Zebrafish is a powerful model for forward genetics. Reverse genetic approaches are limited by the time required to generate stable mutant lines. We describe a system for gene knockout that ...consistently produces null phenotypes in G0 zebrafish. Yolk injection of sets of four CRISPR/Cas9 ribonucleoprotein complexes redundantly targeting a single gene recapitulated germline-transmitted knockout phenotypes in >90% of G0 embryos for each of 8 test genes. Early embryonic (6 hpf) and stable adult phenotypes were produced. Simultaneous multi-gene knockout was feasible but associated with toxicity in some cases. To facilitate use, we generated a lookup table of four-guide sets for 21,386 zebrafish genes and validated several. Using this resource, we targeted 50 cardiomyocyte transcriptional regulators and uncovered a role of zbtb16a in cardiac development. This system provides a platform for rapid screening of genes of interest in development, physiology, and disease models in zebrafish.
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•Redundant targeting of single genes generates nearly complete gene disruption•Effects are early and durable, complementing morpholino-based approaches•A genome-scale guide set provides a resource to aid automated experimental design•A transcription factor screen uncovers a role for zbtb16a in heart development
Wu et al. describe a pipeline for CRISPR/Cas9 genetic screening with optimized, redundant gene targeting to produce penetrant gene disruption in zebrafish. The authors evaluate this system on several genes and apply this strategy to 50 empirically identified zebrafish cardiomyocyte transcription factors, uncovering a role for zbtb16a in cardiac development.
Tourism efficiency has become an important role in promoting tourism competitiveness and driving sustainable development. It is particularly important to identify and agnalyze the factors and ...mechanisms that affect efficiency. This paper firstly evaluates the tourism efficiency of 11 coastal provinces regions in China from 2010 to 2020 by using the DEA-BBC model that includes undesirable outputs. After that, it investigates the internal driving mechanism of the efficiency change through the Malmquist index and its decomposition. Finally, it analyzes the external influencing elements of tourist efficiency by the Tobit model. The results show that: (1) Although the average value of the tourism efficiency was changed from 0.727 to 0.707, it does not achieve the target. Its trend shows fluctuating from 2010-2020, which indicates that the tourism efficiency of most provincial regions is not optimal. The main factor that restricts tourism efficiency is scale efficiency. (2) By analyzing the dynamic trend, it is found that the average increase of technical efficiency is 14.0%, the average increase of technical change is 9.5%, and the average increase of MI index is 25.4%. It indicates that the overall tourism efficiency of 11 coastal provinces region in China is on the rise. (3) The spatial difference of tourism efficiency is significant, but there is no obvious spatial correlation. (4) The influencing factors of tourism efficiency are consumer demand, industrial structure, labor force and urbanization.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract The precise definition of the lower mass limit of red supergiant stars (RSGs) is an open question in astrophysics and does not attract much attention. Here, we assemble a spectroscopic ...evolved cool star sample with 6602 targets, including RSGs, asymptotic giant branch stars, and red giant branch stars, in the Large Magellanic Cloud based on Gaia DR3 and Sloan Digital Sky Survey IV/APOGEE-2. The reference spectrum of each stellar population is built according to the quantile range of relative intensity (1% ∼ 99%). Five different methods, e.g., χ 2 , cosine similarity, machine learning (ML), equivalent width, and line ratio, are used in order to separate different stellar populations. ML and χ 2 provide the best and relatively consistent prediction of a certain population. The derived lower limit of the RSG population is able to reach the K s -band tip of the red giant branch ( K s ≈12.0 mag), indicating a luminosity as low as about 10 3.5 L ⊙ , which corresponds to a stellar radius of only about 100 R ⊙ . Given the mass–luminosity relation of L / L ⊙ = f ( M / M ⊙ ) 3 with f ≈ 15.5 ± 3 and taking into account the mass loss of faint RSGs up to now, the minimal initial mass of the RSG population would be about 6.1 ± 0.4 M ⊙ , which is much lower than the traditional threshold of 8 M ⊙ for the massive stars. This is the first spectroscopic evidence, indicating that the lower mass limit of the RSG population is around 6 M ⊙ . However, the destinies of such faint RSGs are still elusive and may have a large impact on stellar evolutionary and supernova models.
Diabetic retinopathy (DR) was identified as a leading cause of blindness and vision impairment in 2020. In addition to vasculopathy, DR has been found to involve retinal neurons, including amacrine ...cells and retinal ganglion cells. Despite possessing features that are susceptible to diabetic conditions, photoreceptor cells have received relatively little attention with respect to the development of DR. Until recently, studies have suggested that photoreceptors secret proinflammatory molecules and produce reactive oxygen species that contribute to the development of DR. However, the effect of hyperglycemia on photoreceptors and its underlying mechanism remains elusive. In this study, the direct effect of high glucose on photoreceptor cells was investigated using a 661w photoreceptor-like cell line. A data-independent sequential window acquisition of all theoretical mass spectra (SWATH)-based proteomic approach was employed to study changes induced by high glucose in the proteomic profile of the cells. The results indicated that high glucose induced a significant increase in apoptosis and ROS levels in the 661w cells, with mitochondrial dysfunction among the major affected canonical pathways. The involvement of mitochondrial dysfunction was further supported by increased mitochondrial fission and reduced mitochondrial bioenergetics. Collectively, these findings provide a biological basis for a possible role of photoreceptors in the pathogenesis of DR.
IntroductionBig data technologies have been talked up in the fields of science and medicine. The V-criteria (volume, variety, velocity and veracity, etc) for defining big data have been well-known ...and even quoted in most research articles; however, big data research into public health is often misrepresented due to certain common misconceptions. Such misrepresentations and misconceptions would mislead study designs, research findings and healthcare decision-making. This study aims to identify the V-eligibility of big data studies and their technologies applied to environmental health and health services research that explicitly claim to be big data studies.Methods and analysisOur protocol follows Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P). Scoping review and/or systematic review will be conducted. The results will be reported using PRISMA for Scoping Reviews (PRISMA-ScR), or PRISMA 2020 and Synthesis Without Meta-analysis guideline. Web of Science, PubMed, Medline and ProQuest Central will be searched for the articles from the database inception to 2021. Two reviewers will independently select eligible studies and extract specified data. The numeric data will be analysed with R statistical software. The text data will be analysed with NVivo wherever applicable.Ethics and disseminationThis study will review the literature of big data research related to both environmental health and health services. Ethics approval is not required as all data are publicly available and involves confidential personal data. We will disseminate our findings in a peer-reviewed journal.PROSPERO registration numberCRD42021202306.
UK and European guidelines recommend consideration of a self-expandable metallic stent (SEMS) as an alternative to emergency surgery in left-sided colonic obstruction. However, there is no clear ...consensus on stenting owing to concern for complications and long-term outcomes. Our study is the first to explore SEMS provision across England.
All colorectal surgery department leads in England were contacted in 2018 and invited to complete an objective multiple choice questionnaire pertaining to service provision of colorectal stenting (including referrals, time, location and specialty).
Of 182 hospitals contacted, 79 responded (24 teaching hospitals, 55 district general hospitals). All hospitals considered stenting, with 92% performing stenting and the remainder referring. The majority (93%) performed fewer than four stenting procedures per month. Most (96%) stented during normal weekday hours, with only 25% stenting out of hours and 23% at weekends. Compared with district general hospitals, a higher proportion of teaching hospitals stented out of hours and at weekends. Stenting was performed in the radiology department (64%), the endoscopy department (44%) and operating theatres (15%), by surgeons (63%), radiologists (60%) and gastroenterologists (48%). A radiologist was present in 66% of cases. Of 14 hospitals that received referrals, 3 had a protocol, 3 returned patients the same day and 4 returned patients for management in the event of failure.
All responding hospitals in England consider the use of SEMS in colonic obstruction. Nevertheless, there is great variation in stenting practices, and challenges in terms of access and expertise. Centralisation and regional referral networks may help maximise availability and expertise but more work is needed to support this.
Sustained activation of N-methyl-d-aspartate (NMDA) -type glutamate receptors leads to excitotoxic neuronal death in stroke, brain trauma, and neurodegenerative disorders. Superoxide production by ...NADPH oxidase is a requisite event in the process leading from NMDA receptor activation to excitotoxic death. NADPH oxidase generates intracellular H ⁺ along with extracellular superoxide, and the intracellular H ⁺ must be released or neutralized to permit continued NADPH oxidase function. In cultured neurons, NMDA-induced superoxide production and neuronal death were prevented by intracellular acidification by as little as 0.2 pH units, induced by either lowered medium pH or by inhibiting Na ⁺/H ⁺ exchange. In mouse brain, superoxide production induced by NMDA injections or ischemia–reperfusion was likewise prevented by inhibiting Na ⁺/H ⁺ exchange and by reduced expression of the Na ⁺/H ⁺ exchanger-1 (NHE1). Neuronal intracellular pH and neuronal Na ⁺/H ⁺ exchange are thus potent regulators of excitotoxic superoxide production. These findings identify a mechanism by which cell metabolism can influence coupling between NMDA receptor activation and superoxide production.
An efficient surface defect passivation is observed by reacting clean Si in a dilute hydrogen sulfide-argon gas mixture (< 5% H2S in Ar) for both n-type and p-type Si wafers with planar and textured ...surfaces. Surface recombination velocities of 1.5 and 8 cm/s are achieved on n-type and p-type Si wafers, respectively, at an optimum reaction temperature of 550oC that are comparable to the best surface passivation quality used in high efficiency Si solar cells. Surface chemical analysis using x-ray photoelectron spectroscopy shows that sulfur is primarily bonded in a sulfide environment, and synchrotron-based soft x-ray emission spectroscopy of the adsorbed sulfur atoms suggests the formation of S-Si bonds. Furthermore, the sulfur surface passivation layer is unstable in air, attributed to surface oxide formation and a simultaneous decrease of sulfide bonds. However, the passivation can be stabilized by a low-temperature (300oC) deposited amorphous silicon nitride (a-Si:NX:H) capping layer.
Aims
The use of microbial fuel cells (MFC) to treat winery wastewater is promising; however, an initial acidic pH, fluctuating chemical oxygen demand (COD) levels and a lack of natural buffering in ...these wastewaters make providing a suitable buffer system at an ideal buffer to COD ratio.
Methods and Results
A lab scale MFC was designed, inoculated with anaerobic winery sludge and fed with synthetic winery wastewater. It was observed that at pH 6·5, the MFC performed best, the maximum output voltage was 0·63 ± 0·01 V for 60 ± 3 h, and the COD removal efficiency reached 77 ± 7%. The electrogens were affected by pH much more than the bulk COD degrading organisms. Fluorescent in situ hybridization suggested Betaproteobacteria played a significant role in electron transfer.
Conclusions
A ratio of 1 mmol l−1 phosphate buffer to 100 mg l−1 COD was ideal to maintain a stable pH for MFCs treating synthetic winery wastewater.
Significance and Impact of the Study
The results find the narrow pH tolerance for MFCs treating winery wastewater and demonstrate the significance of pH and buffer to COD ratio for steady performance of MFCs.
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