【阅读】02/15起粤督寂静整理(02/26更新，47篇原始，40篇考古）

Kleopatra

女性贷款meeting參考文獻
The Economic Returns to Social Interaction: Experimental Evidence from Microfinance
Authors: Benjamin Feigenberg, Erica Field and Rohini Pande
Abstract
Microfinance clients were randomly assigned to repayment groups that met either weekly or monthly during their first loan cycle, and then graduated to identical meeting frequency for their second loan. Long-run survey data and a follow-up public goods experiment reveal that clients initially assigned to weekly groups interact more often and exhibit a higher willingness to pool risk with group members from their first loan cycle nearly two years after the experiment. They were also three times less likely to default on their second loan. Evidence from an additional treatment arm show that, holding meeting frequency fixed, the pattern is insensitive to repayment frequency during the first loan cycle. Taken together, these findings constitute the first experimental evidence on the economic returns to social interaction, and provide an alternative explanation for the success of the group lending model in reducing default risk.
https://epod.cid.harvard.edu/sites/default/files/2018-02/the_economic_returns_to_social_interaction-_experimental_evidence_from_microfinance.pdf

billyisfragile!

https://www.newscientist.com/article/dn11394-tiny-organisms-remember-the-way-to-food/

17 March 2007
Tiny organisms remember the way to food
By Greg Huang

SOME of the most basic organisms are smarter than we thought. Rather than moving about randomly, amoebas and plankton employ sophisticated strategies to look for food and might travel in a way that optimises their foraging.

Biophysicists have long tried to explain how creatures of all sizes search for food. However, single-celled organisms such as bacteria seem to move in no particular direction in their search.

第一段说学者Liang Li 和某某发现浮游生物转向具有记忆力，第一次向右转，那么下一次向右的概率就会大一倍。而通过植入一种蛋白物质，使其往相反的方向转，这样它能游得更远。

To investigate, Liang Li and Edward Cox at Princeton University studied the movements of amoebas (Dictyostelium) in a Petri dish, recording the paths travelled by 12 amoebas, including every turn and movement straight ahead, for 8 to 10 hours per amoeba.

https://forum.chasedream.com/thread-1340285-1-1.html

一开始讲有些微生物为了food forage(原词， 可以考古)会控制自己的行为。然后讲有两种细菌一种是Amo开头的，它们转右以后就大概率会转左，以保证自己不会一直绕圈圈，增大食物搜寻的范围。另外一种细菌好像是B开头的(?)，也举了个例子但是忘了...

Immediately after an amoeba turned right, it was twice as likely to turn left as right again, and vice versa, they told a meeting of the American Physical Society meeting in Denver, Colorado, last week. This suggests that the cells have a rudimentary memory, being able to remember the last direction they had just turned in, says Robert Austin, a biophysicist at Princeton who was not involved in the study.

Such memories might be laid down because of the way the cell moves. To turn, an amoeba extends part of its body in the preferred direction, which creates a scar made of protein down that side of the cell. The scar might make the cell temporarily more likely to move in the opposite direction. For the amoeba, the pay-off is that it avoids travelling in circles and hence can search a larger area.

第二段说，又有两个人，研究发现一种东西是转36度，说这个角度是最佳的。。。

Another study has shed light on the optimal foraging strategy of micro-organisms. Ricardo Garcia and Frank Moss at the University of Missouri at St Louis placed Daphnia zooplankton (see Picture) in water laced with food particles and measured the angles of up to 1000 turns made by individuals of five different species. The plankton were exponentially more likely to turn at smaller, more gradual angles than larger ones, with a preferred turning angle of about 36 degrees.

Meanwhile, their collaborators at Humboldt University in Berlin, Germany, used a computer model to calculate what angle would maximise the amount of food Daphnia collected within a fixed space and time. It turns out that the optimal turning angle closely matches that used by Daphnia in the experiments (Mathematical Biosciences, in press); and an angle any greater or smaller would make the plankton less successful. “This allows it to explore the most area and get the most food in a given amount of time,” says Garcia.

Q_quant

谢谢

Pupkikity

谢谢

渺小到快要隐形

Louise233

xiexie

yuyuyu94

k看一下