Influence of milk source on transplantability of histocompatible mammary tumours in mice.

It is confirmed that C3H mammary tumours are much more easily transplantable in histocompatible recipients when these have been reared on C3H milk, than when they have been reared on milk from the inbred Swiss/B strain. By contrast, A.CA mammary tumours transplanted in histocompatible hosts reared on A.CA or Swiss/B milk, grow almost equally well in both sorts of recipient. Thus, rearing on Swiss/B milk has different effects on the transplantability of mammary tumours of C3H and A.CA. On the other hand, recipients which were reared on C3H or A.CA milks accept grafts of C3H mammary tumours about equally, suggesting that milks from A.CA and C3H have the same effect on the transplantability of C3H mammary tumours. The different action of Swiss/B milk on tumours of C3H and A.CA seems best attributed to differences between C3H and A.CA tumours or between mouse strain genotypes. By contrast, the transplantability of C3H mammary tumours is significantly changed when the recipients were reared on milk from the RIII strain instead of C3H. These facts suggest that the milk from RIII has an action which differs from that of both C3H and A.CA in this respect. The data are discussed on the basis of a differential tollerance-inducing action of mammary tumour viruses (MTVs) which infect C3H, A.CA and RIII, and have an important role in tumour induction

Existence of a rotating wave pattern in a disk for a wave front interaction model

[[abstract]]We study the rotating wave patterns in an excitable medium in a disk. This wave pattern is rotating along the given disk boundary with a constant angular speed. To study this pattern we use the wave front interaction model proposed by Zykov in 2007. This model is derived from the FitzHugh-Nagumo equation and it can be described by two systems of ordinary differential equations for wave front and wave back respectively. Using a delicate shooting argument with the help of the comparison principle, we derive the existence and uniqueness of rotating wave patterns for any admissible angular speed with convex front in a given disk.[[incitationindex]]SCI[[booktype]]紙本[[booktype]]電子

Toward a cross-border early-warning system for central Asia

Rapidly expanding urban areas in Central Asia are increasingly vulnerable to seismic risk; but at present, no earthquake early warning (EEW) systems exist in the region despite their successful implementation in other earthquake-prone areas. Such systems aim to provide short (seconds to tens of seconds) warnings of impending disaster, enabling the first risk mitigation and damage control steps to be taken. This study presents the feasibility of a large scale cross-border regional system for Central Asian countries. Genetic algorithms are used to design efficient EEW networks, computing optimal station locations and trigger thresholds in recorded ground acceleration. Installation of such systems within 3 years aims to both reducing the endemic lack of strong motion data in Central Asia that is limiting the possibility of improving seismic hazard assessment, and at providing the first regional earthquake early warning system in the are

Designing efficient earthquake early warning systems: Case study of Almaty, Kazakhstan

Rapidly expanding urban areas in Central Asia are increasingly vulnerable to seismic risk; but at present, no earthquake early warning (EEW) systems exist in the region despite their successful implementation in other earthquake-prone areas. Such systems aim to provide short (seconds to tens of seconds) warnings of impending disaster, enabling the first risk mitigation and damage control steps to be taken. This study presents the feasibility of such a system for Almaty, Kazakhstan. Genetic algorithms are used to design efficient EEW networks, computing optimal station locations and trigger thresholds in recorded ground acceleration. Factors like the possibility of station failure, elevation and access difficulty to a potential site, and the potential usefulness of existing stations in the region are considered. We present a large set of possible efficient networks, to which further selection criteria can be applied by both the installation teams and the end user, such as authorities in Almaty

Worldwide trends in diabetes since 1980: a pooled analysis of 751 population-based studies with 4.4 million participants

BACKGROUND: One of the global targets for non-communicable diseases is to halt, by 2025, the rise in the age-standardised adult prevalence of diabetes at its 2010 levels. We aimed to estimate worldwide trends in diabetes, how likely it is for countries to achieve the global target, and how changes in prevalence, together with population growth and ageing, are affecting the number of adults with diabetes. METHODS: We pooled data from population-based studies that had collected data on diabetes through measurement of its biomarkers. We used a Bayesian hierarchical model to estimate trends in diabetes prevalence—defined as fasting plasma glucose of 7·0 mmol/L or higher, or history of diagnosis with diabetes, or use of insulin or oral hypoglycaemic drugs—in 200 countries and territories in 21 regions, by sex and from 1980 to 2014. We also calculated the posterior probability of meeting the global diabetes target if post-2000 trends continue. FINDINGS: We used data from 751 studies including 4 372 000 adults from 146 of the 200 countries we make estimates for. Global age-standardised diabetes prevalence increased from 4·3% (95% credible interval 2·4–7·0) in 1980 to 9·0% (7·2–11·1) in 2014 in men, and from 5·0% (2·9–7·9) to 7·9% (6·4–9·7) in women. The number of adults with diabetes in the world increased from 108 million in 1980 to 422 million in 2014 (28·5% due to the rise in prevalence, 39·7% due to population growth and ageing, and 31·8% due to interaction of these two factors). Age-standardised adult diabetes prevalence in 2014 was lowest in northwestern Europe, and highest in Polynesia and Micronesia, at nearly 25%, followed by Melanesia and the Middle East and north Africa. Between 1980 and 2014 there was little change in age-standardised diabetes prevalence in adult women in continental western Europe, although crude prevalence rose because of ageing of the population. By contrast, age-standardised adult prevalence rose by 15 percentage points in men and women in Polynesia and Micronesia. In 2014, American Samoa had the highest national prevalence of diabetes (>30% in both sexes), with age-standardised adult prevalence also higher than 25% in some other islands in Polynesia and Micronesia. If post-2000 trends continue, the probability of meeting the global target of halting the rise in the prevalence of diabetes by 2025 at the 2010 level worldwide is lower than 1% for men and is 1% for women. Only nine countries for men and 29 countries for women, mostly in western Europe, have a 50% or higher probability of meeting the global target. INTERPRETATION: Since 1980, age-standardised diabetes prevalence in adults has increased, or at best remained unchanged, in every country. Together with population growth and ageing, this rise has led to a near quadrupling of the number of adults with diabetes worldwide. The burden of diabetes, both in terms of prevalence and number of adults affected, has increased faster in low-income and middle-income countries than in high-income countries. FUNDING: Wellcome Trust

Intra-Crater Eruption Dynamics at Nyiragongo (D.R. Congo), 2002–2021

Nyiragongo is one of the rare volcanoes on Earth hosting a lava lake. However, the understanding of its plumbing and lava lake systems remains limited, with, until recently, only sporadic or time-limited historical observations and measurements. Combining dense accurate lava lake and crater floor level measurements based on 1,703 satellite radar images and topographic reconstructions using photogrammetry, we obtain the first reliable picture and time evolution of intra-crater erupted lava volumes between the two last flank eruptions in January 2002 and May 2021. The filling of the crater by lava, initiated in 2002 and continued up to May 2021, is seen as an evidence of a long-term pressure build up of the magmatic system. This filling occurs through irregular pulsatory episodes of rising lava lake level, some of which overflow and solidify on the surrounding crater floor. Pauses of stable molten lava lake level and sudden numerous level drops also marked the summit's eruptive activity. The joint analysis with seismic records available since 2015 revealed that the largest lava lake drops are synchronous with seismic swarms associated with deep magma intrusions, generally preceded by an increase of extrusion rate within the crater. The appearance of a spatter cone in the summit crater in 2016, most likely superficially branched to the lava lake, was a clear marker of the change in eruption dynamics. This first long-term time series of Nyiragongo's crater topography between two hazardous flank eruptions might further help to better decipher Nyiragongo's past and future behavior using multi-parameter observations