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THE MATERIAL CULTURE OF ASTRONOMY IN DAILY LIFE: SUNDIALS, SCIENCE, AND SOCIAL CHANGE
No full textSundials are among the most ancient of astronomical instruments. The earliest surviving examples date from 1500 B.C. By tracing the length and angles of shadows and by employing mathematical projections of the celestial sphere, early dials marked the passage of time, the recurring seasons, and the apparent motion of the sun in the sky. They refl ected time consciousness. Sundials have also been time discipliners. Since Hellenistic times, they have been used to coordinate activities such as meals, prayers, and business. With the rise of commercial society in the late Middle Ages, a new sense of time pressure led to increased production and further development of sundials. Personal timepieces kept busy people on schedule. One goal of this paper is to show how the material culture refl ected changes in people's experience of time consciousness, time discipline, and time pressure. A second goal is to explore the place of sundials in consumer culture. People acquired sundials, like other consumer goods, for many reasons: because they needed or desired them; or because the goods had symbolic value or projected a particular image of their owners (cf. Historiographically, this is a new way of looking at old sundials. Often curators and sundial enthusiasts focus their attention on the mathematics of the different types of dials, the panoply of shapes and designs, or the craftsmanship of particular instrument makers. These are worthwhile projects and require considerable connoisseurship. I aim to go beyond these studies in order to explore not only the supply side, but also the demand side of the sundial trade. Mathematicians designed and instrument makers produced sundials to serve and please their customers. The three groups -mathematicians, makers, and consumers -were not in mutual isolation. Material culture was the link between theory, production, and consumption, and it sheds light on all. I take as my foundation a careful study of over two thousand historic sundials preserved in museums worldwide. Although literary evidence is useful, it is only by the close inspection and comparison of many dials from different places and periods that one can build a picture of astronomy and mathematics in daily life. Two great sundial collections are at the Adler Planetarium and Astronomy Museum in Chicago and the Harvard Collection of Historical Scientifi c Instruments. This paper will be illustrated by instruments in both museums. , xxxii (2001) JH
A Systematic Review
No full textAbstract To systematically review the literature on the relationship between early childhood low income/socioeconomic status (SES) and physical health in later childhood/adolescence, to identify gaps in the literature and to suggest new avenues for research. A systematic search of electronic databases from their start date to November 2011 was conducted to identify prospective longitudinal studies in industrialized countries with a measure of low income/SES in the first 5 years of life and physical health outcomes in later childhood or adolescence. STROBE criteria were used to assess study quality. Risk estimates were expressed as odds ratios with 95 % confidence intervals where possible. Heterogeneity of studies precluded meta-analysis. Nine studies fulfilled the inclusion criteria. Significant associations of early childhood low income/SES with activity-limiting illness, parent-reported poor health status, acute and recurrent infections, increasing BMI percentile and hospitalization were reported. Results for parent-reported asthma were less consistent: there was a significant association with low income/ SES in early childhood in 2 studies but null findings in 3 others. This systematic review of the association of early childhood low income/SES with physical health status in later childhood and adolescence shows that, in contrast to the extensive literature on the impact of poor childhood social circumstances on adult health, the evidence base is limited. The literature points to some associations of early low income/SES with later poor health status, but many key research questions remain unanswered. Implications for further research are considered
An electromyographical study to investigate the effects of patellar taping on the vastus medialis=vastus lateralis ratio in asymptomatic participants
No full textIt is commonly theorised that patellofemoral pain syndrome (PFPS) is caused by maltracking due to vastus medialis (VM) weakness relative to the vastus lateralis (VL). Despite this being a controversial theory, patellar taping is a commonly used technique that purports to correct this muscle imbalance by increasing the VM=VL ratio. The effects of different forms of taping on vasti muscle activity are still not known. The objective of this study was to investigate the effects of three different types of patellar taping on the VM=VL ratio in asymptomatic university students. Each participant performed a set of four singleÀlegged squats under four separate taping conditions: A) medial, B) lateral, C) neutral, and D) no-tape. The condition sequence was randomised. The main outcome measure was the normalised VM=VL ratio, assessed by using surface electromyography. Secondary outcome measures were the normalised EMG activity of the VM and the VL. A convenience sample of 24 (17 females) students (22AE10 years, MAESD) completed this study. The lateral taping condition produced small but significantly greater VM=VL ratios than the medial (p ¼ 0.007) and neutral (p ¼ 0.007) but not the no-tape (p ¼ 0.123) condition. There were no significant differences between the medial, neutral, and no-tape conditions. These results question whether patellar taping can impart a clinically significant effect on the VM=VL ratio. The results of this study cannot be directly extrapolated to a patient population, and further research in the PFPS population is required before clinical recommendations can be made
Transfection of Platyhelminthes
No full textFlatworms are one of the most diverse groups within Lophotrochozoa with more than 20,000 known species, distributed worldwide in different ecosystems, from the free-living organisms in the seas and lakes to highly specialized parasites living in a variety of hosts, including humans. Several infections caused by flatworms are considered major neglected diseases affecting countries in the Americas, Asia, and Africa. For several decades, a particular interest on free-living flatworms was due to their ability to regenerate considerable portions of the body, implying the presence of germ cells that could be important for medicine. The relevance of reverse genetics for this group is clear; understanding the phenotypic characteristics of specific genes will shed light on developmental traits of free-living and parasite worms. The genetic manipulation of flatworms will allow learning more about the mechanisms for tissue regeneration, designing new and more effective anthelmintic drugs, and explaining the host-parasite molecular crosstalk so far partially inaccessible for experimentation. In this review, availability of transfection techniques is analyzed across flatworms, from the initial transient achievements to the stable manipulations now developed for free-living and parasite species. Platyhelminth Transfection Studies The phylum Platyhelminthes or flatworms represent one of the most diverse groups within Lophotrochozoa with about 20,000 species distributed worldwide including free-living and parasitic organism classified into 17 major groups Developing techniques to manipulate flatworms is a growing topic in contemporary research as judged by the number of reports published during the last decade Maintenance of parasite species under laboratory conditions has been challenging and genetic manipulation is still difficult Digenean Trematodes Trematode infections reach high prevalence in developing countries An application of transient transfection methodologies is the silencing of specific genes through RNAi, involving studies on worm viability, development, tegument physiology, egg development, signaling pathways, and drug discovery. Efficacy of RNAi can be influenced by the method of delivery: the more often used in schistosomes are soaking and electroporation [8] and the most frequently used RNAi in schistosomes is dsRNA (long double stranded), followed by siRNA (small interfering) Cestodes Among cestodes the most important infections in public health are cysticercosis and hydatosis or echinococcosis, with high global prevalence in endemic countrie
H (2004) Impact of differential parasitoid attack on number of chambers in multilocular galls of two closely related gall midges (Diptera: Cecidomyiidae
No full textABSTRACT We examined the influence of differential selection by natural enemies on the number of chambers in the galls of two closely related gall midges: Asteralobia sasakii and A. soyogo. To evaluate the selection pressure imposed by parasitoid wasps, we investigated the number of larval chambers (as represented by the number of larvae) and the rate of parasitism in each gall. Galls with smaller numbers of either species of cecidomyiid larvae were attacked more frequently by ectoparasitoids. In A. sasakii galls, the overall rate of attack by ectoparasitoids was higher than in A. soyogo galls, especially in galls with many larvae. Midge larvae of both species that hatched from larger egg clutches were attacked more frequently by endoparasitoids. In A. sasakii, the overall rate of attack by endoparasitoids was lower than in A. soyogo, especially in large clusters of larvae. Consequently, the final survival rate of A. sasakii peaked at higher larval numbers (14.5 per gall in 2000-01 and 10.1 per gall in 2001-02) than for A. soyogo (5.5 per gall in 2000-01 and 6.4 per gall in 2001-02). The mean number of larvae per gall was also higher in A. sasakii than in A. soyogo. Differences in the selection pressures exerted by natural enemies led to differences in the numbers of chambers in galls of the two different midge species and, in turn, different oviposition behaviours of midge females, reflecting variations in counter-strategies against parasitoids
The Date Palm Tree Rhizosphere Is a Niche for Plant Growth Promoting Bacteria in the Oasis Ecosystem
No full textIn arid ecosystems environmental factors such as geoclimatic conditions and agricultural practices are of major importance in shaping the diversity and functionality of plant-associated bacterial communities. Assessing the influence of such factors is a key to understand (i) the driving forces determining the shape of root-associated bacterial communities and (ii) the plant growth promoting (PGP) services they provide. Desert oasis environment was chosen as model ecosystem where agriculture is possible by the microclimate determined by the date palm cultivation. The bacterial communities in the soil fractions associated with the root system of date palms cultivated in seven oases in Tunisia were assessed by culture-independent and dependent approaches. According to 16S rRNA gene PCR-DGGE fingerprinting, the shapes of the date palm rhizosphere bacterial communities correlate with geoclimatic features along a north-south aridity transect. Despite the fact that the date palm root bacterial community structure was strongly influenced by macroecological factors, the potential rhizosphere services reflected in the PGP traits of isolates screened in vitro were conserved among the different oases. Such services were exerted by the 83% of the screened isolates. The comparable numbers and types of PGP traits indicate their importance in maintaining the plant functional homeostasis despite the different environmental selection pressures
Sustainability in Ecovillages -A Reconceptualization
No full textAbstract: This paper identifies and explores factors affecting sustainability and their interrelationships within the context of ecovillages. Through critical analysis of the theoretical concepts of sustainability and ecovillages as intentional communities, as well as their practical exploration through a multiple case study, a contextualised reconceptualization of sustainability is developed. The conceptual framework proposed in this paper depicts sustainability as a dynamic, context-dependent concept consisting of a variety of interdependent factors. The ecovillages looked at are held together by shared principles, which act as unifying themes. They translate the community characteristics (lifestyle, commitment, understanding) into community activities. These activities can be organised into different dimensions (environmental friendliness, economic alternatives, social network, organisation), all including the element of self-sufficiency to a greater or lesser extent. Sustainability has different levels (personal, community, global); ecovillages are connected to society and network with other communities, creating a link between the internal and external factors. Regular review processes address the dynamics of the factors; this self-reflexivity helps to keep the communities dynamic, and through the interrelationships of the factors can lead to enhanced sustainability. With a holistic approach to a reconceptualisation in a practical context, the conceptual model proposed in this paper facilitates a deeper understanding of the concept. Drawing on findings from a multiple case study conducted in Scotland and Germany, through in-depth interviews with inhabitants of ecovillages involved in the organisation of their communities, it offers a guideline for understanding sustainability in ecovillages and can serve as inspiration to rethink conceptualisations of sustainability to date
The Earned Income Tax Credit, welfare reform, and the employment of low-skilled single mothers
No full textRetrospective study of patients using Functional Electrical Stimulation for drop foot correction and increased hip stability
No full textAbstract This is an audit of patients attending the Salisbury Functional Electrical Stimulation Clinic for surface stimulation of common peroneal nerve and gluteal muscles. Results show this combination of stimulation is possible for patients with neurological deficit due to CVA and MS to set up and manage as part of their daily routine. From objective data significant improvements in speed and effort were found with stimulation. Significant improvements were found in non stimulated walking over six months of use in CVA group, which could indicate a training effect. For patients capable of managing the more complex equipment, stimulation of common peroneal nerve and gluteal muscles is an acceptable treatment to improve gait pattern and hip stability in stance, reduce effort and increase speed and distance patients can walk
Advantages of L-3-[ 18 F] fluoro-alpha-methyl tyrosine over 2-[ 18 F]-fluoro-2-deoxyglucose in detecting liver metastasis during positron emission tomography scan
No full textAbstract Purpose: We aimed to assess the usefulness of positron emission tomography (PET) using the amino acid tracer L-3-[18F] fluoro-alpha-methyl tyrosine (FAMT) in detecting metastatic liver lesions compared with 2-[18F]-fluoro-2-deoxyglucose (FDG). Methods: We included 24 patients with liver metastases who underwent both FDG-PET/computed tomography (CT) and FAMT-PET/CT. Maximum standardized uptake value (SUVmax) and tumor-to-liver parenchymal (T/L) ratio were analyzed to evaluate the correlation between FDG and FAMT uptakes in metastatic liver lesions; adenocarcinoma (AC, n = 21), squamous cell carcinoma (SCC, n = 23), neuroendocrine tumor (NET, n = 9), and carcinoid tumor (CAR, n = 6). Results: We detected 59 lesions on performing either FDG-PET or FAMT-PET. NETs had significantly lower T/L ratios for FAMT (median, 1.00; range, 0.86-1.34) compared with those for FDG (median 2.86; range 1.70-6.13, p < 0.01). CAR tumors tended to reveal lower T/L ratios for FDG (median 1.10; range 0.78-1.92) than those for FAMT (median 1.80; range 0.80-2.34). Comparison of T/L ratios of SCC and AC revealed that FAMT in the metastatic liver lesions of SCC was higher than those of AC (p < 0.05). Conclusion: FAMT-PET could detect metastatic liver lesions from various cancers, except NET