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1. Ultrahigh energy storage in multilayer BiFeO3–BaTiO3–NaTaO3 relaxor ferroelectric ceramics.

Author

Montecillo, Rhys, Chien, R. R., Chen, Cheng-Sao, Wu, Po-Hsien, Tu, Chi-Shun, and Feng, Kuei-Chih

Abstract

The rising challenge of high-density electric energy storage has accelerated the research of electric energy-storage capacitors due to their high power density and voltage resistance, excellent temperature stability, and environmental friendliness. However, lead-free ferroelectric capacitors generally have a low discharge energy density. This study used a multilayer ceramic capacitor (MLCC) design with active ceramic layers of relaxor ferroelectric NaTaO3-modified BiFeO3–BaTiO3 co-sintered with 90Ag/10Pd interlayer electrodes. Superb recoverable energy densities of Wrec ∼2.8 J cm−3 with an energy efficiency of η ∼73% at 400 kV cm−1 and Wrec ∼4.5 J cm−3 with an energy efficiency of η ∼77% at 450 kV cm−1 were attained, respectively, in 9-active-ceramic-layer and 24-active-ceramic-layer MLCCs. Excellent thermal stability and fatigue resistance of energy storage capability were achieved up to 180 °C and exceeding 1 × 104 cycles. The ultrahigh energy-storage properties can be linked to the synergistic effects of multiple local lattice distortions, nanoscale structures, and interfacial E fields at grain boundaries. This report demonstrates an efficient scheme to utilize ternary BiFeO3–BaTiO3-based ceramics via the MLCC technology for ultrahigh-energy-density electrostatic energy storage. [ABSTRACT FROM AUTHOR]

Published
2024
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2. Achieving high microscale photoconductivity in Gd-modified bismuth ferrite via modulating ferroelectric polarization.

Author

Mana-ay, Haidee, Chen, Cheng-Sao, Chien, R. R., Tu, Chi-Shun, and Chen, Pin-Yi

Abstract

This work demonstrates the critical role of ferroelectric polarization in determining the two-dimensional photoconduction properties of 7 mol% Gd-modified bismuth ferrite (BiFeO3, BFO) ceramics under 405 nm-wavelength illumination. A significant enhancement in photocurrent upon external electric field poling is correlated with adjustment in the internal electric field induced by ferroelectric polarization, which boosts the charge mobility via tilting the energy-band structure. The enhanced photoconduction is linked to the domain reorientation and increased domain walls. The evolution plays a critical role in the electric field-enhanced photocurrent since domain walls serve as conductive transport networks for charge flow. Furthermore, a sequential increase in photocurrent with increasing illumination intensity can be attributed to an increased number of photo-generated charge carriers. This study uncovers the vital effects of ferroelectric polarization on the photoelectric properties of BFO-based materials, thus providing essential insight for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Published
2024
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3. Novel small molecules disrupting Hec1/Nek2 interaction ablate tumor progression by triggering Nek2 degradation through a death-trap mechanism

Author

Hu, C-M, Zhu, J, Guo, XE, Chen, W, Qiu, X-L, Ngo, B, Chien, R, Wang, YV, Tsai, CY, Wu, G, Kim, Y, Lopez, R, Chamberlin, AR, Lee, EY-HP, and Lee, W-H

Subjects
Cancer, Breast Cancer, Development of treatments and therapeutic interventions, 5.1 Pharmaceuticals, Animals, Benzamides, Binding Sites, Cell Line, Tumor, Cytoskeletal Proteins, Disease Models, Animal, Disease Progression, Gene Expression, Heterografts, Humans, Indoles, Inhibitory Concentration 50, Mitosis, Models, Molecular, Molecular Conformation, NIMA-Related Kinases, Neoplasms, Nuclear Proteins, Phosphorylation, Prognosis, Protein Binding, Protein Serine-Threonine Kinases, Proteolysis, Thiazoles, Valerates, Protein-Serine-Threonine Kinases, Clinical Sciences, Oncology and Carcinogenesis, Oncology & Carcinogenesis
Abstract

Hec1 (highly expressed in cancer 1) or Nek2 (NIMA-related kinase 2) is often overexpressed in cancers with poor prognosis. Both are critical mitotic regulators, and phosphorylation of Hec1 S165 by Nek2 is required for proper chromosome segregation. Therefore, inactivation of Hec1 and Nek2 by targeting their interaction with small molecules represents an ideal strategy for tackling these types of cancers. Here we showed that new derivatives of INH (inhibitor for Nek2 and Hec1 binding) bind to Hec1 at amino acids 394-408 on W395, L399 and K400 residues, effectively blocking Hec1 phosphorylation on S165 by Nek2, and killing cancer cells at the nanomolar range. Mechanistically, the D-box (destruction-box) region of Nek2 specifically binds to Hec1 at amino acids 408-422, immediately adjacent to the INH binding motif. Subsequent binding of Nek2 to INH-bound Hec1 triggered proteasome-mediated Nek2 degradation, whereas the Hec1 binding defective Nek2 mutant, Nek2 R361L, resisted INH-induced Nek2 degradation. This finding unveils a novel drug-action mechanism where the binding of INHs to Hec1 forms a virtual death-trap to trigger Nek2 degradation and eventually cell death. Furthermore, analysis of the gene expression profiles of breast cancer patient samples revealed that co-elevated expressions of Hec1 and Nek2 correlated with the shortest survival. Treatment of mice with this kind of tumor with INHs significantly suppressed tumor growth without obvious toxicity. Taken together, the new INH derivatives are suitable for translation into clinical application.

Published
2015

4. Configuration-entropy effects on BiFeO3–BaTiO3 relaxor ferroelectric ceramics for high-density energy storage.

Author

Montecillo, Rhys, Chen, Cheng-Sao, Feng, Kuei-Chih, Chien, R. R., Chen, Pin-Yi, and Tu, Chi-Shun

Abstract

High energy-storage capability and electric breakdown strength are critical elements in next-generation pulse-power dielectric capacitors. In this report, perovskite (Bi0.7Ba0.3)1−xNax(Fe0.7Ti0.3)1−xTaxO3 relaxor ferroelectric ceramics (x = 0–0.3) were tailored in terms of configuration entropy from a medium entropy of 1.21R to a high entropy of 2.07R to improve energy storage. The integration of paraelectric NaTaO3 into BiFeO3–BaTiO3 results in breaking of the long-range order and formation of multiple lattice distortions toward relaxor ferroelectric characteristics. Excellent recoverable energy densities of 9.6 J cm−3 and 10.3 J cm−3 with efficiencies of 77% and 68% at 350 kV cm−1 and 550 kV cm−1 (at 10 Hz) were achieved for x = 0.15 and 0.20, respectively. Wide operating frequency (1–100 Hz) and temperature (25 °C–150 °C) stabilities were confirmed at 300 kV cm−1. Grain boundaries and nanoclusters play critical roles as electric barriers to suppress charge mobility and increase electric breakdown strength. This study presents a promising scheme to utilize high-configuration entropy BiFeO3–BaTiO3-based ceramics for high energy-density electrostatic capacitors. [ABSTRACT FROM AUTHOR]

Published
2024
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6. Strategies to manage hepatitis C virus infection disease burden—Volume 4

Author

Chen, D. S., Hamoudi, W., Mustapha, B., Layden, J., Nersesov, A., Reic, T., Garcia, V., Rios, C., Mateva, L., Njoya, O., Al‐Busafi, S. A., Abdelmageed, M. K., Abdulla, M., Adda, D., Akin, O., Al Baqali, A., Al Dweik, N., Al Ejji, K., Al ghazzawi, I., Al Kaabi, S., Al Naamani, K., Al Qamish, J., Al Sadadi, M., Al Salman, J., AlBadri, M., Al‐Romaihi, H. E., Ampofo, W., Antonov, K., Anyaike, C., Arome, F., Bane, A., Blach, S., Borodo, M. M., Brandon, S. M., Bright, B., Butt, M. T., Cardenas, I., Chan, H. L. Y., Chen, C. J., Chen, P. J., Chien, R. N., Chuang, W. L., Cuellar, D., Derbala, M., Elbardiny, A. A., Estes, C., Farag, E., Fung, J., Gamkrelidze, I., Genov, J., Ghandour, Z., Ghuloom, M., Gomez, B., Gunter, J., Habeeb, J., Hajelssedig, O., Himatt, S. M., Hrstic, I., Hu, C. C., Huang, C. F., Hui, Y. T., Jahis, R., Jelev, D., John, A. K., Kaliaskarova, K. S., Kamel, Y., Kao, J. H., Khamis, J., Khattabi, H., Khoudri, I., Konysbekova, A., Kotzev, I., Lai, M. S., Lao, W. C., Lee, M. H., Lesi, O., Li, M., Lo, A., Loo, C. K., Lukšić, B., Maaroufi, A., Malu, A. O., Mitova, R., Mohamed, R., Morović, M., Murphy, K., Nde, H., Ngige, E., Njouom, R., Nonković, D., Obekpa, S., Oguche, S., Okolo, E. E., Omede, O., Omuemu, C., Ondoa, P., Opare‐Sem, O., Owusu‐Ofori, S., Phillips, R. O., Prokopenko, Y. N., Razavi, H., Razavi‐Shearer, D., Razavi‐Shearer, K., Redae, B., Rinke de Wit, T., Robbins, S., Roberts, L. R., Sanad, S. J., Sharma, M., Simonova, M., Su, T. H., Sultan, K., Tan, S. S., Tchernev, K., Tsang, O. T. Y., Tsang, S., Tzeuton, C., Ugoeze, S., Uzochukwu, B., Vi, R., Vince, A., Wani, H. U., Wong, V. W. S., Workneh, A., Yacoub, R., Yesmembetov, K. I., Youbi, M., Yuen, M. F., and Schmelzer, J. D.

Published
2017
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7. The present and future disease burden of hepatitis C virus infections with todayʼs treatment paradigm: Volume 4

Author

Chan, H. L. Y., Chen, C. J., Omede, O., Al Qamish, J., Al Naamani, K., Bane, A., Tan, S. S., Simonova, M., Cardenas, I., Derbala, M., Akin, O., Phillips, R. O., Abdelmageed, M. K., Abdulla, M., Adda, D., Al Baqali, A., Al Dweik, N., Al Ejji, K., Al ghazzawi, I., Al Kaabi, S., Al Sadadi, M., Al Salman, J., AlBadri, M., Al‐Busafi, S. A., Al‐Romaihi, H. E., Ampofo, W., Antonov, K., Anyaike, C., Arome, F., Blach, S., Borodo, M. M., Brandon, S. M., Bright, B., Butt, M. T., Chen, D. S., Chen, P. J., Chien, R. N., Chuang, W. L., Cuellar, D., Elbardiny, A. A., Estes, C., Farag, E., Fung, J., Gamkrelidze, I., Garcia, V., Genov, J., Ghandour, Z., Ghuloom, M., Gomez, B., Gunter, J., Habeeb, J., Hajelssedig, O., Hamoudi, W., Himatt, S. M., Hrstic, I., Hu, C. C., Huang, C. F., Hui, Y. T., Jahis, R., Jelev, D., John, A. K., Kaliaskarova, K. S., Kamel, Y., Kao, J. H., Khamis, J., Khattabi, H., Khoudri, I., Konysbekova, A., Kotzev, I., Lai, M. S., Lao, W. C., Layden, J., Lee, M. H., Lesi, O., Li, M., Lo, A., Loo, C. K., Lukšić, B., Maaroufi, A., Malu, A. O., Mateva, L., Mitova, R., Mohamed, R., Morović, M., Murphy, K., Mustapha, B., Nersesov, A., Ngige, E., Njouom, R., Njoya, O., Nonković, D., Obekpa, S., Oguche, S., Okolo, E. E., Omuemu, C., Ondoa, P., Opare‐Sem, O., Owusu‐Ofori, S., Prokopenko, Y. N., Razavi, H., Razavi‐Shearer, D., Razavi‐Shearer, K., Redae, B., Reic, T., Rinke de Wit, T., Rios, C., Robbins, S., Roberts, L. R., Sanad, S. J., Schmelzer, J. D., Sharma, M., Su, T. H., Sultan, K., Tchernev, K., Tsang, O. T. Y., Tsang, S., Tzeuton, C., Ugoeze, S., Uzochukwu, B., Vi, R., Vince, A., Wani, H. U., Wong, V. W. S., Workneh, A., Yacoub, R., Yesmembetov, K. I., Youbi, M., Yuen, M. F., and Nde, H.

Published
2017
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8. Historical epidemiology of hepatitis C virus in select countries—volume 4

Author

Maaroufi, A., Vince, A., Himatt, S. M., Mohamed, R., Fung, J., Opare‐Sem, O., Workneh, A., Njouom, R., Al ghazzawi, I., Abdulla, M., Kaliaskarova, K. S., Owusu‐Ofori, S., Abdelmageed, M. K., Adda, D., Akin, O., Al Baqali, A., Al Dweik, N., Al Ejji, K., Al Kaabi, S., Al Naamani, K., Al Qamish, J., Al Sadadi, M., Al Salman, J., AlBadri, M., Al‐Busafi, S. A., Al‐Romaihi, H. E., Ampofo, W., Antonov, K., Anyaike, C., Arome, F., Bane, A., Blach, S., Borodo, M. M., Brandon, S. M., Bright, B., Butt, M. T., Cardenas, I., Chan, H. L. Y., Chen, C. J., Chen, D. S., Chen, P. J., Chien, R. N., Chuang, W. L., Cuellar, D., Derbala, M., Elbardiny, A. A., Estes, C., Farag, E., Gamkrelidze, I., Garcia, V., Genov, J., Ghandour, Z., Ghuloom, M., Gomez, B., Gunter, J., Habeeb, J., Hajelssedig, O., Hamoudi, W., Hrstic, I., Hu, C. C., Huang, C. F., Hui, Y. T., Jahis, R., Jelev, D., John, A. K., Kamel, Y., Kao, J. H., Khamis, J., Khattabi, H., Khoudri, I., Konysbekova, A., Kotzev, I., Lai, M. S., Lao, W. C., Layden, J., Lee, M. H., Lesi, O., Li, M., Lo, A., Loo, C. K., Lukšić, B., Malu, A. O., Mateva, L., Mitova, R., Morović, M., Murphy, K., Mustapha, B., Nde, H., Nersesov, A., Ngige, E., Njoya, O., Nonković, D., Obekpa, S., Oguche, S., Okolo, E. E., Omede, O., Omuemu, C., Ondoa, P., Phillips, R. O., Prokopenko, Y. N., Razavi, H., Razavi‐Shearer, D., Redae, B., Reic, T., Rinke de Wit, T., Rios, C., Robbins, S., Roberts, L. R., Sanad, S. J., Schmelzer, J. D., Sharma, M., Simonova, M., Su, T. H., Sultan, K., Tan, S. S., Tchernev, K., Tsang, O. T. Y., Tsang, S., Tzeuton, C., Ugoeze, S., Uzochukwu, B., Vi, R., Wani, H. U., Wong, V. W. S., Yacoub, R., Yesmembetov, K. I., Youbi, M., Yuen, M. F., and Razavi‐Shearer, K.

Published
2017
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9. Asian-Pacific clinical practice guidelines on the management of hepatitis B: a 2015 update

Author

Sarin, S. K., Kumar, M., Lau, G. K., Abbas, Z., Chan, H. L. Y., Chen, C. J., Chen, D. S., Chen, H. L., Chen, P. J., Chien, R. N., Dokmeci, A. K., Gane, Ed, Hou, J. L., Jafri, W., Jia, J., Kim, J. H., Lai, C. L., Lee, H. C., Lim, S. G., Liu, C. J., Locarnini, S., Al Mahtab, M., Mohamed, R., Omata, M., Park, J., Piratvisuth, T., Sharma, B. C., Sollano, J., Wang, F. S., Wei, L., Yuen, M. F., Zheng, S. S., and Kao, J. H.

Published
2016
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10. Off-Therapy Response After Nucleos(t)ide Analogue Withdrawal in Patients With Chronic Hepatitis B:An International, Multicenter, Multiethnic Cohort (RETRACT-B Study)

Author

Hirode, G., Choi, H. S. J., Chen, C. H., Su, T. H., Seto, W. K., Van Hees, S., Papatheodoridi, M., Lens, S., Wong, G., Brakenhoff, S. M., Chien, R. N., Feld, J., Sonneveld, M. J., Chan, H. L. Y., Forns, X., Papatheodoridis, G. V., Vanwolleghem, T., Yuen, M. F., Hsu, Y. C., Kao, J. H., Cornberg, M., Hansen, B. E., Jeng, W. J., Janssen, H. L. A., Hirode, G., Choi, H. S. J., Chen, C. H., Su, T. H., Seto, W. K., Van Hees, S., Papatheodoridi, M., Lens, S., Wong, G., Brakenhoff, S. M., Chien, R. N., Feld, J., Sonneveld, M. J., Chan, H. L. Y., Forns, X., Papatheodoridis, G. V., Vanwolleghem, T., Yuen, M. F., Hsu, Y. C., Kao, J. H., Cornberg, M., Hansen, B. E., Jeng, W. J., and Janssen, H. L. A.

Abstract

Background & Aims: Functional cure, defined based on hepatitis B surface antigen (HBsAg) loss, is rare during nucleos(t)ide analogue (NA) therapy and guidelines on finite NA therapy have not been well established. We aim to analyze off-therapy outcomes after NA cessation in a large, international, multicenter, multiethnic cohort of patients with chronic hepatitis B (CHB). Methods: This cohort study included patients with virally suppressed CHB who were hepatitis B e antigen (HBeAg)–negative and stopped NA therapy. Primary outcome was HBsAg loss after NA cessation, and secondary outcomes included virologic, biochemical, and clinical relapse, alanine aminotransferase flare, retreatment, and liver-related events after NA cessation. Results: Among 1552 patients with CHB, cumulative probability of HBsAg loss was 3.2% at 12 months and 13.0% at 48 months of follow-up. HBsAg loss was higher among Whites (vs Asians: subdistribution hazard ratio, 6.8; 95% confidence interval, 2.7–16.8; P < .001) and among patients with HBsAg levels <100 IU/mL at end of therapy (vs ≥100 IU/mL: subdistribution hazard ratio, 22.5; 95% confidence interval, 13.1–38.7; P < .001). At 48 months of follow-up, Whites with HBsAg levels <1000 IU/mL and Asians with HBsAg levels <100 IU/mL at end of therapy had a high predicted probability of HBsAg loss (>30%). Incidence rate of hepatic decompensation and hepatocellular carcinoma was 0.48 per 1000 person-years and 0.29 per 1000 person-years, respectively. Death occurred in 7/19 decompensated patients and 2/14 patients with hepatocellular carcinoma. Conclusions: The best candidates for NA withdrawal are virally suppressed, HBeAg- negative, noncirrhotic patients with CHB with low HBsAg levels, particularly Whites with <1000 IU/mL and Asians with <100 IU/mL. However, strict surveillance is recommended to prevent deterioration.

Published
2022

11. Clean air policies are key for successfully mitigating Arctic warming

Author

von Salzen, K., Whaley, C.H., Anenberg, S.C., Van Dingenen, R., Klimont, Z., Flanner, M.G., Mahmood, R., Arnold, S.R., Beagley, S., Chien, R.-Y., Christensen, J.H., Eckhardt, S., Ekman, A.M.L., Evangeliou, N., Faluvegi, G., Fu, J.S., Gauss, M., Gong, W., Hjorth, J.L., Im, U., Krishnan, S., Kupiainen, K., Kühn, T., Langner, J., Law, K.S., Marelle, L., Olivié, D., Onishi, T., Oshima, N., Paunu, V.-V., Peng, Y., Plummer, D., Pozzoli, L., Rao, S., Raut, J.-C., Sand, M., Schmale, J., Sigmond, M., Thomas, M.A., Tsigaridis, K., Tsyro, S., Turnock, S.T., Wang, M., Winter, B., von Salzen, K., Whaley, C.H., Anenberg, S.C., Van Dingenen, R., Klimont, Z., Flanner, M.G., Mahmood, R., Arnold, S.R., Beagley, S., Chien, R.-Y., Christensen, J.H., Eckhardt, S., Ekman, A.M.L., Evangeliou, N., Faluvegi, G., Fu, J.S., Gauss, M., Gong, W., Hjorth, J.L., Im, U., Krishnan, S., Kupiainen, K., Kühn, T., Langner, J., Law, K.S., Marelle, L., Olivié, D., Onishi, T., Oshima, N., Paunu, V.-V., Peng, Y., Plummer, D., Pozzoli, L., Rao, S., Raut, J.-C., Sand, M., Schmale, J., Sigmond, M., Thomas, M.A., Tsigaridis, K., Tsyro, S., Turnock, S.T., Wang, M., and Winter, B.

Abstract

A tighter integration of modeling frameworks for climate and air quality is urgently needed to assess the impacts of clean air policies on future Arctic and global climate. We combined a new model emulator and comprehensive emissions scenarios for air pollutants and greenhouse gases to assess climate and human health co-benefits of emissions reductions. Fossil fuel use is projected to rapidly decline in an increasingly sustainable world, resulting in far-reaching air quality benefits. Despite human health benefits, reductions in sulfur emissions in a more sustainable world could enhance Arctic warming by 0.8 °C in 2050 relative to the 1995–2014, thereby offsetting climate benefits of greenhouse gas reductions. Targeted and technically feasible emissions reduction opportunities exist for achieving simultaneous climate and human health co-benefits. It would be particularly beneficial to unlock a newly identified mitigation potential for carbon particulate matter, yielding Arctic climate benefits equivalent to those from carbon dioxide reductions by 2050.

Published
2022
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12. Off-Therapy Response After Nucleos(t)ide Analogue Withdrawal in Patients With Chronic Hepatitis B: An International, Multicenter, Multiethnic Cohort (RETRACT-B Study)

Author

Hirode, G. Choi, H.S.J. Chen, C.-H. Su, T.-H. Seto, W.-K. Van Hees, S. Papatheodoridi, M. Lens, S. Wong, G. Brakenhoff, S.M. Chien, R.-N. Feld, J. Sonneveld, M.J. Chan, H.L.Y. Forns, X. Papatheodoridis, G.V. Vanwolleghem, T. Yuen, M.-F. Hsu, Y.-C. Kao, J.-H. Cornberg, M. Hansen, B.E. Jeng, W.-J. Janssen, H.L.A. RETRACT-B Study Group

Abstract

Background & Aims: Functional cure, defined based on hepatitis B surface antigen (HBsAg) loss, is rare during nucleos(t)ide analogue (NA) therapy and guidelines on finite NA therapy have not been well established. We aim to analyze off-therapy outcomes after NA cessation in a large, international, multicenter, multiethnic cohort of patients with chronic hepatitis B (CHB). Methods: This cohort study included patients with virally suppressed CHB who were hepatitis B e antigen (HBeAg)–negative and stopped NA therapy. Primary outcome was HBsAg loss after NA cessation, and secondary outcomes included virologic, biochemical, and clinical relapse, alanine aminotransferase flare, retreatment, and liver-related events after NA cessation. Results: Among 1552 patients with CHB, cumulative probability of HBsAg loss was 3.2% at 12 months and 13.0% at 48 months of follow-up. HBsAg loss was higher among Whites (vs Asians: subdistribution hazard ratio, 6.8; 95% confidence interval, 2.7–16.8; P < .001) and among patients with HBsAg levels 30%). Incidence rate of hepatic decompensation and hepatocellular carcinoma was 0.48 per 1000 person-years and 0.29 per 1000 person-years, respectively. Death occurred in 7/19 decompensated patients and 2/14 patients with hepatocellular carcinoma. Conclusions: The best candidates for NA withdrawal are virally suppressed, HBeAg- negative, noncirrhotic patients with CHB with low HBsAg levels, particularly Whites with

Published
2022

20. Intense agricultural irrigation induced contrasting precipitation changes in Saudi Arabia

Author

Lo, M.-H., Wey, H.-W., Im, E.-S., Tang, L.I., Anderson, R.G., Wu, R.-J., Chien, R.-Y., Wei, J., AghaKouchak, A., Wada, Y., Lo, M.-H., Wey, H.-W., Im, E.-S., Tang, L.I., Anderson, R.G., Wu, R.-J., Chien, R.-Y., Wei, J., AghaKouchak, A., and Wada, Y.

Abstract

Groundwater extraction has grown tremendously in Saudi Arabia to meet the irrigation water demand since the 1980s, and irrigation is one of the major anthropogenic factors modulating regional hydroclimate. However, the link between irrigation and hydroclimate is not well understood in a dry region such as Saudi Arabia. In this study, we utilize three different regional climate models to explore the physical mechanisms behind the irrigation impacts in this region. The results are robust across models and show that when irrigation is applied, wetter soil results in higher evapotranspiration and cools the lower atmosphere, leading to an anomalous pressure field and alters vapor transportation. Precipitation decreases locally because of the local cooling effect, whereas additional water vapor convergence enhances precipitation west to the irrigated region. This west–east contrast of precipitation change indicates a possible link between irrigation expansion in the 1980s and subsequent decadal precipitation variations in central Saudi Arabia. We further find from observations a decadal west–east contrast of precipitation changes in Saudi Arabia to support the similar finding in the models. This study implies the importance of including anthropogenic water management in climate models and provides a better understanding of how irrigation impacts local-to-regional climate.

Published
2021

26. Hepatitis B Surface Antigen Levels Can Be Used to Rule Out Cirrhosis in Hepatitis B e Antigen-Positive Chronic Hepatitis B: Results From the SONIC-B Study.

Author

Sonneveld, Milan J, Hansen, Bettina E, Brouwer, Willem P, Chan, Henry L-Y, Piratvisuth, Teerha, Jia, Ji-Dong, Zeuzem, Stefan, Chien, Rong-Nan, Knegt, Robert J de, Wat, Cynthia, Pavlovic, Vedran, Gaggar, Anuj, Xie, Qing, Buti, Maria, Man, Robert A de, Janssen, Harry L A, Group, SONIC-B Study, Chien, R N, de Knegt, R J, and de Man, R A

Abstract

Background: Serum hepatitis B surface antigen (HBsAg) levels correlate with the duration of chronic hepatitis B virus (HBV) infection and may predict the extent of hepatic fibrosis.Methods: We analyzed data from the SONIC-B database, which contains data from 8 global randomized trials and 2 large hepatology centers. Relationship between HBsAg levels and presence of significant fibrosis (Ishak 3-4) or cirrhosis (Ishak 5-6) were explored, and clinically relevant cutoffs were identified to rule out cirrhosis.Results: The dataset included 2779 patients: 1866 hepatitis B e antigen (HBeAg)-positive; 322 with cirrhosis. Among HBeAg-positive patients, lower HBsAg levels were associated with higher rates of significant fibrosis (odds ratio [OR], 0.419; P < .001) and cirrhosis (OR, 0.435; P < .001). No relationship was observed among HBeAg-negative patients. Among HBeAg-positive patients, genotype-specific HBsAg cutoffs had excellent negative predictive values (>97%) and low misclassification rates (≤7.1%) and may therefore have utility in ruling out cirrhosis. Diagnostic performance of the HBsAg cutoffs was comparable among patients in whom cirrhosis could not be ruled out with fibrosis 4 (FIB-4).Conclusions: Hepatitis B virus genotype-specific HBsAg cutoffs may have utility in ruling out presence of cirrhosis in HBeAg-positive patients with genotypes B, C, and D and can be an adjunct to FIB-4 to reduce the need for further testing. [ABSTRACT FROM AUTHOR]

Published
2022
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48. Global prevalence, treatment, and prevention of hepatitis B virus infection in 2016: a modelling study

Author

Razavi-Shearer, D. Gamkrelidze, I. Nguyen, M.H. Chen, D.-S. Van Damme, P. Abbas, Z. Abdulla, M. Abou Rached, A. Adda, D. Aho, I. Akarca, U. Al Ali, F.H. Lawati, F.A.L. Naamani, K.A.L. Alashgar, H.I. Alavian, S.M. Alawadhi, S. Albillos, A. Al-Busafi, S.A. Aleman, S. Alfaleh, F.Z. Aljumah, A.A. Anand, A.C. Anh, N.T. Arends, J.E. Arkkila, P. Athanasakis, K. Bane, A. Ben-Ari, Z. Berg, T. Bizri, A.R. Blach, S. Brandão Mello, C.E. Brandon, S.M. Bright, B. Bruggmann, P. Brunetto, M. Buti, M. Chan, H.L.Y. Chaudhry, A. Chien, R.-N. Choi, M.S. Christensen, P.B. Chuang, W.-L. Chulanov, V. Clausen, M.R. Colombo, M. Cornberg, M. Cowie, B. Craxi, A. Croes, E.A. Cuellar, D.A. Cunningham, C. Desalegn, H. Drazilova, S. Duberg, A.-S. Egeonu, S.S. El-Sayed, M.H. Estes, C. Falconer, K. Ferraz, M.L.G. Ferreira, P.R. Flisiak, R. Frankova, S. Gaeta, G.B. García-Samaniego, J. Genov, J. Gerstoft, J. Goldis, A. Gountas, I. Gray, R. Guimarães Pessôa, M. Hajarizadeh, B. Hatzakis, A. Hézode, C. Himatt, S.M. Hoepelman, A. Hrstic, I. Hui, Y.-T.T. Husa, P. Jahis, R. Janjua, N.Z. Jarcuška, P. Jaroszewicz, J. Kaymakoglu, S. Kershenobich, D. Kondili, L.A. Konysbekova, A. Krajden, M. Kristian, P. Laleman, W. Lao, W.-C.C. Layden, J. Lazarus, J.V. Lee, M.-H. Liakina, V. Lim, Y.-S.S. Loo, C.-K.K. Lukšic, B. Malekzadeh, R. Malu, A.O. Mamatkulov, A. Manns, M. Marinho, R.T. Maticic, M. Mauss, S. Memon, M.S. Mendes Correa, M.C. Mendez-Sanchez, N. Merat, S. Metwally, A.M. Mohamed, R. Mokhbat, J.E. Moreno, C. Mossong, J. Mourad, F.H. Müllhaupt, B. Murphy, K. Musabaev, E. Nawaz, A. Nde, H.M. Negro, F. Nersesov, A. Nguyen, V.T.T. Njouom, R. Ntagirabiri, R. Nurmatov, Z. Obekpa, S. Ocama, P. Oguche, S. Omede, O. Omuemu, C. Opare-Sem, O. Opio, C.K. Örmeci, N. Papatheodoridis, G. Pasini, K. Pimenov, N. Poustchi, H. Quang, T.D. Qureshi, H. Ramji, A. Razavi-Shearer, K. Redae, B. Reesink, H.W. Rios, C.Y. Rjaskova, G. Robbins, S. Roberts, L.R. Roberts, S.K. Ryder, S.D. Safadi, R. Sagalova, O. Salupere, R. Sanai, F.M. Sanchez-Avila, J.F. Saraswat, V. Sarrazin, C. Schmelzer, J.D. Schréter, I. Scott, J. Seguin-Devaux, C. Shah, S.R. Sharara, A.I. Sharma, M. Shiha, G.E. Shin, T. Sievert, W. Sperl, J. Stärkel, P. Stedman, C. Sypsa, V. Tacke, F. Tan, S.S. Tanaka, J. Tomasiewicz, K. Urbanek, P. van der Meer, A.J. Van Vlierberghe, H. Vella, S. Vince, A. Waheed, Y. Waked, I. Walsh, N. Weis, N. Wong, V.W. Woodring, J. Yaghi, C. Yang, H.-I. Yang, C.-L. Yesmembetov, K. Yosry, A. Yuen, M.-F. Yusuf, M.A.M. Zeuzem, S. Razavi, H. The Polaris Observatory Collaborators

Abstract

Background: The 69th World Health Assembly approved the Global Health Sector Strategy to eliminate viral hepatitis by 2030. Although no virological cure exists for hepatitis B virus (HBV) infection, existing therapies to control viral replication and prophylaxis to minimise mother-to-child transmission make elimination of HBV feasible. We aimed to estimate the national, regional, and global prevalence of HBsAg in the general population and in the population aged 5 years in 2016, as well as coverage of prophylaxis, diagnosis, and treatment. Methods: In this modelling study, we used a Delphi process that included a literature review in PubMed and Embase, followed by interviews with experts, to quantify the historical epidemiology of HBV infection. We then used a dynamic HBV transmission and progression model to estimate the country-level and regional-level prevalence of HBsAg in 2016 and the effect of prophylaxis and treatment on disease burden. Findings: We developed models for 120 countries, 78 of which were populated with data approved by experts. Using these models, we estimated that the global prevalence of HBsAg in 2016 was 3·9% (95% uncertainty interval [UI] 3·4–4·6), corresponding to 291 992 000 (251 513 000–341 114 000) infections. Of these infections, around 29 million (10%) were diagnosed, and only 4·8 million (5%) of 94 million individuals eligible for treatment actually received antiviral therapy. Around 1·8 (1·6–2·2) million infections were in children aged 5 years, with a prevalence of 1·4% (1·2–1·6). We estimated that 87% of infants had received the three-dose HBV vaccination in the first year of life, 46% had received timely birth-dose vaccination, and 13% had received hepatitis B immunoglobulin along with the full vaccination regimen. Less than 1% of mothers with a high viral load had received antiviral therapy to reduce mother-to-child transmission. Interpretation: Our estimate of HBV prevalence in 2016 differs from previous studies, potentially because we took into account the effect of infant prophylaxis and early childhood vaccination, as well as changing prevalence over time. Although some regions are well on their way to meeting prophylaxis and prevalence targets, all regions must substantially scale-up access to diagnosis and treatment to meet the global targets. Funding: John C Martin Foundation. © 2018 Elsevier Ltd

Published
2018

49. Calcium-doping effects on photovoltaic response and structure in multiferroic BiFeO3 ceramics.

Author

Tu, C. S., Hung, C.-M., Xu, Z.-R., Schmidt, V. H., Ting, Y., Chien, R. R., Peng, Y.-T., and Anthoninappen, J.

Subjects
PHOTOVOLTAIC effect, CERAMICS, INDIUM tin oxide, HETEROSTRUCTURES, CLAY
Abstract

Photovoltaic (PV) effects, power-conversion efficiencies, and structures have been systematically measured in (Bi1-xCax)FeO3-δ ceramics for x = 0.05, 0.10, and 0.15. The heterostructures of indium tin oxide (ITO) film/(Bi1-xCax)FeO3-δ ceramics/Au film exhibit significant PV effects under illumination of λ = 405 nm. The maximum power-conversion efficiency in the ITO/(Bi0.90Ca0.10)FeO2.95 (BFO10C)/Au can reach 0.0072%, which is larger than 0.0025% observed in the graphene/polycrystalline BFO/Pt films [Zang et al., Appl. Phys. Lett. 99, 132904 (2011)]. A theoretical model based on optically excited current in the depletion region between ITO film and Ca-doped BFO ceramics is used to describe the I-V characteristic, open-circuit voltage, and short-circuit current density as a function of illumination intensity. This work suggests that the Ca-substitution can reduce the rhombohedral distortion and stabilize the single-phase structure. [ABSTRACT FROM AUTHOR]

Published
2013
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