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In the 2015 review paper ‘Petawatt Class Lasers Worldwide’ a comprehensive overview of the current status of high-power facilities of
was presented. This was largely based on facility specifications, with some description of their uses, for instance in fundamental ultra-high-intensity interactions, secondary source generation, and inertial confinement fusion (ICF). With the 2018 Nobel Prize in Physics being awarded to Professors Donna Strickland and Gerard Mourou for the development of the technique of chirped pulse amplification (CPA), which made these lasers possible, we celebrate by providing a comprehensive update of the current status of ultra-high-power lasers and demonstrate how the technology has developed. We are now in the era of multi-petawatt facilities coming online, with 100 PW lasers being proposed and even under construction. In addition to this there is a pull towards development of industrial and multi-disciplinary applications, which demands much higher repetition rates, delivering high-average powers with higher efficiencies and the use of alternative wavelengths: mid-IR facilities. So apart from a comprehensive update of the current global status, we want to look at what technologies are to be deployed to get to these new regimes, and some of the critical issues facing their development.
Staphylococci have been isolated from various sites of the body of healthy sheep, as well as from many infections of those animals, the main one being mastitis. The objective of this review is to appraise the importance and significance of staphylococci in causing mastitis in ewes. The review includes a brief classification and taxonomy of staphylococci and describes the procedures for their isolation and identification, as well as their virulence determinants and the mechanisms of resistance to antibacterial agents. Various staphylococcal species have been implicated in staphylococcal mastitis and the characteristics of isolates are discussed with regards to potential virulence factors. Staphylococcal mastitis is explicitly described, with reference to sources of infection, the course of the disease and the relevant control measures. Finally, the potential significance of staphylococci present in ewes’ milk for public health is discussed briefly.
Inverting an evolving diffusive scalar field to reconstruct the underlying velocity field is an underdetermined problem. Here we show, however, that for two-dimensional incompressible flows, this inverse problem can still be uniquely solved if high-resolution tracer measurements, as well as velocity measurements along a curve transverse to the instantaneous scalar contours, are available. Such measurements enable solving a system of partial differential equations for the velocity components by the method of characteristics. If the value of the scalar diffusivity is known, then knowledge of just one velocity component along a transverse initial curve is sufficient. These conclusions extend to the shallow-water equations and to flows with spatially dependent diffusivity. We illustrate our results on velocity reconstruction from tracer fields for planar Navier–Stokes flows and for a barotropic ocean circulation model. We also discuss the use of the proposed velocity reconstruction in oceanographic applications to extend localized velocity measurements to larger spatial domains with the help of remotely sensed scalar fields.
We develop a political history of Wards Cove v. Atonio (1989) to show how Robert Cover's concepts of jurisgenesis and jurispathy can enrich the legal mobilization framework for understanding law and social change. We illustrate the value of the hybrid theory by recovering the Wards Cove workers’ own understanding of the role of litigation in their struggle for workplace rights. The cannery worker plaintiffs exemplified Cover's dual logic by articulating aspirational narratives of social justice and by critically rebuking the Supreme Court's ruling as the “death throe” for progressive minority workers’ rights advocacy. The cannery workers’ story also highlights the importance of integrating legal mobilization scholars’ focus on extrajudicial political engagement into Cover's judge‐centered analysis. Our aim is to forge a theoretical bridge between Cover's provocative arguments about law and the analytical tradition of social science scholarship on the politics of legal mobilization.
Jeannine Bell's Hate Thy Neighbor: Move In Violence and the Persistence of Racial Segregation in American Housing provides an account of racist violence as a tool for maintaining housing segregation that challenges perceptions of rising tolerance and demonstrates the importance of understanding racism as a structural feature of social organization. Bell shows how some perpetrators of move in violence deploy claims about “property values” as a defense against charges of racism. The use of such claims starkly illustrates how colorblind racism allows assertions of racial privilege to resonate as neutral articulations of rational self-interest. The desire to defend racial privileges persists as a significant practical barrier to racial equality even when tolerance increases.
The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)–pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D–pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (Prace difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (Prace difference=0·56). Among EA, the 25(OH)D–FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.
Space represents a rather hostile environment for the human body, with the bone loss being one of the most important consequences. Autophagy is a complex cellular process contributing to several cellular processes including recycling, nutrition, apoptosis and response to stressful environments. Recent reports have indicated that autophagy is a process that increases under microgravity conditions. In particular, this was shown to be true in skeletal cells such as the osteoclasts. Suppression of autophagy results in downregulation of osteoclastogenesis, making autophagy a quite tempting therapeutic target for preventing bone loss during space flights. The present work attempts to review the literature on the topic of autophagy role in osteoclastogenesis under microgravity conditions.
The first publication dealing with materials which have since come to be included in the Tchefuncte horizon was an article by J. R. Czajkowski, published in the Louisiana Conservation Review for July 1, 1934. This was a brief summary of the first six months' exploration by a Civil Works Administration project of extensive shell deposits near Little Woods, Louisiana, along the shores of Lake Pontchartrain, east of New Orleans. All of these middens had been used as sources of shell for paving roads; consequently the center of each had been gutted previous to Czajkowski's work. Through arrangements made by Dr. Fred B. Kniffen, the materials and notes were to be turned over to Louisiana State University. Only a very small part of the collection, however, was received by the University; the remainder could not be located. The few notes obtainable were from the brief field diary of one of the foremen.
What is available of Czajkowski's collection has been used in this paper. It represents only a part of the enormous amount found, and because of the lack of notes and identifying marks it necessarily must be treated as a collection from all the middens which Czajkowski dug (see map, Fig. 2, Sites Or-1, Or-2, Or-3, Or-4 and Or-5). This is a particularly unfortunate situation, for these areas were so thoroughly disturbed that later investigations have succeeded in collecting very little information.
The only excavations of Tchefuncte sites which produced materials suitable for laboratory analyses of the temporal behavior of the pottery types characteristic of the period were those undertaken at the Tchefuncte middens and Big Oak Island. In Tchefuncte midden A, five hundred five-foot squares were dug to the bottom of the midden by six-inch levels. For purposes of analysis, adjoining squares of uniform total depth were grouped together in order to provide large units suitable for stratigraphic studies. These units were selected in the parts of the midden where the strata were most nearly horizontal. Areas on the periphery, or in which burials occurred, were not used for stratigraphic analysis. The various units, their size, and depth are as follows:
By means of these analysis units, not only are the trends of popularity of the pottery types of the Tchefuncte period made apparent, but also the relative temporal position of the Tchefuncte complex is conclusively shown.
In this section of the report we have described the artifacts representative of the Tchefuncte culture as a whole. These artifacts were made of pottery, stone, bone, and shell—pottery vessels, however, are described in the next chapter.
Clay Tubular Pipes.—Tubular pipes made of fired clay are a diagnostic trait of the Tchefuncte period (Fig. 7). Complete specimens averaged about 15 cm. in length and the stem diameter increases gradually from about 1.5 cm. to 2 cm. which is the average diameter of the tobacco chamber. Frequently these pipes have flattened mouth pieces (Fig. 7 a, d, f, p, q, s, t). A few specimens exhibit slight shoulders between the stem and the tobacco chamber (Fig. 7 l, m) and a few others have slightly flaring rims (Fig. 7 c, k).
In most of the specimens there is a slight interior constriction between the tobacco chamber and the stem. The bore tapers gradually from the chamber to the mouthpiece where it has an average diameter of 6 mm. The tobacco chambers have an average interior diameter of 16 mm. About one-half of any pipe is tobacco chamber and the other half is stem.
It appears that in the original excavations of the Little Woods site Czajkowski found skeletons in the middens at different points. The following is taken from his article in the Louisiana Conservation Review:
Most of the burials on the shell ridge were solitary and no funeral furniture or artifacts were found with them, with two exceptions: (1) On March 20th, two skeletons were found in a semi-flexed, east-west position. The following day, five more skeletons were uncovered, making a total of seven, all lying in the same position, parallel to each other about four feet apart, at a depth of about five feet …(2) On June 1st at a depth of six feet, a single skull impaled on a tree stump was found. Underneath the skull was a single fragment of decorated pottery.
Burial Ground: Seven skeletons found on March 20th, 950 feet northwest from the location. Adults, in fairly good condition; all skulls crushed except one…. Six in semi-flexed position on their backs … (the illustration to which Czajkowski here refers shows a fully flexed skeleton). All lying parallel in an east-west position with their heads west. The seventh at full length on its face. They were lying at a depth of about four feet from the surface and overlain with a shell bed from two to twelve inches in thickness. The distance between the skeletons was from three to four feet (Czajkowski, 1934, pp. 14-15).
The pottery from the sites of the Tchefuncte period has been classified into a number of different types. As used by us, the type is a kind of average of an arbitrarily limited range of overlapping traits which have been abstracted from whole vessels and sherds that appear to be similar. Typology is checked against stratigraphy and stratigraphy against typology, to determine the utility of the type as an indicator of cultural change in time and space. Following are descriptions of the pottery types found in sites of the Tchefuncte period.
Paste.—Method of Manufacture: Coiled. Sherds break readily along coil junctions. Flattened coils average 3-4 cm. wide.
Tempering: Angular particles of clay. Small amount of fine sand. There are occasionally small particles of carbonized vegetal material and rarely bits of red ochre.
Texture: Clay of paste is very fine. Clay was very poorly wedged, and this feature, added to the large angular tempering particles, gives a laminated and contorted appearance to cross sections of sherds. Surfaces have been floated and are soft and chalky.
A comparison of Tchefuncte traits suggests that there are three groupings or foci which at present comprise the Tchefuncte culture. The Copell site on Pecan Island, although a single site, represents the first group. The absence of pottery, presence of artifacts with burials, interment in a cemetery, and other traits tend to isolate this component from other Tchefuncte groupings.
The three shell midden sites, Tchefuncte, Little Woods, and Big Oak Island form another grouping. The construction and use of shell middens, presence of certain types of bone and shell artifacts, and styles of chipped flint projectile points differentiate these midden sites from the others.
The third grouping is represented by the two mound sites, Lafayette and Lake Louis. The traits of circular mounds, differences in the styles of projectile points, and absence of other Tchefuncte traits delimit this focus.
A number of traits held in common, or traits which overlap from one component or site to another, link all of these groupings together to form the Tchefuncte culture. For instance, burial traits and styles of bone implements link the Copell site with the midden sites of the Tchefuncte period. The midden sites and the mound sites are bound together by common types of pottery and pipes. For the reader who disagrees with our interpretations, or who has a better method, we have listed all of our traits in the summaries of each component (Chapter II).
Gas turbine engines are prone to the phenomenon of thermoacoustic instability, which is highly detrimental to their components. Recently, in turbulent combustors, it was observed that the transition to thermoacoustic instability occurs through an intermediate state, known as intermittency, where the system exhibits epochs of ordered behaviour, randomly appearing amidst disordered dynamics. We investigate the onset of intermittency and the ensuing self-organization in the reactive flow field, which, under certain conditions, could result in the transition to thermoacoustic instability. We characterize this transition from a state of disordered and incoherent dynamics to a state of ordered and coherent dynamics as pattern formation in the turbulent combustor, utilizing high-speed flame images representing the distribution of the local heat release rate fluctuations, flow field measurements (two-dimensional particle image velocimetry), unsteady pressure and global heat release rate signals. Separately, through planar Mie scattering images using oil droplets, the collective behaviour of small scale vortices interacting and resulting in the emergence of large scale coherent structures is illustrated. We show the emergence of spatial patterns using statistical tools used to study transitions in other pattern forming systems. In this paper, we propose that the intertwined and highly intricate interactions between the wide spatio-temporal scales in the flame, the flow and the acoustics are through pattern formation.
OBJECTIVES/SPECIFIC AIMS: The objective of this study was to determine if trimethylamine N-oxide (TMAO) alone could acutely alter cardiac contractile function on a beat-to-beat basis. METHODS/STUDY POPULATION: CD1 adult mouse hearts were extracted, attached to a force transducer, oxygenated, and paced within an organ bath. Changes in contractility were measured after pipetting or reverse perfusing TMAO through the aorta via a modified Langendorff apparatus to facilitate TMAO delivery into the myocardium. To determine if our findings translated to the human heart, we performed contractility experiments using human right atrial appendage biopsy tissue retrieved during cardiopulmonary bypass procedures. To investigate whether TMAO alters contractile rate, in a separate series of experiments, the atria and sinoatrial node of isolated hearts were kept intact to allow for spontaneous beating without artificial pacing and were treated with TMAO or vehicle. In addition, intracellular calcium measurements were performed on spontaneously beating embryonic rat cardiomyocytes after TMAO or vehicle treatment. RESULTS/ANTICIPATED RESULTS: We found acute exposure to TMAO, diluted into the organ bath, increased average contraction amplitude 20% and 41% at 300 µM and 3000 µM, respectively (p<0.05, n=6). Langendorff reverse perfusion of mouse hearts ex vivo with 300 µM TMAO generated an even greater response than nonperfusion peripheral exposure and increased isometric force 32% (p<0.05, n=3). Consistent with what we observed in mouse hearts, incubation of human atrial muscle tissue with TMAO at 3000 µM increased isometric tension 31% compared with vehicle (p<0.05, n=4). TMAO treatment (3000 µM) also increased average beating frequency of ex vivo mouse hearts by 27% compared with vehicle (p<0.05, n=3) and increased the spontaneous beating frequency of primary rat cardiomyocytes by 13% compared with vehicle treatment (p<0.05, n=4). DISCUSSION/SIGNIFICANCE OF IMPACT: TMAO, at pathological concentrations, directly increases the force and rate of cardiac contractility. Initially, these inotropic and chronotropic effects may be adaptive during CKD; however, chronic increases in isometric tension and beating frequency can promote cardiac remodeling and heart failure. Further translational studies are needed to understand the intricate relationship between the microbiome, kidneys, and heart and to examine if TMAO represents a therapeutic target for reducing cardiovascular mortality in CKD patients.