Influence of cultivar, harvest time, storage conditions, and peeling on the antioxidant capacity and phenolic and ascorbic acid contents of apples and pears

Apple and pear fruits are important sources of secondary plant metabolites and one of the major sources of dietary phenolics consumed all year round. The aim of this work was to identify the main variables influencing phenolic content and antioxidant capacity in apples. Higher phenolic and antioxidant contents were observed in some varieties (such as the Delbar Estival apple and Durondeau pear). Storage conditions were important. Our results also showed that fruits should be consumed rapidly after purchase and with their peel. After one week of domestic storage, the ascorbic acid content was found to decrease by 75%. Peeling led to a more than 25% decrease in total phenolics and ascorbic acid. The harvest time (at normal ripeness) had only a limited impact, but significant year-to-year variations were observed. In conclusion, well-chosen and well-stored apples and pears may contribute to an antioxidant-rich diet if consumed rapidly and with their peel.     

SCINTIGRAPHIC EVALUATION OF THE STIFLE IN NORMAL HORSES AND HORSES WITH FORELIMB LAMENESS

We tested the hypotheses that mature horses without lameness have a repeatable radiopharmaceutical uptake pattern in the stifle, which is bilaterally symmetric; immature horses have a different radiopharmaceutical uptake pattern; and forelimb lameness alters the radiopharmaceutical uptake pattern in the stifle. The objectives of the study were to describe the normal radiopharmaceutical uptake patterns using region of interest (ROI) analysis; to compare uptake patterns between left and right stifles of the same horse and between mature and immature horses; to compare radiopharmaceutical uptake in mature normal horses with those with forelimb lameness. Lateral scintigraphic images of the stifle from 51 horses aged 2-16 years were evaluated using seven ROIs and a reference site (midfemur). After subtraction of a background count, ratios between the mean counts per pixel for each ROI to the reference site were calculated. There was a repeatable radiopharmaceutical uptake pattern in mature normal horses that was bilaterally symmetrical. The caudoproximal aspect of the tibia and the patella had the highest ratios. Radiopharmaceutical uptake patterns in horses with forelimb lameness were not significantly different. Immature normal horses had a different symmetric pattern, with greatest radiopharmaceutical uptake ratios in the caudoproximal aspect of the tibia and the tibial crest. It was concluded that there are symmetric, repeatable radiopharmaceutical uptake patterns in both immature and mature horses, which are not altered by forelimb lameness.     

Antioxidant capacity of black currant varies with organ, season, and cultivar

Small berries such as black currant constitute one of the important sources of potential health-promoting phytochemicals because these fruits are rich sources of compounds with high antioxidant properties. In this work, antioxidant capacities of different parts (buds, leaves, fruits) of various black currant cultivars were compared throughout the growing season with the aim to prepare extracts with high antioxidant capacity. Buds (opened, at the end of March) and leaves (in June) had a higher content in phenolics and antioxidants than fully ripened berries (in July) and the best yield (per branch) was obtained with the leaves collected in June due to their higher biomass. The differences observed among the eight cultivars tested were small. Concerning flavonols, quercetin was dominant in all organs and cultivars, myricetin varied widely among the cultivars, and kampferol was very low.     

Evolution of antioxidant capacity during storage of selected fruits and vegetables

Interest in the consumption of fresh fruits and vegetables is, to a large extent, due to its content of bioactive nutrients and their importance as dietary antioxidants. Among all of the selected fruits and vegetables, strawberries and black grapes have relatively high antioxidant capacities associated with high contents of total phenolic compounds, ascorbic acid, and flavonols. More interesting, the results of this study indicated that in most fruits and vegetables storage did not affect negatively the antioxidant capacity. Better, in some cases, an increase of the antioxidant capacity was observed in the days following their purchase, accompanied by an increase in phenolic compounds. In general, fruits and vegetables visually spoil before any significant antioxidant capacity loss occurs except in banana and broccoli. When ascorbic acid or flavonoids (aglycons of flavonols and anthocyanins) were concerned, the conclusions were similar. Their content was generally stable during storage.     

水稻RIL群体高密度遗传图谱的构建及苗期耐热性QTL定位

【目的】 随着全球气候变暖,高温严重威胁粮食安全,发掘耐热基因资源是培育耐高温新品种和消除高温危害最直接的绿色生态途径,也是阐明耐热生理生化和分子遗传机理的基础。【方法】 构建苗期耐热性鉴定评价方法,以热敏感品种周南稻和强耐热品种赣早籼58号杂交衍生的重组自交系（recombinant inbred lines,RIL）群体为研究材料,利用高通量测序技术对亲本和RIL群体进行全基因组测序;依据171个家系的基因型数据,利用滑动窗口法将SNP信息转换成Bin基因型,预测染色体上的重组断点,构建RIL群体高密度BinMap遗传图谱,结合耐热表型数据,运用QTL IciMapping软件完备复合区间ICIM的作图方法,进行高温胁迫下幼苗存活率和耐热等级QTL分析。【结果】 构建了一张包含3 321个Bin标记高密度遗传图谱,各染色体Bin标记数为159—400个,标记间平均物理距离为106 kb;利用逐步高温胁迫方式鉴定亲本和RIL家系幼苗耐热表型,高温胁迫下,幼苗存活率和耐热等级存在极显著负相关性,且幼苗存活率与籼型基因频率存在显著正相关性,籼型基因频率越高,耐热性越好,RIL群体表型性状呈现双峰连续分布,苗期耐热性可能受少数几个主效QTL调控;共检测到12个苗期耐热性相关的QTL,其中,调控幼苗存活率和耐热等级的QTL分别有8和4个,幼苗存活率和耐热等级相关QTL存在遗传重叠现象,形成调控耐热性的主效QTL簇qHTS2、qHTS7和qHTS8,三者在调控苗期高温抗逆中具有重要作用,其中,qHTS7为新发现主效QTL,对增强苗期耐热性具有较强的功效。【结论】 构建了一张包含3 321个Bin标记的高密度分子遗传图谱,解析了耐热品种赣早籼58号苗期耐热基因,鉴定出3个苗期耐热调控关键QTL簇,发掘了一个新主效QTL簇qHTS7,基于高密度遗传图谱高效获取目标区段及候选基因,筛选出8个苗期耐热性调控的关键目标基因。     

Diffuse Extreme-Ultraviolet Emission from the Coma Cluster: Evidence for Rapidly Cooling Gases at Submegakelvin Temperatures

The central region of the Coma cluster of galaxies was observed in the energy band from 0.065 to 0.245 kiloelectron volts by the Deep Survey telescope aboard the Extreme Ultraviolet Explorer. A diffuse emission halo of angular diameter approximately 30 arc minutes was detected. The extreme-ultraviolet (EUV) emission level exceeds that expected from the x-ray temperature gas in Coma. This halo suggests the presence of two more phases in the emitting gas, one at a temperature of approximately 2 x 10(6) kelvin and the other at approximately 8 x 10(5) kelvin. The latter phase cools rapidly and, in steady state, would have produced cold matter with a mass of approximately 10(14) solar masses within the EUV halo. Although a similar EUV enhancement was discovered in the Virgo cluster, this detection in Coma applies to a noncooling flow system.     

The first case of genetically confirmed monozygotic twinning in the dog

Monozygotic twinning has not previously been genetically confirmed in the dog. This case report describes the finding of two viable male monozygotic foetuses within one placental site during caesarean section. Their umbilical cords attached to a single placenta. Genetic profiling using a total of 38 microsatellite markers, as well as amelogenin and SRY for sex determination, revealed identical DNA profiles, whether derived from blood or tissue (buccal swabs) samples. To the best of our knowledge, this is the first report of monozygotic twinning in the dog confirmed using DNA profiling.     

The toxicity of Castanospermum australe seeds for cattle

Two calves given a mean of 16.1 g and 16.4 g ripe Castanospermum australe seeds/kg body weight daily for 13 and 16 days respectively developed haemorrhagic gastroenteritis. The first calf died. The second calf had mild myocardial degeneration and necrosis and mild nephrosis at necropsy. Two calves given a mean of 16.8 g unripe C. australe seeds/kg body weight daily for 18 days remained clinically normal and had mild gastritis at necropsy. The activity of alpha-glucosidase was reduced in the mononuclear cells of peripheral blood and in skeletal muscle. This was attributed to the presence of the indolizidine alkaloid, castanospermine, in the seeds. The toxin causing the gastroenteritis and other lesions is unknown.     

Stormy weather in galaxy clusters

Recent x-ray, optical, and radio observations coupled with particle and gas dynamics numerical simulations reveal an unexpectedly complex environment within clusters of galaxies, driven by ongoing accretion of matter from large-scale supercluster filaments. Mergers between clusters and continuous infall of dark matter and baryons from the cluster periphery produce long-lived "stormy weather" within the gaseous cluster atmosphere-shocks, turbulence, and winds of more than 1000 kilometers per second. This weather may be responsible for shaping a rich variety of extended radio sources, which in turn act as "barometers" and "anemometers" of cluster weather.