bluuebunny/crossref_metadata_2025 huggingface dataset:
Identifying the 993–994 CE Miyake Event in the Oldest Dated Living Tree in Europe
Authors: Quarta Gianluca , Di Filippo Alfredo , Calcagnile Lucio , D’Elia Marisa , Biondi Franco , Saba Emanuele Presutti , Baliva Michele , De Vivo Giuseppe , Schettino Aldo , Piovesan Gianluca
Published: May 2019

Combined dendrochronology and accelerator mass spectrometry radiocarbon (AMS 14C) dating analyses were used in order to date an old living tree named Italus, growing in the Pollino massif in Southern Italy. Wiggle match AMS 14C dating analysis was performed on a 320-yr-long floating chronology obtained by cross-dating four wood cores extracted from the exposed roots of the tree. Following this approach, an age for the tree of ≈1230 yr was estimated. This age makes Italus the oldest living tree in Europe. High-resolution 14C dating analyses performed on single rings extracted from the tree stem allowed us to identify the 993–994 CE large excursion in atmospheric 14C concentration (Miyake event) revealing for the first time its presence in the Mediterranean basin.
Photographies in Africa in the digital age
Authors: Vokes Richard
Published: May 2019

In recent years, all kinds of African photographies, both on the continent and in the diaspora, have undergone a digital ‘revolution’ (Ekine and Manji 2012). Without doubt, the key driver of this trend has been the rapid, and massive, influx to practically all African countries of ever more affordable third generation/advanced mobile phone handsets, or smartphones. Even compared with earlier technological revolutions on the continent, both the speed and the scale of this spread have been simply breathtaking. For example, the establishment of transistor radio sets – the process through which personal radios became ubiquitous across Africa – occurred over the period of at least a decade and a half (between roughly the late 1950s and the early 1970s). Similarly, the original mobile phone revolution – i.e. the process through which early generation/low functionality mobile phones went from being a source of novelty, to a domain for experimentation, to technologies that were routinized in everyday life, throughout the continent – took more than a decade to unfold (the crucial years being those between roughly 1999 and 2010) (Vokes 2018b). Against both of those earlier processes, the emergence of smartphones occurred over a much shorter timeframe. Between 2011 and mid-2015 alone, the number of smartphones being imported into Africa – the majority of them sub-US$100 Android-based systems – jumped from around 10 million units per annum to almost 100 million (Tshabalala 2015), as a result of which these devices became quickly established as a common feature of everyday life. Today, more than one-third of all mobile phones in Africa are smartphones, and this percentage is set to rise to two-thirds by 2020 (GSMA Intelligence 2017).
Mobile people, phones and photography: Somali visual practices in Nairobi's Eastleigh estate
Authors: Carrier Neil
Published: May 2019

The coming of the mobile phone camera has transformed photography. This article explores this transformation through a case study of photography in Eastleigh, a Nairobi estate that is home to many thousand Somalis, both Kenyan Somalis and refugees from Somalia. It is a trade hub for East Africa, a social and economic hub for the global Somali diaspora, and a place regarded as suspect in a country where Somalis have long been marginalized. This article examines Eastleigh as photographic subject and setting, comparing the ubiquity of mobile phone photography there with seldom-practised more traditional forms of photography that are often treated with suspicion in an estate subject to securitized government policy and negative press. It shows how mobile phone photography helps people in the estate communicate visually with the wider Somali diaspora through social media, and how it helps people sell their goods, using as a case study a particular archive of images sent through WhatsApp to the author by Mohaa, a friend of his and a trader in the estate. The article also adds a political dimension to recent anthropological theorizing on mobile photography, showing how, in Eastleigh, Somalis have used photography and social media to take control of the way in which the estate is represented visually, and to demand from the state better services and better treatment.
The anxiety of blowing: experiences of breath and brass instruments in Benin
Authors: Copeland Lyndsey
Published: May 2019

Within amateur musical circles in Benin, one is told that if a male blows too hard into a brass instrument his testicles might swell up, fall off, or even run away. Concerned parents warn their children against ‘blowing’ brass instruments, telling stories of inguinal hernias and infertility, and many maintain that male brass players must take preventative measures. Accompanying this unease about blowing out is a complementary concern with breathing in, and the possible inhalation of micro-organisms or poison through the mouth. Engaging with this anxiety of blowing, this article takes seriously my interlocutors’ concern with the consequences of playing brass instruments on their bodies. My main argument is that understandings of the precarious nature of breath are at the core of musicians’ experiences of anxiety. My exploration of the relation between breath, anxiety and the body supports a common phenomenology of breathing across cultures, and serves to advance breath as an important site of meaning making.
A Climate of Change? The Oil Industry and Decarbonization in Historical Perspective
Authors: Boon Marten
Published: May 2019

Decarbonization has been identified as necessary to preventing catastrophic climate change, creating a dilemma for the global oil industry. This article examines the industry's reaction to this dilemma and focuses on its historical response to market and governmental regulatory pressure. The article argues that differing national climate policies provoked some oil companies to develop proactive decarbonization strategies. However, the continued growth of fossil fuel demand, the industry's vested interests, and the voluntary nature of climate governance have resulted in the industry taking very little meaningful action to achieve decarbonization.
Coding Episode Boundaries with Marked Structures: A Cross-Linguistic Study
Authors: Pu Ming-Ming , Prideaux Gary D.
Published: May 2019

The notion of markedness has played an important role in linguistic theorizing for decades. Originating in Prague School phonological theory, it has also found an important place in morphology, syntax, and semantics (Andersen 1989). In general terms, markedness theory claims that when alternative forms are available, such as alternative construction types or paraphrases, one member of the set,the unmarked member, is more prototypical, is more frequent, has a wider distribution, etc. Within the psycholinguistic literature, it has been argued that the unmarked member of a set will typically be both cognitively and structurally less complex, and hence easier to process than its marked counterpart, a factor which also suggests that, all things being equal, the unmarked member should be acquired earlier than the marked member (e.g., Slobin 1973).
Planned vs Unplanned Discourse: Oral Narrative vs Conversation in Woods Cree
Authors: Starks Donna
Published: May 2019

Most research on Algonquian languages, of which Cree is a typical example, is based on collections of narrative texts (Wolfart 1973; Dahlstrom 1986; James 1986). Although there is nothing intrinsically wrong with this approach, the use of one particular type of database in such an extensive amount of research lends itself to a genre-biased description of the language. In oral cultures, many narrative texts are typically preplanned (Chafe 1985) and therefore will have, according to researchers in discourse analysis, many of the features of preplanned texts such as complete and longer sentences, higher clause density and a larger proportion of subordinate clauses (Brown and Yule 1985:151–117; Biber 1988:47). In addition, other language-specific features may occur.
Joint influence of surface erosion and high-latitude ice-sheet extent on Asian dust cycle during the last glacial maximum
Authors: Li Xinzhou , Liu Xiaodong , Zhou Haibo
Published: May 2019

The dust cycle plays an important role in the long-term evolution of the climate and environment. In this paper, an improved climate model including aerosol processes was used to carry out a set of sensitivity experiments and comparative analyses of the effects of high-latitude ice-sheet extent and abnormal dust erosion, as well as Earth’s orbital parameters and atmospheric greenhouse gas content, on dust activities during the last glacial maximum. The comparative analysis found that incorporating the abnormal surface erosion factor alone could increase dust emissions by 2.77-fold and 3.77-fold of the present-day global and Asian dust emissions, respectively. The high-latitude ice-sheet factor caused global dust emissions to increase by 1.25-fold that of the present day. Sensitivity experiments showed that increased surface erosion in Asia during the last glacial maximum made the greatest contribution to the increased dust emissions in Asia, followed by the high-latitude ice-sheet factor, while the contributions of the greenhouse gas content and orbital parameters were relatively weak. Strong dust emissions during the glacial period were therefore not only dependent on the development of the high-latitude ice sheets but were strongly associated with the underlying surface characteristics of local dust source regions.
The African Charter on Democracy, Elections and Governance: Past, Present and Future
Authors: Wiebusch Micha , Aniekwe Chika Charles , Oette Lutz , Vandeginste Stef
Published: May 2019

This article traces a genealogy of the African Charter on Democracy, Elections and Governance (ACDEG) and examines the charter's overall implementation. While there has always been a struggle between competing views of how to ensure more or less continental accountability for norms related to democratic governance in Africa, enforcement by the African Union (AU) has definitively become more robust since the ACDEG's adoption. The article argues that this development is observable in three trends: continental legalization, technocratization and judicialization of politics. It evaluates the growth of normative commitments in the field of democracy, elections and governance and their increasing consolidation into binding legal treaties; explores the increasing reliance on AU technical assistance in the implementation and interpretation of these instruments; and assesses the expanding role of continental and regional judicial bodies in enforcing commitments to democracy. Building upon a better understanding of these trends, the article identifies key contextual factors that will shape the ACDEG's future implementation.
The Strange Case of Byron Preiss Visual Publications
Authors: WILLIAMS PAUL
Published: May 2019

Between 1976 and 1979 Byron Preiss operated as a book packager specializing in graphic novels, bringing comics creators together on original stories and licensed properties and delivering the finished product to publishing houses. Far from being praised for his efforts, Preiss was attacked by fans and comics professionals for betraying the very medium he professed to uplift. This article explains the industrial shifts behind the rise of Byron Preiss Visual Publications and book-format comics, as well as accounting for the hostility directed against Preiss, a level of vitriol that increased after his collaborators onEmpire(1978) expressed their dismay at the changes he made to the graphic novel before publication.
Casting a Black Gandhi: Martin Luther King Jr., American Pacifists and the Global Dynamics of Race
Authors: HODDER JAKE
Published: May 2019

Martin Luther King Jr. is widely read through his association with Gandhi's ideas and practice. Whilst it is important to neither overstate nor ignore this influence, the paper retraces the work undertaken behind the scenes to script this relationship for wider audiences. It questions how King's casting as America's black Gandhi was strategically undertaken, by whom and for what purposes, as well as exploring why it was ultimately short-lived. Although King experimented with Gandhism briefly in the late 1950s, by the early 1960s the idea had largely been dropped. In particular, the paper focusses on the role played by the American pacifist movement up to, and including, organizing King's visit to India in 1959. These sources are used to make a broader argument that King's ability to inhabit Gandhi's legacy during the movement's early years was critical to forging global anticolonial connections. As such the paper argues that nonviolence was more than a repertoire of resistance techniques, but a spatial mechanism which could fold scale, bridge distance, and thereby produce and reshape racial solidarity itself.
New data on the nervous system ofCercaria parvicaudataStunkard & Shaw, 1931 (Trematoda: Renicolidae): revisiting old hypotheses
Authors: Denisova S.A. , Shchenkov S.V.
Published: May 2019

Data on the interposition of the immunoreactive nerve cords inCercaria parvicaudataStunkard & Shaw, 1931 (Trematoda: Renicolidae) and its chaetotaxy were obtained. The nervous system ofC. parvicaudatawas described using immunostaining of 5-hydroxytryptamine and FMRFamide immunoreactive nerve elements. The morphology and distribution of sensory receptors were analysed using scanning electron microscopy and the silver nitrate impregnation technique. Our integrated approach to the study of the nervous system revealed a clear colocalization of surface papillae with nerve cords and commissures inC. parvicaudata.The structure of the nervous system inC. parvicaudatadiffers partly from the classical model that defines the entire nomenclature of chaetotaxy.
Colonies as dynamic systems: reconstructing the life history of Cribrilina annulata (Bryozoa) on two algal substrates
Authors: Nekliudova Uliana A. , Shunkina Ksenia V. , Grishankov Alexey V. , Varfolomeeva Marina A. , Granovitch Andrey I. , Ostrovsky Andrew N.
Published: May 2019

Quantifying interconnected performances of the modules in a colonial organism (feeding, sexual reproduction, rejuvenation, dormancy) into an integral picture enables studying functional dynamics and resource allocation at different levels – from module to population. Testing this approach on the common boreal-Arctic bryozoanCribrilina annulatain the White Sea, we describe its life history, comparing colonies on two algal substrates with contrasting size and lifespan. Colonies living on kelps were much larger and had a higher proportion of dormant zooids, whereas the percentage of reproducing, feeding and rejuvenating zooids was higher in colonies on red algae (with the colonies also exhibiting longer reproductive period). Colony lifespan was dependent both on substrate type and on time of colony establishment, lasting from 4–5 to up to 17 months on kelps and 14–18 months on red algae. During the reproductive season (May–September) theC. annulatapopulation consisted of colonies of three cohorts on both substrata: overwintered and two summer generations that behaved differently. Whereas overwintered and summer colonies established in June–early August produced larvae, most of the colonies established after mid-summer were preparing for hibernation and postponed reproduction until next spring. Moreover, young reproducing colonies formed brooding hermaphrodite zooids of ordinary size, whereas overwintered colonies budded smaller-sized basal and frontal (dwarf) hermaphrodites. Finally, overall zooidal performance in co-existing colonies of the overwintered and young generations was different on kelps, but similar on red algae. Altogether our findings indicate that the life histories of colonial epibionts are much more complex and evolutionarily flexible than generally acknowledged.
Effect of Imazamethabenz on Histology and Histochemistry of Polysaccharides in the Main Shoot of Wild Oat (Avena fatua)
Authors: Chao Jian Fu , Quick William A. , Hsiao Andrew I. , Xie Hai Sheng
Published: May 2019

Imazamethabenz, an acetohydroxyacid synthase (AHAS)-inhibiting herbicide, was applied at a sublethal rate (200 g ai ha–1) to foliage of greenhouse-grown wild oat plants at the 2-leaf stage without tillers. Main shoot tissues were sampled 1 to 2 wk after imazamethabenz treatment and prepared for light microscopic examination. Histological observations showed that imazamethabenz treatment did not produce drastic changes on leaf structures but did affect chloroplast integrity of fully expanded 2nd leaf and inhibited differentiation of the young 3rd leaf 1 wk after application. The internode length and the number of cells in internodes of the herbicide-treated main stem were greatly reduced, presumably due to the inhibition by imazamethabenz of intercalary meristem cell division in early stages of internode elongation. One week after imazamethabenz application, histochemical studies revealed an increased accumulation of starch granules in chloroplasts of the 2nd leaf but reduced starch levels in the main stem. This confirmed the hypothesis that AHAS inhibitors affected phloem transport of photosynthates.
Dynamics of Subeconomic Threshold Populations of Sicklepod (Cassia obtusifolia) in a Peanut-Cotton-Corn Rotation
Authors: Johnson W. Carroll , Cardina John , Mullinix Benjamin G.
Published: May 2019

Studies were conducted from 1987 to 1990 to measure the dynamics of sicklepod established at subeconomic threshold populations in a peanut-cotton-corn cropping system. The experimental site had no native populations of sicklepod prior to initiation of the study. Main plots were crops in the rotation sequence plus continuous summer fallow (no crop). Subplots were: sicklepod established in the initial year of the study, sicklepod established every year of the study, and no sicklepod. Sicklepod was established at subeconomic threshold densities to simulate weed survival and seed production in fields where economic thresholds were the basis for weed management decisions. Sicklepod growing alone in fallow plots produced more seed per plant, resulting in significantly more seedlings throughout the study than sicklepod growing with crops. Sicklepod growing in corn produced the fewest seed per plant. Seed produced from subeconomic threshold densities established only in the first year caused 7-, 21-, and 20-fold increases in sicklepod populations during the next three seasons compared to the nontreated control.
Effects of Tillage and Rainfall on Atrazine Residue Levels in Soil
Authors: Isensee Allan R. , Sadeghi Ali M.
Published: May 2019

A field study was conducted in 1987 to 1991 to determine the effect of tillage and rainfall on distribution of atrazine in soil. Soil samples (10-cm increments to 50 cm) and crop residue samples were taken at regular intervals after application each year and analyzed for atrazine. Crop residue and living vegetation on no-till plots intercepted 60 to 70% of the applied atrazine; 3 to 16% of the atrazine remained in crop residue 1 to 2 wk later. The amount of atrazine recovered in soil, 1 to 2 wk posttreatment, ranged from 22 to 59 and 47 to 73% of the amount applied for no-till and conventional till, respectively. An average of 2.6 times more atrazine was recovered in the surface 10 cm of soil under conventional till than under no-till for all samplings and years. Total amounts of atrazine in the sampled profile (0- to 50-cm depth) were also generally lower under no-till than conventional till. More leaching below 10 cm occurred under no-till than conventional till, particularly in 1988 and 1990 when rain fell soon after application. Variation in soil atrazine levels among years was related to timing and amount of the first and subsequent rainfall after application.
A Rapid Microtitre Plate Assay for Determining Sensitivity to Photosystem II Herbicides
Authors: Anderson Michael P. , Bensch Curtis N. , Stritzke Jimmy F.
Published: May 2019

This paper reports on a microtitre plate version of the 2,6-dichlorophenol-indophenol (DCPIP) reduction assay. DCPIP reduction rates of alfalfa thylakoid membranes were determined by measuring absorbance at 600 nm before and after a 1 min illumination period. The membranes were near light-saturated at intensities above 600 μE m–2s–1. Saturation of thylakoid membranes with DCPIP occurred above 120 μM. DCPIP reduction rates increased linearly with chlorophyll concentrations from 0.25 to 2 μg. The rate of DCPIP reduction was linear throughout a 2 min illumination period (R2= 0.99). The assay was sensitive enough to terbacil to differentiate between a 20% change in the I50concentration. DCPIP reduction rates were sensitive to concentrations of terbacil as low as 100 nM. It only takes 13 minutes to load and read 96 samples using the microtitre plate assay compared to 5.5 h using the conventional procedure.
Kochia (Kochia scoparia) Pollen Dispersion, Viability and Germination
Authors: Mulugeta Dawit , Maxwell Bruce D. , Fay Peter K. , Dyer William E.
Published: May 2019

Kochia pollen dispersion was measured during 24 and 48 h periods from a kochia population in an 8- by 10-m area in the center of a 1.6 ha fallow field. Pollen counts from traps at 50- and 100-cm heights declined rapidly with increasing distance from the pollen source. Pollen deposition was highest along the prevailing wind direction: up to 23 pollen grains cm–2were recovered 50 m from the pollen source along the southeast (SE) vector. Nonlinear regression analysis of pollen deposition along the SE vector was used to estimate that 99.9% of shed pollen would be deposited within 154.4 m of the source. Viability of pollen from greenhouse- and field-grown plants was measured using staining and germination assays. of four pollen stains tested, only 1,2,3-triphenyl tetrazolium chloride gave consistent results and did not stain heat-killed pollen. Depending on environmental conditions, kochia pollen remained viable from less than 1 d to 12 d. Length of kochia pollen viability was shortest under high temperatures (22 and 28 C) and low relative humidity (7 and 32%). Less than 0.5% germination was observed in 1.1% agar media with various additions; however, up to 17.8% germination was observed after incubation at 28 C in 100% relative humidity.
Interference of Redroot Pigweed (Amaranthus retroflexus) in Corn (Zea mays)
Authors: Knezevic Stevan Z. , Weise Stephan F. , Swanton Clarence J.
Published: May 2019

Redroot pigweed is a major weed in corn throughout Ontario. Field experiments were conducted at two locations in 1991 and 1992 to determine the influence of selected densities and emergence times of redroot pigweed on corn growth and grain yield. Redroot pigweed densities of 0.5, 1, 2, 4 and 8 plants per m of row were established within 12.5 cm on either side of the corn row. In both years, redroot pigweed seeds were planted concurrently and with corn at the 3- to 5-leaf stage of corn growth. A density of 0.5 redroot pigweed per m of row from the first (earlier) emergence date of pigweed (in most cases, up to the 4-leaf stage of corn) or four redroot pigweed per m of row from the second (later) emergence date of pigweed (in most cases, between the 4- and 7-leaf stage of corn) reduced corn yield by 5%. Redroot pigweed emerging after the 7-leaf stage of corn growth did not reduce yield. Redroot pigweed seed production was dependent upon its density and time of emergence. The time of redroot pigweed emergence, relative to corn, may be more important than its density in assessing the need for postemergence control.
Uptake, Translocation, and Metabolism of Picloram and Metsulfuron Methyl by Two Locoweed Species
Authors: Sterling Tracy M. , Jochem Heidi S.
Published: May 2019

The locoweeds, woolly loco and silky crazyweed, contribute to livestock poisoning in the western United States. Differences in response of these two locoweeds to foliar-applied picloram and metsulfuron was investigated by evaluating differences in herbicide uptake, translocation, and metabolism. Silky crazyweed compared to woolly loco was more than 10 times as sensitive to increasing rates of either herbicide. The two species absorbed 8 to 15%, and 11 to 17% of applied picloram and metsulfuron, respectively. Translocation of picloram and metsulfuron out of treated leaflets of either species was less than 3% of that absorbed after 96 h. Approximately 70 and 100% of the absorbed herbicides remained as picloram and metsulfuron, respectively, in both species. Therefore, differences in picloram or metsulfuron uptake, translocation, and metabolism appear inadequate to account for the differential response to each herbicide by the two locoweed species. Selectivity differences between these locoweed genera to picloram and metsulfuron most likely are due to sensitivity differences at sites of action.
Disappearance of DIBOA-glucoside, DIBOA, and BOA from Rye (Secale cerealeL.) Cover Crop Residue
Authors: Yenish Joseph P. , Worsham A. Douglas , Chilton W. Scott
Published: May 2019

Disappearance of rye cover crop residue and allelochemicals from rye residue were evaluated in a field study at Clayton, NC, in 1992 and 1993. The aerial portion of rye biomass declined linearly over time with 50% of the residue disappearing by 105 d after clipping. Extrapolations indicated all residue would disappear approximately 200 d after rye clipping. Total content of DIBOA and two related compounds, DIBOA-glucoside and BOA, in the residue also was measured over time. Fifty percent of the 0-d content of the compounds disappeared from residue 10 and 12 d after kill for 1992 and 1993, respectively. Extrapolations indicated content reached 0121 and 168 d after kill for 1992 and 1993, respectively. Reported duration of weed suppression by rye cover crops more closely follows disappearance of allelochemicals from rye residue than disappearance of the residue.
Physiological Mechanism for Tall Morningglory (Ipomoea Purpurea) Resistance to DPX-PE350
Authors: Sunderland Shay L. , Burton James D. , Coble Harold D. , Maness Eleanor P.
Published: May 2019

Laboratory experiments were conducted to determine the physiological mechanism of tall morningglory resistance to the experimental cotton herbicide DPX-PE350. Tall morningglory, a resistant species, was compared with entireleaf morningglory, a sensitive species, to evaluate inhibition at the site of action, the acetolactate synthase (ALS) enzyme (E.C.4.1.3.18), by DPX-PE350 as well as uptake, translocation, and metabolism of DPX-PE350. No differences were found between species in the concentration required to inhibit the ALS enzyme by 50% (I50), or in uptake and translocation of the herbicide. Tall morningglory metabolized the herbicide more rapidly than did entireleaf morningglory. Tall morningglory contained 3.6 and 1.4 times more metabolites of DPX-PE350 than did entireleaf morningglory 6 and 24 h after treatment, respectively. Tall morningglory produced anO-desmethyl metabolite from the 3,5-dimethoxypyrimidine moiety of DPX PE350 that was not found in entireleaf morningglory. These data suggest that the ability of tall morningglory to more rapidly metabolize DPX-PE350, possibly through the production of the pyrimidinyldesmethyl metabolite, may be the mechanism of resistance to DPX-PE350.
Molecular Characterization of the Tubulin-Related Gene Families in Herbicide Resistant and Susceptible Goosegrass (Eleusine indica)
Authors: Mysore Kirankumar S. , Baird Wm. Vance
Published: May 2019

Goosegrass, wide spread throughout the tropics and subtropics, is one of the most noxious weeds known. Recently, biotypes of goosegrass have been found resistant to the dinitroaniline herbicides. An alteration in the structure/composition of a tubulin protein has been postulated as an explanation for the hyperstable microtubules and the resistant phenotype. Our study was initiated to investigate the structure of the alpha (α)-, beta (β)- and gamma (γ)-tubulin related gene sequences in resistant, intermediately resistant, and susceptible biotypes. Heterologous tubulin gene clones were used as probes of restriction endonuclease-digested genomic DNA from each biotype, to determine gene size and copy number and to screen for restriction fragment length polymorphisms. The tubulin genes are organized into gene families. There are three to five α-tubulin genes, four to seven β-tubulin genes, and four to eight γ-tubulin genes. There was no evidence of multiple copies or tandem repeats of any individual gene sequence. Although RFLPs were observed, no significant difference in the banding pattern between the resistant and the susceptible biotypes was found for either α-, β-, or γ-tubulin gene families. Therefore, it is unlikely that the difference between the herbicide-response phenotypes can be attributed to large deletions or insertions in a tubulin gene.
Herbicidal Activity of UCC-C4243 and Acifluorfen is Due to Inhibition of Protoporphyrinogen Oxidase
Authors: Wright Terry R. , Fuerst E. Patrick , Ogg Alex G. , Nandihalli Ujjana B. , Lee Hee Jae
Published: May 2019

Laboratory and greenhouse studies were conducted to determine the mode of action of soil- and foliar-applied UCC-C4243. Experiments demonstrated that UCC-C4243 required light for phytotoxicity, phytotoxic symptoms were similar to inhibitors of porphyrin synthesis such as acifluorfen, and UCC-C4243 potently inhibited protoporphyrinogen oxidase. Germination and emergence of field pennycress and lentil in the dark were not affected by soil-incorporated UCC-C4243 at rates more than 10 times greater than like treatments that killed all plants in the light. Soil-incorporated UCC-C4243 required light for activity and killed seedlings within 1 d after emergence; sublethal doses caused desiccation, veinal necrosis, and leaf deformation. Field pennycress and lentil were susceptible to soil-incorporated UCC-C4243 and acifluorfen in the light, but were 5 to 93 times less sensitive to the herbicides in the dark. Wheat was not affected by either herbicide in the light or dark. Injury symptoms from UCC-C4243 applied POST to redroot pigweed were similar to symptoms from diphenyl ether and bipyridinium herbicides: rapid, light-dependent chlorophyll bleaching, desiccation, and necrosis. UCC-C4243, acifluorfen-methyl, and acifluorfen acid caused light- and concentration-dependent chlorophyll bleaching and electrolyte leakage from cucumber leaf disks (I50= 1.0, 1.8, and 4.3 μM, respectively). An inhibitor of the porphyrin synthesis pathway, 4,6-dioxoheptanoic acid, almost completely inhibited herbicide-induced electrolyte leakage. δ-Aminolevulinic acid, a tetrapyrrole precursor and stimulator of the porphyrin synthesis pathway, caused synergistic effects with each herbicide. Protoporphyrinogen oxidase from barley etioplast preparations was inhibited 50% by 40 nM UCC-C4243. Barley leaf sections treated with 100 μM UCC-C4243 accumulated protoporphyrin IXin vivoto levels > 75 times non-treated controls. These data indicate the light-requiring herbicide activity of UCC-C4243, like acifluorfen, is due to inhibition of protoporphyrinogen oxidase.
Crop Planting Pattern Effects on Early Growth and Canopy Shape of Cultivated and Wild Oats (Avena fatua)
Authors: Regnier Emilie E. , Bakelana Kufimfutu B.
Published: May 2019

Field studies were conducted to determine the effects of cultivated oats planting pattern on early canopy shape and growth of cultivated oats and wild oats, in part to test the assumption of radial plant canopy expansion on which previous theoretical models of crop-weed interference models have been based. Cultivated oats density was kept constant as the pattern rectangularity was varied, and single wild oats plants were centered within each pattern. Individual plant canopies, photographed from above 31 days after emergence (DAE), were radial for wild oats in all crop planting patterns and for cultivated oats planted in triangular and square planting patterns. Canopy radius perpendicular to the crop row axis in rectangular patterns was similar to canopy radius along the same cardinal axis in equidistant patterns, but was reduced along the crop row axis, resulting in a rectangular canopy shape and decreased canopy area in rectangular compared to equidistant patterns. Cultivated oats dry weight and leaf area at crop flowering (64 DAE) also decreased with increasing rectangularity of crop planting pattern. Reductions in cultivated oats growth in rectangular patterns were associated with earlier intraspecific interference and delayed crop canopy closure in rectangular compared to equidistant patterns. Wild oats leaf area and tiller number 64 DAE decreased with more equidistant crop planting patterns, consistent with reduced canopy area 31 DAE and earlier crop canopy closure in equidistant patterns. The data suggest that individual oats canopy expansion during early growth is essentially radial and also support previous theoretical predictions of crop planting pattern effects on weed suppression.
Efficacy of Imazethapyr in Peanut (Arachis hypogaea) as Affected by Time of Application
Authors: York Alan C. , Wilcut John W. , Swann Charles W. , Jordan David L. , Walls F. Robert
Published: May 2019

Experiments conducted in North Carolina and Virginia compared weed control, peanut yield, and net returns with systems using imazethapyr applied at various times and the regional standard treatment of paraquat applied at the ground-cracking stage of peanut (GC) followed by acifluorfen plus bentazon applied POST. Imazethapyr was applied PPI, PRE, GC, or POST at 70 g ae ha−1. Imazethapyr also was applied sequentially PPI plus GC, PPI plus POST, and PRE plus POST at 35 + 35 and 70 + 70 g ha−1. Late-season control of common ragweed and a mixture of entireleaf, ivyleaf, and pitted morningglories by the standard treatment ranged from 85 to 100%. Spurred anoda was controlled 80%, and common lambsquarters and prickly sida were controlled completely. Control of common lambsquarters, prickly sida, and morningglory by imazethapyr applied one or more times was similar to control by the standard. Control by imazethapyr exceeded that by the standard only for spurred anoda. The most effective time for applying imazethapyr varied by species and locations. Imazethapyr was equally effective on common lambsquarters and spurred anoda when applied PPI, PRE, or GC. Prickly sida and morningglory were controlled best when imazethapyr was applied PPI or PRE and GC, respectively. Common ragweed was controlled poorly with single applications of imazethapyr. Applying imazethapyr sequentially improved consistency of control across the range of species. In most cases, imazethapyr applied sequentially at 35 + 35 g ha−1controlled all weeds as well as or better than when applied once at 70 g ha−1. Overall, imazethapyr at the registered rate of 70 g ha−1was most effective when applied PPI at 35 g ha−1followed by 35 g ha−1at GC. Except for common ragweed, weed control with this treatment was similar to that by the standard. Peanut yield and net returns with this treatment were similar to those with the standard at three of four locations.
Influence of Small Grain Crops on Weeds and Ecofallow Corn (Zea mays)
Authors: Wicks Gail A. , Mahnken Garold W. , Hanson Gordon E.
Published: May 2019

Spring small grains were not as competitive with barnyardgrass and witchgrass as winter wheat. Winter wheat grain yields were greater than spring barley or spring wheat in 1986, 1987, and 1988 and oat in 1986 and 1988. Barnyardgrass, stinkgrass, and witchgrass control with glyphosate plus 2,4-D plus atrazine at 0.6 plus 0.8 plus 1.7 kg ha−1was usually less when the herbicides were applied to stubble of spring small grain versus winter wheat due to the advanced weed growth at treatment Barnyardgrass and witchgrass were more difficult to control than stinkgrass, redroot pigweed, tumble pigweed, kochia, and tumble thistle. No-till corn planted into winter wheat stubble had fewer barnyardgrass and witchgrass than corn planted into spring wheat stubble. The addition of metolachlor plus atrazine at 1.7 plus 0.6 kg ha−1eliminated differences among small grain cultivars in weed control in corn. Corn grain yields from winter wheat plots were greater than other small grains in 1989 because of better weed control and more crop residue.
Pause behavior within reformulations and the proficiency level of second language learners of English
Authors: Williams Simon A. , Korko Malgorzata
Published: May 2019

This research reports on a quantitative analysis of the combination of two types of disfluency, reformulations and pauses, in the speech of lower intermediate and advanced speakers of English as a second language (L2). The present study distinguishes between corrections and false starts within the category of reformulations as well as between silent and filled pauses. It focuses on the extent to which pause behavior within reformulations varies according to the stage of L2 development and the type of reformulation used. An analysis was made of 56 L2 speakers’ 2-min monologues. The results showed that lower intermediate and advanced speakers differed on the frequency of silent pauses inserted in corrections but not on their frequency in false starts. This suggests that false starts depend less on proficiency level, and may reflect temporary problems with conceptual encoding or extralinguistic factors that contribute to the efficacy of L2 production rather than difficulties with linguistic processing per se. The frequency of silent pauses rather than silent pause duration or the frequency and duration of filled pauses appeared to be the only marker to differentiate between false starts and corrections across the two proficiency groups.
A cat-and-Maus game: the politics of truth and reconciliation in post-conflict comics
Authors: Redwood Henry , Wedderburn Alister
Published: May 2019

Several scholars have raised concerns that the institutional mechanisms through which transitional justice is commonly promoted in post-conflict societies can alienate affected populations. Practitioners have looked to bridge this gap by developing ‘outreach’ programmes, in some instances commissioning comic books in order to communicate their findings to the people they seek to serve. In this article, we interrogate the ways in which post-conflict comics produce meaning about truth, reconciliation, and the possibilities of peace, focusing in particular on a comic strip published in 2005 as part of the Sierra Leone Truth and Reconciliation Commission Report into the causes and crimes of the 1991–2002 Civil War. Aimed at Sierra Leonean teenagers, the Report tells the story of ‘Sierrarat’, a peaceful nation of rats whose idyllic lifestyle is disrupted by an invasion of cats. Although the Report displays striking formal similarities with Art Spiegelman's Maus (a text also intimately concerned with reconciliation, in its own way), it does so to very different ends. The article brings these two texts into dialogue in order to explore the aesthetic politics of truth and reconciliation, and to ask what role popular visual media like comics can play in their practice and (re)conceptualisation.
Transformation of LQR Weights for Discretization Invariant Performance of PI/PID Dominant Pole Placement Controllers
Authors: Halder Kaushik , Das Saptarshi , Gupta Amitava
Published: May 2019

Linear quadratic regulator (LQR), a popular technique for designing optimal state feedback controller, is used to derive a mapping between continuous and discrete time inverse optimal equivalence of proportional integral derivative (PID) control problem via dominant pole placement. The aim is to derive transformation of the LQR weighting matrix for fixed weighting factor, using the discrete algebraic Riccati equation (DARE) to design a discrete time optimal PID controller producing similar time response to its continuous time counterpart. Continuous time LQR-based PID controller can be transformed to discrete time by establishing a relation between the respective LQR weighting matrices that will produce similar closed loop response, independent of the chosen sampling time. Simulation examples of first/second order and first-order integrating processes exhibiting stable/unstable and marginally stable open loop dynamics are provided, using the transformation of LQR weights. Time responses for set-point and disturbance inputs are compared for different sampling times as fraction of the desired closed loop time constant.
Climatic drivers of dipterocarp mass-flowering in South-East Asia
Authors: Chechina Mariya , Hamann Andreas
Published: May 2019

Dipterocarpaceae, a dominant family of trees in South-East Asian tropical forests, are remarkable in that they exhibit supra-annual mass-flowering events. The flowering patterns are related to the El Niño Southern Oscillation, but the mechanism that precipitates mass-flowering is still debated. Here, we test if a cumulative-trigger model that tracks resource availability, specifically light, may better explain dipterocarp phenology than a direct-environmental-trigger mechanism. Using 11 flowering time series with an average length of 29 y and variety of candidate predictor variables (precipitation, cloud cover, minimum temperature and El Niño indices) we could not find a plausible direct-environmental-trigger (median AUCs across regions from 0.53 to 0.57 indicating near random predictions). The cumulative-trigger model based on El Niño indices showed better predictive results (AUC 0.67), which could further be improved by resetting the resource at known flowering events (AUC 0.76). Additional support for a cumulative-trigger model comes from the observation that regional differences in the time of year of peak flowering correspond to where El Niño effects are strongest. We conclude that cumulative resource tracking is an evolutionary plausible trigger mechanism that has other primary evolutionary advantages, such as predator satiation.
Obstacles and opportunities: labour emigration to the ‘British World’ in the nineteenth century
Authors: Harper Marjory
Published: May 2019

Labour emigrants in the nineteenth century had ever-increasing access to a global employment market. Many of those who left Great Britain looked beyond Europe, to the British Empire and the United States. They took advantage of improvements in transportation, and followed a wide variety of occupations. Decisions to emigrate were often shaped by their involvement in trade unions and were based on concerns about living standards and working conditions. This study considers a selection of globetrotting British settlers and sojourners who went to Canada, the United States and Australia between 1815 and the 1880s. The article analyses the historiography of labour migration; carries out an empirical study constructed around four pieces of analytical scaffolding; and closes by identifying recurring threads in the multi-hued tapestry of labour emigration, highlighting how concerns and traditions about recruitment, wages and working conditions, which had emerged in the nineteenth century, created legacies that persisted into the period after the First World War.
Social vulnerability, social structures and household grain shortages in sixteenth-century inland Flanders
Authors: Van Onacker Eline
Published: May 2019

‘Vulnerability’ and ‘resilience’ have recently become hot topics in historiography. The main focus is on systemic vulnerability: the reasons why certain societies were better able to overcome crisis. In this article I want to address another type of vulnerability – inspired by the insights of Wisner and Blaikie: social vulnerability, and the differentiated impact of crisis on different social groups. Based on a unique corpus of sources – the grain censuses drafted during the grain crisis of 1556/57 – and a reconstruction of household budgets, I will reconstruct vulnerable groups, the root causes behind their vulnerability, and their coping mechanisms. By doing this I will show how systemic resilience could go hand-in-hand with vulnerable people, thus adding more depth to a growing research strand.
Predicting Progression to Parkinson’s Disease Dementia Using Multivariate Normative Comparisons
Authors: Agelink van Rentergem J.A. , de Vent N.R. , Huizenga H.M. , Murre J.M.J. ,   ANDI consortium, Schmand B.A.
Published: May 2019

Objective:Parkinson’s disease with mild cognitive impairment (PD-MCI) is a risk factor for progression to PD dementia (PDD) at a later stage of the disease. The consensus criteria of PD-MCI use a traditional test-by-test normative comparison. The aim of this study was to investigate whether a new multivariate statistical method provides a more sensitive tool for predicting dementia status at 3- and 5-year follow-ups. This method allows a formal evaluation of a patient’s profile of test scores given a large aggregated database with regression-based norms.Method:The cognitive test results of 123 newly diagnosed PD patients from a previously published longitudinal study were analyzed with three different methods. First, the PD-MCI criteria were applied in the traditional way. Second, the PD-MCI criteria were applied using the large aggregated normative database. Last, multivariate normative comparisons (MNCs) were made using the same aggregated normative database. The outcome variable was progression to dementia within 3 and 5 years.Results:The MNC was characterized by higher sensitivity and higher specificity in predicting progression to PDD at follow-up than the two PD-MCI criteria methods, although the difference in classification accuracy did not reach statistical significance.Conclusion:We conclude that MNCs could allow for a more accurate prediction of PDD than the traditional PD-MCI criteria, because there are encouraging trends in both increased sensitivity and increased specificity. (JINS, 2019,25, 678–687)
Standardization of an Arabic-Language Neuropsychological Battery for Epilepsy Surgical Evaluations
Authors: Al-Joudi Haya F. , Mincari Lina , Baz Salah , Nester Michael , Al-Marzouki Najla , Abalkhail Tariq , Aljehani Noha , Al-Ibrahim Camellia , Brandt Jason
Published: May 2019

Objectives: This study provides a standardized Arabic language neuropsychological test battery and tests its ability to distinguish patients with left and right hemisphere epileptic foci who are candidates for surgical resection. Methods: An Arabic language battery of 15 tests was developed based on the neuropsychological test battery used at the Johns Hopkins Hospital for surgical evaluation of patients undergoing temporal lobe resection. With modifications where culturally required, 11 tests were translated to Arabic by the principal investigator and back-translated by two bilingual health professionals; four tests were available in Arabic and added to the battery. The battery was administered to 21 Arabic-speaking patients with left temporal epileptic foci, 21 with right temporal epileptic foci, and 46 neurologically and psychiatrically healthy adults. Results: Nearly all the Arabic test versions were capable of differentiating healthy controls and the temporal lobe epilepsy (TLE) groups. Tests known to distinguish left and right temporal lobectomy candidates, such as wordlist memory and prose recall, were able to do so as accurately as the English versions. Also, a roughly “culturally free” task (the Baltimore Board) and a newly developed version of the Boston Naming Test demonstrated some sensitivity to left temporal lobe involvement. Conclusions: Arabic-language neuropsychological tests for epilepsy surgical evaluations are made available, demonstrate cultural sensitivity and clinical validity, and require further psychometric property and normative research. (JINS, 2019, 25, 761–771)