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Billingham UK, where Mike Spencer spent his entire industrial career, has long been associated with the use of steam reforming for the production of synthesis gas required for the manufacture of some important chemicals, particularly ammonia and methanol. This paper describes the steam reforming process and presents some of the history of the development of tubular reforming. The catalysts, technology and industrial operation of plants are briefly reviewed. Newer technologies, such as adiabatic reforming, autothermal reforming (ATR) and gas heated reforming (GHR) that aim to increase efficiency of and reduce the environmental impact of conventional steam reforming processes are presented.

As the human population continues to grow, so too do the concerns regarding the sustainability of waste management from our food production systems. Faced with limited environmental resources for food production, issues related to food loss and waste are critical in mitigating challenges stemming from projected population growth and long-term food security and sustainability. The potential for using insects to consume organic waste materials and convert them into feed for animal, biofuels, and other valuable secondary products is gaining momentum as both a research discipline and as a business opportunity. Here, this ecosystem service is referred to as “insects as bioconverters of organic waste.” Scientific reviews of this topic have mainly focused on the challenges associated with development of commercial scale systems. To compliment existing reviews, we address this exciting topic from an artificial selection perspective, as we review and discuss aspects associated with targeted breeding and adaptation of both gut microbial communities and host insects themselves. We describe the “ideal insect bioconverter,” insects uniquely equipped to convert wastes into biomass and other valuable secondary products, and we present the current knowledge and existing research gaps towards the development of such organisms. We conclude that (1) targeted breeding of insects and their gut microbes can produce tailored insect lineages for bioconversion of specific waste streams; (2) research is needed to take full advantage of the existing insect diversity to identify new candidate species for bioconversion; and (3) further research into insect-gut microbial complexes will likely provide important insight into ways insects can be used as sustainable bioconverters of highly specialized waste streams.

Modeling oviposition as a function of female insect age, temperature, and host plant suitability may provide valuable insight into insect population growth of polyphagous insect pests at a landscape level. In this study, we quantified oviposition by beet leafhoppers, Circulifer (= Neoaliturus ) tenellus (Baker) (Hemiptera: Cicadellidae), on four common non-agricultural host plant species [ Erodium cicutarium (L.) L’Hér. (Geraniaceae), Kochia scoparia (L.) Schrader (Amaranthaceae), Plantago ovata Forsskál (Plantaginaceae), and Salsola tragus L. (Amaranthaceae)] at two constant temperature conditions. Additionally, temperature-based oviposition models for each host plant species were validated, under semi-field and greenhouse conditions. We found that K . scoparia was the most suitable host plant, and optimal temperature for oviposition was estimated to be 30.6°C. Accordingly, beet leafhoppers appear to be well-adapted to high-temperature conditions, so increasing temperatures due to climate change may favor population growth in non-agricultural areas. Maximum total fecundity ( R m ) was used as an indicator of relative suitability of host plants. S . tragus has been considered an important non-agricultural host plant, however, we found that S . tragus and E . cicutarium have lower R m compared to K . scoparia and P . ovata . The combination of detailed experimental oviposition bioassays, modeling, and model validation is considered widely relevant and applicable to host plant assessments and modeling of population dynamics of other polyphagous insect pests.

There is widespread evidence of plant viruses manipulating behavior of their insect vectors as a strategy to maximize infection of plants. Often, plant viruses and their insect vectors have multiple potential host plant species, and these may not overlap entirely. Moreover, insect vectors may not prefer plant species to which plant viruses are well-adapted. In such cases, can plant viruses manipulate their insect vectors to preferentially feed and oviposit on plant species, which are suitable for viral propagation but less suitable for themselves? To address this question, we conducted dual- and no-choice feeding studies (number and duration of probing events) and oviposition studies with non-viruliferous and viruliferous [carrying beet curly top virus (BCTV)] beet leafhoppers [ Circulifer tenellus (Baker)] on three plant species: barley ( Hordeum vulgare L.), ribwort plantain ( Plantago lanceolata L.), and tomato ( Solanum lycopersicum L.). Barley is not a host of BCTV, whereas ribwort plantain and tomato are susceptible to BCTV infection and develop a symptomless infection and severe curly top symptoms, respectively. Ribwort plantain plants can be used to maintain beet leafhopper colonies for multiple generations (suitable), whereas tomato plants cannot be used to maintain beet leafhopper colonies (unsuitable). Based on dual- and no-choice experiments, we demonstrated that BCTV appears to manipulate probing preference and behavior by beet leafhoppers, whereas there was no significant difference in oviposition preference. Simulation modeling predicted that BCTV infection rates would to be higher in tomato fields with barley compared with ribwort plantain as a trap crop. Simulation model results supported the hypothesis that manipulation of probing preference and behavior may increase BCTV infection in tomato fields. Results presented were based on the BCTV-beet leafhopper pathosystem, but the approach taken (combination of experimental studies with complementary simulation modeling) is widely applicable and relevant to other insect-vectored plant pathogen systems involving multiple plant species.

This article traces the life and death of two wolves that perished at the hands of 18th-century settlers in the small agropastoral community of San Antonio del Embudo in what is today northern New Mexico. Through a study of their interred remains, we examine how wolves became entangled in the unfolding negotiations between settler and Indigenous communities in the American West, playing varied ecological, political, and symbolic roles. In the process, we advance two wider arguments: first, that the archaeology of settler colonialism would do well to adopt a multispecies perspective in which nonhuman animals are counted among both the colonizers and the colonized, and second, that doing so requires a new mode of historical narration focused on the experiences of individual nonhumans as opposed to the anonymous, animalistic mass.

Past discussions of Eastern Pueblo moiety organization in the American Southwest have been dominated by structural-functionalist positions and have proposed that moieties emerged in this area in order to facilitate the social integration of large, aggregated villages. This paper revisits the question of moiety origins from an archaeological perspective, presenting new data from the ancestral Northern Tiwa region that document the presence of a dual division as early as the late thirteenth century at the large village of T'aitöna (Pot Creek Pueblo). Consideration of the village's position within the local historical trajectory suggests that moieties were initially established there as a means of formalizing the social relationships between a local population and a recently arrived group of immigrants. The paper ends by arguing that these sorts of specific historical phenomena must be granted greater causal significance in the explanation of Eastern Pueblo moiety origins.

This paper investigates the material construction of Pueblo cosmology in the northern Rio Grande during and following the emergence of large aggregated villages at the end of the thirteenth century A.D. My central claim is that villages and the landscapes that surrounded them were mutually constitutive and need to be viewed holistically as components of integrated villagescapes that linked the dwellings of the living to the dwellings of ancestral spirits, and the social order of the village to the spatial order of the cosmos. \"Village aggregation,\" in this sense, emerges as a misnomer given the radical geographic extension of ritual practice and constructed space that went hand-in-hand with residential agglomeration. I begin by synthesizing ethnographic evidence of Tewa and Northern Tiwa sacred geographies, paying close attention to the distribution and interpretation of archaeologically visible shrine features. I then use this ethnographic understanding as a basis for interpreting the archaeological evidence of the extensive complex of shrine features surrounding T'aitöna (Pot Creek Pueblo), one of the northern Rio Grande's earliest large villages.

As was the case throughout much of north-central New Mexico, the late twelfth and thirteenth centuries marked a period of rapid settlement pattern change in the Taos District as dispersed pithouse and small pueblo hamlets were replaced by tightly clustered pueblos and ultimately by the emergence of large aggregated villages. Here we consider the effects of this transition on the manner in which local potters procured raw clay for the production of black-on-white ceramics. Adopting the Rio Grande del Rancho drainage as our study area, we first outline the major clay sources within the drainage. We then report on neutron activation and petrographic analyses of both modern clays as well as archaeological ceramics from sites that span the settlement transition in question. These analyses suggest that settlement aggregation was accompanied by a noticeable reduction in the diversity and quality of clay sources used by local potters, most likely as a result of newly restricted procurement strategies associated with the formation of buffer zones between village aggregates. The paper concludes with a consideration of the implications of this trend with respect to the economic situation of early large villages in the area.

Background While both preclinical and clinical studies suggest that the frequency of growing skeletal metastases is elevated in individuals with higher bone turnover, it is unclear whether this is a result of increased numbers of tumour cells arriving in active sites or of higher numbers of tumour cells being induced to divide by the bone micro-environment. Here we have investigated how the differences in bone turnover affect seeding of tumour cells and/or development of overt osteolytic bone metastasis using in vivo models of hormone-independent breast and prostate cancer. Methods Cohorts of 6 (young) and 16 (mature)-week old BALB/c nude mice were culled 1, 7 and 21 days after received intracardiac injection of luciferase expressing human prostate (PC3) or breast cancer (MDA-MB-231) cell lines labelled with a fluorescent cell membrane dye (Vybrant DiD). The presence of growing bone metastases was determined by bioluminescence using an in vivo imaging system (IVIS) and followed by anatomical confirmation of tumour metastatic sites post mortem, while the presence of individual fluorescently labelled tumour cells was evaluated using two-photon microscopy ex vivo . The bone remodelling activities were compared between young and mature naïve mice (both male and female) using micro-CT analysis, ELISA and bone histomorphometry. Results Both prostate and breast cancer cells generated higher numbers of overt skeletal lesions in young mice (~80%) than in mature mice (~20%). Although mature mice presented with fewer overt bone metastases, the number of tumour cells arriving/colonizing in the tibias was comparable between young and mature animals. Young naïve mice had lower bone volume but higher bone formation and resorption activities compared to mature animals. Conclusions Our studies suggest that higher frequencies of growing osteolytic skeletal metastases in these models are linked to increased bone turnover and not to the initial number of tumour cells entering the bone microenvironment.