bluuebunny/crossref_metadata_2025_split huggingface dataset:
Time Dilation and Length Contraction
Authors: Wittman David M. 
Published: August 2018

Abstract
In Chapter 6, we discovered that different frames mix time and space differently; in this chapter, we will discover that speed causes time to run slowly and space to contract. Of course, the truth is a bit subtler than that, because when two frames are in relative motion each frame measures the other as the high‐speed frame where time runs slowly and space contracts.We deduce time dilation and length contraction in multiple ways: first with a light clock as a thinking tool, and then with spacetime diagrams and a new thinking tool called the symmetric frame. We also examine the experimental proof of these effects. By the end of this chapter, you will understand how time dilation and length contraction fit together with time skew in a fully consistent model that beautifully fits a wide range of evidence.
Doppler Effect and Velocity Addition Law
Authors: Wittman David M. 
Published: August 2018

Abstract
We now pivot from relationships between frames to look at the effect of motion on communications between specific observers.This will help us look at the twin paradox in the next chapter, and will prove crucial to understanding the effects of gravity on time. Along the way, we develop an understanding of the Doppler effect; a key tool in many areas of modern science. We find that Doppler effects are reciprocal (Alice observes the same effect on Bob’s signals as Bob observes on Alice’s signals) and that Doppler effects compound over multiple frame changes. We then use the compounding of Doppler effects to deduce the algebraic formof the velocity addition law. We show that this Einstein velocity addition law reduces to the Galilean law at low speeds.
Energy and Momentum
Authors: Wittman David M. 
Published: August 2018

Abstract
Tis chapter explains the famous equation E = mc2 as part of a wider relationship between energy, mass, and momentum. We start by defning energy and momentum in the everyday sense. We then build on the stretching‐triangle picture of spacetime vectors developed in Chapter 11 to see how energy, mass, and momentum have a deep relationship that is not obvious at everyday low speeds. When momentum is zero (a mass is at rest) this energy‐momentum relation simplifes to E = mc2, which implies that mass at rest quietly stores tremendous amounts of energy. Te energymomentum relation also implies that traveling near the speed of light (e.g., to take advantage of time dilation for interstellar journeys) will require tremendous amounts of energy. Finally, we look at the simplifed form of the energy‐momentum relation when the mass is zero. Tis gives us insight into the behavior of massless particles such as the photon.
Orbits
Authors: Wittman David M. 
Published: August 2018

Abstract
Orbits are ubiquitous in the universe: moons orbit planets, planets orbit stars, stars orbit around the center of the Milky Way galaxy, and so on. Any theory of gravity will have to explain the properties of all these orbits. To pave the way for developing the metric theory of gravity (general relativity) this chapter examines the basics of orbits as observed and as explained by the Newtonian model of gravity. We can use our understanding of gravity to infer the masses and other properties of these cosmic systems. Te chapter concludes with four optional sections in this spirit, covering the slingshot maneuver; dark matter; binary star orbits and how they reveal the masses of stars; and extrasolar planets.
In the Path of the Storm: Does Distress Risk Cause Industrial Firms to Risk-Shift?*
Authors: Aretz Kevin , Banerjee Shantanu , Pryshchepa Oksana 
Published: August 2018

Abstract
We study whether industrial firms risk-shift in response to distress risk increases induced through hurricane strikes. Using new proxies capturing deliberate managerial decisions about the risk of a firm’s operating segment portfolio, differences tests suggest that hurricane strikes prompt moderately, but not highly, distressed firms to skew their asset mixes toward riskier segments by shutting down low-risk, high-average-Q segments. In turn, the moderately distressed firms observe abnormally high failure rates after a hurricane strike. Employing covenant violation data, we offer further evidence that creditor control prevents highly distressed firms from raising their risk. Our conclusions extend those of other studies by suggesting that moderate distress risk levels can lead the managers of industrial firms to not only engage in risk-taking, but, in fact, in risk-shifting.
Is Social Work Still Racist? A Content Analysis of Recent Literature
Authors: Corley Nicole A , Young Stephen M 
Published: August 2018

Abstract
Addressing systems of oppression that disproportionately affect racial and ethnic minoritized groups appears to be of marginal interest in social work’s professional literature. This article describes the content analysis of articles on Asian Pacific Islander (API) Americans, African Americans, Latinx or Hispanic Americans, and Native or Indigenous Americans in four major social work journals published between 2005 and 2015. (The analysis serves to update a 1992 article by Anthony McMahon and Paula Allen-Meares that examined literature between 1980 and 1989.) Of the 1,690 articles published in Child Welfare, Research on Social Work Practice, Social Service Review, and Social Work over an 11-year period, only 123 met the criteria for inclusion. Findings suggest that social work researchers are still failing to address institutional racism and are relying heavily on micro-level interventions when working with minoritized groups. Social workers need to increase efforts to dismantle institutional racism.
Plasma membrane cholesterol trafficking in steroidogenesis
Authors: Deng Bing , Shen Wen-Jun , Dong Dachuan , Azhar Salman , Kraemer Fredric B. 
Published: August 2018

ABSTRACTCholesterol is an important component of plasma membranes (PMs) and the precursor of all steroid hormones. In steroidogenic tissues, upon hormone stimulation, there is a rapid transfer of cholesterol to the mitochondria, which is the site of the initial step in steroidogenesis. In the current study, we examined PM cholesterol trafficking for steroidogenesis. In a mitochondrial reconstitution assay, adrenal PMs supported steroidogenesis in the absence of additional transport proteins. Depletion of cholesterol in PMs by 50% eliminated the membranes' ability to support steroidogenesis in vitro and reduced steroid production in intact Y1 adrenocortical cells. Syntaxin (STX)‐5 and α‐soluble N‐emylmaleimide‐sensitive factor attachment protein (α‐SNAP) are enriched in adrenal PMs, and adrenocorticotropic hormone treatment of rats recruited STX5 and α‐SNAP to adrenal PMs and mitochondria. Immunodepletion of STX5 and α‐SNAP from PMs decreased steroidogenesis supported by PMs in vitro. Protease digestion of PMs decreased, whereas recombinant STX5 or α‐SNAP restored, the PMs' ability to support steroidogenesis. Knockdown of either STX5 or α‐SNAP in Y1 cells decreased stimulated steroidogenesis. These results indicate that STX5 and α‐SNAP facilitate cholesterol trafficking from PMs to mitochondria for adrenal steroid synthesis and underscore the importance of vesicular trafficking of PM cholesterol for steroidogenesis.—Deng, B., Shen, W.‐J., Dong, D., Azhar, S., Kraemer, F. B. Plasma membrane cholesterol trafficking in steroidogenesis. FASEB J. 33, 389–1400 (2019). www.fasebj.org
Chronic psychosocial defeat differently affects lipid metabolism in liver and white adipose tissue and induces hepatic oxidative stress in mice fed a high‐fat diet
Authors: Giudetti Anna M. , Testini Mariangela , Vergara Daniele , Priore Paola , Damiano Fabrizio , Gallelli Cristina Anna , Romano Adele , Villani Rosanna , Cassano Tommaso , Siculella Luisa , Gnoni Gabriele V. , Moles Anna , Coccurello Roberto , Gaetani Silvana 
Published: August 2018

ABSTRACTIt is widely accepted that chronic stress may alter the homeostatic mechanisms of body weight control. In this study, we followed the metabolic changes occurring in mice when chronic stress caused by psychosocial defeat (CPD) is associated with ad libitum exposure to a palatable high‐fat diet (HFD). In this model, CPD mice consumed more HFD than unstressed (Un) mice without gaining body weight. We focused on metabolic processes involved in weight control, such as de novo lipogenesis (DNL), fatty acid β‐oxidation (FAO), and thermogenesis. The activity and expression of DNL enzymes were reduced in the liver and white adipose tissue of mice consuming the HFD. Such effects were particularly evident in stressed mice. In both CPD and Un mice, HFD consumption increased the hepatic expression of the mitochondrial FAO enzyme carnitine palmitoyltransferase‐1. In the liver of mice consuming the HFD, stress exposure prevented accumulation of triacylglycerols; however, accumulation of triacylglycerols was observed in Un mice under the same dietary regimen. In brown adipose tissue, stress increased the expression of uncoupling protein‐1, which is involved in energy dissipation, both in HFD and control diet‐fed mice. We consider increased FAO and energy dissipation responsible for the antiobesity effect seen in CPD/HFD mice. However, CPD associated with HFD induced hepatic oxidative stress.—Giudetti, A. M., Testini, M., Vergara, D., Priore, P., Damiano, F., Gallelli, C. A., Romano, A., Villani, R., Cassano, T., Siculella, L., Gnoni, G. V., Moles, A., Coccurello, R., Gaetani, S. Chronic psychosocial defeat differently affects lipid metabolism in liver and white adipose tissue and induces hepatic oxidative stress in mice fed a high‐fat diet. FASEB J. 33, 1428–1439 (2019). www.fasebj.org
Defining Empathy to Better Teach, Measure, and Understand Its Impact
Authors: Dohrenwend Anne M. 
Published: August 2018

No consensus on the definition of empathy exists. Empathy has been described as emotional and spontaneous, cognitive and deliberate, or some combination of the two. Attentive nonverbal reactions, feeling reflections, reassurance, sympathy, and compassion all have been conflated with empathy, making it impossible to differentiate empathy from other communication skills. This confusion over the definition of empathy has affected its measurement. For example, the authors of the Interpersonal Reactivity Index see empathy as multidimensional, involving both emotional and cognitive aspects, while the authors of the Jefferson Scale of Physician Empathy see empathy as a predominately cognitive process. Researchers, such as Yamada and colleagues in their study in this issue, then must straddle these conceptualizations, which is a limitation to their work.
To address this problem, the author of this Invited Commentary proposes adopting the cognitive definition of empathy, noting that it allows physicians to distinguish between empathy and other communication skills and is the most consistent with counseling psychology descriptions. The author defines cognitive empathy as a conscious, strenuous, mental effort to clarify a patient’s muddy expression of her experience using a soft interpretation of her story. Accurate empathic responses are unadulterated by a physician’s reactions to a patient and the patient’s experience. The author describes four aspects of empathy that are rarely noted in the medical literature but that are fundamental to understanding its practice: the “as if” condition, the use of soft interpretation, the primacy of cognition, and the relevance of reflection.
Pilomatrixoma: A Comprehensive Review of the Literature
Authors: Jones Christopher D. , Ho Weiguang , Robertson Bernard F. , Gunn Eilidh , Morley Stephen 
Published: August 2018

Introduction:
Pilomatrixoma, also known as calcifying epithelioma of Malherbe, is a superficial benign skin tumor that arises from hair follicle matrix cells. Although pilomatrixomas are well-recognized lesions, clinically they are frequently misdiagnosed as other skin conditions. By reviewing all the literature over the past 10 years, the aims of this article are to analyze the cause, clinical presentation, management, and outcome of pilomatrixoma among children and adults to gain a more complete understanding of this lesion in today's clinical context.

Methods:
A MEDLINE and EMBASE search was conducted from January 2005 to February 2015 using a combination of the terms: “child,” “childhood,” “adult,” and keywords: “pilomatrixoma,” “pilomatricoma,” and “calcifying epithelioma of Malherbe.” A total of 150 articles were reviewed.

Results:
The lesions occurred most commonly in the first and second decades (mean age 16 years and 7 months). The commonest presentation was of an asymptomatic, firm, slowly growing, mobile nodule. Only 16% were accurately diagnosed on clinical examination. Imaging in the form of ultrasound, computed tomography, and magnetic resonance imaging has been reported. Pathological diagnosis was achieved through incision, punch, and shave biopsies. Pathological findings are discussed and summarized in this review.

Conclusion:
Pilomatrixomas are thought to arise from mutation in the Wnt pathway and has been linked to several genetic conditions. It is commonly misdiagnosed preoperatively; however, with better awareness of the lesion, it can be appropriately treated while avoiding unnecessary diagnostic tests. Complete surgical excision with clear margins is almost always curative.
Embryologic and Fetal Development of the Human Orbit
Authors: Tawfik Hatem A. , Dutton Jonathan J. 
Published: August 2018

Purpose:
To review the recent data about orbital development and sort out the controversies from the very early stages during embryonic life till final maturation of the orbit late in fetal life, and to appreciate the morphogenesis of all the definitive structures in the orbit in a methodical and timely fashion.

Methods:
The authors extensively review major studies detailing every aspect of human embryologic and fetal orbital morphogenesis including the development of extraocular muscles, orbital fat, vessels, nerves, and the supportive connective tissue framework as well as bone. These interdisciplinary studies span almost a century and a half, and include some significant controversial opposing points of view which the authors hopefully sort out. The authors also highlight a few of the most noteworthy molecular biologic studies regarding the multiple and interacting signaling pathways involved in regulating normal orbital morphogenesis.

Results:
Orbital morphogenesis involves a successive series of subtle yet tightly regulated morphogenetic events that could only be explained through the chronological narrative used by the authors. The processes that trigger and contribute to the formation of the orbits are complex and seem to be intricately regulated by multifaceted interactions and bidirectional cross-talk between a multitude of cellular building raw materials including the developing optic vesicles, neuroectoderm, cranial neural crest cells and mesoderm.

Conclusions:
Development of the orbit is a collective enterprise necessitating interactions between, as well as contributions from different cell populations both within and beyond the realm of the orbit. A basic understanding of the processes underlying orbital ontogenesis is a crucial first step toward establishing a genetic basis or an embryologic link with orbital disease.
Efficacy of Care for Blind Painful Eyes
Authors: Idowu Oluwatobi O. , Ashraf Davin C. , Kalin-Hajdu Evan , Ryan Michael C. , Kersten Robert C. , Vagefi M. Reza 
Published: August 2018

Purpose:
Pain relief for a blind painful eye often follows an escalating paradigm of interventions. This study compares the efficacy of common interventions.

Methods:
A retrospective chart review of blind painful eye cases was conducted at a single tertiary institution from April 2012 to December 2016. Demographics, etiology, treatment, and pain level were assessed.

Results:
Among 99 blind painful eyes, 96 eyes initially received medical therapy (topical steroids, cycloplegics, and/or hypotensives), with pain relief in 39% of eyes. Minimally invasive interventions (laser cyclophotocoagulation, retrobulbar injection, or corneal electrocautery) were performed 41 times in 36 eyes, 34 of which had failed medical therapy, and led to pain relief in 75% of eyes. Evisceration or enucleation was performed in 28 eyes, and long-term pain relief was achieved in 100% of eyes. Surgery allowed discontinuation of oral analgesics in 100% of cases versus 20% for minimally invasive therapy (p = 0.005) and 14% for medical therapy (p = 0.0001). Compared with medical therapy, minimally invasive therapy was 2.5 times more likely to achieve lasting pain relief (p = 0.003) and surgical therapy 35.6 times more likely to achieve lasting pain relief (p = 0.011). High initial pain score was associated with nonsurgical treatment failure.

Conclusions:
Medical therapy provides pain relief in a moderate number of patients with a blind painful eye. When medical therapy fails, minimally invasive therapy and surgical interventions are successively more effective in relieving ocular pain. High initial pain score is a risk factor for nonsurgical therapy failure and may merit an earlier discussion of surgical intervention.
Entrainment and maintenance of an internal metronome in premotor cortex
Authors: Cadena-Valencia J , García-Garibay O , Merchant H , Jazayeri M , de Lafuente V 
Published: August 2018

AbstractTo prepare timely motor actions we constantly predict future events. Regularly repeating events are often perceived as a rhythm to which we can readily synchronize our movements, just as in dancing to music. However, the neuronal mechanisms underlying the capacity to encode and maintain rhythms are not understood. We trained nonhuman primates to maintain the rhythm of a visual metronome of different tempos and then we recorded neural activity in the supplementary motor area (SMA). SMA exhibited rhythmic bursts of gamma band (30-40 Hz) reflecting an internal tempo that matched the extinguished visual metronome. Moreover, gamma amplitude increased throughout the trial and provided an estimate of total elapsed time. Notably, the timing and amplitude of gamma bursts reflected systematic timing biases and errors in the behavioral responses. Our results indicate that premotor areas use dynamic motor plans to encode a metronome for rhythms and a stopwatch for total elapsed time.
Dynamic representations of faces in the human ventral visual stream link visual features to behaviour
Authors: Dima Diana C. , Singh Krish D. 
Published: August 2018

AbstractHumans can rapidly extract information from faces even in challenging viewing conditions, yet the neural representations supporting this ability are still not well understood. Here, we manipulated the presentation duration of backward-masked facial expressions and used magnetoencephalography (MEG) to investigate the computations underpinning rapid face processing. Multivariate analyses revealed two stages in face perception, with the ventral visual stream encoding facial features prior to facial configuration. When presentation time was reduced, the emergence of sustained featural and configural representations was delayed. Importantly, these representations explained behaviour during an expression recognition task. Together, these results describe the adaptable system linking visual features, brain and behaviour during face perception.
Novel cholera toxin variant and ToxT regulon in environmentalVibrio mimicusstrains: potential resources for the evolution ofVibrio choleraehybrid strains
Authors: Neogi Sucharit Basu , Chowdhury Nityananda , Awasthi Sharda Prasad , Asakura Masahiro , Mahmud Zahid Hayat , Islam Mohammad Sirajul , Hinenoya Atsushi , Nair Gopinath Balakrish , Yamasaki Shinji 
Published: August 2018

ABSTRACTAtypical El Tor strains ofVibrio choleraeO1 harboring variantctxBgenes of cholera toxin (CT) are gradually becoming a major cause of recent cholera epidemics.Vibrio mimicusoccasionally contains virulence factors associated with cholera, e.g., CT, encoded byctxABon CTXФ genome; and TCP, the CTXФ-specific receptor. This study carried out extensive molecular characterization of CTXФ and ToxT regulon inctx+vestrains ofV. mimicusisolated from the Bengal coast. Southern hybridization, PCR, and DNA sequencing of virulence related-genes revealed the presence of an El Tor type CTX prophage (CTXET) carrying a novelctxAB, tandem copies of environmental type pre-CTX prophage (pre-CTXEnv), and RS1 elements, which were organized in an array of RS1-CTXET-RS1-pre-CTXEnv-pre-CTXEnv. Additionally, a novel variant oftcpAandtoxTrespectively, showing clonal lineage to a phylogenetic clade ofV. choleraenon-O1/O139, was identified. TheV. mimicusstrains lacked the RTX and TLC elements, andVibrioseventh pandemic islands of the El Tor strains, but contained five heptamer (TTTTGAT) repeats inctxABpromoter region like some classical strains ofV. choleraeO1. PFGE analysis showed all thectx+veV. mimicusstrains were clonally related. However, theirin vitroCT production andin vivotoxigenecity were variable, which could be explained by differential transcription of virulence genes along with ToxR regulon. Taken together, our findings strongly suggest that environmentalV. mimicusstrains act as potential reservoir of atypical virulence factors, including variant CT and ToxT regulon, and may contribute to the evolution ofV. choleraehybrid strains.IMPORTANCENatural diversification of CTXФ andctxABgenes certainly influences disease severity and shifting patterns in major etiological agents of cholera, e.g., the overwhelming emergence of hybrid El Tor variants, replacing the prototype El Tor strains ofV. cholerae. This study showing the occurrence of CTXETcomprising a novel variant ofctxABinV. mimicuspoints out a previously unnoticed evolutionary event, independent to that of the El Tor strains ofV. cholerae. Identification and cluster analysis of the newly-discovered alleles oftcpAandtoxTindicates their horizontal transfer from an uncommon clone ofV. cholerae. The genomic content of ToxT regulon, and tandemly arranged multiple pre-CTXФEnvand a CTXФETinV. mimicusprobably act as salient raw materials inducing natural recombination among the hallmark virulence genes of hybridV. choleraestrains. This study will facilitate deeper understanding of the evolution of new variant CT and ToxT regulon, influencing cholera epidemiology.