北票喇嘛洞墓地魏晋十六国时期人骨的错(牙合)畸形

本文选择辽宁北票喇嘛洞墓地魏晋十六国时期人骨中牙列较完整的个体进行了错He畸形的调查。初步探讨了我国魏晋十六国时期古代居民中错He畸形的发病情况,结果显示：1)辽宁北票喇嘛洞墓地魏晋十六国时期人骨错He畸形的患病率为42．53％;在错He个体中,前牙拥挤所占比例最大,为56．76％;在Angle氏错He分类中,AngleⅠ类所占比例最大,为70．27％;2)错He畸形的患病率性别差异无统计学意义;3)人类经济类型所决定的饮食结构的改变与错He畸形的发病原因有关系。     

Adult spawners: A critical period for subarctic Chinook salmon in a changing climate

Concurrent, distribution-wide abundance declines of some Pacific salmon species, including Chinook salmon (Oncorhynchus tshawytscha), highlights the need to understand how vulnerability at different life stages to climate stressors affects population dynamics and fisheries sustainability. Yukon River Chinook salmon stocks are among the largest subarctic populations, near the northernmost extent of the species range. Existing research suggests that Yukon River Chinook salmon population dynamics are largely driven by factors occurring between the adult spawner life stage and their offspring's first summer at sea (second year post-hatching). However, specific mechanisms sustaining chronic poor productivity are unknown, and there is a tremendous sense of urgency to understand causes, as declines of these stocks have taken a serious toll on commercial, recreational, and indigenous subsistence fisheries. Therefore, we leveraged multiple existing datasets spanning parent and juvenile stages of life history in freshwater and marine habitats. We analyzed environmental data in association with the production of offspring that survive to the marine juvenile stage (juveniles per spawner). These analyses suggest more than 45% of the variability in the production of juvenile Chinook salmon is associated with river temperatures or water discharge levels during the parent spawning migration. Over the past two decades, parents that experienced warmer water temperatures and lower discharge in the mainstem Yukon River produced fewer juveniles per spawning adult. We propose the adult spawner life stage as a critical period regulating population dynamics. We also propose a conceptual model that can explain associations between population dynamics and climate stressors using independent data focused on marine nutrition and freshwater heat stress. It is sobering to consider that some of the northernmost Pacific salmon habitats may already be unfavorable to these cold-water species. Our findings have immediate implications, given the common assumption that northern ranges of Pacific salmon offer refugia from climate stressors.     

Oral pathology patterns in late farmers of the Central Andes: A comparative perspective between coastal and highland populations

Aiming at future comparisons with earlier hunter-gatherers or transitional populations, this paper intends to characterize and describe the oral pathology pattern of late agriculturalists from Central Andes dating to the Late Intermediate Period (LIP) and Inca periods (1000–1532 CE), and identify differences and/or similarities between coastal and highland populations. Although the botanical inventories of the LIP suggest carbohydrate-rich diets and similar components, it has been hypothesized that coastal and highland populations had, nevertheless, substantially different oral pathology patterns. We evaluated 14 indicators of oral pathology from Los Pinos (n = 200) and Armatambo (n = 25) sites in the Central Coast and two chronological phases from Laguna de los Cóndores site (LC-Inca, n = 23; and LC-LIP, n = 55), in the Peruvian northern highlands. The results showed a recurrent pattern of oral pathologies characterized by cervical caries (above 30%), extra-occlusal caries (above 60%), high rates of gross-gross caries, high frequency of ante mortem tooth loss, and signals of periodontal disease among these four populations. The diets of the coast were slightly more abrasive than those of the highlands. Oral pathology patterns were compatible with a slightly more cariogenic diet in the coast than in the highlands. In all four populations, those patterns were modulated by other common factors such as consumption of fermented drinks (maize beer – chicha) and the coca leaf chewing habit.     

Narrow rows reduce biomass and seed production of weeds and increase maize yield

Smallholder farmers in southern African countries rely primarily on cultural control and hoe weeding to combat weeds, but often times, they are unable to keep up with the weeding requirements of the crop because of its laboriousness, causing them to incur major yield losses. Optimisation of crop planting pattern could help to increase yield and suppress weeds and to reduce the critical period of weed control and the weeding requirements to attain maximum yield. Experiments were carried out in Zimbabwe during two growing seasons to assess the effect of maize density and spatial arrangement on crop yield, growth and seed production of weeds and to determine the critical period for weeding. Planting maize at 60 cm row distance achieved higher yields and better weed suppression than planting at 75 or 90 cm row distance. Increasing crop densities beyond the customary three to four plants m⁻² gave modest reductions in weed biomass but also diminished crop yields, probably because of increased competition for water and nutrient resources. Maize planted in narrow rows (60 cm) intercepted more radiation and suffered less yield reduction from delaying hoe weeding than those planted in wider rows (75 or 90 cm), and the duration of the weed-free period required to attain maximum grain yield was 3 weeks shorter in the narrow spacing than that in the 75- and 90-cm row spacings. Weeding was more effective in curtailing weed seed production in the narrow row spatial arrangements than in the wide row planting. The results of these studies show that narrow row spacings may reduce weeding requirements and increase yields.     

Intra‐ and interspecific divergence in the nuclear sequences of the clock gene period in species of the Drosophila buzzatii cluster

We have measured nucleotide variation in the CLOCK/CYCLE heterodimer inhibition domain (CCID) of the clock X‐linked gene period in seven species belonging to the Drosophila buzzatii cluster, namely D. buzzatii, Drosophila koepferae, Drosophila antonietae, Drosophila serido, Drosophila gouveai, Drosophila seriema and Drosophila borborema. We detected that the purifying selection is the main force driving the sequence evolution in period, in agreement with the important role of CCID in clock machinery. Our survey revealed that period provides valuable phylogenetic information that allowed to resolve phylogenetic relationships among D. gouveai, D. borborema and D. seriema, which composed a polytomic clade in preliminary studies. The analysis of patterns of intraspecific variation revealed two different lineages of period in D. koepferae, probably reflecting introgressive hybridization from D. buzzatii, in concordance with previous molecular data.     

箬竹叶片活性成分含量的季节变化

以2008年于南京地区采集的粽粑竹、美丽箬竹和阔叶箬竹竹叶为试验材料,研究了箬竹叶片中总黄酮、茶多酚和可溶性糖含量的季节变化.结果表明: 3个竹种叶片的总黄酮、茶多酚和可溶性糖含量存在显著的季节差异.不同季节叶片中总黄酮含量为1.7%～2.7%,春季粽粑竹和美丽箬竹叶片中总黄酮含量最高,冬季阔叶箬竹叶片中总黄酮含量最高;茶多酚含量为5.5%～7.6%;可溶性糖含量在1.0%～8.5%,以春季最高.在展叶后3个月内, 粽粑竹和美丽箬竹叶片中各活性成分含量随叶龄的增加而增加.12月至翌年3月为箬竹叶的最佳采叶时期. 3个竹种中,阔叶箬竹叶片的3种活性成分含量均最高,是活性成分利用潜力较大的竹种.     

Accuracy of the StressEraser<Superscript>®</Superscript> in the Detection of Cardiac Rhythms

StressEraser is a commercially marketed biofeedback device designed to enhance heart rate variability. StressEraser makes its internal calculations on beat-to-beat measures of finger pulse intervals. However, the accuracy and precision of StressEraser in quantifying interbeat intervals using finger pulse intervals has not been evaluated against standard laboratory equipment using R-R intervals. Accuracy was assessed by simultaneously recording interbeat intervals using StressEraser and a standard laboratory ECG system. The interbeat intervals were highly correlated between the systems. The average deviation in interbeat interval recordings between the systems was approximately 6 ms. Moreover, correlations approached unity between the systems on estimates of heart period, heart rate, and heart rate variability. Feedback from StressEraser is based on an interbeat time series that provides sufficient information to provide an excellent estimate of the dynamic changes in heart rate and heart rate variability. The slight variations between StressEraser and the laboratory equipment in quantifying heart rate and heart rate variability are due to features related to monitoring heart rate with finger pulse: (1) a lack in precision in the peak of the finger pulse relative to the clearly defined inflection point in the R-wave, and (2) contribution of variations in pulse transit time.     

Effects of high dietary fibre diets formulated from by-products from vegetable and agricultural industries on plasma metabolites in gestating sows

The aim of the present study was to examine the biochemical influence of feeding high dietary fibre (DF) diets formulated from by-products from the vegetable and agricultural industries to sows during early to mid-gestation. The effect of feeding frequency (once vs. twice daily) on diurnal plasma metabolites patterns was also examined. The study included a total of 48 gestating sows from four blocks (12 gestating sows in each block). The sows were fed four different diets containing varying levels of starch (304–519 g/kg dry matter (DM)) and DF (171–404 g/kg DM) but with equal amounts of net energy. The low-DF diet (control) was based on barley and wheat, and the three high-DF diets formulated by replacing barley and wheat by pectin residue, sugar beet pulp and potato pulp, respectively. The experimental design comprised two periods of 4 weeks each. Half the sows were fed once daily at 08:00 h in the first period and twice daily at 08:00 and 15:00 h during the second period, and vice versa for the other half of the sows. Plasma samples from vena jugularis were collected by venipuncture at 07:00, 09:00, 12:00 and 19:00 h. Feeding high-DF increased plasma short-chain fatty acids (p = 0.02) and non-esterified fatty acids (p < 0.001). However, there was no clear effect of DF on glucose and insulin responses. A negative correlation between amount of DF in the diets and plasma creatine (R ² = 1.00; diet effect: p = 0.02) suggested that plasma creatine concentrations was an indicator for the level of glucose–glycogen interchange. Furthermore, an explorative approach using nuclear magnetic resonance spectroscopy-based metabonomics identified betaine (p < 0.001), dimethyl sulfone (DMSO₂; p < 0.001) and scyllo-inositol (p < 0.001) as biomarkers for the different by-products; pectin residue was related to high plasma levels of DMSO₂, sugar beet pulp to plasma betaine, DMSO₂ and scyllo-inositol, and potato pulp to plasma DMSO₂ and scyllo-inositol. In conclusion, replacing starch by DF affected surprisingly few metabolites in peripheral plasma. No negative effects were found in feeding pectin residue, sugar beet pulp or potato pulp for gestating sows as judged from the minor metabolic changes.