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Investigating the effect of photodynamic therapy on nerves using tissue engineered culture models
Introduction: Photodynamic therapy (PDT) shows potential as an effective treatment for prostate cancer. Clinical observations indicate that this approach causes fewer nerve damage related side-effects than conventional treatments. The aim here is to investigate the effect of PDT on nerve tissue using engineered 3-dimensional cell culture models. Initial experiments focussed on establishing photosensitiser localisation in neurones and Schwann cells, then developing a model for simulating nerve PDT in culture
The road to hormonal male contraception: end in sight?
The concept of a hormonal approach that sufficiently and reversibly suppresses spermatogenesis to the level required for effective contraception has been developed and tested over several decades. The reality of achieving this has been confirmed using both testosterone alone and combination methods using a progestogen with a physiological dose of testosterone, necessary to replace the lack of endogenous testosterone production by the suppressed testes. A range of both long-acting and self-administered combination methods are effective, including injection, implant and gel methods of administration, with up to 95% of men achieving sufficient spermatogenic suppression. New steroids are also being trialled. Surveys show the widespread willingness of men and their female partners to use novel male methods, suggesting the potential of this approach to contribute to global family planning and sustainable development goals. This approach to contraception can clearly be effective, and needs to move from relatively small scale testing to large scale pre-marketing trials: only then can information about long-term safety and real-world acceptability be obtained
The lipid content and fatty acid composition of hatched second stage juveniles of Globodera rostochiensis and G. pallida
Les juvéniles de deuxième stade (J2) de #Globodera rostochiensis en contiennent en moyenne 27,2%. Les lipides des J2 de #G. rostochiensis J2 sont composés de 73,0% de lipides neutres, 13,2% d'acides gras libres et 13,8% de phospholipides. 77,4% des acides gras totaux de #G. rostochiensis sont insaturés. Les deux espèces présentent un profil d'acides gras similaire. Vingt acides gras ont été identifiés, allant de C14 à C22 ; les principales classes de lipides sont surtout composées d'acides gras en C20 (50-60%) et C18 (30-35%). Les trois acides gras les plus abondants caractérisés chez les deux espèces sont C20:4, C20:1 et C18:1, représentant à eux seuls plus de 60% du total. Les J2 de #G. rostochiensis$ récoltés toutes les 24 heures au cours des première et seconde semaines après l'exposition aux PRD, présentent la même composition en acides gras que les J2 récoltés toutes les 96 heures pendant les troisième et quatrième semaines. (Résumé d'auteur
A simple two-module problem to exemplify building-block assembly under crossover
Theoretically and empirically it is clear that a genetic algorithm with crossover will outperform a genetic algorithm without crossover in some fitness landscapes, and vice versa in other landscapes. Despite an extensive literature on the subject, and recent proofs of a principled distinction in the abilities of crossover and non-crossover algorithms for a particular theoretical landscape, building general intuitions about when and why crossover performs well when it does is a different matter. In particular, the proposal that crossover might enable the assembly of good building-blocks has been difficult to verify despite many attempts at idealized building-block landscapes. Here we show the first example of a two-module problem that shows a principled advantage for cross-over. This allows us to understand building-block assembly under crossover quite straightforwardly and build intuition about more general landscape classes favoring crossover or disfavoring it
DNA sequences required for regulated expression of β-globin genes in murine erythroleukaemia cells.
We introduced into MEL cells rabbit beta-globin gene deletion mutants and two sets of hybrid genes constructed from the inducible human beta-globin gene and noninducible human gamma-globin gene or the murine H-2Kbm1 class I MHC gene. S1 nuclease analysis of gene transcripts before and after MEL differentiation showed that induction of the rabbit beta-globin gene did not require more than 58 bp of DNA 5' to the transcription initiation site. Hybrid genes were constructed with human beta-globin DNA sequences from either 5' or 3' of the translation initiation site linked to the complementary parts of the gamma or H2Kbm1 genes. Both types of constructs were inducible during MEL differentiation. The relative rates of transcription of the 5' gamma-3' beta and 5'H2-3' beta hybrid genes show that induction of the hybrid gene transcripts results at least in part from transcriptional activation of the genes. We suggest that DNA sequences that regulate beta-globin gene transcription during MEL differentiation are located both 5' and 3' to the translation initiation site
Air Temperature and Vapor Pressure Changes Caused by Sprinkler Irrigation
The downwind effect of evaporation from sprinkler
spray was studied in the field to determine if air temperature
and vapor pressure were changed enough to
influence plant growth and water use. Wet-bulb and
dry-bulb temperature profiles were measured upwind
and at three distances downwind from a sprinkler lateral
before and during sprinkling. Wind-speed and direction
were also measured. Air temperature generally was reduced
less than 1 C, and vapor pressure in the air was
increased less than 0.8 mb. This amount of change in
the air temperature and humidity is not likely to be sufficient
to cause any significant change in plant growth or
evaporative loss of water
The empirical relevance of the competitive storage model
"The empirical relevance of models of competitive storage arbitrage in explaining commodity price behavior has been seriously challenged in a series of pathbreaking papers by Deaton and Laroque (1992, 1995, 1996). Here we address their major criticism, that the model is in general unable to explain the degree of serial correlation observed in prices of twelve major commodities. First, we present a simple numerical version of their model which, contrary to Deaton and Laroque (1992), can generate the high levels of serial correlation observed in commodity prices, if it is parameterized to generate realistic levels of price variation. Then, after estimating the Deaton and Laroque (1995, 1996) model using their data set, model specification and econometric approach, we show that use of a much finer grid to approximate the equilibrium price function yields quite different estimates for most commodities. Results are obtained for coffee, copper, jute, maize, palm oil, sugar and tin that support the specifications of the storage model with positive constant marginal storage cost and no deterioration as in Gustafson (1958a). Consumption demand has low response to price and, except for sugar, there are infrequent stockouts. Observed magnitudes of serial correlation of price match those implied by the estimated model." [author's abstract
Onion Seed Yield and Quality as Affected by Irrigation Management
The effects of soil moisture, sprinkler irrigation, and
misting (5 min at 30-min intervals) on hybrid onion-seed
(Allium cepa L.) production were evaluated at Kimberly,
Idaho. Sprinkling and misting treatments were included
to determine if sprinkler irrigation could be used for
onion-seed production, and if evaporative cooling (misting)
would alleviate the scalding of umbels at excessively
high temperatures. Results showed that reasonable onionseed
yields could be obtained with sprinkler irrigation in
spite of anticipated adverse effects on pollination. In
areas with high daytime temperatures, misting could be
used to cool the umbels, as much as 15 C for about 20
min, although it does not seem necessary for the low 32
to 35 C daytime temperatures at Kimbqly. The highest
anion-seed yields were obtained with the furrow-irrigation
treatment where water was applied when tensiometers at
20-cm depth read about 0.5 bar soil moisture tension (furrow
adequate). The addition of misting to furrow irrigation
decreased seed yields 19%. Furrow irrigating at
0.4 bar decreased yields 26% below those obtained with irrigation
at 0.5 bar. While overirrigation adversely affected
yield, irrigation treatment had only a slight effect on
seed weight and vigor
Faster Approximate String Matching for Short Patterns
We study the classical approximate string matching problem, that is, given
strings and and an error threshold , find all ending positions of
substrings of whose edit distance to is at most . Let and
have lengths and , respectively. On a standard unit-cost word RAM with
word size we present an algorithm using time When is
short, namely, or this
improves the previously best known time bounds for the problem. The result is
achieved using a novel implementation of the Landau-Vishkin algorithm based on
tabulation and word-level parallelism.Comment: To appear in Theory of Computing System
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