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0-Hecke algebra actions on flags, polynomials, and Stanley-Reisner rings
(2013-08) Huang, Jia
We study combinatorial aspects of the representation theory of the 0-Hecke algebra $H_n(0)$, a deformation of the group algebra of the symmetric group $\SS_n$. We study the action of $H_n(0)$ on the polynomial ring in $n$ variables. We show that the coinvariant algebra of this action naturally carries the regular representation of $H_n(0)$, giving an analogue of the well-known result for the symmetric group by Chevalley-Shephard-Todd. By investigating the action of $H_n(0)$ on coinvariants and %finite flag varieties, we interpret the generating functions counting the permutations with fixed inverse descent set by their inversion number and major index. We also study the $H_n(0)$-action on the cohomology rings of the Springer fibers, and similarly interpret the (noncommutative) Hall-Littlewood symmetric functions indexed by hook shapes.We generalize the last result from hooks to all compositions by defining an $H_n(0)$-action on the Stanley-Reisner ring of the Boolean algebra. By studying this action we obtain a family of multivariate noncommutative symmetric functions, which specialize to the noncommutative Hall-Littlewood symmetric functions and their $(q,t)$-analogues introduced by Bergeron and Zabrocki, and to a more general family of noncommutative symmetric functions having parameters associated with paths in binary trees introduced recently by Lascoux, Novelli, and Thibon. We also obtain multivariate quasisymmetric function identities from this $H_n(0)$-action, which specialize to results of Garsia and Gessel on generating functions of multivariate distributions of permutation statistics. More generally, for any finite Coxeter group $W$, we define an action of its Hecke algebra $H_W(q)$ on the Stanley-Reisner ring of its Coxeter complex. We find the invariant algebra of this action, and show that the coinvariant algebra of this action is isomorphic to the regular representation of $H_W(q)$ if $q$ is generic. When $q=0$ we find a decomposition for the coinvariant algebra as a multigraded $H_W(0)$-module.
A 0.45 V low power high PSRR subthreshold CMOS voltage reference
(2017-10) Palamedu Sundaram, Prakash
Voltage references are broadly used in analog and digital systems to generate a DC voltage independent of process, supply voltage and temperature (PVT) variations. Conventional band gap references (BGR) add the forward bias voltage across a PN junction with a voltage that is proportional to absolute temperature to produce an output that is insensitive to changes in temperature. BGRs generate a nearly temperature independent reference, of about 1.25 V, and therefore they require a higher supply voltage, which might not meet the low voltage constraints for low-power applications such as passive RFID’s, wearable and implantable medical devices. Also, BGRs use resistors that need more area on silicon. One possible solution to meet the low power requirement is to operate MOSFETs in subthreshold region. Most often, forward biased PN-junctions of BGRs are substituted with MOSFETs biased in the subthreshold region and achieves a supply voltage down to 0.6 V.\par This paper presents a sub-1V voltage reference circuit that has only MOS transistors, all working in subthreshold region with a supply voltage down to 0.45 V and a supply current of 1nA at room temperature for ultra-low power applications. The circuit is designed and simulated in 0.13um technology.
1 vs 2 Matchup as UMD Takes on the Badgers of Wisconsin This Weekend (2017-02-10)
(University of Minnesota Duluth, 2017) Rush, Austin; University of Minnesota Duluth
(1+1) Evolutionary Algorithm on Random Planted Vertex Cover Problems
(2024-03) Kearney, Jack
Evolutionary Algorithms are powerful optimization tools that use the power of randomness and inspiration from biology to achieve results. A common combinatorial optimization problem is the recovery of a minimum vertex cover on some graph 𝐺 = (𝑉, 𝐸). In this work, an evolutionary algorithm will be employed on specific instances of the minimum vertex cover problem containing a random planted solution. This situation is common in data networks and translates to a core set of nodes and larger fringe set that are connected to the core. This study introduces a parameterized analysis of a standard (1+1) Evolutionary Algorithm applied to the random planted distribution of vertex cover problems. When the planted cover is at most logarithmic, restarting the (1+1) EA every 𝑂(𝑛 log 𝑛) steps will, within polynomial time, yield a cover at least as small as the planted cover for sufficiently dense random graphs (𝑝 > 0.71). For superlogarithmic planted covers, the (1+1) EA is proven to find a solution within fixed-parameter tractable time in expectation. To complement these theoretical investigations, a series of computational experiments were conducted, highlighting the intricate interplay between planted cover size, graph density, and runtime. A critical range of edge probability was also investigated.
$1,000 income on Cutover Farms
(University of Minnesota. College of Agriculture. Extension Division, 1941-12) Taylor, M. B.; Wilson, A. D.
1,3-Butadiene-Induced DNA Damage: Ethnic Differences and Sources of Formation
(2022-07) Jokipii Krueger, Caitlin
In the United States, lung cancer is the leading cause of cancer-related deaths. Cigarette smoking is a major risk factor for lung cancer development, with approximately 80% of lung cancer cases directly related to smoking. Up to 1 in 4 smokers will develop lung cancer over the course of their lifetime. This risk varies by racial/ethnic group, with African Americans and Native Hawaiians at greater risk as compared to whites, and Japanese and Latinos at a relatively lower risk than whites. This racial/ethnic difference in risk is not explained by differences in smoking dose, diet, occupation, or socioeconomic status. Cigarette smoke is comprised of over 7000 chemical compounds, more than 70 of which are known human carcinogens. These carcinogens undergo metabolic activation to reactive species which can form adducts with DNA, leading to mutations and eventually lung cancer development. Polymorphisms in metabolic genes responsible for the bioactivation and detoxification of tobacco smoke carcinogens have been hypothesized to play a role in the racial/ethnic differences in lung cancer risk. Among tobacco smoke carcinogens, 1,3-butadiene (butadiene, BD) is one of the most abundant and has the highest cancer risk index. BD is metabolically activated to reactive epoxides 3,4-epoxy-1-butene (EB), 1,2-dihydroxy-3,4-epoxybutane (EBD), and 1,2,3,4-diepoxybutane (DEB) by CYP2E1 and 2A6. These epoxides can be detoxified through glutathione conjugation by GSTT1 to form 2-(N-acetyl-L-cystein-S-yl)-1-hydroxybut-3-ene and 1-(N-acetyl-L-cystein-S-yl)-2-hydroxybut-3-ene (MHBMA) from EB, N-acetyl-S-(3,4-dihydroxybutyl)-L-cysteine (DHBMA) from EB-derived hydroxymethylvinyl ketone (HMVK), 4-(N-acetyl-L-cystein-S-yl)-1,2,3-trihydroxybutane (THBMA) from EBD, and bis-butanediol mercapturic acid (bis-BDMA) from DEB. If not detoxified, these epoxide species can form covalent adducts with DNA such as N7-(1-hydroxy-3-buten-2-yl) guanine (EB-GII) from EB, N7-(2,3,4-trihydroxybut-1-yl) guanine (N7-THBG) from EBD, and 1,4-bis-(guan7-yl)-2,3-butanediol (bis-N7G-BD) from DEB. The first goal of this thesis work was to investigate urinary levels of EB-GII as a biomarker of lung cancer risk in smokers. In Chapter 2 of this thesis, we report the temporal stability and association with smoking of urinary EB-GII. Urinary EB-GII levels were stable over time in smokers, indicating that single adduct measurements provide reliable levels of EB-GII. Additionally, we observed a 34% decrease in the levels of urinary EB-GII upon smoking cessation, indicating that it is associated with smoking status but may also have other sources of formation. In Chapter 3 we quantified urinary EB-GII adducts in smokers and non-smokers belonging to three racial/ethnic groups with differing risks of lung cancer development: Native Hawaiian, white, and Japanese American. We observed higher levels of urinary EB-GII excretion in Japanese Americans as compared to whites and Native Hawaiians and these differences could not be explained by GSTT1 gene deletion or CYP2A6 activity. In Chapter 4 we directly examined the association between urinary EB-GII and lung cancer incidence, revealing that EB-GII levels are elevated in lung cancer cases as compared to smokers without lung cancer (OR = 1.91). In Chapters 2 and 3, we observed that there were low but detectable levels of urinary EB-GII in smokers following smoking cessation and in non-smokers, suggesting additional sources of EB-GII adduct formation. In Chapter 5, we utilized stable isotope tracing to investigate the formation of BD DNA adducts and metabolites from endogenous sources. Laboratory rats were treated with low ppm (0.3-3.0 ppm) concentrations of BD-d6 to approximate occupational exposure to BD (~1 ppm). Levels of exogenous (deuterated) EB-GII, MHBMA, and DHBMA increased in a dose-dependent manner following BD exposure, while endogenous (unlabeled) adducts and metabolites were unaffected by BD dose. While urinary EB-GII and MHBMA were formed primarily by exogenous exposure, significant amounts of endogenous DHBMA were observed. Additionally, urinary exogenous EB-GII was associated with butadiene-induced genomic EB-GII, suggesting that urinary EB-GII can be used as a non-invasive surrogate measurement for genomic BD-DNA damage. In Chapter 6, formation of a novel BD-DNA adduct, N6-[2-deoxy-D-erythro-pentofuranosyl]-2,6-diamino-3,4-dihydro-4-oxo-5-N-1-(oxiran-2-yl)propan-1-ol-formamidopyrimidine (DEB-FAPy-dG) was investigated. A sensitive isotope dilution nanoLC-ESI+-HRMS/MS methodology was developed and applied to quantitation of DEB-FAPy-dG formation in DEB treated calf thymus DNA. DEB-FAPy-dG formation was dependent on DEB concentration and pH, with higher adduct levels observed at higher pH. Detection of DEB-FAPy-dG in mouse embryonic fibroblast cells and nuclei treated with DEB was unsuccessful, likely due to the adduct forming in low quantities at physiological pH.
10 New Features of IOS 10 (2016-09-14)
(University of Minnesota Duluth, 2016) University of Minnesota Duluth
10 Things Everyone Should Know About Nutrition for the Mature Horse
(St. Paul, MN: University of Minnesota Extension Service, 2007) Hathaway, Marcia
Document provides a simple list of 10 items that should be followed for optimal horse health, and continues on to describe the nature and necessity of each item.
10 Things to be Thankful for in Sustainability (2019-11-25)
(University of Minnesota Duluth, 2019-11-25) University of Minnesota Duluth. Office of Sustainability; Schlangen, Kaija
10 UMC Student-Athletes Named to NSIC Winter All-Academic Team
(University of Minnesota Crookston, 2015-03-20) Smith, Shawn
10 years of Calf Research at the Southern Research and Outreach Center (SROC)
(University of Minnesota. Minnesota Extension Service, 2014-09) Chester-Jones, H.; Ziegler, D.M.; Schimek, D.; Ziegler, B.; Golombeski, G.; Raeth-Knight, M.; Cook, D.; Broadwater, N.
10,000 Workflows A Community-Centered Approach to Personal Information Management
(2017-03) Kocher, Megan; Bergland, Kristi; Bishoff, Carolyn; Claussen, Amy; Kempf, Jody; Sayre, Franklin D
A 10,000-year lake-sediment based reconstruction of precipitation isotope values in the Canadian Rocky Mountains and implications for past changes in North American hydroclimate
(2019-01) Wagner, Zachary
Hydroclimate change in the Canadian Rocky Mountains is an important area of research, as demand for water resources in the Great Plains has been continuously increasing in recent years. The population of Alberta has one of the fastest growth rates in Canada, and cities like Calgary and Edmonton are dependent on surface and groundwater resources that originate from precipitation in the mountains. Recent increases in petroleum exploration have also amplified demands for water, along with the growing water requirements of industrial agriculture. The application of sound water resource management policies is essential, and historical records span only ~200 years, a time frame too short to capture the full range of climate variability. The development of paleoclimate proxy records from the Rocky Mountains is therefore necessary to attain a thorough perspective on potential changes in climate. Such data can, for example, inform water resource managers of possible shifts in precipitation seasonality and drought/pluvial events on timescales of decades to millennia. To this end, we present a 10,000-year oxygen isotope record as a proxy for precipitation seasonality linked to the Pacific North American pattern (PNA) which adds to a growing body of research in a region of high spatial complexity of hydroclimate. Shark Lake in Alberta, CA (50.8412°N, 115.3990°W; 1857 m above sea level) is a hydrologically open basin lake in the Canadian Rocky Mountains with one large outlet and numerous small inlets and groundwater springs. Winter precipitation is more depleted in the heavier 18O isotope relative to summer precipitation due to equilibrium fractionation from rain-out and phase changes. δ18O and δD values of Shark Lake water samples (collected during the summer) range from -18.9 to -20.0 ‰ and -141 to -150 ‰, respectively. The annual weighted average precipitation isotope ratios are -16.6 and -126 ‰ for oxygen and hydrogen, respectively. This indicates that Shark Lake principally receives water inputs from runoff or shallow groundwater that originated as precipitation during the cold season. We collected 1 m and 1.5 m long sediment cores using a modified Livingstone corer and used loss-on-ignition (LOI), x-ray diffraction (XRD), x-ray fluorescence (XRF) analyses to destermine sediment texture and composition. The sediment was dated using 14C from terrestrial plant fossils, as well as 210Pb and 137Cs for the surface sediment. We analyzed the isotopic composition (δ18O) of authigenic carbonate sediment from Shark Lake using mass spectrometry and applied these results as a proxy for precipitation seasonality. Lake water oxygen isotope ratios are captured by authigenic carbonates, which form during the spring and summer in response to pH changes associated with primary production. These carbonate minerals (calcite) precipitate in isotopic equilibrium and are deposited on the lakebed where they are preserved. The Shark Lake δ18O record demonstrates a transition from lower to higher average δ18O values from the middle to the late-Holocene at around 4500 yr BP. This is consistent with previous findings of changes in PNA-like atmospheric patterns during the middle Holocene, when a gradual shift from a more negative to a more positive mean state phase of the PNA occurred. This produced enhanced zonal atmospheric circulation in the Pacific Basin that led to a reduction in winter precipitation in northwestern North America and drier conditions in the southwestern part of the continent in the late Holocene relative to the middle Holocene. The Shark Lake δ18O record has a positive, significant correlation with other similar records from the Pacific Northwest, specifically those from Lime Lake (WA) and the OCNM (OR) speleothem, and has a negative, significant correlation with records from the southern Rocky Mountains and eastern North America, namely those from Bison Lake (CO), Cheeseman Lake (NL), Grinnell Lake (NJ), and the Buckeye Creek Cave speleothems (WV). Decadally resolved records are useful for tracking changes in PNA state and its interaction with other related climate oscillations such as the El Niño Southern Oscillation (ENSO) and the associated Pacific Decadal Oscillation (PDO). Open-basin lake records can also be combined with hydrologically closed-basin lake records to reconstruct pluvial and drought periods over the Holocene. The Shark Lake record increases the spatial resolution of mid- to late Holocene hydroclimate climate data in the Rocky Mountains and provides a baseline for natural variability in precipitation seasonality in a hydrologically important region.
A 10-Year Assessment of Equitable Geographic Inclusion in Minnesota's Legacy Amendment
(2021-07) Alfaro, Benjamin D
As a dynamic model for public funding to the arts - and the single largest state-based conservation finance measure to pass in the nation's history - Minnesota's Clean Water, Land and Legacy Amendment dictates annual government spending to environmental, artistic, and cultural causes in an unprecedented method. The Legacy Amendment boasts the largest voter turnout for an issue referendum in Minnesota's history and represents a nationally distinct policy model responsible for more than $3 billion in total dollars designated for the aforementioned purposes from 2009 to 2021. This project interrogates only one of several measurable areas of the policy model, specifically examining the geographic spread of funds over the amendment's first 10 years and using an equity lens to explore the relationship between government spending and the measure of "fairness" as a key criterion for success. Previous research exploring socially equitable public administration has challenged such ambiguous benchmarks for policy goals, instead encouraging more empirical, contextual definitions of how success might be determined. With these critiques in mind, this study lays the groundwork for understanding the Legacy Amendment as a multi-pronged instrument of economic subjectivity by navigating how the relationship between legislative priorities and spending decisions manifested during the first decade of the policy. Initial findings indicate approximately two-thirds of all Legacy funds affected statewide or multi-county causes, demonstrating a broad alignment with policy goals. Despite significant variances in total dollars spent, higher density urban areas and economic development regions demonstrated relatively parallel ratios in their share of Legacy spending per capita. The baseline data collected through this project lends itself to future examination of the Legacy Amendment's other self-described and perceivably benevolent goals.
10.1 Faculty Masthead
(University of Minnesota. Consortium on Law and Values in Health, Environment & the Life Sciences, 2009)
10.1 Student Masthead
(University of Minnesota. Consortium on Law and Values in Health, Environment & the Life Sciences, 2009)
10.2 Faculty Masthead
(University of Minnesota. Consortium on Law and Values in Health, Environment & the Life Sciences, 2009)
10.2 Student Masthead
(University of Minnesota. Consortium on Law and Values in Health, Environment & the Life Sciences, 2009)
10.5 T CRT-MRSI metabolic, spectral and quality maps
(2024-10-01) Marjanska, Malgorzata; Bogner, Wolfgang; Hingerl, Lukas; Strasser, Bernhard; gosia@umn.edu; Marjanska, Malgorzata; University of Minnesota, Center for Magnetic Resonance Research
Magnetic resonance spectroscopy data measured from a brain of a healthy volunteer at 10. 5 tesla. These data show the metabolic maps, CRLB maps and LCModel fits, input data and fitted baseline in nifti-format. The volunteer was measured three different resolutions (4.40 mm³ isotropic, 3.44 mm³ isotropic, and 2.75 mm³ isotropic) using a concentric ring trajectory (CRT) FID-based sequence, reconstructed using a discrete Fourier transform, and fitted with LCModel (for more details, see below). The metabolic maps are in auxilliary units (a.u.) and are not in physical units. All these files can be viewed with freeview of freesurfer 7.1.1. It is being released to allow researchers to fully appreciate these 3D datasets, which are hard to otherwise visualize.
100 in 100: A Learning Tour of 100 Rural Women
(The Regents of the University of Minnesota, 2021-06) Stower, Kathryn
This is a co-publication of the University of Minnesota’s Center for Urban and Regional Affairs (CURA), Northwest Regional Sustainable Development Partnership, and 100 Rural Women. Project funding was provided by the University of Minnesota’s CURA Compact Fund, and the Mary J. Page Community-University Partnership Fund. The Community Assistantship Program (CAP) is a cross-college, cross-campus University of Minnesota initiative coordinated by the Center for Urban and Regional Affairs (CURA) and the Regional Sustainable Development Partnerships (RSDP). The content of this report is the responsibility of the author and is not necessarily endorsed by CAP, CURA, RSDP or the University of Minnesota. The Northwest Regional Sustainable Development Partnership brings together local talent and resources with University of Minnesota knowledge to drive sustainability in agriculture and food systems, tourism and resilient communities, natural resources and clean energy. The Partnerships are part of University of Minnesota Extension. 100 Rural Women serves and supports rural women by identifying, connecting and creating relationships, models of networking, leadership, mentorship and civic engagement.

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