666 research outputs found

    Multi‐scale heterogeneity in vegetation and soil carbon in exurban residential land of southeastern Michigan, USA

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    Exurban residential land (one housing unit per 0.2–16.2 ha) is growing in importance as a human‐dominated land use. Carbon storage in the soils and vegetation of exurban land is poorly known, as are the effects on C storage of choices made by developers and residents. We studied C storage in exurban yards in southeastern Michigan, USA, across a range of parcel sizes and different types of neighborhoods. We divided each residential parcel into ecological zones (EZ) characterized by vegetation, soil, and human behavior such as mowing, irrigation, and raking. We found a heterogeneous mixture of trees and shrubs, turfgrasses, mulched gardens, old‐field vegetation, and impervious surfaces. The most extensive zone type was turfgrass with sparse woody vegetation (mean 26% of parcel area), followed by dense woody vegetation (mean 21% of parcel area). Areas of turfgrass with sparse woody vegetation had trees in larger size classes (> 50 cm dbh) than did areas of dense woody vegetation. Using aerial photointerpretation, we scaled up C storage to neighborhoods. Varying C storage by neighborhood type resulted from differences in impervious area (8–26% of parcel area) and area of dense woody vegetation (11–28%). Averaged and multiplied across areas in differing neighborhood types, exurban residential land contained 5240 ± 865 g C/m2 in vegetation, highly sensitive to large trees, and 13 800 ± 1290 g C/m2 in soils (based on a combined sampling and modeling approach). These contents are greater than for agricultural land in the region, but lower than for mature forest stands. Compared with mature forests, exurban land contained more shrubs and less downed woody debris and it had similar tree size‐class distributions up to 40 cm dbh but far fewer trees in larger size classes. If the trees continue to grow, exurban residential land could sequester additional C for decades. Patterns and processes of C storage in exurban residential land were driven by land management practices that affect soil and vegetation, reflecting the choices of designers, developers, and residents. This study provides an example of human‐mediated C storage in a coupled human–natural system.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/122437/1/eap1313.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/122437/2/eap1313_am.pd

    Recent breast cancer incidence trends according to hormone therapy use: the California Teachers Study cohort

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    Abstract Introduction Recent, international declines in breast cancer incidence are unprecedented, and the causes remain controversial. Few data sources can address breast cancer incidence trends according to pertinent characteristics like hormone therapy use history. Methods We used the prospective California Teachers Study to evaluate changes in self-reported use of menopausal hormone therapy (HT) between 1995 to 1996 and 2005 to 2006 and age-adjusted breast cancer incidence among 74,647 participants aged 50 years or older. Breast cancer occurrence was determined by linkage with the California Cancer Registry. Results During 517,286 woman years of follow up, 565 in situ and 2,668 invasive breast cancers were diagnosed. In situ breast cancer incidence rates in this population did not change significantly from 2000 to 2002 to 2003 to 2005, whereas rates of invasive breast cancer declined significantly by 26.0% from 528.0 (95% confidence intervals (CI) = 491.1, 564.9) per 100,000 women in 2000 to 2002 to 390.6 (95% CI = 355.6, 425.7) in 2003 to 2005. The decline in invasive breast cancer incidence rates was restricted to estrogen receptor-positive tumors. In 1996 to 1999 and 2000 to 2002 invasive breast cancer incidence was higher for women who reported current HT use especially estrogen-progestin (EP) use at baseline than for never or past users; but by 2003 to 2005 rates were comparable between these groups. For women who were taking EP in 2001 to 2002,75% of whom had stopped use by 2005 to 2006, incidence had declined 30.6% by 2003 to 2005 (P = 0.001); whereas incidence did not change significantly for those who never took HT (P = 0.33). Conclusions Few data resources can examine prospectively individual HT use and breast cancer diagnosis. Stable in situ breast cancer rates imply consistent levels of screening and suggest recent declines in invasive breast cancer to be explained predominantly by changes in HT use

    Physicians’ Perspectives on Prescribing Benzodiazepines for Older Adults: A Qualitative Study

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    BACKGROUND: There is a continued high prevalence of benzodiazepine use by older community-residing adults and of their continued prescription by practitioners, despite well known adverse effects and the availability of safer, effective alternatives. OBJECTIVES: To understand factors influencing chronic use of benzodiazepines in older adults. DESIGN: Qualitative study, semistructured interviews with physicians. PARTICIPANTS: Thirty-three practicing primary care physicians around Philadelphia. APPROACH: Qualitative interviews were audiotaped, transcribed, and entered into a qualitative software program. A multidisciplinary team coded transcripts and developed themes. RESULTS: Physicians generally endorsed benzodiazepines as effective treatment for anxiety, citing quick action and strong patient satisfaction. The use of benzodiazepines in older adults was not seen to be problematic because they did not show drug-seeking or escalating dose behavior suggesting addiction. Physicians minimized other risks of benzodiazepines and did not view monitoring or restricting renewal of prescriptions as an important clinical focus relative to higher-priority medical issues. Many physicians expressed skepticism about risks of continued use and considerable pessimism in the successful taper/discontinuation in older patients with long-term use and prior failed attempts. Physicians also anticipated patient resistance to any such efforts, including switching physicians. CONCLUSIONS: Primary care physicians are averse to addressing the public health problem of benzodiazepine overuse in the elderly. Their attitudes generally conflict with practice guidelines and they complain of a lack of training in constructive strategies to address this problem. A 2-pronged effort should focus on increasing skill level and preventing new cases of benzodiazepine dependency through improved patient education and vigilant monitoring of prescription renewal

    Description of the attachment geometry of the anteromedial and posterolateral bundles of the ACL from arthroscopic perspective for anatomical tunnel placement

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    The anterior cruciate ligament (ACL) consists of an anteromedial bundle (AMB) and a posterolateral bundle (PLB). A reconstruction restoring the functional two-bundled nature should be able to approximate normal ACL function better than the most commonly used single-bundle reconstructions. Accurate tunnel positioning is important, but difficult. The purpose of this study was to provide a geometric description of the centre of the attachments relative to arthroscopically visible landmarks. The AMB and PLB attachment sites in 35 dissected cadaver knees were measured with a 3D system, as were anatomical landmarks of femur and tibia. At the femur, the mean ACL centre is positioned 7.9 ± 1.4 mm (mean ± 1 SD) shallow, along the notch roof, from the most lateral over-the-top position at the posterior edge of the intercondylar notch and from that point 4.0 ± 1.3 mm from the notch roof, low on the surface of the lateral condyle wall. The mean AMB centre is at 7.2 ± 1.8 and 1.4 ± 1.7 mm, and the mean PLB centre at 8.8 ± 1.6 and 6.7 ± 2.0 mm. At the tibia, the mean ACL centre is positioned 5.1 ± 1.7 mm lateral of the medial tibial spine and from that point 9.8 ± 2.1 mm anterior. The mean AMB centre is at 3.0 ± 1.6 and 9.4 ± 2.2 mm, and the mean PLB centre at 7.2 ± 1.8 and 10.1 ± 2.1 mm. The ACL attachment geometry is well defined relative to arthroscopically visible landmarks with respect to the AMB and PLB. With simple guidelines for the surgeon, the attachments centres can be found during arthroscopic single-bundle or double-bundle reconstructions

    Impact of a workplace 'sit less, move more' program on efficiency-related outcomes of office employees.

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    BACKGROUND: Few studies have examined the impact of 'sit less, move more' interventions on workplace performance. This study assessed the short and mid-term impacts of and patterns of change within, a 19-week workplace web-based intervention (Walk@WorkSpain; W@WS; 2010-11) on employees´ presenteeism, mental well-being and lost work performance. METHODS: A site randomised control trial recruited employees at six Spanish university campuses (n = 264; 42 ± 10 years; 171 female), assigned by worksite and campus to an Intervention (IG; used W@WS; n = 129; 87 female) or an active Comparison group (A-CG; pedometer, paper diary and self-reported sitting time; n = 135; 84 female). A linear mixed model assessed changes between the baseline, ramping (8 weeks), maintenance (11 weeks) and follow-up (two months) phases for the IG versus A-CG on (i) % of lost work productivity (Work Limitations Questionnaire; WLQ); (ii) three scales for presenteeism (WLQ) assessing difficulty meeting scheduling demands (Time), performing cognitive and inter-personal tasks (Mental-Interpersonal) and decrements in meeting the quantity, quality and timeliness of completed work (Output); and (iii) mental well-being (Warwick-Edinburgh Mental Well-being Scale). T-tests assessed differences between groups for changes on the main outcomes. In the IG, a multivariate logistic regression model identified patterns of response according to baseline socio-demographic variables, physical activity and sitting time. RESULTS: There was a significant 2 (group) × 2 (program time points) interaction for the Time (F [3]=8.69, p = 0.005), Mental-Interpersonal (F [3]=10.01, p = 0.0185), Output scales for presenteeism (F [3]=8.56, p = 0.0357), and for % of lost work performance (F [3]=10.31, p = 0.0161). Presenteeism and lost performance rose significantly in both groups across all study time points; after baseline performance was consistently better in the IG than in the A-CG. Better performance was linked to employees being more active (Time, p = 0.041) and younger (Mental-interpersonal, p = 0.057; Output, p = 0.017). Higher total sitting time during nonworking days (Mental-interpersonal, p = 0.019) and lower sitting time during workdays (WLQ Index, p = 0.013) also improved performance. CONCLUSION: Versus an active comparison condition, a 'sit less, move more` workplace intervention effectively reduced an array of markers of lost workday productivity. TRIAL REGISTRATION: NCT02960750 ; Date of registration: 07/11/2016

    Circulating Levels of Adiponectin, Leptin, Fetuin-A and Retinol-Binding Protein in Patients with Tuberculosis: Markers of Metabolism and Inflammation

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    BACKGROUND: Wasting is known as a prominent feature of tuberculosis (TB). To monitor the disease state, markers of metabolism and inflammation are potentially useful. We thus analyzed two major adipokines, adiponectin and leptin, and two other metabolic markers, fetuin-A and retinol-binding protein 4 (RBP4). METHODS: The plasma levels of these markers were measured using enzyme-linked immunosorbent assays in 84 apparently healthy individuals (=no-symptom group) and 46 patients with active pulmonary TB around the time of treatment, including at the midpoint evaluation (=active-disease group) and compared them with body mass index (BMI), C-reactive protein (CRP), chest radiographs and TB-antigen specific response by interferon-γ release assay (IGRA). RESULTS: In the no-symptom group, adiponectin and leptin showed negative and positive correlation with BMI respectively. In the active-disease group, at the time of diagnosis, leptin, fetuin-A and RBP4 levels were lower than in the no-symptom group [adjusted means 2.01 versus 4.50 ng/ml, P<0.0001; 185.58 versus 252.27 µg/ml, P<0.0001; 23.88 versus 43.79 µg/ml, P<0.0001, respectively]. High adiponectin and low leptin levels were associated with large infiltrates on chest radiographs even after adjustment for BMI and other covariates (P=0.0033 and P=0.0020). During treatment, adiponectin levels increased further and then decreased. Leptin levels remained low. Initial low levels of fetuin-A and RBP4 almost returned to the normal reference range in concert with reduced CRP. CONCLUSIONS: Our data and recent literature suggest that low fat store and underlying inflammation may regulate these metabolic markers in TB in a different way. Decreased leptin, increased adiponectin, or this ratio may be a promising marker for severity of the disease independent of BMI. We should further investigate pathological roles of the balance between these adipokines

    Pregnancy-related factors and the risk of breast carcinoma in situ and invasive breast cancer among postmenopausal women in the California Teachers Study cohort

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    Abstract Introduction Although pregnancy-related factors such as nulliparity and late age at first full-term pregnancy are well-established risk factors for invasive breast cancer, the roles of these factors in the natural history of breast cancer development remain unclear. Methods Among 52,464 postmenopausal women participating in the California Teachers Study (CTS), 624 were diagnosed with breast carcinoma in situ (CIS) and 2,828 with invasive breast cancer between 1995 and 2007. Multivariable Cox proportional hazards regression methods were used to estimate relative risks associated with parity, age at first full-term pregnancy, breastfeeding, nausea or vomiting during pregnancy, and preeclampsia. Results Compared with never-pregnant women, an increasing number of full-term pregnancies was associated with greater risk reduction for both breast CIS and invasive breast cancer (both P trend &lt; 0.01). Women having four or more full-term pregnancies had a 31% lower breast CIS risk (RR = 0.69, 95% CI = 0.51 to 0.93) and 18% lower invasive breast cancer risk (RR = 0.82, 95% CI = 0.72 to 0.94). Parous women whose first full-term pregnancy occurred at age 35 years or later had a 118% greater risk for breast CIS (RR = 2.18, 95% CI = 1.36 to 3.49) and 27% greater risk for invasive breast cancer (RR = 1.27, 95% CI = 0.99 to 1.65) than those whose first full-term pregnancy occurred before age 21 years. Furthermore, parity was negatively associated with the risk of estrogen receptor-positive (ER+) or ER+/progesterone receptor-positive (PR+) while age at first full-term pregnancy was positively associated with the risk of ER+ or ER+/PR+ invasive breast cancer. Neither of these factors was statistically significantly associated with the risk of ER-negative (ER-) or ER-/PR- invasive breast cancer, tests for heterogeneity between subtypes did not reach statistical significance. No clear associations were detected for other pregnancy-related factors. Conclusions These results provide some epidemiologic evidence that parity and age at first full-term pregnancy are involved in the development of breast cancer among postmenopausal women. The role of these factors in risk of in situ versus invasive, and hormone receptor-positive versus -negative breast cancer merits further exploration

    Introduction: Toward an Engaged Feminist Heritage Praxis

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    We advocate a feminist approach to archaeological heritage work in order to transform heritage practice and the production of archaeological knowledge. We use an engaged feminist standpoint and situate intersubjectivity and intersectionality as critical components of this practice. An engaged feminist approach to heritage work allows the discipline to consider women’s, men’s, and gender non-conforming persons’ positions in the field, to reveal their contributions, to develop critical pedagogical approaches, and to rethink forms of representation. Throughout, we emphasize the intellectual labor of women of color, queer and gender non-conforming persons, and early white feminists in archaeology

    Streptococcus pneumoniae Serotype 1 Capsular Polysaccharide Induces CD8+CD28− Regulatory T Lymphocytes by TCR Crosslinking

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    Zwitterionic capsular polysaccharides (ZPS) of commensal bacteria are characterized by having both positive and negative charged substituents on each repeating unit of a highly repetitive structure that has an α-helix configuration. In this paper we look at the immune response of CD8+ T cells to ZPSs. Intraperitoneal application of the ZPS Sp1 from Streptococcus pneumoniae serotype 1 induces CD8+CD28− T cells in the spleen and peritoneal cavity of WT mice. However, chemically modified Sp1 (mSp1) without the positive charge and resembling common negatively charged polysaccharides fails to induce CD8+CD28− T lymphocytes. The Sp1-induced CD8+CD28− T lymphocytes are CD122lowCTLA-4+CD39+. They synthesize IL-10 and TGF-β. The Sp1-induced CD8+CD28− T cells exhibit immunosuppressive properties on CD4+ T cells in vivo and in vitro. Experimental approaches to elucidate the mechanism of CD8+ T cell activation by Sp1 demonstrate in a dimeric MHC class I-Ig model that Sp1 induces CD8+ T cell activation by enhancing crosslinking of TCR. The expansion of CD8+CD28− T cells is independent, of direct antigen-presenting cell/T cell contact and, to the specificity of the T cell receptor (TCR). In CD8+CD28− T cells, Sp1 enhances Zap-70 phosphorylation and increasingly involves NF-κB which ultimately results in protection versus apoptosis and cell death and promotes survival and accumulation of the CD8+CD28− population. This is the first description of a naturally occurring bacterial antigen that is able to induce suppressive CD8+CD28− T lymphocytes in vivo and in vitro. The underlying mechanism of CD8+ T cell activation appears to rely on enhanced TCR crosslinking. The data provides evidence that ZPS of commensal bacteria play an important role in peripheral tolerance mechanisms and the maintenance of the homeostasis of the immune system
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