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The paper explores the effectiveness of hands-on learning (HOL) as a student-centered model to train first year chemical engineering undergraduates. The pedagogical design of the course uses laboratory sessions, lectures, reflection sessions, projects, and assessments to achieve the course learning outcomes. The adopted assessment methodology (100% continuous assessment with no end-of-semester examination) aims at evaluating the quality of learning and mastery of higher order skills by students. The student feedback has been encouraging with many students finding the HOL methodology useful in offering meaningful opportunities to gain knowledge and acquire a breadth of higher-order skills.

Atmospheric water is among the most important water sources for plants in arid ecosystems and plays an important role in facilitating drought stress survival in plants. However, little is known about the specific physiological benefits of foliar water uptake (FWU) for woody plants inhabiting arid desert areas. The objective of this study was to explore the physiological responses of Calligonum mongolicum to atmospheric water uptake by the assimilating branches, with a special focus on the FWU effect on shoot water status and photosynthesis. To this end, the canopies of natural C. mongolicum plants in a desert region of northwestern China were humidified in a field in-situ misting experiment and a long-term wetting experiment, during which physiological measurements of plant water relations and photosynthetic capacity were performed, alongside the observation of FWU by H218O isotopic tracing. Following the in-situ misting experiment, the water potential of the assimilating branches was significantly higher than that of the secondary branches at midnight, suggesting that FWU resulted in a reverse water potential gradient in C. mongolicum at the branch level. The 18O isotope was markedly enriched in the assimilating branches, secondary branches, and trunk xylem following the foliar uptake of 18O labeled water, indicating that the water uptake from the atmosphere by the assimilating branches could replenish the stem. The relative water content and water potential of the assimilating branches were significantly increased by FWU. The net photosynthetic rate, stomatal conductance, and maximum photochemical efficiency of C. mongolicum plants were markedly increased following the wetting treatment. Our results clearly show that C. mongolicum is capable of FWU, and that the absorbed water could be transported downward through the xylem and improve the branch water status and photosynthetic capacity. These findings provide a new perspective for deepening our understanding of the drought survival mechanism of plants in arid environments.

Human cytomegalovirus (HCMV) enters host by glycoprotein B (gB)-mediated membrane fusion upon receptor-binding to gH/gL-related complexes, causing devastating diseases such as birth defects. Although an X-ray crystal structure of the recombinant gB ectodomain at postfusion conformation is available, the structures of prefusion gB and its complex with gH/gL on the viral envelope remain elusive. Here, we demonstrate the utility of cryo electron tomography (cryoET) with energy filtering and the cutting-edge technologies of Volta phase plate (VPP) and direct electron-counting detection to capture metastable prefusion viral fusion proteins and report the structures of glycoproteins in the native environment of HCMV virions. We established the validity of our approach by obtaining cryoET in situ structures of the vesicular stomatitis virus (VSV) glycoprotein G trimer (171 kD) in prefusion and postfusion conformations, which agree with the known crystal structures of purified G trimers in both conformations. The excellent contrast afforded by these technologies has enabled us to identify gB trimers (303kD) in two distinct conformations in HCMV tomograms and obtain their in situ structures at up to 21 Å resolution through subtomographic averaging. The predominant conformation (79%), which we designate as gB prefusion conformation, fashions a globular endodomain and a Christmas tree-shaped ectodomain, while the minority conformation (21%) has a columnar tree-shaped ectodomain that matches the crystal structure of the "postfusion" gB ectodomain. We also observed prefusion gB in complex with an "L"-shaped density attributed to the gH/gL complex. Integration of these structures of HCMV glycoproteins in multiple functional states and oligomeric forms with existing biochemical data and domain organization of other class III viral fusion proteins suggests that gH/gL receptor-binding triggers conformational changes of gB endodomain, which in turn triggers two essential steps to actuate virus-cell membrane fusion: exposure of gB fusion loops and unfurling of gB ectodomain.

BackgroundPrevious studies have shown the poor prognosis of metastatic breast cancer including bone metastasis. The early prediction and intervention of invasive breast carcinoma with bone metastasis are crucial to the outcomes of patients. The purpose of our study is to test the hypothesis that the collagen deposition of primary breast cancer can be used as a quantitative biomarker for the early prediction of bone metastasis.MethodsA total of sixty breast cancer patients were included in our study, and the surgical specimens of these patients were divided into three groups: patients with no metastasis (group 1), lymph node metastasis (group 2), and bone metastasis (group 3). Masson's trichrome staining and hematoxylin and eosin staining were applied to all primary breast cancers. Collagen area percentage and tumor cell measurement of each sample were measured by HistoQuest software.ResultsMeasurement results of collagen area percentage (%) in primary breast tumors were 32.39 ± 13.30, 25.37 ± 11.10, and 22.71 ± 8.91 for groups 1, 2, and 3, respectively. The corresponding P values were 0.0779 (group 1 vs. group 2), 0.4086 (group 2 vs. group 3), and 0.0102 (group 1 vs. group 3). The correlation between collagen area percentage and tumor cell measurement were group 1 (P = 0.5927, r = -0.1273), group 2 (P = 0.5711, r = -0.1348), and group 3 (P = 0.0003, r = -0.7253).ConclusionsThe collagen deposition of primary breast cancer can be used as a quantitative biomarker for the early prediction of bone metastasis.

The efficacy and safety of combining open-configuration magnetic resonance imaging (MRI) and an optical surgical navigation system (OSNS) for guidance of percutaneous liver cryoablation were evaluated in a pig model. This approach was successfully executed in eight test pigs under general anesthesia. Another two pigs spared from ablation served as controls. MRI studies, blood testing, and pathologic examinations were performed at various time points. MRI-determined minimal and maximal cryolesion diameters were 19.4 ± 1.5 mm and 44.3 ± 1.8 mm, respectively (mean volume, 8.32 ± 2.41 cm3). The lesions were readily visible by MRI on postablation Days 2 and 7, all presenting as teardrop-shaped regions of low signal intensity in T1-weighted images and high signal intensity in T2-weighted images. Mean serum alanine aminotransferase concentration transiently increased postablation, and mean blood platelet count transiently declined (both, P < 0.05). The mean necrotic tissue volume generated by pathologic assessment was less than that determined by MRI (4.24 ± 2.3 cm3 vs. 8.32 ± 2.41 cm3, P < 0.05). Cell necrosis isotherms in MRI views were within 6.0 ± 0.8 mm of cryolesion edges. Inflammatory cell infiltrates and exuberant granulation tissue surrounded necrotic areas on postablation Day 7. Combined open-configuration MRI and OSNS guidance of percutaneous liver cryoablation proved effective and safe in our animal model. This concept seems ideal for precision image-guided hepatic ablation in a clinical setting.

Dendritic cell (DC) based immunotherapy is a promising approach for cancer treatment and has been approved in clinical settings for decades. Clinical trials have demonstrated relatively poor therapeutic efficacy. The efficacy of DC immunotherapy is strongly influenced by their ability to migrate to the draining lymph nodes (LNs). Therefore, it is critical to deliver DCs and monitor the in vivo biodistributions of DCs after administration. The purpose of this study is to determine whether a novel injection route of DCs improves DC migration to LNs, tissues, organs and lymphatics. In the present study, a modified method was investigated to acquire DCs from mouse bone marrow. Cultured antibody labeled DCs were analyzed by flow cytometry. India ink was used to visualize mouse abdominal LNs and PKH26 was utilized to label DCs for intraperitoneal (IP) injection, results were evaluated by histology. Our results showed that large amounts of DCs with a relatively high purity were acquired. IP injection of india ink marked the abdominal LNs and PKH26 labeled DCs showed IP was an effective administration route to increase the absorption of viable DCs, and different time points after IP inject showed no significant difference of the migrated DCs. The findings indicated that large amounts of high purity DCs can be acquired through our method and IP injection accelerates DCs migration to abdominal LNs, which can be directly translated to clinical settings, especially for abdominal cancers. This study makes a foundation for future researches of DC-based immunotherapy as a treatment modality against cancer.

In this paper, a transcritical carbon dioxide power generation system based on a vortex tube is studied, which has the advantage of the self-condensation of carbon dioxide. The thermodynamic performance of the system was investigated by establishing a mathematical model. The results showed that under fundamental working conditions, the system could output a net power of 271.72 kW, and the thermal efficiency as well as the exergy efficiency of the system could reach 7.38% and 27.09%, respectively. Exergy analysis showed that the turbine had the greatest exergy loss among the system’s components, followed by the vortex tube, pump, heater and cooler. Parameter analysis showed that increasing the outlet pressure and inlet temperature of the vortex tube can improve the thermal efficiency and exergy efficiency of the system. In addition, the improvement in the turbine component’s efficiency is the most beneficial to the system’s performance, among which the turbine’s efficiency has the greatest impact. Carbon dioxide can be effectively liquified by expanding it in the vortex tube, and its liquefaction ratio increases with the decrease in the vortex tube’s inlet temperature and the increase in the vortex tube’s inlet pressure.

Due to the low decomposition potential of H2O and its corrosive effect to Zn foil, the Zn metal battery with aqueous electrolytes operates within a narrow electrochemical window and exhibits low anode utilization ratio. Fluorinated carbonate ester, exhibiting low highest occupied molecular orbital (HOMO) energy level, is suitable for constructing high‐voltage batteries, yet its application in Zn metal battery has been scarcely explored. Herein, we propose an electrolyte based on fluorinated solvents and ethoxy (pentafluoro) cyclotriphosphazene (PFPN) additive, which exhibits a high decomposition voltage of 2.75 V in Zn batteries. The fluorinated carbonate esters possess non‐flammability and exhibit reduced solvation capacity which in turn promotes the incorporation of anions into Zn2+ solvation shell. Consequently, an anion‐derived interface layer is formed on Zn anode, aiding the compact and planar growth of deposited Zn. Therefore, the Zn//Zn cell exhibits an impressive Zn utilization of 91 % for 140 h, a level seldom reported previously. Benefitting from the oxidation resistant solvents and cathode‐electrolyte interface layer formed by PFPN additive, the Zn//graphite dual‐ions battery shows an extended cycling life of 1000 cycles. Furthermore, an anode‐free cell was constructed and stably operated for 100 cycles, with a notably high average discharge midpoint voltage of 1.84 V. [ABSTRACT FROM AUTHOR]

In the present work, we report a "two-in-one" strategy to construct single-linker-based pillar-layered metal–organic frameworks (PL-MOFs) guided by reticular chemistry via an in situ "one-pot" approach. Two carboxyl groups and one pyridine group are integrated into one molecular skeleton to form bifunctional organic linkers via the reaction of pyridine-containing aldehyde and bicarboxylate-containing o-phenylenediamine. During the synthesis of organic linkers, two zinc-based PL-MOFs, non-interpenetrated HIAM-3016-op and two-fold interpenetrated HIAM-3017-op, can be simultaneously constructed. The different interpenetrations for these two PL-MOFs can be attributed to the increased length of the pyridine-containing moiety. HIAM-3017-op can be utilized for Cr2O72− detection with excellent sensitivity and selectivity. The present work not only provides a novel insight to design and prepare PL-MOFs with specific structures guided by reticular chemistry, but also indicates the universality of the in situ "one-pot" strategy to construct porous materials. [ABSTRACT FROM AUTHOR]