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A terrestrial (lacustrine and fluvial) palaeoclimate record from Hoxne (Suffolk, UK) shows two temperate phases separated by a cold episode, correlated with MIS 11 subdivisions corresponding to isotopic events 11.3 (Hoxnian interglacial period), 11.24 (Stratum C cold interval), and 11.23 (warm interval with evidence of human presence). A robust, reproducible multiproxy consensus approach validates and combines quantitative palaeotemperature reconstructions from three invertebrate groups (beetles, chironomids, and ostracods) and plant indicator taxa with qualitative implications of molluscs and small vertebrates. Compared with the present, interglacial mean monthly air temperatures were similar or up to 4.0°C higher in summer, but similar or as much as 3.0°C lower in winter; the Stratum C cold interval, following prolonged nondeposition or erosion of the lake bed, experienced summers 2.5°C cooler and winters between 5°C and 10°C cooler than at present. Possible reworking of fossils into Stratum C from underlying interglacial assemblages is taken into account. Oxygen and carbon isotopes from ostracod shells indicate evaporatively enriched lake water during Stratum C deposition. Comparative evaluation shows that proxy-based palaeoclimate reconstruction methods are best tested against each other and, if validated, can be used to generate more refined and robust results through multiproxy consensus.
The Mediterranean diet has been reported to be inversely associated with incident metabolic syndrome (MetSyn) among older adults; however, this association has not been studied in young African American and white adults. The objective of the present study was to evaluate the association of a modified Mediterranean diet (mMedDiet) score with the 25-year incidence of the MetSyn in 4713 African American and white adults enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study. A diet history questionnaire was used to assess dietary intake at baseline, year 7 and year 20 and a mMedDiet score was created. Cardiovascular risk factors were measured at multiple examinations over 25 years. The MetSyn was defined according to the National Cholesterol Education Program Adult Treatment Panel III (ATP III) criteria. Cox proportional-hazards regression analysis was use to evaluate associations for incident MetSyn across the mMedDiet score categories adjusting for demographic characteristics, lifestyle factors and BMI. Higher mMedDiet scores represented adherence to a dietary pattern rich in fruit, vegetables, whole grains, nuts and fish, but poor in red and processed meat and snack foods. The incidence of MetSyn components (abdominal obesity, elevated TAG concentrations and low HDL-cholesterol concentrations) was lower in those with higher mMedDiet scores than in those with lower scores. Furthermore, the incidence of the MetSyn was lower across the five mMedDiet score categories; the hazard ratios and 95 % CI from category 1 to category 5 were 1·0; 0·94 (0·76, 1·15); 0·84 (0·68, 1·04); 0·73 (0·58, 0·92); and 0·72 (0·54, 0·96), respectively (Ptrend= 0·005). These findings suggest that the risk of developing the MetSyn is lower when consuming a diet rich in fruit, vegetables, whole grains, nuts and fish.
In the static analysis of functional programs, pushdown flow analysis and abstract garbage collection push the boundaries of what we can learn about programs statically. This work illuminates and poses solutions to theoretical and practical challenges that stand in the way of combining the power of these techniques. Pushdown flow analysis grants unbounded yet computable polyvariance to the analysis of return-flow in higher-order programs. Abstract garbage collection grants unbounded polyvariance to abstract addresses which become unreachable between invocations of the abstract contexts in which they were created. Pushdown analysis solves the problem of precisely analyzing recursion in higher-order languages; abstract garbage collection is essential in solving the “stickiness” problem. Alone, our benchmarks demonstrate that each method can reduce analysis times and boost precision by orders of magnitude. We combine these methods. The challenge in marrying these techniques is not subtle: computing the reachable control states of a pushdown system relies on limiting access during transition to the top of the stack; abstract garbage collection, on the other hand, needs full access to the entire stack to compute a root set, just as concrete collection does. Conditional pushdown systems were developed for just such a conundrum, but existing methods are ill-suited for the dynamic nature of garbage collection. We show fully precise and approximate solutions to the feasible paths problem for pushdown garbage-collecting control-flow analysis. Experiments reveal synergistic interplay between garbage collection and pushdown techniques, and the fusion demonstrates “better-than-both-worlds” precision.
Three species of Hymenoptera comprise the guild of parasitoids utilizing alfalfa weevil, Hypera postica, larvae in Ohio. Where all three coexist, there has been a yearly increase in parasitization by Bathyplectes anurus and concomitant decreases in Bathyplectes curculionis and Tetrastichus incertus. We conclude that B. anurus dominance is due to its precise synchronization with peak host numbers, its high reproductive capacity, competitive superiority, and rapid search and handling. Domination of ephemeral hosts by such a parasitoid is in agreement with the general conclusions of Force, and Ehler and van den Bosch. B. curculionis and T. incertus compensate for imperfect synchrony with multivoltism and vagility (both spp.), aggregation and rapid search (B. curculionis), or random search and gregarious development (T. incertus).
Tetrastichus incertus, a parasite of the alfalfa weevil (Hypera postica) larva, occurs throughout the northeastern United States, including almost all of New York. Field studies in 1967 and 1968 indicated that the parasite and its host were not closely synchronized in New York; the parasite was uncommon in June when hosts were abundant while the opposite was true in July. In 1966 and 1967, the proportion of parasites entering diapause increased throughout the summer, from 1–31% in June to 67–100% in September. Therefore, most parasites produced in June, when hosts were abundant, emerged in July when hosts were scarce. Winter mortality among parasites in diapause was high (51–64%) in field cages. The survivors of the overwintering generation of T. incertus constituted a small fraction of the annual production of parasites.
In the laboratory the offspring of older T. incertus tended more to enter diapause than did the offspring of younger parasites. This indicated the incidence of diapause may be correlated with host availability; when hosts are uncommon, diapausing parasites are produced.
Field and laboratory data indicated a ratio of one T. incertus to eight alfalfa weevil larvae would be necessary to achieve 50% parasitism of the host population. Such a host:parasite ratio never occurs when the hosts are common.
In patients with smear-positive pulmonary tuberculosis who are hospitalized or reside in congregate settings, guidelines recommend airborne infection isolation until sputum smear results are negative. Studies have identified factors associated with delayed sputum smear and culture conversion in patients with tuberculosis. Because these studies did not use methods of survival analysis, estimates of time to sputum smear conversion that are based on initial patient characteristics are not available. The ability to predict time to sputum smear conversion could be useful for programmatic planning and patient counseling.
We performed a cohort study using survival analysis to identify factors associated with time to sputum smear and culture conversion. We defined the time to sputum smear conversion as the time elapsed from the start of treatment to the first date of sustained conversion.
Ninety-eight patients had sputum smear samples positive for acid-fast bacilli. Lower initial smear grade (on 1+ to 4+ scale) and absence of cavitation on chest radiograph were associated with earlier sputum smear conversion in bivariate analysis. In multiple regression analysis, initial smear grade (hazard ratio, 0.45; 95% confidence interval, 0.35-0.57) and drug resistance (hazard ratio, 2.30; 95% confidence interval, 1.08-4.89) remained statistically significant; a model comprising only initial smear grade performed almost as well. Predictors of sputum culture conversion were similar.
Initial smear grade was the strongest predictor of time to sputum smear and culture conversion in patients with pulmonary tuberculosis and may be a useful predictor for programmatic planning and patient counseling.
Any insect (or other) pest exists within an ecosystem, consisting of the surrounding biological and physical environment with which it interacts. The interactions between a pest population and its ecosystem are highly complex, and in many cases several pests with different biologies need to be simultaneously managed on a single crop. Ecological issues are exacerbated as the scale of management increases. On a typical farm in midwestern USA we might find fields producing maize (corn), soybeans, hay and perhaps small grains or canola, plus several species of vegetables in a family garden, several kinds of livestock and poultry, stored feed and seed, landscaping plantings, weeds, wildlife and the farmer and his/her household, any and all of which might harbor populations of one or more pests. The farm ecosystem occurs in a matrix of surrounding systems each with its own communities including pests. Ecological processes within surrounding habitats influence events within adjacent areas. In our efforts to maintain high yields and maximize profits, we often oversimplify and override ecosystem processes and unknowingly disrupt whatever naturally occurring pest population regulation there may be. Kogan (1995) and others have noted that even successful IPM programs may pay little heed to the complexity and unpredictability of ecological processes. Our pest management efforts therefore are often disruptive of ecosystem functions. In order to develop more ecologically based IPM systems we need greater understanding of ecological processes. The present chapter introduces some of these fundamental ecological processes as they impact pest populations.
Feelings of nausea (N) and actual vomiting (V) are universal experiences of human beings and probably also of many animals. Most of the time both N and V are acute experiences that pass quickly and are of little medical or health significance. However, severe and/or prolonged N and/or V can be very distressing and even life threatening; for example in children when V is associated with diarrhoea and dehydration, or people who die through choking on their vomit.
As Stern (2002) has recently highlighted, N, like pain, fatigue and itchiness, is a private, subjective experience but one which is highly dependent upon the interplay of profound physiological and psychological factors. Both V and N share much in common as far as causal factors are concerned but V, unlike N, is an observable and objectively verifiable event. This has implications for medical assessment and treatment so that N may be under-recognized and under-treated compared with V. This is particularly pertinent in chemotherapy for cancer (e.g. Sun et al., 2002) (see ‘Chemotherapy’).
N and V are associated with many aspects of illness and healthcare and frequently are of clinical significance (e.g. bulimia with induced vomiting; viral infections; side effects of treatments, such as chemotherapy (Osaba et al., 1997) and in pregnancy (Chou et al., 2003), where clear relationships have been found between depression and N and V.
Atopic eczema has been defined as ‘an inflammatory disease, characterized by an itchy, erythmatous, poorly demarcated skin eruption, which has a predilection for the skin creases’ (Williams, 1994, cited in Charman, 1999). Symptoms include intractable itching, skin damage and soreness. Where it lasts into adulthood it becomes a lifelong disease where the typical pattern is of a labile course resulting in some uncertainty and insecurity. Eczema or atopic dermatitis (AD) is a common childhood condition. It usually presents during the first year of life (Barnetson & Rogers, 2002) and in 60–70% of cases clears up during teenage years, although relapses may occur (Charman, 1999). The remaining sufferers are older children, adolescents and adults with a chronic skin condition. Symptoms can be mild or severe, and if severe can have both physical and psychological repercussions for the sufferer and the whole family.
Eczema is probably the most common of the atopy diseases to come to the attention of psychologists and psychiatrists for treatment and may co-exist with other atopy disorders in up to 48% of cases (Diepgen & Fartasch, 1992). Eczema affects 15–20% of children in the United Kingdom and 2–3% of adults (Charman, 1999), with a rising trend of incidence of twofold to threefold over the past three decades (Barnetson & Rogers, 2002). A large cross-sectional survey of 715 033 children and adolescents, in 56 countries, revealed a range of prevalence rates from less than 2% in Iran to over 17% in Nigeria.
Over recent decades ostracods have become established indicators of ecosystem health, biodiversity and environmental change. With applications ranging across the earth sciences (from modern pollution studies to sea-level change, basin evolution, plate tectonics, palaeoceanography) and related disciplines such as archaeology, ecology and genetics, their utility extends to almost every aquatic and semi-aquatic habitat, from the deep ocean to high mountain springs. Their temporal range is now known to cover the last 500 million years of earth history.
The study of fossil ostracod assemblages follows traditional palaeontological lines of investigation, including taphonomy, morphometries and diversity, but there are a number of methodological approaches, specific to the ostracods, that render them potentially one of the most versatile organisms in the fossil record. Ostracods have been employed on a range oftemporal and spatial scales to reconstruct past environments, from world-wide, geological-scale global events in the deep-sea through to smaller-scale studies of lakes and their archives of local environmental change over recent centuries.
Much information can be obtained from ostracod assemblages but it is particularly through recent advances in the chemical and physical study of single shells or carapaces that the utility of these organisms has been brought to the fore. In this paper the potential palaeoenvironmental information derived from an ostracod assemblage, a single species, or an individual shell is reviewed. The main applications for ostracods are outlined for marine and non-marine ecosystems. Finally, the role of the ostracods in detailing the recent history of the Aral Sea is outlined.
Ostracodes are ecologically diverse at the present day, inhabiting marine, nonmarine and (semi)terrestrial environments. Modern benthic faunas are dominated by Podocopa (marine and nonmarine Podocopida, marine Platycopida, and extremely rare marine Palaeocopida), while the Myodocopa (Myodocopida and Halocyprida) are diverse in the marine pelagic realm, as well as having many nektobenthic taxa. Their excellent fossil record facilitates reconstructions of their phylogenetic relationships and ecological adaptations throughout their Phanerozoic history. The earliest known ostracodes are of Ordovician age, when representatives of the extant orders Podocopida, Platycopida and Palaeocopida were already present, together with (possible) early Myodocopa and extinct orders such as the Leperditicopida. Cambrian bivalved arthropods such as bradoriids and phosphatocopids are no longer regarded as Ostracoda.
Ordovician ostracodes were predominantly marine meiobenthos, diversifying into depth-related assemblages dominated by palaeocopids. The beginnings of podocopan radiations in marginal marine environments (brackish and hypersaline waters) are seen in the Silurian, as is an ecological shift of nektobenthic myodocopans to form the first pelagic ostracode faunas. Of the diverse marine Paleozoic palaeocopids, only a single lineage, the puncioids, survived beyond the Permian and today live interstitially in high-energy shallow marine environments. Post-Paleozoic marine benthic ostracode faunas are dominated by cytheroidean podocopids which gave rise to several radiations in the Mesozoic and Cenozoic. The healdiid metacopines (podocopans), of Devonian origins, enjoyed a marine radiation in the Triassic and Early Jurassic and then became extinct. Marine platycopids were also significant components of Mesozoic marine faunas and are relatively diverse in warm, shallow carbonate environments today.
Suggestions that the first freshwater ostracodes were Devonian leperditicopids are controversial; undoubted nonmarine / freshwater radiations developed during the Early Carboniferous, including darwinuloidean and carbonitoidean podocopids and possibly some platycopids, together with cytheroidean podocopids (limnocytherids) in the Late Carboniferous. Of these only the darwinuloideans and limnocytherids survived the end-Permian extinctions and are still found in modern nonmarine waters; however, the dominant freshwater ostracodes today are the cypridoidean podocopids, whose radiation began in the Triassic and attained explosive proportions in the Late Jurassic - Early Cretaceous (although there are controversial suggestions of Paleozoic origins for this group). In addition to the limnocytherids there have been several other, separate invasions of nonmarine waters by cytheroidean podocopids, notably the cytherideids and the commensal entocytherids. Radiations in damp terrestrial environments have been initiated by both marine and nonmarine groups, but such invasions lack a recognized fossil record; (semi)terrestrial cypridoideans and darwinuloideans may represent Late Mesozoic radiations, while the Terrestricytheroidea, with marine affinities, may be much older, possibly Late Paleozoic in origin.
Intensive case management is commonly advocated for the care of the severely mentally ill, but evidence of its cost-effectiveness is lacking.
To investigate the cost-effectiveness of intensive compared with standard case management for patients with severe psychosis.
708 patients with psychosis and a history of repeated hospital admissions were randomly allocated to standard (case-loads 30–35) or intensive (case-loads 10–15) case management. Clinical and resource use data were assessed over two years.
No statistically significant difference was found between intensive and standard case management in the total two-year costs of care per patient (means £24 550 and £22 700, respectively, difference £1850, 95% Cl – £1600 to £5300). There was no evidence of differential effects in African–Caribbean patients or in the most disabled. Psychiatric in-patient hospital stay accounted for 47% of the total costs, but neither such hospitalisation nor other clinical outcomes differed between the randomised groups.
Reduced case-loads have no clear beneficial effect on costs, clinical outcome or cost-effectiveness. The policy of advocating intensive case management for patients with severe psychosis is not supported by these results.
a skin condition with a multifaceted aetiology that includes both psychological and physiological components.
A number of studies have indicated that cognitive-behavioural techniques (e.g. relaxation) are effective in
the treatment of atopic eczema. However, it remains unclear from the literature whether different relaxation
techniques have comparable treatment effects. The current study compared the efficacy of a single relaxation
session with an imagery component with that of a comparable relaxation session without the imagery component.
Eczema patients (n=9) who participated in relaxation with imagery reported significantly greater
reductions in state anxiety and subjective ratings of itchiness and significantly greater increases in mental
relaxation levels than eczema patients (n=9) who participated in relaxation without the imagery
component. No group differences were found on changes in state anger. These results suggest that relaxation
with an imagery component may be more effective than relaxation without an imagery component in lowering state
anxiety levels and itchy sensations of atopic eczema patients.
Visual Analogue Scales (VAS) provide a simple technique for measuring subjective experience. They have been established as valid and reliable in a range of clinical and research applications, although there is also evidence of increased error and decreased sensitivity when used some subject groups. Decisions concerned with the choice of scoring interval, experimental design, and statistical analysis for VAS have in some instances been based on convention, assumption and convenience, highlighting the need for more comprehensive assessment of individual scales if this versatile and sensitive measurement technique is to be used to full advantage.
Milk samples from three groups of cows were taken at frequent intervals throughout lactation following autumn-, winter- or spring-calving. The ethanol (EtOH) stability/pH profile was determined for each sample and its characteristic parameters calculated. The lactational trends in these parameters were examined. Asymptotic maximum EtOH stability (Smax) was low in early lactation but rose rapidly to a value which showed no further lactational trends. Asymptotic minimum stability (Smin) for samples from autumn- and winter-calving cows showed a decrease which could be associated with the transition to summer grazing but no obvious lactational effects. The slope parameter increased slowly during lactation. The profile pK value decreased in early lactation, but thereafter increased throughout lactation giving the most obvious effect observed in direct measurement, namely an alkaline shift in the profile as lactation progressed. The EtOH stability calculated at a fixed pH of 6·6 passed through a maximum, characteristic for each cow, in the first weeks of lactation but declined steadily thereafter. This behaviour mirrors the lactational behaviour of the soluble salt balance ratio calculated from the original data of White & Davies (1958).