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21.
Charles A. Maynard 《In vitro cellular & developmental biology. Plant》1994,30(1):64-69
Summary A field test was established in 1987 to evaluate the growth of micropropagated black cherry plantlets and control seedlings.
The study also evaluated effects of two container types on initial survival and growth and of pruning on stem form and growth.
At the time of field establishment, plantlets had more extensive root systems than the control seedlings. Survival and height
growth were not influenced by container size. Through the first three growing seasons, seedlings were larger than micropropagated
plants, but growth differences diminished in the fourth through sixth seasons. Pruning increased the length of clear stem
by nearly five-fold but adversely affected diameter growth.
Although all clones were from ortet trees more than 50 yr old, none showed plagiotropic growth. Six-year results showed that
in a well-prepared and maintained plantation, black cherry trees derived from tissue culture can have at least 80% survival,
and growth rates in excess of 1 m per year. 相似文献
22.
《Expert review of proteomics》2013,10(4):415-424
In the past decade, analysis of the urinary proteome (urinary proteomics) has intensified in response to the need for novel biomarkers that support early diagnosis of kidney diseases. In particular, this also applies to acute kidney injury, which is a heterogeneous complex syndrome with a still-increasing incidence at the intensive care unit. Unfortunately, this major need remains largely unmet to date. The current report aims to explain why attempts to implement urinary proteomic-discovered acute kidney injury diagnostic candidates in the intensive care unit setting have not yet led to success. Subsequently, some key notes are provided that should enhance the chance of translating selected urinary proteomic candidates to valuable tools for the nephrologist and intensivist in the near future. 相似文献
23.
《Animal : an international journal of animal bioscience》2018,12(10):2181-2190
This study assessed milk productivity, demographic characteristics and workload distribution on a single high-yield dairy ewe farm in Spain (Avila, Spain; continental climate, latitude of 40.90 N, altitude of 900 m) over a 7-year period considering a transition from a herd management system involving five lambings per year (5LY) to a system involving 10 lambings per year (10LY). The 5LY system was practiced on the farm from 2010 to 2012 and the 10LY system from 2014 to 2015, with 2009 and 2013 being considered transition years. During this period, 27 415 lactations were recorded from an average of 3746 Lacaune sheep/year. Several productivity parameters were higher in 2014 to 2015 than in 2010 to 2012: milk yield/lactation (370±156 v. 349±185 l), lactation length (218±75 v. 192±75 days) and dry period length (53.5±38.3 v. 69.1±34.8 days) (all P<0.0001). During 2014 to 2015, investment in new lambing facilities was possible, workload was distributed more uniformly throughout the year, workload per worker was smaller, rate of ewe culling was lower (35.39±0.53% v. 42.51±7.51%), ewe longevity was greater and higher-order lactations were more numerous (P<0.0001). On the other hand, during 2010 to 2012, daily production was higher (1.73±1.66 v. 1.70±0.62 l/day; P=0.038), the interlambing period was shorter (283±50 v. 302±44 days; P<0.0001) and lambings/ewe per year were greater (1.42±0.01 v. 1.30±0.01; P<0.05). These results suggest that a 10LY herd management system can be compatible with profitability, productivity and good animal and worker’s welfare on a high-yield dairy farm, and may even be associated with better outcomes than a 5LY system. 相似文献
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25.
Wild bee diversity is enhanced by experimental removal of timber harvest residue within intensively managed conifer forest 下载免费PDF全文
James W. Rivers Codey L. Mathis Andrew R. Moldenke Matthew G. Betts 《Global Change Biology Bioenergy》2018,10(10):766-781
The use of timber harvest residue as an energy source is thought to have environmental benefits relative to food‐based crops, yet the ecological impact of this practice remains largely unknown. We assessed whether the abundance and diversity of wild bees (Apoidea) were influenced by the removal of harvest residue and associated soil compaction within managed conifer forest in western Oregon, USA. We sampled bees over two years (2014–2015) on study plots that were subjected to five treatments representing gradients in removal of harvest residue and soil compaction. We collected >7,500 bee specimens from 92 distinct species/morphospecies that represented five of the seven bee families. We trapped 3x more individuals in the second year of the study despite identical sampling effort in both years, with most trapped bees classified as ground‐nesting species. Members of the sweat bee family (Halictidae) comprised more than half of all specimens, and the most abundant genus was composed of metallic green bees (Agapostemon, 33.6%), followed by long‐horned bees (Melissodes, 16.5%), sweat bees (Halictus, 15.9%), and bumble bees (Bombus, 13.6%). In both years, abundance and observed species richness were greatest in the most intensive harvest residue treatment, with other treatments having similar values for both measures. Our study indicates that early successional managed conifer forest that has experienced removal of harvest residue can harbor a surprising diversity of wild bees, which are likely to have important contributions to the broader ecological community through the pollination services they provide. 相似文献
26.
目的:探讨强化间歇训练对慢性心衰患者心肺耐力及自主神经功能的影响。方法:34名稳定期慢性心衰患者随机分成试验组和对照组,每组各17名,两组均采用常规药物治疗,其中试验组同时结合间歇运动训练治疗,训练周期12周,前2周为适应性训练,采用功率自行车和30%~50% HRmax强度进行训练,每周训练3次,每次运动20~30 min;后10周采用强化间歇训练,采用功率自行车和运动靶心率=80%~90% HRmax强度训练,训练时间30~40 min,每周训练3次;采用6 min步行距离和心率变异性指标进行效果评价。结果:与试验前比较,12周治疗后,对照组和试验组6 min步行距离均增加,差异具有统计学意义(P<0.01),反映自主神经功能的时域指标和频域指标均出现增高,差异具有统计学意义(P<0.01);试验后,试验组6 min步行距离、时域指标和频域指标改变幅度大于对照组,差异具有统计学意义(P<0.01)。结论:强化间歇训练可以作为慢性心衰患者心肺耐力提高和自主神经功能改善的康复手段,比单一的药物治疗效果更好。 相似文献
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28.
Oxygenation dynamics of sepsis patients undergoing far‐infrared intervention based on near‐infrared spectroscopy 下载免费PDF全文
Kuei‐Hung Chuang Ming‐Lung Chuang Sung‐kien Sia Chia‐Wei Sun 《Journal of biophotonics》2017,10(3):360-366
Near‐infrared spectroscopy (NIRS; continuous wave type) is a noninvasive tool for detecting the relative change of oxyhemoglobin and deoxyhemoglobin. To make this change, intervention methods must be applied. This study determined the hemodynamics of 44 healthy participants and 35 patients with sepsis during exposure to FIR as a novel physical intervention approach. Local microcirculation of their brachioradialis was monitored during exposure and recovery through NIRS. The variations in blood flow and microvascular reaction were determined by conducting paired and unpaired t tests. The oxyhemoglobin levels of the healthy participants increased continuously, even during recovery. In contrast to expextations, the oxyhemoglobin levels of the patients plateaued after only 5 min of FIR illumination. The proposed method has potential applications for ensuring efficient treatment and facilitating doctors in diagnosing the functions of vessels in intensive care units.
29.
Data for the historical years 1970 and 1995 and the FAO-Agriculture Towards 2030 projection are used to calculate N inputs (N fertilizer, animal manure, biological N fixation and atmospheric deposition) and the N export from the field in harvested crops and grass and grass consumption by grazing animals. In most industrialized countries we see a gradual increase of the overall N recovery of the intensive agricultural production systems over the whole 1970-2030 period. In contrast, low N input systems in many developing countries sustained low crop yields for many years but at the cost of soil fertility by depleting soil nutrient pools. In most developing countries the N recovery will increase in the coming decades by increasing efficiencies of N use in both crop and livestock production systems. The surface balance surplus of N is lost from the agricultural system via different pathways, including NH3 volatilization, denitrification, N2O and NO emissions, and nitrate leaching from the root zone. Global NH3-N emissions from fertilizer and animal manure application and stored manure increased from 18 to 34 Tg·yr-1 between 1970 and 1995, and will further increase to 44 Tg·yr-1 in 2030. Similar developments are seen for N2O-N (2.0 Tg·yr-1 in 1970, 2.7 Tg·yr-1 in 1995 and 3.5 Tg·yr-1 in 2030) and NO-N emissions (1.1 Tg·yr-1 in 1970, 1.5Tg·yr-1 in 1995 and 2.0 Tg·yr-1 in 2030). 相似文献
30.
PHILLIP D. JONES SCOTT L. EDWARDS STEPHEN DEMARAIS 《The Journal of wildlife management》2009,73(4):488-496
ABSTRACT Stand establishment techniques involving multiple herbicide applications are commonly used on industrial pine (Pinus spp.) plantations, raising concern over potential effects on white-tailed deer (Odocoileus virginianus) forage production. We tested effects of stand establishment intensity on deer forage in 1–5-year-old loblolly pine (Pinus taeda) plantations (n = 4) in the East Gulf Coastal Plain of Mississippi using forage biomass and 4 measures of nutritional carrying capacity that reflected crude protein or digestible energy requirements for body maintenance and lactation. We also assessed whether forage biomass combined with a deer use rating effectively indexed nutritional carrying capacity. Treatments were combinations of mechanical site preparation, chemical site preparation (CSP), and herbaceous weed control (HWC). Total forage biomass and forage biomass of grasses and forbs were reduced by broadcast HWC. Forage biomass of vines was reduced both by CSP and by multiple broadcast HWC applications. Maintenance-level carrying capacity estimates were reduced by broadcast HWC; lactation-level estimates were higher in moderate-intensity treatments. We believe the inherently low fertility of this region makes high-quality forage production a more important management priority than increasing forage quantity. Chemical or chemical and mechanical site preparation combined with banded HWC provided the best option for providing both forage quality and quantity in open-canopied, intensively managed pine plantations. Biomass-based indices may be suitable for indexing protein-based maintenance-level carrying capacity in this region, but our results indicated they were not useful for indexing other carrying capacity estimates. 相似文献