Effect of Burner Wall Material on Microjet Hydrogen Diffusion Flames near Extinction: A Numerical Study

Characteristics of microjet hydrogen diffusion flames stabilized near extinction are investigated numerically. Two-dimensional simulations are carried out using a detailed reaction mechanism. The effect of burner wall material, thickness, and thermal radiation on flame characteristics such as flame height and maximum flame temperature are studied. Results show that the flame stabilizes at lower fuel jet velocities for quartz burner than steel or aluminum. Higher flame temperatures are observed for low conductive burners, whereas the flame length increases with an increase in thermal conductivity of the burner. Even though thermal radiation has a minor effect on flame characteristics like flame temperature and flame height, it significantly influences the flame structure for low conductive burner materials. The burner tip and its vicinity are substantially heated for low conductive burners. The effect of burner wall thickness on flame height is significant, whereas it has a more negligible effect on maximum flame temperature. Variation in wall thickness also affects the distribution of H and HO2 radicals in the flame region. Although the variation in wall thickness has the least effect on the overall flame shape and temperature distribution, the structure near the burner port differs.

The Sustainability of Bison Production in North America: A Scoping Review

The American bison (Bison bison) is iconic of the Great Plains of North America, yet the genus has had to overcome near extinction in the recent past prior to being re-established for food production. This scoping review summarizes the literature on the Plains Bison as a large ruminant species adequate for modern-day meat production in order to evaluate the species’ appropriateness as a sustainable meat source and to identify knowledge gaps hindering the sustainability evaluation of bison production. To date, we can anecdotally assume that bison husbandry could contribute to sustainability based on its positive contribution to biodiversity, physiological robustness, economically higher price per kg, and nutritive values, despite their decreased growth and performance rates compared to beef cattle. However, targeted and system-based research is required in order to unequivocally assess the sustainability of bison production in North America.

Ancient mitogenomes unravel massive genetic diversity loss during near extinction of Alpine ibex

Population bottlenecks can have dramatic consequences for the health and long-term survival of a species. A recent bottleneck event can also largely obscure our understanding of standing variation prior to the contraction. Historic population sizes can be modeled based on extant genomics, however uncertainty increases with the severity of the bottleneck. Integrating ancient genomes provides a powerful complement to retrace the evolution of genetic diversity through population fluctuations. Here, we recover 15 high-quality mitogenomes of the once nearly extinct Alpine ibex spanning 8601 BP to 1919 CE and combine these with 60 published modern genomes. Coalescent demography simulations based on modern genomes indicate population fluctuations matching major climatic change over the past millennia. Using ancient genomes, we show that mitochondrial haplotype diversity has been reduced to a fifth of the pre-bottleneck diversity with several highly differentiated mitochondrial lineages having co-existed historically. The main collapse of mitochondrial diversity coincided with human settlement expansions in the Middle Ages. The near extinction severely reduced the mitochondrial diversity. After recovery, one lineage was spread and nearly fixed across the Alps due to recolonization efforts. Contrary to expectations, we show that a second ancestral mitochondrial lineage has survived in an isolated population further south. Our study highlights that a combined approach integrating genomic data of ancient, historic and extant populations unravels major long-term population fluctuations.

Language Attrition and its Impact on Culture – A Case of Saraiki in Dera Ghazi Khan Region

Language attrition is primarily the loss of language and subsequently the loss of culture and identity. A number of languages have become extinct, and many languages of the world are near extinction. This study analyzes the impact of language attrition on Saraiki and its culture in the D. G. Khan region. This research takes into consideration two domains of language use: home and university. Paradis's (2004) Activated Threshold Hypothesis (ATH) supplemented with Bot, Lowie & Verspoor's (2007) Dynamic Systems Theory (DST) has been adopted as a theoretical framework. The mixed-method approach has been used, and a sample of 100 respondents was selected from the target population. The respondents were instructed to define certain Saraiki vocabulary items, and their responses were recorded. The findings show that socio-economic, socio-cultural, socio-political and socio-demographic factors are responsible for the language attrition of Saraiki and the subsequent impact on the culture of the speakers in the selected locale.

Sarcoptic mange outbreak decimates South American camelid populations in San Guillermo National Park, Argentina

Sarcoptic mange epidemics can devastate wildlife populations. In 2014, mange was first detected in vicuña ( Vicugna vicugna ) and guanaco ( Lama guanicoe ) in San Guillermo National Park (SGNP), Argentina. This study characterized the potential source and the impacts of the outbreak in 2017–2019. Transect surveys indicated a sharp decrease in the density of live vicuña and guanaco by 68% and 77%, respectively, from May 2017 to June 2018. By April 2019 no vicuña or guanaco were recorded on transect surveys, suggesting a near-extinction at the local level. Clinical signs consistent with mange (e.g. intense pruritus, hyperkeratosis, alopecia) were observed in 24% of live vicuña (n = 478) and 33% of live guanaco (n = 12) during surveys, as well as in 94% of vicuña carcasses (n = 124) and 85% of guanaco carcasses (n = 20) opportunistically examined during the study period. Histological examination (n = 15) confirmed sarcoptic mange as the cause of the cutaneous lesions. Genetic characterization revealed that Sarcoptes scabiei recovered from seven vicuña (n­ = 13) and three guanaco (n = 11) shared the same genotype, which is consistent with a single source and recent origin of the epidemic. A governmental livestock incentive program introduced llama ( Lama glama ) in areas adjacent to SGNP in 2009, some of which reportedly had alopecic scaling consistent with sarcoptic mange. We hypothesize that the introduction of mange-infected llama may have triggered the outbreak in wild camelids which has now put them at a high risk of local extinction. This unprecedented event highlights that the accidental introduction of disease may be underestimated at the onset yet can have devastating effects on native ungulate populations with potentially profound effects at the community and ecosystem levels.

Modelling stakeholder satisfaction for conflict resolution in wildlife management: a case of wolf population in Sweden

The Swedish wolf population has rebounded from near extinction in the 1960s to around 365 individuals in 2020, after the implementation of the Hunting Act (jaktlagen) in 1966. This recent increase in the wolf population has evoked a serious divide between “pro-wolf” and “anti-wolf” Swedish citizens. Despite the continuous efforts by the Swedish government to reconcile this antagonism, the conflicts are persistent with a sign of impasse. In this paper, we present a modelling tool, which can bring transparent and “structured dialogue to the opposing positions.” This approach includes a stylized framework for quantitative modelling of stakeholders’ satisfaction levels regarding their preferred size of the wildlife population in question, based on the concept of satisfaction functions. We argue that this framework may contribute to conflict resolution by bringing a common understanding among stakeholders, facilitate a societal discourse, and potentially help to assess likely support for conservation policies. We present a showcase application of this modeling tool in the context of the conflict over the Swedish wolf conservation policies. The model is informed using a thorough literature review as well as interviews, which identified relevant stakeholder groups and respective drivers of their attitudes towards wolves.

Neither stable nor pristine: American bison populations were long influenced by humans

Populations of North American bison (Bison bison) are widely presumed to have remained stable, numbering in the tens of millions, right up until the hide hunts of the 1870s nearly brought about extinction. Recent scholarship from various disciplines consistently undermines this presumption. Indigenous people likely affected bison populations from their arrival toward the end of the Pleistocene. By the time of Columbus, indigenous populations were high and their impacts were felt keenly. As documented in the 16th century journals of Cabeza de Vaca, big game populations, including bison, were suppressed by hunting. That changed, however, with arrival of Old World diseases that are estimated to have reduced indigenous populations in the Americas by 90 % within a century of contact with Europeans. Such drastic reductions in indigenous human populations allowed bison populations to expand. Gradually, increased pressure from human hunters, along with competition from feral horses, introduced infectious diseases, habitat changes, and droughts, all suppressed bison populations well before the notorious hide hunts began in the 1870s. The hide hunts were the final blow to free-ranging bison, but reduced populations in the decades prior paved the way and helps explain why bison were reduced to near extinction within a few years.

Be that as it may: The Unremarkable Trajectory of the English Subjunctive in North American Speech

The English subjunctive has had a checkered history, ranging from extensive use in Old English to near extinction by Late Modern English. Since then, the mandative variant was reported to have revived, while the adverbial subjunctive continued to diminish. American English is heavily implicated in these developments; it is thought to be leading the revival of the former but lagging in the decline of the latter. Observing that most references to these changes are based on the written language, we examine the diachronic trajectory of the subjunctive in North American English speech. Adopting a variationist perspective, we carried out systematic quantitative analyses of subjunctive use under hundreds of triggers. Results show that, despite the differences in their diachronic trajectories, today both types are not only extremely rare but heavily lexically constrained. We implicate violations of the Principle of Accountability in the disparities between the findings reported here and the consensus in the literature with respect to subjunctive use in North American English.

Károly Pál Pálffy and the Dear “Familia”

The Pálffys were among the wealthiest and most influential families in the Kingdom of Hungary and the Habsburg Monarchy. The family owed its arrival in the political, economic, and social elite to Miklós Pálffy (1552–1600), the “hero of Győr.” His descendants obtained the highest offices in Hungary—Pál Pálffy (1592–1653) became chief justice and palatine—and filled important positions in the Imperial Court in Vienna (Pál Pálffy became a member of the Privy Council). In the first half of the eighteenth century, the Pálffys excelled primarily in military service; however, multiple wars led to the near extinction of the male branch of the family as numerous young Pálffy men lost their lives on the battlefield. Despite these serious losses, the family managed to preserve its prominent position in the Kingdom of Hungary and the Viennese court: Palatines Miklós Pálffy and János Pálffy belonged to the innermost circle of advisers to Charles III and Maria Theresa. Maintaining appearances in court, however, was enormously costly for the Pálffy family. Moreover, in the sixteenth and seventeenth centuries, the family procured their largest estates; in the eighteenth century, rather than acquiring estates, the family faced a mounting burden of debt. János Pálffy attempted to solve the problem in his will by changing the legal status of the central estate, the castle of Červený Kameň (Vöröskő, Rotenstein), to an entail (mostly referred to as Fideicommissum in European legal terminology). The result was decades of strife amongst his descendants, who did not find the entailment of Červený Kameň personally advantageous since the property could not be divided or alienated. The Pálffy family lawsuits were not unique in the eighteenth century; during the same period, the Zichys were also embroiled in family litigation. This study examines the longstanding feud that began in 1749 through the lens of family letters, providing a perspective on family history and contemporary attitudes. This study is part of wider research on the history of lawsuits and makes it possible to place the eighteenth-century legal disputes of the Hungarian nobility in a broader Central European and even European context.

Identifying sequence variation in cation channel sperm associated genes in Cape mountain zebra (Equus zebra zebra)

The Cape mountain zebra (Equus zebra zebra) has recovered from near extinction over more than eight decades. While their numbers have increased, populations remain isolated with low genetic diversity. With more than 75 new populations being founded and more than 4800 extant animals, conservation management strategies are being implemented to mitigate risk of losses in genetic diversity and reproductive fitness. One objective is to identify reproductive characteristics that may improve population growth. Cation channel sperm (CatSper) genes play an important role in hyperactivation of sperm during fertilization. Mutations in these genes lead to reduced fertility and even infertility. Ten male zebras were sampled from a group that were translocated in 2016 in order to found a new population. Single nucleotide polymorphisms (SNPs) were identified in three of the CatSper genes (1 - 3). Lack of variation was observed in all exons, with only four SNPs being identified in the intronic regions in close proximity to exons 1, 2, 7, 8, and 9 of CatSper 1. These results may contribute to the pre-identification of males for new founder populations to ensure population growth and viability, and may be a useful tool for selection against low-producing individuals.