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We present progress in utilizing a machine learning (ML) assisted optimization framework to study the trends in a parameter space defined by spectrally shaped, high-intensity, petawatt-class (8 J, 45 fs) laser pulses interacting with solid targets and give the first simulation-based overview of predicted trends. A neural network (NN) incorporating uncertainty quantification is trained to predict the number of hot electrons generated by the laser–target interaction as a function of pulse shaping parameters. The predictions of this NN serve as the basis function for a Bayesian optimization framework to navigate this space. For post-experimental evaluation, we compare two separate neural network (NN) models. One is based solely on data from experiments, and the other is trained only on ensemble particle-in-cell simulations. Reviewing the predicted and observed trends across the experiment-capable laser parameter search space, we find that both ML models predict a maximal increase in hot electron generation at a level of approximately 12%–18%; however, no statistically significant enhancement was observed in experiments. On direct comparison of the NN models, the average discrepancy is 8.5%, with a maximum of 30%. Since shot-to-shot fluctuations in experiments affect the observations, we evaluate the behavior of our optimization framework by performing virtual experiments that vary the number of repeated observations and the noise levels. Here, we discuss the implications of such a framework for future autonomous exploration platforms in high-repetition-rate experiments. [ABSTRACT FROM AUTHOR]

Four previously unrecognized neotectonic fault scarps in southwest Namibia are described. These relatively straight, simple but segmented structures are 16–80 km long and have measured vertical separations of 0.7–10.2 m. We estimate that each is capable of producing earthquakes of Mw 6.4 or greater, indicating that large earthquakes may occur despite limited cumulative displacement. There is strong evidence that some of these scarps were formed by repeated earthquakes. Comparison with aeromagnetic and geological maps reveal that the normal faults reactivate major crustal weaknesses that are orientated north‐south and northwest‐southeast and perpendicular to the local gravitational potential energy gradient. The presence of these structures in an area with a limited record of instrumental seismicity suggests that the Mmax of this region may be much larger than generally assumed. They highlight the necessity of incorporating information from fault studies into probabilistic seismic hazard assessments in this region, in a similar way to other stable continental regions such as Australia. The fact that such major structures have gone hitherto unrecorded suggests significant further research is needed to characterize these sources of hazard. The identification of an apparent cluster of large magnitude neotectonic earthquakes in the area may be related to the exceptional preservation potential of scarps rather than indicating an area of comparatively rapid deformation. If this interpretation is correct, then these scarps represent an important indication of the potential seismic hazard across the region, and the occurrence of infrequent large‐magnitude seismicity on similar structures should be considered throughout southwestern Africa. Plain Language Summary: Namibia is considered to be a region that has very few large earthquakes. This is partly because previously evidence has not been found in the landscape to suggest that many large earthquakes have occurred in the past. However, in this study we show evidence in SW Namibia of four previously unidentified but significant fault scarps (steps in the landscape generated by movement during earthquakes). These features indicate that significant earthquakes can and have occurred in southern Namibia in the geologically recent past. We also find evidence for repeated motion along these faults and therefore repeated earthquake generation. The extremely dry climate and abundance of hard, well‐cemented sediments in the Namib Desert makes it one of the best places in the world for preserving fault scarps. This means we can get a much better idea of the type of earthquakes which could occur over relatively long timescales, and we find evidence for much larger events than would previously have been expected in this area. It is important to consider these features in earthquake hazard assessments in southwestern Africa and other similar areas around the world. Key Points: Four major neotectonic normal faults are identified in a small area of SW NamibiaScarps show evidence of repeated brittle reactivation of ancient ductile structures in large earthquakesExceptional preservation may be responsible for the unexpected density of observable paleoseismic ruptures in the area [ABSTRACT FROM AUTHOR]

This study explores the geomorphological expression and geological context of a normal fault scarp in a stable continental region (SCR) which we interpret as having failed in large (M w >7) earthquakes. Records of such large normal faulting events in an SCR (or even in more rapidly deforming regions) are extremely rare, and so understanding this feature is of international interest. The scarp is exceptionally well-preserved due to the extensive calcrete/silcrete cementation. In areas where this cementation is reduced or absent the scarp is more diffuse, as expected for a feature formed by one or more paleoearthquakes. The exceptional preservation aids comparison with data sets based on scarps which have formed more recently. Our analysis is based on a high-resolution digital elevation model of the Hebron Fault scarp in southern Namibia using pan-sharpened Worldview-3 satellite stereophotos (0.31 m resolution). We make scarp height measurements at 160 locations providing improved estimates of the average displacement (5.9 m), maximum displacement (10.1 m), and the minimum fault length (45 km). No consistent evidence of lateral displacements in water courses or alluvial fan margins were found implying predominantly normal displacement. A newly described section in the northwest has en-echelon scarps consistent with a component of strike-slip motion that may be explained by its difference in strike from the central section. Most channels crossing the fault show a single knick-point. The displacement varies smoothly as it crosses a number of different generations of alluvial fan surfaces. No evidence of a multiscarp or a composite scarp were observed. We have therefore found no evidence for a mutiple-event origin for the scarp, although, this lack of evidence does not conclusively demonstrate a single-event origin. Published regressions, based on the limited data available for SCRs, suggest that the mean expected average displacement (⁠|$\bar{D}_{\rm av}$|⁠) for a faults of this length is 1.2–3.1 m implying that the scarp is likely to have formed in 2–5 events with an expected Mw = ∼7.1 though displacements in individual events may exceed these average values. Comparison with the regional geology and aeromagnetic data sets suggests that the fault reactivates a Mesoproterozoic ductile structure, the Nam Shear Zone, and that the location, orientation and segmentation of the scarp is controlled by the alignment of pre-existing structurally weak zones with the present-day stress regime. The fault has undergone repeated brittle reactivation, accumulating ∼110 m of vertical offset since the deposition of the Ediacaran-to-Cambrian Nama Group. This is less than expected from global compilations of total displacement and fault length data, suggesting that the fault rapidly attained its current length by recruiting an existing weak zone and is expected to accumulate displacement at a relatively constant length in the future. [ABSTRACT FROM AUTHOR]

The Bilila‐Mtakataka Fault (BMF), at the southern end of the western branch of the East African Rift System (EARS), has been used in various scaling relation studies and arguments about the strength of the lithosphere. We present evidence for a similar, though more degraded, frontal scarp on the graben‐bounding synthetic Chirobwe‐Ntcheu Fault (CNF), showing that this fault is active simultaneously with the BMF. We deployed 17 geophones for ∼60 days around the southern end of Lake Malawi, across the footwall and hangingwall of the BMF. Continuous microseismicity can be seen from the surface to ∼35 km depth highlighting a plane dipping ∼42°E. Lower‐crustal earthquakes have previously been found in the EARS, and based on location and focal mechanism have been hypothesized to occur on planes that line up with the surface traces of large faults. However, no previous study of the EARS has revealed a fault plane throughout the crust that shows seismicity along its full length from the surface to the base of the crust. Rather, the lack of seismicity seen at mid‐lower crustal depths, has led some people to the "jelly sandwich" hypothesis. Our results show that the entire crust is seismogenic, so support the "crème brûlée" model. In our two month deployment we recorded 22 aftershocks ML ≥ 2 from the March 8th, 2018 earthquake 200 km south of our array, 7 months after the mainshock, confirming that aftershock sequences in regions of low strain have a long duration, and could be the main component of seismicity in slowly straining regions. Plain Language Summary: We set out instruments around the southern end of Lake Malawi to detect earthquakes. There is a large fault in the area, the Bilila‐Mtakataka Fault, where a large earthquake has occurred previously. Evidence for this comes from a ∼110 km‐long cliff, averaging 14 m high, showing movement in a past earthquake, which probably happened thousands of years ago. We found a ∼80 km‐long cliff at the base of another large nearby fault, called the Chirobwe‐Ntcheu Fault. This means that large earthquakes could also occur on this fault. There was no previous evidence for what these faults looked like beneath the surface, or whether many small earthquakes were happening on it. We discovered that these faults are probably a continuous straight line underground, highlighted by small earthquakes that occur from the surface to almost 35 km depth. This shows that a very large earthquakes could occur, reaching from this large depth all the way to the surface. We recorded, in 2 months, 40 events from the coal fields at Tete, Mozambique, where previously residents have complained that coal blasting creates shaking and has formed cracks in their homes. The events that we detected are the likely cause of these cracks. Key Points: Microseismicity occurs throughout the entire crust in southern MalawiMicroseismicity highlights a normal fault plane all the way down to 35 kmThe entire crust is capable of hosting earthquakes (i.e., not the jelly sandwich model) [ABSTRACT FROM AUTHOR]

This article focuses on Bretherton's treatment of Pentecostalism and Black Power and how they conceive and challenge notions of democracy, citizenship and capitalism. Recognising the 'tensional' relationship between democracy and Christianity, I explore his treatment of Pentecostalism and capitalism. I am sympathetic to Bretherton's analysis of the socio-political transformation Pentecostalism offers, but point to regressive influences associated with the 'prosperity gospel'. Relating his treatment of Black Power to the wider 'Black radical tradition', I conclude with reference to political activism in the UK. [ABSTRACT FROM AUTHOR]

Despite the success of combination anti-retroviral therapy (cART), around 50% of HIV-infected individuals still display a variety of neuropathological and neurocognitive sequelae known as NeuroHIV. Current research suggests these effects are mediated by long-term changes in CNS function in response to chronic infection and inflammation, and not solely due to active viral replication. In the post-cART era, drug abuse is a major risk-factor for the development of NeuroHIV, and increases extracellular dopamine in the CNS. Our lab has previously shown that dopamine can increase HIV infection of primary human macrophages and increase the production of inflammatory cytokines, suggesting that elevated dopamine could enhance the development of HIV-associated neuropathology. However, the precise mechanism(s) by which elevated dopamine could exacerbate NeuroHIV, particularly in chronically-infected, virally suppressed individuals remain unclear. To determine the connection between dopaminergic alterations and HIV-associated neuroinflammation, we have examined the impact of dopamine exposure on macrophages from healthy and virally suppressed, chronically infected HIV patients. Our data show that dopamine treatment of human macrophages isolated from healthy and cART-treated donors promotes production of inflammatory mediators including IL-1β, IL-6, IL-18, CCL2, CXCL8, CXCL9, and CXCL10. Furthermore, in healthy individuals, dopamine-mediated modulation of specific cytokines is correlated with macrophage expression of dopamine-receptor transcripts, particularly DRD5, the most highly-expressed dopamine-receptor subtype. Overall, these data will provide more understanding of the role of dopamine in the development of NeuroHIV, and may suggest new molecules or pathways that can be useful as therapeutic targets during HIV infection. [ABSTRACT FROM AUTHOR]

The summit region of Ben Nevis, Britain's highest mountain, consists of late Silurian to Early Devonian age volcanic rocks originally interpreted as a thick sequence (> 600 m) of andesite lavas and agglomerates that were down‐faulted during caldera subsidence. New digital field mapping of the Ben Nevis area, including both the steep north and south faces of the mountain, has revealed that the volcanic rocks consist largely of volcaniclastic debris flows, and extensive block and ash flow deposits with minor air‐fall tuff units. There is no evidence of any andesite lava flows or a volcanic vent. The volcanic detritus was derived from a volcanic centre situated to the NW of Ben Nevis, perhaps several tens of kilometres away. The rocks forming the summit region of the mountain have been re‐interpreted as a large roof pendant or keel of the former late Silurian to Early Devonian volcanic land surface that once covered much of the SW Highlands of Scotland. [ABSTRACT FROM AUTHOR]

Caledonian postorogenic magmatic processes are not well understood. New digital mapping and three-dimensional modeling of the end-Caledonian (late Silurian to Early Devonian) Ben Nevis Igneous Complex in the SW Highlands of Scotland provide quantitative estimates ofmagmatic rock volumes for the first time and argue against local sources for the volcanic rocks or caldera interpretations for structural evolution. Reexamination of the Ben Nevis Intrusive Ring Tuff, key evidence for caldera collapse, shows it to be a restricted marginal facies of the trondhjemitic InnerGranite, and there is no evidence for a ring fault, previously argued as evidence for cauldron subsidence. The volcanic rocks at the core of the complex appear to form a 1.3-km3 roof pendant in the Inner Granite, and paleoflow evidence suggests that they had a distal volcanic source to the NW. Compositional comparisons between the InnerGranite and themonzonitic Outer Granite indicate that they are unlikely to have had a common petrogenesis or be coeval. The plutonic rocks form a concentric, composite, 6.4 × 8.5-km tabular body, elliptical in plan, with a total volume in the range 44-105 km3. Large areas of late Precambrian Dalradian Supergroup metasedimentary country rocks form parts of a steeply dipping carapace and roof pendants at the edge of the complex. Comparisonwith calc-alkaline volcanic rocks and plutons of the comparable Cenozoic San Juan Volcanic Complex in Colorado suggests that the plutonic rocks may have grown as laccoliths during regional caldera volcanism. Structural data suggest that the laccoliths inflated toward the SE, fed by NE-SWdikes in the core of the tightly folded Appin Syncline. This reevaluation of a classic area of world geology sheds light on a lost volcanic landscape that once covered much of the SW Highlands of Scotland. [ABSTRACT FROM AUTHOR]

The Jurassic - Cretaceous Kirkwood Formation forms part of the Uitenhage Group, the earliest deposits to fill Mesozoic rift basins that developed in what is now the southern Cape of South Africa during the breakup of Gondwana. The Kirkwood Formation is not only palaeontologically extremely important, having yielded diverse assemblages of vertebrate, invertebrate and plant fossil taxa, but also contains suitable source rocks for hydrocarbon systems offshore of the southern Cape of South Africa. The Kirkwood Formation comprises chronostratigraphic markers in the form of radiometrically dateable volcaniclastic deposits and age-diagnostic invertebrate fossils, which may provide robust dates for the depositional history of the Uitenhage Group. The Kirkwood, including the Bethelsdorp, Colchester and Swartkops Members, is 2210 m at its thickest and comprises sandstones and mudstones deposited in fluvial and lacustrine depositional settings from the Tithonian to Valanginian. These microfossil-based ages may only apply to the unit in its type area in the Algoa Basin and not to its lithostratigraphic correlatives in the otherMesozoic rift basins, which have highly variable ages ranging fromMiddle Jurassic to Early Cretaceous. [ABSTRACT FROM AUTHOR]

The Uitenhage Group represents the earliest deposits that filled Mesozoic rift basins in the southern Cape of South Africa during the fragmentation of the supercontinent Gondwana. The sedimentology of the Enon Formation records the development of alluvial systems that drained the region since the onset of Gondwanan rifting, and therefore plays an important role in our understanding of early landscape evolution along the southern African continental margin. The mostly coarse conglomeratic unit was deposited continuously in actively subsiding, but separated, rift basins. As a result, the deposits are diachronous between basins and display highly varied thicknesses of up towell over 2000 m. [ABSTRACT FROM AUTHOR]

A novel high-resolution planar and portable differential mobility analyzer (DMA) has been designed and built (Nano-ID® PMC500, Naneum, Canterbury, UK). Finite element multi-physics numerical modeling was employed to optimize the geometry of the DMA and to find a regime for high resolution within the confines of a portable instrument. The numerical approach for solving the Navier–Stokes equation was verified by comparison of calculated data to experimental values. The PMC500 was calibrated and tested with different monodisperse aerosol challenges. The PMC500 portable DMA is shown to have good sizing accuracy and resolution, similar in performance to commercially available desktop instruments. Copyright 2014 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

Health risks associated with the inhalation of airborne particles are known to be influenced by particle size. Studies have shown that certain nanoparticles, with diameters <100 nm, have increased toxicity relative to larger particles of the same substance. A reliable, size-resolving sampler able to collect a wide range of particle sizes, including particles with sizes in the nanometre range, would be beneficial in investigating health risks associated with the inhalation of airborne particles. A review of current aerosol samplers used for size-resolved collection of airborne particles highlighted a number of limitations. These could be overcome by combining an inertial deposition impactor with a diffusion collector in a single device. Verified theories of diffusion and inertial deposition suggested an optimal design and operational regime. The instrument was designed for analysing mass distribution functions. Calibration was carried out using a number of recognized techniques. The sampler was tested in the field by collecting size-resolved samples of lead containing aerosols present at workplaces in factories producing crystal glass. The mass deposited on each screen proved sufficient to be detected and measured by an appropriate analytical technique. Mass concentration distribution functions of lead were produced. The nanofraction of lead in air varied from 10 to 70% by weight of total lead. [ABSTRACT FROM PUBLISHER]

A literary criticism of the book "The Rise and Demise of Black Theology" by Alistair Kee is presented. It examines the content and challenges of Kee's contentious claims concerning the failure of Black Theology and its repeated mantras. It intends to make a few remarks about the implications of politicization and the hermeneutical circle of black theology.

Flight activity of Phorodon humuli was monitored using suction traps, laboratory studies and mark and recapture experiments. Emigrants were trapped as they flew from a Myrobalan ( Prunus cerasifera) hedge and among dwarf hops ( Humulus lupulus). Daily flight curves were bimodal with 69% and 38% of emigrants caught in the morning peak near Myrobalan and among hops, respectively. The median period of flight activity was from 2 h after sunrise until 30 min before sunset. The lower temperature for flight was 13.5°C in the field and 14.9°C for take off in the laboratory. Variations in wind speed had little effect on flight activity explaining <2.5% of the total variance among insect counts. The percentage of emigrants on hop declined exponentially with time. The relationship, y= 10.9(±2.0) + 64.3(±2.3) × 0.92(±0.01) t where t = daylight hours (standard error in parentheses), explained 98.3% of the variance. Hence, 62% of new arrivals flew within 1 day of arrival and 79% within 2 days. Similar numbers arrived as departed at 08:30, 10:30 and 12:30 h, but at 14:30 h twice as many arrived than departed and at 16:30 h, the accumulation was threefold. Daily flight curves of return migrants and males leaving hop were bimodal with 70% and 80%, respectively, trapped in the earlier peak. In the field, the median lower temperature for flight was 13.2°C for return migrants and a nonsignificantly different 12.8°C for males. The mean temperature for take off by return migrants was 15.7°C in the laboratory. [ABSTRACT FROM AUTHOR]

Examines the transition of the Black Christian community in Europe. Influence of martyr Stephen Lawrence on the Black Christian community; Impact of the death of Lawrence on Black Christians; Definition of racism experienced by the black church; Role of the black church on the European political and social structures.

Diffusible auxin levels were measured in coleoptiles and mesocotyls of dark-grown seedlings of avena sativa (cv. Spear) and Zea mays (cv. Golden Cross Bantam) using the Avena curvature bioassay. The coleoptile tip was confirmed as the major auxin source in etiolated seedlings. Auxin levels were found to decrease basipetally in sequent sections of the Avena coleoptile but not to decrease in apical sections of increasing length. An inhibitor capable of inducing positive curvatures of Avena test coleoptiles was discovered in diffusates from the mesocotyls of oat and corn seedlings. The amount of this inhibitor was correlated with the cessation of mesocotyl growth of oat seedlings grown in darkness, and with the inhibition of mesocotyl growth of corn seedlings exposed to red light. [ABSTRACT FROM AUTHOR]

Presents several letters related to medicine in Great Britain. Reluctance of politicians to invest heavily on health services; Contributions of physician Thomas Sydenham on medical teaching; Allocation of resources or rationing by an elected government.

Presents a report on Laurentian clasts in a Neoproterozoic tillite from Scotland, with focus on geology. Description the provenance of the Port Askaig tillite in order to test recent plate geotectonic models; What is the juvenile nature of the source granites; Reference made to paleoproterozoic crustal growth.

Corticomotor (CM) neurones were identified in three conscious macaque monkeys by the presence of post-spike facilitation (PSF) in spike-triggered averages of e.m.g. recorded from intrinsic hand and forearm muscles during performance of a precision grip task. Post-spike effects were compared with those produced by single-pulse intracortical microstimulation (ICMS), with strengths of 4-20 μA, delivered at the site of 47 CM cells. Most muscles facilitated by a CM cell were also facilitated by ICMS at the site of the cell. ICMS effects were stronger: at 10 μA, the amplitude of ICMS-evoked facilitation was on average 2.8 times greater than PSF, and 6.9 times greater at 20 μA. Onset latency of ICMS-evoked facilitation was consistently longer (by 1.7 and 1.3 ms at 10 and 20 μA respectively) than PSF, and it is suggested that this results from the indirect, trans-synaptic excitation of CM cells by ICMS. Post-spike suppression was rarely seen (7/421 compared to 105/421 cases of PSF). In contrast, suppression and facilitation were equally common in response to ICMS. The synaptic mechanisms underlying these effects were explored in 5 anaesthetised macaque monkeys. ICMS facilitated a greater proportion of the tested muscles than did the CM cell recorded at the stimulus site. The results suggest the juxtaposition in the motor cortex of CM neurones with different 'muscle fields'. The merits of STA and ICMS for exploring cortical organisation are discussed. [ABSTRACT FROM AUTHOR]

In cat the existence of collaterals from deep cerebellar neurons, which project to mesencephalon and thalamus has been investigated anatomically by means of the multiple retrograde fluorescent tracer technique as well as electrophysiologically by means of conventional antidromic techniques. Both sets of data indicate that several neurons in the medial nucleus, which project to mesencephalon and thalamus, also distribute collaterals to medulla oblongata and spinal cord. These branching neurons were principally located in the caudal and intermediate portions of the medial nucleus. The electrophysiological data in addition indicate that the branching point of the neurons in the medial nucleus is located relatively close to the cell soma. The anatomical findings show a further group of branching neurons in the lateral nucleus at the border with the interpositus nuclei. The majority of these latter neurons distribute collaterals to medulla oblongata but some distribute collaterals to spinal cord. However, it could not be decided as yet whether the collaterals to the medulla oblongata terminate either in medullary medial reticular formation or in inferior olive or in both. [ABSTRACT FROM AUTHOR]

Fifty-one strains recently isolated from cases of bovine mastitis have been studied in their morphological, cultural and biochemical reactions.Using their colony appearance in blood agar as the first differential criterion we have shown that the strains differ widely from one another and from the α β and γ streptococci usually encountered in human disease.The heterogeneity of mastitis streptococci was strikingly demonstrated. From the results of a relatively small number of cultural and biochemical tests it could be shown that no two of the fifty-one strains were identical, in every respect.The findings recorded suggest that great caution must be exercised in ascribing a bovine or human origin to individual strains of streptococci on the results of cultural or biochemical reactions. [ABSTRACT FROM PUBLISHER]