Two-dimensional generalisations of dynamic programming for image analysis

Dynamic programming (DP) is a fast, elegant method for solving many one-dimensional optimisation problems but, unfortunately, most problems in image analysis, such as restoration and warping, are two-dimensional. We consider three generalisations of DP. The first is iterated dynamic programming (IDP), where DP is used to recursively solve each of a sequence of one-dimensional problems in turn, to find a local optimum. A second algorithm is an empirical, stochastic optimiser, which is implemented by adding progressively less noise to IDP. The final approach replaces DP by a more computationally intensive Forward-Backward Gibbs Sampler, and uses a simulated annealing cooling schedule. Results are compared with existing pixel-by-pixel methods of iterated conditional modes (ICM) and simulated annealing in two applications: to restore a synthetic aperture radar (SAR) image, and to warp a pulsed-field electrophoresis gel into alignment with a reference image. We find that IDP and its stochastic variant outperform the remaining algorithms.     

A randomized,double-blind,placebo-controlled trial of testosterone gel on body composition and health-related quality-of-life in men with hypogonadal to low-normal levels of serum testosterone and symptoms of androgen deficiency over 6 months with 12 months open-label follow-up

Introduction: The clinical significance of low to low-normal testosterone (T) levels in men remains debated. Aim: To analyze the effects of raising serum T on lean body mass (LBM), fat mass (FM), total body mass, and health-related quality-of-life (HRQoL). Methods: Randomized, double-blind, placebo-controlled study. Men, aged 50–80 years, with serum total T<15 nmol/L and bioavailable T < 6.68 nmol/L, and a Aging Males’ Symptoms (AMS) total score >36, received 6 months treatment with transdermal 1% T gel (5–7.5?mg/day; n =183) or placebo gel (n =179), followed by 12 months open-label with T in all. Results: After 6 months, LBM increased in T- treated patients by 1.28?±?0.15?kg (mean ± SE) and FM decreased by 1.16?±?0.16?kg, with minor changes with placebo (LBM +0.02?±?0.10?kg and FM ?0.14?±?0.12?kg; all p < 0.001, T group vs. placebo). Changes were largely similar across subgroups of age, baseline total testosterone, and baseline BMI. Total HRQoL improved compared with placebo (p < 0.05, T group vs. placebo). Conclusions: Six months 1% T gel improved body composition and HRQoL in symptomatic men with low to low-normal T, with further improvements over the following 12 months.     

改良测序聚丙烯酰胺凝胶和普通聚丙烯酰胺凝胶技术在玉米分子标记中的应用研究

为了快速、低成本获得高质量的玉米基因组DNA分子标记检测技术,在借鉴其他作物常规DNA分子标记检测的基础上,摸索了一套包括DNA提取及综合利用测序和普通聚丙烯酰胺凝胶电泳技术等DNA标记检测高效方法。以玉米为试验材料,提取其基因组DNA,选择不同玉米分子标记,并将标记扩增产物进行聚丙烯酰胺凝胶电泳,然后硝酸银染色,最终建立了一种应用于玉米分子标记的DNA提取和PAGE银染检测方法。在玉米DNA提取改良方面,本研究通过当天取玉米幼叶,立即利用电钻低温0⁴℃磨样,并减少1次抽提过程,结果显示提取DNA质量较好。在此基础上利用普通聚丙烯酰胺凝胶电泳检测PCR扩增结果,在优化部分参数后,检测效果依然较好;对其较难检测的差异过小的片段,通过改良的测序凝胶电泳检测,检测结果多态明显,且条带易读,灵敏度及分辨率均比普通聚丙烯酰胺凝胶电泳高。通过改良玉米DNA提取方法及综合利用测序和普通聚丙烯酰胺凝胶电泳技术,建立了一种行之有效、简便快捷的玉米分子标记应用研究技术。     

硅胶基吸附材料的合成方法

硅胶基吸附材料是以硅胶为基质合成的一种对金属离子具有良好吸附性能的材料．本文从改性机理和合成路径两方面综述了硅胶基吸附材料的合成方法,并讨论了不同合成路径（异相法、均相法、共聚法）的优缺点．     

Testosterone therapy - what,when and to whom?

Testosterone therapy has been used for more than 60 years in the treatment of male hypogonadism. The classical forms of hypogonadism are comprised of primary testicular failure or insufficient testicular stimulation due to the lack of pituitary gonadotropins. Typical causes of primary hypogonadism are Klinefelter's syndrome, anorchia or acquired disturbances of testicular function. Secondary hypogonadism is characterized by insufficient production of pituitary gonadotropins, due either to pituitary failure or defects at the hypothalamic level. It is unequivocally accepted in clinical practice that any male with inadequately low testosterone production for his age will require androgen therapy. In addition to the classical forms of hypogonadism, the past decade of research has clearly demonstrated that, with increasing age, many men will suffer from decreasing testosterone production. About 15-25% of men over the age of 50 years will experience serum testosterone levels well below the threshold considered normal for men between 20 and 40 years of age. Studies substituting testosterone in elderly men with low serum testosterone have shown that men with clinical symptoms identical to the symptomatology of classical hypogonadism will benefit most from such therapy. Therefore, it is the general consensus to treat men with age-related hypogonadism only when clinical symptoms are present that can be potentially corrected by testosterone administration. Until recently, intramuscular injections of esters, such as testosterone enanthate, have been the mainstay of testosterone therapy. The introduction of testosterone patches has not challenged this approach, since many users of patches suffer from moderate to severe skin reactions. Some oral testosterone formulations have proven to be problematic, as absorption can be variable, bioavailability is frequently poor, due to the first-pass effect of the liver, and frequent administration is often required&lt;citeref rid="b1"&gt;&lt;emph&gt;¹&lt;/emph&gt;&lt;/citeref&gt;. Oral testosterone undecanoate avoids, at least partially, the first-pass effect of the liver. However, plasma testosterone levels generally undergo large fluctuations&lt;citeref rid="b2"&gt;&lt;emph&gt;²&lt;/emph&gt;&lt;/citeref&gt;. The large fluctuations in serum testosterone levels caused by conventional intramuscular injections result in unsatisfactory shifts in mood and sexual function in some men, which, combined with the frequency of injections, make the intramuscular mode of delivery far from ideal. Recently, a hydroalcoholic gel containing 1% testosterone has proven to be as efficient as a testosterone patch, but with fewer side-effects and a higher grade of patient satisfaction&lt;citeref rid="b3"&gt;&lt;emph&gt;³&lt;/emph&gt;&lt;/citeref&gt;^-&lt;citeref rid="b4"&gt;&lt;/citeref&gt;&lt;citeref rid="b5"&gt;&lt;emph&gt;⁵&lt;/emph&gt;&lt;/citeref&gt;. Doses of 50-100 mg gel applied once daily on the skin deliver sufficient amounts of testosterone to restore normal hormonal values and correct the signs and symptoms of hypogonadism. The gel has been shown to be effective and successful in patients in the United States, who have benefited from its availability for almost 3 years. In the near future, intramuscular injections of testosterone undecanoate will become commercially available. Such injections have a very favorable pharmacokinetic profile, with one injection every 3 months maintaining serum testosterone well within the normal range. In phase III studies, intramuscular testosterone undecanoate proved to be as efficient as testosterone enanthate, with only one-quarter of the number of injections required and more stable serum testosterone levels. Thus, the new application modes - hydroalcoholic gel (for example, Testogel®, Schering AG, Germany) and intramuscular testosterone undecanoate (Nebido®, Schering AG, Germany) - appear to be the methods of choice in the near future, one being very suitable for hormone therapy in elderly men, the other for long-term substitution in classical forms of hypogonadism.     

PET/SiO2/TiO2纳米复合材料的合成及其光降解性能研究

采用溶胶-凝胶法制备了聚对苯二甲酸乙二醇酯（PET）／二氧化硅（SiO2）／二氧化钛（TiO2）纳米复合材料,利用红外光谱（IR）、乌氏黏度计表征了该复合材料的分子结构和特性黏度,并测定其在紫外光下的光降解性能．实验表明,PET／SiO2／TiO2体系中存在Si—O—Ti键,并与PET基体作用形成PET／SiO2／TiO2纳米复合材料;该复合材料的特性黏度随体系中SiO2-TiO2含量增加而降低;在紫外光下,SiO2和Ti02纳米颗粒的引入可有效地提高PET的光降解性能．     

共混胶高温堵剂实验室研究

钠粘土与AM单体共混，在130℃下与引发剂和交联剂反应生成了共混胶。该共混胶体系中含钠土6%，单体AM 6%～7%，引发剂Y 100～200mg/L，交联剂J 1%～1.5%。钠土的加入，延缓了成胶时间，提高了热稳定性。该共混胶强度高，封堵能力强，高温堵水应用前景良好。     

六种荞麦过氧化物酶同工酶研究初报

用聚丙烯酰胺凝胶柱状电泳测定滑源苦荞、蒙８７、大黑三棱、８３—２３０、辽源一７３和美国甜荞六种荞麦的过氧化物酶同工酶，结果表明：其酶谱带依次为五、五、三、三、三、二条，平均相对迁移率分别为０．３１０、０．２８９、０．２９７、０．２７６、０．２８８和０．３８０．据此．可得出：美国甜荞与前五种荞麦的地理起源和亲缘关系较远，而前五种亲缘关系较近，但又确有遗传差异．在抗病能力上．８３—２３０＞辽源—７３＞蒙—８７＞大黑三棱＞滑源苦荞＞美国甜荞．在抗寒能力上，滑源苦荞和蒙—８７最耐寒，大黑三棱、８３—２３０和辽源—７３的耐寒性稍弱，而美国甜荞的耐寒力最差．     

凝胶色谱图象计算机分析技术用于DNA检测的实验研究

用计算机图象分析技术对凝胶色谱图象进行分析从而获得DNA分子量和其它参数 构成了数字化凝胶色谱图象计算机系统分析系统。本文介绍了该项技术的实验仪器构成、工作原理及国内外有关的最新发展情况 并结合临床实验给出了实验分析结果。     

利用工业废硅胶制活性白炭黑

工业废硅胶用一定浓度的氢氧化钠处理，经过滤得水玻璃．在其中同时加入氯化钠溶液和稀硫酸，经酸化、过滤、水洗、干燥得活性白炭黑，产品指标和橡胶补强性能均达到有关标准.