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BURROWING AND WALKING MECHANISMS OF NORTH AMERICAN MOLES
Moles (Family Talpidae) are a classic example of extreme specialization, in their case highly derived forelimb morphologies associated with burrowing. Despite many observations of mole burrows and behaviors gathered in the field, we know very little about how and how well moles use their forelimbs to dig tunnels and to walk within the built tunnels to collect and transport food. The first chapter investigates the effect of soil compactness on two sympatric mole species under controlled laboratory conditions. My results demonstrate that increasing soil compactness impedes tunneling performance as evidenced by reduced burrowing speed, increased soil transport, shorter tunnels, shorter activity time, and less time spent burrowing continuously. Furthermore, differences in performance between the two mole species may be associated with differences in the structure and extent of their burrow systems or the morphology of their forelimbs. The second chapter investigates the kinematics of Eastern moles burrowing in loose and compact substrates. Using XROMM (X-ray Reconstruction of Moving Morphology), I found that moles move substrate dorsally using elevating strokes in loose substrates and laterally using scratching strokes in compact substrates. They do not move the substrate caudally like most mammalian forelimb diggers. Furthermore, my results demonstrate that the combination of stereotypic movements of the shoulder joint, where the largest digging muscles are located, and flexibility in elbow and wrist joints makes moles extremely effective diggers in both loose and compact substrates. In the third chapter I test two hypotheses about forelimb movements during walking. The first is that moles move their shoulders by humeral long-axis rotation, as they do during burrowing and in walking echidnas. The second is that moles move their shoulders by flexion and extension in the horizontal plane, similar to sprawling reptiles. Surprisingly, my results reject both hypotheses and indicate that the way moles walk is different from that of all tetrapods that have been studied. The results of my dissertation open new horizons in the study of morphological, physiological, behavioral and ecological evolution of fossoriality, and may provide new ideas for the design of bio-inspired robots used for urban search and rescue
Poly[[μ-1,4-bis(4,5-dihydro-1,3-oxazol-2-yl)benzene-κ2 N:N′]di-μ-bromido-cadmium]
In the title coordination polymer, [CdBr2(C12H12N2O2)]n, the CdII ion, situated on an inversion centre, is coordinated by four bridging Br atoms and two N atoms from two 1,4-bis(4,5-dihydro-1,3-oxazol-2-yl)benzene (L) ligands in a distorted octahedral geometry. The L ligand, which also lies across an inversion centre, bridges two CdII ions, forming layers parallel to (010)
Cordycepin Induced MA-10 Mouse Leydig Tumor Cell Apoptosis through Caspase-9 Pathway
In the present study, the apoptotic effect of cordycepin on MA-10 cells, a mouse Leydig tumor cell line, was investigated. Results demonstrated that the number of rounding-up cell increased by cordycepin (10 μM to 5 mM for 24 h), and cells with plasma membrane blebbing could be observed by 100 μM cordycepin. In viability test, MA-10 cell surviving rate significantly decreased as the dosage (10 μM to 5 mM) and duration (3–24 h) of cordycepin treatment increased (P < 0.05). Cordycepin at 100 μM and 1 mM for 24 h treatment induced significant DNA fragmentation (P < 0.05). In addition, the percentage of G1 and G2/M phase cell significantly declined by cordycepin (100 μM and 1 mM) for 24 h treatment, while the percentages of subG1 phase cell increased by 100 μM and/or 1 mM cordycepin in 6, 12 and 24 h treatments (P < 0.05), respectively, which highly suggested that cordycepin induced MA-10 cell apoptosis. In mechanism study with the treatments of caspases, c-Jun NH2 terminal kinase (JNK) or reactive oxygen species (ROS) inhibitors plus cordycepin for 24 h, only caspases inhibitor suppressed subG1 phase in MA-10 cells. Moreover, western blotting results showed that cordycepin induced caspase-9, -3 and -7 protein expressions, but not caspase-8, in time- and dose-dependent manners. In conclusion, cordycepin induced apoptosis in MA-10 mouse Leydig tumor cells through a caspase-9 and -3 and -7 dependent pathway
Green benches: What can the People's Republic of China learn from environment courts of other countries?
The rapid economic growth of the People’s Republic of China (PRC) over the last 30 years has generated many environmental problems and a concomitant rise in the number of environmental disputes. Until 1989, legal cases arising from these disputes were usually heard in the people’s courts of general jurisdiction. In that year, however, the development of the environment court system accelerated, leading to the creation of 11 such courts for pilot cases, a sign of the high priority the PRC has given to environmental protection over the past two decades. This paper examines the effectiveness of environment courts in the PRC and elsewhere, so that the lessons learned can be applied in the PRC and in other developing countries. It also recommends ways to promote environmental justice in the PRC, given that the 11 environment courts are no longer enough to handle the rapidly increasing caseload throughout the country
Poly[(acetato-κ2 O,O′)aqua(μ4-1H-benzimidazole-5,6-dicarboxylato-κ5 N 3:O 5,O 5′:O 5,O 6:O 6′)praseodymium(III)]
In the title complex, [Pr(C9H4N2O4)(C2H3O2)(H2O)]n, the PrIII ion is coordinated by five O atoms and one N atom from four benzimidazole-5,6-dicarboxylate ligands, two O atoms from an acetate ligand and one water molecule, giving a tricapped trigonal-prismatic geometry. The benzimidazole-5,6-dicarboxylate and acetate ligands connect the PrIII ions, forming a layer in the ac plane; the layers are further linked by N—H⋯O and O—H⋯O hydrogen bonding and π–π stacking interactions between neighboring pyridine rings [the centroid–centroid distance is 3.467 (1) Å], assembling a three-dimensional supramolecular network. The acetate methyl group is disordered over two positions with site-occupancy factors of 0.75 and 0.25
Benzoylmethyl 4-chlorobenzoate
The asymmetric unit of the title compound, C15H11ClO3, contains three molecules, A, B, and C. Molecules A and B are aligned edge-to-face, whereas molecules B and C are aligned almost parallel to each other. The crystal structure displays C—H⋯π and π–π [centroid–centroid distances of 3.960 (4), 3.971 (4) and 3.971 (4) for molecules A, B and C, respectively] parallel-displaced interactions, and C—H⋯O hydrogen bonds
A Study on Differentiable Logic and LLMs for EPIC-KITCHENS-100 Unsupervised Domain Adaptation Challenge for Action Recognition 2023
In this technical report, we present our findings from a study conducted on
the EPIC-KITCHENS-100 Unsupervised Domain Adaptation task for Action
Recognition. Our research focuses on the innovative application of a
differentiable logic loss in the training to leverage the co-occurrence
relations between verb and noun, as well as the pre-trained Large Language
Models (LLMs) to generate the logic rules for the adaptation to unseen action
labels. Specifically, the model's predictions are treated as the truth
assignment of a co-occurrence logic formula to compute the logic loss, which
measures the consistency between the predictions and the logic constraints. By
using the verb-noun co-occurrence matrix generated from the dataset, we observe
a moderate improvement in model performance compared to our baseline framework.
To further enhance the model's adaptability to novel action labels, we
experiment with rules generated using GPT-3.5, which leads to a slight decrease
in performance. These findings shed light on the potential and challenges of
incorporating differentiable logic and LLMs for knowledge extraction in
unsupervised domain adaptation for action recognition. Our final submission
(entitled `NS-LLM') achieved the first place in terms of top-1 action
recognition accuracy.Comment: Technical report submitted to CVPR 2023 EPIC-Kitchens challenge
β-Lapachone induces heart morphogenetic and functional defects by promoting the death of erythrocytes and the endocardium in zebrafish embryos
<p>Abstract</p> <p>Background</p> <p>β-Lapachone has antitumor and wound healing-promoting activities. To address the potential influences of various chemicals on heart development of zebrafish embryos, we previously treated zebrafish embryos with chemicals from a Sigma LOPAC1280™ library and found several chemicals including β-lapachone that affected heart morphogenesis. In this study, we further evaluated the effects of β-lapachone on zebrafish embryonic heart development.</p> <p>Methods</p> <p>Embryos were treated with β-lapachone or dimethyl sulfoxide (DMSO) at 24 or 48 hours post fertilization (hpf) for 4 h at 28°C. Heart looping and valve development was analyzed by whole-mount <it>in situ </it>hybridization and histological analysis. For fractional shortening and wall shear stress analyses, AB and Tg (<it>gata1</it>:<it>DsRed</it>) embryos were recorded for their heart pumping and blood cell circulations via time-lapse fluorescence microscopy. Dextran rhodamine dye injection into the tail reticular cells was used to analyze circulation. Reactive oxygen species (ROS) was analyzed by incubating embryos in 5-(and 6-)-chloromethyl-2',7'-dichloro-dihydrofluorescein diacetate (CM-H<sub>2</sub>DCFDA) and recorded using fluorescence microscopy. <it>o</it>-Dianisidine (ODA) staining and whole mount <it>in situ </it>hybridization were used to analyze erythrocytes. TUNEL assay was used to examine DNA fragmentation.</p> <p>Results</p> <p>We observed a linear arrangement of the ventricle and atrium, bradycardia arrhythmia, reduced fractional shortening, circulation with a few or no erythrocytes, and pericardial edema in β-lapachone-treated 52-hpf embryos. Abnormal expression patterns of <it>cmlc2</it>, <it>nppa</it>, <it>BMP4</it>, <it>versican</it>, and <it>nfatc1</it>, and histological analyses showed defects in heart-looping and valve development of β-lapachone-treated embryos. ROS production was observed in erythrocytes and DNA fragmentation was detected in both erythrocytes and endocardium of β-lapachone-treated embryos. Reduction in wall shear stress was uncovered in β-lapachone-treated embryos. Co-treatment with the NQO1 inhibitor, dicoumarol, or the calcium chelator, BAPTA-AM, rescued the erythrocyte-deficiency in circulation and heart-looping defect phenotypes in β-lapachone-treated embryos. These results suggest that the induction of apoptosis of endocardium and erythrocytes by β-lapachone is mediated through an NQO1- and calcium-dependent pathway.</p> <p>Conclusions</p> <p>The novel finding of this study is that β-lapachone affects heart morphogenesis and function through the induction of apoptosis of endocardium and erythrocytes. In addition, this study further demonstrates the importance of endocardium and hemodynamic forces on heart morphogenesis and contractile performance.</p
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