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1.
Mar Pollut Bull ; 163: 111915, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33360724

ABSTRACT

The tropical waters of the Northern Arabian Gulf have a long history of maritime resource richness. High levels of biodiversity result from the complex matrix of coastal habitats, coral reefs and sea grass beds that characterise the region. Insight into the ongoing health of such habitats and the broader Kuwait maritime environment can be gauged by the status of indicator species found within these habitats. Here we review information on the occurrence, distribution and threats to key marine habitats and associated indicator species to provide an updated assessment of the state of the Kuwait's marine biodiversity. Critical evaluation of historic data highlights knowledge gaps needed inform the focus of future monitoring and conservation efforts. This assessment is designed to evaluate performance against environmental policy commitments, while providing a solid foundation for the design of comprehensive marine ecosystem management strategies.


Subject(s)
Conservation of Natural Resources , Ecosystem , Biodiversity , Coral Reefs , Kuwait
2.
Insectes Soc ; 65(4): 549-559, 2018.
Article in English | MEDLINE | ID: mdl-30416204

ABSTRACT

Understanding the ecological and environmental contexts in which eusociality can evolve is fundamental to elucidating its evolutionary origins. A sufficiently long active season is postulated to have been a key factor facilitating the transition to eusociality. Many primitively eusocial species exhibit an annual life cycle, which is thought to preclude the expression of eusociality where the active season is too short to produce successive worker and reproductive broods. However, few studies have attempted to test this idea experimentally. We investigated environmental constraints on the expression of eusociality in the obligate primitively eusocial sweat bee Lasioglossum malachurum, by transplanting nest foundresses from the south to the far north of the United Kingdom, far beyond the natural range of L. malachurum. We show that transplanted bees can exhibit eusociality, but that the short length of the season and harsher environmental conditions could preclude its successful expression. In one year, when foundresses were transplanted only after provisioning first brood (B1) offspring, workers emerged in the north and provisioned a second brood (B2) of reproductives. In another year, when foundresses were transplanted prior to B1 being provisioned, they were just as likely to initiate nesting and provisioned just as many B1 cells as foundresses in the south. However, the life cycle was delayed by approximately 7 weeks and nests suffered 100% B1 mortality. Our results suggest that short season length together with poor weather conditions represent an environmental barrier to the evolution and expression of eusociality in sweat bees.

3.
Behav Ecol Sociobiol ; 72(3): 56, 2018.
Article in English | MEDLINE | ID: mdl-29568150

ABSTRACT

ABSTRACT: Eusociality is characterised by a reproductive division of labour, where some individuals forgo direct reproduction to instead help raise kin. Socially polymorphic sweat bees are ideal models for addressing the mechanisms underlying the transition from solitary living to eusociality, because different individuals in the same species can express either eusocial or solitary behaviour. A key question is whether alternative social phenotypes represent environmentally induced plasticity or predominantly genetic differentiation between populations. In this paper, we focus on the sweat bee Lasioglossum calceatum, in which northern or high-altitude populations are solitary, whereas more southern or low-altitude populations are typically eusocial. To test whether social phenotype responds to local environmental cues, we transplanted adult females from a solitary, northern population, to a southern site where native bees are typically eusocial. Nearly all native nests were eusocial, with foundresses producing small first brood (B1) females that became workers. In contrast, nine out of ten nests initiated by transplanted bees were solitary, producing female offspring that were the same size as the foundress and entered directly into hibernation. Only one of these ten nests became eusocial. Social phenotype was unlikely to be related to temperature experienced by nest foundresses when provisioning B1 offspring, or by B1 emergence time, both previously implicated in social plasticity seen in two other socially polymorphic sweat bees. Our results suggest that social polymorphism in L. calceatum predominantly reflects genetic differentiation between populations, and that plasticity is in the process of being lost by bees in northern populations. SIGNIFICANCE STATEMENT: Phenotypic plasticity is thought to play a key role in the early stages of the transition from solitary to eusocial behaviour, but may then be lost if environmental conditions become less variable. Socially polymorphic sweat bees exhibit either solitary or eusocial behaviour in different geographic populations, depending on the length of the nesting season. We tested for plasticity in the socially polymorphic sweat bee Lasioglossum calceatum by transplanting nest foundresses from a northern, non-eusocial population to a southern, eusocial population. Plasticity would be detected if transplanted bees exhibited eusocial behaviour. We found that while native bees were eusocial, 90% of transplanted bees and their offspring did not exhibit traits associated with eusociality. Environmental variables such as time of offspring emergence or temperatures experienced by foundresses during provisioning could not explain these differences. Our results suggest that the ability of transplanted bees to express eusociality is being lost, and that social polymorphism predominantly reflects genetic differences between populations.

4.
J Fish Biol ; 89(3): 1782-93, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27465299

ABSTRACT

This paper presents the first phase in the development and validation of a simple and reliable environmental (e)DNA method using conventional PCR to detect four species of non-native freshwater fish: pumpkinseed Lepomis gibbosus, sunbleak Leucaspius delineatus, fathead minnow Pimephales promelas and topmouth gudgeon Pseudorasbora parva. The efficacy of the approach was demonstrated in indoor tank (44 l) trials in which all four species were detected within 24 h. Validation was through two field trials, in which L. gibbosus was detected 6-12 h after its introduction into outdoor experimental ponds and P. parva was successfully detected in disused fish rearing ponds where the species was known to exist. Thus, the filtration of small (30 ml) volumes of pond water was sufficient to capture fish eDNA and the approach emphasised the importance of taking multiple water samples of sufficient spatial coverage for detecting species of random or patchy distribution.


Subject(s)
Environmental Monitoring/methods , Fishes/classification , Fishes/genetics , Introduced Species , Ponds/analysis , Animals , Cyprinidae/classification , Cyprinidae/genetics , DNA/genetics , Perciformes/classification , Perciformes/genetics , Reproducibility of Results , Species Specificity
5.
Insectes Soc ; 63: 327-338, 2016.
Article in English | MEDLINE | ID: mdl-27340290

ABSTRACT

Temperate-zone socially polymorphic sweat bees (Hymenoptera: Halictidae) are ideal model systems for elucidating the origins of eusociality, a major evolutionary transition. Bees express either social or solitary behaviour in different parts of their range, and social phenotype typically correlates with season length. Despite their obvious utility, however, socially polymorphic sweat bees have received relatively little attention with respect to understanding the origins of eusociality. Lasioglossum (Evylaeus) calceatum is a widespread sweat bee that is thought to be socially polymorphic, with important potential as an experimental model species. We first determined the social phenotype of L. calceatum at three sites located at different latitudes within the UK. We then investigated sociality in detail across two years at the southernmost site. We found that L. calceatum exhibits latitudinal social polymorphism within the UK; bees were solitary at our two northern sites but the majority of nests were social at our southern site. Sociality in the south was characterised by a relatively small mean of two and 3.5 workers per nest in each year, respectively, and a small to medium mean caste-size dimorphism of 6.6 %. Foundresses were smaller in our more northern and high altitude populations. Sociality is clearly less specialised than in some closely related obligately social species but probably more specialied than other polymorphic sweat bees. Our research provides a starting point for future experimental work to investigate mechanisms underlying social polymorphism in L. calceatum.

7.
J Fish Biol ; 85(4): 1042-59, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25052817

ABSTRACT

The downstream migratory behaviour of wild Atlantic salmon Salmo salar smolts was monitored using passive integrated transponder (PIT) antennae systems over 10 years in the lower reaches of a small chalk stream in southern England, U.K. The timing of smolt movements and the likely occurrence of schooling were investigated and compared to previous studies. In nine of the 10 consecutive years of study, the observed diel downstream patterns of S. salar smolt migration appeared to be synchronized with the onset of darkness. The distribution of time intervals between successive nocturnal detections of PIT-tagged smolts was as expected if generated randomly from observed hourly rates. There were, however, significantly more short intervals than expected for smolts detected migrating during the day. For each year from 2006 to 2011, the observed 10th percentile of the daytime intervals was <4 s, compared to ≥55 s for the simulated random times, indicating greater incidence of groups of smolts. Groups with the shortest time intervals between successive PIT tag detections originated from numerous parr tagging sites (used as a proxy for relatedness). The results suggest that the ecological drivers influencing daily smolt movements in the lower reaches of chalk stream catchments are similar to those previously reported at the onset of migration for smolts leaving their natal tributaries; that smolts detected migrating during the night are moving independently following initiation by a common environmental factor (presumably darkness), whereas those detected migrating during the day often move in groups, and that such schools may not be site (kin)-structured. The importance of understanding smolt migratory behaviour is considered with reference to stock monitoring programmes and enhancing downstream passage past barriers.


Subject(s)
Animal Migration , Photoperiod , Salmo salar/physiology , Animal Identification Systems , Animals , England , Rivers
8.
Persoonia ; 31: 188-296, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24761043

ABSTRACT

Novel species of microfungi described in the present study include the following from South Africa: Camarosporium aloes, Phaeococcomyces aloes and Phoma aloes from Aloe, C. psoraleae, Diaporthe psoraleae and D. psoraleae-pinnatae from Psoralea, Colletotrichum euphorbiae from Euphorbia, Coniothyrium prosopidis and Peyronellaea prosopidis from Prosopis, Diaporthe cassines from Cassine, D. diospyricola from Diospyros, Diaporthe maytenicola from Maytenus, Harknessia proteae from Protea, Neofusicoccum ursorum and N. cryptoaustrale from Eucalyptus, Ochrocladosporium adansoniae from Adansonia, Pilidium pseudoconcavum from Greyia radlkoferi, Stagonospora pseudopaludosa from Phragmites and Toxicocladosporium ficiniae from Ficinia. Several species were also described from Thailand, namely: Chaetopsina pini and C. pinicola from Pinus spp., Myrmecridium thailandicum from reed litter, Passalora pseudotithoniae from Tithonia, Pallidocercospora ventilago from Ventilago, Pyricularia bothriochloae from Bothriochloa and Sphaerulina rhododendricola from Rhododendron. Novelties from Spain include Cladophialophora multiseptata, Knufia tsunedae and Pleuroascus rectipilus from soil and Cyphellophora catalaunica from river sediments. Species from the USA include Bipolaris drechsleri from Microstegium, Calonectria blephiliae from Blephilia, Kellermania macrospora (epitype) and K. pseudoyuccigena from Yucca. Three new species are described from Mexico, namely Neophaeosphaeria agaves and K. agaves from Agave and Phytophthora ipomoeae from Ipomoea. Other African species include Calonectria mossambicensis from Eucalyptus (Mozambique), Harzia cameroonensis from an unknown creeper (Cameroon), Mastigosporella anisophylleae from Anisophyllea (Zambia) and Teratosphaeria terminaliae from Terminalia (Zimbabwe). Species from Europe include Auxarthron longisporum from forest soil (Portugal), Discosia pseudoartocreas from Tilia (Austria), Paraconiothyrium polonense and P. lycopodinum from Lycopodium (Poland) and Stachybotrys oleronensis from Iris (France). Two species of Chrysosporium are described from Antarctica, namely C. magnasporum and C. oceanitesii. Finally, Licea xanthospora is described from Australia, Hypochnicium huinayensis from Chile and Custingophora blanchettei from Uruguay. Novel genera of Ascomycetes include Neomycosphaerella from Pseudopentameris macrantha (South Africa), and Paramycosphaerella from Brachystegia sp. (Zimbabwe). Novel hyphomycete genera include Pseudocatenomycopsis from Rothmannia (Zambia), Neopseudocercospora from Terminalia (Zambia) and Neodeightoniella from Phragmites (South Africa), while Dimorphiopsis from Brachystegia (Zambia) represents a novel coelomycetous genus. Furthermore, Alanphillipsia is introduced as a new genus in the Botryosphaeriaceae with four species, A. aloes, A. aloeigena and A. aloetica from Aloe spp. and A. euphorbiae from Euphorbia sp. (South Africa). A new combination is also proposed for Brachysporium torulosum (Deightoniella black tip of banana) as Corynespora torulosa. Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.

9.
Sci Total Environ ; 409(19): 3993-4009, 2011 Sep 01.
Article in English | MEDLINE | ID: mdl-21703662

ABSTRACT

Multiple demands are placed on farming systems today. Society, national legislation and market forces seek what could be seen as conflicting outcomes from our agricultural systems, e.g. food quality, affordable prices, a healthy environmental, consideration of animal welfare, biodiversity etc., Many of these demands, or desirable outcomes, are interrelated, so reaching one goal may often compromise another and, importantly, pose a risk to the economic viability of the farm. SIMS(DAIRY), a farm-scale model, was used to explore this complexity for dairy farm systems. SIMS(DAIRY) integrates existing approaches to simulate the effect of interactions between farm management, climate and soil characteristics on losses of nitrogen, phosphorus and carbon. The effects on farm profitability and attributes of biodiversity, milk quality, soil quality and animal welfare are also included. SIMS(DAIRY) can also be used to optimise fertiliser N. In this paper we discuss some limitations and strengths of using SIMS(DAIRY) compared to other modelling approaches and propose some potential improvements. Using the model we evaluated the sustainability of organic dairy systems compared with conventional dairy farms under non-optimised and optimised fertiliser N use. Model outputs showed for example, that organic dairy systems based on grass-clover swards and maize silage resulted in much smaller total GHG emissions per l of milk and slightly smaller losses of NO(3) leaching and NO(x) emissions per l of milk compared with the grassland/maize-based conventional systems. These differences were essentially because the conventional systems rely on indirect energy use for 'fixing' N compared with biological N fixation for the organic systems. SIMS(DAIRY) runs also showed some other potential benefits from the organic systems compared with conventional systems in terms of financial performance and soil quality and biodiversity scores. Optimisation of fertiliser N timings and rates showed a considerable scope to reduce the (GHG emissions per l milk too).


Subject(s)
Dairying , Models, Theoretical , Organic Agriculture/methods , Carbon Footprint , Fertilizers , Nitrogen , Soil/chemistry , United Kingdom
11.
Sci Total Environ ; 344(1-3): 15-25, 2005 May 15.
Article in English | MEDLINE | ID: mdl-15907507

ABSTRACT

Erosive storm energy is the primary driver of soil detachment, and hence a major determinant of transfer of sediment and particulate phosphorus (P) to surface waters. Modelling of sediment and P loss at catchment scale, for example for the development of catchment and national mitigation policies, requires a spatially interpolated estimate of variation in erosion risk. To this end we present a method of estimating total rainfall erosivity, as kinetic energy (KE), for any location in England and Wales, from daily rainfall data or monthly climate data. Analysis of detailed, high-resolution records from eleven contrasting sites showed strong predictive correlations between daily rainfall quantity and associated daily total kinetic energy estimated from hourly rainfall intensities. The coefficients showed systematic seasonal variation, with greatest KE per unit of rainfall in late summer and autumn months. In contrast, no systematic spatial variation was found as a function of location or continentality index. The relationships were integrated with probability distributions of rainfall quantity per rain day derived from spatial climate data (monthly rainfall totals and numbers of rain days). The resulting map captures and quantifies the effects of rainfall quantity and intensity patterns on risk of sediment detachment, and as such provides a critical input layer to catchment-scale models of sediment and P transfer.


Subject(s)
Fresh Water/chemistry , Geologic Sediments/chemistry , Phosphorus/analysis , Rain , Water Pollutants, Chemical/analysis , England , Models, Theoretical , Wales , Water Movements
12.
J Laryngol Otol ; 119(2): 129-31, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15832470

ABSTRACT

The authors describe a novel use of a de-epithelialized deltopectoral flap for the closure of tracheo-oesophageal fistulae, which have been resistant to other methods of closure.


Subject(s)
Plastic Surgery Procedures/methods , Surgical Flaps , Tracheoesophageal Fistula/surgery , Humans , Laryngectomy , Larynx, Artificial , Postoperative Complications/surgery , Tracheoesophageal Fistula/etiology
14.
Br J Plast Surg ; 55(5): 387-9, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12372366

ABSTRACT

There are numerous theories concerning the aetiology of chondrodermatitis, and many authors have suggested that pressure is a significant factor. We prospectively gathered information from 14 patients with a clinical diagnosis of this condition. Many of the patients had a physical condition that forced them to lie on the side of the affected ear. Patients were advised to use protective padding of the ear at night. Most patients were rapidly relieved of their symptoms, although healing was frequently prolonged. This positive response rate and the high recurrence rate after surgery suggest that this condition should be primarily treated conservatively; they also support the theory that pressure on the ear is the main aetiological factor. Biopsies in two patients who did not respond to conservative treatment led to an altered diagnosis.


Subject(s)
Cartilage Diseases/therapy , Dermatitis/therapy , Ear Diseases/therapy , Ear Protective Devices , Adult , Aged , Aged, 80 and over , Ear Cartilage , Ear, External , Female , Humans , Male , Middle Aged , Prospective Studies , Recurrence
15.
Nature ; 418(6894): 203-6, 2002 Jul 11.
Article in English | MEDLINE | ID: mdl-12110893

ABSTRACT

Plant stress caused by extreme environmental conditions is already a principal reason for yield reduction in crops. The threat of global environment change makes it increasingly important to generate crop plants that will withstand such conditions. Stress, particularly stress caused by increased sunlight, leads to the production of reactive oxygen species that cause photo-oxidative cell damage. Carotenoids, which are present in the membranes of all photosynthetic organisms, help protect against such light-dependent oxidative damage. In plants, the xanthophyll cycle (the reversible interconversion of two carotenoids, violaxanthin and zeaxanthin) has a key photoprotective role and is therefore a promising target for genetic engineering to enhance stress tolerance. Here we show that in Arabidopsis thaliana overexpression of the chyB gene that encodes beta-carotene hydroxylase--an enzyme in the zeaxanthin biosynthetic pathway--causes a specific twofold increase in the size of the xanthophyll cycle pool. The plants are more tolerant to conditions of high light and high temperature, as shown by reduced leaf necrosis, reduced production of the stress indicator anthocyanin and reduced lipid peroxidation. Stress protection is probably due to the function of zeaxanthin in preventing oxidative damage of membranes.


Subject(s)
Arabidopsis/enzymology , Arabidopsis/physiology , Heat-Shock Response , Mixed Function Oxygenases/metabolism , Oxidative Stress , Anthocyanins/analysis , Arabidopsis/cytology , Arabidopsis/genetics , Carotenoids/metabolism , Darkness , Gene Expression , Hot Temperature , Light , Lipid Peroxidation , Malondialdehyde/metabolism , Mixed Function Oxygenases/genetics , Necrosis , Photosynthesis , Plant Leaves/physiology , RNA, Plant/genetics , RNA, Plant/metabolism , Xanthophylls/metabolism , Zeaxanthins , beta Carotene/analogs & derivatives , beta Carotene/metabolism
16.
Br J Plast Surg ; 55(3): 256-7, 2002 Apr.
Article in English | MEDLINE | ID: mdl-12041983

ABSTRACT

Five cases of cleft palate with interalveolar synechiae have been previously reported. This is the first report of siblings with this condition, and suggests a genetic aetiology. These patients present with an inability to open the mouth adequately. Initial management is directed towards dividing the intraoral adhesions, which may cause significant problems of airway management. Significantly, the intraoral adhesions resolved spontaneously in one of our patients. This, to our knowledge, has not been reported before.


Subject(s)
Mouth Abnormalities/surgery , Alveolar Process , Cleft Palate/genetics , Cleft Palate/surgery , Genes, Dominant , Humans , Infant, Newborn , Male , Mouth Abnormalities/genetics , Nuclear Family , Syndrome , Tissue Adhesions
17.
Br J Anaesth ; 88(1): 139-40, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11881870

ABSTRACT

We report two patients who developed skin necrosis following an intramuscular injection of non-steroidal anti-inflammatory drug into the anteriolateral area of their thigh. Both patients required further multiple operations and one developed life threatening septicaemia. They were left with disfiguring scars. Skin necrosis, although rare, is a recognized adverse reaction to intramuscular non-steroidal anti-inflammatory injections. It is likely that the injections were, unwittingly, administered subcutaneously. It is important to ensure intra-muscular administration, with an appropriate needle length.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Skin/pathology , Adult , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Female , Humans , Injections, Intramuscular , Male , Necrosis
19.
Can J Anaesth ; 47(1): 10-9, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10626712

ABSTRACT

PURPOSE: Recently, the American College of Cardiology - American Heart Association (ACC-AHA) published guidelines and an associated algorithm for preoperative cardiovascular evaluation of patients undergoing non-cardiac surgery. Our purpose was to (i) test guideline's ability to predict adverse cardiac events within seven days after surgery, (ii) determine whether medical clinical predictors or surgical risks was a better predictor of cardiac events. METHODS: Retrospective review of 119 cardiology and anesthesia consultations over 15 mo, ending March 31, 1998. Patients were classified into their respective medical clinical predictor and surgical risk groups, as outlined in ACC-AHA guidelines. Associations between the medical predictor and surgical risk scores and adverse cardiac outcomes were quantified via multiple logistic regression analysis. Two outcomes were employed. Outcome I, included: myocardial infarction/ischemia; angina; congestive heart failure, arrhythmia or death. Outcome 2 expanded the definition to include "cancellation of surgery due to cardiac risk" as a negative cardiac outcome. RESULTS: Diabetes, Canadian Cardiovascular Class (CCS) III or IV angina, and MI within six months before surgery were strongly associated with the two cardiac outcomes. For outcome 1 and 2, medical predictors and surgical risks, considered simultaneously, performed with a sensitivity of 93% and specificity of 46-51%. When considered separately, major clinical medical predictors had a sensitivity of 87-89%, while surgical risks showed a specificity of 89% in predicting the two outcomes. CONCLUSION: Medical predictors in ACC-AHA classification scheme were highly sensitive whereas surgical risks were more specific in predicting adverse post-operative cardiac events. Prospective study is needed to confirm these observations.


Subject(s)
Heart Diseases/etiology , Postoperative Complications/etiology , Adult , Aged , Aged, 80 and over , Female , Guidelines as Topic , Humans , Male , Middle Aged , Regression Analysis , Retrospective Studies , Risk
20.
J Psychosom Res ; 47(1): 93-103, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10511424

ABSTRACT

We studied ten patients referred from the neurology service with severe disability associated with the use of a wheelchair, but with no organic disorder to account for their disabilities. All patients were assessed using rating scales as well as a standardized psychiatric interview (SCID), and all medical and psychiatric case notes were examined. We also interviewed key carers for their views on the information and assistance the patients had received. All but two of the ten patients were women, and the mean age was 45.4 years (SD=5.4). All had current diagnoses of conversion or somatoform disorders and six had previous episodes of major depression. Most patients expressed beliefs about their illness that were not consistent with the medical facts, and only two of the carers were satisfied with explanations they had been given by doctors. The results suggest that requests for psychiatric help once patients have become grossly disabled are unlikely to lead to recovery. The psychiatrist, however, can help the primary care doctor to formulate a plan of management aimed at preventing further deterioration.


Subject(s)
Attitude to Health , Disabled Persons/psychology , Somatoform Disorders/psychology , Wheelchairs , Adult , Caregivers/psychology , Child , Child Abuse/psychology , Child Rearing , Chronic Disease , Female , Humans , Male , Middle Aged , Sick Role , Somatoform Disorders/etiology
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