香港大蹄蝠出飞时间及其季节变化

于2014年5月至2015年4月,对香港低海拔栖息地的大蹄蝠夜晚出飞活动时间进行了研究。结果显示大蹄蝠出飞时间平均为日落后（14.6±6.1) min,出飞时间与民用曙暮光呈强正相关（r = 0.968, P < 0.0001）,而出飞结束时刻同样与民用曙暮光时间呈现显着相关(r = 0. 977, P < 0. 0001)。。在一年中较冷的12月和1月则没有蝙蝠出飞记录。大蹄蝠虽然在亚洲分布广泛,但是相对于温带地区的蝙蝠物种来说, 关于该物种的基础生态学研究较少。本文对大蹄蝠的季节性出飞行为所开展研究工作,以利有关长远保育的深入研究。     

Diffuse knapweed (Centaurea diffusa Lam.) seedling emergence and establishment in a Colorado grassland

Knapweeds (Centaurea spp.) are damaging invaders of grasslands and other North American rangelands. A field study was conducted to determine conditions that promote diffuse knapweed (C. diffusa) emergence and establishment in a native Colorado grassland (North America). Knapweed was planted in native grassland under treatments with different opening sizes, levels of competition, knapweed seed burial and season of seeding. There was no effect of opening size where competing natives were alive, but knapweed emergence in 5- and 15-cm openings was higher than 0-cm openings where natives were killed. Reducing competition reduced fall diffuse knapweed emergence, but did not affect spring emergence. Seed burial increased knapweed emergence, but the effect varied by season. Although diffuse knapweed emergence reached 35%, only four plants survived from 3,600 seeds. This native grassland did not prevent knapweed emergence or establishment, but both were so low that rapid knapweed invasion is unlikely.     

Unusual change in activity pattern at cool temperature in a reptile (Sphenodon punctatus)

Animals that can be active both during day and night offer unique opportunities to identify factors that influence activity pattern. By experimental manipulations of temperatures under constant photoperiod, we aimed to determine if emergence, activity and thermoregulatory behaviour of juvenile tuatara (Sphenodon punctatus) varied at different temperatures (20 °C, 12 °C and 5 °C). To help clarify its activity pattern, we compared tuatara with two lizard species endemic of the South Island of New Zealand for which activity pattern is known and clearly defined: the nocturnal common gecko Woodworthia “Otago/Southland” and the diurnal McCann׳s skink Oligosoma maccanni. Tuatara showed similar responses to both species of lizards. Similar to the diurnal skinks, tuatara emerged quickly at 20 °C and 12 °C while nocturnal geckos took more time to emerge. Like nocturnal geckos, tuatara continued to be active at 5 °C, but only during the day. Interestingly, tuatara shifted from diurno-nocturnal activity at 20 °C and 12 °C to being strictly diurnal at 5 °C. We suggest that this temperature-dependent strategy maximises their survival during cold periods.     

Stable germination behavior but partly changing seed–seed interactions along a steep rainfall gradient

Germination marks a critical transition in plant life that is prone to high mortality. Strong selection pressure is therefore expected to finely tune it to environmental conditions. Our study on the common Mediterranean grass Brachypodium hybridum assessed whether germination behavior changes systematically along a steep natural rainfall gradient ranging from harsh desert to rather mild mesic-Mediterranean conditions. We specifically tested hypotheses that germination behavior confers greater risk-spreading in populations from drier, unpredictable environments, and that seeds from wetter populations are better competitors.In 14 populations (spanning 114–954 mm annual rainfall) we assessed three alternative key parameters of germination in a greenhouse experiment: between-year dormancy, days to emergence within a season, and temporal spread. Addition of neighbor seeds accounted for competition as another crucial environmental factor. In six of the 14 populations, we also compared seeds originating from corresponding north (more mesic) and south (more arid) exposed hill slopes to test whether germination patterns along the large-scale rainfall gradient are paralleled at this smaller scale.B. hybridum exhibited generally high germination fractions and rapid emergence with very little temporal spread, indicating overall little risk-spreading germination. Surprisingly, none of the three parameters changed systematically with increasing aridity, neither at large scale along the rainfall gradient nor at small scale between north and south exposures. Neighbor seeds, however, mildly suppressed germination. Germination of neighbor seeds, in turn, was more strongly suppressed by B. hybridum seeds from drier populations, and this effect was stronger for forb than for grass neighbor species.Our results provide strong evidence that increased risk-spreading germination is not a universal, essential strategy to persist in increasingly dry, unpredictable environments. They also highlight that competition with neighbors occurs even at the earliest plant life stage. Since neighbor effects were species-specific, competition among seeds can affect community composition at later plant stages.     

右美托咪啶对急性主动脉夹层患者谵妄及血清CRP、MMPs、NT-proBNP、NE水平的影响

目的:探讨右美托咪啶对急性主动脉夹层患者谵妄及血清C反应蛋白(CRP)、基质金属蛋白酶(MMPs)、N端前脑钠肽(NT-proBNP)、中性粒细胞弹性蛋白酶(NE)水平的影响。方法:选择2014年1月~2017年1月我院收治的急性主动脉夹层患者84例,根据随机数字表法将其分为对照组(n=42)与研究组(n=42)。对照组入院后给予吗啡镇痛,研究组则给予右美托咪啶镇痛。观察对比两组治疗前与治疗24 h后C反应蛋白(CRP)、基质金属蛋白酶-9(MMP-9)、基质金属蛋白酶-2(MMP-2)、NT-proBNP和NE水平、谵妄的发生率以及脱机持续时间与ICU入住时间。结果:治疗前两组患者CRP、MMP-9、MMP-2、NT-proBNP、NE水平比较无统计学差异(P0.05),治疗24h后研究组CRP、MMP-9、MMP-2、NT-proBNP、NE水平低于对照组与治疗前,差异有统计学意义(P0.05)。研究组术后谵妄的发生率为7.14%(3/42),低于对照组的26.19%(11/42),差异有统计学意义(P0.05)。研究组脱机持续时间与ICU入住时间均低于对照组,差异有统计学意义(P0.05)。结论:右美托咪啶不仅具有镇痛、镇静等效应,还对急性主动脉夹层患者炎性反应具有显著的抑制作用,且降低了谵妄的发生率,保证了患者的预后质量。     

Cold tolerance in tomato. II. Early seedling growth of Lycopersicon spp.

Hypocotyl and root growth elongation of etiolated seedlings was measured non-destructively for the wild tomato accessions LA 460 ( Lycopersicon chilense Dun.), PI 126435, PI 127831 and PI 127832 ( L. peruvianum Mill.) and controls PI 120256 and T3 ( L. esculentum Mill.) on slant boards at 10, 15 and 20°C. Both hypocotyl and root elongation over time were fitted by a logistic growth function with three parameters estimated for each seedling by non-linear least squares regression. Analysis of variance of these equation parameters indicated linear decreases of both hypocotyl and root growth rate parameters with temperature. All four wild accessions maintained greater hypocotyl growth rate parameters at 10°C than the fast-germinating cultivated accession PI 120256, but not significantly greater than T3. Hypocotyl growth rates of the wild accessions were less inhibited at 10°C relative to 20°C than were either cultivated accession. These results suggest that these wild accessions have greater chilling tolerance than cultivated controls for early seedling growth, and may have potential use for genetically improving emergence times for tomatoes sown in cold soil.     

Social behavior of early emerging males of a Japanese paper wasp,Polistes chinensis antennalis (Hymenoptera: Vespidae)

Summary Five cases of the early emergence of males in a Japanese paper wasp,Polistes chinensis antennalis, in which male emerged together with the first group of workers, were described. In one case of the five where the queen disappeared before the emergence of male, worker(s) produced female offspring. The frequency of the nests where the early emergence of male was observed was 16.7% (5/30 nests). In two colonies, worker(s) and/or queen chased off males. But in an orphan nest where worker(s) produced female offspring, the dominance order among workers which was similar to that of colony without male was observed. The significance of the early emergence of male in the social evolution of wasps was discussed.     

Studies on the distribution pattern of the pine needle gall midge,Thecodiplosis japonensis Uchida etInouye (Diptera: Cecidomyiidae) in a pine forest

Numerical changes and distribution patterns of the pine needle gall midge, Thecodiplosis japonensisUchida etInouye , were studied during the period from 1978 to 1979 in a young plantation of Pinus thunbergii in Shiga Prefecture, Japan. The survivorship curve of this species was characterized by a low mortality of larvae in galls and two high mortalities before the formation of galls and during the overwintering period in soil. The within and between-trees distributions of eggs and larvae in galls were examined by using the regression method. The egg distribution per shoot was aggregative both within and between host plants. The within-tree variations in numbers of eggs per shoot were related to the differences in the abundance of available needles for oviposition per shoot among the canopy layers. The between-tree variations reflected the heterogeneous emergence of adult females in the study plot. The degree of aggregation increased from egg to gall stage in both within- and between-tree distributions and the increase was explained by the different mortality of larvae within trees and the inversely density-dependent mortality between trees. The distribution patterns in the soil habitat stages were examined by the patchness index (). This species showed aggregative distributions in soil stages. There was a correlation in spatial patterns of adult emergence between the successive generations. The distribution properties of this species were discussed in connection with the population dynamics and the availability of host plants in the study plot.     

A method for estimating natural survival rate and mean fecundity of an adult insect population by dissecting the female reproductive organs

Several problems were discussed in relation toMacDonald' s method (MacDonald , 1957) for estimating the survival rate of a natural population of adults with varying survival rates and unstable age structure.

1. Random samplings with a fixed sampling ratio and an appropriate census interval is pre-requisite during the occurrence of the adults.
2. At each sampling, female adults are dissected to know the ratio, p_i, of nulliparous females in ith sample (i=0, 1, 2, 3, …,). The Σn_ip_i/Σn_i gives an estimate of the ratio, Fα/F, of nulliparous females in the population where n_i refers to the population size on ith census date. If a constant daily survival rate is assumed, the daily survival rate is estimated from equation (4′). When the survival rate is not constant over the period of adult occurrence, e. g. before and after the initiation of oviposition, the survival rate during pre-ovipositional period is estimated by equation (4″).
3. Decision of an economic census interval to obtain a reliable estimate of the ratio, Fα/F, is depending on the form of emergence curve, particularly on its duration and the length of pre-ovipositional period. If the normal distribution can be assumed for the emergence curve, an interval less than one third of the emergence period is recommended. Concerning with insects having a long pre-ovipositional period, a census interval which exceeds one third of the emergence period still gives a good estimate of Fα/F.
4. The mean realized fecundity of some kind of insects can be estimated by equation (5′ or 5″) using the estimates obtained by the present method.