1,234 research outputs found

    Evaluating the impacts of the Tennessee master logger program

    Get PDF
    A field evaluation of Best Management Practices was used to determine the effectiveness of the Tennessee Master Logger Program (TMLP). The study was focussed and conducted on non-industrial private forestland (NIPF), and excluded harvests on land owned by forest industry or public forests. Completed logging jobs were scored on 4 possible disturbance areas of timber harvesting: 1) haul roads, 2) skid trails, 3) log decks, and 4) Streamside Management Zones (SMZs). These four scores were added together to yield an overall BMP score. Of 191 randomly chosen observation sites across the state of Tennessee, 38, or 19.9%, were logged by trained Master Loggers. A significant association (p \u3c .05) was found between logger training and overall BMP score using a point biserial correlation. Only 17 of the 627 scores (some sites did not have all 4 areas of the harvest, for example, SMZs are not necessary on sites without streams), or 2.6%, exhibited threats to water quality. Of these 17, Master Loggers were only responsible for 3 water quality threats. Point biserial correlations also indicated that a substantial association (p \u3c .05) existed between harvests completed by Master Loggers and the scores of haul roads, skid trails, log decks, and SMZ grades. This study indicates that those loggers who received training from the TMLP were more likely to implement Best Management Practices during harvesting operations on NIPF than those loggers who did not participate in the Tennessee Master Logger Program

    Soil Compaction and Visual Disturbance Following an Integrated Mechanical Forest Fuel Reduction Operation in Southwest Oregon

    Get PDF
    Most mechanical forest fuel reduction treatments prescribed to extract biomass are performed with existing or modified conventional logging equipment. Treatments that commonly harvest small, non-merchantable trees are often combined with or integrated into commercial thinning operations. Only a limited amount of literature has quantified harvesting system feasibility or environmental effects from such operations. The extra stand travel required to fell and extract small trees may lead to additional soil disturbance. The objective of this study was to assess soil disturbance from an integrated forest harvesting/mechanical forest fuel reduction operation in southwest Oregon, USA. The study was conducted in a fuel reduction thinning of a densely stocked 8.1-hectare (20-acre) mixed conifer stand on gentle terrain. A tracked, swing-boom feller-buncher and two rubber-tired, grapple skidders were used for felling and extracting both non-merchantable and merchantable trees. Visually classified soil disturbance, along with penetration resistance estimates were recorded pre- and post harvesting. Results indicate that the operation did not contribute to either statistically or biologically significant soil disturbance effects, based on an a priori biological reference threshold of 3,000 kPa. A history of multiple harvest entries, low soil moisture, and high initial soil strength conditions contributed to the lack of significant effects. This investigation will aid forest managers in decision making concerning expected soil disturbance effects when prescribing integrated harvesting systems for forest fuel reduction treatments

    The Factorization of 2 and 3 in Cyclic Quartic Fields

    Get PDF
    Due to a theorem of Dedekind, factoring ideals generated by prime numbers in number fields is easily done given that said prime number does not divide the index of the field. In this paper, we determine the prime ideal factorizations of both 2 and 3 in cyclic quartic fields whose index is divisible by one of or both of these primes

    ADIPOR1 is essential for vision and its RPE expression is lost in the Mfrp

    Get PDF
    The knockout (KO) of the adiponectin receptor 1 (AdipoR1) gene causes retinal degeneration. Here we report that ADIPOR1 protein is primarily found in the eye and brain with little expression in other tissues. Further analysis of AdipoR1 KO mice revealed that these animals exhibit early visual system abnormalities and are depleted of RHODOPSIN prior to pronounced photoreceptor death. A KO of AdipoR1 post-development either in photoreceptors or the retinal pigment epithelium (RPE) resulted in decreased expression of retinal proteins, establishing a role for ADIPOR1 in supporting vision in adulthood. Subsequent analysis of the Mfr

    Involvement of Noradrenergic Neurotransmission in the Stress- but not Cocaine-Induced Reinstatement of Extinguished Cocaine-Induced Conditioned Place Preference in Mice: Role for β-2 Adrenergic Receptors

    Get PDF
    The responsiveness of central noradrenergic systems to stressors and cocaine poses norepinephrine as a potential common mechanism through which drug re-exposure and stressful stimuli promote relapse. This study investigated the role of noradrenergic systems in the reinstatement of extinguished cocaine-induced conditioned place preference by cocaine and stress in male C57BL/6 mice. Cocaine- (15 mg/kg, i.p.) induced conditioned place preference was extinguished by repeated exposure to the apparatus in the absence of drug and reestablished by a cocaine challenge (15 mg/kg), exposure to a stressor (6-min forced swim (FS); 20–25°C water), or administration of the α-2 adrenergic receptor (AR) antagonists yohimbine (2 mg/kg, i.p.) or BRL44408 (5, 10 mg/kg, i.p.). To investigate the role of ARs, mice were administered the nonselective β-AR antagonist, propranolol (5, 10 mg/kg, i.p.), the α-1 AR antagonist, prazosin (1, 2 mg/kg, i.p.), or the α-2 AR agonist, clonidine (0.03, 0.3 mg/kg, i.p.) before reinstatement testing. Clonidine, prazosin, and propranolol failed to block cocaine-induced reinstatement. The low (0.03 mg/kg) but not high (0.3 mg/kg) clonidine dose fully blocked FS-induced reinstatement but not reinstatement by yohimbine. Propranolol, but not prazosin, blocked reinstatement by both yohimbine and FS, suggesting the involvement of β-ARs. The β-2 AR antagonist ICI-118551 (1 mg/kg, i.p.), but not the β-1 AR antagonist betaxolol (10 mg/kg, i.p.), also blocked FS-induced reinstatement. These findings suggest that stress-induced reinstatement requires noradrenergic signaling through β-2 ARs and that cocaine-induced reinstatement does not require AR activation, even though stimulation of central noradrenergic neurotransmission is sufficient to reinstate

    Serial expression analysis of breast tumors during neoadjuvant chemotherapy reveals changes in cell cycle and immune pathways associated with recurrence and response

    Get PDF
    Abstract Introduction The molecular biology involving neoadjuvant chemotherapy (NAC) response is poorly understood. To elucidate the impact of NAC on the breast cancer transcriptome and its association with clinical outcome, we analyzed gene expression data derived from serial tumor samples of patients with breast cancer who received NAC in the I-SPY 1 TRIAL. Methods Expression data were collected before treatment (T1), 24–96 hours after initiation of chemotherapy (T2) and at surgery (TS). Expression levels between T1 and T2 (T1 vs. T2; n = 36) and between T1 and TS (T1 vs. TS; n = 39) were compared. Subtype was assigned using the PAM50 gene signature. Differences in early gene expression changes (T2 − T1) between responders and nonresponders, as defined by residual cancer burden, were evaluated. Cox proportional hazards modeling was used to identify genes in residual tumors associated with recurrence-free survival (RFS). Pathway analysis was performed with Ingenuity software. Results When we compared expression profiles at T1 vs. T2 and at T1 vs. TS, we detected significantly altered expression of 150 and 59 transcripts, respectively. We observed notable downregulation of proliferation and immune-related genes at T2. Lower concordance in subtype assignment was observed between T1 and TS (62 %) than between T1 and T2 (75 %). Analysis of early gene expression changes (T2 − T1) revealed that decreased expression of cell cycle inhibitors was associated with poor response. Increased interferon signaling (TS − T1) and high expression of cell proliferation genes in residual tumors (TS) were associated with reduced RFS. Conclusions Serial gene expression analysis revealed candidate immune and proliferation pathways associated with response and recurrence. Larger studies incorporating the approach described here are warranted to identify predictive and prognostic biomarkers in the NAC setting for specific targeted therapies. Clinical trial registration ClinicalTrials.gov identifier: NCT00033397 . Registered 9 Apr 2002

    Modulating Pharmacokinetics, Tumor Uptake and Biodistribution by Engineered Nanoparticles

    Get PDF
    Inorganic nanoparticles provide promising tools for biomedical applications including detection, diagnosis and therapy. While surface properties such as charge are expected to play an important role in their in vivo behavior, very little is known how the surface chemistry of nanoparticles influences their pharmacokinetics, tumor uptake, and biodistribution.Using a family of structurally homologous nanoparticles we have investigated how pharmacological properties including tumor uptake and biodistribution are influenced by surface charge using neutral (TEGOH), zwitterionic (Tzwit), negative (TCOOH) and positive (TTMA) nanoparticles. Nanoparticles were injected into mice (normal and athymic) either in the tail vein or into the peritoneum.Neutral and zwitterionic nanoparticles demonstrated longer circulation time via both i.p. and i.v. administration, whereas negatively and positively charged nanoparticles possessed relatively short half-lives. These pharmacological characteristics were reflected on the tumor uptake and biodistribution of the respective nanoparticles, with enhanced tumor uptake by neutral and zwitterionic nanoparticles via passive targeting

    Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas

    Get PDF
    This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin
    • …
    corecore