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We have compared the decay rates of KL and KS toΠ+ Π- Π0Π0 final states using a subset of the data from the KTeV experiment (E832) at Fermilab. We find that the direct-CP-violation parameter Re (μ’/μ) is equal to [28.0±3.0(stat)±2.8(syst)]×10-4. This result definitively establishes the existence of CP violation in a decay process. © 1999 The American Physical Society.

We have compared the decay rates of KL and KS toΠ+ Π- Π0Π0 final states using a subset of the data from the KTeV experiment (E832) at Fermilab. We find that the direct-CP-violation parameter Re (μ’/μ) is equal to [28.0±3.0(stat)±2.8(syst)]×10-4. This result definitively establishes the existence of CP violation in a decay process. © 1999 The American Physical Society.

The genus Magicicada (Hemiptera: Cicadidae) includes the periodical cicadas of Eastern North America. Spending the majority of their long lives underground, the adult cicadas emerge every 13 or 17 years to spend 4-6 weeks as adult to mate. We present the whole genome sequences of two species of 17-year cicadas, Magicicada septendecim and Magicicada septendecula . The reads were assembled by a de novo method followed by alignments to related species. Annotation was performed by GeneMark-ES. The raw and assembled data is available via NCBI Short Read Archive and Assembly databases.

Objective: The aim of this study was to analyze the wound complication (WC) rate and to determine the risk factors for WC in patients with soft tissue sarcoma treated with preoperative radiotherapy followed by surgical resection., Methods: Using the database of Oxford University Hospital (OUH) we retrospectively studied 126 cases of soft tissue sarcomas treated with preoperative radiotherapy and surgery between 2007 and 2021. WC were defined as minor wound complication (MiWC) not requiring surgical intervention or major wound complication (MaWC) if they received a secondary surgical intervention. Univariate and multiple regression analyses were performed using frequency of WC and MaWC as a dependent variable., Results: The incidence of WC and MaWC was 43.7% (55/126) and 19% (24/126). Age (OR:1.03, 95%CI: 1.00-1.06, p = 0.016), tumor size (OR:1.11, 95%CI:1.01-1.21, p = 0.027) and tumor site namely proximal lower limb vs upper limb (OR:10.87, 95%CI 1.15-103.03, p = 0.038) were risk factors on multivariate analysis. In nested case control analysis, the incidence of MaWC was 43.6% (24/55), the mean recovery time is 143 days in patients with MaWC. Smoking increases the risk for MaWC (OR:8.32, 95%CI:1.36-49.99, p = 0.022). The time interval between surgery and wound complication reduces the risk for MaWC (OR:0.91, 95%CI:0.84-0.99, p = 0.028) in multivariate analysis., Conclusions: Age, tumor site and size are risk factors for WC requiring preoperative radiotherapy. Smoking and the time interval between surgery and wound complication are risk factors for MaWC as compared with MiWC. MaWC rate (19%) are comparable to those in postoperative radiotherapy and surgery alone., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 Published by Elsevier Ltd.)

Introduction: Sarcomas of the head and neck are neoplasms arising from the embryonic mesenchyme. They are rare and heterogeneous in nature and are associated with significant morbidity and mortality. This study evaluates patients referred to the Oxford Sarcoma Service, a tertiary referral centre., Methods: Patients discussed over a three-year period were included. Medical records were analysed using the electronic patient record database. Data were acquired on a range of domains, including: demographics, histopathology, treatment modality, recurrence, mortality, survival, etc., Results: Thirty-two eligible patients, 21 male and 11 female, were identified with a mean age of 58 years; 26 out of 32 patients had high-grade sarcomas. The commonest histological subtype was chondrosarcoma (8/32). Twenty-two underwent planned multidisciplinary team surgical resection after biopsy and staging: negative margins were noted in 9, with close and involved margins in 5 and 8, respectively. Local recurrence was noted in 13 and 6 had metastatic disease out of the 32 eligible patients. Mortality was noted in 10 out of 32 patients. Mean survival was 69.5 months. Five-year overall survival was 64%. Surgery demonstrated statistically significant improvement in survival ( p =0.0095). There were no significant differences in survival, recurrence or marginal status between methods of adjuvant or neoadjuvant therapy., Conclusion: Outcomes of head and neck sarcomas are inferior compared with other types of sarcoma. The nature of the complex surrounding anatomy presents unique challenges in surgical management. This in turn affects rates of local recurrence and prognosis. Therefore, it is critical that they are managed in tertiary, specialist centres with a multidisciplinary approach.

Background: Although hatching is perhaps the most abrupt and profound metabolic challenge that a chicken must undergo; there have been no attempts to functionally map the metabolic pathways induced in liver during the embryo-to-hatchling transition. Furthermore, we know very little about the metabolic and regulatory factors that regulate lipid metabolism in late embryos or newly-hatched chicks. In the present study, we examined hepatic transcriptomes of 12 embryos and 12 hatchling chicks during the peri-hatch period-or the metabolic switch from chorioallantoic to pulmonary respiration., Results: Initial hierarchical clustering revealed two distinct, albeit opposing, patterns of hepatic gene expression. Cluster A genes are largely lipolytic and highly expressed in embryos. While, Cluster B genes are lipogenic/thermogenic and mainly controlled by the lipogenic transcription factor THRSPA. Using pairwise comparisons of embryo and hatchling ages, we found 1272 genes that were differentially expressed between embryos and hatchling chicks, including 24 transcription factors and 284 genes that regulate lipid metabolism. The three most differentially-expressed transcripts found in liver of embryos were MOGAT1, DIO3 and PDK4, whereas THRSPA, FASN and DIO2 were highest in hatchlings. An unusual finding was the "ectopic" and extremely high differentially expression of seven feather keratin transcripts in liver of 16 day embryos, which coincides with engorgement of liver with yolk lipids. Gene interaction networks show several transcription factors, transcriptional co-activators/co-inhibitors and their downstream genes that exert a 'ying-yang' action on lipid metabolism during the embryo-to-hatching transition. These upstream regulators include ligand-activated transcription factors, sirtuins and Kruppel-like factors., Conclusions: Our genome-wide transcriptional analysis has greatly expanded the hepatic repertoire of regulatory and metabolic genes involved in the embryo-to-hatchling transition. New knowledge was gained on interactive transcriptional networks and metabolic pathways that enable the abrupt switch from ectothermy (embryo) to endothermy (hatchling) in the chicken. Several transcription factors and their coactivators/co-inhibitors appear to exert opposing actions on lipid metabolism, leading to the predominance of lipolysis in embryos and lipogenesis in hatchlings. Our analysis of hepatic transcriptomes has enabled discovery of opposing, interconnected and interdependent transcriptional regulators that provide precise ying-yang or homeorhetic regulation of lipid metabolism during the critical embryo-to-hatchling transition.

Background: A strain of Leghorn chickens (rd/rd), unable to produce a functional riboflavin-binding protein, lays riboflavin-deficient eggs, in which all embryos suddenly die at mid-incubation (days 13-15). This malady, caused by riboflavin deficiency, leads to excessive lipid accumulation in liver, impaired β-oxidation of lipid, and severe hypoglycemia prior to death. We have used high-density chicken microarrays for time-course transcriptional scans of liver in chicken embryos between days 9-15 during this riboflavin-deficiency-induced metabolic catastrophe. For comparison, half of rd/rd embryos (n = 16) were rescued from this calamity by injection of riboflavin just prior to incubation of fertile eggs from rd/rd hens., Results: No significant differences were found between hepatic transcriptomes of riboflavin-deficient and riboflavin-rescued embryos at the first two ages (days 9 and 11). Overall, we found a 3.2-fold increase in the number of differentially expressed hepatic genes between day 13 (231 genes) and day 15 (734 genes). Higher expression of genes encoding the chicken flavoproteome was more evident in rescued- (15 genes) than in deficient-embryos (4 genes) at day 15. Diminished activity of flavin-dependent enzymes in riboflavin-deficient embryos blocks catabolism of yolk lipids, which normally serves as the predominant source of energy required for embryonic development., Conclusions: Riboflavin deficiency in mid-stage embryos leads to reduced expression of numerous genes controlling critical functions, including β-oxidation of lipids, blood coagulation and feathering. Surprisingly, reduced expression of feather keratin 1 was found in liver of riboflavin-deficient embryos at e15, which could be related to their delayed feathering and sparse clubbed down. A large number of genes are expressed at higher levels in liver of riboflavin-deficient embryos; these up-regulated genes control lipid storage/transport, gluconeogenesis, ketogenesis, protein catabolism/ubiquitination and cell death.

Furbearer Management in North America maintains wild furbearer populations at sustainably harvestable, scientifically determined and socially acceptable levels. Furbearer management impacts numerous wildlife populations and habitats, and human health, safety and property. Achieving balance in the management of furbearers is not always an easy task partly because regulated trapping, a controversial management technique, plays a critical role in this balance. Steps have been taken by wildlife professionals to improve the humaneness of trapping through the development of international standards used to evaluate traps. These efforts will ideally preserve trapping and the many roles it plays in furbearer management and wildlife management in general.

There are barriers to adoption of research-based teaching methods. Professional development workshops may inform faculty of these methods, but effective adoption often does not follow. In addition, newly-minted research-active faculty are often overwhelmed by the many new responsibilities (grant writing, group management, laboratory setup, teaching) that accompany the position and normally do not have the time to consider novel teaching approaches. This case study documents how over a three-year period, the responsibility for teaching a nontraditional "Introduction to Biochemistry" course in a problem-based learning format was successfully transferred from a senior faculty member nearing retirement (HBW) to a newly-hired research-active assistant professor (CLG). We describe our apprenticeship project involving modeling, scaffolding, fading, and coaching. We suggest that involving faculty in active-learning pedagogy early in their career with mentoring by senior faculty overcomes barriers to adopting these methods. This case describes a specific example from which potentially useful elements can be adopted and adapted wherever biochemistry is taught., (© 2015 The International Union of Biochemistry and Molecular Biology.)

Undergraduates having their first research experience frequently have little idea of what to expect. Institutions offering summer research experiences attempt to address this issue through programs that introduce students to the process and culture of science. However, didactic approaches frequently bore students who prefer more interactive sessions. We describe a "Pass-the-Problem" case study approach that engages groups of students in useful discussions about the research environment they are entering. The cases presented here include keeping a thorough laboratory notebook, balancing laboratory and personal time demands, anxiety about formal presentations, unexpected federal regulatory inspection, working in a lab with limited funds, being used as a technician rather than a researcher, frustration with failed experiments, effects of promotion and tenure on laboratory atmosphere, the importance of reading the research literature, and questioning a career in science. These cases alert students to different situations they might encounter and stimulate discussion about how to deal with them., (© 2015 The International Union of Biochemistry and Molecular Biology.)

Biochemistry and molecular biology (BMB) students should demonstrate proficiency in the foundational concepts of the discipline and possess the skills needed to practice as professionals. To ascertain the skills that should be required, groups of BMB educators met in several focused workshops to discuss the expectations with the ultimate goal of clearly articulating the skills required. The results of these discussions highlight the critical importance of experimental, mathematical, and interpersonal skills including collaboration, teamwork, safety, and ethics. The groups also found experimental design, data interpretation and analysiand the ability to communicate findings to diverse audience to be essential skills. To aid in the development of appropriate assessments these skills are grouped into three categories, 1) Process of Science, 2) Communication and Comprehension of Science, and 3) Community of Practice Aspects of Science. Finally, the groups worked to align these competencies with the best practices in both teaching and in skills assessment., (© 2013 by The International Union of Biochemistry and Molecular Biology.)

The KTeV E799 experiment has conducted a search for the rare decays, K(L)→π(0)π(0)μ(+)μ(-) and K(L)→π(0)π(0)X(0)→π(0)π(0)μ(+)μ(-), where the X(0) is a possible new neutral boson that was reported by the HyperCP experiment with a mass of (214.3 ± 0.5) MeV/c(2). We find no evidence for either decay. We obtain upper limits of Br(K(L)→π(0)π(0)X(0)→π(0)π(0)μ(+)μ(-)) < 1.0 × 10(-10) and Br(K(L)→π(0)π(0)μ(+)μ(-)) < 9.2 × 10(-11) at the 90% confidence level. This result rules out the pseudoscalar X(0) as an explanation of the HyperCP result under the scenario that the dsX(0) coupling is completely real.

The BIO2010 report recommended that students in the life sciences receive a more rigorous education in mathematics and physical sciences. The University of Delaware approached this problem by (1) developing a bio-calculus section of a standard calculus course, (2) embedding quantitative activities into existing biology courses, and (3) creating a new interdisciplinary major, quantitative biology, designed for students interested in solving complex biological problems using advanced mathematical approaches. To develop the bio-calculus sections, the Department of Mathematical Sciences revised its three-semester calculus sequence to include differential equations in the first semester and, rather than using examples traditionally drawn from application domains that are most relevant to engineers, drew models and examples heavily from the life sciences. The curriculum of the B.S. degree in Quantitative Biology was designed to provide students with a solid foundation in biology, chemistry, and mathematics, with an emphasis on preparation for research careers in life sciences. Students in the program take core courses from biology, chemistry, and physics, though mathematics, as the cornerstone of all quantitative sciences, is given particular prominence. Seminars and a capstone course stress how the interplay of mathematics and biology can be used to explain complex biological systems. To initiate these academic changes required the identification of barriers and the implementation of solutions.

Problem-based learning, process-oriented guided inquiry learning, and peer-led team learning are student-centered, active-learning pedagogies commonly used in science education. The characteristic features of each are compared and contrasted to enable new practitioners to decide which approach or combination of approaches will suit their particular situation.

We present a new determination of the parity of the neutral pion via the double Dalitz decay pi0-->e+e-e+e-. Our sample, which consists of 30,511 candidate decays, was collected from KL-->pi0pi0pi0 decays in flight at the KTeV-E799 experiment at Fermi National Accelerator Laboratory. We confirm the negative pi0 parity and place a limit on scalar contributions to the pi0-->e+e-e+e- decay amplitude of less than 3.3% assuming CPT conservation. The pi0gamma*gamma* form factor is well described by a momentum-dependent model with a slope parameter fit to the final state phase-space distribution. Additionally, we have measured the branching ratio of this mode to be B(pi0-->e+e-e+e-)=(3.26+/-0.18)x10(-5).

The Fermilab KTeV experiment has searched for lepton-flavor-violating decays of the K(L) meson in three decay modes. We observe no events in the signal region for any of the modes studied, and we set the following upper limits for their branching ratios at the 90% C.L.: BR(K(L) --> pi(0) micro(+/-) e(-/+)) <7.6 x 10(-11); BR(K(L) --> pi(0)pi(0) micro(+/-) e(-/+)) <1.7 x 10(-10); BR(pi(0) --> micro(+/-) e(-/+)) <3.6 x 10(-10). This result represents a factor of 82 improvement in the branching ratio limit for K(L) --> pi(0) micro(+/-) e(-/+) and is the first reported limit for K(L) --> pi(0)pi(0) micro(+/-) e(-/+).

This Letter is the first report of the K{L}-->pi{+/-}e{-/+}nue{+}e{-} decay. Based on 19 208+/-144 events, we determine the branching fraction, B(K{L}-->pi{+/-}e{-/+}nue{+}e{-}M&#95;{e{+}e{-}}>5 MeV/c{2},E{e{+}e{-}}{*}>30 MeV)=(1.285+/-0.041)x10{-5}, and Gamma(K{e3ee}M{e{+}e{-}}>5 MeV/c{2})/Gamma(K{e3})=[4.57+/-0.04(stat)+/-0.14(syst)]x10{-5}. This ratio agrees with a theoretical prediction based on chiral perturbation theory (ChPT) calculated to O(p{4}). The measured kinematical distributions agree with those predicted by just ChPT O(p{4}), but show significant disagreement with ones predicted by leading-order ChPT.

The E799-II (KTeV) experiment at Fermilab has collected 83 262 K(L)-->e+ e- gamma(gamma) events above a background of 79 events. We measure a decay width, normalized to the K(L)-->pi0pi0pi(D)0 (pi0-->gammagamma, pi0-->gammagamma, pi(D0-->e+ e- gamma(gamma)) decay width, of Gamma(K(L)-->e+e-gamma(gamma))/Gamma(K(L)-->pi0pi0pi(D)0)=(1.3302+/-0.0046(stat)+/-0.0102(syst)) x 10(-3). We also measure parameters of two K(L)gamma*gamma form factor models. In the Bergström-Massó-Singer parametrization, we find Calpha(K*)= -0.517 +/- 0.030(stat) +/- 0.022(syst). We separately fit for the first parameter of the D'Ambrosio-Isidori-Portolés model and find alpha(DIP)= -1.729 +/- 0.043(stat) +/- 0.028(syst).

Molecular evolution provides an interesting context in which to use problem-based learning because it integrates a variety of topics in biology, biochemistry, and molecular biology. This three-stage problem for advanced students deals with the structure, multiple functions, and properties of lactate dehydrogenase isozymes, and the related evolutionary trade offs of gene sharing versus gene duplication among their corresponding genes. It has directive elements that require students to find and read classic articles, review thermodynamic principles, and apply their understanding to a mythical world wherein dinosaurs continued to evolve. The science fiction writing assignment that brings closure to the problem transformed the problem with respect to student interest and engagement., (Copyright © 2007 International Union of Biochemistry and Molecular Biology, Inc.)

A protein lacking one of the 20 common amino acids is a protein lipogram. This open-ended problem-based learning assignment deals with the evolution of proteins with biased amino acid composition. It has students query protein and metabolic databases to test the hypothesis that natural selection has reduced the frequency of each amino acid specifically in the enzymes required for its biosynthesis. Student groups work in parallel on different amino acids and share strategies. Aside from content objectives that integrate knowledge of protein structure, function, synthesis, and evolution, this problem incorporates oral and written presentations, statistical analysis, and substantial decision making. The point of the problem described here is that a deficiency or absence of a particular amino acid in a protein may be more than a chance occurrence and may be driven by natural selection. The challenge is to demonstrate the difference., (Copyright © 2006 International Union of Biochemistry and Molecular Biology, Inc.)