Rangelands of the Qinghai-Tibetan plateau (QTP), although sparsely populated and contributing little to China's overall economy, play an important environmental role throughout Asia. They contain ...high biodiversity values and can also potentially provide China with a source of cultural and geographic variety in the future. Chinese government reports paint a gloomy picture, considering vast portions of the QTP degraded and blaming irrational overstocking of livestock as the principal culprit. Global climate change, population increases, and “rodent” damage are also invoked as causes of rangeland degradation. In contrast, some Western observers claim that traditional pastoral practices were sustainable, and identify either previous or more recent state policies as the cause of degradation. Chinese governments at national and provincial levels have initiated a number of sometimes-conflicting and confusing policies aimed, at least nominally, at restoring rangeland productivity. On the basis of a comprehensive literature review, I argue that the extent and magnitude of rangeland degradation on the QTP remains largely unknown because monitoring programs have been subjective and poorly documented. Further, I argue that causes of degradation remain uncertain, often because hypotheses have been articulated too vaguely to test. No phenomena that have been hypothesized as contributing to rangeland degradation on the QTP currently enjoy unequivocal support. Where over-stocking is clearly causing damage, we lack sufficient understanding of current socio-ecological systems to identify ultimate and proximate drivers of pastoralist behavior, and thus policy initiatives aimed at sustainability may well fail.
Choice of variables, climate models and emissions scenarios all influence the results of species distribution models under future climatic conditions. However, an overview of applied studies suggests ...that the uncertainty associated with these factors is not always appropriately incorporated or even considered. We examine the effects of choice of variables, climate models and emissions scenarios can have on future species distribution models using two endangered species: one a short-lived invertebrate species (Ptunarra Brown Butterfly), and the other a long-lived paleo-endemic tree species (King Billy Pine). We show the range in projected distributions that result from different variable selection, climate models and emissions scenarios. The extent to which results are affected by these choices depends on the characteristics of the species modelled, but they all have the potential to substantially alter conclusions about the impacts of climate change. We discuss implications for conservation planning and management, and provide recommendations to conservation practitioners on variable selection and accommodating uncertainty when using future climate projections in species distribution models.
Acute traumatic spinal cord injury results in disability and use of health care resources, yet data on contemporary national trends of traumatic spinal cord injury incidence and etiology are limited.
...To assess trends in acute traumatic spinal cord injury incidence, etiology, mortality, and associated surgical procedures in the United States from 1993 to 2012.
Analysis of survey data from the US Nationwide Inpatient Sample databases for 1993-2012, including a total of 63,109 patients with acute traumatic spinal cord injury.
Age- and sex-stratified incidence of acute traumatic spinal cord injury; trends in etiology and in-hospital mortality of acute traumatic spinal cord injury.
In 1993, the estimated incidence of acute spinal cord injury was 53 cases (95% CI, 52-54 cases) per 1 million persons based on 2659 actual cases. In 2012, the estimated incidence was 54 cases (95% CI, 53-55 cases) per 1 million population based on 3393 cases (average annual percentage change, 0.2%; 95% CI, -0.5% to 0.9%). Incidence rates among the younger male population declined from 1993 to 2012: for age 16 to 24 years, from 144 cases/million (2405 cases) to 87 cases/million (1770 cases) (average annual percentage change, -2.5%; 95% CI, -3.3% to -1.8%); for age 25 to 44 years, from 96 cases/million (3959 cases) to 71 cases/million persons (2930 cases), (average annual percentage change, -1.2%; 95% CI, -2.1% to -0.3%). A high rate of increase was observed in men aged 65 to 74 years (from 84 cases/million in 1993 695 cases to 131 cases/million 1465 cases; average annual percentage change, 2.7%; 95% CI, 2.0%-3.5%). The percentage of spinal cord injury associated with falls increased significantly from 28% (95% CI, 26%-30%) in 1997-2000 to 66% (95% CI, 64%-68%) in 2010-2012 in those aged 65 years or older (P < .001). Although overall in-hospital mortality increased from 6.6% (95% CI, 6.1%-7.0%) in 1993-1996 to 7.5% (95% CI, 7.0%-8.0%) in 2010-2012 (P < .001), mortality decreased significantly from 24.2% (95% CI, 19.7%-28.7%) in 1993-1996 to 20.1% (95% CI, 17.0%-23.2%) in 2010-2012 (P = .003) among persons aged 85 years or older.
Between 1993 and 2012, the incidence rate of acute traumatic spinal cord injury remained relatively stable but, reflecting an increasing population, the total number of cases increased. The largest increase in incidence was observed in older patients, largely associated with an increase in falls, and in-hospital mortality remained high, especially among elderly persons.
Real-world studies have become increasingly important in providing evidence of treatment effectiveness in clinical practice. While randomized clinical trials (RCTs) are the “gold standard” for ...evaluating the safety and efficacy of new therapeutic agents, necessarily strict inclusion and exclusion criteria mean that trial populations are often not representative of the patient populations encountered in clinical practice. Real-world studies may use information from electronic health and claims databases, which provide large datasets from diverse patient populations, and/or may be observational, collecting prospective or retrospective data over a long period of time. They can therefore provide information on the long-term safety, particularly pertaining to rare events, and effectiveness of drugs in large heterogeneous populations, as well as information on utilization patterns and health and economic outcomes. This review focuses on how evidence from real-world studies can be utilized to complement data from RCTs to gain a more complete picture of the advantages and disadvantages of medications as they are used in practice.
Funding
: Sanofi US, Inc.
Bidirectional interactions between astrocytes and neurons have physiological roles in the central nervous system and an altered state or dysfunction of such interactions may be associated with ...neurodegenerative diseases, such as Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS). Astrocytes exert structural, metabolic and functional effects on neurons, which can be either neurotoxic or neuroprotective. Their neurotoxic effect is mediated via the senescence-associated secretory phenotype (SASP) involving pro-inflammatory cytokines (e.g., IL-6), while their neuroprotective effect is attributed to neurotrophic growth factors (e.g., NGF). We here demonstrate that the p53 isoforms Δ133p53 and p53β are expressed in astrocytes and regulate their toxic and protective effects on neurons. Primary human astrocytes undergoing cellular senescence upon serial passaging in vitro showed diminished expression of Δ133p53 and increased p53β, which were attributed to the autophagic degradation and the SRSF3-mediated alternative RNA splicing, respectively. Early-passage astrocytes with Δ133p53 knockdown or p53β overexpression were induced to show SASP and to exert neurotoxicity in co-culture with neurons. Restored expression of Δ133p53 in near-senescent, otherwise neurotoxic astrocytes conferred them with neuroprotective activity through repression of SASP and induction of neurotrophic growth factors. Brain tissues from AD and ALS patients possessed increased numbers of senescent astrocytes and, like senescent astrocytes in vitro, showed decreased Δ133p53 and increased p53β expression, supporting that our in vitro findings recapitulate in vivo pathology of these neurodegenerative diseases. Our finding that Δ133p53 enhances the neuroprotective function of aged and senescent astrocytes suggests that the p53 isoforms and their regulatory mechanisms are potential targets for therapeutic intervention in neurodegenerative diseases.
The rise of inorganic–biological hybrid organisms for solar-to-chemical production has spurred mechanistic investigations into the dynamics of the biotic–abiotic interface to drive the development of ...next-generation systems. The model system, Moorella thermoacetica– cadmium sulfide (CdS), combines an inorganic semiconductor nanoparticle light harvester with an acetogenic bacterium to drive the photosynthetic reduction of CO₂ to acetic acid with high efficiency. In this work, we report insights into this unique electrotrophic behavior and propose a charge-transfer mechanism from CdS to M. thermoacetica. Transient absorption (TA) spectroscopy revealed that photoexcited electron transfer rates increase with increasing hydrogenase (H₂ase) enzyme activity. On the same time scale as the TA spectroscopy, time-resolved infrared (TRIR) spectroscopy showed spectral changes in the 1,700–1,900-cm−1 spectral region. The quantum efficiency of this system for photosynthetic acetic acid generation also increased with increasing H₂ase activity and shorter carrier lifetimes when averaged over the first 24 h of photosynthesis. However, within the initial 3 h of photosynthesis, the rate followed an opposite trend: The bacteria with the lowest H₂ase activity photosynthesized acetic acid the fastest. These results suggest a two-pathway mechanism: a high quantum efficiency charge-transfer pathway to H₂ase generating H₂ as a molecular intermediate that dominates at long time scales (24 h), and a direct energy-transducing enzymatic pathway responsible for acetic acid production at short time scales (3 h). This work represents a promising platform to utilize conventional spectroscopic methodology to extract insights from more complex biotic–abiotic hybrid systems.
A central challenge in developing quantum computers and long-range quantum networks is the distribution of entanglement across many individually controllable qubits
. Colour centres in diamond have ...emerged as leading solid-state 'artificial atom' qubits
because they enable on-demand remote entanglement
, coherent control of over ten ancillae qubits with minute-long coherence times
and memory-enhanced quantum communication
. A critical next step is to integrate large numbers of artificial atoms with photonic architectures to enable large-scale quantum information processing systems. So far, these efforts have been stymied by qubit inhomogeneities, low device yield and complex device requirements. Here we introduce a process for the high-yield heterogeneous integration of 'quantum microchiplets'-diamond waveguide arrays containing highly coherent colour centres-on a photonic integrated circuit (PIC). We use this process to realize a 128-channel, defect-free array of germanium-vacancy and silicon-vacancy colour centres in an aluminium nitride PIC. Photoluminescence spectroscopy reveals long-term, stable and narrow average optical linewidths of 54 megahertz (146 megahertz) for germanium-vacancy (silicon-vacancy) emitters, close to the lifetime-limited linewidth of 32 megahertz (93 megahertz). We show that inhomogeneities of individual colour centre optical transitions can be compensated in situ by integrated tuning over 50 gigahertz without linewidth degradation. The ability to assemble large numbers of nearly indistinguishable and tunable artificial atoms into phase-stable PICs marks a key step towards multiplexed quantum repeaters
and general-purpose quantum processors
.
Asian Monsoon rainfall supports the livelihood of billions of people, yet the relative importance of different drivers remains an issue of great debate. Here, we present 30 million-year model-based ...reconstructions of Indian summer monsoon and South East Asian monsoon rainfall at millennial resolution. We show that precession is the dominant direct driver of orbital variability, although variability on obliquity timescales is driven through the ice sheets. Orographic development dominated the evolution of the South East Asian monsoon, but Indian summer monsoon evolution involved a complex mix of contributions from orography (39%), precession (25%), atmospheric CO
(21%), ice-sheet state (5%) and ocean gateways (5%). Prior to 15 Ma, the Indian summer monsoon was broadly stable, albeit with substantial orbital variability. From 15 Ma to 5 Ma, strengthening was driven by a combination of orography and glaciation, while closure of the Panama gateway provided the prerequisite for the modern Indian summer monsoon state through a strengthened Atlantic meridional overturning circulation.
Background. Lower muscle mass has been correlated with poor physical function; however, no studies have examined this relationship prospectively. This study aims to investigate whether low muscle ...mass, low muscle strength, and greater fat infiltration into the muscle predict incident mobility limitation. Methods. Our study cohort included 3075 well-functioning black and white men and women aged 70–79 years participating in the Health, Aging, and Body Composition study. Participants were followed for 2.5 years. Muscle cross-sectional area and muscle tissue attenuation (a measure of fat infiltration) were measured by computed tomography at the mid-thigh, and knee extensor strength by using a KinCom dynamometer. Incident mobility limitation was defined as two consecutive self-reports of any difficulty walking one-quarter mile or climbing 10 steps. Results. Mobility limitations were developed by 22.3% of the men and by 31.8% of the women. Cox's proportional hazards models, adjusting for demographic, lifestyle, and health factors, showed a hazard ratio of 1.90 95% confidence interval (CI), 1.27–2.84 in men and 1.68 (95% CI, 1.23–2.31) in women for the lowest compared to the highest quartile of muscle area (p <.01 for trend). Results for muscle strength were 2.02 (95% CI, 1.39–2.94) and 1.91 (95% CI, 1.41–2.58), p <.001 trend, and for muscle attenuation were 1.91 (95% CI, 1.31–2.83) and 1.68 (95% CI, 1.20–2.35), p <.01 for trend. When included in one model, only muscle attenuation and muscle strength independently predicted mobility limitation (p <.05). Among men and women, associations were similar for blacks and whites. Conclusion. Lower muscle mass (smaller cross-sectional thigh muscle area), greater fat infiltration into the muscle, and lower knee extensor muscle strength are associated with increased risk of mobility loss in older men and women. The association between low muscle mass and functional decline seems to be a function of underlying muscle strength.
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