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Diamond D.M.,University of South Florida | Hama R.,Japan Institute of Pharmacovigilance | Hamazaki T.,University of Toyama | Hammarskjold B.,Stromstad Academy | And 13 more authors.
BMJ Open | Year: 2016

It is well known that total cholesterol becomes less of a risk factor or not at all for all-cause and cardiovascular (CV) mortality with increasing age, but as little is known as to whether low-density lipoprotein cholesterol (LDL-C), one component of total cholesterol, is associated with mortality in the elderly, we decided to investigate this issue. Setting, participants and outcome measures: We sought PubMed for cohort studies, where LDL-C had been investigated as a risk factor for all-cause and/or CV mortality in individuals ≥ 60 years from the general population. Results: We identified 19 cohort studies including 30 cohorts with a total of 68 094 elderly people, where all-cause mortality was recorded in 28 cohorts and CV mortality in 9 cohorts. Inverse association between allcause mortality and LDL-C was seen in 16 cohorts (in 14 with statistical significance) representing 92% of the number of participants, where this association was recorded. In the rest, no association was found. In two cohorts, CV mortality was highest in the lowest LDL-C quartile and with statistical significance; in seven cohorts, no association was found. Conclusions: High LDL-C is inversely associated with mortality in most people over 60 years. This finding is inconsistent with the cholesterol hypothesis (ie, that cholesterol, particularly LDL-C, is inherently atherogenic). Since elderly people with high LDL-C live as long or longer than those with low LDL-C, our analysis provides reason to question the validity of the cholesterol hypothesis. Moreover, our study provides the rationale for a re-evaluation of guidelines recommending pharmacological reduction of LDL-C in the elderly as a component of cardiovascular disease prevention strategies. © Published by the BMJ Publishing Group Limited.

Houlsby N.M.T.,Google | Blei D.M.,Colombia University
Advances in Neural Information Processing Systems | Year: 2014

Stochastic variational inference (SVI) uses stochastic optimization to scale up Bayesian computation to massive data. We present an alternative perspective on SVI as approximate parallel coordinate ascent. SVI trades-off bias and variance to step close to the unknown true coordinate optimum given by batch variational Bayes (VB). We define a model to automate this process. The model infers the location of the next VB optimum from a sequence of noisy realizations. As a consequence of this construction, we update the variational parameters using Bayes rule, rather than a hand-crafted optimization schedule. When our model is a Kalman filter this procedure can recover the original SVI algorithm and SVI with adaptive steps. We may also encode additional assumptions in the model, such as heavy-tailed noise. By doing so, our algorithm outperforms the original SVI schedule and a state-of-the-art adaptive SVI algorithm in two diverse domains.

Edwards D.P.,Princeton University | Edwards D.P.,James Cook University | Woodcock P.,University of Leeds | Edwards F.A.,University of Leeds | And 5 more authors.
Ecological Applications | Year: 2012

A key driver of rain forest degradation is rampant commercial logging. Reduced-impact logging (RIL) techniques dramatically reduce residual damage to vegetation and soils, and they enhance the long-term economic viability of timber operations when compared to conventionally managed logging enterprises. Consequently, the application of RIL is increasing across the tropics, yet our knowledge of the potential for RIL also to reduce the negative impacts of logging on biodiversity is minimal. We compare the impacts of RIL on birds, leaf-litter ants, and dung beetles during a second logging rotation in Sabah, Borneo, with the impacts of conventional logging (CL) as well as with primary (unlogged) forest. Our study took place 1-8 years after the cessation of logging. The species richness and composition of RIL vs. CL forests were very similar for each taxonomic group. Both RIL and CL differed significantly from unlogged forests in terms of bird and ant species composition (although both retained a large number of the species found in unlogged forests), whereas the composition of dung beetle communities did not differ significantly among forest types. Our results show little difference in biodiversity between RIL and CL over the short term. However, biodiversity benefits from RIL may accrue over longer time periods after the cessation of logging. We highlight a severe lack of studies investigating this possibility. Moreover, if RIL increases the economic value of selectively logged forests (e.g., via REDD, a United Nations program: Reducing Emissions from Deforestation and Forest Degradation in Developing Countries), it could help prevent them from being converted to agricultural plantations, which results in a tremendous loss of biodiversity. © 2012 by the Ecological Society of America.

Parekh M.,Colombia University | Tolessa T.B.,St Paul Millennium Medical College | Sherman C.B.,Brown University | Ethel J.C.,Brown University | Schluger N.W.,Colombia University
Ethiopian Medical Journal | Year: 2015

Background: Pulmonary tuberculosis (PTB) is one of the most common infectious diseases worldwide, and contributes significantly to morbidity and mortality in developing countries. Despite availability of effective treatment, a significant number of patients suffer from permanent lung damage, which predisposes patients to numerous pulmonary complications. Objective: To assess chronic sequelae of patients treated for PTB in a chest clinic at Tikur Anbessa Hospital Methods: This was a retrospective, cross-sectional analysis of patients registered in a clinical database at the chest clinic of Tikur Anbessa specialized Hospital between January and December 2013. Patients with a history of pulmonary tuberculosis treatment were identified and included in the analysis. Results: Among all patients having follow-up at the chest clinic of TASH during the study period, 134 (18.5%) presented with chronic pulmonary complications of TB. Seventy two patients (54%) were male, and the mean and median ages were 40 and 37 years, respectively. Of the study population, 83 (61.9%) patients had clinically significant parenchymal scarring and fibrosis, 40 (29.9%) had bronchiectasis, 5(3.7%) had Aspergilloma, 4(3%) had granuloma/calcification, one patient (0.7%) had pleural thickening, and one patient (0.7%) underwent pneumonectomy during the study period. Conclusions: Fibrosis and bronchiectasis were the most common pulmonary complications of tuberculosis among patients encountered at the TASH chest clinic during the study period. This demonstrates the impact of pulmonary tuberculosis is beyond management of active disease.

Bruner E.,National Research Center sobre la Evolucion Humana | Grimaud-Herve D.,French Natural History Museum | Wu X.,CAS Institute of Vertebrate Paleontology and Paleoanthropology | de la Cuetara J.M.,Autonomous University of Madrid | Holloway R.,Colombia University
Quaternary International | Year: 2015

The taxonomic debate on the phylogenetic coherence of Homo erectus as a widespread intercontinental species is constantly put forward, without major agreements. Differences between the African and Asian fossil record as well as differences between the Chinese and Indonesian groups (or even within these two regions) have frequently been used to propose splitting taxonomical alternatives. In this paper, we analyze the endocranial variation of African and Asian specimens belonging to the hypodigm of H. erectus sensu lato, to assess whether or not these groups can be characterized in terms of traditional endocranial metrics. According to the basic endocast proportions, the three geographic groups largely overlap in their phenotypic distribution and morphological patterns. The morphological affinity or differences among the specimens are largely based on brain size. As already evidenced by using other cranial features, traditional paleoneurological metrics cannot distinguish possible independent groups or trends within the Afro-Asiatic H. erectus hypodigm. Endocranial features and variability are discussed as to provide a general perspective on the paleoneurological traits of this taxon. © 2014 Elsevier Ltd and INQUA.

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