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Seagrass plays a vital role in the stability of marine ecology. The human development of marine resources has greatly affected the survival of seagrass. Seawater salinity is one of the important factors affecting its survival. Seagrass can survive in high saline environments for a long time and has evolved a variety of effective tolerance mechanisms. However, little is known about the molecular mechanisms underlying salinity tolerance by seagrass. Thalassia hemprichii is a seagrass species with a global distribution. It is also an ecologically important plant species in coastal waters. Nevertheless, the continuous environmental deterioration has gradually reduced the ecological niche of seagrasses. In this study, experiments were conducted to examine the effects of salinity changes on T. hemprichii. The result showed that the optimal salinity for T. hemprichii is 25 to 35 PSU. Although it can survive under high and low salinity, high mortality rates are common in such environments. Further analyses revealed that high salinity induces growth and developmental retardation in T. hemprichii and further causes yellowing. The parenchyma cells in T. hemprichii also collapse, the structure changes, soluble sugar accumulates rapidly, soluble proteins accumulate rapidly, the malondialdehyde (MDA) content reduces, and lipid peroxidation reduces in plant membranes. The molecular mechanisms of salt tolerance differ significantly between marine and terrestrial plants. We found 319 differentially expressed genes (DEGs). These genes regulate transport and metabolism, promoting environmental adaptation. The expression of these genes changed rapidly upon exposure of T. hemprichii to salinity stress for three hours. This is the first report on the physiological and biochemical changes and gene expression regulation of T. hemprichii under different salinity conditions. The findings of this study well deepen our understanding of T. hemprichii adaptations to changes in the shoal living environment.

In this paper, we conduct systematic measurement studies to show that the high memory bandwidth consumption of modern distributed applications can lead to a significant drop of network throughput and a large increase of tail latency in high-speed RDMA networks.We identify its root cause as the high contention of memory bandwidth between application processes and network processes. This contention leads to frequent packet drops at the NIC of receiving hosts, which triggers the congestion control mechanism of the network and eventually results in network performance degradation. To tackle this problem, we make a key observation that given the distributed storage service, the vast majority of data it receives from the network will be eventually written to high-speed storage media (e.g., SSD) by CPU. As such, we propose to bypass host memory when processing received data to completely circumvent this performance bottleneck. In particular, we design Lamda, a novel receiver cache processing system that consumes a small amount of CPU cache to process received data from the network at line rate. We implement a prototype of Lamda and evaluate its performance extensively in a Clos-based testbed. Results show that for distributed storage applications, Lamda improves network throughput by 4.7% with zero memory bandwidth consumption on storage nodes, and improves network throughput by up 17% and 45% for large block size and small size under the memory bandwidth pressure, respectively. Lamda can also be applied to latency-sensitive HPC applications, which reduces their communication latency by 35.1%.

Background: Sickle seagrass ( Thalassia hemprichii ) is one of the most important marine plants living in the tropical climate, mainly distributed in Southeast Asian waters. It is an important food source for marine herbivores and plays important roles in nitrogen fixation, water purification and maintaining the balance of marine ecology. In recent years, the area of aquatic plants has declined rapidly, affecting the ecological balance. However, the molecular mechanism of aquatic plants has been poorly studied.Results: In this study, all transcriptional information of T. hemprichii was obtained by using high-throughput sequencing technology, and 32,097 unigenes were identified by annotation. In addition, 119 MYB transcription factors were screened, and 61 genes with complete ORF were sequenced. Furthermore, 17 clays were identified according to the information of Arabidopsis .Conclusions: This study provides useful information for enriching the genetic information of T. hemprichii , and further exploring the molecular mechanisms of the evolution, development, and physiological functions of Sickle seagrass.

Geochemical ratios in coral reef skeletons could be used as proxies to reconstruct past climatological and environmental records in data-poor regions. Using a 103-year data set (1902 to 2005), the annual variations in Ba/Ca and Mn/Ca ratios of Porites lutea skeletons at an eastern offshore area of Hainan Island (19°12´28.4´´N, 110°37´38.8´´E) were analyzed using inductively coupled plasma-optic emission spectrometry (ICP-OES). The analysis results showed that Ba/Ca ratios varied from a minimum of 3.120 μmol mol−1 in 1903 to a maximum of 10.064 μmol mol−1 in 1944, with an average of 5.256 μmol mol−1. Mn/Ca ratios varied from 0.206 to 5.708 μmol mol−1 with an annual average of 1.234 μmol mol−1, with peak values in 2001, 1964 and 1932, that correlated with strong rainfall events caused by typhoons. Variation in Ba/Ca and Mn/Ca ratios were compared with available river discharge and precipitation records, providing insight into past climatological events. Human activities and their indirect effects could impact the strength of the relationship between Ba/Ca and Mn/Ca ratios and observed precipitation and terrestrial input in the future.

The room type calorimeter is generally used as the energy efficiency measurement standard equipment in the air conditioner industry. However, the calibration procedure is not investigated. In this study, based on the empty-load situation of calorimeter, the calibration model is proposed in order to restrain the error of heat balance caused by long-term use. Besides, two new parameters, which are background value of indoor-side and outdoor-side, are presented in accordance with the calibration model. Experiments are designed to obtain these two parameters and three heat leakage coefficients of partition wall, as well as the calibration procedure and application method of the parameters are illustrated. The corrected calorimeter measures ten different window type air conditioners in one year. The results show that the absolute value of heat balance is less than 2% in the cooling capacity range of 2000W∼4500W and 1% in the range of 4500W∼7000W.

Complete chloroplast genome of Enhalus acodoides was obtained in this work. Circular mapping revealed that the complete chloroplast sequences of E. acodoides was 176,748 bp in length and had an overall GC content of 38.3%, encoded 132 genes which contained 86 protein-coding genes (PCGs), 38 transfer RNA genes (tRNA) and 8 ribosomal RNA genes (rRNA). The phylogenetic tree shows that E. acodoides had a closer relationship with Thalassia hemprichii in Hydrocharitaceae and its analysis will help better understand the evolution of Alismatales species.

Xisha Islands, located in the northern part of South China Sea, consist of more than 20 islands and atolls. The coral reef of Xisha Islands belongs to the typical ocean distribution of world’s coral reefs, its ecosystem is the most typical in our country and hermatypic coral species are about three-quarters of the total coral species in China. It is addressed with the oldest coral reef community which of the most original and valuable in China. The previous research shows that the islands studded in South China Sea such as Xisha Islands have important influence on the formation of coral reefs along the mainland coast by multiplying and migrating from south to the north. It is supplementary sources of coastal coral larvae in Hainan and Guangdong. Therefore, carrying out the monitoring of coral reef community ecosystem is of great significance to the ecological protection. By the Manta tow and the Line Intercept Transect method, five stations (Xisha Yong xing dao, Shi dao, Xisha zhou, Zhao Shu dao and Bei dao) on Xisha ecological monitoring area were monitored continually from 2005 to 2009. We compared the index changes of Hermatypic coral’s species, coverage and recruitment, and combining with Condition Index, Succession Index, and the variation trend of hard coral in Xisha were analyzed. The results show that, from 2005 to 2009, the coverage of living hermatypic corals in ecological monitoring area is sharply reduced from 68.19% to 7.93%, while the dead coral coverage is sharply increased from 4.70% to 72.90%. Coral recruitment is reduced from 1.18 ind/100 m2 to 0.07 ind/100 m2, hermatypic coral species decreased from 87 to 35. In 2005, the health of coral reefs was very good, and the Condition Index was 1.097. However, the Condition Index cut down to a very low degree in 2009. It was only −0.880. The Succession Index belonged to “very low degree” from 2005 to 2009, and the numerical value was gradually reduce from −0.984 to −1.876. As a whole, hermatypic corals are serious degrade regionally and caused great change to the coral structure and biodiversity, this will lead to a continuous degradation of coral reefs.