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The eggplant fruit and shoot borer (EFSB) is a devastating pest of eggplants (Solanum aethiopicum L. and Solanum melongena L.) in Ghana, causing significant economic losses. Although initially thought to be the Leucinodes orbonalis Guenee species found in Asia, recent European and Mediterranean Plant Protection Organization reports suggest its absence in Africa. However, eight Leucinodes species have been recently described in Africa, including two new species, Leucinodes africensis sp. n. and Leucinodes laisalis Walker, which were intercepted in eggplant fruits exported from Ghana to the United Kingdom. Despite the reported absence of L. orbonalis in Africa, it remains on the pest list of Ghana as a species known to attack eggplants. To accurately determine the identity of the EFSB complex occurring on eggplant in Southern Ghana, molecular and morphological taxonomic tools were employed, and adult male populations were monitored in on-farm conditions. Our results revealed the presence of two EFSB species, L. africensis and L. laisalis, in the shoot and fruits of eggplants, with L. africensis being the dominant species and widely distributed in Southern Ghana. Notably, L. africensis males were attracted to the pheromone lure of L. orbonalis despite the two species being biologically distinct. This study provides crucial information on correctly identifying the EFSB species attacking eggplants in Southern Ghana and has significant implications for developing management interventions against these pests and their effects on international eggplant trade.
This study investigated the association between early extubation (EE) and the degree of postoperative intensive care unit (ICU) support after the Fontan procedure, specifically evaluating the volume of postoperative intravenous fluid (IVF) and vasoactive-inotropic score (VIS).
Methods:
Retrospective analysis of patients who underwent Fontan palliation from 2008 to 2018 at a single center was completed. Patients were initially divided into pre-institutional initiative towards EE (control) and post-initiative (modern) cohorts. Differences between the cohorts were assessed using t-test, Wilcoxon, or chi-Square. Following stratification by early or late extubation, four groups were compared via ANOVA or Kruskal-Wallis Test.
Results:
There was a significant difference in the rate of EE between the control and modern cohorts (mean 42.6 versus 75.7%, p = 0.01). The modern cohort demonstrated lower median VIS (5 versus 8, p = 0.002), but higher total mean IVF (101±42 versus 82 ±27 cc/kg, p < 0.001) versus control cohort. Late extubated (LE) patients in the modern cohort had the highest VIS and IVF requirements. This group received 67% more IVF (140 ± 53 versus 84 ± 26 cc/kg, p < 0.001) and had a higher median VIS at 24 hours (10 (IQR, 5–10) versus 4 (IQR, 2–7), p < 0.001) versus all other groups. In comparison, all EE patients had a 5-point lower median VIS when compared to LE patients (3 versus 8, p= 0.001).
Conclusions:
EE following the Fontan procedure is associated with reduced post-operative VIS. LE patients in the modern cohort received more IVF, potentially identifying a high-risk subgroup of Fontan patients deserving of further investigation.
Smoking prevalence is higher amongst individuals with schizophrenia and depression compared with the general population. Mendelian randomisation (MR) can examine whether this association is causal using genetic variants identified in genome-wide association studies (GWAS).
Methods
We conducted two-sample MR to explore the bi-directional effects of smoking on schizophrenia and depression. For smoking behaviour, we used (1) smoking initiation GWAS from the GSCAN consortium and (2) we conducted our own GWAS of lifetime smoking behaviour (which captures smoking duration, heaviness and cessation) in a sample of 462690 individuals from the UK Biobank. We validated this instrument using positive control outcomes (e.g. lung cancer). For schizophrenia and depression we used GWAS from the PGC consortium.
Results
There was strong evidence to suggest smoking is a risk factor for both schizophrenia (odds ratio (OR) 2.27, 95% confidence interval (CI) 1.67–3.08, p < 0.001) and depression (OR 1.99, 95% CI 1.71–2.32, p < 0.001). Results were consistent across both lifetime smoking and smoking initiation. We found some evidence that genetic liability to depression increases smoking (β = 0.091, 95% CI 0.027–0.155, p = 0.005) but evidence was mixed for schizophrenia (β = 0.022, 95% CI 0.005–0.038, p = 0.009) with very weak evidence for an effect on smoking initiation.
Conclusions
These findings suggest that the association between smoking, schizophrenia and depression is due, at least in part, to a causal effect of smoking, providing further evidence for the detrimental consequences of smoking on mental health.
Social protection (SP) has been demonstrated as an effective tool against poverty and severe hunger. In Ghana, SP interventions have been employed to address vulnerability to poverty since 1965. Nevertheless, its potential for enhancing nutrition has hardly been explored. To harness the cross-sectoral benefits of scaling up nutrition-sensitive actions in Ghana, the national development planning commission requested an assessment of nutrition linkages across existing SP policies and programmes. The present paper presents gaps and opportunities for improving nutrition-sensitivity of existing SP programming in Ghana. The evidence draws heavily on desk review of available published and grey literature. The data show that SP provides an entry point for mainstreaming nutrition into other programmes. However, designing and coupling SP programmes with nutrition programmes remain a challenge in Ghana. Local SP interventions are predominantly designed as standalone services and therefore are implemented independent of each other. To increase synergy between SP and nutrition, including nutrition as an explicit objective of SP policies/strategies is recommended.
Addressing contemporary nutrition problems often requires application of knowledge from multiple disciplines. The scaling up nutrition (SUN) movement harnesses multiple sectors for effective global and in-country planning and implementation. Although the role of knowledge networks (academia and research institutions) is recognised, the how of engaging knowledge networks in the current SUN architecture is only now becoming apparent. For relevant sectors to play their roles effectively, observed capacity gaps, particularly in developing country settings, need to be addressed. The present paper presents the work being undertaken by the Ghana SUN Academic Platform (AP), a local knowledge network, towards strengthening nutrition capacity in Ghana. The AP presently provides technical support, evidence and capacity towards scaling up effective nutrition interventions in Ghana and beyond. The data presented draws heavily on the observations and collective experiences of the authors in practice, complemented by a review of relevant literature. The ultimate goal of the AP is to build capacity of professionals from nutrition and cognate sectors (including planning, agriculture, health, economics, research and academia). This is an essential ingredient for effective and durable SUN efforts. The paper recognises that both disciplinary and interdisciplinary capacity is required for effective SUN efforts in Africa, and offers an approach that utilises cross-sector/inter-professional, peer-learning and experiential learning initiatives.
The western spruce budworm, Choiistoneura occidentalis Freeman, which normally passes through an obligate diapause in nature, was reared in the laboratory without diapause. The critical factor for preventing diapause appeared to be the physical environment presented to the first stage larvae. The response of C. occidentalis was flexible. The 2nd stage larvae could be made to diapause or forego diapause, depending on their rearing experience in the first stage. By eliminating diapause it was possible to rear about 7½ generations per year as against about 2¼ under normal diapause conditions. The diapause of the jack-pine budworm, C. pinus pinus Freeman, and C. lambertiana californica Powell, could be prevented by the same technique. The diapause of the spruce budworm, C. fumiferana (Clemens), could not be eliminated except after several generations of selection.
Thirteen definite and 3 probable cases of chlamydial eye infection were diagnosed in young adults attending the Bristol Eye Hospital between June 1978 and May 1980, an incidence of about 1 case per 44000 per year in the 15 to 44-year-old community served by this hospital, and 1 per 100000 in the total population of this community. These patients presented with a sub-acute follicular conjunctivitis or kerato-conjunctivitis, which had usually been present for several weeks and had often failed to respond to topical chloramphenicol treatment before presentation. Sera obtained from 14 patients all had chlamydial antibody titres of 64 or more. Over the same period of time, an estimated 2500 patients per year from the same community attended the Venereology Department at the Bristol Royal Infirmary with genital chlamydial infections. These figures suggest that chlamydial infection of the eye complicates no more than 1 in 300 chlamydial infections of the genital tract in adults.
Faeces of healthy adults and of children under the age of 5, none of whom were attending hospital or receiving antibiotics, were examined for the presence of antibiotic resistant coliform bacilli.
A higher proportion of children (67%) than of adults (46%) carried resistant strains and this difference was observed in both the rural and urban groups.
Rural members of both age groups more often carried resistant organisms than urban members. Among rural adults, the incidence of drug-resistant strains was 63 % in those whose occupation involved close contact with farm animals, compared with 29 % in those with other occupations. The survey took place before the implementation of the Swann Report could have influenced the use of antibiotics in animal foodstuffs.
Transmissible R-factors were demonstrated in 61 % of the resistant strains. The incidence of transmissible resistance was similar among adults and children in town and country.
The R-factor RP1, which carried the markers amp neo tet, confers resistance to penicillins by specifying the synthesis of Type IIIa β-lactamase. It was detected initially in a strain of Pseudomonas aeruginosa (Sykes & Richmond, 1970) and fragments spontaneously in Ps. aeruginosa strain Ps 18 to give clones which carry only the amp marker. Such clones are said to carry the element RP 1–1 since they are still capable of specifying the transfer of ampicillin and carbenicillin resistance to appropriate recipients in mating experiments. However, unlike lines carrying RP 1, they contain no detectable extrachromosomal DNA (Ingram et al. 1972), and the likely supposition is that the amp gene in these clones has become integrated into the bacterial chromosome together with the regions necessary to allow such strains to act as amp gene donors in mating experiments. It is probably cells of Ps. aeruginosa in which the amp gene has become integrated together with an RTF region that are responsible for the transfer of chromosomal markers reported by Holloway & Stanisich (1971).
This article describes the evolution of a psychosocial intervention, pairing, from its initial utilization as an interpersonally oriented therapy for severely emotionally disturbed pre- and early adolescents in a special needs school, to its current usage as a public school prevention technique for at-risk youngsters, both aggressive and withdrawn, who are living under conditions of poverty and limited community supports. The evolution of the intervention is described parallel to both the evolution of its theoretical foundations and its associated empirical analysis and evaluation. Given that our approach to both intervention and basic research is clinical-developmental (each part of the discipline influencing the other), the facilitation of greater social competence through the intervention provides the impetus for our research inquiry into the nature of psychosocial development. A generic evaluation model that integrates both outcome behavior and psychosocial development is described as it is applied to the evaluation of this specific intervention's effectiveness.
In November 1973 Newcastle disease suddenly appeared in Northern Ireland, where the viscerotropic disease had not been seen in 3½ years and the two Irelands had been regarded as largely disease free for 30 years. It was successfully controlled with only 36 confirmed affected layer flocks, plus 10 more slaughtered as ‘dangerous contacts’. Contemporary investigations failed to reveal the source of the Irish epidemic. Using archival virus samples from most of the affected flocks, RT–PCR was conducted with primers selected for all six NDV genes. Phylogenetic analyses of three genes, HN, M and F, confirmed vaccine as the cause of one of the outbreaks. The other six samples were identical and closely related to previous outbreaks in the United States and western Europe initiated by infected imported Latin American parrots. The probable cause of the epidemic followed from the importation from The Netherlands of bulk feed grains contaminated with infected pigeon faeces.
Edited by
Ervin Győri, Mathematical Institute of the Hungarian Academy of Sciences,Vera Sós, Mathematical Institute of the Hungarian Academy of Sciences
This paper begins with the observation that half of all graphs containing no induced path of length 3 are disconnected. We generalize this in several directions. First, we give necessary and sufficient conditions (in terms of generating functions) for the probability of connectedness in a suitable class of graphs to tend to a limit strictly between zero and one. Next we give a general framework in which this and related questions can be posed, involving operations on classes of finite structures. Finally, we discuss briefly an algebra associated with such a class of structures, and give a conjecture about its structure.
Introduction
The class of graphs containing no induced path of length 3 has many remarkable properties, stemming from the following well-known observation. Recall that an induced subgraph of a graph consists of a subset S of the vertex set together with all edges contained in S.
Proposition. Let G be a finite graph with more than one vertex, containing no induced path of length 3. Then G is connected if and only if its complement is disconnected.
Proof. It is trivial that the complement of a disconnected graph is connected. Moreover, since P3 is self-complementary, the property of containing no induced P3 is self-complementary. So let G be a minimal counterexample: thus, G and Ḡ are connected but, for any vertex v, either G – v or G – v is disconnected. Choose a vertex v and assume, without loss, that G - v is disconnected. Then v is joined to a vertex in each component of G – v.
This paper begins with the observation that half of all graphs containing no induced path of length 3 are disconnected. We generalize this in several directions. First, we give necessary and sufficient conditions (in terms of generating functions) for the probability of connectedness in a suitable class of graphs to tend to a limit strictly between zero and one. Next we give a general framework in which this and related questions can be posed, involving operations on classes of finite structures. Finally, we discuss briefly an algebra associated with such a class of structures, and give a conjecture about its structure.
Knowledge update has been a matter of concern to two quite separate traditions: one in philosophical logic, and another in artificial intelligence. In this paper we draw on both traditions to develop a theory of update, based on conditional logic, for a kind of knowledge base that has proven to be of interest in artificial intelligence. After motivating and formulating the logic on which our theory is based, we will prove some basic results and show how our logic can be used to describe update in an environment in which knowledge bases can be treated as truth-value assignments in four-valued logic. In keeping with Nuel Belnap's terminology in Belnap (1977a) and Belnap (1977b), we will refer to such truth-value assignments as set-ups or as four-valued set-ups.
Paraconsistency, primeness, and atomistic update
For the moment we will not say exactly what a four-valued set-up is. Instead we will describe informally some conditions under which it would be natural to structure one's knowledge base as a four-valued set-up. One of these conditions has to do with the treatment of inconsistent input; a second has to do with the representation of disjunctive information; the third concerns what kinds of statements can be the content of an update.
Inconsistent input
A logical calculus is paraconsistent if it cannot be used to derive arbitrary conclusions from inconsistent premises. Belnap argues in general terms that paraconsistent reasoning is appropriate any context where an automated reasoner must operate without any guarantee that its input is consistent, and where nondegenerate performance is desirable even if inconsistency is present. Knowledge bases used in AI applications are cases of this sort.
A chordal graph is a graph in which every cycle of length at least 4 has a chord. If G is a random n-vertex labelled chordal graph, the size of the larget clique in about n/2 and deletion of this clique almost surely leaves only isolated vertices. This gives the asymptotic number of chordal graphs and information about a variety of things such as the size of the largest clique and connectivity.
In many basic linear algebra texts it is shown that various classes of square matrices (normal, positive, invertible) possess square roots. In this note we characterize those n × n matrices with complex entries which possess at least one square root without any restriction on the class of root or matrix involved. We then use this characterization to obtain asymptotic estimates for the relative profusion of such matrices.
In Section 1 we characterize those n × n matrices with entries in C (or any algebraically complete field) which have square roots over C. This characterization is in terms of similarity classes. In Section 2 we give asymptotic estimates for the number of Jordan forms of nilpotent n × n matrices which are squares. Section 3 is given over to numerical results concerning the actual and asymptotic frequency of such forms.