Analysis of Accuracy in Pointing with Redundant Hand-held Tools: A Geometric Approach to the Uncontrolled Manifold Method

This work introduces a coordinate-independent method to analyse movement variability of tasks performed with hand-held tools, such as a pen or a surgical scalpel. We extend the classical uncontrolled manifold (UCM) approach by exploiting the geometry of rigid body motions, used to describe tool configurations. In particular, we analyse variability during a static pointing task with a hand-held tool, where subjects are asked to keep the tool tip in steady contact with another object. In this case the tool is redundant with respect to the task, as subjects control position/orientation of the tool, i.e. 6 degrees-of-freedom (dof), to maintain the tool tip position (3dof) steady. To test the new method, subjects performed a pointing task with and without arm support. The additional dof introduced in the unsupported condition, injecting more variability into the system, represented a resource to minimise variability in the task space via coordinated motion. The results show that all of the seven subjects channeled more variability along directions not directly affecting the task (UCM), consistent with previous literature but now shown in a coordinate-independent way. Variability in the unsupported condition was only slightly larger at the endpoint but much larger in the UCM.     

Effect of weight loss and exercise on angiogenic factors in the circulation and in adipose tissue in obese subjects

Background:

Vascular growth is a prerequisite for adipose tissue (AT) development and expansion. Some AT cytokines and hormones have effects on vascular development, like vascular endothelial growth factor (VEGF‐A), angiopoietin (ANG‐1), ANG‐2 and angiopoietin‐like protein‐4 (ANGPTL‐4).

Methods:

In this study, the independent and combined effects of diet‐induced weight loss and exercise on AT gene expression and proteins levels of those angiogenic factors were investigated. Seventy‐nine obese males and females were randomized to: 1. Exercise‐only (EXO; 12‐weeks exercise without diet‐restriction), 2. Hypocaloric diet (DIO; 8‐weeks very low energy diet (VLED) + 4‐weeks weight maintenance diet) and 3. Hypocaloric diet and exercise (DEX; 8‐weeks VLED + 4‐weeks weight maintenance diet combined with exercise throughout the 12 weeks). Blood samples and fat biopsies were taken before and after the intervention.

Results:

Weight loss was 3.5 kg in the EXO group and 12.3 kg in the DIO and DEX groups. VEGF‐A protein was non‐significantly reduced in the weight loss groups. ANG‐1 protein levels were significantly reduced 22‐25% after all three interventions (P < 0.01). The ANG‐1/ANG‐2 ratio was also decreased in all three groups (P < 0.05) by 27‐38%. ANGPTL‐4 was increased in the EXO group (15%, P < 0.05) and 9% (P < 0.05) in the DIO group. VEGF‐A, ANG‐1, and ANGPTL‐4 were all expressed in human AT, but only ANGPTL‐4 was influenced by the interventions.

Conclusions:

Our data show that serum VEGF‐A, ANG‐1, ANG‐2, and ANGPTL‐4 levels are influenced by weight changes, indicating the involvement of these factors in the obese state. Moreover, it was found that weight loss generally was associated with a reduced angiogenic activity in the circulation.     

YACOP: Enhanced gene prediction obtained by a combination of existing methods

The performance of gene-predicting tools varies considerably if evaluated with respect to the parameters sensitivity and specificity or their capability to identify the correct start codon. We were interested to validate tools for gene prediction and to implement a metatool named YACOP, which combines existing tools and has a higher performance. YACOP parses and combines the output of the three gene-predicting systems Criticia, Glimmer and ZCURVE. It outperforms each of the programs tested with its high sensitivity and specificity values combined with a larger number of correctly predicted gene starts. Performance of YACOP and the gene-finding programs was tested by comparing their output with a carefully selected set of annotated genomes. We found that the problem of identifying genes in prokaryotic genomes by means of computational analysis was solved satisfactorily. In contrast, the correct localization of the start codon still appeared to be a problem, as in all cases under test at least 7.8% and up to 32.3% of the positions given in the annotations differed from the locus predicted by any of the programs tested. YACOP can be downloaded from http://www.g2l.bio.uni-goettingen.de.     

TICO: a tool for improving predictions of prokaryotic translation initiation sites

SUMMARY: We provide the tool 'TICO' (Translation Initiation site COrrection) for improving the results of conventional gene finders for prokaryotic genomes with regard to exact localization of the translation initiation site (TIS). At the current state TICO provides an interface for direct post processing of the predictions obtained from the widely used program GLIMMER. Our program is based on a clustering algorithm for completely unsupervised scoring of potential TIS locations. AVAILABILITY: Our tool can be freely accessed through a web interface at http://tico.gobics.de/ CONTACT: maike@gobics.de     

An unsupervised classification scheme for improving predictions of prokaryotic TIS

Background  

Although it is not difficult for state-of-the-art gene finders to identify coding regions in prokaryotic genomes, exact prediction of the corresponding translation initiation sites (TIS) is still a challenging problem. Recently a number of post-processing tools have been proposed for improving the annotation of prokaryotic TIS. However, inherent difficulties of these approaches arise from the considerable variation of TIS characteristics across different species. Therefore prior assumptions about the properties of prokaryotic gene starts may cause suboptimal predictions for newly sequenced genomes with TIS signals differing from those of well-investigated genomes.     

小头叶蝉属系统分类研究（同翅目：叶蝉科）

记述世界小头叶蝉属Placidus Distant昆虫9种,其中包括4个新种。条痕小头叶蝉Placidus striolatus,sp.nov. 乌樽小头叶蝉Placidus nigrocupuliferou,sp.nov.分布于云省,花顶小头叶蝉Placidus flosifronus,sp.nov.分布于湖南省,密齿小叶蝉Placidus dentatus,sp.nov。分布于四川省。中列出了所有9种小头叶蝉的名录并编制了分布检索表。新种模式标本分别保存于西北农林科技大学昆虫博物馆和中国科学院动物研究所（IZAS）。新种模式标本和示差鉴别特征如下：条痕小叶蝉Placidus striolatus,新种,正模：♂（IZAS）,云南省,大围山,1350m,1956-V-22,邦浦洛夫采。该新种与P.hornei Distant相近,但其雄性生殖瓣侧面观近三角形,尾节侧瓣向后渐狭,阳茎端部近1／3处具数条长印痕,阳茎产端部腹缘锯齿状,可以与后相区别。花顶小头叶蝉Palcidus flosifrontus,新种（图3）,正模♂,南非,郴州莽山,1985－Ⅶ－31,张雅林,柴勇辉采。该新种与P.hornei Distant相近,但其阳茎基部两侧所具有一对长的带状突不同于小头叶蝉属Placidus所有其他种类。密齿小头叶蝉Plasidus dentatus,新种（图4）,模：♂（IZAS）,四川省,马尔康,1961－Ⅵ,李贵富采。该新种与P.brunneus Kuoh相近,但其小盾片中域横刻痕不明显,连索“Y”型,阳茎端部部侧区密生小齿突,可与后明显相区分,乌樽小头叶蝉Placidus nigrocupuliferous,新种（图5）,正模：♂,云南省,勐养,750m,1991-Ⅵ－9,王应伦,田润刚采。该新种与P.hornei Distant和P.bruneus Kuoh相近,但其阳基侧突呈“S”形且基部1／3膨大,阳茎侧面观呈“Y”形,腹面一支明显比背方一支狭,可与后两种明显区分。     

Iron and iron/manganese ratio in forage from Icelandic sheep farms: relation to scrapie

This study was undertaken in order to examine whether any connection existed between the amounts of iron in forage and the sporadic occurrence of scrapie observed in certain parts of Iceland. As iron and manganese are considered antagonistic in plants, calculation of the Fe/Mn ratios was also included by using results from Mn determination earlier performed in the same samples. Forage samples (n = 170) from the summer harvests of 2001–2003, were collected from 47 farms for iron and manganese analysis. The farms were divided into four categories: 1. Scrapie-free farms in scrapie-free areas (n = 9); 2. Scrapie-free farms in scrapie-afflicted areas (n = 17); 3. Scrapie-prone farms (earlier scrapie-afflicted, restocked farms) (n = 12); 4. Scrapie-afflicted farms (n = 9). Farms in categories 1 and 2 are collectively referred to as scrapie-free farms. The mean iron concentration in forage samples from scrapie-afflicted farms was significantly higher than in forage samples from farms in the other scrapie categories (P = 0.001). The mean Fe/Mn ratio in forage from scrapie-afflicted farms was significantly higher than in forage from scrapie-free and scrapie-prone farms (P < 0.001). The results indicated relative dominance of iron over manganese in forage from scrapie-afflicted farms as compared to farms in the other categories. Thus thorough knowledge of iron, along with manganese, in soil and vegetation on sheep farms could be a pivot in studies on sporadic scrapie.