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1.
Psychooncology ; 2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34343380

RESUMO

OBJECTIVES: To elucidate changes in depressive symptoms after bereavement and the impact of pre-loss resilience on such changes and on the extent of complicated grief and posttraumatic growth. METHODS: Prospective cohort surveys were provided to family caregivers of patients with cancer in four palliative care units (PCUs) before and after bereavement. Pre-loss Connor-Davidson Resilience Scale scores, pre- and post-loss Patient Health Questionnaire-9 scores, post-loss Brief Grief Questionnaire scores, and the expanded Posttraumatic Growth Inventory scores were determined. RESULTS: Out of 186 bereaved family caregivers, 71 (38.2%) responses were analyzed, among which 47% pre-loss and 15% post-loss responses suggested to be a high risk for major depressive disorder (MDD). Approximately 90% of family caregivers at a high risk for post-loss MDD were already at a high risk for pre-loss MDD. Even after adjustment of the background variables as covariates, the interaction effect between family caregivers' pre-loss depressive symptoms and resilience on post-loss depressive symptoms was observed (F = 7.29; p < 0.01). Moreover, pre-loss resilience was not associated with other bereavement outcome measures. CONCLUSIONS: Among family caregivers of patients with cancer in PCUs, 47% and 15% had high risk for MDD before and after bereavement, respectively. Moreover, pre-loss resilience mitigated post-loss depressive symptoms among family caregivers who had high risk for MDD before bereavement. However, considering the study's small sample size, further research is needed.

2.
Microscopy (Oxf) ; 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34155519

RESUMO

Sulfide-based solid electrolytes exhibiting high ionic conductivity are indispensable battery material for next-generation all-solid-state batteries. However, they have a major drawback in their low chemical stability in air. When exposed to H2O or O2 gas, toxic H2S is generated, and their ionic conductivity considerably declines. However, their degradation mechanism caused by air exposure has not been understood yet. To clarify the degradation process, in this study, we developed a transmission electron microscope (TEM) system to evaluate the air stability of battery materials. Using a vacuum transfer double-tilt TEM holder with a gas-flow system, the in situ observation of the degradation process was conducted for a sulfide-based Li4SnS4 glass ceramic under an air-flow environment. Consequently, electron diffraction patterns and TEM images could clearly capture morphological changes and amorphization process caused by air exposure. Moreover, based on the analysis of electron diffraction patterns, Li4SnS4 is likely to decompose because of the reaction with H2O in air. Therefore, this airtight and air-flow TEM system should be effective in clarifying the process of the deterioration of sulfur-based solid electrolytes during exposure to air.

3.
ACS Appl Mater Interfaces ; 13(4): 5000-5007, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33470786

RESUMO

The application of lithium metal as a negative electrode in all-solid-state batteries shows promise for optimizing battery safety and energy density. However, further development relies on a detailed understanding of the chemo-mechanical issues at the interface between the lithium metal and solid electrolyte (SE). In this study, crack formation inside the sulfide SE (Li3PS4: LPS) layers during battery operation was visualized using in situ X-ray computed tomography (X-ray CT). Moreover, the degradation mechanism that causes short-circuiting was proposed based on a combination of the X-ray CT results and scanning electron microscopy images after short-circuiting. The primary cause of short-circuiting was a chemical reaction in which LPS was reduced at the lithium interface. The LPS expanded during decomposition, thereby forming small cracks. Lithium penetrated the small cracks to form new interfaces with fresh LPS on the interior of the LPS layers. This combination of reduction-expansion-cracking of LPS was repeated at these new interfaces. Lithium clusters eventually formed, thereby generating large cracks due to stress concentration. Lithium penetrated these large cracks easily, finally causing short-circuiting. Therefore, preventing the reduction reaction at the interface between the SE and lithium metal is effective in suppressing degradation. In fact, LPS-LiI electrolytes, which are highly stable to reduction, were demonstrated to prevent the repeated degradation mechanism. These findings will promote all-solid-state lithium-metal battery development by providing valuable insight into the design of the interface between SEs and lithium, where the selection of a suitable SE is vital.

4.
J Palliat Med ; 24(9): 1284-1290, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33470878

RESUMO

Background: The concept of cost-effectiveness is necessary for optimal utilization of limited health care resources. However, few studies have assessed the cost-effectiveness of palliative care using quality-adjusted life years (QALYs), considered common outcomes in health economics. Objective: We aimed to perform a cost-effectiveness analysis of palliative care for terminal cancer patients by using QALYs. Design: A retrospective cohort study was performed. Setting/Patients: We included 401 patients with stage IV cancer, who were hospitalized and died at a Japanese general hospital during the period April 2014 to March 2019. Methods: Using the hospital database, we compared the total admission costs and QALYs based on pain levels of patients admitted to the palliative care (PC) department with those of patients admitted to other usual care (UC) departments. Patients in each group were matched through propensity scores to reduce bias. Bootstrapping estimated the 95% confidence intervals (95% CIs) and the probability that PC was more cost-effective than UC. Results: After matching, 128 patients in each group were selected. Converting 1 U.S. dollar (USD) to 100 Japanese yen, PC reduced mean total admission costs by 1732 USD (95% CI: 1584-1879) and improved mean health benefits by 0.0028 QALYs (95% CI: 0.0025-0.0032) compared with UC. Based on the Japanese cost-effectiveness threshold, there was an 82% probability that PC was more cost-effective than UC. Conclusions: Our results indicated that admission of terminal cancer patients to the PC department was associated with improvement in cost-effectiveness. This finding could support the introduction of palliative care for terminal cancer patients. Our study was approved at St. Luke's International University (receipt number 18-R061 and at the Graduate School of Pharmaceutical Sciences, The Univesity of Tokyo (receipt number 31-29).


Assuntos
Neoplasias , Cuidados Paliativos , Análise Custo-Benefício , Hospitais Gerais , Humanos , Japão , Neoplasias/terapia , Anos de Vida Ajustados por Qualidade de Vida , Estudos Retrospectivos
5.
ACS Omega ; 5(40): 26287-26294, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33073156

RESUMO

All-solid-state lithium batteries using inorganic sulfide solid electrolytes have good safety properties and high rate capabilities as expected for a next-generation battery. Presently, conventional preparation methods such as mechanical milling and/or solid-phase synthesis need a long time to provide a small amount of the product, and they have difficult in supplying a sufficient amount to meet the demand. Hence, liquid-phase synthesis methods have been developed for large-scale synthesis. However, the ionic conductivity of sulfide solid electrolytes prepared via liquid-phase synthesis is typically lower than that prepared via solid-phase synthesis. In this study, we have controlled three factors: (1) shaking time, (2) annealing temperature, and (3) annealing time. The factors influencing lithium ionic conductivity of Li3PS4 prepared via liquid-phase synthesis were quantitatively evaluated using high-energy X-ray diffraction (XRD) measurement coupled with pair distribution function (PDF) analysis. It was revealed from PDF analysis that the amount of Li2S that cannot be detected by Raman spectroscopy or XRD decreased the ionic conductivity. Furthermore, it was revealed that the ionic conductivity of Li3PS4 is dominated by other parameters, such as remaining solvent in the sample and high crystallinity of the sample.

6.
ACS Nano ; 14(9): 10966-10975, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32806070

RESUMO

The rising global human population and increased environmental stresses require a higher plant productivity while balancing the ecosystem using advanced nanoelectronic technologies. Although multifunctional wearable devices have played distinct roles in human healthcare monitoring and disease diagnosis, probing potential physiological health issues in plants poses a formidable challenge due to their biological complexity. Herein an integrated multimodal flexible sensor system is proposed for plant growth management using stacked ZnIn2S4(ZIS) nanosheets as the kernel sensing media. The proposed ZIS-based flexible sensor can not only perceive light illumination at a fast response (∼4 ms) but also monitor the humidity with a perdurable steady performance that has yet to be reported elsewhere. First-principles calculations reveal that the tunneling effect dominates the current model associated with humidity response. This finding guides the investigation on the plant stomatal functions by measuring plant transpiration. Significantly, dehydration conditions are visually recorded during a monitoring period (>15 days). This work may contribute to plant-machine biointerfaces to precisely manage plant health status and judiciously utilize limited resources.


Assuntos
Ecossistema , Dispositivos Eletrônicos Vestíveis , Atenção à Saúde , Humanos , Umidade , Monitorização Fisiológica
7.
Phys Chem Chem Phys ; 22(23): 13271-13276, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32500881

RESUMO

The reaction uniformity of LiCoO2 composite positive electrodes in all-solid-state cells was compared quantitatively by investigating the Raman band shifts corresponding to the state-of-charge (SOC) of LiCoO2. The quantitative SOC analysis was conducted using the Raman imaging data of composite electrodes with smaller or larger solid electrolytes. The electrodes exhibited different reaction uniformity although the cells showed similar initial charge capacities and average SOC. In the case of larger solid electrolytes, most LiCoO2 particles showed higher or lower SOC than the average SOC, and lower battery performance. The quantitative analysis of SOC in each LiCoO2 electrode demonstrated that a variable SOC outside the average SOC resulted in larger irreversible capacity and lower rate performance. The quantitative SOC analysis newly developed in the present study is a useful technique for designing composite electrodes showing higher battery performance.

8.
ACS Appl Mater Interfaces ; 12(26): 29228-29234, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32510202

RESUMO

Long-lasting all-solid-state batteries can be achieved by preventing side reactions in the composite electrodes comprising electrode active materials and solid electrolytes. Typically, the battery performance can be enhanced through the use of robust solid electrolytes that are resistant to oxidation and decomposition. In this study, the thermal stability of sulfide solid electrolytes Li3PS4 and Li4SnS4 toward oxide positive electrode active materials was estimated by investigating the occurrence of side reactions at the electrolyte-electrode interfaces when the composite electrodes are heated in an accelerated aging test: Li4SnS4 showed higher thermal stability because of the suppression of the substitution reaction between S and O. Moreover, thermally stable sulfide solid electrolytes are amenable to an improved cell construction process. The sintering (pelletizing and subsequent heating) of the composite electrodes with Li4SnS4 as the solid electrolyte allowed the manufacture of dense electrodes that exhibited increased ionic conductivity, thereby enhancing the battery performance.

9.
Sci Adv ; 6(25): eaax7236, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32596439

RESUMO

An all-solid-state lithium battery using inorganic solid electrolytes requires safety assurance and improved energy density, both of which are issues in large-scale applications of lithium-ion batteries. Utilization of high-capacity lithium-excess electrode materials is effective for the further increase in energy density. However, they have never been applied to all-solid-state batteries. Operational difficulty of all-solid-state batteries using them generally lies in the construction of the electrode-electrolyte interface. By the amorphization of Li2RuO3 as a lithium-excess model material with Li2SO4, here, we have first demonstrated a reversible oxygen redox reaction in all-solid-state batteries. Amorphous nature of the Li2RuO3-Li2SO4 matrix enables inclusion of active material with high conductivity and ductility for achieving favorable interfaces with charge transfer capabilities, leading to the stable operation of all-solid-state batteries.

10.
ACS Appl Mater Interfaces ; 12(20): 22798-22803, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32281781

RESUMO

The dendritic growth of the Li metal through a separator is a serious issue for the development of rechargeable Li metal batteries in which the Li metal is used as the negative electrode. Several methods have been investigated for this issue; however, it has not been completely solved until now. The all-solid-state battery (ASSB) system is one of the most powerful methods for practical use of the Li metal negative electrode because the solid-state electrolyte (SSE) can mechanically block the dendritic growth of Li metal. ASSBs are pressed for reducing interfacial resistance between electrode active materials and SSE; therefore, the high mechanical strength of SSE results in the growth of Li metal through voids among SSE particles, leading to internal short circuit. In this study, a negative electrode current collector with microsized pores where the Li metal could be preferentially deposited was designed and prepared by coating Au or Ni on a commercially available membrane filter with 8 µm diameter pores. The Li metal deposition/dissolution behavior in the pores of the Au- or Ni-coated membrane filter under galvanostatic conditions was discussed based on scanning electron microscopy images. Consequently, the Li metal deposition occurred in the pores during charging and the deposited Li dissolved from the pores during discharging. Moreover, it was found that there were two modes in the Li deposition in the pores, and the deposition modes could be controlled by coating material and current density.

11.
J Cardiol ; 76(2): 177-183, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32199753

RESUMO

BACKGROUND: Although recent attention to palliative care for patients with cardiovascular diseases has been increasing, there are no specific recommendations on detailed palliative care practices. We proceed on a discussion of the appropriateness and applicability of potential quality indicators for acute cardiovascular diseases according to our previous systematic review. METHODS: We created a multidisciplinary panel of 20 team members and 7 external validation clinicians composed of clinical cardiologists, a nutritionist, a physiotherapist, a clinical psychologist, a critical and emergent care specialist, a catheterization specialist, a primary care specialist, a palliative care specialist, and nurses. After crafting potential indicators, we performed a Delphi rating, ranging from "1 = minimum" to "9 = maximum". The criterion for the adoption of candidate indicators was set at a total mean score of seven or more. Finally, we subcategorized these indicators into several domains by using exploratory factor analysis. RESULTS: Sixteen of the panel members (80%) were men (age, 49.5 ± 13.7 years old). Among the initial 32 indicators, consensus was initially reached on total 23 indicators (71.8%), which were then summarized into 21 measures by selecting relatively feasible time variations. The major domains were "symptom palliation" and "supporting the decision-making process". Factor analysis could not find optimal model. Narratively-developed seven sub-categories included "presence of palliative care team", "patient-family relationship", "multidisciplinary team approach", "policy of approaching patients", "symptom screening and management", "presence of ethical review board", "collecting and providing information for decision-maker", and "determination of treatment strategy and the sharing of the care team's decision". CONCLUSION: In this study we developed 21 quality indicators, which were categorized into 2 major domains and 7 sub-categories. These indicators might be useful for many healthcare providers in the initiation and enhancement of palliative care practices for acute cardiovascular diseases in Japan.


Assuntos
Doenças Cardiovasculares/terapia , Cuidados Paliativos/normas , Indicadores de Qualidade em Assistência à Saúde , Adulto , Consenso , Técnica Delfos , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade
12.
J Phys Chem Lett ; 11(3): 900-904, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31951133

RESUMO

The dynamic changes of ionic conduction path in the cross-sectional graphite composite electrodes of bulk-type all-solid-state lithium batteries have been monitored using operando confocal microscopic observations for color changes of graphite in response to their stage structures. The ionic conduction path decreased in the cross-sectional direction as cycle numbers increased, with simultaneous capacity degradation. The local reactivity of lithiation and delithiation was evaluated by image analysis considering state-of-charge (SOC) values. Electrode thickness changes were examined from the confocal microscope images obtained in the operando observations. The results revealed that voids and cracks were formed during cycle tests and that the thickness gradually increased. These cracks and voids were one of the main contributors to the limitation of ionic conduction paths in the depth direction. Operando microscopic observation and subsequent image analysis elucidated not only the morphological changes of active materials but also the differences in local SOC changes in the electrode.

13.
Sci Rep ; 8(1): 15613, 2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30353123

RESUMO

Lithium-ion batteries are widely used as a power source for portable equipment. However, the use of highly flammable organic solvents in the liquid electrolyte component in these batteries presents a serious safety concern. In this study, the thermal stability of battery cathodes comprising LiNi1/3Mn1/3Co1/3O2 (NMC) and LiPF6-based electrolyte solutions have been investigated using transmission electron microscopy (TEM) and differential scanning calorimetry (DSC) methods. Ex situ TEM measurements revealed that significant structural change occurred in the charged NMC composite after heating at a temperature above the exothermal peaks. It was found that LiF nanocrystallites precipitated in LiPF6 and that a number of nanoscale stacking faults developed in the [Formula: see text] layered structure of NMC. The results suggested that the decomposition reaction of LiPF6 and the structural change of NMC were directly associated with the exothermic reaction in the liquid electrolyte-based NMC electrode composite.

14.
Inorg Chem ; 57(16): 9925-9930, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-30091598

RESUMO

A new crystalline lithium-ion conducting material, Li4SnS4 with an ortho-composition, was prepared by a mechanochemical technique and subsequent heat treatment. Synchrotron X-ray powder diffraction was used to analyze the crystal structure, revealing a space group of P63/ mmc and cell parameters of a = 4.01254(4) Å and c = 6.39076(8) Å. Analysis of a heat-treated hexagonal Li4SnS4 sample revealed that both lithium and tin occupied either of two adjacent tetrahedral sites, resulting in fractional occupation of the tetrahedral site (Li, 0.375; Sn, 0.125). The heat-treated hexagonal Li4SnS4 had an ionic conductivity of 1.1 × 10-4 S cm-1 at room temperature and a conduction activation energy of 32 kJ mol-1. Moreover, the heat-treated Li4SnS4 exhibited a higher chemical stability in air than the Li3PS4 glass-ceramic.

15.
ACS Appl Mater Interfaces ; 10(23): 19605-19614, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29775274

RESUMO

All-solid-state sodium batteries using Na3Zr2Si2PO12 (NASICON) solid electrolytes are promising candidates for safe and low-cost advanced rechargeable battery systems. Although NASICON electrolytes have intrinsically high sodium-ion conductivities, their high sintering temperatures interfere with the immediate development of high-performance batteries. In this work, sintering-free NASICON-based composites with Na3PS4 (NPS) glass ceramics were prepared to combine the high grain-bulk conductivity of NASICON and the interfacial formation ability of NPS. Before the composite preparation, the NASICON/NPS interfacial resistance was investigated by modeling the interface between the NASICON sintered ceramic and the NPS glass thin film. The interfacial ion-transfer resistance was very small above room temperature; the area-specific resistances at 25 and 100 °C were 15.8 and 0.40 Ω cm2, respectively. On the basis of this smooth ion transfer, NASICON-rich (70-90 wt %) NASICON-NPS composite powders were prepared by ball-milling fine powders of each component. The composite powders were well-densified by pressing at room temperature. Scanning electron microscopy observation showed highly dispersed sub-micrometer NASICON grains in a dense NPS matrix to form closed interfaces between the oxide and sulfide solid electrolytes. The composite green (unfired) compacts with 70 and 80 wt % NASICON exhibited high total conductivities at 100 °C of 1.1 × 10-3 and 6.8 × 10-4 S cm-1, respectively. An all-solid-state Na15Sn4/TiS2 cell was constructed using the 70 wt % NASICON composite electrolyte by the uniaxial pressing of the powder materials, and its discharge properties were evaluated at 100 °C. The cell showed the reversible capacities of about 120 mAh g-1 under the current density of 640 µA cm-2. The prepared oxide-based composite electrolytes were thus successfully applied in all-solid-state sodium rechargeable batteries without sintering.

16.
Sci Rep ; 8(1): 6214, 2018 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-29670203

RESUMO

Sulfide-based all-solid-state lithium batteries are a next-generation power source composed of the inorganic solid electrolytes which are incombustible and have high ionic conductivity. Positive electrode composites comprising LiNi1/3Mn1/3Co1/3O2 (NMC) and 75Li2S·25P2S5 (LPS) glass electrolytes exhibit excellent charge-discharge cycle performance and are promising candidates for realizing all-solid-state batteries. The thermal stabilities of NMC-LPS composites have been investigated by transmission electron microscopy (TEM), which indicated that an exothermal reaction could be attributed to the crystallization of the LPS glass. To further understand the origin of the exothermic reaction, in this study, the precipitated crystalline phase of LPS glass in the NMC-LPS composite was examined. In situ TEM observations revealed that the ß-Li3PS4 precipitated at approximately 200 °C, and then Li4P2S6 and Li2S precipitated at approximately 400 °C. Because the Li4P2S6 and Li2S crystalline phases do not precipitate in the single LPS glass, the interfacial contact between LPS and NMC has a significant influence on both the LPS crystallization behavior and the exothermal reaction in the NMC-LPS composites.

17.
ACS Omega ; 3(5): 5453-5458, 2018 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31458750

RESUMO

Solid electrolytes with compositions of (100 - x)(0.75Li2S·0.25P2S5)·xLiBH4 (mol %, 0 ≤ x ≤ 100) were mechanochemically prepared from the 75Li2S·25P2S5 (mol %) glass and LiBH4 crystal. The samples with x ≥ 43 have crystalline phases and those with x ≤ 33 formed a glassy phase. The crystalline phase was identified as argyrodite Li6PS5(BH4). The x = 50 sample formed a crystalline phase and demonstrated a high lithium-ion conductivity of 1.8 × 10-3 S cm-1 at 25 °C with an activation energy of 16 kJ·mol-1. The argyrodite-type crystal with a BH4 - anion that occupies the halide site is a novel and promising solid electrolyte.

18.
Sci Rep ; 7(1): 4142, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28646212

RESUMO

There are two types of solid electrolytes which has been recently expected to be applied to all-solid-state batteries. One is the glasses characterized by an amorphous state. The other is the glass ceramics containing crystalline in an amorphous matrix. However, the non-crystalline state of glasses and glass ceramics is still an open question. It has been anticipated that sea-island and core-shell structures including crystalline nanoparticles have been proposed as candidate models for glass ceramics. Nevertheless, no direct observation has been conducted so far. Here we report the non-crystalline state of Li2S-P2S5 glasses and glass ceramics, and the crystallization behavior of the glasses during heating via direct transmission electron microscopy (TEM) observation. High resolution TEM images clearly revealed the presence of crystalline nanoparticles in an amorphous region. Eventually we suggest that the precipitation and connection of crystalline nanoparticles in an amorphous matrix are key to achieving high ionic conductivity.

19.
J Cardiol ; 70(4): 335-341, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28427868

RESUMO

In spite of the increasing interest in palliative care for heart disease, data on the detailed methods of palliative care and its efficacy specifically in heart disease are still lacking. A structured PubMed literature review revealed no quality indicators of palliative care in heart disease. Therefore, we performed a narrative overview of the potential quality indicators in heart disease by reviewing previous literature concerning quality indicators in cancer patients. We summarize seven potential categories of quality indicators in heart disease: (1) presence and availability of a palliative care unit, palliative care team, and outpatient palliative care; (2) human resources such as number of skilled staff; (3) infrastructure; (4) presence and frequency of documentation or family survey; (5) patient-reported outcome measure (PROM) data and disease-specific patient quality of life such as The Kansas City Cardiomyopathy Questionnaire (KCCQ); (6) questionnaires and interviews about the quality of palliative care after death, including bereaved family surveys; and (7) admission-related outcomes such as place of death and intensive care unit length of stay. Although detailed measurements of palliative care quality have not been validated in heart disease, many indicators developed in cancer patients might also be applicable to heart disease. This new categorization might be useful to determine quality indicators in heart disease patients.


Assuntos
Cardiopatias/terapia , Cuidados Paliativos/normas , Indicadores de Qualidade em Assistência à Saúde , Humanos , Medidas de Resultados Relatados pelo Paciente
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