New technologies and disruptions related to Coronavirus disease-2019 have led to expansion of decentralized approaches to clinical trials. Remote tools and methods hold promise for increasing trial efficiency and reducing burdens and barriers by facilitating participation outside of traditional clinical settings and taking studies directly to participants. The Trial Innovation Network, established in 2016 by the National Center for Advancing Clinical and Translational Science to address critical roadblocks in clinical research and accelerate the translational research process, has consulted on over 400 research study proposals to date. Its recommendations for decentralized approaches have included eConsent, participant-informed study design, remote intervention, study task reminders, social media recruitment, and return of results for participants. Some clinical trial elements have worked well when decentralized, while others, including remote recruitment and patient monitoring, need further refinement and assessment to determine their value. Partially decentralized, or “hybrid” trials, offer a first step to optimizing remote methods. Decentralized processes demonstrate potential to improve urban-rural diversity, but their impact on inclusion of racially and ethnically marginalized populations requires further study. To optimize inclusive participation in decentralized clinical trials, efforts must be made to build trust among marginalized communities, and to ensure access to remote technology.

Microprobe analyses of members of the erlichmanite-laurite series from Guma Water and Senduma, Sierra Leone and Tanah Laut, Borneo, indicate that complete solid solution is possible between OsS2 and RuS2 with considerable substitution of Os and Ru by Ir, Rh, and Pt. The cell size of the erlichmanite from Guma Water is a = 5.6183±0.0003 Å at a composition (Os0.61Ru0.30Ir0.06Rh0.03)Σ0.93S2 whilst the laurite from Senduma has a composition of (Ru0.88Os0.05Ir0.04 Rh0.03)Σ0.93S2 and a cell size of a = 5.6089±0.0005 Å. Substitution of Os for Ru provides the predominant cause of the variation of cell size. Substitution by other elements of the platinum group appears to produce little effect on cell size and is presumably controlled by genesis rather than considerations of crystal chemistry or structure. The recorded analyses for these elements indicate a pre-dominance of Ir over Rh for members of the series containing more than about 15% of the laurite molecule. For the remainder of the series Rh is more important than Ir. The reflectance in air and oil of the members of the series from Sierra Leone and Borneo are presented and the microhardness of the erlichmanite from Guma Water shown to be 1854 kg/mm2. This is the first report of laurite from Senduma, Sierra Leone.

Mathematical programming-based systems analysis is used to examine the consequences of alternative operation configuration for the agricultural operations within the Texas Department of Criminal Justice. Continuation versus elimination of the total operation as well as individual operating departments are considered. Methodology includes a firm systems operation model combined with capital budgeting and an integer programming based investment model. Results indicate the resources realize a positive return as a whole, but some enterprises are not using resources profitably. The integer investment model is found to be superior for investigating whether to continue multiple interrelated enterprises.

Decline in executive function has been noted in the prodromal stage of Alzheimer's disease (AD) and may presage more global cognitive declines. In this prospective longitudinal study, five measures of executive function were used to predict subsequent global cognitive decline in initially nondemented older adults. Of 71 participants, 15 demonstrated significant decline over a 1-year period on the Dementia Rating Scale (Mattis, 1988) and the remaining participants remained stable. In the year before decline, the decline group performed significantly worse than the no-decline group on two measures of executive function: the Color-Word Interference Test (CWIT; inhibition/switching condition) and Verbal Fluency (VF; switching condition). In contrast, decliners and non-decliners performed similarly on measures of spatial fluency (Design Fluency switching condition), spatial planning (Tower Test), and number-letter switching (Trail Making Test switching condition). Furthermore, the CWIT inhibition-switching measure significantly improved the prediction of decline and no-decline group classification beyond that of learning and memory measures. These findings suggest that some executive function measures requiring inhibition and switching provide predictive utility of subsequent global cognitive decline independent of episodic memory and may further facilitate early detection of dementia. (JINS, 2012, 18, 118–127)

Investigations into the survival and breeding of the tsetse fly Glossina morsitans Westw. in large and small cage volumes under insectary and ambient climatic conditions in the Zambezi valley, and using oxen as host animals, are described. Under ambient conditions, flies emerging from puparia collected at Kariba, and held in the insectary, survived longer than flies emerging from puparia collected at Chirundu. Flies caught from the bush did not live as long as flies emerging from puparia held in the insectary, and generally lived longer under variable than under constant climatic conditions. The survival of ‘ wild ’ flies decreased during the hot, dry months under ambient conditions. Flies lived longer and were more reproductive in small cages than in large cages. Reproduction in small cages was higher when the flies were exposed to a variable climate instead of controlled conditions, but two colonies of ‘ wild ’ flies declined under both climatic conditions. Eeproduction was better in the small, standard cages (8 × 8 × 11 in.) than in Petana boxes, while Geigy 25’s were intermediate in this respect, but survival and mean puparial weights tended to be similar. The results show a complete failure to breed G. morsitans in large cages.

Investigations, using tantalum-182, into the behaviour of Glossina morsitans Westw. in large field cages are described. Individual straight-line displacements occurred on average about every three hours and were generally small and erratic in direction. The perimeters of the cages tended to ‘ trap ’ an enclosed population, but flies appeared to move to the walls more quickly when they were shaded by an outer covering of hessian. Horizontal distribution and movements of flies did not appear to be associated directly with the enclosed vegetation, artificial roosting sites or host animals. Observations on vertical displacements indicated diurnal movements to and from boles of trees and changes in roosting heights. The majority of flies rested between six and ten feet above the ground, though individuals were seen from ground level to 30 ft. Few observations were done at night, but two flies were seen on the underside of leaves.

Laboratory and field cage trials were made with male Glossina morsitans orientalis Vanderplank treated with tepa or gamma irradiation to assess the ability of the sterile males to compete with untreated males for normal females when the ratios of treated males to untreated males to untreated females ranged from 4:1:5 to 5:2:5. Irradiation of the pupal and adult stages with 8000 and 15000 rad or 8000 and 12000 rad, respectively, reduced reproduction by 87–100% (mean, 95%). Contact for 60 min on a glass surface coated with 10 mg tepa/ft2 or exposure to 0·25 ml of 5% tepa in a wind tunnel usually produced complete sterility (mean, 99%) in 0- or 2-day-old male flies. Trials in the laboratory and in a small field cage (288 ft2) with chemosterilised flies generally reduced reproduction to near the expected values. Similar results were obtained with male flies emerging from irradiated puparia, but males treated as adults produced somewhat smaller reductions than expected. Unreplicated competitive trials with chemosterilised and irradiated males in a large field cage (8100 ft2) produced considerably smaller reductions in reproduction than expected, suggesting that treated males released in nature might not compete for normal females as readily as untreated males.

Fission-track dating of zircons and apatites from tuffs and bentonites has produced the first isotopic ages for the type sections of the Ordovician and Silurian Systems. In the Ordovician the following ages have been determined: lower Arenig 493 Ma, lower Llanvirn 487 Ma, lower Llandeilo 477 Ma, upper Caradoc 463 Ma and upper Ashgill 434 Ma. In the Silurian, the following: lower Llandovery 437 Ma, lower Wenlock 422 Ma, upper Wenlock 414 Ma and Ludlow 407 Ma. The Ordovician-Silurian boundary is interpreted as occurring at about 436 Ma. Three North American Rocklandian bentonites yielded zircons whose ages average 453 Ma. This is about 10 Ma younger than supposedly correlative units in the British type sections.

The Tremadoc Series and series of the Ordovician System are widely used in international correlations, and this review explains and summarizes how the base of each of these series is recognized in Britain. No type section in which the base of any one of them is displayed has ever been selected and formally designated, hence the basal horizon of each series is a matter of general understanding rather than precise definition. This general understanding is of particular biozones, or of assemblages of fossils and their relative ages. The geographical separation between type sections of series, and differences in facies, complicate the understanding of relative ages of biozones. Brachiopod and trilobite faunas of the Llandeilo, Caradoc and Ashgill Series have been studied in detail in recent years, and biozones proposed. These biozones have proved difficult or impossible to recognize outside their type areas in Britain, and brachiopod–trilobite faunas of the Tremadoc, Arenig and Llanvirn Series are likewise highly provincial. Thus for correlation within and outside Britain attention has been focused on the ‘standard’ graptolite biozones, particularly since such conodont faunas as have been found have not proved useful. Yet there are problems associated with these ‘standard’ biozones; for example, the Tetragraptus approximatus Biozone is unknown in Wales or England, the relationship between the base of the Glyptograptus teretiusculus Biozone and the earliest Llandeilo shelly faunas requires clarification, and at what level the base of the Caradoc Series may lie in the Nemagraptus gracilis Biozone is unknown.

Thus to bring precision to definitions of Ordovician Series in Britain the identification of continuous, fossiliferous sequences that will serve as stratotypes, is required. Such a section for the basal portion of the Tremadoc Series has recently been proposed. Systematic studies related to particular biozones are needed, for example early Caradoc and early Ashgill brachiopods, and graptolites of the Didymograptus bifidus and Glyptograptus teretiusculus Biozones. The stratigraphical ranges and abundances of species in particular sections require documentation, so that the type of biozone (assemblage, acme, concurrent-range, etc.) may be recognized. Such work could lead towards chronostratigraphy, the provision of a standard stratigraphical scale in Britain for the Tremadoc Series and Ordovician series.