title: Are bond critical points really critical for hydrogen bonding?

authors: Lane, Joseph R.

subjects: chemistry

abstract: Atoms in Molecules (AIM) theory is routinely used to assess hydrogen bond formation; however its stringent criteria controversially exclude some systems that otherwise appear to exhibit weak hydrogen bonds. We show that a regional analysis of the reduced density gradient, as provided by the recently introduced Non-Covalent Interactions (NCI) index, transcends AIM theory to deliver a chemically intuitive description of hydrogen bonding for a series of 1,n-alkanediols. This regional definition of interactions overcomes the known caveat of only analyzing electron density critical points. In other words, the NCI approach is a simple and elegant generalization of the bond critical point approach, which raises the title question. Namely, is it the presence of an electron density bond critical point that defines a hydrogen bond or the general topology in the region surrounding it?

text: Are bond critical points really critical for hydrogen bonding? Atoms in Molecules (AIM) theory is routinely used to assess hydrogen bond formation; however its stringent criteria controversially exclude some systems that otherwise appear to exhibit weak hydrogen bonds. We show that a regional analysis of the reduced density gradient, as provided by the recently introduced Non-Covalent Interactions (NCI) index, transcends AIM theory to deliver a chemically intuitive description of hydrogen bonding for a series of 1,n-alkanediols. This regional definition of interactions overcomes the known caveat of only analyzing electron density critical points. In other words, the NCI approach is a simple and elegant generalization of the bond critical point approach, which raises the title question. Namely, is it the presence of an electron density bond critical point that defines a hydrogen bond or the general topology in the region surrounding it?

year: 2013

title: Argument-forms which turn invalid over infinite domains: Physicalism as supertask?

authors: Legg, Catherine

subjects: argument-forms

abstract: Argument-forms exist which are valid over finite but not infinite domains. Despite understanding of this by formal logicians, philosophers can be observed treating as valid arguments which are in fact invalid over infinite domains. In support of this claim I will first present an argument against the classical pragmatist theory of truth by Mark Johnston. Then, more ambitiously, I will suggest the fallacy lurks in certain arguments for physicalism taken for granted by many philosophers today.

text: Argument-forms which turn invalid over infinite domains: Physicalism as supertask? Argument-forms exist which are valid over finite but not infinite domains. Despite understanding of this by formal logicians, philosophers can be observed treating as valid arguments which are in fact invalid over infinite domains. In support of this claim I will first present an argument against the classical pragmatist theory of truth by Mark Johnston. Then, more ambitiously, I will suggest the fallacy lurks in certain arguments for physicalism taken for granted by many philosophers today.

year: 2008

title: Place imaginaries: Photography and place-making at Te Awa River Ride

authors: Hill, Rodrigo

subjects: photography

abstract: Contemporary photographic practice has evolved into a field of possibilities, which includes a flux of representational modes that depict experiences, feelings and emotions. This PhD with Creative Practice Components investigates how photography is embedded within ways of knowing, experiencing and making places and the subsequent visual constructions of place imaginaries.  Drawing on contemporary photographic practice and theory, I position myself as a qualitative researcher engaged in creative practice, specifically lens-based approaches and modes of photographic representation. In contrast to photography’s dominant discourse centred on indexical and objective assumptions, I understand photographic practices and images as constructions of multiple meanings.

I use Te Awa River Ride as my research locale, a place where different practices and discourses entangle, forming a diverse set of dynamic and intersecting meanings. Te Awa River Ride is a shared pathway, with a planned total length of 70 kilometres, that edges the banks of the Waikato River from Ngāruawāhia to Cambridge, in the central North Island of Aotearoa New Zealand. I understand Te Awa River Ride as a place-composite, layered by multiple place imaginaries, including indigenous Māori, Pākehā and European ways of meaning and place-making. In this thesis I draw upon place imaginaries as a way of expressing visual possibilities, constructions and affective responses to my own and others’ experiences at this unique research location. 

My photography practice aims to actualise particular place imaginaries through curation and sequencing of lens-based explorations of light, movement and water. This process and the compilation of imagery into curatorial products, such as photography installations, generate novel ways of perceiving the Waikato River and Te Awa River Ride, revealing the centrality of photography in place-making processes.

text: Place imaginaries: Photography and place-making at Te Awa River Ride Contemporary photographic practice has evolved into a field of possibilities, which includes a flux of representational modes that depict experiences, feelings and emotions. This PhD with Creative Practice Components investigates how photography is embedded within ways of knowing, experiencing and making places and the subsequent visual constructions of place imaginaries.  Drawing on contemporary photographic practice and theory, I position myself as a qualitative researcher engaged in creative practice, specifically lens-based approaches and modes of photographic representation. In contrast to photography’s dominant discourse centred on indexical and objective assumptions, I understand photographic practices and images as constructions of multiple meanings.

I use Te Awa River Ride as my research locale, a place where different practices and discourses entangle, forming a diverse set of dynamic and intersecting meanings. Te Awa River Ride is a shared pathway, with a planned total length of 70 kilometres, that edges the banks of the Waikato River from Ngāruawāhia to Cambridge, in the central North Island of Aotearoa New Zealand. I understand Te Awa River Ride as a place-composite, layered by multiple place imaginaries, including indigenous Māori, Pākehā and European ways of meaning and place-making. In this thesis I draw upon place imaginaries as a way of expressing visual possibilities, constructions and affective responses to my own and others’ experiences at this unique research location. 

My photography practice aims to actualise particular place imaginaries through curation and sequencing of lens-based explorations of light, movement and water. This process and the compilation of imagery into curatorial products, such as photography installations, generate novel ways of perceiving the Waikato River and Te Awa River Ride, revealing the centrality of photography in place-making processes.

year: 2019