Chosen-Plaintext Cryptanalysis of a Clipped-Neural-Network-Based Chaotic Cipher

In ISNN'04, a novel symmetric cipher was proposed, by combining a chaotic signal and a clipped neural network (CNN) for encryption. The present paper analyzes the security of this chaotic cipher against chosen-plaintext attacks, and points out that this cipher can be broken by a chosen-plaintext attack. Experimental analyses are given to support the feasibility of the proposed attack.Comment: LNCS style, 7 pages, 1 figure (6 sub-figures

Andrographolide Inhibits PI3K/AKT-Dependent NOX2 and iNOS Expression Protecting Mice against Hypoxia/Ischemia-Induced Oxidative Brain Injury

This study aimed to explore the mechanisms by which andrographolide protects against hypoxia-induced oxidative/nitrosative brain injury provoked by cerebral ischemic/reperfusion (CI/R) injury in mice. Hypoxia in vitro was modeled using oxygen-glucose deprivation (OGD) followed by reoxygenation of BV-2 microglial cells. Our results showed that treatment of mice that have undergone CI/R injury with andrographolide (10-100 mu g/kg, i.v.) at 1 h after hypoxia ameliorated CI/R-induced oxidative/nitrosative stress, brain infarction, and neurological deficits in the mice, and enhanced their survival rate. CI/R induced a remarkable production in the mouse brains of reactive oxygen species (ROS) and a significant increase in protein nitrosylation; this primarily resulted from enhanced expression of NADPH oxidase 2 (NOX2), inducible nitric oxide synthase (iNOS), and the infiltration of CD11b cells due to activation of nuclear factor-kappa B (NF-kappa B) and hypoxia-inducible factor 1-alpha (HIF-1 alpha). All these changes were significantly diminished by andrographolide. In BV-2 cells, OGD induced ROS and nitric oxide production by upregulating NOX2 and iNOS via the phosphatidylinositol-3-kinase (PI3K)/AKT-dependent NF-kappa B and HIF-1 alpha pathways, and these changes were suppressed by andrographolide and LY294002. Our results indicate that andrographolide reduces NOX2 and iNOS expression possibly by impairing PI3K/AKT-dependent NF-kappa B and HIF-1 alpha activation. This compromises microglial activation, which then, in turn, mediates andrographolide's protective effect in the CI/R mice

GONADOTROPHIN RESPONSES TO GnRH PULSES IN HYPOGONADOTROPHIC HYPOGONADISM: LH RESPONSIVENESS IS MAINTAINED IN THE PRESENCE OF LUTEAL PHASE CONCENTRATIONS OF OESTROGEN AND PROGESTERONE

LH pulse secretion changes during the menstrual cycle from a rapid regular pattern in the follicular phase to a slower and irregular pattern in the luteal phase. To determine whether the irregular LH pulse pattern in the luteal phase reflects altered GnRH secretion or altered pituitary responsiveness to GnRH, we gave low dose GnRH pulses (25 ng/kg i.v.) every 2 h or every hour for 10 or 12 d to three women with isolated GnRH deficiency. After 4 d of GnRH alone, oestradiol (E 2 ) was given and after 6 d progesterone (P) was added to mimic the hormonal milieu of the luteal phase. LH and FSH were measured every 4 h throughout and also every 20 min for 6 or 12 h, before and after GnRH alone (day 0 and day 4), after E 2 (day 6), and after E 2 + P (day 10 and day 12). Both GnRH pulse frequencies resulted in a rapid increase in plasma FSH to peaks on day 4 (every 2 h) and day 2 and 3 (every hour). FSH concentrations then declined as plasma E 2 rose to 50–80 pg/ml reflecting the selective inhibitory effect of E 2 on FSH release. Plasma LH was also increased after the hourly GnRH injections and this regimen was associated with a more rapid rise in E 2 reflecting follicular maturation. In contrast to the differences in mean hormone concentrations, administration of GnRH at both frequencies resulted in sustained one-on-one responsiveness of LH that was maintained in the presence of both oestrogen and progesterone at mid-luteal phase concentrations. We conclude that the slow frequency of LH pulses observed during the luteal phase reflects decreased GnRH pulse frequency rather than impaired pituitary responsiveness to GnRH.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74947/1/j.1365-2265.1987.tb00786.x.pd

Polyphasic taxonomy of Aspergillus section Candidi based on molecular, morphological and physiological data

Aspergillus section Candidi historically included a single white-spored species, A. candidus. Later studies clarified that other species may also belong to this section. In this study, we examined isolates of species tentatively assigned to section Candidi using a polyphasic approach. The characters examined include sequence analysis of partial β-tubulin, calmodulin and ITS sequences of the isolates, morphological and physiological tests, and examination of the extrolite profiles. Our data indicate that the revised section Candidi includes 4 species: A. candidus, A. campestris, A. taichungensis and A. tritici. This is strongly supported by all the morphological characteristics that are characteristic of section Candidi: slow growing colonies with globose conidial heads having white to yellowish conidia, conidiophores smooth, small conidiophores common, metulae present and covering the entire vesicle, some large Aspergillus heads with large metulae, presence of diminutive heads in all species, conidia smooth or nearly so with a subglobose to ovoid shape, and the presence of sclerotia in three species (A. candidus, A. taichungensis and A. tritici). Aspergillus tritici has been suggested to be the synonym of A. candidus previously, however, sequence data indicate that this is a valid species and includes isolates came from soil, wheat grain, flour and drums from India, Ghana, Sweden, The Netherlands and Hungary, making it a relatively widespread species. All species produce terphenyllins and candidusins and three species (A. candidus, A. campestris and A. tritici) produce chlorflavonins. Xanthoascins have only been found in A. candidus. Each of the species in section Candidi produce several other species specific extrolites, and none of these have been found in any other Aspergillus species. A. candidus has often been listed as a human pathogenic species, but this is unlikely as this species cannot grow at 37 °C. The pathogenic species may be A. tritici or white mutants of Aspergillus flavus

Effects of follicular phase exercise on luteinizing hormone pulse characteristics in sedentary eumenorrhoeic women

OBJECTIVE Current studies reveal little regarding the Inception of exercise-induced LH changes during physical training. This study aimed to assess the susceptibility of the hypothalamic–pituitary axis to the acute physical stress of exercise in untrained, physically inactive women. The acute effects of submaximal endurance exercise upon the pulsatile LH secretion in the follicular phase were compared with those accompanying leisurely strolling for a similar time period. SUBJECTS All subjects were eumenorrhoelc, as determined by biphasic temperature patterns, detection of the urinary LH surge, and mid-luteal serum progesterone levels. Subjects were not physically active and had little history of strenuous exercise ( V o 2 max = 38·0 ± 1·8) (mean ± SEM) ml/kg/min). DESIGN All women completed a 13·5-hour pulsatility test which included three consecutive 20-minute runs on a treadmill at 50, 60 and 70% of the subjects’maximum oxygen uptake ( n = 16). Six of these same subjects completed a separate test on another occasion in which one hour of leisurely strolling was substituted for exercise. Blood was sampled every 10 minutes via an indwelling cannula for 4·5 hours before and 8 hours after one hour of exercise and or strolling. MEASUREMENTS A pulse algorithm (Pulsar) was used to quantify LH pulse characteristics. RESULTS Exercise produced no significant effects upon LH pulse frequency or mean serum LH concentration. However, exercise of moderate intensity caused a significant increase in LH pulse amplitude ( P < 0·05). Strolling produced no significant changes in LH secretion. CONCLUSION Acute exercise of moderate intensity in the follicular phase of untrained women is an insufficient stimulus to inhibit the GnRH pulse generator in the post-exercise period, yet may produce a slight stimulatory effect on the amount of LH released per pulsePeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73507/1/j.1365-2265.1994.tb02794.x.pd

The incidence of fatal breast cancer measures the increased effectiveness of therapy in women participating in mammography screening

Background: Women and their health care providers need a reliable answer to this important question: If a woman chooses to participate in regular mammography screening, then how much will this choice improve her chances of avoiding a death from breast cancer compared with women who choose not to participate?Methods: To answer this question, we used comprehensive registries for population, screening history, breast cancer incidence, and disease‐specific death data in a defined population in Dalarna County, Sweden. The annual incidence of breast cancer was calculated along with the annual incidence of breast cancers that were fatal within 10 and within 11 to 20 years of diagnosis among women aged 40 to 69 years who either did or did not participate in mammography screening during a 39‐year period (1977‐2015). For an additional comparison, corresponding data are presented from 19 years of the prescreening period (1958‐1976). All patients received stage‐specific therapy according to the latest national guidelines, irrespective of the mode of detection.Results: The benefit for women who chose to participate in an organized breast cancer screening program was a 60% lower risk of dying from breast cancer within 10 years after diagnosis (relative risk, 0.40; 95% confidence interval, 0.34‐0.48) and a 47% lower risk of dying from breast cancer within 20 years after diagnosis (relative risk, 0.53; 95% confidence interval, 0.44‐0.63) compared with the corresponding risks for nonparticipants.Conclusions: Although all patients with breast cancer stand to benefit from advances in breast cancer therapy, the current results demonstrate that women who have participated in mammography screening obtain a significantly greater benefit from the therapy available at the time of diagnosis than do those who have not participated.</p

A Pre-Landing Assessment of Regolith Properties at the InSight Landing Site

This article discusses relevant physical properties of the regolith at the Mars InSight landing site as understood prior to landing of the spacecraft. InSight will land in the northern lowland plains of Mars, close to the equator, where the regolith is estimated to be ≥3--5 m thick. These investigations of physical properties have relied on data collected from Mars orbital measurements, previously collected lander and rover data, results of studies of data and samples from Apollo lunar missions, laboratory measurements on regolith simulants, and theoretical studies. The investigations include changes in properties with depth and temperature. Mechanical properties investigated include density, grain-size distribution, cohesion, and angle of internal friction. Thermophysical properties include thermal inertia, surface emissivity and albedo, thermal conductivity and diffusivity, and specific heat. Regolith elastic properties not only include parameters that control seismic wave velocities in the immediate vicinity of the Insight lander but also coupling of the lander and other potential noise sources to the InSight broadband seismometer. The related properties include Poisson’s ratio, P- and S-wave velocities, Young’s modulus, and seismic attenuation. Finally, mass diffusivity was investigated to estimate gas movements in the regolith driven by atmospheric pressure changes. Physical properties presented here are all to some degree speculative. However, they form a basis for interpretation of the early data to be returned from the InSight mission.Additional co-authors: Nick Teanby and Sharon Keda