| 21. |
- Dong, Jianbo, et al.
(författare)
-
Venice: Exploring Server Architectures for Effective Resource Sharing
- 2016
-
Ingår i: Proceedings - International Symposium on High-Performance Computer Architecture. - 1530-0897. - 9781467392112 ; 2016-April, s. 507-518
-
Konferensbidrag (refereegranskat)abstract
- Consolidated server racks are quickly becoming the backbone of IT infrastructure for science, engineering, and business, alike. These servers are still largely built and organized as when they were distributed, individual entities. Given that many fields increasingly rely on analytics of huge datasets, it makes sense to support flexible resource utilization across servers to improve cost-effectiveness and performance. We introduce Venice, a family of data-center server architectures that builds a strong communication substrate as a first-class resource for server chips. Venice provides a diverse set of resource-joining mechanisms that enables user programs to efficiently leverage non-local resources.To better understand the implications of design decisionsabout system support for resource sharing we have constructed a hardware prototype that allows us to more accurately measure end-to-end performance of at-scale applications and to explore tradeoffs among performance, power, and resource-sharing transparency. We present results from our initial studies analyzing these tradeoffs when sharing memory, accelerators, or NICs. We find that it is particularly important to reduce or hide latency, that data-sharing access patterns should match the features of the communication channels employed, and that inter-channel collaboration can be exploited for better performance.
|
|
| 22. |
|
|
| 23. |
- Gao, Xiang, et al.
(författare)
-
Characterization of two β-galactosidases LacZ and WspA1 from Nostoc flagelliforme with focus on the latter’s central active region
- 2021
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 11:1
-
Tidskriftsartikel (refereegranskat)abstract
- The identification and characterization of new β-galactosidases will provide diverse candidate enzymes for use in food processing industry. In this study, two β-galactosidases, Nf-LacZ and WspA1, from the terrestrial cyanobacterium Nostoc flagelliforme were heterologously expressed in Escherichia coli, followed by purification and biochemical characterization. Nf-LacZ was characterized to have an optimum activity at 40 °C and pH 6.5, different from that (45 °C and pH 8.0) of WspA1. Two enzymes had a similar Michaelis constant (Km = 0.5 mmol/liter) against the substrate o-nitrophenyl-β-D-galactopyranoside. Their activities could be inhibited by galactostatin bisulfite, with IC50 values of 0.59 µM for Nf-LacZ and 1.18 µM for WspA1, respectively. Gel filtration analysis suggested that the active form of WspA1 was a dimer, while Nf-LacZ was functional as a larger multimer. WspA1 was further characterized by the truncation test, and its minimum central region was found to be from residues 188 to 301, having both the glycosyl hydrolytic and transgalactosylation activities. Finally, transgenic analysis with the GFP reporter protein found that the N-terminus of WspA1 (35 aa) might play a special role in the export of WspA1 from cells. In summary, this study characterized two cyanobacterial β-galactosidases for potential applications in food industry.
|
|
| 24. |
- Giandomenico, Valeria, et al.
(författare)
-
Olfactory Receptor 51E1 as a Novel Target for Diagnosis in Somatostatin Receptor Negative Lung Carcinoids
- 2013
-
Ingår i: Journal of Molecular Endocrinology. - 0952-5041 .- 1479-6813. ; 51, s. 277-286
-
Tidskriftsartikel (refereegranskat)abstract
- Somatostatin receptors (SSTRs) may be used in lung carcinoids (LCs) for diagnosis and therapy, although additional targets are clearly warranted. This study aimed to investigate whether olfactory receptor 51E1 (OR51E1) may be a potential target for LCs. OR51E1 coding sequence was analyzed in LC cell lines, NCI-H727 and NCI-H720. OR51E1 transcript expression was investigated in LC cell lines and frozen specimens by quantitative real-time PCR. OR51E1, SSTR2, SSTR3, and SSTR5 expression was evaluated by immunohistochemistry on paraffin-embedded sections of 73 typical carcinoids (TCs), 14 atypical carcinoids (ACs) and 11 regional/distant metastases, and compared to OctreoScan data. Immunohistochemistry results were rendered semiquantitatively on a scale from 0 to 3+, taking into account the cellular compartmentalization (membrane vs. cytoplasm) and the percentage of tumor cells (<50% vs. >50%). Our results showed that wild-type OR51E1 transcript was expressed in both LC cell lines. OR51E1 mRNA was expressed in 9/12 TCs and 7/9 ACs (p=NS). Immunohistochemically, OR51E1, SSTR2, SSTR3 and SSTR5 were detected in 85%, 71%, 25% and 39% of TCs, and in 86%, 79%, 43% and 36% of ACs, respectively. OR51E1 immunohistochemical scores were higher or equal compared to SSTRs in 79% of TCs and 86% of ACs. Furthermore, in the LC cases where all SSTR subtypes were lacking, membrane OR51E1 expression was detected in 10/17 TCs and 1/2 ACs. Moreover, higher OR51E1 immunohistochemical scores were detected in 5/6 OctreoScan-negative LC lesions. Therefore, the high expression of OR51E1 in LCs makes it a potential novel diagnostic target in SSTR-negative tumors.
|
|
| 25. |
- Jiang, Pengfei, et al.
(författare)
-
VLBI astrometry on the white dwarf pulsar AR Scorpii
- 2023
-
Ingår i: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 520:2, s. 2942-2951
-
Tidskriftsartikel (refereegranskat)abstract
- AR Scorpii (AR Sco), the only-known radio-pulsing white dwarf binary, shows unusual pulsating emission at the radio, infrared, optical, and ultraviolet bands. To determine its astrometric parameters at the radio band independently, we conducted multi-epoch Very Long Baseline Interferometry (VLBI) phase-referencing observations with the European VLBI Network at 5 GHz and the Chinese VLBI Network plus the Warkworth 30-m telescope (New Zealand) at 8.6 GHz. By using the differential VLBI astrometry, we provide high-precision astrometric measurements on the parallax (pi = 8.52(-0.07)(+0.04) mas) and proper motion (mu(alpha) = 9.48(-0.07)(+0.04) mas yr(-1), mu(delta) = -51.32(-0.38)(+0.22) mas yr (-1)). The new VLBI results agree with the optical Gaia astrometry. Our kinematic analysis reveals that the Galactic space velocities of AR Sco are quite consistent with that of both intermediate polars and polars. Combined with the previous tightest VLBI constraint on the size, our parallax distance suggests that the radio emission of AR Sco should be located within the light cylinder of its white dwarf.
|
|
| 26. |
- Johanneson, Bo, et al.
(författare)
-
Systematic validation of hypothesis-driven candidate genes for cervical cancer in a genome-wide association study
- 2014
-
Ingår i: Carcinogenesis. - : Oxford University Press (OUP). - 0143-3334 .- 1460-2180. ; 35:9, s. 2084-2088
-
Tidskriftsartikel (refereegranskat)abstract
- A large number of genetic associations with cervical cancer have been reported in hypothesis-driven candidate gene studies, but most studies have not included an independent replication or the results have been inconsistent between studies. In order to independently validate these associations, we re-examined 58 candidate gene/regions previously reported to be associated with cervical cancer using the gene-based Adaptive Rank Truncated Product (ARTP) test in a genome-wide association study of 1,034 cervical cancer patients and 3,948 controls from the Swedish population. Of the 58 gene/regions, 8 had a nominal p-value < 0.05 (Tumor necrosis factor [TNF], p = 5.0×10(-4); DEAD (Asp-Glu-Ala-Asp) box helicase 1 [DDX1], p = 2.2×10(-3); Exonuclease 1 [EXO1], p=4.7×10(-3); Excision repair cross-complementing rodent repair deficiency, complementation group 1 [ERCC1], p = 0.020; Transmembrane channel-like 6 and 8 genes [TMC6-TMC8], p = 0.023; Secreted phosphoprotein 1 [SPP1], p= 0.028; v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 2 [ERBB2], p = 0.033 and Chloride channel, voltage-sensitive 7 [CLCN7], p = 0.047). After correction for multiple testing only TNF remained statistically significant (p = 0.028). Two single-nucleotide polymorphisms that are in nearly perfect linkage disequilibrium (LD) (rs2857602 and rs2844484) contributed most to the association with TNF. However, they are not independent from the previously reported associations within the MHC region. The very low number of previously reported associations with cervical cancer that replicate in the Swedish population underscore the need to apply more stringent criteria when reporting associations, including the prerequisite of replicating the association as part of the original study.
|
|
| 27. |
- Kou, Mengyun, et al.
(författare)
-
Metabolic engineering of Corynebacterium glutamicum for efficient production of optically pure (2R,3R)-2,3-butanediol
- 2022
-
Ingår i: Microbial Cell Factories. - : Springer Science and Business Media LLC. - 1475-2859. ; 21:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background: 2,3-butanediol is an important platform compound which has a wide range of applications, involving in medicine, chemical industry, food and other fields. Especially the optically pure (2R,3R)-2,3-butanediol can be employed as an antifreeze agent and as the precursor for producing chiral compounds. However, some (2R,3R)-2,3-butanediol overproducing strains are pathogenic such as Enterobacter cloacae and Klebsiella oxytoca. Results: In this study, a (3R)-acetoin overproducing C. glutamicum strain, CGS9, was engineered to produce optically pure (2R,3R)-2,3-butanediol efficiently. Firstly, the gene bdhA from B. subtilis 168 was integrated into strain CGS9 and its expression level was further enhanced by using a strong promoter Psod and ribosome binding site (RBS) with high translation initiation rate, and the (2R,3R)-2,3-butanediol titer of the resulting strain was increased by 33.9%. Then the transhydrogenase gene udhA from E. coli was expressed to provide more NADH for 2,3-butanediol synthesis, which reduced the accumulation of the main byproduct acetoin by 57.2%. Next, a mutant atpG was integrated into strain CGK3, which increased the glucose consumption rate by 10.5% and the 2,3-butanediol productivity by 10.9% in shake-flask fermentation. Through fermentation engineering, the most promising strain CGK4 produced a titer of 144.9 g/L (2R,3R)-2,3-butanediol with a yield of 0.429 g/g glucose and a productivity of 1.10 g/L/h in fed-batch fermentation. The optical purity of the resulting (2R,3R)-2,3-butanediol surpassed 98%. Conclusions: To the best of our knowledge, this is the highest titer of optically pure (2R,3R)-2,3-butanediol achieved by GRAS strains, and the result has demonstrated that C. glutamicum is a competitive candidate for (2R,3R)-2,3-butanediol production.
|
|
| 28. |
- Li, Guohui, et al.
(författare)
-
Room-Temperature Single-Mode Plasmonic Perovskite Nanolasers with Sub-Picosecond Pulses
- 2024
-
Ingår i: Advanced Functional Materials. - 1616-301X.
-
Tidskriftsartikel (refereegranskat)abstract
- With the explosive growth of communication traffic, increasing the modulation bandwidth of semiconductor lasers has attracted significant attention. However, after rapid progress is achieved, further increasing the modulation bandwidth of semiconductor lasers is hampered by the slow charge-carrier dynamics. Here, a room temperature, single-mode perovskite nanolaser with sub-picosecond pulses, enabled by high Purcell enhancement is reported. This enhancement is achieved via transferring an atomically smooth perovskite nanoplatelet onto the surface of an ultra-smooth SiO2/Ag film. This nanolaser features a low mode volume (V) as low as 0.137 µm3, a high-quality factor (Q) up to 2180, and a low lasing threshold of 36.65 µJ cm−2. The Q value of the laser is one order of magnitude higher than that of state-of-the-art nanolasers. The smoothness of both the nanoplatelet and the SiO2/Ag film in the laser is critical to achieving a high Purcell enhancement. Polarization analysis reveals that the laser emission consists of a transvere-magnetic (TM) polarized surface plasmon mode and a transverse-electric (TE) polarized photonic mode. Furthermore, ultrafast charge-carrier dynamics indicate the surface plasmon decay time can be as short as 0.6 ± 0.4 ps due to the high Purcell enhancement. This work opens up the possibility of developing nanolasers with high bandwidths and ultra-small sizes.
|
|
| 29. |
- Li, Su-Chen, et al.
(författare)
-
The Somatostatin Analogue Octreotide Inhibits Growth of Small Intestine Neuroendocrine Tumour Cells
- 2012
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 7:10, s. e48411-
-
Tidskriftsartikel (refereegranskat)abstract
- Octreotide is a widely used synthetic somatostatin analogue that significantly improves the management of neuroendocrine tumours (NETs). Octreotide acts through somatostatin receptors (SSTRs). However, the molecular mechanisms leading to successful disease control or symptom management, especially when SSTRs levels are low, are largely unknown. We provide novel insights into how octreotide controls NET cells. CNDT2.5 cells were treated from 1 day up to 16 months with octreotide and then were profiled using Affymetrix microarray analysis. Quantitative real-time PCR and western blot analyses were used to validate microarray profiling in silico data. WST-1 cell proliferation assay was applied to evaluate cell growth of CNDT2.5 cells in the presence or absence of 1 μM octreotide at different time points. Moreover, laser capture microdissected tumour cells and paraffin embedded tissue slides from SI-NETs at different stages of disease were used to identify transcriptional and translational expression. Microarrays analyses did not reveal relevant changes in SSTR expression levels. Unexpectedly, six novel genes were found to be upregulated by octreotide: annexin A1 (ANXA1), rho GTPase-activating protein 18 (ARHGAP18), epithelial membrane protein 1 (EMP1), growth/differentiation factor 15 (GDF15), TGF-beta type II receptor (TGFBR2) and tumour necrosis factor (ligand) superfamily member 15 (TNFSF15). Furthermore, these novel genes were expressed in tumour tissues at transcript and protein levels. We suggest that octreotide may use a potential novel framework to exert its beneficial effect as a drug and to convey its action on neuroendocrine cells. Thus, six novel genes may regulate cell growth and differentiation in normal and tumour neuroendocrine cells and have a role in a novel octreotide mechanism system.
|
|
| 30. |
|
|
