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农产品的质量与其生长环境和保存环境密切相关,而农业对象又具有分散偏僻的特点,因此研究便捷、低功耗、精确的远程温湿度监测装置具有现实意义。此装置由传感节点和中继节点组成,传感节点选用NRF24 LE1低功耗器件,负责感知环境的温湿度,通过2.4 GHz无线短距传输上传至中继节点;终端PC利用GPRS远距离与中继节点通信,实时周期性收集中继节点汇聚的传感数据。传感节点与中继节点间采用防碰撞延时发送机制,实现传感节点的低功耗和数据有效传输。中继节点与终端PC通过GPRS网络建立UDP连接,使系统可以管理多个中继节点,可扩展性好。 相似文献
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以牛粪为堆肥原料,研究不同浓度木醋液对牛粪堆肥理化性质的影响。试验采用好氧人工翻堆方式进行。试验共设4个处理,浓度分别为0.2%、0.5%、0.8%的木醋液处理和不添加木醋液的对照处理。通过试验分析温度、含水率、EC、pH值、铵态氮和硝态氮含量等指标随堆肥发酵时间变化的特征。结果表明:各处理组在堆肥发酵过程中pH均在适宜微生物生长的范围内,含水率都保持在55%以上;EC都呈先上升后下降的趋势;添加不同浓度木醋液处理与对照处理相比,都显著提高铵态氮硝态氮含量,从而有效减少堆肥发酵过程中氨气挥发和氮素损失,其中浓度为0.5%木醋液处理效果最好,与对照相比,肥堆升温快,进入高温所需时间短,高温持续时间长,在整个堆肥发酵过程中含水率一直保持在60%~70%之间,发酵结束时物料电导率较低,堆料腐熟快,有利于加快堆肥发酵进程。 相似文献
166.
Shunhua Yang Shangkao Deng Haiou Kuang Danyin Zhou Xueyang Gong Kun Dong 《Journal of insect science (Online)》2021,21(4)
The hexagonal structure of the honey bee comb cell has been the source of many studies attempting to understand its structure and function. In the storage area of the comb, only honey is stored and no brood is reared. We predicted that honey bees may construct different hexagonal cells for brood rearing and honey storage. We used quantitative analyses to evaluate the structure and function of the natural comb cell in the Chinese bee, Apis cerana cerana and the Italian bee, A. mellifera ligustica. We made cell molds using a crystal glue solution and measured the structure and inclination of cells. We found that the comb cells of A. c. cerana had both upward-sloping and downward-sloping cells; while the A. m. ligustica cells all tilted upwards. Interestingly, the cells did not conform to the regular hexagonal prism structure and showed irregular diameter sizes. In both species, comb cells also were differentiated into worker, drone and honey cells, differing in their diameter and depth. This study revealed unique differences in the structure and function of comb cells and showed that honey bees design their cells with precise engineering to increase storage capacity, and to create adequate growing room for their brood. 相似文献
167.
M.‐Y. Qian L. Wei D. Zhou Z.‐J. Zhang J.‐K. He Q.‐J. Zhang P. Zhu X.‐L. Xiao 《Journal of veterinary pharmacology and therapeutics》2016,39(1):84-89
Nanotechnology applications in medicine have seen a tremendous growth in the past decade and are being employed to enhance the stability and bioavailability of lipophilic substances, such as florfenicol. This study aimed to examine the pharmacokinetic properties of the formulated oil‐in‐water florfenicol‐loaded nanoemulsion (FF‐NE). FF‐NE and florfenicol control (Nuflor®) were administered to the pigs at a dose of 20 mg/kg. Nanoemulsion formulation of florfenicol was highly influenced in vivo plasma profile. The in vivo absorption study in pigs indicated that Cmax (14.54 μg/mL) was significantly higher in FF‐NE, 3.42 times higher than the marketed formulation. In comparison with the control group, the relative bioavailability of formulated nanoemulsion was up to 134.5%. Assessment of bioequivalence using log‐transformed data showed that the 90% confidence intervals (90% CI) of Cmax and AUC0–∞ were 2.48–4.60 and 1.21–1.72, respectively. 相似文献
168.
Two single nucleotide polymorphisms in the promoter of the ovine myostatin gene (MSTN) and their effect on growth and carcass muscle traits in New Zealand Romney sheep 下载免费PDF全文
J. Wang H. Zhou J. Hu S. Li Y. Luo J.G.H. Hickford 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2016,133(3):219-226
Myostatin is a negative regulator of muscle growth and development in mammals, and variation in ovine myostatin gene (MSTN) has been demonstrated to be associated with variation in the muscularity of sheep. Polymerase chain reaction–single‐stranded conformational polymorphism (PCR–SSCP) was used to look for single nucleotide polymorphisms (SNPs) in a 304‐bp amplicon from the promoter region of ovine MSTN. Sequence analyses revealed two previously identified SNPs (c.?2449G/C and c. ?2379T/C) that resulted in three haplotypes (H1 (c.[?2449G; ?2379C]), H2 (c.[?2449C; ?2379C]) and H3 (c.[?2449G; ?2379T]). The effect of these SNPs on growth and carcass traits was investigated in 357 NZ Romney lambs. General linear mixed‐effect models revealed that sheep with the genotype c.?2449GC had a higher loin meat yield (p = 0.032) and proportion loin yield (p = 0.028), than those with the genotype c.?2449GG. The genotype c.?2379CC was associated with an increase in three weight traits: birthweight (p = 0.003), tailing weight (p = 0.009) and weaning weight (p = 0.028), when compared with the genotype c.?2379TC, but it was not found to have an association with growth rate. This suggests that c.?2379T/C has an effect that originates at, or before birth. Haplotype H3 was associated with a decrease in birthweight (p = 0.002), tailing weight (p = 0.003) and weaning weight (p = 0.011). Haplotype H2 was associated with increased loin yield (p = 0.012) and proportion loin yield (p = 0.002). The SNPs may have value as genetic markers for improved Romney breeding. 相似文献
169.
通过对淮北市五马路沿线2块夏大豆的田间调查分析表明:受路灯照射的影响,夏大豆株高增加,开花期、成熟期推迟,底荚部位上升,单株生产力下降.且距离越近,植株越高,开花、成熟越晚,底荚部位越高,单株生产力越低. 相似文献
170.
Inhibition of porcine circovirus type 1 and type 2 production in PK-15 cells by small interfering RNAs targeting the Rep gene 总被引:1,自引:0,他引:1
Porcine circovirus type 1 (PCV1) and type 2 (PCV2) are two genotypes of porcine circovirus. Both of them are presumed to be widespread in the swine population. Currently, there is no specific treatment for their infections. RNA interference (RNAi) is a sequence-specific RNA degradation mechanism mediated by small interfering RNA (siRNA), which represents a possible therapeutic application for the treatment of viral infections. In this study, three siRNA expression plasmids (pS-RepA, pS-RepB and pS-RepC) were generated to target three different coding regions of the Rep protein (Rep) of PCV. These siRNAs were used to inhibit PCV production in a porcine kidney cell line, PK-15 cells. Our results revealed that Rep gene expression was inhibited by pS-RepA, pS-RepB and pS-RepC to different degrees. Moreover, our study also showed that the production of PCV1 and PCV2 was reduced by these siRNAs. pS-RepC, which targets the middle region of Rep gene, proved to be the most efficient siRNA for inhibition of Rep expression and viral production. Taken together, our data suggest that RNAi could be investigated as a potential treatment for PCV infection. 相似文献