Assessing Infinitism

I will be examining the historical context in which infinitism emerged as a response to coherentism and foundationalism, focusing on the principle of avoiding circularity and principle of avoiding arbitrariness. Coherentism is the idea that knowledge is derived from the coherence of interconnected beliefs, while foundationalism holds that certain basic beliefs serve as the foundation for all other knowledge. Infinitism, on the other hand, suggests that there is no foundational level of knowledge, and that our beliefs can be justified by an infinite regress of reasons, i.e. of non-repeating infinite chains. I will then emphasize the key arguments for and against infinitism, delving into Peter D. Klein - Carl Ginet Debate (Possibility of Non-Inferential Justification), Turri’s notion on ‘how foundationalist can provide for the infinite chain of justifications’ and discuss Richard Fumerton’s objections against Infinitism. Finally, I will evaluate the current state of the debate surrounding infinitism and consider possible future directions for research in this area. Overall, this article aims to provide a comprehensive overview of the concept of infinitism and its role as an alternative to coherentism and foundationalism in epistemology

Directional Phytoscreening: Contaminant Gradients in Trees for Plume Delineation

Tree Sampling Methods Have Been Used in Phytoscreening Applications to Delineate Contaminated Soil and Groundwater, Augmenting Traditional Investigative Methods that Are Time-Consuming, Resource-Intensive, Invasive, and Costly. in the Past Decade, Contaminant Concentrations in Tree Tissues Have Been Shown to Reflect the Extent and Intensity of Subsurface Contamination. This Paper Investigates a New Phytoscreening Tool: Directional Tree Coring, a Concept Originating from Field Data that Indicated Azimuthal Concentrations in Tree Trunks Reflected the Concentration Gradients in the Groundwater Around the Tree.To Experimentally Test This Hypothesis, Large Diameter Trees Were Subjected to Subsurface Contaminant Concentration Gradients in a Greenhouse Study. These Trees Were Then Analyzed for Azimuthal Concentration Gradients in Aboveground Tree Tissues, Revealing Contaminant Centroids Located on the Side of the Tree Nearest the Most Contaminated Groundwater. Tree Coring at Three Field Sites Revealed Sufficiently Steep Contaminant Gradients in Trees Reflected Nearby Groundwater Contaminant Gradients. in Practice, Trees Possessing Steep Contaminant Gradients Are Indicators of Steep Subsurface Contaminant Gradients, Providing Compass-Like Information About the Contaminant Gradient, Pointing Investigators toward Higher Concentration Regions of the Plume. © 2013 American Chemical Society

Using human induced pluripotent stem cells to investigate neurodevelopmental effects of human cytomegalovirus

Human cytomegalovirus (HCMV) is one of the leading prenatal causes of mental retardation and congenital deformities, world-wide. Its pathogenesis has generally been investigated using animal models. Human studies in vitro have been limited to neurospheres prepared using forebrain tissues from fetal abortuses. This approach is limited and does not permit analysis of individual specific cells. We generated iPS cells from adult human fibroblasts. iPS cells were differentiated into neurospheres, that were expanded as monolayer culture of neuroprogenitors (NPs). Furthermore, neurospheres were differentiated into neurons that could be stained for Tuj1, tyrosine hydroxylase and NR4A2. Functional competency was confirmed by live imaging of intracellular calcium. NPs and neurons were infected with HCMV (MOI = 3). Cell viability was assessed by FACS analysis. Cytopathic effects of HCMV were observed on the 10th day post infection in neuroprogenitor cells. Earlier, the adherence of these cells to the matrix was reduced. Neurons were much more refractory. Reduced cell density and shortening of neuritic processes was only observed at day 15 after infection. We are presently examining the intracellular effects of HCMV. Human iPS cells can efficiently generate neurospheres, which can be expanded as almost pure cultures of neuroprogenitors or differentiated into neurons. iPS cells-derived NP and neurons offer powerful cellular models to investigate the effect of neurotropic viral agents on neurodevelopment

Fine-mapping reveals novel alternative splicing of the dopamine transporter

Center for Human Genetic Research, Massachusetts General Hospital and Department of Neurology, Harvard Medical School, Harvard University, Boston, Massachusetts.Graduate Program in Biology and Biomedical Science, Yale University, New Haven, Connecticut.The dopamine transporter gene (, ) has been implicated in the pathogenesis of numerous psychiatric and neurodevelopmental disorders, including schizophrenia (SZ). We previously detected association between SZ and intronic variants that replicated in two independent Caucasian samples, but had no obvious function. In follow-up analyses, we sequenced the coding and intronic regions of to identify complete linkage disequilibrium patterns of common variations. We genotyped 78 polymorphisms, narrowing the potentially causal region to two correlated clusters of associated SNPs localized predominantly to introns 3 and 4. Our computational analysis of these intronic regions predicted a novel cassette exon within intron 3, designated E3b, which is conserved among primates. We confirmed alternative splicing of E3b in post-mortem human substantia nigra (SN). As E3b introduces multiple in-frame stop codons, the open reading frame is truncated and the spliced product may undergo nonsense mediated decay. Thus, factors that increase E3b splicing could reduce the amount of unspliced product available for translation. Observations consistent with this prediction were made using cellular assays and in post-mortem human SN. In mini-gene constructs, the extent of splicing is also influenced by at least two common haplotypes, so the alternative splicing was evaluated in relation to SZ risk. Meta-analyses across genome-wide association studies did not support the initial associations and further post-mortem studies did not suggest case-control differences in splicing. These studies do not provide a compelling link to schizophrenia. However, the impact of the alternative splicing on other neuropsychiatric disorders should be investigated. © 2010 Wiley-Liss, Inc

The Emergence of Blockchain Technology: A Practical and Secure Approach

This study aims to explore Blockchain technology which is a new technology that has the potential to alter many sectors by making procedures more democratic, safe, transparent, and efficient. Blockchain technology's broad adoption has had a significant influence on how people deal in the digital world. The use of blockchain technology has been expanding across a number of industries as technology advances. Blockchain is an emerging technology that enables smart contracts to perform a variety of processes and different jobs. The foundation of blockchain is smart contracts, which have the ability to replace the position of "middle man" as it can reduce costs, minimize delays, offer more timely and precise data, and improve reporting accuracy. This makes it incredibly difficult for hackers to change or breach blockchain data, especially in a system using a public blockchain. PoC Design is the name given to the new IoT-PoC development process based on extreme programming

\u3ci\u3eIn planta\u3c/i\u3e solid phase sampling devices used in delineating groundwater contaminant plumes

The widespread and indiscriminate use of chlorinated volatile organic compounds as cleaning agents at dry - cleaning facilities, as metal degreasers and solvents in extraction and removal operations has been well documented in the past resulting in releases, while contaminating soil and groundwater. Current techniques to assess chlorinated solvents such as tetrachloroethylene (PCE) and trichloroethylene (TCE) in the subsurface have been time and cost intensive and more importantly invasive to the surrounding environment. New methods use trees as sources of information to access contaminant plume size and plume delineation. The major goal of these research studies has been to save time and money and minimize impact to the surrounding ecosystem, establishing reliable and repeatable results. This study looks at the use of new sampling devices called Solid Phase Samplers (SPSs) and gives insights into the various materials that may find applicability for use as in planta samplers. Laboratory studies included the estimation of the variable uptake kinetics for the materials tested as well as the determination of the material: air partitioning coefficients for chlorinated solvents of interests. These results were then applied in a greenhouse setting as well as in the field to assess sampler material performance. The results indicate that linear low density polyethylene (LLDPE), polydimethylsiloxane (PDMS) and polyvinylchloride (PVC) are the most suitable for use as in planta samplers. These techniques used have great potential as sampling aids in the field of phytoforensics and may further supplement initial site investigations for chlorinated solvents in the subsurface --Abstract, page iv

Conformational investigations of a model polyzwitterion and its applications in oil recovery

Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemical Engineering, June 2017.Cataloged from PDF version of thesis. "June 2017"--Handwritten on title page.Includes bibliographical references.In recent years, nanoparticles have demonstrated immense promise for the development of next generation technologies for subsurface reservoir characterization and oil recovery. Until now however, the scope of such nanoparticles has been limited due to the significant challenge of colloidal stabilization under the extreme salinity and high temperature conditions typical of a reservoir. Previous efforts to address this problem have focused on conventional polyelectrolyte based stabilizers, which unfortunately fail at high ionic strengths due to excessive charge screening. In this thesis, we demonstrate a new approach to stabilization that overcomes this key deficiency, by specifically taking advantage of the excessive charge screening afforded by high ionic strengths. The approach is based on the anti-polyelectrolyte phenomenon, in which screening of intra-chain electrostatic interactions causes a polyzwitterion to undergo a structural transition from a collapsed globule to a more open coil-like regime. We first fundamentally investigate the anti-polyelectrolyte phenomenon in a high density comb type polyzwitterion, poly(sulfobetaine methacrylamide) (polySBMA), via small angle neutron scattering. The phenomenon is probed at a range of molecular weights by utilizing low dispersity homopolymers synthesized via controlled radical polymerization methods. Unique non gaussian behavior with significant molecular weight dependencies of size and shape is observed. An electrostatic dependence for Kuhn length is also established. Subsequently, we extend our understanding of anti-polyelectrolyte systems by characterizing the conformational dependence of polySBMA under conditions such that its responsive swelling is confined due to the segments being bound in three, six and twelve armed star architectures. Chain stretching due to solid angle exclusion, as well as, strong dependencies of size and fractal dimension on electrolyte concentration, number of arms and degree of polymerization (per arm) are noted. After gaining a detailed insight of the anti-polyelectrolyte phenomenon, its unique osmotic response is engineered into electrolyte and temperature responsive polyzwitterionic stabilizers. Robust colloidal stability of silica and polystyrene nanoparticles under reservoir relevant conditions is demonstrated, and the design principles of developing colloidally stable nanoparticles are elucidated. Finally, the polyzwitterion functionalized nanoparticles are leveraged in the form of schizophrenic diblock copolymer functionalized nanoparticles, to develop temperature tunable pickering emulsifiers. In contrast to conventional temperature responsive pickering emulsifiers, which induce phase separation upon heating, the schizophrenic diblock copolymer functionalized nanoparticles are demonstrated to function in the reverse direction, by inducing demulsification upon cooling. The unique temperature response is noted to be cyclable, and is likely to render the particles of important utility in enhanced oil recovery demulsification.by Mikhil Ajay Ranka.Ph. D

Evaluating compliance-without-pressure techniques for increasing participation in online communities

Social psychology offers several theories of potential use for designing techniques to increase user contributions to online communities. Some of these techniques follow the “com-pliance without pressure ” approach, where users are led to comply with a request without being subjected to any obvi-ous external pressure. We evaluated two such techniques – foot-in-the-door and low-ball – in the context of Cyclopath, a geographic wiki. We found that while both techniques suc-ceeded, low-ball elicited more work than foot-in-the-door. We discuss design and research implications of applying these (and other such techniques) in online communities. Author Keywords Increasing participation; social production; online communities; compliance; foot-in-the-door; low-bal

Task Specialization in Social Production Communities: The Case of Geographic Volunteer Work

In social production communities, users' individual and collective efforts lead to the creation of valuable resources — cf. Wikipedia, Open Street Map, and Reddit. Contributors to such communities often specialize in the tasks they choose to do. We found evidence for specialization by work type in Cyclopath, a geographic wiki for bicyclists -- most users edit a single type of map feature, such as points of interest or roads and trails. We also saw a user lifecycle effect: as users gain experience, they specialize in editing roads and trails. Our findings suggest more effective ways to organize social production interfaces, compose units of work, and match them to users who want to help