A new method for determining coordinates of the space TT&C radar rotation center based on GNSS.

The coordinate determination of the rotation center of a space TT&C (Telemetry, Tracking and Command) radar is an important task of radar-calibration. The conventional method mostly using total stations is expensive, inefficient, and faces technological limitations. This paper presents a new method of measuring the rotation center coordinates of TT&C radar equipment using GNSS (Global Navigation Satellite System) high precision positioning technology, providing the principle, mathematical model, and data processing algorithm of the new method. According to the exclusively-designed scheme, the new method has been fully tested and validated from both simulation & real-scene radar test. The test result and comparison show that the new method requires fewer equipment, fewer participants, and shorter working hours, with 60% efficiency improvement, compared to the traditional method. The accuracy of the new method could reach millimeter level, with 45% accuracy improvement over the traditional method. In summary, the results show that the new method not only offers higher efficiency and lower cost, but also expands the application method and scene of high-precise GNSS positioning in signal-challenging environment.

Comparative analysis of three-dimensional and two-dimensional models for predicting the malignancy probability of subsolid nodules.

AIM: To construct three-dimensional (3D) and two-dimensional (2D) models to predict the malignancy probability of subsolid nodules (SSNs) and compare their effectiveness. MATERIALS AND METHODS: A total of 371 SSNs from 332 patients, collected between January 2020 and January 2024, were included in the study. The SSNs were divided into a training set for constructing the models and a test set for validating the models. Models were developed using binary logistic backward regression, based on factors that showed significant differences in univariate analyses. The performance of the models was assessed using the area under the curve (AUC) of the receiver operating characteristic (ROC). The AUCs of different models were compared using the DeLong test. RESULTS: The AUCs for the two 3D models, one 2D model, and the Brock model were 0.785 (0.733-0.836), 0.776 (0.723-0.829), 0.764 (0.710-0.818), and 0.738 (0.679-0.798) in the training set. In the test set, these AUCs were 0.817 (0.706-0.928), 0.796 (0.679-0.913), 0.771 (0.647-0.895), and 0.790 (0.678-0.903). The two 3D models demonstrated statistically significant differences from the Brock model in the training set (P=0.024 and P=0.046). None of the four models showed significant differences in the test set (all P>0.05). CONCLUSION: The 3D models outperform both the 2D model and the Brock model in predicting the malignancy probability of SSNs, and the 3D model incorporating volume, mean CT attenuation value, and lobulation as factors performed the best.

Safety, Efficacy and Clinical Applications of Focused Ultrasound-Mediated Blood Brain Barrier Opening in Alzheimer's Disease: A Systematic Review.

Alzheimer's disease is a neurodegenerative disorder marked by cognitive decline and brain pathology involving amyloid plaques and neurofibrillary tangles. Current drug development focuses on disease-modifying therapies, primarily antibodies targeting amyloid or tau. However, the blood-brain barrier (BBB) poses a challenge for drug delivery to the brain. Pre- and early clinical data suggests that Focused Ultrasound (FUS) technology safely enhances BBB permeability without damaging brain tissue, enabling drug delivery. This systematic review discusses the application of FUS to open the BBB for the treatment of Alzheimer's disease (AD). We review the safety, efficacy, and potential biological effects of FUS-mediated BBB opening in AD patients.

[Efficacy analysis of letrozole combined with gonadotropin-releasing hormone antagonists in patients with high risk of ovarian hyperstimulation syndrome undergoing total embryo freezing].

Objective: To investigate the clinical efficacy of letrozole combined with gonadotropin-releasing hormone antagonists (GnRH-ant) in patients at high risk of ovarian hyperstimulation syndrome (OHSS) who underwent total embryo freezing after oocyte retrieval. Methods: A retrospective analysis was conducted on 348 female patients who underwent in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) at the Reproductive and Genetic Hospital of the First Affiliated Hospital of Zhengzhou University between January and July 2023. Due to their high risk of OHSS, these patients canceled fresh embryo transfer and opted for total embryo freezing. Based on patients' preferences, those who received GnRH-ant and letrozole after oocyte retrieval were categorized as the intervention group (164 cases), while those who did not receive these medications were categorized as the control group (184 cases). The first luteal phase after oocyte retrieval, OHSS grading, ovarian volume, and estradiol (E2) levels were evaluated in both groups. A multivariate logistic regression model was used to analyze factors related to moderate-to-severe OHSS among patients at high risk of OHSS who underwent total embryo freezing after oocyte retrieval. Results: The age of the intervention and control groups was (29.3±3.8) and (29.4±4.1) years, respectively (P=0.821). The duration of the first luteal phase post-oocyte retrieval was shorter in the intervention group [(7.16±1.39) days] compared to that in the control group [(13.88±2.11) days] (P<0.001). The incidences of mild, moderate, and severe OHSS in the intervention group were 75.0% (123 cases), 23.8% (39 cases), and 1.2% (2 cases), respectively, whereas in the control group they were 12.5% (23 cases), 60.9% (112 cases), and 26.6% (49 cases) (P<0.001). E2 levels on the 2nd and 6th days after oocyte retrieval [M(Q1,Q3)] in the intervention group were 1 520.0 (1 213.8, 1 884.8) and 108.5 (45.6, 218.0) ng/L, respectively, which were statistically significantly lower than those in the control group [1 666.0 (508.8, 1 702.0) ng/L] and [1 761.0 (826.0, 2 546.5) ng/L] (P<0.001). The abdominal cavity effusion in the intervention group [M(Q1,Q3)] were 19.5 (0, 30) and 0 mm, statistically significantly less than those in the control group [46.0 (0, 61.0) mm] and [54.5 (0, 69.5) mm] (P<0.001). On the 6th day after oocyte retrieval, the bilateral ovarian volumes in the intervention group were smaller than those in the control group (P<0.001). Multivariate logistic regression analysis indicated that no combined treatment with letrozole and GnRH-ant was a risk factor of moderate to severe OHSS. The risk of developing moderate to severe OHSS in the control group was 35.312 times higher than that in the intervention group (OR=35.312, 95%CI: 17.488-71.300). Conclusions: The administration of letrozole combined with GnRH-ant post-oocyte retrieval in patients at high risk of OHSS can prevent the occurrence of moderate-to-severe OHSS, shorten the first luteal phase, accelerate the reduction of serum E2 levels, and promote the recovery of ovarian volume and absorption of abdominal fluid.

[Coenzyme Q10 alleviates depression-like behaviors in mice with chronic restraint stress by down-regulating the pyroptosis signaling pathway].

OBJECTIVE: To explore the neuroprotective effect of coenzyme Q10 and its possible mechanism in mice with chronic restraint stress (CRS). METHODS: Mouse models of CRS were treated with intraperitoneal injections of coenzyme Q10 at low, moderate and high doses (50, 100 and 200 mg/kg, respectively, n=8), VX765 (a caspase-1 specific inhibitor, 50 mg/kg, n=8), or fluoxetine (10 mg/kg, n=8) on a daily basis for 4 weeks, and the changes in depression-like behaviors of the mice were assessed by sugar water preference test, forced swimming test and tail suspension test. The expression of glial fibrillary acidic protein (GFAP) in the hippocampus of the mice was detected using immunohistochemistry, and the number of synaptic spines was determined with Golgi staining. Western blotting was performed to detect the changes in the expressions of GFAP and pyroptosis-related proteins in the hippocampus, and the colocalization of neurons and caspase-1 p10 was examined with immunofluorescence assay. RESULTS: Compared with the normal control mice, the mouse models of CRS showed significantly reduced sugar water preference and increased immobility time in forced swimming and tail suspension tests (P < 0.05), and these depression-like behaviors were obviously improved by treatment with coenzyme Q10, VX765 or FLX. The mouse models showed a significantly decreased positive rate of GFAP and lowered GFAP protein expression in the hippocampus with obviously decreased synaptic spines, enhanced expressions of GSDMD-N, caspase-1 and IL-1ß, and increased colocalization of neurons and caspase-1 p10 (all P < 0.05). All these changes were significantly ameliorated in the mouse models after treatment with Q10. CONCLUSION: Coenzyme Q10 can alleviate depression-like behaviors in mice with CRS by down-regulating the pyroptosis signaling pathway.

Effects of Three Different Heating Devices on Patients Undergoing Surgery: A Network Meta-Analysis.

PURPOSE: Perioperative hypothermia is a common anesthesia-related complication that can result in negative outcomes. Intraoperative active heating can positively impact these outcomes. Therefore this study aimed to investigate the effectiveness of three common heating devices for controlling hypothermia, improving thermal comfort, and reducing anesthesia recovery time. DESIGN: Systematic review and meta-analysis. METHODS: Seven electronic literature databases were searched from the inception date of the databases to March 18, 2022. RevMan 5.4 and Stata 15.1 were used to perform meta-analyses on the obtained data, and the Cochrane Evaluation Manual was used for quality risk assessment of the included studies. FINDINGS: A total of 18 studies involving 1,511 patients undergoing surgery using heating devices were included. In this meta-analysis, a ranking method known as the Surface Under the Cumulative Ranking Curve (SUCRA) was used. SUCRA provides a numerical measure of the effectiveness of treatments, with higher values indicating superior efficacy. Findings demonstrated that the concurrent use of three heating devices led to an elevation in core body temperatures (SUCRA = 69.2%) and enhanced delayed recovery (SUCRA = 88.6%) as compared to the application of a single device. Furthermore, for thermal comfort, the employment of heating blankets proved to be the most effective (SUCRA = 87.8%). CONCLUSIONS: This study showed the core body temperatures and reductions in delayed recovery were greater when three heating devices were used together as compared to use one of them alone. Heating blankets was the most effective option for improving the thermal comfort of patients. Thus, clinicians should opt for appropriate heating equipment according to the type of surgery and the characteristics and needs of patients. The choice of appropriate heating equipment will ensure surgical safety, improve patient comfort, and reduce surgical risks.

DNA Repair Genetics and the Risk of Radiation Pneumonitis in Patients With Lung Cancer: A Systematic Review and Meta-analysis.

AIMS: ERCC1 rs11615 and ERCC2 rs238406 single nuclear polymorphism (SNPs) are known for their association with treatment outcome, likely related to radiosensitivity of both tumor and normal tissue in patients with non-small-cell lung cancer. This study aimed to review the effect of 1) these ERCC1/2 SNPs and 2) other SNPs of DNA repair genes on radiation pneumonitis (RP) in patients with lung cancer. MATERIALS AND METHODS: SNPs of our interest included ERCC1 rs11615 and ERCC2 rs238406 and other genes of DNA repair pathways that are functional and biologically active. DNA repair SNPs reported by at least two independent studies were pooled for meta-analysis. The study endpoint was radiation pneumonitis (RP) after radiotherapy. Recessive, dominant, homozygous, heterozygous, and allelic genotype models were used where appropriate. RESULTS: A total of 16 studies (3080 patients) were identified from the systematic review and 12 studies (2090 patients) on 11 SNPs were included in the meta-analysis. The SNPs were ATM rs189037, ATM rs373759, NEIL1 rs4462560, NEIL1 rs7402844, APE1 rs1130409, XRCC3 rs861539, ERCC1 rs11615, ERCC1 rs3212986, ERCC2 rs238406, ERCC2 rs13181, and XRCC1 rs25487. ERCC1 rs11615 (236 patients) and ERCC2 rs238406 (254 patients) were not significantly associated with RP. Using the allelic model, the G allele for NEIL1 gene was significantly associated with a reduced odds of developing symptomatic (grade ≥2) RP compared to the C allele for rs7402844 (OR 0.70, 95% CI: 0.49, 0.99, P = 0.04). Similarly, the T allele for APE1 gene was significantly associated with a reduced odds of developing symptomatic (grade ≥2) RP compared to the G allele for rs1130409 (OR 0.59, 95% CI: 0.43, 0.81, P = 0.001). CONCLUSION: Genetic variation in the DNA repair pathway genes may play a significant role in the risk of developing radiation pneumonitis in patients with lung cancer. Further studies are needed on genotypic features of DNA repair pathway genes and their association with treatment sensitivity, as such knowledge may guide personalized radiation dose prescription.

[Preliminary observation of wearable balance diagnosis and treatment system in evaluating dynamic and static balance function in patients with vestibular vertigo].

A newly developed wearable balance diagnosis and treatment system was studied to evaluate the indexes of the abnormal balance function in patients with vestibular vertigo. A cross-sectional study was carried out. A total of 30 patients diagnosed with non-acute vestibular vertigo in the outpatient department of Eye, Ear, Nose and Throat Hospital Affiliated to Fudan University from July 2022 to May 2023 were selected as the vertigo group, including 13 males and 17 females, and aged (45.7±13.9) years. Meanwhile, 20 healthy controls (8 males and 12 females) were included as the control group, with a mean age of (43.6±8.0) years. The static balance and limits of stability (LOS) function of all subjects were assessed with wearable balance diagnosis and treatment system developed under the leadership of Eye & ENT Hospital of Fudan University. In the static balance test, the ratio of eyes open with cushions to eyes open without cushions in the vertigo group was less than that of the control group[1.20% (0.92%, 1.53%) vs 1.49% (1.22%, 1.81%), P=0.008], indicating that patients with non-acute vestibular vertigo may compensate static balance ability earlier. In vertigo group, the directional control in 8 directions, the maximum excursion in anterior, posterior, right anterior and right posterior directions, the endpoint excursion in the posterior, right posterior, and left posterior directions were all smaller than those of the control group (all P<0.05). The reaction time in the left posterior direction of vertigo group was longer than that of the control group (all P<0.05). Those results indicated that the directional control, maximum excursion and endpoint excursion of LOS could be considered as important reference indexes for dynamic balance function.

Cytomegalovirus Infection and Alzheimer's Disease: A Meta-Analysis.

BACKGROUND: Evidence on the association of cytomegalovirus (CMV) infection with Alzheimer's disease (AD) is scarce and the results are inconsistent. OBJECTIVE: To investigate the association of CMV infection with the risk of AD. METHODS: Observational studies on the relationship between CMV infection and AD were identified from PubMed, Embase, Web of Science, and the Cochrane Library until September 30, 2022. The quality of included studies was assessed using the Newcastle-Ottawa Scale. Random-effect meta-analysis was performed using a generic inverse-variance method, followed by sensitivity analyses and subgroup analyses based on study designs, regions, adjustments, and population types. RESULTS: Our search yielded 870 articles, of which 200 were duplicates and 663 did not meet the inclusion criteria, and finally yielded seven studies with 6,772 participants. No strong evidence was observed in the summary analysis for the association of CMV infection and risk of AD (odds ratio [OR] = 1.33; 95% confidence interval [CI]: 0.88, 2.03, I2 =69.9%). However, subgroup analysis showed that an increased risk of AD was detected in East Asians (OR = 2.39; 95% CI: 1.63, 3.50, I2 = 0.00%), cohort studies (OR = 1.99; 95% CI: 1.35, 2.94, I2 = 28.20%), and studies with confounder adjustment (OR = 2.05; 95% CI: 1.52, 2.77, I2 = 0.00%). CONCLUSIONS: This meta-analysis provides evidence to support the heterogeneity of the associations between CMV infection and AD. Future studies with larger sample sizes and multi-ethnic populations are necessary.

[Clinical effect of free posterior interosseous artery perforator flap carrying superficial vein for reconstructing severe perioral scar hyperplasia and contracture].

Objective: To observe the clinical effect of free posterior interosseous artery perforator flap carrying superficial vein for reconstructing severe perioral scar hyperplasia and contracture. Methods: The retrospective observational study method was used. From August 2019 to March 2023, 11 patients with severe perioral scar hyperplasia and contracture after severe facial burns who met the inclusion criteria were admitted to General Hospital of TISCO (the Sixth Hospital of Shanxi Medical University). All patients were male and aged 23 to 56 years, with an average age of 31.3 years. After the perioral scar was removed and released, the wound area was 3.0 cm×2.0 cm to 10.5 cm×2.0 cm. The free posterior interosseous artery perforator flap carrying superficial vein was used to repair the wound, and the flap incision area was 3.5 cm×2.5 cm to 11.0 cm×2.5 cm. Among them, 6 patients required repair of wounds after resecting scar around ipsilateral upper and lower lips, and the lobular treatment of the flap was conducted. The wound in the flap donor area was directly sutured. After surgery, the survival of the flap and the occurrence of vascular crisis were observed. During follow-up after surgery, the appearance, texture, and color of the flap, the appearance of the flap donor area, and improvements of crooked mouth, drooling, limited mouth opening, and lip valgus in patients were observed. Results: All the flaps in patients completely survived after surgery, with no occurrence of vascular crisis. During follow-up of 6 to 36 months after surgery, the flap was not significantly bloated, was soft in texture, and had a similar color to that of the normal facial skin. Only linear scars were left in the flap donor area, and crooked mouth, drooling, limited mouth opening, and lip valgus in patients were significantly improved. Conclusions: The free posterior interosseous artery perforator flap carrying superficial vein can reconstruct severe perioral scar hyperplasia and contracture, with low incidence of postoperative flap vascular crisis, and the lobular treatment of flaps can repair wounds around unilateral upper and lower lips at the same time. After surgery, the appearance and function of the perioral area are significantly improved. The flap is a good choice for repairing small area of severe perioral scar hyperplasia and contracture.

Study on stability of formation for gravity field exploration subjected to disturbance based on prescribed performance control.

Double satellite formation for gravity field exploration is a complex space virtual instrument system with high-precision, whose normal manner is threatened by the space debris environment. The normal manner of the formation based on control with prescribed performance is studied. Based on the random impact of space debris, nonlinear dynamical equations with 20 variables are established considering the relative attitude of the double satellite. The interferential characteristics and expected stability under certain disturbance conditions by the space debris in low Earth orbit are analyzed. To simplify the relative motion of the formation and the motion of the test mass (TM) relative to the cage, a prescribed performance function is introduced to constrain the relative attitude errors of transient and steady states. An adaptive attitude control design method based on a prescribed performance function is proposed. Finally, the analysis is carried out. The results show that the probability of normal manner of the formation is about 78.45% in the first year and about 45.59% in the first three years. The normal manner of the double satellite formation for gravity field exploration can be effectively simulated and analyzed based on the prescribed performance control methods.

[Effects of low position lateral supramalleolar flap carrying periosteum and proximal leg propeller flap in relay repair of electric burn wounds of forefoot].

Objective: To explore the effects of low position lateral supramalleolar flap carrying periosteum and proximal leg propeller flap in relay repair of electric burn wounds of forefoot. Methods: A retrospective observational study was conducted. From January 2019 to January 2022, 12 patients with electric burn wounds of forefoot meeting the inclusion criteria were admitted to the Sixth Hospital of Shanxi Medical University, including 10 males and 2 females, aged 23-65 years. After debridement, the wound with an area of 6.0 cm×3.0 cm to 15.0 cm×7.0 cm was repaired with the lateral supramalleolar flap carrying part of the periosteum of the distal tibia and fibula with the rotation point moved down to the front of the ankle joint. The area of the cutted flap was 6.5 cm×3.5 cm-15.5 cm×7.5 cm. At the same stage, the donor site wound of lateral supramalleolar flap was repaired with peroneal artery or superficial peroneal artery perforator propeller flap in relay, with the relay flap area of 3.0 cm×1.5 cm-15.0 cm×4.0 cm. After operation, the survival of the lateral supramalleolar flap and relay flap, and the wound healing of the relay flap donor site were observed. During follow-up, the shapes of the lateral supramalleolar flap and its donor site were observed. Results: After operation, one patient developed secondary blisters in the superficial skin distal to the lateral supramalleolar flap, which healed after dressing change, and the lateral supramalleolar flap and relay flaps survived well in the other patients; the donor site wound of the relay flap healed well. During follow-up of 12-18 months, the lateral supramalleolar flaps were in good shape and not bloated, with only linear scar left in the donor site of the flap. Conclusions: The low position lateral supramalleolar flap carrying periosteum can repair electric burn wounds of forefoot with advantages including reliable blood supply, low rotation point, and better repair effects. The use of relay flap to repair the donor site of lateral supramalleolar flap can reduce the damage to the appearance and function of the donor site.

[Current status and update of infantile hemangioma in diagnosis and therapy].

Infantile hemangiomas (IHs) are benign vascular tumors commonly observed in children. It is important to familiar with the characteristic features of hemangioma before diagnosis. Lesions located special position including periorbital and beard region, segmental hemangioma related PHACE syndrome and LUMBAR syndrome, hepatic hemangioma and related possible risks should be recognized. Early evaluation and assessment of risk grades should be done as early as possible before proliferation phase, so as to choosing the optimal treatment opportunity and scheme. ß-blockers are the mainstay of therapy for moderate-to-high risk hemangiomas nowadays. Early initiation of treatment can prevent adverse complications and achieve the best outcome. During the diagnosis and treatment of infantile hemangioma, it emphasizes updating of the concept of naming and classification, treatment timing control and therapeutic scheme selection. Standardized clinical diagnosis and treatment should be promoted currently.

Predictive value of total ischaemic time and T1 mapping after emergency percutaneous coronary intervention in acute ST-segment elevation myocardial infarction.

AIM: To investigate the predictive value of ischaemic time and cardiac magnetic resonance imaging (CMRI) T1 mapping in acute ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI). MATERIALS AND METHODS: A total of 127 patients with STEMI treated by primary PCI were studied. All patients underwent CMRI with native T1 and extracellular volume (ECV) measurement, 61 of whom also had 4-month follow-up data. The total ischaemic (symptom onset to balloon, S2B) time expressed in minutes was recorded. CMRI cine, T1 mapping, and late gadolinium enhancement (LGE) images were analysed to evaluate left ventricular (LV) function, T1 value, ECV, and myocardial infract (MI) scar characteristics, respectively. The correlation between S2B time and T1 mapping was evaluated. The predictive values of S2B time and T1 mapping for large final infarct size were estimated. RESULTS: The incidence of microvascular obstruction (MVO) increased with the prolongation of ischaemia time. Regardless of MVO or not, ECV in myocardial infarction (ECVMI) was significantly correlated with S2B time (r=0.61, p<0.001), while native T1 in MI (T1MI) was not (r=-0.19, p=0.029). In the 4-month follow-up, native T1MI was improved (1385.1 ± 90.4 versus 1288.6 ± 74 ms, p<0.001). Furthermore, ECVMI was independently associated with final larger infarct size (AUC = 0.89, 95% confidence interval [CI] = 0.81-0.98, p<0.001) in multivariable regression analysis. CONCLUSION: ECVMI was correlated with total ischaemic time and was an independent predictor of final larger infarct size.

["Double Grooves-Double Rings" technique of transurethral Thulium laser enucleation of the prostate: learning curve of single surgeon].

Objective: To evaluate the learning curve of the "Double Grooves-Double Rings" (DGDR) technique of transurethral Thulium laser enucleation of the prostate (ThuLEP) for benign prostatic hyperplasia (BPH) by a single surgeon. From June 2021 to July 2022, 84 patients mean age (69.0±8.0) years,preoperative prostate volume (90.9±40.3)ml with BPH underwent ThuLEP in the Department of Urology, Peking University First Hospital.Performed by a single surgeon who had no experience of transurethral resection of prostate (TURP) and any laser surgeries. The case scatter plots with the best fitting line were drawn to analyze the learning curve. According to the date of the surgeries, the patients were equally divided into three learning stages (28 patients for each group). The T-PSA,prostate volume,operative time,enucleation time, enucleation efficiency,catheter indwelling time, hemoglobin drop and perioperative complications (including re-TURP, blood transfusion, stress incontinence≥3 months and urethral stricture) were compared among the groups. The learning curve was divided into three stages, and the cutting point was shown on the 14th case. Except the prostate volume [stage1 (75.7±30.7) ml, stage2 (93.40±39.6)ml, stage3 (103.5±46.2) ml, P<0.05], there was no significant difference of the baseline data between three groups (P>0.05). Compared with those of stage 1(100.6±24.7) min,(0.55±0.22) g/min, a statistically significant improvement was observed in both of the operative time and the enucleation efficiency among stage 2[(84.5±36.6) min, (0.87±0.33) g/min and stage 3 (71.2±26.3) min, (1.27±0.45) g/min, P<0.05]. The learning curve of the DGDR technique for ThuLEP can be divided into three stages. A ThuLEP beginner can preliminarily master this technique after completing 14 cases.

[The application value of deep learning image reconstruction on improving image quality and evaluating the Qanadli embolism index of dual low-dose CT pulmonary angiography].

Objective: To compare the image quality and Qanadli embolism index between deep learning image reconstruction (DLR) and adaptive statistical iterative reconstruction-veo (ASiR-V) in dual low-dose CT pulmonary angiography (CTPA) with low contrast agent dose and low radiation dose. Methods: Eighty-eight patients who underwent dual low-dose CTPA in the radiology department of the affiliated hospital of Xuzhou Medical University from October 2020 to March 2021 were retrospectively analyzed, including 44 males and 44 females, aged from 11 to 87 years (61±15 years). The CTPA examination were performed using 80 kV tube voltage and 20 ml contrast agent. The raw data were reconstructed using standard kernel DLR high level (DL-H) and ASiR-V reconstruction, respectively. The patients were divided into standard kernel DL-H group (n=88, 33 cases of positive embolism) and ASiR-V group (n=88, 36 cases of positive embolism). The CT value, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), subjective image quality score, Qanadli embolism index, positive rate and positive Qanadli embolism index were compared between the two groups. Results: There were no statistically significant differences in CT values of the main pulmonary artery, the right pulmonary artery and the left pulmonary artery between the standard kernel DL-H group and ASiR-V group [(405.8±111.7) vs (404.0±112.0) HU, (412.9±113.1) vs (411.5±112.2) HU, (418.1±119.9) vs (415.4±118.0) HU, respectively;all P>0.05)]. The image noise of the main pulmonary artery, the right pulmonary artery and the left pulmonary artery in the standard kernel DL-H group was significantly lower than the ASiR-V group(16.6±4.7 vs 28.1±4.8, 18.3±6.1 vs 29.8±4.9, 17.6±5.6 vs 28.4±4.7, respectively;all P<0.001). The SNR and CNR of the main pulmonary artery, the right pulmonary artery and the left pulmonary artery in the standard kernel DL-H group were significantly higher than the ASiR-V group(SNR: 25.5±7.1 vs 14.5±3.9, 23.9±7.2 vs 13.9±3.4, 24.9±7.4 vs 14.8±4.1, CNR: 21.6±6.6 vs 12.3±3.9, 20.2±6.7 vs 11.8±3.4, 21.2±6.9 vs 12.6±4.1, respectively;all P<0.001). The subjective image quality score of the standard kernel DL-H group was significantly higher than the ASiR-V group (4.6 vs 3.8, P<0.001). There were no significant difference in the Qanadli embolism index, positive rate and positive Qanadli embolism index between the two groups (all P>0.05). Conclusion: Compared with ASiR-V reconstruction algorithms group, standard kernel DL-H reconstruction algorithms can significantly improve the image quality of dual low-dose CTPA.

Mapping the 3D position of battery cathode particles in Bragg coherent diffractive imaging.

In Bragg coherent diffractive imaging, the precise location of the measured crystals in the interior of the sample is usually missing. Obtaining this information would help the study of the spatially dependent behavior of particles in the bulk of inhomogeneous samples, such as extra-thick battery cathodes. This work presents an approach to determine the 3D position of particles by precisely aligning them at the instrument axis of rotation. In the test experiment reported here, with a 60 µm-thick LiNi0.5Mn1.5O4 battery cathode, the particles were located with a precision of 20 µm in the out-of-plane direction, and the in-plane coordinates were determined with a precision of 1 µm.