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1.
J Am Chem Soc ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38968087

RESUMEN

Molecule-inclusive closed cage compounds present a unique platform for molecular motion in an isolated environment. This study showcases the incorporation of a tadpole-like polar molecule (1-propyl-1H-imidazole, PIm) into a supramolecular cage formed by duad semicage p-tert-butylcalix[4]arene. The ferroelectric phase transition as well as the cage-confined motion of encapsulated PIm was studied in detail. The unusual quadrastable state of the PIm in the paraelectric phase allows for the modulation of dipolar polarization over a broad temperature/frequency range. This compound represents the first example of a clathrate molecular ferroelectric featuring a molecule-inclusive supramolecular cage, and it also contributes to the understanding of cage-confined molecular dynamics.

2.
Inorg Chem ; 63(17): 7966-7972, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38620044

RESUMEN

Hybrid ferroelastic crystals have emerged as a hot research topic in recent years owing to their prospective applications in piezoelectric sensors, mechanical switches, and optoelectronic devices. Nevertheless, most of the documented materials exhibit one-step or two-step ferroelastic phase transition(s), and those with multistep ferroelastic transitions are extremely scarce. We present a new hexagonal molecular perovskite based on a fluoro-substituted flexible cyclic ammonium cation, (1-fluoromethyl-1-methylpyrrolidine)[CdCl3] (1), undergoing unusual three-step ferroelastic phase transitions from hexagonal paraelastic phase to orthorhombic, monoclinic, and triclinic ferroelastic phases at 388, 376, and 311 K, respectively, with Aizu notation of 6/mmmFmmm, mmmF2/m, and 2/mF-1, featuring spontaneous strain of 0.002, 0.023, and 0.110, respectively. Furthermore, variable-temperature single-crystal diffraction reveals that the phase-transition mechanism in 1 principally originates from intriguing dynamic change of organic cations and synchronous displacement of inorganic chains. This scarce instance of multistep hybrid ferroelastic provides important clues for finding advanced ferroelastic materials.

3.
Artif Organs ; 48(1): 37-49, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37846614

RESUMEN

BACKGROUND: The artificial anal sphincter (AAS) system has gained significant attention as a solution for treating fecal incontinence (FI). It relies on transcutaneous energy transfer (TET) as its primary energy source. However, changes in posture or biological tissue can cause misalignment of the coil, resulting in unstable power reception. Inadequate power affects charging efficiency, while excessive power leads to excessive heating at the receiver side. Consequently, achieving safe and constant voltage charging for the AAS becomes a complex challenge. METHODS: To maintain a consistent charging voltage and overcome the issue of variations in load and coil coupling strength, this article proposes a wireless charging control system that utilizes an LCC-S-type resonant network and phase shift to adjust the transmitting voltage based on feedback charging voltage in real time. In particular, the PI controller and neural network are introduced to change the phase-shift angle swiftly. The dynamic performance is then evaluated under different misalignments and presented with comparative results. RESULTS: The results indicate that the multilayer perceptron control system outperforms the PI. Under the complex misalignment disturbance, the average error of receiver side load voltage is only 0.007 V, with an average settling time of 960 ms. Additionally, the average temperature at the receiver side is 40.4°C. CONCLUSION: The experiments demonstrate that the proposed system effectively addresses the misalignment issue in TET during the charging, ensuring constant voltage charging at the receiver side and thermal safety.


Asunto(s)
Órganos Artificiales , Esfínter Urinario Artificial , Canal Anal/cirugía , Transferencia de Energía , Redes Neurales de la Computación
4.
J Integr Neurosci ; 23(6): 116, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38940089

RESUMEN

BACKGROUND: The effects of heat acclimation (HA) on the hypothalamus after exertional heatstroke (EHS) and the specific mechanism have not been fully elucidated, and this study aimed to address these questions. METHODS: In the present study, rats were randomly assigned to the control, EHS, HA, or HA + EHS groups (n = 9). Hematoxylin and eosin (H&E) staining was used to examine pathology. Tandem mass tag (TMT)-based proteomic analysis was utilized to explore the impact of HA on the protein expression profile of the hypothalamus after EHS. Bioinformatics analysis was used to predict the functions of the differentially expressed proteins. The differential proteins were validated by western blotting. An enzyme-linked immunosorbent assay was used to measure the expression levels of inflammatory cytokines in the serum. RESULTS: The H&E staining (n = 5) results revealed that there were less structural changes in hypothalamus in the HA + EHS group compared with the EHS group. Proteomic analysis (n = 4) revealed that proinflammatory proteins such as argininosuccinate synthetase (ASS1), high mobility group protein B2 (HMGB2) and vimentin were evidently downregulated in the HA + EHS group. The levels of interleukin (IL)-1ß, IL-1, and IL-8 were decreased in the serum samples (n = 3) from HA + EHS rats. CONCLUSIONS: HA may alleviate hypothalamic damage caused by heat attack by inhibiting inflammatory activities, and ASS1, HMGB2 and vimentin could be candidate factors involved in the exact mechanism.


Asunto(s)
Golpe de Calor , Hipotálamo , Proteómica , Ratas Sprague-Dawley , Animales , Hipotálamo/metabolismo , Golpe de Calor/metabolismo , Ratas , Masculino , Esfuerzo Físico/fisiología , Modelos Animales de Enfermedad
5.
J Perianesth Nurs ; 39(1): 66-72, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37768264

RESUMEN

PURPOSE: This aim of this study was to compare two anesthetic regimens in terms of extubation time and postoperative recovery in children undergoing ambulatory adenoidectomy. DESIGN: A retrospective cohort study with propensity score matching. METHODS: The medical charts of 452 children aged between 3 and 8 years undergoing ambulatory adenoidectomy were retrieved for analysis, of which 438 were eligible to participate in this study. A majority (n = 327) were children exposed to a conventional propofol-pronounced general anesthetic regimen (high-dose propofol plus low-dose remifentanil, labeled as group P), while n = 111 were administered a modified remifentanil-pronounced anesthetic regimen (low-dose propofol plus high-dose remifentanil, namely group R). Propensity score matching was employed to adjust for confounders, resulting in 69 matched patients in each group. The primary endpoint of this study was extubation time. The secondary endpoints were total intraoperative fluid volume, length of stay in the postanesthesia care unit (PACU), postoperative pain rating, the incidence of emergence agitation, nausea and vomiting, as well as the level of consciousness (fully awake or waking by gentle patting) when transferred out of PACU, and any major complications (wound bleeding, reintubation, readmission, and overnight stay). FINDINGS: No major complications were observed in both groups. Compared to group P, group R had significantly shorter extubation time (8.2 ± 1.4 minutes vs 13.3 ± 2.4 minutes, P < .001), shorter length of stay in the PACU (14.1 ± 3.1 minutes vs 20.2 ± 3.4 minutes, P < .001), and a higher proportion of cases being fully awake when transferred out of the PACU (91% vs 46%, P < .001). Lastly, the pain rating, frequency of oropharyngeal airway usage, incidence of emergence agitation, and nausea and vomiting were comparable between the two groups (P > .05 for all). CONCLUSIONS: Remifentanil-pronounced anesthesia was superior to propofol-pronounced anesthesia in children undergoing ambulatory adenoidectomy, given that the former was associated with a faster recovery time from anesthesia without jeopardizing patient safety.


Asunto(s)
Delirio del Despertar , Propofol , Niño , Humanos , Preescolar , Remifentanilo , Anestésicos Intravenosos , Estudios Retrospectivos , Adenoidectomía , Extubación Traqueal , Anestesia General , Vómitos , Náusea , Periodo de Recuperación de la Anestesia
6.
Opt Express ; 31(4): 7023-7031, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36823947

RESUMEN

Due to the fascinating features, pulsating solitons attract much attention in the field of nonlinear soliton dynamics and ultrafast lasers. So far, most of the investigations on pulsating soliton are conducted in Er-doped fiber lasers. In this work, we reported the periodic transition between two evolving pulsating soliton states in an Yb-doped fiber laser. By using the real-time measurement techniques, the spectral and temporal characteristics of this transition state were investigated. Two evolving soliton pulsation states have similar evolution process, i.e., from pulsating towards quasi-stable mode-locked states. However, the details of the two processes are different, such as the pulse energy levels, pulsating modulation depths, duration of quasi-stable mode-locked states. The transition between two evolving soliton pulsation states could be attributed to the interaction of the polarizer and the varying polarization states of the pulse inside the laser cavity. The experimental results will contribute to the further understanding of soliton pulsating dynamics in dissipative optical systems.

7.
Artif Organs ; 46(5): 794-803, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34845737

RESUMEN

BACKGROUND: Artificial anal sphincter (AAS), as an advanced device, has been widely investigated by researchers around world. But the reliability of the structure is still unsatisfactory according to clinical results. What's more, the previous AAS systems are lack the ability of rectal perception as native anal sphincter, which fails to guarantee the safety of the blood supply. In addition, without it, the patient cannot determine when to defecate. METHODS: In order to improve the reliability and safety of current AAS systems, a novel structure AAS system with rectal perception function, based on pressure sensor module, is proposed in this article. The novel AAS system has a closed three-arm clamping mechanism, with transmission structure of cam-follower system. Then, the design, strength check, optimization and force analysis of the proposed mechanism are investigated. After that, to remodel rectal perception function, the novel sensor module system based on strain gauge is established. Finally, in vitro experiments are conducted. RESULTS: In vitro test, the sensor system could monitor the rectal pressure accurately. And when H = 24.6 cm (feeling the urge to have a bowel movement), the clamping pressure is 7.39 kPa. which is also less than the safe pressure 9.33 kPa. CONCLUSIONS: Good performance of the reliability and safety of both novel rectal perception function and new clamping mechanism have been showed.


Asunto(s)
Órganos Artificiales , Incontinencia Fecal , Canal Anal/cirugía , Incontinencia Fecal/cirugía , Humanos , Percepción , Reproducibilidad de los Resultados
8.
Artif Organs ; 46(12): 2391-2399, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35866428

RESUMEN

BACKGROUND: Artificial organs are playing an increasingly important role in medical field. Artificial anal sphincter, as an example, is a widely used medical device for fecal incontinence. Though it could help patients maintain continence, the issue of perception reconstruction is still unsolved, which means that patients cannot control defecation as desired. METHODS: In this paper, a novel sensor system based on vector similarity has been analyzed and evaluated. The sensor system is a self-packaged strain gauge sensor with a small size 14.5 mm × 6 mm, especially for medical device implanted in body to reconstruct perception function. In order to overcome the disadvantages of single threshold judgment, a more accurate and reliable judgment standard for content pressure detection in rectum is developed by using vector similarity method. Therefore, in the novel sensor system, standard multi-parameters are comprehensive considered. Furthermore, weight-optimization of sensors are investigated since each sensor has played a different role in detection. Finally, sensor calibration, in vitro and in vivo experiments are established. RESULTS: In sensor calibration, the result R2 > 0.99 presents the strain gauge pressure sensor has a good linearity. After that, a series of in vitro experiments have been conducted. The optimized sensor system shows a high accuracy rate in perception reconstruction, which is 87.5% on early warning and 95% on the alarm. In the following in vivo experiments. The results indicate that the average accuracy of the proposed perception reconstruction module has increased by 17.7%, compared with that without optimized sensor system. CONCLUSIONS: All of these have proven that the novel perception reconstruction module with sensor system based on vector similarity is more acceptable and reliable.


Asunto(s)
Órganos Artificiales , Incontinencia Fecal , Humanos , Canal Anal/cirugía , Incontinencia Fecal/cirugía , Recto/cirugía , Percepción
9.
Lung ; 200(3): 381-392, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35511293

RESUMEN

INTRODUCTION: Recent studies have reported that ferroptosis is an iron-dependent cell death process and is a potential therapeutic target in various tumours. The purpose of this study was to establish a new algorithm based on the ferroptosis score to ascertain the prognosis and response to immunotherapy of patients with lung squamous cell carcinoma (LUSC). METHODS: The RNA-seq data of patients with LUSC were obtained from The Cancer Genome Atlas and Gene Expression Omnibus databases and merged after removing the inter batch differences. Based on the expression of the ferroptosis-related genes, unsupervised consistent cluster analysis was performed to obtain various ferroptosis-related subgroups. These subgroups were analysed to obtain differentially expressed genes (DEGs). Subsequently, multiple gene clusters were obtained by unsupervised consistent cluster analysis based on the expression of the DEGs. The Boruta algorithm was used to calculate the ferroptosis score. RESULTS: There were significant differences in prognosis amongst the various ferroptosis-related and gene clusters. In addition, the gene set variation analysis revealed that the different ferroptosis-related clusters and gene clusters demonstrated differences in biological pathways. The ferroptosis scores positively correlated with the tumour mutation burden, and patients with lower scores had a better prognosis. In addition, the ferroptosis score was accurate in predicting the effectiveness of immunotherapy. CONCLUSION: There were significant differences in the prognosis and immunotherapy response of patients with LUSC with different ferroptosis scores. Therefore, a comprehensive clinical evaluation of the ferroptosis score of each patient with LUSC is clinically significant.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Carcinoma de Células Escamosas , Ferroptosis , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Ferroptosis/genética , Regulación Neoplásica de la Expresión Génica , Genómica , Humanos , Inmunoterapia , Pulmón/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Pronóstico
10.
Sensors (Basel) ; 22(19)2022 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-36236504

RESUMEN

Monitoring bodily pressure could provide valuable medical information for both doctors and patients. Long-term implantation of in vivo sensors is highly desirable in situations where perception reconstruction is needed. In particular, for fecal incontinence, artificial anal sphincters without perceptions could not remind patients when to defecate and even cause ischemic tissue necrosis due to uncontrolled clamping pressure. To address these issues, a novel self-packaging strain gauge sensor system is designed for in vivo perception reconstruction. In addition, long short-term memory (LSTM) networks, which show excellent performance in processing time series-related features and fitting properties, are used in this article to improve the prediction accuracy of the perception model. The proposed system has been tested and compared with the traditional linear regression (LR) approach using data from in vitro experiments. The results show that the Root-Mean-Square Error (RMSE) is reduced by more than 69%, which demonstrates that the prediction accuracy of the proposed LSTM model is higher than that of the LR model to reach a more accurate prediction of the amount of intestinal content. Furthermore, outcomes of in vivo experiments show that the robustness of the novel sensor system based on long short-term memory networks is verified through experiments with limited data.


Asunto(s)
Incontinencia Fecal , Memoria a Corto Plazo , Canal Anal/cirugía , Incontinencia Fecal/cirugía , Humanos , Memoria a Largo Plazo , Percepción
11.
J Perianesth Nurs ; 37(5): 699-705, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35752525

RESUMEN

PURPOSE: Placement of local anesthetics either as infiltration (LAI) or as abdominal wall nerve block (AWNB) has been shown to reduce postoperative pain following laparoscopic surgery. We aimed to compare intraoperative remifentanil consumption and postoperative pain of AWNB and LAI in children undergoing ambulatory two-port laparoscopic inguinal hernia surgery with propofol-remifentanil based general anesthesia. DESIGN: Randomized controlled trial. METHODS: Children aged between 1 and 6 years undergoing two-port laparoscopic inguinal hernia repair were enrolled for analysis. These children received one of the three anesthesia regimens (1) standard general anesthesia (SGA); (2) SGA with preemptive LAI; (3) SGA with preemptive AWNB; and were categorized accordingly. Primary outcome variable were intraoperative average infusion rate of remifentanil and postoperative FLACC (Face, Legs, Activity, Cry, and Consolability) pain score. Secondary outcome data included demographics, intraoperative variables (hemodynamics and bispectral index score recorded at three different time points), and duration of surgery. FINDINGS: A total of 90 children (30 in each group) were included in the analysis. General information, intraoperative hemodynamic variables, bispectral index score, and duration of surgery were not significantly different among groups. The intragroup variation of hemodynamic variables were less stable in the SGA group compared with the other two groups, while BIS score was similar among groups. The intraoperative infusion rate of remifentanil was significantly lower in the AWNB group than in the SGA or the LAI group (median [25th to 75th centiles]: 0.11[0.11 to 0.11] µg/kg/min, 0.33[0.33 to 0.33] µg/kg/min; 0.17[0.17 to 0.20] µg/kg/min, respectively, P < .001 for both), and lower in the LAI group than in the SGA group (P < .001). The postoperative FLACC pain score was significantly lower in the AWNB group than in the SGA or the LAI group (P < .001 for both). CONCLUSIONS: AWNB is associated with a lower intraoperative remifentanil requirement and a lower postoperative FLACC pain score compared with LAI in children undergoing laparoscopic inguinal hernia repair with propofol-remifentanil based general anesthesia.


Asunto(s)
Pared Abdominal , Hernia Inguinal , Bloqueo Nervioso , Propofol , Analgésicos , Anestésicos Locales , Niño , Preescolar , Hernia Inguinal/cirugía , Humanos , Lactante , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control , Remifentanilo , Ultrasonografía Intervencional
12.
Opt Express ; 29(21): 34684-34694, 2021 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-34809252

RESUMEN

Soliton pulsation is one of the most fascinating phenomena in ultrafast fiber lasers, owing to its rich nonlinear dynamics and potential generation of high peak power pulse. However, it is still a challenge to efficiently search for pulsating soliton in fiber lasers because it requires a fine setting of laser cavity parameters. Here, we report the autosetting soliton pulsation in a passively mode-locked fiber laser. The parameters of electronic polarization controller are intelligently adjusted to search for pulsating soliton state by the improved depth-first search algorithm. Moreover, the intensity modulation depth of pulsating soliton could be flexibly controlled. These findings indicate that the intelligent control of a fiber laser is an effective way to explore on-demand soliton dynamics and is also beneficial to the optimization of ultrafast laser performance.

13.
Chemistry ; 27(63): 15716-15721, 2021 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-34498317

RESUMEN

The multifunctional two-dimensional (2D) organic-inorganic hybrid perovskites have potential applications in many fields, such as, semiconductor, energy storage and fluorescent device etc. Here, a 2D Ruddlesden-Popper (RP) perovskite (IPA)2 (FA)Pb2 I7 (1, IPA+ =C3 H9 NI+ , FA+ =CN2 H5 + ) is determined for its photophysical properties. Strikingly, 1 reveals a solid reversible phase transition with Tc of 382 K accompanied by giant entropy change of 40 J mol-1 K-1 . Further optical investigations indicate that 1 reveals a narrow direct bandgap (2.024 eV) attributed to the slight bending of I-Pb-I edge and inorganic [Pb2 I7 ]n layer and a superior photoluminescence (PL) emission with super long lifetime of 0.1607 ms. It is believed that this work will pave an avenue to further design multifunctional semiconductors that combines energy storage and photoelectric materials.

14.
Chemistry ; 27(54): 13575-13581, 2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34322911

RESUMEN

Molecular ferroelectrics of high-temperature reversible phase transitions are very rare and have attracted increasing attention in recent years. In this paper is described the successful synthesis of a novel high-temperature host-guest inclusion ferroelectric: [(C6 H5 NF3 )(18-crown-6)][BF4 ] (1) that shows a pair of reversible peaks at 348 K (heating) and 331 K (cooling) with a heat hysteresis about 17 K by differential scanning calorimetry measurements, thus indicating that 1 undergoes a reversible structural phase transition. Variable-temperature PXRD and temperature-dependent dielectric measurements further prove the phase-transition behavior of 1. The second harmonic response demonstrates that 1 belongs to a non-centrosymmetric space group at room temperature and is a good nonlinear optical material. In its semiconducting properties, 1 shows a wide optical band gap of about 4.43 eV that comes chiefly from the C, H and O atoms of the crystals. In particular, the ferroelectric measurements of 1 exhibit a typical polarization-electric hysteresis loop with a large spontaneous polarization (Ps ) of about 4.06 µC/cm2 . This finding offers an alternative pathway for designing new ferroelectric-dielectric and nonlinear optical materials and related physical properties in organic-inorganic and other hybrid crystals.

15.
Muscle Nerve ; 64(3): 336-341, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34151436

RESUMEN

INTRODUCTION/AIMS: Exertional rhabdomyolysis (ER) often occurs during prolonged intense exercise in hot environments, posing a threat to the health of military personnel. In this study we aimed to investigate possible risk factors for ER and provide further empirical data for prevention and clinical treatment strategies. METHODS: A retrospective investigation of 116 concurrent ER cases was conducted. Conditional logistic regression analyses were performed to assess the association between each potential risk (or protective) factor and ER. The clinical characteristics of the 71 hospitalized patients were analyzed descriptively. RESULTS: After screening, the following variables significantly increased the risk of ER: shorter length of service (recruits; odds ratios [OR], 7.49; 95% confidence interval [CI], 2.58-21.75); higher body mass index (BMI; OR, 1.14, 95% CI, 1.03-1.26); lack of physical exercise in the last half year (less than once per month; OR, 3.20; 95% CI, 1.08-9.44); and previous heat injury (OR, 2.94; 95% CI, 1.26-6.89). Frequent fruit consumption (OR, 0.57; 95% CI, 0.33-0.99), active hydration habit (OR, 0.37; 95% CI, 0.20-0.67), water replenishment of more than 2 L on the training day (OR, 0.15; 95% CI, 0.05-0.45), and water replenishment of at least 500 mL within 1 hour before training (OR, 0.33; 95% CI, 0.12-0.88) significantly decreased the risk of ER. Of the 71 hospitalized patients, 41 (57.7%) were diagnosed with hypokalemia on admission. DISCUSSION: In military training, emphasis should be placed on incremental adaptation training before more intense training, and close attention should be given to overweight and previously sedentary recruits. Fluid replenishment before exercise, increased fruit intake, and proper potassium supplementation may help prevent ER.


Asunto(s)
Adaptación Fisiológica/fisiología , Índice de Masa Corporal , Ejercicio Físico/fisiología , Esfuerzo Físico/fisiología , Rabdomiólisis/diagnóstico , Adolescente , Humanos , Masculino , Tamizaje Masivo , Personal Militar , Estudios Retrospectivos , Rabdomiólisis/etiología , Rabdomiólisis/fisiopatología , Factores de Riesgo , Factores de Tiempo , Adulto Joven
16.
Inorg Chem ; 60(2): 1195-1201, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33356190

RESUMEN

Due to the existence of some cross properties such as SHG (second-harmonic generation), ferroelectricity, piezoelectricity, and thermoelectricity, molecular ferroelectrics have been widely used as a composite multipurpose material. Particularly, organic-inorganic molecular ferroelectrics have received much interest recently because of their unique flexible structures, friendly environment, ease of synthesis, etc. Also, these hybrids show great flexibility in band-gap engineering. Here we report a new molecular halide, [C6H13N3SbBr5]n (1; C6H13N3 = 1-(3-aminopropyl)imidazole), which experiences a unique ferroelectric to paraelectric phase transition at around 230 K from space group P21 to P21/c. Significantly, compound 1 exhibits a narrow band gap with a value of 2.52 eV, large pronounced SHG-active, perfect rectangle hysteresis loops with a large spontaneous polarization of 6.86 µC/cm2. DSC (differential scanning calorimetry) and dielectric dependence on temperature tests and the volume change before and after the phase transition show that compound 1 is characterized by a second-order phase transition. These findings will contribute to the multifunctional materials field of organic-inorganic hybrids.

17.
Inorg Chem ; 60(24): 18918-18923, 2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34872246

RESUMEN

A novel organic-inorganic hybrid perovskite crystal, [ClC6H4(CH2)2NH3]2CuBr4 (1), having experienced an invertible high-temperature phase transition near Tc (the Curie temperature Tc = 355 K), has been successfully synthesized. The phase-transition characteristics for compound 1 are thoroughly revealed by specific heat capacity (Cp), differential thermal analysis, and differential scanning calorimetry tests, possessing 16 K broad thermal hysteresis. Multiple-temperature powder X-ray diffraction analysis further proves the phase-transition behavior of compound 1. Moreover, compound 1 exhibits a significant steplike dielectric response near Tc, revealing that it can be deemed to be a promising dielectric switching material. The variable-temperature fluorescence experiments show distinct photoluminescence (PL) changes of compound 1. Further investigation and calculation disclose that the fluorescence lifetime of compound 1 can reach as long as 55.46 µs, indicating that it can be a potential PL material. All of these researches contribute a substitutable avenue in the design and construction of neoteric phase-transition compounds combining high Curie temperature and PL properties.

18.
Artif Organs ; 45(8): E293-E303, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33527366

RESUMEN

An artificial anal sphincter is a device to help patients with fecal incontinence rebuild the ability to control the excrement through the anus. In this article, an artificial anal sphincter based on a novel clamping mechanism (AASNCM) is proposed to improve the safety and reliability. The AASNCM, which is powered by a transcutaneous energy transfer system, consists of a novel clamping mechanism, a receiving coil and a control unit. According to design requirements, the novel clamping mechanism model was established. After that, its kinematics and dynamics were analyzed. The results of force tests on the prototype AASNCM show that the maximum values of clamping force and expanding force are 15.859 and 31.029 N, respectively. Comparing the experimental results with theoretical analysis, a good match can be concluded. Finally, in vitro experiments were conducted, and have verified the safety and reliability of the proposed AASNCM.


Asunto(s)
Canal Anal/fisiopatología , Canal Anal/cirugía , Órganos Artificiales , Incontinencia Fecal/cirugía , Diseño de Prótesis , Implantación de Prótesis/métodos , Humanos , Técnicas In Vitro
19.
Am J Emerg Med ; 44: 366-372, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32389399

RESUMEN

OBJECTIVE: To evaluate the prognostic value of routine coagulation tests for patients with heat stroke. METHODS: This was a multi-center retrospective study. Patients who arrived at the hospital <24 h after the onset of Heat Stroke (HS) were included. The routine coagulation variables were detected within 24 h after the onset, including the lowest platelet count (PLC). RESULTS: 60-day mortality rate was 20.9%. The median Prothrombin Time-International Normalized Ratio (PT-INR) of the non-surviving patients was significantly higher than that of the survivors (P < 0.01). The median Activated Partial Thromboplastin Time (APTT) in non-surviving patients was significantly higher than in the surviving patients (P < 0.01). A Cox regression analysis revealed that 60-day mortality was associated with PT-INR (P = 0.032) and APTT (P = 0.004). The optimal PT-INR point for predicting 60-day mortality rate was 1.7. The optimal APTT point for predicting 60-day mortality was 51.45. Patients with increased PT-INR (≥1.7) levels had, overall, a significantly reduced survival time (P < 0.01). Patients with elevated APTT (≥51.45) also had a decrease in survival time (P < 0.01). The prognostic scoring, with increased PT-INR (≥1.7) and prolonged APTT (≥51.45) at one point each, was also demonstrated to be useful in predicting 60-day mortality. Patients whose temperature fell to 38.9 °C within 30 min had significantly lower levels of PT-INR and APTT within 24 h than those who took longer to cool down. CONCLUSIONS: A prolonged APTT and elevated PT-INR within 24 h are independent prognostic factors of 60-day mortality in HS.


Asunto(s)
Pruebas de Coagulación Sanguínea , Golpe de Calor/sangre , Golpe de Calor/mortalidad , Adulto , China/epidemiología , Femenino , Humanos , Relación Normalizada Internacional , Masculino , Tiempo de Tromboplastina Parcial , Pronóstico , Tiempo de Protrombina , Estudios Retrospectivos , Tasa de Supervivencia
20.
J Perianesth Nurs ; 36(6): 685-689, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34384688

RESUMEN

PURPOSE: A wireless and wearable axillary thermometer (iThermonitor) has been validated for perioperative core temperature monitoring in adults. The purpose of this study was to evaluate its accuracy in pediatrics having non-cardiac surgery. DESIGN: Prospective observational study. METHODS: From January 2019 to December 2019, 70 children aged younger than 14 years undergoing surgery in a tertiary hospital were selected. Pairs of esophageal temperatures (TEso), rectal temperatures (TRec), and axillary temperatures monitored by the iThermonitor (TiTh) were collected every 5 min during surgery. Taking TEso as reference, the bias between TEso and TiTh and the proportion of bias within ±0.5°C were calculated. Bland-Altman method was used to analyze the 95% of limits of agreement (LOA) between TiTh and TEso. The same analyses were done for TRec. FINDINGS: A total of 2232 pairs of temperatures were collected. The bias (mean ± SD) between TiTh and TEso was -0.07 °C ± 0.25°C, and 95% LOA was -0.07°C ± 0.50°C. The proportion of bias within ±0.5°C accounted for 96% (95% Confidence Interval [CI], 92-98%). Higher bias and 95% LOA, and lower proportion of bias within ± 0.5°C were found between TRec and TEso than those between TiTh and TEso. CONCLUSION: During pediatric non-cardiac surgery, axillary temperature derived from iThermonitor is in good agreement with esophageal temperature and can be used as an alternative to core temperature.


Asunto(s)
Pediatría , Termómetros , Adulto , Axila , Temperatura Corporal , Niño , Humanos , Temperatura
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