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التخفيف من حدة الفقر في الصين المعاصرة
استنادا إلى نظرة عامة على أوضاع الفقر، يقدم هذا الكتاب مسار التخفيف من حدة الفقر والتنمية في الصين، ويشرح نموذج التنمية والتخفي من حدة الفقر بخصائص صينية والتمسك بمباديء (سيطرة الحكومة ومشاركة المجتمع والاعتماد على الذات والتنمية الموجهة والتنمية الشاملة) كما يقدم الكتاب تلخيصا شاملا لإنجازات الصين العظيمة وخبراتها الهامة وإسهاماتها الرئيسية في قضية التخفيف من حدة الفقر في العالم، ويعرض بإيجاز نظرات وممارسات التخفيف المستهدف من الفقر في العصر الجديد من أجل توفير مراجع لكسب المعركة ضد الفقر في الصين وقضية التخفيف من حدة الفقر في العالم.
Book
Partially Ionized Gas at Equilibrium Powered by Ultraviolet Irradiation
We study the formation of a partially ionized zone behind the usual H II zone in photoionized gas for a density intermediate between ordinary H II regions and active galactic nucleus broad-line regions, and without X-rays. While Lyman continuum photons are depleted before reaching this zone, Balmer continuum photons can ionize the n = 2 hydrogen atoms as those are pumped by scattering-trapped Lyα photons. Lyα photons need to be replenished in a steady state, but fast radiative cooling at high gas temperature makes replenishment through electron collisional excitation of n = 2 inefficient. Independent of the temperature, Raman scattering of incident continuum photons on the Lyman-series damping wings injects Lyα photons in the line core and pumps the n = 2 state, which helps realize a partially ionized equilibrium at 5000–7000 K. Since the ratio between the incident radiation flux and gas density is limited by the dynamic effects of radiation pressure, significant ionization fraction is only realized at densities nH ≳ 107 cm−3. A large Hα/Hβ line ratio results from such partially ionized gas, as large Balmer line optical depths enhance the n = 3 population relative to higher n states. Partial ionization also provides the ideal condition for internally forming an intense and very broad Lyα line, which can power strong fluorescent metal emission lines observed from the Weigelt blobs of η Carinae in the Galaxy, and from a candidate young super star cluster in the Cosmic Noon Sunburst galaxy. This phenomenon may also have implications for understanding the spectra of high-z galaxies that show unusually dense ionized gas.
Journal Article
A Young Super Star Cluster Powering a Nebula of Retained Massive Star Ejecta
We suggest that “Godzilla” of the lensed Sunburst galaxy (z = 2.37) is a young super star cluster powering a nebula of gravitationally trapped stellar ejecta. Employing Hubble Space Telescope photometry and spectroscopy from the Very Large Telescope (VLT) MUSE and VLT/X-Shooter, we infer the physical and chemical properties of the cluster and nebula, finding that Godzilla is young, 4–6 Myr; massive, 2 × 106 M ⊙ (1000/μ); of stellar metallicity, Z ≃ 0.25 Z ⊙; and has a compact far-UV component of ≲1 pc (1000/μ), where μ is the flux magnification factor. The gas is significantly enriched with N and He, indicating stellar wind material, and has highly elevated O relative to the stellar metallicity, indicating entrainment of core-collapse supernova (CCSN) ejecta. The high density, n e ≃ 107−8 cm−3, implies a highly pressurized intracluster environment. We propose that the pressure results from CCSN-driven supersonic turbulence in warm, self-shielding gas, which has accumulated in the cluster center after runaway radiative cooling and is dense enough to resist removal by CCSNe. The nebula gas shows subsolar C/O, Ne/O, and Si/O, which may reflect the CCSN element yields for initial stellar masses >40 M ⊙. A comparison to element yield synthesis models for young star clusters shows that the gas abundances are consistent with complete retention and mixture of stellar winds and CCSN ejecta until the inferred cluster age. The inferred O and He enhancement may have implications for the formation of multiple stellar populations in globular clusters, as stars formed from this gas would contradict the observed abundances of second-population stars.
Journal Article
Effects of Subhalos on Interpreting Highly Magnified Sources Near Lensing Caustics
Large magnification factors near gravitational lensing caustics of galaxy-cluster lenses allow the study of individual stars or compact stellar associations at cosmological distances. We study how the presence of sub-galactic subhalos, an inevitable consequence of cold dark matter, can alter the property of caustics and hence change the interpretation of highly magnified sources that lie atop them. First, we consider a galaxy-cluster halo populated with subhalos sampled from a realistic subhalo mass function calibrated to N-body simulations. Then, we compare a semianalytical approximation and an adaptive ray-shooting method that we employ to quantify the property of the caustics. As a case study, we investigate Earendel, a z = 6.2 candidate of magnified single- or multiple-star system with a lone lensed image atop the critical curve in the Sunrise Arc. We find that the source size constraint (≲0.3 pc) previously derived from macrolens models should be relaxed by a factor of a few to 10 when subhalos are accounted for, therefore allowing the possibility of a compact star cluster. The subhalos could introduce an astrometric perturbation that is ≲0 .″ 5, which does not contradict observation. These conclusions are largely robust to changes in the subhalo population. Subhalos therefore should be seriously accounted for when interpreting the astrophysical nature of similar highly magnified sources uncovered in recent high-z observations.
Journal Article
Sirtuin 3 deficiency exacerbates diabetic cardiomyopathy via necroptosis enhancement and NLRP3 activation
Sirtuin 3 (SIRT3) is a potential therapeutic target for cardiovascular, metabolic, and other aging-related diseases. In this study, we investigated the role of SIRT3 in diabetic cardiomyopathy (DCM). Mice were injected with streptozotocin (STZ, 60 mg/kg, ip) to induce diabetes mellitus. Our proteomics analysis revealed that SIRT3 expression in the myocardium of diabetic mice was lower than that of control mice, as subsequently confirmed by real-time PCR and Western blotting. To explore the role of SIRT3 in DCM, SIRT3-knockout mice and 129S1/SvImJ wild-type mice were injected with STZ. We found that diabetic mice with SIRT3 deficiency exhibited aggravated cardiac dysfunction, increased lactate dehydrogenase (LDH) level in the serum, decreased adenosine triphosphate (ATP) level in the myocardium, exacerbated myocardial injury, and promoted myocardial reactive oxygen species (ROS) accumulation. Neonatal rat cardiomyocytes were transfected with SIRT3 siRNA, then exposed to high glucose (HG, 25.5 mM). We found that downregulation of SIRT3 further increased LDH release, decreased ATP level, suppressed the mitochondrial membrane potential, and elevated oxidative stress in HG-treated cardiomyocytes. SIRT3 deficiency further raised expression of necroptosis-related proteins including receptor-interacting protein kinase 1 (RIPK1), RIPK3, and cleaved caspase 3, and upregulated the expression of inflammation-related proteins including NLR family pyrin domain-containing protein 3 (NLRP3), caspase 1 p20, and interleukin-1β both in vitro and in vivo. Collectively, SIRT3 deficiency aggravated hyperglycemia-induced mitochondrial damage, increased ROS accumulation, promoted necroptosis, possibly activated the NLRP3 inflammasome, and ultimately exacerbated DCM in the mice. These results suggest that SIRT3 can be a molecular intervention target for the prevention and treatment of DCM.
Journal Article
Under Einstein’s Microscope: Measuring Properties of Individual Rotating Massive Stars from Extragalactic Microcaustic Crossings
Highly magnified stars residing in caustic crossing lensed galaxies at z ≃ 0.7–1.5 in galaxy cluster lensing fields inevitably exhibit recurrent brightening events as they traverse a microcaustic network cast down by foreground intracluster stars. The detectable ones belong to nature’s most massive and luminous class of stars, with evolved blue supergiants being the brightest ones at optical wavelengths. Considering single stars in this work, we study to what extent intrinsic stellar parameters are measurable from multifilter light curves, which can be obtained with optical/near-IR space telescopes during one or multiple caustic crossing events. We adopt a realistic model for the axisymmetric surface brightness profiles of rotating O/B stars and develop a numerical lensing code that treats finite source size effects. With a single microcaustic crossing, the ratio of the surface rotation velocity to the breakup value is measurable to a precision of ∼0.1–0.2 for feasible observation parameters with current space telescopes, with all unknown intrinsic and extrinsic parameters marginalized over and without a degeneracy with inclination. Equatorial radius and bolometric luminosity can be measured to 1/3 and 2/3 of the fractional uncertainty in the microcaustic strength, for which the value is not known at each crossing but an informative prior can be obtained from theory. Parameter inference precision may be further improved if multiple caustic crossing events for the same lensed star are jointly analyzed. Our results imply new opportunities to survey individual massive stars in star formation sites at z ≃ 0.7–1.5 or beyond.
Journal Article
Nitrogen-enriched, Highly Pressurized Nebular Clouds Surrounding a Super Star Cluster at Cosmic Noon
Strong lensing offers a precious opportunity for studying the formation and early evolution of super star clusters that are rare in our cosmic backyard. The Sunburst Arc, a lensed Cosmic Noon galaxy, hosts a young super star cluster with escaping Lyman continuum radiation. Analyzing archival Hubble Space Telescope images and emission line data from Very Large Telescope/MUSE and X-shooter, we construct a physical model for the cluster and its surrounding photoionized nebula. We confirm that the cluster is ≲4 Myr old, is extremely massive M ⋆ ∼ 107 M ⊙, and yet has a central component as compact as several parsecs, and we find a gas-phase metallicity Z = (0.22 ± 0.03)Z ⊙. The cluster is surrounded by ≳105 M ⊙ of dense clouds that have been pressurized to P ∼ 109 K cm−3 by perhaps stellar radiation at within 10 pc. These should have large neutral columns N HI > 1022.8 cm−2 to survive rapid ejection by radiation pressure. The clouds are likely dusty as they show gas-phase depletion of silicon, and may be conducive to secondary star formation if N HI > 1024 cm−2 or if they sink farther toward the cluster center. Detecting strong [N iii]λ λ 1750,1752, we infer heavy nitrogen enrichment log(N/O)=−0.21−0.11+0.10 . This requires efficiently retaining ≳500 M ⊙ of nitrogen in the high-pressure clouds from massive stars heavier than 60 M ⊙ up to 4 Myr. We suggest a physical origin of the high-pressure clouds from partial or complete condensation of slow massive star ejecta, which may have an important implication for the puzzle of multiple stellar populations in globular clusters.
Journal Article
Shortened key growth periods of soybean observed in China under climate change
Phenology is an important indicator of global climate change. Revealing the spatiotemporal characteristics of crop phenology is vital for ameliorating the adverse effects of climate change and guiding regional agricultural production. This study evaluated the spatiotemporal variability of soybean’s phenological stages and key growth periods, and assessed their sensitivity to key climatic factors, utilizing a long-term dataset (1992–2018) of soybean phenology and associated meteorological data collected at 51 stations across China. The results showed that (1) during the soybean growing seasons from 1992 to 2018, the average temperature (0.34 ± 0.09 ℃ decade
−1
) and cumulative precipitation (6.66 ± 0.93 mm decade
−1
) increased, but cumulative sunshine hours (− 33.98 ± 1.05 h decade
−1
) decreased. (2) On a national scale, dates of sowing, emergence, trifoliate, anthesis, and podding of soybean were delayed, while the maturity date showed an advancing trend. The vegetative growth period (− 0.52 ± 0.24 days decade
−1
) and whole growth period (− 1.32 ± 0.30 days decade
−1
) of soybean were shortened, but the reproductive growth period (0.05 ± 0.26 days decade
−1
) was slightly extended. Trends in soybean phenological stages and key growth periods diverged in regions. Soybean phenological stages were delayed in Huang-Huai-Hai soybean zone, whereas advanced in southern soybean zone. Moreover, the key growth periods were greatly shortened in northern soybean zone. (3) In general, the sensitivity of soybean key growth periods to temperature was negative, whereas those to precipitation and sunshine hours differed among regions. In particular, most phenological stages were negatively sensitive to sunshine hours. Our results will provide scientific support for decision-making in agricultural production practices.
Journal Article
Pan evaporation estimation by relevance vector machine tuned with new metaheuristic algorithms using limited climatic data
This study investigates the feasibility of a relevance vector machine tuned with improved Manta-Ray foraging optimization (RVM-IMRFO) in predicting monthly pan evaporation using limited climatic input data (e.g. temperature). The accuracy of the RVM-IMRFO was evaluated by comparing it with RVM tuned by gray wolf optimization, RVM tuned with a whale optimization algorithm, and RVM tuned with Manta Ray foraging optimization concerning root mean square errors (RMSE), mean absolute errors (MAE), determination coefficient (R
2
) and Nash-Sutcliffe Efficiency (NSE) and new graphical inspection methods. The models were assessed using data acquired from two stations in China and data were divided into three equal parts. The models were tested using each data set. The application outcomes revealed that the proposed algorithm considerably improved the accuracy of a single RVM in monthly pan evaporation prediction by an average improvement in RMSE, MAE, R
2
, and NSE as 27.65%, 27.53%, 8.40% and 8.63%, respectively. It is also found that the proposed algorithm showed significant dominance over others models with respect to improvement in overall mean values of RMSE, MAE, R
2
, and NSE statistics from 34.7-38.2 to 18.2-19.5, 36.2-36.4 to 19.1-18.5, 12.5-13.8 to 3.6-3.7, and 12.4-14.6 to 3.6-3.9%, for both climatic stations, respectively. Importing extraterrestrial radiation and periodicity component (month number of the data) into the model inputs improved the prediction accuracy of the implemented models. The outcomes revealed that the RVM-IMRFO performed superior to the other methods in predicting monthly pan evaporation using only temperature data which is essential, especially in developing countries where other climatic data are missing or unavailable. The RVM model was also compared with standard multi-layer perceptron neural networks (MLPNN) and found that the first acts better than the latter in monthly pan evaporation prediction.
Journal Article
Prognostic implications of systemic immune-inflammation index and systemic inflammation response index in hemodialysis patients
Objectives
Patients undergoing hemodialysis (HD) face high mortality, mainly from cardiovascular disease (CVD), infections, and dialysis withdrawal. Systemic inflammation contributes significantly to these outcomes. This study aimed to examine the associations between the systemic immune-inflammation index (SII) and systemic inflammation response index (SIRI) with all-cause, CVD, and infection-related mortality in HD patients, and to evaluate their prognostic value.
Methods
We conducted a retrospective analysis of 1190 HD patients recruited between January 2012 and December 2016. Kaplan-Meier survival curves, Cox regression analysis, and restricted cubic spline (RCS) models were employed to explore the associations between SII, SIRI, and all-cause, CVD, and infection-related mortality. In addition, receiver operating characteristic (ROC) curves was used to determine the predictive accuracy of SII and SIRI.
Results
Among the 1190 patients (median age 62.0 years; 64.0% male), the all-cause mortality rate was 38.2%, while the CVD mortality rate was 16.9%. Adjusted Cox regression analyses revealed that patients in the highest SIRI quartile (quartile 4) had significantly elevated risks of all-cause (hazard ratio [HR] 2.29, 95% CI 1.38–3.80,
P
= 0.001), CVD (HR 3.78, 95% CI 1.43–10.01,
P
= 0.007), and infection-related mortality (HR 2.42, 95% CI 1.70–3.01,
P
< 0.001) compared to those in the lowest SIRI quartile. Similar associations were found for SII (
P
< 0.001). Kaplan-Meier curves demonstrated comparable results. RCS analysis revealed nonlinear relationships between SII, SIRI, and mortality risk (
P
< 0.05). ROC analysis highlighted that Both SII and SIRI demonstrated moderate to strong prognostic value, with SIRI consistently offering the best risk stratification.
Conclusions
Elevated levels of SII and SIRI are linked to higher risks of all-cause, CVD, and infection-related mortality in HD patients. SIRI appears to be a more reliable predictor of mortality risk. Future studies should explore the underlying mechanisms and validate the predictive value of SII and SIRI for mortality risk among HD patients.
Clinical trail number
Not applicable.
Journal Article