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2021 ◽  
pp. 147612702110679
Author(s):  
Owen Nelson Parker ◽  
Ke Gong ◽  
Rachel Mui

Organizational reputation is compelling to layman audiences, it is critical for firm performance and myriad organizational phenomena, and recent theory articulates how it shapes the very managerial discretion underpinning strategic decisions. Yet, reputation is still excluded from much of mainstream strategic organization research. We make the case for reputation’s wider inclusion in studies of managerial discretion or strategic decision-making. We first demonstrate reputation’s potential theoretical importance in explaining nuances or non-findings in such studies, detail ways to measure reputation accurately, provide five sources of data for readers to facilitate the inclusion of reputation in their studies, and illustrate how scholars can use freelancers to collect their own archival data for their own, context-specific purposes. By shedding light on reputation’s unique role in shaping managerial discretion and, thereby, strategic decisions, we hope this essay helps scholars better account for decision-making patterns that might otherwise defy the predictions of other organizational theories.


2021 ◽  
Vol 288 (1964) ◽  
Author(s):  
Tom M. Allison ◽  
Arunas L. Radzvilavicius ◽  
Damian K. Dowling

Uniparental inheritance (UPI) of mitochondria predominates over biparental inheritance (BPI) in most eukaryotes. However, examples of BPI of mitochondria, or paternal leakage, are becoming increasingly prevalent. Most reported cases of BPI occur in hybrids of distantly related sub-populations. It is thought that BPI in these cases is maladaptive; caused by a failure of female or zygotic autophagy machinery to recognize divergent male-mitochondrial DNA ‘tags’. Yet recent theory has put forward examples in which BPI can evolve under adaptive selection, and empirical studies across numerous metazoan taxa have demonstrated outbreeding depression in hybrids attributable to disruption of population-specific mitochondrial and nuclear genotypes (mitonuclear mismatch). Based on these developments, we hypothesize that BPI may be favoured by selection in hybridizing populations when fitness is shaped by mitonuclear interactions. We test this idea using a deterministic, simulation-based population genetic model and demonstrate that BPI is favoured over strict UPI under moderate levels of gene flow typical of hybridizing populations. Our model suggests that BPI may be stable, rather than a transient phenomenon, in hybridizing populations.


Author(s):  
Taru Gupta ◽  
Divya Baruhee ◽  
Sunaina Agarwal

Background: Recent theory on ovarian malignancy suggests its origin from primary foci in fallopian tubes. Prophylactic salpingectomy may benefit in risk reduction of ovarian cancer. The aim of the study was to compare the feasibility of complete salpingectomy with bilateral tubal ligation was made during caesarean delivery in women desirous of permanent sterilisation.Methods: We conducted a prospective interventional randomized control study in department of obstetrics and gynaecology, ESI-PGIMSR Basaidarapur, New Delhi from October 2018 to February 2021. 70 women participated in this study desiring permanent sterilisation during caesarean delivery. Patients were randomized into two groups who either underwent bilateral tubal ligation [group A (N=35)] or complete bilateral salpingectomy [group B (N=35)].Results: Procedure was completed in 91% patients in group A and 77% in group B (p >0.05) making both the procedures feasible.  Total operative time (min) in group A and B were 47 and 55 respectively (p<0.01). Mean sterilisation procedure time (min) in group A was 5 and group B was 6 (p=0.13). No significant difference was seen in intra-operative blood loss (400 ml in group A vs 300 ml in group B), percentage decrease in post-op haemoglobin (g/dl) (4.56±2.96 in group A vs 3.91±2.7 in group B), post-operative serum Anti-mullerian hormone (AMH) levels (ng/ml) (group A-0.965±0.12 vs 0.7±0.09 in group B) in the two groups.Conclusions: Salpingectomy as an alternative to tubal ligation should be discussed with suitable patients desirous of permanent sterilisation during caesarean delivery. 


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Soogil Lee ◽  
Min-Gu Kang ◽  
Dongwook Go ◽  
Dohyoung Kim ◽  
Jun-Ho Kang ◽  
...  

AbstractSpin Hall effect, an electric generation of spin current, allows for efficient control of magnetization. Recent theory revealed that orbital Hall effect creates orbital current, which can be much larger than spin-Hall-induced spin current. However, orbital current cannot directly exert a torque on a ferromagnet, requiring a conversion process from orbital current to spin current. Here, we report two effective methods of the conversion through spin-orbit coupling engineering, which allows us to unambiguously demonstrate orbital-current-induced spin torque, or orbital Hall torque. We find that orbital Hall torque is greatly enhanced by introducing either a rare-earth ferromagnet Gd or a Pt interfacial layer with strong spin-orbit coupling in Cr/ferromagnet structures, indicating that the orbital current generated in Cr is efficiently converted into spin current in the Gd or Pt layer. Our results offer a pathway to utilize the orbital current to further enhance the magnetization switching efficiency in spin-orbit-torque-based spintronic devices.


2021 ◽  
Vol 81 (11) ◽  
Author(s):  
Ayan Banerjee ◽  
Anirudh Pradhan ◽  
Takol Tangphati ◽  
Farook Rahaman

AbstractFollowing the recent theory of f(Q) gravity, we continue to investigate the possible existence of wormhole geometries, where Q is the non-metricity scalar. Recently, the non-metricity scalar and the corresponding field equations have been studied for some spherically symmetric configurations in Mustafa (Phys Lett B 821:136612, 2021) and Lin and Zhai (Phys Rev D 103:124001, 2021). One can note that field equations are different in these two studies. Following Lin and Zhai (2021), we systematically study the field equations for wormhole solutions and found the violation of null energy conditions in the throat neighborhood. More specifically, considering specific choices for the f(Q) form and for constant redshift with different shape functions, we present a class of solutions for static and spherically symmetric wormholes. Our survey indicates that wormhole solutions could not exist for specific form function $$f(Q)= Q+ \alpha Q^2$$ f ( Q ) = Q + α Q 2 . To summarize, exact wormhole models can be constructed with violation of the null energy condition throughout the spacetime while being $$\rho \ge 0$$ ρ ≥ 0 and vice versa.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Hongsheng Fang ◽  
Yunlan Du ◽  
Shuting Pan ◽  
Ming Zhong ◽  
Jiayin Tang

Abstract Background Recent theory on the “gut-brain axis” suggests a close relationship between the dysfunction of the gut and the disorders of the brain. Methods We performed a systemic literature search followed by a multi-step inclusion selection for all studies on the risk of Colorectal cancer (CRC) in Parkinson’s disease (PD) patients using the following databases: PubMed, EMBASE and WOS. Relative risk (RR) and the 95% confidence intervals (CI) were calculated using either the random-effects model or the fixed-effects meta-analysis model, based on the assessment of heterogeneity. Results Seventeen studies involving a total of 375,964 PD patients and 879,307 cancer patients were included. Independent meta-analyses for cohort studies and case-control studies showed that the overall pooled RR of the cohort studies was 0.78 (0.66–0.91), and that of the case-control studies was 0.78 (0.65–0.94), indicating that patients with PD have a significantly decreased risk for CRC. The significant lower risk is present in both the colon and the rectum subgroups classified by tumor location. Moreover, the risk for CRC is significantly lower in America (RR = 0.58), Europe (RR = 0.82) and Asia (RR = 0.83) compared to the control population. Conclusion The occurrence of CRC was significantly lower in patients with diagnosis of PD.


2021 ◽  
Author(s):  
Keno Riechers ◽  
Takahito Mitsui ◽  
Niklas Boers ◽  
Michael Ghil

Abstract. The relative role of external forcing and of intrinsic variability is a key question of climate variability in general and of our planet’s paleoclimatic past in particular. Over the last 100 years since Milankovitch’s contributions, the role of orbital forcing has been well established for the last 2.6 Myr and their Quaternary glaciation cycles. A convincing case has also been made for the role of several internal mechanisms that are active on time scales both shorter and longer than the orbital ones. Such mechanisms clearly have a causal role in Dansgaard-Oeschger and Heinrich events, as well as in the mid-Pleistocene transition. We introduce herein a unified framework for the understanding of the interplay between internal mechanisms and orbital forcing on time scales from thousands to millions of years. This framework relies on the fairly recent theory of nonautonomous and random dynamical systems and it has been successfully applied so far in the climate sciences for problems like the El Niño-Southern Oscillation, the oceans’ wind-driven circulation, and other problems on interannual to interdecadal time scales. Finally, we provide further examples of climate applications and present preliminary results of interest for the Quaternary glaciation cycles in general and the mid-Pleistocene transition in particular.


Sci ◽  
2021 ◽  
Vol 3 (4) ◽  
pp. 35
Author(s):  
Peter Verheyen

How does the world around us work and what is real? This question has preoccupied humanity since its beginnings. From the 16th century onwards, it has periodically been necessary to revise the prevailing worldview—but things became very strange at the beginning of the 20th century with the advent of relativity theory and quantum physics. The current focus is on the role of information, there being a debate about whether this is ontological or epistemological. A theory has recently been formulated in which spacetime and gravity emerges from microscopic quantum information—more specifically from quantum entanglement via entanglement entropy. A recent theory describes the emergence of reality itself through first-person perspective experiences and algorithmic information theory. In quantum physics, perception and observation play a central role. Perception of and interaction with the environment require an exchange of information. Via biochemical projection, information is given an interpretation that is necessary to make life and consciousness possible. The world around us is not at all what it seems.


Author(s):  
Daniel Cardoso

An analysis of the consistency of the Abraham and Minkowski momenta in the determination of the photon trajectory was carried out considering a new principle of conservation of the photon's mechanical energy, in which the photon conserves translational energy in orbital angular momentum when transiting between two media, introducing the relativistic energy wave (REW). The confrontation between REW and the recent theory of space-time waves (ST) was considered, pondering your differences. Throughout this study it was possible to verify that the Abraham momentum appears a relativistic photon ignition device in the transition between two media, acting as the hidden momentum of the Minkowski&rsquo;s relativistic momentum. The wavy behavior in the matter is relativistic, and the relativistic trajectory appears with delays and advances, with points of synchronization between source-observer. The classical or relativistic trajectories are determined as a function of the angle of incidence and the relative refractive index, by one of two distinct non-additive torques, the classic by Abraham or the relativistic by Minkowski. It was found that the same analysis conducted under the principle of conservation of the mechanical energy of the photon can be treated by an new Doppler, Relativistic Apparent, that can be confused with other Dopplers in the treatment of redshift from distant sources. It was found that the conservation of energy in Orbital Angular Momentum (OAM), in the interaction with matter, explains that the synchronization instants are found in the inversion of the OAM, where the advances and delays of REW occur under negligible variations of the OAM, however, opposites.


2021 ◽  
pp. 194855062110464
Author(s):  
Pelin Gul ◽  
Nils Keesmekers ◽  
Pinar Elmas ◽  
Fatma Ebru Köse ◽  
Tolga Koskun ◽  
...  

A range of studies have sought to understand why people’s compliance with social distancing varied during the COVID-19 pandemic. Recent theory suggests that pathogen avoidance behavior is based not only on perceived risk but on a trade-off between the perceived costs of pathogen exposure and the perceived benefits of social contact. We hypothesized that compliance with social distancing may therefore be explained by a trade-off between pathogen avoidance and various social motives such as mate-seeking. Two studies conducted during the COVID-19 pandemic showed that social distancing was positively associated with disease avoidance motives but negatively associated with social motives, especially mating motives. These associations remained after controlling for predictors identified by previous research, including risk perception and personality. Findings indicate that people who are more interested in seeking new romantic partners (e.g., young men) may be less inclined to socially distance and be more at risk of pathogen transmission.


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