon dioxide, helium, and xenon used as inerts, replacing nitrogen as diluents at varying amounts. It is shown that a simple scaling analysis, based on the assumptions that radiative extinction occurs when the flame temperature drops to a critical value and that the radiative heat loss rate is a fraction of the heat-release rate at the flame, is able to correlate the measured droplet diameter at extinction as a function of its initial diameter and of the ambient gas-mixture properties.

BACKGROUND: Embryonal tumors arise typically in infants and young children and are often massive at presentation. Operative resection is a cornerstone in the multimodal treatment of embryonal tumors but potentially disrupts therapeutic timelines. When used appropriately, minimally invasive surgery can minimize treatment delays. The oncologic integrity and safety attainable with minimally invasive resection of embryonal tumors, however, remains controversial. METHODS: Query of the Vanderbilt Cancer Registry identified all children treated for intracavitary, embryonal tumors during a 15-year period. Tumors were assessed radiographically to measure volume (mL) and image-defined risk factors (neuroblastic tumors only) at time of diagnosis, and at preresection and postresection. Patient and tumor characteristics, perioperative details, and oncologic outcomes were compared between minimally invasive surgery and open resection of tumors of comparable size. RESULTS: A total of 202 patients were treated for 206 intracavitary embryonal tumors, of which 178 were resected either open (n = 152, 85%) or with minimally invasive surgery (n = 26, 15%). The 5-year, relapse-free, and overall survival were not significantly different after minimally invasive surgery or open resection of tumors having a volume less than 100 mL, corresponding to the largest resected with minimally invasive surgery (P = .249 and P = .124, respectively). No difference in margin status or lymph node sampling between the 2 operative approaches was detected (p = .333 and p = .070, respectively). Advantages associated with minimally invasive surgery were decreased blood loss (P < .001), decreased operating time (P = .002), and shorter hospital stay (P < .001). Characteristically, minimally invasive surgery was used for smaller volume and earlier stage neuroblastic tumors without image-defined risk factors. CONCLUSION: When selected appropriately, minimally invasive resection of pediatric embryonal tumors, particularly neuroblastic tumors, provides acceptable oncologic integrity. Large tumor volume, small patient size, and image-defined risk factors may limit the broader applicability of minimally invasive surgery.

Droplet combustion experiments carried out in the International Space Station using n-alkane fuels have shown that large droplets, when ignited, first burn with visible hot flames and then extinguish, only to be followed later by quasi-steady cool-flame combustion. In a few of these experiments, some of the nitrogen in the nitrogen-oxygen ambient-gas mixture was replaced by helium, carbon dioxide, or xenon, for n-heptane, n-octane, n-decane, or n-dodecane droplets. Different diluents were observed to exert remarkably different influences on the cool-flame combustion. These initially unexpected differences are summarized here, with explanations offered for their causes. In particular, a simplified theoretical description of cool-flame-supported droplet combustion is employed to predict burning-rate constants and droplet diameters at cool-flame extinction, resulting in good agreement with much of the experimental data but disagreement with certain measurements, for reasons that are explained. The comparisons underscore the important influence of the diluent, especially on the Lewis numbers of cool-flame intermediate species derived from the fuel vapor.

Droplet combustion experiments carried out onboard the International Space Station, using pure fuels and fuel mixtures, have shown that quasi-steady burning can be sustained by a non-traditional flame configuration, namely a “cool flame” burning in the “partial-burning” regime where both fuel and oxygen leak through the low-temperature-controlled flame-sheet. Recent experiments involving large, bi-component fuel ( n -decane and hexanol, 50/50 by volume) droplets at elevated pressures show that the visible, hot flame becomes extremely weak while the burning rate remains relatively high, suggesting the possible simultaneous presence of “cool” and “hot” flames of roughly equal importance. The radiant output from these bi-component droplets is relatively high and cannot be accounted for only by the presence of a visible hot flame. In this analysis we explore the theoretical possibility of a dual-flame structure, where one flame lies close to the droplet surface, called the “cool flame”, and the other farther away from the droplet surface, termed the “hot flame”. A Burke-Schumann analysis of this dual structure seems to indicate that such flame structures are possible over a limited range of initial conditions. These theoretical results can be compared against available experimental data for pure and bi-component fuel droplet combustion to test how realistic the model may be.

Observations of “ Cool Flame ” burning for large diameter isolated droplets on board the International Space Station have stimulated interest in combustion initiation/generation of non-premixed combustion modes. For a number of n -alkane fuels at large initial droplet diameters, the initiation process was observed to first establish a hot flame condition that radiatively extinguished, followed by a quasi-steady, “ Cool Flame ” droplet burning mode. However, recent large diameter n -decane experiments show that depending on the ignition energy supplied, the first stage hot flame condition was absent, with an apparent, direct establishment of a “ Cool Flame ” burning mode that continued to diffusive extinction. Here we report these experimental observations and elucidate the underlying parameters resulting in dual and single stage “ Cool Flame ” burning. Detailed, transient sphero-symmetric droplet combustion modeling is applied to interpret the experiments. The simulations indicate that the balance and duration of the ignition energy applied, the energy release associated with reaction of partially premixed fuel vapor surrounding the droplet, heat flux to the drop surface, and far field diffusive heat loss all play key roles as to whether a dual stage, radiatively extinguished hot-flame-to- Cool - Flame -transition for only large droplets or direct establishment of “ Cool Flame ” burning for all droplet sizes occurs. The rate at which the reactive partially premixed vapor layer surrounding the droplet is formed, its volume, and its subsequent reaction significantly influence the observed transition to “ Cool Flame ” burning. The initial droplet temperature relative to saturation and flash point temperatures of the fuel and the liquid phase heat capacity contribute to the thermal transport requirement at the droplet surface for establishing the partially premixed reactive layer surrounding the droplet, which through its reaction history defines whether a transition to “ Cool Flame ” burning can be initiated without a requirement for radiative extinction of a hot flame burning mode.

Differential triangular flow, v 3 ( p T ) , of negative pions is measured at s NN = 17.3 GeV around midrapidity by the CERES/NA45 experiment at CERN in central PbAu collisions in the range 0–30% with a mean centrality of 5.5%. This is the first measurement as a function of transverse momentum of the triangular flow at SPS energies. The p T range extends from about 0.05 GeV/ c to more than 2 GeV/ c . The triangular flow magnitude, corrected for the HBT effects, is smaller by a factor of about 2 than the one measured by the PHENIX experiment at RHIC and the ALICE experiment at the LHC. Within the analyzed range of central collisions no significant centrality dependence is observed. The data are found to be well described by a viscous hydrodynamic calculation combined with an UrQMD cascade model for the late stages.

A recent set of experiments carried out onboard the International Space Station (ISS) have shown that large n-alkane droplets, after the radiative extinction of the visible flame, can burn quasi-steadily in a low-temperature regime, up to a diffusive extinction accompanied by the formation of a vapor cloud. The experiments have also demonstrated that small droplets are unable to exhibit radiative extinction, but instead burn to completion or disruptively extinguish. In this work, we applied a mathematical model able to reproduce the experimental data in terms of vaporization rates, standoff ratios, extinction diameters. A detailed kinetic mechanism (with ∼450 species and ∼17,000 reactions) was taken into account, in order to correctly reproduce the low-temperature combustion regime. The role of several parameters (initial diameter of the droplet, composition of the gaseous environment, and pressure) on the extinction of the hot-temperature flames was numerically investigated. Predictions are found in good agreement with experimental measurements, showing that only droplets with an initial diameter larger than a critical diameter undergo radiative extinction. A linear relationship between the squared critical diameter and the molar fraction of oxygen in the atmosphere was found and demonstrated on the basis of scaling arguments.

Background Estrogen receptor beta (ERβ) is expressed by 50% to 80% of triple-negative breast cancers (TNBC). Agonism of ERβ has antiproliferative effects in TNBC cells expressing ERβ. This phase 2 study evaluated single-agent high-dose estradiol in patients with advanced TNBC. Patients and Methods Adult women with measurable advanced TNBC were treated with estradiol 10 mg oral 3 times daily provided continuously for 28-day cycles. A Simon optimal 2-stage design was used. The primary end point was objective response (OR). Secondary end points included progression-free survival (PFS), clinical benefit (CB), and safety. OR, CB, and PFS by ERβ status were also examined. Results Seventeen evaluable women were enrolled. Median age was 58 years (range, 34-90 years); the median number of prior systemic therapies was 2 (range, 0-6). One patient had a confirmed partial response (OR rate, 5.9%) and remained on the study for > 24 weeks. Three patients had stable disease, with one lasting more than 16 weeks. ERβ expression was detected in 77% (13 patients). The CB rate at 16 weeks was 15% (2 of 13) in ERβ-positive patients and 0% (0 of 4) in ERβ-negative patients ( P = 1). PFS was poor (median, 1.9 months) and not statistically significantly different between ERβ-positive versus -negative patients. No new adverse events from estradiol were identified. The study closed after the first stage as a result of limited responses in these unselected patients. Conclusion In unselected TNBC, high-dose estradiol has limited efficacy. However, further evaluation of ERβ selective agonists in TNBC selected by ERβ expression may be warranted.

Modern automobile and airplane structures made of sheet metals or composites require usage of thinner and stronger materials. On the other hand, manufacturers are trying to reduce production costs by shortening the fabrication processes and by application of computed simulation for forming operation. Therefore, it is necessary to better understand and more accurately investigate deformation behaviour of sheet alloys. Testing of flat specimens under compression and cyclic tension-compression within large deformation procures a lot of problems. One of them is the buckling phenomenon. A new version of the device mounted in a standard testing machine was developed and geometry of the specimen for validation of the device was proposed. Specimens of DP690 steel with nominal thickness equal to 1.6 mm were investigated at ambient temperature. Tension-compression cyclic tests within a strain range ± 0.04 were executed starting in tension direction. It is shown that the results are repeatable.

Recent droplet-combustion experiments onboard the International Space Station (ISS) have revealed that large n-alkane droplets, following radiative extinction of the visible flame, can continue to burn quasi-steadily in a low-temperature regime, characterized by negative-temperature-coefficient (NTC) chemistry. In this study we report experimental observations of n-heptane, n-octane, and n-decane droplets of varying initial size burning in oxygen/nitrogen, oxygen/nitrogen/carbon dioxide, and oxygen/nitrogen/helium environments at pressures from 0.5 to 1.0 atm, with oxygen concentrations from 14% to 25% by volume. These large n-alkane droplets exhibited radiative extinction of the hot flame, followed by quasi-steady low-temperature burning, which terminated with diffusive extinction accompanied by the formation of a vapor cloud, while small droplets did not exhibit radiative extinction but instead burned to completion or disruptively extinguished. Results for droplet burning rates in both the hot-flame and cool-flame regimes, as well as droplet extinction diameters at the end of each stage, are presented. The cool-flame extinction diameters for all three n-alkanes are shown to follow a similar trend as functions of the oxygen concentration, predicted here from a simplified theoretical model that is based on the reaction-rate parameters for the oxygen molecule addition to the alkyl radical and for ketohydroperoxide decomposition.

This paper presents a transient model of internal catalytic combustion suitable for isolated channels and monolith reactors. Due to time-scales in the problem, the model considers a quasi-steady gas phase with a transient solid. The gas is described by axially varying bulk temperature and species. The gas includes lateral diffusion via transfer coefficients and the specification of a gas-phase species concentration at the wall; axial diffusion is neglected. The solid phase is a thermally thin shell with axially varying temperature, surface species, and surface species concentrations. The solid includes axial heat conduction and external heat loss by convection and radiation. The combustion process utilizes detailed gas and surface reaction models. The gas-phase model becomes a system of stiff ordinary differential equations with respect to axial position; the upstream (inlet) boundary conditions are specified and the axially varying solid properties are parameters in integration. The solid phase discretizes into a system of stiff ordinary differential-algebraic equations with respect to time. The time evolution of the system comes from alternating integrations of the quasi-steady gas phase and transient solid. The model is compared to two experimental cases using CO fuel: (1) steady-state conversion in an isothermal platinum tube and (2) transient propagation of a catalytic reaction inside a small platinum tube and includes external tube temperature measurements. This work presents sensitivity studies on important parameters including internal transfer coefficients, catalytic surface site density, external heat-loss, and others. Under mass-transfer limited conditions, global transfer coefficients are adequate to predict fuel conversion. Near light-off, the model predictions improve for the first case after adjusting the surface kinetics such that the net rate of CO adsorption increases compared to O 2 . For the second case, predictions of transient propagation speeds are good for equivalence ratios near unity and greater but require adjustment of external heat loss or kinetics to match under lean conditions.

Adjuvant therapy for breast cancer can be improved by increasing dose density. We tested the feasibility of delivering dose-dense docetaxel-cyclophosphamide (TC) in a single-arm phase II trial of 42 patients via the Wisconsin Oncology Network. Treatment was safe, tolerable, and most patients completed therapy as plan- ned. Thus, this commonly used regimen can be delivered in 8 weeks. Introduction: Dose-dense therapies have had a major effect on reducing toxicity and improving outcomes in breast cancer. A combination of TC every 3 weeks has emerged as a common chemotherapy regimen used for treatment of node-negative or lower-risk node-positive breast cancer. We tested whether it is feasible to deliver TC on a dose- dense schedule, with therapy completed within 10 weeks. Patients and Methods: We enrolled women with early stage breast cancer on a single-arm phase II study of adjuvant dose-dense TC through a regional oncology network. All women completed primary surgery before accrual, and subsequent therapy with TC was deemed appropriate by the treating physician. Planned treatment was docetaxel 75 mg/m 2 plus cyclophosphamide 600 mg/m 2 every 2 weeks for 4 cycles with subcutaneous pegfilgrastim 6 mg administered 24 to 48 hours after the administration of each chemotherapy cycle. Results: Of 42 women enrolled, 41 were evaluable using prespecified criteria. Of these, 37 (90.2%) completed therapy within 10 weeks and 34 (83%) completed therapy at 8 weeks without dose modification. Rates of neuropathy were similar to that reported previously. The rate of neutropenic fever was low (2.5%). Rash and plantar-palmar erythrodythesia were common and reached grade 3 in 4 subjects (9.8%). Conclusion: Dose-dense TC is feasible with tolerability profiles similar to standard TC and a low likelihood of neutropenic fever. This study supports further clinical development of this 8-week adjuvant chemotherapy regimen.

Ecological restoration increases, but evaluation of restoration efforts is inadequate because reliable performance indicators are lacking. As plants are important actors in ecological restoration, we suggest that they be used as metres, i.e. phytometers, of restoration success. Phytometer plants are transplanted to different conditions to integrate measures of the prevailing conditions. We analysed 109 studies for the use of phytometers and especially their applicability to evaluate ecological restoration. Most studies employed single species and life-stages and focused on habitat conditions and environmental impacts. Most experiments were conducted on grasslands in moist temperate regions. Growth was the dominant response variable, in long-term studies often combined with reproductive output and plant survival. Only five studies specifically evaluated ecological restoration, implying that its potential is not yet realised. We found phytometers promising in evaluating restoration outcomes given that they are easy to measure, can provide rapid results, and serve as integrative indicators of environmental conditions with the ability of covering many aspects of plant life and ecosystem processes. To evaluate restoration success with high resolution and generality, we suggest a combination of different phytometer species, life-forms and life-stages, and experimental periods >1 year to reduce effects of transplantation and between-year variation and to account for time lags in ecological processes and changes after restoration.

Experimental observations of anomalous combustion of n-heptane droplets burning in microgravity are reported. Following ignition, a relatively large n-heptane droplet first undergoes radiative extinction, that is, the visible flame ceases to exist because of radiant energy loss. But the droplet continues to experience vigorous vaporization for an extended period according to a quasi-steady droplet-burning law, ending in a secondary extinction at a finite droplet diameter, after which a vapor cloud rapidly appears surrounding the droplet. We hypothesize that the second-stage vaporization is sustained by low-temperature, soot-free, “cool-flame” chemical heat release. Measured droplet burning rates and extinction diameters are used to extract an effective heat release, overall activation energy, and pre-exponential factor for this low-temperature chemistry, and the values of the resulting parameters are found to be closer to those of “cool-flame” overall reaction-rate parameters, found in the literature, than to corresponding hot-flame parameters.

Foxy or Methoxy Foxy (5-methoxy- N , N -di(iso)propyltryptamine hydrochloride; 5-MeO-DIPT) is rapidly gaining popularity among recreational users as a hallucinogenic “designer drug.” Unfortunately, much remain unknown about the consequences of its use on neuropsychological development or behavior. During one of two adolescent periods, the rats were given repeated injections of 5 mg/kg or 20 mg/kg of 5-MeO-DIPT or a corresponding volume of isotonic saline. After the animals reached adulthood, they were trained and tested on a number of tasks designed to assess the impact of 5-MeO-DIPT, if any, on spatial memory, presumably involving declarative memory systems as well as a nonspatial task that is considered sensitive to disruptions in nondeclarative memory. Both the 5-MeO-DIPT- and saline-treated rats were able to master spatial navigation tests where the task included a single goal location and all groups performed comparably on these phases of training and testing. Regardless of exposure level during adolescence, the performance of the drug-treated rats was markedly inferior to that of the control animals on a task where the goal was moved to a new location and on a response learning task, suggesting a lack of flexibility in adapting their responses to changing task demands. Detected reductions in serotonin activity in the forebrain similar to the effects of extensively investigated compounds such as methylenedioxymethamphetamine (MDMA), suggest that 5-MeO-DIPT may produce its adverse effects by compromising serotonergic systems in the brain.

A consolidation of powders using the KOBO method at elevated temperature was elaborated for production of Al/SiC metal matrix composite (MMC). The observations of the mean strain and inelastic strain range during the force controlled high cycle fatigue (HCF) tests identified the ratcheting mechanism combined with mechanism characterized by cyclic plasticity. Damage parameters were calculated on the basis of strain signal acquisition during fatigue tests. Fatigue properties, creep resistance and lifetime of Al/SiC MMC were gradually improved with the increase of the SiC particles content. The microstructural observations of the material before and after tests were also performed.

The experimental identification of fatigue damage mechanisms and evaluation of their development rate, based on changes in material respond on cycle loading, has been presented in the work. The research has been conducted on hyper-eutectic cast alloy AlSi8Cu3. The microstructure and fracture analyses were performed. The high cycle fatigue tests were conducted with frequency of 20 Hz under constant nominal stress amplitude with monitoring the strain response of material during the test. The ratcheting was found as the main mechanism of the fatigue damage. It was established that the linear fatigue accumulation law should not be used for fatigue life prediction in case of the tested cast aluminum alloy.

We present results on transverse momentum correlations of charged particle pairs produced in Pb Au collisions at 158 A GeV / c at the Super Proton Synchrotron. The transverse momentum correlations have been studied as a function of collision centrality, angular separation of the particle pairs, transverse momentum and charge sign. We demonstrate that the results are in agreement with previous findings in scale-independent analyses at the same beam energy. Employing the two-particle momentum correlator 〈 Δ p t , i , Δ p t , j 〉 and the cumulative p t variable x ( p t ) , we identify, using the scale-dependent approach presented in this paper, different sources contributing to the measured correlations, such as quantum and Coulomb correlations, elliptic flow and mini-jet fragmentation.

We present a measurement of $e^+e^-$ pair production in central Pb-Au collisions at 158$A$ GeV/$c$. As reported earlier, a significant excess of the $e^+e^-$ pair yield over the expectation from hadron decays is observed. The improved mass resolution of the present data set, recorded with the upgraded CERES experiment at the CERN-SPS, allows for a comparison of the data with different theoretical approaches. The data clearly favor a substantial in-medium broadening of the $\rho$ spectral function over a density-dependent shift of the $\rho$ pole mass. The in-medium broadening model implies that baryon induced interactions are the key mechanism to in-medium modifications of the $\rho$-meson in the hot fireball at SPS energy., Comment: Revised version

Recent results of the CERES experiment at the CERN SPS on low-mass electron pair analysis and ϕ → K + K − are discussed and compared to models.

This paper presents an investigation into the sooting characteristics of isolated droplets (for fuel n -decane) burning in heated ambients in microgravity. A backlit video view of the droplet was taken to determine the soot shell size and to judge the transient soot generation according to qualitative amount of soot. The independent experiment variables were the ambient temperature and initial droplet diameter. Soot generation was higher for initially larger droplets when compared at the same burning time normalized with the initial droplet diameter squared (called normalized burning time). At the same absolute burning time there existed an obvious initial transient period after ignition in which the stated relationship was not satisfied. This transient time increased with increasing the ambient temperature. There was a peak in the soot generation at about 1000 K throughout the lifetime of the droplet. The soot shell size was generally larger for an initially bigger droplet at the same instantaneous droplet diameter or normalized burning time. At the same absolute burning time, however, an initially smaller droplet exhibited larger relative soot shell sizes (the soot shell size normalized with the initial droplet diameter). The soot shell size increased monotonically with increasing ambient temperature. This is due to the increase in the Stefan flow drag with the larger burning rate at the higher temperature. The consequent result is that the soot shell sizes are much larger for droplets burning in heated ambients than for droplets burning in room-temperature ambients.

Background & aims: Surgical fundoplication has been recommended for children with persistent GERD. The purpose of this study was to determine the frequency of postoperative symptoms requiring medical evaluation and/or treatment after fundoplication in children with or without associated medical disorders. Methods: In a retrospective cohort study, we reviewed the medical records of all children who underwent fundoplication during 1996–1999. Data were collected to analyze the following: (1) postoperative complications, (2) postoperative symptoms, (3) procedures performed to evaluate postoperative symptoms, (4) medical treatment, and (5) repeat surgery. Results: A total of 198 children underwent fundoplication, and 176 (89%) came for follow-up evaluation within 2 months after surgery. The median age at the time of surgery was 2.1 y (range, 6 mo–18 y) and the median duration of follow-up was 2.0 y (range, 1.2–4.8 y). A total of 130 (74%) children had one or more associated medical disorders including neurodevelopmental delay (70%), cystic fibrosis (8%), tracheoesophageal anomalies (8%), bronchopulmonary dysplasia (8%), and reactive airway disease (35%). Postoperatively, children with associated medical disorders had a higher frequency of lung infections (52% vs. 22%, P = .03) and dumping syndrome (2% vs. 0%, P = .05). Most children (63%) received evaluation and treatment for symptoms suggestive of recurrent reflux despite fundoplication. Conclusions: Nearly two thirds of children who received fundoplication and were followed-up within 2 months after surgery either have symptoms or receive medical therapy for reflux. Fundoplication for the control of GERD in children needs further evaluation.

In quiescent ambiences the burning rate of an isolated liquid fuel droplet varies with the droplet’s initial diameter d 0 due to the close surrounding of the droplet in the flame and the subsequent strong action of flame heat, in balance with its loss to ambience, on burning. Suppressing the influence of d 0 on burning rate was recognized in this communication through burning the droplet in a forced convective flow that sweeps the flame off the droplet to weaken the action of flame heat on burning. The d 0 -dependent k 0 , however, affected the correlation k = k 0 (1+ C · Re 0.5 ) for the burning rate in convective flows, where k 0 and k are the burning rate constants, respectively, in the equi-temperature quiescent and convective-flow ambiences, and Re is the flow’s Reynolds number with respect to d 0 . Different correlation constants C were acquired when using different d 0 and its corresponding k 0 to fit the correlation. In hot conditions (633 K in this article) k 0 is bigger for larger d 0 , causing a smaller constant C when taking a larger d 0 for the correlation. Against this, k 0 is lower for larger d 0 in room-temperature ambiences, which resulted in the mutual compensation of the effects from k 0 and d 0 on C such that C is basically independent of the values of d 0 and k 0 . Besides, the communication showed that C was larger for the gas flow with a higher temperature, revealing an increase in the effect of Re on burning with raising the gas temperature.

Isolated droplet burning were conducted in microgravity ambiences of different temperatures to test the initial diameter influence on droplet burning rate that shows a flame scale effect and represents an overall thermal action of flame in balance with heat loss. The coldest ambience examined was room air, which utilized a heater wire to ignite the droplet. All other ambiences hotter than 633 K were acquired through an electrically heated air chamber in a stainless steel can. An inverse influence of initial droplet diameter on burning rate was demonstrated for the cold and hot ambiences. That is, the burning rate respectively decreased and increased in the former and latter cases with raising the initial droplet diameter. The reversion between the two influences appeared gradual. In the hot ambiences the burning rate increase with increasing the initial droplet diameter was larger at higher temperatures. A “net heat” of flame that denotes the difference between “heat gain” by the droplet and “heat loss” to the flame surrounding was suggested responsible for the results. In low-temperature ambiences there is a negative net heat, and it turns gradually positive as the ambience temperature gets higher and the heat loss becomes less. Relating to luminous flame sizes and soot generation of differently sized droplets clarified that the flame radiation, both non-luminous and luminous, is determinative to the net heat in microgravity conditions. In addition, the work identified two peak values of soot generation during burning, which appeared respectively at the room temperature and at about 1000 K. The increase in ambience temperature made also bigger soot shells. The heat contribution of flame by both radiation and conduction was demonstrated hardly over 40% in the total heat required for droplet vaporization during burning in a hot ambience of 773 K.

This report presents an investigation on the combustion of single droplets comprised of heavy oil and oil mixtures blending diesel light oil (LO) and a heavy oil residue (HOR). The tests were conducted in a microgravity facility that offered 10 s of free-fall time. Fine wire thermocouples supported the droplets, resulting in a measurement of droplet temperature history. Additional data were the droplet and flame size history. The results identified four distinctive burning stages between ignition and extinction for heavy oil (C class) and HOR–LO blends. They are, in succession, the start-up, inner evaporation, thermal decomposition (pyrolysis) and polymerization stages. The start-up stage denoted an initial transient period, where the LO components burned from the droplet surface and the droplet temperature increased rapidly. The latter three stages featured pronounced droplet swellings and contractions caused by fuel evaporation and decomposition inside the droplet. An evaporation temperature demarcated the start-up stage from the inner evaporation stage, and this temperature corresponded to a plateau in the temperature history of the droplet. Two additional temperatures, termed the decomposition and polymerization temperatures, indicated the ends of the evaporation and decomposition stages. These temperatures were similarly identified by plateaus or inflection points in the time–temperature diagram. The evaporation temperature gradually decreased with increasing the initial LO mass fraction in the droplet, whereas the other two temperatures were almost independent of the oil composition. All three temperatures increased with decreasing initial droplet diameter, but the dependence was very slight. Based on the results, the combustion of heavy oil droplets appears to be dominated by a distillation-like vaporization mechanism, because of the rapid mass transport within the droplets caused by the disruptive burning.

This paper presents the results of an experimental investigation into the extinction behavior of single droplets and binary droplet arrays of decane fuel in normal gravity and microgravity. The test ambients were air at reduced pressure for the normal gravity experiments and nitrogen/oxygen and helium/oxygen at reduced pressure for the microgravity experiments. The data show that interaction effects have a stronger influence on the extinction behavior of a binary array than the quasi-steady burning behavior. In normal gravity, the burning rate constant is only a very weak function of the interdroplet spacing at initial nondimensional separation distances greater than 5. The extinction droplet diameter, however, is much smaller (if it exists) for the droplet array at an instantaneous non-dimensional spacing of approximately 20. The microgravity experiments in nitrogen/oxygen (0.15 oxygen mole fraction) ambients exhibited different extinction behavior than the normal gravity tests. In this ambient condition, the flame surrounding the binary array always extinguished at a larger droplet diameter compared with single droplets. The microgravity experiments in the helium/oxygen (0.25 oxygen mole fraction) ambients exhibited behavior opposite of the nitrogen diluted tests with the binary array extinguishing at smaller droplet diameters than a single droplet. For the microgravity experiments, the observed difference between the two ambients is attributed to the importance of radiative loss. The nitrogen/oxygen tests had larger, weaker flames and smaller burning rates and consequently were affected more significantly by radiative loss from the flame zone compared to the helium/oxygen tests. A qualitative explanation of the different extinction behavior is detailed in the paper.

This paper presents an experimental evaluation of the effects induced in the selected engineering alloys (brass and aluminium alloy) by annealing and ageing. Both materials were tested in the as-received state and after annealing. In the case of brass, an influence of the ageing process on the subsequent mechanical properties under complex monotonic loading was also investigated. An analysis of the experimental data is based on the concept of the yield surface determined in the two-dimensional stress space (σ, τ). The materials in the as-received state exhibit an initial anisotropy coming from the manufacturing processes applied to produce rods used as the blanks for specimens. In order to remove the initial anisotropy, a few different types of the annealing processes were applied. To assess an evolution of the mechanical properties of brass due to the ageing process, the subsequent yield surfaces were determined after different time periods measured with respect to the annealing. It was shown that the residual stresses removed from brass using the annealing process arose again in this material due to the ageing phenomenon which took place during the long-term storage at room temperature.

This paper presents the results of an experimental investigation on the combustion of single droplets and two-droplet arrays of pure methanol and methanol/dodecanol mixtures in air under microgravity conditions. The initial droplet diameters, d 0 , were nominally 0.9 mm. The independent experimental variables were the ambient pressure (0.1–9.0 MPa), fuel mixture ratio (methanol/dodecanol: 100/0–15/85), and interdroplet separation distance l ( l / d 0 = 2.3–8.0). For pure methanol, the results show that the droplet lifetime decreases with increasing interdroplet separation distances at low pressures. At higher pressures (3.0 MPa and above) the droplet lifetime was independent of separation distance. The flame extinguished at a finite droplet size only for pure methanol at 0.1 MPa, in qualitative agreement with theoretical predictions. The extinction droplet diameter was nearly independent of the droplet spacing. Methanol/dodecanol–mixture droplets exhibited microexplosion for both single droplets and droplet arrays. The paper presents maps of the disruption regime for both single droplets and droplet pairs. The difference between the disruptive behavior of single droplets and droplet pairs is explained by differences in liquid-phase circulation induced by the gas-phase asymmetry of the droplet pair. The paper also presents results of the dependence of the onset of disruption (in terms of both volume and time) on the pressure and initial fuel mixture ratio.

This paper presents results of an experimental investigation on acoustic effects on combustion of single droplets and droplet pairs in microgravity. The ambient gas was air at atmospheric temperature and pressure, with octane as the fuel. A loudspeaker at the bottom of the chamber produced the acoustic field. Experimental results of single droplets showed that at low frequency and small to moderate acoustic intensities the evaporation rate increases, and the burning rate constant is nearly proportional to the product of frequency, f, and square of displacement, Xa2, fXa2. At higher acoustic intensities, the burning rate constant either remains constant or decreases, and in some cases, flame extinction occurs at a finite droplet diameter. The burning rate constant for a droplet pair is consistently lower than that for a single droplet. At lower frequencies, the burning rate constant reaches a maximum at an intermediate acoustic intensity. At higher frequencies, the burning rate constant increases monotonically with increasing acoustic intensity. The flame size decreases as a result of interactions, as does the critical spacing that indicates a merged flame around the droplet pair versus individual flames surrounding the droplets. The results also show that interactions stabilize the flame, in that droplet pairs burn to completion under conditions in which the flame surrounding a single droplet extinguishes at a finite droplet diameter.

The interactive combustion of two miscible binary-fuel droplets at elevated pressures, up to the values above the critical pressure of the fuel, was investigated experimentally. Heptane and hexadecane were selected as the fuel mixture, to study the occurrence of staged combustion, and a nitrogen-oxygen atmosphere with a relatively low oxygen concentration was employed to facilitate observation of droplets during combustion at elevated pressures. The effects of fuel composition, ambient pressure, and droplet spacing were investigated. Results show that staged combustion of binary-fuel droplets still exists for interacting droplets at high pressure and that burning-rate constants of the first and the third stages, as well as the transition droplet volume, are not strongly affected by interaction. The increase in droplet lifetime by strong interaction is demonstrated and explained. It is shown that the lifetime achieves a minimum value at a critical droplet spacing even for binary-fuel droplets that undergo staged combustion at high pressure without buoyancy, a result which is explained by influences of radiant energy transfer. It is also demonstrated experimentally that flame lifetimes exceed droplet lifetimes at high pressure both for single droplets and strongly interacting droplet pairs, which is explained by vapor presence after liquid disappearance and reduced tendencies toward flame extinction at elevated pressures.

The objective of this research is to improve the understanding of droplet interaction in combustion of binary fuel droplets at high pressure. Combustion experiments were performed on two fiber-supported droplets of n -heptane/ n -hexadecane mixtures in room-tempperature air at pressures from 0.1 MPa to 6 MPa under free-fall microgravity conditions. The burning lifetime of the interacting droplets is compared with that of single droplet. The results show that the pressure dependence of the burning lifetime for the interacting droplets is similar to that of a single droplet. For most mixtures, the burning lifetime reaches a minimum value at pressures well above the critical pressure of either of the pure fuels. The interactive effects are evaluated using the total interaction coefficient, which is the ratio of the burning lifetime of the interacting droplets to that of a single droplet. As the pressure increases, the total interaction coefficient increases slightly and then decreases. The total interaction coefficient is a minimum for a certain initial liquid-phase mixture concentration. At relatively low pressure, the interactive effects are explained by the use of the quasi-steady interaction coefficient and temporal variation of the droplet diameter squared for a single droplet. At high pressures, the decrease in the influence distance of the droplet with increasing pressure causes the decrease in the total interaction.

Background National Comprehensive Cancer Network (NCCN) guideline compliance for breast cancer was determined in a breast center. Methods A retrospective study of 200 new breast cancer patients seen in 2004 was performed. Results NCCN guideline compliance rates for preoperative evaluation, breast surgery, lymph node surgery, radiation treatment, and systemic adjuvant therapy were 87%, 97%, 97%, 77%, and 63%, respectively. The most common reasons for noncompliance were partial breast radiation, no radiation, limited life expectancy, and patient choice to defer systemic treatment. Conclusions The investigation of quality of breast cancer care requires measurement of compliance and reasons for noncompliance with established guidelines. A review that focuses only on percentage compliance has the potential to penalize institutions that (1) practice informed consent detailing absolute risks of survival with and without systemic therapy, (2) practice evidence-based medicine before the standardized guideline is changed to reflect it, and (3) serve populations with limited life expectancy.

This paper examines Bayesian analysis as a tool for predicting both reliability growth and reliability of censored multi-level, multi-stress accelerated life tests. The methodology is examined using the Dirichlet prior distribution in reliability growth applications and in randomly ordered accelerated life tests occurring in designed experiments (DOE). A simulation is used to examine the utility and accuracy of the approach both graphically and statistically. The results are both enlightening and conclusive

Experimental analysis of the plastic properties for both an aged pure copper and the same material subjected to various types of predeformation is presented. The analysis was made by studying; the position in stress space and by determination of dimensions of the yield surfaces. The initial yield surface has been determined using the probing technique of a single specimen and this surface was used as the starting point for comparative studies of yield surfaces of the prestrained material. The material predeformations of the same magnitude were induced either by a creep process at elevated temperature or by monotonic loading at ambient temperature. After required values of plastic prestrain were attained, yield surfaces were determined by the same method as for the non-prestrained material. The anisotropic yield condition was used to create a least squares fit of the experimental data.

Individual droplets with diameters ranging from about 2 mm to 5 mm were burned under microgravity conditions in air at 1 bar with an ambient temperature of 300 K. Each droplet was tethered by a silicon carbide fiber of 80 μm or 150 μm diameter to keep it in view of video recording, and, in some tests, a forced air flow was applied in a direction parallel to the fiber axis. Methanol, two methanol-water mixtures, two methanol-dodecanol mixtures, and two heptane-hexadecane mixtures were the fuels. Droplet diameters were measured as functions of time, and they are compared here with existing theoretical predictions. The prediction that methanol droplets extinguish at diameters that increase with increasing initial droplet diameter is verified by these experiments. In addition, the quasi-steady burning-rate constant of the heptane-hexadecane mixtures appears to decrease with increasing droplet diameter; obscuration consistent with very heavy sooting, but without the formation of soot shells, is observed for the largest of these droplets. Forced convective flow around methanol droplets was found to increase the burning rate and to produce a ratio of downstream to upstream flame radius that remained constant as the droplet size decreased, a trend in agreement with earlier results obtained at higher convective velocities for smaller droplets having larger flame standoff ratios. Implications of the experimental results regarding droplet-combustion theory are discussed.

Environmental Stress Screening (ESS) is employed to reduce, if not eliminate, the occurrence of early field failures. In this paper, a three level ESS model is presented for a complex electronic system. Screening is performed at the component, board and system level. Components are screened for a specified duration before being assembled into printed circuit boards (PCBs). Defects introduced during the assembly of the PCBs are screened at the board level, while defects introduced during final assembly are screened at the system level. Components and connections are assumed to come from good and substandard populations and their times-to-failure distributions are modeled by mixed distributions. Mixed exponential distributions are used to model component timesto-failure and mixed Weibull distributions are used to model the times-to failure for board and system level connections. The mixed Weibull distributions are used to model wear-out characteristics at the board and system level. Optimal screen durations in the presence of wear-out are obtained by minimizing the systems life-cycle cost. ESS is shown to be a cost effective strategy when properly implemented. The optimal screening strategies are shown to be relatively robust to the system warranty period.

Series transfer lines provide the modern manufacturing facility with an orderly and efficient method of product assembly. Sequential tasks are assigned to specific workstations along the line. Buffers between the workstations provide on-line inventories to regulate product flow along the line. Previous reliability or availability analysis of these lines employed continuous-time Markov chain models. The analysis here focuses on recent developments in discrete-time Markov modeling of lines with unreliable workstations and nonfailing buffers. Specifically, this paper demonstrates a more stable and efficient computation of stationary-state workstation buffer model probabilities for unreliable lines. In addition, a highly efficient algorithm was developed to isolate and remove transient states from the model. Finally, a regression analysis linear model was developed to predict the effects of changing individual workstation availabilities and buffer capacities on overall line availability.

The spark ignition characteristics of a bidisperse aerosol were investigated. The purpose of the investigation was to determine the parameter(s) of the droplet size distribution that best correlates the ignition behavior of a spray. Two monodisperse aeeosols, generated by identical Berglund-Liu monodisperse aerosol generators, were used to create the bidisperse spray. A Phase Doppler Particle Analyzer was used to measure the droplet size distribution, droplet flux, droplet velocity and gas velocity at the spark gap. A capacitive discharge ignition system was used to generate the spark which ignited the mixture. Mixtures of oxygen and nitrogen were used as the oxidizing gas instead of air. The results show that the Sauter mean diameter correlates the ignition of the bidisperse sprays very well. The arithmetic, area, and volume mean diameters do not correlate the ignition behavior at all. In fact, in some cases, the arithmetic, area, and volume mean diameters exhibit a trend where the ignition energy decreases with, increasing droplet size. Comparison with monodisperse data also demonstrated that the Sauter mean diameter adequately describes the ignition of the bidisperse sprays. A semi-empirical characteristic time model was used to model the spark ignition of the sprays. The model was extended to include the effects of finite rate chemistry. The model correlated the ignition behavior of the bidisperse spray quite well. The best correlation was obtained by using the Sauter mean diameter consistent with the results of the experimental program.