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Emerging potential of progranulin-dependent SorCS2 signaling in healthy and diseased nervous systems

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Neural Regeneration Research 2025年第9期20卷 2591-2593页

作者： Alena Salasova anders Nykjær Danish Research Institute of Translational Neuroscience DANDRITE-Nordic EMBL Partnership for Molecular Medicine and Centre of Excellence PROMEMODepartment of BiomedicineAarhus UniversityAarhusDenmark

The formation of the mammalian nervous system and its maturation into sensory,motor,cognitive,and behavioral circuits is a complex process that begins during early embryogenesis and lasts until young *** neurodevelopm... 详细信息

关键词： progr jointly CS2

Why are sexually selected weapons almost absent in females？

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Current Zoology 2013年第4期59卷 564-568页

作者： anders BERGLUND Department of Ecology and Genetics/Animal Ecology Uppsala University Norbyv. 18d 752 36 Uppsala Sweden

In sex role reversed species, predominantly females evolve sexually selected traits, such as ornaments and/or weapons. Female ornaments are common and their function well documented in many species, whether sex role reversed or not. However, sexually selected female weapons seem totally absent except for small wing spurs in three jacana species, present in both males and females. This poor female weaponry is in sharp contrast to the situation in species with conventional sex roles： males com- monly have evolved sexually selected weapons as well as ornaments. At the same time, females in many taxa have naturally se- lected weapons, used in competition over resources or in predator defence. Why are sexually selected weapons then so rare, al- most absent, in females？ Here I briefly review weaponry in females and the function of these weapons, conclude that the near ab- sence of sexually selected weapons begs an explanation, and suggest that costs of sexually selected weapons may exceed costs of ornaments. Females are more constrained when evolving sexually selected traits compared to males, at least compared to those males that do not provide direct benefits, as trait costs reduce a female＇s fecundity. I suggest that this constraining trade-off between trait and fecundity restricts females to evolve ornaments but rarely weapons. The same may apply to paternally investing males. Whether sexually selected weapons actually are more costly than sexually selected ornaments remains to be investigated

关键词： Sexual selection Female weapons Female ornaments Sex role reversal

Extreme climatic events in relation to global change and their impact on life histories

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Current Zoology 2011年第3期57卷 375-389页

作者： Juan MORENO anders Pape Moller Departamento de Ecologia Evolutiva Museo Nacional de Ciencias Naturales-CSIC C/Jod Gutierrez Abascal 2 E-28006 Madrid Spain Laboratoire d'Ecologie Systematique et Evolution CNRS UMR 8079 Universite Paris-Sud Bfttiment 362 F-91405 Orsay Cedex Franc

Extreme weather conditions occur at an increasing rate as evidenced by higher frequency of hurricanes and more extreme precipitation and temperature anomalies. Such extreme environmental conditions will have important implications for all living organisms through greater frequency of reproductive failure and reduced adult survival. We review examples of reproductive failure and reduced survival related to extreme weather conditions. Phenotypic plasticity may not be sufficient to allow adaptation to extreme weather for many animals. Theory predicts reduced reproductive effort as a response to increased stochasticity. We predict that patterns of natural selection will change towards truncation selection as environmental conditions become more extreme. Such changes in patterns of selection may facilitate adaptation to extreme events. However, effects of selection on reproductive effort are difficult to detect. We present a number of predictions for the effects of extreme weather conditions in need of empirical tests. Finally, we suggest a number of empirical reviews that could improve our ability to judge the effects of extreme environmental conditions on life history [Current Zoology 57 （3）： 375-389, 2011].

关键词： Bet hedging Climate change Extreme weather Reproductive failure Truncation selection

Bottom-up approaches to microLEDs emitting red, green and blue light based on GaN nanowires and relaxed InGaN platelets

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Chinese Physics B 2023年第1期32卷 1-10页

作者：毕朝霞 anders Gustafsson Lars Samuelson anders Gustafsson and Lars Samuelson Division of Solid State Physics and NanoLundLund UniversityBox 118SE-22100 LundSweden

Miniaturization of light-emitting diodes(LEDs) with sizes down to a few micrometers has become a hot topic in both academia and industry due to their attractive applications on self-emissive displays for high-definition televisions,augmented/mixed realities and head-up displays, and also on optogenetics, high-speed light communication, etc. The conventional top-down technology uses dry etching to define the LED size, leading to damage to the LED side *** sizes of microLEDs approach the carrier diffusion length, the damaged side walls play an important role, reducing microLED performance significantly from that of large area LEDs. In this paper, we review our efforts on realization of microLEDs by direct bottom-up growth, based on selective area metal–organic vapor phase epitaxy. The individual LEDs based on either GaN nanowires or InGaN platelets are smaller than 1 μm in our approach. Such nano-LEDs can be used as building blocks in arrays to assemble microLEDs with different sizes, avoiding the side wall damage by dry etching encountered for the top-down approach. The technology of InGaN platelets is especially interesting since InGaN quantum wells emitting red, green and blue light can be grown on such platelets with a low-level of strain by changing the indium content in the InGaN platelets. This technology is therefore very attractive for highly efficient microLEDs of three primary colors for displays.

关键词： microLEDs RGB GaN InGaN

Biological consequences of global change for birds

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Integrative Zoology 2013年第2期8卷 136-144页

作者： anders Pape MØLLER Department of Ecology Systematics and EvolutionUniversity Paris-SouthOrsay CedexFrance

Climate is currently changing at an unprecedented rate;so also human exploitation is rapidly changing the Earth for agriculture,forestry,fisheries and *** addition,pollution has affected even the most remote ecosystems,as has the omnipresence of humans,with consequences in particular for animals that keep a safe distance from potential predators,including human ***,all of these changes are occurring simultaneously,with increasing intensity,and further deterioration in both the short and the long-term is *** the consequences of these components of global change are relatively well studied on their own,the effects of their interactions,such as the combined effects of climate change and agriculture,or the combined effects of agriculture through nutrient leakage to freshwater and marine ecosystems and fisheries,and the effects of climate change and urbanization,are poorly ***,I provide a brief overview of the effects of climate change on phenology,diversity,abundance,interspecific interactions and population dynamics of birds.I address whether these effects of changing temperatures are direct,or indirect through effects of climate change on the phenology,distribution or abundance of food,parasites and ***,I review interactions between different components of global change.

关键词： climate change direct effects global change indirect effects interactions

Climate-Induced Variability of Sea Level in Stockholm: Influence of Air Temperature and Atmospheric Circulation

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Advances in Atmospheric Sciences 2005年第5期22卷 655-664页

作者： Deliang CHEN anders OMSTEDT Earth Sciences Centre Goteborg University Sweden Laboratory for Climate Studies/National Climate Center China Meteorological Administration Beijing 100081

This study is focused on climate-induced variation of sea level in Stockholm during 1873-1995. After the effect of the land uplift, is removed, the residual is characterized and related to large-scale temperature and atmospheric circulation. The residual shows an overall upward trend, although this result depends on the uplift rate used. However, the seasonal distribution of the trend is uneven. There are even two months （June and August） that show a negative trend. The significant trend in August may be linked to fresh water input that is controlled by precipitation. The influence of the atmospheric conditions on the sea level is mainly manifested through zonal winds, vorticity and temperature. While the wind is important in the period January-May, the vorticity plays a main role during June and December. A successful linear multiple-regression model linking the climatic variables （zonal winds, vorticity and mean air temperature during the previous two months） and the sea level is established for each month. An independent verification of the model shows that it has considerable skill in simulating the variability.

关键词： sea level Baltic sea atmospheric circulation temperature Stockholm

Methods of modeling relative growth rate

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Forest Ecosystems 2015年第2期2卷 82-90页

作者： Arne Pommerening anders Muszta Department of Forest Resource Management Faculty of Forest SciencesSwedish University of Agricultural Sciences SLU

Background： Analysing and modelling plant growth is an important interdisciplinary field of plant science. The use of relative growth rates, involving the analysis of plant growth relative to plant size, has more or less independently emerged in different research groups and at different times and has provided powerful tools for assessing the growth performance and growth efficiency of plants and plant populations. In this paper, we explore how these isolated methods can be combined to form a consistent methodology for modelling relative growth rates. Methods： We review and combine existing methods of analysing and modelling relative growth rates and apply a combination of methods to Sitka spruce （Piceo sitchensis （Bong.） Carr.） stem-analysis data from North Wales （UK） and British Douglas fir （Pseudotsugd menziesii （Mirb.） Franco） yield table data. Results： The results indicate that, by combining the approaches of different plant-growth analysis laboratories and using them simultaneously, we can advance and standardise the concept of relative plant growth. Particularly the growth multiplier plays an important role in modelling relative growth rates. Another useful technique has been the recent introduction of size-standardised relative growth rates. Conclusions： Modelling relative growth rates mainly serves two purposes, 1） an improved analysis of growth performance and efficiency and 2） the prediction of future or past growth rates. This makes the concept of relative growth ideally suited to growth reconstruction as required in dendrochronology, climate change and forest decline research and for interdisciplinary research projects beyond the realm of plant science.

关键词： Growth efficiency Growth coefficient/multiplier Chapman-Richards growth model Standardisation Simultaneous estimations

DATA PREORDERING IN GENERALIZED PAV ALGORITHM FOR MONOTONIC REGRESSION

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Journal of Computational Mathematics 2006年第6期24卷 771-790页

作者： Oleg Burdakov anders Grimvall Oleg Sysoev Department of Mathematics LinkSping University SE-58183 Link6ping Sweden

Monotonic regression （MR） is a least distance problem with monotonicity constraints induced by a partiaily ordered data set of observations. In our recent publication [In Ser. Nonconvex Optimization and Its Applications, Springer-Verlag, （2006） 83, pp. 25-33], the Pool-Adjazent-Violators algorithm （PAV） was generalized from completely to partially ordered data sets （posets）. The new algorithm, called CPAV, is characterized by the very low computational complexity, which is of second order in the number of observations. It treats the observations in a consecutive order, and it can follow any arbitrarily chosen topological order of the poset of observations. The CPAV algorithm produces a sufficiently accurate solution to the MR problem, but the accuracy depends on the chosen topological order. Here we prove that there exists a topological order for which the resulted CPAV solution is optimal. Furthermore, we present results of extensive numerical experiments, from which we draw conclusions about the most and the least preferable topological orders.

关键词： Quadratic programming Large scale optimization Least distance problem,Monotonic regression Partially ordered data set Pool-adjacent-violators algorithm.

Characterization of force networks in a dense high-shear system

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Particuology 2018年第3期16卷 215-221页

作者： Mohammad Khalilitehrani Srdjan Sasic anders Rasmuson Department of Chemistry and Chemical Engineering Chalmers University of Technology SE-412 96 Goteborg Sweden Department of Applied Mechanics Chalmers University of Technology SE-412 96 Gteborg Sweden

We detect strong force networks in a dense high-shear system and study their structure and stability in response to variations in the shearing rate. The presence of strong force networks, which usually have a heterogeneous structure, restricts particle movements and can impose non-local mechanisms of momentum transfer. We identify such networks in a dense high-shear system using a community detec- tion algorithm. Moreover, we explain the association between the mechanisms of momentum transfer and the structure, population, strength, and stability of the force networks by tracking the spatial and temporal evolution of the detected networks. In addition, we show that the assumption of a monodis- perse assembly of particles leads to an unrealistic enlargement of the force networks, underestimating both the rate of energy dissipation and the rate of mixing.

关键词： Force networks Community detection Polydispersity