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BackgroundTo characterize the pattern of hospitalization in patients with Alzheimer's disease (AD) or Parkinson's disease (PD), and compare the differences to see whether AD patients and PD patients have a different picture of hospitalization.MethodsThe clinical features of all consecutive patients from January 2017 to December 2020 were reviewed. We identified AD patients and PD patients from an electronic database in a tertiary medical center.ResultsThe study group comprised 995 AD patients and 2,298 PD patients who were admitted to the hospital for the first time, and re-hospitalized 231 AD patients and 371 PD patients were also included. AD patients were older than PD patients when they were hospitalized (p < 0.001). AD patients had longer lengths of stay, higher re-hospitalization rates, and higher intrahospital mortality rates than PD patients during hospitalization even after adjusting age and gender. PD patients had higher levels of total cost than AD patients due to the cost of the deep brain stimulation (DBS) insertion. Hospitalizations for AD patients occurred most often in the department of geriatrics, while most PD patients were admitted to the department of neurology. Hospitalization due to the presence of comorbid conditions was much higher in AD patients, but a larger proportion of PD patients were hospitalized due to PD disease itself.ConclusionsThe present study found that AD patients and PD patients have a significantly different picture of hospitalization. It is important to implement different management for hospitalized AD and PD, and different emphasis should be given when establishing primary prevention strategies, informing care needs, and guiding healthcare resource planning.

Additional file 1: Table S1. Demographic data for the enrolled cohorts. Table S2. In-silico pathogenicity predictions for rare variants in SPTLC1 and SPTLC2. Table S3. Enrichment analysis of rare variants in SPTLC1 and SPTLC2 in amyotrophic lateral sclerosis.

Based on high sensitivity, specific fingerprinting spectra and real-time detection, surface-enhanced Raman spectroscopy (SERS) is a powerful tool for the observation, the detection and the identification of chemical or biological species at low concentrations. One of the key elements for the SERS detection is the choice of SERS substrate. This latter one can be either a home-made one or either commercially purchased. For researchers who don’t have facilities to fabricate SERS substrates, the commercial ones are a necessary and optimal choice. Thus, a comprehensive evaluation of their reproducibility is urgently needed and carried out in this paper. The blank spectra as well as the SERS spectra of three probes molecules (4-mercaptobenzoic acid (4-MBA), 1, 2-bis (4-pyridyl) ethylene (BPE) and methylene blue (MB)) were analysed for two excitation wavelengths (532 and 785 nm). The most suitable detection condition was determined for each substrate. Under the optimum conditions, the SERS mapping were carried to measure the relative standard deviations (RSDs) to further evaluate the reproducibility of the substrates. The results demonstrated that the Enspectrc, Q-SERSTM and Hamamatsu substrates were the more suitable for reproducible SERS measurements.

Deoxyribonucleic acid (DNA) detection is essential for the accurate and early diagnosis of a disease. In this study, a femtomolar DNA detection method based on the exploitation of the localized surface plasmon (LSP) resonance of gold nanoparticles (AuNPs) was developed. We prepared Poly Ethylen Glycol (PEG) functionalized AuNPs with a specific DNA capture probe (CP) directly modified on the gold surface. Two strategies are proposed using different kinds of CP to detect the target DNA (tDNA). In the first strategy, CP is the complementary of the complete sequence of the DNA (CCP method). For the second strategy, we used two CPs, which were half complementary to tDNA, and these were hybridized with tDNA to form sandwich structures (MIX method). The results showed that our detection methods are highly sensitive and that the limits of detection of 124 am and 2.54 fm tDNA can be reached when using the CCP and MIX methods, respectively. In addition, the specificity of our two strategies is also demonstrated with mismatched DNAs. The proposed method provides a simple, fast, sensitive and specific DNA biosensor, which has the potential to be used for point-of-care tests (POCT).

Capture, storage and utilization of CO2 gas through the hydrate technology is deemed as a promising approach to solve the problem on global warming. After efficient transportation of CO2 gas with the self-preservation effect of hydrate, the dissociations of hydrate are required in some practical scenarios. In order to investigate the initial dissociation properties of hydrates while the self-preservation effect was removed, CO2 hydrates were formed in different experimental conditions and media and then frozen. After that, the self-preservation effect of hydrates was slowly removed through a uniform heating method. The measurement results exhibit that comparing with the pure water (PW), the initial dissociation temperatures (IDT) are significantly lowered by the silica gel powder (SG) and sodium dodecyl sulphate (SDS) solution (SS). Similarly, the initial dissociation rates (IDR) of hydrates are also reduced. These patterns are opposite to the traditional elucidating mechanism of the self-preservation effect of hydrate. Hence, the theory of ice shell was supplemented furthermore. In addition, it is found that the final duration time of the entire dissociation process of hydrate after losing the preservation effect presents obvious dependence on the initial dissociation rate (IDR). These findings are expected to provide some references for the future transportation of CO2 gas with the self-preservation effect of hydrate.

Facing complicated hydrate formation processes and dozens of models’ establishments with an attempt to unravel the hidden mechanisms, many parameters have been considered from lots of viewpoints affecting specific hydrate growth process. It appears that incorporating various models into a unique uniform one to account for all formation behaviours seems impossible. Another line of thought is then investigated, i.e. if skipping over complicated specific growth process, whether there is some direct relation between initial nucleation and finally-formed bulk hydrate crystals. Within an experimental apparatus with specially designed structures, one-sided cooling method only from top was used to drag hydrate crystal structures growing upwards from gas-liquid interface. Complete formation processes from initial gas dissolution to final growth termination were then observed through video cameras. It is found that like pea seedlings growth pattern, finally formed bulk crystal structures are in fact propagated from a few initial hydrate embryos and there are significant linear relations between initial nucleation dynamics and final hydration numbers. Some special positions of equipment possess obvious superiority to induce hydrate embryos occurrence, e.g. the four corners of reactor, among which the two adjacent to this reactor wall with more rapid heat conduction are facilitated. The trend lines directions of linear relations are completely opposite, meaning that mechanisms dominating specific growth processes of hydrate crystals are actually disparate under different methods. Final formation reaction efficiency can be achieved by increasing initial nucleation dynamics substantially. Some instructive suggestions on practical applications related with hydrates, e.g. industrial process design, prediction to blocking position owing to hydrates, hydrate formation inhibition by means of physical method etc., may be proposed through these summarized conclusions.

Flowering is essential for fruit production. The effects of nitrogen (N) on flower bud differentiation and early harvest in strawberry are not clear. Experiments were conducted to investigate the most effective concentration of N treatment during the seedling stage and further elucidate the mechanism of flower bud differentiation in cultivated strawberry (Fragaria ananassa Duch.‘Benihoppe’). The results demonstrated that T2 (treatment 2) of 0.1 g/plant was the suitable concentration for flower bud differentiation in strawberry seedlings and then fruit early ripening. Further studies showed that the period of flower bud differentiation happened between August 19 and August 24. The total carbon (C) contents of all treatments except T3 displayed an increasing trend in seedlings before August 14. The C/N ratio (21.45–53.44) increased at the stage of flower bud differentiation in each treatment, which was promoted by an appropriate C/N ratio. Relatively higher ABA and CTKs levels but relatively lower GAs and IAA levels required during flower bud differentiation were detected. Further analysis of ABA/IAA ratio (0.53–0.76) suggested that it was also close to the flower bud differentiation in strawberry. N levels increased at phenological phases of each treatment. Different N levels during the seedling stage had little effect on fruit quality. It also exhibited the highest early harvest (183.0 g/plant) as well as the highest yield (380.3 g/plant) with T2. We found that a relatively high C/N ratio and an appropriate ABA/IAA positively initiate the flower bud differentiation, which suggested that ABA may play an important role in promoting flower bud differentiation in strawberry.

New technologies and advanced methods are the important basis for continuous development of laboratory medicine. Although the labeling analysis has become an important research method in laboratory medicine, label-free methods showed unique advantages, such as high sensitivity, small working volumes, low damage to analytes and easy on-chip integrations. Label-free methods are mainly based on the molecular biophysical properties without conjugated labels, which can largely avoid false positives and can provide more reliable and reproducible detection results. Nowadays, New-generation label-free technologies such as terahertz spectroscopy, Raman spectroscopy, Biochip/Microarray, mass spectrometer, have already shown great potential in biomedical applications, such as the identification of clinical microorganism, rapid and unlabeled detection of bimolecular, and dynamic monitoring of bimolecular interaction and the imaging of the construction and spatial structures. In this review, we summarized recent findings on the development and potential applications of the new-generation label-free technologies in clinical laboratory, focusing on the advantages and biomedical research of terahertz spectroscopy, Raman spectroscopy, Biochip/Microarray, quartz crystal microbalance devices and mass spectrometer. Keywords: Label-free technologies, Terahertz radiation, Raman spectroscopy, Biochip/Microarray, Mass spectrometer

Block designs have been widely used in almost all areas of human investigations. It is commonly assumed that all blocks have the same size which may not, however, always be available because of practical restrictions. In this paper, the problem of main-effect plans with blocks of unequal sizes is addressed. The sufficient condition for each pair of factors to be orthogonal through the block factor is indicated. Useful properties on ANOVA (analysis of variance) of such designs are discussed. Construction procedures via augmenting new blocks and combining main-effect plans with unequal block sizes are also provided. The resulting designs have flexible sizes of blocks and factors.

An indirect aptamer-based SERS assay for insulin-like growth factor 2 receptor (IGF-IIR) protein was developed. The gold substrate and silver nanoparticles (AgNPs) were employed simultaneously to achieve double enhancement for SERS signals. Firstly, the five commercial SERS substrates including Enspectr, Ocean-Au, Ocean-AG, Ocean-SP and Q-SERS substrates were evaluated using 4-mercaptobenzoic acid (4-MBA). The Q-SERS substrate was selected based on low relative standard deviation (RSD, 8.6%) and high enhancement factor (EF, 8.7*105), using a 785 nm laser. The aptamer for IGF-IIR protein was designed to include two sequences: one grafted on gold substrate to specifically capture the IGF-IIR protein and a second one forming a 3′ sticky bridge to capture SERS nanotags. The SERS nanotag was composed by AgNPs (20 nm), 4-MBA and DNA probes that can hybridize with the aptamer. Due to the steric-hindrance effect, when the aptamer doesn’t combine with IGF-IIR protein, it only can capture the SERS nanotags. Therefore, there was a negative correlation between the concentration of IGF-IIR protein and the intensity of 4-MBA at 1076 cm−1. The detection limit reached to 141.2 fM and linear range was from 10 pM to 1 μM. The SERS aptasensor also exhibits a high reproducibility with an average RSD of 4.5%. The interference test was conducted with other four proteins to verify the accuracy of measuring. The study provides an approach to quantitative determination of proteins based on specific recognition and nucleic acid hybridization of aptamers, to establish sandwich structure for SERS enhancement.

To investigate formation and dissociation behaviors of hydrate under non uniform temperature fields and mechanisms behind, methane hydrate was formed and then dissociated within a porous medium in a reactor with fixed positive and reverse temperature gradients. Results show that owing to the water migration under temperate gradients, hydrate concentrates inside the regions at lower temperature. Under temperature gradients, hydrate distribution heterogeneity appears inside the medium during formations. During dissociation under reverse gradient, the upper half part of medium is at higher temperature. Hence, this part is easy to dehydrate with flow up from bottom to top of gas released from dissociation, resulting in emergence of significant medium deformation phenomenon. Under these non uniform temperature fields, hydrate dissociation is primarily controlled by heat transfer. Hydrate distribution heterogeneity directly relates to the water migration under temperature gradients during formation, and the medium deformations along with water discharge during dissociation. Owing to these replicated water migration and dehydration processes under reverse gradient, final hydrate saturation is gradually enhanced accompanying with the increase in formation/dissociation cycle times; on the contrary, is lowered under the positive one. These findings may provide some implications for future methane storage at industrial scale with hydrate technology, and the practical exploitations of natural gas hydrates in nature.

This study introduced the function of BABA in regulating tobacco on alkaline stress and attempted to explore the mechanism through antioxidant system, iontransport and related genes expression. Results showed that both 0.2mmol/L and 0.5mmol/L BABA could significantly increase root length and fresh weight of tobacco under alkaline stress. BABA could increase contents of GSH, ASA, chlorophyll, carotenoid and activities of SOD, APX, POD and CAT while decrease contents of H2O2, proline, MDA and relatively conductivity rate. Decreasing Na+ content and increasing K+ content were to defense ion toxicity and increasing organic acid content could defend high pH toxicity under BABA treatment. Result of real-time relative quantitative PCR showed that BABA could induce NtCaM and ABC translocator genes up-regulated expression to regulate transport and signal transduction and it also induced GSH1and PROX1 genes up-regulated expression to promote the GSH synthesis and proline metabolism. The above evidences suggested that BABA-induced resistance to alkaline stress in tobacco resulted from integrated effect of antioxidant, organic acid synthesis, ion transport and gene expression.

A ternary CaMgFe-LDH was developed for the immobilization of aqueous arsenic from capillary water in paddy soils, with an outstanding removal performance for aqueous arsenite (As(III)). In an As(III) solution, the ternary LDH achieved a removal capacity for arsenite of approximately 16 mg g−1 after 5 h, with a low equilibrium concentration of As(III) (0.048 mg L−1). The As(III) removal capacity of LDH was studied with the different Ca/Mg molar ratios in LDH, which demonstrated that ternary LDHs with a higher Ca content can remove As(III) more effectively and rapidly. Accordingly, the ternary LDH material was used in the immobilization of total arsenic from a paddy soil system, achieving a removal efficiency for As(III) of 47% and a total As concentration of 346 μg L−1 in capillary water after 40 days. Compared to that of the binary Mg–Fe LDH, the As removal performance of the ternary LDH was higher, which was attributed to the As precipitation with Ca in the first 20 days during the experiment. This, along with the efficient adsorption of As on the residual Mg–Fe-LDH framework, was responsible for the low concentration of As. Therefore, our study proposes a promising approach to the remediation of arsenic-contaminated paddy soils.

Terahertz (THz = 1012 Hz) spectroscopy has shown great potential in biomedical research due to its unique features, such as the non-invasive and label-free identification of living cells and medical imaging. In this review, we summarized the advantages and progresses achieved in THz spectroscopy technology for blood cell detection, cancer cell characterization, bacterial identification and biological tissue discrimination, further introducing THz imaging systems and its progress in tissue imaging. We also highlighted the biological effects of THz radiation during its biological applications and the existing challenges and strategies to accelerate future clinical applications. The future prospects for THz spectroscopy will focus on developing rapid, label-free, and convenient biosensors for point-of-care tests and THz in vivo imaging.

A large amount of methane gas released during the service of a landfill will not only cause the greenhouse effect, but it may also cause an explosion when the methane reaches a certain concentration in the air or soil. In the background of promoting energy conservation and environmental protection, it is of great significance to effectively reduce the methane release content in landfills, ensure the normal service of landfill and the safety of people’s life and property. The mechanism of methane oxidation by methane oxidizing bacteria is reviewed and the factors affecting the efficiency of methane oxidizing bacteria to oxidize methane are analyzed in order to reduce the emission reduction of hazardous gases in the landfill and provide a reference for the design of other new landfills.

The concentration of gas has been confirmed as a key factor dominating hydrate nucleation. In this study, CO2 hydrates were formed in pure water and a sodium dodecyl sulphate (SDS) solution using a temperature reduction method under constant pressure at different temperatures. The dissolving properties of CO2 throughout the whole induction period were investigated in detail. The experimental results showed that the ‘memory effect’ of hydrate might not be attributed to residual water structures after hydrate dissociation. Instead, residual gas molecules in the aqueous phase should receive more attention. Hydrate nucleation was confirmed to be a type of chain reaction. Low temperature was a significant factor that promoted hydrate nucleation. As a result, these two factors enhanced the stochastic features of the CO2 hydrate nucleation reaction. Even under the same conditions, critical gas concentrations beyond the threshold that hydrates can spontaneously nucleate were not fixed, but they still exhibited linear relations regarding a set temperature. Taking the significant influences of temperature into account, a new nucleation mechanism for CO2 hydrates was established based on the potential of the reaction system. Therefore, this study sheds new light when explaining the reason for the formation of gas hydrates in natural reservoirs.

Bt crops that are transgenic crops engineered to produce Bt toxins which occur naturally with Bacillus thuringiensis (Bt) have been widely planted and its environmental risk assessment has been heavily debated. The effects of Bt crops on soil microbial communities are possible through changing the quantity and quality of C inputs and potential toxic activity of Bt protein on soil organisms. To date, the direct effects of Bt protein on soil microorganisms is unclear. Here we added Cry1Ac, one of the most commonly used Bt protein in Bt crops, to the soil and monitored changes in soil bacterial, fungal and archaeal diversities and community structures using ribosomal DNA-fingerprinting method, as well as their population sizes by real-time PCR over a 100-day period. Despite the fact that variations were observed in the indices of evenness, diversity and population sizes of bacteria, fungi and archaea with different Cry1Ac addition rates up to 100ngg-1 soil, the indices of soil microbial diversities and evennesses did not significantly shift with Cry1Ac protein addition, nor did population sizes change over time. The diversities of the dominant bacteria, fungi and archaea were not significantly changed, given Cry1Ac protein addition rates over a period of 100 days. These results suggested that Bt protein derived by cultivations of transgenic Bt crops is unlikely to cause transient or even persisting significant changes in soil microorganisms in field.

Sub-micron sized LiNi0.8Co0.15Al0.05O2 cathode materials with improved electrochemical performance caused by the reduced cationic disordering in Li slab were synthesized through a solid state reaction routine. In a typical process, spherical precursor powder was prepared by spray drying of a uniform suspension obtained from the ball-milling of the mixture of the starting raw materials. Then the precursor powders were pressed into tablets under different pressures and crushed into powder. The pressing treated powders were finally calcinated under oxygen atmosphere to obtain the target cathode materials. XRD investigation revealed a hexagonal layered structure without impurity phase for all samples and significant increase in the diffraction intensity ratio of I(003)/I(104) was observed. Rietveld refinement further confirmed the reduced cationic disordering in Li slab by such pressing treatment, and the smallest disordering was observed for sample S4 with only 1.3% Ni ions on Li lattice position. The electrochemical testing showed an improvement in electrochemical behavior for those pressing treated samples. The calculation of diffusion coefficients using EIS data showed improved Li diffusion coefficient after pressing treatment. The sample S4 presented a diffusion coefficient of 4.36 × 10−11 cm2·s−1, which is almost 3.5 times the value of untreated sample.

Recent genomic sequencing of the foxtail millet, an abiotic, stress-tolerant crop, has provided a great opportunity for novel gene discovery and functional analysis of this popularly-grown grass. However, few stress-mediated gene families have been studied. Aldehyde dehydrogenases (ALDHs) comprise a gene superfamily encoding NAD (P) +-dependent enzymes that play the role of "aldehyde scavengers", which indirectly detoxify cellular ROS and reduce the effect of lipid peroxidation meditated cellular toxicity under various environmental stresses. In the current paper, we identified a total of 20 ALDH genes in the foxtail millet genome using a homology search and a phylogenetic analysis and grouped them into ten distinct families based on their amino acid sequence identity. Furthermore, evolutionary analysis of foxtail millet reveals that both tandem and segmental duplication contributed significantly to the expansion of its ALDH genes. The exon-intron structures of members of the same family in foxtail millet or the orthologous genes in rice display highly diverse distributions of their exonic and intronic regions. Also, synteny analysis shows that the majority of foxtail millet and rice ALDH gene homologs exist in the syntenic blocks between the two, implying that these ALDH genes arose before the divergence of cereals. Semi-quantitative and real-time quantitative PCR data reveals that a few SiALDH genes are expressed in an organ-specific manner and that the expression of a number of foxtail millet ALDH genes, such as, SiALDH7B1, SiALDH12A1 and SiALDH18B2 are up-regulated by osmotic stress, cold, H2O2, and phytohormone abscisic acid (ABA). Furthermore, the transformation of SiALDH2B2, SiALDH10A2, SiALDH5F1, SiALDH22A1, and SiALDH3E2 into Escherichia coli (E.coli) was able to improve their salt tolerance. Taken together, our results show that genome-wide identification characteristics and expression analyses provide unique opportunities for assessing the functional roles of foxtail millet ALDH genes in stress responses.