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The uneven liquid distribution in the shell side of a spiral wound heat exchangers (SWHEs) significantly deteriorates heat transfer in liquefied natural gas (LNG) processes. In this study, an air and water mixture was employed as a substitute for the working fluid to simulate the two-phase flow conditions in practical LNG SWHEs. The experimental investigation focused on the impact of key factors, including gas fraction, flow rate, tube pitch, and layer pitch, on liquid distribution. The findings reveal that the liquid non-uniformity index initially decreases with an increase in gas fraction, reaching an optimal gas fraction of 0.4 for achieving better liquid distribution; the liquid distribution deteriorates at high flow rates under two-phase flow conditions; the liquid distribution improves with a sparser tube pitch under two-phase flow conditions; the liquid distribution deteriorates with a sparser tube pitch at low flow rate under two-phase flow conditions, while the difference diminishes at high flow rate. Recommendations include extending the intermediate vapor quality zone and maintaining lower flow rates for enhanced uniformity in liquid distribution across the shell side. Moreover, appropriately increasing the tube pitch or reducing the layer pitch can further optimize the uniformity of liquid distribution.

Mountain bridges and highways frequently implement shed structures to guard against rolling stone disasters. Due to the random and variable nature of the angle at which stones impact sheds, bedding material is often easily displaced, leading to a wider range of potential damages. In this paper, we analyze the effectiveness of varying grades of shed bedding material when struck by rolling stones at different angles. We also examine the mechanism of the microscopic force chains involved in this process through the use of numerical simulations and physical testing.In this paper, numerical simulation and physical tests are carried out to analyze the shovel scraping effect and plowing effect of rolling stone on bedding layer, the energy dissipation effect of bedding material ，and the internal force chain dispersion transfer law, so as to provide a reference for the design of bedding layer of shanty holes. The results show that: (1) with the increase of impact angle, the impact force of the bedding layer under the same level of proportion increases, but the kinetic energy of the rolling stone is smaller, the fine particle group can reduce the kinetic energy of the rolling stone to the minimum at the earliest time, and the medium particle group can buffer the kinetic energy of the rolling stone to the minimum after the end of the impact process so that we can consider mixing the ratio of the fine particle group and the medium particle group to reach the optimal combination of energy dissipation. (2) 60° for the most unfavorable impact angle, impact angle on the depth of shovel scraping and plowing height of the influence of the trend line fitting formula for y = ax2 + bx + c, which coefficients a, b, c with the particle size; impact angle is larger, the bedding is shovel scraped the smaller the area, but the roof of the hole will be the greater the peak force. (3) Rolling stone initial impact bedding stage, the lower part of the force chain network rapid formation and stress, but the force chain network then quickly extends to the front end, the stress value becomes smaller; the smaller the particle size of the bedding layer, and the larger the coordination number, that is, the better the degree of contact, the larger the particle size of the bedding layer shoveling effect is not obvious, and the force chain is more solid and not easy to rupture.

Stable boundary layer height (SBLH) is an important parameter to characterize the characteristics and vertical structure of the nocturnal lower atmosphere at night. The distribution of SBLH has obvious spatial and temporal differences, and there are many meteorological factors affecting the SBLH, but at present, there are few quantitative studies on the effects of near-surface meteorological factors on the SBLH in the desert hinterland. This study was based on GPS sounding balloon data, near-surface meteorological observation data, and ERA5 data from Tazhong Station (TZ) in the Taklamakan Desert (TD) collected in July 2017, 2019, and 2021. The variation characteristics of the SBLH and its relationship with near-surface meteorological factors are described. We quantitatively analyzed the degree of influence of near-surface meteorological factors affecting the SBLH and verified it using a model. The study also elucidates the possible formation mechanism of the SBLH in the TD hinterland. The SBLH in the TD hinterland trended upward in July 2017, 2019, and 2021, which is consistent with the changes in meteorological factors, according to the near-surface meteorological observation and ERA5 data. Therefore, we think that an inherent connection exists between near-surface meteorological factors and the SBLH. The results of correlation analysis show that complex internal connections and interactions exist among the meteorological factors near the ground; some thermal, dynamic, and other meteorological factors strongly correlate with the SBLH. Having established the change in SBLH (ΔSBLH) and in major thermal, dynamic, and other meteorological factors (Δ), the linear regression equation between them revealed that near-surface meteorological factors can affect the SBLH. The dynamic factors have a stronger influence on the ΔSBLH than thermal and other factors. The results of model validation based on the variable importance projection (VIP) also confirmed that the SBLH in the TD hinterland is jointly affected by dynamic and thermal factors, but the dynamic factors have a stronger impact. The mechanism through which the SBLH forms is relatively complex. At night, surface radiative cooling promotes the formation of a surface inversion layer, and low-level jets strengthen wind shear, reducing atmospheric stability. The combined effects of heat and dynamics play an important role in dynamically shaping the SBLH. This study helps us with accurately predicting and understanding the characteristics of the changes in and the factors influencing the SBLH in the TD hinterland, providing a reference for understanding the mechanism through which the SBLH forms in this area. At the same time, it provides a scientific basis for regional weather and climate simulation, meteorological disaster defense, air quality forecasting, and model parameterization improvement.

Pathogen infection has been progressively recognized as a potential driver of animal migration, and the infection pattern in a certain host may be related to its migration status. Nestling viability can be a crucial life stage in the evolution of the migration cycle but have been irregularly studied to date. In this study, we tested the ‘migratory exposure' hypothesis by comparing the prevalence and diversity of avian haemosporidian parasites in the breeding area between two dominant species including adults and nestlings: yellow‐rumped flycatcher Ficedula zanthopygia, which is a summer migratory species, and Japanese tit Parus minor, which is a local resident species. The yellow‐rumped flycatcher harboured more diverse parasite lineages than the Japanese tit, which is in line with the expectation of the ‘migratory exposure' hypothesis, while nestlings present a similar but more applicable pattern. Among the 40 unique identified parasite lineages, only one was shared between host species and three between age classes. Nestlings suffered a high parasite diversity with plenty of age‐specific lineages in the breeding area, mainly Leucocytozoon, which may suggest an extraordinary selection pressure in early life‐stages during migration. However, the most common lineages in adults were not detected in nestlings, and the prevalence of infection is significantly lower in nestlings than in adults. Our results suggest that migratory birds may have suffered from more frequent parasite infections during migration, but escaped from more virulent lineages at the same time. The difference in susceptibility and parasite assembly between adults and nestlings in migrants may result from an intricate interaction along the evolution of life history. Our investigations have revealed the significance of avian haemosporidian parasite infection patterns in nestlings in breeding areas, and provide a novel insight into the driving forces of migration.

The diversity of waterbirds is threatened, and haemosporidian parasite infection is considered one of the most important causative factors. However, to date, only a few studies focusing on specific parasite species have been carried out, which cannot reflect the general patterns at the community level. To test whether the reported haemosporidian diversity in waterbirds is underestimated, we estimated the prevalence and lineage diversity of avian haemosporidian parasites in 353 waterbirds from 26 species in the Tumuji National Nature Reserve, Northeast China, as well as the host-parasite associations. According to the molecular analysis of cytochrome b (cyt b) barcode sequences, 28.3% of the birds were infected by 49 distinct parasite lineages, including 11 Plasmodium, 12 Haemoproteus, and 26 Leucocytozoon lineages, of which 39 were novel. The highest prevalence was contributed by Leucocytozoon (13.31%), followed by Plasmodium (13.03%) and Haemoproteus (4.25%), which suggested that waterbirds were infected to a lesser extent by Haemoproteus than by the other two genera. Among the most sampled birds, species belonging to Anatidae appeared to be susceptible to Leucocytozoon but resistant to Plasmodium, while Rallidae presented the opposite pattern. On the phylogenetic tree, most of the Leucocytozoon lineages detected in Anatidae clustered together and formed two well-supported clades, while lineages restricted to Gruidae were distantly related to other parasites in all three genera. SW5 was the most abundant lineage and therefore might be a major threat to waterbirds; among the hosts, the common coot harboured the highest diversity of parasite lineages and thus could act as a reservoir for potential transmission. This is the first study of avian haemosporidian infections in a wild waterbird community in Asia. Our findings have doubled the number of lineages recorded in waterbirds, broadened our understanding of host-parasite associations, and addressed the importance of studying haemosporidian infections in wild waterbird conservation.

Migratory birds spend several months in their breeding grounds in sympatry with local resident birds and relatively shorter periods of time at stopover sites. During migration, parasites may be transmitted between migratory and resident birds. However, to what extent they share these parasites remains unclear. In this study, we compared the assemblages of haemosporidian parasites in migratory, resident, and passing birds, as well as the correlations between parasite assemblages and host phylogeny. Compared with passing birds, migratory birds were more likely to share parasites with resident birds. Shared lineages showed significantly higher prevalence rates than other lineages, indicating that common parasites are more likely to spill over from the current host to other birds. For shared lineages, the prevalence was significantly higher in resident birds than in migratory birds, suggesting that migratory birds pick up parasites at their breeding ground. Among the shared lineages, almost two-thirds presented no phylogenetic signal in their prevalence, indicating that parasite transmission among host species is weakly or not correlated with host phylogeny. Moreover, similarities between parasite assemblages are not correlated with either migration status or the phylogeny of hosts. Our results show that the prevalence, rather than host phylogeny, plays a central role in parasite transmission between migratory and resident birds in breeding grounds.

As a research hotspot, circular RNAs (circRNAs) is one type of non-coding RNAs which have many different functions in biological processes. However, there is lack of study investigating the underlying molecular mechanism and the potential roles of circRNAs in Wilms tumor. We conducted a high-throughput microarray sequencing to screen differentially expressed circRNAs in Wilms tumor. A novel circRNA (circ0093740) was identified as a frequently upregulated circRNA in Wilms tumor cells and tissues. Suppression of circ0093740 remarkably inhibited the proliferation and migration ability in Wilms tumor, validated by several experiments. The molecular mechanism of circ0093740 was investigated by luciferase assays and RNA immunoprecipitation assays. The results revealed that circ0093740 promotes the growth and migration ability by sponging miR-136/145 and upregulating DNMT3A. In conclusion, our study discovered the biological role of the circ0093740-miR-136/145-DNMT3A axis in Wilms tumor growth and metastasis which is important for developing new treatment strategy.

Proteins assemble to form frictional complexes is fundamental to efforts in chemistry, structural biology biochemistry, and biophysics. Derived from exons 20, 21, 23, 24, of human elastic, the elastic peptide)(EP) series of proteins are known to coacervate, forming fibrillar aggregates with the high degree of beta-structure and it is believed that overall protein hydropathy and the arrangement of hydropholic domains underpin the self- assembly of these proteins.

A 3D inorganic-organic hybrid proton conductor, [Sm(H2O)5(CO2CH2NH3)2][Al(OH)6Mo6O18]·10H2O (1), has been synthesized by using coordination cations, [Sm(H2O)5(gly)2]3+ (gly = -CO2CH2NH3 +), and polyanions, [Al(OH)6Mo6O18]3- ([AlMo6]). The polyanions ([AlMo6]) and the coordination cations ([Sm(H2O)5(gly)2]3+) stack to form a 3D supramolecular network structure containing 1D channels along the c axis by electrostatic force and H-bonding. Significantly, the 1D channels are water-filled with a high water content (both Sm coordinated and in lattice). Dynamic adsorption measurements were implemented at 1 atm, and 95% relative humidity (RH). The water adsorption amount (6.51 wt% at 25 °C and 5.68 wt% at 80 °C) consistent with the number of lattice water molecules of 1 suggests that the water chains were retained at elevated temperatures (80 °C) under 95% RH. Alternating-current (AC) impedance measurements of 1 reveal an outstanding conductivity for 1 of 4.53 × 10-3 S cm-1 at 80 °C under 95% RH. The activation energy of 1 calculated from the Arrhenius plots of the proton conductivity is 1.09 eV, which indicated that the protons transfer by a vehicle mechanism. [ABSTRACT FROM AUTHOR]

Highly sensitive electrochemical electrodes for glucose detection were developed by using Au nanoclusters (NCs) to modify nitrogen-doped diamond-like carbon thin films (DLC:N/Au). The DLC:N/Au electrodes were prepared with a filtered cathodic vacuum arc process followed by electrodeposition and characterized by X-ray photoelectron spectroscopy, Raman spectroscopy, and scanning electron microscopy. The size of the Au NCs covered by Au oxide ranged between 10 and 70 nm with a density of 108-109 clusters per cm2. Glucose oxidation at the DLC:N/Au electrodes started from about -0.5 V due to the high catalytic activities of the Au NCs in NaOH solutions, and the catalytic ability of the electrodes depended on the amount of Au NCs deposited on the electrode surfaces. A linear detection range of glucose with the DLC:N/Au electrodes was identified from about 0.25 to 30 mM (covering blood glucose levels in diabetic patients) with a detection limit of 60 μM. The experimental results showed that the non-enzymatic glucose sensors based on the DLC:N/Au electrodes had high sensitivity and good reproducibility and stability. [ABSTRACT FROM AUTHOR]

Controlling how molecules assemble into complex supramolecular architectures requires careful consideration of the subtle inter- and intra-molecular interactions that control their association. This is particularly crucial in the context of assembly at interfaces, where both surface chemistry and structure can play a role in directing structure formation. We report here the results of a study into the self-assembly of the elastin-like peptide EP I on structurally modified highly ordered pyrolytic graphite, including the role of spatial confinement on fibril nucleation and the growth of oriented fibril multilayers. In situ atomic force microscopy performed in fluid and at elevated temperature provided direct evidence of frustrated fibril nuclei and oriented growth of independent fibril domains. These results portend the application of this in situ strategy for studies of the nucleation and growth mechanisms of other fibril- and amyloid-forming proteins. [ABSTRACT FROM AUTHOR]

Huntington disease is a genetic neurodegenerative disorder that arises from an expanded polyglutamine region in theNterminus of the HD gene product, huntingtin. Protein inclusions comprised of N-terminal fragments of mutant huntingtin are a characteristic feature of disease, though are likely to play a protective role rather than a causative one in neurodegeneration. Soluble oligomeric assemblies of huntingtin formed early in the aggregation process are candidate toxic species in HD. In the present study, we established an in vitro system to generate recombinant huntingtin in mammalian cells. Using both denaturing and native gel analysis, we have identified novel oligomeric forms of mammalian-derived expanded huntingtin exon-1 N-terminal fragment. These species are transient and were not previously detected using bacterially expressed exon-1 protein. Importantly, these species are recognized by 3B5H10, an antibody that recognizes a two-stranded hairpin conformation of expanded polyglutamine believed to be associated with a toxic form of huntingtin. Interestingly, comparable oligomeric species were not observed for expanded huntingtin shortstop, a 117-amino acid fragment of huntingtin shown previously in mammalian cell lines and transgenic mice, and here in primary cortical neurons, to be non-toxic. Further, we demonstrate that expanded huntingtin shortstop has a reduced ability to form amyloid-like fibrils characteristic of the aggregation pathway for toxic expanded polyglutamine proteins. Taken together, these data provide a possible candidate toxic species in HD. In addition, these studies demonstrate the fundamental differ in early aggregation events between mutant huntingtin exon-1 and shortstop proteins that may underlie the differences in toxicity. [ABSTRACT FROM AUTHOR]