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•LiBr hydrate/acetone system is efficient for converting crystalline cellulose (MCC) to 5-hydroxymethylfurfural (5-HMF).•75.1% yield of 5-HMF together with 13.7% yield of glucose were ...obtained from MCC conversion with the addition of AlCl3.•DFT calculations indicated glucose isomerization rather than crystalline cellulose hydrolysis is the rate-determining step in cellulose conversion into 5-HMF.•Produced 5-HMF can be efficiently recovered by hyper-cross-linked polymer adsorption.•reaction system can be recycled 5 times without reducing 5-HMF selectivity.
5-hydroxymethylfurfural (5-HMF) is a crucial biomss-derived fuel precursor with versatile conversion pathways to advanced fuels. However, direct production of 5-HMF from crystalline cellulose is critical challenging due to the inefficient deconstruction of recalcitrant cellulose structure. Molten salt hydrates (MSHs) are unique in cellulose deconstruction and dissolution. In this work, a biphasic system of LiBr hydrate/acetone was established. It was found that 93.4% yield of 5-HMF can be efficiently converted from fructose without any catalysts. With the addition of AlCl3 to adjust Lewis acidity, an enhanced 5-HMF yield of 75.1% together with 13.7% of glucose were directly produced from cellulose, showing a promising carbon balance of 88.8%. A proposed mechanism for cellulose conversion was studied by density functional theory (DFT) calculations, demonstrating that the isomerization of glucose to fructose rather than crystalline cellulose hydrolysis was the rate-determining step. After reaction, the formed 5-HMF can be efficiently recycled from solvent via hyper-cross-linked polymer adsorption and the reaction system can be recycled for more than 5 times without reducing 5-HMF selectivity.
Saccharification of cellulose into glucose is a key step for the utilization of lignocellulose. Molten salt hydrate (MSH) is unique in selective hydrolysis of cellulose into glucose but the ...separation of formed glucose from MSH is challenging due to the high solubility of glucose in MSH. To address this issue, this work developed a method where a small dosage of MSH was applied to impregnate cellulose and convert it into water-soluble sugar with the degree of polymerization (DP) lower than 6, which can be readily hydrolyzed into glucose under mild conditions without sacrificing selectivity. Under the optimized impregnation condition at 110 °C for 2 h, cellulose was selectively converted into water-soluble sugar with a yield of 87.5%. Then the MSH can be efficiently dissolved and removed by anti-solvent isolation with
n
-butanol, resulting in a sugar recovery of 84.3%. We showed that the separation efficiency was influenced by anti-solvent polarity and oligosaccharides chain-length. Moreover, the production and separation of water-soluble sugar from corn stover was also investigated. 88.9% yield of water-soluble sugar was obtained from the impregnation of corn stover under the optimized reaction conditions. With the addition of
n
-butanol as an anti-solvent, the water-soluble sugar can be recovered from MSH with a selectivity of 86.7%.
Graphical Abstract
Liquid fuel intermediates could be produced via aldol condensation reaction between furfural or 5-hydroxymethylfurfural (HMF) and acetone. It was found that iron-modified MCM-41 zeolite can be an ...effective Lewis acid catalyst for C—C bond formation via aldol condensation of furfural or HMF with acetone. The 4-(2-furyl)-3-buten-2-one and 1, 5-di-2-furanyl-1, 4-pentadien-3-one (FAc and F2Ac), or 1, 5-di-2-furanyl-1, 4-pentadien-3-one and 1, 5-bis(5- hydroxlmethyl)-2-furanyl-1, 4-pentadien-3-one (HAc and H2Ac), as two main condensation products of furfural with acetone or HMF with acetone, were observed. After 24 h at 160 °C, 86.9% conversion of furfural with 60.0% yield of the FAc as well as 7.5% yield of the F2Ac and 88.9% conversion of the HMF with 41.1% yield of the HAc as well as 3.5% yield of the H2Ac were achieved. Although furfural or HMF conversion was almost same after 24 h at 160 °C, iron-modified MCM-41 zeolite catalyst displayed an enhanced selectivity to condensation products of furfural with acetone. In addition, catalysts showed an improved selectivity to the F2Ac and H2Ac at higher reaction temperature. The reusability and regeneration studies showed that iron-modified MCM-41 zeolite catalyst could not be reused directly, but could be regenerated by calcination in air, and the catalytic performance of regenerated catalyst was acceptable.
It remains unclear whether very preterm (VP) infants have the same level of brain structure and function as full-term (FT) infants. In addition, the relationship between potential differences in ...brain white matter microstructure and network connectivity and specific perinatal factors has not been well characterized.
This study aimed to investigate the existence of potential differences in brain white matter microstructure and network connectivity between VP and FT infants at term-equivalent age (TEA) and examine the potential association of these differences with perinatal factors.
A total of 83 infants were prospectively selected for this study: 43 VP infants (gestational age, or GA: 27-32 weeks) and 40 FT infants (GA: 37-44 weeks). All infants at TEA underwent both conventional magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). Significant differences in white matter fractional anisotropy (FA) and mean diffusivity (MD) images between the VP and FT groups were observed using tract-based spatial statistics (TBSS). The fibers were tracked between each pair of regions in the individual space, using the automated anatomical labeling (AAL) atlas. Then, a structural brain network was constructed, where the connection between each pair of nodes was defined by the number of fibers. Network-based statistics (NBS) were used to examine differences in brain network connectivity between the VP and FT groups. Additionally, multivariate linear regression was conducted to investigate potential correlations between fiber bundle numbers and network metrics (global efficiency, local efficiency, and small-worldness) and perinatal factors.
Significant differences in FA were observed between the VP and FT groups in several regions. These differences were found to be significantly associated with perinatal factors such as bronchopulmonary dysplasia (BPD), activity, pulse, grimace, appearance, respiratory (APGAR) score, gestational hypertension, and infection. Significant differences in network connectivity were observed between the VP and FT groups. Linear regression results showed significant correlations between maternal years of education, weight, the APGAR score, GA at birth, and network metrics in the VP group.
The findings of this study shed light on the influence of perinatal factors on brain development in VP infants. These results may serve as a basis for clinical intervention and treatment to improve the outcome of preterm infants.
osteochondral lesion of the talus (OLT) is a common disease in the physically active population, and extracorporeal shock wave therapy (ESWT) is a noninvasive treatment. We hypothesized that ...microfracture (MF) combined with ESWT may have great potential to become a novel combination treatment of OLT.
the OLT patients who received MF + ESWT or MF + platelet-rich plasma (PRP) injection were retrospectively included, with a minimal follow up of 2y. The daily activating VAS, exercising VAS, and American Orthopedic Foot and Ankle Society Ankle-Hindfoot Score (AOFAS) were used to assess the efficacy and functional outcome, and ankle MRI T2 mapping was used to evaluate the quality of regenerated cartilage in the OLT patients.
only transient synovium-stimulated complications were found during the treatment sessions; the complication rate and daily activating VAS did not have differences between groups. MF + ESWT had a higher AOFAS and a lower T2 mapping value than MF + PRP at the 2y follow up.
the MF + ESWT had superior efficacy for treating OLT, which resulted in better ankle function and more hyaline-like regenerated cartilage, superior to the traditional MF + PRP.
Very few studies have been made to investigate functional activity changes in occult spastic diplegic cerebral palsy (SDCP). The purpose of this study was to analyze whole-brain resting state ...regional brain activity and functional connectivity (FC) changes in patients with SDCP.
We examined 12 occult SDCP and 14 healthy control subjects using resting-state functional magnetic resonance imaging. The data were analyzed using Resting-State fMRI Data Analysis Toolkit (REST) software. The regional homogeneity (ReHo), amplitude of low-frequency fluctuations (ALFF), and whole brain FC of the motor cortex and thalamus were analyzed and compared between the occult SDCP and control groups.
Compared with the control group, the occult SDCP group showed decreased ReHo regions, including the bilateral frontal, parietal, and temporal lobes, the cerebellum, right cingulate gyrus, and right lenticular nucleus, whereas an increased ReHo value was observed in the left precuneus, calcarine, fusiform gyrus, and right precuneus. Compared with the control group, no significant differences in ALFF were noted in the occult SDCP group. With the motor cortex as the region of interest, the occult SDCP group showed decreased connectivity regions in the bilateral fusiform and lingual gyrus, but increased connectivity regions in the contralateral precentral and postcentral gyrus, supplementary motor area, and the ipsilateral postcentral gyrus. With the thalamus being regarded as the region of interest, the occult SDCP group showed decreased connectivity regions in the bilateral basal ganglia, cingulate, and prefrontal cortex, but increased connectivity regions in the bilateral precentral gyrus, the contralateral cerebellum, and inferior temporal gyrus.
Resting-state regional brain activities and FC changes in the patients with occult SDCP exhibited a special distribution pattern, which is consistent with the pathology of the disease.
Spastic diplegic cerebral palsy (SDCP) is a common type of cerebral palsy (CP), which presents as a group of motor-impairment syndromes. Previous conventional MRI studies have reported abnormal ...structural changes in SDCP, such as periventricular leucomalacia. However, there are roughly 27.8% SDCP patients presenting normal appearance in conventional MRI, which were considered as occult SDCP. In this study, sixteen patients with occult SDCP and 16 age- and sex-matched healthy control subjects were collected and the data were acquired on a 3T MR system. We applied voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) analysis to investigate whole brain grey and white matter injury in occult SDCP. By using VBM method, the grey matter volume reduction was revealed in the bilateral basal ganglia regions, thalamus, insula, and left cerebral peduncle, whereas the white matter atrophy was found to be located in the posterior part of corpus callosum and right posterior corona radiata in the occult SDCP patients. By using TBSS, reduced fractional anisotropy (FA) values were detected in multiple white matter regions, including bilateral white matter tracts in prefrontal lobe, temporal lobe, internal and external capsule, corpus callosum, cingulum, thalamus, brainstem and cerebellum. Additionally, several regions of white matter tracts injury were found to be significantly correlated with motor dysfunction. These results collectively revealed the spatial patterns of whole brain grey and white matter injury in occult SDCP.
Cadium sulfide/titanium dioxide (CdS/TiO2) catalyst was prepared by two different methods: microemulsion-mediated solvothermal hydrolyzation (CdS/TiO2 (SH)) and in-situ sulfurization under ...supercritical conditions (CdS/TiO2 (SS)). The photocatalysts were characterized by nitrogen adsorption-desorption, X-ray diffraction, X-ray photoelectron spectra, UV-Vis absorption spectra, and PL spectra. Photodegradation reactions of three monomeric and one dimeric lignin model compounds, and kraft pine lignin (Indulin AT) were carried out at room temperature in a weak alkaline aqueous system by visible light irradiation with air bubbling. Quantitative results showed that these lignin model compounds and kraft lignin were effectively degraded. While both phenolic and non-phenolic lignin units are reactive, the phenolic units appeared to react faster and preferentially reacted.
Background:
Quantification of cardiac structure and function is essential for diagnostic interpretation and clinical decision making. We sought to establish cardiovascular magnetic resonance (CMR) ...reference values of left and right ventricular (LV and RV) morphology and function based on a large sample of healthy Chinese adults.
Methods:
Five hundred fifty validated healthy Chinese adults (aged 21–70 years; 323 men) free of hypertension, diabetes, and obesity were included in this study. All the subjects were stratified by gender (men and women) and age decades. On cine CMR, measurements of biventricular end-diastolic, end-systolic, and stroke volumes (EDV, ESV, and SV), ejection fraction (EF), and end-diastolic LV wall thickness (LVWT) and mass (LVM) were obtained.
Results:
Men had greater LVEDV (111.6 ± 19.8 vs. 94.6 ± 15.6 ml), LVESV (36.5 ± 9.8 vs. 28.2 ± 7.9 ml), LVM (121.1 ± 19.9 vs. 86.1 ± 14.5 g), global end-diastolic LVWT (8.1 ± 1.1 vs. 6.7 ± 1.0 mm), RVEDV (128.0 ± 23.6 vs. 101.7 ± 17.0 ml), and RVESV (53.5 ± 13.7 vs. 36.8 ± 8.9 ml), while women had greater LVEF (67.5 ± 5.4 vs. 70.4 ± 5.7%) and RVEF (58.5 ± 5.2 vs. 64.0 ± 5.3%) (all
p
< 0.001). For both men and women, age was negatively correlated with LVEDV (
r
= −0.31 and
r
= −0.32), LVESV (
r
= −0.37 and
r
= −0.47), RVEDV (
r
= −0.31 and
r
= −0.29), and RVESV (
r
= −0.33 and
r
= −0.44), while it was positively correlated with LVEF (
r
= 0.28 and
r
= 0.43) and RVEF (
r
= 0.28 and
r
= 0.41) (all
p
< 0.001). Aging was associated with increasing global end-diastolic LVWT and LVM/LVEDV in both sexes (all
p
< 0.001). Older age was associated with increasing LVM only in women (
r
= 0.36,
p
< 0.001), not in men (
r
= 0.05,
p
= 0.359).
Conclusions:
We systematically provide age-, sex-, and body size-specific CMR reference values for biventricular morphology and function based on a large sample of healthy Chinese adults. Biventricular structure and function are significantly associated with age and sex.
Molten salt hydrates (MSHs) are remarkable in breaking through the recalcitrant structure of microcrystalline cellulose and raw biomass. After being pretreated in 60 wt% LiBr at 130 °C for 2 h, ...cellulose crystallinity as well as degree of polymerization (DP) decreased. It was found that 91.3% yield of pretreated cellulose was removed from MSHs by filteration followed by being hydrolyzed into glucose with a high yield of 75.3% by dilute acid under mild reaction conditions. The pretreatment process also works on raw corn stover hydrolysis. After being pretreated at 100 °C for 5 h, 88.4% yield of cellulose in biomass was recovered and can be hydrolyzed into 54.9% yield of glucose with dilute acid. It was found that the cellulose in corn stover can be easier degraded compared with microcrystalline cellulose during MSHs pretreatment, which dues to the formation of acetic acid from hemicellulose hydrolysis. The proposed pretreatment technique presents a promising potential for glucose production from biomass in a commercial way.
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•MSHs pretreatment effectively decreased cellulose crystallinity and DP.•After being pretreated at 130°C for 2 h, 91.3% of cellulose was removed from MSHs via filtration.•Enhanced glucose yield of 75.3% was obtained from pretreated cellulose hydrolysis at mild condition.•88.4% cellulose recovery and 54.9% glucose yield were obtained from MSHs pretreatment and hydrolysis, respectively.
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