New Methods for Evaluating Energy Infrastructure Development Risks.

Many energy technologies that can provide reliable, low-carbon electricity generation are confined to nations that have access to robust technical and economic capabilities, either on their own or through geopolitical alliances. Equally important, these nations maintain a degree of institutional capacity that could lower the risks associated with deploying emergent energy technologies such as advanced nuclear or carbon capture and storage. The complexity, expense, and scrutiny that come with building these facilities make them infeasible choices for most nations. This paradigm is slowly changing, as the pressing need for low-carbon electricity generation and ongoing efforts to develop modular nuclear and carbon capture technologies have opened the door for potentially wider markets, including in nations without substantial institutional capacity. Here, using advanced nuclear technologies as our testbed, we develop new methods to evaluate national readiness for deploying complex energy infrastructure. Specifically, we use Data Envelopment Analysis-a method that eliminates the need for expert judgment-to benchmark performance across nations. We find that approximately 80% of new nuclear deployment occurs in nations that are in the top two quartiles of institutional and economic performance. However, 85% of potential low-carbon electricity demand growth is in nations that are in the bottom two quartiles of performance. We offer iconic paradigms for deploying nuclear power in each of these clusters of nations if the goal is to mitigate risk. Our research helps redouble efforts by industry, regulators, and international development agencies to focus on areas where readiness is low and risk correspondingly higher.

The anterior gradient homologue 2 (AGR2) co-localises with the glucose-regulated protein 78 (GRP78) in cancer stem cells, and is critical for the survival and drug resistance of recurrent glioblastoma: in situ and in vitro analyses.

BACKGROUND: Glioblastomas (GBs) are characterised as one of the most aggressive primary central nervous system tumours (CNSTs). Single-cell sequencing analysis identified the presence of a highly heterogeneous population of cancer stem cells (CSCs). The proteins anterior gradient homologue 2 (AGR2) and glucose-regulated protein 78 (GRP78) are known to play critical roles in regulating unfolded protein response (UPR) machinery. The UPR machinery influences cell survival, migration, invasion and drug resistance. Hence, we investigated the role of AGR2 in drug-resistant recurrent glioblastoma cells. METHODS: Immunofluorescence, biological assessments and whole exome sequencing analyses were completed under in situ and in vitro conditions. Cells were treated with CNSTs clinical/preclinical drugs taxol, cisplatin, irinotecan, MCK8866, etoposide, and temozolomide, then resistant cells were analysed for the expression of AGR2. AGR2 was repressed using single and double siRNA transfections and combined with either temozolomide or irinotecan. RESULTS: Genomic and biological characterisations of the AGR2-expressed Jed66_GB and Jed41_GB recurrent glioblastoma tissues and cell lines showed features consistent with glioblastoma. Immunofluorescence data indicated that AGR2 co-localised with the UPR marker GRP78 in both the tissue and their corresponding primary cell lines. AGR2 and GRP78 were highly expressed in glioblastoma CSCs. Following treatment with the aforementioned drugs, all drug-surviving cells showed high expression of AGR2. Prolonged siRNA repression of a particular region in AGR2 exon 2 reduced AGR2 protein expression and led to lower cell densities in both cell lines. Co-treatments using AGR2 exon 2B siRNA in conjunction with temozolomide or irinotecan had partially synergistic effects. The slight reduction of AGR2 expression increased nuclear Caspase-3 activation in both cell lines and caused multinucleation in the Jed66_GB cell line. CONCLUSIONS: AGR2 is highly expressed in UPR-active CSCs and drug-resistant GB cells, and its repression leads to apoptosis, via multiple pathways.

Individual and Collective Strategies to Limit the Impacts of Large Power Outages of Long Duration.

As modern society becomes ever more dependent on the availability of electric power, the costs that could arise from individual and social vulnerability to large outages of long duration (LLD-outages) increases. During such an outage, even a small amount of power would be very valuable. This article compares individual and collective strategies for providing limited amounts of electric power to residential customers in a hypothetical New England community during a large electric power outage of long duration. We develop estimates of the emergency load required for survival and assess the cost of strategies to address outages that last 5, 10, and 20 days in either winter or summer. We find that the cost of collective solutions could be as much as 10 to 40 times less than individual solutions (less than $2 per month per home). However, collective solutions would require community-wide coordination, and if local distribution system lines are destroyed, only individual back-up systems could provide contingency power until those lines are repaired. Costs might be reduced if more robust distributed generation were employed that could be operated continuously with the ability to sell power back to the grid. Our cost-effectiveness analysis only assesses what could be done, developing estimates of preparedness cost. A decision about what should be done would require additional input from a range of stakeholders as well as some form of analytical deliberative process.

US nuclear power: The vanishing low-carbon wedge.

Nuclear power holds the potential to make a significant contribution to decarbonizing the US energy system. Whether it could do so in its current form is a critical question: Existing large light water reactors in the United States are under economic pressure from low natural gas prices, and some have already closed. Moreover, because of their great cost and complexity, it appears most unlikely that any new large plants will be built over the next several decades. While advanced reactor designs are sometimes held up as a potential solution to nuclear power's challenges, our assessment of the advanced fission enterprise suggests that no US design will be commercialized before midcentury. That leaves factory-manufactured, light water small modular reactors (SMRs) as the only option that might be deployed at significant scale in the climate-critical period of the next several decades. We have systematically investigated how a domestic market could develop to support that industry over the next several decades and, in the absence of a dramatic change in the policy environment, have been unable to make a convincing case. Achieving deep decarbonization of the energy system will require a portfolio of every available technology and strategy we can muster. It should be a source of profound concern for all who care about climate change that, for entirely predictable and resolvable reasons, the United States appears set to virtually lose nuclear power, and thus a wedge of reliable and low-carbon energy, over the next few decades.

Myocardial Protection by Blood-Based Del Nido versus St. Thomas Cardioplegia in Cardiac Surgery for Adults and Children.

BACKGROUND: St. Thomas (ST) and Del Nido (DN) cardioplegic solutions are widely used for myocardial protection during cardiac surgery. In 2016, our university hospital shifted from modified St. Thomas to Del Nido solution for both adult and pediatric cardiac surgery. This retrospective study was conducted to compare ST and DN solutions regarding surgical workflow and clinical outcome in pediatric and adult patients undergoing cardiac surgery. METHODS: We reviewed 220 patients who underwent cardiac surgery requiring cardioplegic arrest. Patients were categorized in 2 groups: ST (n = 110) and DN (n = 110). Each group included 60 pediatric and 50 adult patients. Demographic, intraoperative, and postoperative variables were collected. RESULTS: In pediatric patients, no significant difference was found between the 2 groups regarding clamping time, bypass time, need for defibrillation, inotropic score, postoperative ejection fraction (EF), period of mechanical ventilation, intensive care unit stay, or postoperative arrhythmias. One patient in the ST group required mechanical support by extracorporeal membrane oxygenation. We had 5 cases of pediatric mortality (3 in DN and 2 in ST, P = .64). In adult patients, significantly fewer patients in the DN group needed defibrillation than in the ST group. No significant difference was found regarding clamping time, inotropic score, or intraaortic balloon pump use. Mortality in adult patients was 6 cases (4 in ST group and 2 in DN group). CONCLUSION: DN cardioplegia solution is as safe as ST solution in pediatric and adult cardiac surgery. It has comparable results of myocardial protection and clinical outcome, with superiority regarding uninterrupted surgery and lower rate of defibrillation.

Eating disorders risk among medical students: a global systematic review and meta-analysis.

PURPOSE: Medical students appear to be a high-risk group to develop psychological problems including eating disorders (ED). The prevalence estimates of ED risk vary greatly between studies. This systematic review and meta-analysis was done to estimate the prevalence of ED risk among medical students. METHODS: An electronic search of EMBASE, MEDLINE, ProQuest and Google Scholar was conducted. Studies that reported the prevalence of ED risk among medical students and were published in English peer-reviewed journals between 1982 and 2017 were included. Information about study characteristics and the prevalence of ED risk were extracted by four investigators. Each article was reviewed independently by at least two investigators. Estimates were pooled using random-effects meta-analysis using the DerSimonian-Laird method. The main outcome of interest was the prevalence of ED risk in medical students. RESULTS: The prevalence of ED risk among medical students was extracted from nineteen cross-sectional studies across nine countries (total participants n = 5722). The overall pooled prevalence rate of ED risk was 10.4% (497/5722 students, 95% CI 7.8-13.0%), with statistically significant evidence between-study heterogeneity (Q = 295, τ2 = 0.003, I2 = 94.0%, P < 0.001). Prevalence estimates between studies ranged from 2.2 to 29.1%. CONCLUSION: In this systematic review and meta-analysis, the summary prevalence of ED risk among medical students was 10.4%. Further research is needed to identify and prevent ED in this population. Studies are also needed to investigate concurrent pathologies associated with ED risk. LEVEL OF EVIDENCE: Level I, systematic review and meta-analysis.

In situ characterization of stem cells-like biomarkers in meningiomas.

BACKGROUND: Meningioma cancer stem cells (MCSCs) contribute to tumor aggressiveness and drug resistance. Successful therapies developed for inoperable, recurrent, or metastatic tumors must target these cells and restrict their contribution to tumor progression. Unfortunately, the identity of MCSCs remains elusive, and MSCSs' in situ spatial distribution, heterogeneity, and relationship with tumor grade, remain unclear. METHODS: Seven tumors classified as grade II or grade III, including one case of metastatic grade III, and eight grade I meningioma tumors, were analyzed for combinations of ten stem cell (SC)-related markers using immunofluorescence of consecutive sections. The correlation of expression for all markers were investigated. Three dimensional spatial distribution of markers were qualitatively analyzed using a grid, designed as a repository of information for positive staining. All statistical analyses were completed using Statistical Analysis Software Package. RESULTS: The patterns of expression for SC-related markers were determined in the context of two dimensional distribution and cellular features. All markers could be detected in all tumors, however, Frizzled 9 and GFAP had differential expression in grade II/III compared with grade I meningioma tissues. Correlation analysis showed significant relationships between the expression of GFAP and CD133 as well as SSEA4 and Vimentin. Data from three dimensional analysis showed a complex distribution of SC markers, with increased gene hetero-expression being associated with grade II/III tumors. Sub regions that showed multiple co-staining of markers including CD133, Frizzled 9, GFAP, Vimentin, and SSEA4, but not necessarily the proliferation marker Ki67, were highly associated with grade II/III meningiomas. CONCLUSION: The distribution and level of expression of CSCs markers in meningiomas are variable and show hetero-expression patterns that have a complex spatial nature, particularly in grade II/III meningiomas. Thus, results strongly support the notion of heterogeneous populations of CSCs, even in grade I meningiomas, and call for the use of multiple markers for the accurate identification of individual CSC subgroups. Such identification will lead to practical clinical diagnostic protocols that can quantitate CSCs, predict tumor recurrence, assist in guiding treatment selection for inoperable tumors, and improve follow up of therapy.

Unintended Effects of Residential Energy Storage on Emissions from the Electric Power System.

In many jurisdictions, policy-makers are seeking to decentralize the electric power system while also promoting deep reductions in the emission of greenhouse gases (GHG). We examine the potential roles for residential energy storage (RES), a technology thought to be at the epicenter of these twin revolutions. We model the impact of grid-connected RES operation on electricity costs and GHG emissions for households in 16 of the largest U.S. utility service territories under 3 plausible operational modes. Regardless of operation mode, RES mostly increases emissions when users seek to minimize their electricity cost. When operated with the goal of minimizing emissions, RES can reduce average household emissions by 2.2-6.4%, implying a cost equivalent of $180 to $5160 per metric ton of carbon dioxide avoided. While RES is costly compared with many other emission-control measures, tariffs that internalize the social cost of carbon would reduce emissions by 0.1-5.9% relative to cost-minimizing operation. Policy-makers should be careful about assuming that decentralization will clean the electric power system, especially if it proceeds without carbon-mindful tariff reforms.

Systematic review of health state utility values in metastatic non-small cell lung cancer with a focus on previously treated patients.

BACKGROUND: Health state utility values (HSUVs) are an important input to economic evaluations and the choice of HSUV can affect the estimate of relative cost-effectiveness between interventions. This systematic review identified utility scores for patients with metastatic non-small cell lung cancer (mNSCLC), as well as disutilities or utility decrements relevant to the experience of patients with mNSCLC, by treatment line and health state. METHODS: The MEDLINE®, Embase and Cochrane Library databases were systematically searched (September 2016) for publications describing HSUVs in mNSCLC in any treatment line. The EQ-5D website, the School of Health and Related Research Health Utilities Database (ScHARRHUD) and major pharmacoeconomic and clinical conferences in 2015-2016 were also queried. Studies in adults with previously treated mNSCLC were selected for further analysis. The information extracted included study design, description of treatment and health state, respondent details, instrument and tariff, HSUV or (dis) utility decrement estimates, quality of study, and appropriateness for use in economic evaluations. RESULTS: Of 1883 references identified, 36 publications of 34 studies were included: 19 reported EQ-5D scores; eight reported HSUVs from valuations of vignettes made by members of the public using standard gamble (SG) or time trade-off (TTO); two reported SG or TTO directly elicited from patients; two reported EQ-5D visual analogue scale scores only; one reported Assessment of Quality of Life instrument scores; one reported HSUVs for caregivers to patients with mNSCLC using the 12-item Short-Form Health Survey; and one estimated HSUVs based on expert opinion. The range of HSUVs identified for comparable health states showed how differences in study type, tariff, health state and the measures used can drive variation in HSUV estimates. CONCLUSIONS: This systematic review provides a set of published HSUVs that are relevant to the experience of adult patients previously treated for mNSCLC. Our review begins to address the challenge of identifying reliable estimates of utility values in mNSCLC that are suitable for use in economic evaluations, and also highlights how varying estimates result from differences in methodology.

Is intra-bladder pressure measurement a reliable indicator for raised intra-abdominal pressure? A prospective comparative study.

BACKGROUND: Intra-abdominal pressure (IAP) can be measured by several indirect methods; however, the urinary bladder is largely preferred. The aim of this study was to compare intra-bladder pressure (IBP) at different levels of IAPs and assess its reliability as an indirect method for IAP measurement. METHODS: We compared IBP with IAP in twenty-one patients undergoing laparoscopic cholecystectomy under general anesthesia. Measurements were recorded at increasing levels of insufflation pressures to approximately 22 mmHg. Pearson's correlation coefficient was calculated to establish the relationship between the two pressure measurements and Bland-Altman analysis was used to assess the limits of agreement between the two methods of measurements. RESULTS: The urinary bladder pressures reflected well the pressures in the abdominal cavity. Pearson correlation coefficient showed a good correlation between the two measurement techniques (r = 0.966, p < 0.0001) and Bland-Altman analysis indicated that the 95% limits of agreement between the two methods ranged from - 2.83 to 2.64. This range is accepted both clinically and according to the recommendations of the World Society of Abdominal Compartment Syndrome (WSACS). CONCLUSION: Our study showed that IBP measurement is a simple, minimally invasive method that may reliably estimates IAP in patients placed in supine position. Measurements for pressures higher than 12 mmHg may be less reliable. When applied clinically, this should alert the clinician to take safety measures to avoid abdominal compartment syndrome (ACS).

Evaluating the Cost, Safety, and Proliferation Risks of Small Floating Nuclear Reactors.

It is hard to see how our energy system can be decarbonized if the world abandons nuclear power, but equally hard to introduce the technology in nonnuclear energy states. This is especially true in countries with limited technical, institutional, and regulatory capabilities, where safety and proliferation concerns are acute. Given the need to achieve serious emissions mitigation by mid-century, and the multidecadal effort required to develop robust nuclear governance institutions, we must look to other models that might facilitate nuclear plant deployment while mitigating the technology's risks. One such deployment paradigm is the build-own-operate-return model. Because returning small land-based reactors containing spent fuel is infeasible, we evaluate the cost, safety, and proliferation risks of a system in which small modular reactors are manufactured in a factory, and then deployed to a customer nation on a floating platform. This floating small modular reactor would be owned and operated by a single entity and returned unopened to the developed state for refueling. We developed a decision model that allows for a comparison of floating and land-based alternatives considering key International Atomic Energy Agency plant-siting criteria. Abandoning onsite refueling is beneficial, and floating reactors built in a central facility can potentially reduce the risk of cost overruns and the consequences of accidents. However, if the floating platform must be built to military-grade specifications, then the cost would be much higher than a land-based system. The analysis tool presented is flexible, and can assist planners in determining the scope of risks and uncertainty associated with different deployment options.

Improving biomedical information retrieval by linear combinations of different query expansion techniques.

BACKGROUND: Biomedical literature retrieval is becoming increasingly complex, and there is a fundamental need for advanced information retrieval systems. Information Retrieval (IR) programs scour unstructured materials such as text documents in large reserves of data that are usually stored on computers. IR is related to the representation, storage, and organization of information items, as well as to access. In IR one of the main problems is to determine which documents are relevant and which are not to the user's needs. Under the current regime, users cannot precisely construct queries in an accurate way to retrieve particular pieces of data from large reserves of data. Basic information retrieval systems are producing low-quality search results. In our proposed system for this paper we present a new technique to refine Information Retrieval searches to better represent the user's information need in order to enhance the performance of information retrieval by using different query expansion techniques and apply a linear combinations between them, where the combinations was linearly between two expansion results at one time. Query expansions expand the search query, for example, by finding synonyms and reweighting original terms. They provide significantly more focused, particularized search results than do basic search queries. RESULTS: The retrieval performance is measured by some variants of MAP (Mean Average Precision) and according to our experimental results, the combination of best results of query expansion is enhanced the retrieved documents and outperforms our baseline by 21.06 %, even it outperforms a previous study by 7.12 %. CONCLUSIONS: We propose several query expansion techniques and their combinations (linearly) to make user queries more cognizable to search engines and to produce higher-quality search results.

Expert assessments of the cost of light water small modular reactors.

Analysts and decision makers frequently want estimates of the cost of technologies that have yet to be developed or deployed. Small modular reactors (SMRs), which could become part of a portfolio of carbon-free energy sources, are one such technology. Existing estimates of likely SMR costs rely on problematic top-down approaches or bottom-up assessments that are proprietary. When done properly, expert elicitations can complement these approaches. We developed detailed technical descriptions of two SMR designs and then conduced elicitation interviews in which we obtained probabilistic judgments from 16 experts who are involved in, or have access to, engineering-economic assessments of SMR projects. Here, we report estimates of the overnight cost and construction duration for five reactor-deployment scenarios that involve a large reactor and two light water SMRs. Consistent with the uncertainty introduced by past cost overruns and construction delays, median estimates of the cost of new large plants vary by more than a factor of 2.5. Expert judgments about likely SMR costs display an even wider range. Median estimates for a 45 megawatts-electric (MWe) SMR range from $4,000 to $16,300/kWe and from $3,200 to $7,100/kWe for a 225-MWe SMR. Sources of disagreement are highlighted, exposing the thought processes of experts involved with SMR design. There was consensus that SMRs could be built and brought online about 2 y faster than large reactors. Experts identify more affordable unit cost, factory fabrication, and shorter construction schedules as factors that may make light water SMRs economically viable.

Unintended consequences of curtailment cap policies on power system decarbonization.

As countries pursue power system decarbonization, a well-intentioned strategy being pursued in jurisdictions like China is the strict integration target, often in the form of a curtailment cap. The effects of these curtailment caps have not been systematically studied. Here, we evaluate the effects of these caps on the decarbonization of one provincial power system using a capacity expansion model. Results reveal that curtailment caps yield deleterious effects that do not align with the stated goals of these policies. Capping curtailment significantly increases storage capacity (+43% with a 5% curtailment cap) and reduces renewable capacity (-17%). Even with the increase in flexible storage capacity, the policy still jeopardizes power system reliability by increasing occurrences of over or under generation. It also suppresses power generation from hydropower and reduces energy storage utilization while increasing fossil fuel utilization. Capping curtailment increases economic costs (+6% with a 5% curtailment cap) and CO2 emissions (+7%).

Migrated intrauterine device: Case series report.

INTRODUCTION AND IMPORTANCE: Implantation of an intrauterine device (IUD) is a common method of contraception in Saudi Arabia. Although rare, IUD migration and colon perforation have been reported. The current report presented three cases of IUD migration into the colon and recto-uterine pouch. METHODS AND OUTCOMES: The study included a series of three cases of migrated IUDs. The first case was a 25-year-old female, Gravida 2, Para 2 + 0, at 28 week-gestation, who presented with abdominal pain with a history of IUD placement that had not been removed or imaged before. The patient submitted to the caesarian section (CS), where IUD was found in the sigmoid colon. Elective laparoscopic removal of IUD with resection and primary repair of sigmoid colon was done later. The second case was a 37-year-old female, Gravida 1, Para 1 + 0, non-pregnant hypothyroidism, and a history of IUD placement. The patient got pregnant and gave birth through CS. She was then presented with abdominal pain and requested the removal of the IUD. On colonoscopy, IUD was seen in the pouch of Douglas with no evidence of a fistulous tract. IUD was removed through laparoscopy. The third case was a 47-year-old female, Gravida 14, Para 14 + 0, with a history of previous CS presented with a missing IUD that had been inserted 20 years ago after she had five pregnancies and subsequent deliveries. On colonoscopy, IUD was embedded on the wall of the transverse colon, and through abdominal surgery, IUD was removed by cutting through the colon and primary repair was done. CLINICAL DISCUSSION: the presentation of IUD migration cases was foundto vary according to the site of migration and type of IUD.however the cases are usually present with abdominal pain. An abdominal pelvic imaging with CT in these patients are essential in diagnosis. Retrival of migrating IUDs may be done through colonoscopy, laparoscopy, and in some cases with adhesion laparotomy is the solution. CONCLUSION: Abdominal and pelvic CT scan are very important in the diagnosis and the localization of IUD. Elective colonoscopy and laparoscopy are successful management approaches for these cases.

Association between Hypertension and Atrial Fibrillation in Patients on Hemodialysis.

This study aimed to evaluate the prevalence and the association between hypertension (HTN) and atrial fibrillation (AF) in hemodialysis (HD) patients. A chart review-based, cross-sectional study was conducted on HD patients who had received HD for at least 6 months. Demographic, hemodynamic, and laboratory data were retrieved from the BestCare system, and the main outcomes were blood pressure before and after dialysis, and the presence of AF. Our sample consisted of 304 HD patients; 162 (53%) were male, and the mean age was 63 ± 18 years. Sixty-eight (20%) had AF, of whom 44 (64.7%) were male, with a mean age of 73 ± 12 years. The risk of AF increased by 0.4 [odds ratio: 1.04; 95% confidence interval (CI): 1.02-1.06; P <0.001] for every year of age. Almost the entire sample (66.45%, n = 202) was hypertensive, and those patients had a mean age of 64 ± 17 years, and nearly one-third had a body mass index in the obese category (28.7%, n = 58). In addition, with every increase in the Charlson comorbidity index score by two points, there was a 40% increased risk of developing HTN (OR: 2.47; 95% CI: 1.17-5.18; P = 0.017). The risk factors for the development of HTN and AF in HD patients were found to be increasing age for AF and female sex for HTN. The presence of HTN and diabetes increased the risk of developing AF seven-fold after HD.

A paediatric dysembryoplastic neuroepithelial tumour (DNET) with deregulated stem cell markers: a case report.

Background: Dysembryoplastic neuroepithelial tumours (DNETs) are rare, with only a few reported lethal cases. Currently, there are focused efforts by neuro-oncology professionals to reveal the molecular characterisations of individual central nervous system tumours (CNSTs). Here, we report the status of cancer stem cell (CSC) genes associated with resilience and drug resistance in a paediatric DNET, since the deregulations and variations of CSC genes may prove critical to these tumours' molecular characterisations. Case Description: Immunofluorescence, clonogenic assay and whole exome sequencing (WES) were applied to the patient's tissue and its corresponding cell line. The case is for of a 6-year-old boy with intractable epilepsy and unremarkable physical and neurological examinations. Following magnetic resonance imaging (MRI) and histopathological tests, the patient was diagnosed with DNET. The child underwent a right posterior temporoparietooccipital neuronavigation-assisted craniotomy. Several CSC markers were upregulated in situ, including the metastasis-related protein, anterior gradient 2 (AGR2; 67%), and the Wnt-signalling-related protein, frizzled class receptor 9 (FZD9; 79%). The cell line possessed a similar DNA profile as the original tissue, stained positive for the tumorigenic marker [BMI1 proto-oncogene (BMI)] and CSC markers, and displayed drug resistance. Variants identified in the tissue DNA, which are listed in the catalogue of somatic mutations in cancer (COSMIC) database for genes previously known to be necessary for the development of the embryonic brain, included variants in the cell division cycle 27 (CDC27) gene. Conclusions: we report the in situ and in vitro presence of CSCs in a paediatric DNET.

Emergency deployment of direct air capture as a response to the climate crisis.

Though highly motivated to slow the climate crisis, governments may struggle to impose costly polices on entrenched interest groups, resulting in a greater need for negative emissions. Here, we model wartime-like crash deployment of direct air capture (DAC) as a policy response to the climate crisis, calculating funding, net CO2 removal, and climate impacts. An emergency DAC program, with investment of 1.2-1.9% of global GDP annually, removes 2.2-2.3 GtCO2 yr-1 in 2050, 13-20 GtCO2 yr-1 in 2075, and 570-840 GtCO2 cumulatively over 2025-2100. Compared to a future in which policy efforts to control emissions follow current trends (SSP2-4.5), DAC substantially hastens the onset of net-zero CO2 emissions (to 2085-2095) and peak warming (to 2090-2095); yet warming still reaches 2.4-2.5 °C in 2100. Such massive CO2 removals hinge on near-term investment to boost the future capacity for upscaling. DAC is most cost-effective when using electricity sources already available today: hydropower and natural gas with renewables; fully renewable systems are more expensive because their low load factors do not allow efficient amortization of capital-intensive DAC plants.

Efficient purification of wastewater by applying mechanical force and BaCO3/TiO2 and BaTiO3/TiO2 piezocatalysts.

In typical advanced oxidation catalysis, a semiconductor should have a robust capacity to generate separated electron-hole pairs on a material's surface under irradiation of photons with energy more than the material's bandgap. However, rapid charge carrier recombination and low photon to current yield of semiconductor photocatalysts and low percentages of UV light in sunlight leads to a low level of photocatalytic efficiency for practical application. Mechanical energy is a natural energy that can be considered as a form of rich, clean and renewable energy which can be harvested by using piezoelectric materials. Here, we developed BaCO3/TiO2 and BaTiO3/TiO2 composites as mechanical harvesting materials to decontaminate pollutants. Results showed that BaCO3 has a great effect on the piezocatalytic activity of products. The control sample (sample without Ba) only degraded 11.2% of Acid Red 151 (AR151) , while the sample containing Ba degraded 96.7% of AR151. Besides, the effects of several parameters, including the natural surfactant, reaction time and temperature, calcination, and ultrasonic power and pulse on the catalytic activity of the as-prepared piezocatalysts were studied. Results showed that it is possible to degrade 99.1% of AR151 by controlling ultrasonic parameters during 2 h of mechanical energy force.

Re-exploration for bleeding after cardiac surgery: revaluation of urgency and factors promoting low rate.

BACKGROUND: Re-exploration of bleeding after cardiac surgery is associated with significant morbidity and mortality. Perioperative blood loss and rate of re-exploration are variable among centers and surgeons. OBJECTIVE: To present our experience of low rate of re-exploration based on adopting checklist for hemostasis and algorithm for management. METHODS: Retrospective analysis of medical records was conducted for 565 adult patients who underwent surgical treatment of congenital and acquired heart disease and were complicated by postoperative bleeding from Feb 2006 to May 2019. Demographics of patients, operative characteristics, perioperative risk factors, blood loss, requirements of blood transfusion, morbidity and mortality were recorded. Logistic regression was used to identify predictors of re-exploration and determinants of adverse outcome. RESULTS: Thirteen patients (1.14%) were reexplored for bleeding. An identifiable source of bleeding was found in 11 (84.6%) patients. Risk factors for re-exploration were high body mass index, high Euro SCORE, operative priority (urgent/emergent), elevated serum creatinine and low platelets count. Re-exploration was significantly associated with increased requirements of blood transfusion, adverse effects on cardiorespiratory state (low ejection fraction, increased s. lactate, and prolonged period of mechanical ventilation), longer intensive care unit stay, hospital stay, increased incidence of SWI, and higher mortality (15.4% versus 2.53% for non-reexplored patients). We managed 285 patients with severe or massive bleeding conservatively by hemostatic agents according to our protocol with no added risk of morbidity or mortality. CONCLUSION: Low rate of re-exploration for bleeding can be achieved by strict preoperative preparation, intraoperative checklist for hemostasis implemented by senior surgeons and adopting an algorithm for management.