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Climate change is a defining challenge of the 21st century, and this decade is a critical time for action to mitigate the worst effects on human populations and ecosystems. Plant science can play an important role in developing crops with enhanced resilience to harsh conditions (e.g. heat, drought, salt stress, flooding, disease outbreaks) and engineering efficient carbon-capturing and carbon-sequestering plants. Here, we present examples of research being conducted in these areas and discuss challenges and open questions as a call to action for the plant science community.

Epidemiological evidence suggests that kava (Piper methysticum Forst) drinks may reduce the risk of cancer in South Pacific Island smokers. However, little is known about the anti-carcinogenic effects of kava on tobacco smoking-related bladder cancer and its underlying mechanisms. Here we show that dietary feeding of kawain (a major active component in kava root extracts) to mice either before or after hydroxy butyl(butyl) nitrosamine (OH-BBN) carcinogen exposure slows down urinary bladder carcinogenesis and prolongs the survival of the OH-BBN-exposed mice. OH-BBN-induced bladder tumors exhibit significantly increased expression of lysine-specific demethylase 1 (LSD1), accompanied by decreased levels of H3K4 mono-methylation compared to normal bladder epithelium, whereas dietary kawain reverses the effects of OH-BBN on H3K4 mono-methylation. Human bladder cancer tumor tissues at different pathological grades also show significantly increased expression of LSD1 and decreased levels of H3K4 mono-methylation compared to normal urothelium. In addition, kava root extracts and the kavalactones kawain and methysticin all increase the levels of H3K4 mono- and di-methylation, leading to inhibitory effects on cell migration. Taken together, our results suggest that modification of histone lysine methylation may represent a new approach to bladder cancer prevention and treatment and that kavalactones may be promising agents for bladder cancer interception in both current and former smokers.

The FaceBase Consortium was established by the National Institute of Dental and Craniofacial Research in 2009 as a 'big data' resource for the craniofacial research community. Over the past decade, researchers have deposited hundreds of annotated and curated datasets on both normal and disordered craniofacial development in FaceBase, all freely available to the research community on the FaceBase Hub website. The Hub has developed numerous visualization and analysis tools designed to promote integration of multidisciplinary data while remaining dedicated to the FAIR principles of data management (findability, accessibility, interoperability and reusability) and providing a faceted search infrastructure for locating desired data efficiently. Summaries of the datasets generated by the FaceBase projects from 2014 to 2019 are provided here. FaceBase 3 now welcomes contributions of data on craniofacial and dental development in humans, model organisms and cell lines. Collectively, the FaceBase Consortium, along with other NIH-supported data resources, provide a continuously growing, dynamic and current resource for the scientific community while improving data reproducibility and fulfilling data sharing requirements.

A predator's ability to capture prey depends critically on how it coordinates its approach in response to a prey's motion. Flying insects, bats and raptors are capable of capturing prey with a strategy known as parallel navigation, which allows a predator to move directly towards the anticipated point of interception. It is unclear if predators using other modes of locomotion are employing this strategy when pursuing evasive prey. Using kinematic measurements and mathematical modelling, we tested whether bluefish ( Pomatomus saltatrix) pursue prey fish ( Fundulus heteroclitus) with parallel navigation. We found that the directional changes of bluefish were not consistent with this strategy, but rather were predicted by a strategy known as deviated pursuit. Although deviated pursuit requires few sensory cues and relatively modest motor coordination, a comparison of mathematical models suggested negligible differences in path length from parallel navigation, largely owing to the acceleration exhibited by bluefish near the end of a pursuit. Therefore, the strategy of bluefish is unlike flying predators, but offers comparable performance with potentially more robust control that may be well suited to the visual system and habitat of fishes. These findings offer a foundation for understanding the sensing and locomotor control of predatory fishes.

Numerous studies have shown that learning is enhanced when students show interest in the subject matter. However, educators continue to grapple with the challenges, or simply do not recognize their potential roles, in the development of students' academic interest and interest in learning in general. This conceptual paper is written under the auspices of the interest-driven creator (IDC) initiative, a theoretical synthesis effort carried out by a group of educational researchers in Asia. The intention is to co-construct a holistic developmental/design framework to guide the students in fostering their learning interests, capabilities in creation, and learning habits--the three anchored concepts of IDC theory. This paper focuses on delineating a three-component "interest loop" to guide the design of a coherent learning process that encompasses a series of learning tasks. The three components are triggering interest, immersing interest, and extending interest. Underpinned by the rich literature on interest development, we will propose suitable design strategies for each of the three components, namely, curiosity, flow, and meaningfulness, respectively. We will then explicate their respective design considerations/principles to maximize the intended effects.

Interest-driven creator (IDC) theory is a design theory that intends to inform the design of future education in Asia. It consists of three anchored concepts, namely, interest, creation, and habit. This paper presents the third anchored concept habit as well as the habit loop. IDC theory assumes that learners, when driven by interest, can be engaged in knowledge creation. Furthermore, by repeating such process in their daily learning routines, learners will form interest-driven creation habits. The habit loop, the process of building such a habit, consists of three component concepts--cuing environment, routine, and harmony. The cuing environment is a habit trigger that tells the students' brain to get prepared and go into an automatic mode, letting a learning behavior unfold. Routine refers to the behavioral patterns the students repeat most often, literally etched into their neural pathways. Harmony refers to the affective outcome of the routine activity as well as the integration or stabilization of habits; that is, through the routine behavior and action, students may feel that their needs get fulfilled, feel satisfied, and experience inner peace. It is our hope that such habitual behavior of creating knowledge can be sustained so long that students ultimately become lifelong interest-driven creators. This paper focuses on the description of the three components of the habit loop and discusses how these components are related to the interest loop and the creation loop in supporting learners in developing their interest-driven creation capability.

The Calvin-Benson-Bassham (CBB) cycle is presumably evolved for optimal synthesis of C3 sugars, but not for the production of C2 metabolite acetyl-CoA. The carbon loss in producing acetyl-CoA from decarboxylation of C3 sugar limits the maximum carbon yield of photosynthesis. Here we design a synthetic malyl-CoA-glycerate (MCG) pathway to augment the CBB cycle for efficient acetyl-CoA synthesis. This pathway converts a C3 metabolite to two acetyl-CoA by fixation of one additional CO2 equivalent, or assimilates glyoxylate, a photorespiration intermediate, to produce acetyl-CoA without net carbon loss. We first functionally demonstrate the design of the MCG pathway in vitro and in Escherichia coli. We then implement the pathway in a photosynthetic organism Synechococcus elongates PCC7942, and show that it increases the intracellular acetyl-CoA pool and enhances bicarbonate assimilation by roughly 2-fold. This work provides a strategy to improve carbon fixation efficiency in photosynthetic organisms.

Purpose: The majority of bladder cancer patients present with localized disease and are managed by transurethral resection. However, the high rate of recurrence necessitates lifetime cystoscopic surveillance. Developing a sensitive and specific urine-based test would significantly improve bladder cancer screening, detection, and surveillance.Experimental Design: RNA-seq was used for biomarker discovery to directly assess the gene expression profile of exfoliated urothelial cells in urine derived from bladder cancer patients (n = 13) and controls (n = 10). Eight bladder cancer specific and 3 reference genes identified by RNA-seq were quantitated by qPCR in a training cohort of 102 urine samples. A diagnostic model based on the training cohort was constructed using multiple logistic regression. The model was further validated in an independent cohort of 101 urines.Results: A total of 418 genes were found to be differentially expressed between bladder cancer and controls. Validation of a subset of these genes was used to construct an equation for computing a probability of bladder cancer score (PBC) based on expression of three markers (ROBO1, WNT5A, and CDC42BPB). Setting PBC = 0.45 as the cutoff for a positive test, urine testing using the three-marker panel had overall 88% sensitivity and 92% specificity in the training cohort. The accuracy of the three-marker panel in the independent validation cohort yielded an AUC of 0.87 and overall 83% sensitivity and 89% specificity.Conclusions: Urine-based molecular diagnostics using this three-marker signature could provide a valuable adjunct to cystoscopy and may lead to a reduction of unnecessary procedures for bladder cancer diagnosis. Clin Cancer Res; 23(14); 3700-10. ©2017 AACR.

ObjectiveAlthough fluorescence imaging is being applied to a wide range of cancers, it remains unclear which disease populations will benefit greatest. Therefore, we review the potential of this technology to improve outcomes in surgical oncology with attention to the various surgical procedures while exploring trial endpoints that may be optimal for each tumor type.BackgroundFor many tumors, primary treatment is surgical resection with negative margins, which corresponds to improved survival and a reduction in subsequent adjuvant therapies. Despite unfavorable effect on patient outcomes, margin positivity rate has not changed significantly over the years. Thus, patients often experience high rates of re-excision, radical resections, and overtreatment. However, fluorescence-guided surgery (FGS) has brought forth new light by allowing detection of subclinical disease not readily visible with the naked eye.MethodsWe performed a systematic review of clinicatrials.gov using search terms "fluorescence," "image-guided surgery," and "near-infrared imaging" to identify trials utilizing FGS for those received on or before May 2016.Inclusion criteriafluorescence surgery for tumor debulking, wide local excision, whole-organ resection, and peritoneal metastases.Exclusion criteriafluorescence in situ hybridization, fluorescence imaging for lymph node mapping, nonmalignant lesions, nonsurgical purposes, or image guidance without fluorescence.ResultsInitial search produced 844 entries, which was narrowed down to 68 trials. Review of literature and clinical trials identified 3 primary resection methods for utilizing FGS: (1) debulking, (2) wide local excision, and (3) whole organ excision.ConclusionsThe use of FGS as a surgical guide enhancement has the potential to improve survival and quality of life outcomes for patients. And, as the number of clinical trials rise each year, it is apparent that FGS has great potential for a broad range of clinical applications.

High titer 1-butanol production in Escherichia coli has previously been achieved by overexpression of a modified clostridial 1-butanol production pathway and subsequent deletion of native fermentation pathways. This strategy couples growth with production as 1-butanol pathway offers the only available terminal electron acceptors required for growth in anaerobic conditions. With further inclusion of other well-established metabolic engineering principles, a titer of 15g/L has been obtained. In achieving this titer, many currently existing strategies have been exhausted, and 1-butanol toxicity level has been surpassed. Therefore, continued engineering of the host strain for increased production requires implementation of alternative strategies that seek to identify non-obvious targets for improvement. In this study, a metabolomics-driven approach was used to reveal a CoA imbalance resulting from a pta deletion that caused undesirable accumulation of pyruvate, butanoate, and other CoA-derived compounds. Using metabolomics, the reduction of butanoyl-CoA to butanal catalyzed by alcohol dehydrogenase AdhE2 was determined as a rate-limiting step. Fine-tuning of this activity and subsequent release of free CoA restored the CoA balance that resulted in a titer of 18.3g/L upon improvement of total free CoA levels using cysteine supplementation. By enhancing AdhE2 activity, carbon flux was directed towards 1-butanol production and undesirable accumulation of pyruvate and butanoate was diminished. This study represents the initial report describing the improvement of 1-butanol production in E. coli by resolving CoA imbalance, which was based on metabolome analysis and rational metabolic engineering strategies.

Keto acid decarboxylase (Kdc) is a key enzyme in producing keto acid derived higher alcohols, like isobutanol. The most active Kdc's are found in mesophiles; the only reported Kdc activity in thermophiles is 2 orders of magnitude less active. Therefore, the thermostability of mesophilic Kdc limits isobutanol production temperature. Here, we report development of a thermostable 2-ketoisovalerate decarboxylase (Kivd) with 10.5-fold increased residual activity after 1h preincubation at 60 °C. Starting with mesophilic Lactococcus lactis Kivd, a library was generated using random mutagenesis and approximately 8,000 independent variants were screened. The top single-mutation variants were recombined. To further improve thermostability, 16 designs built using Rosetta Comparative Modeling were screened and the most active was recombined to form our best variant, LLM4. Compared to wild-type Kivd, a 13 °C increase in melting temperature and over 4-fold increase in half-life at 60 °C were observed. LLM4 will be useful for keto acid derived alcohol production in lignocellulosic thermophiles.

The interest-driven creator (IDC) theory is being developed as a group endeavor by Asian researchers to articulate a holistic learning design theory for future education in Asia. The theory hypothesizes that students, driven by "interest", can be engaged in the "creation" of knowledge (generating ideas and artifacts). By repeating this creation process in their daily learning routines, they will excel in learning performance, develop twenty-first-century competencies, and form creation "habits". We hope that with such practices in education, our future generations will ultimately become lifelong interest-driven creators. In IDC Theory, there are three "anchored" concepts, namely, interest, creation, and habit. Each anchored concept comprises three "component" concepts which form a "concept loop". For example, the creation loop consists of three component concepts--"imitating", "combining", and "staging". Imitating is concerned with taking in (or inputting) an abundant amount of existing knowledge from the outside world to form one's background knowledge. Combining refers to delivering (or outputting) new ideas or artifacts prolifically by synthesizing existing information encountered in the world and thoughts arising from the students' background knowledge. Staging relates to frequently demonstrating the generated ideas or artifacts to the relevant communities and receiving feedback from these communities to improve the novelty and value of the demonstrated outcomes while gaining social recognition and nurturing positive social emotions. This paper focuses on describing the three components of the creation loop. We provide three case studies to illustrate the creation loop at work, as well as how it intertwines with both the interest and habit loops in supporting students to develop their creation capabilities. In presenting this iteration of the creation concept, an anchored concept in IDC theory, we acknowledge the roles played of imitation, combination, and staging in different learning and education contexts--indeed, there are multiple theories that inform and intersect with it.

Conventional teacher-led instruction remains dominant in most elementary mathematics classrooms in Taiwan. Under such instruction, the teacher can rarely take care of all students. Many students may then continue to fall behind the standard of mathematics achievement and lose their interest in mathematics; they eventually give up on learning mathematics. In fact, students in Taiwan generally have lower interest in learning mathematics compared to many other regions/countries. Thus, how to enhance students' mathematics achievement and interest are two major problems, especially for those low-achieving students. This paper describes how we designed a game-based learning environment, called "Math-Island," by incorporating the mechanisms of a construction management game into the knowledge map of the elementary mathematics curriculum. We also report an experiment conducted with 215 elementary students for 2 years, from grade 2 to grade 3. In this experiment, in addition to teacher-led instruction in the classroom, students were directed to learn with Math-Island by using their own tablets at school and at home. As a result of this experiment, we found that there is an increase in students' mathematics achievement, especially in the calculation and word problems. Moreover, the achievements of low-achieving students in the experimental school outperformed the low-achieving students in the control school (a control group in another school) in word problems. Moreover, both the low-achieving students and the high-achieving students in the experimental school maintained a rather high level of interest in mathematics and in the system.

Methanol utilization by methylotrophic or non-methylotrophic organisms is the first step toward methanol bioconversion to higher carbon-chain chemicals. Methanol oxidation using NAD-dependent methanol dehydrogenase (Mdh) is of particular interest because it uses NAD(+) as the electron carrier. To our knowledge, only a limited number of NAD-dependent Mdhs have been reported. The most studied is the Bacillus methanolicus Mdh, which exhibits low enzyme specificity to methanol and is dependent on an endogenous activator protein (ACT). In this work, we characterized and engineered a group III NAD-dependent alcohol dehydrogenase (Mdh2) from Cupriavidus necator N-1 (previously designated as Ralstonia eutropha). This enzyme is the first NAD-dependent Mdh characterized from a Gram-negative, mesophilic, non-methylotrophic organism with a significant activity towards methanol. Interestingly, unlike previously reported Mdhs, Mdh2 does not require activation by known activators such as B. methanolicus ACT and Escherichia coli Nudix hydrolase NudF, or putative native C. necator activators in the Nudix family under mesophilic conditions. This enzyme exhibited higher or comparable activity and affinity toward methanol relative to the B. methanolicus Mdh with or without ACT in a wide range of temperatures. Furthermore, using directed molecular evolution, we engineered a variant (CT4-1) of Mdh2 that showed a 6-fold higher K cat/K m for methanol and 10-fold lower K cat/K m for n-butanol. Thus, CT4-1 represents an NAD-dependent Mdh with much improved catalytic efficiency and specificity toward methanol compared with the existing NAD-dependent Mdhs with or without ACT activation.

Navigation with fluorescence guidance has emerged in the last decade as a promising strategy to improve the efficacy of oncologic surgery. To achieve routine clinical use, the onus is on the surgical community to objectively assess the value of this technique. This assessment may facilitate both Food and Drug Administration approval of new optical imaging agents and reimbursement for the imaging procedures. It is critical to characterize fluorescence-guided procedural benefits over existing practices and to elucidate both the costs and the safety risks. This report is the result of a meeting of the International Society of Image Guided Surgery (www.isigs.org) on February 6, 2015, in Miami, Florida, and reflects a consensus of the participants' opinions. Our objective was to critically evaluate the imaging platform technology and optical imaging agents and to make recommendations for successful clinical trial development of this highly promising approach in oncologic surgery.