Preliminary analysis of whether mosquitoes can carry and transmit African swine fever

Background Mosquitoes are important insect vectors, but whether they can carry and transmit African swine fever virus (ASFV) in large-scale pig farms in China is unknown. Results In this study, probe-based qPCR analysis was performed on mosquitoes from five pig farms with ASF virus (ASFV). Analysis of ASFV in 463 mosquitoes yielded negative cycle threshold (CT) value), and detection remained negative after mixing samples from all five pig farms. Conclusions Therefore, mosquitoes appear unlikely to transmit ASFV, and pose little threat to large-scale pig farms. Thus, farms should continue to follow normal mosquito control procedures when formulating strategies for the prevention and control of ASF.

Preliminary Analysis of African Swine Fever Virus Carriage and Transmission by Mosquitoes

BackgroundMosquitoes are important insect vectors, but whether they can carry and transmit African swine fever virus (ASFV) in large-scale pig farms in China is unknown. ResultsIn this study, probe qPCR analysis was performed on mosquitoes from five pig farms with ASF virus (ASFV). Analysis of ASFV in 463 mosquitoes yielded negative cycle threshold (CT) value), and detection remained negative after mixing samples from all five pig farms. ConclusionsTherefore, mosquitoes appear unlikely to transmit ASFV, and pose little threat to large-scale pig farms. Thus, farms should continue to follow normal mosquito control procedures when formulating strategies for the prevention and control of ASF.

The Arabic Negative Cycle: An Example of Historical Changes in the Arabic Language

This study considers negation in 47 modern Arabic varieties. The types of negation investigated are standard negation and non-verbal negation. The study reveals that negation in Arabic is undergoing a cycle in addition to the Jespersen’s Cycle, which has already been identified by several studies. In the first stage of this additional cycle, a single negator is used to negate both verbal and non-verbal clauses. In the second stage, this negator is attached to a personal pronoun to negate non-verbal clauses only. In the third stage, a new single morpheme is coined and generalised to negate any non-verbal clause. In the fourth stage, this new morpheme is used to negate certain types of verbal clauses. In the last stage, verbal and non-verbal clauses return to be negated similarly, and this newly coined morpheme can negate both of them. In the study, this cycle is referred to as the Arabic negative cycle.

Parallels between the negative cycle and the rise of interrogative marking in French

In this paper, I discuss a type of construction that is rarely if ever mentioned in connection with diachronic cyclicity: wh-interrogative marking. In particular, I shall compare sentential negation with wh-marking in French and point to interesting commonalities between the prototypical diachronic cycle (negation) and interrogative marking. The pragmatic contrast between question types in Old French is shown to be mirrored in a similar contrast in Modern French, with the previously “strong” est-ce que interrogative now being a weaker one. In addition, I argue that reversal of anaphoric direction is another shared feature in the history of negation and of the est-ce que interrogative.

Introduction

In Section 1 of my introduction to this Special Issue, I define the concept of semantic–pragmatic cycles, a relatively recently discovered phenomenon, drawing a distinction between two sub-types: onomasiological and semasiological cycles. Semantic–pragmatic cycles are contrasted with the more widely known (morpho-)syntactic cycles such as the Negative Cycle (or Jespersen Cycle), and I discuss possible connections between these two types of cycles. Finally, I raise some questions for further research. In Section 2, I outline the empirical and/or theoretical contribution of each of the six papers that follow – considering, in particular, how they contribute to elucidating the role of pragmatics in cyclic change.

Consumer preferences and purchasing rationales for wine: a multivariate data analysis

The wine market is very heterogeneous and complex, being the knowledge of the behaviour and attitudes of consumers a key tool to design efficient marketing plans, namely in countries that are traditionally wine producers and consumers, such as Portugal. In this country, Port wine is an economic and cultural icon, but, in the last decade, total sales have been decreasing. Despite this trend the domestic consumption has been gaining relevance and therefore a focus to reverse the negative cycle of total sales. The main goal of this paper is to analyse the profile and behaviour of domestic Port wine consumers, identifying homogeneous market segments. For this purpose, an online survey was applied and random sample of 678 Portuguese Port wine consumers was collected. Using multivariate statistical techniques, three profiles of purchasers/consumers emerged: experienced, less experienced and inexperienced consumers. This segmentation shows that Port wine consumers can be grouped according to their involvement with the product, consumption occasion and price they are willing to pay. In addition to the academic contribution of wine market segmentation, the paper provides useful insights to be used in designing marketing plans, both by institutional stakeholders and wineries.

Homomorphisms of Sparse Signed Graphs

The notion of homomorphism of signed graphs, introduced quite recently, provides better interplay with the notion of minor and is thus of high importance in graph coloring. A newer, but equivalent, definition of homomorphisms of signed graphs, proposed jointly by the second and third authors of this paper and Thomas Zaslavsky, leads to a basic no-homomorphism lemma. According to this definition, a signed graph $(G, \sigma)$ admits a homomorphism to a signed graph $(H, \pi)$ if there is a mapping $\phi$ from the vertices and edges of $G$ to the vertices and edges of $H$ (respectively) which preserves adjacencies, incidences, and signs of closed walks (i.e., the product of the sign of their edges). For $ij=00, 01, 10, 11$, let $g_{ij}(G,\sigma)$ be the length of a shortest nontrivial closed walk of $(G, \sigma)$ which is, positive and of even length for $ij=00$, positive and of odd length for $ij=01$, negative and of even length for $ij=10$, negative and of odd length for $ij=11$. For each $ij$, if there is no nontrivial closed walk of the corresponding type, we let $g_{ij}(G, \sigma)=\infty$. If $G$ is bipartite, then $g_{01}(G,\sigma)=g_{11}(G,\sigma)=\infty$. In this case, $g_{10}(G,\sigma)$ is certainly realized by a cycle of $G$, and it will be referred to as the \emph{unbalanced-girth} of $(G,\sigma)$. It then follows that if $(G,\sigma)$ admits a homomorphism to $(H, \pi)$, then $g_{ij}(G, \sigma)\geq g_{ij}(H, \pi)$ for $ij \in \{00, 01,10,11\}$. Studying the restriction of homomorphisms of signed graphs on sparse families, in this paper we first prove that for any given signed graph $(H, \pi)$, there exists a positive value of $\epsilon$ such that, if $G$ is a connected graph of maximum average degree less than $2+\epsilon$, and if $\sigma$ is a signature of $G$ such that $g_{ij}(G, \sigma)\geq g_{ij}(H, \pi)$ for all $ij \in \{00, 01,10,11\}$, then $(G, \sigma)$ admits a homomorphism to $(H, \pi)$. For $(H, \pi)$ being the signed graph on $K_4$ with exactly one negative edge, we show that $\epsilon=\frac{4}{7}$ works and that this is the best possible value of $\epsilon$. For $(H, \pi)$ being the negative cycle of length $2g$, denoted $UC_{2g}$, we show that $\epsilon=\frac{1}{2g-1}$ works. As a bipartite analogue of the Jaeger-Zhang conjecture, Naserasr, Sopena and Rollovà conjectured in [Homomorphisms of signed graphs, {\em J. Graph Theory} 79 (2015)] that every signed bipartite planar graph $(G,\sigma)$ satisfying $g_{ij}(G,\sigma)\geq 4g-2$ admits a homomorphism to $UC_{2g}$. We show that $4g-2$ cannot be strengthened, and, supporting the conjecture, we prove it for planar signed bipartite graphs $(G,\sigma)$ satisfying the weaker condition $g_{ij}(G,\sigma)\geq 8g-2$. In the course of our work, we also provide a duality theorem to decide whether a 2-edge-colored graph admits a homomorphism to a certain class of 2-edge-colored signed graphs or not.

Croft’s cycle in Arabic: The negative existential cycle in a single language

The negative existential cycle has been shown to be operative in several language families. Here it is shown that it also operates within a single language. It happens that the existential fī that has been adduced as an example of a type A in the Arabic of Damascus, Syria, negated with the standard spoken Arabic verbal negator mā, does not participate in a negative cycle, but another Arabic existential particle does. Reflexes of the existential particle šay(y)/šē/šī/ši of southern peninsular Arabic dialects enter into a type A > B configuration as a univerbation between mā and the existential particle ši in reflexes of maši. It also enters that configuration in others as a univerbation between mā, the 3rd-person pronouns hū or hī, and the existential particle šī in reflexes of mahūš/mahīš. At that point, the existential particle šī loses its identity as such to be reanalyzed as a negator, with reflexes of mahūš/mahīš negating all manner of non-verbal predications except existentials. As such, negators formed of reflexes of šī skip a stage B, but they re-enter the cycle at stage B > C, when reflexes of mahūš/mahīš begin negating some verbs. The consecutive C stage is encountered only in northern Egyptian and southern Yemeni dialects. An inchoate stage C > A appears only in dialects of Lower Egypt.