Deciphering cell motility and spatial sensing of intestinal cell types using an ex vivo intestinal model

The intestine is a highly organized tissue with two distinct regions: the crypt and the villus. When stem cells divide at the crypt bottom, half of their progeny migrates upwards towards the villus, where they differentiate into various cell types, including the abundant absorptive enterocytes. However, the precise mechanisms governing this migration and tissue organization remain poorly understood. In this thesis, novel methodologies, such as long-term intravital imaging and decellularization of mouse intestine, are used to study cell type-specific motility within the tissue architecture. Moreover, work in this thesis probes the mechanisms mediating intestinal regeneration and aging, and the clonal competition during tumor development. In paper 1, we employ long-term intravital imaging to identify a greater number of longterm functioning intestinal stem cells (ISCs) in the small intestine compared to the colon. We further investigate this phenomenon by combining intravital imaging and the novel ex vivo live cell imaging assay to discover that stem cells in the small intestine display downward motility directed by Wnt-ligands. In Paper 2, the ex vivo live cell imaging assay was utilized to investigate active cell migration in several cell types. Our findings reveal that both ISCs and paneth cells possess an intrinsic ability to perceive positional cues embedded in the extracellular matrix (ECM), which guides them to their native location, the crypt. In contrast, enterocytes, lack this capability. Finally, we discovered that during aging ECM loses the signals guiding crypt homing of ISCs, and that the tumor-causing mutations render cells insensitive to ECM signals resulting in loss of crypt homing. In Paper 3, we introduce an optimized intestinal decellularization protocol and demonstrate its capacity to regenerate the intestinal epithelium from single-seeded stem cells, freshly isolated crypts, or organoids. During regeneration following damage, we discovered mesenchymally produced Asporin, which promotes Tgfβ-signaling and induces fetal-like reprogramming in intestinal tissue. Additionally, we observed that chronic upregulation of Asporin in the aged intestinal tissue hampers tissue repair. In Paper 4, we elucidate how Apc-mutant ISCs gain a clonal advantage over wild-type ISCs. We reveal that Apc-mutant ISCs secrete the Wnt-inhibitor Notum, which reduces the stemness and competitiveness of wild-type ISCs. Inhibition of Notum reverted the clonal advantage of Apc-mutant cells and reduced tumor burden. In conclusion, this thesis focused on highlighting the interplay between intestinal epithelial cells and the ECM, particularly the ability of ISCs and paneth cells to sense positional cues embedded in the ECM, guiding them to their native location. Additionally, key mechanisms disrupted during aging and in intestinal cancer are elucidated

A Study Of The Causes And Remedies For The Inferiority Complex

In order to study the problem of adolescent maladjustment, clinics have been established to provide tor scientific study or individual cases. The first guidance clinic along the line or individual Psycnoiogy was organized (1912) by Dr. Alfred Adler in Vienna, Austria. Since that time several have been established in various sections of the United States. It was through guidance clinics that psychologists have been able to rind sources of adolescent maladjustment. According to Meyer, Adler, and. Other personality disturbances are the results of undesirable habits which might have been avoided if the individual had received adequate training and proper guidance. According to Valentine, a thwarted ambition may have created in an individual a sense 01 minority, inability, incompleteness, or weakness. The sense of minority may have to do with one\u27s stature, appearance, mentality, or inadequacy in any respect. This study purposes: 1. To determine causes or the inferiority complex. 2. To discover its symptoms as are indicated by behavior. 3. To determine its effect upon the individual. To suggest possible remedies

Rural poverty in Ecuador : a qualitative assessment

A complement to recent in-depth quantitative analyses of rural poverty in Ecuador, this is a report on the results of the Rural Qualitative Assessment in living conditions in rural communities in all three Ecuador's diverse regions. Using a variety of qualitative techniques, the research aimed to assess what poverty means to marginalized rural families, what kind of survival strategies families use in times of hardship, and what these families believe is needed to alleviate poverty. Several key messages emerge: 1) rural communities with the same characteristics (such as area, soil quality, and ethnic background) are actually very heterogeneous in their command of land resources, definition of well-being, range of economic activities, and recommendations for what is needed to overcome poverty; 2) in times of hardship, families have complemented income for traditional sources with earnings from new activities. In addition to migration, which plays a pivotal role in all communities, piecework and weaving are important to income generation in the Sierra, small businesses are important in the Costa, and increased production of cash crops is important in the Oriente. Families have also reduced expenditures on clothing, fiestas, and food. Spending less on food is alarming as malnutrition rates in rural Ecuador are already very high; and 3) poor rural families express very practical solutions to overcoming poverty. They don't demand sweeping changes. Overwhelmingly, they suggest measures that will make available land and human resources more productive. Almost half the suggestions from poor rural families have to do with infrastructure. Many families also want training courses (both agricultural and nonagricultural).Public Health Promotion,Environmental Economics&Policies,Agricultural Knowledge&Information Systems,Health Monitoring&Evaluation,Water Conservation,Environmental Economics&Policies,Agricultural Knowledge&Information Systems,Crops&Crop Management Systems,Health Monitoring&Evaluation,Housing&Human Habitats

Row Covers for Early Tomato Production

Our previous research has shown wavelength selective plastic (SRM-olive) coupled with a row cover has given consistent top early yields. Clear plastic mulch was also superior provided there was excellent weed control. Agribon is a polypropylene spunbond material available in several weights that give various light transmission and frost protection characteristics. It is mostly used as a floating row cover for extended season production, frost protection, and wind and insect control. We tested the traditional slitted clear plastic row cover against the agribon (AG-19, light weight at 0.55 oz/yd2 with 85% light transmission)

Second Language Vocabulary Learning Through Extensive Reading With Audio Support: How Do Frequency and Distribution of Occurrence Affect Learning?

This study investigated (1) the extent of vocabulary learning through reading and listening to 10 graded readers, and (2) the relationship between vocabulary gain and the frequency and distribution of occurrence of 100 target words in the graded readers. The experimental design expanded on earlier studies that have typically examined incidental vocabulary learning from individual texts. Sixty-one Taiwanese participants studied English as a foreign language (EFL) in an extensive reading program or in a more traditional approach structured around a global English course book. A pretest, posttest, and delayed posttest were administered to all participants. The results indicated that vocabulary gains through reading and listening to multiple texts were high. Relative gains were 44.06% after reading the 10 graded readers and 36.66% three months later. The relationships between vocabulary learning and frequency and distribution of occurrence were found to be non-significant, indicating that frequency was perhaps one of many factors that affected learning

Culture Clash: A Case Study of Three Osage Native American Families

Educational Administratio

Robust quantum logic for trapped ion quantum computers

This thesis describes experimental work on implementing single and two qubit gates in ¹⁷¹Yb+ ions using methods suitable for a large scale quantum computer. By combining a magnetic field gradient with microwave and radiofrequency radiation, the spin and motional states of the ions are coupled which allows multi-qubit operations to be performed, as well as providing individual addressing of ions in frequency space. A dressed state qubit is used which exhibits an increase of over two orders of magnitude in the coherence time for a qubit that it is sensitive to the magnetic field gradient. Using this system, single qubit gates are characterised using the technique of randomised benchmarking, resulting in a measured average error per gate of 9(3)x10ˉ⁴. A new type of two qubit gate is experimentally demonstrated, which in comparison to a standard two qubit gate shows significantly increased resilience to two major sources of gate infidelity: heating of the motional mode of the ions during gate operations, and incorrectly set gate field frequencies. These types of errors are expected to become increasingly important with the move towards quantum processors with large numbers of qubits. Using this same technique, a two qubit gate is also demonstrated at a higher initial temperature with a significantly improved fidelity compared to standard methods. These gate techniques are used to demonstrate work towards implementing positiondependent quantum logic, a method which could remove the correlation between the number of ions and the number of gate fields required in a large scale quantum computing architecture. A method to move the dressed state qubit through a magnetic field gradient while preserving quantum information is demonstrated, as well as a method to optimise the phase of a two qubit gate of unknown phase in order to implement a CNOT logic gate. This provides a path forwards to demonstrating a CNOT gate using position-dependent quantum logic

Practising the Space Between: Embodying Belief as an Evangelical Anglican Student

This article explores the formation of British evangelical university students as believers. Drawing on ethnographic fieldwork conducted with a conservative evangelical Anglican congregation in London, I describe how students in this church come to embody a highly cognitive, word-based mode of belief through particular material practices. As they learn to identify themselves as believers, practices of reflexivity and accountability enable them to develop a sense of narrative coherence in their lives that allows them to negotiate tensions that arise from their participation in church and broader social structures. I demonstrate that propositional belief – in contexts where it becomes an identity marker – is bound up with relational practices of belief, such that distinctions between “belief in” and “belief that” are necessarily blurred in the lives of young evangelicals