Rapid Descent Research Articles

Zoledronic acid sequential therapy could avoid disadvantages due to the discontinuation of less than 3-year denosumab treatment.

IntroductionRapid descent in bone mineral density (BMD) and ascent in bone turnover marker (BTM) occur within the short period following denosumab (Dmab) discontinuation. In addition, the incidence of vertebral fracture also rises within the short period. The purpose of this study is to investigate the effects of sequential therapy using zoledronic acid (ZOL) on any adverse events after Dmab discontinuation.Materials and methodsThis study was a multicenter retrospective observational study, and the subjects were osteoporosis patients who visited our institutions between 2013 and 2018. We performed sequential therapy using ZOL for 30 patients who had difficulty continuing Dmab, due to physical or social reasons, and investigated the fracture incidence and BMD/BTM changes at 4 time points (at the start of Dmab, the start of ZOL, 6 months after ZOL and 12 months after ZOL).ResultsNo new vertebral/nonvertebral fractures were observed at each time point after switching from Dmab to ZOL in any of the 30 patients. The BMD/BTM changes were evaluated in 18 of the 30 cases, since all data of lumbar/femoral neck BMDs and TRACP-5b at 4 time points was only available in 18 cases. BMDs significantly increased at each time point compared with that at the start of Dmab. Serum TRACP-5b significantly decreased at each time point compared with that at the start of Dmab.ConclusionIt was suggested that sequential therapy using ZOL could suppress the decrease of BMD, and increase of BTM, if the period of Dmab administration was less than 3 years.Electronic supplementary materialThe online version of this article (10.1007/s00774-020-01126-w) contains supplementary material, which is available to authorized users.

Topology optimization of photonics devices: fluctuation-trend analysis concept; random initial conditions with Gaussian and Durden–Vesecky power density bandlimited spectra

We present a topology optimization method for a 1D dielectric metasurface, based on a new concept: fluctuation and trend analysis for initial random conditions. The key point of the proposed optimization method is that the procedure initially generates a couple of device distributions termed fluctuation/mother and trend/father, with specific spectra that efficiently sample not the local minimum of the objective function but basins of optimal solutions in the design space. Studying a 1D dielectric metagrating deflecting a normal polarized incident wave onto a range of angles, we show that a suitable choice of a specific power density spectrum for this initial couple highly increases the probability of reaching a basin of high-performance devices. We guess initial geometries holding the physical properties of the desired final device, allowing accurate targeting of these high-performance device basins in the design space. To include desired physical properties in the initial geometry model, we introduce a formalism allowing generation of a random process with a particular power density or correlation function. By means of a suitable definition of the trend function, we identify an ultimate power density bandlimited spectrum for the fluctuation functions allowing a very high probability and leading to a rapid descent to favorable basins of optimal solutions, consequently reaching high-performance final structure in the design space.

Rabbit Hole: Photography, Magic and Reality

The Rabbit Hole projects simultaneously question the present-day reality and unveil the ways of its technological embeddedness while hinting on the possibilities of its future permutations. Are we really in contact with reality? Or are we left at the mercy of constant flickering and perpetually changing simulations, copies, and representations? Which one is the right one? But, truly, is this even the right question? The exhibition projects revolve around of the failed encounter of the reality and photography – on their descent into phantasmagorical landscapes of contemporary visibility and on the social consequences of the intoxication that this rapid descent brings. As a contemporary versions of the burnt images from the Cuna indigenous rituals they create an illusion and defend us against the “cold” petrifying, spectral order of technology – but then again – just maybe they only anesthetize us just before we crash into dystopian social reality.

Bookends to a Gentler Capitalism: Complicating the Notion of First and Second Gilded Ages

AbstractThe narrative of a second Gilded Age erroneously suggests that the current dynamics are repeating those of the late nineteenth century. Although they share certain important characteristics, these are profoundly different historical moments. Focusing on the history of capitalism and labor, and taking a global perspective, demonstrates that the two periods were bookends—the “before” and “after” to a lengthy period when the cruelest characteristics of corporate capitalism were temporarily constrained. The late nineteenth century saw the ascent of serious efforts to rein in the power of the new capitalism and force it to bow down to the needs of civil society. During the late twentieth and early twenty-first centuries, we are experiencing the decline of that effort as capitalists and their ideological and political supporters push to see how far they can go to ensure the unchallenged hegemony of corporate and property rights. The slow climb toward a more humane capitalism and the rapid descent away from it constitute two very different experiences.

Forecasting Stock Prices Using a Hybrid Deep Learning Model Integrating Attention Mechanism, Multi-Layer Perceptron, and Bidirectional Long-Short Term Memory Neural Network

Stock prices forecasting is a topic research in the fields of investment and national policy, which has been a challenging problem owing to the multi-noise, nonlinearity, high-frequency, and chaos of stocks. These characteristics of stocks impede most forecasting models from extracting valuable information from stocks data. Herein, a novel hybrid deep learning model integrating attention mechanism, multi-layer perceptron, and bidirectional long-short term memory neural network is proposed. First, the raw data including four types of datasets (historical prices of stocks, technical indicators of stocks closing prices, natural resources prices, and historical data of the Google index) are transformed into a knowledge base with reduced dimensions using principal component analysis. Subsequently, multi-layer perceptron is used for the fast transformation of feature space and rapid gradient descent, bidirectional long-short term memory neural network for extracting temporal features of stock time series data, and attention mechanism for making the neural network focus more on crucial temporal information by assigning higher weights. Finally, a comprehensive model evaluation method is used to compare the proposed model with seven related baseline models. After extensive experiments, the proposed model demonstrated its good forecasting performance.

CITADELS AND SURVEILLANCE: CONFLICTIVE REGIONS AND DEFENSIVE DESIGN IN THE BUENAVISTA CITADELS OF GUATEMALA

Maya conflict left many images. With a few exceptions, however, they reveal limited numbers of victors and captives In contrast, glyphic accounts point to broader convulsions, and the challenge remains of linking such conflicts to the infrastructure of concerted attack and defense. Lidar, a technology using laser pulses to record and model surfaces, does so with aplomb. By now, most Mayanists accept that, in the late 4th century A.D., Classic Maya kingdoms became entangled with the distant polity of Teotihuacan, Mexico. Tikal refers to that encounter in precise detail, identifying an enigmatic, victorious belligerent, Sihyaj K’ahk’, and possible ruptures in the local dynasty. To unexpected extent, lidar shows that the western entry to Tikal bristled with numerous citadels, surveillance platforms, moats with protected settlement, and ramps for rapid ascent and descent on high ridges and hilltops. Current evidence places these features in the general time of Sihyaj K’ahk’, underscoring that the threat and actuality of violence enmeshed regions, at systemic scale.

Effect of external resistance on substrate removal and electricity generation in microbial fuel cell treating sulfide and nitrate simultaneously.

The effect of external resistance on substrate removal and electricity generation was explored in microbial fuel cells (MFCs) simultaneously treating sulfide and nitrate. The MFCs were operated under three different conditions keeping open-circuit MFC as control. In batch mode, all the MFCs showed good capacity of simultaneously removing sulfide and nitrate regardless of external resistance. The voltage profile could be divided into rapid descent zone, bulge zone, and stability zone, which represents typical polarization behavior. Taking open circuit as control, low external resistance promoted the production of sulfate and nitrogen gas, while a strong link between product production and external resistance was evident based on Pearson correlation analyses. In addition, low external resistance improved the amount of transferred electrons, while the peak electronic quantity was noticed when the external resistance was equivalent to internal resistance. Moreover, the mechanism of substrate removal and electricity generation was hypothesized for the MFCs simultaneously treating sulfide and nitrate which explained the results well.

4087Functional assessment of the myocardium in non-ischaemic cardiomyopathy using manganese-enhanced T1 mapping

Abstract Background Delayed-enhancement magnetic resonance imaging (DEMRI) with gadolinium detects macroscopic myocardial fibrosis, but does not directly assess myocardial function. Manganese, a paramagnetic calcium-analogue, enables direct dynamic assessment myocyte calcium handling and is a potential early marker of myocardial dysfunction. We have previously demonstrated manganese-enhanced MRI (MEMRI) can detect altered calcium-handling in remote remodelling myocardium in a rodent infarct model. Purpose To evaluate MEMRI as a marker of altered myocardial calcium handling in patients with non-ischaemic cardiomyopathy (NCT03607669). Methods Healthy volunteers (HV, n=20, 13 male, 42±11 years) and patients with hypertrophic (HCM, n=11, 5 male, 57±15 years) or dilated (DCM, n=5, 3 male, 56±14 years) cardiomyopathies underwent both DEMRI and MEMRI. Myocardial T1 was measured for 40 min after intravenous manganese dipyridoxyl diphosphate (Mn-DPDP, 5 μmol/kg) administration. Images were acquired at 3T with T1 imaging performed using Shortened Modified Look-Locker Inversion recovery [Figure A] (WIP #1048 Siemens Healthcare Ltd). Results No adverse effects were observed. In HV, the myocardialT1 profile following Mn-DPDP administration demonstrated a rapid initial descent (perfusion phase) followed by a slower, more gradual decrease which continued throughout the 40 min imaging period (mean reduction 25.2%, 283±9ms). In patients with HCM, T1 values followed a different pattern following Mn-DPDP administration. In areas of focal myocardial fibrosis (defined by DEMRI) there was again a sharp initial shortening of T1 but this was followed by a steady increase towards baseline, which eventually recovered to >40% of its initial value at 40 minutes. In areas of diffuse myocardial fibrosis, the initial shortening in the perfusion phase was followed by a more gradual recovery which then plateaued, remaining stable at 21% of native T1 by 40 min [Figure B]. Hypertrophied non-fibrosed myocardium had higher native T1 than HV (1178±45 vs 1133±36 ms P=0.005) and the rate of T1 reduction following the perfusion phase was slower (P=0.0005), leading to less overall T1 shortening at 40 min (880±40 vs 841±28 ms, P=0.004, [Figure C]). No patient with DCM had fibrosis by DEMRI. Native T1 was higher than HV (1234±26 vs 1133±36 ms, P<0.0001) and the rate of T1 reduction following the perfusion phase was lower in DCM myocardium (P<0.0001) resulting in less overall T1 shortening at 40 min (914±60 vs 841±28 ms, P=0.0006, [Figure D]). MEMRI in non-ischaemic cardiomyopathy Conclusion MEMRI identifies altered calcium-handling in pathological myocardium of non-ischaemic cardiomyopathy, irrespective of fibrosis by DEMRI. This feasible, safe and novel method of functional myocardial tissue characterisation has exciting potential for future diagnostic, functional and clinical applications. Acknowledgement/Funding British Heart Foundation

Protozoan predation of Escherichia coli in hydroponic media of leafy vegetables

ABSTRACT Multiple outbreaks of food poisoning associated with fresh vegetable consumptions have occurred in many countries. Numerous reports have described human pathogenic bacteria, such as Escherichia coli O157:H7 and Salmonella spp., that can internalize into fresh vegetables via root or leaf surfaces. While attempting to obtain the threshold concentration of internalization of E. coli inoculated into hydroponic medium during vegetable cultivation, we observed a rapid decrease in E. coli numbers. In the present study, we determined that the rapid decline in E. coli was not due to a physiological change into a viable but non-culturable (VNC) state. The population crash was instead caused by true bacterial death, as the rapid descent was also confirmed by micro-colony fluorescence in situ hybridization, a culture-independent method that can detect VNC cells. We next monitored the number of E. coli inoculated into intact or filter-sterilized hydroponic medium after cultivation of various types of plants. We found that the number of E. coli in intact hydroponic medium decreased markedly, whereas the level in filter-sterilized hydroponic medium was completely unchanged. This result suggests that biotic factors were present that could be eliminated by filtering. Robust predation of E. coli by protozoa (ciliates and flagellates) was observed using fluorescently labeled bacteria incorporated into the hydroponic medium. Finally, morphological identification of flagellates by scanning electron microscopy revealed the presence of a species of Stramenopiles. These findings suggest the importance of protozoa as bacterial feeders in hydroponic systems and hence the use of these organisms as potential control agents of human pathogenic bacteria.

Study on corrosion effect of high-performance concrete under the action of sulfate and chlorine

The thickness of corroded concrete layer and the compressive strength of prisms under the action of sulfate and chloride salt were investigated by ultrasonic test and compression test, respectively. The results show that under the single action of sulfate, the strength of concrete experienced two stages: a slow growth stage and a rapid descent stage. Correspondingly, under the combined action of sulfate and chloride, the concrete strength experienced another two stages: a slow growth stage and a slow degradation stage. The existence of chloride inhibited the corrosion damage of concrete in a certain extent. It was found that higher concentration of chlorine salt would lead to a stronger inhibition effect. A good consistency was observed among corrosion layer thickness, compressive strength and X-ray diffraction results. The inhabitation of chloride to the sulfate corrosion of concrete was proved.

Brainstem spreading depolarization: rapid descent into the shadow of SUDEP.

This scientific commentary refers to ‘Brainstem spreading depolarization and cortical dynamics during fatal seizures in Cacna1a S218L mice’ by Loonen et al. (doi: 10.1093/brain/awy325 ).

Headache Attributed to Aeroplane Travel: An Historical Outline.

Headache attributed to aeroplane travel (AH) is one of the new nosological entries in the International Classification of Headache Disorders (ICHD) 3 beta. This study retraces the history of headache related to flight, from the initial description to the modern reports, on the basis of original sources. Head pain related to flight has been reported since the beginning of flight era. However, most of those early cases are easily recognized as secondary to an exceptional barotrauma and/or a sinusitis concomitant with the flight. Instead, contemporary research identified a new nosological entity, AH, which by definition occurs in normal flying conditions and in absence of any sinus pathology. Moreover, we identified recently similar forms of headache, triggered by sudden changes of external pressure (rapid descent from mountain, mountain descent headache, MDH); and ascent from diving, diving ascent headache (DAH). Head pain related to flight has been reported since the origin of aviation, but it was caused by an exceptional barotrauma or a respiratory infection. Instead, AH occurs in normal flying conditions. Two newly identified conditions, MDH and DAH, appear to share a common pathogenetic mechanism with AH: namely the imbalance between intrasinusal and external air pressure. Therefore, we assert that an expansion of this entity of AH is something that should be considered in the next ICHD.

Rapid descent flight by a molossid bat (Chaerephon plicatus) returning to its cave

In Southeast Asia, wrinkle-lipped bats (Chaerephon plicatus) roost in colonies that may count several million individuals. Birds of prey frequently hunt these bats when they emerge from or return to their colonies. Here, we report on an extreme anti-predator behavior of this species during return flights at dawn. Based on data logger, we documented that bats may ascend to several hundred meters altitude above the cave shortly before diving at high speed (maximum 20 m/s) towards the entrance. Dive rates were 40 times higher than those reported for other open-space foraging bats performing flapping descending flights. Based on high speed video recordings, we show that C. plicatus brake the rapid descents close to the cave entrance using the tail wing membrane and partly extended wings. Maximum gravitational forces involved 2.4 G, probably when adjusting abruptly the speed close to ground. We argue that these descending maneuvers may constitute an anti-predator strategy of C. plicatus, since such descents may be too fast and complex for birds of prey at the cave entrance, particularly when performed by thousands of individuals at the same time.

Northern Hemisphere Stratospheric Ozone Depletion Caused by Solar Proton Events: The Role of the Polar Vortex

AbstractOzonesonde data from four sites are analyzed in relation to 191 solar proton events from 1989 to 2016. Analysis shows ozone depletion (~10–35 km altitude) commencing following the SPEs. Seasonally corrected ozone data demonstrate that depletions occur only in winter/early spring above sites where the northern hemisphere polar vortex (PV) can be present. A rapid reduction in stratospheric ozone is observed with the maximum decrease occurring ~10–20 days after solar proton events. Ozone levels remain depleted in excess of 30 days. No depletion is observed above sites completely outside the PV. No depletion is observed in relation to 191 random epochs at any site at any time of year. Results point to the role of indirect ozone destruction, most likely via the rapid descent of long‐lived NOx species in the PV during the polar winter.

Reaction Forces on a Fixed Ladder in Static Equilibrium: Analysis and Definitive Experimental Test of the Ladder Problem

The development of a theoretical model to predict the four equilibrium forces of reaction on a simple ladder of non-adjustable length leaning against a wall has long remained an unresolved matter. The difficulty is that the problem is statically indeterminate and therefore requires complementary information to obtain a unique solution. This paper reports 1) a comprehensive theoretical analysis of the three fundamental models based on treating the ladder as a single Euler-Bernoulli beam, and 2) a detailed experimental investigation of the forces of reaction as a function of applied load and location of load. In contrast to previous untested proposals that the solution to the ladder problem lay in the axial constraint on compression or the transverse constraint on flexure, the experimental outcome of the present work showed unambiguously that 1) the ladder could be modeled the best by a pinned support at the base (on the ground) and a roller support at the top (at the wall), and 2) the only complementary relation needed to resolve the static indeterminacy is the force of friction at the wall. Measurements were also made on the impact loading of a ladder by rapid ascent and descent of a climber. The results obtained were consistent with a simple dynamical model of the ladder as a linear elastic medium subject to a pulse perturbation. The solution to the ladder problem herein presented provides a basis for theoretical extension to other types of ladders. Of particular importance, given that accidents involving ladders in the workplace comprise a significant fraction of all industrial accidents, the theoretical relations reported here can help determine whether a collapsed structure, against which a ladder was applied, met regulatory safety limits or not.

Changes in corneal thickness in patients with high-altitude pulmonary edema after systemic oxygen therapy.

Purpose:High-altitude pulmonary edema (HAPO) is an acute medical emergency occurring typically in lowlanders, who ascend rapidly to heights of 3000 m or more. It presents with marked dyspnea on exertion, fatigue with minimal-to-moderate effort, prolonged recovery time, and dry cough with manifestations of cyanosis, tachycardia, tachypnea, and temperature which generally does not increase beyond 38.5°C. The condition may be fatal if not treated in time with supplemental oxygen or hyperbaric oxygen or rapid descent to lower altitude. There is paucity in literature on changes in corneal thickness in HAPO. The effect of continued oxygen therapy on corneal thickness has also not been studied in detail. Hence, this study was conducted at high altitude among physician-confirmed HAPO cases.Methods:A case–control study was conducted at an altitude of 11,400 feet. Cases were patients suffering from HAPO and controls were patients admitted in hospital for low back pain, fractures, and minor surgical procedures. Central corneal thickness (CCT) was measured with an ultrasound pachymeter on day 1 of hospitalization and every day of hospital stay. Systemic oxygen concentration was also measured daily.Results:There was no statistically significant difference in corneal thickness between two groups at the onset of illness, but a significant decrease in CCT was found in both right and left eyes in HAPO cases when oxygen levels were increased by giving supplemental oxygen. Hierarchical modeling showed a decrease in 1.3 μm in CCT with one unit increase in oxygen mmHg in cases.Conclusion:The findings of statistically insignificant difference in CCT between HAPO cases and controls and a decrease in CCT in HAPO cases on being treated with systemic oxygenation are points to ponder about.

Aeroplane headache, mountain descent headache, diving ascent headache.. Three subtypes of headache attributed to imbalance between intrasinusal and external air pressure?

Background Headache attributed to aeroplane travel (AH) is currently codified in Chapter 10.1.2 of the International Classification of Headache Disorders 3 beta (ICHD 3 beta). After our previous papers, the investigation was enlarged to 200 patients. Material and methods People affected by AH contacted us by mail and agreed to fill in a detailed anonymous questionnaire that allowed a thorough definition of the headache features. Results This extended case series allows us to confirm most of the clinical features of AH, reported in our previously published article, and to partially modify others. New results mainly regard the higher occurrence of accompanying symptoms and the presence of a long lasting mild headache phase, usually not exceeding 24 h, that follows the short lasting acute pain, the duration of which has been confirmed as less than 30 min. Moreover, headache attacks identical to those of AH are reported in a portion of patients, triggered by the ascent during free/snorkeling or scuba diving and rapid descent from high mountains. Conclusion The coexistence of AH with headache triggered by different environmental factors (ascent during free/scuba diving and descent from high mountains) indicates a common causal mechanism, that is, the imbalance between intrasinusal and external air pressure. We propose to classify them together, within Chapter 10 " Headache attributed to disorders of homoeostasis", under a unique heading " Headache attributed to imbalance between intrasinusal and external air pressure".

ВПЛИВ ФУНКЦІОНУВАННЯ ЯВІРСЬКОЇ ГЕС НА УГРУПОВАННЯ БЕЗХРЕБЕТНИХ ГІДРОБІОНТІВ Р. СТРИЙ (УКРАЇНСЬКІ КАРПАТИ)

The most negative impact of Yavirska HPP on the aquatic invertebrate communities of river Stryi is noted along four kilometers stretch below the dam. Taxonomic diversity, abundance and biomass of the communities on this part of the river decreases in two to three times compare to the sampling sites above Yavirske reservoir. At a distance over six kilometers below the dam structural parameters of the invertebrate groups are restored to the natural status (like the sampling sites above the reservoir). The number of individuals of the drift after passing through the reservoir and the dam decreases tenfold on average. Water of the investigated river stretch is slightly polluted (the sites, which are outside from the direct influence of the HPP functioning) and moderately polluted (the reservoir by it self and the sites located in the zone of HPP influence). The results of our investigations point out the main negative factors, that are as follows: limnethic conditions of the reservoir in the river continuum, accumulation of silt and clay sediments on the bottom and the banks of the reservoir, demolition of sediments in the lower stretch of the river, destruction of the river bottom substrate below the dam due to the rapid descent of large masses of water, instant shallowing of the Striy river bed below the dam after the closing of station sluice in June, and some hydro-ground works below the dam.

Acute high-altitude illness

A substantial proportion of South Africa (SA)’s population lives at high altitude (>1 500 m), and many travel to very high altitudes (>3 500 m) for tourism, business, recreation or religious pilgrimages every year. Despite this, knowledge of acute altitude illnesses is poor among SA doctors. At altitude, the decreasing ambient pressure proportionally decreases available oxygen (hypobaric hypoxia). This triggers both immediate respiratory compensation and gradual acclimatisation that occurs over days to weeks. Rapid ascents to altitudes above 2 500 m can precipitate acute altitude illness, including acute mountain sickness (AMS) and high-altitude pulmonary and cerebral oedema (HAPE and HACE). The best preventive measure is gradual ascent (no more than 300 - 500 m increase in sleeping altitude per day, with additional rest days for acclimatisation for every 1 000 m altitude gain), although chemoprophylaxis may speed acclimatisation. In the field, AMS, HAPE and HACE are diagnosed clinically. The Lake Louise Score questionnaire is used to elicit symptoms of AMS, and can be supplemented by assessing clinical signs such as tachycardia, tachypnoea, crepitations or ronchi, and ataxia. The mainstay of treatment for all but mild AMS is rapid descent to lower altitudes, which can be facilitated by administration of oxygen and drugs, including acetazolamide, dexamethasone and nifedipine, or use of a portable hyperbaric chamber.

Global health at the Human-Animal-Ecosystem Interface - An online course.

The goal of the study was to characterize high altitude illness in Nepali pilgrims.We kept standardized records at the Himalayan Rescue Association (HRA) Temporary Health Camp at Gosainkund Lake (4380 m) in the Nepal Himalaya during the annual Janai Purnima Festival in 2014. Records included rate of ascent and Lake Louise Score (LLS). We defined High Altitude Headache (HAH) as headache alone or LLS = 2. Acute Mountain Sickness (AMS) was LLS≥3. High Altitude Cerebral Edema (HACE) was AMS with ataxia or altered mental status.An estimated 10,000 pilgrims ascended rapidly, most in 1–2 days, from Dhunche (1960 m) to Gosainkund Lake (4380 m). We saw 769 patients, of whom 86 had HAH. There were 226 patients with AMS, including 11 patients with HACE. We treated patients with HACE using dexamethasone and supplemental oxygen prior to rapid descent. Each patient with HACE descended carried by a porter. There were no fatalities due to HACE. There were no cases of High Altitude Pulmonary Edema (HAPE).HAH and AMS were common in pilgrims ascending rapidly to 4380 m. There were 11 cases of HACE, treated with dexamethasone, supplemental oxygen and descent. There were no fatalities.