6-Benz­yloxy-2-phenyl­pyridazin-3(2H)-one

In the title compound, C17H14N2O2, the central pyridazine ring forms dihedral angles of 47.29 (5) and 88.54 (5)° with the benzene rings, while the dihedral angle between the benzene rings is 62.68 (6)°. In the crystal, molecules are linked by two weak C—H⋯O hydrogen bonds and three weak C—H⋯π inter­actions

Observational Constraints on Exponential Gravity

We study the observational constraints on the exponential gravity model of f(R)=-beta*Rs(1-e^(-R/Rs)). We use the latest observational data including Supernova Cosmology Project (SCP) Union2 compilation, Two-Degree Field Galaxy Redshift Survey (2dFGRS), Sloan Digital Sky Survey Data Release 7 (SDSS DR7) and Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP7) in our analysis. From these observations, we obtain a lower bound on the model parameter beta at 1.27 (95% CL) but no appreciable upper bound. The constraint on the present matter density parameter is 0.245< Omega_m^0<0.311 (95% CL). We also find out the best-fit value of model parameters on several cases.Comment: 14pages, 3 figures, accepted by PR

An LSTM Based Generative Adversarial Architecture for Robotic Calligraphy Learning System

Robotic calligraphy is a very challenging task for the robotic manipulators, which can sustain industrial manufacturing. The active mechanism of writing robots require a large sized training set including sequence information of the writing trajectory. However, manual labelling work on those training data may cause the time wasting for researchers. This paper proposes a machine calligraphy learning system using a Long Short-Term Memory (LSTM) network and a generative adversarial network (GAN), which enables the robots to learn and generate the sequences of Chinese character stroke (i.e., writing trajectory). In order to reduce the size of the training set, a generative adversarial architecture combining an LSTM network and a discrimination network is established for a robotic manipulator to learn the Chinese calligraphy regarding its strokes. In particular, this learning system converts Chinese character stroke image into the trajectory sequences in the absence of the stroke trajectory writing sequence information. Due to its powerful learning ability in handling motion sequences, the LSTM network is used to explore the trajectory point writing sequences. Each generation process of the generative adversarial architecture contains a number of loops of LSTM. In each loop, the robot continues to write by following a new trajectory point, which is generated by LSTM according to the previously written strokes. The written stroke in an image format is taken as input to the next loop of the LSTM network until the complete stroke is finally written. Then, the final output of the LSTM network is evaluated by the discriminative network. In addition, a policy gradient algorithm based on reinforcement learning is employed to aid the robot to find the best policy. The experimental results show that the proposed learning system can effectively produce a variety of high-quality Chinese stroke writing

Kinetic Studies on Radical Scavenging Activity of Kaempferol Decreased by Sn(II) Binding

Sn(II) binds to kaempferol (HKaem, 3,4&prime;,5,7-tetrahydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one) at the 3,4-site forming [Sn(II)(Kaem)2] complex in ethanol. DPPH&bull; scavenging efficiency of HKaem is dramatically decreased by SnCl2 coordination due to formation of acid inhibiting deprotonation of HKaem as ligands and thus reduces the radical scavenging activity of the complex via a sequential proton-loss electron transfer (SPLET) mechanism. Moderate decreases in the radical scavenging of HKaem are observed by Sn(CH3COO)2 coordination and by contact between Sn and HKaem, in agreement with the increase in the oxidation potential of the complex compared to HKaem, leading to a decrease in antioxidant efficiency for fruits and vegetables with Sn as package materials

Organochlorinated pesticides expedite the enzymatic degradation of DNA

Extracellular DNA in the environment may play important roles in genetic diversity and biological evolution. However, the influence of environmental persistent organic contaminants such as organochlorinated pesticides (e.g., hexachlorocyclohexanes [HCHs]) on the enzymatic degradation of extracellular DNA has not been elucidated. In this study, we observed expedited enzymatic degradation of extracellular DNA in the presence of α-HCH, β-HCH and γ-HCH. The HCH-expedited DNA degradation was not due to increased deoxyribonuclease I (DNase I) activity. Our spectroscopic and computational results indicate that HCHs bound to DNA bases (most likely guanine) via Van der Waals forces and halogen bonds. This binding increased the helicity and accumulation of DNA base pairs, leading to a more compact DNA structure that exposed more sites susceptible to DNase I and thus expedited DNA degradation. This study provided insight into the genotoxicity and ecotoxicity of pesticides and improved our understanding of DNA persistence in contaminated environments

Survival Outcomes of Patients with Esophageal Cancer Who Did Not Proceed to Surgery after Neoadjuvant Treatment

Background: This retrospective study examined outcomes in esophageal squamous cell carcinoma (ESCC) patients who did not undergo surgical resection after neoadjuvant chemoradiotherapy (nCRT). Methods: Patients receiving nCRT between 2012 and 2020 were divided into two groups: group 1 (scheduled surgery) and group 2 (no surgery). Group 2 was further categorized into subgroups based on reasons for not proceeding to surgery: group 2a (disease progression), group 2b (poor general conditions), and group 2c (patient refusal). Overall survival (OS) was the primary outcome. Results: Group 1 comprised 145 patients, while subgroups 2a, 2b, and 2c comprised 24, 16, and 31 patients, respectively. The 3-year OS rate was significantly lower in group 2 compared with group 1 (34% versus 56%, p &lt; 0.001). A subgroup analysis showed varying 3-year OS rates: 13% for group 2a, 25% for group 2b, and 58% for group 2c (p &lt; 0.001). Propensity score matching for group 2c and group 1 revealed no significant difference in 3-year OS rates (p = 0.91). Conclusion: One-third of ESCC patients receiving nCRT did not undergo surgical resection. Overall survival in this group was generally poorer, except for those who refused surgery (group 2c).</p

BMPRIA mediated signaling is essential for temporomandibular joint development in mice

The central importance of BMP signaling in the development and homeostasis of synovial joint of appendicular skeleton has been well documented, but its role in the development of temporomandibular joint (TMJ), also classified as a synovial joint, remains completely unknown. In this study, we investigated the function of BMPRIA mediated signaling in TMJ development in mice by transgenic loss-of- and gain-of-function approaches. We found that BMPRIA is expressed in the cranial neural crest (CNC)-derived developing condyle and glenoid fossa, major components of TMJ, as well as the interzone mesenchymal cells. Wnt1-Cre mediated tissue specific inactivation of BmprIa in CNC lineage led to defective TMJ development, including failure of articular disc separation from a hypoplastic condyle, persistence of interzone cells, and failed formation of a functional fibrocartilage layer on the articular surface of the glenoid fossa and condyle, which could be at least partially attributed to the down-regulation of Ihh in the developing condyle and inhibition of apoptosis in the interzone. On the other hand, augmented BMPRIA signaling by Wnt1-Cre driven expression of a constitutively active form of BmprIa (caBmprIa) inhibited osteogenesis of the glenoid fossa and converted the condylar primordium from secondary cartilage to primary cartilage associated with ectopic activation of Smad-dependent pathway but inhibition of JNK pathway, leading to TMJ agenesis. Our results present unambiguous evidence for an essential role of finely tuned BMPRIA mediated signaling in TMJ development

Modified Weekly Cisplatin-Based Chemotherapy Is Acceptable in Postoperative Concurrent Chemoradiotherapy for Locally Advanced Head and Neck Cancer

Background. Triweekly cisplatin-based postoperative concurrent chemoradiotherapy (CCRT) has high intolerance and toxicities in locally advanced head and neck cancer (LAHNC). We evaluated the effect of a modified weekly cisplatin-based chemotherapy in postoperative CCRT. Methods. A total of 117 patients with LAHNC were enrolled between December 2007 and December 2012. Survival, compliance/adverse events, and independent prognostic factors were analyzed. Results. Median follow-up time was 30.0 (3.1–73.0) months. Most patients completed the entire course of postoperative CCRT (radiotherapy ≥ 60 Gy, 94.9%; ≥6 times weekly chemotherapy, 75.2%). Only 17.1% patients required hospital admission. The most common adverse effect was grade 3/4 mucositis (28.2%). No patient died due to protocol-related adverse effects. Multivariate analysis revealed the following independent prognostic factors: oropharyngeal cancer, extracapsular spread, and total radiation dose. Two-year progression-free survival and overall survival rates were 70.9% and 79.5%, respectively. Conclusion. Modified weekly cisplatin-based chemotherapy is an acceptable regimen in postoperative CCRT for LAHNC