Recycling solar-grade silicon from end-of-life photovoltaic modules by Al-Si solvent refining.

The development of the solar market has been fast in the past decades, and the number of photovoltaic module installations is large. The photovoltaic modules have a lifetime of about 25 years and need recovery after that. The aluminium-back surface field (Al-BSF) module is the first kind of large-scale installed module and will come to its end of life in the next few years. The recycling of silicon material in the Al-BSF module is investigated in this work. The components of the module are separated, and the silicon material in the module is collected and then purified by (aluminium-silicon) Al-Si solvent refining for reuse. It is found that Al-Si solvent refining removed key impurity elements, namely boron and phosphorus, in the collected silicon. Kinetics has a great effect on boron and phosphorus removal, and boron and phosphorus contents in purified silicon decrease with decreasing cooling rate. The boron and phosphorus contents in silicon are lowered to 0.28 and 0.03 ppmw, respectively, after two times of Al-Si solvent refining with the cooling rate of 5.55 * 10-4 K second-1, and it meets the requirement of solar-grade silicon.

Effects of combined sintilimab and chemotherapy on progression-free survival and overall survival in osteosarcoma patients with metastasis.

Objective: To explore the safety and efficacy of metastatic osteosarcoma treatment with combined sintilimab injection and chemotherapy. Methods: We performed a retrospective analysis of 32 patients with metastatic osteosarcoma admitted to the Affiliated Hospital of Beihua University between January 2019 and June 2020. The sample was divided into an observation group, treated with sintilimab injection combined with chemotherapy (n= 16) and a control group, treated with chemotherapy (n = 16). Clinical efficacy and adverse reactions were compared between the two groups. Results: The overall response rates were 68.75% in the observation group and 31.25% in the control group (p < 0.05). The incidences of adverse reactions were 56.25% in the observation group and 81.25% in the control group. This was not a significant difference. In the observation group, the progression-free survival time was 8.13 ± 2.50 months, and the overall survival time was 22.75 ± 4.95 months. These were both significantly longer than the respective 6.44 ± 1.93 months and 19.69 ± 2.68 months in the control group (p < 0.05). Conclusion: The treatment of metastatic osteosarcoma with combined sintilimab injection and chemotherapy was found to prolong progression-free survival and overall survival time without increasing the incidence of adverse reactions.

High Q-Factor Single-Mode Lasing in Inorganic Perovskite Microcavities with Microfocusing Field Confinement.

The realization of high-Q single-mode lasing on the microscale is significant for the advancement of on-chip integrated light sources. It remains a challenging trade-off between Q-factor enhancement and light-field localization to raise the lasing emission rate. Here, we fabricated a zero-dimensional perovskite microcavity integrated with a nondamage pressed microlens to three-dimensionally tailor the intracavity light field and demonstrated linearly and nonlinearly (two-photon) pumped lasing by this microfocusing configuration. Notably, the microlensing microcavity experimentally achieves a high Q-factor (16700), high polarization (99.6%), and high Purcell factor (11.40) single-mode lasing under high-repetition pulse pumping. Three-dimensional light-field confinement formed by the microlens and plate microcavity simultaneously reduces the mode volume (∼3.66 µm3) and suppresses diffraction and transverse walk-off loss, which induces discretization on energy-momentum dispersions and spatial electromagnetic-field distributions. The Q factor and Purcell factor of our lasing come out on top among most of the reported perovskite microcavities, paving a promising avenue toward further studying electrically driven on-chip microlasers.

Effects of the excitation wavelength and temperature on the zero-phonon emission line of Cr:YAG.

In this work, a detailed study was conducted of the temperature and excitation wavelength-dependent photoluminescence (PL) spectra of the chromium-doped yttrium aluminum garnet (Cr:YAG) transparent ceramic. Focusing on the two sets of zero-phonon lines (ZPLs) of the 2 E→4 A 2 transition in this material, the PL spectra are discovered to evolve significantly with respect to temperature and be highly dependent on the excitation wavelength. Compared to the continuous variation behavior with temperature, an increase in the excitation wavelength leads to a blueshift of the peak position within the regions of 450 nm to 465 nm, 465 nm to 490 nm, and 490 nm to 500 nm, and a sharp change in the PL position at the excitation wavelengths of 465 nm and 490 nm. The electron-phonon coupling (EPC) effect is believed to be more sensitive to the excitation wavelength. Different excitation wavelengths involve different electronic levels participating in the light emission processes, which explains the evolution behavior of the PL peak position with respect to the excitation wavelength. Moreover, the emergence of weak peaks next to the ZPLs at particular temperatures and excitation wavelengths is also observed. This work compares the influence of the temperature and excitation wavelength to the PL properties of the Cr:YAG transparent ceramic, which promotes an advanced understanding of the luminescence behavior of the Cr:YAG transparent ceramics.

Manipulation of Temperature-Dependent Luminescence Behaviors of Mn4+-Activated Fluoride Phosphors.

In this paper, the giant tunability of thermal behaviors, i.e., from thermal deterioration to substantial growth, is firmly demonstrated for the vibronic luminescence of Mn4+ ions in fluoride phosphors. Such peculiar behavior is uncovered to be associated with the thermal excitation of a low-frequency phonon bath, and a theoretical model involving the excitation-wavelength-dependent populations of vibronic levels and the temperature-dependent nonradiative recombination processes is successfully constructed. Two main governing parameters, namely, the thermal activation energy Ea and the involved average phonon energy ΔE, are thus determined for the distinct thermal behaviors of Mn4+-ion luminescence. This demonstration may pave the way for manipulating the thermal behaviors of vibronic luminescence in solids to some extent.

Research Advances in the Application of AI for Preoperative Measurements in Total Knee Arthroplasty.

Total knee arthroplasty (TKA) is widely used in clinical practice as an effective treatment for end-stage knee joint lesions. It can effectively correct joint deformities, relieve painful symptoms, and improve joint function. The reconstruction of lower extremity joint lines and soft tissue balance are important factors related to the durability of the implant; therefore, it is especially important to measure the joint lines and associated angles before TKA. In this article, we review the technological progress in the preoperative measurement of TKA.

A preliminary study of proximal realignment combination surgery in the treatment of adolescent habitual patellar dislocation.

OBJECTIVE: A combination of lateral soft tissue release, medial soft tissue contraction, vastus medialis anterior placement, medial patellofemoral ligament reconstruction, and rectus femoris insertion reconstruction are introduced in the treatment of habitual patellar dislocation in adolescents. METHODS: A retrospective analysis was performed on 12 patients (17 knees) with habitual patellar dislocation and unclosed epiphyses who underwent surgical treatment at the First Hospital of Jilin University from May 2017 to November 2021. The Lysholm scores and Q angle were collected preoperatively and at final follow-up and were compared. RESULTS: Twelve patients (4 boys and 8 girls) aged 10-15 years were retrospectively analysed, who followed up for an average of 21 months (5-48 months). The range of motion of the knee joint returned to normal in all patients, and no cases of complications including surgical site infection, joint stiffness, or patellar re-dislocation occurred. The mean Lysholm scores and Q angles improved from 73.9, and 19.6° preoperatively to 91.7, and 13.9° at the final follow-up, respectively. CONCLUSION: The preliminary effect of the combination surgery for habitual patellar dislocation in adolescents was satisfactory.

Modified treatment of knee osteoarthritis complicated with femoral varus deformity: A case report.

BACKGROUND: Surgical treatment of knee osteoarthritis (KOA) complicated by extra-articular deformity has always been controversial regardless of whether it is simultaneous or staged. Simultaneous total knee arthroplasty (TKA) combined with supracondylar osteotomy without plate for treatment of KOA complicated by femoral varus deformity has not been reported in the literature. CASE SUMMARY: A 53-year-old Chinese woman complained of left knee pain for 6 years that worsened for 4 mo during her visit on April 3, 2020, accompanied by instability in walking, which seriously affected quality of life. According to her medical history and preoperative imaging, the patient was diagnosed with left KOA with varus deformity. We used the angular center of rotation principle for osteotomy of the femur deformity and placed a poststabilized femur prosthesis into the knee joint. At the same time, a 13 mm × 130 mm femur extension rod was used instead of a steel plate to fix the end of the femur osteotomy, reducing the possible complications caused by steel plate implantation and reducing the economic burden on patients. The operation successfully solved two major problems of KOA and varus deformity, and the clinical and imaging evaluation of postoperative follow-up were satisfactory. CONCLUSION: TKA and supracondylar femoral osteotomy can be used for simultaneous KOA treatment and deformity correction.

Finite Element Analysis of a New Type of Spinal Protection Device for the Prevention and Treatment of Osteoporotic Vertebral Compression Fractures.

OBJECTIVE: To study the effectiveness of a new spinal protection device for preventing and treating osteoporotic vertebral compression fractures (OVCFs) by finite element analysis (FEA). METHODS: One healthy volunteer and one patient with 1-segment lumbar vertebral compression fractures were included in this experimental study. The DICOM files of two different lumbar spiral computed tomography (CT) scans were converted into STL files, and 3D finite element models of the lumbar spine were generated for normal and L1 vertebral fracture spines. A new type of spinal protection device was applied to reduce the stress on the anterior vertebral edge and direct the center of gravity posteriorly. The stress distribution characteristics of different finite element models of the lumbar spine were analyzed, revealing the characteristics of the stress distributed along the spine under the action of the new spinal protection device. RESULTS: Under normal conditions, the stress was mainly distributed in the middle and posterior columns of the spine. When the anterior border of the L1 vertebral body was fractured and collapsed, the stress distribution shifted toward the anterior column due to the center of gravity being directed forward. According to finite element analysis of the spine with the new protection device, the stress in the middle and posterior columns tended to increase, and that in the anterior column decreased. After the new type of spinal fixation device was applied, the stress at the L1 and L2 vertebral endplates decreased to a certain extent, especially that at the L1 vertebral body. The maximum stress on the L1 vertebral body decreased by 20% after the auxiliary device was applied. CONCLUSIONS: According to the FEA results, the new spinal protection device can effectively prevent and treat osteoporotic vertebral compression fractures (OVCFs), and can alter the stress distribution in the spine and reduce the stress in the anterior column of the vertebral body, especially in vertebral compression fractures.

The Effects of Tai Chi and Qigong Exercise on Psychological Status in Adolescents: A Systematic Review and Meta-Analysis.

Background: The purpose of this study was to systematically review the effectiveness of Tai Chi and Qigong exercise on adolescents' symptoms of depression and anxiety, and psychological status based on clinical evidences, and to calculate the pooled results using meta-analysis. Methods: A systematic search using seven English and three Chinese databases was initiated to identify randomized controlled trials (RCT) and non-randomized comparison studies (NRS) assessing the effect of Tai Chi and Qigong exercise on psychological status among adolescents. Standardized mean differences (SMD) and their 95% confidence intervals (CI) were used to determine the pooled effect of the intervention. Study quality was evaluated using a Checklist to Evaluate a Report of a Non-pharmacological Trial (CLEAR-NPT) designed for non-pharmacological trials. Results: Four RCTs and six NRS were identified, including 1,244 adolescents. The results suggested a potential beneficial effect of Tai chi and Qigong exercise on reducing anxiety (SMD = 0.386, 95 CI% [0.233, 0.538]) and depression (SMD = 1.937 [95 CI%, 1.392-2.546]) symptoms, and reducing cortisol level (SMD = 0.621 [95 CI%, 0.18-1.062]) in adolescents. Conversely, non-significant effects were found for stress, mood, and self-esteem. Conclusions: The findings of this review suggest Qigong appears to be an effective therapeutic modality to improve psychological well-being in adolescents. Hope future studies will have rigorously designed, well-controlled randomized trials with large sample sizes in order to confirm these findings.

Preparation of controlled degradation of insulin-like growth factor 1/spider silk protein nanofibrous membrane and its effect on endothelial progenitor cell viability.

The present study aimed to prepare a kind of controlled-releasing insulin-like growth factor 1 (IGF-1)/spider silk protein nanofibrous membrane using a electrostatic spinning method and evaluated its effect on the cell viability of endothelial progenitor cells (EPCs). Recombinant spidroin named as GMCDRSSP-IgF-1 was electro-spun into nanofibrous membrane which can be degraded by protease and be capable of sustained-release of IGF-1. The membrane can be degraded after being treated with thrombin. The release assay results showed that IGF-1 concentration could be maintained at 20 ng/ml for a long time with treatment of Tobacco Etch Virus (TEV) protease. The viability of EPCs on GMCDRSSP-IgF-1 nanofibrous membrane was significantly increased with the presence of TEV protease. The controlled and sustained release of IGF-1 from the nanofibrous membrane could promote the adhesion and viability of EPCs. In summary, the nanofibrous membrane that exhibits controlled degradation and sustained release of IGF-1 was prepared with electrostatic spinning from genetically modified recombinant spider silk protein. The nanofibrous membrane exhibited good blood compatibility and cytocompatibility. With the presence of TEV protease, the sustained-release of IGF-1 significantly promoted the adhesion and viability of EPCs. The new nanofibrous membrane can be potentially used as a scaffold for EPCs culture in vitro and future in vivo studies.

EPC-Derived Exosomal miR-1246 and miR-1290 Regulate Phenotypic Changes of Fibroblasts to Endothelial Cells to Exert Protective Effects on Myocardial Infarction by Targeting ELF5 and SP1.

Myocardial infarction (MI) remains a leading cause of morbidity and mortality worldwide. Endothelial progenitor cell (EPC)-derived exosomes have been found to be effective in alleviating MI, while the detailed mechanisms remain unclear. The present study aimed to determine the protective effects of EPC-derived exosomal miR-1246 and miR-1290 on MI-induced injury and to explore the underlying molecular mechanisms. The exosomes were extracted from EPCs; gene expression levels were determined by quantitative real-time PCR, and protein expression levels were determined by western blot and immunofluorescence staining, respectively. The angiogenesis and proliferation of human cardiac fibroblasts (HCFs) were determined by tube formation assay and immunofluorescence staining of PKH67, respectively. Luciferase reporter, CHIP, and EMSA assays determined the interaction between miR-1246/1290 and the targeted genes (EFL5 and SP1). The protective effects of miR-1246/1290 on MI were evaluated in a rat model of MI. EPC-derived exosomes significantly upregulated miR-1246 and miR-1290 expression and promoted phenotypic changes of fibroblasts to endothelial cells, angiogenesis, and proliferation in HCFs. Exosomes from EPCs with miR-1246 or miR-1290 mimics transfection promoted phenotypic changes of fibroblasts to endothelial cells and angiogenesis in HCFs, while exosomes from EPCs with miR-1246 or miR-1290 knockdown showed opposite effects in HCFs. Mechanistically, miR-1246 and miR-1290 from EPC-derived exosomes induced upregulation of ELF5 and SP1, respectively, by targeting the promoter regions of corresponding genes. Overexpression of both ELF5 and SP1 enhanced phenotypic changes of fibroblasts to endothelial cells and angiogenesis in HCFs pretreated with exosomes from EPCs with miR-1246 or miR-1290 mimics transfection, while knockdown of both EFL5 and SP1 exerted the opposite effects in HCFs. Both ELF5 and SP1 can bind to the promoter of CD31, leading to the upregulation of CD31 in HCFs. Furthermore, in vivo animal studies showed that exosomes from EPCs with miR-1246 or miR-1290 overexpression attenuated the MI-induced cardiac injury in the rats and caused an increase in ELF5, SP1, and CD31 expression, respectively, but suppressed α-SMA expression in the cardiac tissues. In conclusion, our study revealed that miR-1246 and miR-1290 in EPC-derived exosomes enhanced in vitro and in vivo angiogenesis in MI, and these improvements may be associated with amelioration of cardiac injury and cardiac fibrosis after MI.

Enhanced Optical Absorption in Perovskite/Si Tandem Solar Cells with Nanoholes Array.

Perovskite solar cells are used in silicon-based tandem solar cells due to their tunable band gap, high absorption coefficient and low preparation cost. However, the relatively large optical refractive index of bottom silicon, in comparison with that of top perovskite absorber layers, results in significant reflection losses in two-terminal devices. Therefore, light management is crucial to improve photocurrent absorption in the Si bottom cell. In this paper, nanoholes array filled with TiO2 is introduced into bottom cells design. By finite-difference time-domain methods, the absorption efficiency and photocurrent density in the range of 300-1100 nm has been analyzed, and the structural parameters have been also optimized. Our calculations show the photocurrent density which tends to be saturated with the increase in the height of the nanoholes. The absorption enhancement modes of photons at different wavelengths have been analyzed intuitively by the distribution of electric field. These results enable a viable and convenient route toward high efficiency design of perovskite/Si tandem solar cells.

Protrusion of a ceramic femoral head through the acetabular metallic cup in total-hip arthroplasty: A case report.

RATIONALE: Dislocation, wear, metallosis, and implant loosening are well-known complications of a failed total-hip arthroplasty (THA), and acetabular liner dissociation is an uncommon but catastrophic complication. To our knowledge, this is the first description of metallosis due to acetabular liner dissociation, but not presenting as a result of wear of a metal-on-metal articulation and a polyethylene liner of other articulation. PATIENT CONCERNS: We described a 61-year-old man who had a 2-year history of pain in the right groin region after THA. Postoperative period of primary THA was uneventful. However, he did not undergo postoperative follow-up, and often participated in strenuous sports activities including mountain climbing and long-distance running. DIAGNOSIS: Radiographs demonstrated superior subluxation of the femoral head and direct articulation and abrasion wear of the ceramic femoral head on the cup. Preoperative laboratory data revealed no signs of infection. INTERVENTIONS: We performed revision THA using a direct lateral approach with ceramic-on-ceramic hip prosthesis. OUTCOMES: Postoperatively, the patient wore a hip orthosis for 6 weeks to prevent dislocation but was allowed full weight bearing. At 1-year follow-up, there was no recurrence of hip pain. LESSONS: Wear of THA components can result in catastrophic failure of the implants and significant soft-tissue metallosis. Therefore, regular postoperative follow-up is necessary for early intervention, even in those with asymptomatic hips.

A genome-wide identification and analysis of basic helix-loop-helix transcription factors in cattle.

Basic helix-loop-helix (BHLH) transcription factors comprise a large family of regulatory proteins and play critical roles in the developmental processes of higher organisms. Complete lists of BHLH family members have been identified in about 50 organisms, including fruit fly, zebrafish, mouse, giant panda, worm, yeast, rice and apple. Cattle, Bos taurus, is important for agriculture and animal nutrition, and is also a good model organism for health research. In the present study, 116 putative BHLHs were identified in the cattle genome. Phylogenetic analyses revealed that 111 Bos taurus BHLH (BtBHLH: Bos taurus BHLH) members belong to 44 families, with 48, 26, 16, 4, 13 and 4 members in group A, B, C, D, E and F respectively, and the remaining 5 BtBHLHs are orphan members. All of them were named and assigned into the corresponding BHLH families based on acceptable bootstrap values from in-group phylogenetic analyses with orthologous BHLHs from mouse and other mammalian species. A comparison between annotations deposited in the GenBank and KEGG databases with our analyses indicated that the annotations of 2 of the 116 BtBHLH members were inconsistent with our analytical results. Microarray evidence and expressed sequence tags of only 14 BtBHLH genes was now not available. Chromosomal locations of the BtBHLHs showed that the distribution of the BtBHLHs was uneven and some genes, e.g., BtOligo, BtHes and BtMyf6, may arise from gene duplication. The test of positive selection showed episodic positive selection occurs only in 5 families among the studied mammalian BHLHs. These results provide a solid basis for further studies on BHLH protein regulation of key growth and developmental processes.

Virulence traits and pathogenicity of uropathogenic Escherichia coli isolates with common and uncommon O serotypes.

Urinary tract infections (UTIs) are among the most common human diseases worldwide. This study aimed to collect uropathogenic Escherichia coli (UPEC) isolates from Jiangsu Province and obtain insights into the molecular epidemiology of UPEC in this region. The O serotypes, phylogenetic groups, and virulence factors of 183 UPEC isolates were determined. In this study, we isolated 51 UPEC isolates with common O serotypes including O1, O2, O4, O6, O7, O16, O18 and O75, as well as 35 of those with uncommonly encountered O serotypes including O8, O12, O15, O26, and O74. Groups B2 and D were the most prevalent phylogenetic groups and accounted for 29.5% and 41% of the isolates, respectively. In the tested 13 virulence genes (VGs), tonB and dsdA possessed the highest prevalence rate, followed by fimH, degP and ompR. Several other virulence genes such as fliC, neuC, ireA, and vat had prevalence less than 23%. Moreover, representative isolates belonging to common or uncommon O serotypes with different numbers of VGs were chosen for the pathogenic analyses. Based on the results of 1-day-old chick lethality assay and UTI ascending mouse infection model, our study suggested that the virulence of UPEC isolates for chicks and/or mice depended on both the number of VGs expressed and the O serotypes.

[Particle impaction bone graft and plate internal fixation for the treatment of proximal femoral bone tumor or tumor lesion].

OBJECTIVE: To evaluate the clinical feasibility of particle impaction bone graft and plate internal fixation for the treatment of proximal femoral bone tumors or tumor disease. METHODS: From January 2013 to January 2016 a total of 26 cases of the proximal femur bone tumors or tumor lesions, neither pathological fracture, were retrospectively analyzed, including 12 males and 14 females with an average age of 34.2 years old ranging from 8 to 62 years old. The pathologic result involved fibrous dysplasia in 11 cases, bone isolation bone cyst in 7 cases, giant cell tumors of bone in 3 cases, aneurysm sample bone cyst in 3 cases, non ossifying fibroma in 1 case, benign fibrous histiocytoma in 1 case. No biopsy of the lesion was performed before the operation. Postoperative lesions were sent to pathology. The operation was treated by particle impaction bone graft and plate internal fixation. RESULTS: All patients were followed up to resume normal life for 8 to 42 months with an average of 25 months. The function assessment referenced to the bone and soft tissue tumor association (MSTS). At the end of the last examination, the positive and lateral X-ray films of the femur showed no low density shadow in the margin of bone graft and bone graft, and the bone healing in the bone graft area was good. No recurrence or metastasis was found in all patients, and no loosening or deformation of the internal fixator occurred. The hip function was well restored and no fracture or deformity progressed in all patients. CONCLUSIONS: The tumor recurrence in the proximal femur is related to curettage and bone grafting. After the curettage, the residual tumor cells were treated by chemical and physical methods. By this method, the disease can be cured for a long time, and it can reduce the recurrence and resume the function of the hip joint.