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1.
Toxics ; 12(6)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38922103

RESUMO

Groundwater contaminated by benzene and toluene is a common issue, posing a threat to the ecosystems and human health. The removal of benzene and toluene under sulfate-reducing condition is well known, but how the bacterial community shifts during this process remains unclear. This study aims to evaluate the shift in bacterial community structure during the biodegradation of benzene and toluene under sulfate-reducing condition. In this study, groundwater contaminated with benzene and toluene were collected from the field and used to construct three artificial samples: Control (benzene 50 mg/L, toluene 1.24 mg/L, sulfate 470 mg/L, and HgCl2 250 mg/L), S1 (benzene 50 mg/L, toluene 1.24 mg/L, sulfate 470 mg/L), and S2 (benzene 100 mg/L, toluene 2.5 mg/L, sulfate 940 mg/L). The contaminants (benzene and toluene), geochemical parameters (sulfate, ORP, and pH), and bacterial community structure in the artificial samples were monitored over time. By the end of this study (day 90), approximately 99% of benzene and 96% of toluene could be eliminated in both S1 and S2 artificial samples, while in the Control artificial sample the contaminant levels remained unchanged due to microbial inactivation. The richness of bacterial communities initially decreased but subsequently increased over time in both S1 and S2 artificial samples. Under sulfate-reducing condition, key players in benzene and toluene degradation were identified as Pseudomonas, Janthinobacterium, Novosphingobium, Staphylococcus, and Bradyrhizobium. The results could provide scientific basis for remediation and risk management strategies at the benzene and toluene contaminated sites.

2.
bioRxiv ; 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38328095

RESUMO

It is widely believed that tissue mechanical properties, determined mainly by the extracellular matrix (ECM), are actively maintained. However, despite its broad importance to biology and medicine, tissue mechanical homeostasis is poorly understood. To explore this hypothesis, we developed mutations in the mechanosensitive protein talin1 that alter cellular sensing of ECM stiffness. Mutation of a novel mechanosensitive site between talin1 rod domain helix bundles 1 and 2 (R1 and R2) shifted cellular stiffness sensing curves, enabling cells to spread and exert tension on compliant substrates. Opening of the R1-R2 interface promotes binding of the ARP2/3 complex subunit ARPC5L, which mediates the altered stiffness sensing. Ascending aortas from mice bearing these mutations show increased compliance, less fibrillar collagen, and rupture at lower pressure. Together, these results demonstrate that cellular stiffness sensing regulates ECM mechanical properties. These data thus directly support the mechanical homeostasis hypothesis and identify a novel mechanosensitive interaction within talin that contributes to this mechanism.

3.
Oncol Rep ; 51(3)2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38240088

RESUMO

Bone marrow stromal cell antigen 2 (BST2) is a type II transmembrane protein that serves critical roles in antiretroviral defense in the innate immune response. In addition, it has been suggested that BST2 is highly expressed in various types of human cancer and high BST2 expression is related to different clinicopathological parameters in cancer. The molecular mechanism underlying BST2 as a potential tumor biomarker in human solid tumors has been reported on; however, to the best of our knowledge, there has been no review published on the molecular mechanism of BST2 in human solid tumors. The present review focuses on human BST2 expression, structure and functions; the molecular mechanisms of BST2 in breast cancer, hepatocellular carcinoma, gastrointestinal tumor and other solid tumors; the therapeutic potential of BST2; and the possibility of BST2 as a potential marker. BST2 is involved in cell membrane integrity and lipid raft formation, which can activate epidermal growth factor receptor signaling pathways, providing a potential mechanistic link between BST2 and tumorigenesis. Notably, BST2 may be considered a universal tumor biomarker and a potential therapeutical target.


Assuntos
Neoplasias da Mama , Neoplasias Hepáticas , Humanos , Feminino , Antígeno 2 do Estroma da Médula Óssea/metabolismo , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Neoplasias da Mama/patologia , Transdução de Sinais , Biomarcadores Tumorais/genética , Biologia
4.
ACS Nano ; 18(5): 4495-4506, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38265359

RESUMO

Recent advances in scanning probe microscopy methodology have enabled the measurement of tip-sample interactions with picometer accuracy in all three spatial dimensions, thereby providing a detailed site-specific and distance-dependent picture of the related properties. This paper explores the degree of detail and accuracy that can be achieved in locally quantifying probe-molecule interaction forces and energies for adsorbed molecules. Toward this end, cobalt phthalocyanine (CoPc), a promising CO2 reduction catalyst, was studied on Ag(111) as a model system using low-temperature, ultrahigh vacuum noncontact atomic force microscopy. Data were recorded as a function of distance from the surface, from which detailed three-dimensional maps of the molecule's interaction with the tip for normal and lateral forces as well as the tip-molecule interaction potential were constructed. The data were collected with a CO molecule at the tip apex, which enabled a detailed visualization of the atomic structure. Determination of the tip-substrate interaction as a function of distance allowed isolation of the molecule-tip interactions; when analyzing these in terms of a Lennard-Jones-type potential, the atomically resolved equilibrium interaction energies between the CO tethered to the tip and the CoPc molecule could be recovered. Interaction energies peaked at less than 160 meV, indicating a physisorption interaction. As expected, the interaction was weakest at the aromatic hydrogens around the periphery of the molecule and strongest surrounding the metal center. The interaction, however, did not peak directly above the Co atom but rather in pockets surrounding it.

5.
Rev Sci Instrum ; 94(10)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37796097

RESUMO

Quantum key distribution (QKD) research has yielded highly fruitful results and is currently undergoing an industrialization transformation. In QKD systems, electro-optic modulators are typically employed to prepare the required quantum states. While various QKD systems operating at GHz repetition frequency have demonstrated exceptional performance, they predominantly rely on instruments or printed circuit boards to fulfill the driving circuit function of the electro-optic modulator. Consequently, these systems tend to be complex with low integration levels. To address this challenge, we have introduced a modulator driver integrated circuit in 0.18 µm SiGe BiCMOS technology. The circuit can generate multiple-level driving signals with a clock frequency of 1.25 GHz and a rising edge of ∼50 ps. Each voltage amplitude can be independently adjusted, ensuring the precise preparation of quantum states. The measured signal-to-noise ratio was more than 17 dB, resulting in a low quantum bit error rate of 0.24% in our polarization-encoding system. This work will contribute to the advancement of QKD system integration and promote the industrialization process in this field.

6.
Rev Sci Instrum ; 94(10)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37815424

RESUMO

As the number of qubits in quantum computing increases, the scalability of existing qubit circuit structures and control systems may become insufficient for large-scale expansion and high-fidelity control. To address this challenge, we propose a behavioral-level model of a superconducting qubit and its control electronics, followed by a co-simulation to evaluate their performance. In this paper, we present the modeling process, simulation procedure, and resulting design specifications for the qubit control system. Our co-simulation approach utilizes MATLAB and Simulink, enabling us to derive critical circuit design specifications, such as the required Digital-to-Analog Converter (DAC) resolution, which should be 8 bits or higher, to achieve high-fidelity control. By taking into account factors such as DAC sampling rates, integral and differential nonlinearities, and filter characteristics, we optimize the control system for efficient and accurate qubit manipulation. Our model and simulation approach offer a promising solution to the scalability challenges in quantum computing, providing valuable insights for the design of large-scale superconducting quantum computing systems.

7.
Chem Commun (Camb) ; 59(61): 9368-9371, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37432127

RESUMO

Intermolecular fluorocyclization of indoles with anthranilates, which proceeded smoothly to give diverse indoloquinazolinone architectures under mild reaction conditions, has been developed. A wide range of substrates were compatible with this cyclization system. The synthetic fluorinated compounds could be modified by their conversion to various substituted quinazolinones for drug discovery. In addition, this protocol has been applied to the concise total synthesis of bioactive natural alkaloids phaitanthrins A-B, cephalanthrin A and cruciferane.

8.
Small ; 19(47): e2304751, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37485645

RESUMO

The dendrite growth and parasitic reactions that occur on Zn metal anode (ZMA)/electrolyte interface hinder the development of aqueous zinc ion batteries (AZIBs) in next-generation renewable energy storage systems. Fortunately, reconstructing the inner Helmholtz layer (IHL) by introducing an electrolyte additive, is viewed as one of the most promising strategies to harvest the stable ZMA. Herein, (4-chloro-3-nitrophenyl) (pyridin-4-yl) methanone (CNPM) with quadruple functional groups is introduced into the ZnSO4 electrolyte to reshape the interface between ZMA and electrolyte and change the solvation structure of Zn2+ . Density functional theory (DFT) calculations manifest that the ─C═O, ─Cl, ─C═N─, and ─NO2 functional groups of CNPM interact with metallic Zn simultaneously and adsorb on the ZMA surface in a parallel arrangement manner, thus forming a water-poor IHL and creating well-arranged ion transportation channels. Furthermore, theoretical calculations and experimental results demonstrate that CNPM absorbed on the Zn anode surface can serve as zincophilic sites for inducing uniform Zn deposition along the (002) plane. Benefiting from the synergistic effect of these functions, the dendrite growth and parasitic reactions are suppressed significantly. As a result, ZMA exhibits a long cycle life (2900 h) and high coulombic efficiency (CE) (500 cycles) in the ZnSO4 +CNPM electrolyte.

9.
Reprod Sci ; 30(11): 3243-3252, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37277689

RESUMO

At present, the effect of body fat distribution on female reproductive health is still inconclusive. The purpose of our study was to analyze the correlation between female infertility rates and the fat mass portion of the android region to the gynoid region (the A/G ratio) among US women of reproductive age. Female infertility is defined as a failure to get pregnant after 12 months of unprotected sexual activity. A total of 3434 women of reproductive age were included in this study as part of the 2013-2018 National Health and Nutrition Examination Survey (NHANES). The A/G ratio was used to assess the body fat distribution of participants. Based on the comprehensive study design and sample weights, it was determined that the A/G ratio was associated with female infertility primarily through logistic regression analyses. After adjusting for potential confounders, the multivariate regression analysis indicated an increase in the A/G ratio was correlated with an increase in the prevalence of female infertility (OR = 4.374, 95% CI:1.809-10.575). Subgroup analyses showed an increased prevalence of infertility in non-Hispanic Whites (P = 0.012), non-diabetic individuals (P = 0.008), individuals under 35 years old (P = 0.002), and individuals with secondary infertility (P = 0.01). The trend tests and smooth curve fitting illustrate a linear trend between the A/G ratio and female infertility. Future researches are warranted to confirm the causal relationship between body fat distribution and female infertility, which may provide an insight into future prevention and treatment of female infertility.


Assuntos
Infertilidade Feminina , Humanos , Feminino , Adulto , Masculino , Inquéritos Nutricionais , Estudos Transversais , Infertilidade Feminina/epidemiologia , Distribuição da Gordura Corporal , Saúde da Mulher , Índice de Massa Corporal , Absorciometria de Fóton
10.
J Orthop Surg Res ; 18(1): 397, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264353

RESUMO

PURPOSE: It is known that muscle strength and muscle mass play a crucial role in maintaining bone mineral density (BMD). Despite this, there are uncertainties about how muscle mass, lower extremity muscular strength, and BMD are related. We examined the impact of lower extremity muscle strength and mass on BMD in the general American population using cross-sectional analysis. METHODS: In the study, we extracted 2165 individuals from the National Health and Nutrition Examination Survey 1999-2002. Multivariate logistic regression models were used to examine the association between muscle strength, muscle mass, and BMD. Fitted smoothing curves and generalized additive models were also performed. To ensure data stability and avoid confounding factors, subgroup analysis was also conducted on gender and race/ethnicity. RESULTS: After full adjustment for potential confounders, significant positive associations were detected between peak force (PF) [0.167 (0.084, 0.249) P < 0.001], appendicular skeletal muscle index (ASMI) [0.029 (0.022, 0.036) P < 0.001], and lumbar spine BMD. A positive correlation was also found between PF, ASMI, and pelvis and total BMD. Following stratification by gender and race/ethnicity, our analyses illustrated a significant correlation between PF and lumbar spine BMD in both men [0.232 (0.130, 0.333) P < 0.001] and women [0.281 (0.142, 0.420) P < 0.001]. This was also seen in non-Hispanic white [0.178 (0.068, 0.288) P = 0.002], but not in non-Hispanic black, Mexican American and other race-ethnicity. Additionally, there was a positive link between ASMI and BMD in both genders in non-Hispanic whites, and non-Hispanic blacks, but not in any other racial group. CONCLUSION: PF and ASMI were positively associated with BMD in American adults. In the future, the findings reported here may have profound implications for public health in terms of osteopenia and osteoporosis prevention, early diagnosis, and treatment.


Assuntos
Densidade Óssea , Força Muscular , Adulto , Humanos , Feminino , Masculino , Densidade Óssea/fisiologia , Inquéritos Nutricionais , Estudos Transversais , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiologia , Absorciometria de Fóton , Brancos
11.
J Bone Miner Metab ; 41(5): 631-641, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37291468

RESUMO

INTRODUCTION: There is evidence that individual antioxidants may increase bone mineral density (BMD) in patients with low BMD. However, the association between overall dietary antioxidant intake and BMD is unclear. The objective of this study was to examine how overall dietary antioxidant intake is related to BMD. MATERIALS AND METHODS: A total of 14,069 people participated in the National Health and Nutrition Examination Survey (NHANES) between 2005 and 2010. Dietary Antioxidant Index (DAI) was calculated from the intake of vitamins A, C, E, zinc, selenium, and magnesium, which indicates a nutritional tool to assess the overall antioxidant properties of the diet. The correlation between the Composite Dietary Antioxidant Index (CDAI) and BMD was examined using multivariate logistic regression models. In addition to fitting smoothing curves, we fitted generalized additive models as well. Furthermore, to ensure data stability and avoid confounding factors, subgroup analysis was also conducted on gender and body mass index (BMI). RESULTS: A significant association was demonstrated by the study between CDAI and total spine BMD (ß = 0.001, 95% CI 0-0.001, P = 0.00039). And just like that, CDAI was positively correlated with femoral neck (ß = 0.003, 95% CI 0.003-0.004, P < 0.00001) and trochanter (ß = 0.004, 95% CI 0.003-0.004, P < 0.00001). In the gender subgroup analysis, CDAI maintained a strong positive correlation with femoral neck and trochanter BMD in males and females. Nevertheless, the link with total spine BMD was only observed in males. In addition, in the subgroup analysis stratified by BMI, CDAI showed a significantly positive relation to BMD of the femoral neck and trochanter in each group. However, the significant relationship between CDAI and BMD of the total spine was only maintained when BMI was above 30 kg/m2. CONCLUSION: This study found that CDAI correlated positively with femoral neck, trochanter, and total spine BMD. This suggests that intake of a diet rich in antioxidants can reduce the risk of low bone mass and osteoporosis.


Assuntos
Densidade Óssea , Osteoporose , Masculino , Feminino , Humanos , Estados Unidos/epidemiologia , Antioxidantes , Inquéritos Nutricionais , Osteoporose/epidemiologia , Dieta
12.
Nanoscale Adv ; 4(23): 5062-5069, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36504734

RESUMO

For filamentary resistive random-access memory (RRAM) devices, the switching behavior between different resistance states usually occurs abruptly, while the random formation of conductive filaments usually results in large fluctuations in resistance states, leading to poor uniformity. Schottky barrier modulation enables resistive switching through charge trapping/de-trapping at the top-electrode/oxide interface, which is effective for improving the uniformity of RRAM devices. Here, we report a uniform RRAM device based on a MXene-TiO2 Schottky junction. The defect traps within the MXene formed during its fabricating process can trap and release the charges at the MXene-TiO2 interface to modulate the Schottky barrier for the resistive switching behavior. Our devices exhibit excellent current on-off ratio uniformity, device-to-device reproducibility, long-term retention, and endurance reliability. Due to the different carrier-blocking abilities of the MXene-TiO2 and TiO2-Si interface barriers, a self-rectifying behavior can be obtained with a rectifying ratio of 103, which offers great potential for large-scale RRAM applications based on MXene materials.

13.
RSC Adv ; 12(52): 33688-33695, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36505674

RESUMO

Porous structure design and the content regulation of heteroelements have been proved to be effective strategies to boost photocatalytic H2 generation activity of graphitic carbon nitride (g-C3N4) based photocatalyst. Herein, a series of porous graphitic carbon nitride with high concentration of oxygen (g-C3N4-O) photocatalysts were synthesized via in situ polymerization process using colloidal SiO2 as oxygen source. The content of oxygen within the g-C3N4-O photocatalysts could be tuned by adjusting the amount of added colloidal SiO2 during the preparation procedure. The introduced oxygen replaced two-coordinated nitrogen atom, influencing band edge position and localized electron distribution, thereby enhancing visible light harvesting and photoelectric conversion. As a result, the g-C3N4-O photocatalyst with an optimal oxygen content (8.39 wt%) showed 10.5 fold enhancement in H2 evolution rate compared to that of bulk g-C3N4, attributed to the porous structure and high concentration of incorporated oxygen.

14.
Chem Commun (Camb) ; 58(96): 13325-13328, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36325927

RESUMO

A metal catalyst free approach for regioselective ortho-chlorination of anilines has been developed using a secondary amine as the organocatalyst and sulfuryl chloride as the halogen source under mild conditions. A wide range of substrates were compatible with this catalytic system. In addition, this catalytic protocol has been applied to the efficient synthesis of bioactive compounds and modification of drug derivatives. Further studies indicated that the anionic trichloride species was responsible for the ortho-selectivity.


Assuntos
Compostos de Anilina , Halogenação , Compostos de Anilina/química , Aminas , Cloretos , Halogênios
15.
Sci Total Environ ; 847: 157465, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35868370

RESUMO

The throughput of materials fuels the economic process and underpins social well-being. These materials eventually return to the environment as waste or emissions. They can have significant environmental impacts throughout life cycle stages, such as biodiversity loss, adverse health effects, water stress, and climate change. China is the largest resource extractor globally, but the endpoint environmental impacts and the role of possible socioeconomic drivers associated with its resource extraction remain unclear. Here, we account for and analyze the two endpoint environmental impacts associated with China's resource extraction from 2000 to 2017 and quantify the relative contributions of various socioeconomic factors using structural decomposition analysis. The results show that the environmental impacts of China's resource extraction peaked in 2010. There was a significant decline from 2010 to 2017, in which human health damage decreased by 32.8 % and ecosystem quality damage decreased by 55.8 %. On the consumer side, the advancement in China's urbanization process led to an increase in the environmental impacts of urban residents' consumption, and the effect of investment on the environmental impacts decreased significantly after 2010. Decreases in the intensity of the environmental impacts in most sectors and improvements in production structure could reduce the impacts of resource extraction on human health and ecosystems.


Assuntos
Ecossistema , Urbanização , China , Meio Ambiente , Humanos , Fatores Socioeconômicos
16.
Sci Rep ; 12(1): 4536, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35296737

RESUMO

Though effective in theoretical simulation, the established traffic control models and optimization algorithms will result in model mismatch or even control strategy failure in actual application. However, they are commonly adopted in traffic signal control research, resulting in the unavailability of many exceptional control algorithms in practice. Simulation should function as a bridge between theoretical research and actual application, allowing the gap between the two to be communicated and made up for. However, an effective connection between the two has yet to be established to enable simulation methods in existing traffic control research. To this end, we designed and developed a simulation platform for "Online Application-HILS (Hardware-in-the-Loop Simulation)-Practice" integration over traffic signal control. In this paper, the architecture and characteristics of the integrated simulation platform were described. Besides, the function of each module of the platform was detailed, followed by listing simulation examples for six complex scenarios, with the active control scenario being selected for simulation comparison analysis. The findings demonstrated extensive road network simulation with the integrated simulation platform, multidimensional control variables, control strategies with support, as well as stable and reliable operation. It can be used to verify several sorts of traffic control simulation with variable dimensions.


Assuntos
Algoritmos , Simulação por Computador
17.
Micromachines (Basel) ; 13(2)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35208308

RESUMO

With the research and the development of graphene-based materials, new sensors based on graphene compound materials are of great significance to scientific research and the consumer market. However, in the past ten years, due to the requirements of sensor accuracy, reliability, and durability, the development of new graphene sensors still faces many challenges in the future. Due to the special structure of graphene, the obtained characteristics can meet the requirements of high-performance sensors. Therefore, graphene materials have been applied in many innovative sensor materials in recent years. This paper introduces the important role and specific examples of sensors based on graphene and its base materials in biomedicine, photoelectrochemistry, flexible pressure, and other fields in recent years, and it puts forward the difficulties encountered in the application of graphene materials in sensors. Finally, the development direction of graphene sensors has been prospected. For the past two years of the COVID-19 epidemic, the detection of the virus sensor has been investigated. These new graphene sensors can complete signal detection based on accuracy and reliability, which provides a reference for researchers to select and manufacture sensor materials.

18.
Tissue Eng Regen Med ; 19(3): 491-503, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35119649

RESUMO

BACKGROUND: Nowadays, biological tissue engineering is a growing field of research. Biocompatibility is a key indicator for measuring tissue engineering biomaterials, which is of great significance for the replacement and repair of damaged tissues. METHODS: In this study, using gelatin, carboxymethyl chitosan, and sodium alginate, a tissue engineering material scaffold that can carry cells was successfully prepared. The material was characterized by Fourier transforms infrared spectroscopy. In addition, the prepared scaffolds have physicochemical properties, such as swelling ratio, biodegradability. we observed the biocompatibility of the hydrogel to different adult stem cells (BMSCs and ADSCs) in vivo and in vitro. Adult stem cells were planted on gelatin-carboxymethyl chitosan-sodium alginate (Gel/SA/CMCS) hydrogels for 7 days in vitro, and the survival of stem cells in vitro was observed by live/died staining. Gel/SA/CMCS hydrogels loaded with stem cells were subcutaneously transplanted into nude mice for 14 days of in vivo culture observation. The survival of adult stem cells was observed by staining for stem cell surface markers (CD29, CD90) and Ki67. RESULTS: The scaffolds had a microporous structure with an appropriate pore size (about 80 µm). Live/died staining showed that adult stem cells could stably survive in Gel/SA/CMCS hydrogels for at least 7 days. After 14 days of culture in nude mice, Ki67 staining showed that the stem cells supported by Gel/SA/CMCS hydrogel still had high proliferation activity. CONCLUSION: Gel/SA/CMCSs hydrogel has a stable interpenetrating porous structure, suitable swelling performance and degradation rate, can promote and support the survival of adult stem cells in vivo and in vitro, and has good biocompatibility. Therefore, Gel/SA/CMCS hydrogel is a strong candidate for biological tissue engineering materials.


Assuntos
Alginatos , Quitosana , Alginatos/química , Animais , Materiais Biocompatíveis/química , Quitosana/química , Gelatina/química , Hidrogéis/química , Antígeno Ki-67 , Camundongos , Camundongos Nus , Células-Tronco
19.
Int J Mol Sci ; 24(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36613957

RESUMO

Quinoa straw is rich in hemicellulose, and it could be hydrolyzed into xylose. It is a promising energy resource alternative that acts as a potential low-cost material for producing xylitol. In this study, quinoa straw was used as a substrate subjected to the hydrolysis of dilute sulfuric acid solution. Based on the production of xylose and inhibitors during hydrolysis, the optimal conditions for the hydrolysis of hemicellulose in quinoa straw were determined. Detoxification was performed via activated carbon adsorption. The optimal detoxification conditions were determined on the basis of major inhibitor concentrations in the hydrolysate. When the addition of activated carbon was 3% at 30 °C for 40 min, the removal of formic acid, acetic acid, furfural, and 5-HMF could reach 66.52%, 64.54%, 88.31%, and 89.44%, respectively. In addition to activated carbon adsorption, vacuum evaporation was further conducted to perform two-step detoxification. Subsequently, the detoxified hydrolysate was used for xylitol fermentation. The yield of xylitol reached 0.50 g/g after 96 h of fermentation by Candida tropicalis (CICC 1779). It is 1.2-fold higher than that obtained through the sole vacuum evaporation method. This study validated the feasibility of xylitol production from quinoa straw via a biorefinery process.


Assuntos
Chenopodium quinoa , Xilitol , Xilose , Carvão Vegetal , Fermentação , Hidrólise
20.
Environ Sci Pollut Res Int ; 29(12): 18213-18224, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34686962

RESUMO

Environmental pressures have rapidly increased in various regions worldwide due to globalization. Thus, sustainable consumption and production are crucial for sustainable resource development. The material footprint (MF) of 180 countries was calculated from 1995 to 2015, and spatial autocorrelation analysis was conducted to investigate the spatiotemporal trend of the global MF. The results show that the global MF presented an upward trend from 1995 to 2015, increasing by 83%, and we find that the global per capita MF exhibits clustering, with an increasing trend during the study period. The findings indicate that resource consumption is similar in neighboring areas, especially in countries with a high MF surrounded by countries with a high MF (high-high clustering) and countries with low-low clustering. In addition, the number of countries with high clustering increased during the study period. We should take advantage of clustering, improve resource utilization, increase the technical carrying capacity, and develop energy-saving technologies. In African regions with low-low clustering, the economy of the surrounding areas should be stimulated to strengthen economic and technological clustering. In addition, advanced technology should be incorporated to improve the efficiency of using natural resources. This study can provide a reference for the spatial distribution of sustainable resource development.


Assuntos
Conservação dos Recursos Naturais , Recursos Naturais , China , Conservação dos Recursos Naturais/métodos , Desenvolvimento Econômico , Desenvolvimento Sustentável , Tecnologia
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