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To explore whether different polyvinylpyrrolidone (PVP) concentrations affect the results of intracytoplasmic sperm injection (ICSI), a prospective study was conducted for 194 couples undergoing 210 ICSI therapy cycles. These cycles were divided into three groups (10, 7 and 5% groups) using the corresponding concentration of PVP for sperm immobilization. The main outcome measures were analyzed. Results indicated that, with a decrease in PVP concentrations, all of the main outcome measures increased. In particular, the high-quality cleavage embryo rate in the 7% group was significantly lower than in the 5% group (P < 0.01), and the cleavage, high-quality cleavage embryo, and high-quality blastocyst rates in the 5% group were significantly higher than those in the 10% group (all P < 0.001). For high-/intermediate-quality semen, all of the main outcome measures were significantly increased with 5% PVP. For the poor-quality semen, only the high-quality cleavage embryo and high-quality blastocyst rates were significantly higher in the 5% group. Therefore, lowering PVP concentrations greatly promoted the development of embryos in ICSI cycles, with an optimal concentration of 5% for ICSI.
Androgenetic embryonic stem (AgES) cells offer a possible tool for patient-specific pluripotent stem cells that will benefit genomic imprinting studies and clinic applications. However, the difficulty in producing androgenetic embryos and the unbalanced expression of imprinted genes make the therapeutic applicability of AgES cells uncertain. In this study, we produced androgenetic embryos by injecting two sperm into an enucleated metaphase II (MII) oocyte. By this method, 88.48% of oocytes survived after injection, and 20.24% of these developed to the blastocyst stage. We successfully generated AgES cell lines from the androgenetic embryos and assayed the expression of imprinted genes in the cell lines. We found that the morphological characteristics of AgES cells were similar to that of fertilized embryonic stem cells (fES), such as expression of key pluripotent markers, and generation of cell derivatives representing all three germ layers following in vivo and in vitro differentiation. Furthermore, activation of paternal imprinted genes was detected, H19, ASC12 and Tss3 in AgES cell activation levels were lower while other examined genes showed no significant difference to that of fES cells. Interestingly, among examined maternal imprinted genes, only Mest and Igf2 were significantly increased, while levels of other detected genes were no different to that of fES cells. These results demonstrated that activation of some paternal imprinted genes, as well as recovery of maternal imprinted genes, was present in AgES cells. We differentiated AgES cells into a beating embryoid body in vitro, and discovered that the AgES cells did not show significant higher efficiency in myocardial differentiation potential.
An important aspect of composite materials concerns the technology by which they are produced. Depending on the nature of matrix and fibre, and the required architecture of fibre distribution, production at reasonable cost and with suitable microstructural quality can present a challenge. In most cases, manufacture of the final component and production of the composite material are carried out at the same time. This gives scope for optimal fibre placement and distribution of orientations, but also requires that the mechanical requirements of the application be well understood and that the processing route be tailored accordingly. Fabrication procedures for most commercially important (fibre-reinforced polymer) composites are technically mature, but there are some types of composite for which processing routes are still under development.
Much effort has been devoted to improving the efficiency of animal cloning. The aim of this study was to investigate the effect of BRG1 contained in Xenopus egg extracts on the development of cloned mouse embryos. The results showed that mouse NIH/3T3 cells were able to express pluripotent genes after treatment with egg extracts, indicating that the egg extracts contained reprogramming factors. After co-injection of Xenopus egg extracts and single mouse cumulus cells into enucleated mouse oocytes, statistically higher pronucleus formation and development rates were observed in the egg Extract− co-injected group compared with those in the no egg extract-injected (NT) group (38–66% vs 18–34%, P<0.001). Removal of BRG1 protein from Xenopus egg extracts was conducted, and the BRG1-depleted extracts were co-injected with single donor cells into recipient oocytes. The results showed that the percentages of pronucleus formation were significantly higher in both BRG1-depleted and BRG1-intact groups than that in the nuclear transfer (NT) group (94, 64% vs 50%, P<0.05). Furthermore, percentages in the BRG1-depleted group were even higher than in the BRG1-intact group (94% vs 64%). More confined expression of Oct4 in the inner cell mass (ICM) was observed in the blastocyst derived from the egg extract-injected groups. However, Nanog expression was more contracted in the ICM of cloned blastocysts in the BRG1-depleted group than in the BGR1-intact group. Based on the present study, BRG1 might not play an essential role in reprogramming, but the factors enhancing pronucleus formation and development of cloned mouse embryos are contained in Xenopus egg extracts.
Greenhouse gas emissions abatement, negative emissions technologies, and adaptation are not, and most likely will not, be enough to prevent dangerous climate change and its deleterious impacts on humans, other species, and ecosystems. Some scientists and others are increasingly considering and researching solar geoengineering, which would reflect or block some of the sun's incoming solar radiation, as a potential complementary response. This introductory chapter offers an initial explanation of climate change and solar geoengineering, including its leading proposed techniques of stratospheric aerosol injection, marine cloud brightening, and cirrus cloud thinning. Solar geoengineering should be taken seriously, as its governance is both important and challenging. Among the major challenges is that solar geoengineering presents a high-stakes risk-risk tradeoff under conditions of great uncertainty. Another is that although earlier governance can be more effective, little is then known of such an emerging technology’s salient characteristics. The chapter outlines the topics covered by the remainder of the book and makes the author’s prior assumptions explicit.
Solar geoengineering is being considered and researched as a potential response to anthropogenic climate change. After exploring the causes and risks of climate change and other responses to it, this chapter describes solar geoengineering’s history and proposed methods, including stratospheric aerosol injection, marine cloud brightening, and cirrus cloud thinning. The current evidence regarding their potential capabilities, costs, and technical feasibility is presented. Evidence from models and natural analogs indicates that a moderate deployment of solar geoengineering would globally reduce climate change. It also appears to be technically feasible, rapid in its effects, inexpensive in its direct deployment costs, and reversible. Among solar geoengineering’s physical risks are imperfect compensation of climatic changes and consequent residual climatic anomalies, delayed recovery of stratospheric ozone, and irresolvable uncertainty. Social challenges include decision-making regarding deployment, problematic uni- or minilateral implementation, strained international relations, displacement of emissions abatement, biased future decision-making, and disagreement regarding ethics.
Our objective was to assess the effect of benchtop incubators with low oxygen concentrations on the clinical and embryological parameters of our patients. We conducted a prospective, randomized, opened controlled trial on infertile patients in stimulated cycles. In total, 738 infertile patients were assessed for eligibility and, after final exclusions, 230 patients were allocated either to a 5% O2 group (benchtop incubator) or a 20% O2 group (classic incubator). Finally, 198 patients in the 5% O2 group and 195 in the 20% O2 group were analysed. The outcomes measured were fertilization rate, clinical pregnancy rate, and live birth rate. The primary outcome – live birth rate per all transfers – did not show any improvement in the 5% oxygen group over the 20% oxygen group (25.3% versus 22.6%, P=0.531), but the number of day 5 blastocysts was significantly higher (P=0.009). Fertilization rate did not show any beneficial effect of reduced oxygen (5%) (73.4%±22.4% versus 74.6%±24.0%, P=0.606) per all transfers but there was statistically significant difference in the day 5 SET subgroup (85.3±15.1 versus 75.1±17.5; P=0.004). Clinical pregnancy rate showed results in favour of the 5% oxygen group for all subgroups (day 3: 23.7% versus 21.1%, P=0.701; day 5 SET: 35.0% versus 30.6%. P=0.569) but showed statistical significance only in the day 5 SET subgroup (51.1% versus 29.8%; P=0.038). Culturing of embryos in benchtop incubators under low oxygen produced more blastocysts and therefore was a better alternative for embryo selection, which resulted in higher pregnancy rates. To achieve higher live birth rates, embryo quality is not the only factor.
Hypoimmunity and numerous stresses are two major challenges in broiler industry. Nutrient intervention at the specific time of embryonic stage is a feasible way to improve animal performance. This study was conducted to investigate the possible effects of in ovo feeding (IOF) of vitamin C at embryonic age 15th day (E15) on growth performance, antioxidation and immune function of broilers. A total of 240 broiler fertile eggs were randomly divided into two groups (0 and 3 mg injected dose of vitamin C at E15), and new-hatched chicks from each treatment were randomly allocated into six replicates with 10 chicks per replicate after incubation. The results indicated that in ovo vitamin C injection improved the hatchability (P < 0.05) and increased immunoglobulin M (IgM) (at the broiler’s age 1st day, D1), IgG and IgM concentrations (D21), as well as lysozyme activity (D21, P < 0.05) and total antioxidant capacity (D42, P < 0.01) in plasma of broilers. On D21, the splenic expression level of DNA methyltransferase 1 (DNMT1) was up-regulated in vitamin C (VC) group, whereas interleukin (IL)-6, interferon-γ, ten-eleven translocation protein 1 and thymine-DNA glycosylase were down-regulated (P < 0.05). On D42, in ovo vitamin C injection up-regulated splenic expression levels of DNMT1, DNA methyltransferase 3B (DNMT3B) and growth arrest and DNA-damage-inducible protein beta (P < 0.05), whereas down-regulated splenic expression levels of IL-6, tumour necrosis factor-α and methyl-CpG-binding domain protein 4 (P < 0.05). Our findings suggested that IOF of 3 mg vitamin C at E15 could improve, to some extent, the antioxidant activity and immune function in plasma, corresponding with the lower expression of pro-inflammatory cytokines in spleen. However, IOF of vitamin C leading to the changes in the expression of DNA methyltransferases and demethylases may suggest an increased trend of DNA methylation level in spleen and whether DNA methylation variation is associated with the lower expression of pro-inflammatory cytokines in spleen warrants future study.
A new computerized instrument (the Multimedia Behavioral Avoidance Test, or MBAT) for blood-injury-injection phobia (BII) assessment is presented. Analogous stimuli such as images and videos can also elicit anxiety responses; thus, they can be used for the assessment of phobia. The MBAT was applied to participants via computer, and subjective anxiety responses and time latency were recorded. The MBAT was composed of 30 original images and 30 videos related to blood, injury and injections. The MBAT was compared with other pencil-and-paper questionnaires for BII phobia, and heart rate was also measured with a pulsioximeter. The participants included 160 students and professionals (34.5% males, 65.6% females; mean 28.6 years old). The results showed a high reliability for internal consistency in images and videos (α = .98 both), with a single factor that groups all the items. In addition, the MBAT had high concurrent validity (r = .78 to .85) with the different anxiety scales compared. The MBAT diagnosed 12 participants with possible BII phobia. It is a useful instrument in the assessment of this kind of phobia because it is easier and quicker than pencil-and-paper questionnaires, it uses more objective measurements, and it is useful in planning subsequent exposure with images and videos.
De Finetti’s optimal dividend problem has recently been extended to the case when dividend payments can be made only at Poisson arrival times. In this paper we consider the version with bail-outs where the surplus must be nonnegative uniformly in time. For a general spectrally negative Lévy model, we show the optimality of a Parisian-classical reflection strategy that pays the excess above a given barrier at each Poisson arrival time and also reflects from below at 0 in the classical sense.
A numerical simulation has been carried out to investigate the effects of leading edge blowing upon heat alleviation on the surface of hypersonic vehicles. The initial phase of this work deals with the ability of the present CFD-based techniques to solve hypersonic flow field past blunt-nosed vehicles at hypersonic speeds. Towards this end, the authors selected three re-entry vehicles with published flow field data against which the present computed results could be measured. With increasing confidence on the numerical simulation techniques to accurately resolve the hypersonic flow, the boundary condition at the solid blunt surface was then equipped with the ability to blow the flow out of the solid boundary at a rate of at least 0.01–0.1 times the free stream (ρ∞u∞) mass flow rate. The numerical iterative procedure was then progressed until the flow at the surface matched this new ‘inviscid like’ boundary condition. The actual matching of the flow field at the ejection control surface was achieved by iterating the flow on the adjacent cells until the flow conformed to the conditions prescribed at the control surface. The conditions at the surface could be submitted as a ρ∞u∞ at the surface or could be equipped as a simple static pressure condition providing the desired flow rate. The comparison between the present engineering approach and the experimental data presented in this study demonstrate its ability to solve complex problems in hypersonic.
Safety and tolerability of long-term treatment with the long-acting antipsychotic aripiprazole lauroxil (AL) were evaluated in patients with schizophrenia.
This was an international, multicenter, phase 3, 52-week safety study of 2 fixed doses of AL (441 mg or 882 mg intramuscular every 4 weeks). Safety endpoints included adverse events (AEs) and extrapyramidal symptoms (EPS) including akathisia, injection-site reactions (ISRs), and clinically relevant changes in metabolic and endocrine values.
Of 478 patients entering this study, 236 (49%) continued from a previous 12-week, phase 3 efficacy study of AL, and 242 (51%) were newly enrolled. Overall, 77% and 23% of patients received AL 882 mg (N = 368) and 441 mg (N = 110), respectively. AEs occurred in 50.4% of patients; most were mild (28.7%) or moderate (18.2%). The most common AEs were insomnia (8.4%) and increased weight (5.0%). Akathisia was reported as an AE in 3.8% of the overall population, with higher rates in patients initiating AL on study entry than those continuing on AL. EPS-related AEs occurred in 9.4% of patients, and AEs related to metabolic parameters were reported in 4.6% of patients. Weight gain was minimal (0.8 kg), and no clinically relevant changes were observed for metabolic parameters. The overall incidence of ISRs was 3.8%; most were associated with the initial injections in patients receiving their first injection in this study.
Long-term treatment with AL is generally well tolerated, with a safety profile consistent with that of oral aripiprazole. It is a suitable option for patients with schizophrenia.
In this work, we propose a capital injection strategy which is periodically implemented based on the number of claims in the classical Poisson risk model. Especially, capital injection decisions are made at a predetermined accumulated number of claim instants, if the surplus is lower than a minimum required level. There appears to be a similar problem found in reliability theory such that preventive maintenance policies are performed at certain shock numbers. Assuming a combination of exponentials for the claim severities, we first derive an explicit expression for the discounted density of the surplus level after a certain number of claims if ruin has not yet occurred. Utilising this result, we study the expected total discounted capital injection until the first ruin time. To solve the differential equation associated with this quantity, we analyse an extended Lundberg’s fundamental equation. Similarly, an expression for the Laplace transform of the time to ruin is also explicitly found. Finally, we illustrate the applicability of the present capital injection strategy and methodologies through various numerical examples. In particular, for exponential claim severities, some optimal capital injection strategy which minimises the expected capital spending per unit time is numerically studied.
Since 1997, execution in China has been increasingly performed by lethal injection. The current criteria for determination of death for execution by lethal injection (cessation of heartbeat, cessation of respiration, and dilated pupils) neither conform to current medical science nor to any standard of medical ethics. In practice, death is pronounced in China within tens of seconds after starting the lethal injection. At this stage, however, neither the common criteria for cardiopulmonary death (irreversible cessation of heartbeat and breathing) nor that of brain death (irreversible cessation of brain functions) have been met. To declare a still-living person dead is incompatible with human dignity, regardless of the processes following death pronouncement. This ethical concern is further aggravated if organs are procured from the prisoners. Analysis of postmortem blood thiopental level data from the United States indicates that thiopental, as used, may not provide sufficient surgical anesthesia. The dose of thiopental used in China is kept secret. It cannot be excluded that some of the organ explantation surgeries on prisoners subjected to lethal injection are performed under insufficient anesthesia in China. In such cases, the inmate may potentially experience asphyxiation and pain. Yet this can be easily overlooked by the medical professionals performing the explantation surgery because pancuronium prevents muscle responses to pain, resulting in an extremely inhumane situation. We call for an immediate revision of the death determination criteria in execution by lethal injection in China. Biological death must be ensured before death pronouncement, regardless of whether organ procurement is involved or not.
Solar wind kinetic energy gets transferred into the Earth’s magnetosphere as a result of dynamo action between magnetosphere and solar wind. Energy is then dissipated among various dissipation channels in the MI system. In the present study, energetics of 59 intense geomagnetic storms are analyzed for the period between 1986 and 2015, which covers the three consecutive solar cycles SC 22, 23 and 24. The average solar wind energy impinging the MI system is estimated using Epsilon parameter, the coupling function. Moreover, the relative importance of different energy sinks in the MI system are quantified and is found that more than 60% of solar wind energy is dissipated in the form of ionospheric Joule heating.
A high power laser system was used to drive the ignition of inertial confinement fusion (ICF), of which the high energy, the uniform focal spot, the accurate laser waveform, and the synchronization between the laser beams are key parameters. To accomplish this, global laser characteristics control should be assured, which was the main purpose of the injection laser system. In this paper, the key technological progress involved in the improvement of the performance of the injection laser of SG-II is reported, including frequency domain control, time domain control, near-field spatial shaping, pre-amplifier technology, and the optical parametric chirped pulse amplification pump source.
In the rapidly expanding literature on the ethics of climate engineering, a lot has been made of the fact that stratospheric aerosol injection would for the first time create a world whose climate had been intentionally shaped by deliberate human decisions. Intention has always mattered in ethics. Due to the importance of intention in assigning culpability for harms, one might expect that the moral responsibility for any harms created during an attempt to reconstruct the global climate using stratospheric aerosols would be considerable. This article investigates such an expectation by making a comparison between the culpability for any unintended harms resulting from stratospheric aerosol injection and culpability for the unintended harms already taking place due to carbon emissions. To make this comparison, both types of unintended harms are viewed through the lens of the doctrine of double effect. The conclusion reached goes against what many might expect. The article closes by suggesting that a good way to read this surprising conclusion is that it points toward the continuing moral importance of prioritizing emission reductions.
Christopher J. Preston's use of the doctrine of double effect to claim that hypothetical climate engineers might very well be less culpable for climate harms than those who continue to emit greenhouse gases is unpersuasive. His argument rests shakily on the ability to determine and quantify climate harms and to distinguish forensically between their causes. He is also largely silent about the distributional effects of these harms and their ethical and political ramifications.
In his article “Carbon Emissions, Stratospheric Aerosol Injection, and Unintended Harms,” Christopher J. Preston compares the culpability of carbon emitters versus that of geoengineers deploying stratospheric aerosol injection (SAI). This comparison relies on a parallel between carbon emitters and SAI deployers that requires both to be agents. However, both are not. While the harms of geoengineering will be caused by culpable agents acting intentionally, the harms connected to climate change emerge out of the uncoordinated actions of billions of people. Taken as a large group, carbon emitters cause harm but do not constitute an agent. Taken individually, carbon emitters are agents but do not cause the harms of climate change. As a result, the parallel collapses, and Preston's “surprising” conclusion is one that he is not entitled to reach.
In order to advance a neatly deductive argument, Christopher J. Preston must make a number of assumptions and framing decisions that exclude important practical points from the scope of his analysis. We do not criticize him for doing so, as these simplifications allow him to advance a concise argument about an ethically complex subject. However, as scholars of politics and law, we are interested in what this ethical argument means—and does not mean—for the messy politics of climate engineering. Accordingly, in our response we unpack the political implications of some of Preston's assumptions and framing decisions in an effort to add a layer of practical richness to the abstraction of Preston's analysis.