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1.
Nan Fang Yi Ke Da Xue Xue Bao ; 44(4): 660-665, 2024 Apr 20.
Article in Chinese | MEDLINE | ID: mdl-38708498

ABSTRACT

OBJECTIVE: To investigate the effects of different ventilation strategies on intraocular pressure (IOP) and intracranial pressure in patients undergoing spinal surgery in the prone position under general anesthesia. METHODS: Seventy-two patients undergoing prone spinal surgery under general anesthesia between November, 2022 and June, 2023 were equally randomized into two groups to receive routine ventilation (with Vt of 8mL/kg, Fr of 12-15/min, and etCO2 maintained at 35-40 mmHg) or small tidal volume hyperventilation (Vt of 6 mL/kg, Fr of18-20/min, and etCO2 maintained at 30-35 mmHg) during the surgery. IOP of both eyes (measured with a handheld tonometer), optic nerve sheath diameter (ONSD; measured at 3 mm behind the eyeball with bedside real-time ultrasound), circulatory and respiratory parameters of the patients were recorded before anesthesia (T0), immediately after anesthesia induction (T1), immediately after prone positioning (T2), at 2 h during operation (T3), immediately after supine positioning after surgery (T4) and 30 min after the operation (T5). RESULTS: Compared with those at T1, IOP and ONSD in both groups increased significantly at T3 and T4(P < 0.05). IOP was significantly lower in hyperventilation group than in routine ventilation group at T3 and T4(P < 0.05), and ONSD was significantly lower in hyperventilation group at T4(P < 0.05). IOP was positively correlated with the length of operative time (r=0.779, P < 0.001) and inversely with intraoperative etCO2 at T3(r=-0.248, P < 0.001) and T4(r=-0.251, P < 0.001).ONSD was correlated only with operation time (r=0.561, P < 0.05) and not with IOP (r=0.178, P>0.05 at T3; r=0.165, P>0.05 at T4). CONCLUSION: Small tidal volume hyperventilation can relieve the increase of IOP and ONSD during prone spinal surgery under general anesthesia.


Subject(s)
Anesthesia, General , Hyperventilation , Intraocular Pressure , Tidal Volume , Humans , Prone Position , Intraocular Pressure/physiology , Anesthesia, General/methods , Intracranial Pressure , Spine/surgery , Female , Male , Respiration, Artificial/methods , Intracranial Hypertension/surgery , Intracranial Hypertension/etiology
2.
Rev Sci Instrum ; 95(5)2024 May 01.
Article in English | MEDLINE | ID: mdl-38758767

ABSTRACT

As the plasma beta (ß) increases in high-performance tokamaks, electromagnetic turbulence becomes more significant, potentially constraining their operational range. To investigate this turbulence, a cross-polarization scattering (CPS) diagnostic system is being developed on the HL-3 tokamak for simultaneous measurements of density and magnetic fluctuations. In this work, a quasi-optical system has been designed and analyzed for the Q-band CPS diagnostic. The system includes a lens group for beam waist size optimization, a rotatable wire-grid polarizer for polarization adjustment, and a reflector group for measurement range regulation and system response enhancement. Laboratory tests demonstrated a beam radius of order 4 cm at the target measurement location (near the plasma pedestal), cross-polarization isolation exceeding 30 dB, and poloidal and toroidal angle adjustment ranges of ±40° and ±15°, respectively. These results verify the system's feasibility through laboratory evaluations. The quasi-optical system has been installed on the HL-3 tokamak during the 2023 experimental campaign to support the development of CPS diagnostics.

3.
iScience ; 27(2): 108800, 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38292430

ABSTRACT

Alzheimer's disease (AD) is associated with both extracellular amyloid-ß (Aß) plaques and intracellular tau-containing neurofibrillary tangles (NFT). We characterized the behavioral, metabolic and lipidomic phenotype of the 5xFADxTg30 mouse model which contains overexpression of both Aß and tau. Our results independently reproduce several phenotypic traits described previously for this model, while providing additional characterization. This model develops many aspects associated with AD including frailty, decreased survival, initiation of aspects of cognitive decline and alterations to specific lipid classes and molecular lipid species in the plasma and brain. Notably, some sex-specific differences exist in this model and motor impairment with aging in this model does compromise the utility of the model for some movement-based behavioral assessments of cognitive function. These findings provide a reference for individuals interested in using this model to understand the pathology associated with elevated Aß and tau or for testing potential therapeutics for the treatment of AD.

5.
Zhonghua Xue Ye Xue Za Zhi ; 44(10): 813-819, 2023 Oct 14.
Article in Chinese | MEDLINE | ID: mdl-38049332

ABSTRACT

Objective: To further elucidate the clinical efficacy and safety of a combination regimen based on the BTK inhibitor zebutanil bridging CD19 Chimeric antigen receptor T cells (CAR-T cells) in the treatment of relapsed/refractory diffuse large B-cell lymphoma (r/r DLBCL) . Methods: Twenty-one patients with high-risk r/r DLBCL were treated with a zanubrutinib-based regimen bridging CAR-T between June 2020 and June 2023 at the Department of Hematology, Tongji Hospital, Tongji University and the Second Affiliated Hospital of Zhejiang University, and the efficacy and safety were retrospectively analyzed. Results: All 21 patients were enrolled, and the median age was 57 years (range: 38-76). Fourteen patients (66.7%) had an eastern cooperative oncology group performance status score (ECOG score) of ≥2. Eighteen patients (85.7%) had an international prognostic index (IPI) score of ≥3. Three patients (14.3%) had an IPI score of 2 but had extranodal infiltration. Fourteen patients (66.7%) had double-expression of DLBCL and seven (33.3%) had TP53 mutations. With a median follow-up of 24.8 (95% CI 17.0-31.6) months, the objective response rate was 81.0%, and 11 patients (52.4%) achieved complete remission. The median progression-free survival (PFS) was 12.8 months, and the median overall survival (OS) was not reached. The 1-year PFS rate was 52.4% (95% CI 29.8% -74.3%), and the 1-year OS rate was 80.1% (95% CI 58.1% -94.6%). Moreover, 18 patients (85.7%) had grade 1-2 cytokine-release syndrome, and two patients (9.5%) had grade 1 immune effector cell-associated neurotoxicity syndrome. Conclusion: Zanubrutinib-based combination bridging regimen of CAR-T therapy for r/r DLBCL has high efficacy and demonstrated a good safety profile.


Subject(s)
Lymphoma, Large B-Cell, Diffuse , Receptors, Chimeric Antigen , Humans , Middle Aged , Receptors, Chimeric Antigen/therapeutic use , Retrospective Studies , Immunotherapy, Adoptive/adverse effects , Lymphoma, Large B-Cell, Diffuse/drug therapy , Cell- and Tissue-Based Therapy , Antigens, CD19/adverse effects
6.
Rev Sci Instrum ; 94(9)2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37668510

ABSTRACT

A 105 GHz collective Thomson scattering (CTS) diagnostic has been successfully developed for fast-ion measurements on the HL-2A tokamak, and it has been deployed during an experimental campaign. Enhanced signals exhibiting synchronous modulation characteristics have been observed across all CTS channels upon the launch of a modulated probe wave. Results show that the intensity of the CTS signal increases with Neutral Beam Injection (NBI) power and is proportional to neutron count, indicating that the scattering signal contains a contribution from fast ions. Compared with the signal without NBI, the enhanced scattering spectrum due to NBI is slightly wider than the predicted fast ion range. Such broadening might be attributed to the heating effects of the gyrotron.

8.
Sci Rep ; 13(1): 4785, 2023 Mar 23.
Article in English | MEDLINE | ID: mdl-36959269

ABSTRACT

The evolutions of MHD instability behaviors and enhancement of both electrostatic and electromagnetic turbulence towards the plasma disruption have been clearly observed in the HL-2A plasmas. Two types of plasma disruptive discharges have been investigated for similar equilibrium parameters: one with a distinct stage of a small central temperature collapse ([Formula: see text] 5-10%) around 1 millisecond before the thermal quench (TQ), while the other without. For both types, the TQ phase is preceded by a rotating 2/1 tearing mode, and it is the development of the cold bubble from the inner region of the 2/1 island O-point along with its inward convection that causes the massive energy loss. In addition, the micro-scale turbulence, including magnetic fluctuations and density fluctuations, increases before the small collapse, and more significantly towards the TQ. Also, temperature fluctuations measured by electron cyclotron emission imaging enhances dramatically at the reconnection site and expand into the island when approaching the small collapse and TQ, and the expansion is more significant close to the TQ. The observed turbulence enhancement near the X-point cannot be fully interpreted by the linear stability analysis by GENE. Evidences suggest that nonlinear effects, such as the reduction of local [Formula: see text] shear and turbulence spreading, may play an important role in governing turbulence enhancement and expansion. These results imply that the turbulence and its interaction with the island facilitate the stochasticity of the magnetic flux and formation of the cold bubble, and hence, the plasma disruption.

9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(1): 58-62, 2023 Jan 06.
Article in Chinese | MEDLINE | ID: mdl-36655259

ABSTRACT

To develop a caregiver parenting behavior scale for children aged 2 to 6 years, and to verify its reliability and validity. This study recruited 1 350 caregivers of children aged 2 to 6 years. The item discrimination analysis and exploratory factor analysis were used to analyze the structure, dimensions and items of the scale. Homogeneity reliability, split-half reliability and test-retest reliability were used to analyze the reliability of the scale. Content validity and construct validity were used to analyze the validity of the scale. The results showed that the final scale contained 7 dimensions and 45 items. Cronbach's α coefficient of the total scale was 0.945; the coefficient of split half was 0.899; the test-retest reliability analysis showed that the correlation coefficients between the two tests were 0.893 (total score), 0.854 (social), 0.832 (language), 0.871 (gross motor), 0.893 (fine motor), 0.862 (cognitive), 0.832 (self-care), and 0.872 (sensory). The content validity analysis was carried out by two rounds of expert argumentation using Delphi expert consultation method. The Kendall coefficient of the items score in two rounds of Delphi expert consultation was 0.813 (P<0.01). The structure validity analysis showed that there were significant correlations between each dimension and the total scale, also between each dimension of the scale, and the extracted average variance values of each dimension was greater than the correlation coefficients between this dimension and other dimensions. In conclusion, the reliability and validity of the scale are qualified. It can be used as a tool to evaluate and guide the parenting behavior of caregivers of children aged 2 to 6 years.


Subject(s)
Caregivers , Parenting , Humans , Child , Caregivers/psychology , Reproducibility of Results , Surveys and Questionnaires , Factor Analysis, Statistical , Psychometrics/methods
10.
Zhonghua Xue Ye Xue Za Zhi ; 44(12): 1022-1026, 2023 Dec 14.
Article in Chinese | MEDLINE | ID: mdl-38503526

ABSTRACT

Objective: This study aimed to evaluate the effect of early tocilizumab intervention to relieve cytokine release syndrome (CRS) following chimeric antigen receptor T cell (CAR-T) therapy. Methods: Twenty-two patients with acute lymphoblastic leukemia who received tocilizumab to relieve CRS response after CAR-T cell infusion in our research center from October 2015 to July 2021 were retrospectively analyzed. According to the timing of tocilizumab intervention, patients were divided into the conventional and early intervention groups. Patients who received tocilizumab treatment after sustained high fever for 4 h were included in the early intervention group. The clinical data, CRS grade, and event-free survival (EFS) between the two groups were evaluated. Results: Compared with patients who used tocilizumab after severe CRS, no patients in the early intervention group died from CRS, and there was no increased risk of neurotoxicity. Eleven patients (84.62%) achieved complete remission with minimal residual lesions. The median EFS of patients in the early intervention and conventional groups was 2 (95% CI 0-5) and 7 (95% CI 3-11) months, respectively. Conclusion: Early tocilizumab intervention in patients with CRS reduces severe CRS and provides a more optimized therapeutic strategy for CRS caused by CAR-T cell therapy.


Subject(s)
Antibodies, Monoclonal, Humanized , Cytokine Release Syndrome , Receptors, Chimeric Antigen , Humans , Cytokine Release Syndrome/etiology , Cytokine Release Syndrome/therapy , Receptors, Chimeric Antigen/therapeutic use , Receptors, Antigen, T-Cell , Retrospective Studies , Immunotherapy, Adoptive/adverse effects , Fever/complications , Fever/drug therapy , Cell- and Tissue-Based Therapy/adverse effects
11.
Acta Gastroenterol Belg ; 85(4): 593-600, 2022.
Article in English | MEDLINE | ID: mdl-36566369

ABSTRACT

Background and study aims: Glucocorticoid (GC) treatment for liver failure is controversial. This study sought to evaluate the efficacy and predictive factors of glucocorticoid therapy for hepatitis B virus-related acute-on-chronic liver failure (HBV- ACLF). Patients and methods: A total of 302 patients with HBV- ACLF were enrolled and categorized by treatment modality (GC vs. Control). Baseline characteristics, liver function, disease complications, and mortality were recorded. Univariate and multivariate analysis were used to identify predictive factors for HBV-ACLF-related mortality. Results: GC therapy significantly improved the 30- and 60-day mortality of HBV-ACLF patients (4.64% vs. 11.92%, P=0.022 and 16.56% vs. 25.83%, P=0.049 for the Control and GC groups, respectively) and GC was an independent prognostic factor for 30-day mortality (OR = 0.177, 95% CI 0.051-0.616, P = 0.007). However, enhanced survival was not associated with improved liver function. There were no significant differences in the incidence of complications (i.e., ascites, bacterial infection, encephalopathy, hepatorenal syndrome, and gastrointestinal bleeding) between the GC and Control groups (P >0.05), except that fungal infection occurred with higher frequency in the GC group (P = 0.037). A significant improvement in the 30-day survival associated with GC therapy was observed among patients <40 years of age, a Model for End-stage Liver Disease (MELD) score of 25-35 or a CLIF- Consortium ACLF (CLIF-C ACLF) grade 0-1 (all P <0.05). Conclusions: GC therapy improved the short-term (30- and 60- day) mortality of patients with HBV-ACLF. This treatment may be of particular benefit to patients who are <40 years of age, have a MELD score of 25-35, or have a CLIF-C ACLF grade of 0-1. (Acta gastroenterol. belg., 2022, 85, 593-600).


Subject(s)
Acute-On-Chronic Liver Failure , End Stage Liver Disease , Hepatitis B , Humans , Hepatitis B virus , Glucocorticoids/therapeutic use , Acute-On-Chronic Liver Failure/drug therapy , Acute-On-Chronic Liver Failure/complications , End Stage Liver Disease/drug therapy , End Stage Liver Disease/complications , Prognosis , Retrospective Studies , Severity of Illness Index , Hepatitis B/complications
12.
Front Bioeng Biotechnol ; 10: 1042128, 2022.
Article in English | MEDLINE | ID: mdl-36507256

ABSTRACT

Chronic osteomyelitis is one of the most challenging diseases in orthopedic treatment. It is usually treated with intravenous antibiotics and debridement in clinical practice, which also brings systemic drug side effects and bone defects. The local drug delivery system of antibiotics has the characteristics of targeted slow release to the lesion site, replacing systemic antibiotics and reducing the toxic and side effects of drugs. It can also increase the local drug concentration, achieve sound bacteriostatic effects, and promote bone healing and formation. Currently, PMMA beads are used in treating chronic osteomyelitis at home and abroad, but the chain beads need to be removed after a second operation, inconveniences patients. Biodegradable materials have been extensively studied as optimal options for antibiotic encapsulation and delivery, bringing new hope for treating chronic osteomyelitis. This article reviews the research progress of local drug delivery systems based on biodegradable polymers, including natural and synthetic ones, in treating chronic osteomyelitis.

13.
Phys Rev Lett ; 129(15): 156401, 2022 Oct 07.
Article in English | MEDLINE | ID: mdl-36269973

ABSTRACT

Chiral materials have attracted significant research interests as they exhibit intriguing physical properties, such as chiral optical response, spin-momentum locking, and chiral induced spin selectivity. Recently, layered transition metal dichalcogenide 1T-TaS_{2} has been found to host a chiral charge density wave (CDW) order. Nevertheless, the physical consequences of the chiral order, for example, in electronic structures and the optical properties, are yet to be explored. Here, we report the spectroscopic visualization of an emergent chiral electronic band structure in the CDW phase, characterized by windmill-shaped Fermi surfaces. We uncover a remarkable chirality-dependent circularly polarized Raman response due to the salient in-plane chiral symmetry of CDW, although the ordinary circular dichroism vanishes. Chiral Fermi surfaces and anomalous Raman responses coincide with the CDW transition, proving their lattice origin. Our Letter paves a path to manipulate the chiral electronic and optical properties in two-dimensional materials and explore applications in polarization optics and spintronics.

14.
Front Bioeng Biotechnol ; 10: 864041, 2022.
Article in English | MEDLINE | ID: mdl-35464725

ABSTRACT

In this study, poly (trimethylene carbonate) (PTMC) with excellent biocompatibility was synthesized via ring-opening of TMC to prepare the Ciprofloxacin-loaded PTMC implants, and antibacterial effects in vitro or in vivo of the resulting implants were investigated to evaluate the potential for treating chronic osteomyelitis. The in vitro results showed the Ciprofloxacin-loaded PTMC implants could sustain release ciprofloxacin at a release amount of about 90 µg/d for 28 days and possessed excellent antibacterial effect, as evidenced by the smaller size of the antibacterial ring of 32.6 ± 0.64 mm and the biofilm inhibition of 60% after 28 days of release. The in vivo results showed that after 28 days of treatment, the body weight and the white blood cell counts of chronic-osteomyelitis-model rats in the treatment group reached 381.6 ± 16.8 g and (7.86 ± 0.91) ×109/L, respectively, returning to normal rapidly compared with the control and blank group, indicating the remarkable antibacterial effect of the Ciprofloxacin-loaded PTMC implants. X-ray images and HE staining results also confirmed that most of the proximal and middle parts of the tibia returned to typical structures and new and trabecular bone had been formed for the rats in the treatment group, and no inflammatory cells were found as compared to the control and blank groups, after 28 days of treatment. The significant lower number of colonies of (9.92 ± 1.56) × 10 CFU/g in the treatment group also suggests that the Ciprofloxacin-loaded PTMC implants achieve a practical antibacterial effect through a local application.

15.
J Phys Condens Matter ; 34(17)2022 Feb 28.
Article in English | MEDLINE | ID: mdl-35120342

ABSTRACT

We have carried out a high-pressure study on monoclinic fergusonite-type YbNbO4. Synchrotron powder x-ray diffraction experiments and density-functional theory simulations have been performed. We found a gradual increase of symmetry under compression, with calculations predicting a second-order monoclinic-tetragonal transition at 15 GPa. However, experiments provided evidence of a transition at 11.6 GPa to a triclinic structure, described by space groupP1¯. The appearance of the triclinic phase, which according to calculations is dynamically unstable under hydrostatic conditions, seems to be related to the presence of non-hydrostatic stresses. The triclinic high-pressure phase remains stable up to 31.9 GPa and the phase transition is not reversible. We have determined the pressure dependence of unit-cell parameters of both phases and calculated their room-temperature equation of state. For the fergusonite-phase we have also obtained the isothermal compressibility tensor. In addition to the high-pressure studies, we report ambient-pressure Raman and infrared spectroscopy measurements which have been compared with density-functional theory calculations.

16.
Biomed Res Int ; 2022: 6916179, 2022.
Article in English | MEDLINE | ID: mdl-35097125

ABSTRACT

OBJECTIVE: To observe the dynamic changes in oxidative stress and the expression levels of antioxidant and oxidative parameters in the blood and synovial fluid in the osteochondral defects of the rabbit knee joints and to explore the significance. METHODS: Thirty New Zealand white rabbits were randomly selected and divided into a blank control group (n = 10), a model control group (n = 10), and an osteochondral defect group (n = 10). The osteochondral defect model of rabbit knee joint was constructed by medial parapatellar arthrotomy. The expression levels of glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), and 8-hydroxydeoxyguanosine (8-OHdG) in peripheral venous blood and knee synovial fluid of the three groups were measured at the end of the 4th, 8th, and 12th weeks after treatment. RESULTS: The expression levels of GSH and SOD in the blood and synovial fluid in the osteochondral defect group at the end of the 8th and 12th weeks were observably lower than those of the other two groups (P < 0.05); higher expression levels of MDA and 8-OHdG in the blood and synovial fluid of the osteochondral defect group compared with those of the other two groups were obtained (P < 0.05). At the end of the 4th, 8th, and 12th weeks, the expression levels of MDA and 8-OHdG in the blood and synovial fluid of the osteochondral defect group presented an upward trend (P < 0.05). CONCLUSION: The osteochondral defects initiate the oxidative stress in the body, which is presented as the decrease of GSH and SOD expression, and the upregulation of MDA and 8-OHdG expression.


Subject(s)
Knee Joint , Superoxide Dismutase , 8-Hydroxy-2'-Deoxyguanosine , Animals , Glutathione/metabolism , Knee Joint/metabolism , Malondialdehyde/metabolism , Rabbits , Superoxide Dismutase/metabolism
17.
Rev Sci Instrum ; 92(6): 063513, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-34243534

ABSTRACT

Remote control of the diagnostic systems is the basic requirement for the high performance plasma operation in a fusion device. This work presents the development of the remote control system for the multichannel Doppler backward scattering (DBS) reflectometers. It includes a remote controlled quasi-optical system and a remote intermediate frequency (IF) amplifier gain control system. The quasi-optical system contains a rotational polarizer, its polarization angle is tunable through a remote controlled motor, and it could combine the microwave beams with a wide frequency range into one focused beam. The remote IF gain control system utilizes the digital microcontroller (MCU) technique to regulate the signal amplitude for each signal channel. The gain parameters of amplifiers are adjustable, and the feedback of working status in the IF system will be sent to MCU in real time for safe operation. The gain parameters could be controlled either by the Ethernet remote way or directly through the local control interface on the system. Preliminary experimental results show the effectiveness of the remote controlled multichannel DBS system.

18.
Nat Commun ; 12(1): 2874, 2021 May 17.
Article in English | MEDLINE | ID: mdl-34001892

ABSTRACT

Topological superconductors (TSCs) are unconventional superconductors with bulk superconducting gap and in-gap Majorana states on the boundary that may be used as topological qubits for quantum computation. Despite their importance in both fundamental research and applications, natural TSCs are very rare. Here, combining state of the art synchrotron and laser-based angle-resolved photoemission spectroscopy, we investigated a stoichiometric transition metal dichalcogenide (TMD), 2M-WS2 with a superconducting transition temperature of 8.8 K (the highest among all TMDs in the natural form up to date) and observed distinctive topological surface states (TSSs). Furthermore, in the superconducting state, we found that the TSSs acquired a nodeless superconducting gap with similar magnitude as that of the bulk states. These discoveries not only evidence 2M-WS2 as an intrinsic TSC without the need of sensitive composition tuning or sophisticated heterostructures fabrication, but also provide an ideal platform for device applications thanks to its van der Waals layered structure.

19.
J Phys Condens Matter ; 33(13)2021 Jan 25.
Article in English | MEDLINE | ID: mdl-33401256

ABSTRACT

Topological semimetals have attracted significant attentions owing to their potential applications in numerous fields such as low-power electron devices and quantum computation, which are closely related to their thermal transport properties. In this work, the phonon transport properties of topological Dirac nodal-line semimetals ZrGeX(X= S, Se, Te) with the PbClF-type structures are systematically studied using the first-principles calculations combined with the Boltzmann transport theory. The obtained lattice thermal conductivities show an obvious anisotropy, which is caused by the layer structures of ZrGeX(X= S, Se, Te). The room-temperature lattice conductivity of ZrGeTe alongcdirection is found to be as low as 0.24 W m-1 K-1, indicating that it could be of great significance in the fields of thermal coating materials and solar cell absorber. In addition, we extract each phonon branch from group velocities, phonon scattering rates, Grüneisen parameters, and phase space volumes to investigate the mechanism underlying the low thermal conductivity. It is concluded that the difference of thermal conductivities of three materials may be caused by the number of scattering channels and the effect of anharmonic. Furthermore, the phonon mean free path alongadirection is relatively longer. Nanostructures or polycrystalline structures may be effective to reduce the thermal conductivity and improve the thermoelectric properties.

20.
RSC Adv ; 11(5): 3058-3070, 2021 Jan 11.
Article in English | MEDLINE | ID: mdl-35424262

ABSTRACT

The particle swarm optimization algorithm and density functional theory (DFT) are extensively performed to determine the structures, phase transition, mechanical stability, electronic structures, and thermodynamic properties of lanthanide phosphates (LaP and LaAs) in the pressure range of 0 to 100 GPa. Two novel high-pressure structures of LaP and LaAs are first reported here. It is found that LaX (X = P, As) undergo a phase transition from NaCl-type structure (Fm3m) to CsCl-type structure (P4/mmm) at 19.04 GPa and 17.22 GPa, respectively. With the elevation of the pressure, C2/m-LaP and Imma-LaAs are the most stable structures up to 70.08 GPa and 85.53 GPa, respectively. Finally, the analysis of the elastic constants and hardness confirms that the C2/m-LaP possesses hardness values up to 23.24 GPa due to the strong covalent P-P bonding and ionic La-P bonding, indicating that it is a potential hard material.

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