bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cardiac Pacemaker Oscillation and Its Modulation by Autonomic Transmitters
Authors: Brown Hilary , Difrancesco Dario , Noble Susan 
Published: April 2021

ABSTRACT
A scheme is presented which summarizes the activation and deactivation of the membrane currents which underlie pacemaking in the natural pacemaker of the heart. Experimental evidence (mostly obtained using the voltage-clamp technique) for the properties of the time-dependent membrane currents in pacemaking tissue of the frog and the rabbit is discussed. The mode of the inhibitory action of acetylcholine on pacemaker cells is considered. In the amphibian pacemaker cell, acetylcholine probably reduces slow inward current (as it certainly does in amphibian atrium) but in mammalian sino-atrial node it seems that such action, if present at all, is much less marked. In the pacemakers of both amphibian and mammal, acetylcholine greatly increases outward potassium current and there is recent evidence that it may do so by opening up a special acetylcholine-activated potassium channel. Adrenaline greatly increases the slow inward current in pacemaker as in other cardiac tissues. This increase, together with (in mammal at least) an increased change of an additional pacemaking current, overrides an adrenaline-induced increase in outward current and leads to acceleration of the pacemaking rate. The Appendix contains a brief consideration of the experimental and theoretical basis for the method of exponential separation of outward current components in the presence of the extracellular potassium accumulation that inevitably accompanies the flow of outward membrane current.
Cellular and Subcellular Mechanisms of Cardiac Pacemaker Oscillations
Authors: Tsien R. W. , Kassr R. S. , Weingart R. 
Published: April 2021

ABSTRACT
Rhythmic oscillations in the membrane potential of heart cells are important in normal cardiac pacemaker activity as well as cardiac arrhythmias. Two fundamentally different mechanisms of oscillatory activity can be distinguished at the cellular and subcellular level. The first mechanism, referred to as a surface membrane oscillator, can be represented by a control loop in which membrane potential changes evoke delayed conductance changes and vice versa. Since the surface membrane potential is a key variable within the control loop, the oscillation can be interrupted at any time by holding the membrane potential constant with a voltage clamp. This mode of oscillation seems to describe spontaneous pacemaker activity in the primary cardiac pacemaker (sinoatrial node) as well as other regions (Purkinje fibre, atrial or ventricular muscle). In all tissues studied so far, the pacemaker depolarization is dominated by the slow shutting-off of an outward current, largely carried by potassium ions.
The second mechanism can be called an internal oscillator since it depends upon a subcellular rhythm generator which is largely independent from the surface membrane. Under voltage clamp, the existence of the internal oscillation is revealed by the presence of oscillations in membrane conductance or contractile force which occur even though the membrane potential is held fixed. The two oscillatory mechanisms are not mutually exclusive; the subcellular mechanism can be preferentially enhanced in any given cardiac cell by conditions which elevate intracellular calcium. Such conditions include digitalis intoxication, high Ca0, low Na0, low or high Ko, cooling, or rapid stimulation. Several lines of evidence suggest that the subcellular mechanism involves oscillatory variations in myoplasmic calcium, probably due to cycles of Ca uptake and release by the sarcoplasmic reticulum. The detailed nature of the Ca1 oscillator and its interaction with the surface membrane await further investigation.
Membrane Potential Oscillations In Molluscan “Burster” Neurones
Authors: Meech R. W. 
Published: April 2021

ABSTRACT
Membrane potential oscillations can be induced in molluscan neurones under a variety of artificial conditions. In the so-called ‘burster’ neurones oscillations are generated even in isolated cells. A likely mechanism for ‘bursting’ involves the following ionic currents:
A transient inward current carried by Na+ and Ca2+. This current is responsible for the upstroke of the action potentials. A delayed outward current carried by K+. This current is voltage-sensitive and is responsible for the downstroke of the action potential during the early part of the burst. It becomes progressively inactivated during the burst. Its amplitude depends on the intracellular pH. A rapidly developing outward current carried by K+ which is in-activated at potentials close to action potential threshold. This current tends to hold the membrane in the hyperpolarized state and is involved in spacing the action potentials. A prolonged inward current which may not inactivate. It is probably carried by both Na+ and Ca2+. This current is responsible for the depolarizing phase of the burst but also contributes to the action potential. A slowly developing outward current, carried by K+. This current appears as a result of a slow increase in intracellular ionized calcium and is responsible for the hyperpolarizing phase of the burst. Note that a transient increase in this current may also contribute to the falling phase of the action potential during the later stages of the burst. It is also sensitive to intracellular pH.
One of the more significant features of this system of producing membrane potential oscillations is that the frequency of the bursts depends on the rate at which the intracellular ionized calcium returns to its resting level. This process depends on the metabolic state of the animal which can thereby exert a considerable influence on the electrical activity of burster neurones.
DYNAMICS OF FERTILITY OF AGRICULTURAL CHERNOZEMS OF FOREST-STEPPE ZONE OF THE CENTRAL CHERNOZEM REGIONS OF RUSSIA
Authors: Surinov Artem 
Published: April 2021

The research was carried out to study the dynamics of fertility of arable soils in the southwestern part of the forest-steppe zone of the Central Chernozem region. The work was carried out according to the results of an agrochemical soil survey on the territory of Yakovlevsky district of Belgorod region. The soil cover was represented mainly by typical chernozems (57.7%) and leached (28.2%). Under these conditions, an increase in the average dose of organic fertilizers in the region from 6.5 t/ha in 2010–2014 up to 14.6 t/ha in 2015-2018 while maintaining the use of mineral fertilizers at the level of 82.9 kg a.i./ha, it became one of the main factors in the growth of the weighted average content of mobile forms of phosphorus in the soil from 101 to 167 mg/kg, potassium - from 120 to 183, sulfur - from 2.5 to 4.7, manganese - from 11.0 to 13.1, zinc - from 0.4 to 0.7 mg/kg. Bringing liming volumes in the region for 2015–2018 to 32.7 thousand hectares contributed to a decrease in the share of acidic soils from 84.7 in 2009 to 52.9% in 2018.Along with the improvement of the agrochemical parameters of arable soils, there was a significant increase in the yield of the main agricultural crops: winter wheat - from 3.38 to 4.55 t/ha, corn for grain - from 4.84 to 7.60 t/ha, sugar beet - from 36.8 to
56.4 t/ha
WALKING MOTION OPTIMIZATION OF THE WALKING MACHINE WITH DYNAMIC STABILITY
Authors: Aleynikov Yuriy Georgievich Yuriy 
Published: April 2021

The movement of machines with a walking legs is accompanied by dynamic vibrations of its body and a large energy consumption for the reciprocating movements of the legs. The greatest influence on the smoothness of the course is exerted by the alternating accelerations of the moving masses and the rigid contact of the leg with the ground surface. To reduce the negative factors affecting the smoothness of movement and energy consumption, are proposed to optimize the trajectory of movement of the legs. The optimized trajectory of the legs movement made it possible to reduce the consumption of electrical energy by 12 ... 18% per cycle of movement compared to the trajectory lying in the same geometric plane. In order to reduce shock loads, the time interval between the triggering of the shock sensor and the load sensor when lowering the support to the surface was experimentally determined, which was about 100 ms at a lowering speed of 20 mm/s. Reducing the speed of the leg at the moment of triggering the shock sensor after contact with the surface and its subsequent smooth loading made it possible to reduce shock loads and reduce body vibrations caused by sharp impacts of the feet on the surface. Support acceleration on impact decreased from 6g to 1.5g. The triggering of the shock sensor located on the support foot when it touches hard and soft surfaces requires adjusting the sensor's sensitivity while the machine is moving. Optimization of the algorithm for filtering false alarms and dynamic change in sensitivity did not give a satisfactory result, therefore, it is necessary to equip the design with additional load sensors that react to contact with the surface when lowering the support
FENOMENA CROSS HIJAB DAN PENGARUHNYA TERHADAP PERGESERAN SAKRALITAS KEAGAMAAN DI MASYARAKAT
Authors: Kamaludin Ihsan , Suheri Suheri 
Published: April 2021

Religion within Indonesian society is considered as a sacred institution. The appearance of a Cross Hijab phenomenon in social media has created a controversy for netizens because of its cross-gender clothing style. The presence of members of this group has caused unrest among most Muslims in Indonesia because its potential to decrease the sacredness of the hijab in society. This paper aims to analyze how cross hijab affects religious sacredness in society. This study used a qualitative approach in tracing cross-hijab group data on social media, and conducting a survey of 165 respondents from junior high school, high school, undergraduate, graduate, and non-Islamic boarding schools. The theory uses in this study is the sacred and profane theory of Mircea Eliade. The results showed that the emergence of the cross hijab phenomenon can have a major effect on the level of sacredness in some Islamic values of Indonesian Muslim communities. Besides, it also causes a shift in views and social situations regarding the function of hijab which theologically means sacred to something profane (accessories).Agama dalam masyarakat Indonesia merupakan salah satu institusi yang memiliki nilai sakral. Munculnya Cross Hijab di media sosial menimbulkan pro-kontra di masyarakat karena anggotanya mengenakan pakaian lintas gender yaitu hijab. Kehadiran anggota kelompok ini menimbulkan keresahan pada sebagian besar muslim di Indonesia karena dianggap dapat menggeser sakralitas hijab di masyarakat. Tulisan ini bertujuan untuk menganalisis bagaimana cross hijab mempengaruhi sakralitas keagamaan di masyarakat. Penelitian ini menggunakan pendekatan kualitatif berupa penelusuran data kelompok cross hijab di media sosial, dan diperkuat dengan melakukan survey terhadap 165 responden dari jenjang pendidikan SMP, SMA, S1, S2, S3, lulusan pesantren maupun non-pesantren. Adapun teori yang penulis gunakan sebagai alat analisis adalah teori sakral dan profan dari Mircea Eliade. Hasil penelitian menunjukan bahwa munculnya fenomena cross hijab dapat berpengaruh besar terhadap tingkat sakralitas pada sebagian nilai keislaman masyarakat muslim Indonesia. Disamping itu juga menimbulkan pergeseran pandangan dan situasi sosial tentang perubahan fungsi hijab yang secara teologis bermakna sakral menjadi sesuatu yang profan (aksesoris).
Heavy metal stress influence the andrographolide content, phytochemicals and antioxidant activity of Andrographis paniculata
Authors: Antony Anna , Nagella Praveen 
Published: April 2021

Heavy metals (HM) are toxic components present in the earth’s crust that can have a negative impact on plants as well as animals. Andrographis paniculata or ‘King of bitters’ belonging to the family Acanthaceae, is a medicinal herb traditionally used in the treatment of fever, common cold etc. In the present study, the effect of heavy metals (copper, tin and cobalt) on the andrographolide content, biochemical parameters like chlorophyll, carotenoid, protein, Total phenolic content (TPC), Total flavonoid content (TFC) and antioxidant activity in A. paniculata were analysed. Saplings of A. paniculata were treated at 50 and 100 mM concentrations, three different times at a time interval of 7 days. Andrographolide production was found to increase in copper and cobalt treated saplings when compared with the control. From the results, maximum andrographolide concentration was found in the saplings treated with 50 mM copper (8.51 mg/g of DW) and 50 mM tin (8.10 mg/g of DW) respectively. 50 mM cobalt treated plants have shown the highest concentration of TPC (17.21 mg/g of extract) and TFC (6.97 mg/g of extract). Notable variations in other biochemical parameters like total chlorophyll, carotenoid content and antioxidant activities were observed in all treatments compared with the control.
Impacts of Jobs Requiring Close Physical Proximity and High Interaction with the Public on U.S. Industry Employment Change During the Early Stages of the COVID-19 Pandemic
Authors: Gabe Todd , Florida Richard 
Published: April 2021

Abstract
This paper examines the factors affecting U.S. industry employment change in the early months of the COVID-19 pandemic. Results show that the percentage of industry employment in occupations that require close physical proximity has a negative effect on year-over-year employment change in the six months of April through September of 2020. On the other hand, the percentage of industry employment in jobs that involve high interaction with the public has a negative effect on year-over-year employment change in April and May, but not in the months of June to September. These different results related to physical proximity and interaction with the public are driven, in part, by the uneven impacts of COVID-19 on hospitality and retail businesses.
Rate of sepsis hospitalizations after misdiagnosis in adult emergency department patients: a look-forward analysis with administrative claims data using Symptom-Disease Pair Analysis of Diagnostic Error (SPADE) methodology in an integrated health system
Authors: Horberg Michael A. , Nassery Najlla , Rubenstein Kevin B. , Certa Julia M. , Shamim Ejaz A. , Rothman Richard , Wang Zheyu , Hassoon Ahmed , Townsend Jennifer L. , Galiatsatos Panagis , Pitts Samantha I. , Newman-Toker David E. 
Published: April 2021

Abstract

Objectives
Delays in sepsis diagnosis can increase morbidity and mortality. Previously, we performed a Symptom-Disease Pair Analysis of Diagnostic Error (SPADE) “look-back” analysis to identify symptoms at risk for delayed sepsis diagnosis. We found treat-and-release emergency department (ED) encounters for fluid and electrolyte disorders (FED) and altered mental status (AMS) were associated with downstream sepsis hospitalizations. In this “look-forward” analysis, we measure the potential misdiagnosis-related harm rate for sepsis among patients with these symptoms.

Methods
Retrospective cohort study using electronic health record and claims data from Kaiser Permanente Mid-Atlantic States (2013–2018). Patients ≥18 years with ≥1 treat-and-release ED encounter for FED or AMS were included. Observed greater than expected sepsis hospitalizations within 30 days of ED treat-and-release encounters were considered potential misdiagnosis-related harms. Temporal analyses were employed to differentiate case and comparison (superficial injury/contusion ED encounters) cohorts.

Results
There were 4,549 treat-and-release ED encounters for FED or AMS, 26 associated with a sepsis hospitalization in the next 30 days. The observed (0.57%) minus expected (0.13%) harm rate was 0.44% (absolute) and 4.5-fold increased over expected (relative). There was a spike in sepsis hospitalizations in the week following FED/AMS ED visits. There were fewer sepsis hospitalizations and no spike in admissions in the week following superficial injury/contusion ED visits. Potentially misdiagnosed patients were older and more medically complex.

Conclusions
Potential misdiagnosis-related harms from sepsis are infrequent but measurable using SPADE. This look-forward analysis validated our previous look-back study, demonstrating the SPADE approach can be used to study infectious disease syndromes.
Indoor storage time affects the quality and quantity of volatile monoterpenes emitted from softwood timber
Authors: Muilu-Mäkelä Riina , Kilpeläinen Petri , Kitunen Veikko , Harju Anni , Venäläinen Martti , Sarjala Tytti 
Published: April 2021

Abstract
Wood as a construction material affects indoor environmental quality by moisture buffering, good acoustic properties and by the wood specific volatile organic compounds (VOC). The most abundant VOCs of soft wood are volatile monoterpenes (VM) giving the typical odor of wood. In the present study, long-term VM emissions of wood of two northern coniferous tree species, Scots pine and Norway spruce were observed regularly during one year in storage. Fresh and dried 20 cm long wood blocks were placed in a test chamber; VMs were collected with the solid phase micro extraction fiber and analyzed by gas chromatography-mass spectrometer. Average emission of nine different VMs, α- and β-pinene, 3-carene, limonene, terpinolene, myrcene, camphene, ortho-cymene and ƴ-terpinene, decreased 68–87% during one-year long storage. Moisture content (MC), knots, tree species and tree individual affected the VM emissions from wood. When a certain level of MC (12%) was reached, the VM levels decreased, but the method of drying (industrial or dried in storage) did not affect the amount of released VMs. Rehydration and dehydration increased and decreased VM emissions, respectively. Moreover, two of the eight Scots pine heartwood planks contained almost no 3-carene while being the most abundant monoterpene in the others.
IL-24 inhibits the malignancy of human glioblastoma cells via destabilization of Zeb1
Authors: Lin Tie , Wang Dongpeng , Chen Jun , Zhang Zhan , Zhao Yuming , Wu Zhong , Wang Yuehua 
Published: April 2021

Abstract
Glioblastoma (GBM) is the most common and fatal type of primary malignant tumours in the central nervous system. Cytokines such as interleukins (ILs) play an important role in GBM progression. Our present study found that IL-24 is down-regulated in GBM cells. Recombinant IL-24 (rIL-24) can suppress the in vitro migration and invasion of GBM cells while increase its chemo-sensitivity to temozolomide (TMZ) treatment. rIL-24 negatively regulates the expression of Zeb1, one well known transcription factors of epithelial to mesenchymal transition (EMT) of cancer cells. Over expression of Zeb1 can attenuate IL-24-suppressed malignancy of GBM cells. Mechanistically, IL-24 decreases the protein stability of Zeb1 while has no effect on its mRNA stability. It is due to that IL-24 can increase the expression of FBXO45, which can destabilize Zeb1 in cancer cells. Collectively, we reveal that IL-24 can suppress the malignancy of GBM cells via decreasing the expression of Zeb1. It suggests that targeted activation of IL-24 signals might be a potential therapy approach for GBM treatment.
Optimal placement of distributed generation based on DISCO’s additional benefit using self adaptive levy flight based black widow optimization
Authors: Gubbala Venkata Naga Lakshmi , Askani Jaya Laxmi , Veeramsetty Venkataramana 
Published: April 2021

Abstract
Optimal placement of Distributed Generation (DG) is a crucial challenge for Distribution Companies (DISCO’s) to run the distribution network in good operating conditions. Optimal positioning of DG units is an optimization issue where maximization of DISCO’s additional benefit due to the installation of DG units in the network is considered to be an objective function. In this article, the self adaptive levy flight based black widow optimization algorithm is used as an optimization strategy to find the optimum position and size of the DG units. The proposed algorithm is implemented in the IEEE 15 and PG & E 69 bus management systems in the MATLAB environment. Based on the simulation performance, it has been found that with the correct location and size of the DG modules, the distribution network can be run with maximum DISCO’s additional benefit.
An efficient class of fourth-order derivative-free method for multiple-roots
Authors: Kumar Sunil , Kumar Deepak , Sharma Janak Raj , Argyros Ioannis K. 
Published: April 2021

Abstract
Many optimal order multiple root techniques, which use derivatives in the algorithm, have been proposed in literature. Many researchers tried to construct an optimal family of derivative-free methods for multiple roots, but they did not get success in this direction. With this as a motivation factor, here, we present a new optimal class of derivative-free methods for obtaining multiple roots of nonlinear functions. This procedure involves Traub–Steffensen iteration in the first step and Traub–Steffensen-like iteration in the second step. Efficacy is checked on a good number of relevant numerical problems that verifies the efficient convergent nature of the new methods. Moreover, we find that the new derivative-free methods are just as competent as the other existing robust methods that use derivatives.
Scholars, Priests, and Temples: Babylonian and Egyptian Science in Context. Introduction
Authors: Ossendrijver Mathieu 
Published: April 2021

AbstractThis article introduces a double issue comprising 11 papers about Babylonian and Egyptian priests and scholarship between ca. 600bceand 200ce. They constitute the proceedings of the workshop “Scholars, Priests, and Temples: Babylonian and Egyptian Science in Context”, which was held at the Humboldt University Berlin, 12–14 May 2016, with support of the Excellence Cluster TOPOI. The workshop brought together Assyriologists and Egyptologists with expertise in Babylonian and Egyptian scholarship, priesthoods and temple institutions. All contributions have been revised and updated since then. The present contribution offers a brief introduction on previous research, cross-cultural interactions, economic aspects, royal patronage, and internal developments of Babylonian and Egyptian temple scholarship, followed by short summaries of the papers.
Edgar Wind on Experiment and Metaphysics
Authors: Falkenburg Brigitte 
Published: April 2021

AbstractThe paper presents a detailed interpretation of Edgar Wind’sExperiment and Metaphysics(1934), a unique work on the philosophy of physics which broke with the Neo-Kantian tradition under the influence of American pragmatism. Taking up Cassirer’s interpretation of physics, Wind develops a holistic theory of the experiment and a constructivist account of empirical facts. Based on the concept of embodiment which plays a key role in Wind’s later writings on art history, he argues, however, that the outcomes of measurements are contingent. He then proposes an anti-Kantian conception of a metaphysics of nature. For him, nature is an unknown totality which manifests itself in discrepancies between theories and experiment, and hence the theory formation of physics can increasingly approximate the structure of nature. It is shown that this view is ambiguous between a transcendental, metaphysical realism in Kant’s sense and an internal realism in Putnam’s sense. Wind’s central claim is that twentieth century physics offers new options for resolving Kant’s cosmological antinomies. In particular, he connected quantum indeterminism with the possibility of human freedom, a connection that Cassirer sharply opposed.