222 research outputs found

    Wildlife linkages: volumes and values of residual timber in riparian zones in eastern Texas

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    In regenerating southern pine, maintenance of riparian zones (RZs) is a major land concession for soil and water protection and wildlife habitat enhancement. However, there are few data quantifying the volume and value of residual timber in such areas. We inventoried merchantable timber in nine RZs of three widths in sapling-class East Texas pine plantations. Present, discounted, and projected volumes and values of residual timber were determined. Average per-acre volumes of narrow, medium, and wide RZs were 337, 1438, and 2542 board feet (Doyle log rule) and 4.6, 8.2, and 7.2 cords, respectively. At US 154.00andUS154.00 and US 57.00 per thousand board feet for pine and hardwood saw timber, respectively, and US 15.00andUS15.00 and US 5.00 per cord for pine and hardwood pulpwood, respectively, average present per-acre values were US 46.41,US46.41, US 209.93 and US 352.75fornarrow,medium,andwideRZs.Interestratesforthegrowthoftreesfrom1981to1989ranged3.7352.75 for narrow, medium, and wide RZs. Interest rates for the growth of trees from 1981 to 1989 ranged 3.7%-23.5% for pine and 2.2%-6.1% for hardwood. For the 1981-1989 discount period, average per-acre net annual equivalents of narrow, medium, and wide RZs were US 4.52, US 20.46,andUS20.46, and US 34.38, respectively. Stumpage values at the time of harvest projected at 7% compound interest for 30 years ranged US 10.66US10.66-US 3547.54 per acre and for 80 years ranged US 313.93US313.93-US 104 499.95 per acre. The impact of these results on wildlife is discusse

    An interpretative phenomenological analysis of men’s and women’s coping strategy selection during early IVF treatment

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    Objectives: To describe the coping strategies that men and women adopted during the early stages of in vitro fertilisation treatment, and explore why and how they selected those strategies. Background: Previous research has identified coping strategies used during fertility treatment and the impact of those strategies on adjustment, but not how and why individuals choose the strategies they did, which is important for understanding coping strategy use as a self-regulatory process. Methods: Three heterosexual couples took part in two or three individual semi-structured interviews over six months, producing fourteen accounts, which were analysed using interpretative phenomenological analysis. Results: The emergent themes were: not dwelling on emotional issues; getting on with treatment; and keeping busy with other things. Participants selected coping strategies in a conscious, deliberate way, by making comparisons with other patients and by drawing on their broader, customary ways of coping. The strategies participants adopted made sense in the context of their long-term goals as well as their short-term treatment objectives. Conclusion: This research shows that for these participants, shorter-term behavioural strategies were informed by longer-term goals, which is consistent with a self-regulatory approach to understanding how people cope with the stress of treatment for infertility.N/

    Oligodendroglial modulation of fast axonal transport in a mouse model of hereditary spastic paraplegia

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    Oligodendrocytes are critical for the development of the plasma membrane and cytoskeleton of the axon. In this paper, we show that fast axonal transport is also dependent on the oligodendrocyte. Using a mouse model of hereditary spastic paraplegia type 2 due to a null mutation of the myelin Plp gene, we find a progressive impairment in fast retrograde and anterograde transport. Increased levels of retrograde motor protein subunits are associated with accumulation of membranous organelles distal to nodal complexes. Using cell transplantation, we show categorically that the axonal phenotype is related to the presence of the overlying Plp null myelin. Our data demonstrate a novel role for oligodendrocytes in the local regulation of axonal function and have implications for the axonal loss associated with secondary progressive multiple sclerosis

    Brief of Tribal Nations and Indian Organizations as Amici Curiae in Support of the Navajo Nation, U.S. Supreme Court Docket No. 21-1484

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    SUMMARY OF ARGUMENT: The Winters Doctrine recognizes and gives effect to the promises made by the United States in treaties, congressionally ratified agreements, and executive orders that Tribal Nations would retain permanent and viable homelands. These promises, made in exchange for the Tribal Nations’ cession of billions of acres of land, paved the way for the non-Indian settlement of the West. Although every tribal homeland is unique, invariably, each requires water to be livable. Applying the canons of construction this Court has developed as part of its federal Indian law jurisprudence, as well as the history and circumstances surrounding the creation of each individual reservation, the Winters Doctrine holds that the United States promised to provide water sufficient to fulfill the purposes for which the reservations were created. Concomitant with the promise to reserve water rights is the corresponding duty to protect and deliver on that promise and avoid rendering those rights meaningless through obstruction, depletion, or diversion to more junior users. In this way, the Winters Doctrine is a pathway for ensuring the United States fulfills its solemn obligations to Tribal Nations. The United States—through both Congress and the Executive—has repeatedly and expressly reaffirmed its understanding of these obligations. Petitioners here articulate no reason why the Lower Colorado River Basin should be treated differently. This Court should once again ensure the United States honors its obligations. In the 115 years since Winters v. United States, the Doctrine solidified into an integral part of the fabric that makes up Western water management. The Winters Doctrine forms the basis for extensive adjudication and settlement of claims by Tribal Nations to water rights. Today, millions of tribal and non-tribal citizens benefit from the certainty provided by the Winters Doctrine

    Ready ... Go: Amplitude of the fMRI Signal Encodes Expectation of Cue Arrival Time

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    What happens when the brain awaits a signal of uncertain arrival time, as when a sprinter waits for the starting pistol? And what happens just after the starting pistol fires? Using functional magnetic resonance imaging (fMRI), we have discovered a novel correlate of temporal expectations in several brain regions, most prominently in the supplementary motor area (SMA). Contrary to expectations, we found little fMRI activity during the waiting period; however, a large signal appears after the “go” signal, the amplitude of which reflects learned expectations about the distribution of possible waiting times. Specifically, the amplitude of the fMRI signal appears to encode a cumulative conditional probability, also known as the cumulative hazard function. The fMRI signal loses its dependence on waiting time in a “countdown” condition in which the arrival time of the go cue is known in advance, suggesting that the signal encodes temporal probabilities rather than simply elapsed time. The dependence of the signal on temporal expectation is present in “no-go” conditions, demonstrating that the effect is not a consequence of motor output. Finally, the encoding is not dependent on modality, operating in the same manner with auditory or visual signals. This finding extends our understanding of the relationship between temporal expectancy and measurable neural signals

    Rational use of antibiotics by community health workers and caregivers for children with suspected pneumonia in Zambia: A cross-sectional mixed methods study

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    Background: Antibiotic resistance is an issue of growing global concern. One key strategy to minimise further development of resistance is the rational use of antibiotics, by providers and patients alike. Through integrated community case management (iCCM), children diagnosed with suspected pneumonia are treated with antibiotics; one component of an essential package to reduce child mortality and increase access to health care for remote populations. Through the use of clinical algorithms, supportive supervision and training, iCCM also offers the opportunity to improve the rational use of antibiotics and limit the spread of resistance in resource-poor contexts. This study provides evidence on antibiotic use by community health workers (CHWs) and caregivers to inform iCCM programmes, safeguarding current treatments whilst maximising access to care. Methods: 1497 CHW consultations were directly observed by non-clinical researchers, with measurement of respiratory rate by CHWs recorded by video. Videos were used to conduct a retrospective reference standard assessment of respiratory rate by experts. Fifty-five caregivers whose children were prescribed a 5-day course of antibiotics for suspected pneumonia were followed up on day six to assess adherence through structured interviews and pill counts. Six focus group discussions and nine in depth interviews were conducted with CHWs and caregivers to supplement quantitative findings. Results: The findings indicate that CHWs adhered to treatment guidelines for 92 % of children seen, prescribing treatment corresponding to their assessment. However, only 65 % of antibiotics prescribed were given for children with experts' confirmed fast breathing pneumonia. Qualitative data indicates that CHWs have a good understanding of pneumonia diagnosis, and although caregivers sometimes applied pressure to receive drugs, CHWs stated that treatment decisions were not influenced. 46 % of caregivers were fully adherent and gave their child the full 5-day course of dispersible amoxicillin. If caregivers who gave treatment for 3 to 5 days were considered, adherence increased to 76 %. Conclusions: CHWs are capable of prescribing treatment corresponding to their assessment of respiratory rate. However, rational use of antibiotics could be strengthened through improved respiratory rate assessment, and better diagnostic tools. Furthermore, a shorter course of dispersible amoxicillin could potentially improve caregiver adherence, reducing risk of resistance and cost

    Reduction of Pavlovian bias in schizophrenia: Enhanced effects in clozapine-administered patients

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    The negative symptoms of schizophrenia (SZ) are associated with a pattern of reinforcement learning (RL) deficits likely related to degraded representations of reward values. However, the RL tasks used to date have required active responses to both reward and punishing stimuli. Pavlovian biases have been shown to affect performance on these tasks through invigoration of action to reward and inhibition of action to punishment, and may be partially responsible for the effects found in patients. Forty-five patients with schizophrenia and 30 demographically-matched controls completed a four-stimulus reinforcement learning task that crossed action ("Go" or "NoGo") and the valence of the optimal outcome (reward or punishment-avoidance), such that all combinations of action and outcome valence were tested. Behaviour was modelled using a six-parameter RL model and EEG was simultaneously recorded. Patients demonstrated a reduction in Pavlovian performance bias that was evident in a reduced Go bias across the full group. In a subset of patients administered clozapine, the reduction in Pavlovian bias was enhanced. The reduction in Pavlovian bias in SZ patients was accompanied by feedback processing differences at the time of the P3a component. The reduced Pavlovian bias in patients is suggested to be due to reduced fidelity in the communication between striatal regions and frontal cortex. It may also partially account for previous findings of poorer "Go-learning" in schizophrenia where "Go" responses or Pavlovian consistent responses are required for optimal performance. An attenuated P3a component dynamic in patients is consistent with a view that deficits in operant learning are due to impairments in adaptively using feedback to update representations of stimulus value
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