Modeling the impact of high thermal conductivity paper on the performance and life of power transformers.

Degradation of insulation paper is a key contributor to the failure of power transformers. Insulation degradation accelerates at elevated temperatures, which highlights the potential for better thermal management to prolong life. While several studies have analyzed the benefits of high thermal conductivity oil for reducing temperatures inside a transformer, this study is an initial assessment of the benefits of high thermal conductivity paper on transformer life. Blending particulates with cellulosic fibers offers a pathway for high thermal conductivity paper (with good dielectric properties), which can reduce internal temperatures. Presently, life extensions that can be achieved by the use of such thermally conducting papers were estimated, with the thermal conductivity of the paper being the key parameter under study. The analytical-numerical thermal model used in this study was validated against experimental measurements in a distribution transformer, adding confidence to the utility of the model. This model was then used to provide estimates of hot-spot temperature reduction resulting from the use of papers with higher thermal conductivity than baseline. Transformer life was predicted conventionally by tracking the degree of polymerization of paper over time, based on an Arrhenius model. Results indicate that increasing the thermal conductivity of paper from 0.2 W/mK (baseline) to 1 W/mK reduces the hot spot temperature by 10 °C. While degradation significantly depends on the moisture and oxygen content, the model shows that such a temperature reduction can increase life for all conditions, by as much as a factor of three.

Producing Cellulose Microfibrils at a High Solid Content with and without Mechanical or Enzymatic Pretreatment.

This study conducted a detailed evaluation of the feasibility of producing cellulose microfibrils (CMF) from a kraft-bleached hardwood pulp at high solid contents with and without pretreatments. CMFs produced by planetary ball milling at solid contents 17 and 28% were compared with those from 1 to 5% under the same milling conditions. Fiber pretreatments using a commercial endoglucanase and mechanical refining using a laboratory PFI mill were also applied before ball milling at a solid content of 28%. Two mechanisms of fiber fibrillation were identified from the results obtained: (i) ball and fiber/fibril interactions─the primary mechanism and (ii) interfiber/fibril frictional and tensional interactions─the secondary mechanism. The secondary mechanism plays an important role only in early-stage fibrillation and became less important as fibrillation proceeded in the later stage toward nanofibrillation. Improving fiber dispersion at lower solid content facilitated fibrillation. Endoglucanase pretreatment substantially shortened fibers to result in a "pulverized-like" CMF with short fibrils at an extended milling time. Mechanical refining of fibers facilitated fibrillation to result in CMFs with a morphology similar to that from runs without any fiber pretreatment but for a much shorter milling time. Both CMF water retention value (WRV) measurements and CMF suspension sedimentation experiments showed results consistent with imaging observations. The insights gained through this study provide relevant information with commercial significance regarding CMF production at high solids, which is not currently available in the literature.

[Establishment of a topographic map assessment system for facial and cervical wounds and scars of burn patients based on the Delphi method].

Objective: To construct a targeted and accurate evaluation system for facial and cervical wounds and scars of burn patients. Methods: The method combining literature analysis and survey research was adopted, and the basic principles of item system construction were followed. From June to August 2020, based on the aesthetic standards of facial and cervical plastic surgery, the topographic map assessment system for facial and cervical wounds and scars of burn patients was preliminarily formed, focusing on the assessment of wounds and scars in the necks and faces of patients after burns. In September 2020, 38 experts in the relevant fields were consulted in advance and the questionnaire was revised according to the experts' opinions. From December 2020 to March 2021, the Delphi method was applied to conduct inquiry by correspondence with 35 experts in relevant fields from Guangzhou, Shenzhen, Shanghai, Beijing, and other cities, who met the inclusion criteria, and the items were screened and established. The effective recovery rate of inquiry questionnaire was calculated to determine the level of enthusiasm of experts, the average authority coefficient of all items was calculated to determine the level of expert authority, the average importance expert score, the average coefficient of variation, and the average full score rate of all the third-level items were calculated to determine the concentration of expert opinions, the average coefficients of variation and Kendall's harmony coefficients of the importance, sensitivity, and operability expert scores of all the third-level items were calculated to determine the degree of coordination of expert opinions. The Kendall's harmony coefficients for the importance, sensitivity, and operability expert scores of all the third-level items were statistically analyzed with chi-square test. Results: Among the 35 experts consulted by Delphi method, mainly were male, aged (48±10) years, with 8-38 years of working experience, mainly with associate senior titles and above, all with a bachelor's degree or above education background, and of whom 11 were burn experts, 7 were wound repair experts, 4 were plastic surgery experts, and 13 were rehabilitation medicine experts. Finally, a topographic map assessment system for facial and cervical wounds and scars of burn patients was formed, including 4 first-level items, 21 second-level items, 40 third-level items, and 1 mask. The effective recovery rate of inquiry questionnaire was 100% (35/35). The average authority coefficient of all items was 0.89. The average importance expert score was 4.67, the average coefficient of variation of importance expert score was 0.01, and the average full score rate of all the third-level items was 86.3%. The average coefficients of variation of the importance, sensitivity, and operability expert scores of all the third-level items were 0.01, 0.01, and 0.02, respectively. The Kendall's harmony coefficients for the importance, sensitivity, and operability expert scores of all the third-level items were statistically significant (with χ2 values of 1 201.53, 745.67, and 707.07, respectively, P<0.05). Conclusions: The established topographic map assessment system for facial and cervical wounds and scars of burn patients has high scientificity and reliability, which can be used for the evaluation of facial and neck wounds or scars in burn patients.

[Effects of enhancing the expression of aryl hydrocarbon receptor in post-traumatic mice macrophages on the inflammatory cytokine level and bactericidal ability].

Objective: To explore the expression pattern of aryl hydrocarbon receptor (AhR) in mice peritoneal macrophages (PMs) after major trauma and analyze the effects of enhanced AhR expression on the inflammatory cytokine level and bactericidal ability after trauma. Methods: The experimental study method was used. Forty 6-8-week-old male C57BL/6J mice (the same mouse age, sex, and strain below) were divided into control group, post trauma hour (PTH) 2 group, PTH 6 group, and PTH 12 group according to the random number table (the same grouping method below), with 10 mice in each group. Mice in the latter 3 groups were constructed as severe trauma model with fracture+blood loss, while mice in control group were left untreated. The primary PMs (the same cells below) were extracted from the mice in control group, PTH 2 group, PTH 6 group, and PTH 12 group when uninjured or at PTH 2, 6, and 12, respectively. Then the protein and mRNA expressions of AhR were detected by Western blotting and real-time fluorescence quantitative reverse transcription polymerase chain reaction, respectively, and the gene expressions of AhR signaling pathway related molecules were analyzed by transcriptome sequencing. Twenty mice were divided into control group and PTH 6 group, with 10 mice in each group, and the PMs were extracted. The level of ubiquitin of AhR was detected by immunoprecipitation. Twelve mice were divided into dimethyl sulfoxide (DMSO) alone group, PTH 6+DMSO group, MG-132 alone group, and PTH 6+MG-132 group, with 3 mice in each group. After the corresponding treatment, PMs were extracted, and the protein expression of AhR was detected by Western blotting. Twenty mice were constructed as PTH 6 model. Then, the PMs were extracted and divided into empty negative control adenovirus (Ad-NC) group and AhR overexpression adenovirus (Ad-AhR) group. The protein expression of AhR was detected by Western blotting at 36 h after some PMs were transfected with the corresponding adenovirus. The rest cells in Ad-NC group were divided into Ad-NC alone group and Ad-NC+endotoxin/lipopolysaccharide (LPS) group, and the rest cells in Ad-AhR group were divided into Ad-AhR alone group and Ad-AhR+LPS group. The expressions of interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) in the cell supernatant were detected by enzyme-linked immunosorbent assay at 12 h after the corresponding treatment (n=6). Twenty mice were obtained to extract PMs. The cells were divided into control+Ad-NC group, PTH 6+Ad-NC group, control+Ad-AhR group, and PTH 6+Ad-AhR group, and the intracellular bacterial load was detected by plate spread method after the corresponding treatment (n=6). Data were statistically analyzed with one-way analysis of variance, least significant difference test, analysis of variance for factorial design, and independent sample t test. Results: Compared with 1.16±0.28 of control group, the protein expressions of AhR in PMs in PTH 2 group (0.59±0.14), PTH 6 group (0.72±0.16), and PTH 12 group (0.71±0.17) were all significantly decreased (P<0.05). The overall comparison of the difference of AhR mRNA expression in PMs among control group, PTH 2 group, PTH 6 group, and PTH 12 group showed no statistical significance (P>0.05). The AhR signaling pathway related molecules included AhR, AhR inhibitor, cytochrome P450 family member 1b1, cytochrome P450 family member 11a1, heat shock protein 90, aryl hydrocarbon receptor-interaction protein, and heat shock protein 70 interaction protein. The heat shock protein 90 expression of PMs in PTH 2 group was higher than that in control group, while the expressions of other molecules did not change significantly after trauma. Compared with that in control group, the level of ubiquitin of AhR in PMs in PTH 6 group was increased. Compared with that in DMSO alone group, the protein expression of AhR in PMs in PTH 6+DMSO group was decreased, while that in PMs in MG-132 alone group had no significant change. Compared with that in PTH 6+DMSO group, the protein expression of AhR in PMs in PTH 6+MG-132 group was up-regulated. At transfection hour 36, compared with that in Ad-NC group, the protein expression of AhR in PMs in Ad-AhR group was increased. At treatment hour 12, compared with those in Ad-NC+LPS group, the expressions of IL-6 and TNF-α in PM supernatant of Ad-AhR+LPS group were significantly decreased (with t values of 4.80 and 3.82, respectively, P<0.05). The number of intracellular bacteria of 1×106 PMs in control+Ad-NC group, PTH 6+Ad-NC group, control+Ad-AhR group, and PTH 6+Ad-AhR group was (3.0±1.8), (41.8±10.2), (1.8±1.2), and (24.2±6.3) colony forming unit, respectively. Compared with that in PTH 6+Ad-NC group, the number of intracellular bacteria of PMs in PTH 6+Ad-AhR group was significantly decreased (t=3.61, P<0.05). Conclusions: Ubiquitin degradation of AhR in PMs of mice after major trauma results in decreased protein expression of AhR. Increasing the expression of AhR in post-traumatic macrophages can reduce the expressions of LPS-induced inflammatory cytokines IL-6 and TNF-α, and improve the bactericidal ability of macrophages after trauma.

In Situ Lignin Adhesion for High-Performance Bamboo Composites.

Bamboo composite is an attractive candidate for structural materials in applications such as construction, the automotive industry, and logistics. However, its development has been hindered due to the use of harmful petroleum-derived synthetic adhesives or low-bonding biobased adhesives. Herein, we report a novel bioadhesion strategy based on in situ lignin bonding that can process natural bamboo into a scalable and high-performance composite. In this process, lignin bonds the cellulose fibrils into a strong network via a superstrong adhesive interface formed by hydrogen bonding and nanoscale entanglement. The resulting in situ glued-bamboo (glubam) composite exhibits a record-high shear strength of ∼4.4 MPa and a tensile strength of ∼300 MPa. This in situ lignin adhesion strategy is facile, highly scalable, and cost-effective, suggesting a promising route for fabricating strong and sustainable structural bamboo composites that sequester carbon and reduce our dependence on petrochemical-based adhesives.

Uncertainty and influencing factors of the placement error of three-dimensional conformal intensity-modulated radiotherapy for thoracic tumors.

OBJECTIVE: Radiation therapy is an important method for the treatment of chest tumors. This study discussed the placement error of three-dimensional (3D) conformal intensity-modulated radiotherapy in patients with different types of chest tumors and analyzed the relevant influencing factors. PATIENTS AND METHODS: 100 patients with chest tumors diagnosed and treated in our hospital from March 2016 to March 2018 were randomly selected as research subjects, including 42 cases of esophageal cancer, 44 cases of breast cancer, and 14 cases of lung cancer. All patients underwent 3D conformal radiotherapy. The setup errors of patients with esophageal cancer, breast cancer, and lung cancer were detected after 3D conformal radiotherapy. Besides, the influencing factors of 3D conformal for thoracic tumors were analyzed by multiple linear regression analysis. RESULTS: After 3D conformal radiotherapy, the systematic errors of patients with esophageal cancer in X-axis, Y-axis, and Z-axis were -0.10, 1.26 and 0.07, respectively, while the random errors in X-axis, Y-axis, and Z-axis were 1.18, -1.14, and 0.97 respectively. The times for the absolute values of the positioning error with a range of ≤5 mm in X-axis, Y-axis, and Z-axis were 40 (95.24%), 2 (4.76%) and 36 (85.71%), while these with a range of >5 mm in X-axis, Y-axis, and Z-axis were 6 (14.29%), 41 (97.62%) and 1 (2.38%), respectively. For patients with breast cancer, the systematic errors and random errors in X-axis, Y-axis, and Z-axis are -0.19, 1.19, and 0.15, as well as 0.97, 0.02 and 1.29, respectively. The times for the absolute values of the positioning error with a range of ≤5 mm and >5 mm were 41 (93.18%), 3 (6.82%), and 36 (81.82%), as well as 8 (18.18%), 42 (95.45%) and 2 (4.55%), severally. For patients with lung cancer, the systematic errors and random errors in X-axis, Y-axis, and Z-axis were 0.14, 1.42, and 0.15, as well as 1.35, -0.23 and 1.12, respectively. The times for the absolute values of the positioning error with the range of ≤5 mm and >5 mm were 14 (93.33%), 1 (6.67%), and 11 (73.33%), as well as 4 (26.67%), 14 (93.33%) and 1 (6.67%) after 3D conformal radiotherapy. After multiple linear regression analyses, gender and lung volume were the influencing factors of Z-axis setup error, and the lesion location was the influence factor of Y-axis setup error (p<0.05). CONCLUSIONS: There are certain positioning errors in the X-axis, Y-axis, and Z-axis directions of thoracic tumors receiving 3D conformal radiotherapy. Gender, lung volume, and lesion location are all important factors that affect the placement error. The results of this study provide a certain reference for the positioning error of radiation therapy for thoracic tumors, which is conducive to improving the accuracy of radiotherapy and better protecting the surrounding tissues.

Characterizing lignin-containing microfibrillated cellulose based on water interactions, fibril properties, and imaging.

Morphological characterization of microfibrillated cellulose (MFC) is critically important to process control in production and product specification for trade and product development yet is extremely difficult. This study evaluated several indirect methods for relative comparison of the morphology of lignin-free and lignin-containing ((L)MFCs). The (L)MFCs studied were produced using a commercial grinder through different passes from a dry lap bleached kraft eucalyptus pulp, a virgin mixed (maple and birch) unbleached kraft hardwood pulp, and two virgin-unbleached kraft softwood (loblolly pine) pulps with one bleachable grade (low lignin content) and one liner grade (high lignin content). The (L)MFCs were indirectly characterized using techniques based on water interactions, i.e., water retention value (WRV) and fibril suspension stability, as well as fibril properties, i.e., cellulose crystallinity and fine content. Optical microscopy and scanning electron microscopy were also applied to directly visualize the (L)MFCs to provide some objective measure of the morphology of the (L)MFCs. The results indicate that most measures such as WRV, cellulose crystallinity, fine content cannot be used to compare (L)MFCs from different pulp fibers. Measures based on water interactions such as (L)MFC WRV and suspension stability appeared can provide some degree of indirect assessment. This study provided the utilities and limits of these indirect methods for relative comparison of the morphologies of (L)MFCs.

[Evaluation of thermal environment and human thermal comfort in 8 types of public places from 2019 to 2021].

Objective: To evaluate the thermal environment of different types of public places and the thermal comfort of employees, so as to provide scientific basis for the establishment of microclimate standards and health supervision requirements. Methods: From June 2019 to December 2021, 50 public places (178 times) of 8 categories in Wuxi were selected, including hotels, swimming pools (gymnasiums), bathing places, shopping malls (supermarkets), barber shops, beauty shops, waiting rooms (bus station) and gyms. In summer and winter, microclimate indicators such as temperature and wind speed were measured in all kinds of places, combined with the work attire and physical activity of employees in the places. Fanger thermal comfort equation and center for the built environment (CBE) thermal comfort calculation tool were used to evaluate the predicted mean vote (PMV), predicted percent dissatisfied (PPD) and standard effective temperature (SET) according to the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 55-2020. The modification effects of seasonal and temperature control conditions on thermal comfort were analyzed. The consistency of GB 37488-2019 "Hygienic Indicators and Limits in Public Places" and ASHRAE 55-2020 evaluation results on thermal environment was compared. Results: The thermal sensation of hotel, barber shop staff and the gym front-desk staff were moderate, while the thermal sensation of swimming place lifeguard, bathing place cleaning staff and gym trainer were slightly warm in summer and winter. Waiting room (bus station) cleaning and working staff, shopping mall staff felt slightly warm in summer and moderate in winter. Service staff in bathing places felt slightly warm in winter, while staff in beauty salons felt slightly cool in winter. The thermal comfort compliance of hotel cleaning staff and shopping mall staff in summer was lower than that in winter (χ(2)=7.01, 7.22, P=0.008, 0.007). The thermal comfort compliance of shopping mall staff in the condition of air conditioning off was higher than that in the condition of air conditioning on (χ(2)=7.01, P=0.008). The SET values of front-desk staff in hotels with different health supervision levels were significantly different (F=3.30, P=0.024). The PPD value and SET value of the front-desk staff, and the PPD value of cleaning staff of hotels above three stars were lower than those of hotels below three stars (P<0.05). The thermal comfort compliance of front-desk staff and cleaning staff in hotels above three stars was higher than that in hotels below three stars (χ(2)=8.33, 8.09, P=0.016, 0.018). The consistency of the two criteria was highest among waiting room (bus station) staff (100.0%, 1/1) and lowest among gym front-desk staff (0%, 0/2) and waiting room (bus station) cleaning staff (0%, 0/1) . Conclusion: There are different degrees of thermal discomfort in different seasons, under the condition of air conditioning and health supervision, and the microclimate indicators can not fully reflect the thermal comfort of human body. The health supervision of microclimate should be strengthened, the applicability of health standard limit value should be evaluated in many aspects, and the thermal comfort of occupational group should be improved.

[Study on mandibular movement trajectory and virtual occlusal pre-adjustment under light and heavy bite force].

Objective: To investigate the influence of light and heavy bite force on the mandibular movement trajectories, and the influence of bite force on virtual occlusal pre-adjustment of digital full crown. Methods: From October 2021 to March 2022, 10 postgraduate volunteers (3 males and 7 females, aged 22-26 years) were recruited from Peking University School and Hospital of Stomatology. Maxillary and mandibular digital models of the participants were obtained by intraoral scanning. Jaw relations were digitally transferred under heavy bite force and mandibular movement trajectories under light and heavy bite force were recorded by jaw motion analyser. Three mandibular markers were chosen, namely the mesial proximal contact point of the central incisor (incisal point) and the mesial buccal cusp tips of the bilateral first molars. The three-dimensional displacements of the markers under two kinds of bite force in the intercuspal position (ICP), the sagittal projection of the three-dimensional displacements in the protrusive edge-to-edge position, and the coronal projection of the three-dimensional displacements in the lateral edge-to-edge position of upper and lower posterior teeth were measured. Single-sample t-test was used to compare the three-dimensional displacements and the corresponding sagittal projection and coronal projection with 0, respectively. The left maxillary central incisor and left mandibular first molar were virtually prepared by the reverse engineering software. Then dental design software was used to design digital full crown using the copy method. The mandibular movement trajectories under light and heavy bite force were separately used to guide virtual occlusal pre-adjustment. The three-dimensional deviations (mean deviations and root mean square) between the lingual surface of the left maxillary central incisor or the occlusal surface of the left mandibular first molar and that of the natural tooth before preparation were calculated (light bite force group and heavy bite force group), and the differences between the two groups were compared by the paired t-test. Results: Under the two kinds of bite force, the three-dimensional displacements of the markers in the ICP were (0.217±0.135), (0.210±0.133) and (0.237±0.101) mm, respectively; the sagittal projection of the three-dimensional displacements of the markers in the protrusive edge-to-edge position were (0.204±0.133), (0.288±0.148) and (0.292±0.136) mm, respectively; the coronal projection of the three-dimensional displacements of the mesial buccal cusp tips of the bilateral first molars in the lateral edge-to-edge position were (0.254±0.140) and (0.295±0.190) mm, respectively. The differences between the above displacements and 0 were statistically significant (P<0.05). The results of occlusal pre-adjustment showed that the mean deviations of the lingual surface of the left maxillary central incisor in the light and heavy bite force groups were (0.215±0.036) and (0.195±0.041) mm (t=3.95, P=0.004), respectively. The mean deviations of the occlusal surface of the left mandibular first molar were (0.144±0.084) and (0.100±0.096) mm (t=0.84, P=0.036), respectively. Conclusions: Both the light and heavy bite force have an influence on the mandibular movement trajectories. Virtual occlusal pre-adjustment of prostheses with mandibular movement trajectories under heavy bite force can obtain morphology of lingual or occlusal surfaces closer to the natural teeth before preparation.

Neoadjuvant chemoradiotherapy versus neoadjuvant chemotherapy followed by minimally invasive esophagectomy for locally advanced esophageal squamous cell carcinoma: a prospective multicenter randomized clinical trial.

BACKGROUND: Neoadjuvant therapy is recommended for locally advanced esophageal cancer, but the optimal strategy remains unclear. We aimed to evaluate the safety and efficacy of neoadjuvant chemoradiotherapy (nCRT) versus neoadjuvant chemotherapy (nCT) followed by minimally invasive esophagectomy (MIE) for locally advanced esophageal squamous cell carcinoma (ESCC). PATIENTS AND METHODS: Eligible patients staged as cT3-4aN0-1M0 ESCC were randomly assigned (1 : 1) to the nCRT or nCT group stratified by age, cN stage, and centers. The chemotherapy, based on paclitaxel and cisplatin, was administered to both groups, while concurrent radiotherapy was added for the nCRT group; then MIE was carried out. The primary endpoint was 3-year overall survival. This study is registered with ClinicalTrials.gov (NCT03001596). RESULTS: A total of 264 patients were eligible for the intention-to-treat analysis. By 30 November 2021, 121 deaths had occurred. The median follow-up was 43.9 months (interquartile range 36.6-49.3 months). The overall survival in the intention-to-treat population was comparable between the nCRT and nCT strategies [hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.58-1.18; P = 0.28], with a 3-year survival rate of 64.1% (95% CI 56.4% to 72.9%) versus 54.9% (95% CI 47.0% to 64.2%), respectively. There were also no differences in progression-free survival (HR 0.83, 95% CI 0.59-1.16; P = 0.27) and recurrence-free survival (HR 1.07, 95% CI 0.71-1.60; P = 0.75), although the pathological complete response in the nCRT group (31/112, 27.7%) was significantly higher than that in the nCT group (3/104, 2.9%; P < 0.001). Besides, a trend of lower risk of recurrence was observed in the nCRT group (P = 0.063), while the recurrence pattern was similar (P = 0.802). CONCLUSIONS: NCRT followed by MIE was not associated with significantly better overall survival than nCT among patients with cT3-4aN0-1M0 ESCC. The results underscore the pending issue of the best strategy of neoadjuvant therapy for locally advanced bulky ESCC.

Emerging Engineered Wood for Building Applications.

The building sector, including building operations and materials, was responsible for the emission of ∼11.9 gigatons of global energy-related CO2 in 2020, accounting for 37% of the total CO2 emissions, the largest share among different sectors. Lowering the carbon footprint of buildings requires the development of carbon-storage materials as well as novel designs that could enable multifunctional components to achieve widespread applications. Wood is one of the most abundant biomaterials on Earth and has been used for construction historically. Recent research breakthroughs on advanced engineered wood products epitomize this material's tremendous yet largely untapped potential for addressing global sustainability challenges. In this review, we explore recent developments in chemically modified wood that will produce a new generation of engineered wood products for building applications. Traditionally, engineered wood products have primarily had a structural purpose, but this review broadens the classification to encompass more aspects of building performance. We begin by providing multiscale design principles of wood products from a computational point of view, followed by discussion of the chemical modifications and structural engineering methods used to modify wood in terms of its mechanical, thermal, optical, and energy-related performance. Additionally, we explore life cycle assessment and techno-economic analysis tools for guiding future research toward environmentally friendly and economically feasible directions for engineered wood products. Finally, this review highlights the current challenges and perspectives on future directions in this research field. By leveraging these new wood-based technologies and analysis tools for the fabrication of carbon-storage materials, it is possible to design sustainable and carbon-negative buildings, which could have a significant impact on mitigating climate change.

Setup error of electronic portal image device in IMRT for thoracic tumors and its influence.

OBJECTIVE: The aim of this study was to analyze the setup error of the electronics portal image device (EPID) in intensity-modulated radiation therapy (IMRT) for thoracic tumors and the influence on the outward expansion distance of the target area. PATIENTS AND METHODS: A total of 202 patients with chest tumors admitted to our hospital from March 2016 to March 2018 were selected as the observation subjects. All patients were treated with IMRT. The original plan was developed based on the SM90 obtained by the planning target volume (PTV) expansion method, and the new plan was obtained by shifting the isocenter coordinates of the treatment plan according to the positioning error value obtained by EPID. Before the treatment, EPID scans were performed. The electronic radiation field images (ERIs) were registered with the digitally reconstructed radiographic images (DRRs) generated by the treatment planning system using the image registration software, and the setup errors in the X, Y, and Z directions were further measured. The PTV was developed according to ERIs, and the setup error was simulated to obtain the PTV with 95% internal target volume (ITV) reaching the prescribed dose under the condition of a setup error. The outward expansion distance of clinical target volume (CTV) → PTV was calculated. RESULTS: In this experiment, the setup errors in X, Y, and Z directions were (-2.00±1.16) mm, (0.16±1.14) mm, and (-0.55±1.16) mm, respectively. The systematic error in the Z direction was -3.00 mm, and the random error in the X direction was 3.30 mm. The CTV → PTV outward expansion distance was set as 7, 8 and 7 mm in the X direction, Y direction and Z direction, respectively. At this time, under the presence of setup error, the PTV D95 and the ITV V100 in the new plan were (62.23±3.85) Gy and (97.51±1.56) %, respectively, effectively ensuring that 95% ITV of 90% patients reached the prescribed dose. In contrast, the ITV D95 and ITV V100 in the presence of setup error were (56.11±5.26) Gy and (90.15±3.12) %, respectively, at a CTV → PTV outward expansion distance of 5 mm, which could not guarantee that 95% ITV of 90% patients reached the prescribed dose. In the presence of a setup error, the double-lung 5 Gy irradiation of the total heart volume (V5), the double-lung 20 Gy irradiation of the total heart volume (V20), mean lung dose (MLD), mean heart dose (MHD), and D1 cm3 of the new plan increased by 0.89%, 0.29%, 0.13%, 0.06%, and 5 Gy, respectively, compared with the original plan. CONCLUSIONS: In general, the first treatment of radiotherapy in thoracic tumors mostly has a certain degree of setup error, which is most evident in the X direction. When the CTV → PTV outward expansion distance is set at 7, 8, and 7 mm in the X direction, Y direction, and Z direction, respectively, it can effectively ensure that 95% ITV reach the prescribed dose in 90% of patients in the presence of a setup error. EPID helps to achieve the desired effect of radiotherapy, improves the efficacy of radiotherapy, and reduces the side effects caused by radiotherapy errors.

Morphological and rheological properties of cellulose nanofibrils prepared by post-fibrillation endoglucanase treatment.

Post-fibrillation endoglucanase treatment was employed to reduce the entanglement of cellulose nanofibrils (CNFs) produced with low extent of mechanical milling. The results showed that post-fibrillation endoglucanase treatment can effectively reduce the fibril degree of polymerization (DP) values and therefore entanglement. Cellulose DP was reduced from 520 for CNFs prepared by milling using a SuperMassColloider with 1 pass to 225 after endoglucanase treatment at a low dosage of 1 mg protein/g fibril for 24 h. Endoglucanase treatment can also effectively reduce the fibril mean diameter from 66 nm to 25 nm. Applying post-fibrillation endoglucanase treatment produced more uniform CNFs than the feed CNFs from pure mechanical treatment. All CNFs suspensions prepared by post-fibrillation endoglucanase treatment were non-Newtonian (except at very low concentrations below 0.5 wt%) with shear thinning behavior. Post-fibrillation endoglucanase treatment reduced the viscosity of CNF suspensions due to decreasing fibril DP values and the extent of entanglement.

Polycomb contraction differentially regulates terminal human hematopoietic differentiation programs.

BACKGROUND: Lifelong production of the many types of mature blood cells from less differentiated progenitors is a hierarchically ordered process that spans multiple cell divisions. The nature and timing of the molecular events required to integrate the environmental signals, transcription factor activity, epigenetic modifications, and changes in gene expression involved are thus complex and still poorly understood. To address this gap, we generated comprehensive reference epigenomes of 8 phenotypically defined subsets of normal human cord blood. RESULTS: We describe a striking contraction of H3K27me3 density in differentiated myelo-erythroid cells that resembles a punctate pattern previously ascribed to pluripotent embryonic stem cells. Phenotypically distinct progenitor cell types display a nearly identical repressive H3K27me3 signature characterized by large organized chromatin K27-modification domains that are retained by mature lymphoid cells but lost in terminally differentiated monocytes and erythroblasts. We demonstrate that inhibition of polycomb group members predicted to control large organized chromatin K27-modification domains influences lymphoid and myeloid fate decisions of primary neonatal hematopoietic progenitors in vitro. We further show that a majority of active enhancers appear in early progenitors, a subset of which are DNA hypermethylated and become hypomethylated and induced during terminal differentiation. CONCLUSION: Primitive human hematopoietic cells display a unique repressive H3K27me3 signature that is retained by mature lymphoid cells but is lost in monocytes and erythroblasts. Intervention data implicate that control of this chromatin state change is a requisite part of the process whereby normal human hematopoietic progenitor cells make lymphoid and myeloid fate decisions.

[Culture of pluripotent stem cell-derived hepatocytes and organoids].

Liver is one of the most important organs in the human body. Liver diseases are also a major threat to human health and longevity. Hepatic decompensation treatment is quite difficult due to multiple reasons. Extracorporeal liver support devices are unable to solve this problem, and there is a severe shortage of orthotopic liver transplant donors. Study of pluripotent stem cell-derived hepatocytes and organoids can determine not only hepatocyte fate, but also liver development, regeneration mechanisms, and pathophysiology. Furthermore, it can be used for drug screening in order to provide a stable source of functional hepatocytes for future transplantation therapy. Culture of pluripotent stem cell-derived hepatocytes and organoids has a self-organizing process similar to liver development, i.e., starting with changes in several key factors, and eventually forming functionally complex cells/organs. This paper introduces the main methods and progress of pluripotent stem cell-derived hepatocytes and organoids, with hope to provide clues for future research.

The social and occupational consequences of the COVID-19 pandemic among patients with multiple sclerosis in three distinct populations: A web-based cross-sectional survey.

Background: The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes the disease COVID-19, has caused a pandemic that has rapidly affected the whole world and caused a significant threat to public health. The aim of this study was to investigate and analyze the social and occupational effects of the COVID-19 pandemic on patients with multiple sclerosis (MS) in three different countries: China, Spain, and Cuba. Methods: A cross-sectional survey was designed to assess the social and occupational effects of the COVID-19 pandemic in MS patients in these three countries, using a 25-item anonymous online questionnaire, structured into three sections. Quantitative data are expressed as mean (standard deviation), and quantitative data as absolute frequency and percentage. Results: A total of 361 participants responded to the questionnaire: 194 from China, 104 from Spain, and 63 from Cuba. We found no cases of COVID-19 among Chinese patients with MS, and few cases in Spain and Cuba. Respondents reported different levels of impact on relationships with friends, family, and colleagues, and patients in all three countries described increased use of digital or social media platforms. Spanish patients reported a significantly less negative impact than those in Cuba and China. Mental and cognitive effects were similar in all three countries, although China seemed to have a better situation. We also found that the time spent exercising decreased at specific points during the pandemic, but with few changes in dietary habits. Patients reported little or no change in their means of transport in all three countries. Most patients in all three countries reported little or no physical deterioration, especially in Chinese patients (82.47%), compared to the Spanish (70.20%) and Cuban respondents (73.02%). In general, patients from all three countries demonstrated confidence in overcoming the COVID-19 pandemic, although to a lesser extent among Spanish respondents. Conclusions: During the pandemic, family support was more effective in China than in Cuba and Spain. Neither COVID-19 infections nor the number of MS relapses increased significantly during lockdown in any of the three countries. Regarding their economic situation, Spanish MS patients reported a significantly less severe negative impact than those in Cuba and China. Patients from all three countries used digital or social media platforms more frequently, probably to maintain personal relationships. Chinese and Cuban respondents were more confident of the control of the pandemic than the Spanish, who were more pessimistic.

Introducción: El nuevo coronavirus de tipo 2, causante del síndrome respiratorio agudo severo o COVID-19, se ha expandido rápidamente a nivel mundial, convirtiéndose en una grave amenaza para la salud pública en forma de pandemia. El objetivo de este estudio es analizar los efectos sociolaborales de la pandemia de COVID-19 en pacientes con esclerosis múltiple (EM) en 3 países diferentes (China, España y Cuba). Métodos: Diseñamos un estudio transversal para valorar los efectos sociolaborales de la pandemia de COVID-19 en pacientes con EM procedentes de China, España y Cuba mediante un cuestionario digital de 25 preguntas divididas en 3 apartados. Los datos cuantitativos se expresan como medias y desviaciones estándar, mientras que los datos cualitativos se expresan mediante valores y porcentajes. Resultados: Un total de 361 pacientes respondieron al cuestionario (194 de China, 104 de España y 63 de Cuba). No encontramos ningún paciente chino con EM que hubiera padecido COVID-19, y los casos diagnosticados en España y Cuba fueron muy infrecuentes. A raíz de la pandemia, se observaron cambios en las relaciones con amigos, familiares y compañeros; además, los pacientes con EM usaron plataformas digitales y redes sociales con más frecuencia en los 3 países. El impacto negativo fue significativamente menor en España que en Cuba o China. Los efectos mentales y cognitivos de la pandemia fueron similares en los 3 países, aunque parece que la situación previa era mejor en China. Igualmente, observamos que el tiempo dedicado al ejercicio se redujo en momentos específicos durante la pandemia. Por el contrario, no se detectaron grandes cambios en los hábitos alimentarios. Los pacientes de los 3 países consideraron que no se produjeron cambios en su medio de transporte, o que estos fueron escasos. La mayoría de los pacientes ha experimentado poco o ningún deterioro físico, particularmente los pacientes chinos (82,47%) en comparación con los españoles (70,20%) y cubanos (73,02%). En líneas generales, todos los pacientes se mostraron esperanzados en superar la pandemia, aunque los pacientes españoles en menor grado. Conclusiones: Durante la pandemia, el apoyo familiar fue más importante en China que en Cuba o España. En ninguno de los 3 países se observó un aumento significativo en el número de casos de COVID-19 ni de brotes o recaídas durante el periodo de confinamiento. En términos económicos, los pacientes con EM españoles sufrieron un impacto negativo significativamente menor que los cubanos y chinos. Todos los pacientes usaron plataformas digitales o redes sociales con más frecuencia, probablemente con el fin de mantener relaciones personales. Los pacientes chinos y cubanos mostraron mayor confianza en el control de la pandemia que los españoles, que resultaron ser más pesimistas.

[Effects and mechanisms of allogeneic epidermal stem cells on the survival of allogeneic full-thickness skin grafts in nude mice with full-thickness skin defect wounds].

Objective: To investigate the effects and mechanisms of allogeneic epidermal stem cells (ESCs) on the survival of allogeneic full-thickness skin grafts in nude mice with full-thickness skin defect wounds. Methods: Experimental research methods were applied. Primary ESCs that appeared paving stone-like after being cultured for 7 d were obtained by enzymatic digestion method from one 4-week-old male BALB/c-NU nude mouse (the same strain, age, and sex below). The cells of third passage were identified by flow cytometry to positively express ESC marker CD44 and negatively express CD45, meanwhile, the positive expression of ESC markers of p63 and integrin 6α, and negative expression of CD71 were identified by immunofluorescence method. The ESCs of third passage in the logarithmic growth phase were used for the following experiments. Twenty-six nude mice were equally divided into phosphate buffered saline (PBS) group and ESCs group according to the random number table. A full-thickness skin defect wound was made on the back of each nude mouse, and then the wounds of the two groups were sprayed with equal volumes of PBS and ESCs, respectively. The wounds were transplanted with full-thickness skin grafts cut from the backs of 4 other nude mice. Each ten nude mice from the two groups were selected, the wound healing and skin survival on post surgery day (PSD) 0 (immediately), 3, 7, 14, and 21 were observed, and the survival ratio and shrinkage rate of skin grafts on PSD 3, 7, 14, and 21 were calculated (the number of sample was the number of surviving skin grafts at each time point); the blood perfusion in the skin grafts on PSD 3, 7, and 14 was detected by the laser speckle blood flow imager, and the blood flow ratio of nude mice skin grafts in ESCs group to PBS group at each time point was calculated (the number of sample was the pair number of surviving skin grafts in group pairing at each time point). The skin graft tissue of each 3 nude mice remained in the two groups were collected on PSD 7, and the mRNA expressions and protein expressions of tumor necrosis factor α (TNF-α), interleukin 8 (IL-8), IL-10, type Ⅰ collagen, type Ⅲ collagen, and matrix metalloproteinase 9 (MMP-9) in the tissue were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction and Western blotting, respectively. Data were statistically analyzed with Log-rank test, analysis of variance for repeated measurement, one-way analysis of variance, independent sample t test, and Bonferroni correction. Results: Taking the condition on PSD 0 as a reference, the wounds of nude mice in the two groups healed gradually on PSD 3, 7, 14, and 21, and the shrinkage of skin grafts was gradually obvious. Among them, the shrinkage healing of wound of nude mice in PBS group was more significant than that in ESCs group. On PSD 3, the skin graft of 1 nude mouse failed in ESCs group, while the skin graft of 3 nude mice failed in PBS group. On PSD 7, the skin graft of another nude mouse failed in PBS group. The survival ratio of skin grafts of nude mice in the two groups was similar on PSD 3, 7, 14, and 21 (P>0.05). On PSD 3, 7, 14, and 21, the shrinkage rates of skin grafts of nude mice in ESCs group were (9.2±0.4)%, (19.7±1.2)%, (53.6±3.5)%, and (62.2±5.1)%, respectively, which was significantly lower than (11.0±0.9)%, (47.8±2.8)%, (86.1±7.1)%, and (89.7±9.0)% in PBS group (t=5.719, 26.650, 11.940, 7.617, P<0.01). On PSD 3, 7, and 14, blood perfusion signals were observed in the skin grafts of nude mice in the two groups. The average blood perfusion ratios of the skin grafts of nude mice in ESCs group to PBS group were greater than 1, and there was no statistically significant difference in the overall comparison of 3 time points (P>0.05). On PSD 7, compared with those of PBS group, the mRNA and protein expressions of TNF-α, IL-8, type Ⅰ collagen, and type Ⅲ collagen in the skin graft tissue of nude mice in ESCs group were significantly reduced, while the mRNA and protein expressions of IL-10 and MMP-9 in the skin graft tissue of nude mice in ESCs group were significantly increased (in mRNA comparison, t=2.823, 2.934, 2.845, 2.860, 3.877, 2.916, P<0.05). Conclusions: Allogeneic ESCs can reduce the shrinkage of allogeneic full-thickness skin grafts transplanted on full-thickness skin defect wounds in nude mice, promote the formation of new blood vessels between the skin graft and the wound, reduce inflammation and collagen protein expression, and promote the expression of MMP-9, thus improving the survival quality of skin grafts.

Lightweight, strong, moldable wood via cell wall engineering as a sustainable structural material.

Wood is a sustainable structural material, but it cannot be easily shaped while maintaining its mechanical properties. We report a processing strategy that uses cell wall engineering to shape flat sheets of hardwood into versatile three-dimensional (3D) structures. After breaking down wood's lignin component and closing the vessels and fibers by evaporating water, we partially re-swell the wood in a rapid water-shock process that selectively opens the vessels. This forms a distinct wrinkled cell wall structure that allows the material to be folded and molded into desired shapes. The resulting 3D-molded wood is six times stronger than the starting wood and comparable to widely used lightweight materials such as aluminum alloys. This approach widens wood's potential as a structural material, with lower environmental impact for buildings and transportation applications.