LLukas22/scidocs huggingface dataset:
Sample size estimation and statistical power analyses

The concept of sample size and statistical power estimation is now something that Optometrists that want to perform research, whether it be in practice or in an academic institution, cannot simply hide away from. Ethics committees, journal editors and grant awarding bodies are now increasingly requesting that all research be backed up with sample size and statistical power estimation in order to justify any study and its !ndings.1 This article presents a step-by-step guide of the process for determining sample size and statistical power. It builds on statistical concepts presented in earlier articles in Optometry Today by Richard Armstrong and Frank Eperjesi.2-7
A Versatile Memristor Model With Nonlinear Dopant Kinetics

The need for reliable models that take into account the nonlinear kinetics of dopants is nowadays of paramount importance, particularly with the physical dimensions of electron devices shrinking to the deep nanoscale range and the development of emerging nanoionic systems such as the memristor. In this paper, we present a novel nonlinear dopant drift model that resolves the boundary issues existing in previously reported models that can be easily adjusted to match the dynamics of distinct memristive elements. With the aid of this model, we examine switching mechanisms, current-voltage characteristics, and the collective ion transport in two terminal memristive devices, providing new insights on memristive behavior.
Effect of mechanical ventilator weaning protocols on respiratory outcomes in infants and children: a randomized controlled trial.

CONTEXT
Ventilator management protocols shorten the time required to wean adult patients from mechanical ventilation. The efficacy of such weaning protocols among children has not been studied.


OBJECTIVE
To evaluate whether weaning protocols are superior to standard care (no defined protocol) for infants and children with acute illnesses requiring mechanical ventilator support and whether a volume support weaning protocol using continuous automated adjustment of pressure support by the ventilator (ie, VSV) is superior to manual adjustment of pressure support by clinicians (ie, PSV).


DESIGN AND SETTING
Randomized controlled trial conducted in the pediatric intensive care units of 10 children's hospitals across North America from November 1999 through April 2001.


PATIENTS
One hundred eighty-two spontaneously breathing children (<18 years old) who had been receiving ventilator support for more than 24 hours and who failed a test for extubation readiness on minimal pressure support.


INTERVENTIONS
Patients were randomized to a PSV protocol (n = 62), VSV protocol (n = 60), or no protocol (n = 60).


MAIN OUTCOME MEASURES
Duration of weaning time (from randomization to successful extubation); extubation failure (any invasive or noninvasive ventilator support within 48 hours of extubation).


RESULTS
Extubation failure rates were not significantly different for PSV (15%), VSV (24%), and no protocol (17%) (P =.44). Among weaning successes, median duration of weaning was not significantly different for PSV (1.6 days), VSV (1.8 days), and no protocol (2.0 days) (P =.75). Male children more frequently failed extubation (odds ratio, 7.86; 95% confidence interval, 2.36-26.2; P<.001). Increased sedative use in the first 24 hours of weaning predicted extubation failure (P =.04) and, among extubation successes, duration of weaning (P<.001).


CONCLUSIONS
In contrast with adult patients, the majority of children are weaned from mechanical ventilator support in 2 days or less. Weaning protocols did not significantly shorten this brief duration of weaning.
Design of triplexer combiners for base stations of mobile communications

This work presents a design technique for a class of combining networks used in base stations for mobile communications; the considered network is a triplexer composed by three high selectivity filters presenting arbitrary transmission zeros (both complex and pure imaginary), which are connected at the input port through a suitable 4-port junction. A technique for the design of this combining network is here proposed, which extends a previous approach used for duplexer networks [1]. The design consists in a procedure for the evaluation of the characteristic polynomials of the three composing filters (defined in a normalized frequency domain), once the input junction topology and the transmission zeros of the filters have been assigned. The network synthesized from the characteristic polynomials presents the same reflection zeros of the three filters synthesized separated from the triplexer with an equiripple response in their respective passband; in this way the overall synthesized triplexer presents a quasi-equiripple response in the three passbands. The proposed design approach has been verified through a fabricated prototype, whose measured performance is in good agreement with the expected response obtained from the synthesized network.
Precision Medicine in Patients With Resistant Hypertension and Obstructive Sleep Apnea: Blood Pressure Response to Continuous Positive Airway Pressure Treatment.

BACKGROUND
In patients with resistant hypertension (RH) and obstructive sleep apnea (OSA), the blood pressure response to continuous positive airway pressure (CPAP) treatment is highly variable and could be associated with differential micro-ribonucleic acid (miRNA) profiles. Currently, no available methods exist to identify patients who will respond favorably to CPAP treatment.


OBJECTIVES
The aim of this study was to identify plasma miRNA profiles that predict blood pressure responses to CPAP treatment.


METHODS
Cardiovascular system-focused circulating miRNA expression was evaluated in plasma samples using an 84-miRNA array among patients with RH and OSA at baseline and after 3 months of adherent CPAP use. Pathway analysis and miRNA target gene enrichment were performed in silico. Plasma levels of peptides and hormones related to cardiovascular function were also measured.


RESULTS
The OSA responder group exhibited blood pressure decreases exceeding the observed median (>4.5 mm Hg) after CPAP, which were not present in the nonresponder group (≤4.5 mm Hg) (p < 0.01). Three miRNAs provided a discriminatory predictive model for such a favorable blood pressure response to CPAP (area under the curve: 0.92; p = 0.01). Additionally, CPAP treatment significantly altered a total of 47 plasma miRNAs and decreased aldosterone-to-renin ratios in the responder group (p = 0.016) but not in the nonresponder group.


CONCLUSIONS
A singular pre-CPAP treatment cluster of 3 plasma miRNAs predicts blood pressure responses to CPAP treatment in patients with RH and OSA. CPAP treatment is accompanied by changes in cardiovascular system-related miRNAs that may potentially influence the risk for cardiovascular disease among patients with OSA and RH. (Effect of Continuous Positive Airway Pressure [CPAP] Treatment in the Control of Refractory Hypertension; NCT00616265).
Pulse discrete cosine transform for saliency-based visual attention

This paper proposes a saliency-based attention model based on pulsed cosine transform that simulates the lateral surround inhibition of neurons with similar visual features. The model can be extended to Hebbian-based neural networks. The visual saliency can be represented in binary codes, which agrees with the firing pulse of neurons in human brain. In addition, motion saliency can be directly generated by these pulse codes. Due to its good performance in eye fixation prediction and low computational complexity, our model can be used in real-time system such as robot navigation, virtual human system, and intelligent auto-focus system embedded in digital camera.
A Network Flow Approach to Throughput Maximization in Cooperative OFDMA Networks

In wireless cooperative orthogonal frequency-division multiple-access (OFDMA) networks, it is important to adapt the transmission strategies for each user according to the network channel dynamics in order to optimize the overall system performance. The adaption involves transmission mode selection (a user can choose from direct or cooperative transmission), subcarrier assignment, subcarrier pairing (the incoming and outgoing subcarriers at the relay for cooperative transmission need to be matched), relay selection, as well as power allocation and hence is highly challenging. Many previous works only consider a subset of the adaptation. In this paper, we tackle the joint optimization problem using a network flow approach. Specifically, we first show that for given power allocation, the combinatorial optimization problem of transmission mode selection, subcarrier assignment, relay selection and subcarrier pairing for the system total throughput maximization can be transformed into a minimum cost network flow (MCNF) problem with integer solutions. The linear optimal distribution (LOD) algorithm is applied to find the optimal solution in polynomial time. We then solve the mixed integer programming problem of the joint assignment and power allocation in an asymptotically optimal way in the dual domain. Simulation results show that the proposed algorithms can significantly enhance the overall system throughput.
A positive association between anxiety disorders and cannabis use or cannabis use disorders in the general population- a meta-analysis of 31 studies

BACKGROUND
The aim of the current study was to investigate the association between anxiety and cannabis use/cannabis use disorders in the general population.


METHODS
A total of N = 267 studies were identified from a systematic literature search (any time- March 2013) of Medline and PsycInfo databases, and a hand search. The results of 31 studies (with prospective cohort or cross-sectional designs using non-institutionalised cases) were analysed using a random-effects meta-analysis with the inverse variance weights. Lifetime or past 12-month cannabis use, anxiety symptoms, and cannabis use disorders (CUD; dependence and/or abuse/harmful use) were classified according to DSM/ICD criteria or scores on standardised scales.


RESULTS
There was a small positive association between anxiety and either cannabis use (OR = 1.24, 95% CI: 1.06-1.45, p = .006; N = 15 studies) or CUD (OR = 1.68, 95% CI: 1.23-2.31, p = .001; N = 13 studies), and between comorbid anxiety + depression and cannabis use (OR = 1.68, 95% CI: 1.17-2.40, p = .004; N = 5 studies). The positive associations between anxiety and cannabis use (or CUD) were present in subgroups of studies with ORs adjusted for possible confounders (substance use, psychiatric illness, demographics) and in studies with clinical diagnoses of anxiety. Cannabis use at baseline was significantly associated with anxiety at follow-up in N = 5 studies adjusted for confounders (OR = 1.28, 95% CI: 1.06-1.54, p = .01). The opposite relationship was investigated in only one study. There was little evidence for publication bias.


CONCLUSION
Anxiety is positively associated with cannabis use or CUD in cohorts drawn from some 112,000 non-institutionalised members of the general population of 10 countries.
Maximal voluntary isometric contraction exercises: a methodological investigation in moderate knee osteoarthritis.

PURPOSE
The objectives were, (i) to determine whether differences exist in relative activation amplitudes for participants with asymptomatic knees and participants with moderate medial compartment knee osteoarthritis during a series of maximal effort contractions and (ii) to determine whether maximum activations occurred on similar exercises for both groups.


SCOPE
Sixty-eight participants with asymptomatic knees and 68 participants with moderate medial compartment knee osteoarthritis completed eight standardized 3-s maximal voluntary isometric exercises. Maximal electromyographic amplitudes were identified for a 100 ms window from three quadriceps, two gastrocnemius and two hamstring muscle sites for each exercise. For each exercise, amplitudes were normalized to percent of the absolute maximum activation (%MVIC). Frequency counts for exercises eliciting absolute maximum amplitudes were recorded. Analysis of variance models determined exercise and group main effects and interactions in relative amplitudes (%MVIC) for each muscle.


CONCLUSION
The exercises produced similar relative activation amplitudes between groups. The highest relative amplitude occurred for gastrocnemius during standing plantarflexion (86-93%MVIC), for the vasti during knee extension (45°) and (15°) (81-86%MVIC), for rectus femoris during knee extension (15°) (89%MVIC) and for hamstring muscles during knee flexion (15°) and prone knee flexion (55°) (81-94%MVIC). No single exercise elicited absolute maximum activation for every participant for each muscle, supporting the value of using an exercise series for normalization purposes.
Quantitative and qualitative network robustness analysis under different multiple failure scenarios

Society depends now more strongly than ever on large-scale networks. Failures of great significance have occurred in the last years. Thus, it has become of vital importance to define robustness metrics. Classical robustness analysis has been focused on the evaluation of topological characteristics. In this paper we extend this analysis introducing two new robustness metrics that include traffic service requirements: QuaNtitative Robustness Metric (QNRM) and QuaLitative Robustness Metric (QLRM). A review of some well known graph robustness metrics is provided. In order to compare these metrics with the proposals, a set of six topologies (random, small-world and scale-free) is evaluated. Finally, it is shown that our two new metrics are able to evaluate the performance of a network under a given kind of impairment.
REALISTIC EVALUATION OF SEMI-SUPERVISED LEARNING ALGORITHMS

Semi-supervised learning (SSL) provides a powerful framework for leveraging unlabeled data when labels are limited or expensive to obtain. Approaches based on deep neural networks have recently proven successful on standard benchmark tasks. However, we argue that these benchmarks fail to address many issues that these algorithms would face in real-world applications. After creating a unified reimplementation of various widely-used SSL techniques, we test them in a suite of experiments designed to address these issues. We find that simple baselines which do not use unlabeled data can be competitive with the state-of-the-art, that SSL methods differ in sensitivity to the amount of labeled and unlabeled data, and that performance can degrade substantially when the unlabeled dataset contains out-of-class examples. This workshop paper is outdated. Please visit the updated, full version on arXiv: https: //arxiv.org/abs/1804.09170
Correlation of pulsatility index with intracranial pressure in traumatic brain injury.

AIM
In traumatic brain injury (TBI) patients, it is desired to monitor the intracranial pressure (ICP) to assess the cerebral haemodynamics and guide the therapy. The study was designed to see if the pulsatility index (PI) measured by transcranial Doppler ultrasonography (TCD) predicts information about ICP values.


MATERIAL AND METHODS
In 52 TBI patients with Glasgow Coma Scale (GCS) score < 9, invasive intracranial monitoring and TCD ultrasonography for PI were performed through five days. ICP, cerebral perfusion pressure (CPP), PI values were recorded and calculated. The correlation and regression analysis between ICP, PI and CPP were investigated in the whole group and in patients with a Glasgow Outcome Score (GOS) of 3-5.


RESULTS
The decline in ICP and PI values was significant through five days. The correlation between ICP and PI was strongly significant (p < 0.0001) on days 1, 3 and 5. In patients with a GOS of 3-5, correlation of ICP and PI was also observed. The only significant correlation observed between CPP and PI was on day 5.


CONCLUSION
The strong correlation observed between ICP and PI through the management period of TBI patients can lead us to use TCD ultrasonography-derived PI as a guide if invasive monitoring is not available.
A Review on High-Speed Machining of Titanium Alloys ∗

Titanium alloys have been widely used in the aerospace, biomedical and automotive industries because of their good strength-to-weight ratio and superior corrosion resistance. However, it is very difficult to machine them due to their poor machinability. When machining titanium alloys with conventional tools, the tool wear rate progresses rapidly, and it is generally difficult to achieve a cutting speed of over 60 m/min. Other types of tool materials, including ceramic, diamond, and cubic boron nitride (CBN), are highly reactive with titanium alloys at higher temperature. However, binder-less CBN (BCBN) tools, which do not have any binder, sintering agent or catalyst, have a remarkably longer tool life than conventional CBN inserts even at high cutting speeds. In order to get deeper understanding of high speed machining (HSM) of titanium alloys, the generation of mathematical models is essential. The models are also needed to predict the machining parameters for HSM. This paper aims to give an overview of recent developments in machining and HSM of titanium alloys, geometrical modeling of HSM, and cutting force models for HSM of titanium alloys.
Copy move forgery detection using DWT and SIFT features

Powerful image editing tools like Adobe Photoshop etc. are very common these days. However due to such tools tampering of images has become very easy. Such tampering with digital images is known as image forgery. The most common type of digital image forgery is known as copy-move forgery wherein a part of image is cut/copied and pasted in another area of the same image. The aim behind this type of forgery may be to hide some particularly important details in the image. A method has been proposed to detect copy-move forgery in images. We have developed an algorithm of image-tamper detection based on the Discrete Wavelet Transform i.e. DWT. DWT is used for dimension reduction, which in turn increases the accuracy of results. First DWT is applied on a given image to decompose it into four parts LL, LH, HL, and HH. Since LL part contains most of the information, SIFT is applied on LL part only to extract the key features and find descriptor vector of these key features and then find similarities between various descriptor vectors to conclude that the given image is forged. This method allows us to detect whether image forgery has occurred or not and also localizes the forgery i.e. it tells us visually where the copy-move forgery has occurred.
Comparative fracture risk in vegetarians and nonvegetarians in EPIC-Oxford

Objective:To compare fracture rates in four diet groups (meat eaters, fish eaters, vegetarians and vegans) in the Oxford cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Oxford).Design:Prospective cohort study of self-reported fracture risk at follow-up.Setting:The United Kingdom.Subjects:A total of 7947 men and 26 749 women aged 20–89 years, including 19 249 meat eaters, 4901 fish eaters, 9420 vegetarians and 1126 vegans, recruited by postal methods and through general practice surgeries.Methods:Cox regression.Results:Over an average of 5.2 years of follow-up, 343 men and 1555 women reported one or more fractures. Compared with meat eaters, fracture incidence rate ratios in men and women combined adjusted for sex, age and non-dietary factors were 1.01 (95% CI 0.88–1.17) for fish eaters, 1.00 (0.89–1.13) for vegetarians and 1.30 (1.02–1.66) for vegans. After further adjustment for dietary energy and calcium intake the incidence rate ratio among vegans compared with meat eaters was 1.15 (0.89–1.49). Among subjects consuming at least 525 mg/day calcium the corresponding incidence rate ratios were 1.05 (0.90–1.21) for fish eaters, 1.02 (0.90–1.15) for vegetarians and 1.00 (0.69–1.44) for vegans.Conclusions:In this population, fracture risk was similar for meat eaters, fish eaters and vegetarians. The higher fracture risk in the vegans appeared to be a consequence of their considerably lower mean calcium intake. An adequate calcium intake is essential for bone health, irrespective of dietary preferences.Sponsorship:The EPIC-Oxford study is supported by The Medical Research Council and Cancer Research UK.
Semantics Based on Conceptual Spaces

The overall goal is to show that conceptual spaces are more promising than other ways of modelling the semantics of natural language. In particular, I will show how they can be used to model actions and events. I will also outline how conceptual spaces provide a cognitive grounding for word classes, including nouns, adjectives, prepositions and verbs.
Effectiveness of varenicline and counselling for smoking cessation in an observational cohort study in China

OBJECTIVES
To evaluate the effectiveness of varenicline for smoking cessation in Chinese smokers in a real world cessation clinic practice.


DESIGN
A prospective observational study.


SETTING
Beijing, China.


PARTICIPANTS
A total of 924 smokers (883 men and 41 women) who attended a smoking cessation clinic of a large general hospital were assessed with data from structured questionnaires at baseline and follow-up at 1, 3 and 6 months. Trained physician counsellors provided free individual counselling for all subjects and follow-up interviews with brief counselling. 332 subjects additionally prescribed varenicline according to their own choice were compared with those without varenicline.


MAIN OUTCOME MEASURES
Primary outcomes were self-reported 7-day point prevalence abstinence rate and 3-month continuous abstinence rate at 6-month follow-up. Secondary outcomes were 7-day point prevalence abstinence rates at 1 and 3-month follow-up, and 1-month continuous abstinence rate at 3-month follow-up.


RESULTS
By intention-to-treat, the 7-day point prevalence abstinence rate with varenicline and counselling at 6 months was significantly higher than counselling only (37.0% vs 23.1%; OR, 1.75; 95% CI 1.46 to 2.62; p=0.001). The 3-month continuous abstinence rate at 6 months was higher with varenicline (33.1% vs 18.4%; OR, 2.04; 95% CI 1.61 to 2.99; p<0.001). Varenicline also showed better secondary outcomes.


CONCLUSIONS
Varenicline prescription in the smoking cessation clinic appeared to be effective with doubling of quit rates in Chinese smokers in a real world cessation clinic practice.


CLINICAL TRIAL REGISTRATION
NCT01935505; Results.