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We investigated methods for cryopreserving sperm from the endangered gudgeon, Microphysogobio rapidus, by examining the effects of cryoprotective agent (CPA) concentration, diluent, and dilution ratio on post-thaw sperm quality. The quality of frozen sperm was evaluated in terms of motility and kinematic parameters, viability, DNA damage, and fertilization rate. We evaluated methanol, glycerol, dimethyl sulfoxide (DMSO), and ethylene glycol as CPAs. Sperm motility, velocity, and viability were significantly higher when methanol was used as the CPA (p < 0.05). The diluents tested were Ringer's solution, Kurokura's Extender, Common Carp Sperm Extender (CCSE), and buffered sperm motility-inhibiting saline solution (BSMIS); post-thaw motility was highest when Ringer's solution was used as the diluent. Next, various quantities of methanol were combined with Ringer's solution to identify the optimal dose of methanol. The dilution ratios tested ranged from 1:1 to 1:7. Cryopreserved sperm was thawed at 20 °C for 15 s. The use of 10% methanol with Ringer's solution at a dilution ratio of 1:5 resulted in the highest post-thaw sperm motility, viability, and velocity including VAP, VCL, and VSL. Post-thaw sperm showed significantly greater DNA damage than the control (fresh sperm) (p < 0.05). The fertilization rate was highest with fresh sperm (p < 0.05), followed by sperm frozen with 10% methanol + Ringer's solution. We recommend that the best way to preserve sperm in the studied species is to use a combination of Ringer's solution and 10% methanol at a 1:5 dilution ratio. Our findings will facilitate the artificial fertilization of M. rapidus.
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Criopreservación , Crioprotectores , Cyprinidae , Dimetilsulfóxido , Metanol , Preservación de Semen , Motilidad Espermática , Espermatozoides , Animales , Masculino , Criopreservación/métodos , Criopreservación/veterinaria , Crioprotectores/farmacología , Preservación de Semen/métodos , Preservación de Semen/veterinaria , Motilidad Espermática/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Cyprinidae/fisiología , Metanol/farmacología , Dimetilsulfóxido/farmacología , Glicerol/farmacología , Glicol de Etileno/farmacología , Daño del ADN/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , FemeninoRESUMEN
The concept of a lithiophilic electrode proves inadequate in describing carbon-based electrode materials due to their substantial mismatch in surface energy with lithium metal. However, their notable capacity for lithium chemisorption can increase active lithium concentration required for nucleation and growth, thereby enhancing the electrochemical performance of lithium metal anodes (LMAs). In this study, we elucidate the effects of the supersaturated electrode which has high active lithium capacity around equilibrium lithium potential on LMAs through an in-depth electrochemical comparison using two distinct carbon electrode platforms with differing carbon structures but similar two-dimensional morphologies. In the supersaturated electrode, both the dynamics and thermodynamic states involved in lithium nucleation and growth mechanisms are significantly improved, particularly under continuous current supply conditions. Furthermore, the chemical structures of the solid-electrolyte-interface layers (SEIs) are greatly influenced by the elevated surface lithium concentration environment, resulting in the formation of more conductive lithium-rich SEI layers. The improved dynamics and thermodynamics of surface lithium, coupled with the formation of enhanced SEI layers, contribute to higher power capabilities, enhanced Coulombic efficiencies, and improved cycling performances of LMAs. These results provide new insight into understanding the enhancements in heterogeneous lithium nucleation and growth kinetics on the supersaturated electrode.
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Pyroprotein-based carbon materials produced by heat-treating silk proteins have many potential applications in electronic devices, such as electronic textiles. To further develop potential electronic devices using these pyroproteins, the charge transport mechanism has to be verified. However, the electrical characteristics of the pyroproteins have not been reported yet. In this study, the temperature-dependent charge transport behavior of pyroprotein-based electronic yarns prepared from commercial silks (e-CS yarns) is investigated with respect to various heat treatment temperatures (HTT, 800, 1000, 1200, and 1400 °C). The linear current-voltage properties are shown at a low bias of 100 nA from 9 K to 300 K. The temperature-dependent resistivity of the e-CS yarns can be clearly described by the crossover of 3-dimensional Mott variable range hopping and fluctuation-induced tunneling conduction at the crossover temperature (Tc). These Tc factors are significantly different, due to the structural modulation of the e-CS yarns depending on the HTT, and are characterized by Raman spectroscopy, X-ray diffraction, and transmission electron microscopy. This study is expected to provide a better understanding of the electrical properties of pyroproteins.
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Conductividad Eléctrica , Seda/química , Textiles , Electrónica , Pirólisis , TemperaturaRESUMEN
We report on an electronic structure change of single-walled carbon nanotube (SWNT) on hexagonal boron nitride due to electron doping via high-pressure H2 exposure. The fractional coverage of hydrogenated carbon atom is estimated to be at least θ = 0.163 from the in situ I ds-V g measurements of the release process. Raman spectroscopy and x-ray photoelectron spectroscopy were carried out to support the in situ electrical measurements. In particular, we used the dissociative Langmuir-type model to yield the desorption coefficient k des by fitting it to the in situ electrical data. Finally, we applied this hydrogenation method to the SWNT network on the commercial Si/SiO2 substrate to open the possibility of the scalable n-type semiconducting SWNT FETs.
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Many studies on flexible strain and pressure sensors have been reported due to growing interest in wearable devices for healthcare purposes. Here, we present flexible pressure and strain (motion) sensors prepared with only graphene oxide (GO) and commercial silk fabrics and yarns. The pressure sensors were fabricated by simply dipping the silk fabric into GO solution followed by applying a thermal treatment at 400 °C to obtain reduced GO (rGO). The pressure sensors were made from rGO-coated fabrics, which were stacked in three, five, and seven layers. A super-sensitivity of 2.58 × 103 kPa-1 at low pressure was observed in the seven-layer pressure sensor. The strain sensors were obtained from rGO-coated twisted silk yarns whose gauge factor was 0.307. Although this value is small or comparable to the values for other sensors, it is appropriate for motion sensing. The results of this study show a cost-effective and simple method for the fabrication of pressure and motion sensors with commercial silk and GO.
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Electronic textile-based gas sensors with a high response for NO2 gas were fabricated using reduced graphene oxide (rGO)-coated commercial cotton fabric (rGOC). Graphene oxide (GO) was coated on cotton fabric by simply dipping the cotton into a GO solution. To investigate the relationship between the degree of reduction and the sensing response, the GO-coated fabrics were thermally reduced at various temperatures (190, 200, 300, and 400 °C). The change in the amount of oxygen functional groups on the rGOCs was observed by x-ray photoelectron spectroscopy, Raman spectroscopy, and x-ray diffraction patterns. The maximum sensing response of 45.90 % at 10 ppm of NO2 gas at room temperature was exhibited by the rGOC treated at 190 °C, which was the lowest heat-treatment temperature. The high response comes from the greater amount of oxygen functional groups compared to other rGOC samples, and the tubular structure of the cotton.
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Intermediate-term preservation of sperm assists the reproductive management of fish spermatozoa; however, no information is available on sperm of the spotted halibut, Verasper variegatus. We aimed to identify the optimum diluents, temperatures, dilution ratios, antibiotics, and antioxidants for sperm motility and cell viability. The diluents evaluated were marine fish Ringer's solution (MFRS), Stein's solution, 300 mM sucrose, and 300 mM glucose (diluted 1:1 [sperm: diluent], 1:2, 1:4, and 1:10 and stored at 0, 2, 4, and 6 °C). Neomycin and gentamycin (100, 200, 400, and 800 mg/L) and antioxidants (Mito-TEMPO [0, 25, 50, 75, 100, 125, 150, 175, and 200 µM], reduced glutathione [0, 2, 4, 6, 8, and 10 mM], and trehalose [0, 50, 100, 150, 200, and 250 mM]) were assessed in terms of sperm preservation. The most effective condition for cold storage of spotted halibut sperm was Stein's solution at a dilution ratio of 1:4 at 2 °C, with a combination of neomycin 800 mg/L and 250 mM trehalose that showed spermatozoa motility of > 43% after 60 days. These storage conditions will be valuable for spotted halibut hatcheries.
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The roughscale sole, Clidoderma asperrimum is categorized as an endangered species. Sperm freezing is essential for preserving gametes. This study examined the CPA concentration, diluent, dilution ratio, and thawing temperature to design a sperm cryopreservation protocol for roughscale sole. The variables examined included sperm motility and kinematics, cell survival, fertilization, and DNA fragmentation. Sperm motility parameters were assessed via computer-assisted sperm analysis using a CEROS II instrument. Cell survival rate and DNA damage were assessed using the Cell Counting Kit-8 and single-cell gel electrophoresis assay, respectively. Sperm preservation was tested using several CPAs, including ethylene glycol, dimethyl sulfoxide (DMSO), glycerol, propylene glycol, and methanol. The diluents tested were 300 mM sucrose, 300 mM glucose, Stein's solution, Ringer's solution, and Hank's solution. The optimal conditions for sperm cryopreservation were 10% DMSO + Stein's solution. After thawing, sperm motility was highest with a 1:1 dilution ratio (sperm to CPA + diluent), at 69.20 ± 0.32%; thawing at 10 °C was optimal for post-thaw motility (72.03 ± 0.95%). The highest fertilization rate (40.00 ± 1.22%) was obtained using DMSO. The fresh sperm had the lowest tail DNA, followed by 10% DMSO + Stein's solution. The developed cryopreservation methods can be used in roughscale sole hatcheries.
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BACKGROUND: In trauma patients, bleeding is an immediate major concern. At the same time, there are few cases of acute vascular occlusion after blunt trauma, and it is unclear what assessment and diagnosis should be considered for these cases. Herein, we describe a patient diagnosed with antiphospholipid syndrome after a hypercoagulable workup for acute renal and splenic vascular occlusion due to blunt trauma. CASE SUMMARY: A 20-year-old man was admitted to the emergency department with abdominal pain after hitting a tree while riding a sled 10 h ago. He had no medical history. Radiological investigations revealed occlusion of the left renal artery with global infarction of the left kidney and occlusion of branches of the splenic artery with infarction of the central portion of the spleen. Attempted revascularization of the left renal artery occlusion through percutaneous transluminal angioplasty failed due to difficulty in passing the wire through the total occlusion. Considering the presence of acute multivascular occlusions in a young man with low cardiovascular risk, additional laboratory tests were performed to evaluate hypercoagulability. The results suggested a high possibility of antiphospholipid syndrome. Treatment with a subcutaneous injection of enoxaparin was started and changed to oral warfarin after two weeks. The diagnosis was confirmed, and he continued to visit the rheumatology outpatient clinic while taking warfarin. CONCLUSION: A hypercoagulable workup can be considered in trauma patients with acute multivascular occlusion, especially in young patients with low cardiovascular risk.
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An electronic textile-based NO2 gas sensor was fabricated using commercial silk and graphene oxide (GO). It showed a fast response time and excellent sensing performance, which was simply accomplished by modifying the heat-treatment process. The heat treatment was conducted at 400 °C and different heating rates of 1, 3, and 5 °C/min. Compared with our previous research, the response time significantly decreased, from 32.5 to 3.26 min, and we found that the highest response was obtained with the sensor treated at a heating rate of 1 °C/min. To find the reason for this enhanced sensing performance, the morphology, structure, and chemical composition of the reduced GO (rGO) were investigated, depending on the thermal treatment process, using scanning electron microscopy, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy. We also measured the temperature-dependent resistance of rGO, which was well described by the fluctuation-induced tunneling (FIT) model. These results revealed that the rGO thermally treated with 1 °C/min of heating rate had the largest amount of oxygen groups. This means that the oxygen functional groups play an important role in NO2 gas-sensing performance.
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In the oxidative dehydrogenation (ODH) process that converts ethylbenzene to styrene, vanadium-based catalysts, especially V2O5, are used in a CO2 atmosphere to enhance process efficiency. Here we demonstrate that the activation energy of V2O5 can be manipulated by exposure to high pressure CO2, using V2O5 nanowires (VON). The oxidation of V4+ to V5+ was observed by X-ray photoelectron spectroscopy. The ratio of V4+/V5+ which the typical comparable feature decreased 73.42%. We also found an increase in the interlayer distance in VON from 9.95 Å to 10.10 Å using X-ray diffraction patterns. We observed changes in the peaks of the stretching mode of bridging triply coordinated oxygen (V3-O), and the bending vibration of the bridging V-O-V, using Raman spectroscopy. We confirmed this propensity by measuring the CO2 pressure-dependent conductance of VON, up to 45 bar. 92.52% of decrease in the maximum conductance compared with that of the pristine VON was observed. The results of this study suggest that ODH process performance can be improved using the VON catalyst in a high pressure CO2 atmosphere.
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We report improved conductance by reducing the work function via incorporation of hydrogen into VO2 nanowires. The VO2 nanowires were prepared using the chemical vapor deposition method with V2O5 powder on silicon substrates at 850 °C. Hydrogenation was carried out using the high-pressure hydrogenation method. Raman spectroscopy confirmed that the incorporated hydrogen atoms resulted in a change in the lattice constant of the VO2 nanowires (NWs). To quantitatively measure the work function of the nanowires, Kelvin probe force microscopy (KPFM) was employed at ambient conditions. We found that the work function decreased with increasing H2 pressure, which also resulted in increased conductance. This is associated with hydrogen diffused into the VO2 that acts as a donor to elevate the Fermi level, which was also confirmed by KPFM. From these results, tuning of the reversible electrical properties of VO2 NWs, including the conductance and work function, can be achieved by incorporating hydrogen at relatively moderate temperatures.
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PURPOSE: The aim of this study was to evaluate the impact of extended resection of primary tumor on survival outcome in unresectable colorectal cancer (UCRC). METHODS: A retrospective analysis was conducted for 190 patients undergoing palliative surgery for UCRC between 1998 and 2007 at a single institution. Variables including demographics, histopathological characteristics of tumors, surgical procedures, and course of the disease were examined. RESULTS: Kaplan-Meier survival curve indicated a significant increase in survival times in patients undergoing extended resection of the primary tumor (P < 0.001). Multivariate analysis showed that extra-abdominal metastasis (P = 0.03), minimal resection of the primary tumor (P = 0.034), and the absence of multimodality adjuvant therapy (P < 0.001) were significantly associated poor survival outcome. The histological characteristics were significantly associated with survival times. Patients with well to moderate differentiation tumors that were extensively resected had significantly increased survival time (P < 0.001), while those with poor differentiation tumors that were extensively resected did not have increase survival time (P = 0.786). CONCLUSION: Extended resection of primary tumors significantly improved overall survival compared to minimal resection, especially in well to moderately differentiated tumors (survival time: extended resection, 27.8 ± 2.80 months; minimal resection, 16.5 ± 2.19 months; P = 0.002).