An approach to the patient with a post-nasal drip and rhinosinusitis

Post-nasal drip (PND) can be a bothersome symptom and one of the main reasons for patients visiting a general practitioner (GP), pulmonologist or ear, nose and throat (ENT) surgeon. It can be either a symptom, sometimes not appreciated by the examining practitioner, or an important clinical sign suggesting rhinosinusitis. This article aims to explain the aetiological factors and initial work-up of the patient with a PND and rhinosinusitis and suggest a treatment paradigm for practitioners

Effects of greywater irrigation on germination, growth and photosynthetic characteristics in selected African leafy vegetables

The reuse of greywater, wastewater from sources other than toilets, could enable low-income  households to save potable water for drinking and cooking. Greywater irrigation of food crops is widely practised but its effects on African leafy vegetables (ALVs), which hold potential for cultivation to improve food security, are unknown. This study investigated the effects of synthetic greywater  irrigation on germination in three ALVs, viz., Amaranthus dubius, Cleome gynandra and Solanum nigrum, and subsequent seedling growth in A. dubius and S. nigrum. Seeds and seedlings were treated with chlorinated and dechlorinated greywater and tap water, supplemented with nutrients. Greywater application decreased germination capacity (by 23–25%) when assessed in Petri dishes in A. dubius only. However, greywater application was less harmful to A. dubius seeds sown in soil. Vigour was compromised in greywater-treated seeds of all three species but greywater can be used to irrigate freshly-sown seeds of A. dubius without reducing percentage seedling production. However, greywater irrigation reduced capacity (by 21–23%) and rate of shoot emergence in S. nigrum, and growth and chlorophyll content in both species. These negative effects were accompanied by increased soil  electrical conductivity (after 21 d) and pH (after 14 d). The reduced growth under greywater irrigation was most likely based on a reduction in light-harvesting capacity and/or nutrient availability. Overall, S. nigrum seedlings were significantly more sensitive to the negative effects of greywater, possibly due to increased transpirational water loss under greywater irrigation. The effects of greywater were largely independent of chlorine content. Applying greywater in excess of plant requirements and/or alternating greywater irrigation events with freshwater watering events could promote leaching of salts found in greywater. The effects of greywater irrigation on soil water and nutrient availability demand further investigation for ALVs.Keywords: African leafy vegetables, greywater irrigation, germination, seedling growt

Allergic fungal sinusitis secondary to Acremonium species causing unilateral visual loss

A wide range of fungi have been associated with Allergic Fungal Sinusitis (AFS) or Eosinophilic fungal rhinosinusitis ( EFRS) as it is known in some institutions. To our knowledge, this is the first reported case of aggressive, invasive AFS due to Acremonium species occurring in an immunocompetent patient and leading to unilateral visual loss. Literature on AFS is reviewed.Key words: Eosinophilic fungal rhinosinusitis, Allergic fungal sinusitis, Acremonium species, visual loss

TOR1A mutation-related isolated childhood-onset generalised dystonia in South Africa

Background. Childhood-onset generalised dystonia is commonly caused by TOR1A mutations and is known to respond well to pallidal deep-brain stimulation (DBS) surgery. The incidence and prevalence of monogenic dystonia in individuals from Africa and specifically of African ancestry are unknown, and no local cases of TOR1A mutation dystonia are found in the literature.Objectives. To describe our experience with the outcome of TOR1A mutation-positive patients with isolated generalised dystonia (IGD) of childhood onset who were treated with pallidal DBS.Methods. All patients with TOR1A mutations from Steve Biko Academic Hospital and the Pretoria Neurology Institute in Pretoria, South Africa (SA), who underwent DBS for IGD of childhood onset were identified. We conducted a retrospective analysis of their demographics, clinical presentation and time to generalisation, genetic status and family history, and response to DBS treatment of the internal segment of the globus pallidus (GPi), utilising pre- and post-surgical scores of the United Dystonia Rating Scale (UDRS).Results. Three patients, all of black African ancestry, were identified. The median age at onset was 12 years and the median time to surgery from dystonia generalisation was 3 years. Two children presented with cervical-onset dystonia. Two patients were related, representing the only two with a positive family history. All three patients had a positive outcome after surgery, with improvement of 67 - 90% on the UDRS recorded at last follow-up.Conclusions. TOR1A mutations are found in SA patients of black African ancestry, with age of onset and generalisation comparable to those described in international studies. However, onset with cervical dystonia was more common than previously reported. Response to GPi DBS was excellent in all patients.

A new distribution record of Chambardia wahlbergi (Krauss, 1848) (Bivalvia: Iridinidae) and Unio caffer (Krauss, 1848) (Bivalvia: Unionidae) in South Africa

Little is known with regard to the conservation status of invertebrates of South Africa; however, in the revised edition of the IUCN Red Data List (2011) the conservation status of both Unio caffer and Chambardia wahlbergi is considered as ‘of least concern’. In recent reports on the geographical distribution and habitat preferences of these two species in South Africa, concern was expressed regarding their conservation status. However, specimens of C. wahlbergi collected at several sites on several occasions in the Vaal River were the first evidence that the geographical distribution of this bivalve was wider and not restricted to water bodies located in east-flowing catchments in the warmer areas of South Africa. The fact that populations of C. wahlbergi can become established in habitats on the Highveld was further supported by a number of valves collected on the dry bed of the Schoonspruit (26° 37’ 55.2”S, 26° 35’ 32.3”E), near Klerksdorp in the North West Province, on 16 February 2016. A number of valves of U. caffer which were collected on the same occasion at the same locality are also the first record of this species from this water body

Endogenous orienting modulates the Simon effect: critical factors in experimental design

Responses are faster when the side of stimulus and response correspond than when they do not correspond, even if stimulus location is irrelevant to the task at hand: the correspondence, spatial compatibility effect, or Simon effect. Generally, it is assumed that an automatically generated spatial code is responsible for this effect, but the precise mechanism underlying the formation of this code is still under dispute. Two major alternatives have been proposed: the referential-coding account, which can be subdivided into a static version and an attention-centered version, and the attention-shift account. These accounts hold clear-cut predictions for attentional cuing experiments. The former would assume a Simon effect irrespective of attentional cuing in its static version, whereas the attention-centered version of the referential-coding account and the attention-shift account would predict a decreased Simon effect on validly as opposed to invalidly cued trials. However, results from previous studies are equivocal to the effects of attentional cuing on the Simon effect. We argue here that attentional cueing reliably modulates the Simon effect if some crucial experimental conditions, mostly relevant for optimizing attentional allocation, are met. Furthermore, we propose that the Simon effect may be better understood within the perspective of supra-modal spatial attention, thereby providing an explanation for observed discrepancies in the literature

Tracheal stenosis: Preventable morbidity on the increase in our intensive care units

Following a marked increase in patients with tracheal stenosis at Groote Schuur Hospital, we re-examined this problem to identify new trends. Practitioners should be aware of this problem and that tracheal stenosis is an avoidable complication of endotracheal (ET) intubation. It is invariably difficult to treat, a heavy treatment burden and has an associated significant morbidity and reduction in quality of life. A 10-year retrospective review of patients that presented with or were referred to our service with tracheal stenosis showed no new patterns to be responsible for the increase incidence of stenosis. Therefore we conducted a survey of endotracheal tube (ETT) cuff pressures and cuff monitoring practises in local intensive care units (ICUs). This revealed that cuff pressures were dangerously elevated in 30% of all intubated patients surveyed in the ICUs. We are concerned that poor cuff pressure monitoring practises may be responsible for the increase in tracheal stenosis

The energetic significance of communal roosting and insulated roost nests in a small arid-zone passerine

Small endotherms have evolved behavioural mechanisms for reducing rest-phase energy expenditure, which reduce the likelihood of mismatches between energy supply and demand during periods of cold weather and/or food scarcity. Although the energetic consequences of communal roosting and the use of insulated roosts have been the subject of numerous studies, less is known about the energy savings achieved by species that use these two behaviours simultaneously. We hypothesised that communal roosting in insulated roost nests by a small arid-zone passerine, the Scaly-feathered Finch Sporopipes squamifrons, results in additive energetic benefits that reduce nocturnal energy requirements far below those of individual birds roosting in the open. We measured metabolic rates in finches over air temperatures (Ta) between −5 and 20 °C using flow-through respirometry. Measurements were taken from single finches and groups varying in size from two to 12 individuals, with or without a roost nest. Consistent with our predictions, rest-phase resting metabolic rate (RMR) of finches decreased when the birds roosted communally and decreased further when groups were roosting in a nest. In the absence of a nest, groups of eight or 12 birds reduced RMR by >30% compared with single birds. These energy savings increased further when groups roosted in nests; at Ta = 0 °C, groups of eight or 12 finches approximately halved their RMR compared with that of groups without nests. Our data confirm that Scaly-feathered Finches save considerable energy by roosting communally in roost nests, and these behaviours likely are a key reason why this small species from subtropical latitudes can occur in areas with winter night-time temperatures as low as −10 °C.Les petites endothermes ont développé des mécanismes comportementaux pour réduire les dépenses énergétiques en phase de repos, ce qui réduit le risque de déséquilibre entre l’offre et la demande en énergie pendant les périodes de froid et / ou de pénurie alimentaire. Bien que les conséquences énergétiques des dortoirs collectifs et de l’utilisation de nids-gîtes isolés aient fait l’objet de nombreuses études, on en sait moins sur les économies d’énergie réalisées par les espèces qui utilisent simultanément ces deux comportements. Nous avons émis l’hypothèse que les dortoirs collectifs dans les nids-gîtes isolés par un petit passereau de la zone aride, le Sporopipe squameux Sporopipes squamifrons, entraîne des avantages énergétiques supplémentaires qui réduisent les besoins énergétiques nocturnes bien inférieurs à ceux des oiseaux individuels dormant à l’air libre. Nous avons mesuré les taux métaboliques chez ces tisserins à des températures de l’air (Ta) comprises entre −5 et 20 ° C en utilisant une respirométrie à flux continu. Les mesures ont été prises à partir d’oiseaux isolés et d’oiseaux groupés de taille variable allant de deux à 12 individus, avec ou sans gîte. Conformément à nos prévisions, le taux métabolique de repos (TMR) des Sporopipe au repos (phase de repos) a diminué lorsque les oiseaux se sont rassemblés en groupe et a encore diminué lorsque des groupes dormaient dans un nid. En l’absence de nid, des groupes de huit ou 12 oiseaux ont réduit le TMR de >30% par rapport aux oiseaux isolés. Ces économies d’énergie ont encore augmenté lorsque des groupes gîtent dans des nids; à Ta = 0 °C, les groupes de huit ou 12 Sporopipe ont approximativement réduit de moitié leur TMR par rapport aux groupes sans nids. Nos données confirment que les Sporopipe squameux économisent une énergie considérable en dormant ensemble dans des nids-gîtes, et que ces comportements sont probablement une des principales raisons pour lesquelles cette petite espèce de latitudes subtropicales peut être présente dans des zones où les températures nocturnes sont aussi basses que −10 °C.The DST-NRF Centre of Excellence at the FitzPatrick Institute and the University of Pretoria. This work is also based on research supported in part by the National Research Foundation of South Africa (grant number 110506).https://www.tandfonline.com/loi/tost202019-12-20hj2019Zoology and Entomolog

Fractal Holography: a geometric re-interpretation of cosmological large scale structure

The fractal dimension of large-scale galaxy clustering has been demonstrated to be roughly $D_F \sim 2$ from a wide range of redshift surveys. If correct, this statistic is of interest for two main reasons: fractal scaling is an implicit representation of information content, and also the value itself is a geometric signature of area. It is proposed that the fractal distribution of galaxies may thus be interpreted as a signature of holography (``fractal holography''), providing more support for current theories of holographic cosmologies. Implications for entropy bounds are addressed. In particular, because of spatial scale invariance in the matter distribution, it is shown that violations of the spherical entropy bound can be removed. This holographic condition instead becomes a rigid constraint on the nature of the matter density and distribution in the Universe. Inclusion of a dark matter distribution is also discussed, based on theoretical considerations of possible universal CDM density profiles.Comment: 13 pp, LaTeX. Revised version; to appear in JCA

Statistical mechanics of image restoration and error-correcting codes

We develop a statistical-mechanical formulation for image restoration and error-correcting codes. These problems are shown to be equivalent to the Ising spin glass with ferromagnetic bias under random external fields. We prove that the quality of restoration/decoding is maximized at a specific set of parameter values determined by the source and channel properties. For image restoration in mean-field system a line of optimal performance is shown to exist in the parameter space. These results are illustrated by solving exactly the infinite-range model. The solutions enable us to determine how precisely one should estimate unknown parameters. Monte Carlo simulations are carried out to see how far the conclusions from the infinite-range model are applicable to the more realistic two-dimensional case in image restoration.Comment: 20 pages, 9 figures, ReVTe