• Labyrinth patterns in Magadi (Kenya) cherts: Evidence for early formation from siliceous gels

  Leet, Kennie; Lowenstein, Tim K.; Renaut, Robin W.; Owen, R. Bernhart; Cohen, Andrew; Department of Geosciences, University of Arizona (Geological Society of America, 2021-06-03)

  Sedimentary cherts, with well-preserved microfossils, are known from the Archean to the present, yet their origins remain poorly understood. Lake Magadi, Kenya, has been used as a modern analog system for understanding the origins of nonbiogenic chert. We present evidence for synsedimentary formation of Magadi cherts directly from siliceous gels. Petrographic thin-section analysis and field-emission scanning electron microscopy of cherts from cores drilled in Lake Magadi during the Hominin Sites and Paleolakes Drilling Project in 2014 led to the discovery of two-dimensional branching “labyrinth patterns” in chert, which are a type of fractal “squeeze” pattern formed at air-liquid interfaces. Labyrinth patterns preserved in chert from Lake Magadi cores indicate invasion of air along planes in dewatering gels. These patterns support the precipitation of silica gels in the saline-alkaline Lake Magadi system and syndepositional drying of gels in contact with air as part of chert formation. Recognizing cherts as syndepositional has been critical for our use of them for U-Th dating. Identification of labyrinth patterns in ancient cherts can provide a better understanding of paleoenvironmental and geochemical conditions in the past © 2021 Geological Society of America.
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  Role of Eosinophil Derived TGF-β1 in the Asthmatic Lung

  Lee, James J.; Cohen, Zoe; Neely, Joseph (The University of Arizona., 2016)

  Allergies and associated asthma represent a subset of diseases that have steadily increased in prevalence and severity in the western world. Allergic asthma is an immunological disorder that results in the physiological presentation of wheezing and shortness of breath caused by constriction of lung smooth muscle and narrowing of the airways. These symptoms occur when the lungs are exposed to an allergen. Current studies have found that 8.3% of the United States population has asthma, with figures showing a steady increase each year. While clinical treatment of asthma has been estimated to be $56 billion dollars, there is currently no cure for asthma. As of now, only the symptoms can be treated due to a poorly understood molecular mechanism for the disease. As this disease continues to grow in prevalence, it is critical to understand the underlying causes of the disease in order to develop new treatment options to target these causes rather than symptoms of asthma. Following this point, there have been an increasing amount of publications indicating that eosinophils are a potential effector cell mediating the marked physiological and anatomical changes that this disease brings. Investigation into the role of eosinophils in asthma pathology is needed to understand how this cell type contributes to the classical physiological dysfunction that is seen in allergic asthma cases.
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  Antigen Specific Eosinophil Mediated Nitration

  Lee, James J.; Elfring, Lisa; Neely, Joseph (The University of Arizona., 2016)

  The immune system has two specific branches (i.e., innate immune response and acquired or adaptive immunity) that work together to protect an individual from illness. The innate immune system is the evolutionarily older of the two branches that responds to a wide-array of pathogens with limited target specificity. That is, the innate immune system is capable of destroying pathogens by recognizing common pathogenic moieties or patterns. These immune responses mediate the killing of target pathogens by using an array of methods from engulfing and digesting bacteria to generating reactive molecules to damage larger multi-cellular parasites. The innate immune system is often the first responder to a site of injury or infection and is usually able to successfully target most infections before they become an issue. [excerpt from Introduction]
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  A controlled trial of two mind-body interventions for grief in widows and widowers

  Knowles, Lindsey M; Jovel, Krystal S; Mayer, Candace M; Bottrill, Kenneth C; Kaszniak, Alfred W; Sbarra, David A; Lawrence, Erika E; O'Connor, Mary-Frances; Department of Psychology, University of Arizona (American Psychological Association, 2021)

  Objective: Following bereavement, yearning and grief rumination are repetitive cognitive processes that can lead to disordered grief. Mindfulness training (MT) has been shown to reduce maladaptive repetitive thought. The current quasi-randomized controlled trial examined the feasibility, acceptability, and preliminary efficacy of MT for bereavement-related grief. Method: Ninety-five widow(er)s (Mage = 67.5, 79% women, 98% White) between 6 months to 4 years post-loss were assigned to a 6-week MT intervention or a progressive muscle relaxation (PMR) intervention, or a wait-list condition. Outcome measures were grief severity (Revised Inventory of Complicated Grief), yearning (Yearning in Situations of Loss), rumination (Utrecht Grief Rumination Scale), and decentering (Experiences Questionnaire-Decentering) assessed at baseline, Weeks 2 and 4 of intervention, post-intervention, and 1-month post-intervention. Growth curve analysis examined group differences in rates of improvement in outcomes through follow-up and associations with improvement in grief severity. Results: The MT and PMR groups showed significant rates of decline in grief severity and yearning, though only the PMR group showed a greater rate of decline in grief severity than wait-list. All groups showed significant rates of decline in grief rumination. The PMR and wait-list groups showed significant rates of increase in decentering compared to the MT group. Conclusions: Results support the feasibility and acceptability of MT and PMR for widow(er)s as well as the preliminary efficacy of PMR for improving grief severity in widow(er)s compared to a wait-list control condition. With replication, PMR could be a standalone intervention for non-disordered grief or a component of treatment for disordered grief.
• A lonely dot on the map: Exploring the climate signal in tree-ring density and stable isotopes of clanwilliam cedar, South Africa

  De Mil, Tom; Meko, Matthew; Belmecheri, Soumaya; February, Edmund; Therrell, Matthew; Van den Bulcke, Jan; Trouet, Valerie; Laboratory of Tree-Ring Research, University of Arizona (Elsevier BV, 2021-10)

  Clanwilliam cedar (Widdringtonia cedarbergensis; WICE), a long-lived conifer with distinct tree rings in Cape Province, South Africa, has potential to provide a unique high-resolution climate proxy for southern Africa. However, the climate signal in WICE tree-ring width (TRW) is weak and the dendroclimatic potential of other WICE tree-ring parameters therefore needs to be explored. Here, we investigate the climatic signal in various tree-ring parameters, including TRW, Minimum Density (MND), Maximum Latewood Density (MXD), Maximum Latewood Blue Intensity (MXBI), and stable carbon and oxygen isotopes (δ18O and δ13C) measured in WICE samples collected in 1978. MND was negatively influenced by early spring (October-November) precipitation whereas TRW was positively influenced by spring November-December precipitation. MXD was negatively influenced by autumn (April-May) temperature whereas MXBI was not influenced by temperature. Both MXD and MXBI were negatively influenced by January-March and January-May precipitation respectively. We did not find a significant climate signal in either of the stable isotope time series, which were measured on a limited number of samples. WICE can live to be at least 356 years old and the current TRW chronology extends back to 1564 CE. The development of full-length chronologies of alternative tree-ring parameters, particularly MND, would allow for an annually resolved, multi-century spring precipitation reconstruction for this region in southern Africa, where vulnerability to future climate change is high.

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