Dehydrogenation of formic acid over Pd/C catalysts: Insight into the cold plasma treatment

Safe and efficient generation of renewable hydrogen via dehydrogenation of cheap and sustainable formic acid using supported Pd catalysts has attracted significant interest. Non-thermal (cold) plasma is demonstrably a fast...</p

Transcranial ultrasonic wave propagation simulation: skull insertion loss and recovery

Severe energy dissipation and waveform aberration in ultrasonic wave propagation due to the human skull remain major challenges to achieving good focus in high intensity focused ultrasound (HIFU) brain therapy and high-resolution thermoacoustic tomography (TAT) of the human brain. With the inclusion of the skull insertion loss, we numerically simulated the ultrasonic wave propagation using the pseudospectral time domain (PSTD) algorithm for TAT setup. We then applied the redatuming scheme through downward and upward continuation originated in seismic signal processing to eliminate the diffraction caused by the irregularity of the skull and to recover the insertion loss due mainly to the diploes layer of the skull. This approach, after further validation, is aimed to recover wave energy dissipation and waveform aberration in ultrasonic measurements applied to both trans-skull imaging (ultrasound propagates outward) and therapy (ultrasound propagates inward)

Functional and effective connectivity analysis of drug-resistant epilepsy: a resting-state fMRI analysis

ObjectiveEpilepsy is considered as a neural network disorder. Seizure activity in epilepsy may disturb brain networks and damage brain functions. We propose using resting-state functional magnetic resonance imaging (rs-fMRI) data to characterize connectivity patterns in drug-resistant epilepsy.MethodsThis study enrolled 47 participants, including 28 with drug-resistant epilepsy and 19 healthy controls. Functional and effective connectivity was employed to assess drug-resistant epilepsy patients within resting state networks. The resting state functional connectivity (FC) analysis was performed to assess connectivity between each patient and healthy controls within the default mode network (DMN) and the dorsal attention network (DAN). In addition, dynamic causal modeling was used to compute effective connectivity (EC). Finally, a statistical analysis was performed to evaluate our findings.ResultsThe FC analysis revealed significant connectivity changes in patients giving 64.3% (18/28) and 78.6% (22/28) for DMN and DAN, respectively. Statistical analysis of FC was significant between the medial prefrontal cortex, posterior cingulate cortex, and bilateral inferior parietal cortex for DMN. For DAN, it was significant between the left and the right intraparietal sulcus and the frontal eye field. For the DMN, the patient group showed significant EC connectivity in the right inferior parietal cortex and the medial prefrontal cortex for the DMN. There was also bilateral connectivity between the medial prefrontal cortex and the posterior cingulate cortex, as well as between the left and right inferior parietal cortex. For DAN, patients showed significant connectivity in the right frontal eye field and the right intraparietal sulcus. Bilateral connectivity was also found between the left frontal eye field and the left intraparietal sulcus, as well as between the right frontal eye field and the right intraparietal sulcus. The statistical analysis of the EC revealed a significant result in the medial prefrontal cortex and the right intraparietal cortex for the DMN. The DAN was found significant in the left frontal eye field, as well as the left and right intraparietal sulcus.ConclusionOur results provide preliminary evidence to support that the combination of functional and effective connectivity analysis of rs-fMRI can aid in diagnosing epilepsy in the DMN and DAN networks

Endometrial Cytology as a Method to Improve the Accuracy of Diagnosis of Endometrial Cancer: Case Report and Meta-Analysis

More and more researchers have reported that dilatation and curettage (D&amp;C) or Pipelle had low accuracy, high misdiagnosis, and insufficient rate. Endometrial cytology is often compared with histology and seems to be an efficient method for the diagnosis of endometrial disorders, especially endometrial cancer. We report a case of misdiagnosed endometrial cancer by D&amp;C, but with a positive cytopathological finding. Following that, a meta-analysis including 4,179 patients of endometrial diseases with cyto-histopathological results was performed to assess the value of the endometrial cytological method in endometrial cancer diagnosis. The pooled sensitivity and specificity of the cytological method in detecting endometrial atypical hyperplasia or cancer was 0.91[95% confidence interval (CI) 0.74–0.97] and 0.96 (95% CI 0.90–0.99), respectively. The pooled positive likelihood ratio and negative likelihood ratio was 25.4 (95% CI 8.1–80.1) and 0.10 (95% CI 0.00–0.30), respectively. The diagnostic odds ratio which was usually used to evaluate the diagnostic test performance reached 260 (95% CI 36–1905). So we recommend that D&amp;C and Pipelle are still practical procedures to evaluate the endometrium, cytological examinations should be utilized as an additional endometrial assessment method

An Efficacious Endometrial Sampler for Screening Endometrial Cancer

Recently, the research on early detection of precancerous change and endometrial carcinoma has been focusing on minimally invasive procedures for screening. On this basis, we aim to verify the feasibility of endometrial samplers for screening endometrial cancer using Li Brush. We recruited patients undergoing hysterectomy for different diseases from the Inpatient Department of the Department of Obstetrics and Gynecology. Before surgery, endometrial cells were collected by Li Brush. The cytopathologic diagnosis from Li Brush and the histopathologic diagnosis from hysterectomy in the same patient were compared to calculate sensitivity (Se), specificity (Sp), false-negative rate (FNR), false-positive rate (FPR), positive predictive value (PV+) %, and negative predictive value (PV-). The research enrolled 293 women into this self-controlled trial. According to the hypothesis test of paired four lattices, we obtained the following indicators: Se 92.73, Sp 98.15, FNR 7.27, FPR 1.85, PV+92.73, and PV−98.15%. The endometrial sampler Li Brush is an efficacious instrument for screening endometrial cancer

Cooling and Water Production in a Hybrid Desiccant M-Cycle Evaporative Cooling System with HDH Desalination: A Comparison of Operational Modes

In this paper, the cooling and freshwater generation performance of a novel hybrid configuration of a solid desiccant-based M-cycle cooling system (SDM) combined with a humidification–dehumidification (HDH) desalination unit is analysed and compared in three operational modes: ventilation, recirculation, and half recirculation. The HDH unit in this system recycles the moist waste air sourced from the M-cycle cooler and rotary desiccant wheel of the SDM system to enhance water production. A mathematical model was established and solved using TRNSYS and EES software. The results of this study indicate that the recirculation mode exhibited superior cooling performance compared to the other two modes, producing up to 7.91 kW of cooling load and maintaining a supply air temperature below 20.85 °C and humidity of 12.72 g/kg under various ambient conditions. All the operational modes showed similar water production rates of around 52.74 kg/h, 52.43 kg/h, and 52.14 kg/h for the recirculation, half-recirculation and ventilation modes, respectively, across a range of operating temperatures. The recirculation mode also exhibited a higher COP compared to the other modes, as the environmental temperature and relative humidity were above 35 °C and 50%. However, it should be noted that the implementation of the recirculation mode resulted in a higher water consumption rate, with a maximum value of 5.52 kg/h when the inlet air reached 45 °C, which partially offset the benefits of this mode

Positive rate of malignant cells in endometrial cytology samples of ovarian cancer, fallopian tube cancer, and primary peritoneal cancer patients: A systematic review and meta-analysis

To estimate the feasibility of diagnosing ovarian cancer, fallopian tube cancer, and primary peritoneal cancer through endometrial cytology, we performed a systematic review and meta-analysis to calculate the pooled positive rate of malignant cells in endometrial cytology samples. We queried PubMed, EMBASE, Medline, and Cochrane Central Register of Controlled Trails from inception to November 12, 2020 for studies estimating positive rates of malignant cells in endometrial cytology samples from patients with ovarian cancer, fallopian tube cancer, and primary peritoneal cancer. The positive rates of the included studies were calculated as pooled positive rate through meta-analyses of proportion. Subgroup analysis based on different sampling methods was conducted. Seven retrospective studies involving 975 patients were included. Pooled positive rate of malignant cells in endometrial cytology specimens of ovarian cancer, fallopian tube cancer, and primary peritoneal cancer patients was 23% (95% CI: 16% - 34%). Statistical heterogeneity between the included studies was considerable (I2 = 89%, P < 0.01). The pooled positive rates of the group of brushes and the group of aspiration smears were 13% (95% CI: 10% - 17%, I2 = 0, P = 0.45) and 33% (95% CI: 25% - 42%, I2 = 80%, P < 0.01), respectively. Although endometrial cytology is not an ideal diagnostic tool for ovarian cancer, fallopian tube cancer, and primary peritoneal cancer, it is a convenient, painless, and easy-to-implement adjunct to other tools. Sampling method is one of the factors that affect the detection rate

Experimental Study on Electric Potential Response Characteristics of Gas-Bearing Coal During Deformation and Fracturing Process

Coal mass is deformed and fractured under stress to generate electrical potential (EP) signals. The mechanical properties of coal change with the adsorption of gas. To investigate the EP response characteristics of gas-bearing coal during deformation and fracture, a test system to monitor multi-parameters of gas-bearing coal under load was designed. The results showed that abundant EP signals were generated during the loading process and the EP response corresponded well with the stress change and crack expansion, and validated this with the results from acoustic emission (AE) and high-speed photography. The higher stress level and the greater the sudden stress change led to the greater EP abnormal response. With the increase of gas pressure, the confining action and erosion effect are promoted, causing the damage evolution impacted and failure characteristics changes. As a result, the EP response is similar while the characteristics were promoted. The EP response was generated due to the charge separation caused by the friction effect etc. during the damage and deformation of the coal. Furthermore, the main factors of the EP response were different under diverse loading stages. The presence of gas promoted the EP effect. When the failure of the coal occurred, EP value rapidly rose to a maximum, which could be considered as an anomalous characteristic for monitoring the stability and revealing failure of gas-bearing coal. The research results are beneficial for further investigating the damage-evolution process of gas-bearing coal

“Storage-Discharge” Ethanol Cold Plasma for Synthesizing High Performance Pd/Al2O3 Catalysts

Atmospheric pressure cold plasma is an environmentally friendly and novel method to synthesize supported metal catalysts, which usually uses active hydrogen species to reduce metal ions. Ethanol is a hydrogen-rich renewable liquid hydrogen source, and it is more convenient to store and transport than H2. In this study, a &ldquo;storage-discharge&rdquo; ethanol cold plasma was used to prepare Pd/Al2O3-EP catalysts, and the obtained catalysts are used for CO oxidation. The complete oxidation of CO temperature (T100) over Pd/Al2O3-EP was 145 &deg;C, which was comparable to the performance of Pd/Al2O3-HP that was synthesized by atmospheric pressure hydrogen cold plasma. Pd/Al2O3-EP-C obtained by calcining Pd/Al2O3-EP at 450 &deg;C for 2 h in air atmosphere in order to remove residual carbon species showed much higher CO oxidation activity, and T100 was 130 &deg;C. The Pd/Al2O3 catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron diffraction (XPS), Brunauer&ndash;Emmett&ndash;Teller (BET), and transmission electron microscopy (TEM), and the structure-performance relationship was analyzed. The results indicate that the &ldquo;storage-discharge&rdquo; ethanol cold plasma can reduce the Pd precursor ions into metallic Pd state, and the dissociation of ethanol forms lots of highly active chemisorbed oxygen species, which can enhance the performance of Pd/Al2O3-EP for CO oxidation. In contrast, Pd/Al2O3-EP-C shows much higher CO oxidation activity, which is mainly attributed to the removal of the residual carbon species, and the exposure of more Pd active sites and chemisorbed oxygen species. The &ldquo;storage-discharge&rdquo; ethanol cold plasma is a safe and efficient novel method for synthesizing supported Pd catalysts, and it has important potential for the preparation and application of supported metal catalysts