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1.
Heliyon ; 10(15): e33983, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39170560

RESUMEN

This study analyzes the influences of evapotranspiration or substrate moisture variation on the indoor-temperature reduction of green roofs compared to the control group. A multiple linear regression (MLR) model for the operation stage based on observation and an integrated MLR model for the planning stage based on simulation are verified. The MLR model shows 0.64 °C of the Root Mean Square Error (RMSE) in predicting the hourly difference of temperature reduction based on the measured change in evapotranspiration and air temperature. The contributions of the hourly increment of air temperature (ΔTa) and increment of evapotranspiration (ΔET) are similar to the hourly increment of temperature reduction (ΔTdif). Then, the feasibility of the integrated MLR model is demonstrated based on the evapotranspiration and substrate moisture of a green roof simulated by a hydrological model as well as the indoor-temperature reduction simulated by a building energy model, which has fair performances in capturing the heat-transfer and water-balance physical process within a green roof. The integrated MLR model shows that evapotranspiration is relatively essential, followed by substrate moisture, air temperature, and vapor pressure. Despite the modeling bias, the integrated model quantitatively relates the influential factors to temperature reduction and predicts temperature reduction with an RMSE of 1.02 °C. The integrated model can quantify the influence of irrigation on temperature reduction under various climate conditions and green roof structures. This study demonstrates the procedure of establishing the integrated model. It shows the potential of the integrated model to provide decision support on irrigation for multi-purpose optimization of green roof performances.

2.
Sci Total Environ ; 854: 158589, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36087676

RESUMEN

Drought may lead to severe and diverse impacts on agriculture, economy, and society across different regions and periods, posing predictive and adaptive challenges. In recent years, severe droughts have affected >60 million people in the Mekong River Basin (MRB). Additionally, El Niño Southern Oscillation (ENSO) episodes had distinct influences on the occurrence and intensity of drought variability in the regions. Understanding the spatiotemporal characteristics of droughts across the MRB is critical to improving management and mitigation actions. This study aims to investigate spatiotemporal drought characteristics in the MRB and their teleconnection with the ENSO. Three multiple drought indices, including the Standardized Precipitation Index (SPI) for meteorological drought, Standardized Soil Water Index (SSWI) for agricultural drought, and Standardized Runoff Index (SRI) for hydrological drought were calculated to quantify drought events, drought frequency, and drought severity. The overall patterns showed more events and larger intensity were identified by the SPI than those by the SRI or the SSWI, while the higher frequency was observed by the SRI. The Middle Mekong basins seem to experience more drought events, while higher levels of frequency and intensity of droughts were observed in the Upper Mekong Basin. The correlation analysis between ENSO index and precipitation suggested that the strongest ENSO events in Dec-Jan-Feb may result in developments of meteorological drought in Mar-Apr-May, and further led to hydrological and agricultural drought in Apr-May-Jun. Such ENSO effects had significant influences on drought variabilities in southern MRB and were insignificant in the north. The multiple drought indices show skills in identifying spatial and temporal drought characteristics from meteorological, agricultural, and hydrological perspectives, and potential for drought outlook further considering their ENSO teleconnections. The results can be applied to the development of drought monitoring methods and adaptive strategies to mitigate drought impacts through scientific and quantitative assessments.

3.
Nanomaterials (Basel) ; 12(2)2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35055273

RESUMEN

We propose a flexible capacitive pressure sensor that utilizes porous polydimethylsiloxane elastomer with zinc oxide nanowire as nanocomposite dielectric layer via a simple porogen-assisted process. With the incorporation of nanowires into the porous elastomer, our capacitive pressure sensor is not only highly responsive to subtle stimuli but vigorously so to gentle touch and verbal stimulation from 0 to 50 kPa. The fabricated zinc oxide nanowire-porous polydimethylsiloxane sensor exhibits superior sensitivity of 0.717 kPa-1, 0.360 kPa-1, and 0.200 kPa-1 at the pressure regimes of 0-50 Pa, 50-1000 Pa, and 1000-3000 Pa, respectively, presenting an approximate enhancement by 21-100 times when compared to that of a flat polydimethylsiloxane device. The nanocomposite dielectric layer also reveals an ultralow detection limit of 1.0 Pa, good stability, and durability after 4000 loading-unloading cycles, making it capable of perception of various human motions, such as finger bending, calligraphy writing, throat vibration, and airflow blowing. A proof-of-concept trial in hydrostatic water pressure sensing has been demonstrated with the proposed sensors, which can detect tiny changes in water pressure and may be helpful for underwater sensing research. This work brings out the efficacy of constructing wearable capacitive pressure sensors based on a porous dielectric hybrid with stress-sensitive nanostructures, providing wide prospective applications in wearable electronics, health monitoring, and smart artificial robotics/prosthetics.

4.
Plant Signal Behav ; 16(12): 1997513, 2021 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-34763610

RESUMEN

The ionotropic glutamate receptor (iGluR) plays an important role in neuronal signaling in animal cells. There are at least 20 glutamate receptor-like (GLR) genes in Arabidopsis thaliana. These genes are involved in seed germination, root growth, wounding response, stomata closure, etc. A recent study showed that Arabidopsis clade III glutamate receptor GLR3.7 is involved in salt stress response. We tested whether GLR3.7 is involved in abscisic acid (ABA) response. In the present study, we found that the expression of GLR3.7 was reduced by ABA treatment. Under ABA-treated condition, GLR3.7 overexpression lines exhibited significantly higher seed germination rate at 60, 72 and 84 h under ABA-treated condition. A point mutation in 14-3-3 binding site of GLR3.7 in GLR3.7-S860A overexpression lines exhibited higher seed germination inhibition under ABA-treated conditions. Our results support that GLR3.7 is involved in ABA response in Arabidopsis. In addition, Ser-860 of GLR3.7 appears to be important in ABA response.


Asunto(s)
Ácido Abscísico , Proteínas de Arabidopsis , Arabidopsis , Receptores de Glutamato , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacología , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Germinación/genética , Mutación , Receptores de Glutamato/genética , Receptores de Glutamato/metabolismo , Semillas/metabolismo
5.
Front Plant Sci ; 10: 1169, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31632419

RESUMEN

Ionotropic glutamate receptors (iGluRs) are ligand-gated cation channels that mediate fast excitatory neurotransmission in the mammalian central nervous system. In the model plant Arabidopsis thaliana, a family of 20 glutamate receptor-like proteins (GLRs) shares similarities to animal iGluRs in sequence and predicted secondary structure. However, the function of GLRs in plants is little known. In the present study, a serine site (Ser-860) of AtGLR3.7 phosphorylated by a calcium-dependent protein kinase (CDPK) was identified and confirmed by an in vitro kinase assay. Using a bimolecular fluorescence complementation and quartz crystal microbalance analyses, the physical interaction between AtGLR3.7 and the 14-3-3ω protein was confirmed. The mutation of Ser-860 to alanine abolished this interaction, indicating that Ser-860 is the 14-3-3ω binding site of AtGLR3.7. Compared with wild type, seed germination of the glr3.7-2 mutant was more sensitive to salt stress. However, the primary root growth of GLR3.7-S860A overexpression lines was less sensitive to salt stress than that of the wild-type line. In addition, the increase of cytosolic calcium ion concentration by salt stress was significantly lower in the glr3.7-2 mutant line than in the wild-type line. Moreover, association of 14-3-3 proteins to microsomal fractions was less in GLR3.7-S860A overexpression lines than in GLR3.7 overexpression line under 150 mM NaCl salt stress condition. Overall, our results indicated that GLR3.7 is involved in salt stress response in A. thaliana by affecting calcium signaling.

6.
Am J Kidney Dis ; 50(1): 124-32, 132.e1-2, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17591532

RESUMEN

BACKGROUND: People who have come close to death may report an unusual experience known as a near-death experience (NDE). This study aims to investigate NDEs and their aftereffects in dialysis patients. STUDY DESIGN: Cross-sectional study. SETTING & PARTICIPANTS: 710 dialysis patients at 7 centers in Taipei, Taiwan. PREDICTOR: Demographic characteristics, life-threatening experience, depression, and religiosity. OUTCOMES: NDE and self-perceived changes in attitudes or behaviors. MEASUREMENTS: Greyson's NDE scale, Royal Free Questionnaire, 10-Question Survey, Ring's Weighted Core Experience Index, and Beck Depression Inventory. RESULTS: 45 patients had 51 NDEs. Mean NDE score was 11.9 (95% confidence interval, 11.0 to 12.9). Out-of-body experience was found in 51.0% of NDEs. Purported precognitive visions, awareness of being dead, and "tunnel experience" were uncommon (<10%). Compared with the no-NDE group, subjects in the NDE group were more likely to be women and younger at life-threatening events. Both frequency of participation in religious ceremonies and pious religious activity correlated significantly with NDE score in patients with NDEs (P < 0.01 and P = 0.01, respectively). The NDE group reported being kinder to others (P = 0.04) and more motivated (P = 0.02) after their life-threatening events than the no-NDE group. LIMITATIONS: Determining the incidence of NDEs is dependent on self-reporting. Many NDEs occurred before the patient began long-term dialysis therapy. Causality between NDE and aftereffects cannot be inferred. CONCLUSIONS: NDE is not uncommon in the dialysis population and is associated with positive aftereffects. Nephrology care providers should be aware of the occurrence and aftereffects of NDEs. The high occurrence of life-threatening events, availability of medical records, and accessibility and cooperativeness of patients make the dialysis population very suitable for NDE research.


Asunto(s)
Actitud Frente a la Muerte , Muerte , Diálisis Renal/psicología , Estudios Transversales , Femenino , Humanos , Fallo Renal Crónico/terapia , Acontecimientos que Cambian la Vida , Persona de Mediana Edad , Religión , Encuestas y Cuestionarios , Uremia
7.
Artículo en Zh | WPRIM | ID: wpr-666497

RESUMEN

OBJECTIVE To investigate how MLKL functions on the membrane and explore its electrophysiological characters and structure. METHODS The full-length human MLKL were expressed in SF21 cells and purified using glutathione-sepharose affinity chromatography. The currents of purified MLKL proteins were recorded in avoltage-clamp mode using a Warner BC-535 bilayer clamp amplifier. The currents were digitized using pCLAMP 10.2 software. HEK293 cells were cultured and transfected with MLKL plasmid. Cell viability was examined using the CellTiter- Glo Luminescent Cell Viability Assay kit. RESULT MLKL forms cation channels that are permeable preferentially to Mg2+ rather than Ca2+ in the presence of Na+ and K+. Moreover,each MLKL monomer contains five transmembrane helices:H1, H2, H3 , H5 and H6 of the N-terminal domain which is sufficient to form channels. Finally, MLKL-induced membrane depolarization and cell death exhibit a positive correlation to its channel activity.

8.
Nephrology (Carlton) ; 11(2): 147-50, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16669978

RESUMEN

Colchicine myoneuropathy is a rare and often underdiagnosed disease. It often presents as painless subacute muscle weakness. We present a case of painful colchicine myoneuropathy in a 76-year-old man with chronic renal failure and gout. Published work about clinical presentations of colchicine myoneuropathy in gouty arthritis patients are reviewed. During the previous year, the patient had a drug regimen of colchicine 0.5 mg three times per day for a 3 day course each month. He developed bilateral lower leg weakness and severe myalgia. His serum creatinine level was 680.7 micromol/L and creatinine kinase was 959 IU/L on admission. Laboratory findings included decreasing amplitude of motor and sensory nerve conduction velocity and an electromyogram showed small amplitude, short duration polyphasic waves over the right biceps. A muscle biopsy disclosed vacuolar changes in the cytoplasm. These results all supported a diagnosis of colchicine myoneuropathy. After cessation of colchicine, the creatinine kinase level decreased approximately 50% in 6 days, myalgia subsided and his muscle weakness improved gradually over the next 2 weeks.


Asunto(s)
Colchicina/efectos adversos , Supresores de la Gota/efectos adversos , Gota/tratamiento farmacológico , Fallo Renal Crónico/complicaciones , Enfermedades Neuromusculares/diagnóstico , Anciano de 80 o más Años , Gota/complicaciones , Humanos , Masculino , Enfermedades Neuromusculares/inducido químicamente
9.
Kidney Int ; 68(2): 760-5, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16014053

RESUMEN

BACKGROUND: Sexual function is one aspect of physical functioning. Sexual dysfunction, no matter the etiology, could cause distress. In female hemodialysis patients, sexual problems have often been neglected in clinical performance and research. METHODS: We conducted this study by use of self-reported questionnaires. A total of 578 female hemodialysis patients in northern Taiwan were included in this study. Demographic data, comorbid diseases, medications in use, biochemical, and hematologic parameters were analyzed. All patients were asked to complete by themselves three questionnaires: (1) the Index of Female Sexual Function (IFSF) to assess sexual function; (2) the Beck Depression Inventory (BDI) (Chinese version) to rate the severity of depressive symptoms; and (3) the 36-item Short Form Health Survey Questionnaire (SF-36, Taiwan Standard Version 1.0) to survey their quality of life. RESULTS: A total of 138 female patients were enrolled into further analysis. The mean age was 48.7 +/- 11.2 years old. The mean IFSF score was 24.5 +/- 9.3. Age, BDI score, and serum triglyceride levels were the independent factors of dysfunction in each sexual functional dimension. Patients with higher IFSF scores had significantly higher scores in physical functioning and mental health (P= 0.007 and 0.018, respectively). Patients with higher intercourse satisfaction had significantly higher general health scores (P= 0.001). CONCLUSION: Sexual dysfunction is frequent in the female hemodialysis population. It is strongly associated with increasing age, dyslipidemia, and depression. The subjects with sexual dysfunction had poorer quality of life. The diagnosis and treatment of sexual dysfunction should be included in the clinical assessment.


Asunto(s)
Fallo Renal Crónico/epidemiología , Diálisis Renal/estadística & datos numéricos , Disfunciones Sexuales Fisiológicas/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Depresión/epidemiología , Femenino , Humanos , Fallo Renal Crónico/psicología , Fallo Renal Crónico/terapia , Modelos Lineales , Persona de Mediana Edad , Prevalencia , Calidad de Vida , Disfunciones Sexuales Fisiológicas/psicología , Encuestas y Cuestionarios
10.
J Nutr Biochem ; 13(11): 653-663, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12550062

RESUMEN

This study investigated the supplementation with vitamin C or/and E on the antioxidant system in hemodialysis patients. Thirty-eight hemodialysis patients (27 males and 11 females) with the average of 60 years old were divided into four groups: placebo (400 mg starch/time), vitamin C (400 mg/time)-, vitamin E (400 mg d,l- alpha-tocopheryl acetate/time)-, and vitamin C (400 mg/time) + E (400 mg d,l- alpha-tocopheryl acetate/time)-supplemented groups for 6-week supplementation. The patients orally received three capsules of placebo or antioxidant(s) three times a week after finishing hemodialysis. Thirty-six healthy subjects (22 males and 14 females) with the average of 58 years old were recruited as the control group. Hemodialysis patients significantly decreased plasma vitamin C by 32%, erythrocyte glutathione by 26%, and plasma total antioxidant status by 9%, but increased plasma lipid peroxide levels by 102% compared with the control group at the baseline. The levels of plasma vitamin C and total antioxidant status significantly decreased by 24% and 18%, respectively, from the post-dialysate compared with those from the pre-dialysate. At week 6, vitamin C + E-supplemented group significantly increased plasma vitamin C and E, erythrocyte glutathione, and plasma antioxidant status, and inhibited plasma lipid peroxides compared with placebo group. Additionally, vitamin C + E-supplemented group had higher plasma vitamin C, vitamin E, and total antioxidant status, and lower plasma lipid peroxides than placebo group even at least 2 weeks after the termination of the supplements. Therefore, antioxidant vitamin supplements could improve antioxidant status and decrease lipid peroxides of hemodialysis patients.

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