Bacterioplankton dispersal and biogeochemical function across Alaskan Arctic catchments.

In Arctic catchments, bacterioplankton are dispersed through soils and streams, both of which freeze and thaw/flow in phase, seasonally. To characterize this dispersal and its potential impact on biogeochemistry, we collected bacterioplankton and measured stream physicochemistry during snowmelt and after vegetation senescence across multiple stream orders in alpine, tundra, and tundra-dominated-by-lakes catchments. In all catchments, differences in community composition were associated with seasonal thaw, then attachment status (i.e. free floating or sediment associated), and then stream order. Bacterioplankton taxonomic diversity and richness were elevated in sediment-associated fractions and in higher-order reaches during snowmelt. Families Chthonomonadaceae, Pyrinomonadaceae, and Xiphinematobacteraceae were abundantly different across seasons, while Flavobacteriaceae and Microscillaceae were abundantly different between free-floating and sediment-associated fractions. Physicochemical data suggested there was high iron (Fe+ ) production (alpine catchment); Fe+ production and chloride (Cl- ) removal (tundra catchment); and phosphorus (SRP) removal and ammonium (NH4 + ) production (lake catchment). In tundra landscapes, these 'hot spots' of Fe+ production and Cl- removal accompanied shifts in species richness, while SRP promoted the antecedent community. Our findings suggest that freshet increases bacterial dispersal from headwater catchments to receiving catchments, where bacterioplankton-mineral relations stabilized communities in free-flowing reaches, but bacterioplankton-nutrient relations stabilized those punctuated by lakes.

Unmixing multi-spectral electrical impedance tomography (EIT) predicts clinical-standard controlled attenuation parameter (CAP) for nonalcoholic fatty liver disease classification: a feasibility study.

Here, we tested the feasibility of predicting CAP with multi-spectral EIT. Conductivity and CAP were acquired from nonalcoholic fatty liver disease patients using a portable EIT system and vibration-controlled transient elastography (VCTE). We then used frequency-difference conductivity and waist-over-height as prediction features to estimate CAP and found an adj. R2 of 0.92. We further developed a novel prediction method by incorporating EIT spectral unmixing reconstruction and demonstrated an improvement in CAP estimation. Last, we optimized the EIT acquisition process by minimizing the total variance of the CAP estimator. Clinical Relevance: EIT can estimate clinical-standard liver disease classification. This portable EIT system is potentially cost-effective and self-administrable with short acquisition time (3 mins), while VCTE are costly and usually requires a trained personnel to operate with longer acquisition time (5-10 mins).

Citizen science reveals unexpected solute patterns in semiarid river networks.

Human modification of water and nutrient flows has resulted in widespread degradation of aquatic ecosystems. The resulting global water crisis causes millions of deaths and trillions of USD in economic damages annually. Semiarid regions have been disproportionately affected because of high relative water demand and pollution. Many proven water management strategies are not fully implemented, partially because of a lack of public engagement with freshwater ecosystems. In this context, we organized a large citizen science initiative to quantify nutrient status and cultivate connection in the semiarid watershed of Utah Lake (USA). Working with community members, we collected samples from ~200 locations throughout the 7,640 km2 watershed on a single day in the spring, summer, and fall of 2018. We calculated ecohydrological metrics for nutrients, major ions, and carbon. For most solutes, concentration and leverage (influence on flux) were highest in lowland reaches draining directly to the lake, coincident with urban and agricultural sources. Solute sources were relatively persistent through time for most parameters despite substantial hydrological variation. Carbon, nitrogen, and phosphorus species showed critical source area behavior, with 10-17% of the sites accounting for most of the flux. Unlike temperate watersheds, where spatial variability often decreases with watershed size, longitudinal variability showed an hourglass shape: high variability among headwaters, low variability in mid-order reaches, and high variability in tailwaters. This unexpected pattern was attributable to the distribution of human activity and hydrological complexity associated with return flows, losing river reaches, and diversions in the tailwaters. We conclude that participatory science has great potential to reveal ecohydrological patterns and rehabilitate individual and community relationships with local ecosystems. In this way, such projects represent an opportunity to both understand and improve water quality in diverse socioecological contexts.

"The man who committed a hundred burglaries": Mark Benney's strange and eventful sociological career.

This article examines the life and career of the sociologist Mark Benney. It describes the processes, not all of them edifying, by which he made the transition from life as a career criminal, via literature, to become a sociologist first at the London School of Economics and then at the University of Chicago. Benney's career is then used to illuminate particular episodes in the history of sociology, including the attempt to introduce into British sociology in the period after the Second World War quantitative survey techniques of the kind that were then becoming more widely used in the United States, and his work with David Riesman on the Interview Project, Riesman's attempt to develop a empirically based sociology of the interview.

"The most important technique ": Carl Rogers, Hawthorne, and the rise and fall of nondirective interviewing in sociology.

In the 1940s, interviewing practice in sociology became decisively influenced by techniques that had originally been developed by researchers in other disciplines working within a number of therapeutic or quasi-therapeutic contexts, in particular the "nondirective interviewing" methods developed by Carl Rogers and the interviewing procedures developed during the Hawthorne studies. This article discusses the development of nondirective interviewing and looks at how in the 1930s and '40s the approach came to be used in sociology. It examines the factors leading to both the popularity of the method and its subsequent fall from favor.

The dynamics of cardiolipin synthesis post-mitochondrial fusion.

Alteration in mitochondrial fusion may regulate mitochondrial metabolism. Since the phospholipid cardiolipin (CL) is required for function of the mitochondrial respiratory chain, we examined the dynamics of CL synthesis in growing Hela cells immediately after and 12h post-fusion. Cells were transiently transfected with Mfn-2, to promote fusion, or Mfn-2 expressing an inactive GTPase for 24h and de novo CL biosynthesis was examined immediately after or 12h post-fusion. Western blot analysis confirmed elevated Mfn-2 expression and electron microscopic analysis revealed that Hela cell mitochondrial structure was normal immediately after and 12h post-fusion. Cells expressing Mfn-2 exhibited reduced CL de novo biosynthesis from [1,3-(3)H]glycerol immediately after fusion and this was due to a decrease in phosphatidylglycerol phosphate synthase (PGPS) activity and its mRNA expression. In contrast, 12h post-mitochondrial fusion cells expressing Mfn-2 exhibited increased CL de novo biosynthesis from [1,3-(3)H]glycerol and this was due to an increase in PGPS activity and its mRNA expression. Cells expressing Mfn-2 with an inactive GTPase activity did not exhibit alterations in CL de novo biosynthesis immediately after or 12h post-fusion. The Mfn-2 mediated alterations in CL de novo biosynthesis were not accompanied by alterations in CL or monolysoCL mass. [1-(14)C]Oleate incorporation into CL was elevated at 12h post-fusion indicating increased CL resynthesis. The reason for the increased CL resynthesis was an increased mRNA expression of tafazzin, a mitochondrial CL resynthesis enzyme. Ceramide-induced expression of PGPS in Hela cells or in CHO cells did not alter expression of Mfn-2 indicating that Mfn-2 expression is independent of altered CL synthesis mediated by elevated PGPS. In addition, Mfn-2 expression was not altered in Hela cells expressing phospholipid scramblase-3 or a disrupted scramblase indicating that proper CL localization within mitochondria is not essential for Mfn-2 expression. The results suggest that immediately post-mitochondrial fusion CL de novo biosynthesis is "slowed down" and then 12h post-fusion it is "upregulated". The implications of this are discussed.

Young women's accounts of factors influencing their use and non-use of emergency contraception: in-depth interview study.

OBJECTIVES: To explore young women's accounts of their use and non-use of emergency contraception. DESIGN: Qualitative study using in-depth interviews. PARTICIPANTS: 30 women aged 16-25; participants from socially deprived inner city areas were specifically included. SETTING: Community, service, and educational settings in England. RESULTS: Young women's accounts of their non-use of emergency contraception principally concerned evaluations of the risk conferred by different contraceptive behaviours, their evaluations of themselves in needing emergency contraception, and personal difficulties in asking for emergency contraception. CONCLUSIONS: The attitudes and concerns of young women, especially those from disadvantaged backgrounds, may make them less able or willing than others to take advantage of recent increases in access to emergency contraception. Interventions that aim to increase the use of emergency contraception need to address the factors that influence young women's non-use of emergency contraception.